Commit | Line | Data |
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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> |
3f5a54e3 | 22 | #include <linux/notifier.h> |
2cadf913 | 23 | #include <linux/irqflags.h> |
bc0c38d1 | 24 | #include <linux/debugfs.h> |
8434dc93 | 25 | #include <linux/tracefs.h> |
4c11d7ae | 26 | #include <linux/pagemap.h> |
bc0c38d1 SR |
27 | #include <linux/hardirq.h> |
28 | #include <linux/linkage.h> | |
29 | #include <linux/uaccess.h> | |
76c813e2 | 30 | #include <linux/vmalloc.h> |
bc0c38d1 SR |
31 | #include <linux/ftrace.h> |
32 | #include <linux/module.h> | |
33 | #include <linux/percpu.h> | |
2cadf913 | 34 | #include <linux/splice.h> |
3f5a54e3 | 35 | #include <linux/kdebug.h> |
5f0c6c03 | 36 | #include <linux/string.h> |
f76180bc | 37 | #include <linux/mount.h> |
7e53bd42 | 38 | #include <linux/rwsem.h> |
5a0e3ad6 | 39 | #include <linux/slab.h> |
bc0c38d1 SR |
40 | #include <linux/ctype.h> |
41 | #include <linux/init.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 | |
bc0c38d1 | 52 | #include "trace.h" |
f0868d1e | 53 | #include "trace_output.h" |
bc0c38d1 | 54 | |
73c5162a SR |
55 | /* |
56 | * On boot up, the ring buffer is set to the minimum size, so that | |
57 | * we do not waste memory on systems that are not using tracing. | |
58 | */ | |
55034cd6 | 59 | bool ring_buffer_expanded; |
73c5162a | 60 | |
8e1b82e0 FW |
61 | /* |
62 | * We need to change this state when a selftest is running. | |
ff32504f FW |
63 | * A selftest will lurk into the ring-buffer to count the |
64 | * entries inserted during the selftest although some concurrent | |
5e1607a0 | 65 | * insertions into the ring-buffer such as trace_printk could occurred |
ff32504f FW |
66 | * at the same time, giving false positive or negative results. |
67 | */ | |
8e1b82e0 | 68 | static bool __read_mostly tracing_selftest_running; |
ff32504f | 69 | |
b2821ae6 | 70 | /* |
60efe21e MH |
71 | * If boot-time tracing including tracers/events via kernel cmdline |
72 | * is running, we do not want to run SELFTEST. | |
b2821ae6 | 73 | */ |
020e5f85 | 74 | bool __read_mostly tracing_selftest_disabled; |
b2821ae6 | 75 | |
60efe21e MH |
76 | #ifdef CONFIG_FTRACE_STARTUP_TEST |
77 | void __init disable_tracing_selftest(const char *reason) | |
78 | { | |
79 | if (!tracing_selftest_disabled) { | |
80 | tracing_selftest_disabled = true; | |
81 | pr_info("Ftrace startup test is disabled due to %s\n", reason); | |
82 | } | |
83 | } | |
84 | #endif | |
85 | ||
0daa2302 SRRH |
86 | /* Pipe tracepoints to printk */ |
87 | struct trace_iterator *tracepoint_print_iter; | |
88 | int tracepoint_printk; | |
42391745 | 89 | static DEFINE_STATIC_KEY_FALSE(tracepoint_printk_key); |
0daa2302 | 90 | |
adf9f195 FW |
91 | /* For tracers that don't implement custom flags */ |
92 | static struct tracer_opt dummy_tracer_opt[] = { | |
93 | { } | |
94 | }; | |
95 | ||
8c1a49ae SRRH |
96 | static int |
97 | dummy_set_flag(struct trace_array *tr, u32 old_flags, u32 bit, int set) | |
adf9f195 FW |
98 | { |
99 | return 0; | |
100 | } | |
0f048701 | 101 | |
7ffbd48d SR |
102 | /* |
103 | * To prevent the comm cache from being overwritten when no | |
104 | * tracing is active, only save the comm when a trace event | |
105 | * occurred. | |
106 | */ | |
d914ba37 | 107 | static DEFINE_PER_CPU(bool, trace_taskinfo_save); |
7ffbd48d | 108 | |
0f048701 SR |
109 | /* |
110 | * Kill all tracing for good (never come back). | |
111 | * It is initialized to 1 but will turn to zero if the initialization | |
112 | * of the tracer is successful. But that is the only place that sets | |
113 | * this back to zero. | |
114 | */ | |
4fd27358 | 115 | static int tracing_disabled = 1; |
0f048701 | 116 | |
955b61e5 | 117 | cpumask_var_t __read_mostly tracing_buffer_mask; |
ab46428c | 118 | |
944ac425 SR |
119 | /* |
120 | * ftrace_dump_on_oops - variable to dump ftrace buffer on oops | |
121 | * | |
122 | * If there is an oops (or kernel panic) and the ftrace_dump_on_oops | |
123 | * is set, then ftrace_dump is called. This will output the contents | |
124 | * of the ftrace buffers to the console. This is very useful for | |
125 | * capturing traces that lead to crashes and outputing it to a | |
126 | * serial console. | |
127 | * | |
128 | * It is default off, but you can enable it with either specifying | |
129 | * "ftrace_dump_on_oops" in the kernel command line, or setting | |
cecbca96 FW |
130 | * /proc/sys/kernel/ftrace_dump_on_oops |
131 | * Set 1 if you want to dump buffers of all CPUs | |
132 | * Set 2 if you want to dump the buffer of the CPU that triggered oops | |
944ac425 | 133 | */ |
cecbca96 FW |
134 | |
135 | enum ftrace_dump_mode ftrace_dump_on_oops; | |
944ac425 | 136 | |
de7edd31 SRRH |
137 | /* When set, tracing will stop when a WARN*() is hit */ |
138 | int __disable_trace_on_warning; | |
139 | ||
681bec03 JL |
140 | #ifdef CONFIG_TRACE_EVAL_MAP_FILE |
141 | /* Map of enums to their values, for "eval_map" file */ | |
23bf8cb8 | 142 | struct trace_eval_map_head { |
9828413d SRRH |
143 | struct module *mod; |
144 | unsigned long length; | |
145 | }; | |
146 | ||
23bf8cb8 | 147 | union trace_eval_map_item; |
9828413d | 148 | |
23bf8cb8 | 149 | struct trace_eval_map_tail { |
9828413d SRRH |
150 | /* |
151 | * "end" is first and points to NULL as it must be different | |
00f4b652 | 152 | * than "mod" or "eval_string" |
9828413d | 153 | */ |
23bf8cb8 | 154 | union trace_eval_map_item *next; |
9828413d SRRH |
155 | const char *end; /* points to NULL */ |
156 | }; | |
157 | ||
1793ed93 | 158 | static DEFINE_MUTEX(trace_eval_mutex); |
9828413d SRRH |
159 | |
160 | /* | |
23bf8cb8 | 161 | * The trace_eval_maps are saved in an array with two extra elements, |
9828413d SRRH |
162 | * one at the beginning, and one at the end. The beginning item contains |
163 | * the count of the saved maps (head.length), and the module they | |
164 | * belong to if not built in (head.mod). The ending item contains a | |
681bec03 | 165 | * pointer to the next array of saved eval_map items. |
9828413d | 166 | */ |
23bf8cb8 | 167 | union trace_eval_map_item { |
00f4b652 | 168 | struct trace_eval_map map; |
23bf8cb8 JL |
169 | struct trace_eval_map_head head; |
170 | struct trace_eval_map_tail tail; | |
9828413d SRRH |
171 | }; |
172 | ||
23bf8cb8 | 173 | static union trace_eval_map_item *trace_eval_maps; |
681bec03 | 174 | #endif /* CONFIG_TRACE_EVAL_MAP_FILE */ |
9828413d | 175 | |
9c5b9d3d | 176 | int tracing_set_tracer(struct trace_array *tr, const char *buf); |
bcee5278 SRV |
177 | static void ftrace_trace_userstack(struct trace_array *tr, |
178 | struct trace_buffer *buffer, | |
36590c50 | 179 | unsigned int trace_ctx); |
b2821ae6 | 180 | |
ee6c2c1b LZ |
181 | #define MAX_TRACER_SIZE 100 |
182 | static char bootup_tracer_buf[MAX_TRACER_SIZE] __initdata; | |
b2821ae6 | 183 | static char *default_bootup_tracer; |
