Commit | Line | Data |
---|---|---|
bcea3f96 | 1 | // SPDX-License-Identifier: GPL-2.0 |
bc0c38d1 SR |
2 | /* |
3 | * ring buffer based function tracer | |
4 | * | |
2b6080f2 | 5 | * Copyright (C) 2007-2012 Steven Rostedt <srostedt@redhat.com> |
bc0c38d1 SR |
6 | * Copyright (C) 2008 Ingo Molnar <mingo@redhat.com> |
7 | * | |
8 | * Originally taken from the RT patch by: | |
9 | * Arnaldo Carvalho de Melo <acme@redhat.com> | |
10 | * | |
11 | * Based on code from the latency_tracer, that is: | |
12 | * Copyright (C) 2004-2006 Ingo Molnar | |
6d49e352 | 13 | * Copyright (C) 2004 Nadia Yvette Chambers |
bc0c38d1 | 14 | */ |
2cadf913 | 15 | #include <linux/ring_buffer.h> |
273b281f | 16 | #include <generated/utsrelease.h> |
2cadf913 SR |
17 | #include <linux/stacktrace.h> |
18 | #include <linux/writeback.h> | |
bc0c38d1 | 19 | #include <linux/kallsyms.h> |
17911ff3 | 20 | #include <linux/security.h> |
bc0c38d1 | 21 | #include <linux/seq_file.h> |
2cadf913 | 22 | #include <linux/irqflags.h> |
bc0c38d1 | 23 | #include <linux/debugfs.h> |
8434dc93 | 24 | #include <linux/tracefs.h> |
4c11d7ae | 25 | #include <linux/pagemap.h> |
bc0c38d1 SR |
26 | #include <linux/hardirq.h> |
27 | #include <linux/linkage.h> | |
28 | #include <linux/uaccess.h> | |
76c813e2 | 29 | #include <linux/vmalloc.h> |
bc0c38d1 SR |
30 | #include <linux/ftrace.h> |
31 | #include <linux/module.h> | |
32 | #include <linux/percpu.h> | |
2cadf913 | 33 | #include <linux/splice.h> |
3f5a54e3 | 34 | #include <linux/kdebug.h> |
5f0c6c03 | 35 | #include <linux/string.h> |
f76180bc | 36 | #include <linux/mount.h> |
7e53bd42 | 37 | #include <linux/rwsem.h> |
5a0e3ad6 | 38 | #include <linux/slab.h> |
bc0c38d1 SR |
39 | #include <linux/ctype.h> |
40 | #include <linux/init.h> | |
f39650de | 41 | #include <linux/panic_notifier.h> |
2a2cc8f7 | 42 | #include <linux/poll.h> |
b892e5c8 | 43 | #include <linux/nmi.h> |
bc0c38d1 | 44 | #include <linux/fs.h> |
478409dd | 45 | #include <linux/trace.h> |
3fd49c9e | 46 | #include <linux/sched/clock.h> |
8bd75c77 | 47 | #include <linux/sched/rt.h> |
91edde2e VRB |
48 | #include <linux/fsnotify.h> |
49 | #include <linux/irq_work.h> | |
50 | #include <linux/workqueue.h> | |
86387f7e | 51 | |
cb1f98c5 SRG |
52 | #include <asm/setup.h> /* COMMAND_LINE_SIZE */ |
53 | ||
bc0c38d1 | 54 | #include "trace.h" |
f0868d1e | 55 | #include "trace_output.h" |
bc0c38d1 | 56 | |
73c5162a SR |
57 | /* |
58 | * On boot up, the ring buffer is set to the minimum size, so that | |
59 | * we do not waste memory on systems that are not using tracing. | |
60 | */ | |
55034cd6 | 61 | bool ring_buffer_expanded; |
73c5162a | 62 | |
a3ae76d7 | 63 | #ifdef CONFIG_FTRACE_STARTUP_TEST |
8e1b82e0 FW |
64 | /* |
65 | * We need to change this state when a selftest is running. | |
ff32504f FW |
66 | * A selftest will lurk into the ring-buffer to count the |
67 | * entries inserted during the selftest although some concurrent | |
5e1607a0 | 68 | * insertions into the ring-buffer such as trace_printk could occurred |
ff32504f FW |
69 | * at the same time, giving false positive or negative results. |
70 | */ | |
8e1b82e0 | 71 | static bool __read_mostly tracing_selftest_running; |
ff32504f | 72 | |
b2821ae6 | 73 | /* |
60efe21e MH |
74 | * If boot-time tracing including tracers/events via kernel cmdline |
75 | * is running, we do not want to run SELFTEST. | |
b2821ae6 | 76 | */ |
020e5f85 | 77 | bool __read_mostly tracing_selftest_disabled; |
b2821ae6 | 78 | |
60efe21e MH |
79 | void __init disable_tracing_selftest(const char *reason) |
80 | { | |
81 | if (!tracing_selftest_disabled) { | |
82 | tracing_selftest_disabled = true; | |
83 | pr_info("Ftrace startup test is disabled due to %s\n", reason); | |
84 | } | |
85 | } | |
a3ae76d7 SRG |
86 | #else |
87 | #define tracing_selftest_running 0 | |
88 | #define tracing_selftest_disabled 0 | |
60efe21e MH |
89 | #endif |
90 | ||
0daa2302 | 91 | /* Pipe tracepoints to printk */ |
a76d4648 | 92 | static struct trace_iterator *tracepoint_print_iter; |
0daa2302 | 93 | int tracepoint_printk; |
f3860136 | 94 | static bool tracepoint_printk_stop_on_boot __initdata; |
42391745 | 95 | static DEFINE_STATIC_KEY_FALSE(tracepoint_printk_key); |
0daa2302 | 96 | |
adf9f195 FW |
97 | /* For tracers that don't implement custom flags */ |
98 | static struct tracer_opt dummy_tracer_opt[] = { | |
99 | { } | |
100 | }; | |
101 | ||
8c1a49ae SRRH |
102 | static int |
103 | dummy_set_flag(struct trace_array *tr, u32 old_flags, u32 bit, int set) | |
adf9f195 FW |
104 | { |
105 | return 0; | |
106 | } | |
0f048701 | 107 | |
7ffbd48d SR |
108 | /* |
109 | * To prevent the comm cache from being overwritten when no | |
110 | * tracing is active, only save the comm when a trace event | |
111 | * occurred. | |
112 | */ | |
d914ba37 | 113 | static DEFINE_PER_CPU(bool, trace_taskinfo_save); |
7ffbd48d | 114 | |
0f048701 SR |
115 | /* |
116 | * Kill all tracing for good (never come back). | |
117 | * It is initialized to 1 but will turn to zero if the initialization | |
118 | * of the tracer is successful. But that is the only place that sets | |
119 | * this back to zero. | |
120 | */ | |
4fd27358 | 121 | static int tracing_disabled = 1; |
0f048701 | 122 | |
955b61e5 | 123 | cpumask_var_t __read_mostly tracing_buffer_mask; |
ab46428c | 124 | |
944ac425 SR |
125 | /* |
126 | * ftrace_dump_on_oops - variable to dump ftrace buffer on oops | |
127 | * | |
128 | * If there is an oops (or kernel panic) and the ftrace_dump_on_oops | |
129 | * is set, then ftrace_dump is called. This will output the contents | |
130 | * of the ftrace buffers to the console. This is very useful for | |
131 | * capturing traces that lead to crashes and outputing it to a | |
132 | * serial console. | |
133 | * | |
134 | * It is default off, but you can enable it with either specifying | |
135 | * "ftrace_dump_on_oops" in the kernel command line, or setting | |
cecbca96 FW |
136 | * /proc/sys/kernel/ftrace_dump_on_oops |
137 | * Set 1 if you want to dump buffers of all CPUs | |
138 | * Set 2 if you want to dump the buffer of the CPU that triggered oops | |
944ac425 | 139 | */ |
cecbca96 FW |
140 | |
141 | enum ftrace_dump_mode ftrace_dump_on_oops; | |
944ac425 | 142 | |
de7edd31 SRRH |
143 | /* When set, tracing will stop when a WARN*() is hit */ |
144 | int __disable_trace_on_warning; | |
145 | ||
681bec03 JL |
146 | #ifdef CONFIG_TRACE_EVAL_MAP_FILE |
147 | /* Map of enums to their values, for "eval_map" file */ | |
23bf8cb8 | 148 | struct trace_eval_map_head { |
9828413d SRRH |
149 | struct module *mod; |
150 | unsigned long length; | |
151 | }; | |
152 | ||
23bf8cb8 | 153 | union trace_eval_map_item; |
9828413d | 154 | |
23bf8cb8 | 155 | struct trace_eval_map_tail { |
9828413d SRRH |
156 | /* |
157 | * "end" is first and points to NULL as it must be different | |
00f4b652 | 158 | * than "mod" or "eval_string" |
9828413d | 159 | */ |
23bf8cb8 | 160 | union trace_eval_map_item *next; |
9828413d SRRH |
161 | const char *end; /* points to NULL */ |
162 | }; | |
163 | ||
1793ed93 | 164 | static DEFINE_MUTEX(trace_eval_mutex); |
9828413d SRRH |
165 | |
166 | /* | |
23bf8cb8 | 167 | * The trace_eval_maps are saved in an array with two extra elements, |
9828413d SRRH |
168 | * one at the beginning, and one at the end. The beginning item contains |
169 | * the count of the saved maps (head.length), and the module they | |
170 | * belong to if not built in (head.mod). The ending item contains a | |
681bec03 | 171 | * pointer to the next array of saved eval_map items. |
9828413d | 172 | */ |
23bf8cb8 | 173 | union trace_eval_map_item { |
00f4b652 | 174 | struct trace_eval_map map; |
23bf8cb8 JL |
175 | struct trace_eval_map_head head; |
176 | struct trace_eval_map_tail tail; | |
9828413d SRRH |
177 | }; |
178 | ||
23bf8cb8 | 179 | static union trace_eval_map_item *trace_eval_maps; |
681bec03 | 180 | #endif /* CONFIG_TRACE_EVAL_MAP_FILE */ |
9828413d | 181 | |
9c5b9d3d | 182 | int tracing_set_tracer(struct trace_array *tr, const char *buf); |
bcee5278 SRV |
183 | static void ftrace_trace_userstack(struct trace_array *tr, |
184 | struct trace_buffer *buffer, | |
36590c50 | 185 | unsigned int trace_ctx); |
b2821ae6 | 186 | |
ee6c2c1b LZ |
187 | #define MAX_TRACER_SIZE 100 |
188 | static char bootup_tracer_buf[MAX_TRACER_SIZE] __initdata; | |
b2821ae6 | 189 | static char *default_bootup_tracer; |
d9e54076 | 190 | |
55034cd6 | 191 | static bool allocate_snapshot; |
380af29b | 192 | static bool snapshot_at_boot; |
55034cd6 | 193 | |
cb1f98c5 SRG |
194 | static char boot_instance_info[COMMAND_LINE_SIZE] __initdata; |
195 | static int boot_instance_index; | |
196 | ||
9c1c251d SRG |
197 | static char boot_snapshot_info[COMMAND_LINE_SIZE] __initdata; |
198 | static int boot_snapshot_index; | |
199 | ||
1beee96b | 200 | static int __init set_cmdline_ftrace(char *str) |
d9e54076 | 201 | { |
c7dce4c5 | 202 | strscpy(bootup_tracer_buf, str, MAX_TRACER_SIZE); |
b2821ae6 | 203 | default_bootup_tracer = bootup_tracer_buf; |
73c5162a | 204 | /* We are using ftrace early, expand it */ |
55034cd6 | 205 | ring_buffer_expanded = true; |
d9e54076 PZ |
206 | return 1; |
207 | } | |
1beee96b | 208 | __setup("ftrace=", set_cmdline_ftrace); |
d9e54076 | 209 | |
944ac425 SR |
210 | static int __init set_ftrace_dump_on_oops(char *str) |
211 | { | |
2db7ab6b | 212 | if (*str++ != '=' || !*str || !strcmp("1", str)) { |
cecbca96 FW |
213 | ftrace_dump_on_oops = DUMP_ALL; |
214 | return 1; | |
215 | } | |
216 | ||
2db7ab6b | 217 | if (!strcmp("orig_cpu", str) || !strcmp("2", str)) { |
cecbca96 FW |
218 | ftrace_dump_on_oops = DUMP_ORIG; |
219 | return 1; | |
220 | } | |
221 | ||
222 | return 0; | |
944ac425 SR |
223 | } |
224 | __setup("ftrace_dump_on_oops", set_ftrace_dump_on_oops); | |
60a11774 | 225 | |
de7edd31 SRRH |
226 | static int __init stop_trace_on_warning(char *str) |
227 | { | |
933ff9f2 LCG |
228 | if ((strcmp(str, "=0") != 0 && strcmp(str, "=off") != 0)) |
229 | __disable_trace_on_warning = 1; | |
de7edd31 SRRH |
230 | return 1; |
231 | } | |
933ff9f2 | 232 | __setup("traceoff_on_warning", stop_trace_on_warning); |
de7edd31 | 233 | |
3209cff4 | 234 | static int __init boot_alloc_snapshot(char *str) |
55034cd6 | 235 | { |
9c1c251d SRG |
236 | char *slot = boot_snapshot_info + boot_snapshot_index; |
237 | int left = sizeof(boot_snapshot_info) - boot_snapshot_index; | |
238 | int ret; | |
239 | ||
240 | if (str[0] == '=') { | |
241 | str++; | |
242 | if (strlen(str) >= left) | |
243 | return -1; | |
244 | ||
245 | ret = snprintf(slot, left, "%s\t", str); | |
246 | boot_snapshot_index += ret; | |
247 | } else { | |
248 | allocate_snapshot = true; | |
249 | /* We also need the main ring buffer expanded */ | |
250 | ring_buffer_expanded = true; | |
251 | } | |
55034cd6 SRRH |
252 | return 1; |
253 | } | |
3209cff4 | 254 | __setup("alloc_snapshot", boot_alloc_snapshot); |
55034cd6 | 255 | |
7bcfaf54 | 256 | |
380af29b SRG |
257 | static int __init boot_snapshot(char *str) |
258 | { | |
259 | snapshot_at_boot = true; | |
260 | boot_alloc_snapshot(str); | |
261 | return 1; | |
262 | } | |
263 | __setup("ftrace_boot_snapshot", boot_snapshot); | |
264 | ||
265 | ||
cb1f98c5 SRG |
266 | static int __init boot_instance(char *str) |
267 | { | |
268 | char *slot = boot_instance_info + boot_instance_index; | |
269 | int left = sizeof(boot_instance_info) - boot_instance_index; | |
270 | int ret; | |
271 | ||
272 | if (strlen(str) >= left) | |
273 | return -1; | |
274 | ||
275 | ret = snprintf(slot, left, "%s\t", str); | |
276 | boot_instance_index += ret; | |
277 | ||
278 | return 1; | |
279 | } | |
280 | __setup("trace_instance=", boot_instance); | |
281 | ||
282 | ||
7bcfaf54 | 283 | static char trace_boot_options_buf[MAX_TRACER_SIZE] __initdata; |
7bcfaf54 SR |
284 | |
285 | static int __init set_trace_boot_options(char *str) | |
286 | { | |
c7dce4c5 | 287 | strscpy(trace_boot_options_buf, str, MAX_TRACER_SIZE); |
1d02b444 | 288 | return 1; |
7bcfaf54 SR |
289 | } |
290 | __setup("trace_options=", set_trace_boot_options); | |
291 | ||
e1e232ca SR |
292 | static char trace_boot_clock_buf[MAX_TRACER_SIZE] __initdata; |
293 | static char *trace_boot_clock __initdata; | |
294 | ||
295 | static int __init set_trace_boot_clock(char *str) | |
296 | { | |
c7dce4c5 | 297 | strscpy(trace_boot_clock_buf, str, MAX_TRACER_SIZE); |
e1e232ca | 298 | trace_boot_clock = trace_boot_clock_buf; |
1d02b444 | 299 | return 1; |
e1e232ca SR |
300 | } |
301 | __setup("trace_clock=", set_trace_boot_clock); | |
302 | ||
0daa2302 SRRH |
303 | static int __init set_tracepoint_printk(char *str) |
304 | { | |
3203ce39 JY |
305 | /* Ignore the "tp_printk_stop_on_boot" param */ |
306 | if (*str == '_') | |
307 | return 0; | |
308 | ||
0daa2302 SRRH |
309 | if ((strcmp(str, "=0") != 0 && strcmp(str, "=off") != 0)) |
310 | tracepoint_printk = 1; | |
311 | return 1; | |
312 | } | |
313 | __setup("tp_printk", set_tracepoint_printk); | |
de7edd31 | 314 | |
f3860136 SRV |
315 | static int __init set_tracepoint_printk_stop(char *str) |
316 | { | |
317 | tracepoint_printk_stop_on_boot = true; | |
318 | return 1; | |
319 | } | |
320 | __setup("tp_printk_stop_on_boot", set_tracepoint_printk_stop); | |
321 | ||
a5a1d1c2 | 322 | unsigned long long ns2usecs(u64 nsec) |
bc0c38d1 SR |
323 | { |
324 | nsec += 500; | |
325 | do_div(nsec, 1000); | |
326 | return nsec; | |
327 | } | |
328 | ||
8ab7a2b7 TZ |
329 | static void |
330 | trace_process_export(struct trace_export *export, | |
331 | struct ring_buffer_event *event, int flag) | |
332 | { | |
333 | struct trace_entry *entry; | |
334 | unsigned int size = 0; | |
335 | ||
336 | if (export->flags & flag) { | |
337 | entry = ring_buffer_event_data(event); | |
338 | size = ring_buffer_event_length(event); | |
339 | export->write(export, entry, size); | |
340 | } | |
341 | } | |
342 | ||
343 | static DEFINE_MUTEX(ftrace_export_lock); | |
344 | ||
345 | static struct trace_export __rcu *ftrace_exports_list __read_mostly; | |
346 | ||
347 | static DEFINE_STATIC_KEY_FALSE(trace_function_exports_enabled); | |
348 | static DEFINE_STATIC_KEY_FALSE(trace_event_exports_enabled); | |
458999c6 | 349 | static DEFINE_STATIC_KEY_FALSE(trace_marker_exports_enabled); |
8ab7a2b7 TZ |
350 | |
351 | static inline void ftrace_exports_enable(struct trace_export *export) | |
352 | { | |
353 | if (export->flags & TRACE_EXPORT_FUNCTION) | |
354 | static_branch_inc(&trace_function_exports_enabled); | |
355 | ||
356 | if (export->flags & TRACE_EXPORT_EVENT) | |
357 | static_branch_inc(&trace_event_exports_enabled); | |
458999c6 TZ |
358 | |
359 | if (export->flags & TRACE_EXPORT_MARKER) | |
360 | static_branch_inc(&trace_marker_exports_enabled); | |
8ab7a2b7 TZ |
361 | } |
362 | ||
363 | static inline void ftrace_exports_disable(struct trace_export *export) | |
364 | { | |
365 | if (export->flags & TRACE_EXPORT_FUNCTION) | |
366 | static_branch_dec(&trace_function_exports_enabled); | |
367 | ||
368 | if (export->flags & TRACE_EXPORT_EVENT) | |
369 | static_branch_dec(&trace_event_exports_enabled); | |
458999c6 TZ |
370 | |
371 | if (export->flags & TRACE_EXPORT_MARKER) | |
372 | static_branch_dec(&trace_marker_exports_enabled); | |
8ab7a2b7 TZ |
373 | } |
374 | ||
375 | static void ftrace_exports(struct ring_buffer_event *event, int flag) | |
376 | { | |
377 | struct trace_export *export; | |
378 | ||
379 | preempt_disable_notrace(); | |
380 | ||
381 | export = rcu_dereference_raw_check(ftrace_exports_list); | |
382 | while (export) { | |
383 | trace_process_export(export, event, flag); | |
384 | export = rcu_dereference_raw_check(export->next); | |
385 | } | |
386 | ||
387 | preempt_enable_notrace(); | |
388 | } | |
389 | ||
390 | static inline void | |
391 | add_trace_export(struct trace_export **list, struct trace_export *export) | |
392 | { | |
393 | rcu_assign_pointer(export->next, *list); | |
394 | /* | |
395 | * We are entering export into the list but another | |
396 | * CPU might be walking that list. We need to make sure | |
397 | * the export->next pointer is valid before another CPU sees | |
398 | * the export pointer included into the list. | |
399 | */ | |
400 | rcu_assign_pointer(*list, export); | |
401 | } | |
402 | ||
403 | static inline int | |
404 | rm_trace_export(struct trace_export **list, struct trace_export *export) | |
405 | { | |
406 | struct trace_export **p; | |
407 | ||
408 | for (p = list; *p != NULL; p = &(*p)->next) | |
409 | if (*p == export) | |
410 | break; | |
411 | ||
412 | if (*p != export) | |
413 | return -1; | |
414 | ||
415 | rcu_assign_pointer(*p, (*p)->next); | |
416 | ||
417 | return 0; | |
418 | } | |
419 | ||
420 | static inline void | |
421 | add_ftrace_export(struct trace_export **list, struct trace_export *export) | |
422 | { | |
423 | ftrace_exports_enable(export); | |
424 | ||
425 | add_trace_export(list, export); | |
426 | } | |
427 | ||
428 | static inline int | |
429 | rm_ftrace_export(struct trace_export **list, struct trace_export *export) | |
430 | { | |
431 | int ret; | |
432 | ||
433 | ret = rm_trace_export(list, export); | |
434 | ftrace_exports_disable(export); | |
435 | ||
436 | return ret; | |
437 | } | |
438 | ||
439 | int register_ftrace_export(struct trace_export *export) | |
440 | { | |
441 | if (WARN_ON_ONCE(!export->write)) | |
442 | return -1; | |
443 | ||
444 | mutex_lock(&ftrace_export_lock); | |
445 | ||
446 | add_ftrace_export(&ftrace_exports_list, export); | |
447 | ||
448 | mutex_unlock(&ftrace_export_lock); | |
449 | ||
450 | return 0; | |
451 | } | |
452 | EXPORT_SYMBOL_GPL(register_ftrace_export); | |
453 | ||
454 | int unregister_ftrace_export(struct trace_export *export) | |
455 | { | |
456 | int ret; | |
457 | ||
458 | mutex_lock(&ftrace_export_lock); | |
459 | ||
460 | ret = rm_ftrace_export(&ftrace_exports_list, export); | |
461 | ||
462 | mutex_unlock(&ftrace_export_lock); | |
463 | ||
464 | return ret; | |
465 | } | |
466 | EXPORT_SYMBOL_GPL(unregister_ftrace_export); | |
467 | ||
983f938a SRRH |
468 | /* trace_flags holds trace_options default values */ |
469 | #define TRACE_DEFAULT_FLAGS \ | |
470 | (FUNCTION_DEFAULT_FLAGS | \ | |
471 | TRACE_ITER_PRINT_PARENT | TRACE_ITER_PRINTK | \ | |
472 | TRACE_ITER_ANNOTATE | TRACE_ITER_CONTEXT_INFO | \ | |
473 | TRACE_ITER_RECORD_CMD | TRACE_ITER_OVERWRITE | \ | |
99e22ce7 SRV |
474 | TRACE_ITER_IRQ_INFO | TRACE_ITER_MARKERS | \ |
475 | TRACE_ITER_HASH_PTR) | |
983f938a | 476 | |
16270145 SRRH |
477 | /* trace_options that are only supported by global_trace */ |
478 | #define TOP_LEVEL_TRACE_FLAGS (TRACE_ITER_PRINTK | \ | |
479 | TRACE_ITER_PRINTK_MSGONLY | TRACE_ITER_RECORD_CMD) | |
480 | ||
20550622 SRRH |
481 | /* trace_flags that are default zero for instances */ |
482 | #define ZEROED_TRACE_FLAGS \ | |
1e10486f | 483 | (TRACE_ITER_EVENT_FORK | TRACE_ITER_FUNC_FORK) |
16270145 | 484 | |
4fcdae83 | 485 | /* |
67d04bb2 JF |
486 | * The global_trace is the descriptor that holds the top-level tracing |
487 | * buffers for the live tracing. | |
4fcdae83 | 488 | */ |
983f938a SRRH |
489 | static struct trace_array global_trace = { |
490 | .trace_flags = TRACE_DEFAULT_FLAGS, | |
491 | }; | |
bc0c38d1 | 492 | |
ae63b31e | 493 | LIST_HEAD(ftrace_trace_arrays); |
bc0c38d1 | 494 | |
ff451961 SRRH |
495 | int trace_array_get(struct trace_array *this_tr) |
496 | { | |
497 | struct trace_array *tr; | |
498 | int ret = -ENODEV; | |
499 | ||
500 | mutex_lock(&trace_types_lock); | |
501 | list_for_each_entry(tr, &ftrace_trace_arrays, list) { | |
502 | if (tr == this_tr) { | |
503 | tr->ref++; | |
504 | ret = 0; | |
505 | break; | |
506 | } | |
507 | } | |
508 | mutex_unlock(&trace_types_lock); | |
509 | ||
510 | return ret; | |
511 | } | |
512 | ||
513 | static void __trace_array_put(struct trace_array *this_tr) | |
514 | { | |
515 | WARN_ON(!this_tr->ref); | |
516 | this_tr->ref--; | |
517 | } | |
518 | ||
28879787 DI |
519 | /** |
520 | * trace_array_put - Decrement the reference counter for this trace array. | |
557d50e7 | 521 | * @this_tr : pointer to the trace array |
28879787 DI |
522 | * |
523 | * NOTE: Use this when we no longer need the trace array returned by | |
524 | * trace_array_get_by_name(). This ensures the trace array can be later | |
525 | * destroyed. | |
526 | * | |
527 | */ | |
ff451961 SRRH |
528 | void trace_array_put(struct trace_array *this_tr) |
529 | { | |
28879787 DI |
530 | if (!this_tr) |
531 | return; | |
532 | ||
ff451961 SRRH |
533 | mutex_lock(&trace_types_lock); |
534 | __trace_array_put(this_tr); | |
535 | mutex_unlock(&trace_types_lock); | |
536 | } | |
28879787 | 537 | EXPORT_SYMBOL_GPL(trace_array_put); |
ff451961 | 538 | |
8530dec6 SRV |
539 | int tracing_check_open_get_tr(struct trace_array *tr) |
540 | { | |
17911ff3 SRV |
541 | int ret; |
542 | ||
543 | ret = security_locked_down(LOCKDOWN_TRACEFS); | |
544 | if (ret) | |
545 | return ret; | |
546 | ||
8530dec6 SRV |
547 | if (tracing_disabled) |
548 | return -ENODEV; | |
549 | ||
550 | if (tr && trace_array_get(tr) < 0) | |
551 | return -ENODEV; | |
552 | ||
553 | return 0; | |
554 | } | |
555 | ||
2425bcb9 | 556 | int call_filter_check_discard(struct trace_event_call *call, void *rec, |
13292494 | 557 | struct trace_buffer *buffer, |
f306cc82 TZ |
558 | struct ring_buffer_event *event) |
559 | { | |
560 | if (unlikely(call->flags & TRACE_EVENT_FL_FILTERED) && | |
561 | !filter_match_preds(call->filter, rec)) { | |
0fc1b09f | 562 | __trace_event_discard_commit(buffer, event); |
f306cc82 TZ |
563 | return 1; |
564 | } | |
565 | ||
566 | return 0; | |
eb02ce01 TZ |
567 | } |
568 | ||
d8275c45 SR |
569 | /** |
570 | * trace_find_filtered_pid - check if a pid exists in a filtered_pid list | |
571 | * @filtered_pids: The list of pids to check | |
572 | * @search_pid: The PID to find in @filtered_pids | |
573 | * | |
f2cc020d | 574 | * Returns true if @search_pid is found in @filtered_pids, and false otherwise. |
d8275c45 SR |
575 | */ |
576 | bool | |
577 | trace_find_filtered_pid(struct trace_pid_list *filtered_pids, pid_t search_pid) | |
578 | { | |
6954e415 | 579 | return trace_pid_list_is_set(filtered_pids, search_pid); |
d8275c45 SR |
580 | } |
581 | ||
582 | /** | |
583 | * trace_ignore_this_task - should a task be ignored for tracing | |
584 | * @filtered_pids: The list of pids to check | |
b3ca59f6 | 585 | * @filtered_no_pids: The list of pids not to be traced |
d8275c45 SR |
586 | * @task: The task that should be ignored if not filtered |
587 | * | |
588 | * Checks if @task should be traced or not from @filtered_pids. | |
589 | * Returns true if @task should *NOT* be traced. | |
590 | * Returns false if @task should be traced. | |
591 | */ | |
592 | bool | |
b3b1e6ed SRV |
593 | trace_ignore_this_task(struct trace_pid_list *filtered_pids, |
594 | struct trace_pid_list *filtered_no_pids, | |
595 | struct task_struct *task) | |
d8275c45 SR |
596 | { |
597 | /* | |
f2cc020d | 598 | * If filtered_no_pids is not empty, and the task's pid is listed |
b3b1e6ed SRV |
599 | * in filtered_no_pids, then return true. |
600 | * Otherwise, if filtered_pids is empty, that means we can | |
601 | * trace all tasks. If it has content, then only trace pids | |
602 | * within filtered_pids. | |
d8275c45 | 603 | */ |
d8275c45 | 604 | |
b3b1e6ed SRV |
605 | return (filtered_pids && |
606 | !trace_find_filtered_pid(filtered_pids, task->pid)) || | |
607 | (filtered_no_pids && | |
608 | trace_find_filtered_pid(filtered_no_pids, task->pid)); | |
d8275c45 SR |
609 | } |
610 | ||
611 | /** | |
f08367b3 | 612 | * trace_filter_add_remove_task - Add or remove a task from a pid_list |
d8275c45 SR |
613 | * @pid_list: The list to modify |
614 | * @self: The current task for fork or NULL for exit | |
615 | * @task: The task to add or remove | |
616 | * | |
617 | * If adding a task, if @self is defined, the task is only added if @self | |
618 | * is also included in @pid_list. This happens on fork and tasks should | |
619 | * only be added when the parent is listed. If @self is NULL, then the | |
620 | * @task pid will be removed from the list, which would happen on exit | |
621 | * of a task. | |
622 | */ | |
623 | void trace_filter_add_remove_task(struct trace_pid_list *pid_list, | |
624 | struct task_struct *self, | |
625 | struct task_struct *task) | |
626 | { | |
627 | if (!pid_list) | |
628 | return; | |
629 | ||
630 | /* For forks, we only add if the forking task is listed */ | |
631 | if (self) { | |
632 | if (!trace_find_filtered_pid(pid_list, self->pid)) | |
633 | return; | |
634 | } | |
635 | ||
d8275c45 SR |
636 | /* "self" is set for forks, and NULL for exits */ |
637 | if (self) | |
6954e415 | 638 | trace_pid_list_set(pid_list, task->pid); |
d8275c45 | 639 | else |
6954e415 | 640 | trace_pid_list_clear(pid_list, task->pid); |
d8275c45 SR |
641 | } |
642 | ||
5cc8976b SRRH |
643 | /** |
644 | * trace_pid_next - Used for seq_file to get to the next pid of a pid_list | |
645 | * @pid_list: The pid list to show | |
646 | * @v: The last pid that was shown (+1 the actual pid to let zero be displayed) | |
647 | * @pos: The position of the file | |
648 | * | |
649 | * This is used by the seq_file "next" operation to iterate the pids | |
650 | * listed in a trace_pid_list structure. | |
651 | * | |
652 | * Returns the pid+1 as we want to display pid of zero, but NULL would | |
653 | * stop the iteration. | |
654 | */ | |
655 | void *trace_pid_next(struct trace_pid_list *pid_list, void *v, loff_t *pos) | |
656 | { | |
6954e415 SRV |
657 | long pid = (unsigned long)v; |
658 | unsigned int next; | |
5cc8976b SRRH |
659 | |
660 | (*pos)++; | |
661 | ||
f2cc020d | 662 | /* pid already is +1 of the actual previous bit */ |
6954e415 SRV |
663 | if (trace_pid_list_next(pid_list, pid, &next) < 0) |
664 | return NULL; | |
5cc8976b | 665 | |
6954e415 | 666 | pid = next; |
5cc8976b | 667 | |
6954e415 SRV |
668 | /* Return pid + 1 to allow zero to be represented */ |
669 | return (void *)(pid + 1); | |
5cc8976b SRRH |
670 | } |
671 | ||
672 | /** | |
673 | * trace_pid_start - Used for seq_file to start reading pid lists | |
674 | * @pid_list: The pid list to show | |
675 | * @pos: The position of the file | |
676 | * | |
677 | * This is used by seq_file "start" operation to start the iteration | |
678 | * of listing pids. | |
679 | * | |
680 | * Returns the pid+1 as we want to display pid of zero, but NULL would | |
681 | * stop the iteration. | |
682 | */ | |
683 | void *trace_pid_start(struct trace_pid_list *pid_list, loff_t *pos) | |
684 | { | |
685 | unsigned long pid; | |
6954e415 | 686 | unsigned int first; |
5cc8976b SRRH |
687 | loff_t l = 0; |
688 | ||
6954e415 | 689 | if (trace_pid_list_first(pid_list, &first) < 0) |
5cc8976b SRRH |
690 | return NULL; |
691 | ||
6954e415 SRV |
692 | pid = first; |
693 | ||
5cc8976b SRRH |
694 | /* Return pid + 1 so that zero can be the exit value */ |
695 | for (pid++; pid && l < *pos; | |
696 | pid = (unsigned long)trace_pid_next(pid_list, (void *)pid, &l)) | |
697 | ; | |
698 | return (void *)pid; | |
699 | } | |
700 | ||
701 | /** | |
702 | * trace_pid_show - show the current pid in seq_file processing | |
703 | * @m: The seq_file structure to write into | |
704 | * @v: A void pointer of the pid (+1) value to display | |
705 | * | |
706 | * Can be directly used by seq_file operations to display the current | |
707 | * pid value. | |
708 | */ | |
709 | int trace_pid_show(struct seq_file *m, void *v) | |
710 | { | |
711 | unsigned long pid = (unsigned long)v - 1; | |
712 | ||
713 | seq_printf(m, "%lu\n", pid); | |
714 | return 0; | |
715 | } | |
716 | ||
76c813e2 SRRH |
717 | /* 128 should be much more than enough */ |
718 | #define PID_BUF_SIZE 127 | |
719 | ||
720 | int trace_pid_write(struct trace_pid_list *filtered_pids, | |
721 | struct trace_pid_list **new_pid_list, | |
722 | const char __user *ubuf, size_t cnt) | |
723 | { | |
724 | struct trace_pid_list *pid_list; | |
725 | struct trace_parser parser; | |
726 | unsigned long val; | |
727 | int nr_pids = 0; | |
728 | ssize_t read = 0; | |
6954e415 | 729 | ssize_t ret; |
76c813e2 SRRH |
730 | loff_t pos; |
731 | pid_t pid; | |
732 | ||
733 | if (trace_parser_get_init(&parser, PID_BUF_SIZE + 1)) | |
734 | return -ENOMEM; | |
735 | ||
736 | /* | |
737 | * Always recreate a new array. The write is an all or nothing | |
738 | * operation. Always create a new array when adding new pids by | |
739 | * the user. If the operation fails, then the current list is | |
740 | * not modified. | |
741 | */ | |
6954e415 | 742 | pid_list = trace_pid_list_alloc(); |
91862cc7 WW |
743 | if (!pid_list) { |
744 | trace_parser_put(&parser); | |
76c813e2 | 745 | return -ENOMEM; |
91862cc7 | 746 | } |
76c813e2 | 747 | |
76c813e2 SRRH |
748 | if (filtered_pids) { |
749 | /* copy the current bits to the new max */ | |
6954e415 SRV |
750 | ret = trace_pid_list_first(filtered_pids, &pid); |
751 | while (!ret) { | |
752 | trace_pid_list_set(pid_list, pid); | |
753 | ret = trace_pid_list_next(filtered_pids, pid + 1, &pid); | |
76c813e2 SRRH |
754 | nr_pids++; |
755 | } | |
756 | } | |
757 | ||
6954e415 | 758 | ret = 0; |
76c813e2 SRRH |
759 | while (cnt > 0) { |
760 | ||
761 | pos = 0; | |
762 | ||
763 | ret = trace_get_user(&parser, ubuf, cnt, &pos); | |
b27f266f | 764 | if (ret < 0) |
76c813e2 SRRH |
765 | break; |
766 | ||
767 | read += ret; | |
768 | ubuf += ret; | |
769 | cnt -= ret; | |
770 | ||
b27f266f WY |
771 | if (!trace_parser_loaded(&parser)) |
772 | break; | |
773 | ||
76c813e2 SRRH |
774 | ret = -EINVAL; |
775 | if (kstrtoul(parser.buffer, 0, &val)) | |
776 | break; | |
76c813e2 SRRH |
777 | |
778 | pid = (pid_t)val; | |
779 | ||
6954e415 SRV |
780 | if (trace_pid_list_set(pid_list, pid) < 0) { |
781 | ret = -1; | |
782 | break; | |
783 | } | |
76c813e2 SRRH |
784 | nr_pids++; |
785 | ||
786 | trace_parser_clear(&parser); | |
787 | ret = 0; | |
788 | } | |
789 | trace_parser_put(&parser); | |
790 | ||
791 | if (ret < 0) { | |
6954e415 | 792 | trace_pid_list_free(pid_list); |
76c813e2 SRRH |
793 | return ret; |
794 | } | |
795 | ||
796 | if (!nr_pids) { | |
797 | /* Cleared the list of pids */ | |
6954e415 | 798 | trace_pid_list_free(pid_list); |
76c813e2 SRRH |
799 | pid_list = NULL; |
800 | } | |
801 | ||
802 | *new_pid_list = pid_list; | |
803 | ||
804 | return read; | |
805 | } | |
806 | ||
1c5eb448 | 807 | static u64 buffer_ftrace_now(struct array_buffer *buf, int cpu) |
37886f6a SR |
808 | { |
809 | u64 ts; | |
810 | ||
811 | /* Early boot up does not have a buffer yet */ | |
9457158b | 812 | if (!buf->buffer) |
37886f6a SR |
813 | return trace_clock_local(); |
814 | ||
f3ef7202 | 815 | ts = ring_buffer_time_stamp(buf->buffer); |
9457158b | 816 | ring_buffer_normalize_time_stamp(buf->buffer, cpu, &ts); |
37886f6a SR |
817 | |
818 | return ts; | |
819 | } | |
bc0c38d1 | 820 | |
a5a1d1c2 | 821 | u64 ftrace_now(int cpu) |
9457158b | 822 | { |
1c5eb448 | 823 | return buffer_ftrace_now(&global_trace.array_buffer, cpu); |
9457158b AL |
824 | } |
825 | ||
10246fa3 | 826 | /** |
b3ca59f6 | 827 | * tracing_is_enabled - Show if global_trace has been enabled |
10246fa3 SRRH |
828 | * |
829 | * Shows if the global trace has been enabled or not. It uses the | |
830 | * mirror flag "buffer_disabled" to be used in fast paths such as for | |
831 | * the irqsoff tracer. But it may be inaccurate due to races. If you | |
832 | * need to know the accurate state, use tracing_is_on() which is a little | |
833 | * slower, but accurate. | |
834 | */ | |
9036990d SR |
835 | int tracing_is_enabled(void) |
836 | { | |
10246fa3 SRRH |
837 | /* |
838 | * For quick access (irqsoff uses this in fast path), just | |
839 | * return the mirror variable of the state of the ring buffer. | |
840 | * It's a little racy, but we don't really care. | |
841 | */ | |
842 | smp_rmb(); | |
843 | return !global_trace.buffer_disabled; | |
9036990d SR |
844 | } |
845 | ||
4fcdae83 | 846 | /* |
3928a8a2 SR |
847 | * trace_buf_size is the size in bytes that is allocated |
848 | * for a buffer. Note, the number of bytes is always rounded | |
849 | * to page size. | |
3f5a54e3 SR |
850 | * |
851 | * This number is purposely set to a low number of 16384. | |
852 | * If the dump on oops happens, it will be much appreciated | |
853 | * to not have to wait for all that output. Anyway this can be | |
854 | * boot time and run time configurable. | |
4fcdae83 | 855 | */ |
3928a8a2 | 856 | #define TRACE_BUF_SIZE_DEFAULT 1441792UL /* 16384 * 88 (sizeof(entry)) */ |
3f5a54e3 | 857 | |
3928a8a2 | 858 | static unsigned long trace_buf_size = TRACE_BUF_SIZE_DEFAULT; |
bc0c38d1 | 859 | |
4fcdae83 | 860 | /* trace_types holds a link list of available tracers. */ |
bc0c38d1 | 861 | static struct tracer *trace_types __read_mostly; |
4fcdae83 | 862 | |
4fcdae83 SR |
863 | /* |
864 | * trace_types_lock is used to protect the trace_types list. | |
4fcdae83 | 865 | */ |
a8227415 | 866 | DEFINE_MUTEX(trace_types_lock); |
4fcdae83 | 867 | |
7e53bd42 LJ |
868 | /* |
869 | * serialize the access of the ring buffer | |
870 | * | |
871 | * ring buffer serializes readers, but it is low level protection. | |
872 | * The validity of the events (which returns by ring_buffer_peek() ..etc) | |
873 | * are not protected by ring buffer. | |
874 | * | |
875 | * The content of events may become garbage if we allow other process consumes | |
876 | * these events concurrently: | |
877 | * A) the page of the consumed events may become a normal page | |
f2cc020d | 878 | * (not reader page) in ring buffer, and this page will be rewritten |
7e53bd42 LJ |
879 | * by events producer. |
880 | * B) The page of the consumed events may become a page for splice_read, | |
881 | * and this page will be returned to system. | |
882 | * | |
883 | * These primitives allow multi process access to different cpu ring buffer | |
884 | * concurrently. | |
885 | * | |
886 | * These primitives don't distinguish read-only and read-consume access. | |
887 | * Multi read-only access are also serialized. | |
888 | */ | |
889 | ||
890 | #ifdef CONFIG_SMP | |
891 | static DECLARE_RWSEM(all_cpu_access_lock); | |
892 | static DEFINE_PER_CPU(struct mutex, cpu_access_lock); | |
893 | ||
894 | static inline void trace_access_lock(int cpu) | |
895 | { | |
ae3b5093 | 896 | if (cpu == RING_BUFFER_ALL_CPUS) { |
7e53bd42 LJ |
897 | /* gain it for accessing the whole ring buffer. */ |
898 | down_write(&all_cpu_access_lock); | |
899 | } else { | |
900 | /* gain it for accessing a cpu ring buffer. */ | |
901 | ||
ae3b5093 | 902 | /* Firstly block other trace_access_lock(RING_BUFFER_ALL_CPUS). */ |
7e53bd42 LJ |
903 | down_read(&all_cpu_access_lock); |
904 | ||
905 | /* Secondly block other access to this @cpu ring buffer. */ | |
906 | mutex_lock(&per_cpu(cpu_access_lock, cpu)); | |
907 | } | |
908 | } | |
909 | ||
910 | static inline void trace_access_unlock(int cpu) | |
911 | { | |
ae3b5093 | 912 | if (cpu == RING_BUFFER_ALL_CPUS) { |
7e53bd42 LJ |
913 | up_write(&all_cpu_access_lock); |
914 | } else { | |
915 | mutex_unlock(&per_cpu(cpu_access_lock, cpu)); | |
916 | up_read(&all_cpu_access_lock); | |
917 | } | |
918 | } | |
919 | ||
920 | static inline void trace_access_lock_init(void) | |
921 | { | |
922 | int cpu; | |
923 | ||
924 | for_each_possible_cpu(cpu) | |
925 | mutex_init(&per_cpu(cpu_access_lock, cpu)); | |
926 | } | |
927 | ||
928 | #else | |
929 | ||
930 | static DEFINE_MUTEX(access_lock); | |
931 | ||
932 | static inline void trace_access_lock(int cpu) | |
933 | { | |
934 | (void)cpu; | |
935 | mutex_lock(&access_lock); | |
936 | } | |
937 | ||
938 | static inline void trace_access_unlock(int cpu) | |
939 | { | |
940 | (void)cpu; | |
941 | mutex_unlock(&access_lock); | |
942 | } | |
943 | ||
944 | static inline void trace_access_lock_init(void) | |
945 | { | |
946 | } | |
947 | ||
948 | #endif | |
949 | ||
d78a4614 | 950 | #ifdef CONFIG_STACKTRACE |
13292494 | 951 | static void __ftrace_trace_stack(struct trace_buffer *buffer, |
36590c50 SAS |
952 | unsigned int trace_ctx, |
953 | int skip, struct pt_regs *regs); | |
2d34f489 | 954 | static inline void ftrace_trace_stack(struct trace_array *tr, |
13292494 | 955 | struct trace_buffer *buffer, |
36590c50 SAS |
956 | unsigned int trace_ctx, |
957 | int skip, struct pt_regs *regs); | |
ca475e83 | 958 | |
d78a4614 | 959 | #else |
13292494 | 960 | static inline void __ftrace_trace_stack(struct trace_buffer *buffer, |
36590c50 SAS |
961 | unsigned int trace_ctx, |
962 | int skip, struct pt_regs *regs) | |
d78a4614 SRRH |
963 | { |
964 | } | |
2d34f489 | 965 | static inline void ftrace_trace_stack(struct trace_array *tr, |
13292494 | 966 | struct trace_buffer *buffer, |
36590c50 SAS |
967 | unsigned long trace_ctx, |
968 | int skip, struct pt_regs *regs) | |
ca475e83 SRRH |
969 | { |
970 | } | |
971 | ||
d78a4614 SRRH |
972 | #endif |
973 | ||
3e9a8aad SRRH |
974 | static __always_inline void |
975 | trace_event_setup(struct ring_buffer_event *event, | |
36590c50 | 976 | int type, unsigned int trace_ctx) |
3e9a8aad SRRH |
977 | { |
978 | struct trace_entry *ent = ring_buffer_event_data(event); | |
979 | ||
36590c50 | 980 | tracing_generic_entry_update(ent, type, trace_ctx); |
3e9a8aad SRRH |
981 | } |
982 | ||
983 | static __always_inline struct ring_buffer_event * | |
13292494 | 984 | __trace_buffer_lock_reserve(struct trace_buffer *buffer, |
3e9a8aad SRRH |
985 | int type, |
986 | unsigned long len, | |
36590c50 | 987 | unsigned int trace_ctx) |
3e9a8aad SRRH |
988 | { |
989 | struct ring_buffer_event *event; | |
990 | ||
991 | event = ring_buffer_lock_reserve(buffer, len); | |
992 | if (event != NULL) | |
36590c50 | 993 | trace_event_setup(event, type, trace_ctx); |
3e9a8aad SRRH |
994 | |
995 | return event; | |
996 | } | |
997 | ||
2290f2c5 | 998 | void tracer_tracing_on(struct trace_array *tr) |
10246fa3 | 999 | { |
1c5eb448 SRV |
1000 | if (tr->array_buffer.buffer) |
1001 | ring_buffer_record_on(tr->array_buffer.buffer); | |
10246fa3 SRRH |
1002 | /* |
1003 | * This flag is looked at when buffers haven't been allocated | |
1004 | * yet, or by some tracers (like irqsoff), that just want to | |
1005 | * know if the ring buffer has been disabled, but it can handle | |
1006 | * races of where it gets disabled but we still do a record. | |
1007 | * As the check is in the fast path of the tracers, it is more | |
1008 | * important to be fast than accurate. | |
1009 | */ | |
1010 | tr->buffer_disabled = 0; | |
1011 | /* Make the flag seen by readers */ | |
1012 | smp_wmb(); | |
1013 | } | |
1014 | ||
499e5470 SR |
1015 | /** |
1016 | * tracing_on - enable tracing buffers | |
1017 | * | |
1018 | * This function enables tracing buffers that may have been | |
1019 | * disabled with tracing_off. | |
1020 | */ | |
1021 | void tracing_on(void) | |
1022 | { | |
10246fa3 | 1023 | tracer_tracing_on(&global_trace); |
499e5470 SR |
1024 | } |
1025 | EXPORT_SYMBOL_GPL(tracing_on); | |
1026 | ||
52ffabe3 SRRH |
1027 | |
1028 | static __always_inline void | |
13292494 | 1029 | __buffer_unlock_commit(struct trace_buffer *buffer, struct ring_buffer_event *event) |
52ffabe3 | 1030 | { |
d914ba37 | 1031 | __this_cpu_write(trace_taskinfo_save, true); |
52ffabe3 SRRH |
1032 | |
1033 | /* If this is the temp buffer, we need to commit fully */ | |
1034 | if (this_cpu_read(trace_buffered_event) == event) { | |
1035 | /* Length is in event->array[0] */ | |
1036 | ring_buffer_write(buffer, event->array[0], &event->array[1]); | |
1037 | /* Release the temp buffer */ | |
1038 | this_cpu_dec(trace_buffered_event_cnt); | |
6c536d76 SRV |
1039 | /* ring_buffer_unlock_commit() enables preemption */ |
1040 | preempt_enable_notrace(); | |
52ffabe3 | 1041 | } else |
04aabc32 | 1042 | ring_buffer_unlock_commit(buffer); |
52ffabe3 SRRH |
1043 | } |
1044 | ||
d503b8f7 SRG |
1045 | int __trace_array_puts(struct trace_array *tr, unsigned long ip, |
1046 | const char *str, int size) | |
09ae7234 SRRH |
1047 | { |
1048 | struct ring_buffer_event *event; | |
13292494 | 1049 | struct trace_buffer *buffer; |
09ae7234 | 1050 | struct print_entry *entry; |
36590c50 | 1051 | unsigned int trace_ctx; |
09ae7234 | 1052 | int alloc; |
8abfb872 | 1053 | |
d503b8f7 | 1054 | if (!(tr->trace_flags & TRACE_ITER_PRINTK)) |
f0160a5a J |
1055 | return 0; |
1056 | ||
ac9d2cb1 SRG |
1057 | if (unlikely(tracing_selftest_running && tr == &global_trace)) |
1058 | return 0; | |
1059 | ||
1060 | if (unlikely(tracing_disabled)) | |
3132e107 SRRH |
1061 | return 0; |
1062 | ||
09ae7234 SRRH |
1063 | alloc = sizeof(*entry) + size + 2; /* possible \n added */ |
1064 | ||
36590c50 | 1065 | trace_ctx = tracing_gen_ctx(); |
d503b8f7 | 1066 | buffer = tr->array_buffer.buffer; |
82d1b815 | 1067 | ring_buffer_nest_start(buffer); |
36590c50 SAS |
1068 | event = __trace_buffer_lock_reserve(buffer, TRACE_PRINT, alloc, |
1069 | trace_ctx); | |
82d1b815 SRV |
1070 | if (!event) { |
1071 | size = 0; | |
1072 | goto out; | |
1073 | } | |
09ae7234 SRRH |
1074 | |
1075 | entry = ring_buffer_event_data(event); | |
1076 | entry->ip = ip; | |
1077 | ||
1078 | memcpy(&entry->buf, str, size); | |
1079 | ||
1080 | /* Add a newline if necessary */ | |
1081 | if (entry->buf[size - 1] != '\n') { | |
1082 | entry->buf[size] = '\n'; | |
1083 | entry->buf[size + 1] = '\0'; | |
1084 | } else | |
1085 | entry->buf[size] = '\0'; | |
1086 | ||
1087 | __buffer_unlock_commit(buffer, event); | |
d503b8f7 | 1088 | ftrace_trace_stack(tr, buffer, trace_ctx, 4, NULL); |
82d1b815 SRV |
1089 | out: |
1090 | ring_buffer_nest_end(buffer); | |
09ae7234 SRRH |
1091 | return size; |
1092 | } | |
d503b8f7 SRG |
1093 | EXPORT_SYMBOL_GPL(__trace_array_puts); |
1094 | ||
1095 | /** | |
1096 | * __trace_puts - write a constant string into the trace buffer. | |
1097 | * @ip: The address of the caller | |
1098 | * @str: The constant string to write | |
1099 | * @size: The size of the string. | |
1100 | */ | |
1101 | int __trace_puts(unsigned long ip, const char *str, int size) | |
1102 | { | |
1103 | return __trace_array_puts(&global_trace, ip, str, size); | |
1104 | } | |
09ae7234 SRRH |
1105 | EXPORT_SYMBOL_GPL(__trace_puts); |
1106 | ||
1107 | /** | |
1108 | * __trace_bputs - write the pointer to a constant string into trace buffer | |
1109 | * @ip: The address of the caller | |
1110 | * @str: The constant string to write to the buffer to | |
1111 | */ | |
1112 | int __trace_bputs(unsigned long ip, const char *str) | |
1113 | { | |
1114 | struct ring_buffer_event *event; | |
13292494 | 1115 | struct trace_buffer *buffer; |
09ae7234 | 1116 | struct bputs_entry *entry; |
36590c50 | 1117 | unsigned int trace_ctx; |
09ae7234 | 1118 | int size = sizeof(struct bputs_entry); |
82d1b815 | 1119 | int ret = 0; |
8abfb872 | 1120 | |
983f938a | 1121 | if (!(global_trace.trace_flags & TRACE_ITER_PRINTK)) |
f0160a5a J |
1122 | return 0; |
1123 | ||
3132e107 SRRH |
1124 | if (unlikely(tracing_selftest_running || tracing_disabled)) |
1125 | return 0; | |
1126 | ||
36590c50 | 1127 | trace_ctx = tracing_gen_ctx(); |
1c5eb448 | 1128 | buffer = global_trace.array_buffer.buffer; |
82d1b815 SRV |
1129 | |
1130 | ring_buffer_nest_start(buffer); | |
3e9a8aad | 1131 | event = __trace_buffer_lock_reserve(buffer, TRACE_BPUTS, size, |
36590c50 | 1132 | trace_ctx); |
09ae7234 | 1133 | if (!event) |
82d1b815 | 1134 | goto out; |
09ae7234 SRRH |
1135 | |
1136 | entry = ring_buffer_event_data(event); | |
1137 | entry->ip = ip; | |
1138 | entry->str = str; | |
1139 | ||
1140 | __buffer_unlock_commit(buffer, event); | |
36590c50 | 1141 | ftrace_trace_stack(&global_trace, buffer, trace_ctx, 4, NULL); |
09ae7234 | 1142 | |
82d1b815 SRV |
1143 | ret = 1; |
1144 | out: | |
1145 | ring_buffer_nest_end(buffer); | |
1146 | return ret; | |
09ae7234 SRRH |
1147 | } |
1148 | EXPORT_SYMBOL_GPL(__trace_bputs); | |
1149 | ||
ad909e21 | 1150 | #ifdef CONFIG_TRACER_SNAPSHOT |
192b7993 ZW |
1151 | static void tracing_snapshot_instance_cond(struct trace_array *tr, |
1152 | void *cond_data) | |
ad909e21 | 1153 | { |
ad909e21 SRRH |
1154 | struct tracer *tracer = tr->current_trace; |
1155 | unsigned long flags; | |
1156 | ||
1b22e382 | 1157 | if (in_nmi()) { |
9d52727f SRG |
1158 | trace_array_puts(tr, "*** SNAPSHOT CALLED FROM NMI CONTEXT ***\n"); |
1159 | trace_array_puts(tr, "*** snapshot is being ignored ***\n"); | |
1b22e382 SRRH |
1160 | return; |
1161 | } | |
1162 | ||
ad909e21 | 1163 | if (!tr->allocated_snapshot) { |
9d52727f SRG |
1164 | trace_array_puts(tr, "*** SNAPSHOT NOT ALLOCATED ***\n"); |
1165 | trace_array_puts(tr, "*** stopping trace here! ***\n"); | |
1166 | tracer_tracing_off(tr); | |
ad909e21 SRRH |
1167 | return; |
1168 | } | |
1169 | ||
1170 | /* Note, snapshot can not be used when the tracer uses it */ | |
1171 | if (tracer->use_max_tr) { | |
9d52727f SRG |
1172 | trace_array_puts(tr, "*** LATENCY TRACER ACTIVE ***\n"); |
1173 | trace_array_puts(tr, "*** Can not use snapshot (sorry) ***\n"); | |
ad909e21 SRRH |
1174 | return; |
1175 | } | |
1176 | ||
1177 | local_irq_save(flags); | |
a35873a0 | 1178 | update_max_tr(tr, current, smp_processor_id(), cond_data); |
ad909e21 SRRH |
1179 | local_irq_restore(flags); |
1180 | } | |
cab50379 | 1181 | |
a35873a0 TZ |
1182 | void tracing_snapshot_instance(struct trace_array *tr) |
1183 | { | |
1184 | tracing_snapshot_instance_cond(tr, NULL); | |
1185 | } | |
1186 | ||
cab50379 | 1187 | /** |
5a93bae2 | 1188 | * tracing_snapshot - take a snapshot of the current buffer. |
cab50379 SRV |
1189 | * |
1190 | * This causes a swap between the snapshot buffer and the current live | |
1191 | * tracing buffer. You can use this to take snapshots of the live | |
1192 | * trace when some condition is triggered, but continue to trace. | |
1193 | * | |
1194 | * Note, make sure to allocate the snapshot with either | |
1195 | * a tracing_snapshot_alloc(), or by doing it manually | |
2455f0e1 | 1196 | * with: echo 1 > /sys/kernel/tracing/snapshot |
cab50379 SRV |
1197 | * |
1198 | * If the snapshot buffer is not allocated, it will stop tracing. | |
1199 | * Basically making a permanent snapshot. | |
1200 | */ | |
1201 | void tracing_snapshot(void) | |
1202 | { | |
1203 | struct trace_array *tr = &global_trace; | |
1204 | ||
1205 | tracing_snapshot_instance(tr); | |
1206 | } | |
1b22e382 | 1207 | EXPORT_SYMBOL_GPL(tracing_snapshot); |
ad909e21 | 1208 | |
a35873a0 TZ |
1209 | /** |
1210 | * tracing_snapshot_cond - conditionally take a snapshot of the current buffer. | |
1211 | * @tr: The tracing instance to snapshot | |
1212 | * @cond_data: The data to be tested conditionally, and possibly saved | |
1213 | * | |
1214 | * This is the same as tracing_snapshot() except that the snapshot is | |
1215 | * conditional - the snapshot will only happen if the | |
1216 | * cond_snapshot.update() implementation receiving the cond_data | |
1217 | * returns true, which means that the trace array's cond_snapshot | |
1218 | * update() operation used the cond_data to determine whether the | |
1219 | * snapshot should be taken, and if it was, presumably saved it along | |
1220 | * with the snapshot. | |
1221 | */ | |
1222 | void tracing_snapshot_cond(struct trace_array *tr, void *cond_data) | |
1223 | { | |
1224 | tracing_snapshot_instance_cond(tr, cond_data); | |
1225 | } | |
1226 | EXPORT_SYMBOL_GPL(tracing_snapshot_cond); | |
1227 | ||
1228 | /** | |
3b57d847 | 1229 | * tracing_cond_snapshot_data - get the user data associated with a snapshot |
a35873a0 TZ |
1230 | * @tr: The tracing instance |
1231 | * | |
1232 | * When the user enables a conditional snapshot using | |
1233 | * tracing_snapshot_cond_enable(), the user-defined cond_data is saved | |
1234 | * with the snapshot. This accessor is used to retrieve it. | |
1235 | * | |
1236 | * Should not be called from cond_snapshot.update(), since it takes | |
1237 | * the tr->max_lock lock, which the code calling | |
1238 | * cond_snapshot.update() has already done. | |
1239 | * | |
1240 | * Returns the cond_data associated with the trace array's snapshot. | |
1241 | */ | |
1242 | void *tracing_cond_snapshot_data(struct trace_array *tr) | |
1243 | { | |
1244 | void *cond_data = NULL; | |
1245 | ||
c0a581d7 | 1246 | local_irq_disable(); |
a35873a0 TZ |
1247 | arch_spin_lock(&tr->max_lock); |
1248 | ||
1249 | if (tr->cond_snapshot) | |
1250 | cond_data = tr->cond_snapshot->cond_data; | |
1251 | ||
1252 | arch_spin_unlock(&tr->max_lock); | |
c0a581d7 | 1253 | local_irq_enable(); |
a35873a0 TZ |
1254 | |
1255 | return cond_data; | |
1256 | } | |
1257 | EXPORT_SYMBOL_GPL(tracing_cond_snapshot_data); | |
1258 | ||
1c5eb448 SRV |
1259 | static int resize_buffer_duplicate_size(struct array_buffer *trace_buf, |
1260 | struct array_buffer *size_buf, int cpu_id); | |
1261 | static void set_buffer_entries(struct array_buffer *buf, unsigned long val); | |
3209cff4 | 1262 | |
2824f503 | 1263 | int tracing_alloc_snapshot_instance(struct trace_array *tr) |
3209cff4 SRRH |
1264 | { |
1265 | int ret; | |
1266 | ||
1267 | if (!tr->allocated_snapshot) { | |
1268 | ||
1269 | /* allocate spare buffer */ | |
1270 | ret = resize_buffer_duplicate_size(&tr->max_buffer, | |
1c5eb448 | 1271 | &tr->array_buffer, RING_BUFFER_ALL_CPUS); |
3209cff4 SRRH |
1272 | if (ret < 0) |
1273 | return ret; | |
1274 | ||
1275 | tr->allocated_snapshot = true; | |
1276 | } | |
1277 | ||
1278 | return 0; | |
1279 | } | |
1280 | ||
ad1438a0 | 1281 | static void free_snapshot(struct trace_array *tr) |
3209cff4 SRRH |
1282 | { |
1283 | /* | |
1284 | * We don't free the ring buffer. instead, resize it because | |
1285 | * The max_tr ring buffer has some state (e.g. ring->clock) and | |
1286 | * we want preserve it. | |
1287 | */ | |
1288 | ring_buffer_resize(tr->max_buffer.buffer, 1, RING_BUFFER_ALL_CPUS); | |
1289 | set_buffer_entries(&tr->max_buffer, 1); | |
1290 | tracing_reset_online_cpus(&tr->max_buffer); | |
1291 | tr->allocated_snapshot = false; | |
1292 | } | |
ad909e21 | 1293 | |
93e31ffb TZ |
1294 | /** |
1295 | * tracing_alloc_snapshot - allocate snapshot buffer. | |
1296 | * | |
1297 | * This only allocates the snapshot buffer if it isn't already | |
1298 | * allocated - it doesn't also take a snapshot. | |
1299 | * | |
1300 | * This is meant to be used in cases where the snapshot buffer needs | |
1301 | * to be set up for events that can't sleep but need to be able to | |
1302 | * trigger a snapshot. | |
1303 | */ | |
1304 | int tracing_alloc_snapshot(void) | |
1305 | { | |
1306 | struct trace_array *tr = &global_trace; | |
1307 | int ret; | |
1308 | ||
2824f503 | 1309 | ret = tracing_alloc_snapshot_instance(tr); |
93e31ffb TZ |
1310 | WARN_ON(ret < 0); |
1311 | ||
1312 | return ret; | |
1313 | } | |
1314 | EXPORT_SYMBOL_GPL(tracing_alloc_snapshot); | |
1315 | ||
ad909e21 | 1316 | /** |
5a93bae2 | 1317 | * tracing_snapshot_alloc - allocate and take a snapshot of the current buffer. |
ad909e21 | 1318 | * |
5a93bae2 | 1319 | * This is similar to tracing_snapshot(), but it will allocate the |
ad909e21 SRRH |
1320 | * snapshot buffer if it isn't already allocated. Use this only |
1321 | * where it is safe to sleep, as the allocation may sleep. | |
1322 | * | |
1323 | * This causes a swap between the snapshot buffer and the current live | |