d9e54076 | 184 | |
55034cd6 SRRH |
185 | static bool allocate_snapshot; |
186 | ||
1beee96b | 187 | static int __init set_cmdline_ftrace(char *str) |
d9e54076 | 188 | { |
67012ab1 | 189 | strlcpy(bootup_tracer_buf, str, MAX_TRACER_SIZE); |
b2821ae6 | 190 | default_bootup_tracer = bootup_tracer_buf; |
73c5162a | 191 | /* We are using ftrace early, expand it */ |
55034cd6 | 192 | ring_buffer_expanded = true; |
d9e54076 PZ |
193 | return 1; |
194 | } | |
1beee96b | 195 | __setup("ftrace=", set_cmdline_ftrace); |
d9e54076 | 196 | |
944ac425 SR |
197 | static int __init set_ftrace_dump_on_oops(char *str) |
198 | { | |
cecbca96 FW |
199 | if (*str++ != '=' || !*str) { |
200 | ftrace_dump_on_oops = DUMP_ALL; | |
201 | return 1; | |
202 | } | |
203 | ||
204 | if (!strcmp("orig_cpu", str)) { | |
205 | ftrace_dump_on_oops = DUMP_ORIG; | |
206 | return 1; | |
207 | } | |
208 | ||
209 | return 0; | |
944ac425 SR |
210 | } |
211 | __setup("ftrace_dump_on_oops", set_ftrace_dump_on_oops); | |
60a11774 | 212 | |
de7edd31 SRRH |
213 | static int __init stop_trace_on_warning(char *str) |
214 | { | |
933ff9f2 LCG |
215 | if ((strcmp(str, "=0") != 0 && strcmp(str, "=off") != 0)) |
216 | __disable_trace_on_warning = 1; | |
de7edd31 SRRH |
217 | return 1; |
218 | } | |
933ff9f2 | 219 | __setup("traceoff_on_warning", stop_trace_on_warning); |
de7edd31 | 220 | |
3209cff4 | 221 | static int __init boot_alloc_snapshot(char *str) |
55034cd6 SRRH |
222 | { |
223 | allocate_snapshot = true; | |
224 | /* We also need the main ring buffer expanded */ | |
225 | ring_buffer_expanded = true; | |
226 | return 1; | |
227 | } | |
3209cff4 | 228 | __setup("alloc_snapshot", boot_alloc_snapshot); |
55034cd6 | 229 | |
7bcfaf54 SR |
230 | |
231 | static char trace_boot_options_buf[MAX_TRACER_SIZE] __initdata; | |
7bcfaf54 SR |
232 | |
233 | static int __init set_trace_boot_options(char *str) | |
234 | { | |
67012ab1 | 235 | strlcpy(trace_boot_options_buf, str, MAX_TRACER_SIZE); |
7bcfaf54 SR |
236 | return 0; |
237 | } | |
238 | __setup("trace_options=", set_trace_boot_options); | |
239 | ||
e1e232ca SR |
240 | static char trace_boot_clock_buf[MAX_TRACER_SIZE] __initdata; |
241 | static char *trace_boot_clock __initdata; | |
242 | ||
243 | static int __init set_trace_boot_clock(char *str) | |
244 | { | |
245 | strlcpy(trace_boot_clock_buf, str, MAX_TRACER_SIZE); | |
246 | trace_boot_clock = trace_boot_clock_buf; | |
247 | return 0; | |
248 | } | |
249 | __setup("trace_clock=", set_trace_boot_clock); | |
250 | ||
0daa2302 SRRH |
251 | static int __init set_tracepoint_printk(char *str) |
252 | { | |
253 | if ((strcmp(str, "=0") != 0 && strcmp(str, "=off") != 0)) | |
254 | tracepoint_printk = 1; | |
255 | return 1; | |
256 | } | |
257 | __setup("tp_printk", set_tracepoint_printk); | |
de7edd31 | 258 | |
a5a1d1c2 | 259 | unsigned long long ns2usecs(u64 nsec) |
bc0c38d1 SR |
260 | { |
261 | nsec += 500; | |
262 | do_div(nsec, 1000); | |
263 | return nsec; | |
264 | } | |
265 | ||
8ab7a2b7 TZ |
266 | static void |
267 | trace_process_export(struct trace_export *export, | |
268 | struct ring_buffer_event *event, int flag) | |
269 | { | |
270 | struct trace_entry *entry; | |
271 | unsigned int size = 0; | |
272 | ||
273 | if (export->flags & flag) { | |
274 | entry = ring_buffer_event_data(event); | |
275 | size = ring_buffer_event_length(event); | |
276 | export->write(export, entry, size); | |
277 | } | |
278 | } | |
279 | ||
280 | static DEFINE_MUTEX(ftrace_export_lock); | |
281 | ||
282 | static struct trace_export __rcu *ftrace_exports_list __read_mostly; | |
283 | ||
284 | static DEFINE_STATIC_KEY_FALSE(trace_function_exports_enabled); | |
285 | static DEFINE_STATIC_KEY_FALSE(trace_event_exports_enabled); | |
458999c6 | 286 | static DEFINE_STATIC_KEY_FALSE(trace_marker_exports_enabled); |
8ab7a2b7 TZ |
287 | |
288 | static inline void ftrace_exports_enable(struct trace_export *export) | |
289 | { | |
290 | if (export->flags & TRACE_EXPORT_FUNCTION) | |
291 | static_branch_inc(&trace_function_exports_enabled); | |
292 | ||
293 | if (export->flags & TRACE_EXPORT_EVENT) | |
294 | static_branch_inc(&trace_event_exports_enabled); | |
458999c6 TZ |
295 | |
296 | if (export->flags & TRACE_EXPORT_MARKER) | |
297 | static_branch_inc(&trace_marker_exports_enabled); | |
8ab7a2b7 TZ |
298 | } |
299 | ||
300 | static inline void ftrace_exports_disable(struct trace_export *export) | |
301 | { | |
302 | if (export->flags & TRACE_EXPORT_FUNCTION) | |
303 | static_branch_dec(&trace_function_exports_enabled); | |
304 | ||
305 | if (export->flags & TRACE_EXPORT_EVENT) | |
306 | static_branch_dec(&trace_event_exports_enabled); | |
458999c6 TZ |
307 | |
308 | if (export->flags & TRACE_EXPORT_MARKER) | |
309 | static_branch_dec(&trace_marker_exports_enabled); | |
8ab7a2b7 TZ |
310 | } |
311 | ||
312 | static void ftrace_exports(struct ring_buffer_event *event, int flag) | |
313 | { | |
314 | struct trace_export *export; | |
315 | ||
316 | preempt_disable_notrace(); | |
317 | ||
318 | export = rcu_dereference_raw_check(ftrace_exports_list); | |
319 | while (export) { | |
320 | trace_process_export(export, event, flag); | |
321 | export = rcu_dereference_raw_check(export->next); | |
322 | } | |
323 | ||
324 | preempt_enable_notrace(); | |
325 | } | |
326 | ||
327 | static inline void | |
328 | add_trace_export(struct trace_export **list, struct trace_export *export) | |
329 | { | |
330 | rcu_assign_pointer(export->next, *list); | |
331 | /* | |
332 | * We are entering export into the list but another | |
333 | * CPU might be walking that list. We need to make sure | |
334 | * the export->next pointer is valid before another CPU sees | |
335 | * the export pointer included into the list. | |
336 | */ | |
337 | rcu_assign_pointer(*list, export); | |
338 | } | |
339 | ||
340 | static inline int | |
341 | rm_trace_export(struct trace_export **list, struct trace_export *export) | |
342 | { | |
343 | struct trace_export **p; | |
344 | ||
345 | for (p = list; *p != NULL; p = &(*p)->next) | |
346 | if (*p == export) | |
347 | break; | |
348 | ||
349 | if (*p != export) | |
350 | return -1; | |
351 | ||
352 | rcu_assign_pointer(*p, (*p)->next); | |
353 | ||
354 | return 0; | |
355 | } | |
356 | ||
357 | static inline void | |
358 | add_ftrace_export(struct trace_export **list, struct trace_export *export) | |
359 | { | |
360 | ftrace_exports_enable(export); | |
361 | ||
362 | add_trace_export(list, export); | |
363 | } | |
364 | ||
365 | static inline int | |
366 | rm_ftrace_export(struct trace_export **list, struct trace_export *export) | |
367 | { | |
368 | int ret; | |
369 | ||
370 | ret = rm_trace_export(list, export); | |
371 | ftrace_exports_disable(export); | |
372 | ||
373 | return ret; | |
374 | } | |
375 | ||
376 | int register_ftrace_export(struct trace_export *export) | |
377 | { | |
378 | if (WARN_ON_ONCE(!export->write)) | |
379 | return -1; | |
380 | ||
381 | mutex_lock(&ftrace_export_lock); | |
382 | ||
383 | add_ftrace_export(&ftrace_exports_list, export); | |
384 | ||
385 | mutex_unlock(&ftrace_export_lock); | |
386 | ||
387 | return 0; | |
388 | } | |
389 | EXPORT_SYMBOL_GPL(register_ftrace_export); | |
390 | ||
391 | int unregister_ftrace_export(struct trace_export *export) | |
392 | { | |
393 | int ret; | |
394 | ||
395 | mutex_lock(&ftrace_export_lock); | |
396 | ||
397 | ret = rm_ftrace_export(&ftrace_exports_list, export); | |
398 | ||
399 | mutex_unlock(&ftrace_export_lock); | |
400 | ||
401 | return ret; | |
402 | } | |
403 | EXPORT_SYMBOL_GPL(unregister_ftrace_export); | |
404 | ||
983f938a SRRH |
405 | /* trace_flags holds trace_options default values */ |
406 | #define TRACE_DEFAULT_FLAGS \ | |
407 | (FUNCTION_DEFAULT_FLAGS | \ | |
408 | TRACE_ITER_PRINT_PARENT | TRACE_ITER_PRINTK | \ | |
409 | TRACE_ITER_ANNOTATE | TRACE_ITER_CONTEXT_INFO | \ | |
410 | TRACE_ITER_RECORD_CMD | TRACE_ITER_OVERWRITE | \ | |
99e22ce7 SRV |
411 | TRACE_ITER_IRQ_INFO | TRACE_ITER_MARKERS | \ |
412 | TRACE_ITER_HASH_PTR) | |
983f938a | 413 | |
16270145 SRRH |
414 | /* trace_options that are only supported by global_trace */ |
415 | #define TOP_LEVEL_TRACE_FLAGS (TRACE_ITER_PRINTK | \ | |
416 | TRACE_ITER_PRINTK_MSGONLY | TRACE_ITER_RECORD_CMD) | |
417 | ||
20550622 SRRH |
418 | /* trace_flags that are default zero for instances */ |
419 | #define ZEROED_TRACE_FLAGS \ | |
1e10486f | 420 | (TRACE_ITER_EVENT_FORK | TRACE_ITER_FUNC_FORK) |
16270145 | 421 | |
4fcdae83 | 422 | /* |
67d04bb2 JF |
423 | * The global_trace is the descriptor that holds the top-level tracing |
424 | * buffers for the live tracing. | |
4fcdae83 | 425 | */ |
983f938a SRRH |
426 | static struct trace_array global_trace = { |
427 | .trace_flags = TRACE_DEFAULT_FLAGS, | |
428 | }; | |
bc0c38d1 | 429 | |
ae63b31e | 430 | LIST_HEAD(ftrace_trace_arrays); |
bc0c38d1 | 431 | |
ff451961 SRRH |
432 | int trace_array_get(struct trace_array *this_tr) |
433 | { | |
434 | struct trace_array *tr; | |
435 | int ret = -ENODEV; | |
436 | ||
437 | mutex_lock(&trace_types_lock); | |
438 | list_for_each_entry(tr, &ftrace_trace_arrays, list) { | |
439 | if (tr == this_tr) { | |
440 | tr->ref++; | |
441 | ret = 0; | |
442 | break; | |
443 | } | |
444 | } | |
445 | mutex_unlock(&trace_types_lock); | |
446 | ||
447 | return ret; | |
448 | } | |
449 | ||
450 | static void __trace_array_put(struct trace_array *this_tr) | |
451 | { | |
452 | WARN_ON(!this_tr->ref); | |
453 | this_tr->ref--; | |
454 | } | |
455 | ||
28879787 DI |
456 | /** |
457 | * trace_array_put - Decrement the reference counter for this trace array. | |
557d50e7 | 458 | * @this_tr : pointer to the trace array |
28879787 DI |
459 | * |
460 | * NOTE: Use this when we no longer need the trace array returned by | |
461 | * trace_array_get_by_name(). This ensures the trace array can be later | |
462 | * destroyed. | |
463 | * | |
464 | */ | |
ff451961 SRRH |
465 | void trace_array_put(struct trace_array *this_tr) |
466 | { | |
28879787 DI |
467 | if (!this_tr) |
468 | return; | |
469 | ||
ff451961 SRRH |
470 | mutex_lock(&trace_types_lock); |
471 | __trace_array_put(this_tr); | |
472 | mutex_unlock(&trace_types_lock); | |
473 | } | |
28879787 | 474 | EXPORT_SYMBOL_GPL(trace_array_put); |
ff451961 | 475 | |
8530dec6 SRV |
476 | int tracing_check_open_get_tr(struct trace_array *tr) |
477 | { | |
17911ff3 SRV |
478 | int ret; |
479 | ||
480 | ret = security_locked_down(LOCKDOWN_TRACEFS); | |
481 | if (ret) | |
482 | return ret; | |
483 | ||
8530dec6 SRV |
484 | if (tracing_disabled) |
485 | return -ENODEV; | |
486 | ||
487 | if (tr && trace_array_get(tr) < 0) | |
488 | return -ENODEV; | |
489 | ||
490 | return 0; | |
491 | } | |
492 | ||
2425bcb9 | 493 | int call_filter_check_discard(struct trace_event_call *call, void *rec, |
13292494 | 494 | struct trace_buffer *buffer, |
f306cc82 TZ |
495 | struct ring_buffer_event *event) |
496 | { | |
497 | if (unlikely(call->flags & TRACE_EVENT_FL_FILTERED) && | |
498 | !filter_match_preds(call->filter, rec)) { | |
0fc1b09f | 499 | __trace_event_discard_commit(buffer, event); |
f306cc82 TZ |
500 | return 1; |
501 | } | |
502 | ||
503 | return 0; | |
eb02ce01 TZ |
504 | } |
505 | ||
76c813e2 SRRH |
506 | void trace_free_pid_list(struct trace_pid_list *pid_list) |
507 | { | |
508 | vfree(pid_list->pids); | |
509 | kfree(pid_list); | |
510 | } | |
511 | ||
d8275c45 SR |
512 | /** |
513 | * trace_find_filtered_pid - check if a pid exists in a filtered_pid list | |
514 | * @filtered_pids: The list of pids to check | |
515 | * @search_pid: The PID to find in @filtered_pids | |
516 | * | |
f2cc020d | 517 | * Returns true if @search_pid is found in @filtered_pids, and false otherwise. |
d8275c45 SR |
518 | */ |
519 | bool | |
520 | trace_find_filtered_pid(struct trace_pid_list *filtered_pids, pid_t search_pid) | |
521 | { | |
522 | /* | |
523 | * If pid_max changed after filtered_pids was created, we | |
524 | * by default ignore all pids greater than the previous pid_max. | |
525 | */ | |
526 | if (search_pid >= filtered_pids->pid_max) | |
527 | return false; | |
528 | ||
529 | return test_bit(search_pid, filtered_pids->pids); | |
530 | } | |
531 | ||
532 | /** | |
533 | * trace_ignore_this_task - should a task be ignored for tracing | |
534 | * @filtered_pids: The list of pids to check | |
b3ca59f6 | 535 | * @filtered_no_pids: The list of pids not to be traced |
d8275c45 SR |
536 | * @task: The task that should be ignored if not filtered |
537 | * | |
538 | * Checks if @task should be traced or not from @filtered_pids. | |
539 | * Returns true if @task should *NOT* be traced. | |
540 | * Returns false if @task should be traced. | |
541 | */ | |
542 | bool | |
b3b1e6ed SRV |
543 | trace_ignore_this_task(struct trace_pid_list *filtered_pids, |
544 | struct trace_pid_list *filtered_no_pids, | |
545 | struct task_struct *task) | |
d8275c45 SR |
546 | { |
547 | /* | |
f2cc020d | 548 | * If filtered_no_pids is not empty, and the task's pid is listed |
b3b1e6ed SRV |
549 | * in filtered_no_pids, then return true. |
550 | * Otherwise, if filtered_pids is empty, that means we can | |
551 | * trace all tasks. If it has content, then only trace pids | |
552 | * within filtered_pids. | |
d8275c45 | 553 | */ |
d8275c45 | 554 | |
b3b1e6ed SRV |
555 | return (filtered_pids && |
556 | !trace_find_filtered_pid(filtered_pids, task->pid)) || | |
557 | (filtered_no_pids && | |
558 | trace_find_filtered_pid(filtered_no_pids, task->pid)); | |
d8275c45 SR |
559 | } |
560 | ||
561 | /** | |
f08367b3 | 562 | * trace_filter_add_remove_task - Add or remove a task from a pid_list |
d8275c45 SR |
563 | * @pid_list: The list to modify |
564 | * @self: The current task for fork or NULL for exit | |
565 | * @task: The task to add or remove | |
566 | * | |