1324 | * tracing buffer. You can use this to take snapshots of the live | |
1325 | * trace when some condition is triggered, but continue to trace. | |
1326 | */ | |
1327 | void tracing_snapshot_alloc(void) | |
1328 | { | |
ad909e21 SRRH |
1329 | int ret; |
1330 | ||
93e31ffb TZ |
1331 | ret = tracing_alloc_snapshot(); |
1332 | if (ret < 0) | |
3209cff4 | 1333 | return; |
ad909e21 SRRH |
1334 | |
1335 | tracing_snapshot(); | |
1336 | } | |
1b22e382 | 1337 | EXPORT_SYMBOL_GPL(tracing_snapshot_alloc); |
a35873a0 TZ |
1338 | |
1339 | /** | |
1340 | * tracing_snapshot_cond_enable - enable conditional snapshot for an instance | |
1341 | * @tr: The tracing instance | |
1342 | * @cond_data: User data to associate with the snapshot | |
1343 | * @update: Implementation of the cond_snapshot update function | |
1344 | * | |
1345 | * Check whether the conditional snapshot for the given instance has | |
1346 | * already been enabled, or if the current tracer is already using a | |
1347 | * snapshot; if so, return -EBUSY, else create a cond_snapshot and | |
1348 | * save the cond_data and update function inside. | |
1349 | * | |
1350 | * Returns 0 if successful, error otherwise. | |
1351 | */ | |
1352 | int tracing_snapshot_cond_enable(struct trace_array *tr, void *cond_data, | |
1353 | cond_update_fn_t update) | |
1354 | { | |
1355 | struct cond_snapshot *cond_snapshot; | |
1356 | int ret = 0; | |
1357 | ||
1358 | cond_snapshot = kzalloc(sizeof(*cond_snapshot), GFP_KERNEL); | |
1359 | if (!cond_snapshot) | |
1360 | return -ENOMEM; | |
1361 | ||
1362 | cond_snapshot->cond_data = cond_data; | |
1363 | cond_snapshot->update = update; | |
1364 | ||
1365 | mutex_lock(&trace_types_lock); | |
1366 | ||
1367 | ret = tracing_alloc_snapshot_instance(tr); | |
1368 | if (ret) | |
1369 | goto fail_unlock; | |
1370 | ||
1371 | if (tr->current_trace->use_max_tr) { | |
1372 | ret = -EBUSY; | |
1373 | goto fail_unlock; | |
1374 | } | |
1375 | ||
1c347a94 SRV |
1376 | /* |
1377 | * The cond_snapshot can only change to NULL without the | |
1378 | * trace_types_lock. We don't care if we race with it going | |
1379 | * to NULL, but we want to make sure that it's not set to | |
1380 | * something other than NULL when we get here, which we can | |
1381 | * do safely with only holding the trace_types_lock and not | |
1382 | * having to take the max_lock. | |
1383 | */ | |
a35873a0 TZ |
1384 | if (tr->cond_snapshot) { |
1385 | ret = -EBUSY; | |
1386 | goto fail_unlock; | |
1387 | } | |
1388 | ||
c0a581d7 | 1389 | local_irq_disable(); |
a35873a0 TZ |
1390 | arch_spin_lock(&tr->max_lock); |
1391 | tr->cond_snapshot = cond_snapshot; | |
1392 | arch_spin_unlock(&tr->max_lock); | |
c0a581d7 | 1393 | local_irq_enable(); |
a35873a0 TZ |
1394 | |
1395 | mutex_unlock(&trace_types_lock); | |
1396 | ||
1397 | return ret; | |
1398 | ||
1399 | fail_unlock: | |
1400 | mutex_unlock(&trace_types_lock); | |
1401 | kfree(cond_snapshot); | |
1402 | return ret; | |
1403 | } | |
1404 | EXPORT_SYMBOL_GPL(tracing_snapshot_cond_enable); | |
1405 | ||
1406 | /** | |
1407 | * tracing_snapshot_cond_disable - disable conditional snapshot for an instance | |
1408 | * @tr: The tracing instance | |
1409 | * | |
1410 | * Check whether the conditional snapshot for the given instance is | |
1411 | * enabled; if so, free the cond_snapshot associated with it, | |
1412 | * otherwise return -EINVAL. | |
1413 | * | |
1414 | * Returns 0 if successful, error otherwise. | |
1415 | */ | |
1416 | int tracing_snapshot_cond_disable(struct trace_array *tr) | |
1417 | { | |
1418 | int ret = 0; | |
1419 | ||
c0a581d7 | 1420 | local_irq_disable(); |
a35873a0 TZ |
1421 | arch_spin_lock(&tr->max_lock); |
1422 | ||
1423 | if (!tr->cond_snapshot) | |
1424 | ret = -EINVAL; | |
1425 | else { | |
1426 | kfree(tr->cond_snapshot); | |
1427 | tr->cond_snapshot = NULL; | |
1428 | } | |
1429 | ||
1430 | arch_spin_unlock(&tr->max_lock); | |
c0a581d7 | 1431 | local_irq_enable(); |
a35873a0 TZ |
1432 | |
1433 | return ret; | |
1434 | } | |
1435 | EXPORT_SYMBOL_GPL(tracing_snapshot_cond_disable); | |
ad909e21 SRRH |
1436 | #else |
1437 | void tracing_snapshot(void) | |
1438 | { | |
1439 | WARN_ONCE(1, "Snapshot feature not enabled, but internal snapshot used"); | |
1440 | } | |
1b22e382 | 1441 | EXPORT_SYMBOL_GPL(tracing_snapshot); |
a35873a0 TZ |
1442 | void tracing_snapshot_cond(struct trace_array *tr, void *cond_data) |
1443 | { | |
1444 | WARN_ONCE(1, "Snapshot feature not enabled, but internal conditional snapshot used"); | |
1445 | } | |
1446 | EXPORT_SYMBOL_GPL(tracing_snapshot_cond); | |
93e31ffb TZ |
1447 | int tracing_alloc_snapshot(void) |
1448 | { | |
1449 | WARN_ONCE(1, "Snapshot feature not enabled, but snapshot allocation used"); | |
1450 | return -ENODEV; | |
1451 | } | |
1452 | EXPORT_SYMBOL_GPL(tracing_alloc_snapshot); | |
ad909e21 SRRH |
1453 | void tracing_snapshot_alloc(void) |
1454 | { | |
1455 | /* Give warning */ | |
1456 | tracing_snapshot(); | |
1457 | } | |
1b22e382 | 1458 | EXPORT_SYMBOL_GPL(tracing_snapshot_alloc); |
a35873a0 TZ |
1459 | void *tracing_cond_snapshot_data(struct trace_array *tr) |
1460 | { | |
1461 | return NULL; | |
1462 | } | |
1463 | EXPORT_SYMBOL_GPL(tracing_cond_snapshot_data); | |
1464 | int tracing_snapshot_cond_enable(struct trace_array *tr, void *cond_data, cond_update_fn_t update) | |
1465 | { | |
1466 | return -ENODEV; | |
1467 | } | |
1468 | EXPORT_SYMBOL_GPL(tracing_snapshot_cond_enable); | |
1469 | int tracing_snapshot_cond_disable(struct trace_array *tr) | |
1470 | { | |
1471 | return false; | |
1472 | } | |
1473 | EXPORT_SYMBOL_GPL(tracing_snapshot_cond_disable); | |
e25e43a4 | 1474 | #define free_snapshot(tr) do { } while (0) |
ad909e21 SRRH |
1475 | #endif /* CONFIG_TRACER_SNAPSHOT */ |
1476 | ||
2290f2c5 | 1477 | void tracer_tracing_off(struct trace_array *tr) |
10246fa3 | 1478 | { |
1c5eb448 SRV |
1479 | if (tr->array_buffer.buffer) |
1480 | ring_buffer_record_off(tr->array_buffer.buffer); | |
10246fa3 SRRH |
1481 | /* |
1482 | * This flag is looked at when buffers haven't been allocated | |
1483 | * yet, or by some tracers (like irqsoff), that just want to | |
1484 | * know if the ring buffer has been disabled, but it can handle | |
1485 | * races of where it gets disabled but we still do a record. | |
1486 | * As the check is in the fast path of the tracers, it is more | |
1487 | * important to be fast than accurate. | |
1488 | */ | |
1489 | tr->buffer_disabled = 1; | |
1490 | /* Make the flag seen by readers */ | |
1491 | smp_wmb(); | |
1492 | } | |
1493 | ||
499e5470 SR |
1494 | /** |
1495 | * tracing_off - turn off tracing buffers | |
1496 | * | |
1497 | * This function stops the tracing buffers from recording data. | |
1498 | * It does not disable any overhead the tracers themselves may | |
1499 | * be causing. This function simply causes all recording to | |
1500 | * the ring buffers to fail. | |
1501 | */ | |
1502 | void tracing_off(void) | |
1503 | { | |
10246fa3 | 1504 | tracer_tracing_off(&global_trace); |
499e5470 SR |
1505 | } |
1506 | EXPORT_SYMBOL_GPL(tracing_off); | |
1507 | ||
de7edd31 SRRH |
1508 | void disable_trace_on_warning(void) |
1509 | { | |
c200784a SRV |
1510 | if (__disable_trace_on_warning) { |
1511 | trace_array_printk_buf(global_trace.array_buffer.buffer, _THIS_IP_, | |
1512 | "Disabling tracing due to warning\n"); | |
de7edd31 | 1513 | tracing_off(); |
c200784a | 1514 | } |
de7edd31 SRRH |
1515 | } |
1516 | ||
10246fa3 SRRH |
1517 | /** |
1518 | * tracer_tracing_is_on - show real state of ring buffer enabled | |
1519 | * @tr : the trace array to know if ring buffer is enabled | |
1520 | * | |
1521 | * Shows real state of the ring buffer if it is enabled or not. | |
1522 | */ | |
ec573508 | 1523 | bool tracer_tracing_is_on(struct trace_array *tr) |
10246fa3 | 1524 | { |
1c5eb448 SRV |
1525 | if (tr->array_buffer.buffer) |
1526 | return ring_buffer_record_is_on(tr->array_buffer.buffer); | |
10246fa3 SRRH |
1527 | return !tr->buffer_disabled; |
1528 | } | |
1529 | ||
499e5470 SR |
1530 | /** |
1531 | * tracing_is_on - show state of ring buffers enabled | |
1532 | */ | |
1533 | int tracing_is_on(void) | |
1534 | { | |
10246fa3 | 1535 | return tracer_tracing_is_on(&global_trace); |
499e5470 SR |
1536 | } |
1537 | EXPORT_SYMBOL_GPL(tracing_is_on); | |
1538 | ||
3928a8a2 | 1539 | static int __init set_buf_size(char *str) |
bc0c38d1 | 1540 | { |
3928a8a2 | 1541 | unsigned long buf_size; |
c6caeeb1 | 1542 | |
bc0c38d1 SR |
1543 | if (!str) |
1544 | return 0; | |
9d612bef | 1545 | buf_size = memparse(str, &str); |
7acf3a12 SS |
1546 | /* |
1547 | * nr_entries can not be zero and the startup | |
1548 | * tests require some buffer space. Therefore | |
1549 | * ensure we have at least 4096 bytes of buffer. | |
1550 | */ | |
1551 | trace_buf_size = max(4096UL, buf_size); | |
bc0c38d1 SR |
1552 | return 1; |
1553 | } | |
3928a8a2 | 1554 | __setup("trace_buf_size=", set_buf_size); |
bc0c38d1 | 1555 | |
0e950173 TB |
1556 | static int __init set_tracing_thresh(char *str) |
1557 | { | |
87abb3b1 | 1558 | unsigned long threshold; |
0e950173 TB |
1559 | int ret; |
1560 | ||
1561 | if (!str) | |
1562 | return 0; | |
bcd83ea6 | 1563 | ret = kstrtoul(str, 0, &threshold); |
0e950173 TB |
1564 | if (ret < 0) |
1565 | return 0; | |
87abb3b1 | 1566 | tracing_thresh = threshold * 1000; |
0e950173 TB |
1567 | return 1; |
1568 | } | |
1569 | __setup("tracing_thresh=", set_tracing_thresh); | |
1570 | ||
57f50be1 SR |
1571 | unsigned long nsecs_to_usecs(unsigned long nsecs) |
1572 | { | |
1573 | return nsecs / 1000; | |
1574 | } | |
1575 | ||
a3418a36 SRRH |
1576 | /* |
1577 | * TRACE_FLAGS is defined as a tuple matching bit masks with strings. | |
f57a4143 | 1578 | * It uses C(a, b) where 'a' is the eval (enum) name and 'b' is the string that |
a3418a36 | 1579 | * matches it. By defining "C(a, b) b", TRACE_FLAGS becomes a list |
f57a4143 | 1580 | * of strings in the order that the evals (enum) were defined. |
a3418a36 SRRH |
1581 | */ |
1582 | #undef C | |
1583 | #define C(a, b) b | |
1584 | ||
f2cc020d | 1585 | /* These must match the bit positions in trace_iterator_flags */ |
bc0c38d1 | 1586 | static const char *trace_options[] = { |
a3418a36 | 1587 | TRACE_FLAGS |
bc0c38d1 SR |
1588 | NULL |
1589 | }; | |
1590 | ||
5079f326 Z |
1591 | static struct { |
1592 | u64 (*func)(void); | |
1593 | const char *name; | |
8be0709f | 1594 | int in_ns; /* is this clock in nanoseconds? */ |
5079f326 | 1595 | } trace_clocks[] = { |
1b3e5c09 TG |
1596 | { trace_clock_local, "local", 1 }, |
1597 | { trace_clock_global, "global", 1 }, | |
1598 | { trace_clock_counter, "counter", 0 }, | |
e7fda6c4 | 1599 | { trace_clock_jiffies, "uptime", 0 }, |
1b3e5c09 TG |
1600 | { trace_clock, "perf", 1 }, |
1601 | { ktime_get_mono_fast_ns, "mono", 1 }, | |
aabfa5f2 | 1602 | { ktime_get_raw_fast_ns, "mono_raw", 1 }, |
a3ed0e43 | 1603 | { ktime_get_boot_fast_ns, "boot", 1 }, |
c575afe2 | 1604 | { ktime_get_tai_fast_ns, "tai", 1 }, |
8cbd9cc6 | 1605 | ARCH_TRACE_CLOCKS |
5079f326 Z |
1606 | }; |
1607 | ||
860f9f6b TZ |
1608 | bool trace_clock_in_ns(struct trace_array *tr) |
1609 | { | |
1610 | if (trace_clocks[tr->clock_id].in_ns) | |
1611 | return true; | |
1612 | ||
1613 | return false; | |
1614 | } | |
1615 | ||
b63f39ea | 1616 | /* |
1617 | * trace_parser_get_init - gets the buffer for trace parser | |
1618 | */ | |
1619 | int trace_parser_get_init(struct trace_parser *parser, int size) | |
1620 | { | |
1621 | memset(parser, 0, sizeof(*parser)); | |
1622 | ||
1623 | parser->buffer = kmalloc(size, GFP_KERNEL); | |
1624 | if (!parser->buffer) | |
1625 | return 1; | |
1626 | ||
1627 | parser->size = size; | |
1628 | return 0; | |
1629 | } | |
1630 | ||
1631 | /* | |
1632 | * trace_parser_put - frees the buffer for trace parser | |
1633 | */ | |
1634 | void trace_parser_put(struct trace_parser *parser) | |
1635 | { | |
1636 | kfree(parser->buffer); | |
0e684b65 | 1637 | parser->buffer = NULL; |
b63f39ea | 1638 | } |
1639 | ||
1640 | /* | |
1641 | * trace_get_user - reads the user input string separated by space | |
1642 | * (matched by isspace(ch)) | |
1643 | * | |
1644 | * For each string found the 'struct trace_parser' is updated, | |
1645 | * and the function returns. | |
1646 | * | |
1647 | * Returns number of bytes read. | |
1648 | * | |
1649 | * See kernel/trace/trace.h for 'struct trace_parser' details. | |
1650 | */ | |
1651 | int trace_get_user(struct trace_parser *parser, const char __user *ubuf, | |
1652 | size_t cnt, loff_t *ppos) | |
1653 | { | |
1654 | char ch; | |
1655 | size_t read = 0; | |
1656 | ssize_t ret; | |
1657 | ||
1658 | if (!*ppos) | |
1659 | trace_parser_clear(parser); | |
1660 | ||
1661 | ret = get_user(ch, ubuf++); | |
1662 | if (ret) | |
1663 | goto out; | |
1664 | ||
1665 | read++; | |
1666 | cnt--; | |
1667 | ||
1668 | /* | |
1669 | * The parser is not finished with the last write, | |
1670 | * continue reading the user input without skipping spaces. | |
1671 | */ | |
1672 | if (!parser->cont) { | |
1673 | /* skip white space */ | |
1674 | while (cnt && isspace(ch)) { | |
1675 | ret = get_user(ch, ubuf++); | |
1676 | if (ret) | |
1677 | goto out; | |
1678 | read++; | |
1679 | cnt--; | |
1680 | } | |
1681 | ||
76638d96 CD |
1682 | parser->idx = 0; |
1683 | ||
b63f39ea | 1684 | /* only spaces were written */ |
921a7acd | 1685 | if (isspace(ch) || !ch) { |
b63f39ea | 1686 | *ppos += read; |
1687 | ret = read; | |
1688 | goto out; | |
1689 | } | |
b63f39ea | 1690 | } |
1691 | ||
1692 | /* read the non-space input */ | |
921a7acd | 1693 | while (cnt && !isspace(ch) && ch) { |
3c235a33 | 1694 | if (parser->idx < parser->size - 1) |
b63f39ea | 1695 | parser->buffer[parser->idx++] = ch; |
1696 | else { | |
1697 | ret = -EINVAL; | |
1698 | goto out; | |
1699 | } | |
1700 | ret = get_user(ch, ubuf++); | |
1701 | if (ret) | |
1702 | goto out; | |
1703 | read++; | |
1704 | cnt--; | |
1705 | } | |
1706 | ||
1707 | /* We either got finished input or we have to wait for another call. */ | |
921a7acd | 1708 | if (isspace(ch) || !ch) { |
b63f39ea | 1709 | parser->buffer[parser->idx] = 0; |
1710 | parser->cont = false; | |
057db848 | 1711 | } else if (parser->idx < parser->size - 1) { |
b63f39ea | 1712 | parser->cont = true; |
1713 | parser->buffer[parser->idx++] = ch; | |
f4d0706c CD |
1714 | /* Make sure the parsed string always terminates with '\0'. */ |
1715 | parser->buffer[parser->idx] = 0; | |
057db848 SR |
1716 | } else { |
1717 | ret = -EINVAL; | |
1718 | goto out; | |
b63f39ea | 1719 | } |
1720 | ||
1721 | *ppos += read; | |
1722 | ret = read; | |
1723 | ||
1724 | out: | |
1725 | return ret; | |
1726 | } | |
1727 | ||
3a161d99 | 1728 | /* TODO add a seq_buf_to_buffer() */ |
b8b94265 | 1729 | static ssize_t trace_seq_to_buffer(struct trace_seq *s, void *buf, size_t cnt) |
3c56819b EGM |
1730 | { |
1731 | int len; | |
3c56819b | 1732 | |
5ac48378 | 1733 | if (trace_seq_used(s) <= s->seq.readpos) |
3c56819b EGM |
1734 | return -EBUSY; |
1735 | ||
5ac48378 | 1736 | len = trace_seq_used(s) - s->seq.readpos; |
3c56819b EGM |
1737 | if (cnt > len) |
1738 | cnt = len; | |
3a161d99 | 1739 | memcpy(buf, s->buffer + s->seq.readpos, cnt); |
3c56819b | 1740 | |
3a161d99 | 1741 | s->seq.readpos += cnt; |
3c56819b EGM |
1742 | return cnt; |
1743 | } | |
1744 | ||
0e950173 | 1745 | unsigned long __read_mostly tracing_thresh; |
e25e43a4 MHG |
1746 | |
1747 | #ifdef CONFIG_TRACER_MAX_TRACE | |
91edde2e VRB |
1748 | static const struct file_operations tracing_max_lat_fops; |
1749 | ||
6880c987 | 1750 | #ifdef LATENCY_FS_NOTIFY |
91edde2e VRB |
1751 | |
1752 | static struct workqueue_struct *fsnotify_wq; | |
1753 | ||
1754 | static void latency_fsnotify_workfn(struct work_struct *work) | |
1755 | { | |
1756 | struct trace_array *tr = container_of(work, struct trace_array, | |
1757 | fsnotify_work); | |
82ace1ef | 1758 | fsnotify_inode(tr->d_max_latency->d_inode, FS_MODIFY); |
91edde2e VRB |
1759 | } |
1760 | ||
1761 | static void latency_fsnotify_workfn_irq(struct irq_work *iwork) | |
1762 | { | |
1763 | struct trace_array *tr = container_of(iwork, struct trace_array, | |
1764 | fsnotify_irqwork); | |
1765 | queue_work(fsnotify_wq, &tr->fsnotify_work); | |
1766 | } | |
1767 | ||
1768 | static void trace_create_maxlat_file(struct trace_array *tr, | |
1769 | struct dentry *d_tracer) | |
1770 | { | |
1771 | INIT_WORK(&tr->fsnotify_work, latency_fsnotify_workfn); | |
1772 | init_irq_work(&tr->fsnotify_irqwork, latency_fsnotify_workfn_irq); | |
21ccc9cd SRV |
1773 | tr->d_max_latency = trace_create_file("tracing_max_latency", |
1774 | TRACE_MODE_WRITE, | |
7d660c9b | 1775 | d_tracer, tr, |
91edde2e VRB |
1776 | &tracing_max_lat_fops); |
1777 | } | |
1778 | ||
1779 | __init static int latency_fsnotify_init(void) | |
1780 | { | |
1781 | fsnotify_wq = alloc_workqueue("tr_max_lat_wq", | |
1782 | WQ_UNBOUND | WQ_HIGHPRI, 0); | |
1783 | if (!fsnotify_wq) { | |
1784 | pr_err("Unable to allocate tr_max_lat_wq\n"); | |
1785 | return -ENOMEM; | |
1786 | } | |
1787 | return 0; | |
1788 | } | |
1789 | ||
1790 | late_initcall_sync(latency_fsnotify_init); | |
1791 | ||
1792 | void latency_fsnotify(struct trace_array *tr) | |
1793 | { | |
1794 | if (!fsnotify_wq) | |
1795 | return; | |
1796 | /* | |
1797 | * We cannot call queue_work(&tr->fsnotify_work) from here because it's | |
1798 | * possible that we are called from __schedule() or do_idle(), which | |
1799 | * could cause a deadlock. | |
1800 | */ | |
1801 | irq_work_queue(&tr->fsnotify_irqwork); | |
1802 | } | |
1803 | ||
e25e43a4 | 1804 | #else /* !LATENCY_FS_NOTIFY */ |
91edde2e VRB |
1805 | |
1806 | #define trace_create_maxlat_file(tr, d_tracer) \ | |
21ccc9cd | 1807 | trace_create_file("tracing_max_latency", TRACE_MODE_WRITE, \ |
7d660c9b | 1808 | d_tracer, tr, &tracing_max_lat_fops) |
91edde2e VRB |
1809 | |
1810 | #endif | |
0e950173 | 1811 | |
5d4a9dba SR |
1812 | /* |
1813 | * Copy the new maximum trace into the separate maximum-trace | |
1814 | * structure. (this way the maximum trace is permanently saved, | |
5a93bae2 | 1815 | * for later retrieval via /sys/kernel/tracing/tracing_max_latency) |
5d4a9dba SR |
1816 | */ |
1817 | static void | |
1818 | __update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) | |
1819 | { | |
1c5eb448 SRV |
1820 | struct array_buffer *trace_buf = &tr->array_buffer; |
1821 | struct array_buffer *max_buf = &tr->max_buffer; | |
12883efb SRRH |
1822 | struct trace_array_cpu *data = per_cpu_ptr(trace_buf->data, cpu); |
1823 | struct trace_array_cpu *max_data = per_cpu_ptr(max_buf->data, cpu); | |
5d4a9dba | 1824 | |
12883efb SRRH |
1825 | max_buf->cpu = cpu; |
1826 | max_buf->time_start = data->preempt_timestamp; | |
5d4a9dba | 1827 | |
6d9b3fa5 | 1828 | max_data->saved_latency = tr->max_latency; |
8248ac05 SR |
1829 | max_data->critical_start = data->critical_start; |
1830 | max_data->critical_end = data->critical_end; | |
5d4a9dba | 1831 | |
85f726a3 | 1832 | strncpy(max_data->comm, tsk->comm, TASK_COMM_LEN); |
8248ac05 | 1833 | max_data->pid = tsk->pid; |
f17a5194 SRRH |
1834 | /* |
1835 | * If tsk == current, then use current_uid(), as that does not use | |
1836 | * RCU. The irq tracer can be called out of RCU scope. | |
1837 | */ | |
1838 | if (tsk == current) | |
1839 | max_data->uid = current_uid(); | |
1840 | else | |
1841 | max_data->uid = task_uid(tsk); | |
1842 | ||
8248ac05 SR |
1843 | max_data->nice = tsk->static_prio - 20 - MAX_RT_PRIO; |
1844 | max_data->policy = tsk->policy; | |
1845 | max_data->rt_priority = tsk->rt_priority; | |
5d4a9dba SR |
1846 | |
1847 | /* record this tasks comm */ | |
1848 | tracing_record_cmdline(tsk); | |
91edde2e | 1849 | latency_fsnotify(tr); |
5d4a9dba SR |
1850 | } |
1851 | ||
4fcdae83 SR |
1852 | /** |
1853 | * update_max_tr - snapshot all trace buffers from global_trace to max_tr | |
1854 | * @tr: tracer | |
1855 | * @tsk: the task with the latency | |
1856 | * @cpu: The cpu that initiated the trace. | |
a35873a0 | 1857 | * @cond_data: User data associated with a conditional snapshot |
4fcdae83 SR |
1858 | * |
1859 | * Flip the buffers between the @tr and the max_tr and record information | |
1860 | * about which task was the cause of this latency. | |
1861 | */ | |
e309b41d | 1862 | void |
a35873a0 TZ |
1863 | update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu, |
1864 | void *cond_data) | |
bc0c38d1 | 1865 | { |
2b6080f2 | 1866 | if (tr->stop_count) |
b8de7bd1 SR |
1867 | return; |
1868 | ||
4c11d7ae | 1869 | WARN_ON_ONCE(!irqs_disabled()); |
34600f0e | 1870 | |
45ad21ca | 1871 | if (!tr->allocated_snapshot) { |
debdd57f | 1872 | /* Only the nop tracer should hit this when disabling */ |
2b6080f2 | 1873 | WARN_ON_ONCE(tr->current_trace != &nop_trace); |
34600f0e | 1874 | return; |
debdd57f | 1875 | } |
34600f0e | 1876 | |
0b9b12c1 | 1877 | arch_spin_lock(&tr->max_lock); |
3928a8a2 | 1878 | |
1c5eb448 SRV |
1879 | /* Inherit the recordable setting from array_buffer */ |
1880 | if (ring_buffer_record_is_set_on(tr->array_buffer.buffer)) | |
73c8d894 MH |
1881 | ring_buffer_record_on(tr->max_buffer.buffer); |
1882 | else | |
1883 | ring_buffer_record_off(tr->max_buffer.buffer); | |
1884 | ||
a35873a0 | 1885 | #ifdef CONFIG_TRACER_SNAPSHOT |
e25e43a4 MHG |
1886 | if (tr->cond_snapshot && !tr->cond_snapshot->update(tr, cond_data)) { |
1887 | arch_spin_unlock(&tr->max_lock); | |
1888 | return; | |
1889 | } | |
a35873a0 | 1890 | #endif |
1c5eb448 | 1891 | swap(tr->array_buffer.buffer, tr->max_buffer.buffer); |
3928a8a2 | 1892 | |
bc0c38d1 | 1893 | __update_max_tr(tr, tsk, cpu); |
a35873a0 | 1894 | |
0b9b12c1 | 1895 | arch_spin_unlock(&tr->max_lock); |
bc0c38d1 SR |
1896 | } |
1897 | ||
1898 | /** | |
1899 | * update_max_tr_single - only copy one trace over, and reset the rest | |
c68c9ec1 JK |
1900 | * @tr: tracer |
1901 | * @tsk: task with the latency | |
1902 | * @cpu: the cpu of the buffer to copy. | |
4fcdae83 SR |
1903 | * |
1904 | * Flip the trace of a single CPU buffer between the @tr and the max_tr. | |
bc0c38d1 | 1905 | */ |
e309b41d | 1906 | void |
bc0c38d1 SR |
1907 | update_max_tr_single(struct trace_array *tr, struct task_struct *tsk, int cpu) |
1908 | { | |
3928a8a2 | 1909 | int ret; |
bc0c38d1 | 1910 | |
2b6080f2 | 1911 | if (tr->stop_count) |
b8de7bd1 SR |
1912 | return; |
1913 | ||
4c11d7ae | 1914 | WARN_ON_ONCE(!irqs_disabled()); |
6c24499f | 1915 | if (!tr->allocated_snapshot) { |
2930e04d | 1916 | /* Only the nop tracer should hit this when disabling */ |
9e8529af | 1917 | WARN_ON_ONCE(tr->current_trace != &nop_trace); |
ef710e10 | 1918 | return; |
2930e04d | 1919 | } |
ef710e10 | 1920 | |
0b9b12c1 | 1921 | arch_spin_lock(&tr->max_lock); |
bc0c38d1 | 1922 | |
1c5eb448 | 1923 | ret = ring_buffer_swap_cpu(tr->max_buffer.buffer, tr->array_buffer.buffer, cpu); |
3928a8a2 | 1924 | |
e8165dbb SR |
1925 | if (ret == -EBUSY) { |
1926 | /* | |
1927 | * We failed to swap the buffer due to a commit taking | |
1928 | * place on this CPU. We fail to record, but we reset | |
1929 | * the max trace buffer (no one writes directly to it) | |
1930 | * and flag that it failed. | |
8a96c028 | 1931 | * Another reason is resize is in progress. |
e8165dbb | 1932 | */ |
12883efb | 1933 | trace_array_printk_buf(tr->max_buffer.buffer, _THIS_IP_, |
8a96c028 | 1934 | "Failed to swap buffers due to commit or resize in progress\n"); |
e8165dbb SR |
1935 | } |
1936 | ||
e8165dbb | 1937 | WARN_ON_ONCE(ret && ret != -EAGAIN && ret != -EBUSY); |
bc0c38d1 SR |
1938 | |
1939 | __update_max_tr(tr, tsk, cpu); | |
0b9b12c1 | 1940 | arch_spin_unlock(&tr->max_lock); |
bc0c38d1 | 1941 | } |
e25e43a4 | 1942 | |
5d4a9dba | 1943 | #endif /* CONFIG_TRACER_MAX_TRACE */ |
bc0c38d1 | 1944 | |
2c2b0a78 | 1945 | static int wait_on_pipe(struct trace_iterator *iter, int full) |
0d5c6e1c | 1946 | { |
15693458 SRRH |
1947 | /* Iterators are static, they should be filled or empty */ |
1948 | if (trace_buffer_iter(iter, iter->cpu_file)) | |
8b8b3683 | 1949 | return 0; |
0d5c6e1c | 1950 | |
1c5eb448 | 1951 | return ring_buffer_wait(iter->array_buffer->buffer, iter->cpu_file, |
e30f53aa | 1952 | full); |
0d5c6e1c SR |
1953 | } |
1954 | ||
f4e781c0 | 1955 | #ifdef CONFIG_FTRACE_STARTUP_TEST |
9afecfbb SRV |
1956 | static bool selftests_can_run; |
1957 | ||
1958 | struct trace_selftests { | |
1959 | struct list_head list; | |
1960 | struct tracer *type; | |
1961 | }; | |
1962 | ||
1963 | static LIST_HEAD(postponed_selftests); | |
1964 | ||
1965 | static int save_selftest(struct tracer *type) | |
1966 | { | |
1967 | struct trace_selftests *selftest; | |
1968 | ||
1969 | selftest = kmalloc(sizeof(*selftest), GFP_KERNEL); | |
1970 | if (!selftest) | |
1971 | return -ENOMEM; | |
1972 | ||
1973 | selftest->type = type; | |
1974 | list_add(&selftest->list, &postponed_selftests); | |
1975 | return 0; | |
1976 | } | |
1977 | ||
f4e781c0 SRRH |
1978 | static int run_tracer_selftest(struct tracer *type) |
1979 | { | |
1980 | struct trace_array *tr = &global_trace; | |
1981 | struct tracer *saved_tracer = tr->current_trace; | |
1982 | int ret; | |
0d5c6e1c | 1983 | |
f4e781c0 SRRH |
1984 | if (!type->selftest || tracing_selftest_disabled) |
1985 | return 0; | |
0d5c6e1c | 1986 | |
9afecfbb SRV |
1987 | /* |
1988 | * If a tracer registers early in boot up (before scheduling is | |
1989 | * initialized and such), then do not run its selftests yet. | |
1990 | * Instead, run it a little later in the boot process. | |
1991 | */ | |
1992 | if (!selftests_can_run) | |
1993 | return save_selftest(type); | |
1994 | ||
ee666a18 SRV |
1995 | if (!tracing_is_on()) { |
1996 | pr_warn("Selftest for tracer %s skipped due to tracing disabled\n", | |
1997 | type->name); | |
1998 | return 0; | |
1999 | } | |
2000 | ||
0d5c6e1c | 2001 | /* |
f4e781c0 SRRH |
2002 | * Run a selftest on this tracer. |
2003 | * Here we reset the trace buffer, and set the current | |
2004 | * tracer to be this tracer. The tracer can then run some | |
2005 | * internal tracing to verify that everything is in order. | |
2006 | * If we fail, we do not register this tracer. | |
0d5c6e1c | 2007 | */ |
1c5eb448 | 2008 | tracing_reset_online_cpus(&tr->array_buffer); |
0d5c6e1c | 2009 | |
f4e781c0 SRRH |
2010 | tr->current_trace = type; |
2011 | ||
2012 | #ifdef CONFIG_TRACER_MAX_TRACE | |
2013 | if (type->use_max_tr) { | |
2014 | /* If we expanded the buffers, make sure the max is expanded too */ | |
2015 | if (ring_buffer_expanded) | |
2016 | ring_buffer_resize(tr->max_buffer.buffer, trace_buf_size, | |
2017 | RING_BUFFER_ALL_CPUS); | |
2018 | tr->allocated_snapshot = true; | |
2019 | } | |
2020 | #endif | |
2021 | ||
2022 | /* the test is responsible for initializing and enabling */ | |
2023 | pr_info("Testing tracer %s: ", type->name); | |
2024 | ret = type->selftest(type, tr); | |
2025 | /* the test is responsible for resetting too */ | |
2026 | tr->current_trace = saved_tracer; | |
2027 | if (ret) { | |
2028 | printk(KERN_CONT "FAILED!\n"); | |
2029 | /* Add the warning after printing 'FAILED' */ | |
2030 | WARN_ON(1); | |
2031 | return -1; | |
2032 | } | |
2033 | /* Only reset on passing, to avoid touching corrupted buffers */ | |
1c5eb448 | 2034 | tracing_reset_online_cpus(&tr->array_buffer); |
f4e781c0 SRRH |
2035 | |
2036 | #ifdef CONFIG_TRACER_MAX_TRACE | |
2037 | if (type->use_max_tr) { | |
2038 | tr->allocated_snapshot = false; | |
0d5c6e1c | 2039 | |
f4e781c0 SRRH |
2040 | /* Shrink the max buffer again */ |
2041 | if (ring_buffer_expanded) | |
2042 | ring_buffer_resize(tr->max_buffer.buffer, 1, | |
2043 | RING_BUFFER_ALL_CPUS); | |
2044 | } | |
2045 | #endif | |
2046 | ||
2047 | printk(KERN_CONT "PASSED\n"); | |
2048 | return 0; | |
2049 | } | |
9afecfbb | 2050 | |
e8352cf5 SRG |
2051 | static int do_run_tracer_selftest(struct tracer *type) |
2052 | { | |
2053 | int ret; | |
2054 | ||
9da705d4 SRG |
2055 | /* |
2056 | * Tests can take a long time, especially if they are run one after the | |
2057 | * other, as does happen during bootup when all the tracers are | |
2058 | * registered. This could cause the soft lockup watchdog to trigger. | |
2059 | */ | |
2060 | cond_resched(); | |
2061 | ||
e8352cf5 SRG |
2062 | tracing_selftest_running = true; |
2063 | ret = run_tracer_selftest(type); | |
2064 | tracing_selftest_running = false; | |
2065 | ||
2066 | return ret; | |
2067 | } | |
2068 | ||
9afecfbb SRV |
2069 | static __init int init_trace_selftests(void) |
2070 | { | |
2071 | struct trace_selftests *p, *n; | |
2072 | struct tracer *t, **last; | |
2073 | int ret; | |
2074 | ||
2075 | selftests_can_run = true; | |
2076 | ||
2077 | mutex_lock(&trace_types_lock); | |
2078 | ||
2079 | if (list_empty(&postponed_selftests)) | |
2080 | goto out; | |
2081 | ||
2082 | pr_info("Running postponed tracer tests:\n"); | |
2083 | ||
78041c0c | 2084 | tracing_selftest_running = true; |
9afecfbb | 2085 | list_for_each_entry_safe(p, n, &postponed_selftests, list) { |
6fc2171c AR |
2086 | /* This loop can take minutes when sanitizers are enabled, so |
2087 | * lets make sure we allow RCU processing. | |
2088 | */ | |
2089 | cond_resched(); | |
9afecfbb SRV |
2090 | ret = run_tracer_selftest(p->type); |
2091 | /* If the test fails, then warn and remove from available_tracers */ | |
2092 | if (ret < 0) { | |
2093 | WARN(1, "tracer: %s failed selftest, disabling\n", | |
2094 | p->type->name); | |
2095 | last = &trace_types; | |
2096 | for (t = trace_types; t; t = t->next) { | |
2097 | if (t == p->type) { | |
2098 | *last = t->next; | |
2099 | break; | |
2100 | } | |
2101 | last = &t->next; | |
2102 | } | |
2103 | } | |
2104 | list_del(&p->list); | |
2105 | kfree(p); | |
2106 | } | |
78041c0c | 2107 | tracing_selftest_running = false; |
9afecfbb SRV |
2108 | |
2109 | out: | |
2110 | mutex_unlock(&trace_types_lock); | |
2111 | ||
2112 | return 0; | |
2113 | } | |
b9ef0326 | 2114 | core_initcall(init_trace_selftests); |
f4e781c0 SRRH |
2115 | #else |
2116 | static inline int run_tracer_selftest(struct tracer *type) | |
2117 | { | |
2118 | return 0; | |
0d5c6e1c | 2119 | } |
e8352cf5 SRG |
2120 | static inline int do_run_tracer_selftest(struct tracer *type) |
2121 | { | |
2122 | return 0; | |
2123 | } | |
f4e781c0 | 2124 | #endif /* CONFIG_FTRACE_STARTUP_TEST */ |
0d5c6e1c | 2125 | |
41d9c0be SRRH |
2126 | static void add_tracer_options(struct trace_array *tr, struct tracer *t); |
2127 | ||
a4d1e688 JW |
2128 | static void __init apply_trace_boot_options(void); |
2129 | ||
4fcdae83 SR |
2130 | /** |
2131 | * register_tracer - register a tracer with the ftrace system. | |
c68c9ec1 | 2132 | * @type: the plugin for the tracer |
4fcdae83 SR |
2133 | * |
2134 | * Register a new plugin tracer. | |
2135 | */ | |
a4d1e688 | 2136 | int __init register_tracer(struct tracer *type) |
bc0c38d1 SR |
2137 | { |
2138 | struct tracer *t; | |
bc0c38d1 SR |
2139 | int ret = 0; |
2140 | ||
2141 | if (!type->name) { | |
2142 | pr_info("Tracer must have a name\n"); | |
2143 | return -1; | |
2144 | } | |
2145 | ||
24a461d5 | 2146 | if (strlen(type->name) >= MAX_TRACER_SIZE) { |
ee6c2c1b LZ |
2147 | pr_info("Tracer has a name longer than %d\n", MAX_TRACER_SIZE); |
2148 | return -1; | |
2149 | } | |
2150 | ||
a356646a | 2151 | if (security_locked_down(LOCKDOWN_TRACEFS)) { |
ee195452 | 2152 | pr_warn("Can not register tracer %s due to lockdown\n", |
a356646a SRV |
2153 | type->name); |
2154 | return -EPERM; | |
2155 | } | |
2156 | ||
bc0c38d1 | 2157 | mutex_lock(&trace_types_lock); |
86fa2f60 | 2158 | |
bc0c38d1 SR |
2159 | for (t = trace_types; t; t = t->next) { |
2160 | if (strcmp(type->name, t->name) == 0) { | |
2161 | /* already found */ | |
ee6c2c1b | 2162 | pr_info("Tracer %s already registered\n", |
bc0c38d1 SR |
2163 | type->name); |
2164 | ret = -1; | |
2165 | goto out; | |
2166 | } | |
2167 | } | |
2168 | ||
adf9f195 FW |
2169 | if (!type->set_flag) |
2170 | type->set_flag = &dummy_set_flag; | |
d39cdd20 CH |
2171 | if (!type->flags) { |
2172 | /*allocate a dummy tracer_flags*/ | |
2173 | type->flags = kmalloc(sizeof(*type->flags), GFP_KERNEL); | |
c8ca003b CH |
2174 | if (!type->flags) { |
2175 | ret = -ENOMEM; | |
2176 | goto out; | |
2177 | } | |
d39cdd20 CH |
2178 | type->flags->val = 0; |
2179 | type->flags->opts = dummy_tracer_opt; | |
2180 | } else | |
adf9f195 FW |
2181 | if (!type->flags->opts) |
2182 | type->flags->opts = dummy_tracer_opt; | |
6eaaa5d5 | 2183 | |
d39cdd20 CH |
2184 | /* store the tracer for __set_tracer_option */ |
2185 | type->flags->trace = type; | |
2186 | ||
e8352cf5 | 2187 | ret = do_run_tracer_selftest(type); |
f4e781c0 SRRH |
2188 | if (ret < 0) |
2189 | goto out; | |
60a11774 | 2190 | |
bc0c38d1 SR |
2191 | type->next = trace_types; |
2192 | trace_types = type; | |
41d9c0be | 2193 | add_tracer_options(&global_trace, type); |
60a11774 | 2194 | |
bc0c38d1 SR |
2195 | out: |
2196 | mutex_unlock(&trace_types_lock); | |
2197 | ||
dac74940 SR |
2198 | if (ret || !default_bootup_tracer) |
2199 | goto out_unlock; | |
2200 | ||
ee6c2c1b | 2201 | if (strncmp(default_bootup_tracer, type->name, MAX_TRACER_SIZE)) |
dac74940 SR |
2202 | goto out_unlock; |
2203 | ||
2204 | printk(KERN_INFO "Starting tracer '%s'\n", type->name); | |
2205 | /* Do we want this tracer to start on bootup? */ | |
607e2ea1 | 2206 | tracing_set_tracer(&global_trace, type->name); |
dac74940 | 2207 | default_bootup_tracer = NULL; |
a4d1e688 JW |
2208 | |
2209 | apply_trace_boot_options(); | |
2210 | ||
dac74940 | 2211 | /* disable other selftests, since this will break it. */ |
60efe21e | 2212 | disable_tracing_selftest("running a tracer"); |
b2821ae6 | 2213 | |
dac74940 | 2214 | out_unlock: |
bc0c38d1 SR |
2215 | return ret; |
2216 | } | |
2217 | ||
1c5eb448 | 2218 | static void tracing_reset_cpu(struct array_buffer *buf, int cpu) |
f633903a | 2219 | { |
13292494 | 2220 | struct trace_buffer *buffer = buf->buffer; |
f633903a | 2221 | |
a5416411 HT |
2222 | if (!buffer) |
2223 | return; | |
2224 | ||
f633903a SR |
2225 | ring_buffer_record_disable(buffer); |
2226 | ||
2227 | /* Make sure all commits have finished */ | |
74401729 | 2228 | synchronize_rcu(); |
68179686 | 2229 | ring_buffer_reset_cpu(buffer, cpu); |
f633903a SR |
2230 | |
2231 | ring_buffer_record_enable(buffer); | |
2232 | } | |
2233 | ||
1c5eb448 | 2234 | void tracing_reset_online_cpus(struct array_buffer *buf) |
213cc060 | 2235 | { |
13292494 | 2236 | struct trace_buffer *buffer = buf->buffer; |
213cc060 | 2237 | |
a5416411 HT |
2238 | if (!buffer) |
2239 | return; | |
2240 | ||
621968cd SR |
2241 | ring_buffer_record_disable(buffer); |
2242 | ||
2243 | /* Make sure all commits have finished */ | |
74401729 | 2244 | synchronize_rcu(); |
621968cd | 2245 | |
9457158b | 2246 | buf->time_start = buffer_ftrace_now(buf, buf->cpu); |
213cc060 | 2247 | |
b23d7a5f | 2248 | ring_buffer_reset_online_cpus(buffer); |
621968cd SR |
2249 | |
2250 | ring_buffer_record_enable(buffer); | |
213cc060 PE |
2251 | } |
2252 | ||
09d8091c | 2253 | /* Must have trace_types_lock held */ |
e18eb878 | 2254 | void tracing_reset_all_online_cpus_unlocked(void) |
9456f0fa | 2255 | { |
873c642f SRRH |
2256 | struct trace_array *tr; |
2257 | ||
e18eb878 SRG |
2258 | lockdep_assert_held(&trace_types_lock); |
2259 | ||
873c642f | 2260 | list_for_each_entry(tr, &ftrace_trace_arrays, list) { |
065e63f9 SRV |
2261 | if (!tr->clear_trace) |
2262 | continue; | |
2263 | tr->clear_trace = false; | |
1c5eb448 | 2264 | tracing_reset_online_cpus(&tr->array_buffer); |
12883efb SRRH |
2265 | #ifdef CONFIG_TRACER_MAX_TRACE |
2266 | tracing_reset_online_cpus(&tr->max_buffer); | |
2267 | #endif | |
873c642f | 2268 | } |
9456f0fa SR |
2269 | } |
2270 | ||
e18eb878 SRG |
2271 | void tracing_reset_all_online_cpus(void) |
2272 | { | |
2273 | mutex_lock(&trace_types_lock); | |
2274 | tracing_reset_all_online_cpus_unlocked(); | |
2275 | mutex_unlock(&trace_types_lock); | |
2276 | } | |
2277 | ||
4030a6e6 PB |
2278 | /* |
2279 | * The tgid_map array maps from pid to tgid; i.e. the value stored at index i | |
2280 | * is the tgid last observed corresponding to pid=i. | |
2281 | */ | |
d914ba37 JF |
2282 | static int *tgid_map; |
2283 | ||
4030a6e6 PB |
2284 | /* The maximum valid index into tgid_map. */ |
2285 | static size_t tgid_map_max; | |
2286 | ||
939c7a4f | 2287 | #define SAVED_CMDLINES_DEFAULT 128 |
2c7eea4c | 2288 | #define NO_CMDLINE_MAP UINT_MAX |
c0a581d7 WL |
2289 | /* |
2290 | * Preemption must be disabled before acquiring trace_cmdline_lock. | |
2291 | * The various trace_arrays' max_lock must be acquired in a context | |
2292 | * where interrupt is disabled. | |
2293 | */ | |
edc35bd7 | 2294 | static arch_spinlock_t trace_cmdline_lock = __ARCH_SPIN_LOCK_UNLOCKED; |
939c7a4f YY |
2295 | struct saved_cmdlines_buffer { |
2296 | unsigned map_pid_to_cmdline[PID_MAX_DEFAULT+1]; | |
2297 | unsigned *map_cmdline_to_pid; | |
2298 | unsigned cmdline_num; | |
2299 | int cmdline_idx; | |
2300 | char *saved_cmdlines; | |
2301 | }; | |
2302 | static struct saved_cmdlines_buffer *savedcmd; | |
25b0b44a | 2303 | |
939c7a4f YY |
2304 | static inline char *get_saved_cmdlines(int idx) |
2305 | { | |
2306 | return &savedcmd->saved_cmdlines[idx * TASK_COMM_LEN]; | |
2307 | } | |
2308 | ||
2309 | static inline void set_cmdline(int idx, const char *cmdline) | |
bc0c38d1 | 2310 | { |
85f726a3 | 2311 | strncpy(get_saved_cmdlines(idx), cmdline, TASK_COMM_LEN); |
939c7a4f YY |
2312 | } |
2313 | ||
2314 | static int allocate_cmdlines_buffer(unsigned int val, | |
2315 | struct saved_cmdlines_buffer *s) | |
2316 | { | |
6da2ec56 KC |
2317 | s->map_cmdline_to_pid = kmalloc_array(val, |
2318 | sizeof(*s->map_cmdline_to_pid), | |
2319 | GFP_KERNEL); | |
939c7a4f YY |
2320 | if (!s->map_cmdline_to_pid) |
2321 | return -ENOMEM; | |
2322 | ||
6da2ec56 | 2323 | s->saved_cmdlines = kmalloc_array(TASK_COMM_LEN, val, GFP_KERNEL); |
939c7a4f YY |
2324 | if (!s->saved_cmdlines) { |
2325 | kfree(s->map_cmdline_to_pid); | |
2326 | return -ENOMEM; | |
2327 | } | |
2328 | ||
2329 | s->cmdline_idx = 0; | |
2330 | s->cmdline_num = val; | |
2331 | memset(&s->map_pid_to_cmdline, NO_CMDLINE_MAP, | |
2332 | sizeof(s->map_pid_to_cmdline)); | |
2333 | memset(s->map_cmdline_to_pid, NO_CMDLINE_MAP, | |
2334 | val * sizeof(*s->map_cmdline_to_pid)); | |
2335 | ||
2336 | return 0; | |
2337 | } | |
2338 | ||
2339 | static int trace_create_savedcmd(void) | |
2340 | { | |
2341 | int ret; | |
2342 | ||
a6af8fbf | 2343 | savedcmd = kmalloc(sizeof(*savedcmd), GFP_KERNEL); |
939c7a4f YY |
2344 | if (!savedcmd) |
2345 | return -ENOMEM; | |
2346 | ||
2347 | ret = allocate_cmdlines_buffer(SAVED_CMDLINES_DEFAULT, savedcmd); | |
2348 | if (ret < 0) { | |
2349 | kfree(savedcmd); | |
2350 | savedcmd = NULL; | |
2351 | return -ENOMEM; | |
2352 | } | |
2353 | ||
2354 | return 0; | |
bc0c38d1 SR |
2355 | } |
2356 | ||
b5130b1e CE |
2357 | int is_tracing_stopped(void) |
2358 | { | |
2b6080f2 | 2359 | return global_trace.stop_count; |
b5130b1e CE |
2360 | } |
2361 | ||
0f048701 SR |
2362 | /** |
2363 | * tracing_start - quick start of the tracer | |
2364 | * | |
2365 | * If tracing is enabled but was stopped by tracing_stop, | |
2366 | * this will start the tracer back up. | |
2367 | */ | |
2368 | void tracing_start(void) | |
2369 | { | |
13292494 | 2370 | struct trace_buffer *buffer; |
0f048701 SR |
2371 | unsigned long flags; |
2372 | ||
2373 | if (tracing_disabled) | |
2374 | return; | |
2375 | ||
2b6080f2 SR |
2376 | raw_spin_lock_irqsave(&global_trace.start_lock, flags); |
2377 | if (--global_trace.stop_count) { | |
2378 | if (global_trace.stop_count < 0) { | |
b06a8301 SR |
2379 | /* Someone screwed up their debugging */ |
2380 | WARN_ON_ONCE(1); | |
2b6080f2 | 2381 | global_trace.stop_count = 0; |
b06a8301 | 2382 | } |
0f048701 SR |
2383 | goto out; |
2384 | } | |
2385 | ||
a2f80714 | 2386 | /* Prevent the buffers from switching */ |
0b9b12c1 | 2387 | arch_spin_lock(&global_trace.max_lock); |
0f048701 | 2388 | |
1c5eb448 | 2389 | buffer = global_trace.array_buffer.buffer; |
0f048701 SR |
2390 | if (buffer) |
2391 | ring_buffer_record_enable(buffer); | |
2392 | ||
12883efb SRRH |
2393 | #ifdef CONFIG_TRACER_MAX_TRACE |
2394 | buffer = global_trace.max_buffer.buffer; | |
0f048701 SR |
2395 | if (buffer) |
2396 | ring_buffer_record_enable(buffer); | |
12883efb | 2397 | #endif |
0f048701 | 2398 | |
0b9b12c1 | 2399 | arch_spin_unlock(&global_trace.max_lock); |
a2f80714 | 2400 | |
0f048701 | 2401 | out: |
2b6080f2 SR |
2402 | raw_spin_unlock_irqrestore(&global_trace.start_lock, flags); |
2403 | } | |
2404 | ||
2405 | static void tracing_start_tr(struct trace_array *tr) | |
2406 | { | |
13292494 | 2407 | struct trace_buffer *buffer; |
2b6080f2 SR |
2408 | unsigned long flags; |
2409 | ||
2410 | if (tracing_disabled) | |
2411 | return; | |
2412 | ||
2413 | /* If global, we need to also start the max tracer */ | |
2414 | if (tr->flags & TRACE_ARRAY_FL_GLOBAL) | |
2415 | return tracing_start(); | |
2416 | ||
2417 | raw_spin_lock_irqsave(&tr->start_lock, flags); | |
2418 | ||
2419 | if (--tr->stop_count) { | |
2420 | if (tr->stop_count < 0) { | |
2421 | /* Someone screwed up their debugging */ | |
2422 | WARN_ON_ONCE(1); | |
2423 | tr->stop_count = 0; | |
2424 | } | |
2425 | goto out; | |
2426 | } | |
2427 | ||
1c5eb448 | 2428 | buffer = tr->array_buffer.buffer; |
2b6080f2 SR |
2429 | if (buffer) |
2430 | ring_buffer_record_enable(buffer); | |
2431 | ||
2432 | out: | |
2433 | raw_spin_unlock_irqrestore(&tr->start_lock, flags); | |
0f048701 SR |
2434 | } |
2435 | ||
2436 | /** | |
2437 | * tracing_stop - quick stop of the tracer | |
2438 | * | |
2439 | * Light weight way to stop tracing. Use in conjunction with | |
2440 | * tracing_start. | |
2441 | */ | |
2442 | void tracing_stop(void) | |
2443 | { | |
13292494 | 2444 | struct trace_buffer *buffer; |
0f048701 SR |
2445 | unsigned long flags; |
2446 | ||
2b6080f2 SR |
2447 | raw_spin_lock_irqsave(&global_trace.start_lock, flags); |
2448 | if (global_trace.stop_count++) | |
0f048701 SR |
2449 | goto out; |
2450 | ||
a2f80714 | 2451 | /* Prevent the buffers from switching */ |
0b9b12c1 | 2452 | arch_spin_lock(&global_trace.max_lock); |
a2f80714 | 2453 | |
1c5eb448 | 2454 | buffer = global_trace.array_buffer.buffer; |
0f048701 SR |
2455 | if (buffer) |
2456 | ring_buffer_record_disable(buffer); | |
2457 | ||
12883efb SRRH |
2458 | #ifdef CONFIG_TRACER_MAX_TRACE |
2459 | buffer = global_trace.max_buffer.buffer; | |
0f048701 SR |
2460 | if (buffer) |
2461 | ring_buffer_record_disable(buffer); | |
12883efb | 2462 | #endif |
0f048701 | 2463 | |
0b9b12c1 | 2464 | arch_spin_unlock(&global_trace.max_lock); |
a2f80714 | 2465 | |
0f048701 | 2466 | out: |
2b6080f2 SR |
2467 | raw_spin_unlock_irqrestore(&global_trace.start_lock, flags); |
2468 | } | |
2469 | ||
2470 | static void tracing_stop_tr(struct trace_array *tr) | |
2471 | { | |
13292494 | 2472 | struct trace_buffer *buffer; |
2b6080f2 SR |
2473 | unsigned long flags; |
2474 | ||
2475 | /* If global, we need to also stop the max tracer */ | |
2476 | if (tr->flags & TRACE_ARRAY_FL_GLOBAL) | |
2477 | return tracing_stop(); | |
2478 | ||
2479 | raw_spin_lock_irqsave(&tr->start_lock, flags); | |
2480 | if (tr->stop_count++) | |
2481 | goto out; | |
2482 | ||
1c5eb448 | 2483 | buffer = tr->array_buffer.buffer; |
2b6080f2 SR |
2484 | if (buffer) |
2485 | ring_buffer_record_disable(buffer); | |
2486 | ||
2487 | out: | |
2488 | raw_spin_unlock_irqrestore(&tr->start_lock, flags); | |
0f048701 SR |
2489 | } |
2490 | ||
379cfdac | 2491 | static int trace_save_cmdline(struct task_struct *tsk) |
bc0c38d1 | 2492 | { |
785e3c0a | 2493 | unsigned tpid, idx; |
bc0c38d1 | 2494 | |
eaf260ac JF |
2495 | /* treat recording of idle task as a success */ |
2496 | if (!tsk->pid) | |
2497 | return 1; | |
2498 | ||
785e3c0a | 2499 | tpid = tsk->pid & (PID_MAX_DEFAULT - 1); |
bc0c38d1 SR |
2500 | |
2501 | /* | |
2502 | * It's not the end of the world if we don't get | |
2503 | * the lock, but we also don't want to spin | |
2504 | * nor do we want to disable interrupts, | |
2505 | * so if we miss here, then better luck next time. | |
c0a581d7 WL |
2506 | * |
2507 | * This is called within the scheduler and wake up, so interrupts | |
2508 | * had better been disabled and run queue lock been held. | |
bc0c38d1 | 2509 | */ |
c0a581d7 | 2510 | lockdep_assert_preemption_disabled(); |
0199c4e6 | 2511 | if (!arch_spin_trylock(&trace_cmdline_lock)) |
379cfdac | 2512 | return 0; |
bc0c38d1 | 2513 | |
785e3c0a | 2514 | idx = savedcmd->map_pid_to_cmdline[tpid]; |
2c7eea4c | 2515 | if (idx == NO_CMDLINE_MAP) { |
939c7a4f | 2516 | idx = (savedcmd->cmdline_idx + 1) % savedcmd->cmdline_num; |
bc0c38d1 | 2517 | |
785e3c0a | 2518 | savedcmd->map_pid_to_cmdline[tpid] = idx; |
939c7a4f | 2519 | savedcmd->cmdline_idx = idx; |
bc0c38d1 SR |
2520 | } |
2521 | ||
785e3c0a | 2522 | savedcmd->map_cmdline_to_pid[idx] = tsk->pid; |
939c7a4f | 2523 | set_cmdline(idx, tsk->comm); |
bc0c38d1 | 2524 | |
0199c4e6 | 2525 | arch_spin_unlock(&trace_cmdline_lock); |
379cfdac SRRH |
2526 | |
2527 | return 1; | |
bc0c38d1 SR |
2528 | } |
2529 | ||
4c27e756 | 2530 | static void __trace_find_cmdline(int pid, char comm[]) |
bc0c38d1 | 2531 | { |
bc0c38d1 | 2532 | unsigned map; |
785e3c0a | 2533 | int tpid; |
bc0c38d1 | 2534 | |
4ca53085 SR |
2535 | if (!pid) { |
2536 | strcpy(comm, "<idle>"); | |
2537 | return; | |
2538 | } | |
bc0c38d1 | 2539 | |
74bf4076 SR |
2540 | if (WARN_ON_ONCE(pid < 0)) { |
2541 | strcpy(comm, "<XXX>"); | |
2542 | return; | |
2543 | } | |
2544 | ||
785e3c0a SRV |
2545 | tpid = pid & (PID_MAX_DEFAULT - 1); |
2546 | map = savedcmd->map_pid_to_cmdline[tpid]; | |
2547 | if (map != NO_CMDLINE_MAP) { | |
2548 | tpid = savedcmd->map_cmdline_to_pid[map]; | |
2549 | if (tpid == pid) { | |
c7dce4c5 | 2550 | strscpy(comm, get_saved_cmdlines(map), TASK_COMM_LEN); |
785e3c0a SRV |
2551 | return; |
2552 | } | |
4ca53085 | 2553 | } |
785e3c0a | 2554 | strcpy(comm, "<...>"); |
4c27e756 SRRH |
2555 | } |
2556 | ||
2557 | void trace_find_cmdline(int pid, char comm[]) | |
2558 | { | |
2559 | preempt_disable(); | |
2560 | arch_spin_lock(&trace_cmdline_lock); | |
2561 | ||
2562 | __trace_find_cmdline(pid, comm); | |
bc0c38d1 | 2563 | |
0199c4e6 | 2564 | arch_spin_unlock(&trace_cmdline_lock); |
5b6045a9 | 2565 | preempt_enable(); |
bc0c38d1 SR |
2566 | } |
2567 | ||
4030a6e6 PB |
2568 | static int *trace_find_tgid_ptr(int pid) |
2569 | { | |
2570 | /* | |
2571 | * Pairs with the smp_store_release in set_tracer_flag() to ensure that | |
2572 | * if we observe a non-NULL tgid_map then we also observe the correct | |
2573 | * tgid_map_max. | |
2574 | */ | |
2575 | int *map = smp_load_acquire(&tgid_map); | |
2576 | ||
2577 | if (unlikely(!map || pid > tgid_map_max)) | |
2578 | return NULL; | |
2579 | ||
2580 | return &map[pid]; | |
2581 | } | |
2582 | ||
d914ba37 JF |
2583 | int trace_find_tgid(int pid) |
2584 | { | |
4030a6e6 | 2585 | int *ptr = trace_find_tgid_ptr(pid); |
d914ba37 | 2586 | |
4030a6e6 | 2587 | return ptr ? *ptr : 0; |
d914ba37 JF |
2588 | } |
2589 | ||
2590 | static int trace_save_tgid(struct task_struct *tsk) | |
2591 | { | |
4030a6e6 PB |
2592 | int *ptr; |
2593 | ||
bd45d34d JF |
2594 | /* treat recording of idle task as a success */ |
2595 | if (!tsk->pid) | |
2596 | return 1; | |
2597 | ||
4030a6e6 PB |
2598 | ptr = trace_find_tgid_ptr(tsk->pid); |
2599 | if (!ptr) | |
d914ba37 JF |
2600 | return 0; |
2601 | ||
4030a6e6 | 2602 | *ptr = tsk->tgid; |
d914ba37 JF |
2603 | return 1; |
2604 | } | |
2605 | ||
2606 | static bool tracing_record_taskinfo_skip(int flags) | |
2607 | { | |
2608 | if (unlikely(!(flags & (TRACE_RECORD_CMDLINE | TRACE_RECORD_TGID)))) | |
2609 | return true; | |
d914ba37 JF |
2610 | if (!__this_cpu_read(trace_taskinfo_save)) |
2611 | return true; | |
2612 | return false; | |
2613 | } | |
2614 | ||
2615 | /** | |
2616 | * tracing_record_taskinfo - record the task info of a task | |
2617 | * | |
c68c9ec1 JK |
2618 | * @task: task to record |
2619 | * @flags: TRACE_RECORD_CMDLINE for recording comm | |
2620 | * TRACE_RECORD_TGID for recording tgid | |
d914ba37 JF |
2621 | */ |
2622 | void tracing_record_taskinfo(struct task_struct *task, int flags) | |
2623 | { | |
29b1a8ad JF |
2624 | bool done; |
2625 | ||
d914ba37 JF |
2626 | if (tracing_record_taskinfo_skip(flags)) |
2627 | return; | |
29b1a8ad JF |
2628 | |
2629 | /* | |
2630 | * Record as much task information as possible. If some fail, continue | |
2631 | * to try to record the others. | |
2632 | */ | |
2633 | done = !(flags & TRACE_RECORD_CMDLINE) || trace_save_cmdline(task); | |
2634 | done &= !(flags & TRACE_RECORD_TGID) || trace_save_tgid(task); | |
2635 | ||
2636 | /* If recording any information failed, retry again soon. */ | |
2637 | if (!done) | |
d914ba37 JF |
2638 | return; |
2639 | ||
2640 | __this_cpu_write(trace_taskinfo_save, false); | |
2641 | } | |
2642 | ||
2643 | /** | |
2644 | * tracing_record_taskinfo_sched_switch - record task info for sched_switch | |
2645 | * | |
c68c9ec1 JK |
2646 | * @prev: previous task during sched_switch |
2647 | * @next: next task during sched_switch | |
2648 | * @flags: TRACE_RECORD_CMDLINE for recording comm | |
2649 | * TRACE_RECORD_TGID for recording tgid | |
d914ba37 JF |
2650 | */ |
2651 | void tracing_record_taskinfo_sched_switch(struct task_struct *prev, | |
2652 | struct task_struct *next, int flags) | |
bc0c38d1 | 2653 | { |
29b1a8ad JF |
2654 | bool done; |
2655 | ||
d914ba37 JF |
2656 | if (tracing_record_taskinfo_skip(flags)) |
2657 | return; | |
2658 | ||
29b1a8ad JF |
2659 | /* |
2660 | * Record as much task information as possible. If some fail, continue | |
2661 | * to try to record the others. | |
2662 | */ | |
2663 | done = !(flags & TRACE_RECORD_CMDLINE) || trace_save_cmdline(prev); | |
2664 | done &= !(flags & TRACE_RECORD_CMDLINE) || trace_save_cmdline(next); | |
2665 | done &= !(flags & TRACE_RECORD_TGID) || trace_save_tgid(prev); | |
2666 | done &= !(flags & TRACE_RECORD_TGID) || trace_save_tgid(next); | |
bc0c38d1 | 2667 | |
29b1a8ad JF |
2668 | /* If recording any information failed, retry again soon. */ |
2669 | if (!done) | |
7ffbd48d SR |
2670 | return; |
2671 | ||
d914ba37 JF |
2672 | __this_cpu_write(trace_taskinfo_save, false); |
2673 | } | |
2674 | ||
2675 | /* Helpers to record a specific task information */ | |
2676 | void tracing_record_cmdline(struct task_struct *task) | |
2677 | { | |
2678 | tracing_record_taskinfo(task, TRACE_RECORD_CMDLINE); | |
2679 | } | |
2680 | ||
2681 | void tracing_record_tgid(struct task_struct *task) | |
2682 | { | |
2683 | tracing_record_taskinfo(task, TRACE_RECORD_TGID); | |
bc0c38d1 SR |
2684 | } |
2685 | ||
af0009fc SRV |
2686 | /* |
2687 | * Several functions return TRACE_TYPE_PARTIAL_LINE if the trace_seq | |
2688 | * overflowed, and TRACE_TYPE_HANDLED otherwise. This helper function | |
2689 | * simplifies those functions and keeps them in sync. | |
2690 | */ | |
2691 | enum print_line_t trace_handle_return(struct trace_seq *s) | |
2692 | { | |
2693 | return trace_seq_has_overflowed(s) ? | |
2694 | TRACE_TYPE_PARTIAL_LINE : TRACE_TYPE_HANDLED; | |
2695 | } | |
2696 | EXPORT_SYMBOL_GPL(trace_handle_return); | |
2697 | ||
54357f0c TG |
2698 | static unsigned short migration_disable_value(void) |
2699 | { | |