567 | * If adding a task, if @self is defined, the task is only added if @self | |
568 | * is also included in @pid_list. This happens on fork and tasks should | |
569 | * only be added when the parent is listed. If @self is NULL, then the | |
570 | * @task pid will be removed from the list, which would happen on exit | |
571 | * of a task. | |
572 | */ | |
573 | void trace_filter_add_remove_task(struct trace_pid_list *pid_list, | |
574 | struct task_struct *self, | |
575 | struct task_struct *task) | |
576 | { | |
577 | if (!pid_list) | |
578 | return; | |
579 | ||
580 | /* For forks, we only add if the forking task is listed */ | |
581 | if (self) { | |
582 | if (!trace_find_filtered_pid(pid_list, self->pid)) | |
583 | return; | |
584 | } | |
585 | ||
586 | /* Sorry, but we don't support pid_max changing after setting */ | |
587 | if (task->pid >= pid_list->pid_max) | |
588 | return; | |
589 | ||
590 | /* "self" is set for forks, and NULL for exits */ | |
591 | if (self) | |
592 | set_bit(task->pid, pid_list->pids); | |
593 | else | |
594 | clear_bit(task->pid, pid_list->pids); | |
595 | } | |
596 | ||
5cc8976b SRRH |
597 | /** |
598 | * trace_pid_next - Used for seq_file to get to the next pid of a pid_list | |
599 | * @pid_list: The pid list to show | |
600 | * @v: The last pid that was shown (+1 the actual pid to let zero be displayed) | |
601 | * @pos: The position of the file | |
602 | * | |
603 | * This is used by the seq_file "next" operation to iterate the pids | |
604 | * listed in a trace_pid_list structure. | |
605 | * | |
606 | * Returns the pid+1 as we want to display pid of zero, but NULL would | |
607 | * stop the iteration. | |
608 | */ | |
609 | void *trace_pid_next(struct trace_pid_list *pid_list, void *v, loff_t *pos) | |
610 | { | |
611 | unsigned long pid = (unsigned long)v; | |
612 | ||
613 | (*pos)++; | |
614 | ||
f2cc020d | 615 | /* pid already is +1 of the actual previous bit */ |
5cc8976b SRRH |
616 | pid = find_next_bit(pid_list->pids, pid_list->pid_max, pid); |
617 | ||
618 | /* Return pid + 1 to allow zero to be represented */ | |
619 | if (pid < pid_list->pid_max) | |
620 | return (void *)(pid + 1); | |
621 | ||
622 | return NULL; | |
623 | } | |
624 | ||
625 | /** | |
626 | * trace_pid_start - Used for seq_file to start reading pid lists | |
627 | * @pid_list: The pid list to show | |
628 | * @pos: The position of the file | |
629 | * | |
630 | * This is used by seq_file "start" operation to start the iteration | |
631 | * of listing pids. | |
632 | * | |
633 | * Returns the pid+1 as we want to display pid of zero, but NULL would | |
634 | * stop the iteration. | |
635 | */ | |
636 | void *trace_pid_start(struct trace_pid_list *pid_list, loff_t *pos) | |
637 | { | |
638 | unsigned long pid; | |
639 | loff_t l = 0; | |
640 | ||
641 | pid = find_first_bit(pid_list->pids, pid_list->pid_max); | |
642 | if (pid >= pid_list->pid_max) | |
643 | return NULL; | |
644 | ||
645 | /* Return pid + 1 so that zero can be the exit value */ | |
646 | for (pid++; pid && l < *pos; | |
647 | pid = (unsigned long)trace_pid_next(pid_list, (void *)pid, &l)) | |
648 | ; | |
649 | return (void *)pid; | |
650 | } | |
651 | ||
652 | /** | |
653 | * trace_pid_show - show the current pid in seq_file processing | |
654 | * @m: The seq_file structure to write into | |
655 | * @v: A void pointer of the pid (+1) value to display | |
656 | * | |
657 | * Can be directly used by seq_file operations to display the current | |
658 | * pid value. | |
659 | */ | |
660 | int trace_pid_show(struct seq_file *m, void *v) | |
661 | { | |
662 | unsigned long pid = (unsigned long)v - 1; | |
663 | ||
664 | seq_printf(m, "%lu\n", pid); | |
665 | return 0; | |
666 | } | |
667 | ||
76c813e2 SRRH |
668 | /* 128 should be much more than enough */ |
669 | #define PID_BUF_SIZE 127 | |
670 | ||
671 | int trace_pid_write(struct trace_pid_list *filtered_pids, | |
672 | struct trace_pid_list **new_pid_list, | |
673 | const char __user *ubuf, size_t cnt) | |
674 | { | |
675 | struct trace_pid_list *pid_list; | |
676 | struct trace_parser parser; | |
677 | unsigned long val; | |
678 | int nr_pids = 0; | |
679 | ssize_t read = 0; | |
680 | ssize_t ret = 0; | |
681 | loff_t pos; | |
682 | pid_t pid; | |
683 | ||
684 | if (trace_parser_get_init(&parser, PID_BUF_SIZE + 1)) | |
685 | return -ENOMEM; | |
686 | ||
687 | /* | |
688 | * Always recreate a new array. The write is an all or nothing | |
689 | * operation. Always create a new array when adding new pids by | |
690 | * the user. If the operation fails, then the current list is | |
691 | * not modified. | |
692 | */ | |
693 | pid_list = kmalloc(sizeof(*pid_list), GFP_KERNEL); | |
91862cc7 WW |
694 | if (!pid_list) { |
695 | trace_parser_put(&parser); | |
76c813e2 | 696 | return -ENOMEM; |
91862cc7 | 697 | } |
76c813e2 SRRH |
698 | |
699 | pid_list->pid_max = READ_ONCE(pid_max); | |
700 | ||
701 | /* Only truncating will shrink pid_max */ | |
702 | if (filtered_pids && filtered_pids->pid_max > pid_list->pid_max) | |
703 | pid_list->pid_max = filtered_pids->pid_max; | |
704 | ||
705 | pid_list->pids = vzalloc((pid_list->pid_max + 7) >> 3); | |
706 | if (!pid_list->pids) { | |
91862cc7 | 707 | trace_parser_put(&parser); |
76c813e2 SRRH |
708 | kfree(pid_list); |
709 | return -ENOMEM; | |
710 | } | |
711 | ||
712 | if (filtered_pids) { | |
713 | /* copy the current bits to the new max */ | |
67f20b08 WY |
714 | for_each_set_bit(pid, filtered_pids->pids, |
715 | filtered_pids->pid_max) { | |
76c813e2 | 716 | set_bit(pid, pid_list->pids); |
76c813e2 SRRH |
717 | nr_pids++; |
718 | } | |
719 | } | |
720 | ||
721 | while (cnt > 0) { | |
722 | ||
723 | pos = 0; | |
724 | ||
725 | ret = trace_get_user(&parser, ubuf, cnt, &pos); | |
726 | if (ret < 0 || !trace_parser_loaded(&parser)) | |
727 | break; | |
728 | ||
729 | read += ret; | |
730 | ubuf += ret; | |
731 | cnt -= ret; | |
732 | ||
76c813e2 SRRH |
733 | ret = -EINVAL; |
734 | if (kstrtoul(parser.buffer, 0, &val)) | |
735 | break; | |
736 | if (val >= pid_list->pid_max) | |
737 | break; | |
738 | ||
739 | pid = (pid_t)val; | |
740 | ||
741 | set_bit(pid, pid_list->pids); | |
742 | nr_pids++; | |
743 | ||
744 | trace_parser_clear(&parser); | |
745 | ret = 0; | |
746 | } | |
747 | trace_parser_put(&parser); | |
748 | ||
749 | if (ret < 0) { | |
750 | trace_free_pid_list(pid_list); | |
751 | return ret; | |
752 | } | |
753 | ||
754 | if (!nr_pids) { | |
755 | /* Cleared the list of pids */ | |
756 | trace_free_pid_list(pid_list); | |
757 | read = ret; | |
758 | pid_list = NULL; | |
759 | } | |
760 | ||
761 | *new_pid_list = pid_list; | |
762 | ||
763 | return read; | |
764 | } | |
765 | ||
1c5eb448 | 766 | static u64 buffer_ftrace_now(struct array_buffer *buf, int cpu) |
37886f6a SR |
767 | { |
768 | u64 ts; | |
769 | ||
770 | /* Early boot up does not have a buffer yet */ | |
9457158b | 771 | if (!buf->buffer) |
37886f6a SR |
772 | return trace_clock_local(); |
773 | ||
f3ef7202 | 774 | ts = ring_buffer_time_stamp(buf->buffer); |
9457158b | 775 | ring_buffer_normalize_time_stamp(buf->buffer, cpu, &ts); |
37886f6a SR |
776 | |
777 | return ts; | |
778 | } | |
bc0c38d1 | 779 | |
a5a1d1c2 | 780 | u64 ftrace_now(int cpu) |
9457158b | 781 | { |
1c5eb448 | 782 | return buffer_ftrace_now(&global_trace.array_buffer, cpu); |
9457158b AL |
783 | } |
784 | ||
10246fa3 | 785 | /** |
b3ca59f6 | 786 | * tracing_is_enabled - Show if global_trace has been enabled |
10246fa3 SRRH |
787 | * |
788 | * Shows if the global trace has been enabled or not. It uses the | |
789 | * mirror flag "buffer_disabled" to be used in fast paths such as for | |
790 | * the irqsoff tracer. But it may be inaccurate due to races. If you | |
791 | * need to know the accurate state, use tracing_is_on() which is a little | |
792 | * slower, but accurate. | |
793 | */ | |
9036990d SR |
794 | int tracing_is_enabled(void) |
795 | { | |
10246fa3 SRRH |
796 | /* |
797 | * For quick access (irqsoff uses this in fast path), just | |
798 | * return the mirror variable of the state of the ring buffer. | |
799 | * It's a little racy, but we don't really care. | |
800 | */ | |
801 | smp_rmb(); | |
802 | return !global_trace.buffer_disabled; | |
9036990d SR |
803 | } |
804 | ||
4fcdae83 | 805 | /* |
3928a8a2 SR |
806 | * trace_buf_size is the size in bytes that is allocated |
807 | * for a buffer. Note, the number of bytes is always rounded | |
808 | * to page size. | |
3f5a54e3 SR |
809 | * |
810 | * This number is purposely set to a low number of 16384. | |
811 | * If the dump on oops happens, it will be much appreciated | |
812 | * to not have to wait for all that output. Anyway this can be | |
813 | * boot time and run time configurable. | |
4fcdae83 | 814 | */ |
3928a8a2 | 815 | #define TRACE_BUF_SIZE_DEFAULT 1441792UL /* 16384 * 88 (sizeof(entry)) */ |
3f5a54e3 | 816 | |
3928a8a2 | 817 | static unsigned long trace_buf_size = TRACE_BUF_SIZE_DEFAULT; |
bc0c38d1 | 818 | |
4fcdae83 | 819 | /* trace_types holds a link list of available tracers. */ |
bc0c38d1 | 820 | static struct tracer *trace_types __read_mostly; |
4fcdae83 | 821 | |
4fcdae83 SR |
822 | /* |
823 | * trace_types_lock is used to protect the trace_types list. | |
4fcdae83 | 824 | */ |
a8227415 | 825 | DEFINE_MUTEX(trace_types_lock); |
4fcdae83 | 826 | |
7e53bd42 LJ |
827 | /* |
828 | * serialize the access of the ring buffer | |
829 | * | |
830 | * ring buffer serializes readers, but it is low level protection. | |
831 | * The validity of the events (which returns by ring_buffer_peek() ..etc) | |
832 | * are not protected by ring buffer. | |
833 | * | |
834 | * The content of events may become garbage if we allow other process consumes | |
835 | * these events concurrently: | |
836 | * A) the page of the consumed events may become a normal page | |
f2cc020d | 837 | * (not reader page) in ring buffer, and this page will be rewritten |
7e53bd42 LJ |
838 | * by events producer. |
839 | * B) The page of the consumed events may become a page for splice_read, | |
840 | * and this page will be returned to system. | |
841 | * | |
842 | * These primitives allow multi process access to different cpu ring buffer | |
843 | * concurrently. | |
844 | * | |
845 | * These primitives don't distinguish read-only and read-consume access. | |
846 | * Multi read-only access are also serialized. | |
847 | */ | |
848 | ||
849 | #ifdef CONFIG_SMP | |
850 | static DECLARE_RWSEM(all_cpu_access_lock); | |
851 | static DEFINE_PER_CPU(struct mutex, cpu_access_lock); | |
852 | ||
853 | static inline void trace_access_lock(int cpu) | |
854 | { | |
ae3b5093 | 855 | if (cpu == RING_BUFFER_ALL_CPUS) { |
7e53bd42 LJ |
856 | /* gain it for accessing the whole ring buffer. */ |
857 | down_write(&all_cpu_access_lock); | |
858 | } else { | |
859 | /* gain it for accessing a cpu ring buffer. */ | |
860 | ||
ae3b5093 | 861 | /* Firstly block other trace_access_lock(RING_BUFFER_ALL_CPUS). */ |
7e53bd42 LJ |
862 | down_read(&all_cpu_access_lock); |
863 | ||
864 | /* Secondly block other access to this @cpu ring buffer. */ | |
865 | mutex_lock(&per_cpu(cpu_access_lock, cpu)); | |
866 | } | |
867 | } | |
868 | ||
869 | static inline void trace_access_unlock(int cpu) | |
870 | { | |
ae3b5093 | 871 | if (cpu == RING_BUFFER_ALL_CPUS) { |
7e53bd42 LJ |
872 | up_write(&all_cpu_access_lock); |
873 | } else { | |
874 | mutex_unlock(&per_cpu(cpu_access_lock, cpu)); | |
875 | up_read(&all_cpu_access_lock); | |
876 | } | |
877 | } | |
878 | ||
879 | static inline void trace_access_lock_init(void) | |
880 | { | |
881 | int cpu; | |
882 | ||
883 | for_each_possible_cpu(cpu) | |
884 | mutex_init(&per_cpu(cpu_access_lock, cpu)); | |
885 | } | |
886 | ||
887 | #else | |
888 | ||
889 | static DEFINE_MUTEX(access_lock); | |
890 | ||
891 | static inline void trace_access_lock(int cpu) | |
892 | { | |
893 | (void)cpu; | |
894 | mutex_lock(&access_lock); | |
895 | } | |
896 | ||
897 | static inline void trace_access_unlock(int cpu) | |
898 | { | |
899 | (void)cpu; | |
900 | mutex_unlock(&access_lock); | |
901 | } | |
902 | ||
903 | static inline void trace_access_lock_init(void) | |
904 | { | |
905 | } | |
906 | ||
907 | #endif | |
908 | ||
d78a4614 | 909 | #ifdef CONFIG_STACKTRACE |
13292494 | 910 | static void __ftrace_trace_stack(struct trace_buffer *buffer, |
36590c50 SAS |
911 | unsigned int trace_ctx, |
912 | int skip, struct pt_regs *regs); | |
2d34f489 | 913 | static inline void ftrace_trace_stack(struct trace_array *tr, |
13292494 | 914 | struct trace_buffer *buffer, |
36590c50 SAS |
915 | unsigned int trace_ctx, |
916 | int skip, struct pt_regs *regs); | |
ca475e83 | 917 | |
d78a4614 | 918 | #else |
13292494 | 919 | static inline void __ftrace_trace_stack(struct trace_buffer *buffer, |
36590c50 SAS |
920 | unsigned int trace_ctx, |
921 | int skip, struct pt_regs *regs) | |
d78a4614 SRRH |
922 | { |
923 | } | |
2d34f489 | 924 | static inline void ftrace_trace_stack(struct trace_array *tr, |
13292494 | 925 | struct trace_buffer *buffer, |
36590c50 SAS |
926 | unsigned long trace_ctx, |
927 | int skip, struct pt_regs *regs) | |
ca475e83 SRRH |
928 | { |
929 | } | |
930 | ||
d78a4614 SRRH |
931 | #endif |
932 | ||
3e9a8aad SRRH |
933 | static __always_inline void |
934 | trace_event_setup(struct ring_buffer_event *event, | |
36590c50 | 935 | int type, unsigned int trace_ctx) |
3e9a8aad SRRH |
936 | { |
937 | struct trace_entry *ent = ring_buffer_event_data(event); | |
938 | ||
36590c50 | 939 | tracing_generic_entry_update(ent, type, trace_ctx); |
3e9a8aad SRRH |
940 | } |
941 | ||
942 | static __always_inline struct ring_buffer_event * | |
13292494 | 943 | __trace_buffer_lock_reserve(struct trace_buffer *buffer, |
3e9a8aad SRRH |
944 | int type, |
945 | unsigned long len, | |
36590c50 | 946 | unsigned int trace_ctx) |
3e9a8aad SRRH |