2700 | #if defined(CONFIG_SMP) | |
2701 | return current->migration_disabled; | |
2702 | #else | |
2703 | return 0; | |
2704 | #endif | |
2705 | } | |
2706 | ||
0c02006e | 2707 | unsigned int tracing_gen_ctx_irq_test(unsigned int irqs_status) |
bc0c38d1 | 2708 | { |
0c02006e | 2709 | unsigned int trace_flags = irqs_status; |
36590c50 | 2710 | unsigned int pc; |
bc0c38d1 | 2711 | |
36590c50 | 2712 | pc = preempt_count(); |
bc0c38d1 | 2713 | |
36590c50 SAS |
2714 | if (pc & NMI_MASK) |
2715 | trace_flags |= TRACE_FLAG_NMI; | |
2716 | if (pc & HARDIRQ_MASK) | |
2717 | trace_flags |= TRACE_FLAG_HARDIRQ; | |
fe427886 | 2718 | if (in_serving_softirq()) |
36590c50 | 2719 | trace_flags |= TRACE_FLAG_SOFTIRQ; |
289e7b0f SAS |
2720 | if (softirq_count() >> (SOFTIRQ_SHIFT + 1)) |
2721 | trace_flags |= TRACE_FLAG_BH_OFF; | |
36590c50 SAS |
2722 | |
2723 | if (tif_need_resched()) | |
2724 | trace_flags |= TRACE_FLAG_NEED_RESCHED; | |
2725 | if (test_preempt_need_resched()) | |
2726 | trace_flags |= TRACE_FLAG_PREEMPT_RESCHED; | |
54357f0c TG |
2727 | return (trace_flags << 16) | (min_t(unsigned int, pc & 0xff, 0xf)) | |
2728 | (min_t(unsigned int, migration_disable_value(), 0xf)) << 4; | |
bc0c38d1 SR |
2729 | } |
2730 | ||
e77405ad | 2731 | struct ring_buffer_event * |
13292494 | 2732 | trace_buffer_lock_reserve(struct trace_buffer *buffer, |
e77405ad SR |
2733 | int type, |
2734 | unsigned long len, | |
36590c50 | 2735 | unsigned int trace_ctx) |
51a763dd | 2736 | { |
36590c50 | 2737 | return __trace_buffer_lock_reserve(buffer, type, len, trace_ctx); |
0fc1b09f SRRH |
2738 | } |
2739 | ||
2740 | DEFINE_PER_CPU(struct ring_buffer_event *, trace_buffered_event); | |
2741 | DEFINE_PER_CPU(int, trace_buffered_event_cnt); | |
2742 | static int trace_buffered_event_ref; | |
2743 | ||
2744 | /** | |
2745 | * trace_buffered_event_enable - enable buffering events | |
2746 | * | |
2747 | * When events are being filtered, it is quicker to use a temporary | |
2748 | * buffer to write the event data into if there's a likely chance | |
2749 | * that it will not be committed. The discard of the ring buffer | |
2750 | * is not as fast as committing, and is much slower than copying | |
2751 | * a commit. | |
2752 | * | |
2753 | * When an event is to be filtered, allocate per cpu buffers to | |
2754 | * write the event data into, and if the event is filtered and discarded | |
2755 | * it is simply dropped, otherwise, the entire data is to be committed | |
2756 | * in one shot. | |
2757 | */ | |
2758 | void trace_buffered_event_enable(void) | |
2759 | { | |
2760 | struct ring_buffer_event *event; | |
2761 | struct page *page; | |
2762 | int cpu; | |
51a763dd | 2763 | |
0fc1b09f SRRH |
2764 | WARN_ON_ONCE(!mutex_is_locked(&event_mutex)); |
2765 | ||
2766 | if (trace_buffered_event_ref++) | |
2767 | return; | |
2768 | ||
2769 | for_each_tracing_cpu(cpu) { | |
2770 | page = alloc_pages_node(cpu_to_node(cpu), | |
2771 | GFP_KERNEL | __GFP_NORETRY, 0); | |
2772 | if (!page) | |
2773 | goto failed; | |
2774 | ||
2775 | event = page_address(page); | |
2776 | memset(event, 0, sizeof(*event)); | |
2777 | ||
2778 | per_cpu(trace_buffered_event, cpu) = event; | |
2779 | ||
2780 | preempt_disable(); | |
2781 | if (cpu == smp_processor_id() && | |
b427e765 | 2782 | __this_cpu_read(trace_buffered_event) != |
0fc1b09f SRRH |
2783 | per_cpu(trace_buffered_event, cpu)) |
2784 | WARN_ON_ONCE(1); | |
2785 | preempt_enable(); | |
51a763dd ACM |
2786 | } |
2787 | ||
0fc1b09f SRRH |
2788 | return; |
2789 | failed: | |
2790 | trace_buffered_event_disable(); | |
2791 | } | |
2792 | ||
2793 | static void enable_trace_buffered_event(void *data) | |
2794 | { | |
2795 | /* Probably not needed, but do it anyway */ | |
2796 | smp_rmb(); | |
2797 | this_cpu_dec(trace_buffered_event_cnt); | |
2798 | } | |
2799 | ||
2800 | static void disable_trace_buffered_event(void *data) | |
2801 | { | |
2802 | this_cpu_inc(trace_buffered_event_cnt); | |
2803 | } | |
2804 | ||
2805 | /** | |
2806 | * trace_buffered_event_disable - disable buffering events | |
2807 | * | |
2808 | * When a filter is removed, it is faster to not use the buffered | |
2809 | * events, and to commit directly into the ring buffer. Free up | |
2810 | * the temp buffers when there are no more users. This requires | |
2811 | * special synchronization with current events. | |
2812 | */ | |
2813 | void trace_buffered_event_disable(void) | |
2814 | { | |
2815 | int cpu; | |
2816 | ||
2817 | WARN_ON_ONCE(!mutex_is_locked(&event_mutex)); | |
2818 | ||
2819 | if (WARN_ON_ONCE(!trace_buffered_event_ref)) | |
2820 | return; | |
2821 | ||
2822 | if (--trace_buffered_event_ref) | |
2823 | return; | |
2824 | ||
2825 | preempt_disable(); | |
2826 | /* For each CPU, set the buffer as used. */ | |
2827 | smp_call_function_many(tracing_buffer_mask, | |
2828 | disable_trace_buffered_event, NULL, 1); | |
2829 | preempt_enable(); | |
2830 | ||
2831 | /* Wait for all current users to finish */ | |
74401729 | 2832 | synchronize_rcu(); |
0fc1b09f SRRH |
2833 | |
2834 | for_each_tracing_cpu(cpu) { | |
2835 | free_page((unsigned long)per_cpu(trace_buffered_event, cpu)); | |
2836 | per_cpu(trace_buffered_event, cpu) = NULL; | |
2837 | } | |
2838 | /* | |
2839 | * Make sure trace_buffered_event is NULL before clearing | |
2840 | * trace_buffered_event_cnt. | |
2841 | */ | |
2842 | smp_wmb(); | |
2843 | ||
2844 | preempt_disable(); | |
2845 | /* Do the work on each cpu */ | |
2846 | smp_call_function_many(tracing_buffer_mask, | |
2847 | enable_trace_buffered_event, NULL, 1); | |
2848 | preempt_enable(); | |
51a763dd | 2849 | } |
51a763dd | 2850 | |
13292494 | 2851 | static struct trace_buffer *temp_buffer; |
2c4a33ab | 2852 | |
ccb469a1 | 2853 | struct ring_buffer_event * |
13292494 | 2854 | trace_event_buffer_lock_reserve(struct trace_buffer **current_rb, |
7f1d2f82 | 2855 | struct trace_event_file *trace_file, |
ccb469a1 | 2856 | int type, unsigned long len, |
36590c50 | 2857 | unsigned int trace_ctx) |
ccb469a1 | 2858 | { |
2c4a33ab | 2859 | struct ring_buffer_event *entry; |
b94bc80d | 2860 | struct trace_array *tr = trace_file->tr; |
0fc1b09f | 2861 | int val; |
2c4a33ab | 2862 | |
b94bc80d | 2863 | *current_rb = tr->array_buffer.buffer; |
0fc1b09f | 2864 | |
b94bc80d | 2865 | if (!tr->no_filter_buffering_ref && |
6c536d76 SRV |
2866 | (trace_file->flags & (EVENT_FILE_FL_SOFT_DISABLED | EVENT_FILE_FL_FILTERED))) { |
2867 | preempt_disable_notrace(); | |
8f0901cd SRV |
2868 | /* |
2869 | * Filtering is on, so try to use the per cpu buffer first. | |
2870 | * This buffer will simulate a ring_buffer_event, | |
2871 | * where the type_len is zero and the array[0] will | |
2872 | * hold the full length. | |
2873 | * (see include/linux/ring-buffer.h for details on | |
2874 | * how the ring_buffer_event is structured). | |
2875 | * | |
2876 | * Using a temp buffer during filtering and copying it | |
2877 | * on a matched filter is quicker than writing directly | |
2878 | * into the ring buffer and then discarding it when | |
2879 | * it doesn't match. That is because the discard | |
2880 | * requires several atomic operations to get right. | |
2881 | * Copying on match and doing nothing on a failed match | |
2882 | * is still quicker than no copy on match, but having | |
2883 | * to discard out of the ring buffer on a failed match. | |
2884 | */ | |
6c536d76 SRV |
2885 | if ((entry = __this_cpu_read(trace_buffered_event))) { |
2886 | int max_len = PAGE_SIZE - struct_size(entry, array, 1); | |
faa76a6c | 2887 | |
6c536d76 | 2888 | val = this_cpu_inc_return(trace_buffered_event_cnt); |
8f0901cd | 2889 | |
6c536d76 SRV |
2890 | /* |
2891 | * Preemption is disabled, but interrupts and NMIs | |
2892 | * can still come in now. If that happens after | |
2893 | * the above increment, then it will have to go | |
2894 | * back to the old method of allocating the event | |
2895 | * on the ring buffer, and if the filter fails, it | |
2896 | * will have to call ring_buffer_discard_commit() | |
2897 | * to remove it. | |
2898 | * | |
2899 | * Need to also check the unlikely case that the | |
2900 | * length is bigger than the temp buffer size. | |
2901 | * If that happens, then the reserve is pretty much | |
2902 | * guaranteed to fail, as the ring buffer currently | |
2903 | * only allows events less than a page. But that may | |
2904 | * change in the future, so let the ring buffer reserve | |
2905 | * handle the failure in that case. | |
2906 | */ | |
2907 | if (val == 1 && likely(len <= max_len)) { | |
2908 | trace_event_setup(entry, type, trace_ctx); | |
2909 | entry->array[0] = len; | |
2910 | /* Return with preemption disabled */ | |
2911 | return entry; | |
2912 | } | |
2913 | this_cpu_dec(trace_buffered_event_cnt); | |
0fc1b09f | 2914 | } |
6c536d76 SRV |
2915 | /* __trace_buffer_lock_reserve() disables preemption */ |
2916 | preempt_enable_notrace(); | |
0fc1b09f SRRH |
2917 | } |
2918 | ||
36590c50 SAS |
2919 | entry = __trace_buffer_lock_reserve(*current_rb, type, len, |
2920 | trace_ctx); | |
2c4a33ab SRRH |
2921 | /* |
2922 | * If tracing is off, but we have triggers enabled | |
2923 | * we still need to look at the event data. Use the temp_buffer | |
906695e5 | 2924 | * to store the trace event for the trigger to use. It's recursive |
2c4a33ab SRRH |
2925 | * safe and will not be recorded anywhere. |
2926 | */ | |
5d6ad960 | 2927 | if (!entry && trace_file->flags & EVENT_FILE_FL_TRIGGER_COND) { |
2c4a33ab | 2928 | *current_rb = temp_buffer; |
36590c50 SAS |
2929 | entry = __trace_buffer_lock_reserve(*current_rb, type, len, |
2930 | trace_ctx); | |
2c4a33ab SRRH |
2931 | } |
2932 | return entry; | |
ccb469a1 SR |
2933 | } |
2934 | EXPORT_SYMBOL_GPL(trace_event_buffer_lock_reserve); | |
2935 | ||
12025abd | 2936 | static DEFINE_RAW_SPINLOCK(tracepoint_iter_lock); |
42391745 SRRH |
2937 | static DEFINE_MUTEX(tracepoint_printk_mutex); |
2938 | ||
2939 | static void output_printk(struct trace_event_buffer *fbuffer) | |
2940 | { | |
2941 | struct trace_event_call *event_call; | |
d8d0c245 | 2942 | struct trace_event_file *file; |
42391745 SRRH |
2943 | struct trace_event *event; |
2944 | unsigned long flags; | |
2945 | struct trace_iterator *iter = tracepoint_print_iter; | |
2946 | ||
2947 | /* We should never get here if iter is NULL */ | |
2948 | if (WARN_ON_ONCE(!iter)) | |
2949 | return; | |
2950 | ||
2951 | event_call = fbuffer->trace_file->event_call; | |
2952 | if (!event_call || !event_call->event.funcs || | |
2953 | !event_call->event.funcs->trace) | |
2954 | return; | |
2955 | ||
d8d0c245 MH |
2956 | file = fbuffer->trace_file; |
2957 | if (test_bit(EVENT_FILE_FL_SOFT_DISABLED_BIT, &file->flags) || | |
2958 | (unlikely(file->flags & EVENT_FILE_FL_FILTERED) && | |
2959 | !filter_match_preds(file->filter, fbuffer->entry))) | |
2960 | return; | |
2961 | ||
42391745 SRRH |
2962 | event = &fbuffer->trace_file->event_call->event; |
2963 | ||
12025abd | 2964 | raw_spin_lock_irqsave(&tracepoint_iter_lock, flags); |
42391745 SRRH |
2965 | trace_seq_init(&iter->seq); |
2966 | iter->ent = fbuffer->entry; | |
2967 | event_call->event.funcs->trace(iter, 0, event); | |
2968 | trace_seq_putc(&iter->seq, 0); | |
2969 | printk("%s", iter->seq.buffer); | |
2970 | ||
12025abd | 2971 | raw_spin_unlock_irqrestore(&tracepoint_iter_lock, flags); |
42391745 SRRH |
2972 | } |
2973 | ||
2974 | int tracepoint_printk_sysctl(struct ctl_table *table, int write, | |
32927393 | 2975 | void *buffer, size_t *lenp, |
42391745 SRRH |
2976 | loff_t *ppos) |
2977 | { | |
2978 | int save_tracepoint_printk; | |
2979 | int ret; | |
2980 | ||
2981 | mutex_lock(&tracepoint_printk_mutex); | |
2982 | save_tracepoint_printk = tracepoint_printk; | |
2983 | ||
2984 | ret = proc_dointvec(table, write, buffer, lenp, ppos); | |
2985 | ||
2986 | /* | |
2987 | * This will force exiting early, as tracepoint_printk | |
2988 | * is always zero when tracepoint_printk_iter is not allocated | |
2989 | */ | |
2990 | if (!tracepoint_print_iter) | |
2991 | tracepoint_printk = 0; | |
2992 | ||
2993 | if (save_tracepoint_printk == tracepoint_printk) | |
2994 | goto out; | |
2995 | ||
2996 | if (tracepoint_printk) | |
2997 | static_key_enable(&tracepoint_printk_key.key); | |
2998 | else | |
2999 | static_key_disable(&tracepoint_printk_key.key); | |
3000 | ||
3001 | out: | |
3002 | mutex_unlock(&tracepoint_printk_mutex); | |
3003 | ||
3004 | return ret; | |
3005 | } | |
3006 | ||
3007 | void trace_event_buffer_commit(struct trace_event_buffer *fbuffer) | |
3008 | { | |
6c34df6f PL |
3009 | enum event_trigger_type tt = ETT_NONE; |
3010 | struct trace_event_file *file = fbuffer->trace_file; | |
3011 | ||
3012 | if (__event_trigger_test_discard(file, fbuffer->buffer, fbuffer->event, | |
3013 | fbuffer->entry, &tt)) | |
3014 | goto discard; | |
3015 | ||
42391745 SRRH |
3016 | if (static_key_false(&tracepoint_printk_key.key)) |
3017 | output_printk(fbuffer); | |
3018 | ||
8ab7a2b7 TZ |
3019 | if (static_branch_unlikely(&trace_event_exports_enabled)) |
3020 | ftrace_exports(fbuffer->event, TRACE_EXPORT_EVENT); | |
6c34df6f PL |
3021 | |
3022 | trace_buffer_unlock_commit_regs(file->tr, fbuffer->buffer, | |
3023 | fbuffer->event, fbuffer->trace_ctx, fbuffer->regs); | |
3024 | ||
3025 | discard: | |
3026 | if (tt) | |
3027 | event_triggers_post_call(file, tt); | |
3028 | ||
42391745 SRRH |
3029 | } |
3030 | EXPORT_SYMBOL_GPL(trace_event_buffer_commit); | |
3031 | ||
2ee5b92a SRV |
3032 | /* |
3033 | * Skip 3: | |
3034 | * | |
3035 | * trace_buffer_unlock_commit_regs() | |
3036 | * trace_event_buffer_commit() | |
3037 | * trace_event_raw_event_xxx() | |
13cf912b | 3038 | */ |
2ee5b92a SRV |
3039 | # define STACK_SKIP 3 |
3040 | ||
b7f0c959 | 3041 | void trace_buffer_unlock_commit_regs(struct trace_array *tr, |
13292494 | 3042 | struct trace_buffer *buffer, |
0d5c6e1c | 3043 | struct ring_buffer_event *event, |
36590c50 | 3044 | unsigned int trace_ctx, |
0d5c6e1c | 3045 | struct pt_regs *regs) |
1fd8df2c | 3046 | { |
7ffbd48d | 3047 | __buffer_unlock_commit(buffer, event); |
1fd8df2c | 3048 | |
be54f69c | 3049 | /* |
2ee5b92a | 3050 | * If regs is not set, then skip the necessary functions. |
be54f69c SRRH |
3051 | * Note, we can still get here via blktrace, wakeup tracer |
3052 | * and mmiotrace, but that's ok if they lose a function or | |
2ee5b92a | 3053 | * two. They are not that meaningful. |
be54f69c | 3054 | */ |
36590c50 SAS |
3055 | ftrace_trace_stack(tr, buffer, trace_ctx, regs ? 0 : STACK_SKIP, regs); |
3056 | ftrace_trace_userstack(tr, buffer, trace_ctx); | |
1fd8df2c | 3057 | } |
1fd8df2c | 3058 | |
52ffabe3 SRRH |
3059 | /* |
3060 | * Similar to trace_buffer_unlock_commit_regs() but do not dump stack. | |
3061 | */ | |
3062 | void | |
13292494 | 3063 | trace_buffer_unlock_commit_nostack(struct trace_buffer *buffer, |
52ffabe3 SRRH |
3064 | struct ring_buffer_event *event) |
3065 | { | |
3066 | __buffer_unlock_commit(buffer, event); | |
3067 | } | |
3068 | ||
e309b41d | 3069 | void |
36590c50 SAS |
3070 | trace_function(struct trace_array *tr, unsigned long ip, unsigned long |
3071 | parent_ip, unsigned int trace_ctx) | |
bc0c38d1 | 3072 | { |
2425bcb9 | 3073 | struct trace_event_call *call = &event_function; |
13292494 | 3074 | struct trace_buffer *buffer = tr->array_buffer.buffer; |
3928a8a2 | 3075 | struct ring_buffer_event *event; |
777e208d | 3076 | struct ftrace_entry *entry; |
bc0c38d1 | 3077 | |
3e9a8aad | 3078 | event = __trace_buffer_lock_reserve(buffer, TRACE_FN, sizeof(*entry), |
36590c50 | 3079 | trace_ctx); |
3928a8a2 SR |
3080 | if (!event) |
3081 | return; | |
3082 | entry = ring_buffer_event_data(event); | |
777e208d SR |
3083 | entry->ip = ip; |
3084 | entry->parent_ip = parent_ip; | |
e1112b4d | 3085 | |
478409dd | 3086 | if (!call_filter_check_discard(call, entry, buffer, event)) { |
8438f521 TZ |
3087 | if (static_branch_unlikely(&trace_function_exports_enabled)) |
3088 | ftrace_exports(event, TRACE_EXPORT_FUNCTION); | |
7ffbd48d | 3089 | __buffer_unlock_commit(buffer, event); |
478409dd | 3090 | } |
bc0c38d1 SR |
3091 | } |
3092 | ||
c0a0d0d3 | 3093 | #ifdef CONFIG_STACKTRACE |
4a9bd3f1 | 3094 | |
2a820bf7 TG |
3095 | /* Allow 4 levels of nesting: normal, softirq, irq, NMI */ |
3096 | #define FTRACE_KSTACK_NESTING 4 | |
3097 | ||
3098 | #define FTRACE_KSTACK_ENTRIES (PAGE_SIZE / FTRACE_KSTACK_NESTING) | |
3099 | ||
4a9bd3f1 | 3100 | struct ftrace_stack { |
2a820bf7 | 3101 | unsigned long calls[FTRACE_KSTACK_ENTRIES]; |
4a9bd3f1 SR |
3102 | }; |
3103 | ||
2a820bf7 TG |
3104 | |
3105 | struct ftrace_stacks { | |
3106 | struct ftrace_stack stacks[FTRACE_KSTACK_NESTING]; | |
4a9bd3f1 SR |
3107 | }; |
3108 | ||
2a820bf7 | 3109 | static DEFINE_PER_CPU(struct ftrace_stacks, ftrace_stacks); |
4a9bd3f1 SR |
3110 | static DEFINE_PER_CPU(int, ftrace_stack_reserve); |
3111 | ||
13292494 | 3112 | static void __ftrace_trace_stack(struct trace_buffer *buffer, |
36590c50 SAS |
3113 | unsigned int trace_ctx, |
3114 | int skip, struct pt_regs *regs) | |
86387f7e | 3115 | { |
2425bcb9 | 3116 | struct trace_event_call *call = &event_kernel_stack; |
3928a8a2 | 3117 | struct ring_buffer_event *event; |
ee6dd0db | 3118 | unsigned int size, nr_entries; |
2a820bf7 | 3119 | struct ftrace_stack *fstack; |
777e208d | 3120 | struct stack_entry *entry; |
2a820bf7 | 3121 | int stackidx; |
4a9bd3f1 | 3122 | |
be54f69c | 3123 | /* |
2ee5b92a | 3124 | * Add one, for this function and the call to save_stack_trace() |
be54f69c SRRH |
3125 | * If regs is set, then these functions will not be in the way. |
3126 | */ | |
2ee5b92a | 3127 | #ifndef CONFIG_UNWINDER_ORC |
be54f69c | 3128 | if (!regs) |
ee6dd0db | 3129 | skip++; |
2ee5b92a | 3130 | #endif |
be54f69c | 3131 | |
4a9bd3f1 SR |
3132 | preempt_disable_notrace(); |
3133 | ||
2a820bf7 TG |
3134 | stackidx = __this_cpu_inc_return(ftrace_stack_reserve) - 1; |
3135 | ||
3136 | /* This should never happen. If it does, yell once and skip */ | |
906695e5 | 3137 | if (WARN_ON_ONCE(stackidx >= FTRACE_KSTACK_NESTING)) |
2a820bf7 TG |
3138 | goto out; |
3139 | ||
4a9bd3f1 | 3140 | /* |
2a820bf7 TG |
3141 | * The above __this_cpu_inc_return() is 'atomic' cpu local. An |
3142 | * interrupt will either see the value pre increment or post | |
3143 | * increment. If the interrupt happens pre increment it will have | |
3144 | * restored the counter when it returns. We just need a barrier to | |
3145 | * keep gcc from moving things around. | |
4a9bd3f1 SR |
3146 | */ |
3147 | barrier(); | |
4a9bd3f1 | 3148 | |
2a820bf7 | 3149 | fstack = this_cpu_ptr(ftrace_stacks.stacks) + stackidx; |
ee6dd0db | 3150 | size = ARRAY_SIZE(fstack->calls); |
4a9bd3f1 | 3151 | |
ee6dd0db TG |
3152 | if (regs) { |
3153 | nr_entries = stack_trace_save_regs(regs, fstack->calls, | |
3154 | size, skip); | |
3155 | } else { | |
3156 | nr_entries = stack_trace_save(fstack->calls, size, skip); | |
3157 | } | |
86387f7e | 3158 | |
3e9a8aad | 3159 | event = __trace_buffer_lock_reserve(buffer, TRACE_STACK, |
e7186af7 | 3160 | struct_size(entry, caller, nr_entries), |
9deb193a | 3161 | trace_ctx); |
3928a8a2 | 3162 | if (!event) |
4a9bd3f1 | 3163 | goto out; |
e7186af7 | 3164 | entry = ring_buffer_event_data(event); |
86387f7e | 3165 | |
ee6dd0db | 3166 | entry->size = nr_entries; |
e7186af7 SRG |
3167 | memcpy(&entry->caller, fstack->calls, |
3168 | flex_array_size(entry, caller, nr_entries)); | |
86387f7e | 3169 | |
f306cc82 | 3170 | if (!call_filter_check_discard(call, entry, buffer, event)) |
7ffbd48d | 3171 | __buffer_unlock_commit(buffer, event); |
4a9bd3f1 SR |
3172 | |
3173 | out: | |
3174 | /* Again, don't let gcc optimize things here */ | |
3175 | barrier(); | |
82146529 | 3176 | __this_cpu_dec(ftrace_stack_reserve); |
4a9bd3f1 SR |
3177 | preempt_enable_notrace(); |
3178 | ||
f0a920d5 IM |
3179 | } |
3180 | ||
2d34f489 | 3181 | static inline void ftrace_trace_stack(struct trace_array *tr, |
13292494 | 3182 | struct trace_buffer *buffer, |
36590c50 SAS |
3183 | unsigned int trace_ctx, |
3184 | int skip, struct pt_regs *regs) | |
53614991 | 3185 | { |
2d34f489 | 3186 | if (!(tr->trace_flags & TRACE_ITER_STACKTRACE)) |
53614991 SR |
3187 | return; |
3188 | ||
36590c50 | 3189 | __ftrace_trace_stack(buffer, trace_ctx, skip, regs); |
53614991 SR |
3190 | } |
3191 | ||
36590c50 SAS |
3192 | void __trace_stack(struct trace_array *tr, unsigned int trace_ctx, |
3193 | int skip) | |
38697053 | 3194 | { |
13292494 | 3195 | struct trace_buffer *buffer = tr->array_buffer.buffer; |
a33d7d94 SRV |
3196 | |
3197 | if (rcu_is_watching()) { | |
36590c50 | 3198 | __ftrace_trace_stack(buffer, trace_ctx, skip, NULL); |
a33d7d94 SRV |
3199 | return; |
3200 | } | |
3201 | ||
408b9611 PZ |
3202 | if (WARN_ON_ONCE(IS_ENABLED(CONFIG_GENERIC_ENTRY))) |
3203 | return; | |
3204 | ||
a33d7d94 | 3205 | /* |
493c1822 | 3206 | * When an NMI triggers, RCU is enabled via ct_nmi_enter(), |
a33d7d94 | 3207 | * but if the above rcu_is_watching() failed, then the NMI |
6f0e6c15 | 3208 | * triggered someplace critical, and ct_irq_enter() should |
a33d7d94 SRV |
3209 | * not be called from NMI. |
3210 | */ | |
3211 | if (unlikely(in_nmi())) | |
3212 | return; | |
3213 | ||
6f0e6c15 | 3214 | ct_irq_enter_irqson(); |
36590c50 | 3215 | __ftrace_trace_stack(buffer, trace_ctx, skip, NULL); |
6f0e6c15 | 3216 | ct_irq_exit_irqson(); |
38697053 SR |
3217 | } |
3218 | ||
03889384 SR |
3219 | /** |
3220 | * trace_dump_stack - record a stack back trace in the trace buffer | |
c142be8e | 3221 | * @skip: Number of functions to skip (helper handlers) |
03889384 | 3222 | */ |
c142be8e | 3223 | void trace_dump_stack(int skip) |
03889384 | 3224 | { |
03889384 | 3225 | if (tracing_disabled || tracing_selftest_running) |
e36c5458 | 3226 | return; |
03889384 | 3227 | |
2ee5b92a SRV |
3228 | #ifndef CONFIG_UNWINDER_ORC |
3229 | /* Skip 1 to skip this function. */ | |
3230 | skip++; | |
3231 | #endif | |
1c5eb448 | 3232 | __ftrace_trace_stack(global_trace.array_buffer.buffer, |
36590c50 | 3233 | tracing_gen_ctx(), skip, NULL); |
03889384 | 3234 | } |
da387e5c | 3235 | EXPORT_SYMBOL_GPL(trace_dump_stack); |
03889384 | 3236 | |
c438f140 | 3237 | #ifdef CONFIG_USER_STACKTRACE_SUPPORT |
91e86e56 SR |
3238 | static DEFINE_PER_CPU(int, user_stack_count); |
3239 | ||
c438f140 | 3240 | static void |
bcee5278 | 3241 | ftrace_trace_userstack(struct trace_array *tr, |
36590c50 | 3242 | struct trace_buffer *buffer, unsigned int trace_ctx) |
02b67518 | 3243 | { |
2425bcb9 | 3244 | struct trace_event_call *call = &event_user_stack; |
8d7c6a96 | 3245 | struct ring_buffer_event *event; |
02b67518 | 3246 | struct userstack_entry *entry; |
02b67518 | 3247 | |
bcee5278 | 3248 | if (!(tr->trace_flags & TRACE_ITER_USERSTACKTRACE)) |
02b67518 TE |
3249 | return; |
3250 | ||
b6345879 SR |
3251 | /* |
3252 | * NMIs can not handle page faults, even with fix ups. | |
3253 | * The save user stack can (and often does) fault. | |
3254 | */ | |
3255 | if (unlikely(in_nmi())) | |
3256 | return; | |
02b67518 | 3257 | |
91e86e56 SR |
3258 | /* |
3259 | * prevent recursion, since the user stack tracing may | |
3260 | * trigger other kernel events. | |
3261 | */ | |
3262 | preempt_disable(); | |
3263 | if (__this_cpu_read(user_stack_count)) | |
3264 | goto out; | |
3265 | ||
3266 | __this_cpu_inc(user_stack_count); | |
3267 | ||
3e9a8aad | 3268 | event = __trace_buffer_lock_reserve(buffer, TRACE_USER_STACK, |
36590c50 | 3269 | sizeof(*entry), trace_ctx); |
02b67518 | 3270 | if (!event) |
1dbd1951 | 3271 | goto out_drop_count; |
02b67518 | 3272 | entry = ring_buffer_event_data(event); |
02b67518 | 3273 | |
48659d31 | 3274 | entry->tgid = current->tgid; |
02b67518 TE |
3275 | memset(&entry->caller, 0, sizeof(entry->caller)); |
3276 | ||
ee6dd0db | 3277 | stack_trace_save_user(entry->caller, FTRACE_STACK_ENTRIES); |
f306cc82 | 3278 | if (!call_filter_check_discard(call, entry, buffer, event)) |
7ffbd48d | 3279 | __buffer_unlock_commit(buffer, event); |
91e86e56 | 3280 | |
1dbd1951 | 3281 | out_drop_count: |
91e86e56 | 3282 | __this_cpu_dec(user_stack_count); |
91e86e56 SR |
3283 | out: |
3284 | preempt_enable(); | |
02b67518 | 3285 | } |
c438f140 | 3286 | #else /* CONFIG_USER_STACKTRACE_SUPPORT */ |
bcee5278 SRV |
3287 | static void ftrace_trace_userstack(struct trace_array *tr, |
3288 | struct trace_buffer *buffer, | |
36590c50 | 3289 | unsigned int trace_ctx) |
02b67518 | 3290 | { |
02b67518 | 3291 | } |
c438f140 | 3292 | #endif /* !CONFIG_USER_STACKTRACE_SUPPORT */ |
02b67518 | 3293 | |
c0a0d0d3 FW |
3294 | #endif /* CONFIG_STACKTRACE */ |
3295 | ||
c658797f YKV |
3296 | static inline void |
3297 | func_repeats_set_delta_ts(struct func_repeats_entry *entry, | |
3298 | unsigned long long delta) | |
3299 | { | |
3300 | entry->bottom_delta_ts = delta & U32_MAX; | |
3301 | entry->top_delta_ts = (delta >> 32); | |
3302 | } | |
3303 | ||
3304 | void trace_last_func_repeats(struct trace_array *tr, | |
3305 | struct trace_func_repeats *last_info, | |
3306 | unsigned int trace_ctx) | |
3307 | { | |
3308 | struct trace_buffer *buffer = tr->array_buffer.buffer; | |
3309 | struct func_repeats_entry *entry; | |
3310 | struct ring_buffer_event *event; | |
3311 | u64 delta; | |
3312 | ||
3313 | event = __trace_buffer_lock_reserve(buffer, TRACE_FUNC_REPEATS, | |
3314 | sizeof(*entry), trace_ctx); | |
3315 | if (!event) | |
3316 | return; | |
3317 | ||
3318 | delta = ring_buffer_event_time_stamp(buffer, event) - | |
3319 | last_info->ts_last_call; | |
3320 | ||
3321 | entry = ring_buffer_event_data(event); | |
3322 | entry->ip = last_info->ip; | |
3323 | entry->parent_ip = last_info->parent_ip; | |
3324 | entry->count = last_info->count; | |
3325 | func_repeats_set_delta_ts(entry, delta); | |
3326 | ||
3327 | __buffer_unlock_commit(buffer, event); | |
3328 | } | |
3329 | ||
07d777fe SR |
3330 | /* created for use with alloc_percpu */ |
3331 | struct trace_buffer_struct { | |
e2ace001 AL |
3332 | int nesting; |
3333 | char buffer[4][TRACE_BUF_SIZE]; | |
07d777fe SR |
3334 | }; |
3335 | ||
f28439db | 3336 | static struct trace_buffer_struct __percpu *trace_percpu_buffer; |
07d777fe SR |
3337 | |
3338 | /* | |
2b5894cc | 3339 | * This allows for lockless recording. If we're nested too deeply, then |
e2ace001 | 3340 | * this returns NULL. |
07d777fe SR |
3341 | */ |
3342 | static char *get_trace_buf(void) | |
3343 | { | |
e2ace001 | 3344 | struct trace_buffer_struct *buffer = this_cpu_ptr(trace_percpu_buffer); |
07d777fe | 3345 | |
823e670f | 3346 | if (!trace_percpu_buffer || buffer->nesting >= 4) |
07d777fe SR |
3347 | return NULL; |
3348 | ||
3d9622c1 SRV |
3349 | buffer->nesting++; |
3350 | ||
3351 | /* Interrupts must see nesting incremented before we use the buffer */ | |
3352 | barrier(); | |
c1acb4ac | 3353 | return &buffer->buffer[buffer->nesting - 1][0]; |
e2ace001 AL |
3354 | } |
3355 | ||
3356 | static void put_trace_buf(void) | |
3357 | { | |
3d9622c1 SRV |
3358 | /* Don't let the decrement of nesting leak before this */ |
3359 | barrier(); | |
e2ace001 | 3360 | this_cpu_dec(trace_percpu_buffer->nesting); |
07d777fe SR |
3361 | } |
3362 | ||
3363 | static int alloc_percpu_trace_buffer(void) | |
3364 | { | |
f28439db | 3365 | struct trace_buffer_struct __percpu *buffers; |
07d777fe | 3366 | |
38ce2a9e SRV |
3367 | if (trace_percpu_buffer) |
3368 | return 0; | |
3369 | ||
07d777fe | 3370 | buffers = alloc_percpu(struct trace_buffer_struct); |
24589e3a | 3371 | if (MEM_FAIL(!buffers, "Could not allocate percpu trace_printk buffer")) |
e2ace001 | 3372 | return -ENOMEM; |
07d777fe SR |
3373 | |
3374 | trace_percpu_buffer = buffers; | |
07d777fe | 3375 | return 0; |
07d777fe SR |
3376 | } |
3377 | ||
81698831 SR |
3378 | static int buffers_allocated; |
3379 | ||
07d777fe SR |
3380 | void trace_printk_init_buffers(void) |
3381 | { | |
07d777fe SR |
3382 | if (buffers_allocated) |
3383 | return; | |
3384 | ||
3385 | if (alloc_percpu_trace_buffer()) | |
3386 | return; | |
3387 | ||
2184db46 SR |
3388 | /* trace_printk() is for debug use only. Don't use it in production. */ |
3389 | ||
a395d6a7 JP |
3390 | pr_warn("\n"); |
3391 | pr_warn("**********************************************************\n"); | |
3392 | pr_warn("** NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE **\n"); | |
3393 | pr_warn("** **\n"); | |
3394 | pr_warn("** trace_printk() being used. Allocating extra memory. **\n"); | |
3395 | pr_warn("** **\n"); | |
3396 | pr_warn("** This means that this is a DEBUG kernel and it is **\n"); | |
3397 | pr_warn("** unsafe for production use. **\n"); | |
3398 | pr_warn("** **\n"); | |
3399 | pr_warn("** If you see this message and you are not debugging **\n"); | |
3400 | pr_warn("** the kernel, report this immediately to your vendor! **\n"); | |
3401 | pr_warn("** **\n"); | |
3402 | pr_warn("** NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE **\n"); | |
3403 | pr_warn("**********************************************************\n"); | |
07d777fe | 3404 | |
b382ede6 SR |
3405 | /* Expand the buffers to set size */ |
3406 | tracing_update_buffers(); | |
3407 | ||
07d777fe | 3408 | buffers_allocated = 1; |
81698831 SR |
3409 | |
3410 | /* | |
3411 | * trace_printk_init_buffers() can be called by modules. | |
3412 | * If that happens, then we need to start cmdline recording | |
3413 | * directly here. If the global_trace.buffer is already | |
3414 | * allocated here, then this was called by module code. | |
3415 | */ | |
1c5eb448 | 3416 | if (global_trace.array_buffer.buffer) |
81698831 SR |
3417 | tracing_start_cmdline_record(); |
3418 | } | |
f45d1225 | 3419 | EXPORT_SYMBOL_GPL(trace_printk_init_buffers); |
81698831 SR |
3420 | |
3421 | void trace_printk_start_comm(void) | |
3422 | { | |
3423 | /* Start tracing comms if trace printk is set */ | |
3424 | if (!buffers_allocated) | |
3425 | return; | |
3426 | tracing_start_cmdline_record(); | |
3427 | } | |
3428 | ||
3429 | static void trace_printk_start_stop_comm(int enabled) | |
3430 | { | |
3431 | if (!buffers_allocated) | |
3432 | return; | |
3433 | ||
3434 | if (enabled) | |
3435 | tracing_start_cmdline_record(); | |
3436 | else | |
3437 | tracing_stop_cmdline_record(); | |
07d777fe SR |
3438 | } |
3439 | ||
769b0441 | 3440 | /** |
48ead020 | 3441 | * trace_vbprintk - write binary msg to tracing buffer |
c68c9ec1 JK |
3442 | * @ip: The address of the caller |
3443 | * @fmt: The string format to write to the buffer | |
3444 | * @args: Arguments for @fmt | |
769b0441 | 3445 | */ |
40ce74f1 | 3446 | int trace_vbprintk(unsigned long ip, const char *fmt, va_list args) |
769b0441 | 3447 | { |
2425bcb9 | 3448 | struct trace_event_call *call = &event_bprint; |
769b0441 | 3449 | struct ring_buffer_event *event; |
13292494 | 3450 | struct trace_buffer *buffer; |
769b0441 | 3451 | struct trace_array *tr = &global_trace; |
48ead020 | 3452 | struct bprint_entry *entry; |
36590c50 | 3453 | unsigned int trace_ctx; |
07d777fe | 3454 | char *tbuffer; |
36590c50 | 3455 | int len = 0, size; |
769b0441 FW |
3456 | |
3457 | if (unlikely(tracing_selftest_running || tracing_disabled)) | |
3458 | return 0; | |
3459 | ||
3460 | /* Don't pollute graph traces with trace_vprintk internals */ | |
3461 | pause_graph_tracing(); | |
3462 | ||
36590c50 | 3463 | trace_ctx = tracing_gen_ctx(); |
5168ae50 | 3464 | preempt_disable_notrace(); |
769b0441 | 3465 | |
07d777fe SR |
3466 | tbuffer = get_trace_buf(); |
3467 | if (!tbuffer) { | |
3468 | len = 0; | |
e2ace001 | 3469 | goto out_nobuffer; |
07d777fe | 3470 | } |
769b0441 | 3471 | |
07d777fe | 3472 | len = vbin_printf((u32 *)tbuffer, TRACE_BUF_SIZE/sizeof(int), fmt, args); |
769b0441 | 3473 | |
07d777fe | 3474 | if (len > TRACE_BUF_SIZE/sizeof(int) || len < 0) |
34423f25 | 3475 | goto out_put; |
769b0441 FW |
3476 | |
3477 | size = sizeof(*entry) + sizeof(u32) * len; | |
1c5eb448 | 3478 | buffer = tr->array_buffer.buffer; |
82d1b815 | 3479 | ring_buffer_nest_start(buffer); |
3e9a8aad | 3480 | event = __trace_buffer_lock_reserve(buffer, TRACE_BPRINT, size, |
36590c50 | 3481 | trace_ctx); |
769b0441 | 3482 | if (!event) |
07d777fe | 3483 | goto out; |
769b0441 FW |
3484 | entry = ring_buffer_event_data(event); |
3485 | entry->ip = ip; | |
769b0441 FW |
3486 | entry->fmt = fmt; |
3487 | ||
07d777fe | 3488 | memcpy(entry->buf, tbuffer, sizeof(u32) * len); |
f306cc82 | 3489 | if (!call_filter_check_discard(call, entry, buffer, event)) { |
7ffbd48d | 3490 | __buffer_unlock_commit(buffer, event); |
36590c50 | 3491 | ftrace_trace_stack(tr, buffer, trace_ctx, 6, NULL); |
d931369b | 3492 | } |
769b0441 | 3493 | |
769b0441 | 3494 | out: |
82d1b815 | 3495 | ring_buffer_nest_end(buffer); |
34423f25 | 3496 | out_put: |
e2ace001 AL |
3497 | put_trace_buf(); |
3498 | ||
3499 | out_nobuffer: | |
5168ae50 | 3500 | preempt_enable_notrace(); |
769b0441 FW |
3501 | unpause_graph_tracing(); |
3502 | ||
3503 | return len; | |
3504 | } | |
48ead020 FW |
3505 | EXPORT_SYMBOL_GPL(trace_vbprintk); |
3506 | ||
26b68dd2 | 3507 | __printf(3, 0) |
12883efb | 3508 | static int |
13292494 | 3509 | __trace_array_vprintk(struct trace_buffer *buffer, |
12883efb | 3510 | unsigned long ip, const char *fmt, va_list args) |
48ead020 | 3511 | { |
2425bcb9 | 3512 | struct trace_event_call *call = &event_print; |
48ead020 | 3513 | struct ring_buffer_event *event; |
36590c50 | 3514 | int len = 0, size; |
48ead020 | 3515 | struct print_entry *entry; |
36590c50 | 3516 | unsigned int trace_ctx; |
07d777fe | 3517 | char *tbuffer; |
48ead020 | 3518 | |
ac9d2cb1 | 3519 | if (tracing_disabled) |
48ead020 FW |
3520 | return 0; |
3521 | ||
07d777fe SR |
3522 | /* Don't pollute graph traces with trace_vprintk internals */ |
3523 | pause_graph_tracing(); | |
3524 | ||
36590c50 | 3525 | trace_ctx = tracing_gen_ctx(); |
48ead020 | 3526 | preempt_disable_notrace(); |
48ead020 | 3527 | |
07d777fe SR |
3528 | |
3529 | tbuffer = get_trace_buf(); | |
3530 | if (!tbuffer) { | |
3531 | len = 0; | |
e2ace001 | 3532 | goto out_nobuffer; |
07d777fe | 3533 | } |
48ead020 | 3534 | |
3558a5ac | 3535 | len = vscnprintf(tbuffer, TRACE_BUF_SIZE, fmt, args); |
48ead020 FW |
3536 | |
3537 | size = sizeof(*entry) + len + 1; | |
82d1b815 | 3538 | ring_buffer_nest_start(buffer); |
3e9a8aad | 3539 | event = __trace_buffer_lock_reserve(buffer, TRACE_PRINT, size, |
36590c50 | 3540 | trace_ctx); |
48ead020 | 3541 | if (!event) |
07d777fe | 3542 | goto out; |
48ead020 | 3543 | entry = ring_buffer_event_data(event); |
c13d2f7c | 3544 | entry->ip = ip; |
48ead020 | 3545 | |
3558a5ac | 3546 | memcpy(&entry->buf, tbuffer, len + 1); |
f306cc82 | 3547 | if (!call_filter_check_discard(call, entry, buffer, event)) { |
7ffbd48d | 3548 | __buffer_unlock_commit(buffer, event); |
36590c50 | 3549 | ftrace_trace_stack(&global_trace, buffer, trace_ctx, 6, NULL); |
d931369b | 3550 | } |
e2ace001 AL |
3551 | |
3552 | out: | |
82d1b815 | 3553 | ring_buffer_nest_end(buffer); |
e2ace001 AL |
3554 | put_trace_buf(); |
3555 | ||
3556 | out_nobuffer: | |
48ead020 | 3557 | preempt_enable_notrace(); |
07d777fe | 3558 | unpause_graph_tracing(); |
48ead020 FW |
3559 | |
3560 | return len; | |
3561 | } | |
659372d3 | 3562 | |
26b68dd2 | 3563 | __printf(3, 0) |
12883efb SRRH |
3564 | int trace_array_vprintk(struct trace_array *tr, |
3565 | unsigned long ip, const char *fmt, va_list args) | |
3566 | { | |
ac9d2cb1 SRG |
3567 | if (tracing_selftest_running && tr == &global_trace) |
3568 | return 0; | |
3569 | ||
1c5eb448 | 3570 | return __trace_array_vprintk(tr->array_buffer.buffer, ip, fmt, args); |
12883efb SRRH |
3571 | } |
3572 | ||
38ce2a9e SRV |
3573 | /** |
3574 | * trace_array_printk - Print a message to a specific instance | |
3575 | * @tr: The instance trace_array descriptor | |
3576 | * @ip: The instruction pointer that this is called from. | |
3577 | * @fmt: The format to print (printf format) | |
3578 | * | |
3579 | * If a subsystem sets up its own instance, they have the right to | |
3580 | * printk strings into their tracing instance buffer using this | |
3581 | * function. Note, this function will not write into the top level | |
3582 | * buffer (use trace_printk() for that), as writing into the top level | |
3583 | * buffer should only have events that can be individually disabled. | |
3584 | * trace_printk() is only used for debugging a kernel, and should not | |
f2cc020d | 3585 | * be ever incorporated in normal use. |
38ce2a9e SRV |
3586 | * |
3587 | * trace_array_printk() can be used, as it will not add noise to the | |
3588 | * top level tracing buffer. | |
3589 | * | |
3590 | * Note, trace_array_init_printk() must be called on @tr before this | |
3591 | * can be used. | |
3592 | */ | |
26b68dd2 | 3593 | __printf(3, 0) |
12883efb SRRH |
3594 | int trace_array_printk(struct trace_array *tr, |
3595 | unsigned long ip, const char *fmt, ...) | |
3596 | { | |
3597 | int ret; | |
3598 | va_list ap; | |
3599 | ||
953ae45a DI |
3600 | if (!tr) |
3601 | return -ENOENT; | |
3602 | ||
c791cc4b SRV |
3603 | /* This is only allowed for created instances */ |
3604 | if (tr == &global_trace) | |
3605 | return 0; | |
3606 | ||
3607 | if (!(tr->trace_flags & TRACE_ITER_PRINTK)) | |
3608 | return 0; | |
3609 | ||
12883efb SRRH |
3610 | va_start(ap, fmt); |
3611 | ret = trace_array_vprintk(tr, ip, fmt, ap); | |
3612 | va_end(ap); | |
3613 | return ret; | |
3614 | } | |
f45d1225 | 3615 | EXPORT_SYMBOL_GPL(trace_array_printk); |
12883efb | 3616 | |
38ce2a9e SRV |
3617 | /** |
3618 | * trace_array_init_printk - Initialize buffers for trace_array_printk() | |
3619 | * @tr: The trace array to initialize the buffers for | |
3620 | * | |
3621 | * As trace_array_printk() only writes into instances, they are OK to | |
3622 | * have in the kernel (unlike trace_printk()). This needs to be called | |
3623 | * before trace_array_printk() can be used on a trace_array. | |
3624 | */ | |
3625 | int trace_array_init_printk(struct trace_array *tr) | |
3626 | { | |
3627 | if (!tr) | |
3628 | return -ENOENT; | |
3629 | ||
3630 | /* This is only allowed for created instances */ | |
3631 | if (tr == &global_trace) | |
3632 | return -EINVAL; | |
3633 | ||
3634 | return alloc_percpu_trace_buffer(); | |
3635 | } | |
3636 | EXPORT_SYMBOL_GPL(trace_array_init_printk); | |
3637 | ||
26b68dd2 | 3638 | __printf(3, 4) |
13292494 | 3639 | int trace_array_printk_buf(struct trace_buffer *buffer, |
12883efb SRRH |
3640 | unsigned long ip, const char *fmt, ...) |
3641 | { | |
3642 | int ret; | |
3643 | va_list ap; | |
3644 | ||
983f938a | 3645 | if (!(global_trace.trace_flags & TRACE_ITER_PRINTK)) |
12883efb SRRH |
3646 | return 0; |
3647 | ||
3648 | va_start(ap, fmt); | |
3649 | ret = __trace_array_vprintk(buffer, ip, fmt, ap); | |
3650 | va_end(ap); | |
3651 | return ret; | |
3652 | } | |
3653 | ||
26b68dd2 | 3654 | __printf(2, 0) |
659372d3 SR |
3655 | int trace_vprintk(unsigned long ip, const char *fmt, va_list args) |
3656 | { | |
a813a159 | 3657 | return trace_array_vprintk(&global_trace, ip, fmt, args); |
659372d3 | 3658 | } |
769b0441 FW |
3659 | EXPORT_SYMBOL_GPL(trace_vprintk); |
3660 | ||
e2ac8ef5 | 3661 | static void trace_iterator_increment(struct trace_iterator *iter) |
5a90f577 | 3662 | { |
6d158a81 SR |
3663 | struct ring_buffer_iter *buf_iter = trace_buffer_iter(iter, iter->cpu); |
3664 | ||
5a90f577 | 3665 | iter->idx++; |
6d158a81 | 3666 | if (buf_iter) |
bc1a72af | 3667 | ring_buffer_iter_advance(buf_iter); |
5a90f577 SR |
3668 | } |
3669 | ||
e309b41d | 3670 | static struct trace_entry * |
bc21b478 SR |
3671 | peek_next_entry(struct trace_iterator *iter, int cpu, u64 *ts, |
3672 | unsigned long *lost_events) | |
dd0e545f | 3673 | { |
3928a8a2 | 3674 | struct ring_buffer_event *event; |
6d158a81 | 3675 | struct ring_buffer_iter *buf_iter = trace_buffer_iter(iter, cpu); |
dd0e545f | 3676 | |
c9b7a4a7 | 3677 | if (buf_iter) { |
d769041f | 3678 | event = ring_buffer_iter_peek(buf_iter, ts); |
c9b7a4a7 SRV |
3679 | if (lost_events) |
3680 | *lost_events = ring_buffer_iter_dropped(buf_iter) ? | |
3681 | (unsigned long)-1 : 0; | |
3682 | } else { | |
1c5eb448 | 3683 | event = ring_buffer_peek(iter->array_buffer->buffer, cpu, ts, |
bc21b478 | 3684 | lost_events); |
c9b7a4a7 | 3685 | } |
d769041f | 3686 | |
4a9bd3f1 SR |
3687 | if (event) { |
3688 | iter->ent_size = ring_buffer_event_length(event); | |
3689 | return ring_buffer_event_data(event); | |
3690 | } | |
3691 | iter->ent_size = 0; | |
3692 | return NULL; | |
dd0e545f | 3693 | } |
d769041f | 3694 | |
dd0e545f | 3695 | static struct trace_entry * |
bc21b478 SR |
3696 | __find_next_entry(struct trace_iterator *iter, int *ent_cpu, |
3697 | unsigned long *missing_events, u64 *ent_ts) | |
bc0c38d1 | 3698 | { |
13292494 | 3699 | struct trace_buffer *buffer = iter->array_buffer->buffer; |
bc0c38d1 | 3700 | struct trace_entry *ent, *next = NULL; |
aa27497c | 3701 | unsigned long lost_events = 0, next_lost = 0; |
b04cc6b1 | 3702 | int cpu_file = iter->cpu_file; |
3928a8a2 | 3703 | u64 next_ts = 0, ts; |
bc0c38d1 | 3704 | int next_cpu = -1; |
12b5da34 | 3705 | int next_size = 0; |
bc0c38d1 SR |
3706 | int cpu; |
3707 | ||
b04cc6b1 FW |
3708 | /* |
3709 | * If we are in a per_cpu trace file, don't bother by iterating over | |
3710 | * all cpu and peek directly. | |
3711 | */ | |
ae3b5093 | 3712 | if (cpu_file > RING_BUFFER_ALL_CPUS) { |
b04cc6b1 FW |
3713 | if (ring_buffer_empty_cpu(buffer, cpu_file)) |
3714 | return NULL; | |
bc21b478 | 3715 | ent = peek_next_entry(iter, cpu_file, ent_ts, missing_events); |
b04cc6b1 FW |
3716 | if (ent_cpu) |
3717 | *ent_cpu = cpu_file; | |
3718 | ||
3719 | return ent; | |
3720 | } | |
3721 | ||
ab46428c | 3722 | for_each_tracing_cpu(cpu) { |
dd0e545f | 3723 | |
3928a8a2 SR |
3724 | if (ring_buffer_empty_cpu(buffer, cpu)) |
3725 | continue; | |
dd0e545f | 3726 | |
bc21b478 | 3727 | ent = peek_next_entry(iter, cpu, &ts, &lost_events); |
dd0e545f | 3728 | |
cdd31cd2 IM |
3729 | /* |
3730 | * Pick the entry with the smallest timestamp: | |
3731 | */ | |
3928a8a2 | 3732 | if (ent && (!next || ts < next_ts)) { |
bc0c38d1 SR |
3733 | next = ent; |
3734 | next_cpu = cpu; | |
3928a8a2 | 3735 | next_ts = ts; |
bc21b478 | 3736 | next_lost = lost_events; |
12b5da34 | 3737 | next_size = iter->ent_size; |
bc0c38d1 SR |
3738 | } |
3739 | } | |
3740 | ||
12b5da34 SR |
3741 | iter->ent_size = next_size; |
3742 | ||
bc0c38d1 SR |
3743 | if (ent_cpu) |
3744 | *ent_cpu = next_cpu; | |
3745 | ||
3928a8a2 SR |
3746 | if (ent_ts) |
3747 | *ent_ts = next_ts; | |
3748 | ||
bc21b478 SR |
3749 | if (missing_events) |
3750 | *missing_events = next_lost; | |
3751 | ||
bc0c38d1 SR |
3752 | return next; |
3753 | } | |
3754 | ||
efbbdaa2 MH |
3755 | #define STATIC_FMT_BUF_SIZE 128 |
3756 | static char static_fmt_buf[STATIC_FMT_BUF_SIZE]; | |
3757 | ||
80a76994 | 3758 | char *trace_iter_expand_format(struct trace_iterator *iter) |
efbbdaa2 MH |
3759 | { |
3760 | char *tmp; | |
3761 | ||
0e1e71d3 SRV |
3762 | /* |
3763 | * iter->tr is NULL when used with tp_printk, which makes | |
3764 | * this get called where it is not safe to call krealloc(). | |
3765 | */ | |
3766 | if (!iter->tr || iter->fmt == static_fmt_buf) | |
efbbdaa2 MH |
3767 | return NULL; |
3768 | ||
3769 | tmp = krealloc(iter->fmt, iter->fmt_size + STATIC_FMT_BUF_SIZE, | |
3770 | GFP_KERNEL); | |
3771 | if (tmp) { | |
3772 | iter->fmt_size += STATIC_FMT_BUF_SIZE; | |
3773 | iter->fmt = tmp; | |
3774 | } | |
3775 | ||
3776 | return tmp; | |
3777 | } | |
3778 | ||
9a6944fe | 3779 | /* Returns true if the string is safe to dereference from an event */ |
eca344a7 SRG |
3780 | static bool trace_safe_str(struct trace_iterator *iter, const char *str, |
3781 | bool star, int len) | |
9a6944fe SRV |
3782 | { |
3783 | unsigned long addr = (unsigned long)str; | |
3784 | struct trace_event *trace_event; | |
3785 | struct trace_event_call *event; | |
3786 | ||
eca344a7 SRG |
3787 | /* Ignore strings with no length */ |
3788 | if (star && !len) | |
3789 | return true; | |
3790 | ||
9a6944fe SRV |
3791 | /* OK if part of the event data */ |
3792 | if ((addr >= (unsigned long)iter->ent) && | |
3793 | (addr < (unsigned long)iter->ent + iter->ent_size)) | |
3794 | return true; | |
3795 | ||
3796 | /* OK if part of the temp seq buffer */ | |
3797 | if ((addr >= (unsigned long)iter->tmp_seq.buffer) && | |
3798 | (addr < (unsigned long)iter->tmp_seq.buffer + PAGE_SIZE)) | |
3799 | return true; | |
3800 | ||
3801 | /* Core rodata can not be freed */ | |
3802 | if (is_kernel_rodata(addr)) | |
3803 | return true; | |
3804 | ||
3805 | if (trace_is_tracepoint_string(str)) | |
3806 | return true; | |
3807 | ||
3808 | /* | |
3809 | * Now this could be a module event, referencing core module | |
3810 | * data, which is OK. | |
3811 | */ | |
3812 | if (!iter->ent) | |
3813 | return false; | |
3814 | ||
3815 | trace_event = ftrace_find_event(iter->ent->type); | |
3816 | if (!trace_event) | |
3817 | return false; | |
3818 | ||
3819 | event = container_of(trace_event, struct trace_event_call, event); | |
1d18538e | 3820 | if ((event->flags & TRACE_EVENT_FL_DYNAMIC) || !event->module) |
9a6944fe SRV |
3821 | return false; |
3822 | ||
3823 | /* Would rather have rodata, but this will suffice */ | |
1d18538e | 3824 | if (within_module_core(addr, event->module)) |
9a6944fe SRV |
3825 | return true; |
3826 | ||
3827 | return false; | |
3828 | } | |
3829 | ||
3830 | static const char *show_buffer(struct trace_seq *s) | |
3831 | { | |
3832 | struct seq_buf *seq = &s->seq; | |
3833 | ||
3834 | seq_buf_terminate(seq); | |
3835 | ||
3836 | return seq->buffer; | |
3837 | } | |
3838 | ||
3839 | static DEFINE_STATIC_KEY_FALSE(trace_no_verify); | |
3840 | ||
3841 | static int test_can_verify_check(const char *fmt, ...) | |
3842 | { | |
3843 | char buf[16]; | |
3844 | va_list ap; | |
3845 | int ret; | |
3846 | ||
3847 | /* | |
3848 | * The verifier is dependent on vsnprintf() modifies the va_list | |
3849 | * passed to it, where it is sent as a reference. Some architectures | |
3850 | * (like x86_32) passes it by value, which means that vsnprintf() | |
3851 | * does not modify the va_list passed to it, and the verifier | |
3852 | * would then need to be able to understand all the values that | |
3853 | * vsnprintf can use. If it is passed by value, then the verifier | |
3854 | * is disabled. | |
3855 | */ | |
3856 | va_start(ap, fmt); | |
3857 | vsnprintf(buf, 16, "%d", ap); | |
3858 | ret = va_arg(ap, int); | |
3859 | va_end(ap); | |
3860 | ||
3861 | return ret; | |
3862 | } | |
3863 | ||
3864 | static void test_can_verify(void) | |
3865 | { | |
3866 | if (!test_can_verify_check("%d %d", 0, 1)) { | |
3867 | pr_info("trace event string verifier disabled\n"); | |
3868 | static_branch_inc(&trace_no_verify); | |
3869 | } | |
3870 | } | |
3871 | ||
3872 | /** | |
3873 | * trace_check_vprintf - Check dereferenced strings while writing to the seq buffer | |
3874 | * @iter: The iterator that holds the seq buffer and the event being printed | |
3875 | * @fmt: The format used to print the event | |
3876 | * @ap: The va_list holding the data to print from @fmt. | |
3877 | * | |
3878 | * This writes the data into the @iter->seq buffer using the data from | |
3879 | * @fmt and @ap. If the format has a %s, then the source of the string | |
3880 | * is examined to make sure it is safe to print, otherwise it will | |
3881 | * warn and print "[UNSAFE MEMORY]" in place of the dereferenced string | |
3882 | * pointer. | |
3883 | */ | |
3884 | void trace_check_vprintf(struct trace_iterator *iter, const char *fmt, | |
3885 | va_list ap) | |
3886 | { | |
3887 | const char *p = fmt; | |
3888 | const char *str; | |
3889 | int i, j; | |
3890 | ||
3891 | if (WARN_ON_ONCE(!fmt)) | |
3892 | return; | |
3893 | ||
3894 | if (static_branch_unlikely(&trace_no_verify)) | |
3895 | goto print; | |
3896 | ||
3897 | /* Don't bother checking when doing a ftrace_dump() */ | |
3898 | if (iter->fmt == static_fmt_buf) | |
3899 | goto print; | |
3900 | ||
3901 | while (*p) { | |
eb01f535 SRV |
3902 | bool star = false; |
3903 | int len = 0; | |
3904 | ||
9a6944fe SRV |
3905 | j = 0; |
3906 | ||
3907 | /* We only care about %s and variants */ | |
3908 | for (i = 0; p[i]; i++) { | |
3909 | if (i + 1 >= iter->fmt_size) { | |
3910 | /* | |
3911 | * If we can't expand the copy buffer, | |
3912 | * just print it. | |
3913 | */ | |
3914 | if (!trace_iter_expand_format(iter)) | |
3915 | goto print; | |
3916 | } | |
3917 | ||
3918 | if (p[i] == '\\' && p[i+1]) { | |
3919 | i++; | |
3920 | continue; | |
3921 | } | |
3922 | if (p[i] == '%') { | |
3923 | /* Need to test cases like %08.*s */ | |
3924 | for (j = 1; p[i+j]; j++) { | |
3925 | if (isdigit(p[i+j]) || | |
9a6944fe SRV |
3926 | p[i+j] == '.') |
3927 | continue; | |
eb01f535 SRV |
3928 | if (p[i+j] == '*') { |
3929 | star = true; | |
3930 | continue; | |
3931 | } | |
9a6944fe SRV |
3932 | break; |
3933 | } | |
3934 | if (p[i+j] == 's') | |
3935 | break; | |
eb01f535 | 3936 | star = false; |
9a6944fe SRV |
3937 | } |
3938 | j = 0; | |
3939 | } | |
3940 | /* If no %s found then just print normally */ | |
3941 | if (!p[i]) | |
3942 | break; | |
3943 | ||
3944 | /* Copy up to the %s, and print that */ | |
3945 | strncpy(iter->fmt, p, i); | |
3946 | iter->fmt[i] = '\0'; | |
3947 | trace_seq_vprintf(&iter->seq, iter->fmt, ap); | |
3948 | ||
2ef75e9b NY |
3949 | /* |
3950 | * If iter->seq is full, the above call no longer guarantees | |
3951 | * that ap is in sync with fmt processing, and further calls | |
3952 | * to va_arg() can return wrong positional arguments. | |
3953 | * | |
3954 | * Ensure that ap is no longer used in this case. | |
3955 | */ | |
3956 | if (iter->seq.full) { | |
3957 | p = ""; | |
3958 | break; | |
3959 | } | |
3960 | ||
eb01f535 SRV |
3961 | if (star) |
3962 | len = va_arg(ap, int); | |
3963 | ||
9a6944fe SRV |
3964 | /* The ap now points to the string data of the %s */ |
3965 | str = va_arg(ap, const char *); | |
3966 | ||
3967 | /* | |
3968 | * If you hit this warning, it is likely that the | |
3969 | * trace event in question used %s on a string that | |
3970 | * was saved at the time of the event, but may not be | |
3971 | * around when the trace is read. Use __string(), | |
3972 | * __assign_str() and __get_str() helpers in the TRACE_EVENT() | |
3973 | * instead. See samples/trace_events/trace-events-sample.h | |
3974 | * for reference. | |
3975 | */ | |
eca344a7 | 3976 | if (WARN_ONCE(!trace_safe_str(iter, str, star, len), |
9a6944fe SRV |
3977 | "fmt: '%s' current_buffer: '%s'", |
3978 | fmt, show_buffer(&iter->seq))) { | |
3979 | int ret; | |
3980 | ||
3981 | /* Try to safely read the string */ | |
eb01f535 SRV |
3982 | if (star) { |
3983 | if (len + 1 > iter->fmt_size) | |
3984 | len = iter->fmt_size - 1; | |
3985 | if (len < 0) | |
3986 | len = 0; | |
3987 | ret = copy_from_kernel_nofault(iter->fmt, str, len); | |
3988 | iter->fmt[len] = 0; | |
3989 | star = false; | |
3990 | } else { | |
3991 | ret = strncpy_from_kernel_nofault(iter->fmt, str, | |
3992 | iter->fmt_size); | |
3993 | } | |
9a6944fe SRV |
3994 | if (ret < 0) |
3995 | trace_seq_printf(&iter->seq, "(0x%px)", str); | |
3996 | else | |
3997 | trace_seq_printf(&iter->seq, "(0x%px:%s)", | |
3998 | str, iter->fmt); | |
3999 | str = "[UNSAFE-MEMORY]"; | |
4000 | strcpy(iter->fmt, "%s"); | |