947 | { |
948 | struct ring_buffer_event *event; | |
949 | ||
950 | event = ring_buffer_lock_reserve(buffer, len); | |
951 | if (event != NULL) | |
36590c50 | 952 | trace_event_setup(event, type, trace_ctx); |
3e9a8aad SRRH |
953 | |
954 | return event; | |
955 | } | |
956 | ||
2290f2c5 | 957 | void tracer_tracing_on(struct trace_array *tr) |
10246fa3 | 958 | { |
1c5eb448 SRV |
959 | if (tr->array_buffer.buffer) |
960 | ring_buffer_record_on(tr->array_buffer.buffer); | |
10246fa3 SRRH |
961 | /* |
962 | * This flag is looked at when buffers haven't been allocated | |
963 | * yet, or by some tracers (like irqsoff), that just want to | |
964 | * know if the ring buffer has been disabled, but it can handle | |
965 | * races of where it gets disabled but we still do a record. | |
966 | * As the check is in the fast path of the tracers, it is more | |
967 | * important to be fast than accurate. | |
968 | */ | |
969 | tr->buffer_disabled = 0; | |
970 | /* Make the flag seen by readers */ | |
971 | smp_wmb(); | |
972 | } | |
973 | ||
499e5470 SR |
974 | /** |
975 | * tracing_on - enable tracing buffers | |
976 | * | |
977 | * This function enables tracing buffers that may have been | |
978 | * disabled with tracing_off. | |
979 | */ | |
980 | void tracing_on(void) | |
981 | { | |
10246fa3 | 982 | tracer_tracing_on(&global_trace); |
499e5470 SR |
983 | } |
984 | EXPORT_SYMBOL_GPL(tracing_on); | |
985 | ||
52ffabe3 SRRH |
986 | |
987 | static __always_inline void | |
13292494 | 988 | __buffer_unlock_commit(struct trace_buffer *buffer, struct ring_buffer_event *event) |
52ffabe3 | 989 | { |
d914ba37 | 990 | __this_cpu_write(trace_taskinfo_save, true); |
52ffabe3 SRRH |
991 | |
992 | /* If this is the temp buffer, we need to commit fully */ | |
993 | if (this_cpu_read(trace_buffered_event) == event) { | |
994 | /* Length is in event->array[0] */ | |
995 | ring_buffer_write(buffer, event->array[0], &event->array[1]); | |
996 | /* Release the temp buffer */ | |
997 | this_cpu_dec(trace_buffered_event_cnt); | |
998 | } else | |
999 | ring_buffer_unlock_commit(buffer, event); | |
1000 | } | |
1001 | ||
09ae7234 SRRH |
1002 | /** |
1003 | * __trace_puts - write a constant string into the trace buffer. | |
1004 | * @ip: The address of the caller | |
1005 | * @str: The constant string to write | |
1006 | * @size: The size of the string. | |
1007 | */ | |
1008 | int __trace_puts(unsigned long ip, const char *str, int size) | |
1009 | { | |
1010 | struct ring_buffer_event *event; | |
13292494 | 1011 | struct trace_buffer *buffer; |
09ae7234 | 1012 | struct print_entry *entry; |
36590c50 | 1013 | unsigned int trace_ctx; |
09ae7234 | 1014 | int alloc; |
8abfb872 | 1015 | |
983f938a | 1016 | if (!(global_trace.trace_flags & TRACE_ITER_PRINTK)) |
f0160a5a J |
1017 | return 0; |
1018 | ||
3132e107 SRRH |
1019 | if (unlikely(tracing_selftest_running || tracing_disabled)) |
1020 | return 0; | |
1021 | ||
09ae7234 SRRH |
1022 | alloc = sizeof(*entry) + size + 2; /* possible \n added */ |
1023 | ||
36590c50 | 1024 | trace_ctx = tracing_gen_ctx(); |
1c5eb448 | 1025 | buffer = global_trace.array_buffer.buffer; |
82d1b815 | 1026 | ring_buffer_nest_start(buffer); |
36590c50 SAS |
1027 | event = __trace_buffer_lock_reserve(buffer, TRACE_PRINT, alloc, |
1028 | trace_ctx); | |
82d1b815 SRV |
1029 | if (!event) { |
1030 | size = 0; | |
1031 | goto out; | |
1032 | } | |
09ae7234 SRRH |
1033 | |
1034 | entry = ring_buffer_event_data(event); | |
1035 | entry->ip = ip; | |
1036 | ||
1037 | memcpy(&entry->buf, str, size); | |
1038 | ||
1039 | /* Add a newline if necessary */ | |
1040 | if (entry->buf[size - 1] != '\n') { | |
1041 | entry->buf[size] = '\n'; | |
1042 | entry->buf[size + 1] = '\0'; | |
1043 | } else | |
1044 | entry->buf[size] = '\0'; | |
1045 | ||
1046 | __buffer_unlock_commit(buffer, event); | |
36590c50 | 1047 | ftrace_trace_stack(&global_trace, buffer, trace_ctx, 4, NULL); |
82d1b815 SRV |
1048 | out: |
1049 | ring_buffer_nest_end(buffer); | |
09ae7234 SRRH |
1050 | return size; |
1051 | } | |
1052 | EXPORT_SYMBOL_GPL(__trace_puts); | |
1053 | ||
1054 | /** | |
1055 | * __trace_bputs - write the pointer to a constant string into trace buffer | |
1056 | * @ip: The address of the caller | |
1057 | * @str: The constant string to write to the buffer to | |
1058 | */ | |
1059 | int __trace_bputs(unsigned long ip, const char *str) | |
1060 | { | |
1061 | struct ring_buffer_event *event; | |
13292494 | 1062 | struct trace_buffer *buffer; |
09ae7234 | 1063 | struct bputs_entry *entry; |
36590c50 | 1064 | unsigned int trace_ctx; |
09ae7234 | 1065 | int size = sizeof(struct bputs_entry); |
82d1b815 | 1066 | int ret = 0; |
8abfb872 | 1067 | |
983f938a | 1068 | if (!(global_trace.trace_flags & TRACE_ITER_PRINTK)) |
f0160a5a J |
1069 | return 0; |
1070 | ||
3132e107 SRRH |
1071 | if (unlikely(tracing_selftest_running || tracing_disabled)) |
1072 | return 0; | |
1073 | ||
36590c50 | 1074 | trace_ctx = tracing_gen_ctx(); |
1c5eb448 | 1075 | buffer = global_trace.array_buffer.buffer; |
82d1b815 SRV |
1076 | |
1077 | ring_buffer_nest_start(buffer); | |
3e9a8aad | 1078 | event = __trace_buffer_lock_reserve(buffer, TRACE_BPUTS, size, |
36590c50 | 1079 | trace_ctx); |
09ae7234 | 1080 | if (!event) |
82d1b815 | 1081 | goto out; |
09ae7234 SRRH |
1082 | |
1083 | entry = ring_buffer_event_data(event); | |
1084 | entry->ip = ip; | |
1085 | entry->str = str; | |
1086 | ||
1087 | __buffer_unlock_commit(buffer, event); | |
36590c50 | 1088 | ftrace_trace_stack(&global_trace, buffer, trace_ctx, 4, NULL); |
09ae7234 | 1089 | |
82d1b815 SRV |
1090 | ret = 1; |
1091 | out: | |
1092 | ring_buffer_nest_end(buffer); | |
1093 | return ret; | |
09ae7234 SRRH |
1094 | } |
1095 | EXPORT_SYMBOL_GPL(__trace_bputs); | |
1096 | ||
ad909e21 | 1097 | #ifdef CONFIG_TRACER_SNAPSHOT |
192b7993 ZW |
1098 | static void tracing_snapshot_instance_cond(struct trace_array *tr, |
1099 | void *cond_data) | |
ad909e21 | 1100 | { |
ad909e21 SRRH |
1101 | struct tracer *tracer = tr->current_trace; |
1102 | unsigned long flags; | |
1103 | ||
1b22e382 SRRH |
1104 | if (in_nmi()) { |
1105 | internal_trace_puts("*** SNAPSHOT CALLED FROM NMI CONTEXT ***\n"); | |
1106 | internal_trace_puts("*** snapshot is being ignored ***\n"); | |
1107 | return; | |
1108 | } | |
1109 | ||
ad909e21 | 1110 | if (!tr->allocated_snapshot) { |
ca268da6 SRRH |
1111 | internal_trace_puts("*** SNAPSHOT NOT ALLOCATED ***\n"); |
1112 | internal_trace_puts("*** stopping trace here! ***\n"); | |
ad909e21 SRRH |
1113 | tracing_off(); |
1114 | return; | |
1115 | } | |
1116 | ||
1117 | /* Note, snapshot can not be used when the tracer uses it */ | |
1118 | if (tracer->use_max_tr) { | |
ca268da6 SRRH |
1119 | internal_trace_puts("*** LATENCY TRACER ACTIVE ***\n"); |
1120 | internal_trace_puts("*** Can not use snapshot (sorry) ***\n"); | |
ad909e21 SRRH |
1121 | return; |
1122 | } | |
1123 | ||
1124 | local_irq_save(flags); | |
a35873a0 | 1125 | update_max_tr(tr, current, smp_processor_id(), cond_data); |
ad909e21 SRRH |
1126 | local_irq_restore(flags); |
1127 | } | |
cab50379 | 1128 | |
a35873a0 TZ |
1129 | void tracing_snapshot_instance(struct trace_array *tr) |
1130 | { | |
1131 | tracing_snapshot_instance_cond(tr, NULL); | |
1132 | } | |
1133 | ||
cab50379 | 1134 | /** |
5a93bae2 | 1135 | * tracing_snapshot - take a snapshot of the current buffer. |
cab50379 SRV |
1136 | * |
1137 | * This causes a swap between the snapshot buffer and the current live | |
1138 | * tracing buffer. You can use this to take snapshots of the live | |
1139 | * trace when some condition is triggered, but continue to trace. | |
1140 | * | |
1141 | * Note, make sure to allocate the snapshot with either | |
1142 | * a tracing_snapshot_alloc(), or by doing it manually | |
1143 | * with: echo 1 > /sys/kernel/debug/tracing/snapshot | |
1144 | * | |
1145 | * If the snapshot buffer is not allocated, it will stop tracing. | |
1146 | * Basically making a permanent snapshot. | |
1147 | */ | |
1148 | void tracing_snapshot(void) | |
1149 | { | |
1150 | struct trace_array *tr = &global_trace; | |
1151 | ||
1152 | tracing_snapshot_instance(tr); | |
1153 | } | |
1b22e382 | 1154 | EXPORT_SYMBOL_GPL(tracing_snapshot); |
ad909e21 | 1155 | |
a35873a0 TZ |
1156 | /** |
1157 | * tracing_snapshot_cond - conditionally take a snapshot of the current buffer. | |
1158 | * @tr: The tracing instance to snapshot | |
1159 | * @cond_data: The data to be tested conditionally, and possibly saved | |
1160 | * | |
1161 | * This is the same as tracing_snapshot() except that the snapshot is | |
1162 | * conditional - the snapshot will only happen if the | |
1163 | * cond_snapshot.update() implementation receiving the cond_data | |
1164 | * returns true, which means that the trace array's cond_snapshot | |
1165 | * update() operation used the cond_data to determine whether the | |
1166 | * snapshot should be taken, and if it was, presumably saved it along | |
1167 | * with the snapshot. | |
1168 | */ | |
1169 | void tracing_snapshot_cond(struct trace_array *tr, void *cond_data) | |
1170 | { | |
1171 | tracing_snapshot_instance_cond(tr, cond_data); | |
1172 | } | |
1173 | EXPORT_SYMBOL_GPL(tracing_snapshot_cond); | |
1174 | ||
1175 | /** | |
1176 | * tracing_snapshot_cond_data - get the user data associated with a snapshot | |
1177 | * @tr: The tracing instance | |
1178 | * | |
1179 | * When the user enables a conditional snapshot using | |
1180 | * tracing_snapshot_cond_enable(), the user-defined cond_data is saved | |
1181 | * with the snapshot. This accessor is used to retrieve it. | |
1182 | * | |
1183 | * Should not be called from cond_snapshot.update(), since it takes | |
1184 | * the tr->max_lock lock, which the code calling | |
1185 | * cond_snapshot.update() has already done. | |
1186 | * | |
1187 | * Returns the cond_data associated with the trace array's snapshot. | |
1188 | */ | |
1189 | void *tracing_cond_snapshot_data(struct trace_array *tr) | |
1190 | { | |
1191 | void *cond_data = NULL; | |
1192 | ||
1193 | arch_spin_lock(&tr->max_lock); | |
1194 | ||
1195 | if (tr->cond_snapshot) | |
1196 | cond_data = tr->cond_snapshot->cond_data; | |
1197 | ||
1198 | arch_spin_unlock(&tr->max_lock); | |
1199 | ||
1200 | return cond_data; | |
1201 | } | |
1202 | EXPORT_SYMBOL_GPL(tracing_cond_snapshot_data); | |
1203 | ||
1c5eb448 SRV |
1204 | static int resize_buffer_duplicate_size(struct array_buffer *trace_buf, |
1205 | struct array_buffer *size_buf, int cpu_id); | |
1206 | static void set_buffer_entries(struct array_buffer *buf, unsigned long val); | |
3209cff4 | 1207 | |
2824f503 | 1208 | int tracing_alloc_snapshot_instance(struct trace_array *tr) |
3209cff4 SRRH |
1209 | { |
1210 | int ret; | |
1211 | ||
1212 | if (!tr->allocated_snapshot) { | |
1213 | ||
1214 | /* allocate spare buffer */ | |
1215 | ret = resize_buffer_duplicate_size(&tr->max_buffer, | |
1c5eb448 | 1216 | &tr->array_buffer, RING_BUFFER_ALL_CPUS); |
3209cff4 SRRH |
1217 | if (ret < 0) |
1218 | return ret; | |
1219 | ||
1220 | tr->allocated_snapshot = true; | |
1221 | } | |
1222 | ||
1223 | return 0; | |
1224 | } | |
1225 | ||
ad1438a0 | 1226 | static void free_snapshot(struct trace_array *tr) |
3209cff4 SRRH |
1227 | { |
1228 | /* | |
1229 | * We don't free the ring buffer. instead, resize it because | |
1230 | * The max_tr ring buffer has some state (e.g. ring->clock) and | |
1231 | * we want preserve it. | |
1232 | */ | |
1233 | ring_buffer_resize(tr->max_buffer.buffer, 1, RING_BUFFER_ALL_CPUS); | |
1234 | set_buffer_entries(&tr->max_buffer, 1); | |
1235 | tracing_reset_online_cpus(&tr->max_buffer); | |
1236 | tr->allocated_snapshot = false; | |
1237 | } | |
ad909e21 | 1238 | |
93e31ffb TZ |
1239 | /** |
1240 | * tracing_alloc_snapshot - allocate snapshot buffer. | |
1241 | * | |
1242 | * This only allocates the snapshot buffer if it isn't already | |
1243 | * allocated - it doesn't also take a snapshot. | |
1244 | * | |
1245 | * This is meant to be used in cases where the snapshot buffer needs | |
1246 | * to be set up for events that can't sleep but need to be able to | |
1247 | * trigger a snapshot. | |
1248 | */ | |
1249 | int tracing_alloc_snapshot(void) | |
1250 | { | |
1251 | struct trace_array *tr = &global_trace; | |
1252 | int ret; | |
1253 | ||
2824f503 | 1254 | ret = tracing_alloc_snapshot_instance(tr); |
93e31ffb TZ |
1255 | WARN_ON(ret < 0); |
1256 | ||
1257 | return ret; | |
1258 | } | |
1259 | EXPORT_SYMBOL_GPL(tracing_alloc_snapshot); | |
1260 | ||
ad909e21 | 1261 | /** |
5a93bae2 | 1262 | * tracing_snapshot_alloc - allocate and take a snapshot of the current buffer. |
ad909e21 | 1263 | * |
5a93bae2 | 1264 | * This is similar to tracing_snapshot(), but it will allocate the |
ad909e21 SRRH |
1265 | * snapshot buffer if it isn't already allocated. Use this only |
1266 | * where it is safe to sleep, as the allocation may sleep. | |
1267 | * | |
1268 | * This causes a swap between the snapshot buffer and the current live | |
1269 | * tracing buffer. You can use this to take snapshots of the live | |
1270 | * trace when some condition is triggered, but continue to trace. | |
1271 | */ | |
1272 | void tracing_snapshot_alloc(void) | |
1273 | { | |
ad909e21 SRRH |
1274 | int ret; |
1275 | ||
93e31ffb TZ |
1276 | ret = tracing_alloc_snapshot(); |
1277 | if (ret < 0) | |
3209cff4 | 1278 | return; |
ad909e21 SRRH |
1279 | |
1280 | tracing_snapshot(); | |
1281 | } | |
1b22e382 | 1282 | EXPORT_SYMBOL_GPL(tracing_snapshot_alloc); |
a35873a0 TZ |
1283 | |
1284 | /** | |
1285 | * tracing_snapshot_cond_enable - enable conditional snapshot for an instance | |
1286 | * @tr: The tracing instance | |
1287 | * @cond_data: User data to associate with the snapshot | |
1288 | * @update: Implementation of the cond_snapshot update function | |