4001 | } else { | |
4002 | strncpy(iter->fmt, p + i, j + 1); | |
4003 | iter->fmt[j+1] = '\0'; | |
4004 | } | |
eb01f535 SRV |
4005 | if (star) |
4006 | trace_seq_printf(&iter->seq, iter->fmt, len, str); | |
4007 | else | |
4008 | trace_seq_printf(&iter->seq, iter->fmt, str); | |
9a6944fe SRV |
4009 | |
4010 | p += i + j + 1; | |
4011 | } | |
4012 | print: | |
4013 | if (*p) | |
4014 | trace_seq_vprintf(&iter->seq, p, ap); | |
4015 | } | |
4016 | ||
efbbdaa2 MH |
4017 | const char *trace_event_format(struct trace_iterator *iter, const char *fmt) |
4018 | { | |
4019 | const char *p, *new_fmt; | |
4020 | char *q; | |
4021 | ||
4022 | if (WARN_ON_ONCE(!fmt)) | |
4023 | return fmt; | |
4024 | ||
0e1e71d3 | 4025 | if (!iter->tr || iter->tr->trace_flags & TRACE_ITER_HASH_PTR) |
a345a671 MH |
4026 | return fmt; |
4027 | ||
efbbdaa2 MH |
4028 | p = fmt; |
4029 | new_fmt = q = iter->fmt; | |
4030 | while (*p) { | |
4031 | if (unlikely(q - new_fmt + 3 > iter->fmt_size)) { | |
4032 | if (!trace_iter_expand_format(iter)) | |
4033 | return fmt; | |
4034 | ||
4035 | q += iter->fmt - new_fmt; | |
4036 | new_fmt = iter->fmt; | |
4037 | } | |
4038 | ||
4039 | *q++ = *p++; | |
4040 | ||
4041 | /* Replace %p with %px */ | |
4042 | if (p[-1] == '%') { | |
4043 | if (p[0] == '%') { | |
4044 | *q++ = *p++; | |
4045 | } else if (p[0] == 'p' && !isalnum(p[1])) { | |
4046 | *q++ = *p++; | |
4047 | *q++ = 'x'; | |
4048 | } | |
4049 | } | |
4050 | } | |
4051 | *q = '\0'; | |
4052 | ||
4053 | return new_fmt; | |
4054 | } | |
4055 | ||
8e99cf91 | 4056 | #define STATIC_TEMP_BUF_SIZE 128 |
8fa655a3 | 4057 | static char static_temp_buf[STATIC_TEMP_BUF_SIZE] __aligned(4); |
8e99cf91 | 4058 | |
dd0e545f | 4059 | /* Find the next real entry, without updating the iterator itself */ |
c4a8e8be FW |
4060 | struct trace_entry *trace_find_next_entry(struct trace_iterator *iter, |
4061 | int *ent_cpu, u64 *ent_ts) | |
bc0c38d1 | 4062 | { |
ff895103 SRV |
4063 | /* __find_next_entry will reset ent_size */ |
4064 | int ent_size = iter->ent_size; | |
4065 | struct trace_entry *entry; | |
4066 | ||
8e99cf91 SRV |
4067 | /* |
4068 | * If called from ftrace_dump(), then the iter->temp buffer | |
4069 | * will be the static_temp_buf and not created from kmalloc. | |
4070 | * If the entry size is greater than the buffer, we can | |
4071 | * not save it. Just return NULL in that case. This is only | |
4072 | * used to add markers when two consecutive events' time | |
4073 | * stamps have a large delta. See trace_print_lat_context() | |
4074 | */ | |
4075 | if (iter->temp == static_temp_buf && | |
4076 | STATIC_TEMP_BUF_SIZE < ent_size) | |
4077 | return NULL; | |
4078 | ||
ff895103 SRV |
4079 | /* |
4080 | * The __find_next_entry() may call peek_next_entry(), which may | |
4081 | * call ring_buffer_peek() that may make the contents of iter->ent | |
4082 | * undefined. Need to copy iter->ent now. | |
4083 | */ | |
4084 | if (iter->ent && iter->ent != iter->temp) { | |
8e99cf91 SRV |
4085 | if ((!iter->temp || iter->temp_size < iter->ent_size) && |
4086 | !WARN_ON_ONCE(iter->temp == static_temp_buf)) { | |
851e6f61 SRV |
4087 | void *temp; |
4088 | temp = kmalloc(iter->ent_size, GFP_KERNEL); | |
4089 | if (!temp) | |
ff895103 | 4090 | return NULL; |
851e6f61 SRV |
4091 | kfree(iter->temp); |
4092 | iter->temp = temp; | |
4093 | iter->temp_size = iter->ent_size; | |
ff895103 SRV |
4094 | } |
4095 | memcpy(iter->temp, iter->ent, iter->ent_size); | |
ff895103 SRV |
4096 | iter->ent = iter->temp; |
4097 | } | |
4098 | entry = __find_next_entry(iter, ent_cpu, NULL, ent_ts); | |
4099 | /* Put back the original ent_size */ | |
4100 | iter->ent_size = ent_size; | |
4101 | ||
4102 | return entry; | |
dd0e545f SR |
4103 | } |
4104 | ||
4105 | /* Find the next real entry, and increment the iterator to the next entry */ | |
955b61e5 | 4106 | void *trace_find_next_entry_inc(struct trace_iterator *iter) |
dd0e545f | 4107 | { |
bc21b478 SR |
4108 | iter->ent = __find_next_entry(iter, &iter->cpu, |
4109 | &iter->lost_events, &iter->ts); | |
dd0e545f | 4110 | |
3928a8a2 | 4111 | if (iter->ent) |
e2ac8ef5 | 4112 | trace_iterator_increment(iter); |
dd0e545f | 4113 | |
3928a8a2 | 4114 | return iter->ent ? iter : NULL; |
b3806b43 | 4115 | } |
bc0c38d1 | 4116 | |
e309b41d | 4117 | static void trace_consume(struct trace_iterator *iter) |
b3806b43 | 4118 | { |
1c5eb448 | 4119 | ring_buffer_consume(iter->array_buffer->buffer, iter->cpu, &iter->ts, |
bc21b478 | 4120 | &iter->lost_events); |
bc0c38d1 SR |
4121 | } |
4122 | ||
e309b41d | 4123 | static void *s_next(struct seq_file *m, void *v, loff_t *pos) |
bc0c38d1 SR |
4124 | { |
4125 | struct trace_iterator *iter = m->private; | |
bc0c38d1 | 4126 | int i = (int)*pos; |
4e3c3333 | 4127 | void *ent; |
bc0c38d1 | 4128 | |
a63ce5b3 SR |
4129 | WARN_ON_ONCE(iter->leftover); |
4130 | ||
bc0c38d1 SR |
4131 | (*pos)++; |
4132 | ||
4133 | /* can't go backwards */ | |
4134 | if (iter->idx > i) | |
4135 | return NULL; | |
4136 | ||
4137 | if (iter->idx < 0) | |
955b61e5 | 4138 | ent = trace_find_next_entry_inc(iter); |
bc0c38d1 SR |
4139 | else |
4140 | ent = iter; | |
4141 | ||
4142 | while (ent && iter->idx < i) | |
955b61e5 | 4143 | ent = trace_find_next_entry_inc(iter); |
bc0c38d1 SR |
4144 | |
4145 | iter->pos = *pos; | |
4146 | ||
bc0c38d1 SR |
4147 | return ent; |
4148 | } | |
4149 | ||
955b61e5 | 4150 | void tracing_iter_reset(struct trace_iterator *iter, int cpu) |
2f26ebd5 | 4151 | { |
2f26ebd5 SR |
4152 | struct ring_buffer_iter *buf_iter; |
4153 | unsigned long entries = 0; | |
4154 | u64 ts; | |
4155 | ||
1c5eb448 | 4156 | per_cpu_ptr(iter->array_buffer->data, cpu)->skipped_entries = 0; |
2f26ebd5 | 4157 | |
6d158a81 SR |
4158 | buf_iter = trace_buffer_iter(iter, cpu); |
4159 | if (!buf_iter) | |
2f26ebd5 SR |
4160 | return; |
4161 | ||
2f26ebd5 SR |
4162 | ring_buffer_iter_reset(buf_iter); |
4163 | ||
4164 | /* | |
4165 | * We could have the case with the max latency tracers | |
4166 | * that a reset never took place on a cpu. This is evident | |
4167 | * by the timestamp being before the start of the buffer. | |
4168 | */ | |
69243720 | 4169 | while (ring_buffer_iter_peek(buf_iter, &ts)) { |
1c5eb448 | 4170 | if (ts >= iter->array_buffer->time_start) |
2f26ebd5 SR |
4171 | break; |
4172 | entries++; | |
bc1a72af | 4173 | ring_buffer_iter_advance(buf_iter); |
2f26ebd5 SR |
4174 | } |
4175 | ||
1c5eb448 | 4176 | per_cpu_ptr(iter->array_buffer->data, cpu)->skipped_entries = entries; |
2f26ebd5 SR |
4177 | } |
4178 | ||
d7350c3f | 4179 | /* |
d7350c3f FW |
4180 | * The current tracer is copied to avoid a global locking |
4181 | * all around. | |
4182 | */ | |
bc0c38d1 SR |
4183 | static void *s_start(struct seq_file *m, loff_t *pos) |
4184 | { | |
4185 | struct trace_iterator *iter = m->private; | |
2b6080f2 | 4186 | struct trace_array *tr = iter->tr; |
b04cc6b1 | 4187 | int cpu_file = iter->cpu_file; |
bc0c38d1 SR |
4188 | void *p = NULL; |
4189 | loff_t l = 0; | |
3928a8a2 | 4190 | int cpu; |
bc0c38d1 SR |
4191 | |
4192 | mutex_lock(&trace_types_lock); | |
34232fcf | 4193 | if (unlikely(tr->current_trace != iter->trace)) { |
eecb91b9 ZY |
4194 | /* Close iter->trace before switching to the new current tracer */ |
4195 | if (iter->trace->close) | |
4196 | iter->trace->close(iter); | |
9182b519 | 4197 | iter->trace = tr->current_trace; |
eecb91b9 ZY |
4198 | /* Reopen the new current tracer */ |
4199 | if (iter->trace->open) | |
4200 | iter->trace->open(iter); | |
4201 | } | |
d7350c3f | 4202 | mutex_unlock(&trace_types_lock); |
bc0c38d1 | 4203 | |
12883efb | 4204 | #ifdef CONFIG_TRACER_MAX_TRACE |
debdd57f HT |
4205 | if (iter->snapshot && iter->trace->use_max_tr) |
4206 | return ERR_PTR(-EBUSY); | |
12883efb | 4207 | #endif |
debdd57f | 4208 | |
bc0c38d1 SR |
4209 | if (*pos != iter->pos) { |
4210 | iter->ent = NULL; | |
4211 | iter->cpu = 0; | |
4212 | iter->idx = -1; | |
4213 | ||
ae3b5093 | 4214 | if (cpu_file == RING_BUFFER_ALL_CPUS) { |
b04cc6b1 | 4215 | for_each_tracing_cpu(cpu) |
2f26ebd5 | 4216 | tracing_iter_reset(iter, cpu); |
b04cc6b1 | 4217 | } else |
2f26ebd5 | 4218 | tracing_iter_reset(iter, cpu_file); |
bc0c38d1 | 4219 | |
ac91d854 | 4220 | iter->leftover = 0; |
bc0c38d1 SR |
4221 | for (p = iter; p && l < *pos; p = s_next(m, p, &l)) |
4222 | ; | |
4223 | ||
4224 | } else { | |
a63ce5b3 SR |
4225 | /* |
4226 | * If we overflowed the seq_file before, then we want | |
4227 | * to just reuse the trace_seq buffer again. | |
4228 | */ | |
4229 | if (iter->leftover) | |
4230 | p = iter; | |
4231 | else { | |
4232 | l = *pos - 1; | |
4233 | p = s_next(m, p, &l); | |
4234 | } | |
bc0c38d1 SR |
4235 | } |
4236 | ||
4f535968 | 4237 | trace_event_read_lock(); |
7e53bd42 | 4238 | trace_access_lock(cpu_file); |
bc0c38d1 SR |
4239 | return p; |
4240 | } | |
4241 | ||
4242 | static void s_stop(struct seq_file *m, void *p) | |
4243 | { | |
7e53bd42 LJ |
4244 | struct trace_iterator *iter = m->private; |
4245 | ||
12883efb | 4246 | #ifdef CONFIG_TRACER_MAX_TRACE |
debdd57f HT |
4247 | if (iter->snapshot && iter->trace->use_max_tr) |
4248 | return; | |
12883efb | 4249 | #endif |
debdd57f | 4250 | |
7e53bd42 | 4251 | trace_access_unlock(iter->cpu_file); |
4f535968 | 4252 | trace_event_read_unlock(); |
bc0c38d1 SR |
4253 | } |
4254 | ||
ecffc8a8 | 4255 | static void |
1c5eb448 | 4256 | get_total_entries_cpu(struct array_buffer *buf, unsigned long *total, |
ecffc8a8 DA |
4257 | unsigned long *entries, int cpu) |
4258 | { | |
4259 | unsigned long count; | |
4260 | ||
4261 | count = ring_buffer_entries_cpu(buf->buffer, cpu); | |
4262 | /* | |
4263 | * If this buffer has skipped entries, then we hold all | |
4264 | * entries for the trace and we need to ignore the | |
4265 | * ones before the time stamp. | |
4266 | */ | |
4267 | if (per_cpu_ptr(buf->data, cpu)->skipped_entries) { | |
4268 | count -= per_cpu_ptr(buf->data, cpu)->skipped_entries; | |
4269 | /* total is the same as the entries */ | |
4270 | *total = count; | |
4271 | } else | |
4272 | *total = count + | |
4273 | ring_buffer_overrun_cpu(buf->buffer, cpu); | |
4274 | *entries = count; | |
4275 | } | |
4276 | ||
39eaf7ef | 4277 | static void |
1c5eb448 | 4278 | get_total_entries(struct array_buffer *buf, |
12883efb | 4279 | unsigned long *total, unsigned long *entries) |
39eaf7ef | 4280 | { |
ecffc8a8 | 4281 | unsigned long t, e; |
39eaf7ef SR |
4282 | int cpu; |
4283 | ||
4284 | *total = 0; | |
4285 | *entries = 0; | |
4286 | ||
4287 | for_each_tracing_cpu(cpu) { | |
ecffc8a8 DA |
4288 | get_total_entries_cpu(buf, &t, &e, cpu); |
4289 | *total += t; | |
4290 | *entries += e; | |
39eaf7ef SR |
4291 | } |
4292 | } | |
4293 | ||
ecffc8a8 DA |
4294 | unsigned long trace_total_entries_cpu(struct trace_array *tr, int cpu) |
4295 | { | |
4296 | unsigned long total, entries; | |
4297 | ||
4298 | if (!tr) | |
4299 | tr = &global_trace; | |
4300 | ||
1c5eb448 | 4301 | get_total_entries_cpu(&tr->array_buffer, &total, &entries, cpu); |
ecffc8a8 DA |
4302 | |
4303 | return entries; | |
4304 | } | |
4305 | ||
4306 | unsigned long trace_total_entries(struct trace_array *tr) | |
4307 | { | |
4308 | unsigned long total, entries; | |
4309 | ||
4310 | if (!tr) | |
4311 | tr = &global_trace; | |
4312 | ||
1c5eb448 | 4313 | get_total_entries(&tr->array_buffer, &total, &entries); |
ecffc8a8 DA |
4314 | |
4315 | return entries; | |
4316 | } | |
4317 | ||
e309b41d | 4318 | static void print_lat_help_header(struct seq_file *m) |
bc0c38d1 | 4319 | { |
795d6379 | 4320 | seq_puts(m, "# _------=> CPU# \n" |
289e7b0f | 4321 | "# / _-----=> irqs-off/BH-disabled\n" |
795d6379 SAS |
4322 | "# | / _----=> need-resched \n" |
4323 | "# || / _---=> hardirq/softirq \n" | |
4324 | "# ||| / _--=> preempt-depth \n" | |
54357f0c TG |
4325 | "# |||| / _-=> migrate-disable \n" |
4326 | "# ||||| / delay \n" | |
4327 | "# cmd pid |||||| time | caller \n" | |
4328 | "# \\ / |||||| \\ | / \n"); | |
bc0c38d1 SR |
4329 | } |
4330 | ||
1c5eb448 | 4331 | static void print_event_info(struct array_buffer *buf, struct seq_file *m) |
bc0c38d1 | 4332 | { |
39eaf7ef SR |
4333 | unsigned long total; |
4334 | unsigned long entries; | |
4335 | ||
12883efb | 4336 | get_total_entries(buf, &total, &entries); |
39eaf7ef SR |
4337 | seq_printf(m, "# entries-in-buffer/entries-written: %lu/%lu #P:%d\n", |
4338 | entries, total, num_online_cpus()); | |
4339 | seq_puts(m, "#\n"); | |
4340 | } | |
4341 | ||
1c5eb448 | 4342 | static void print_func_help_header(struct array_buffer *buf, struct seq_file *m, |
441dae8f | 4343 | unsigned int flags) |
39eaf7ef | 4344 | { |
441dae8f JF |
4345 | bool tgid = flags & TRACE_ITER_RECORD_TGID; |
4346 | ||
12883efb | 4347 | print_event_info(buf, m); |
441dae8f | 4348 | |
795d6379 SAS |
4349 | seq_printf(m, "# TASK-PID %s CPU# TIMESTAMP FUNCTION\n", tgid ? " TGID " : ""); |
4350 | seq_printf(m, "# | | %s | | |\n", tgid ? " | " : ""); | |
bc0c38d1 SR |
4351 | } |
4352 | ||
1c5eb448 | 4353 | static void print_func_help_header_irq(struct array_buffer *buf, struct seq_file *m, |
441dae8f | 4354 | unsigned int flags) |
77271ce4 | 4355 | { |
441dae8f | 4356 | bool tgid = flags & TRACE_ITER_RECORD_TGID; |
2d601b98 | 4357 | static const char space[] = " "; |
795d6379 | 4358 | int prec = tgid ? 12 : 2; |
b11fb737 | 4359 | |
9e738215 QP |
4360 | print_event_info(buf, m); |
4361 | ||
289e7b0f | 4362 | seq_printf(m, "# %.*s _-----=> irqs-off/BH-disabled\n", prec, space); |
795d6379 SAS |
4363 | seq_printf(m, "# %.*s / _----=> need-resched\n", prec, space); |
4364 | seq_printf(m, "# %.*s| / _---=> hardirq/softirq\n", prec, space); | |
4365 | seq_printf(m, "# %.*s|| / _--=> preempt-depth\n", prec, space); | |
54357f0c TG |
4366 | seq_printf(m, "# %.*s||| / _-=> migrate-disable\n", prec, space); |
4367 | seq_printf(m, "# %.*s|||| / delay\n", prec, space); | |
4368 | seq_printf(m, "# TASK-PID %.*s CPU# ||||| TIMESTAMP FUNCTION\n", prec, " TGID "); | |
4369 | seq_printf(m, "# | | %.*s | ||||| | |\n", prec, " | "); | |
77271ce4 | 4370 | } |
bc0c38d1 | 4371 | |
62b915f1 | 4372 | void |
bc0c38d1 SR |
4373 | print_trace_header(struct seq_file *m, struct trace_iterator *iter) |
4374 | { | |
983f938a | 4375 | unsigned long sym_flags = (global_trace.trace_flags & TRACE_ITER_SYM_MASK); |
1c5eb448 | 4376 | struct array_buffer *buf = iter->array_buffer; |
12883efb | 4377 | struct trace_array_cpu *data = per_cpu_ptr(buf->data, buf->cpu); |
2b6080f2 | 4378 | struct tracer *type = iter->trace; |
39eaf7ef SR |
4379 | unsigned long entries; |
4380 | unsigned long total; | |
2decd16f | 4381 | const char *name = type->name; |
bc0c38d1 | 4382 | |
12883efb | 4383 | get_total_entries(buf, &total, &entries); |
bc0c38d1 | 4384 | |
888b55dc | 4385 | seq_printf(m, "# %s latency trace v1.1.5 on %s\n", |
bc0c38d1 | 4386 | name, UTS_RELEASE); |
888b55dc | 4387 | seq_puts(m, "# -----------------------------------" |
bc0c38d1 | 4388 | "---------------------------------\n"); |
888b55dc | 4389 | seq_printf(m, "# latency: %lu us, #%lu/%lu, CPU#%d |" |
bc0c38d1 | 4390 | " (M:%s VP:%d, KP:%d, SP:%d HP:%d", |
57f50be1 | 4391 | nsecs_to_usecs(data->saved_latency), |
bc0c38d1 | 4392 | entries, |
4c11d7ae | 4393 | total, |
12883efb | 4394 | buf->cpu, |
089c02ae VS |
4395 | preempt_model_none() ? "server" : |
4396 | preempt_model_voluntary() ? "desktop" : | |
4397 | preempt_model_full() ? "preempt" : | |
4398 | preempt_model_rt() ? "preempt_rt" : | |
bc0c38d1 | 4399 | "unknown", |
bc0c38d1 SR |
4400 | /* These are reserved for later use */ |
4401 | 0, 0, 0, 0); | |
4402 | #ifdef CONFIG_SMP | |
4403 | seq_printf(m, " #P:%d)\n", num_online_cpus()); | |
4404 | #else | |
4405 | seq_puts(m, ")\n"); | |
4406 | #endif | |
888b55dc KM |
4407 | seq_puts(m, "# -----------------\n"); |
4408 | seq_printf(m, "# | task: %.16s-%d " | |
bc0c38d1 | 4409 | "(uid:%d nice:%ld policy:%ld rt_prio:%ld)\n", |
d20b92ab EB |
4410 | data->comm, data->pid, |
4411 | from_kuid_munged(seq_user_ns(m), data->uid), data->nice, | |
bc0c38d1 | 4412 | data->policy, data->rt_priority); |
888b55dc | 4413 | seq_puts(m, "# -----------------\n"); |
bc0c38d1 SR |
4414 | |
4415 | if (data->critical_start) { | |
888b55dc | 4416 | seq_puts(m, "# => started at: "); |
214023c3 SR |
4417 | seq_print_ip_sym(&iter->seq, data->critical_start, sym_flags); |
4418 | trace_print_seq(m, &iter->seq); | |
888b55dc | 4419 | seq_puts(m, "\n# => ended at: "); |
214023c3 SR |
4420 | seq_print_ip_sym(&iter->seq, data->critical_end, sym_flags); |
4421 | trace_print_seq(m, &iter->seq); | |
8248ac05 | 4422 | seq_puts(m, "\n#\n"); |
bc0c38d1 SR |
4423 | } |
4424 | ||
888b55dc | 4425 | seq_puts(m, "#\n"); |
bc0c38d1 SR |
4426 | } |
4427 | ||
a309720c SR |
4428 | static void test_cpu_buff_start(struct trace_iterator *iter) |
4429 | { | |
4430 | struct trace_seq *s = &iter->seq; | |
983f938a | 4431 | struct trace_array *tr = iter->tr; |
a309720c | 4432 | |
983f938a | 4433 | if (!(tr->trace_flags & TRACE_ITER_ANNOTATE)) |
12ef7d44 SR |
4434 | return; |
4435 | ||
4436 | if (!(iter->iter_flags & TRACE_FILE_ANNOTATE)) | |
4437 | return; | |
4438 | ||
4dbbe2d8 MK |
4439 | if (cpumask_available(iter->started) && |
4440 | cpumask_test_cpu(iter->cpu, iter->started)) | |
a309720c SR |
4441 | return; |
4442 | ||
1c5eb448 | 4443 | if (per_cpu_ptr(iter->array_buffer->data, iter->cpu)->skipped_entries) |
2f26ebd5 SR |
4444 | return; |
4445 | ||
4dbbe2d8 | 4446 | if (cpumask_available(iter->started)) |
919cd979 | 4447 | cpumask_set_cpu(iter->cpu, iter->started); |
b0dfa978 FW |
4448 | |
4449 | /* Don't print started cpu buffer for the first entry of the trace */ | |
4450 | if (iter->idx > 1) | |
4451 | trace_seq_printf(s, "##### CPU %u buffer started ####\n", | |
4452 | iter->cpu); | |
a309720c SR |
4453 | } |
4454 | ||
2c4f035f | 4455 | static enum print_line_t print_trace_fmt(struct trace_iterator *iter) |
bc0c38d1 | 4456 | { |
983f938a | 4457 | struct trace_array *tr = iter->tr; |
214023c3 | 4458 | struct trace_seq *s = &iter->seq; |
983f938a | 4459 | unsigned long sym_flags = (tr->trace_flags & TRACE_ITER_SYM_MASK); |
4e3c3333 | 4460 | struct trace_entry *entry; |
f633cef0 | 4461 | struct trace_event *event; |
bc0c38d1 | 4462 | |
4e3c3333 | 4463 | entry = iter->ent; |
dd0e545f | 4464 | |
a309720c SR |
4465 | test_cpu_buff_start(iter); |
4466 | ||
c4a8e8be | 4467 | event = ftrace_find_event(entry->type); |
bc0c38d1 | 4468 | |
983f938a | 4469 | if (tr->trace_flags & TRACE_ITER_CONTEXT_INFO) { |
19a7fe20 SRRH |
4470 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) |
4471 | trace_print_lat_context(iter); | |
4472 | else | |
4473 | trace_print_context(iter); | |
c4a8e8be | 4474 | } |
bc0c38d1 | 4475 | |
19a7fe20 SRRH |
4476 | if (trace_seq_has_overflowed(s)) |
4477 | return TRACE_TYPE_PARTIAL_LINE; | |
4478 | ||
80a76994 SRG |
4479 | if (event) { |
4480 | if (tr->trace_flags & TRACE_ITER_FIELDS) | |
4481 | return print_event_fields(iter, event); | |
a9a57763 | 4482 | return event->funcs->trace(iter, sym_flags, event); |
80a76994 | 4483 | } |
d9793bd8 | 4484 | |
19a7fe20 | 4485 | trace_seq_printf(s, "Unknown type %d\n", entry->type); |
02b67518 | 4486 | |
19a7fe20 | 4487 | return trace_handle_return(s); |
bc0c38d1 SR |
4488 | } |
4489 | ||
2c4f035f | 4490 | static enum print_line_t print_raw_fmt(struct trace_iterator *iter) |
f9896bf3 | 4491 | { |
983f938a | 4492 | struct trace_array *tr = iter->tr; |
f9896bf3 IM |
4493 | struct trace_seq *s = &iter->seq; |
4494 | struct trace_entry *entry; | |
f633cef0 | 4495 | struct trace_event *event; |
f9896bf3 IM |
4496 | |
4497 | entry = iter->ent; | |
dd0e545f | 4498 | |
983f938a | 4499 | if (tr->trace_flags & TRACE_ITER_CONTEXT_INFO) |
19a7fe20 SRRH |
4500 | trace_seq_printf(s, "%d %d %llu ", |
4501 | entry->pid, iter->cpu, iter->ts); | |
4502 | ||
4503 | if (trace_seq_has_overflowed(s)) | |
4504 | return TRACE_TYPE_PARTIAL_LINE; | |
f9896bf3 | 4505 | |
f633cef0 | 4506 | event = ftrace_find_event(entry->type); |
268ccda0 | 4507 | if (event) |
a9a57763 | 4508 | return event->funcs->raw(iter, 0, event); |
d9793bd8 | 4509 | |
19a7fe20 | 4510 | trace_seq_printf(s, "%d ?\n", entry->type); |
777e208d | 4511 | |
19a7fe20 | 4512 | return trace_handle_return(s); |
f9896bf3 IM |
4513 | } |
4514 | ||
2c4f035f | 4515 | static enum print_line_t print_hex_fmt(struct trace_iterator *iter) |
5e3ca0ec | 4516 | { |
983f938a | 4517 | struct trace_array *tr = iter->tr; |
5e3ca0ec IM |
4518 | struct trace_seq *s = &iter->seq; |
4519 | unsigned char newline = '\n'; | |
4520 | struct trace_entry *entry; | |
f633cef0 | 4521 | struct trace_event *event; |
5e3ca0ec IM |
4522 | |
4523 | entry = iter->ent; | |
dd0e545f | 4524 | |
983f938a | 4525 | if (tr->trace_flags & TRACE_ITER_CONTEXT_INFO) { |
19a7fe20 SRRH |
4526 | SEQ_PUT_HEX_FIELD(s, entry->pid); |
4527 | SEQ_PUT_HEX_FIELD(s, iter->cpu); | |
4528 | SEQ_PUT_HEX_FIELD(s, iter->ts); | |
4529 | if (trace_seq_has_overflowed(s)) | |
4530 | return TRACE_TYPE_PARTIAL_LINE; | |
c4a8e8be | 4531 | } |
5e3ca0ec | 4532 | |
f633cef0 | 4533 | event = ftrace_find_event(entry->type); |
268ccda0 | 4534 | if (event) { |
a9a57763 | 4535 | enum print_line_t ret = event->funcs->hex(iter, 0, event); |
d9793bd8 ACM |
4536 | if (ret != TRACE_TYPE_HANDLED) |
4537 | return ret; | |
4538 | } | |
7104f300 | 4539 | |
19a7fe20 | 4540 | SEQ_PUT_FIELD(s, newline); |
5e3ca0ec | 4541 | |
19a7fe20 | 4542 | return trace_handle_return(s); |
5e3ca0ec IM |
4543 | } |
4544 | ||
2c4f035f | 4545 | static enum print_line_t print_bin_fmt(struct trace_iterator *iter) |
cb0f12aa | 4546 | { |
983f938a | 4547 | struct trace_array *tr = iter->tr; |
cb0f12aa IM |
4548 | struct trace_seq *s = &iter->seq; |
4549 | struct trace_entry *entry; | |
f633cef0 | 4550 | struct trace_event *event; |
cb0f12aa IM |
4551 | |
4552 | entry = iter->ent; | |
dd0e545f | 4553 | |
983f938a | 4554 | if (tr->trace_flags & TRACE_ITER_CONTEXT_INFO) { |
19a7fe20 SRRH |
4555 | SEQ_PUT_FIELD(s, entry->pid); |
4556 | SEQ_PUT_FIELD(s, iter->cpu); | |
4557 | SEQ_PUT_FIELD(s, iter->ts); | |
4558 | if (trace_seq_has_overflowed(s)) | |
4559 | return TRACE_TYPE_PARTIAL_LINE; | |
c4a8e8be | 4560 | } |
cb0f12aa | 4561 | |
f633cef0 | 4562 | event = ftrace_find_event(entry->type); |
a9a57763 SR |
4563 | return event ? event->funcs->binary(iter, 0, event) : |
4564 | TRACE_TYPE_HANDLED; | |
cb0f12aa IM |
4565 | } |
4566 | ||
62b915f1 | 4567 | int trace_empty(struct trace_iterator *iter) |
bc0c38d1 | 4568 | { |
6d158a81 | 4569 | struct ring_buffer_iter *buf_iter; |
bc0c38d1 SR |
4570 | int cpu; |
4571 | ||
9aba60fe | 4572 | /* If we are looking at one CPU buffer, only check that one */ |
ae3b5093 | 4573 | if (iter->cpu_file != RING_BUFFER_ALL_CPUS) { |
9aba60fe | 4574 | cpu = iter->cpu_file; |
6d158a81 SR |
4575 | buf_iter = trace_buffer_iter(iter, cpu); |
4576 | if (buf_iter) { | |
4577 | if (!ring_buffer_iter_empty(buf_iter)) | |
9aba60fe SR |
4578 | return 0; |
4579 | } else { | |
1c5eb448 | 4580 | if (!ring_buffer_empty_cpu(iter->array_buffer->buffer, cpu)) |
9aba60fe SR |
4581 | return 0; |
4582 | } | |
4583 | return 1; | |
4584 | } | |
4585 | ||
ab46428c | 4586 | for_each_tracing_cpu(cpu) { |
6d158a81 SR |
4587 | buf_iter = trace_buffer_iter(iter, cpu); |
4588 | if (buf_iter) { | |
4589 | if (!ring_buffer_iter_empty(buf_iter)) | |
d769041f SR |
4590 | return 0; |
4591 | } else { | |
1c5eb448 | 4592 | if (!ring_buffer_empty_cpu(iter->array_buffer->buffer, cpu)) |
d769041f SR |
4593 | return 0; |
4594 | } | |
bc0c38d1 | 4595 | } |
d769041f | 4596 | |
797d3712 | 4597 | return 1; |
bc0c38d1 SR |
4598 | } |
4599 | ||
4f535968 | 4600 | /* Called with trace_event_read_lock() held. */ |
955b61e5 | 4601 | enum print_line_t print_trace_line(struct trace_iterator *iter) |
f9896bf3 | 4602 | { |
983f938a SRRH |
4603 | struct trace_array *tr = iter->tr; |
4604 | unsigned long trace_flags = tr->trace_flags; | |
2c4f035f FW |
4605 | enum print_line_t ret; |
4606 | ||
19a7fe20 | 4607 | if (iter->lost_events) { |
c9b7a4a7 SRV |
4608 | if (iter->lost_events == (unsigned long)-1) |
4609 | trace_seq_printf(&iter->seq, "CPU:%d [LOST EVENTS]\n", | |
4610 | iter->cpu); | |
4611 | else | |
4612 | trace_seq_printf(&iter->seq, "CPU:%d [LOST %lu EVENTS]\n", | |
4613 | iter->cpu, iter->lost_events); | |
19a7fe20 SRRH |
4614 | if (trace_seq_has_overflowed(&iter->seq)) |
4615 | return TRACE_TYPE_PARTIAL_LINE; | |
4616 | } | |
bc21b478 | 4617 | |
2c4f035f FW |
4618 | if (iter->trace && iter->trace->print_line) { |
4619 | ret = iter->trace->print_line(iter); | |
4620 | if (ret != TRACE_TYPE_UNHANDLED) | |
4621 | return ret; | |
4622 | } | |
72829bc3 | 4623 | |
09ae7234 SRRH |
4624 | if (iter->ent->type == TRACE_BPUTS && |
4625 | trace_flags & TRACE_ITER_PRINTK && | |
4626 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
4627 | return trace_print_bputs_msg_only(iter); | |
4628 | ||
48ead020 FW |
4629 | if (iter->ent->type == TRACE_BPRINT && |
4630 | trace_flags & TRACE_ITER_PRINTK && | |
4631 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
5ef841f6 | 4632 | return trace_print_bprintk_msg_only(iter); |
48ead020 | 4633 | |
66896a85 FW |
4634 | if (iter->ent->type == TRACE_PRINT && |
4635 | trace_flags & TRACE_ITER_PRINTK && | |
4636 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
5ef841f6 | 4637 | return trace_print_printk_msg_only(iter); |
66896a85 | 4638 | |
cb0f12aa IM |
4639 | if (trace_flags & TRACE_ITER_BIN) |
4640 | return print_bin_fmt(iter); | |
4641 | ||
5e3ca0ec IM |
4642 | if (trace_flags & TRACE_ITER_HEX) |
4643 | return print_hex_fmt(iter); | |
4644 | ||
f9896bf3 IM |
4645 | if (trace_flags & TRACE_ITER_RAW) |
4646 | return print_raw_fmt(iter); | |
4647 | ||
f9896bf3 IM |
4648 | return print_trace_fmt(iter); |
4649 | } | |
4650 | ||
7e9a49ef JO |
4651 | void trace_latency_header(struct seq_file *m) |
4652 | { | |
4653 | struct trace_iterator *iter = m->private; | |
983f938a | 4654 | struct trace_array *tr = iter->tr; |
7e9a49ef JO |
4655 | |
4656 | /* print nothing if the buffers are empty */ | |
4657 | if (trace_empty(iter)) | |
4658 | return; | |
4659 | ||
4660 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) | |
4661 | print_trace_header(m, iter); | |
4662 | ||
983f938a | 4663 | if (!(tr->trace_flags & TRACE_ITER_VERBOSE)) |
7e9a49ef JO |
4664 | print_lat_help_header(m); |
4665 | } | |
4666 | ||
62b915f1 JO |
4667 | void trace_default_header(struct seq_file *m) |
4668 | { | |
4669 | struct trace_iterator *iter = m->private; | |
983f938a SRRH |
4670 | struct trace_array *tr = iter->tr; |
4671 | unsigned long trace_flags = tr->trace_flags; | |
62b915f1 | 4672 | |
f56e7f8e JO |
4673 | if (!(trace_flags & TRACE_ITER_CONTEXT_INFO)) |
4674 | return; | |
4675 | ||
62b915f1 JO |
4676 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) { |
4677 | /* print nothing if the buffers are empty */ | |
4678 | if (trace_empty(iter)) | |
4679 | return; | |
4680 | print_trace_header(m, iter); | |
4681 | if (!(trace_flags & TRACE_ITER_VERBOSE)) | |
4682 | print_lat_help_header(m); | |
4683 | } else { | |
77271ce4 SR |
4684 | if (!(trace_flags & TRACE_ITER_VERBOSE)) { |
4685 | if (trace_flags & TRACE_ITER_IRQ_INFO) | |
1c5eb448 | 4686 | print_func_help_header_irq(iter->array_buffer, |
441dae8f | 4687 | m, trace_flags); |
77271ce4 | 4688 | else |
1c5eb448 | 4689 | print_func_help_header(iter->array_buffer, m, |
441dae8f | 4690 | trace_flags); |
77271ce4 | 4691 | } |
62b915f1 JO |
4692 | } |
4693 | } | |
4694 | ||
e0a413f6 SR |
4695 | static void test_ftrace_alive(struct seq_file *m) |
4696 | { | |
4697 | if (!ftrace_is_dead()) | |
4698 | return; | |
d79ac28f RV |
4699 | seq_puts(m, "# WARNING: FUNCTION TRACING IS CORRUPTED\n" |
4700 | "# MAY BE MISSING FUNCTION EVENTS\n"); | |
e0a413f6 SR |
4701 | } |
4702 | ||
d8741e2e | 4703 | #ifdef CONFIG_TRACER_MAX_TRACE |
f1affcaa | 4704 | static void show_snapshot_main_help(struct seq_file *m) |
d8741e2e | 4705 | { |
d79ac28f RV |
4706 | seq_puts(m, "# echo 0 > snapshot : Clears and frees snapshot buffer\n" |
4707 | "# echo 1 > snapshot : Allocates snapshot buffer, if not already allocated.\n" | |
4708 | "# Takes a snapshot of the main buffer.\n" | |
4709 | "# echo 2 > snapshot : Clears snapshot buffer (but does not allocate or free)\n" | |
4710 | "# (Doesn't have to be '2' works with any number that\n" | |
4711 | "# is not a '0' or '1')\n"); | |
d8741e2e | 4712 | } |
f1affcaa SRRH |
4713 | |
4714 | static void show_snapshot_percpu_help(struct seq_file *m) | |
4715 | { | |
fa6f0cc7 | 4716 | seq_puts(m, "# echo 0 > snapshot : Invalid for per_cpu snapshot file.\n"); |
f1affcaa | 4717 | #ifdef CONFIG_RING_BUFFER_ALLOW_SWAP |
d79ac28f RV |
4718 | seq_puts(m, "# echo 1 > snapshot : Allocates snapshot buffer, if not already allocated.\n" |
4719 | "# Takes a snapshot of the main buffer for this cpu.\n"); | |
f1affcaa | 4720 | #else |
d79ac28f RV |
4721 | seq_puts(m, "# echo 1 > snapshot : Not supported with this kernel.\n" |
4722 | "# Must use main snapshot file to allocate.\n"); | |
f1affcaa | 4723 | #endif |
d79ac28f RV |
4724 | seq_puts(m, "# echo 2 > snapshot : Clears this cpu's snapshot buffer (but does not allocate)\n" |
4725 | "# (Doesn't have to be '2' works with any number that\n" | |
4726 | "# is not a '0' or '1')\n"); | |
f1affcaa SRRH |
4727 | } |
4728 | ||
d8741e2e SRRH |
4729 | static void print_snapshot_help(struct seq_file *m, struct trace_iterator *iter) |
4730 | { | |
45ad21ca | 4731 | if (iter->tr->allocated_snapshot) |
fa6f0cc7 | 4732 | seq_puts(m, "#\n# * Snapshot is allocated *\n#\n"); |
d8741e2e | 4733 | else |
fa6f0cc7 | 4734 | seq_puts(m, "#\n# * Snapshot is freed *\n#\n"); |
d8741e2e | 4735 | |
fa6f0cc7 | 4736 | seq_puts(m, "# Snapshot commands:\n"); |
f1affcaa SRRH |
4737 | if (iter->cpu_file == RING_BUFFER_ALL_CPUS) |
4738 | show_snapshot_main_help(m); | |
4739 | else | |
4740 | show_snapshot_percpu_help(m); | |
d8741e2e SRRH |
4741 | } |
4742 | #else | |
4743 | /* Should never be called */ | |
4744 | static inline void print_snapshot_help(struct seq_file *m, struct trace_iterator *iter) { } | |
4745 | #endif | |
4746 | ||
bc0c38d1 SR |
4747 | static int s_show(struct seq_file *m, void *v) |
4748 | { | |
4749 | struct trace_iterator *iter = v; | |
a63ce5b3 | 4750 | int ret; |
bc0c38d1 SR |
4751 | |
4752 | if (iter->ent == NULL) { | |
4753 | if (iter->tr) { | |
4754 | seq_printf(m, "# tracer: %s\n", iter->trace->name); | |
4755 | seq_puts(m, "#\n"); | |
e0a413f6 | 4756 | test_ftrace_alive(m); |
bc0c38d1 | 4757 | } |
d8741e2e SRRH |
4758 | if (iter->snapshot && trace_empty(iter)) |
4759 | print_snapshot_help(m, iter); | |
4760 | else if (iter->trace && iter->trace->print_header) | |
8bba1bf5 | 4761 | iter->trace->print_header(m); |
62b915f1 JO |
4762 | else |
4763 | trace_default_header(m); | |
4764 | ||
a63ce5b3 SR |
4765 | } else if (iter->leftover) { |
4766 | /* | |
4767 | * If we filled the seq_file buffer earlier, we | |
4768 | * want to just show it now. | |
4769 | */ | |
4770 | ret = trace_print_seq(m, &iter->seq); | |
4771 | ||
4772 | /* ret should this time be zero, but you never know */ | |
4773 | iter->leftover = ret; | |
4774 | ||
bc0c38d1 | 4775 | } else { |
f9896bf3 | 4776 | print_trace_line(iter); |
a63ce5b3 SR |
4777 | ret = trace_print_seq(m, &iter->seq); |
4778 | /* | |
4779 | * If we overflow the seq_file buffer, then it will | |
4780 | * ask us for this data again at start up. | |
4781 | * Use that instead. | |
4782 | * ret is 0 if seq_file write succeeded. | |
4783 | * -1 otherwise. | |
4784 | */ | |
4785 | iter->leftover = ret; | |
bc0c38d1 SR |
4786 | } |
4787 | ||
4788 | return 0; | |
4789 | } | |
4790 | ||
649e9c70 ON |
4791 | /* |
4792 | * Should be used after trace_array_get(), trace_types_lock | |
4793 | * ensures that i_cdev was already initialized. | |
4794 | */ | |
4795 | static inline int tracing_get_cpu(struct inode *inode) | |
4796 | { | |
4797 | if (inode->i_cdev) /* See trace_create_cpu_file() */ | |
4798 | return (long)inode->i_cdev - 1; | |
4799 | return RING_BUFFER_ALL_CPUS; | |
4800 | } | |
4801 | ||
88e9d34c | 4802 | static const struct seq_operations tracer_seq_ops = { |
4bf39a94 IM |
4803 | .start = s_start, |
4804 | .next = s_next, | |
4805 | .stop = s_stop, | |
4806 | .show = s_show, | |
bc0c38d1 SR |
4807 | }; |
4808 | ||
6bba9288 SRG |
4809 | /* |
4810 | * Note, as iter itself can be allocated and freed in different | |
4811 | * ways, this function is only used to free its content, and not | |
4812 | * the iterator itself. The only requirement to all the allocations | |
4813 | * is that it must zero all fields (kzalloc), as freeing works with | |
4814 | * ethier allocated content or NULL. | |
4815 | */ | |
4816 | static void free_trace_iter_content(struct trace_iterator *iter) | |
4817 | { | |
4818 | /* The fmt is either NULL, allocated or points to static_fmt_buf */ | |
4819 | if (iter->fmt != static_fmt_buf) | |
4820 | kfree(iter->fmt); | |
4821 | ||
4822 | kfree(iter->temp); | |
4823 | kfree(iter->buffer_iter); | |
4824 | mutex_destroy(&iter->mutex); | |
4825 | free_cpumask_var(iter->started); | |
4826 | } | |
4827 | ||
e309b41d | 4828 | static struct trace_iterator * |
6484c71c | 4829 | __tracing_open(struct inode *inode, struct file *file, bool snapshot) |
bc0c38d1 | 4830 | { |
6484c71c | 4831 | struct trace_array *tr = inode->i_private; |
bc0c38d1 | 4832 | struct trace_iterator *iter; |
50e18b94 | 4833 | int cpu; |
bc0c38d1 | 4834 | |
85a2f9b4 SR |
4835 | if (tracing_disabled) |
4836 | return ERR_PTR(-ENODEV); | |
60a11774 | 4837 | |
50e18b94 | 4838 | iter = __seq_open_private(file, &tracer_seq_ops, sizeof(*iter)); |
85a2f9b4 SR |
4839 | if (!iter) |
4840 | return ERR_PTR(-ENOMEM); | |
bc0c38d1 | 4841 | |
72917235 | 4842 | iter->buffer_iter = kcalloc(nr_cpu_ids, sizeof(*iter->buffer_iter), |
6d158a81 | 4843 | GFP_KERNEL); |
93574fcc DC |
4844 | if (!iter->buffer_iter) |
4845 | goto release; | |
4846 | ||
ff895103 SRV |
4847 | /* |
4848 | * trace_find_next_entry() may need to save off iter->ent. | |
4849 | * It will place it into the iter->temp buffer. As most | |
4850 | * events are less than 128, allocate a buffer of that size. | |
4851 | * If one is greater, then trace_find_next_entry() will | |
4852 | * allocate a new buffer to adjust for the bigger iter->ent. | |
4853 | * It's not critical if it fails to get allocated here. | |
4854 | */ | |
4855 | iter->temp = kmalloc(128, GFP_KERNEL); | |
4856 | if (iter->temp) | |
4857 | iter->temp_size = 128; | |
4858 | ||
efbbdaa2 MH |
4859 | /* |
4860 | * trace_event_printf() may need to modify given format | |
4861 | * string to replace %p with %px so that it shows real address | |
4862 | * instead of hash value. However, that is only for the event | |
4863 | * tracing, other tracer may not need. Defer the allocation | |
4864 | * until it is needed. | |
4865 | */ | |
4866 | iter->fmt = NULL; | |
4867 | iter->fmt_size = 0; | |
4868 | ||
bc0c38d1 | 4869 | mutex_lock(&trace_types_lock); |
9182b519 | 4870 | iter->trace = tr->current_trace; |
d7350c3f | 4871 | |
79f55997 | 4872 | if (!zalloc_cpumask_var(&iter->started, GFP_KERNEL)) |
b0dfa978 FW |
4873 | goto fail; |
4874 | ||
12883efb SRRH |
4875 | iter->tr = tr; |
4876 | ||
4877 | #ifdef CONFIG_TRACER_MAX_TRACE | |
2b6080f2 SR |
4878 | /* Currently only the top directory has a snapshot */ |
4879 | if (tr->current_trace->print_max || snapshot) | |
1c5eb448 | 4880 | iter->array_buffer = &tr->max_buffer; |
bc0c38d1 | 4881 | else |
12883efb | 4882 | #endif |
1c5eb448 | 4883 | iter->array_buffer = &tr->array_buffer; |
debdd57f | 4884 | iter->snapshot = snapshot; |
bc0c38d1 | 4885 | iter->pos = -1; |
6484c71c | 4886 | iter->cpu_file = tracing_get_cpu(inode); |
d7350c3f | 4887 | mutex_init(&iter->mutex); |
bc0c38d1 | 4888 | |
8bba1bf5 | 4889 | /* Notify the tracer early; before we stop tracing. */ |
b3f7a6cd | 4890 | if (iter->trace->open) |
a93751ca | 4891 | iter->trace->open(iter); |
8bba1bf5 | 4892 | |
12ef7d44 | 4893 | /* Annotate start of buffers if we had overruns */ |
1c5eb448 | 4894 | if (ring_buffer_overruns(iter->array_buffer->buffer)) |
12ef7d44 SR |
4895 | iter->iter_flags |= TRACE_FILE_ANNOTATE; |
4896 | ||
8be0709f | 4897 | /* Output in nanoseconds only if we are using a clock in nanoseconds. */ |
58e8eedf | 4898 | if (trace_clocks[tr->clock_id].in_ns) |
8be0709f DS |
4899 | iter->iter_flags |= TRACE_FILE_TIME_IN_NS; |
4900 | ||
06e0a548 SRV |
4901 | /* |
4902 | * If pause-on-trace is enabled, then stop the trace while | |
4903 | * dumping, unless this is the "snapshot" file | |
4904 | */ | |
4905 | if (!iter->snapshot && (tr->trace_flags & TRACE_ITER_PAUSE_ON_TRACE)) | |
2b6080f2 | 4906 | tracing_stop_tr(tr); |
2f26ebd5 | 4907 | |
ae3b5093 | 4908 | if (iter->cpu_file == RING_BUFFER_ALL_CPUS) { |
b04cc6b1 | 4909 | for_each_tracing_cpu(cpu) { |
b04cc6b1 | 4910 | iter->buffer_iter[cpu] = |
1c5eb448 | 4911 | ring_buffer_read_prepare(iter->array_buffer->buffer, |
31b265b3 | 4912 | cpu, GFP_KERNEL); |
72c9ddfd DM |
4913 | } |
4914 | ring_buffer_read_prepare_sync(); | |
4915 | for_each_tracing_cpu(cpu) { | |
4916 | ring_buffer_read_start(iter->buffer_iter[cpu]); | |
2f26ebd5 | 4917 | tracing_iter_reset(iter, cpu); |
b04cc6b1 FW |
4918 | } |
4919 | } else { | |
4920 | cpu = iter->cpu_file; | |
3928a8a2 | 4921 | iter->buffer_iter[cpu] = |
1c5eb448 | 4922 | ring_buffer_read_prepare(iter->array_buffer->buffer, |
31b265b3 | 4923 | cpu, GFP_KERNEL); |
72c9ddfd DM |
4924 | ring_buffer_read_prepare_sync(); |
4925 | ring_buffer_read_start(iter->buffer_iter[cpu]); | |
2f26ebd5 | 4926 | tracing_iter_reset(iter, cpu); |
3928a8a2 SR |
4927 | } |
4928 | ||
bc0c38d1 SR |
4929 | mutex_unlock(&trace_types_lock); |
4930 | ||
bc0c38d1 | 4931 | return iter; |
3928a8a2 | 4932 | |
d7350c3f | 4933 | fail: |
3928a8a2 | 4934 | mutex_unlock(&trace_types_lock); |
6bba9288 | 4935 | free_trace_iter_content(iter); |
93574fcc | 4936 | release: |
50e18b94 JO |
4937 | seq_release_private(inode, file); |
4938 | return ERR_PTR(-ENOMEM); | |
bc0c38d1 SR |
4939 | } |
4940 | ||
4941 | int tracing_open_generic(struct inode *inode, struct file *filp) | |
4942 | { | |
8530dec6 SRV |
4943 | int ret; |
4944 | ||
4945 | ret = tracing_check_open_get_tr(NULL); | |
4946 | if (ret) | |
4947 | return ret; | |
60a11774 | 4948 | |
bc0c38d1 SR |
4949 | filp->private_data = inode->i_private; |
4950 | return 0; | |
4951 | } | |
4952 | ||
2e86421d GB |
4953 | bool tracing_is_disabled(void) |
4954 | { | |
4955 | return (tracing_disabled) ? true: false; | |
4956 | } | |
4957 | ||
7b85af63 SRRH |
4958 | /* |
4959 | * Open and update trace_array ref count. | |
4960 | * Must have the current trace_array passed to it. | |
4961 | */ | |
aa07d71f | 4962 | int tracing_open_generic_tr(struct inode *inode, struct file *filp) |
7b85af63 SRRH |
4963 | { |
4964 | struct trace_array *tr = inode->i_private; | |
8530dec6 | 4965 | int ret; |
7b85af63 | 4966 | |
8530dec6 SRV |
4967 | ret = tracing_check_open_get_tr(tr); |
4968 | if (ret) | |
4969 | return ret; | |
7b85af63 SRRH |
4970 | |
4971 | filp->private_data = inode->i_private; | |
4972 | ||
4973 | return 0; | |
7b85af63 SRRH |
4974 | } |
4975 | ||
f5ca233e SRG |
4976 | /* |
4977 | * The private pointer of the inode is the trace_event_file. | |
4978 | * Update the tr ref count associated to it. | |
4979 | */ | |
4980 | int tracing_open_file_tr(struct inode *inode, struct file *filp) | |
4981 | { | |
4982 | struct trace_event_file *file = inode->i_private; | |
4983 | int ret; | |
4984 | ||
4985 | ret = tracing_check_open_get_tr(file->tr); | |
4986 | if (ret) | |
4987 | return ret; | |
4988 | ||
4989 | filp->private_data = inode->i_private; | |
4990 | ||
4991 | return 0; | |
4992 | } | |
4993 | ||
4994 | int tracing_release_file_tr(struct inode *inode, struct file *filp) | |
4995 | { | |
4996 | struct trace_event_file *file = inode->i_private; | |
4997 | ||
4998 | trace_array_put(file->tr); | |
4999 | ||
5000 | return 0; | |
5001 | } | |
5002 | ||
2972e305 JK |
5003 | static int tracing_mark_open(struct inode *inode, struct file *filp) |
5004 | { | |
5005 | stream_open(inode, filp); | |
5006 | return tracing_open_generic_tr(inode, filp); | |
5007 | } | |
5008 | ||
4fd27358 | 5009 | static int tracing_release(struct inode *inode, struct file *file) |
bc0c38d1 | 5010 | { |
6484c71c | 5011 | struct trace_array *tr = inode->i_private; |
907f2784 | 5012 | struct seq_file *m = file->private_data; |
4acd4d00 | 5013 | struct trace_iterator *iter; |
3928a8a2 | 5014 | int cpu; |
bc0c38d1 | 5015 | |
ff451961 | 5016 | if (!(file->f_mode & FMODE_READ)) { |
6484c71c | 5017 | trace_array_put(tr); |
4acd4d00 | 5018 | return 0; |
ff451961 | 5019 | } |
4acd4d00 | 5020 | |
6484c71c | 5021 | /* Writes do not use seq_file */ |
4acd4d00 | 5022 | iter = m->private; |
bc0c38d1 | 5023 | mutex_lock(&trace_types_lock); |
a695cb58 | 5024 | |
3928a8a2 SR |
5025 | for_each_tracing_cpu(cpu) { |
5026 | if (iter->buffer_iter[cpu]) | |
5027 | ring_buffer_read_finish(iter->buffer_iter[cpu]); | |
5028 | } | |
5029 | ||
bc0c38d1 SR |
5030 | if (iter->trace && iter->trace->close) |
5031 | iter->trace->close(iter); | |
5032 | ||
06e0a548 | 5033 | if (!iter->snapshot && tr->stop_count) |
debdd57f | 5034 | /* reenable tracing if it was previously enabled */ |
2b6080f2 | 5035 | tracing_start_tr(tr); |
f77d09a3 AL |
5036 | |
5037 | __trace_array_put(tr); | |
5038 | ||
bc0c38d1 SR |
5039 | mutex_unlock(&trace_types_lock); |
5040 | ||
6bba9288 | 5041 | free_trace_iter_content(iter); |
50e18b94 | 5042 | seq_release_private(inode, file); |
ff451961 | 5043 | |
bc0c38d1 SR |
5044 | return 0; |
5045 | } | |
5046 | ||
7b85af63 SRRH |
5047 | static int tracing_release_generic_tr(struct inode *inode, struct file *file) |
5048 | { | |
5049 | struct trace_array *tr = inode->i_private; | |
5050 | ||
5051 | trace_array_put(tr); | |
bc0c38d1 SR |
5052 | return 0; |
5053 | } | |
5054 | ||
7b85af63 SRRH |
5055 | static int tracing_single_release_tr(struct inode *inode, struct file *file) |
5056 | { | |
5057 | struct trace_array *tr = inode->i_private; | |
5058 | ||
5059 | trace_array_put(tr); | |
5060 | ||
5061 | return single_release(inode, file); | |
5062 | } | |
5063 | ||
bc0c38d1 SR |
5064 | static int tracing_open(struct inode *inode, struct file *file) |
5065 | { | |
6484c71c | 5066 | struct trace_array *tr = inode->i_private; |
85a2f9b4 | 5067 | struct trace_iterator *iter; |
8530dec6 | 5068 | int ret; |
bc0c38d1 | 5069 | |
8530dec6 SRV |
5070 | ret = tracing_check_open_get_tr(tr); |
5071 | if (ret) | |
5072 | return ret; | |
ff451961 | 5073 | |
4acd4d00 | 5074 | /* If this file was open for write, then erase contents */ |
6484c71c ON |
5075 | if ((file->f_mode & FMODE_WRITE) && (file->f_flags & O_TRUNC)) { |
5076 | int cpu = tracing_get_cpu(inode); | |
1c5eb448 | 5077 | struct array_buffer *trace_buf = &tr->array_buffer; |
8dd33bcb BY |
5078 | |
5079 | #ifdef CONFIG_TRACER_MAX_TRACE | |
5080 | if (tr->current_trace->print_max) | |
5081 | trace_buf = &tr->max_buffer; | |
5082 | #endif | |
6484c71c ON |
5083 | |
5084 | if (cpu == RING_BUFFER_ALL_CPUS) | |
8dd33bcb | 5085 | tracing_reset_online_cpus(trace_buf); |
4acd4d00 | 5086 | else |
a47b53e9 | 5087 | tracing_reset_cpu(trace_buf, cpu); |
4acd4d00 | 5088 | } |
bc0c38d1 | 5089 | |
4acd4d00 | 5090 | if (file->f_mode & FMODE_READ) { |
6484c71c | 5091 | iter = __tracing_open(inode, file, false); |
4acd4d00 SR |
5092 | if (IS_ERR(iter)) |
5093 | ret = PTR_ERR(iter); | |
983f938a | 5094 | else if (tr->trace_flags & TRACE_ITER_LATENCY_FMT) |
4acd4d00 SR |
5095 | iter->iter_flags |= TRACE_FILE_LAT_FMT; |
5096 | } | |
ff451961 SRRH |
5097 | |
5098 | if (ret < 0) | |
5099 | trace_array_put(tr); | |
5100 | ||
bc0c38d1 SR |
5101 | return ret; |
5102 | } | |
5103 | ||
607e2ea1 SRRH |
5104 | /* |
5105 | * Some tracers are not suitable for instance buffers. | |
5106 | * A tracer is always available for the global array (toplevel) | |
5107 | * or if it explicitly states that it is. | |
5108 | */ | |
5109 | static bool | |
5110 | trace_ok_for_array(struct tracer *t, struct trace_array *tr) | |
5111 | { | |
5112 | return (tr->flags & TRACE_ARRAY_FL_GLOBAL) || t->allow_instances; | |
5113 | } | |
5114 | ||
5115 | /* Find the next tracer that this trace array may use */ | |
5116 | static struct tracer * | |
5117 | get_tracer_for_array(struct trace_array *tr, struct tracer *t) | |
5118 | { | |
5119 | while (t && !trace_ok_for_array(t, tr)) | |
5120 | t = t->next; | |
5121 | ||
5122 | return t; | |
5123 | } | |
5124 | ||
e309b41d | 5125 | static void * |
bc0c38d1 SR |
5126 | t_next(struct seq_file *m, void *v, loff_t *pos) |
5127 | { | |
607e2ea1 | 5128 | struct trace_array *tr = m->private; |
f129e965 | 5129 | struct tracer *t = v; |
bc0c38d1 SR |
5130 | |
5131 | (*pos)++; | |
5132 | ||
5133 | if (t) | |
607e2ea1 | 5134 | t = get_tracer_for_array(tr, t->next); |
bc0c38d1 | 5135 | |
bc0c38d1 SR |
5136 | return t; |
5137 | } | |
5138 | ||
5139 | static void *t_start(struct seq_file *m, loff_t *pos) | |
5140 | { | |
607e2ea1 | 5141 | struct trace_array *tr = m->private; |
f129e965 | 5142 | struct tracer *t; |
bc0c38d1 SR |
5143 | loff_t l = 0; |
5144 | ||
5145 | mutex_lock(&trace_types_lock); | |
607e2ea1 SRRH |
5146 | |
5147 | t = get_tracer_for_array(tr, trace_types); | |
5148 | for (; t && l < *pos; t = t_next(m, t, &l)) | |
5149 | ; | |
bc0c38d1 SR |
5150 | |
5151 | return t; | |
5152 | } | |
5153 | ||
5154 | static void t_stop(struct seq_file *m, void *p) | |
5155 | { | |
5156 | mutex_unlock(&trace_types_lock); | |
5157 | } | |
5158 | ||
5159 | static int t_show(struct seq_file *m, void *v) | |
5160 | { | |
5161 | struct tracer *t = v; | |
5162 | ||
5163 | if (!t) | |
5164 | return 0; | |
5165 | ||
fa6f0cc7 | 5166 | seq_puts(m, t->name); |
bc0c38d1 SR |
5167 | if (t->next) |
5168 | seq_putc(m, ' '); | |
5169 | else | |
5170 | seq_putc(m, '\n'); | |
5171 | ||
5172 | return 0; | |
5173 | } | |
5174 | ||
88e9d34c | 5175 | static const struct seq_operations show_traces_seq_ops = { |
4bf39a94 IM |
5176 | .start = t_start, |
5177 | .next = t_next, | |
5178 | .stop = t_stop, | |
5179 | .show = t_show, | |
bc0c38d1 SR |
5180 | }; |
5181 | ||
5182 | static int show_traces_open(struct inode *inode, struct file *file) | |
5183 | { | |
607e2ea1 SRRH |
5184 | struct trace_array *tr = inode->i_private; |
5185 | struct seq_file *m; | |
5186 | int ret; | |
5187 | ||
8530dec6 SRV |
5188 | ret = tracing_check_open_get_tr(tr); |
5189 | if (ret) | |
5190 | return ret; | |
194c2c74 | 5191 | |
607e2ea1 | 5192 | ret = seq_open(file, &show_traces_seq_ops); |
194c2c74 SRV |
5193 | if (ret) { |
5194 | trace_array_put(tr); | |
607e2ea1 | 5195 | return ret; |
194c2c74 | 5196 | } |
607e2ea1 SRRH |
5197 | |
5198 | m = file->private_data; | |
5199 | m->private = tr; | |
5200 | ||
5201 | return 0; | |
bc0c38d1 SR |
5202 | } |
5203 | ||
194c2c74 SRV |
5204 | static int show_traces_release(struct inode *inode, struct file *file) |
5205 | { | |
5206 | struct trace_array *tr = inode->i_private; | |
5207 | ||
5208 | trace_array_put(tr); | |
5209 | return seq_release(inode, file); | |
5210 | } | |
5211 | ||
4acd4d00 SR |
5212 | static ssize_t |
5213 | tracing_write_stub(struct file *filp, const char __user *ubuf, | |
5214 | size_t count, loff_t *ppos) | |
5215 | { | |
5216 | return count; | |
5217 | } | |
5218 | ||
098c879e | 5219 | loff_t tracing_lseek(struct file *file, loff_t offset, int whence) |
364829b1 | 5220 | { |
098c879e SRRH |
5221 | int ret; |
5222 | ||
364829b1 | 5223 | if (file->f_mode & FMODE_READ) |
098c879e | 5224 | ret = seq_lseek(file, offset, whence); |
364829b1 | 5225 | else |
098c879e SRRH |
5226 | file->f_pos = ret = 0; |
5227 | ||
5228 | return ret; | |
364829b1 SP |
5229 | } |
5230 | ||
5e2336a0 | 5231 | static const struct file_operations tracing_fops = { |
4bf39a94 IM |
5232 | .open = tracing_open, |
5233 | .read = seq_read, | |
e400be67 | 5234 | .read_iter = seq_read_iter, |
5bd4990f | 5235 | .splice_read = copy_splice_read, |
4acd4d00 | 5236 | .write = tracing_write_stub, |
098c879e | 5237 | .llseek = tracing_lseek, |
4bf39a94 | 5238 | .release = tracing_release, |
bc0c38d1 SR |
5239 | }; |
5240 | ||
5e2336a0 | 5241 | static const struct file_operations show_traces_fops = { |
c7078de1 IM |
5242 | .open = show_traces_open, |
5243 | .read = seq_read, | |
b444786f | 5244 | .llseek = seq_lseek, |
194c2c74 | 5245 | .release = show_traces_release, |
c7078de1 IM |
5246 | }; |
5247 | ||
5248 | static ssize_t | |
5249 | tracing_cpumask_read(struct file *filp, char __user *ubuf, | |
5250 | size_t count, loff_t *ppos) | |
5251 | { | |
ccfe9e42 | 5252 | struct trace_array *tr = file_inode(filp)->i_private; |
90e406f9 | 5253 | char *mask_str; |
36dfe925 | 5254 | int len; |
c7078de1 | 5255 | |
90e406f9 CD |
5256 | len = snprintf(NULL, 0, "%*pb\n", |
5257 | cpumask_pr_args(tr->tracing_cpumask)) + 1; | |
5258 | mask_str = kmalloc(len, GFP_KERNEL); | |
5259 | if (!mask_str) | |
5260 | return -ENOMEM; | |
36dfe925 | 5261 | |
90e406f9 | 5262 | len = snprintf(mask_str, len, "%*pb\n", |
1a40243b TH |
5263 | cpumask_pr_args(tr->tracing_cpumask)); |
5264 | if (len >= count) { | |
36dfe925 IM |
5265 | count = -EINVAL; |
5266 | goto out_err; | |
5267 | } | |
90e406f9 | 5268 | count = simple_read_from_buffer(ubuf, count, ppos, mask_str, len); |
36dfe925 IM |
5269 | |
5270 | out_err: | |
90e406f9 | 5271 | kfree(mask_str); |
c7078de1 IM |
5272 | |
5273 | return count; | |
5274 | } | |
5275 | ||
9d15dbbd MH |
5276 | int tracing_set_cpumask(struct trace_array *tr, |
5277 | cpumask_var_t tracing_cpumask_new) | |
c7078de1 | 5278 | { |
9d15dbbd | 5279 | int cpu; |
c7078de1 | 5280 | |
9d15dbbd MH |
5281 | if (!tr) |
5282 | return -EINVAL; | |
36dfe925 | 5283 | |
a5e25883 | 5284 | local_irq_disable(); |
0b9b12c1 | 5285 | arch_spin_lock(&tr->max_lock); |
ab46428c | 5286 | for_each_tracing_cpu(cpu) { |
36dfe925 IM |
5287 | /* |
5288 | * Increase/decrease the disabled counter if we are | |
5289 | * about to flip a bit in the cpumask: | |
5290 | */ | |
ccfe9e42 | 5291 | if (cpumask_test_cpu(cpu, tr->tracing_cpumask) && |
9e01c1b7 | 5292 | !cpumask_test_cpu(cpu, tracing_cpumask_new)) { |
1c5eb448 SRV |
5293 | atomic_inc(&per_cpu_ptr(tr->array_buffer.data, cpu)->disabled); |
5294 | ring_buffer_record_disable_cpu(tr->array_buffer.buffer, cpu); | |
b71645d6 ZY |
5295 | #ifdef CONFIG_TRACER_MAX_TRACE |
5296 | ring_buffer_record_disable_cpu(tr->max_buffer.buffer, cpu); | |
5297 | #endif | |
36dfe925 | 5298 | } |
ccfe9e42 | 5299 | if (!cpumask_test_cpu(cpu, tr->tracing_cpumask) && |
9e01c1b7 | 5300 | cpumask_test_cpu(cpu, tracing_cpumask_new)) { |
1c5eb448 SRV |
5301 | atomic_dec(&per_cpu_ptr(tr->array_buffer.data, cpu)->disabled); |
5302 | ring_buffer_record_enable_cpu(tr->array_buffer.buffer, cpu); | |
b71645d6 ZY |
5303 | #ifdef CONFIG_TRACER_MAX_TRACE |
5304 | ring_buffer_record_enable_cpu(tr->max_buffer.buffer, cpu); | |
5305 | #endif | |
36dfe925 IM |
5306 | } |
5307 | } | |
0b9b12c1 | 5308 | arch_spin_unlock(&tr->max_lock); |
a5e25883 | 5309 | local_irq_enable(); |
36dfe925 | 5310 | |
ccfe9e42 | 5311 | cpumask_copy(tr->tracing_cpumask, tracing_cpumask_new); |
9d15dbbd MH |
5312 | |
5313 | return 0; | |
5314 | } | |
5315 | ||
5316 | static ssize_t | |
5317 | tracing_cpumask_write(struct file *filp, const char __user *ubuf, | |
5318 | size_t count, loff_t *ppos) | |
5319 | { | |
5320 | struct trace_array *tr = file_inode(filp)->i_private; | |
5321 | cpumask_var_t tracing_cpumask_new; | |
5322 | int err; | |
5323 | ||
c5e3a411 | 5324 | if (!zalloc_cpumask_var(&tracing_cpumask_new, GFP_KERNEL)) |
9d15dbbd MH |
5325 | return -ENOMEM; |
5326 | ||
5327 | err = cpumask_parse_user(ubuf, count, tracing_cpumask_new); | |
5328 | if (err) | |
5329 | goto err_free; | |
5330 | ||
5331 | err = tracing_set_cpumask(tr, tracing_cpumask_new); | |
5332 | if (err) | |
5333 | goto err_free; | |
5334 | ||
9e01c1b7 | 5335 | free_cpumask_var(tracing_cpumask_new); |
c7078de1 IM |
5336 | |
5337 | return count; | |
36dfe925 | 5338 | |
9d15dbbd | 5339 | err_free: |
215368e8 | 5340 | free_cpumask_var(tracing_cpumask_new); |
36dfe925 IM |
5341 | |
5342 | return err; | |
c7078de1 IM |
5343 | } |
5344 | ||
5e2336a0 | 5345 | static const struct file_operations tracing_cpumask_fops = { |
ccfe9e42 | 5346 | .open = tracing_open_generic_tr, |
c7078de1 IM |
5347 | .read = tracing_cpumask_read, |
5348 | .write = tracing_cpumask_write, | |
ccfe9e42 | 5349 | .release = tracing_release_generic_tr, |
b444786f | 5350 | .llseek = generic_file_llseek, |
bc0c38d1 SR |
5351 | }; |
5352 | ||
fdb372ed | 5353 | static int tracing_trace_options_show(struct seq_file *m, void *v) |
bc0c38d1 | 5354 | { |
d8e83d26 | 5355 | struct tracer_opt *trace_opts; |
2b6080f2 | 5356 | struct trace_array *tr = m->private; |
d8e83d26 | 5357 | u32 tracer_flags; |
d8e83d26 | 5358 | int i; |
adf9f195 | 5359 | |
d8e83d26 | 5360 | mutex_lock(&trace_types_lock); |
2b6080f2 SR |
5361 | tracer_flags = tr->current_trace->flags->val; |
5362 | trace_opts = tr->current_trace->flags->opts; | |
d8e83d26 | 5363 | |
bc0c38d1 | 5364 | for (i = 0; trace_options[i]; i++) { |
983f938a | 5365 | if (tr->trace_flags & (1 << i)) |
fdb372ed | 5366 | seq_printf(m, "%s\n", trace_options[i]); |
bc0c38d1 | 5367 | else |
fdb372ed | 5368 | seq_printf(m, "no%s\n", trace_options[i]); |
bc0c38d1 SR |
5369 | } |
5370 | ||
adf9f195 FW |
5371 | for (i = 0; trace_opts[i].name; i++) { |
5372 | if (tracer_flags & trace_opts[i].bit) | |
fdb372ed | 5373 | seq_printf(m, "%s\n", trace_opts[i].name); |
adf9f195 | 5374 | else |
fdb372ed | 5375 | seq_printf(m, "no%s\n", trace_opts[i].name); |
adf9f195 | 5376 | } |
d8e83d26 | 5377 | mutex_unlock(&trace_types_lock); |
adf9f195 | 5378 | |
fdb372ed | 5379 | return 0; |
bc0c38d1 | 5380 | } |
bc0c38d1 | 5381 | |
8c1a49ae | 5382 | static int __set_tracer_option(struct trace_array *tr, |
8d18eaaf LZ |
5383 | struct tracer_flags *tracer_flags, |
5384 | struct tracer_opt *opts, int neg) | |
5385 | { | |
d39cdd20 | 5386 | struct tracer *trace = tracer_flags->trace; |
8d18eaaf | 5387 | int ret; |
bc0c38d1 | 5388 | |
8c1a49ae | 5389 | ret = trace->set_flag(tr, tracer_flags->val, opts->bit, !neg); |
8d18eaaf LZ |
5390 | if (ret) |
5391 | return ret; | |
5392 | ||
5393 | if (neg) | |
5394 | tracer_flags->val &= ~opts->bit; | |
5395 | else | |
5396 | tracer_flags->val |= opts->bit; | |
5397 | return 0; | |
bc0c38d1 SR |
5398 | } |
5399 | ||
adf9f195 | 5400 | /* Try to assign a tracer specific option */ |
8c1a49ae | 5401 | static int set_tracer_option(struct trace_array *tr, char *cmp, int neg) |
adf9f195 | 5402 | { |
8c1a49ae | 5403 | struct tracer *trace = tr->current_trace; |
7770841e | 5404 | struct tracer_flags *tracer_flags = trace->flags; |
adf9f195 | 5405 | struct tracer_opt *opts = NULL; |
8d18eaaf | 5406 | int i; |
adf9f195 | 5407 | |
7770841e Z |
5408 | for (i = 0; tracer_flags->opts[i].name; i++) { |
5409 | opts = &tracer_flags->opts[i]; | |
adf9f195 | 5410 | |
8d18eaaf | 5411 | if (strcmp(cmp, opts->name) == 0) |
8c1a49ae | 5412 | return __set_tracer_option(tr, trace->flags, opts, neg); |
adf9f195 | 5413 | } |
adf9f195 | 5414 | |
8d18eaaf | 5415 | return -EINVAL; |
adf9f195 FW |
5416 | } |
5417 | ||
613f04a0 SRRH |
5418 | /* Some tracers require overwrite to stay enabled */ |
5419 | int trace_keep_overwrite(struct tracer *tracer, u32 mask, int set) | |
5420 | { | |
5421 | if (tracer->enabled && (mask & TRACE_ITER_OVERWRITE) && !set) | |
5422 | return -1; | |
5423 | ||
5424 | return 0; | |
5425 | } | |
5426 | ||
2b6080f2 | 5427 | int set_tracer_flag(struct trace_array *tr, unsigned int mask, int enabled) |
af4617bd | 5428 | { |
4030a6e6 PB |
5429 | int *map; |
5430 | ||
3a53acf1 PS |
5431 | if ((mask == TRACE_ITER_RECORD_TGID) || |
5432 | (mask == TRACE_ITER_RECORD_CMD)) | |
5433 | lockdep_assert_held(&event_mutex); | |
5434 | ||
af4617bd | 5435 | /* do nothing if flag is already set */ |
983f938a | 5436 | if (!!(tr->trace_flags & mask) == !!enabled) |
613f04a0 SRRH |
5437 | return 0; |
5438 | ||
5439 | /* Give the tracer a chance to approve the change */ | |
2b6080f2 | 5440 | if (tr->current_trace->flag_changed) |
bf6065b5 | 5441 | if (tr->current_trace->flag_changed(tr, mask, !!enabled)) |
613f04a0 | 5442 | return -EINVAL; |
af4617bd SR |
5443 | |
5444 | if (enabled) | |
983f938a | 5445 | tr->trace_flags |= mask; |
af4617bd | 5446 | else |
983f938a | 5447 | tr->trace_flags &= ~mask; |
e870e9a1 LZ |
5448 | |
5449 | if (mask == TRACE_ITER_RECORD_CMD) | |
5450 | trace_event_enable_cmd_record(enabled); | |
750912fa | 5451 | |
d914ba37 | 5452 | if (mask == TRACE_ITER_RECORD_TGID) { |
4030a6e6 PB |
5453 | if (!tgid_map) { |
5454 | tgid_map_max = pid_max; | |
5455 | map = kvcalloc(tgid_map_max + 1, sizeof(*tgid_map), | |
5456 | GFP_KERNEL); | |
5457 | ||
5458 | /* | |
5459 | * Pairs with smp_load_acquire() in | |
5460 | * trace_find_tgid_ptr() to ensure that if it observes | |
5461 | * the tgid_map we just allocated then it also observes | |
5462 | * the corresponding tgid_map_max value. | |
5463 | */ | |
5464 | smp_store_release(&tgid_map, map); | |
5465 | } | |
d914ba37 JF |
5466 | if (!tgid_map) { |
5467 | tr->trace_flags &= ~TRACE_ITER_RECORD_TGID; | |
5468 | return -ENOMEM; | |
5469 | } | |
5470 | ||
5471 | trace_event_enable_tgid_record(enabled); | |
5472 | } | |
5473 | ||
c37775d5 SR |
5474 | if (mask == TRACE_ITER_EVENT_FORK) |
5475 | trace_event_follow_fork(tr, enabled); | |
5476 | ||
1e10486f NK |
5477 | if (mask == TRACE_ITER_FUNC_FORK) |
5478 | ftrace_pid_follow_fork(tr, enabled); | |
5479 | ||
80902822 | 5480 | if (mask == TRACE_ITER_OVERWRITE) { |
1c5eb448 | 5481 | ring_buffer_change_overwrite(tr->array_buffer.buffer, enabled); |
80902822 | 5482 | #ifdef CONFIG_TRACER_MAX_TRACE |
12883efb | 5483 | ring_buffer_change_overwrite(tr->max_buffer.buffer, enabled); |
80902822 SRRH |
5484 | #endif |
5485 | } | |
81698831 | 5486 | |
b9f9108c | 5487 | if (mask == TRACE_ITER_PRINTK) { |
81698831 | 5488 | trace_printk_start_stop_comm(enabled); |
b9f9108c SRRH |
5489 | trace_printk_control(enabled); |
5490 | } | |
613f04a0 SRRH |
5491 | |
5492 | return 0; | |
af4617bd SR |
5493 | } |
5494 | ||
9c5b9d3d | 5495 | int trace_set_options(struct trace_array *tr, char *option) |
bc0c38d1 | 5496 | { |
8d18eaaf | 5497 | char *cmp; |
bc0c38d1 | 5498 | int neg = 0; |
591a033d | 5499 | int ret; |
a4d1e688 | 5500 | size_t orig_len = strlen(option); |
3d739c1f | 5501 | int len; |
bc0c38d1 | 5502 | |
7bcfaf54 | 5503 | cmp = strstrip(option); |
bc0c38d1 | 5504 | |
3d739c1f SRV |
5505 | len = str_has_prefix(cmp, "no"); |
5506 | if (len) | |
bc0c38d1 | 5507 | neg = 1; |
3d739c1f SRV |
5508 | |
5509 | cmp += len; | |
bc0c38d1 | 5510 | |
3a53acf1 | 5511 | mutex_lock(&event_mutex); |
69d34da2 SRRH |
5512 | mutex_lock(&trace_types_lock); |
5513 | ||
591a033d | 5514 | ret = match_string(trace_options, -1, cmp); |
adf9f195 | 5515 | /* If no option could be set, test the specific tracer options */ |
591a033d | 5516 | if (ret < 0) |
8c1a49ae | 5517 | ret = set_tracer_option(tr, cmp, neg); |
591a033d YX |
5518 | else |
5519 | ret = set_tracer_flag(tr, 1 << ret, !neg); | |
69d34da2 SRRH |
5520 | |
5521 | mutex_unlock(&trace_types_lock); | |
3a53acf1 | 5522 | mutex_unlock(&event_mutex); |
bc0c38d1 | 5523 | |
a4d1e688 JW |
5524 | /* |
5525 | * If the first trailing whitespace is replaced with '\0' by strstrip, | |
5526 | * turn it back into a space. | |
5527 | */ | |
5528 | if (orig_len > strlen(option)) | |
5529 | option[strlen(option)] = ' '; | |
5530 | ||
7bcfaf54 SR |
5531 | return ret; |
5532 | } | |
5533 | ||
a4d1e688 JW |
5534 | static void __init apply_trace_boot_options(void) |
5535 | { | |
5536 | char *buf = trace_boot_options_buf; | |
5537 | char *option; | |
5538 | ||
5539 | while (true) { | |
5540 | option = strsep(&buf, ","); | |
5541 | ||
5542 | if (!option) | |
5543 | break; | |
a4d1e688 | 5544 | |
43ed3843 SRRH |
5545 | if (*option) |
5546 | trace_set_options(&global_trace, option); | |
a4d1e688 JW |
5547 | |
5548 | /* Put back the comma to allow this to be called again */ | |
5549 | if (buf) | |
5550 | *(buf - 1) = ','; | |
5551 | } | |
5552 | } | |
5553 | ||
7bcfaf54 SR |
5554 | static ssize_t |
5555 | tracing_trace_options_write(struct file *filp, const char __user *ubuf, | |
5556 | size_t cnt, loff_t *ppos) | |
5557 | { | |
2b6080f2 SR |
5558 | struct seq_file *m = filp->private_data; |
5559 | struct trace_array *tr = m->private; | |
7bcfaf54 | 5560 | char buf[64]; |
613f04a0 | 5561 | int ret; |
7bcfaf54 SR |
5562 | |
5563 | if (cnt >= sizeof(buf)) | |
5564 | return -EINVAL; | |
5565 | ||
4afe6495 | 5566 | if (copy_from_user(buf, ubuf, cnt)) |
7bcfaf54 SR |
5567 | return -EFAULT; |
5568 | ||
a8dd2176 SR |
5569 | buf[cnt] = 0; |
5570 | ||
2b6080f2 | 5571 | ret = trace_set_options(tr, buf); |
613f04a0 SRRH |
5572 | if (ret < 0) |
5573 | return ret; | |
7bcfaf54 | 5574 | |
cf8517cf | 5575 | *ppos += cnt; |
bc0c38d1 SR |
5576 | |
5577 | return cnt; | |
5578 | } | |
5579 | ||
fdb372ed LZ |
5580 | static int tracing_trace_options_open(struct inode *inode, struct file *file) |
5581 | { | |
7b85af63 | 5582 | struct trace_array *tr = inode->i_private; |
f77d09a3 | 5583 | int ret; |
7b85af63 | 5584 | |
8530dec6 SRV |
5585 | ret = tracing_check_open_get_tr(tr); |
5586 | if (ret) | |
5587 | return ret; | |
7b85af63 | 5588 | |
f77d09a3 AL |
5589 | ret = single_open(file, tracing_trace_options_show, inode->i_private); |
5590 | if (ret < 0) | |
5591 | trace_array_put(tr); | |
5592 | ||
5593 | return ret; | |
fdb372ed LZ |
5594 | } |
5595 | ||
5e2336a0 | 5596 | static const struct file_operations tracing_iter_fops = { |
fdb372ed LZ |
5597 | .open = tracing_trace_options_open, |
5598 | .read = seq_read, | |
5599 | .llseek = seq_lseek, | |
7b85af63 | 5600 | .release = tracing_single_release_tr, |
ee6bce52 | 5601 | .write = tracing_trace_options_write, |
bc0c38d1 SR |
5602 | }; |
5603 | ||
7bd2f24c IM |
5604 | static const char readme_msg[] = |
5605 | "tracing mini-HOWTO:\n\n" | |
22f45649 SRRH |
5606 | "# echo 0 > tracing_on : quick way to disable tracing\n" |
5607 | "# echo 1 > tracing_on : quick way to re-enable tracing\n\n" | |
5608 | " Important files:\n" | |
5609 | " trace\t\t\t- The static contents of the buffer\n" | |
5610 | "\t\t\t To clear the buffer write into this file: echo > trace\n" | |
5611 | " trace_pipe\t\t- A consuming read to see the contents of the buffer\n" | |
5612 | " current_tracer\t- function and latency tracers\n" | |
5613 | " available_tracers\t- list of configured tracers for current_tracer\n" | |
a8d65579 | 5614 | " error_log\t- error log for failed commands (that support it)\n" |
22f45649 SRRH |
5615 | " buffer_size_kb\t- view and modify size of per cpu buffer\n" |
5616 | " buffer_total_size_kb - view total size of all cpu buffers\n\n" | |
cf2adec7 | 5617 | " trace_clock\t\t- change the clock used to order events\n" |
22f45649 SRRH |
5618 | " local: Per cpu clock but may not be synced across CPUs\n" |
5619 | " global: Synced across CPUs but slows tracing down.\n" | |
5620 | " counter: Not a clock, but just an increment\n" | |
5621 | " uptime: Jiffy counter from time of boot\n" | |
5622 | " perf: Same clock that perf events use\n" | |
5623 | #ifdef CONFIG_X86_64 | |
5624 | " x86-tsc: TSC cycle counter\n" | |
5625 | #endif | |
cf2adec7 | 5626 | "\n timestamp_mode\t- view the mode used to timestamp events\n" |
2c1ea60b TZ |
5627 | " delta: Delta difference against a buffer-wide timestamp\n" |
5628 | " absolute: Absolute (standalone) timestamp\n" | |
22f45649 | 5629 | "\n trace_marker\t\t- Writes into this file writes into the kernel buffer\n" |
fa32e855 | 5630 | "\n trace_marker_raw\t\t- Writes into this file writes binary data into the kernel buffer\n" |
22f45649 SRRH |
5631 | " tracing_cpumask\t- Limit which CPUs to trace\n" |
5632 | " instances\t\t- Make sub-buffers with: mkdir instances/foo\n" | |
5633 | "\t\t\t Remove sub-buffer with rmdir\n" | |
5634 | " trace_options\t\t- Set format or modify how tracing happens\n" | |
b9416997 | 5635 | "\t\t\t Disable an option by prefixing 'no' to the\n" |
71485c45 | 5636 | "\t\t\t option name\n" |
939c7a4f | 5637 | " saved_cmdlines_size\t- echo command number in here to store comm-pid list\n" |
22f45649 SRRH |
5638 | #ifdef CONFIG_DYNAMIC_FTRACE |
5639 | "\n available_filter_functions - list of functions that can be filtered on\n" | |
71485c45 SRRH |
5640 | " set_ftrace_filter\t- echo function name in here to only trace these\n" |
5641 | "\t\t\t functions\n" | |
60f1d5e3 | 5642 | "\t accepts: func_full_name or glob-matching-pattern\n" |
71485c45 SRRH |
5643 | "\t modules: Can select a group via module\n" |
5644 | "\t Format: :mod:<module-name>\n" | |
5645 | "\t example: echo :mod:ext3 > set_ftrace_filter\n" | |
5646 | "\t triggers: a command to perform when function is hit\n" | |
5647 | "\t Format: <function>:<trigger>[:count]\n" | |
5648 | "\t trigger: traceon, traceoff\n" | |
5649 | "\t\t enable_event:<system>:<event>\n" | |
5650 | "\t\t disable_event:<system>:<event>\n" | |
22f45649 | 5651 | #ifdef CONFIG_STACKTRACE |
71485c45 | 5652 | "\t\t stacktrace\n" |
22f45649 SRRH |
5653 | #endif |
5654 | #ifdef CONFIG_TRACER_SNAPSHOT | |
71485c45 | 5655 | "\t\t snapshot\n" |
22f45649 | 5656 | #endif |
17a280ea SRRH |
5657 | "\t\t dump\n" |
5658 | "\t\t cpudump\n" | |
71485c45 SRRH |
5659 | "\t example: echo do_fault:traceoff > set_ftrace_filter\n" |
5660 | "\t echo do_trap:traceoff:3 > set_ftrace_filter\n" | |
5661 | "\t The first one will disable tracing every time do_fault is hit\n" | |
5662 | "\t The second will disable tracing at most 3 times when do_trap is hit\n" | |
5663 | "\t The first time do trap is hit and it disables tracing, the\n" | |
5664 | "\t counter will decrement to 2. If tracing is already disabled,\n" | |
5665 | "\t the counter will not decrement. It only decrements when the\n" | |
5666 | "\t trigger did work\n" | |
5667 | "\t To remove trigger without count:\n" | |
5668 | "\t echo '!<function>:<trigger> > set_ftrace_filter\n" | |
5669 | "\t To remove trigger with a count:\n" | |
5670 | "\t echo '!<function>:<trigger>:0 > set_ftrace_filter\n" | |
22f45649 | 5671 | " set_ftrace_notrace\t- echo function name in here to never trace.\n" |
71485c45 SRRH |
5672 | "\t accepts: func_full_name, *func_end, func_begin*, *func_middle*\n" |
5673 | "\t modules: Can select a group via module command :mod:\n" | |
5674 | "\t Does not accept triggers\n" | |
22f45649 SRRH |
5675 | #endif /* CONFIG_DYNAMIC_FTRACE */ |
5676 | #ifdef CONFIG_FUNCTION_TRACER | |
71485c45 SRRH |
5677 | " set_ftrace_pid\t- Write pid(s) to only function trace those pids\n" |
5678 | "\t\t (function)\n" | |
b3b1e6ed SRV |
5679 | " set_ftrace_notrace_pid\t- Write pid(s) to not function trace those pids\n" |
5680 | "\t\t (function)\n" | |
22f45649 SRRH |
5681 | #endif |
5682 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER | |
5683 | " set_graph_function\t- Trace the nested calls of a function (function_graph)\n" | |
d048a8c7 | 5684 | " set_graph_notrace\t- Do not trace the nested calls of a function (function_graph)\n" |
22f45649 SRRH |
5685 | " max_graph_depth\t- Trace a limited depth of nested calls (0 is unlimited)\n" |
5686 | #endif | |
5687 | #ifdef CONFIG_TRACER_SNAPSHOT | |
71485c45 SRRH |
5688 | "\n snapshot\t\t- Like 'trace' but shows the content of the static\n" |
5689 | "\t\t\t snapshot buffer. Read the contents for more\n" | |
5690 | "\t\t\t information\n" | |
22f45649 | 5691 | #endif |
991821c8 | 5692 | #ifdef CONFIG_STACK_TRACER |
22f45649 SRRH |
5693 | " stack_trace\t\t- Shows the max stack trace when active\n" |
5694 | " stack_max_size\t- Shows current max stack size that was traced\n" | |
71485c45 SRRH |
5695 | "\t\t\t Write into this file to reset the max size (trigger a\n" |
5696 | "\t\t\t new trace)\n" | |
22f45649 | 5697 | #ifdef CONFIG_DYNAMIC_FTRACE |
71485c45 SRRH |
5698 | " stack_trace_filter\t- Like set_ftrace_filter but limits what stack_trace\n" |
5699 | "\t\t\t traces\n" | |
22f45649 | 5700 | #endif |
991821c8 | 5701 | #endif /* CONFIG_STACK_TRACER */ |
5448d44c | 5702 | #ifdef CONFIG_DYNAMIC_EVENTS |
ca89bc07 | 5703 | " dynamic_events\t\t- Create/append/remove/show the generic dynamic events\n" |
5448d44c MH |
5704 | "\t\t\t Write into this file to define/undefine new trace events.\n" |
5705 | #endif | |
6b0b7551 | 5706 | #ifdef CONFIG_KPROBE_EVENTS |
ca89bc07 | 5707 | " kprobe_events\t\t- Create/append/remove/show the kernel dynamic events\n" |
86425625 MH |
5708 | "\t\t\t Write into this file to define/undefine new trace events.\n" |
5709 | #endif | |
6b0b7551 | 5710 | #ifdef CONFIG_UPROBE_EVENTS |
41af3cf5 | 5711 | " uprobe_events\t\t- Create/append/remove/show the userspace dynamic events\n" |
86425625 MH |
5712 | "\t\t\t Write into this file to define/undefine new trace events.\n" |
5713 | #endif | |
334e5519 MHG |
5714 | #if defined(CONFIG_KPROBE_EVENTS) || defined(CONFIG_UPROBE_EVENTS) || \ |
5715 | defined(CONFIG_FPROBE_EVENTS) | |
86425625 | 5716 | "\t accepts: event-definitions (one definition per line)\n" |
334e5519 | 5717 | #if defined(CONFIG_KPROBE_EVENTS) || defined(CONFIG_UPROBE_EVENTS) |
95c104c3 LY |
5718 | "\t Format: p[:[<group>/][<event>]] <place> [<args>]\n" |
5719 | "\t r[maxactive][:[<group>/][<event>]] <place> [<args>]\n" | |
334e5519 MHG |
5720 | #endif |
5721 | #ifdef CONFIG_FPROBE_EVENTS | |
5722 | "\t f[:[<group>/][<event>]] <func-name>[%return] [<args>]\n" | |
e2d0d7b2 | 5723 | "\t t[:[<group>/][<event>]] <tracepoint> [<args>]\n" |
334e5519 | 5724 | #endif |
7bbab38d MH |
5725 | #ifdef CONFIG_HIST_TRIGGERS |
5726 | "\t s:[synthetic/]<event> <field> [<field>]\n" | |
5727 | #endif | |
13392153 | 5728 | "\t e[:[<group>/][<event>]] <attached-group>.<attached-event> [<args>] [if <filter>]\n" |
95c104c3 | 5729 | "\t -:[<group>/][<event>]\n" |
6b0b7551 | 5730 | #ifdef CONFIG_KPROBE_EVENTS |
86425625 | 5731 | "\t place: [<module>:]<symbol>[+<offset>]|<memaddr>\n" |
4725cd89 | 5732 | "place (kretprobe): [<module>:]<symbol>[+<offset>]%return|<memaddr>\n" |
86425625 | 5733 | #endif |
6b0b7551 | 5734 | #ifdef CONFIG_UPROBE_EVENTS |
3dd3aae3 | 5735 | " place (uprobe): <path>:<offset>[%return][(ref_ctr_offset)]\n" |
86425625 MH |
5736 | #endif |
5737 | "\t args: <name>=fetcharg[:type]\n" | |
7491e2c4 | 5738 | "\t fetcharg: (%<register>|$<efield>), @<address>, @<symbol>[+|-<offset>],\n" |
a1303af5 | 5739 | #ifdef CONFIG_HAVE_FUNCTION_ARG_ACCESS_API |
b576e097 | 5740 | #ifdef CONFIG_PROBE_EVENTS_BTF_ARGS |
c440adfb MHG |
5741 | "\t $stack<index>, $stack, $retval, $comm, $arg<N>,\n" |
5742 | "\t <argname>[->field[->field|.field...]],\n" | |
b576e097 | 5743 | #else |
e65f7ae7 | 5744 | "\t $stack<index>, $stack, $retval, $comm, $arg<N>,\n" |
b576e097 | 5745 | #endif |
a1303af5 | 5746 | #else |
e65f7ae7 | 5747 | "\t $stack<index>, $stack, $retval, $comm,\n" |
a1303af5 | 5748 | #endif |
a42e3c4d | 5749 | "\t +|-[u]<offset>(<fetcharg>), \\imm-value, \\\"imm-string\"\n" |
8478cca1 | 5750 | "\t type: s8/16/32/64, u8/16/32/64, x8/16/32/64, char, string, symbol,\n" |
88903c46 | 5751 | "\t b<bit-width>@<bit-offset>/<container-size>, ustring,\n" |
b26a124c | 5752 | "\t symstr, <type>\\[<array-size>\\]\n" |
7bbab38d MH |
5753 | #ifdef CONFIG_HIST_TRIGGERS |
5754 | "\t field: <stype> <name>;\n" | |
5755 | "\t stype: u8/u16/u32/u64, s8/s16/s32/s64, pid_t,\n" | |
5756 | "\t [unsigned] char/int/long\n" | |
5757 | #endif | |
7491e2c4 TSV |
5758 | "\t efield: For event probes ('e' types), the field is on of the fields\n" |
5759 | "\t of the <attached-group>/<attached-event>.\n" | |
86425625 | 5760 | #endif |
26f25564 TZ |
5761 | " events/\t\t- Directory containing all trace event subsystems:\n" |
5762 | " enable\t\t- Write 0/1 to enable/disable tracing of all events\n" | |
5763 | " events/<system>/\t- Directory containing all trace events for <system>:\n" | |
71485c45 SRRH |
5764 | " enable\t\t- Write 0/1 to enable/disable tracing of all <system>\n" |
5765 | "\t\t\t events\n" | |
26f25564 | 5766 | " filter\t\t- If set, only events passing filter are traced\n" |
71485c45 SRRH |
5767 | " events/<system>/<event>/\t- Directory containing control files for\n" |
5768 | "\t\t\t <event>:\n" | |
26f25564 TZ |
5769 | " enable\t\t- Write 0/1 to enable/disable tracing of <event>\n" |
5770 | " filter\t\t- If set, only events passing filter are traced\n" | |
5771 | " trigger\t\t- If set, a command to perform when event is hit\n" | |
71485c45 SRRH |
5772 | "\t Format: <trigger>[:count][if <filter>]\n" |
5773 | "\t trigger: traceon, traceoff\n" | |
5774 | "\t enable_event:<system>:<event>\n" | |
5775 | "\t disable_event:<system>:<event>\n" | |
d0bad49b TZ |
5776 | #ifdef CONFIG_HIST_TRIGGERS |
5777 | "\t enable_hist:<system>:<event>\n" | |
5778 | "\t disable_hist:<system>:<event>\n" | |
5779 | #endif | |
26f25564 | 5780 | #ifdef CONFIG_STACKTRACE |
71485c45 | 5781 | "\t\t stacktrace\n" |
26f25564 TZ |
5782 | #endif |
5783 | #ifdef CONFIG_TRACER_SNAPSHOT | |
71485c45 | 5784 | "\t\t snapshot\n" |
7ef224d1 TZ |
5785 | #endif |
5786 | #ifdef CONFIG_HIST_TRIGGERS | |
5787 | "\t\t hist (see below)\n" | |
26f25564 | 5788 | #endif |
71485c45 SRRH |
5789 | "\t example: echo traceoff > events/block/block_unplug/trigger\n" |
5790 | "\t echo traceoff:3 > events/block/block_unplug/trigger\n" | |
5791 | "\t echo 'enable_event:kmem:kmalloc:3 if nr_rq > 1' > \\\n" | |
5792 | "\t events/block/block_unplug/trigger\n" | |
5793 | "\t The first disables tracing every time block_unplug is hit.\n" | |
5794 | "\t The second disables tracing the first 3 times block_unplug is hit.\n" | |
5795 | "\t The third enables the kmalloc event the first 3 times block_unplug\n" | |
5796 | "\t is hit and has value of greater than 1 for the 'nr_rq' event field.\n" | |
5797 | "\t Like function triggers, the counter is only decremented if it\n" | |
5798 | "\t enabled or disabled tracing.\n" | |
5799 | "\t To remove a trigger without a count:\n" | |
5800 | "\t echo '!<trigger> > <system>/<event>/trigger\n" | |
5801 | "\t To remove a trigger with a count:\n" | |
5802 | "\t echo '!<trigger>:0 > <system>/<event>/trigger\n" | |
5803 | "\t Filters can be ignored when removing a trigger.\n" | |
7ef224d1 TZ |
5804 | #ifdef CONFIG_HIST_TRIGGERS |
5805 | " hist trigger\t- If set, event hits are aggregated into a hash table\n" | |
76a3b0c8 | 5806 | "\t Format: hist:keys=<field1[,field2,...]>\n" |
6a6e5ef2 | 5807 | "\t [:<var1>=<field|var_ref|numeric_literal>[,<var2>=...]]\n" |
f2606835 | 5808 | "\t [:values=<field1[,field2,...]>]\n" |
e62347d2 | 5809 | "\t [:sort=<field1[,field2,...]>]\n" |
7ef224d1 | 5810 | "\t [:size=#entries]\n" |
e86ae9ba | 5811 | "\t [:pause][:continue][:clear]\n" |
5463bfda | 5812 | "\t [:name=histname1]\n" |
ccf47f5c | 5813 | "\t [:nohitcount]\n" |
c3e49506 | 5814 | "\t [:<handler>.<action>]\n" |
7ef224d1 | 5815 | "\t [if <filter>]\n\n" |
1e3bac71 SRV |
5816 | "\t Note, special fields can be used as well:\n" |
5817 | "\t common_timestamp - to record current timestamp\n" | |
5818 | "\t common_cpu - to record the CPU the event happened on\n" | |
5819 | "\n" | |
6a6e5ef2 KS |
5820 | "\t A hist trigger variable can be:\n" |
5821 | "\t - a reference to a field e.g. x=current_timestamp,\n" | |
5822 | "\t - a reference to another variable e.g. y=$x,\n" | |
5823 | "\t - a numeric literal: e.g. ms_per_sec=1000,\n" | |
5824 | "\t - an arithmetic expression: e.g. time_secs=current_timestamp/1000\n" | |
5825 | "\n" | |
f2b20c66 | 5826 | "\t hist trigger arithmetic expressions support addition(+), subtraction(-),\n" |
6a6e5ef2 KS |
5827 | "\t multiplication(*) and division(/) operators. An operand can be either a\n" |
5828 | "\t variable reference, field or numeric literal.\n" | |
5829 | "\n" | |
7ef224d1 | 5830 | "\t When a matching event is hit, an entry is added to a hash\n" |
f2606835 TZ |
5831 | "\t table using the key(s) and value(s) named, and the value of a\n" |
5832 | "\t sum called 'hitcount' is incremented. Keys and values\n" | |
5833 | "\t correspond to fields in the event's format description. Keys\n" | |
4b512860 | 5834 | "\t can be any field, or the special string 'common_stacktrace'.\n" |
69a0200c TZ |
5835 | "\t Compound keys consisting of up to two fields can be specified\n" |
5836 | "\t by the 'keys' keyword. Values must correspond to numeric\n" | |
5837 | "\t fields. Sort keys consisting of up to two fields can be\n" | |
5838 | "\t specified using the 'sort' keyword. The sort direction can\n" | |
5839 | "\t be modified by appending '.descending' or '.ascending' to a\n" | |
5840 | "\t sort field. The 'size' parameter can be used to specify more\n" | |
5463bfda TZ |
5841 | "\t or fewer than the default 2048 entries for the hashtable size.\n" |
5842 | "\t If a hist trigger is given a name using the 'name' parameter,\n" | |
5843 | "\t its histogram data will be shared with other triggers of the\n" | |
5844 | "\t same name, and trigger hits will update this common data.\n\n" | |
7ef224d1 | 5845 | "\t Reading the 'hist' file for the event will dump the hash\n" |
52a7f16d TZ |
5846 | "\t table in its entirety to stdout. If there are multiple hist\n" |
5847 | "\t triggers attached to an event, there will be a table for each\n" | |
5463bfda TZ |
5848 | "\t trigger in the output. The table displayed for a named\n" |
5849 | "\t trigger will be the same as any other instance having the\n" | |
5850 | "\t same name. The default format used to display a given field\n" | |
5851 | "\t can be modified by appending any of the following modifiers\n" | |
5852 | "\t to the field name, as applicable:\n\n" | |
c6afad49 TZ |
5853 | "\t .hex display a number as a hex value\n" |
5854 | "\t .sym display an address as a symbol\n" | |
6b4827ad | 5855 | "\t .sym-offset display an address as a symbol and offset\n" |
31696198 | 5856 | "\t .execname display a common_pid as a program name\n" |
860f9f6b TZ |
5857 | "\t .syscall display a syscall id as a syscall name\n" |
5858 | "\t .log2 display log2 value rather than raw number\n" | |
37036435 | 5859 | "\t .buckets=size display values in groups of size rather than raw number\n" |
abaa5258 | 5860 | "\t .usecs display a common_timestamp in microseconds\n" |
a2c54256 MHG |
5861 | "\t .percent display a number of percentage value\n" |
5862 | "\t .graph display a bar-graph of a value\n\n" | |
83e99914 TZ |
5863 | "\t The 'pause' parameter can be used to pause an existing hist\n" |
5864 | "\t trigger or to start a hist trigger but not log any events\n" | |
5865 | "\t until told to do so. 'continue' can be used to start or\n" | |
5866 | "\t restart a paused hist trigger.\n\n" | |
e86ae9ba TZ |
5867 | "\t The 'clear' parameter will clear the contents of a running\n" |
5868 | "\t hist trigger and leave its current paused/active state\n" | |
5869 | "\t unchanged.\n\n" | |
ccf47f5c MHG |
5870 | "\t The 'nohitcount' (or NOHC) parameter will suppress display of\n" |
5871 | "\t raw hitcount in the histogram.\n\n" | |
d0bad49b TZ |
5872 | "\t The enable_hist and disable_hist triggers can be used to\n" |
5873 | "\t have one event conditionally start and stop another event's\n" | |
9e5a36a3 | 5874 | "\t already-attached hist trigger. The syntax is analogous to\n" |
c3e49506 TZ |
5875 | "\t the enable_event and disable_event triggers.\n\n" |
5876 | "\t Hist trigger handlers and actions are executed whenever a\n" | |
5877 | "\t a histogram entry is added or updated. They take the form:\n\n" | |
5878 | "\t <handler>.<action>\n\n" | |
5879 | "\t The available handlers are:\n\n" | |
5880 | "\t onmatch(matching.event) - invoke on addition or update\n" | |
dff81f55 TZ |
5881 | "\t onmax(var) - invoke if var exceeds current max\n" |
5882 | "\t onchange(var) - invoke action if var changes\n\n" | |
c3e49506 | 5883 | "\t The available actions are:\n\n" |
e91eefd7 | 5884 | "\t trace(<synthetic_event>,param list) - generate synthetic event\n" |
c3e49506 | 5885 | "\t save(field,...) - save current event fields\n" |
a3785b7e | 5886 | #ifdef CONFIG_TRACER_SNAPSHOT |
1bc36bd4 TZ |
5887 | "\t snapshot() - snapshot the trace buffer\n\n" |
5888 | #endif | |
5889 | #ifdef CONFIG_SYNTH_EVENTS | |
5890 | " events/synthetic_events\t- Create/append/remove/show synthetic events\n" | |
5891 | "\t Write into this file to define/undefine new synthetic events.\n" | |
b81a3a10 | 5892 | "\t example: echo 'myevent u64 lat; char name[]; long[] stack' >> synthetic_events\n" |
a3785b7e | 5893 | #endif |
7ef224d1 | 5894 | #endif |
7bd2f24c IM |
5895 | ; |
5896 | ||
5897 | static ssize_t | |
5898 | tracing_readme_read(struct file *filp, char __user *ubuf, | |
5899 | size_t cnt, loff_t *ppos) | |
5900 | { | |
5901 | return simple_read_from_buffer(ubuf, cnt, ppos, | |
5902 | readme_msg, strlen(readme_msg)); | |
5903 | } | |
5904 | ||
5e2336a0 | 5905 | static const struct file_operations tracing_readme_fops = { |
c7078de1 IM |
5906 | .open = tracing_open_generic, |
5907 | .read = tracing_readme_read, | |
b444786f | 5908 | .llseek = generic_file_llseek, |
7bd2f24c IM |
5909 | }; |
5910 | ||
99c621d7 MS |
5911 | static void *saved_tgids_next(struct seq_file *m, void *v, loff_t *pos) |
5912 | { | |
b81b3e95 | 5913 | int pid = ++(*pos); |
99c621d7 | 5914 | |
4030a6e6 | 5915 | return trace_find_tgid_ptr(pid); |
99c621d7 MS |
5916 | } |
5917 | ||
5918 | static void *saved_tgids_start(struct seq_file *m, loff_t *pos) | |
5919 | { | |
4030a6e6 | 5920 | int pid = *pos; |
99c621d7 | 5921 | |
4030a6e6 | 5922 | return trace_find_tgid_ptr(pid); |
99c621d7 MS |
5923 | } |
5924 | ||
5925 | static void saved_tgids_stop(struct seq_file *m, void *v) | |
5926 | { | |
5927 | } | |
5928 | ||
5929 | static int saved_tgids_show(struct seq_file *m, void *v) | |
5930 | { | |
b81b3e95 PB |
5931 | int *entry = (int *)v; |
5932 | int pid = entry - tgid_map; | |
5933 | int tgid = *entry; | |
99c621d7 | 5934 | |
b81b3e95 PB |
5935 | if (tgid == 0) |
5936 | return SEQ_SKIP; | |
99c621d7 | 5937 | |
b81b3e95 | 5938 | seq_printf(m, "%d %d\n", pid, tgid); |
99c621d7 MS |
5939 | return 0; |
5940 | } | |
5941 | ||
5942 | static const struct seq_operations tracing_saved_tgids_seq_ops = { | |
5943 | .start = saved_tgids_start, | |
5944 | .stop = saved_tgids_stop, | |
5945 | .next = saved_tgids_next, | |
5946 | .show = saved_tgids_show, | |
5947 | }; | |
5948 | ||
5949 | static int tracing_saved_tgids_open(struct inode *inode, struct file *filp) | |
5950 | { | |
8530dec6 SRV |
5951 | int ret; |
5952 | ||
5953 | ret = tracing_check_open_get_tr(NULL); | |
5954 | if (ret) | |
5955 | return ret; | |
99c621d7 MS |
5956 | |
5957 | return seq_open(filp, &tracing_saved_tgids_seq_ops); | |
5958 | } | |
5959 | ||
5960 | ||
5961 | static const struct file_operations tracing_saved_tgids_fops = { | |
5962 | .open = tracing_saved_tgids_open, | |
5963 | .read = seq_read, | |
5964 | .llseek = seq_lseek, | |
5965 | .release = seq_release, | |
5966 | }; | |
5967 | ||
42584c81 YY |
5968 | static void *saved_cmdlines_next(struct seq_file *m, void *v, loff_t *pos) |
5969 | { | |
5970 | unsigned int *ptr = v; | |
69abe6a5 | 5971 | |
42584c81 YY |
5972 | if (*pos || m->count) |
5973 | ptr++; | |
69abe6a5 | 5974 | |
42584c81 | 5975 | (*pos)++; |
69abe6a5 | 5976 | |
939c7a4f YY |
5977 | for (; ptr < &savedcmd->map_cmdline_to_pid[savedcmd->cmdline_num]; |
5978 | ptr++) { | |
42584c81 YY |
5979 | if (*ptr == -1 || *ptr == NO_CMDLINE_MAP) |
5980 | continue; | |
69abe6a5 | 5981 | |
42584c81 YY |
5982 | return ptr; |
5983 | } | |
69abe6a5 | 5984 | |
42584c81 YY |
5985 | return NULL; |
5986 | } | |
5987 | ||
5988 | static void *saved_cmdlines_start(struct seq_file *m, loff_t *pos) | |
5989 | { | |
5990 | void *v; | |
5991 | loff_t l = 0; | |
69abe6a5 | 5992 | |
4c27e756 SRRH |
5993 | preempt_disable(); |
5994 | arch_spin_lock(&trace_cmdline_lock); | |
5995 | ||
939c7a4f | 5996 | v = &savedcmd->map_cmdline_to_pid[0]; |
42584c81 YY |
5997 | while (l <= *pos) { |
5998 | v = saved_cmdlines_next(m, v, &l); | |
5999 | if (!v) | |
6000 | return NULL; | |
69abe6a5 AP |
6001 | } |
6002 | ||
42584c81 YY |
6003 | return v; |
6004 | } | |
6005 | ||
6006 | static void saved_cmdlines_stop(struct seq_file *m, void *v) | |
6007 | { | |
4c27e756 SRRH |
6008 | arch_spin_unlock(&trace_cmdline_lock); |
6009 | preempt_enable(); | |
42584c81 | 6010 | } |
69abe6a5 | 6011 | |
42584c81 YY |
6012 | static int saved_cmdlines_show(struct seq_file *m, void *v) |
6013 | { | |
6014 | char buf[TASK_COMM_LEN]; | |
6015 | unsigned int *pid = v; | |
69abe6a5 | 6016 | |
4c27e756 | 6017 | __trace_find_cmdline(*pid, buf); |
42584c81 YY |
6018 | seq_printf(m, "%d %s\n", *pid, buf); |
6019 | return 0; | |
6020 | } | |
6021 | ||
6022 | static const struct seq_operations tracing_saved_cmdlines_seq_ops = { | |
6023 | .start = saved_cmdlines_start, | |
6024 | .next = saved_cmdlines_next, | |
6025 | .stop = saved_cmdlines_stop, | |
6026 | .show = saved_cmdlines_show, | |
6027 | }; | |
6028 | ||
6029 | static int tracing_saved_cmdlines_open(struct inode *inode, struct file *filp) | |
6030 | { | |
8530dec6 SRV |
6031 | int ret; |
6032 | ||
6033 | ret = tracing_check_open_get_tr(NULL); | |
6034 | if (ret) | |
6035 | return ret; | |
42584c81 YY |
6036 | |
6037 | return seq_open(filp, &tracing_saved_cmdlines_seq_ops); | |
69abe6a5 AP |
6038 | } |
6039 | ||
6040 | static const struct file_operations tracing_saved_cmdlines_fops = { | |
42584c81 YY |
6041 | .open = tracing_saved_cmdlines_open, |
6042 | .read = seq_read, | |
6043 | .llseek = seq_lseek, | |
6044 | .release = seq_release, | |
69abe6a5 AP |
6045 | }; |
6046 | ||
939c7a4f YY |
6047 | static ssize_t |
6048 | tracing_saved_cmdlines_size_read(struct file *filp, char __user *ubuf, | |
6049 | size_t cnt, loff_t *ppos) | |
6050 | { | |
6051 | char buf[64]; | |
6052 | int r; | |
6053 | ||
c0a581d7 | 6054 | preempt_disable(); |
939c7a4f | 6055 | arch_spin_lock(&trace_cmdline_lock); |
a6af8fbf | 6056 | r = scnprintf(buf, sizeof(buf), "%u\n", savedcmd->cmdline_num); |
939c7a4f | 6057 | arch_spin_unlock(&trace_cmdline_lock); |
c0a581d7 | 6058 | preempt_enable(); |
939c7a4f YY |
6059 | |
6060 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
6061 | } | |
6062 | ||
6063 | static void free_saved_cmdlines_buffer(struct saved_cmdlines_buffer *s) | |
6064 | { | |
6065 | kfree(s->saved_cmdlines); | |
6066 | kfree(s->map_cmdline_to_pid); | |
6067 | kfree(s); | |
6068 | } | |
6069 | ||
6070 | static int tracing_resize_saved_cmdlines(unsigned int val) | |
6071 | { | |
6072 | struct saved_cmdlines_buffer *s, *savedcmd_temp; | |
6073 | ||
a6af8fbf | 6074 | s = kmalloc(sizeof(*s), GFP_KERNEL); |
939c7a4f YY |
6075 | if (!s) |
6076 | return -ENOMEM; | |
6077 | ||
6078 | if (allocate_cmdlines_buffer(val, s) < 0) { | |
6079 | kfree(s); | |
6080 | return -ENOMEM; | |
6081 | } | |
6082 | ||
c0a581d7 | 6083 | preempt_disable(); |
939c7a4f YY |
6084 | arch_spin_lock(&trace_cmdline_lock); |
6085 | savedcmd_temp = savedcmd; | |
6086 | savedcmd = s; | |
6087 | arch_spin_unlock(&trace_cmdline_lock); | |
c0a581d7 | 6088 | preempt_enable(); |
939c7a4f YY |
6089 | free_saved_cmdlines_buffer(savedcmd_temp); |
6090 | ||
6091 | return 0; | |
6092 | } | |
6093 | ||
6094 | static ssize_t | |
6095 | tracing_saved_cmdlines_size_write(struct file *filp, const char __user *ubuf, | |
6096 | size_t cnt, loff_t *ppos) | |
6097 | { | |
6098 | unsigned long val; | |
6099 | int ret; | |
6100 | ||
6101 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); | |
6102 | if (ret) | |
6103 | return ret; | |
6104 | ||
6105 | /* must have at least 1 entry or less than PID_MAX_DEFAULT */ | |
6106 | if (!val || val > PID_MAX_DEFAULT) | |
6107 | return -EINVAL; | |
6108 | ||
6109 | ret = tracing_resize_saved_cmdlines((unsigned int)val); | |
6110 | if (ret < 0) | |
6111 | return ret; | |
6112 | ||
6113 | *ppos += cnt; | |
6114 | ||
6115 | return cnt; | |
6116 | } | |
6117 | ||
6118 | static const struct file_operations tracing_saved_cmdlines_size_fops = { | |
6119 | .open = tracing_open_generic, | |
6120 | .read = tracing_saved_cmdlines_size_read, | |
6121 | .write = tracing_saved_cmdlines_size_write, | |
6122 | }; | |
6123 | ||
681bec03 | 6124 | #ifdef CONFIG_TRACE_EVAL_MAP_FILE |
23bf8cb8 | 6125 | static union trace_eval_map_item * |
f57a4143 | 6126 | update_eval_map(union trace_eval_map_item *ptr) |
9828413d | 6127 | { |
00f4b652 | 6128 | if (!ptr->map.eval_string) { |
9828413d SRRH |
6129 | if (ptr->tail.next) { |
6130 | ptr = ptr->tail.next; | |
6131 | /* Set ptr to the next real item (skip head) */ | |
6132 | ptr++; | |
6133 | } else | |
6134 | return NULL; | |
6135 | } | |
6136 | return ptr; | |
6137 | } | |
6138 | ||
f57a4143 | 6139 | static void *eval_map_next(struct seq_file *m, void *v, loff_t *pos) |
9828413d | 6140 | { |
23bf8cb8 | 6141 | union trace_eval_map_item *ptr = v; |
9828413d SRRH |
6142 | |
6143 | /* | |
6144 | * Paranoid! If ptr points to end, we don't want to increment past it. | |
6145 | * This really should never happen. | |
6146 | */ | |
039958a5 | 6147 | (*pos)++; |
f57a4143 | 6148 | ptr = update_eval_map(ptr); |
9828413d SRRH |
6149 | if (WARN_ON_ONCE(!ptr)) |
6150 | return NULL; | |
6151 | ||
6152 | ptr++; | |
f57a4143 | 6153 | ptr = update_eval_map(ptr); |
9828413d SRRH |
6154 | |
6155 | return ptr; | |
6156 | } | |
6157 | ||
f57a4143 | 6158 | static void *eval_map_start(struct seq_file *m, loff_t *pos) |
9828413d | 6159 | { |
23bf8cb8 | 6160 | union trace_eval_map_item *v; |
9828413d SRRH |
6161 | loff_t l = 0; |
6162 | ||
1793ed93 | 6163 | mutex_lock(&trace_eval_mutex); |
9828413d | 6164 | |
23bf8cb8 | 6165 | v = trace_eval_maps; |
9828413d SRRH |
6166 | if (v) |
6167 | v++; | |
6168 | ||
6169 | while (v && l < *pos) { | |
f57a4143 | 6170 | v = eval_map_next(m, v, &l); |
9828413d SRRH |
6171 | } |
6172 | ||
6173 | return v; | |
6174 | } | |
6175 | ||
f57a4143 | 6176 | static void eval_map_stop(struct seq_file *m, void *v) |
9828413d | 6177 | { |
1793ed93 | 6178 | mutex_unlock(&trace_eval_mutex); |
9828413d SRRH |
6179 | } |
6180 | ||
f57a4143 | 6181 | static int eval_map_show(struct seq_file *m, void *v) |
9828413d | 6182 | { |
23bf8cb8 | 6183 | union trace_eval_map_item *ptr = v; |
9828413d SRRH |
6184 | |
6185 | seq_printf(m, "%s %ld (%s)\n", | |
00f4b652 | 6186 | ptr->map.eval_string, ptr->map.eval_value, |
9828413d SRRH |
6187 | ptr->map.system); |
6188 | ||
6189 | return 0; | |
6190 | } | |
6191 | ||
f57a4143 JL |
6192 | static const struct seq_operations tracing_eval_map_seq_ops = { |
6193 | .start = eval_map_start, | |
6194 | .next = eval_map_next, | |
6195 | .stop = eval_map_stop, | |
6196 | .show = eval_map_show, | |
9828413d SRRH |
6197 | }; |
6198 | ||
f57a4143 | 6199 | static int tracing_eval_map_open(struct inode *inode, struct file *filp) |
9828413d | 6200 | { |
8530dec6 SRV |
6201 | int ret; |
6202 | ||
6203 | ret = tracing_check_open_get_tr(NULL); | |
6204 | if (ret) | |
6205 | return ret; | |
9828413d | 6206 | |
f57a4143 | 6207 | return seq_open(filp, &tracing_eval_map_seq_ops); |
9828413d SRRH |
6208 | } |
6209 | ||
f57a4143 JL |
6210 | static const struct file_operations tracing_eval_map_fops = { |
6211 | .open = tracing_eval_map_open, | |
9828413d SRRH |
6212 | .read = seq_read, |
6213 | .llseek = seq_lseek, | |
6214 | .release = seq_release, | |
6215 | }; | |
6216 | ||
23bf8cb8 | 6217 | static inline union trace_eval_map_item * |
5f60b351 | 6218 | trace_eval_jmp_to_tail(union trace_eval_map_item *ptr) |
9828413d SRRH |
6219 | { |
6220 | /* Return tail of array given the head */ | |
6221 | return ptr + ptr->head.length + 1; | |
6222 | } | |
6223 | ||
6224 | static void | |
f57a4143 | 6225 | trace_insert_eval_map_file(struct module *mod, struct trace_eval_map **start, |
9828413d SRRH |
6226 | int len) |
6227 | { | |
00f4b652 JL |
6228 | struct trace_eval_map **stop; |
6229 | struct trace_eval_map **map; | |
23bf8cb8 JL |
6230 | union trace_eval_map_item *map_array; |
6231 | union trace_eval_map_item *ptr; | |
9828413d SRRH |
6232 | |
6233 | stop = start + len; | |
6234 | ||
6235 | /* | |
23bf8cb8 | 6236 | * The trace_eval_maps contains the map plus a head and tail item, |
9828413d SRRH |
6237 | * where the head holds the module and length of array, and the |
6238 | * tail holds a pointer to the next list. | |
6239 | */ | |
6da2ec56 | 6240 | map_array = kmalloc_array(len + 2, sizeof(*map_array), GFP_KERNEL); |
9828413d | 6241 | if (!map_array) { |
f57a4143 | 6242 | pr_warn("Unable to allocate trace eval mapping\n"); |
9828413d SRRH |
6243 | return; |
6244 | } | |
6245 | ||
1793ed93 | 6246 | mutex_lock(&trace_eval_mutex); |
9828413d | 6247 | |
23bf8cb8 JL |
6248 | if (!trace_eval_maps) |
6249 | trace_eval_maps = map_array; | |
9828413d | 6250 | else { |
23bf8cb8 | 6251 | ptr = trace_eval_maps; |
9828413d | 6252 | for (;;) { |
5f60b351 | 6253 | ptr = trace_eval_jmp_to_tail(ptr); |
9828413d SRRH |
6254 | if (!ptr->tail.next) |
6255 | break; | |
6256 | ptr = ptr->tail.next; | |
6257 | ||
6258 | } | |
6259 | ptr->tail.next = map_array; | |
6260 | } | |
6261 | map_array->head.mod = mod; | |
6262 | map_array->head.length = len; | |
6263 | map_array++; | |
6264 | ||
6265 | for (map = start; (unsigned long)map < (unsigned long)stop; map++) { | |
6266 | map_array->map = **map; | |
6267 | map_array++; | |
6268 | } | |
6269 | memset(map_array, 0, sizeof(*map_array)); | |
6270 | ||
1793ed93 | 6271 | mutex_unlock(&trace_eval_mutex); |
9828413d SRRH |
6272 | } |
6273 | ||
f57a4143 | 6274 | static void trace_create_eval_file(struct dentry *d_tracer) |
9828413d | 6275 | { |
21ccc9cd | 6276 | trace_create_file("eval_map", TRACE_MODE_READ, d_tracer, |
f57a4143 | 6277 | NULL, &tracing_eval_map_fops); |
9828413d SRRH |
6278 | } |
6279 | ||
681bec03 | 6280 | #else /* CONFIG_TRACE_EVAL_MAP_FILE */ |
f57a4143 JL |
6281 | static inline void trace_create_eval_file(struct dentry *d_tracer) { } |
6282 | static inline void trace_insert_eval_map_file(struct module *mod, | |
00f4b652 | 6283 | struct trace_eval_map **start, int len) { } |
681bec03 | 6284 | #endif /* !CONFIG_TRACE_EVAL_MAP_FILE */ |
9828413d | 6285 | |
f57a4143 | 6286 | static void trace_insert_eval_map(struct module *mod, |
00f4b652 | 6287 | struct trace_eval_map **start, int len) |
0c564a53 | 6288 | { |
00f4b652 | 6289 | struct trace_eval_map **map; |
0c564a53 SRRH |
6290 | |
6291 | if (len <= 0) | |
6292 | return; | |
6293 | ||
6294 | map = start; | |
6295 | ||
f57a4143 | 6296 | trace_event_eval_update(map, len); |
9828413d | 6297 | |
f57a4143 | 6298 | trace_insert_eval_map_file(mod, start, len); |
0c564a53 SRRH |
6299 | } |
6300 | ||
bc0c38d1 SR |
6301 | static ssize_t |
6302 | tracing_set_trace_read(struct file *filp, char __user *ubuf, | |
6303 | size_t cnt, loff_t *ppos) | |
6304 | { | |
2b6080f2 | 6305 | struct trace_array *tr = filp->private_data; |
ee6c2c1b | 6306 | char buf[MAX_TRACER_SIZE+2]; |
bc0c38d1 SR |
6307 | int r; |
6308 | ||
6309 | mutex_lock(&trace_types_lock); | |
2b6080f2 | 6310 | r = sprintf(buf, "%s\n", tr->current_trace->name); |
bc0c38d1 SR |
6311 | mutex_unlock(&trace_types_lock); |
6312 | ||
4bf39a94 | 6313 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
6314 | } |
6315 | ||
b6f11df2 ACM |
6316 | int tracer_init(struct tracer *t, struct trace_array *tr) |
6317 | { | |
1c5eb448 | 6318 | tracing_reset_online_cpus(&tr->array_buffer); |
b6f11df2 ACM |
6319 | return t->init(tr); |
6320 | } | |
6321 | ||
1c5eb448 | 6322 | static void set_buffer_entries(struct array_buffer *buf, unsigned long val) |
438ced17 VN |
6323 | { |
6324 | int cpu; | |
737223fb | 6325 | |
438ced17 | 6326 | for_each_tracing_cpu(cpu) |
12883efb | 6327 | per_cpu_ptr(buf->data, cpu)->entries = val; |
438ced17 VN |
6328 | } |
6329 | ||
6d98a0f2 ZY |
6330 | static void update_buffer_entries(struct array_buffer *buf, int cpu) |
6331 | { | |
6332 | if (cpu == RING_BUFFER_ALL_CPUS) { | |
6333 | set_buffer_entries(buf, ring_buffer_size(buf->buffer, 0)); | |
6334 | } else { | |
6335 | per_cpu_ptr(buf->data, cpu)->entries = ring_buffer_size(buf->buffer, cpu); | |
6336 | } | |
6337 | } | |
6338 | ||
12883efb | 6339 | #ifdef CONFIG_TRACER_MAX_TRACE |
d60da506 | 6340 | /* resize @tr's buffer to the size of @size_tr's entries */ |
1c5eb448 SRV |
6341 | static int resize_buffer_duplicate_size(struct array_buffer *trace_buf, |
6342 | struct array_buffer *size_buf, int cpu_id) | |
d60da506 HT |
6343 | { |
6344 | int cpu, ret = 0; | |
6345 | ||
6346 | if (cpu_id == RING_BUFFER_ALL_CPUS) { | |
6347 | for_each_tracing_cpu(cpu) { | |
12883efb SRRH |
6348 | ret = ring_buffer_resize(trace_buf->buffer, |
6349 | per_cpu_ptr(size_buf->data, cpu)->entries, cpu); | |
d60da506 HT |
6350 | if (ret < 0) |
6351 | break; | |
12883efb SRRH |
6352 | per_cpu_ptr(trace_buf->data, cpu)->entries = |
6353 | per_cpu_ptr(size_buf->data, cpu)->entries; | |
d60da506 HT |
6354 | } |
6355 | } else { | |
12883efb SRRH |
6356 | ret = ring_buffer_resize(trace_buf->buffer, |
6357 | per_cpu_ptr(size_buf->data, cpu_id)->entries, cpu_id); | |
d60da506 | 6358 | if (ret == 0) |
12883efb SRRH |
6359 | per_cpu_ptr(trace_buf->data, cpu_id)->entries = |
6360 | per_cpu_ptr(size_buf->data, cpu_id)->entries; | |
d60da506 HT |
6361 | } |
6362 | ||
6363 | return ret; | |
6364 | } | |
12883efb | 6365 | #endif /* CONFIG_TRACER_MAX_TRACE */ |
d60da506 | 6366 | |
2b6080f2 SR |
6367 | static int __tracing_resize_ring_buffer(struct trace_array *tr, |
6368 | unsigned long size, int cpu) | |
73c5162a SR |
6369 | { |
6370 | int ret; | |
6371 | ||
6372 | /* | |
6373 | * If kernel or user changes the size of the ring buffer | |
a123c52b SR |
6374 | * we use the size that was given, and we can forget about |
6375 | * expanding it later. | |
73c5162a | 6376 | */ |
55034cd6 | 6377 | ring_buffer_expanded = true; |
73c5162a | 6378 | |
b382ede6 | 6379 | /* May be called before buffers are initialized */ |
1c5eb448 | 6380 | if (!tr->array_buffer.buffer) |
b382ede6 SR |
6381 | return 0; |
6382 | ||
1c5eb448 | 6383 | ret = ring_buffer_resize(tr->array_buffer.buffer, size, cpu); |
73c5162a SR |
6384 | if (ret < 0) |
6385 | return ret; | |
6386 | ||
12883efb | 6387 | #ifdef CONFIG_TRACER_MAX_TRACE |
2b6080f2 SR |
6388 | if (!(tr->flags & TRACE_ARRAY_FL_GLOBAL) || |
6389 | !tr->current_trace->use_max_tr) | |
ef710e10 KM |
6390 | goto out; |
6391 | ||
12883efb | 6392 | ret = ring_buffer_resize(tr->max_buffer.buffer, size, cpu); |
73c5162a | 6393 | if (ret < 0) { |
1c5eb448 SRV |
6394 | int r = resize_buffer_duplicate_size(&tr->array_buffer, |
6395 | &tr->array_buffer, cpu); | |
73c5162a | 6396 | if (r < 0) { |
a123c52b SR |
6397 | /* |
6398 | * AARGH! We are left with different | |
6399 | * size max buffer!!!! | |
6400 | * The max buffer is our "snapshot" buffer. | |
6401 | * When a tracer needs a snapshot (one of the | |
6402 | * latency tracers), it swaps the max buffer | |
6403 | * with the saved snap shot. We succeeded to | |
6404 | * update the size of the main buffer, but failed to | |
6405 | * update the size of the max buffer. But when we tried | |
6406 | * to reset the main buffer to the original size, we | |
6407 | * failed there too. This is very unlikely to | |
6408 | * happen, but if it does, warn and kill all | |
6409 | * tracing. | |
6410 | */ | |
73c5162a SR |
6411 | WARN_ON(1); |
6412 | tracing_disabled = 1; | |
6413 | } | |
6414 | return ret; | |
6415 | } | |
6416 | ||
6d98a0f2 | 6417 | update_buffer_entries(&tr->max_buffer, cpu); |
438ced17 | 6418 | |
ef710e10 | 6419 | out: |
12883efb SRRH |
6420 | #endif /* CONFIG_TRACER_MAX_TRACE */ |
6421 | ||
6d98a0f2 | 6422 | update_buffer_entries(&tr->array_buffer, cpu); |
73c5162a SR |
6423 | |
6424 | return ret; | |
6425 | } | |
6426 | ||
9c5b9d3d MH |
6427 | ssize_t tracing_resize_ring_buffer(struct trace_array *tr, |
6428 | unsigned long size, int cpu_id) | |
4f271a2a | 6429 | { |
08b0c9b4 | 6430 | int ret; |
4f271a2a VN |
6431 | |
6432 | mutex_lock(&trace_types_lock); | |
6433 | ||
438ced17 VN |
6434 | if (cpu_id != RING_BUFFER_ALL_CPUS) { |
6435 | /* make sure, this cpu is enabled in the mask */ | |
6436 | if (!cpumask_test_cpu(cpu_id, tracing_buffer_mask)) { | |
6437 | ret = -EINVAL; | |
6438 | goto out; | |
6439 | } | |
6440 | } | |
4f271a2a | 6441 | |
2b6080f2 | 6442 | ret = __tracing_resize_ring_buffer(tr, size, cpu_id); |
4f271a2a VN |
6443 | if (ret < 0) |
6444 | ret = -ENOMEM; | |
6445 | ||
438ced17 | 6446 | out: |
4f271a2a VN |
6447 | mutex_unlock(&trace_types_lock); |
6448 | ||
6449 | return ret; | |
6450 | } | |
6451 | ||
ef710e10 | 6452 | |
1852fcce SR |
6453 | /** |
6454 | * tracing_update_buffers - used by tracing facility to expand ring buffers | |
6455 | * | |
6456 | * To save on memory when the tracing is never used on a system with it | |
6457 | * configured in. The ring buffers are set to a minimum size. But once | |
6458 | * a user starts to use the tracing facility, then they need to grow | |
6459 | * to their default size. | |
6460 | * | |
6461 | * This function is to be called when a tracer is about to be used. | |
6462 | */ | |
6463 | int tracing_update_buffers(void) | |
6464 | { | |
6465 | int ret = 0; | |
6466 | ||
1027fcb2 | 6467 | mutex_lock(&trace_types_lock); |
1852fcce | 6468 | if (!ring_buffer_expanded) |
2b6080f2 | 6469 | ret = __tracing_resize_ring_buffer(&global_trace, trace_buf_size, |
438ced17 | 6470 | RING_BUFFER_ALL_CPUS); |
1027fcb2 | 6471 | mutex_unlock(&trace_types_lock); |
1852fcce SR |
6472 | |
6473 | return ret; | |
6474 | } | |
6475 | ||
577b785f SR |
6476 | struct trace_option_dentry; |
6477 | ||
37aea98b | 6478 | static void |
2b6080f2 | 6479 | create_trace_option_files(struct trace_array *tr, struct tracer *tracer); |
577b785f | 6480 | |
6b450d25 SRRH |
6481 | /* |
6482 | * Used to clear out the tracer before deletion of an instance. | |
6483 | * Must have trace_types_lock held. | |
6484 | */ | |
6485 | static void tracing_set_nop(struct trace_array *tr) | |
6486 | { | |
6487 | if (tr->current_trace == &nop_trace) | |
6488 | return; | |
6489 | ||
50512ab5 | 6490 | tr->current_trace->enabled--; |
6b450d25 SRRH |
6491 | |
6492 | if (tr->current_trace->reset) | |
6493 | tr->current_trace->reset(tr); | |
6494 | ||
6495 | tr->current_trace = &nop_trace; | |
6496 | } | |
6497 | ||
ef9188bc MPT |
6498 | static bool tracer_options_updated; |
6499 | ||
41d9c0be | 6500 | static void add_tracer_options(struct trace_array *tr, struct tracer *t) |
bc0c38d1 | 6501 | { |
09d23a1d SRRH |
6502 | /* Only enable if the directory has been created already. */ |
6503 | if (!tr->dir) | |
6504 | return; | |
6505 | ||
ef9188bc MPT |
6506 | /* Only create trace option files after update_tracer_options finish */ |
6507 | if (!tracer_options_updated) | |
6508 | return; | |
6509 | ||
37aea98b | 6510 | create_trace_option_files(tr, t); |
09d23a1d SRRH |
6511 | } |
6512 | ||
9c5b9d3d | 6513 | int tracing_set_tracer(struct trace_array *tr, const char *buf) |
09d23a1d | 6514 | { |
bc0c38d1 | 6515 | struct tracer *t; |
12883efb | 6516 | #ifdef CONFIG_TRACER_MAX_TRACE |
34600f0e | 6517 | bool had_max_tr; |
12883efb | 6518 | #endif |
d9e54076 | 6519 | int ret = 0; |
bc0c38d1 | 6520 | |
1027fcb2 SR |
6521 | mutex_lock(&trace_types_lock); |
6522 | ||
73c5162a | 6523 | if (!ring_buffer_expanded) { |
2b6080f2 | 6524 | ret = __tracing_resize_ring_buffer(tr, trace_buf_size, |
438ced17 | 6525 | RING_BUFFER_ALL_CPUS); |
73c5162a | 6526 | if (ret < 0) |
59f586db | 6527 | goto out; |
73c5162a SR |
6528 | ret = 0; |
6529 | } | |
6530 | ||
bc0c38d1 SR |
6531 | for (t = trace_types; t; t = t->next) { |
6532 | if (strcmp(t->name, buf) == 0) | |
6533 | break; | |
6534 | } | |
c2931e05 FW |
6535 | if (!t) { |
6536 | ret = -EINVAL; | |
6537 | goto out; | |
6538 | } | |
2b6080f2 | 6539 | if (t == tr->current_trace) |
bc0c38d1 SR |
6540 | goto out; |
6541 | ||
a35873a0 TZ |
6542 | #ifdef CONFIG_TRACER_SNAPSHOT |
6543 | if (t->use_max_tr) { | |
c0a581d7 | 6544 | local_irq_disable(); |
a35873a0 TZ |
6545 | arch_spin_lock(&tr->max_lock); |
6546 | if (tr->cond_snapshot) | |
6547 | ret = -EBUSY; | |
6548 | arch_spin_unlock(&tr->max_lock); | |
c0a581d7 | 6549 | local_irq_enable(); |
a35873a0 TZ |
6550 | if (ret) |
6551 | goto out; | |
6552 | } | |
6553 | #endif | |
c7b3ae0b ZSZ |
6554 | /* Some tracers won't work on kernel command line */ |
6555 | if (system_state < SYSTEM_RUNNING && t->noboot) { | |
6556 | pr_warn("Tracer '%s' is not allowed on command line, ignored\n", | |
6557 | t->name); | |
6558 | goto out; | |
6559 | } | |
6560 | ||
607e2ea1 SRRH |
6561 | /* Some tracers are only allowed for the top level buffer */ |
6562 | if (!trace_ok_for_array(t, tr)) { | |
6563 | ret = -EINVAL; | |
6564 | goto out; | |
6565 | } | |
6566 | ||
cf6ab6d9 | 6567 | /* If trace pipe files are being read, we can't change the tracer */ |
7ef282e0 | 6568 | if (tr->trace_ref) { |
cf6ab6d9 SRRH |
6569 | ret = -EBUSY; |
6570 | goto out; | |
6571 | } | |
6572 | ||
9f029e83 | 6573 | trace_branch_disable(); |
613f04a0 | 6574 | |
50512ab5 | 6575 | tr->current_trace->enabled--; |
613f04a0 | 6576 | |
2b6080f2 SR |
6577 | if (tr->current_trace->reset) |
6578 | tr->current_trace->reset(tr); | |
34600f0e | 6579 | |
a541a955 SRG |
6580 | #ifdef CONFIG_TRACER_MAX_TRACE |
6581 | had_max_tr = tr->current_trace->use_max_tr; | |
6582 | ||
74401729 | 6583 | /* Current trace needs to be nop_trace before synchronize_rcu */ |
2b6080f2 | 6584 | tr->current_trace = &nop_trace; |
34600f0e SR |
6585 | |
6586 | if (had_max_tr && !t->use_max_tr) { | |
6587 | /* | |
6588 | * We need to make sure that the update_max_tr sees that | |
6589 | * current_trace changed to nop_trace to keep it from | |
6590 | * swapping the buffers after we resize it. | |
6591 | * The update_max_tr is called from interrupts disabled | |
6592 | * so a synchronized_sched() is sufficient. | |
6593 | */ | |
74401729 | 6594 | synchronize_rcu(); |
3209cff4 | 6595 | free_snapshot(tr); |
ef710e10 | 6596 | } |
12883efb | 6597 | |
a541a955 | 6598 | if (t->use_max_tr && !tr->allocated_snapshot) { |
2824f503 | 6599 | ret = tracing_alloc_snapshot_instance(tr); |
d60da506 HT |
6600 | if (ret < 0) |
6601 | goto out; | |
ef710e10 | 6602 | } |
a541a955 SRG |
6603 | #else |
6604 | tr->current_trace = &nop_trace; | |
12883efb | 6605 | #endif |
577b785f | 6606 | |
1c80025a | 6607 | if (t->init) { |
b6f11df2 | 6608 | ret = tracer_init(t, tr); |
1c80025a FW |
6609 | if (ret) |
6610 | goto out; | |
6611 | } | |
bc0c38d1 | 6612 | |
2b6080f2 | 6613 | tr->current_trace = t; |
50512ab5 | 6614 | tr->current_trace->enabled++; |
9f029e83 | 6615 | trace_branch_enable(tr); |
bc0c38d1 SR |
6616 | out: |
6617 | mutex_unlock(&trace_types_lock); | |
6618 | ||
d9e54076 PZ |
6619 | return ret; |
6620 | } | |
6621 | ||
6622 | static ssize_t | |
6623 | tracing_set_trace_write(struct file *filp, const char __user *ubuf, | |
6624 | size_t cnt, loff_t *ppos) | |
6625 | { | |
607e2ea1 | 6626 | struct trace_array *tr = filp->private_data; |
ee6c2c1b | 6627 | char buf[MAX_TRACER_SIZE+1]; |
cb24693d | 6628 | char *name; |
d9e54076 | 6629 | size_t ret; |
e6e7a65a FW |
6630 | int err; |
6631 | ||
6632 | ret = cnt; | |
d9e54076 | 6633 | |
ee6c2c1b LZ |
6634 | if (cnt > MAX_TRACER_SIZE) |
6635 | cnt = MAX_TRACER_SIZE; | |
d9e54076 | 6636 | |
4afe6495 | 6637 | if (copy_from_user(buf, ubuf, cnt)) |
d9e54076 PZ |
6638 | return -EFAULT; |
6639 | ||
6640 | buf[cnt] = 0; | |
6641 | ||
cb24693d | 6642 | name = strim(buf); |
d9e54076 | 6643 | |
cb24693d | 6644 | err = tracing_set_tracer(tr, name); |
e6e7a65a FW |
6645 | if (err) |
6646 | return err; | |
d9e54076 | 6647 | |
cf8517cf | 6648 | *ppos += ret; |
bc0c38d1 | 6649 | |
c2931e05 | 6650 | return ret; |
bc0c38d1 SR |
6651 | } |
6652 | ||
6653 | static ssize_t | |
6508fa76 SF |
6654 | tracing_nsecs_read(unsigned long *ptr, char __user *ubuf, |
6655 | size_t cnt, loff_t *ppos) | |
bc0c38d1 | 6656 | { |
bc0c38d1 SR |
6657 | char buf[64]; |
6658 | int r; | |
6659 | ||
cffae437 | 6660 | r = snprintf(buf, sizeof(buf), "%ld\n", |
bc0c38d1 | 6661 | *ptr == (unsigned long)-1 ? -1 : nsecs_to_usecs(*ptr)); |
cffae437 SR |
6662 | if (r > sizeof(buf)) |
6663 | r = sizeof(buf); | |
4bf39a94 | 6664 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
6665 | } |
6666 | ||
6667 | static ssize_t | |
6508fa76 SF |
6668 | tracing_nsecs_write(unsigned long *ptr, const char __user *ubuf, |
6669 | size_t cnt, loff_t *ppos) | |
bc0c38d1 | 6670 | { |
5e39841c | 6671 | unsigned long val; |
c6caeeb1 | 6672 | int ret; |
bc0c38d1 | 6673 | |
22fe9b54 PH |
6674 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
6675 | if (ret) | |
c6caeeb1 | 6676 | return ret; |
bc0c38d1 SR |
6677 | |
6678 | *ptr = val * 1000; | |
6679 | ||
6680 | return cnt; | |
6681 | } | |
6682 | ||
6508fa76 SF |
6683 | static ssize_t |
6684 | tracing_thresh_read(struct file *filp, char __user *ubuf, | |
6685 | size_t cnt, loff_t *ppos) | |
6686 | { | |
6687 | return tracing_nsecs_read(&tracing_thresh, ubuf, cnt, ppos); | |
6688 | } | |
6689 | ||
6690 | static ssize_t | |
6691 | tracing_thresh_write(struct file *filp, const char __user *ubuf, | |
6692 | size_t cnt, loff_t *ppos) | |
6693 | { | |
6694 | struct trace_array *tr = filp->private_data; | |
6695 | int ret; | |
6696 | ||
6697 | mutex_lock(&trace_types_lock); | |
6698 | ret = tracing_nsecs_write(&tracing_thresh, ubuf, cnt, ppos); | |
6699 | if (ret < 0) | |
6700 | goto out; | |
6701 | ||
6702 | if (tr->current_trace->update_thresh) { | |
6703 | ret = tr->current_trace->update_thresh(tr); | |
6704 | if (ret < 0) | |
6705 | goto out; | |
6706 | } | |
6707 | ||
6708 | ret = cnt; | |
6709 | out: | |
6710 | mutex_unlock(&trace_types_lock); | |
6711 | ||
6712 | return ret; | |
6713 | } | |
6714 | ||
e25e43a4 | 6715 | #ifdef CONFIG_TRACER_MAX_TRACE |
e428abbb | 6716 | |
6508fa76 SF |
6717 | static ssize_t |
6718 | tracing_max_lat_read(struct file *filp, char __user *ubuf, | |
6719 | size_t cnt, loff_t *ppos) | |
6720 | { | |
7d660c9b SRG |
6721 | struct trace_array *tr = filp->private_data; |
6722 | ||
6723 | return tracing_nsecs_read(&tr->max_latency, ubuf, cnt, ppos); | |
6508fa76 SF |
6724 | } |
6725 | ||
6726 | static ssize_t | |
6727 | tracing_max_lat_write(struct file *filp, const char __user *ubuf, | |
6728 | size_t cnt, loff_t *ppos) | |
6729 | { | |
7d660c9b SRG |
6730 | struct trace_array *tr = filp->private_data; |
6731 | ||
6732 | return tracing_nsecs_write(&tr->max_latency, ubuf, cnt, ppos); | |
6508fa76 SF |
6733 | } |
6734 | ||
e428abbb CG |
6735 | #endif |
6736 | ||
c2489bb7 ZY |
6737 | static int open_pipe_on_cpu(struct trace_array *tr, int cpu) |
6738 | { | |
6739 | if (cpu == RING_BUFFER_ALL_CPUS) { | |
6740 | if (cpumask_empty(tr->pipe_cpumask)) { | |
6741 | cpumask_setall(tr->pipe_cpumask); | |
6742 | return 0; | |
6743 | } | |
6744 | } else if (!cpumask_test_cpu(cpu, tr->pipe_cpumask)) { | |
6745 | cpumask_set_cpu(cpu, tr->pipe_cpumask); | |
6746 | return 0; | |
6747 | } | |
6748 | return -EBUSY; | |
6749 | } | |
6750 | ||
6751 | static void close_pipe_on_cpu(struct trace_array *tr, int cpu) | |
6752 | { | |
6753 | if (cpu == RING_BUFFER_ALL_CPUS) { | |
6754 | WARN_ON(!cpumask_full(tr->pipe_cpumask)); | |
6755 | cpumask_clear(tr->pipe_cpumask); | |
6756 | } else { | |
6757 | WARN_ON(!cpumask_test_cpu(cpu, tr->pipe_cpumask)); | |
6758 | cpumask_clear_cpu(cpu, tr->pipe_cpumask); | |
6759 | } | |
6760 | } | |
6761 | ||
b3806b43 SR |
6762 | static int tracing_open_pipe(struct inode *inode, struct file *filp) |
6763 | { | |
15544209 | 6764 | struct trace_array *tr = inode->i_private; |
b3806b43 | 6765 | struct trace_iterator *iter; |
c2489bb7 | 6766 | int cpu; |
8530dec6 | 6767 | int ret; |
b3806b43 | 6768 | |
8530dec6 SRV |
6769 | ret = tracing_check_open_get_tr(tr); |
6770 | if (ret) | |
6771 | return ret; | |
7b85af63 | 6772 | |
b04cc6b1 | 6773 | mutex_lock(&trace_types_lock); |
c2489bb7 ZY |
6774 | cpu = tracing_get_cpu(inode); |
6775 | ret = open_pipe_on_cpu(tr, cpu); | |
6776 | if (ret) | |
6777 | goto fail_pipe_on_cpu; | |
b04cc6b1 | 6778 | |
b3806b43 SR |
6779 | /* create a buffer to store the information to pass to userspace */ |
6780 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); | |
b04cc6b1 FW |
6781 | if (!iter) { |
6782 | ret = -ENOMEM; | |
c2489bb7 | 6783 | goto fail_alloc_iter; |
b04cc6b1 | 6784 | } |
b3806b43 | 6785 | |
3a161d99 | 6786 | trace_seq_init(&iter->seq); |
d716ff71 | 6787 | iter->trace = tr->current_trace; |
d7350c3f | 6788 | |
4462344e | 6789 | if (!alloc_cpumask_var(&iter->started, GFP_KERNEL)) { |
b04cc6b1 | 6790 | ret = -ENOMEM; |
d7350c3f | 6791 | goto fail; |
4462344e RR |
6792 | } |
6793 | ||
a309720c | 6794 | /* trace pipe does not show start of buffer */ |
4462344e | 6795 | cpumask_setall(iter->started); |
a309720c | 6796 | |
983f938a | 6797 | if (tr->trace_flags & TRACE_ITER_LATENCY_FMT) |
112f38a7 SR |
6798 | iter->iter_flags |= TRACE_FILE_LAT_FMT; |
6799 | ||
8be0709f | 6800 | /* Output in nanoseconds only if we are using a clock in nanoseconds. */ |
58e8eedf | 6801 | if (trace_clocks[tr->clock_id].in_ns) |
8be0709f DS |
6802 | iter->iter_flags |= TRACE_FILE_TIME_IN_NS; |
6803 | ||
15544209 | 6804 | iter->tr = tr; |
1c5eb448 | 6805 | iter->array_buffer = &tr->array_buffer; |
c2489bb7 | 6806 | iter->cpu_file = cpu; |
d7350c3f | 6807 | mutex_init(&iter->mutex); |
b3806b43 SR |
6808 | filp->private_data = iter; |
6809 | ||
107bad8b SR |
6810 | if (iter->trace->pipe_open) |
6811 | iter->trace->pipe_open(iter); | |
107bad8b | 6812 | |
b444786f | 6813 | nonseekable_open(inode, filp); |
cf6ab6d9 | 6814 | |
7ef282e0 | 6815 | tr->trace_ref++; |
c2489bb7 | 6816 | |
b04cc6b1 FW |
6817 | mutex_unlock(&trace_types_lock); |
6818 | return ret; | |
d7350c3f FW |
6819 | |
6820 | fail: | |
d7350c3f | 6821 | kfree(iter); |
c2489bb7 ZY |
6822 | fail_alloc_iter: |
6823 | close_pipe_on_cpu(tr, cpu); | |
6824 | fail_pipe_on_cpu: | |
7b85af63 | 6825 | __trace_array_put(tr); |
d7350c3f FW |
6826 | mutex_unlock(&trace_types_lock); |
6827 | return ret; | |
b3806b43 SR |
6828 | } |
6829 | ||
6830 | static int tracing_release_pipe(struct inode *inode, struct file *file) | |
6831 | { | |
6832 | struct trace_iterator *iter = file->private_data; | |
15544209 | 6833 | struct trace_array *tr = inode->i_private; |
b3806b43 | 6834 | |
b04cc6b1 FW |
6835 | mutex_lock(&trace_types_lock); |
6836 | ||
7ef282e0 | 6837 | tr->trace_ref--; |
cf6ab6d9 | 6838 | |
29bf4a5e | 6839 | if (iter->trace->pipe_close) |
c521efd1 | 6840 | iter->trace->pipe_close(iter); |
c2489bb7 | 6841 | close_pipe_on_cpu(tr, iter->cpu_file); |
b04cc6b1 FW |
6842 | mutex_unlock(&trace_types_lock); |
6843 | ||
6bba9288 | 6844 | free_trace_iter_content(iter); |
b3806b43 | 6845 | kfree(iter); |
b3806b43 | 6846 | |
7b85af63 SRRH |
6847 | trace_array_put(tr); |
6848 | ||
b3806b43 SR |
6849 | return 0; |
6850 | } | |
6851 | ||
9dd95748 | 6852 | static __poll_t |
cc60cdc9 | 6853 | trace_poll(struct trace_iterator *iter, struct file *filp, poll_table *poll_table) |
2a2cc8f7 | 6854 | { |
983f938a SRRH |
6855 | struct trace_array *tr = iter->tr; |
6856 | ||
15693458 SRRH |
6857 | /* Iterators are static, they should be filled or empty */ |
6858 | if (trace_buffer_iter(iter, iter->cpu_file)) | |
a9a08845 | 6859 | return EPOLLIN | EPOLLRDNORM; |
2a2cc8f7 | 6860 | |
983f938a | 6861 | if (tr->trace_flags & TRACE_ITER_BLOCK) |
2a2cc8f7 SSP |
6862 | /* |
6863 | * Always select as readable when in blocking mode | |
6864 | */ | |
a9a08845 | 6865 | return EPOLLIN | EPOLLRDNORM; |
15693458 | 6866 | else |
1c5eb448 | 6867 | return ring_buffer_poll_wait(iter->array_buffer->buffer, iter->cpu_file, |
42fb0a1e | 6868 | filp, poll_table, iter->tr->buffer_percent); |
2a2cc8f7 | 6869 | } |
2a2cc8f7 | 6870 | |
9dd95748 | 6871 | static __poll_t |
cc60cdc9 SR |
6872 | tracing_poll_pipe(struct file *filp, poll_table *poll_table) |
6873 | { | |
6874 | struct trace_iterator *iter = filp->private_data; | |
6875 | ||
6876 | return trace_poll(iter, filp, poll_table); | |
2a2cc8f7 SSP |
6877 | } |
6878 | ||
d716ff71 | 6879 | /* Must be called with iter->mutex held. */ |
ff98781b | 6880 | static int tracing_wait_pipe(struct file *filp) |
b3806b43 SR |
6881 | { |
6882 | struct trace_iterator *iter = filp->private_data; | |
8b8b3683 | 6883 | int ret; |
b3806b43 | 6884 | |
b3806b43 | 6885 | while (trace_empty(iter)) { |
2dc8f095 | 6886 | |
107bad8b | 6887 | if ((filp->f_flags & O_NONBLOCK)) { |
ff98781b | 6888 | return -EAGAIN; |
107bad8b | 6889 | } |
2dc8f095 | 6890 | |
b3806b43 | 6891 | /* |
250bfd3d | 6892 | * We block until we read something and tracing is disabled. |
b3806b43 SR |
6893 | * We still block if tracing is disabled, but we have never |
6894 | * read anything. This allows a user to cat this file, and | |
6895 | * then enable tracing. But after we have read something, | |
6896 | * we give an EOF when tracing is again disabled. | |
6897 | * | |
6898 | * iter->pos will be 0 if we haven't read anything. | |
6899 | */ | |
75df6e68 | 6900 | if (!tracer_tracing_is_on(iter->tr) && iter->pos) |
b3806b43 | 6901 | break; |
f4874261 SRRH |
6902 | |
6903 | mutex_unlock(&iter->mutex); | |
6904 | ||
2c2b0a78 | 6905 | ret = wait_on_pipe(iter, 0); |
f4874261 SRRH |
6906 | |
6907 | mutex_lock(&iter->mutex); | |
6908 | ||
8b8b3683 SRRH |
6909 | if (ret) |
6910 | return ret; | |
b3806b43 SR |
6911 | } |
6912 | ||
ff98781b EGM |
6913 | return 1; |
6914 | } | |
6915 | ||
6916 | /* | |
6917 | * Consumer reader. | |
6918 | */ | |
6919 | static ssize_t | |
6920 | tracing_read_pipe(struct file *filp, char __user *ubuf, | |
6921 | size_t cnt, loff_t *ppos) | |
6922 | { | |
6923 | struct trace_iterator *iter = filp->private_data; | |
6924 | ssize_t sret; | |
6925 | ||
d7350c3f FW |
6926 | /* |
6927 | * Avoid more than one consumer on a single file descriptor | |
6928 | * This is just a matter of traces coherency, the ring buffer itself | |
6929 | * is protected. | |
6930 | */ | |
6931 | mutex_lock(&iter->mutex); | |
1245800c SRRH |
6932 | |
6933 | /* return any leftover data */ | |
6934 | sret = trace_seq_to_user(&iter->seq, ubuf, cnt); | |
6935 | if (sret != -EBUSY) | |
6936 | goto out; | |
6937 | ||
6938 | trace_seq_init(&iter->seq); | |
6939 | ||
ff98781b EGM |
6940 | if (iter->trace->read) { |
6941 | sret = iter->trace->read(iter, filp, ubuf, cnt, ppos); | |
6942 | if (sret) | |
6943 | goto out; | |
6944 | } | |
6945 | ||
6946 | waitagain: | |
6947 | sret = tracing_wait_pipe(filp); | |
6948 | if (sret <= 0) | |
6949 | goto out; | |
6950 | ||
b3806b43 | 6951 | /* stop when tracing is finished */ |
ff98781b EGM |
6952 | if (trace_empty(iter)) { |
6953 | sret = 0; | |
107bad8b | 6954 | goto out; |
ff98781b | 6955 | } |
b3806b43 SR |
6956 | |
6957 | if (cnt >= PAGE_SIZE) | |
6958 | cnt = PAGE_SIZE - 1; | |
6959 | ||
53d0aa77 | 6960 | /* reset all but tr, trace, and overruns */ |
2768c1e7 | 6961 | trace_iterator_reset(iter); |
ed5467da | 6962 | cpumask_clear(iter->started); |
d303de1f | 6963 | trace_seq_init(&iter->seq); |
b3806b43 | 6964 | |
4f535968 | 6965 | trace_event_read_lock(); |
7e53bd42 | 6966 | trace_access_lock(iter->cpu_file); |
955b61e5 | 6967 | while (trace_find_next_entry_inc(iter) != NULL) { |
2c4f035f | 6968 | enum print_line_t ret; |
5ac48378 | 6969 | int save_len = iter->seq.seq.len; |
088b1e42 | 6970 | |
f9896bf3 | 6971 | ret = print_trace_line(iter); |
2c4f035f | 6972 | if (ret == TRACE_TYPE_PARTIAL_LINE) { |
c1ac03af YJ |
6973 | /* |
6974 | * If one print_trace_line() fills entire trace_seq in one shot, | |
6975 | * trace_seq_to_user() will returns -EBUSY because save_len == 0, | |
6976 | * In this case, we need to consume it, otherwise, loop will peek | |
6977 | * this event next time, resulting in an infinite loop. | |
6978 | */ | |
6979 | if (save_len == 0) { | |
6980 | iter->seq.full = 0; | |
6981 | trace_seq_puts(&iter->seq, "[LINE TOO BIG]\n"); | |
6982 | trace_consume(iter); | |
6983 | break; | |
6984 | } | |
6985 | ||
6986 | /* In other cases, don't print partial lines */ | |
5ac48378 | 6987 | iter->seq.seq.len = save_len; |
b3806b43 | 6988 | break; |
088b1e42 | 6989 | } |
b91facc3 FW |
6990 | if (ret != TRACE_TYPE_NO_CONSUME) |
6991 | trace_consume(iter); | |
b3806b43 | 6992 | |
5ac48378 | 6993 | if (trace_seq_used(&iter->seq) >= cnt) |
b3806b43 | 6994 | break; |
ee5e51f5 JO |
6995 | |
6996 | /* | |
6997 | * Setting the full flag means we reached the trace_seq buffer | |
6998 | * size and we should leave by partial output condition above. | |
6999 | * One of the trace_seq_* functions is not used properly. | |
7000 | */ | |
7001 | WARN_ONCE(iter->seq.full, "full flag set for trace type %d", | |
7002 | iter->ent->type); | |
b3806b43 | 7003 | } |
7e53bd42 | 7004 | trace_access_unlock(iter->cpu_file); |
4f535968 | 7005 | trace_event_read_unlock(); |
b3806b43 | 7006 | |
b3806b43 | 7007 | /* Now copy what we have to the user */ |
6c6c2796 | 7008 | sret = trace_seq_to_user(&iter->seq, ubuf, cnt); |
5ac48378 | 7009 | if (iter->seq.seq.readpos >= trace_seq_used(&iter->seq)) |
f9520750 | 7010 | trace_seq_init(&iter->seq); |
9ff4b974 PP |
7011 | |
7012 | /* | |
25985edc | 7013 | * If there was nothing to send to user, in spite of consuming trace |
9ff4b974 PP |
7014 | * entries, go back to wait for more entries. |
7015 | */ | |
6c6c2796 | 7016 | if (sret == -EBUSY) |
9ff4b974 | 7017 | goto waitagain; |
b3806b43 | 7018 | |
107bad8b | 7019 | out: |
d7350c3f | 7020 | mutex_unlock(&iter->mutex); |
107bad8b | 7021 | |
6c6c2796 | 7022 | return sret; |
b3806b43 SR |
7023 | } |
7024 | ||
3c56819b EGM |
7025 | static void tracing_spd_release_pipe(struct splice_pipe_desc *spd, |
7026 | unsigned int idx) | |
7027 | { | |
7028 | __free_page(spd->pages[idx]); | |
7029 | } | |
7030 | ||
34cd4998 | 7031 | static size_t |
fa7c7f6e | 7032 | tracing_fill_pipe_page(size_t rem, struct trace_iterator *iter) |
34cd4998 SR |
7033 | { |
7034 | size_t count; | |
74f06bb7 | 7035 | int save_len; |
34cd4998 SR |
7036 | int ret; |
7037 | ||
7038 | /* Seq buffer is page-sized, exactly what we need. */ | |
7039 | for (;;) { | |
74f06bb7 | 7040 | save_len = iter->seq.seq.len; |
34cd4998 | 7041 | ret = print_trace_line(iter); |
74f06bb7 SRRH |
7042 | |
7043 | if (trace_seq_has_overflowed(&iter->seq)) { | |
7044 | iter->seq.seq.len = save_len; | |
34cd4998 SR |
7045 | break; |
7046 | } | |
74f06bb7 SRRH |
7047 | |
7048 | /* | |
7049 | * This should not be hit, because it should only | |
7050 | * be set if the iter->seq overflowed. But check it | |
7051 | * anyway to be safe. | |
7052 | */ | |
34cd4998 | 7053 | if (ret == TRACE_TYPE_PARTIAL_LINE) { |
74f06bb7 SRRH |
7054 | iter->seq.seq.len = save_len; |
7055 | break; | |
7056 | } | |
7057 | ||
5ac48378 | 7058 | count = trace_seq_used(&iter->seq) - save_len; |
74f06bb7 SRRH |
7059 | if (rem < count) { |
7060 | rem = 0; | |
7061 | iter->seq.seq.len = save_len; | |
34cd4998 SR |
7062 | break; |
7063 | } | |
7064 | ||
74e7ff8c LJ |
7065 | if (ret != TRACE_TYPE_NO_CONSUME) |
7066 | trace_consume(iter); | |
34cd4998 | 7067 | rem -= count; |
955b61e5 | 7068 | if (!trace_find_next_entry_inc(iter)) { |
34cd4998 SR |
7069 | rem = 0; |
7070 | iter->ent = NULL; | |
7071 | break; | |
7072 | } | |
7073 | } | |
7074 | ||
7075 | return rem; | |
7076 | } | |
7077 | ||
3c56819b EGM |
7078 | static ssize_t tracing_splice_read_pipe(struct file *filp, |
7079 | loff_t *ppos, | |
7080 | struct pipe_inode_info *pipe, | |
7081 | size_t len, | |
7082 | unsigned int flags) | |
7083 | { | |
35f3d14d JA |
7084 | struct page *pages_def[PIPE_DEF_BUFFERS]; |
7085 | struct partial_page partial_def[PIPE_DEF_BUFFERS]; | |
3c56819b EGM |
7086 | struct trace_iterator *iter = filp->private_data; |
7087 | struct splice_pipe_desc spd = { | |
35f3d14d JA |
7088 | .pages = pages_def, |
7089 | .partial = partial_def, | |
34cd4998 | 7090 | .nr_pages = 0, /* This gets updated below. */ |
047fe360 | 7091 | .nr_pages_max = PIPE_DEF_BUFFERS, |
6797d97a | 7092 | .ops = &default_pipe_buf_ops, |
34cd4998 | 7093 | .spd_release = tracing_spd_release_pipe, |
3c56819b EGM |
7094 | }; |
7095 | ssize_t ret; | |
34cd4998 | 7096 | size_t rem; |
3c56819b EGM |
7097 | unsigned int i; |
7098 | ||
35f3d14d JA |
7099 | if (splice_grow_spd(pipe, &spd)) |
7100 | return -ENOMEM; | |
7101 | ||
d7350c3f | 7102 | mutex_lock(&iter->mutex); |
3c56819b EGM |
7103 | |
7104 | if (iter->trace->splice_read) { | |
7105 | ret = iter->trace->splice_read(iter, filp, | |
7106 | ppos, pipe, len, flags); | |
7107 | if (ret) | |
34cd4998 | 7108 | goto out_err; |
3c56819b EGM |
7109 | } |
7110 | ||
7111 | ret = tracing_wait_pipe(filp); | |
7112 | if (ret <= 0) | |
34cd4998 | 7113 | goto out_err; |
3c56819b | 7114 | |
955b61e5 | 7115 | if (!iter->ent && !trace_find_next_entry_inc(iter)) { |
3c56819b | 7116 | ret = -EFAULT; |
34cd4998 | 7117 | goto out_err; |
3c56819b EGM |
7118 | } |
7119 | ||
4f535968 | 7120 | trace_event_read_lock(); |
7e53bd42 | 7121 | trace_access_lock(iter->cpu_file); |
4f535968 | 7122 | |
3c56819b | 7123 | /* Fill as many pages as possible. */ |
a786c06d | 7124 | for (i = 0, rem = len; i < spd.nr_pages_max && rem; i++) { |
35f3d14d JA |
7125 | spd.pages[i] = alloc_page(GFP_KERNEL); |
7126 | if (!spd.pages[i]) | |
34cd4998 | 7127 | break; |
3c56819b | 7128 | |
fa7c7f6e | 7129 | rem = tracing_fill_pipe_page(rem, iter); |
3c56819b EGM |
7130 | |
7131 | /* Copy the data into the page, so we can start over. */ | |
7132 | ret = trace_seq_to_buffer(&iter->seq, | |
35f3d14d | 7133 | page_address(spd.pages[i]), |
5ac48378 | 7134 | trace_seq_used(&iter->seq)); |
3c56819b | 7135 | if (ret < 0) { |
35f3d14d | 7136 | __free_page(spd.pages[i]); |
3c56819b EGM |
7137 | break; |
7138 | } | |
35f3d14d | 7139 | spd.partial[i].offset = 0; |
5ac48378 | 7140 | spd.partial[i].len = trace_seq_used(&iter->seq); |
3c56819b | 7141 | |
f9520750 | 7142 | trace_seq_init(&iter->seq); |
3c56819b EGM |
7143 | } |
7144 | ||
7e53bd42 | 7145 | trace_access_unlock(iter->cpu_file); |
4f535968 | 7146 | trace_event_read_unlock(); |
d7350c3f | 7147 | mutex_unlock(&iter->mutex); |
3c56819b EGM |
7148 | |
7149 | spd.nr_pages = i; | |
7150 | ||
a29054d9 SRRH |
7151 | if (i) |
7152 | ret = splice_to_pipe(pipe, &spd); | |
7153 | else | |
7154 | ret = 0; | |
35f3d14d | 7155 | out: |
047fe360 | 7156 | splice_shrink_spd(&spd); |
35f3d14d | 7157 | return ret; |
3c56819b | 7158 | |
34cd4998 | 7159 | out_err: |
d7350c3f | 7160 | mutex_unlock(&iter->mutex); |
35f3d14d | 7161 | goto out; |
3c56819b EGM |
7162 | } |
7163 | ||
a98a3c3f SR |
7164 | static ssize_t |
7165 | tracing_entries_read(struct file *filp, char __user *ubuf, | |
7166 | size_t cnt, loff_t *ppos) | |
7167 | { | |
0bc392ee ON |
7168 | struct inode *inode = file_inode(filp); |
7169 | struct trace_array *tr = inode->i_private; | |
7170 | int cpu = tracing_get_cpu(inode); | |
438ced17 VN |
7171 | char buf[64]; |
7172 | int r = 0; | |
7173 | ssize_t ret; | |
a98a3c3f | 7174 | |
db526ca3 | 7175 | mutex_lock(&trace_types_lock); |
438ced17 | 7176 | |
0bc392ee | 7177 | if (cpu == RING_BUFFER_ALL_CPUS) { |
438ced17 VN |
7178 | int cpu, buf_size_same; |
7179 | unsigned long size; | |
7180 | ||
7181 | size = 0; | |
7182 | buf_size_same = 1; | |
7183 | /* check if all cpu sizes are same */ | |
7184 | for_each_tracing_cpu(cpu) { | |
7185 | /* fill in the size from first enabled cpu */ | |
7186 | if (size == 0) | |
1c5eb448 SRV |
7187 | size = per_cpu_ptr(tr->array_buffer.data, cpu)->entries; |
7188 | if (size != per_cpu_ptr(tr->array_buffer.data, cpu)->entries) { | |
438ced17 VN |
7189 | buf_size_same = 0; |
7190 | break; | |
7191 | } | |
7192 | } | |
7193 | ||
7194 | if (buf_size_same) { | |
7195 | if (!ring_buffer_expanded) | |
7196 | r = sprintf(buf, "%lu (expanded: %lu)\n", | |
7197 | size >> 10, | |
7198 | trace_buf_size >> 10); | |
7199 | else | |
7200 | r = sprintf(buf, "%lu\n", size >> 10); | |
7201 | } else | |
7202 | r = sprintf(buf, "X\n"); | |
7203 | } else | |
1c5eb448 | 7204 | r = sprintf(buf, "%lu\n", per_cpu_ptr(tr->array_buffer.data, cpu)->entries >> 10); |
438ced17 | 7205 | |
db526ca3 SR |
7206 | mutex_unlock(&trace_types_lock); |
7207 | ||
438ced17 VN |
7208 | ret = simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
7209 | return ret; | |
a98a3c3f SR |
7210 | } |
7211 | ||
7212 | static ssize_t | |
7213 | tracing_entries_write(struct file *filp, const char __user *ubuf, | |
7214 | size_t cnt, loff_t *ppos) | |
7215 | { | |
0bc392ee ON |
7216 | struct inode *inode = file_inode(filp); |
7217 | struct trace_array *tr = inode->i_private; | |
a98a3c3f | 7218 | unsigned long val; |
4f271a2a | 7219 | int ret; |
a98a3c3f | 7220 | |
22fe9b54 PH |
7221 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
7222 | if (ret) | |
c6caeeb1 | 7223 | return ret; |
a98a3c3f SR |
7224 | |
7225 | /* must have at least 1 entry */ | |
7226 | if (!val) | |
7227 | return -EINVAL; | |
7228 | ||
1696b2b0 SR |
7229 | /* value is in KB */ |
7230 | val <<= 10; | |
0bc392ee | 7231 | ret = tracing_resize_ring_buffer(tr, val, tracing_get_cpu(inode)); |
4f271a2a VN |
7232 | if (ret < 0) |
7233 | return ret; | |
a98a3c3f | 7234 | |
cf8517cf | 7235 | *ppos += cnt; |
a98a3c3f | 7236 | |
4f271a2a VN |
7237 | return cnt; |
7238 | } | |
bf5e6519 | 7239 | |
f81ab074 VN |
7240 | static ssize_t |
7241 | tracing_total_entries_read(struct file *filp, char __user *ubuf, | |
7242 | size_t cnt, loff_t *ppos) | |
7243 | { | |
7244 | struct trace_array *tr = filp->private_data; | |
7245 | char buf[64]; | |
7246 | int r, cpu; | |
7247 | unsigned long size = 0, expanded_size = 0; | |
7248 | ||
7249 | mutex_lock(&trace_types_lock); | |
7250 | for_each_tracing_cpu(cpu) { | |
1c5eb448 | 7251 | size += per_cpu_ptr(tr->array_buffer.data, cpu)->entries >> 10; |
f81ab074 VN |
7252 | if (!ring_buffer_expanded) |
7253 | expanded_size += trace_buf_size >> 10; | |
7254 | } | |
7255 | if (ring_buffer_expanded) | |
7256 | r = sprintf(buf, "%lu\n", size); | |
7257 | else | |
7258 | r = sprintf(buf, "%lu (expanded: %lu)\n", size, expanded_size); | |
7259 | mutex_unlock(&trace_types_lock); | |
7260 | ||
7261 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
7262 | } | |
7263 | ||
4f271a2a VN |
7264 | static ssize_t |
7265 | tracing_free_buffer_write(struct file *filp, const char __user *ubuf, | |
7266 | size_t cnt, loff_t *ppos) | |
7267 | { | |
7268 | /* | |
7269 | * There is no need to read what the user has written, this function | |
7270 | * is just to make sure that there is no error when "echo" is used | |
7271 | */ | |
7272 | ||
7273 | *ppos += cnt; | |
a98a3c3f SR |
7274 | |
7275 | return cnt; | |
7276 | } | |
7277 | ||
4f271a2a VN |
7278 | static int |
7279 | tracing_free_buffer_release(struct inode *inode, struct file *filp) | |
7280 | { | |
2b6080f2 SR |
7281 | struct trace_array *tr = inode->i_private; |
7282 | ||
cf30cf67 | 7283 | /* disable tracing ? */ |
983f938a | 7284 | if (tr->trace_flags & TRACE_ITER_STOP_ON_FREE) |
711e1243 | 7285 | tracer_tracing_off(tr); |
4f271a2a | 7286 | /* resize the ring buffer to 0 */ |
2b6080f2 | 7287 | tracing_resize_ring_buffer(tr, 0, RING_BUFFER_ALL_CPUS); |
4f271a2a | 7288 | |
7b85af63 SRRH |
7289 | trace_array_put(tr); |
7290 | ||
4f271a2a VN |
7291 | return 0; |
7292 | } | |
7293 | ||
5bf9a1ee PP |
7294 | static ssize_t |
7295 | tracing_mark_write(struct file *filp, const char __user *ubuf, | |
7296 | size_t cnt, loff_t *fpos) | |
7297 | { | |
2d71619c | 7298 | struct trace_array *tr = filp->private_data; |
d696b58c | 7299 | struct ring_buffer_event *event; |
3dd80953 | 7300 | enum event_trigger_type tt = ETT_NONE; |
13292494 | 7301 | struct trace_buffer *buffer; |
d696b58c | 7302 | struct print_entry *entry; |
d696b58c | 7303 | ssize_t written; |
d696b58c SR |
7304 | int size; |
7305 | int len; | |
fa32e855 | 7306 | |
656c7f0d | 7307 | /* Used in tracing_mark_raw_write() as well */ |
0f5e5a3a RV |
7308 | #define FAULTED_STR "<faulted>" |
7309 | #define FAULTED_SIZE (sizeof(FAULTED_STR) - 1) /* '\0' is already accounted for */ | |
5bf9a1ee | 7310 | |
c76f0694 | 7311 | if (tracing_disabled) |
5bf9a1ee PP |
7312 | return -EINVAL; |
7313 | ||
983f938a | 7314 | if (!(tr->trace_flags & TRACE_ITER_MARKERS)) |
5224c3a3 MSB |
7315 | return -EINVAL; |
7316 | ||
5bf9a1ee PP |
7317 | if (cnt > TRACE_BUF_SIZE) |
7318 | cnt = TRACE_BUF_SIZE; | |
7319 | ||
d696b58c | 7320 | BUILD_BUG_ON(TRACE_BUF_SIZE >= PAGE_SIZE); |
5bf9a1ee | 7321 | |
656c7f0d | 7322 | size = sizeof(*entry) + cnt + 2; /* add '\0' and possible '\n' */ |
d696b58c | 7323 | |
656c7f0d SRRH |
7324 | /* If less than "<faulted>", then make sure we can still add that */ |
7325 | if (cnt < FAULTED_SIZE) | |
7326 | size += FAULTED_SIZE - cnt; | |
d696b58c | 7327 | |
1c5eb448 | 7328 | buffer = tr->array_buffer.buffer; |
3e9a8aad | 7329 | event = __trace_buffer_lock_reserve(buffer, TRACE_PRINT, size, |
36590c50 | 7330 | tracing_gen_ctx()); |
656c7f0d | 7331 | if (unlikely(!event)) |
d696b58c | 7332 | /* Ring buffer disabled, return as if not open for write */ |
656c7f0d | 7333 | return -EBADF; |
d696b58c SR |
7334 | |
7335 | entry = ring_buffer_event_data(event); | |
7336 | entry->ip = _THIS_IP_; | |
7337 | ||
656c7f0d SRRH |
7338 | len = __copy_from_user_inatomic(&entry->buf, ubuf, cnt); |
7339 | if (len) { | |
0f5e5a3a | 7340 | memcpy(&entry->buf, FAULTED_STR, FAULTED_SIZE); |
656c7f0d SRRH |
7341 | cnt = FAULTED_SIZE; |
7342 | written = -EFAULT; | |
c13d2f7c | 7343 | } else |
656c7f0d | 7344 | written = cnt; |
5bf9a1ee | 7345 | |
3dd80953 SRV |
7346 | if (tr->trace_marker_file && !list_empty(&tr->trace_marker_file->triggers)) { |
7347 | /* do not add \n before testing triggers, but add \0 */ | |
7348 | entry->buf[cnt] = '\0'; | |
b47e3302 | 7349 | tt = event_triggers_call(tr->trace_marker_file, buffer, entry, event); |
3dd80953 SRV |
7350 | } |
7351 | ||
d696b58c SR |
7352 | if (entry->buf[cnt - 1] != '\n') { |
7353 | entry->buf[cnt] = '\n'; | |
7354 | entry->buf[cnt + 1] = '\0'; | |
7355 | } else | |
7356 | entry->buf[cnt] = '\0'; | |
7357 | ||
458999c6 TZ |
7358 | if (static_branch_unlikely(&trace_marker_exports_enabled)) |
7359 | ftrace_exports(event, TRACE_EXPORT_MARKER); | |
7ffbd48d | 7360 | __buffer_unlock_commit(buffer, event); |
5bf9a1ee | 7361 | |
3dd80953 SRV |
7362 | if (tt) |
7363 | event_triggers_post_call(tr->trace_marker_file, tt); | |
7364 | ||
fa32e855 SR |
7365 | return written; |
7366 | } | |
7367 | ||
7368 | /* Limit it for now to 3K (including tag) */ | |
7369 | #define RAW_DATA_MAX_SIZE (1024*3) | |
7370 | ||
7371 | static ssize_t | |
7372 | tracing_mark_raw_write(struct file *filp, const char __user *ubuf, | |
7373 | size_t cnt, loff_t *fpos) | |
7374 | { | |
7375 | struct trace_array *tr = filp->private_data; | |
7376 | struct ring_buffer_event *event; | |
13292494 | 7377 | struct trace_buffer *buffer; |
fa32e855 | 7378 | struct raw_data_entry *entry; |
fa32e855 | 7379 | ssize_t written; |
fa32e855 SR |
7380 | int size; |
7381 | int len; | |
7382 | ||
656c7f0d SRRH |
7383 | #define FAULT_SIZE_ID (FAULTED_SIZE + sizeof(int)) |
7384 | ||
fa32e855 SR |
7385 | if (tracing_disabled) |
7386 | return -EINVAL; | |
7387 | ||
7388 | if (!(tr->trace_flags & TRACE_ITER_MARKERS)) | |
7389 | return -EINVAL; | |
7390 | ||
7391 | /* The marker must at least have a tag id */ | |
7392 | if (cnt < sizeof(unsigned int) || cnt > RAW_DATA_MAX_SIZE) | |
7393 | return -EINVAL; | |
7394 | ||
7395 | if (cnt > TRACE_BUF_SIZE) | |
7396 | cnt = TRACE_BUF_SIZE; | |
7397 | ||
7398 | BUILD_BUG_ON(TRACE_BUF_SIZE >= PAGE_SIZE); | |
7399 | ||
fa32e855 | 7400 | size = sizeof(*entry) + cnt; |
656c7f0d SRRH |
7401 | if (cnt < FAULT_SIZE_ID) |
7402 | size += FAULT_SIZE_ID - cnt; | |
7403 | ||
1c5eb448 | 7404 | buffer = tr->array_buffer.buffer; |
3e9a8aad | 7405 | event = __trace_buffer_lock_reserve(buffer, TRACE_RAW_DATA, size, |
36590c50 | 7406 | tracing_gen_ctx()); |
656c7f0d | 7407 | if (!event) |
fa32e855 | 7408 | /* Ring buffer disabled, return as if not open for write */ |
656c7f0d | 7409 | return -EBADF; |
fa32e855 SR |
7410 | |
7411 | entry = ring_buffer_event_data(event); | |
7412 | ||
656c7f0d SRRH |
7413 | len = __copy_from_user_inatomic(&entry->id, ubuf, cnt); |
7414 | if (len) { | |
7415 | entry->id = -1; | |
0f5e5a3a | 7416 | memcpy(&entry->buf, FAULTED_STR, FAULTED_SIZE); |
656c7f0d | 7417 | written = -EFAULT; |
fa32e855 | 7418 | } else |
656c7f0d | 7419 | written = cnt; |
fa32e855 SR |
7420 | |
7421 | __buffer_unlock_commit(buffer, event); | |
7422 | ||
1aa54bca | 7423 | return written; |
5bf9a1ee PP |
7424 | } |
7425 | ||
13f16d20 | 7426 | static int tracing_clock_show(struct seq_file *m, void *v) |
5079f326 | 7427 | { |
2b6080f2 | 7428 | struct trace_array *tr = m->private; |
5079f326 Z |
7429 | int i; |
7430 | ||
7431 | for (i = 0; i < ARRAY_SIZE(trace_clocks); i++) | |
13f16d20 | 7432 | seq_printf(m, |
5079f326 | 7433 | "%s%s%s%s", i ? " " : "", |
2b6080f2 SR |
7434 | i == tr->clock_id ? "[" : "", trace_clocks[i].name, |
7435 | i == tr->clock_id ? "]" : ""); | |
13f16d20 | 7436 | seq_putc(m, '\n'); |
5079f326 | 7437 | |
13f16d20 | 7438 | return 0; |
5079f326 Z |
7439 | } |
7440 | ||
d71bd34d | 7441 | int tracing_set_clock(struct trace_array *tr, const char *clockstr) |
5079f326 | 7442 | { |
5079f326 Z |
7443 | int i; |
7444 | ||
5079f326 Z |
7445 | for (i = 0; i < ARRAY_SIZE(trace_clocks); i++) { |
7446 | if (strcmp(trace_clocks[i].name, clockstr) == 0) | |
7447 | break; | |
7448 | } | |
7449 | if (i == ARRAY_SIZE(trace_clocks)) | |
7450 | return -EINVAL; | |
7451 | ||
5079f326 Z |
7452 | mutex_lock(&trace_types_lock); |
7453 | ||
2b6080f2 SR |
7454 | tr->clock_id = i; |
7455 | ||
1c5eb448 | 7456 | ring_buffer_set_clock(tr->array_buffer.buffer, trace_clocks[i].func); |
5079f326 | 7457 | |
60303ed3 DS |
7458 | /* |
7459 | * New clock may not be consistent with the previous clock. | |
7460 | * Reset the buffer so that it doesn't have incomparable timestamps. | |
7461 | */ | |
1c5eb448 | 7462 | tracing_reset_online_cpus(&tr->array_buffer); |
12883efb SRRH |
7463 | |
7464 | #ifdef CONFIG_TRACER_MAX_TRACE | |
170b3b10 | 7465 | if (tr->max_buffer.buffer) |
12883efb | 7466 | ring_buffer_set_clock(tr->max_buffer.buffer, trace_clocks[i].func); |
9457158b | 7467 | tracing_reset_online_cpus(&tr->max_buffer); |
12883efb | 7468 | #endif |
60303ed3 | 7469 | |
5079f326 Z |
7470 | mutex_unlock(&trace_types_lock); |
7471 | ||
e1e232ca SR |
7472 | return 0; |
7473 | } | |
7474 | ||
7475 | static ssize_t tracing_clock_write(struct file *filp, const char __user *ubuf, | |
7476 | size_t cnt, loff_t *fpos) | |
7477 | { | |
7478 | struct seq_file *m = filp->private_data; | |
7479 | struct trace_array *tr = m->private; | |
7480 | char buf[64]; | |
7481 | const char *clockstr; | |
7482 | int ret; | |
7483 | ||
7484 | if (cnt >= sizeof(buf)) | |
7485 | return -EINVAL; | |
7486 | ||
4afe6495 | 7487 | if (copy_from_user(buf, ubuf, cnt)) |
e1e232ca SR |
7488 | return -EFAULT; |
7489 | ||
7490 | buf[cnt] = 0; | |
7491 | ||
7492 | clockstr = strstrip(buf); | |
7493 | ||
7494 | ret = tracing_set_clock(tr, clockstr); | |
7495 | if (ret) | |
7496 | return ret; | |
7497 | ||
5079f326 Z |
7498 | *fpos += cnt; |
7499 | ||
7500 | return cnt; | |
7501 | } | |
7502 | ||
13f16d20 LZ |
7503 | static int tracing_clock_open(struct inode *inode, struct file *file) |
7504 | { | |
7b85af63 SRRH |
7505 | struct trace_array *tr = inode->i_private; |
7506 | int ret; | |
7507 | ||
8530dec6 SRV |
7508 | ret = tracing_check_open_get_tr(tr); |
7509 | if (ret) | |
7510 | return ret; | |
7b85af63 SRRH |
7511 | |
7512 | ret = single_open(file, tracing_clock_show, inode->i_private); | |
7513 | if (ret < 0) | |
7514 | trace_array_put(tr); | |
7515 | ||
7516 | return ret; | |
13f16d20 LZ |
7517 | } |
7518 | ||
2c1ea60b TZ |
7519 | static int tracing_time_stamp_mode_show(struct seq_file *m, void *v) |
7520 | { | |
7521 | struct trace_array *tr = m->private; | |
7522 | ||
7523 | mutex_lock(&trace_types_lock); | |
7524 | ||
1c5eb448 | 7525 | if (ring_buffer_time_stamp_abs(tr->array_buffer.buffer)) |
2c1ea60b TZ |
7526 | seq_puts(m, "delta [absolute]\n"); |
7527 | else | |
7528 | seq_puts(m, "[delta] absolute\n"); | |
7529 | ||
7530 | mutex_unlock(&trace_types_lock); | |
7531 | ||
7532 | return 0; | |
7533 | } | |
7534 | ||
7535 | static int tracing_time_stamp_mode_open(struct inode *inode, struct file *file) | |
7536 | { | |
7537 | struct trace_array *tr = inode->i_private; | |
7538 | int ret; | |
7539 | ||
8530dec6 SRV |
7540 | ret = tracing_check_open_get_tr(tr); |
7541 | if (ret) | |
7542 | return ret; | |
2c1ea60b TZ |
7543 | |
7544 | ret = single_open(file, tracing_time_stamp_mode_show, inode->i_private); | |
7545 | if (ret < 0) | |
7546 | trace_array_put(tr); | |
7547 | ||
7548 | return ret; | |
7549 | } | |
7550 | ||
d8279bfc SRV |
7551 | u64 tracing_event_time_stamp(struct trace_buffer *buffer, struct ring_buffer_event *rbe) |
7552 | { | |
7553 | if (rbe == this_cpu_read(trace_buffered_event)) | |
f3ef7202 | 7554 | return ring_buffer_time_stamp(buffer); |
d8279bfc SRV |
7555 | |
7556 | return ring_buffer_event_time_stamp(buffer, rbe); | |
7557 | } | |
7558 | ||
b94bc80d SRV |
7559 | /* |
7560 | * Set or disable using the per CPU trace_buffer_event when possible. | |
7561 | */ | |
7562 | int tracing_set_filter_buffering(struct trace_array *tr, bool set) | |
00b41452 TZ |
7563 | { |
7564 | int ret = 0; | |
7565 | ||
7566 | mutex_lock(&trace_types_lock); | |
7567 | ||
b94bc80d | 7568 | if (set && tr->no_filter_buffering_ref++) |
00b41452 TZ |
7569 | goto out; |
7570 | ||
b94bc80d SRV |
7571 | if (!set) { |
7572 | if (WARN_ON_ONCE(!tr->no_filter_buffering_ref)) { | |
00b41452 TZ |
7573 | ret = -EINVAL; |
7574 | goto out; | |
7575 | } | |
7576 | ||
b94bc80d | 7577 | --tr->no_filter_buffering_ref; |
00b41452 | 7578 | } |
00b41452 TZ |
7579 | out: |
7580 | mutex_unlock(&trace_types_lock); | |
7581 | ||
7582 | return ret; | |
7583 | } | |
7584 | ||
6de58e62 SRRH |
7585 | struct ftrace_buffer_info { |
7586 | struct trace_iterator iter; | |
7587 | void *spare; | |
73a757e6 | 7588 | unsigned int spare_cpu; |
6de58e62 SRRH |
7589 | unsigned int read; |
7590 | }; | |
7591 | ||
debdd57f HT |
7592 | #ifdef CONFIG_TRACER_SNAPSHOT |
7593 | static int tracing_snapshot_open(struct inode *inode, struct file *file) | |
7594 | { | |
6484c71c | 7595 | struct trace_array *tr = inode->i_private; |
debdd57f | 7596 | struct trace_iterator *iter; |
2b6080f2 | 7597 | struct seq_file *m; |
8530dec6 | 7598 | int ret; |
debdd57f | 7599 | |
8530dec6 SRV |
7600 | ret = tracing_check_open_get_tr(tr); |
7601 | if (ret) | |
7602 | return ret; | |
ff451961 | 7603 | |
debdd57f | 7604 | if (file->f_mode & FMODE_READ) { |
6484c71c | 7605 | iter = __tracing_open(inode, file, true); |
debdd57f HT |
7606 | if (IS_ERR(iter)) |
7607 | ret = PTR_ERR(iter); | |
2b6080f2 SR |
7608 | } else { |
7609 | /* Writes still need the seq_file to hold the private data */ | |
f77d09a3 | 7610 | ret = -ENOMEM; |
2b6080f2 SR |
7611 | m = kzalloc(sizeof(*m), GFP_KERNEL); |
7612 | if (!m) | |
f77d09a3 | 7613 | goto out; |
2b6080f2 SR |
7614 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); |
7615 | if (!iter) { | |
7616 | kfree(m); | |
f77d09a3 | 7617 | goto out; |
2b6080f2 | 7618 | } |
f77d09a3 AL |
7619 | ret = 0; |
7620 | ||
ff451961 | 7621 | iter->tr = tr; |
1c5eb448 | 7622 | iter->array_buffer = &tr->max_buffer; |
6484c71c | 7623 | iter->cpu_file = tracing_get_cpu(inode); |
2b6080f2 SR |
7624 | m->private = iter; |
7625 | file->private_data = m; | |
debdd57f | 7626 | } |
f77d09a3 | 7627 | out: |
ff451961 SRRH |
7628 | if (ret < 0) |
7629 | trace_array_put(tr); | |
7630 | ||
debdd57f HT |
7631 | return ret; |
7632 | } | |
7633 | ||
3163f635 ZY |
7634 | static void tracing_swap_cpu_buffer(void *tr) |
7635 | { | |
7636 | update_max_tr_single((struct trace_array *)tr, current, smp_processor_id()); | |
7637 | } | |
7638 | ||
debdd57f HT |
7639 | static ssize_t |
7640 | tracing_snapshot_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
7641 | loff_t *ppos) | |
7642 | { | |
2b6080f2 SR |
7643 | struct seq_file *m = filp->private_data; |
7644 | struct trace_iterator *iter = m->private; | |
7645 | struct trace_array *tr = iter->tr; | |
debdd57f HT |
7646 | unsigned long val; |
7647 | int ret; | |
7648 | ||
7649 | ret = tracing_update_buffers(); | |
7650 | if (ret < 0) | |
7651 | return ret; | |
7652 | ||
7653 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); | |
7654 | if (ret) | |
7655 | return ret; | |
7656 | ||
7657 | mutex_lock(&trace_types_lock); | |
7658 | ||
2b6080f2 | 7659 | if (tr->current_trace->use_max_tr) { |
debdd57f HT |
7660 | ret = -EBUSY; |
7661 | goto out; | |
7662 | } | |
7663 | ||
c0a581d7 | 7664 | local_irq_disable(); |
a35873a0 TZ |
7665 | arch_spin_lock(&tr->max_lock); |
7666 | if (tr->cond_snapshot) | |
7667 | ret = -EBUSY; | |
7668 | arch_spin_unlock(&tr->max_lock); | |
c0a581d7 | 7669 | local_irq_enable(); |
a35873a0 TZ |
7670 | if (ret) |
7671 | goto out; | |
7672 | ||
debdd57f HT |
7673 | switch (val) { |
7674 | case 0: | |
f1affcaa SRRH |
7675 | if (iter->cpu_file != RING_BUFFER_ALL_CPUS) { |
7676 | ret = -EINVAL; | |
7677 | break; | |
debdd57f | 7678 | } |
3209cff4 SRRH |
7679 | if (tr->allocated_snapshot) |
7680 | free_snapshot(tr); | |
debdd57f HT |
7681 | break; |
7682 | case 1: | |
f1affcaa SRRH |
7683 | /* Only allow per-cpu swap if the ring buffer supports it */ |
7684 | #ifndef CONFIG_RING_BUFFER_ALLOW_SWAP | |
7685 | if (iter->cpu_file != RING_BUFFER_ALL_CPUS) { | |
7686 | ret = -EINVAL; | |
7687 | break; | |
7688 | } | |
7689 | #endif | |
46cc0b44 ET |
7690 | if (tr->allocated_snapshot) |
7691 | ret = resize_buffer_duplicate_size(&tr->max_buffer, | |
1c5eb448 | 7692 | &tr->array_buffer, iter->cpu_file); |
46cc0b44 | 7693 | else |
2824f503 | 7694 | ret = tracing_alloc_snapshot_instance(tr); |
46cc0b44 ET |
7695 | if (ret < 0) |
7696 | break; | |
debdd57f | 7697 | /* Now, we're going to swap */ |
3163f635 ZY |
7698 | if (iter->cpu_file == RING_BUFFER_ALL_CPUS) { |
7699 | local_irq_disable(); | |
a35873a0 | 7700 | update_max_tr(tr, current, smp_processor_id(), NULL); |
3163f635 ZY |
7701 | local_irq_enable(); |
7702 | } else { | |
7703 | smp_call_function_single(iter->cpu_file, tracing_swap_cpu_buffer, | |
7704 | (void *)tr, 1); | |
7705 | } | |
debdd57f HT |
7706 | break; |
7707 | default: | |
45ad21ca | 7708 | if (tr->allocated_snapshot) { |
f1affcaa SRRH |
7709 | if (iter->cpu_file == RING_BUFFER_ALL_CPUS) |
7710 | tracing_reset_online_cpus(&tr->max_buffer); | |
7711 | else | |
a47b53e9 | 7712 | tracing_reset_cpu(&tr->max_buffer, iter->cpu_file); |
f1affcaa | 7713 | } |
debdd57f HT |
7714 | break; |
7715 | } | |
7716 | ||
7717 | if (ret >= 0) { | |
7718 | *ppos += cnt; | |
7719 | ret = cnt; | |
7720 | } | |
7721 | out: | |
7722 | mutex_unlock(&trace_types_lock); | |
7723 | return ret; | |
7724 | } | |
2b6080f2 SR |
7725 | |
7726 | static int tracing_snapshot_release(struct inode *inode, struct file *file) | |
7727 | { | |
7728 | struct seq_file *m = file->private_data; | |
ff451961 SRRH |
7729 | int ret; |
7730 | ||
7731 | ret = tracing_release(inode, file); | |
2b6080f2 SR |
7732 | |
7733 | if (file->f_mode & FMODE_READ) | |
ff451961 | 7734 | return ret; |
2b6080f2 SR |
7735 | |
7736 | /* If write only, the seq_file is just a stub */ | |
7737 | if (m) | |
7738 | kfree(m->private); | |
7739 | kfree(m); | |
7740 | ||
7741 | return 0; | |
7742 | } | |
7743 | ||
6de58e62 SRRH |
7744 | static int tracing_buffers_open(struct inode *inode, struct file *filp); |
7745 | static ssize_t tracing_buffers_read(struct file *filp, char __user *ubuf, | |
7746 | size_t count, loff_t *ppos); | |
7747 | static int tracing_buffers_release(struct inode *inode, struct file *file); | |
7748 | static ssize_t tracing_buffers_splice_read(struct file *file, loff_t *ppos, | |
7749 | struct pipe_inode_info *pipe, size_t len, unsigned int flags); | |
7750 | ||
7751 | static int snapshot_raw_open(struct inode *inode, struct file *filp) | |
7752 | { | |
7753 | struct ftrace_buffer_info *info; | |
7754 | int ret; | |
7755 | ||
17911ff3 | 7756 | /* The following checks for tracefs lockdown */ |
6de58e62 SRRH |
7757 | ret = tracing_buffers_open(inode, filp); |
7758 | if (ret < 0) | |
7759 | return ret; | |
7760 | ||
7761 | info = filp->private_data; | |
7762 | ||
7763 | if (info->iter.trace->use_max_tr) { | |
7764 | tracing_buffers_release(inode, filp); | |
7765 | return -EBUSY; | |
7766 | } | |
7767 | ||
7768 | info->iter.snapshot = true; | |
1c5eb448 | 7769 | info->iter.array_buffer = &info->iter.tr->max_buffer; |
6de58e62 SRRH |
7770 | |
7771 | return ret; | |
7772 | } | |
7773 | ||
debdd57f HT |
7774 | #endif /* CONFIG_TRACER_SNAPSHOT */ |
7775 | ||
7776 | ||
6508fa76 SF |
7777 | static const struct file_operations tracing_thresh_fops = { |
7778 | .open = tracing_open_generic, | |
7779 | .read = tracing_thresh_read, | |
7780 | .write = tracing_thresh_write, | |
7781 | .llseek = generic_file_llseek, | |
7782 | }; | |
7783 | ||
e25e43a4 | 7784 | #ifdef CONFIG_TRACER_MAX_TRACE |
5e2336a0 | 7785 | static const struct file_operations tracing_max_lat_fops = { |
7d660c9b | 7786 | .open = tracing_open_generic_tr, |
4bf39a94 IM |
7787 | .read = tracing_max_lat_read, |
7788 | .write = tracing_max_lat_write, | |
b444786f | 7789 | .llseek = generic_file_llseek, |
7d660c9b | 7790 | .release = tracing_release_generic_tr, |
bc0c38d1 | 7791 | }; |
e428abbb | 7792 | #endif |
bc0c38d1 | 7793 | |
5e2336a0 | 7794 | static const struct file_operations set_tracer_fops = { |
9b37febc | 7795 | .open = tracing_open_generic_tr, |
4bf39a94 IM |
7796 | .read = tracing_set_trace_read, |
7797 | .write = tracing_set_trace_write, | |
b444786f | 7798 | .llseek = generic_file_llseek, |
9b37febc | 7799 | .release = tracing_release_generic_tr, |
bc0c38d1 SR |
7800 | }; |
7801 | ||
5e2336a0 | 7802 | static const struct file_operations tracing_pipe_fops = { |
4bf39a94 | 7803 | .open = tracing_open_pipe, |
2a2cc8f7 | 7804 | .poll = tracing_poll_pipe, |
4bf39a94 | 7805 | .read = tracing_read_pipe, |
3c56819b | 7806 | .splice_read = tracing_splice_read_pipe, |
4bf39a94 | 7807 | .release = tracing_release_pipe, |
b444786f | 7808 | .llseek = no_llseek, |
b3806b43 SR |
7809 | }; |
7810 | ||
5e2336a0 | 7811 | static const struct file_operations tracing_entries_fops = { |
0bc392ee | 7812 | .open = tracing_open_generic_tr, |
a98a3c3f SR |
7813 | .read = tracing_entries_read, |
7814 | .write = tracing_entries_write, | |
b444786f | 7815 | .llseek = generic_file_llseek, |
0bc392ee | 7816 | .release = tracing_release_generic_tr, |
a98a3c3f SR |
7817 | }; |
7818 | ||
f81ab074 | 7819 | static const struct file_operations tracing_total_entries_fops = { |
7b85af63 | 7820 | .open = tracing_open_generic_tr, |
f81ab074 VN |
7821 | .read = tracing_total_entries_read, |
7822 | .llseek = generic_file_llseek, | |
7b85af63 | 7823 | .release = tracing_release_generic_tr, |
f81ab074 VN |
7824 | }; |
7825 | ||
4f271a2a | 7826 | static const struct file_operations tracing_free_buffer_fops = { |
7b85af63 | 7827 | .open = tracing_open_generic_tr, |
4f271a2a VN |
7828 | .write = tracing_free_buffer_write, |
7829 | .release = tracing_free_buffer_release, | |
7830 | }; | |
7831 | ||
5e2336a0 | 7832 | static const struct file_operations tracing_mark_fops = { |
2972e305 | 7833 | .open = tracing_mark_open, |
5bf9a1ee | 7834 | .write = tracing_mark_write, |
7b85af63 | 7835 | .release = tracing_release_generic_tr, |
5bf9a1ee PP |
7836 | }; |
7837 | ||
fa32e855 | 7838 | static const struct file_operations tracing_mark_raw_fops = { |
2972e305 | 7839 | .open = tracing_mark_open, |
fa32e855 | 7840 | .write = tracing_mark_raw_write, |
fa32e855 SR |
7841 | .release = tracing_release_generic_tr, |
7842 | }; | |
7843 | ||
5079f326 | 7844 | static const struct file_operations trace_clock_fops = { |
13f16d20 LZ |
7845 | .open = tracing_clock_open, |
7846 | .read = seq_read, | |
7847 | .llseek = seq_lseek, | |
7b85af63 | 7848 | .release = tracing_single_release_tr, |
5079f326 Z |
7849 | .write = tracing_clock_write, |
7850 | }; | |
7851 | ||
2c1ea60b TZ |
7852 | static const struct file_operations trace_time_stamp_mode_fops = { |
7853 | .open = tracing_time_stamp_mode_open, | |
7854 | .read = seq_read, | |
7855 | .llseek = seq_lseek, | |
7856 | .release = tracing_single_release_tr, | |
7857 | }; | |
7858 | ||
debdd57f HT |
7859 | #ifdef CONFIG_TRACER_SNAPSHOT |
7860 | static const struct file_operations snapshot_fops = { | |
7861 | .open = tracing_snapshot_open, | |
7862 | .read = seq_read, | |
7863 | .write = tracing_snapshot_write, | |
098c879e | 7864 | .llseek = tracing_lseek, |
2b6080f2 | 7865 | .release = tracing_snapshot_release, |
debdd57f | 7866 | }; |
debdd57f | 7867 | |
6de58e62 SRRH |
7868 | static const struct file_operations snapshot_raw_fops = { |
7869 | .open = snapshot_raw_open, | |
7870 | .read = tracing_buffers_read, | |
7871 | .release = tracing_buffers_release, | |
7872 | .splice_read = tracing_buffers_splice_read, | |
7873 | .llseek = no_llseek, | |
2cadf913 SR |
7874 | }; |
7875 | ||
6de58e62 SRRH |
7876 | #endif /* CONFIG_TRACER_SNAPSHOT */ |
7877 | ||
bc87cf0a DBO |
7878 | /* |
7879 | * trace_min_max_write - Write a u64 value to a trace_min_max_param struct | |
7880 | * @filp: The active open file structure | |
7881 | * @ubuf: The userspace provided buffer to read value into | |
7882 | * @cnt: The maximum number of bytes to read | |
7883 | * @ppos: The current "file" position | |
7884 | * | |
7885 | * This function implements the write interface for a struct trace_min_max_param. | |
7886 | * The filp->private_data must point to a trace_min_max_param structure that | |
7887 | * defines where to write the value, the min and the max acceptable values, | |
7888 | * and a lock to protect the write. | |
7889 | */ | |
7890 | static ssize_t | |
7891 | trace_min_max_write(struct file *filp, const char __user *ubuf, size_t cnt, loff_t *ppos) | |
7892 | { | |
7893 | struct trace_min_max_param *param = filp->private_data; | |
7894 | u64 val; | |
7895 | int err; | |
7896 | ||
7897 | if (!param) | |
7898 | return -EFAULT; | |
7899 | ||
7900 | err = kstrtoull_from_user(ubuf, cnt, 10, &val); | |
7901 | if (err) | |
7902 | return err; | |
7903 | ||
7904 | if (param->lock) | |
7905 | mutex_lock(param->lock); | |
7906 | ||
7907 | if (param->min && val < *param->min) | |
7908 | err = -EINVAL; | |
7909 | ||
7910 | if (param->max && val > *param->max) | |
7911 | err = -EINVAL; | |
7912 | ||
7913 | if (!err) | |
7914 | *param->val = val; | |
7915 | ||
7916 | if (param->lock) | |
7917 | mutex_unlock(param->lock); | |
7918 | ||
7919 | if (err) | |
7920 | return err; | |
7921 | ||
7922 | return cnt; | |
7923 | } | |
7924 | ||
7925 | /* | |
7926 | * trace_min_max_read - Read a u64 value from a trace_min_max_param struct | |
7927 | * @filp: The active open file structure | |
7928 | * @ubuf: The userspace provided buffer to read value into | |
7929 | * @cnt: The maximum number of bytes to read | |
7930 | * @ppos: The current "file" position | |
7931 | * | |
7932 | * This function implements the read interface for a struct trace_min_max_param. | |
7933 | * The filp->private_data must point to a trace_min_max_param struct with valid | |
7934 | * data. | |
7935 | */ | |
7936 | static ssize_t | |
7937 | trace_min_max_read(struct file *filp, char __user *ubuf, size_t cnt, loff_t *ppos) | |
7938 | { | |
7939 | struct trace_min_max_param *param = filp->private_data; | |
7940 | char buf[U64_STR_SIZE]; | |
7941 | int len; | |
7942 | u64 val; | |
7943 | ||
7944 | if (!param) | |
7945 | return -EFAULT; | |
7946 | ||
7947 | val = *param->val; | |
7948 | ||
7949 | if (cnt > sizeof(buf)) | |
7950 | cnt = sizeof(buf); | |
7951 | ||
7952 | len = snprintf(buf, sizeof(buf), "%llu\n", val); | |
7953 | ||
7954 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, len); | |
7955 | } | |
7956 | ||
7957 | const struct file_operations trace_min_max_fops = { | |
7958 | .open = tracing_open_generic, | |
7959 | .read = trace_min_max_read, | |
7960 | .write = trace_min_max_write, | |
7961 | }; | |
7962 | ||
8a062902 TZ |
7963 | #define TRACING_LOG_ERRS_MAX 8 |
7964 | #define TRACING_LOG_LOC_MAX 128 | |
7965 | ||
7966 | #define CMD_PREFIX " Command: " | |
7967 | ||
7968 | struct err_info { | |
7969 | const char **errs; /* ptr to loc-specific array of err strings */ | |
7970 | u8 type; /* index into errs -> specific err string */ | |
1581a884 | 7971 | u16 pos; /* caret position */ |
8a062902 TZ |
7972 | u64 ts; |
7973 | }; | |
7974 | ||
7975 | struct tracing_log_err { | |
7976 | struct list_head list; | |
7977 | struct err_info info; | |
7978 | char loc[TRACING_LOG_LOC_MAX]; /* err location */ | |
1581a884 | 7979 | char *cmd; /* what caused err */ |
8a062902 TZ |
7980 | }; |
7981 | ||
8a062902 TZ |
7982 | static DEFINE_MUTEX(tracing_err_log_lock); |
7983 | ||
1581a884 TZ |
7984 | static struct tracing_log_err *alloc_tracing_log_err(int len) |
7985 | { | |
7986 | struct tracing_log_err *err; | |
7987 | ||
7988 | err = kzalloc(sizeof(*err), GFP_KERNEL); | |
7989 | if (!err) | |
7990 | return ERR_PTR(-ENOMEM); | |
7991 | ||
7992 | err->cmd = kzalloc(len, GFP_KERNEL); | |
7993 | if (!err->cmd) { | |
7994 | kfree(err); | |
7995 | return ERR_PTR(-ENOMEM); | |
7996 | } | |
7997 | ||
7998 | return err; | |
7999 | } | |
8000 | ||
8001 | static void free_tracing_log_err(struct tracing_log_err *err) | |
8002 | { | |
8003 | kfree(err->cmd); | |
8004 | kfree(err); | |
8005 | } | |
8006 | ||
8007 | static struct tracing_log_err *get_tracing_log_err(struct trace_array *tr, | |
8008 | int len) | |
8a062902 TZ |
8009 | { |
8010 | struct tracing_log_err *err; | |
067df9e0 | 8011 | char *cmd; |
8a062902 | 8012 | |
2f754e77 | 8013 | if (tr->n_err_log_entries < TRACING_LOG_ERRS_MAX) { |
1581a884 TZ |
8014 | err = alloc_tracing_log_err(len); |
8015 | if (PTR_ERR(err) != -ENOMEM) | |
67ab5eb7 | 8016 | tr->n_err_log_entries++; |
8a062902 TZ |
8017 | |
8018 | return err; | |
8019 | } | |
067df9e0 ZY |
8020 | cmd = kzalloc(len, GFP_KERNEL); |
8021 | if (!cmd) | |
8022 | return ERR_PTR(-ENOMEM); | |
2f754e77 | 8023 | err = list_first_entry(&tr->err_log, struct tracing_log_err, list); |
1581a884 | 8024 | kfree(err->cmd); |
067df9e0 | 8025 | err->cmd = cmd; |
8a062902 TZ |
8026 | list_del(&err->list); |
8027 | ||
8028 | return err; | |
8029 | } | |
8030 | ||
8031 | /** | |
8032 | * err_pos - find the position of a string within a command for error careting | |
8033 | * @cmd: The tracing command that caused the error | |
8034 | * @str: The string to position the caret at within @cmd | |
8035 | * | |
f2cc020d | 8036 | * Finds the position of the first occurrence of @str within @cmd. The |
8a062902 TZ |
8037 | * return value can be passed to tracing_log_err() for caret placement |
8038 | * within @cmd. | |
8039 | * | |
f2cc020d | 8040 | * Returns the index within @cmd of the first occurrence of @str or 0 |
8a062902 TZ |
8041 | * if @str was not found. |
8042 | */ | |
8043 | unsigned int err_pos(char *cmd, const char *str) | |
8044 | { | |
8045 | char *found; | |
8046 | ||
8047 | if (WARN_ON(!strlen(cmd))) | |
8048 | return 0; | |
8049 | ||
8050 | found = strstr(cmd, str); | |
8051 | if (found) | |
8052 | return found - cmd; | |
8053 | ||
8054 | return 0; | |
8055 | } | |
8056 | ||
8057 | /** | |
8058 | * tracing_log_err - write an error to the tracing error log | |
2f754e77 | 8059 | * @tr: The associated trace array for the error (NULL for top level array) |
8a062902 TZ |
8060 | * @loc: A string describing where the error occurred |
8061 | * @cmd: The tracing command that caused the error | |
8062 | * @errs: The array of loc-specific static error strings | |
8063 | * @type: The index into errs[], which produces the specific static err string | |
8064 | * @pos: The position the caret should be placed in the cmd | |
8065 | * | |
8066 | * Writes an error into tracing/error_log of the form: | |
8067 | * | |
8068 | * <loc>: error: <text> | |
8069 | * Command: <cmd> | |
8070 | * ^ | |
8071 | * | |
8072 | * tracing/error_log is a small log file containing the last | |
8073 | * TRACING_LOG_ERRS_MAX errors (8). Memory for errors isn't allocated | |
8074 | * unless there has been a tracing error, and the error log can be | |
8075 | * cleared and have its memory freed by writing the empty string in | |
8076 | * truncation mode to it i.e. echo > tracing/error_log. | |
8077 | * | |
8078 | * NOTE: the @errs array along with the @type param are used to | |
8079 | * produce a static error string - this string is not copied and saved | |
8080 | * when the error is logged - only a pointer to it is saved. See | |
8081 | * existing callers for examples of how static strings are typically | |
8082 | * defined for use with tracing_log_err(). | |
8083 | */ | |
2f754e77 SRV |
8084 | void tracing_log_err(struct trace_array *tr, |
8085 | const char *loc, const char *cmd, | |
1581a884 | 8086 | const char **errs, u8 type, u16 pos) |
8a062902 TZ |
8087 | { |
8088 | struct tracing_log_err *err; | |
1581a884 | 8089 | int len = 0; |
8a062902 | 8090 | |
2f754e77 SRV |
8091 | if (!tr) |
8092 | tr = &global_trace; | |
8093 | ||
1581a884 TZ |
8094 | len += sizeof(CMD_PREFIX) + 2 * sizeof("\n") + strlen(cmd) + 1; |
8095 | ||
8a062902 | 8096 | mutex_lock(&tracing_err_log_lock); |
1581a884 | 8097 | err = get_tracing_log_err(tr, len); |
8a062902 TZ |
8098 | if (PTR_ERR(err) == -ENOMEM) { |
8099 | mutex_unlock(&tracing_err_log_lock); | |
8100 | return; | |
8101 | } | |
8102 | ||
8103 | snprintf(err->loc, TRACING_LOG_LOC_MAX, "%s: error: ", loc); | |
1581a884 | 8104 | snprintf(err->cmd, len, "\n" CMD_PREFIX "%s\n", cmd); |
8a062902 TZ |
8105 | |
8106 | err->info.errs = errs; | |
8107 | err->info.type = type; | |
8108 | err->info.pos = pos; | |
8109 | err->info.ts = local_clock(); | |
8110 | ||
2f754e77 | 8111 | list_add_tail(&err->list, &tr->err_log); |
8a062902 TZ |
8112 | mutex_unlock(&tracing_err_log_lock); |
8113 | } | |
8114 | ||
2f754e77 | 8115 | static void clear_tracing_err_log(struct trace_array *tr) |
8a062902 TZ |
8116 | { |
8117 | struct tracing_log_err *err, *next; | |
8118 | ||
8119 | mutex_lock(&tracing_err_log_lock); | |
2f754e77 | 8120 | list_for_each_entry_safe(err, next, &tr->err_log, list) { |
8a062902 | 8121 | list_del(&err->list); |
1581a884 | 8122 | free_tracing_log_err(err); |
8a062902 TZ |
8123 | } |
8124 | ||
2f754e77 | 8125 | tr->n_err_log_entries = 0; |
8a062902 TZ |
8126 | mutex_unlock(&tracing_err_log_lock); |
8127 | } | |
8128 | ||
8129 | static void *tracing_err_log_seq_start(struct seq_file *m, loff_t *pos) | |
8130 | { | |
2f754e77 SRV |
8131 | struct trace_array *tr = m->private; |
8132 | ||
8a062902 TZ |
8133 | mutex_lock(&tracing_err_log_lock); |
8134 | ||
2f754e77 | 8135 | return seq_list_start(&tr->err_log, *pos); |
8a062902 TZ |
8136 | } |
8137 | ||
8138 | static void *tracing_err_log_seq_next(struct seq_file *m, void *v, loff_t *pos) | |
8139 | { | |
2f754e77 SRV |
8140 | struct trace_array *tr = m->private; |
8141 | ||
8142 | return seq_list_next(v, &tr->err_log, pos); | |
8a062902 TZ |
8143 | } |
8144 | ||
8145 | static void tracing_err_log_seq_stop(struct seq_file *m, void *v) | |
8146 | { | |
8147 | mutex_unlock(&tracing_err_log_lock); | |
8148 | } | |
8149 | ||
1581a884 | 8150 | static void tracing_err_log_show_pos(struct seq_file *m, u16 pos) |
8a062902 | 8151 | { |
1581a884 | 8152 | u16 i; |
8a062902 TZ |
8153 | |
8154 | for (i = 0; i < sizeof(CMD_PREFIX) - 1; i++) | |
8155 | seq_putc(m, ' '); | |
8156 | for (i = 0; i < pos; i++) | |
8157 | seq_putc(m, ' '); | |
8158 | seq_puts(m, "^\n"); | |
8159 | } | |
8160 | ||
8161 | static int tracing_err_log_seq_show(struct seq_file *m, void *v) | |
8162 | { | |
8163 | struct tracing_log_err *err = v; | |
8164 | ||
8165 | if (err) { | |
8166 | const char *err_text = err->info.errs[err->info.type]; | |
8167 | u64 sec = err->info.ts; | |
8168 | u32 nsec; | |
8169 | ||
8170 | nsec = do_div(sec, NSEC_PER_SEC); | |
8171 | seq_printf(m, "[%5llu.%06u] %s%s", sec, nsec / 1000, | |
8172 | err->loc, err_text); | |
8173 | seq_printf(m, "%s", err->cmd); | |
8174 | tracing_err_log_show_pos(m, err->info.pos); | |
8175 | } | |
8176 | ||
8177 | return 0; | |
8178 | } | |
8179 | ||
8180 | static const struct seq_operations tracing_err_log_seq_ops = { | |
8181 | .start = tracing_err_log_seq_start, | |
8182 | .next = tracing_err_log_seq_next, | |
8183 | .stop = tracing_err_log_seq_stop, | |
8184 | .show = tracing_err_log_seq_show | |
8185 | }; | |
8186 | ||
8187 | static int tracing_err_log_open(struct inode *inode, struct file *file) | |
8188 | { | |
2f754e77 | 8189 | struct trace_array *tr = inode->i_private; |
8a062902 TZ |
8190 | int ret = 0; |
8191 | ||
8530dec6 SRV |
8192 | ret = tracing_check_open_get_tr(tr); |
8193 | if (ret) | |
8194 | return ret; | |
2f754e77 | 8195 | |
8a062902 TZ |
8196 | /* If this file was opened for write, then erase contents */ |
8197 | if ((file->f_mode & FMODE_WRITE) && (file->f_flags & O_TRUNC)) | |
2f754e77 | 8198 | clear_tracing_err_log(tr); |
8a062902 | 8199 | |
2f754e77 | 8200 | if (file->f_mode & FMODE_READ) { |
8a062902 | 8201 | ret = seq_open(file, &tracing_err_log_seq_ops); |
2f754e77 SRV |
8202 | if (!ret) { |
8203 | struct seq_file *m = file->private_data; | |
8204 | m->private = tr; | |
8205 | } else { | |
8206 | trace_array_put(tr); | |
8207 | } | |
8208 | } | |
8a062902 TZ |
8209 | return ret; |
8210 | } | |
8211 | ||
8212 | static ssize_t tracing_err_log_write(struct file *file, | |
8213 | const char __user *buffer, | |
8214 | size_t count, loff_t *ppos) | |
8215 | { | |
8216 | return count; | |
8217 | } | |
8218 | ||
d122ed62 TM |
8219 | static int tracing_err_log_release(struct inode *inode, struct file *file) |
8220 | { | |
8221 | struct trace_array *tr = inode->i_private; | |
8222 | ||
8223 | trace_array_put(tr); | |
8224 | ||
8225 | if (file->f_mode & FMODE_READ) | |
8226 | seq_release(inode, file); | |
8227 | ||
8228 | return 0; | |
8229 | } | |
8230 | ||
8a062902 TZ |
8231 | static const struct file_operations tracing_err_log_fops = { |
8232 | .open = tracing_err_log_open, | |
8233 | .write = tracing_err_log_write, | |
8234 | .read = seq_read, | |
02b0095e | 8235 | .llseek = tracing_lseek, |
d122ed62 | 8236 | .release = tracing_err_log_release, |
8a062902 TZ |
8237 | }; |
8238 | ||
2cadf913 SR |
8239 | static int tracing_buffers_open(struct inode *inode, struct file *filp) |
8240 | { | |
46ef2be0 | 8241 | struct trace_array *tr = inode->i_private; |
2cadf913 | 8242 | struct ftrace_buffer_info *info; |
7b85af63 | 8243 | int ret; |
2cadf913 | 8244 | |
8530dec6 SRV |
8245 | ret = tracing_check_open_get_tr(tr); |
8246 | if (ret) | |
8247 | return ret; | |
7b85af63 | 8248 | |
0f69dae4 | 8249 | info = kvzalloc(sizeof(*info), GFP_KERNEL); |
7b85af63 SRRH |
8250 | if (!info) { |
8251 | trace_array_put(tr); | |
2cadf913 | 8252 | return -ENOMEM; |
7b85af63 | 8253 | } |
2cadf913 | 8254 | |
a695cb58 SRRH |
8255 | mutex_lock(&trace_types_lock); |
8256 | ||
cc60cdc9 | 8257 | info->iter.tr = tr; |
46ef2be0 | 8258 | info->iter.cpu_file = tracing_get_cpu(inode); |
b627344f | 8259 | info->iter.trace = tr->current_trace; |
1c5eb448 | 8260 | info->iter.array_buffer = &tr->array_buffer; |
cc60cdc9 | 8261 | info->spare = NULL; |
2cadf913 | 8262 | /* Force reading ring buffer for first read */ |
cc60cdc9 | 8263 | info->read = (unsigned int)-1; |
2cadf913 SR |
8264 | |
8265 | filp->private_data = info; | |
8266 | ||
7ef282e0 | 8267 | tr->trace_ref++; |
cf6ab6d9 | 8268 | |
a695cb58 SRRH |
8269 | mutex_unlock(&trace_types_lock); |
8270 | ||
7b85af63 SRRH |
8271 | ret = nonseekable_open(inode, filp); |
8272 | if (ret < 0) | |
8273 | trace_array_put(tr); | |
8274 | ||
8275 | return ret; | |
2cadf913 SR |
8276 | } |
8277 | ||
9dd95748 | 8278 | static __poll_t |
cc60cdc9 SR |
8279 | tracing_buffers_poll(struct file *filp, poll_table *poll_table) |
8280 | { | |
8281 | struct ftrace_buffer_info *info = filp->private_data; | |
8282 | struct trace_iterator *iter = &info->iter; | |
8283 | ||
8284 | return trace_poll(iter, filp, poll_table); | |
8285 | } | |
8286 | ||
2cadf913 SR |
8287 | static ssize_t |
8288 | tracing_buffers_read(struct file *filp, char __user *ubuf, | |
8289 | size_t count, loff_t *ppos) | |
8290 | { | |
8291 | struct ftrace_buffer_info *info = filp->private_data; | |
cc60cdc9 | 8292 | struct trace_iterator *iter = &info->iter; |
a7e52ad7 | 8293 | ssize_t ret = 0; |
6de58e62 | 8294 | ssize_t size; |
2cadf913 | 8295 | |
2dc5d12b SR |
8296 | if (!count) |
8297 | return 0; | |
8298 | ||
6de58e62 | 8299 | #ifdef CONFIG_TRACER_MAX_TRACE |
d716ff71 SRRH |
8300 | if (iter->snapshot && iter->tr->current_trace->use_max_tr) |
8301 | return -EBUSY; | |
6de58e62 SRRH |
8302 | #endif |
8303 | ||
73a757e6 | 8304 | if (!info->spare) { |
1c5eb448 | 8305 | info->spare = ring_buffer_alloc_read_page(iter->array_buffer->buffer, |
12883efb | 8306 | iter->cpu_file); |
a7e52ad7 SRV |
8307 | if (IS_ERR(info->spare)) { |
8308 | ret = PTR_ERR(info->spare); | |
8309 | info->spare = NULL; | |
8310 | } else { | |
8311 | info->spare_cpu = iter->cpu_file; | |
8312 | } | |
73a757e6 | 8313 | } |
ddd538f3 | 8314 | if (!info->spare) |
a7e52ad7 | 8315 | return ret; |
ddd538f3 | 8316 | |
2cadf913 SR |
8317 | /* Do we have previous read data to read? */ |
8318 | if (info->read < PAGE_SIZE) | |
8319 | goto read; | |
8320 | ||
b627344f | 8321 | again: |
cc60cdc9 | 8322 | trace_access_lock(iter->cpu_file); |
1c5eb448 | 8323 | ret = ring_buffer_read_page(iter->array_buffer->buffer, |
2cadf913 SR |
8324 | &info->spare, |
8325 | count, | |
cc60cdc9 SR |
8326 | iter->cpu_file, 0); |
8327 | trace_access_unlock(iter->cpu_file); | |
2cadf913 | 8328 | |
b627344f SR |
8329 | if (ret < 0) { |
8330 | if (trace_empty(iter)) { | |
d716ff71 SRRH |
8331 | if ((filp->f_flags & O_NONBLOCK)) |
8332 | return -EAGAIN; | |
8333 | ||
2c2b0a78 | 8334 | ret = wait_on_pipe(iter, 0); |
d716ff71 SRRH |
8335 | if (ret) |
8336 | return ret; | |
8337 | ||
b627344f SR |
8338 | goto again; |
8339 | } | |
d716ff71 | 8340 | return 0; |
b627344f | 8341 | } |
436fc280 | 8342 | |
436fc280 | 8343 | info->read = 0; |
b627344f | 8344 | read: |
2cadf913 SR |
8345 | size = PAGE_SIZE - info->read; |
8346 | if (size > count) | |
8347 | size = count; | |
8348 | ||
8349 | ret = copy_to_user(ubuf, info->spare + info->read, size); | |
d716ff71 SRRH |
8350 | if (ret == size) |
8351 | return -EFAULT; | |
8352 | ||
2dc5d12b SR |
8353 | size -= ret; |
8354 | ||
2cadf913 SR |
8355 | *ppos += size; |
8356 | info->read += size; | |
8357 | ||
8358 | return size; | |
8359 | } | |
8360 | ||
8361 | static int tracing_buffers_release(struct inode *inode, struct file *file) | |
8362 | { | |
8363 | struct ftrace_buffer_info *info = file->private_data; | |
cc60cdc9 | 8364 | struct trace_iterator *iter = &info->iter; |
2cadf913 | 8365 | |
a695cb58 SRRH |
8366 | mutex_lock(&trace_types_lock); |
8367 | ||
7ef282e0 | 8368 | iter->tr->trace_ref--; |
cf6ab6d9 | 8369 | |
ff451961 | 8370 | __trace_array_put(iter->tr); |
2cadf913 | 8371 | |
f3ddb74a SRG |
8372 | iter->wait_index++; |
8373 | /* Make sure the waiters see the new wait_index */ | |
8374 | smp_wmb(); | |
8375 | ||
8376 | ring_buffer_wake_waiters(iter->array_buffer->buffer, iter->cpu_file); | |
8377 | ||
ddd538f3 | 8378 | if (info->spare) |
1c5eb448 | 8379 | ring_buffer_free_read_page(iter->array_buffer->buffer, |
73a757e6 | 8380 | info->spare_cpu, info->spare); |
0f69dae4 | 8381 | kvfree(info); |
2cadf913 | 8382 | |
a695cb58 SRRH |
8383 | mutex_unlock(&trace_types_lock); |
8384 | ||
2cadf913 SR |
8385 | return 0; |
8386 | } | |
8387 | ||
8388 | struct buffer_ref { | |
13292494 | 8389 | struct trace_buffer *buffer; |
2cadf913 | 8390 | void *page; |
73a757e6 | 8391 | int cpu; |
b9872226 | 8392 | refcount_t refcount; |
2cadf913 SR |
8393 | }; |
8394 | ||
b9872226 JH |
8395 | static void buffer_ref_release(struct buffer_ref *ref) |
8396 | { | |
8397 | if (!refcount_dec_and_test(&ref->refcount)) | |
8398 | return; | |
8399 | ring_buffer_free_read_page(ref->buffer, ref->cpu, ref->page); | |
8400 | kfree(ref); | |
8401 | } | |
8402 | ||
2cadf913 SR |
8403 | static void buffer_pipe_buf_release(struct pipe_inode_info *pipe, |
8404 | struct pipe_buffer *buf) | |
8405 | { | |
8406 | struct buffer_ref *ref = (struct buffer_ref *)buf->private; | |
8407 | ||
b9872226 | 8408 | buffer_ref_release(ref); |
2cadf913 SR |
8409 | buf->private = 0; |
8410 | } | |
8411 | ||
15fab63e | 8412 | static bool buffer_pipe_buf_get(struct pipe_inode_info *pipe, |
2cadf913 SR |
8413 | struct pipe_buffer *buf) |
8414 | { | |
8415 | struct buffer_ref *ref = (struct buffer_ref *)buf->private; | |
8416 | ||
e9e1a2e7 | 8417 | if (refcount_read(&ref->refcount) > INT_MAX/2) |
15fab63e MW |
8418 | return false; |
8419 | ||
b9872226 | 8420 | refcount_inc(&ref->refcount); |
15fab63e | 8421 | return true; |
2cadf913 SR |
8422 | } |
8423 | ||
8424 | /* Pipe buffer operations for a buffer. */ | |
28dfef8f | 8425 | static const struct pipe_buf_operations buffer_pipe_buf_ops = { |
2cadf913 | 8426 | .release = buffer_pipe_buf_release, |
2cadf913 SR |
8427 | .get = buffer_pipe_buf_get, |
8428 | }; | |
8429 | ||
8430 | /* | |
8431 | * Callback from splice_to_pipe(), if we need to release some pages | |
8432 | * at the end of the spd in case we error'ed out in filling the pipe. | |
8433 | */ | |
8434 | static void buffer_spd_release(struct splice_pipe_desc *spd, unsigned int i) | |
8435 | { | |
8436 | struct buffer_ref *ref = | |
8437 | (struct buffer_ref *)spd->partial[i].private; | |
8438 | ||
b9872226 | 8439 | buffer_ref_release(ref); |
2cadf913 SR |
8440 | spd->partial[i].private = 0; |
8441 | } | |
8442 | ||
8443 | static ssize_t | |
8444 | tracing_buffers_splice_read(struct file *file, loff_t *ppos, | |
8445 | struct pipe_inode_info *pipe, size_t len, | |
8446 | unsigned int flags) | |
8447 | { | |
8448 | struct ftrace_buffer_info *info = file->private_data; | |
cc60cdc9 | 8449 | struct trace_iterator *iter = &info->iter; |
35f3d14d JA |
8450 | struct partial_page partial_def[PIPE_DEF_BUFFERS]; |
8451 | struct page *pages_def[PIPE_DEF_BUFFERS]; | |
2cadf913 | 8452 | struct splice_pipe_desc spd = { |
35f3d14d JA |
8453 | .pages = pages_def, |
8454 | .partial = partial_def, | |
047fe360 | 8455 | .nr_pages_max = PIPE_DEF_BUFFERS, |
2cadf913 SR |
8456 | .ops = &buffer_pipe_buf_ops, |
8457 | .spd_release = buffer_spd_release, | |
8458 | }; | |
8459 | struct buffer_ref *ref; | |
6b7e633f | 8460 | int entries, i; |
07906da7 | 8461 | ssize_t ret = 0; |
2cadf913 | 8462 | |
6de58e62 | 8463 | #ifdef CONFIG_TRACER_MAX_TRACE |
d716ff71 SRRH |
8464 | if (iter->snapshot && iter->tr->current_trace->use_max_tr) |
8465 | return -EBUSY; | |
6de58e62 SRRH |
8466 | #endif |
8467 | ||
d716ff71 SRRH |
8468 | if (*ppos & (PAGE_SIZE - 1)) |
8469 | return -EINVAL; | |
93cfb3c9 LJ |
8470 | |
8471 | if (len & (PAGE_SIZE - 1)) { | |
d716ff71 SRRH |
8472 | if (len < PAGE_SIZE) |
8473 | return -EINVAL; | |
93cfb3c9 LJ |
8474 | len &= PAGE_MASK; |
8475 | } | |
8476 | ||
1ae2293d AV |
8477 | if (splice_grow_spd(pipe, &spd)) |
8478 | return -ENOMEM; | |
8479 | ||
cc60cdc9 SR |
8480 | again: |
8481 | trace_access_lock(iter->cpu_file); | |
1c5eb448 | 8482 | entries = ring_buffer_entries_cpu(iter->array_buffer->buffer, iter->cpu_file); |
93459c6c | 8483 | |
a786c06d | 8484 | for (i = 0; i < spd.nr_pages_max && len && entries; i++, len -= PAGE_SIZE) { |
2cadf913 SR |
8485 | struct page *page; |
8486 | int r; | |
8487 | ||
8488 | ref = kzalloc(sizeof(*ref), GFP_KERNEL); | |
07906da7 RV |
8489 | if (!ref) { |
8490 | ret = -ENOMEM; | |
2cadf913 | 8491 | break; |
07906da7 | 8492 | } |
2cadf913 | 8493 | |
b9872226 | 8494 | refcount_set(&ref->refcount, 1); |
1c5eb448 | 8495 | ref->buffer = iter->array_buffer->buffer; |
cc60cdc9 | 8496 | ref->page = ring_buffer_alloc_read_page(ref->buffer, iter->cpu_file); |
a7e52ad7 SRV |
8497 | if (IS_ERR(ref->page)) { |
8498 | ret = PTR_ERR(ref->page); | |
8499 | ref->page = NULL; | |
2cadf913 SR |
8500 | kfree(ref); |
8501 | break; | |
8502 | } | |
73a757e6 | 8503 | ref->cpu = iter->cpu_file; |
2cadf913 SR |
8504 | |
8505 | r = ring_buffer_read_page(ref->buffer, &ref->page, | |
cc60cdc9 | 8506 | len, iter->cpu_file, 1); |
2cadf913 | 8507 | if (r < 0) { |
73a757e6 SRV |
8508 | ring_buffer_free_read_page(ref->buffer, ref->cpu, |
8509 | ref->page); | |
2cadf913 SR |
8510 | kfree(ref); |
8511 | break; | |
8512 | } | |
8513 | ||
2cadf913 SR |
8514 | page = virt_to_page(ref->page); |
8515 | ||
8516 | spd.pages[i] = page; | |
8517 | spd.partial[i].len = PAGE_SIZE; | |
8518 | spd.partial[i].offset = 0; | |
8519 | spd.partial[i].private = (unsigned long)ref; | |
8520 | spd.nr_pages++; | |
93cfb3c9 | 8521 | *ppos += PAGE_SIZE; |
93459c6c | 8522 | |
1c5eb448 | 8523 | entries = ring_buffer_entries_cpu(iter->array_buffer->buffer, iter->cpu_file); |
2cadf913 SR |
8524 | } |
8525 | ||
cc60cdc9 | 8526 | trace_access_unlock(iter->cpu_file); |
2cadf913 SR |
8527 | spd.nr_pages = i; |
8528 | ||
8529 | /* did we read anything? */ | |
8530 | if (!spd.nr_pages) { | |
f3ddb74a SRG |
8531 | long wait_index; |
8532 | ||
07906da7 | 8533 | if (ret) |
1ae2293d | 8534 | goto out; |
d716ff71 | 8535 | |
1ae2293d | 8536 | ret = -EAGAIN; |
d716ff71 | 8537 | if ((file->f_flags & O_NONBLOCK) || (flags & SPLICE_F_NONBLOCK)) |
1ae2293d | 8538 | goto out; |
07906da7 | 8539 | |
f3ddb74a SRG |
8540 | wait_index = READ_ONCE(iter->wait_index); |
8541 | ||
03329f99 | 8542 | ret = wait_on_pipe(iter, iter->tr->buffer_percent); |
8b8b3683 | 8543 | if (ret) |
1ae2293d | 8544 | goto out; |
e30f53aa | 8545 | |
2b0fd9a5 SRG |
8546 | /* No need to wait after waking up when tracing is off */ |
8547 | if (!tracer_tracing_is_on(iter->tr)) | |
8548 | goto out; | |
8549 | ||
f3ddb74a SRG |
8550 | /* Make sure we see the new wait_index */ |
8551 | smp_rmb(); | |
8552 | if (wait_index != iter->wait_index) | |
8553 | goto out; | |
8554 | ||
cc60cdc9 | 8555 | goto again; |
2cadf913 SR |
8556 | } |
8557 | ||
8558 | ret = splice_to_pipe(pipe, &spd); | |
1ae2293d | 8559 | out: |
047fe360 | 8560 | splice_shrink_spd(&spd); |
6de58e62 | 8561 | |
2cadf913 SR |
8562 | return ret; |
8563 | } | |
8564 | ||
01b2a521 SRG |
8565 | /* An ioctl call with cmd 0 to the ring buffer file will wake up all waiters */ |
8566 | static long tracing_buffers_ioctl(struct file *file, unsigned int cmd, unsigned long arg) | |
8567 | { | |
8568 | struct ftrace_buffer_info *info = file->private_data; | |
8569 | struct trace_iterator *iter = &info->iter; | |
8570 | ||
8571 | if (cmd) | |
8572 | return -ENOIOCTLCMD; | |
8573 | ||
8574 | mutex_lock(&trace_types_lock); | |
8575 | ||
8576 | iter->wait_index++; | |
8577 | /* Make sure the waiters see the new wait_index */ | |
8578 | smp_wmb(); | |
8579 | ||
8580 | ring_buffer_wake_waiters(iter->array_buffer->buffer, iter->cpu_file); | |
8581 | ||
8582 | mutex_unlock(&trace_types_lock); | |
8583 | return 0; | |
8584 | } | |
8585 | ||
2cadf913 SR |
8586 | static const struct file_operations tracing_buffers_fops = { |
8587 | .open = tracing_buffers_open, | |
8588 | .read = tracing_buffers_read, | |
cc60cdc9 | 8589 | .poll = tracing_buffers_poll, |
2cadf913 SR |
8590 | .release = tracing_buffers_release, |
8591 | .splice_read = tracing_buffers_splice_read, | |
01b2a521 | 8592 | .unlocked_ioctl = tracing_buffers_ioctl, |
2cadf913 SR |
8593 | .llseek = no_llseek, |
8594 | }; | |
8595 | ||
c8d77183 SR |
8596 | static ssize_t |
8597 | tracing_stats_read(struct file *filp, char __user *ubuf, | |
8598 | size_t count, loff_t *ppos) | |
8599 | { | |
4d3435b8 ON |
8600 | struct inode *inode = file_inode(filp); |
8601 | struct trace_array *tr = inode->i_private; | |
1c5eb448 | 8602 | struct array_buffer *trace_buf = &tr->array_buffer; |
4d3435b8 | 8603 | int cpu = tracing_get_cpu(inode); |
c8d77183 SR |
8604 | struct trace_seq *s; |
8605 | unsigned long cnt; | |
c64e148a VN |
8606 | unsigned long long t; |
8607 | unsigned long usec_rem; | |
c8d77183 | 8608 | |
e4f2d10f | 8609 | s = kmalloc(sizeof(*s), GFP_KERNEL); |
c8d77183 | 8610 | if (!s) |
a646365c | 8611 | return -ENOMEM; |
c8d77183 SR |
8612 | |
8613 | trace_seq_init(s); | |
8614 | ||
12883efb | 8615 | cnt = ring_buffer_entries_cpu(trace_buf->buffer, cpu); |
c8d77183 SR |
8616 | trace_seq_printf(s, "entries: %ld\n", cnt); |
8617 | ||
12883efb | 8618 | cnt = ring_buffer_overrun_cpu(trace_buf->buffer, cpu); |
c8d77183 SR |
8619 | trace_seq_printf(s, "overrun: %ld\n", cnt); |
8620 | ||
12883efb | 8621 | cnt = ring_buffer_commit_overrun_cpu(trace_buf->buffer, cpu); |
c8d77183 SR |
8622 | trace_seq_printf(s, "commit overrun: %ld\n", cnt); |
8623 | ||
12883efb | 8624 | cnt = ring_buffer_bytes_cpu(trace_buf->buffer, cpu); |
c64e148a VN |
8625 | trace_seq_printf(s, "bytes: %ld\n", cnt); |
8626 | ||
58e8eedf | 8627 | if (trace_clocks[tr->clock_id].in_ns) { |
11043d8b | 8628 | /* local or global for trace_clock */ |
12883efb | 8629 | t = ns2usecs(ring_buffer_oldest_event_ts(trace_buf->buffer, cpu)); |
11043d8b YY |
8630 | usec_rem = do_div(t, USEC_PER_SEC); |
8631 | trace_seq_printf(s, "oldest event ts: %5llu.%06lu\n", | |
8632 | t, usec_rem); | |
8633 | ||
f3ef7202 | 8634 | t = ns2usecs(ring_buffer_time_stamp(trace_buf->buffer)); |
11043d8b YY |
8635 | usec_rem = do_div(t, USEC_PER_SEC); |
8636 | trace_seq_printf(s, "now ts: %5llu.%06lu\n", t, usec_rem); | |
8637 | } else { | |
8638 | /* counter or tsc mode for trace_clock */ | |
8639 | trace_seq_printf(s, "oldest event ts: %llu\n", | |
12883efb | 8640 | ring_buffer_oldest_event_ts(trace_buf->buffer, cpu)); |
c64e148a | 8641 | |
11043d8b | 8642 | trace_seq_printf(s, "now ts: %llu\n", |
f3ef7202 | 8643 | ring_buffer_time_stamp(trace_buf->buffer)); |
11043d8b | 8644 | } |
c64e148a | 8645 | |
12883efb | 8646 | cnt = ring_buffer_dropped_events_cpu(trace_buf->buffer, cpu); |
884bfe89 SP |
8647 | trace_seq_printf(s, "dropped events: %ld\n", cnt); |
8648 | ||
12883efb | 8649 | cnt = ring_buffer_read_events_cpu(trace_buf->buffer, cpu); |
ad964704 SRRH |
8650 | trace_seq_printf(s, "read events: %ld\n", cnt); |
8651 | ||
5ac48378 SRRH |
8652 | count = simple_read_from_buffer(ubuf, count, ppos, |
8653 | s->buffer, trace_seq_used(s)); | |
c8d77183 SR |
8654 | |
8655 | kfree(s); | |
8656 | ||
8657 | return count; | |
8658 | } | |
8659 | ||
8660 | static const struct file_operations tracing_stats_fops = { | |
4d3435b8 | 8661 | .open = tracing_open_generic_tr, |
c8d77183 | 8662 | .read = tracing_stats_read, |
b444786f | 8663 | .llseek = generic_file_llseek, |
4d3435b8 | 8664 | .release = tracing_release_generic_tr, |
c8d77183 SR |
8665 | }; |
8666 | ||
bc0c38d1 SR |
8667 | #ifdef CONFIG_DYNAMIC_FTRACE |
8668 | ||
8669 | static ssize_t | |
b807c3d0 | 8670 | tracing_read_dyn_info(struct file *filp, char __user *ubuf, |
bc0c38d1 SR |
8671 | size_t cnt, loff_t *ppos) |
8672 | { | |
da537f0a SRV |
8673 | ssize_t ret; |
8674 | char *buf; | |
bc0c38d1 SR |
8675 | int r; |
8676 | ||
da537f0a SRV |
8677 | /* 256 should be plenty to hold the amount needed */ |
8678 | buf = kmalloc(256, GFP_KERNEL); | |
8679 | if (!buf) | |
8680 | return -ENOMEM; | |
b807c3d0 | 8681 | |
da537f0a SRV |
8682 | r = scnprintf(buf, 256, "%ld pages:%ld groups: %ld\n", |
8683 | ftrace_update_tot_cnt, | |
8684 | ftrace_number_of_pages, | |
8685 | ftrace_number_of_groups); | |
8686 | ||
8687 | ret = simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
8688 | kfree(buf); | |
8689 | return ret; | |
bc0c38d1 SR |
8690 | } |
8691 | ||
5e2336a0 | 8692 | static const struct file_operations tracing_dyn_info_fops = { |
4bf39a94 | 8693 | .open = tracing_open_generic, |
b807c3d0 | 8694 | .read = tracing_read_dyn_info, |
b444786f | 8695 | .llseek = generic_file_llseek, |
bc0c38d1 | 8696 | }; |
77fd5c15 | 8697 | #endif /* CONFIG_DYNAMIC_FTRACE */ |
bc0c38d1 | 8698 | |
77fd5c15 SRRH |
8699 | #if defined(CONFIG_TRACER_SNAPSHOT) && defined(CONFIG_DYNAMIC_FTRACE) |
8700 | static void | |
bca6c8d0 | 8701 | ftrace_snapshot(unsigned long ip, unsigned long parent_ip, |
b5f081b5 | 8702 | struct trace_array *tr, struct ftrace_probe_ops *ops, |
6e444319 | 8703 | void *data) |
77fd5c15 | 8704 | { |
cab50379 | 8705 | tracing_snapshot_instance(tr); |
77fd5c15 | 8706 | } |
bc0c38d1 | 8707 | |
77fd5c15 | 8708 | static void |
bca6c8d0 | 8709 | ftrace_count_snapshot(unsigned long ip, unsigned long parent_ip, |
b5f081b5 | 8710 | struct trace_array *tr, struct ftrace_probe_ops *ops, |
6e444319 | 8711 | void *data) |
bc0c38d1 | 8712 | { |
6e444319 | 8713 | struct ftrace_func_mapper *mapper = data; |
1a93f8bd | 8714 | long *count = NULL; |
77fd5c15 | 8715 | |
1a93f8bd SRV |
8716 | if (mapper) |
8717 | count = (long *)ftrace_func_mapper_find_ip(mapper, ip); | |
8718 | ||
8719 | if (count) { | |
8720 | ||
8721 | if (*count <= 0) | |
8722 | return; | |
bc0c38d1 | 8723 | |
77fd5c15 | 8724 | (*count)--; |
1a93f8bd | 8725 | } |
77fd5c15 | 8726 | |
cab50379 | 8727 | tracing_snapshot_instance(tr); |
77fd5c15 SRRH |
8728 | } |
8729 | ||
8730 | static int | |
8731 | ftrace_snapshot_print(struct seq_file *m, unsigned long ip, | |
8732 | struct ftrace_probe_ops *ops, void *data) | |
8733 | { | |
6e444319 | 8734 | struct ftrace_func_mapper *mapper = data; |
1a93f8bd | 8735 | long *count = NULL; |
77fd5c15 SRRH |
8736 | |
8737 | seq_printf(m, "%ps:", (void *)ip); | |
8738 | ||
fa6f0cc7 | 8739 | seq_puts(m, "snapshot"); |
77fd5c15 | 8740 | |
1a93f8bd SRV |
8741 | if (mapper) |
8742 | count = (long *)ftrace_func_mapper_find_ip(mapper, ip); | |
8743 | ||
8744 | if (count) | |
8745 | seq_printf(m, ":count=%ld\n", *count); | |
77fd5c15 | 8746 | else |
1a93f8bd | 8747 | seq_puts(m, ":unlimited\n"); |
77fd5c15 SRRH |
8748 | |
8749 | return 0; | |
8750 | } | |
8751 | ||
1a93f8bd | 8752 | static int |
b5f081b5 | 8753 | ftrace_snapshot_init(struct ftrace_probe_ops *ops, struct trace_array *tr, |
6e444319 | 8754 | unsigned long ip, void *init_data, void **data) |
1a93f8bd | 8755 | { |
6e444319 SRV |
8756 | struct ftrace_func_mapper *mapper = *data; |
8757 | ||
8758 | if (!mapper) { | |
8759 | mapper = allocate_ftrace_func_mapper(); | |
8760 | if (!mapper) | |
8761 | return -ENOMEM; | |
8762 | *data = mapper; | |
8763 | } | |
1a93f8bd | 8764 | |
6e444319 | 8765 | return ftrace_func_mapper_add_ip(mapper, ip, init_data); |
1a93f8bd SRV |
8766 | } |
8767 | ||
8768 | static void | |
b5f081b5 | 8769 | ftrace_snapshot_free(struct ftrace_probe_ops *ops, struct trace_array *tr, |
6e444319 | 8770 | unsigned long ip, void *data) |
1a93f8bd | 8771 | { |
6e444319 SRV |
8772 | struct ftrace_func_mapper *mapper = data; |
8773 | ||
8774 | if (!ip) { | |
8775 | if (!mapper) | |
8776 | return; | |
8777 | free_ftrace_func_mapper(mapper, NULL); | |
8778 | return; | |
8779 | } | |
1a93f8bd SRV |
8780 | |
8781 | ftrace_func_mapper_remove_ip(mapper, ip); | |
8782 | } | |
8783 | ||
77fd5c15 SRRH |
8784 | static struct ftrace_probe_ops snapshot_probe_ops = { |
8785 | .func = ftrace_snapshot, | |
8786 | .print = ftrace_snapshot_print, | |
8787 | }; | |
8788 | ||
8789 | static struct ftrace_probe_ops snapshot_count_probe_ops = { | |
8790 | .func = ftrace_count_snapshot, | |
8791 | .print = ftrace_snapshot_print, | |
1a93f8bd SRV |
8792 | .init = ftrace_snapshot_init, |
8793 | .free = ftrace_snapshot_free, | |
77fd5c15 SRRH |
8794 | }; |
8795 | ||
8796 | static int | |
04ec7bb6 | 8797 | ftrace_trace_snapshot_callback(struct trace_array *tr, struct ftrace_hash *hash, |
77fd5c15 SRRH |
8798 | char *glob, char *cmd, char *param, int enable) |
8799 | { | |
8800 | struct ftrace_probe_ops *ops; | |
8801 | void *count = (void *)-1; | |
8802 | char *number; | |
8803 | int ret; | |
8804 | ||
0f179765 SRV |
8805 | if (!tr) |
8806 | return -ENODEV; | |
8807 | ||
77fd5c15 SRRH |
8808 | /* hash funcs only work with set_ftrace_filter */ |
8809 | if (!enable) | |
8810 | return -EINVAL; | |
8811 | ||
8812 | ops = param ? &snapshot_count_probe_ops : &snapshot_probe_ops; | |
8813 | ||
d3d532d7 | 8814 | if (glob[0] == '!') |
7b60f3d8 | 8815 | return unregister_ftrace_function_probe_func(glob+1, tr, ops); |
77fd5c15 SRRH |
8816 | |
8817 | if (!param) | |
8818 | goto out_reg; | |
8819 | ||
8820 | number = strsep(¶m, ":"); | |
8821 | ||
8822 | if (!strlen(number)) | |
8823 | goto out_reg; | |
8824 | ||
8825 | /* | |
8826 | * We use the callback data field (which is a pointer) | |
8827 | * as our counter. | |
8828 | */ | |
8829 | ret = kstrtoul(number, 0, (unsigned long *)&count); | |
8830 | if (ret) | |
8831 | return ret; | |
8832 | ||
8833 | out_reg: | |
2824f503 | 8834 | ret = tracing_alloc_snapshot_instance(tr); |
df62db5b SRV |
8835 | if (ret < 0) |
8836 | goto out; | |
77fd5c15 | 8837 | |
4c174688 | 8838 | ret = register_ftrace_function_probe(glob, tr, ops, count); |
77fd5c15 | 8839 | |
df62db5b | 8840 | out: |
77fd5c15 SRRH |
8841 | return ret < 0 ? ret : 0; |
8842 | } | |
8843 | ||
8844 | static struct ftrace_func_command ftrace_snapshot_cmd = { | |
8845 | .name = "snapshot", | |
8846 | .func = ftrace_trace_snapshot_callback, | |
8847 | }; | |
8848 | ||
38de93ab | 8849 | static __init int register_snapshot_cmd(void) |
77fd5c15 SRRH |
8850 | { |
8851 | return register_ftrace_command(&ftrace_snapshot_cmd); | |
8852 | } | |
8853 | #else | |
38de93ab | 8854 | static inline __init int register_snapshot_cmd(void) { return 0; } |
77fd5c15 | 8855 | #endif /* defined(CONFIG_TRACER_SNAPSHOT) && defined(CONFIG_DYNAMIC_FTRACE) */ |
bc0c38d1 | 8856 | |
7eeafbca | 8857 | static struct dentry *tracing_get_dentry(struct trace_array *tr) |
bc0c38d1 | 8858 | { |
8434dc93 SRRH |
8859 | if (WARN_ON(!tr->dir)) |
8860 | return ERR_PTR(-ENODEV); | |
8861 | ||
8862 | /* Top directory uses NULL as the parent */ | |
8863 | if (tr->flags & TRACE_ARRAY_FL_GLOBAL) | |
8864 | return NULL; | |
8865 | ||
8866 | /* All sub buffers have a descriptor */ | |
2b6080f2 | 8867 | return tr->dir; |
bc0c38d1 SR |
8868 | } |
8869 | ||
2b6080f2 | 8870 | static struct dentry *tracing_dentry_percpu(struct trace_array *tr, int cpu) |
b04cc6b1 | 8871 | { |
b04cc6b1 FW |
8872 | struct dentry *d_tracer; |
8873 | ||
2b6080f2 SR |
8874 | if (tr->percpu_dir) |
8875 | return tr->percpu_dir; | |
b04cc6b1 | 8876 | |
7eeafbca | 8877 | d_tracer = tracing_get_dentry(tr); |
14a5ae40 | 8878 | if (IS_ERR(d_tracer)) |
b04cc6b1 FW |
8879 | return NULL; |
8880 | ||
8434dc93 | 8881 | tr->percpu_dir = tracefs_create_dir("per_cpu", d_tracer); |
b04cc6b1 | 8882 | |
24589e3a | 8883 | MEM_FAIL(!tr->percpu_dir, |
8434dc93 | 8884 | "Could not create tracefs directory 'per_cpu/%d'\n", cpu); |
b04cc6b1 | 8885 | |
2b6080f2 | 8886 | return tr->percpu_dir; |
b04cc6b1 FW |
8887 | } |
8888 | ||
649e9c70 ON |
8889 | static struct dentry * |
8890 | trace_create_cpu_file(const char *name, umode_t mode, struct dentry *parent, | |
8891 | void *data, long cpu, const struct file_operations *fops) | |
8892 | { | |
8893 | struct dentry *ret = trace_create_file(name, mode, parent, data, fops); | |
8894 | ||
8895 | if (ret) /* See tracing_get_cpu() */ | |
7682c918 | 8896 | d_inode(ret)->i_cdev = (void *)(cpu + 1); |
649e9c70 ON |
8897 | return ret; |
8898 | } | |
8899 | ||
2b6080f2 | 8900 | static void |
8434dc93 | 8901 | tracing_init_tracefs_percpu(struct trace_array *tr, long cpu) |
b04cc6b1 | 8902 | { |
2b6080f2 | 8903 | struct dentry *d_percpu = tracing_dentry_percpu(tr, cpu); |
5452af66 | 8904 | struct dentry *d_cpu; |
dd49a38c | 8905 | char cpu_dir[30]; /* 30 characters should be more than enough */ |
b04cc6b1 | 8906 | |
0a3d7ce7 NK |
8907 | if (!d_percpu) |
8908 | return; | |
8909 | ||
dd49a38c | 8910 | snprintf(cpu_dir, 30, "cpu%ld", cpu); |
8434dc93 | 8911 | d_cpu = tracefs_create_dir(cpu_dir, d_percpu); |
8656e7a2 | 8912 | if (!d_cpu) { |
a395d6a7 | 8913 | pr_warn("Could not create tracefs '%s' entry\n", cpu_dir); |
8656e7a2 FW |
8914 | return; |
8915 | } | |
b04cc6b1 | 8916 | |
8656e7a2 | 8917 | /* per cpu trace_pipe */ |
21ccc9cd | 8918 | trace_create_cpu_file("trace_pipe", TRACE_MODE_READ, d_cpu, |
15544209 | 8919 | tr, cpu, &tracing_pipe_fops); |
b04cc6b1 FW |
8920 | |
8921 | /* per cpu trace */ | |
21ccc9cd | 8922 | trace_create_cpu_file("trace", TRACE_MODE_WRITE, d_cpu, |
6484c71c | 8923 | tr, cpu, &tracing_fops); |
7f96f93f | 8924 | |
21ccc9cd | 8925 | trace_create_cpu_file("trace_pipe_raw", TRACE_MODE_READ, d_cpu, |
46ef2be0 | 8926 | tr, cpu, &tracing_buffers_fops); |
7f96f93f | 8927 | |
21ccc9cd | 8928 | trace_create_cpu_file("stats", TRACE_MODE_READ, d_cpu, |
4d3435b8 | 8929 | tr, cpu, &tracing_stats_fops); |
438ced17 | 8930 | |
21ccc9cd | 8931 | trace_create_cpu_file("buffer_size_kb", TRACE_MODE_READ, d_cpu, |
0bc392ee | 8932 | tr, cpu, &tracing_entries_fops); |
f1affcaa SRRH |
8933 | |
8934 | #ifdef CONFIG_TRACER_SNAPSHOT | |
21ccc9cd | 8935 | trace_create_cpu_file("snapshot", TRACE_MODE_WRITE, d_cpu, |
6484c71c | 8936 | tr, cpu, &snapshot_fops); |
6de58e62 | 8937 | |
21ccc9cd | 8938 | trace_create_cpu_file("snapshot_raw", TRACE_MODE_READ, d_cpu, |
46ef2be0 | 8939 | tr, cpu, &snapshot_raw_fops); |
f1affcaa | 8940 | #endif |
b04cc6b1 FW |
8941 | } |
8942 | ||
60a11774 SR |
8943 | #ifdef CONFIG_FTRACE_SELFTEST |
8944 | /* Let selftest have access to static functions in this file */ | |
8945 | #include "trace_selftest.c" | |
8946 | #endif | |
8947 | ||
577b785f SR |
8948 | static ssize_t |
8949 | trace_options_read(struct file *filp, char __user *ubuf, size_t cnt, | |
8950 | loff_t *ppos) | |
8951 | { | |
8952 | struct trace_option_dentry *topt = filp->private_data; | |
8953 | char *buf; | |
8954 | ||
8955 | if (topt->flags->val & topt->opt->bit) | |
8956 | buf = "1\n"; | |
8957 | else | |
8958 | buf = "0\n"; | |
8959 | ||
8960 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, 2); | |
8961 | } | |
8962 | ||
8963 | static ssize_t | |
8964 | trace_options_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
8965 | loff_t *ppos) | |
8966 | { | |
8967 | struct trace_option_dentry *topt = filp->private_data; | |
8968 | unsigned long val; | |
577b785f SR |
8969 | int ret; |
8970 | ||
22fe9b54 PH |
8971 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
8972 | if (ret) | |
577b785f SR |
8973 | return ret; |
8974 | ||
8d18eaaf LZ |
8975 | if (val != 0 && val != 1) |
8976 | return -EINVAL; | |
577b785f | 8977 | |
8d18eaaf | 8978 | if (!!(topt->flags->val & topt->opt->bit) != val) { |
577b785f | 8979 | mutex_lock(&trace_types_lock); |
8c1a49ae | 8980 | ret = __set_tracer_option(topt->tr, topt->flags, |
c757bea9 | 8981 | topt->opt, !val); |
577b785f SR |
8982 | mutex_unlock(&trace_types_lock); |
8983 | if (ret) | |
8984 | return ret; | |
577b785f SR |
8985 | } |
8986 | ||
8987 | *ppos += cnt; | |
8988 | ||
8989 | return cnt; | |
8990 | } | |
8991 | ||
7e2cfbd2 SRG |
8992 | static int tracing_open_options(struct inode *inode, struct file *filp) |
8993 | { | |
8994 | struct trace_option_dentry *topt = inode->i_private; | |
8995 | int ret; | |
8996 | ||
8997 | ret = tracing_check_open_get_tr(topt->tr); | |
8998 | if (ret) | |
8999 | return ret; | |
9000 | ||
9001 | filp->private_data = inode->i_private; | |
9002 | return 0; | |
9003 | } | |
9004 | ||
9005 | static int tracing_release_options(struct inode *inode, struct file *file) | |
9006 | { | |
9007 | struct trace_option_dentry *topt = file->private_data; | |
9008 | ||
9009 | trace_array_put(topt->tr); | |
9010 | return 0; | |
9011 | } | |
577b785f SR |
9012 | |
9013 | static const struct file_operations trace_options_fops = { | |
7e2cfbd2 | 9014 | .open = tracing_open_options, |
577b785f SR |
9015 | .read = trace_options_read, |
9016 | .write = trace_options_write, | |
b444786f | 9017 | .llseek = generic_file_llseek, |
7e2cfbd2 | 9018 | .release = tracing_release_options, |
577b785f SR |
9019 | }; |
9020 | ||
9a38a885 SRRH |
9021 | /* |
9022 | * In order to pass in both the trace_array descriptor as well as the index | |
9023 | * to the flag that the trace option file represents, the trace_array | |
9024 | * has a character array of trace_flags_index[], which holds the index | |
9025 | * of the bit for the flag it represents. index[0] == 0, index[1] == 1, etc. | |
9026 | * The address of this character array is passed to the flag option file | |
9027 | * read/write callbacks. | |
9028 | * | |
9029 | * In order to extract both the index and the trace_array descriptor, | |
9030 | * get_tr_index() uses the following algorithm. | |
9031 | * | |
9032 | * idx = *ptr; | |
9033 | * | |
9034 | * As the pointer itself contains the address of the index (remember | |
9035 | * index[1] == 1). | |
9036 | * | |
9037 | * Then to get the trace_array descriptor, by subtracting that index | |
9038 | * from the ptr, we get to the start of the index itself. | |
9039 | * | |
9040 | * ptr - idx == &index[0] | |
9041 | * | |
9042 | * Then a simple container_of() from that pointer gets us to the | |
9043 | * trace_array descriptor. | |
9044 | */ | |
9045 | static void get_tr_index(void *data, struct trace_array **ptr, | |
9046 | unsigned int *pindex) | |
9047 | { | |
9048 | *pindex = *(unsigned char *)data; | |
9049 | ||
9050 | *ptr = container_of(data - *pindex, struct trace_array, | |
9051 | trace_flags_index); | |
9052 | } | |
9053 | ||
a8259075 SR |
9054 | static ssize_t |
9055 | trace_options_core_read(struct file *filp, char __user *ubuf, size_t cnt, | |
9056 | loff_t *ppos) | |
9057 | { | |
9a38a885 SRRH |
9058 | void *tr_index = filp->private_data; |
9059 | struct trace_array *tr; | |
9060 | unsigned int index; | |
a8259075 SR |
9061 | char *buf; |
9062 | ||
9a38a885 SRRH |
9063 | get_tr_index(tr_index, &tr, &index); |
9064 | ||
9065 | if (tr->trace_flags & (1 << index)) | |
a8259075 SR |
9066 | buf = "1\n"; |
9067 | else | |
9068 | buf = "0\n"; | |
9069 | ||
9070 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, 2); | |
9071 | } | |
9072 | ||
9073 | static ssize_t | |
9074 | trace_options_core_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
9075 | loff_t *ppos) | |
9076 | { | |
9a38a885 SRRH |
9077 | void *tr_index = filp->private_data; |
9078 | struct trace_array *tr; | |
9079 | unsigned int index; | |
a8259075 SR |
9080 | unsigned long val; |
9081 | int ret; | |
9082 | ||
9a38a885 SRRH |
9083 | get_tr_index(tr_index, &tr, &index); |
9084 | ||
22fe9b54 PH |
9085 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
9086 | if (ret) | |
a8259075 SR |
9087 | return ret; |
9088 | ||
f2d84b65 | 9089 | if (val != 0 && val != 1) |
a8259075 | 9090 | return -EINVAL; |
69d34da2 | 9091 | |
3a53acf1 | 9092 | mutex_lock(&event_mutex); |
69d34da2 | 9093 | mutex_lock(&trace_types_lock); |
2b6080f2 | 9094 | ret = set_tracer_flag(tr, 1 << index, val); |
69d34da2 | 9095 | mutex_unlock(&trace_types_lock); |
3a53acf1 | 9096 | mutex_unlock(&event_mutex); |
a8259075 | 9097 | |
613f04a0 SRRH |
9098 | if (ret < 0) |
9099 | return ret; | |
9100 | ||
a8259075 SR |
9101 | *ppos += cnt; |
9102 | ||
9103 | return cnt; | |
9104 | } | |
9105 | ||
a8259075 SR |
9106 | static const struct file_operations trace_options_core_fops = { |
9107 | .open = tracing_open_generic, | |
9108 | .read = trace_options_core_read, | |
9109 | .write = trace_options_core_write, | |
b444786f | 9110 | .llseek = generic_file_llseek, |
a8259075 SR |
9111 | }; |
9112 | ||
5452af66 | 9113 | struct dentry *trace_create_file(const char *name, |
f4ae40a6 | 9114 | umode_t mode, |
5452af66 FW |
9115 | struct dentry *parent, |
9116 | void *data, | |
9117 | const struct file_operations *fops) | |
9118 | { | |
9119 | struct dentry *ret; | |
9120 | ||
8434dc93 | 9121 | ret = tracefs_create_file(name, mode, parent, data, fops); |
5452af66 | 9122 | if (!ret) |
a395d6a7 | 9123 | pr_warn("Could not create tracefs '%s' entry\n", name); |
5452af66 FW |
9124 | |
9125 | return ret; | |
9126 | } | |
9127 | ||
9128 | ||
2b6080f2 | 9129 | static struct dentry *trace_options_init_dentry(struct trace_array *tr) |
a8259075 SR |
9130 | { |
9131 | struct dentry *d_tracer; | |
a8259075 | 9132 | |
2b6080f2 SR |
9133 | if (tr->options) |
9134 | return tr->options; | |
a8259075 | 9135 | |
7eeafbca | 9136 | d_tracer = tracing_get_dentry(tr); |
14a5ae40 | 9137 | if (IS_ERR(d_tracer)) |
a8259075 SR |
9138 | return NULL; |
9139 | ||
8434dc93 | 9140 | tr->options = tracefs_create_dir("options", d_tracer); |
2b6080f2 | 9141 | if (!tr->options) { |
a395d6a7 | 9142 | pr_warn("Could not create tracefs directory 'options'\n"); |
a8259075 SR |
9143 | return NULL; |
9144 | } | |
9145 | ||
2b6080f2 | 9146 | return tr->options; |
a8259075 SR |
9147 | } |
9148 | ||
577b785f | 9149 | static void |
2b6080f2 SR |
9150 | create_trace_option_file(struct trace_array *tr, |
9151 | struct trace_option_dentry *topt, | |
577b785f SR |
9152 | struct tracer_flags *flags, |
9153 | struct tracer_opt *opt) | |
9154 | { | |
9155 | struct dentry *t_options; | |
577b785f | 9156 | |
2b6080f2 | 9157 | t_options = trace_options_init_dentry(tr); |
577b785f SR |
9158 | if (!t_options) |
9159 | return; | |
9160 | ||
9161 | topt->flags = flags; | |
9162 | topt->opt = opt; | |
2b6080f2 | 9163 | topt->tr = tr; |
577b785f | 9164 | |
21ccc9cd SRV |
9165 | topt->entry = trace_create_file(opt->name, TRACE_MODE_WRITE, |
9166 | t_options, topt, &trace_options_fops); | |
577b785f | 9167 | |
577b785f SR |
9168 | } |
9169 | ||
37aea98b | 9170 | static void |
2b6080f2 | 9171 | create_trace_option_files(struct trace_array *tr, struct tracer *tracer) |
577b785f SR |
9172 | { |
9173 | struct trace_option_dentry *topts; | |
37aea98b | 9174 | struct trace_options *tr_topts; |
577b785f SR |
9175 | struct tracer_flags *flags; |
9176 | struct tracer_opt *opts; | |
9177 | int cnt; | |
37aea98b | 9178 | int i; |
577b785f SR |
9179 | |
9180 | if (!tracer) | |
37aea98b | 9181 | return; |
577b785f SR |
9182 | |
9183 | flags = tracer->flags; | |
9184 | ||
9185 | if (!flags || !flags->opts) | |
37aea98b SRRH |
9186 | return; |
9187 | ||
9188 | /* | |
9189 | * If this is an instance, only create flags for tracers | |
9190 | * the instance may have. | |
9191 | */ | |
9192 | if (!trace_ok_for_array(tracer, tr)) | |
9193 | return; | |
9194 | ||
9195 | for (i = 0; i < tr->nr_topts; i++) { | |
d39cdd20 CH |
9196 | /* Make sure there's no duplicate flags. */ |
9197 | if (WARN_ON_ONCE(tr->topts[i].tracer->flags == tracer->flags)) | |
37aea98b SRRH |
9198 | return; |
9199 | } | |
577b785f SR |
9200 | |
9201 | opts = flags->opts; | |
9202 | ||
9203 | for (cnt = 0; opts[cnt].name; cnt++) | |
9204 | ; | |
9205 | ||
0cfe8245 | 9206 | topts = kcalloc(cnt + 1, sizeof(*topts), GFP_KERNEL); |
577b785f | 9207 | if (!topts) |
37aea98b SRRH |
9208 | return; |
9209 | ||
9210 | tr_topts = krealloc(tr->topts, sizeof(*tr->topts) * (tr->nr_topts + 1), | |
9211 | GFP_KERNEL); | |
9212 | if (!tr_topts) { | |
9213 | kfree(topts); | |
9214 | return; | |
9215 | } | |
9216 | ||
9217 | tr->topts = tr_topts; | |
9218 | tr->topts[tr->nr_topts].tracer = tracer; | |
9219 | tr->topts[tr->nr_topts].topts = topts; | |
9220 | tr->nr_topts++; | |
577b785f | 9221 | |
41d9c0be | 9222 | for (cnt = 0; opts[cnt].name; cnt++) { |
2b6080f2 | 9223 | create_trace_option_file(tr, &topts[cnt], flags, |
577b785f | 9224 | &opts[cnt]); |
24589e3a | 9225 | MEM_FAIL(topts[cnt].entry == NULL, |
41d9c0be SRRH |
9226 | "Failed to create trace option: %s", |
9227 | opts[cnt].name); | |
9228 | } | |
577b785f SR |
9229 | } |
9230 | ||
a8259075 | 9231 | static struct dentry * |
2b6080f2 SR |
9232 | create_trace_option_core_file(struct trace_array *tr, |
9233 | const char *option, long index) | |
a8259075 SR |
9234 | { |
9235 | struct dentry *t_options; | |
a8259075 | 9236 | |
2b6080f2 | 9237 | t_options = trace_options_init_dentry(tr); |
a8259075 SR |
9238 | if (!t_options) |
9239 | return NULL; | |
9240 | ||
21ccc9cd | 9241 | return trace_create_file(option, TRACE_MODE_WRITE, t_options, |
9a38a885 SRRH |
9242 | (void *)&tr->trace_flags_index[index], |
9243 | &trace_options_core_fops); | |
a8259075 SR |
9244 | } |
9245 | ||
16270145 | 9246 | static void create_trace_options_dir(struct trace_array *tr) |
a8259075 SR |
9247 | { |
9248 | struct dentry *t_options; | |
16270145 | 9249 | bool top_level = tr == &global_trace; |
a8259075 SR |
9250 | int i; |
9251 | ||
2b6080f2 | 9252 | t_options = trace_options_init_dentry(tr); |
a8259075 SR |
9253 | if (!t_options) |
9254 | return; | |
9255 | ||
16270145 SRRH |
9256 | for (i = 0; trace_options[i]; i++) { |
9257 | if (top_level || | |
9258 | !((1 << i) & TOP_LEVEL_TRACE_FLAGS)) | |
9259 | create_trace_option_core_file(tr, trace_options[i], i); | |
9260 | } | |
a8259075 SR |
9261 | } |
9262 | ||
499e5470 SR |
9263 | static ssize_t |
9264 | rb_simple_read(struct file *filp, char __user *ubuf, | |
9265 | size_t cnt, loff_t *ppos) | |
9266 | { | |
348f0fc2 | 9267 | struct trace_array *tr = filp->private_data; |
499e5470 SR |
9268 | char buf[64]; |
9269 | int r; | |
9270 | ||
10246fa3 | 9271 | r = tracer_tracing_is_on(tr); |
499e5470 SR |
9272 | r = sprintf(buf, "%d\n", r); |
9273 | ||
9274 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
9275 | } | |
9276 | ||
9277 | static ssize_t | |
9278 | rb_simple_write(struct file *filp, const char __user *ubuf, | |
9279 | size_t cnt, loff_t *ppos) | |
9280 | { | |
348f0fc2 | 9281 | struct trace_array *tr = filp->private_data; |
13292494 | 9282 | struct trace_buffer *buffer = tr->array_buffer.buffer; |
499e5470 SR |
9283 | unsigned long val; |
9284 | int ret; | |
9285 | ||
9286 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); | |
9287 | if (ret) | |
9288 | return ret; | |
9289 | ||
9290 | if (buffer) { | |
2df8f8a6 | 9291 | mutex_lock(&trace_types_lock); |
f143641b SRV |
9292 | if (!!val == tracer_tracing_is_on(tr)) { |
9293 | val = 0; /* do nothing */ | |
9294 | } else if (val) { | |
10246fa3 | 9295 | tracer_tracing_on(tr); |
2b6080f2 SR |
9296 | if (tr->current_trace->start) |
9297 | tr->current_trace->start(tr); | |
2df8f8a6 | 9298 | } else { |
10246fa3 | 9299 | tracer_tracing_off(tr); |
2b6080f2 SR |
9300 | if (tr->current_trace->stop) |
9301 | tr->current_trace->stop(tr); | |
2b0fd9a5 SRG |
9302 | /* Wake up any waiters */ |
9303 | ring_buffer_wake_waiters(buffer, RING_BUFFER_ALL_CPUS); | |
2df8f8a6 SR |
9304 | } |
9305 | mutex_unlock(&trace_types_lock); | |
499e5470 SR |
9306 | } |
9307 | ||
9308 | (*ppos)++; | |
9309 | ||
9310 | return cnt; | |
9311 | } | |
9312 | ||
9313 | static const struct file_operations rb_simple_fops = { | |
7b85af63 | 9314 | .open = tracing_open_generic_tr, |
499e5470 SR |
9315 | .read = rb_simple_read, |
9316 | .write = rb_simple_write, | |
7b85af63 | 9317 | .release = tracing_release_generic_tr, |
499e5470 SR |
9318 | .llseek = default_llseek, |
9319 | }; | |
9320 | ||
03329f99 SRV |
9321 | static ssize_t |
9322 | buffer_percent_read(struct file *filp, char __user *ubuf, | |
9323 | size_t cnt, loff_t *ppos) | |
9324 | { | |
9325 | struct trace_array *tr = filp->private_data; | |
9326 | char buf[64]; | |
9327 | int r; | |
9328 | ||
9329 | r = tr->buffer_percent; | |
9330 | r = sprintf(buf, "%d\n", r); | |
9331 | ||
9332 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
9333 | } | |
9334 | ||
9335 | static ssize_t | |
9336 | buffer_percent_write(struct file *filp, const char __user *ubuf, | |
9337 | size_t cnt, loff_t *ppos) | |
9338 | { | |
9339 | struct trace_array *tr = filp->private_data; | |
9340 | unsigned long val; | |
9341 | int ret; | |
9342 | ||
9343 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); | |
9344 | if (ret) | |
9345 | return ret; | |
9346 | ||
9347 | if (val > 100) | |
9348 | return -EINVAL; | |
9349 | ||
03329f99 SRV |
9350 | tr->buffer_percent = val; |
9351 | ||
9352 | (*ppos)++; | |
9353 | ||
9354 | return cnt; | |
9355 | } | |
9356 | ||
9357 | static const struct file_operations buffer_percent_fops = { | |
9358 | .open = tracing_open_generic_tr, | |
9359 | .read = buffer_percent_read, | |
9360 | .write = buffer_percent_write, | |
9361 | .release = tracing_release_generic_tr, | |
9362 | .llseek = default_llseek, | |
9363 | }; | |
9364 | ||
ff585c5b | 9365 | static struct dentry *trace_instance_dir; |
277ba044 SR |
9366 | |
9367 | static void | |
8434dc93 | 9368 | init_tracer_tracefs(struct trace_array *tr, struct dentry *d_tracer); |
277ba044 | 9369 | |
55034cd6 | 9370 | static int |
1c5eb448 | 9371 | allocate_trace_buffer(struct trace_array *tr, struct array_buffer *buf, int size) |
277ba044 SR |
9372 | { |
9373 | enum ring_buffer_flags rb_flags; | |
737223fb | 9374 | |
983f938a | 9375 | rb_flags = tr->trace_flags & TRACE_ITER_OVERWRITE ? RB_FL_OVERWRITE : 0; |
737223fb | 9376 | |
dced341b SRRH |
9377 | buf->tr = tr; |
9378 | ||
55034cd6 SRRH |
9379 | buf->buffer = ring_buffer_alloc(size, rb_flags); |
9380 | if (!buf->buffer) | |
9381 | return -ENOMEM; | |
737223fb | 9382 | |
55034cd6 SRRH |
9383 | buf->data = alloc_percpu(struct trace_array_cpu); |
9384 | if (!buf->data) { | |
9385 | ring_buffer_free(buf->buffer); | |
4397f045 | 9386 | buf->buffer = NULL; |
55034cd6 SRRH |
9387 | return -ENOMEM; |
9388 | } | |
737223fb | 9389 | |
737223fb | 9390 | /* Allocate the first page for all buffers */ |
1c5eb448 SRV |
9391 | set_buffer_entries(&tr->array_buffer, |
9392 | ring_buffer_size(tr->array_buffer.buffer, 0)); | |
737223fb | 9393 | |
55034cd6 SRRH |
9394 | return 0; |
9395 | } | |
737223fb | 9396 | |
59927cbe ZL |
9397 | static void free_trace_buffer(struct array_buffer *buf) |
9398 | { | |
9399 | if (buf->buffer) { | |
9400 | ring_buffer_free(buf->buffer); | |
9401 | buf->buffer = NULL; | |
9402 | free_percpu(buf->data); | |
9403 | buf->data = NULL; | |
9404 | } | |
9405 | } | |
9406 | ||
55034cd6 SRRH |
9407 | static int allocate_trace_buffers(struct trace_array *tr, int size) |
9408 | { | |
9409 | int ret; | |
737223fb | 9410 | |
1c5eb448 | 9411 | ret = allocate_trace_buffer(tr, &tr->array_buffer, size); |
55034cd6 SRRH |
9412 | if (ret) |
9413 | return ret; | |
737223fb | 9414 | |
55034cd6 SRRH |
9415 | #ifdef CONFIG_TRACER_MAX_TRACE |
9416 | ret = allocate_trace_buffer(tr, &tr->max_buffer, | |
9417 | allocate_snapshot ? size : 1); | |
24589e3a | 9418 | if (MEM_FAIL(ret, "Failed to allocate trace buffer\n")) { |
59927cbe | 9419 | free_trace_buffer(&tr->array_buffer); |
55034cd6 SRRH |
9420 | return -ENOMEM; |
9421 | } | |
9422 | tr->allocated_snapshot = allocate_snapshot; | |
737223fb | 9423 | |
55034cd6 | 9424 | allocate_snapshot = false; |
737223fb | 9425 | #endif |
11f5efc3 | 9426 | |
55034cd6 | 9427 | return 0; |
737223fb SRRH |
9428 | } |
9429 | ||
23aaa3c1 SRRH |
9430 | static void free_trace_buffers(struct trace_array *tr) |
9431 | { | |
9432 | if (!tr) | |
9433 | return; | |
9434 | ||
1c5eb448 | 9435 | free_trace_buffer(&tr->array_buffer); |
23aaa3c1 SRRH |
9436 | |
9437 | #ifdef CONFIG_TRACER_MAX_TRACE | |
f0b70cc4 | 9438 | free_trace_buffer(&tr->max_buffer); |
23aaa3c1 SRRH |
9439 | #endif |
9440 | } | |
9441 | ||
9a38a885 SRRH |
9442 | static void init_trace_flags_index(struct trace_array *tr) |
9443 | { | |
9444 | int i; | |
9445 | ||
9446 | /* Used by the trace options files */ | |
9447 | for (i = 0; i < TRACE_FLAGS_MAX_SIZE; i++) | |
9448 | tr->trace_flags_index[i] = i; | |
9449 | } | |
9450 | ||
37aea98b SRRH |
9451 | static void __update_tracer_options(struct trace_array *tr) |
9452 | { | |
9453 | struct tracer *t; | |
9454 | ||
9455 | for (t = trace_types; t; t = t->next) | |
9456 | add_tracer_options(tr, t); | |
9457 | } | |
9458 | ||
9459 | static void update_tracer_options(struct trace_array *tr) | |
9460 | { | |
9461 | mutex_lock(&trace_types_lock); | |
ef9188bc | 9462 | tracer_options_updated = true; |
37aea98b SRRH |
9463 | __update_tracer_options(tr); |
9464 | mutex_unlock(&trace_types_lock); | |
9465 | } | |
9466 | ||
89c95fce TZ |
9467 | /* Must have trace_types_lock held */ |
9468 | struct trace_array *trace_array_find(const char *instance) | |
9469 | { | |
9470 | struct trace_array *tr, *found = NULL; | |
9471 | ||
9472 | list_for_each_entry(tr, &ftrace_trace_arrays, list) { | |
9473 | if (tr->name && strcmp(tr->name, instance) == 0) { | |
9474 | found = tr; | |
9475 | break; | |
9476 | } | |
9477 | } | |
9478 | ||
9479 | return found; | |
9480 | } | |
9481 | ||
9482 | struct trace_array *trace_array_find_get(const char *instance) | |
9483 | { | |
9484 | struct trace_array *tr; | |
9485 | ||
9486 | mutex_lock(&trace_types_lock); | |
9487 | tr = trace_array_find(instance); | |
9488 | if (tr) | |
9489 | tr->ref++; | |
9490 | mutex_unlock(&trace_types_lock); | |
9491 | ||
9492 | return tr; | |
9493 | } | |
9494 | ||
4114fbfd MH |
9495 | static int trace_array_create_dir(struct trace_array *tr) |
9496 | { | |
9497 | int ret; | |
9498 | ||
9499 | tr->dir = tracefs_create_dir(tr->name, trace_instance_dir); | |
9500 | if (!tr->dir) | |
9501 | return -EINVAL; | |
9502 | ||
9503 | ret = event_trace_add_tracer(tr->dir, tr); | |
ff41c28c | 9504 | if (ret) { |
4114fbfd | 9505 | tracefs_remove(tr->dir); |
ff41c28c KA |
9506 | return ret; |
9507 | } | |
4114fbfd MH |
9508 | |
9509 | init_tracer_tracefs(tr, tr->dir); | |
9510 | __update_tracer_options(tr); | |
9511 | ||
9512 | return ret; | |
9513 | } | |
9514 | ||
28879787 | 9515 | static struct trace_array *trace_array_create(const char *name) |
737223fb | 9516 | { |
277ba044 SR |
9517 | struct trace_array *tr; |
9518 | int ret; | |
277ba044 | 9519 | |
277ba044 SR |
9520 | ret = -ENOMEM; |
9521 | tr = kzalloc(sizeof(*tr), GFP_KERNEL); | |
9522 | if (!tr) | |
28879787 | 9523 | return ERR_PTR(ret); |
277ba044 SR |
9524 | |
9525 | tr->name = kstrdup(name, GFP_KERNEL); | |
9526 | if (!tr->name) | |
9527 | goto out_free_tr; | |
9528 | ||
ccfe9e42 AL |
9529 | if (!alloc_cpumask_var(&tr->tracing_cpumask, GFP_KERNEL)) |
9530 | goto out_free_tr; | |
9531 | ||
3d07fa1d | 9532 | if (!zalloc_cpumask_var(&tr->pipe_cpumask, GFP_KERNEL)) |
c2489bb7 ZY |
9533 | goto out_free_tr; |
9534 | ||
20550622 | 9535 | tr->trace_flags = global_trace.trace_flags & ~ZEROED_TRACE_FLAGS; |
983f938a | 9536 | |
ccfe9e42 AL |
9537 | cpumask_copy(tr->tracing_cpumask, cpu_all_mask); |
9538 | ||
277ba044 SR |
9539 | raw_spin_lock_init(&tr->start_lock); |
9540 | ||
0b9b12c1 SRRH |
9541 | tr->max_lock = (arch_spinlock_t)__ARCH_SPIN_LOCK_UNLOCKED; |
9542 | ||
277ba044 SR |
9543 | tr->current_trace = &nop_trace; |
9544 | ||
9545 | INIT_LIST_HEAD(&tr->systems); | |
9546 | INIT_LIST_HEAD(&tr->events); | |
067fe038 | 9547 | INIT_LIST_HEAD(&tr->hist_vars); |
2f754e77 | 9548 | INIT_LIST_HEAD(&tr->err_log); |
277ba044 | 9549 | |
737223fb | 9550 | if (allocate_trace_buffers(tr, trace_buf_size) < 0) |
277ba044 SR |
9551 | goto out_free_tr; |
9552 | ||
4114fbfd | 9553 | if (ftrace_allocate_ftrace_ops(tr) < 0) |
277ba044 SR |
9554 | goto out_free_tr; |
9555 | ||
04ec7bb6 SRV |
9556 | ftrace_init_trace_array(tr); |
9557 | ||
9a38a885 | 9558 | init_trace_flags_index(tr); |
4114fbfd MH |
9559 | |
9560 | if (trace_instance_dir) { | |
9561 | ret = trace_array_create_dir(tr); | |
9562 | if (ret) | |
9563 | goto out_free_tr; | |
720dee53 MH |
9564 | } else |
9565 | __trace_early_add_events(tr); | |
277ba044 SR |
9566 | |
9567 | list_add(&tr->list, &ftrace_trace_arrays); | |
9568 | ||
28879787 DI |
9569 | tr->ref++; |
9570 | ||
f45d1225 | 9571 | return tr; |
277ba044 SR |
9572 | |
9573 | out_free_tr: | |
4114fbfd | 9574 | ftrace_free_ftrace_ops(tr); |
23aaa3c1 | 9575 | free_trace_buffers(tr); |
c2489bb7 | 9576 | free_cpumask_var(tr->pipe_cpumask); |
ccfe9e42 | 9577 | free_cpumask_var(tr->tracing_cpumask); |
277ba044 SR |
9578 | kfree(tr->name); |
9579 | kfree(tr); | |
9580 | ||
f45d1225 DI |
9581 | return ERR_PTR(ret); |
9582 | } | |
277ba044 | 9583 | |
f45d1225 DI |
9584 | static int instance_mkdir(const char *name) |
9585 | { | |
28879787 DI |
9586 | struct trace_array *tr; |
9587 | int ret; | |
9588 | ||
9589 | mutex_lock(&event_mutex); | |
9590 | mutex_lock(&trace_types_lock); | |
9591 | ||
9592 | ret = -EEXIST; | |
89c95fce TZ |
9593 | if (trace_array_find(name)) |
9594 | goto out_unlock; | |
28879787 DI |
9595 | |
9596 | tr = trace_array_create(name); | |
9597 | ||
9598 | ret = PTR_ERR_OR_ZERO(tr); | |
9599 | ||
9600 | out_unlock: | |
9601 | mutex_unlock(&trace_types_lock); | |
9602 | mutex_unlock(&event_mutex); | |
9603 | return ret; | |
9604 | } | |
9605 | ||
9606 | /** | |
9607 | * trace_array_get_by_name - Create/Lookup a trace array, given its name. | |
9608 | * @name: The name of the trace array to be looked up/created. | |
9609 | * | |
9610 | * Returns pointer to trace array with given name. | |
9611 | * NULL, if it cannot be created. | |
9612 | * | |
9613 | * NOTE: This function increments the reference counter associated with the | |
9614 | * trace array returned. This makes sure it cannot be freed while in use. | |
9615 | * Use trace_array_put() once the trace array is no longer needed. | |
28394da2 SRV |
9616 | * If the trace_array is to be freed, trace_array_destroy() needs to |
9617 | * be called after the trace_array_put(), or simply let user space delete | |
9618 | * it from the tracefs instances directory. But until the | |
9619 | * trace_array_put() is called, user space can not delete it. | |
28879787 DI |
9620 | * |
9621 | */ | |
9622 | struct trace_array *trace_array_get_by_name(const char *name) | |
9623 | { | |
9624 | struct trace_array *tr; | |
9625 | ||
9626 | mutex_lock(&event_mutex); | |
9627 | mutex_lock(&trace_types_lock); | |
9628 | ||
9629 | list_for_each_entry(tr, &ftrace_trace_arrays, list) { | |
9630 | if (tr->name && strcmp(tr->name, name) == 0) | |
9631 | goto out_unlock; | |
9632 | } | |
9633 | ||
9634 | tr = trace_array_create(name); | |
9635 | ||
9636 | if (IS_ERR(tr)) | |
9637 | tr = NULL; | |
9638 | out_unlock: | |
9639 | if (tr) | |
9640 | tr->ref++; | |
9641 | ||
9642 | mutex_unlock(&trace_types_lock); | |
9643 | mutex_unlock(&event_mutex); | |
9644 | return tr; | |
277ba044 | 9645 | } |
28879787 | 9646 | EXPORT_SYMBOL_GPL(trace_array_get_by_name); |
277ba044 | 9647 | |
f45d1225 | 9648 | static int __remove_instance(struct trace_array *tr) |
0c8916c3 | 9649 | { |
37aea98b | 9650 | int i; |
0c8916c3 | 9651 | |
28879787 | 9652 | /* Reference counter for a newly created trace array = 1. */ |
7ef282e0 | 9653 | if (tr->ref > 1 || (tr->current_trace && tr->trace_ref)) |
f45d1225 | 9654 | return -EBUSY; |
a695cb58 | 9655 | |
0c8916c3 SR |
9656 | list_del(&tr->list); |
9657 | ||
20550622 SRRH |
9658 | /* Disable all the flags that were enabled coming in */ |
9659 | for (i = 0; i < TRACE_FLAGS_MAX_SIZE; i++) { | |
9660 | if ((1 << i) & ZEROED_TRACE_FLAGS) | |
9661 | set_tracer_flag(tr, 1 << i, 0); | |
9662 | } | |
9663 | ||
6b450d25 | 9664 | tracing_set_nop(tr); |
a0e6369e | 9665 | clear_ftrace_function_probes(tr); |
0c8916c3 | 9666 | event_trace_del_tracer(tr); |
d879d0b8 | 9667 | ftrace_clear_pids(tr); |
591dffda | 9668 | ftrace_destroy_function_files(tr); |
a3d1e7eb | 9669 | tracefs_remove(tr->dir); |
20344c54 | 9670 | free_percpu(tr->last_func_repeats); |
a9fcaaac | 9671 | free_trace_buffers(tr); |
3357c6e4 | 9672 | clear_tracing_err_log(tr); |
0c8916c3 | 9673 | |
37aea98b SRRH |
9674 | for (i = 0; i < tr->nr_topts; i++) { |
9675 | kfree(tr->topts[i].topts); | |
9676 | } | |
9677 | kfree(tr->topts); | |
9678 | ||
c2489bb7 | 9679 | free_cpumask_var(tr->pipe_cpumask); |
db9108e0 | 9680 | free_cpumask_var(tr->tracing_cpumask); |
0c8916c3 SR |
9681 | kfree(tr->name); |
9682 | kfree(tr); | |
9683 | ||
f45d1225 DI |
9684 | return 0; |
9685 | } | |
9686 | ||
e585e646 | 9687 | int trace_array_destroy(struct trace_array *this_tr) |
f45d1225 | 9688 | { |
e585e646 | 9689 | struct trace_array *tr; |
f45d1225 DI |
9690 | int ret; |
9691 | ||
e585e646 | 9692 | if (!this_tr) |
f45d1225 DI |
9693 | return -EINVAL; |
9694 | ||
9695 | mutex_lock(&event_mutex); | |
9696 | mutex_lock(&trace_types_lock); | |
9697 | ||
e585e646 DI |
9698 | ret = -ENODEV; |
9699 | ||
9700 | /* Making sure trace array exists before destroying it. */ | |
9701 | list_for_each_entry(tr, &ftrace_trace_arrays, list) { | |
9702 | if (tr == this_tr) { | |
9703 | ret = __remove_instance(tr); | |
9704 | break; | |
9705 | } | |
9706 | } | |
f45d1225 DI |
9707 | |
9708 | mutex_unlock(&trace_types_lock); | |
9709 | mutex_unlock(&event_mutex); | |
9710 | ||
9711 | return ret; | |
9712 | } | |
9713 | EXPORT_SYMBOL_GPL(trace_array_destroy); | |
9714 | ||
9715 | static int instance_rmdir(const char *name) | |
9716 | { | |
9717 | struct trace_array *tr; | |
9718 | int ret; | |
9719 | ||
9720 | mutex_lock(&event_mutex); | |
9721 | mutex_lock(&trace_types_lock); | |
9722 | ||
9723 | ret = -ENODEV; | |
89c95fce TZ |
9724 | tr = trace_array_find(name); |
9725 | if (tr) | |
9726 | ret = __remove_instance(tr); | |
0c8916c3 | 9727 | |
0c8916c3 | 9728 | mutex_unlock(&trace_types_lock); |
12ecef0c | 9729 | mutex_unlock(&event_mutex); |
0c8916c3 SR |
9730 | |
9731 | return ret; | |
9732 | } | |
9733 | ||
277ba044 SR |
9734 | static __init void create_trace_instances(struct dentry *d_tracer) |
9735 | { | |
4114fbfd MH |
9736 | struct trace_array *tr; |
9737 | ||
eae47358 SRRH |
9738 | trace_instance_dir = tracefs_create_instance_dir("instances", d_tracer, |
9739 | instance_mkdir, | |
9740 | instance_rmdir); | |
24589e3a | 9741 | if (MEM_FAIL(!trace_instance_dir, "Failed to create instances directory\n")) |
277ba044 | 9742 | return; |
4114fbfd MH |
9743 | |
9744 | mutex_lock(&event_mutex); | |
9745 | mutex_lock(&trace_types_lock); | |
9746 | ||
9747 | list_for_each_entry(tr, &ftrace_trace_arrays, list) { | |
9748 | if (!tr->name) | |
9749 | continue; | |
9750 | if (MEM_FAIL(trace_array_create_dir(tr) < 0, | |
9751 | "Failed to create instance directory\n")) | |
9752 | break; | |
9753 | } | |
9754 | ||
9755 | mutex_unlock(&trace_types_lock); | |
9756 | mutex_unlock(&event_mutex); | |
277ba044 SR |
9757 | } |
9758 | ||
2b6080f2 | 9759 | static void |
8434dc93 | 9760 | init_tracer_tracefs(struct trace_array *tr, struct dentry *d_tracer) |
2b6080f2 | 9761 | { |
3dd80953 | 9762 | struct trace_event_file *file; |
121aaee7 | 9763 | int cpu; |
2b6080f2 | 9764 | |
21ccc9cd | 9765 | trace_create_file("available_tracers", TRACE_MODE_READ, d_tracer, |
607e2ea1 SRRH |
9766 | tr, &show_traces_fops); |
9767 | ||
21ccc9cd | 9768 | trace_create_file("current_tracer", TRACE_MODE_WRITE, d_tracer, |
607e2ea1 SRRH |
9769 | tr, &set_tracer_fops); |
9770 | ||
21ccc9cd | 9771 | trace_create_file("tracing_cpumask", TRACE_MODE_WRITE, d_tracer, |
ccfe9e42 AL |
9772 | tr, &tracing_cpumask_fops); |
9773 | ||
21ccc9cd | 9774 | trace_create_file("trace_options", TRACE_MODE_WRITE, d_tracer, |
2b6080f2 SR |
9775 | tr, &tracing_iter_fops); |
9776 | ||
21ccc9cd | 9777 | trace_create_file("trace", TRACE_MODE_WRITE, d_tracer, |
6484c71c | 9778 | tr, &tracing_fops); |
2b6080f2 | 9779 | |
21ccc9cd | 9780 | trace_create_file("trace_pipe", TRACE_MODE_READ, d_tracer, |
15544209 | 9781 | tr, &tracing_pipe_fops); |
2b6080f2 | 9782 | |
21ccc9cd | 9783 | trace_create_file("buffer_size_kb", TRACE_MODE_WRITE, d_tracer, |
0bc392ee | 9784 | tr, &tracing_entries_fops); |
2b6080f2 | 9785 | |
21ccc9cd | 9786 | trace_create_file("buffer_total_size_kb", TRACE_MODE_READ, d_tracer, |
2b6080f2 SR |
9787 | tr, &tracing_total_entries_fops); |
9788 | ||
238ae93d | 9789 | trace_create_file("free_buffer", 0200, d_tracer, |
2b6080f2 SR |
9790 | tr, &tracing_free_buffer_fops); |
9791 | ||
9792 | trace_create_file("trace_marker", 0220, d_tracer, | |
9793 | tr, &tracing_mark_fops); | |
9794 | ||
3dd80953 | 9795 | file = __find_event_file(tr, "ftrace", "print"); |
1ef26d8b SRG |
9796 | if (file && file->ef) |
9797 | eventfs_add_file("trigger", TRACE_MODE_WRITE, file->ef, | |
21ccc9cd | 9798 | file, &event_trigger_fops); |
3dd80953 SRV |
9799 | tr->trace_marker_file = file; |
9800 | ||
fa32e855 SR |
9801 | trace_create_file("trace_marker_raw", 0220, d_tracer, |
9802 | tr, &tracing_mark_raw_fops); | |
9803 | ||
21ccc9cd | 9804 | trace_create_file("trace_clock", TRACE_MODE_WRITE, d_tracer, tr, |
2b6080f2 SR |
9805 | &trace_clock_fops); |
9806 | ||
21ccc9cd | 9807 | trace_create_file("tracing_on", TRACE_MODE_WRITE, d_tracer, |
6484c71c | 9808 | tr, &rb_simple_fops); |
ce9bae55 | 9809 | |
21ccc9cd | 9810 | trace_create_file("timestamp_mode", TRACE_MODE_READ, d_tracer, tr, |
2c1ea60b TZ |
9811 | &trace_time_stamp_mode_fops); |
9812 | ||
a7b1d74e | 9813 | tr->buffer_percent = 50; |
03329f99 | 9814 | |
4f94559f | 9815 | trace_create_file("buffer_percent", TRACE_MODE_WRITE, d_tracer, |
03329f99 SRV |
9816 | tr, &buffer_percent_fops); |
9817 | ||
16270145 SRRH |
9818 | create_trace_options_dir(tr); |
9819 | ||
e25e43a4 | 9820 | #ifdef CONFIG_TRACER_MAX_TRACE |
91edde2e | 9821 | trace_create_maxlat_file(tr, d_tracer); |
e25e43a4 | 9822 | #endif |
6d9b3fa5 | 9823 | |
591dffda | 9824 | if (ftrace_create_function_files(tr, d_tracer)) |
24589e3a | 9825 | MEM_FAIL(1, "Could not allocate function filter files"); |
591dffda | 9826 | |
ce9bae55 | 9827 | #ifdef CONFIG_TRACER_SNAPSHOT |
21ccc9cd | 9828 | trace_create_file("snapshot", TRACE_MODE_WRITE, d_tracer, |
6484c71c | 9829 | tr, &snapshot_fops); |
ce9bae55 | 9830 | #endif |
121aaee7 | 9831 | |
21ccc9cd | 9832 | trace_create_file("error_log", TRACE_MODE_WRITE, d_tracer, |
8a062902 TZ |
9833 | tr, &tracing_err_log_fops); |
9834 | ||
121aaee7 | 9835 | for_each_tracing_cpu(cpu) |
8434dc93 | 9836 | tracing_init_tracefs_percpu(tr, cpu); |
121aaee7 | 9837 | |
345ddcc8 | 9838 | ftrace_init_tracefs(tr, d_tracer); |
2b6080f2 SR |
9839 | } |
9840 | ||
93faccbb | 9841 | static struct vfsmount *trace_automount(struct dentry *mntpt, void *ingore) |
f76180bc SRRH |
9842 | { |
9843 | struct vfsmount *mnt; | |
9844 | struct file_system_type *type; | |
9845 | ||
9846 | /* | |
9847 | * To maintain backward compatibility for tools that mount | |
9848 | * debugfs to get to the tracing facility, tracefs is automatically | |
9849 | * mounted to the debugfs/tracing directory. | |
9850 | */ | |
9851 | type = get_fs_type("tracefs"); | |
9852 | if (!type) | |
9853 | return NULL; | |
93faccbb | 9854 | mnt = vfs_submount(mntpt, type, "tracefs", NULL); |
f76180bc SRRH |
9855 | put_filesystem(type); |
9856 | if (IS_ERR(mnt)) | |
9857 | return NULL; | |
9858 | mntget(mnt); | |
9859 | ||
9860 | return mnt; | |
9861 | } | |
9862 | ||
7eeafbca SRRH |
9863 | /** |
9864 | * tracing_init_dentry - initialize top level trace array | |
9865 | * | |
9866 | * This is called when creating files or directories in the tracing | |
9867 | * directory. It is called via fs_initcall() by any of the boot up code | |
9868 | * and expects to return the dentry of the top level tracing directory. | |
9869 | */ | |
22c36b18 | 9870 | int tracing_init_dentry(void) |
7eeafbca SRRH |
9871 | { |
9872 | struct trace_array *tr = &global_trace; | |
9873 | ||
a356646a | 9874 | if (security_locked_down(LOCKDOWN_TRACEFS)) { |
ee195452 | 9875 | pr_warn("Tracing disabled due to lockdown\n"); |
22c36b18 | 9876 | return -EPERM; |
a356646a SRV |
9877 | } |
9878 | ||
f76180bc | 9879 | /* The top level trace array uses NULL as parent */ |
7eeafbca | 9880 | if (tr->dir) |
22c36b18 | 9881 | return 0; |
7eeafbca | 9882 | |
072e133d | 9883 | if (WARN_ON(!tracefs_initialized())) |
22c36b18 | 9884 | return -ENODEV; |
7eeafbca | 9885 | |
f76180bc SRRH |
9886 | /* |
9887 | * As there may still be users that expect the tracing | |
9888 | * files to exist in debugfs/tracing, we must automount | |
9889 | * the tracefs file system there, so older tools still | |
f2cc020d | 9890 | * work with the newer kernel. |
f76180bc SRRH |
9891 | */ |
9892 | tr->dir = debugfs_create_automount("tracing", NULL, | |
9893 | trace_automount, NULL); | |
7eeafbca | 9894 | |
22c36b18 | 9895 | return 0; |
7eeafbca SRRH |
9896 | } |
9897 | ||
00f4b652 JL |
9898 | extern struct trace_eval_map *__start_ftrace_eval_maps[]; |
9899 | extern struct trace_eval_map *__stop_ftrace_eval_maps[]; | |
0c564a53 | 9900 | |
f6a69466 SRV |
9901 | static struct workqueue_struct *eval_map_wq __initdata; |
9902 | static struct work_struct eval_map_work __initdata; | |
6621a700 | 9903 | static struct work_struct tracerfs_init_work __initdata; |
f6a69466 SRV |
9904 | |
9905 | static void __init eval_map_work_func(struct work_struct *work) | |
0c564a53 | 9906 | { |
3673b8e4 SRRH |
9907 | int len; |
9908 | ||
02fd7f68 | 9909 | len = __stop_ftrace_eval_maps - __start_ftrace_eval_maps; |
f57a4143 | 9910 | trace_insert_eval_map(NULL, __start_ftrace_eval_maps, len); |
3673b8e4 SRRH |
9911 | } |
9912 | ||
f6a69466 SRV |
9913 | static int __init trace_eval_init(void) |
9914 | { | |
9915 | INIT_WORK(&eval_map_work, eval_map_work_func); | |
9916 | ||
9917 | eval_map_wq = alloc_workqueue("eval_map_wq", WQ_UNBOUND, 0); | |
9918 | if (!eval_map_wq) { | |
9919 | pr_err("Unable to allocate eval_map_wq\n"); | |
9920 | /* Do work here */ | |
9921 | eval_map_work_func(&eval_map_work); | |
9922 | return -ENOMEM; | |
9923 | } | |
9924 | ||
9925 | queue_work(eval_map_wq, &eval_map_work); | |
9926 | return 0; | |
9927 | } | |
9928 | ||
6621a700 MPT |
9929 | subsys_initcall(trace_eval_init); |
9930 | ||
f6a69466 SRV |
9931 | static int __init trace_eval_sync(void) |
9932 | { | |
9933 | /* Make sure the eval map updates are finished */ | |
9934 | if (eval_map_wq) | |
9935 | destroy_workqueue(eval_map_wq); | |
9936 | return 0; | |
9937 | } | |
9938 | ||
9939 | late_initcall_sync(trace_eval_sync); | |
9940 | ||
9941 | ||
3673b8e4 | 9942 | #ifdef CONFIG_MODULES |
f57a4143 | 9943 | static void trace_module_add_evals(struct module *mod) |
3673b8e4 | 9944 | { |
99be647c | 9945 | if (!mod->num_trace_evals) |
3673b8e4 SRRH |
9946 | return; |
9947 | ||
9948 | /* | |
9949 | * Modules with bad taint do not have events created, do | |
9950 | * not bother with enums either. | |
9951 | */ | |
9952 | if (trace_module_has_bad_taint(mod)) | |
9953 | return; | |
9954 | ||
f57a4143 | 9955 | trace_insert_eval_map(mod, mod->trace_evals, mod->num_trace_evals); |
3673b8e4 SRRH |
9956 | } |
9957 | ||
681bec03 | 9958 | #ifdef CONFIG_TRACE_EVAL_MAP_FILE |
f57a4143 | 9959 | static void trace_module_remove_evals(struct module *mod) |
9828413d | 9960 | { |
23bf8cb8 JL |
9961 | union trace_eval_map_item *map; |
9962 | union trace_eval_map_item **last = &trace_eval_maps; | |
9828413d | 9963 | |
99be647c | 9964 | if (!mod->num_trace_evals) |
9828413d SRRH |
9965 | return; |
9966 | ||
1793ed93 | 9967 | mutex_lock(&trace_eval_mutex); |
9828413d | 9968 | |
23bf8cb8 | 9969 | map = trace_eval_maps; |
9828413d SRRH |
9970 | |
9971 | while (map) { | |
9972 | if (map->head.mod == mod) | |
9973 | break; | |
5f60b351 | 9974 | map = trace_eval_jmp_to_tail(map); |
9828413d SRRH |
9975 | last = &map->tail.next; |
9976 | map = map->tail.next; | |
9977 | } | |
9978 | if (!map) | |
9979 | goto out; | |
9980 | ||
5f60b351 | 9981 | *last = trace_eval_jmp_to_tail(map)->tail.next; |
9828413d SRRH |
9982 | kfree(map); |
9983 | out: | |
1793ed93 | 9984 | mutex_unlock(&trace_eval_mutex); |
9828413d SRRH |
9985 | } |
9986 | #else | |
f57a4143 | 9987 | static inline void trace_module_remove_evals(struct module *mod) { } |
681bec03 | 9988 | #endif /* CONFIG_TRACE_EVAL_MAP_FILE */ |
9828413d | 9989 | |
3673b8e4 SRRH |
9990 | static int trace_module_notify(struct notifier_block *self, |
9991 | unsigned long val, void *data) | |
9992 | { | |
9993 | struct module *mod = data; | |
9994 | ||
9995 | switch (val) { | |
9996 | case MODULE_STATE_COMING: | |
f57a4143 | 9997 | trace_module_add_evals(mod); |
3673b8e4 | 9998 | break; |
9828413d | 9999 | case MODULE_STATE_GOING: |
f57a4143 | 10000 | trace_module_remove_evals(mod); |
9828413d | 10001 | break; |
3673b8e4 SRRH |
10002 | } |
10003 | ||
0340a6b7 | 10004 | return NOTIFY_OK; |
0c564a53 SRRH |
10005 | } |
10006 | ||
3673b8e4 SRRH |
10007 | static struct notifier_block trace_module_nb = { |
10008 | .notifier_call = trace_module_notify, | |
10009 | .priority = 0, | |
10010 | }; | |
9828413d | 10011 | #endif /* CONFIG_MODULES */ |
3673b8e4 | 10012 | |
6621a700 | 10013 | static __init void tracer_init_tracefs_work_func(struct work_struct *work) |
bc0c38d1 | 10014 | { |
bc0c38d1 | 10015 | |
58b92547 SRV |
10016 | event_trace_init(); |
10017 | ||
22c36b18 WY |
10018 | init_tracer_tracefs(&global_trace, NULL); |
10019 | ftrace_init_tracefs_toplevel(&global_trace, NULL); | |
bc0c38d1 | 10020 | |
21ccc9cd | 10021 | trace_create_file("tracing_thresh", TRACE_MODE_WRITE, NULL, |
6508fa76 | 10022 | &global_trace, &tracing_thresh_fops); |
a8259075 | 10023 | |
21ccc9cd | 10024 | trace_create_file("README", TRACE_MODE_READ, NULL, |
5452af66 FW |
10025 | NULL, &tracing_readme_fops); |
10026 | ||
21ccc9cd | 10027 | trace_create_file("saved_cmdlines", TRACE_MODE_READ, NULL, |
69abe6a5 | 10028 | NULL, &tracing_saved_cmdlines_fops); |
5bf9a1ee | 10029 | |
21ccc9cd | 10030 | trace_create_file("saved_cmdlines_size", TRACE_MODE_WRITE, NULL, |
939c7a4f YY |
10031 | NULL, &tracing_saved_cmdlines_size_fops); |
10032 | ||
21ccc9cd | 10033 | trace_create_file("saved_tgids", TRACE_MODE_READ, NULL, |
99c621d7 MS |
10034 | NULL, &tracing_saved_tgids_fops); |
10035 | ||
22c36b18 | 10036 | trace_create_eval_file(NULL); |
9828413d | 10037 | |
3673b8e4 SRRH |
10038 | #ifdef CONFIG_MODULES |
10039 | register_module_notifier(&trace_module_nb); | |
10040 | #endif | |
10041 | ||
bc0c38d1 | 10042 | #ifdef CONFIG_DYNAMIC_FTRACE |
21ccc9cd | 10043 | trace_create_file("dyn_ftrace_total_info", TRACE_MODE_READ, NULL, |
da537f0a | 10044 | NULL, &tracing_dyn_info_fops); |
bc0c38d1 | 10045 | #endif |
b04cc6b1 | 10046 | |
22c36b18 | 10047 | create_trace_instances(NULL); |
5452af66 | 10048 | |
37aea98b | 10049 | update_tracer_options(&global_trace); |
6621a700 MPT |
10050 | } |
10051 | ||
10052 | static __init int tracer_init_tracefs(void) | |
10053 | { | |
10054 | int ret; | |
10055 | ||
10056 | trace_access_lock_init(); | |
10057 | ||
10058 | ret = tracing_init_dentry(); | |
10059 | if (ret) | |
10060 | return 0; | |
10061 | ||
10062 | if (eval_map_wq) { | |
10063 | INIT_WORK(&tracerfs_init_work, tracer_init_tracefs_work_func); | |
10064 | queue_work(eval_map_wq, &tracerfs_init_work); | |
10065 | } else { | |
10066 | tracer_init_tracefs_work_func(NULL); | |
10067 | } | |
09d23a1d | 10068 | |
102227b9 DBO |
10069 | rv_init_interface(); |
10070 | ||
b5ad384e | 10071 | return 0; |
bc0c38d1 SR |
10072 | } |
10073 | ||
f3860136 SRV |
10074 | fs_initcall(tracer_init_tracefs); |
10075 | ||
ea47666c GP |
10076 | static int trace_die_panic_handler(struct notifier_block *self, |
10077 | unsigned long ev, void *unused); | |
3f5a54e3 SR |
10078 | |
10079 | static struct notifier_block trace_panic_notifier = { | |
ea47666c GP |
10080 | .notifier_call = trace_die_panic_handler, |
10081 | .priority = INT_MAX - 1, | |
3f5a54e3 SR |
10082 | }; |
10083 | ||
3f5a54e3 | 10084 | static struct notifier_block trace_die_notifier = { |
ea47666c GP |
10085 | .notifier_call = trace_die_panic_handler, |
10086 | .priority = INT_MAX - 1, | |
3f5a54e3 SR |
10087 | }; |
10088 | ||
ea47666c GP |
10089 | /* |
10090 | * The idea is to execute the following die/panic callback early, in order | |
10091 | * to avoid showing irrelevant information in the trace (like other panic | |
10092 | * notifier functions); we are the 2nd to run, after hung_task/rcu_stall | |
10093 | * warnings get disabled (to prevent potential log flooding). | |
10094 | */ | |
10095 | static int trace_die_panic_handler(struct notifier_block *self, | |
10096 | unsigned long ev, void *unused) | |
10097 | { | |
10098 | if (!ftrace_dump_on_oops) | |
10099 | return NOTIFY_DONE; | |
10100 | ||
10101 | /* The die notifier requires DIE_OOPS to trigger */ | |
10102 | if (self == &trace_die_notifier && ev != DIE_OOPS) | |
10103 | return NOTIFY_DONE; | |
10104 | ||
10105 | ftrace_dump(ftrace_dump_on_oops); | |
10106 | ||
10107 | return NOTIFY_DONE; | |
10108 | } | |
10109 | ||
3f5a54e3 SR |
10110 | /* |
10111 | * printk is set to max of 1024, we really don't need it that big. | |
10112 | * Nothing should be printing 1000 characters anyway. | |
10113 | */ | |
10114 | #define TRACE_MAX_PRINT 1000 | |
10115 | ||
10116 | /* | |
10117 | * Define here KERN_TRACE so that we have one place to modify | |
10118 | * it if we decide to change what log level the ftrace dump | |
10119 | * should be at. | |
10120 | */ | |
428aee14 | 10121 | #define KERN_TRACE KERN_EMERG |
3f5a54e3 | 10122 | |
955b61e5 | 10123 | void |
3f5a54e3 SR |
10124 | trace_printk_seq(struct trace_seq *s) |
10125 | { | |
10126 | /* Probably should print a warning here. */ | |
3a161d99 SRRH |
10127 | if (s->seq.len >= TRACE_MAX_PRINT) |
10128 | s->seq.len = TRACE_MAX_PRINT; | |
3f5a54e3 | 10129 | |
820b75f6 SRRH |
10130 | /* |
10131 | * More paranoid code. Although the buffer size is set to | |
10132 | * PAGE_SIZE, and TRACE_MAX_PRINT is 1000, this is just | |
10133 | * an extra layer of protection. | |
10134 | */ | |
10135 | if (WARN_ON_ONCE(s->seq.len >= s->seq.size)) | |
10136 | s->seq.len = s->seq.size - 1; | |
3f5a54e3 SR |
10137 | |
10138 | /* should be zero ended, but we are paranoid. */ | |
3a161d99 | 10139 | s->buffer[s->seq.len] = 0; |
3f5a54e3 SR |
10140 | |
10141 | printk(KERN_TRACE "%s", s->buffer); | |
10142 | ||
f9520750 | 10143 | trace_seq_init(s); |
3f5a54e3 SR |
10144 | } |
10145 | ||
955b61e5 JW |
10146 | void trace_init_global_iter(struct trace_iterator *iter) |
10147 | { | |
10148 | iter->tr = &global_trace; | |
2b6080f2 | 10149 | iter->trace = iter->tr->current_trace; |
ae3b5093 | 10150 | iter->cpu_file = RING_BUFFER_ALL_CPUS; |
1c5eb448 | 10151 | iter->array_buffer = &global_trace.array_buffer; |
b2f974d6 CS |
10152 | |
10153 | if (iter->trace && iter->trace->open) | |
10154 | iter->trace->open(iter); | |
10155 | ||
10156 | /* Annotate start of buffers if we had overruns */ | |
1c5eb448 | 10157 | if (ring_buffer_overruns(iter->array_buffer->buffer)) |
b2f974d6 CS |
10158 | iter->iter_flags |= TRACE_FILE_ANNOTATE; |
10159 | ||
10160 | /* Output in nanoseconds only if we are using a clock in nanoseconds. */ | |
10161 | if (trace_clocks[iter->tr->clock_id].in_ns) | |
10162 | iter->iter_flags |= TRACE_FILE_TIME_IN_NS; | |
495fcec8 DA |
10163 | |
10164 | /* Can not use kmalloc for iter.temp and iter.fmt */ | |
10165 | iter->temp = static_temp_buf; | |
10166 | iter->temp_size = STATIC_TEMP_BUF_SIZE; | |
10167 | iter->fmt = static_fmt_buf; | |
10168 | iter->fmt_size = STATIC_FMT_BUF_SIZE; | |
955b61e5 JW |
10169 | } |
10170 | ||
7fe70b57 | 10171 | void ftrace_dump(enum ftrace_dump_mode oops_dump_mode) |
3f5a54e3 | 10172 | { |
3f5a54e3 SR |
10173 | /* use static because iter can be a bit big for the stack */ |
10174 | static struct trace_iterator iter; | |
7fe70b57 | 10175 | static atomic_t dump_running; |
983f938a | 10176 | struct trace_array *tr = &global_trace; |
cf586b61 | 10177 | unsigned int old_userobj; |
d769041f SR |
10178 | unsigned long flags; |
10179 | int cnt = 0, cpu; | |
3f5a54e3 | 10180 | |
7fe70b57 SRRH |
10181 | /* Only allow one dump user at a time. */ |
10182 | if (atomic_inc_return(&dump_running) != 1) { | |
10183 | atomic_dec(&dump_running); | |
10184 | return; | |
10185 | } | |
3f5a54e3 | 10186 | |
7fe70b57 SRRH |
10187 | /* |
10188 | * Always turn off tracing when we dump. | |
10189 | * We don't need to show trace output of what happens | |
10190 | * between multiple crashes. | |
10191 | * | |
10192 | * If the user does a sysrq-z, then they can re-enable | |
10193 | * tracing with echo 1 > tracing_on. | |
10194 | */ | |
0ee6b6cf | 10195 | tracing_off(); |
cf586b61 | 10196 | |
7fe70b57 | 10197 | local_irq_save(flags); |
3f5a54e3 | 10198 | |
38dbe0b1 | 10199 | /* Simulate the iterator */ |
955b61e5 JW |
10200 | trace_init_global_iter(&iter); |
10201 | ||
d769041f | 10202 | for_each_tracing_cpu(cpu) { |
1c5eb448 | 10203 | atomic_inc(&per_cpu_ptr(iter.array_buffer->data, cpu)->disabled); |
d769041f SR |
10204 | } |
10205 | ||
983f938a | 10206 | old_userobj = tr->trace_flags & TRACE_ITER_SYM_USEROBJ; |
cf586b61 | 10207 | |
b54d3de9 | 10208 | /* don't look at user memory in panic mode */ |
983f938a | 10209 | tr->trace_flags &= ~TRACE_ITER_SYM_USEROBJ; |
b54d3de9 | 10210 | |
cecbca96 FW |
10211 | switch (oops_dump_mode) { |
10212 | case DUMP_ALL: | |
ae3b5093 | 10213 | iter.cpu_file = RING_BUFFER_ALL_CPUS; |
cecbca96 FW |
10214 | break; |
10215 | case DUMP_ORIG: | |
10216 | iter.cpu_file = raw_smp_processor_id(); | |
10217 | break; | |
10218 | case DUMP_NONE: | |
10219 | goto out_enable; | |
10220 | default: | |
10221 | printk(KERN_TRACE "Bad dumping mode, switching to all CPUs dump\n"); | |
ae3b5093 | 10222 | iter.cpu_file = RING_BUFFER_ALL_CPUS; |
cecbca96 FW |
10223 | } |
10224 | ||
10225 | printk(KERN_TRACE "Dumping ftrace buffer:\n"); | |
3f5a54e3 | 10226 | |
7fe70b57 SRRH |
10227 | /* Did function tracer already get disabled? */ |
10228 | if (ftrace_is_dead()) { | |
10229 | printk("# WARNING: FUNCTION TRACING IS CORRUPTED\n"); | |
10230 | printk("# MAY BE MISSING FUNCTION EVENTS\n"); | |
10231 | } | |
10232 | ||
3f5a54e3 | 10233 | /* |
5c8c206e | 10234 | * We need to stop all tracing on all CPUS to read |
3f5a54e3 SR |
10235 | * the next buffer. This is a bit expensive, but is |
10236 | * not done often. We fill all what we can read, | |
10237 | * and then release the locks again. | |
10238 | */ | |
10239 | ||
3f5a54e3 SR |
10240 | while (!trace_empty(&iter)) { |
10241 | ||
10242 | if (!cnt) | |
10243 | printk(KERN_TRACE "---------------------------------\n"); | |
10244 | ||
10245 | cnt++; | |
10246 | ||
0c97bf86 | 10247 | trace_iterator_reset(&iter); |
3f5a54e3 | 10248 | iter.iter_flags |= TRACE_FILE_LAT_FMT; |
3f5a54e3 | 10249 | |
955b61e5 | 10250 | if (trace_find_next_entry_inc(&iter) != NULL) { |
74e7ff8c LJ |
10251 | int ret; |
10252 | ||
10253 | ret = print_trace_line(&iter); | |
10254 | if (ret != TRACE_TYPE_NO_CONSUME) | |
10255 | trace_consume(&iter); | |
3f5a54e3 | 10256 | } |
b892e5c8 | 10257 | touch_nmi_watchdog(); |
3f5a54e3 SR |
10258 | |
10259 | trace_printk_seq(&iter.seq); | |
10260 | } | |
10261 | ||
10262 | if (!cnt) | |
10263 | printk(KERN_TRACE " (ftrace buffer empty)\n"); | |
10264 | else | |
10265 | printk(KERN_TRACE "---------------------------------\n"); | |
10266 | ||
cecbca96 | 10267 | out_enable: |
983f938a | 10268 | tr->trace_flags |= old_userobj; |
cf586b61 | 10269 | |
7fe70b57 | 10270 | for_each_tracing_cpu(cpu) { |
1c5eb448 | 10271 | atomic_dec(&per_cpu_ptr(iter.array_buffer->data, cpu)->disabled); |
cf586b61 | 10272 | } |
03fc7f9c | 10273 | atomic_dec(&dump_running); |
cd891ae0 | 10274 | local_irq_restore(flags); |
3f5a54e3 | 10275 | } |
a8eecf22 | 10276 | EXPORT_SYMBOL_GPL(ftrace_dump); |
cf586b61 | 10277 | |
7e465baa TZ |
10278 | #define WRITE_BUFSIZE 4096 |
10279 | ||
10280 | ssize_t trace_parse_run_command(struct file *file, const char __user *buffer, | |
10281 | size_t count, loff_t *ppos, | |
d262271d | 10282 | int (*createfn)(const char *)) |
7e465baa TZ |
10283 | { |
10284 | char *kbuf, *buf, *tmp; | |
10285 | int ret = 0; | |
10286 | size_t done = 0; | |
10287 | size_t size; | |
10288 | ||
10289 | kbuf = kmalloc(WRITE_BUFSIZE, GFP_KERNEL); | |
10290 | if (!kbuf) | |
10291 | return -ENOMEM; | |
10292 | ||
10293 | while (done < count) { | |
10294 | size = count - done; | |
10295 | ||
10296 | if (size >= WRITE_BUFSIZE) | |
10297 | size = WRITE_BUFSIZE - 1; | |
10298 | ||
10299 | if (copy_from_user(kbuf, buffer + done, size)) { | |
10300 | ret = -EFAULT; | |
10301 | goto out; | |
10302 | } | |
10303 | kbuf[size] = '\0'; | |
10304 | buf = kbuf; | |
10305 | do { | |
10306 | tmp = strchr(buf, '\n'); | |
10307 | if (tmp) { | |
10308 | *tmp = '\0'; | |
10309 | size = tmp - buf + 1; | |
10310 | } else { | |
10311 | size = strlen(buf); | |
10312 | if (done + size < count) { | |
10313 | if (buf != kbuf) | |
10314 | break; | |
10315 | /* This can accept WRITE_BUFSIZE - 2 ('\n' + '\0') */ | |
10316 | pr_warn("Line length is too long: Should be less than %d\n", | |
10317 | WRITE_BUFSIZE - 2); | |
10318 | ret = -EINVAL; | |
10319 | goto out; | |
10320 | } | |
10321 | } | |
10322 | done += size; | |
10323 | ||
10324 | /* Remove comments */ | |
10325 | tmp = strchr(buf, '#'); | |
10326 | ||
10327 | if (tmp) | |
10328 | *tmp = '\0'; | |
10329 | ||
d262271d | 10330 | ret = createfn(buf); |
7e465baa TZ |
10331 | if (ret) |
10332 | goto out; | |
10333 | buf += size; | |
10334 | ||
10335 | } while (done < count); | |
10336 | } | |
10337 | ret = done; | |
10338 | ||
10339 | out: | |
10340 | kfree(kbuf); | |
10341 | ||
10342 | return ret; | |
10343 | } | |
10344 | ||
9c1c251d SRG |
10345 | #ifdef CONFIG_TRACER_MAX_TRACE |
10346 | __init static bool tr_needs_alloc_snapshot(const char *name) | |
10347 | { | |
10348 | char *test; | |
10349 | int len = strlen(name); | |
10350 | bool ret; | |
10351 | ||
10352 | if (!boot_snapshot_index) | |
10353 | return false; | |
10354 | ||
10355 | if (strncmp(name, boot_snapshot_info, len) == 0 && | |
10356 | boot_snapshot_info[len] == '\t') | |
10357 | return true; | |
10358 | ||
10359 | test = kmalloc(strlen(name) + 3, GFP_KERNEL); | |
10360 | if (!test) | |
10361 | return false; | |
10362 | ||
10363 | sprintf(test, "\t%s\t", name); | |
10364 | ret = strstr(boot_snapshot_info, test) == NULL; | |
10365 | kfree(test); | |
10366 | return ret; | |
10367 | } | |
10368 | ||
10369 | __init static void do_allocate_snapshot(const char *name) | |
10370 | { | |
10371 | if (!tr_needs_alloc_snapshot(name)) | |
10372 | return; | |
10373 | ||
10374 | /* | |
10375 | * When allocate_snapshot is set, the next call to | |
10376 | * allocate_trace_buffers() (called by trace_array_get_by_name()) | |
10377 | * will allocate the snapshot buffer. That will alse clear | |
10378 | * this flag. | |
10379 | */ | |
10380 | allocate_snapshot = true; | |
10381 | } | |
10382 | #else | |
10383 | static inline void do_allocate_snapshot(const char *name) { } | |
10384 | #endif | |
10385 | ||
cb1f98c5 SRG |
10386 | __init static void enable_instances(void) |
10387 | { | |
10388 | struct trace_array *tr; | |
10389 | char *curr_str; | |
10390 | char *str; | |
10391 | char *tok; | |
10392 | ||
10393 | /* A tab is always appended */ | |
10394 | boot_instance_info[boot_instance_index - 1] = '\0'; | |
10395 | str = boot_instance_info; | |
10396 | ||
10397 | while ((curr_str = strsep(&str, "\t"))) { | |
10398 | ||
10399 | tok = strsep(&curr_str, ","); | |
10400 | ||
9c1c251d SRG |
10401 | if (IS_ENABLED(CONFIG_TRACER_MAX_TRACE)) |
10402 | do_allocate_snapshot(tok); | |
10403 | ||
cb1f98c5 SRG |
10404 | tr = trace_array_get_by_name(tok); |
10405 | if (!tr) { | |
10406 | pr_warn("Failed to create instance buffer %s\n", curr_str); | |
10407 | continue; | |
10408 | } | |
10409 | /* Allow user space to delete it */ | |
10410 | trace_array_put(tr); | |
c4846480 SRG |
10411 | |
10412 | while ((tok = strsep(&curr_str, ","))) { | |
10413 | early_enable_events(tr, tok, true); | |
10414 | } | |
cb1f98c5 SRG |
10415 | } |
10416 | } | |
10417 | ||
3928a8a2 | 10418 | __init static int tracer_alloc_buffers(void) |
bc0c38d1 | 10419 | { |
73c5162a | 10420 | int ring_buf_size; |
9e01c1b7 | 10421 | int ret = -ENOMEM; |
4c11d7ae | 10422 | |
a356646a SRV |
10423 | |
10424 | if (security_locked_down(LOCKDOWN_TRACEFS)) { | |
ee195452 | 10425 | pr_warn("Tracing disabled due to lockdown\n"); |
a356646a SRV |
10426 | return -EPERM; |
10427 | } | |
10428 | ||
b5e87c05 | 10429 | /* |
499f7bb0 | 10430 | * Make sure we don't accidentally add more trace options |
b5e87c05 SRRH |
10431 | * than we have bits for. |
10432 | */ | |
9a38a885 | 10433 | BUILD_BUG_ON(TRACE_ITER_LAST_BIT > TRACE_FLAGS_MAX_SIZE); |
b5e87c05 | 10434 | |
9e01c1b7 RR |
10435 | if (!alloc_cpumask_var(&tracing_buffer_mask, GFP_KERNEL)) |
10436 | goto out; | |
10437 | ||
ccfe9e42 | 10438 | if (!alloc_cpumask_var(&global_trace.tracing_cpumask, GFP_KERNEL)) |
9e01c1b7 | 10439 | goto out_free_buffer_mask; |
4c11d7ae | 10440 | |
07d777fe | 10441 | /* Only allocate trace_printk buffers if a trace_printk exists */ |
bf2cbe04 | 10442 | if (&__stop___trace_bprintk_fmt != &__start___trace_bprintk_fmt) |
81698831 | 10443 | /* Must be called before global_trace.buffer is allocated */ |
07d777fe SR |
10444 | trace_printk_init_buffers(); |
10445 | ||
73c5162a SR |
10446 | /* To save memory, keep the ring buffer size to its minimum */ |
10447 | if (ring_buffer_expanded) | |
10448 | ring_buf_size = trace_buf_size; | |
10449 | else | |
10450 | ring_buf_size = 1; | |
10451 | ||
9e01c1b7 | 10452 | cpumask_copy(tracing_buffer_mask, cpu_possible_mask); |
ccfe9e42 | 10453 | cpumask_copy(global_trace.tracing_cpumask, cpu_all_mask); |
9e01c1b7 | 10454 | |
2b6080f2 SR |
10455 | raw_spin_lock_init(&global_trace.start_lock); |
10456 | ||
b32614c0 SAS |
10457 | /* |
10458 | * The prepare callbacks allocates some memory for the ring buffer. We | |
499f7bb0 | 10459 | * don't free the buffer if the CPU goes down. If we were to free |
b32614c0 SAS |
10460 | * the buffer, then the user would lose any trace that was in the |
10461 | * buffer. The memory will be removed once the "instance" is removed. | |
10462 | */ | |
10463 | ret = cpuhp_setup_state_multi(CPUHP_TRACE_RB_PREPARE, | |
e841e8bf | 10464 | "trace/RB:prepare", trace_rb_cpu_prepare, |
b32614c0 SAS |
10465 | NULL); |
10466 | if (ret < 0) | |
10467 | goto out_free_cpumask; | |
2c4a33ab | 10468 | /* Used for event triggers */ |
147d88e0 | 10469 | ret = -ENOMEM; |
2c4a33ab SRRH |
10470 | temp_buffer = ring_buffer_alloc(PAGE_SIZE, RB_FL_OVERWRITE); |
10471 | if (!temp_buffer) | |
b32614c0 | 10472 | goto out_rm_hp_state; |
2c4a33ab | 10473 | |
939c7a4f YY |
10474 | if (trace_create_savedcmd() < 0) |
10475 | goto out_free_temp_buffer; | |
10476 | ||
3d07fa1d | 10477 | if (!zalloc_cpumask_var(&global_trace.pipe_cpumask, GFP_KERNEL)) |
c2489bb7 ZY |
10478 | goto out_free_savedcmd; |
10479 | ||
9e01c1b7 | 10480 | /* TODO: make the number of buffers hot pluggable with CPUS */ |
737223fb | 10481 | if (allocate_trace_buffers(&global_trace, ring_buf_size) < 0) { |
24589e3a | 10482 | MEM_FAIL(1, "tracer: failed to allocate ring buffer!\n"); |
c2489bb7 | 10483 | goto out_free_pipe_cpumask; |
4c11d7ae | 10484 | } |
499e5470 SR |
10485 | if (global_trace.buffer_disabled) |
10486 | tracing_off(); | |
4c11d7ae | 10487 | |
e1e232ca SR |
10488 | if (trace_boot_clock) { |
10489 | ret = tracing_set_clock(&global_trace, trace_boot_clock); | |
10490 | if (ret < 0) | |
a395d6a7 JP |
10491 | pr_warn("Trace clock %s not defined, going back to default\n", |
10492 | trace_boot_clock); | |
e1e232ca SR |
10493 | } |
10494 | ||
ca164318 SRRH |
10495 | /* |
10496 | * register_tracer() might reference current_trace, so it | |
10497 | * needs to be set before we register anything. This is | |
10498 | * just a bootstrap of current_trace anyway. | |
10499 | */ | |
2b6080f2 SR |
10500 | global_trace.current_trace = &nop_trace; |
10501 | ||
0b9b12c1 SRRH |
10502 | global_trace.max_lock = (arch_spinlock_t)__ARCH_SPIN_LOCK_UNLOCKED; |
10503 | ||
4104d326 SRRH |
10504 | ftrace_init_global_array_ops(&global_trace); |
10505 | ||
9a38a885 SRRH |
10506 | init_trace_flags_index(&global_trace); |
10507 | ||
ca164318 SRRH |
10508 | register_tracer(&nop_trace); |
10509 | ||
dbeafd0d SRV |
10510 | /* Function tracing may start here (via kernel command line) */ |
10511 | init_function_trace(); | |
10512 | ||
60a11774 SR |
10513 | /* All seems OK, enable tracing */ |
10514 | tracing_disabled = 0; | |
3928a8a2 | 10515 | |
3f5a54e3 SR |
10516 | atomic_notifier_chain_register(&panic_notifier_list, |
10517 | &trace_panic_notifier); | |
10518 | ||
10519 | register_die_notifier(&trace_die_notifier); | |
2fc1dfbe | 10520 | |
ae63b31e SR |
10521 | global_trace.flags = TRACE_ARRAY_FL_GLOBAL; |
10522 | ||
10523 | INIT_LIST_HEAD(&global_trace.systems); | |
10524 | INIT_LIST_HEAD(&global_trace.events); | |
067fe038 | 10525 | INIT_LIST_HEAD(&global_trace.hist_vars); |
2f754e77 | 10526 | INIT_LIST_HEAD(&global_trace.err_log); |
ae63b31e SR |
10527 | list_add(&global_trace.list, &ftrace_trace_arrays); |
10528 | ||
a4d1e688 | 10529 | apply_trace_boot_options(); |
7bcfaf54 | 10530 | |
77fd5c15 SRRH |
10531 | register_snapshot_cmd(); |
10532 | ||
9a6944fe SRV |
10533 | test_can_verify(); |
10534 | ||
2fc1dfbe | 10535 | return 0; |
3f5a54e3 | 10536 | |
c2489bb7 ZY |
10537 | out_free_pipe_cpumask: |
10538 | free_cpumask_var(global_trace.pipe_cpumask); | |
939c7a4f YY |
10539 | out_free_savedcmd: |
10540 | free_saved_cmdlines_buffer(savedcmd); | |
2c4a33ab SRRH |
10541 | out_free_temp_buffer: |
10542 | ring_buffer_free(temp_buffer); | |
b32614c0 SAS |
10543 | out_rm_hp_state: |
10544 | cpuhp_remove_multi_state(CPUHP_TRACE_RB_PREPARE); | |
9e01c1b7 | 10545 | out_free_cpumask: |
ccfe9e42 | 10546 | free_cpumask_var(global_trace.tracing_cpumask); |
9e01c1b7 RR |
10547 | out_free_buffer_mask: |
10548 | free_cpumask_var(tracing_buffer_mask); | |
10549 | out: | |
10550 | return ret; | |
bc0c38d1 | 10551 | } |
b2821ae6 | 10552 | |
380af29b SRG |
10553 | void __init ftrace_boot_snapshot(void) |
10554 | { | |
e9489164 | 10555 | #ifdef CONFIG_TRACER_MAX_TRACE |
9c1c251d SRG |
10556 | struct trace_array *tr; |
10557 | ||
e9489164 SRG |
10558 | if (!snapshot_at_boot) |
10559 | return; | |
9c1c251d SRG |
10560 | |
10561 | list_for_each_entry(tr, &ftrace_trace_arrays, list) { | |
e9489164 | 10562 | if (!tr->allocated_snapshot) |
9c1c251d | 10563 | continue; |
e9489164 | 10564 | |
9c1c251d | 10565 | tracing_snapshot_instance(tr); |
e9489164 | 10566 | trace_array_puts(tr, "** Boot snapshot taken **\n"); |
9c1c251d | 10567 | } |
e9489164 | 10568 | #endif |
380af29b SRG |
10569 | } |
10570 | ||
e725c731 | 10571 | void __init early_trace_init(void) |
5f893b26 | 10572 | { |
0daa2302 SRRH |
10573 | if (tracepoint_printk) { |
10574 | tracepoint_print_iter = | |
0e1e71d3 | 10575 | kzalloc(sizeof(*tracepoint_print_iter), GFP_KERNEL); |
24589e3a SRV |
10576 | if (MEM_FAIL(!tracepoint_print_iter, |
10577 | "Failed to allocate trace iterator\n")) | |
0daa2302 | 10578 | tracepoint_printk = 0; |
42391745 SRRH |
10579 | else |
10580 | static_key_enable(&tracepoint_printk_key.key); | |
0daa2302 | 10581 | } |
5f893b26 | 10582 | tracer_alloc_buffers(); |
3bb06eb6 SRG |
10583 | |
10584 | init_events(); | |
e725c731 SRV |
10585 | } |
10586 | ||
10587 | void __init trace_init(void) | |
10588 | { | |
0c564a53 | 10589 | trace_event_init(); |
cb1f98c5 SRG |
10590 | |
10591 | if (boot_instance_index) | |
10592 | enable_instances(); | |
5f893b26 SRRH |
10593 | } |
10594 | ||
f3860136 | 10595 | __init static void clear_boot_tracer(void) |
b2821ae6 SR |
10596 | { |
10597 | /* | |
10598 | * The default tracer at boot buffer is an init section. | |
10599 | * This function is called in lateinit. If we did not | |
10600 | * find the boot tracer, then clear it out, to prevent | |
10601 | * later registration from accessing the buffer that is | |
10602 | * about to be freed. | |
10603 | */ | |
10604 | if (!default_bootup_tracer) | |
f3860136 | 10605 | return; |
b2821ae6 SR |
10606 | |
10607 | printk(KERN_INFO "ftrace bootup tracer '%s' not registered.\n", | |
10608 | default_bootup_tracer); | |
10609 | default_bootup_tracer = NULL; | |
b2821ae6 SR |
10610 | } |
10611 | ||
3fd49c9e | 10612 | #ifdef CONFIG_HAVE_UNSTABLE_SCHED_CLOCK |
f3860136 | 10613 | __init static void tracing_set_default_clock(void) |
3fd49c9e CW |
10614 | { |
10615 | /* sched_clock_stable() is determined in late_initcall */ | |
5125eee4 | 10616 | if (!trace_boot_clock && !sched_clock_stable()) { |
bf24daac MI |
10617 | if (security_locked_down(LOCKDOWN_TRACEFS)) { |
10618 | pr_warn("Can not set tracing clock due to lockdown\n"); | |
f3860136 | 10619 | return; |
bf24daac MI |
10620 | } |
10621 | ||
3fd49c9e CW |
10622 | printk(KERN_WARNING |
10623 | "Unstable clock detected, switching default tracing clock to \"global\"\n" | |
10624 | "If you want to keep using the local clock, then add:\n" | |
10625 | " \"trace_clock=local\"\n" | |
10626 | "on the kernel command line\n"); | |
10627 | tracing_set_clock(&global_trace, "global"); | |
10628 | } | |
f3860136 SRV |
10629 | } |
10630 | #else | |
10631 | static inline void tracing_set_default_clock(void) { } | |
10632 | #endif | |
3fd49c9e | 10633 | |
f3860136 SRV |
10634 | __init static int late_trace_init(void) |
10635 | { | |
10636 | if (tracepoint_printk && tracepoint_printk_stop_on_boot) { | |
10637 | static_key_disable(&tracepoint_printk_key.key); | |
10638 | tracepoint_printk = 0; | |
10639 | } | |
3fd49c9e | 10640 | |
f3860136 SRV |
10641 | tracing_set_default_clock(); |
10642 | clear_boot_tracer(); | |
3fd49c9e CW |
10643 | return 0; |
10644 | } | |
f3860136 SRV |
10645 | |
10646 | late_initcall_sync(late_trace_init); |