1289 | * | |
1290 | * Check whether the conditional snapshot for the given instance has | |
1291 | * already been enabled, or if the current tracer is already using a | |
1292 | * snapshot; if so, return -EBUSY, else create a cond_snapshot and | |
1293 | * save the cond_data and update function inside. | |
1294 | * | |
1295 | * Returns 0 if successful, error otherwise. | |
1296 | */ | |
1297 | int tracing_snapshot_cond_enable(struct trace_array *tr, void *cond_data, | |
1298 | cond_update_fn_t update) | |
1299 | { | |
1300 | struct cond_snapshot *cond_snapshot; | |
1301 | int ret = 0; | |
1302 | ||
1303 | cond_snapshot = kzalloc(sizeof(*cond_snapshot), GFP_KERNEL); | |
1304 | if (!cond_snapshot) | |
1305 | return -ENOMEM; | |
1306 | ||
1307 | cond_snapshot->cond_data = cond_data; | |
1308 | cond_snapshot->update = update; | |
1309 | ||
1310 | mutex_lock(&trace_types_lock); | |
1311 | ||
1312 | ret = tracing_alloc_snapshot_instance(tr); | |
1313 | if (ret) | |
1314 | goto fail_unlock; | |
1315 | ||
1316 | if (tr->current_trace->use_max_tr) { | |
1317 | ret = -EBUSY; | |
1318 | goto fail_unlock; | |
1319 | } | |
1320 | ||
1c347a94 SRV |
1321 | /* |
1322 | * The cond_snapshot can only change to NULL without the | |
1323 | * trace_types_lock. We don't care if we race with it going | |
1324 | * to NULL, but we want to make sure that it's not set to | |
1325 | * something other than NULL when we get here, which we can | |
1326 | * do safely with only holding the trace_types_lock and not | |
1327 | * having to take the max_lock. | |
1328 | */ | |
a35873a0 TZ |
1329 | if (tr->cond_snapshot) { |
1330 | ret = -EBUSY; | |
1331 | goto fail_unlock; | |
1332 | } | |
1333 | ||
1334 | arch_spin_lock(&tr->max_lock); | |
1335 | tr->cond_snapshot = cond_snapshot; | |
1336 | arch_spin_unlock(&tr->max_lock); | |
1337 | ||
1338 | mutex_unlock(&trace_types_lock); | |
1339 | ||
1340 | return ret; | |
1341 | ||
1342 | fail_unlock: | |
1343 | mutex_unlock(&trace_types_lock); | |
1344 | kfree(cond_snapshot); | |
1345 | return ret; | |
1346 | } | |
1347 | EXPORT_SYMBOL_GPL(tracing_snapshot_cond_enable); | |
1348 | ||
1349 | /** | |
1350 | * tracing_snapshot_cond_disable - disable conditional snapshot for an instance | |
1351 | * @tr: The tracing instance | |
1352 | * | |
1353 | * Check whether the conditional snapshot for the given instance is | |
1354 | * enabled; if so, free the cond_snapshot associated with it, | |
1355 | * otherwise return -EINVAL. | |
1356 | * | |
1357 | * Returns 0 if successful, error otherwise. | |
1358 | */ | |
1359 | int tracing_snapshot_cond_disable(struct trace_array *tr) | |
1360 | { | |
1361 | int ret = 0; | |
1362 | ||
1363 | arch_spin_lock(&tr->max_lock); | |
1364 | ||
1365 | if (!tr->cond_snapshot) | |
1366 | ret = -EINVAL; | |
1367 | else { | |
1368 | kfree(tr->cond_snapshot); | |
1369 | tr->cond_snapshot = NULL; | |
1370 | } | |
1371 | ||
1372 | arch_spin_unlock(&tr->max_lock); | |
1373 | ||
1374 | return ret; | |
1375 | } | |
1376 | EXPORT_SYMBOL_GPL(tracing_snapshot_cond_disable); | |
ad909e21 SRRH |
1377 | #else |
1378 | void tracing_snapshot(void) | |
1379 | { | |
1380 | WARN_ONCE(1, "Snapshot feature not enabled, but internal snapshot used"); | |
1381 | } | |
1b22e382 | 1382 | EXPORT_SYMBOL_GPL(tracing_snapshot); |
a35873a0 TZ |
1383 | void tracing_snapshot_cond(struct trace_array *tr, void *cond_data) |
1384 | { | |
1385 | WARN_ONCE(1, "Snapshot feature not enabled, but internal conditional snapshot used"); | |
1386 | } | |
1387 | EXPORT_SYMBOL_GPL(tracing_snapshot_cond); | |
93e31ffb TZ |
1388 | int tracing_alloc_snapshot(void) |
1389 | { | |
1390 | WARN_ONCE(1, "Snapshot feature not enabled, but snapshot allocation used"); | |
1391 | return -ENODEV; | |
1392 | } | |
1393 | EXPORT_SYMBOL_GPL(tracing_alloc_snapshot); | |
ad909e21 SRRH |
1394 | void tracing_snapshot_alloc(void) |
1395 | { | |
1396 | /* Give warning */ | |
1397 | tracing_snapshot(); | |
1398 | } | |
1b22e382 | 1399 | EXPORT_SYMBOL_GPL(tracing_snapshot_alloc); |
a35873a0 TZ |
1400 | void *tracing_cond_snapshot_data(struct trace_array *tr) |
1401 | { | |
1402 | return NULL; | |
1403 | } | |
1404 | EXPORT_SYMBOL_GPL(tracing_cond_snapshot_data); | |
1405 | int tracing_snapshot_cond_enable(struct trace_array *tr, void *cond_data, cond_update_fn_t update) | |
1406 | { | |
1407 | return -ENODEV; | |
1408 | } | |
1409 | EXPORT_SYMBOL_GPL(tracing_snapshot_cond_enable); | |
1410 | int tracing_snapshot_cond_disable(struct trace_array *tr) | |
1411 | { | |
1412 | return false; | |
1413 | } | |
1414 | EXPORT_SYMBOL_GPL(tracing_snapshot_cond_disable); | |
ad909e21 SRRH |
1415 | #endif /* CONFIG_TRACER_SNAPSHOT */ |
1416 | ||
2290f2c5 | 1417 | void tracer_tracing_off(struct trace_array *tr) |
10246fa3 | 1418 | { |
1c5eb448 SRV |
1419 | if (tr->array_buffer.buffer) |
1420 | ring_buffer_record_off(tr->array_buffer.buffer); | |
10246fa3 SRRH |
1421 | /* |
1422 | * This flag is looked at when buffers haven't been allocated | |
1423 | * yet, or by some tracers (like irqsoff), that just want to | |
1424 | * know if the ring buffer has been disabled, but it can handle | |
1425 | * races of where it gets disabled but we still do a record. | |
1426 | * As the check is in the fast path of the tracers, it is more | |
1427 | * important to be fast than accurate. | |
1428 | */ | |
1429 | tr->buffer_disabled = 1; | |
1430 | /* Make the flag seen by readers */ | |
1431 | smp_wmb(); | |
1432 | } | |
1433 | ||
499e5470 SR |
1434 | /** |
1435 | * tracing_off - turn off tracing buffers | |
1436 | * | |
1437 | * This function stops the tracing buffers from recording data. | |
1438 | * It does not disable any overhead the tracers themselves may | |
1439 | * be causing. This function simply causes all recording to | |
1440 | * the ring buffers to fail. | |
1441 | */ | |
1442 | void tracing_off(void) | |
1443 | { | |
10246fa3 | 1444 | tracer_tracing_off(&global_trace); |
499e5470 SR |
1445 | } |
1446 | EXPORT_SYMBOL_GPL(tracing_off); | |
1447 | ||
de7edd31 SRRH |
1448 | void disable_trace_on_warning(void) |
1449 | { | |
c200784a SRV |
1450 | if (__disable_trace_on_warning) { |
1451 | trace_array_printk_buf(global_trace.array_buffer.buffer, _THIS_IP_, | |
1452 | "Disabling tracing due to warning\n"); | |
de7edd31 | 1453 | tracing_off(); |
c200784a | 1454 | } |
de7edd31 SRRH |
1455 | } |
1456 | ||
10246fa3 SRRH |
1457 | /** |
1458 | * tracer_tracing_is_on - show real state of ring buffer enabled | |
1459 | * @tr : the trace array to know if ring buffer is enabled | |
1460 | * | |
1461 | * Shows real state of the ring buffer if it is enabled or not. | |
1462 | */ | |
ec573508 | 1463 | bool tracer_tracing_is_on(struct trace_array *tr) |
10246fa3 | 1464 | { |
1c5eb448 SRV |
1465 | if (tr->array_buffer.buffer) |
1466 | return ring_buffer_record_is_on(tr->array_buffer.buffer); | |
10246fa3 SRRH |
1467 | return !tr->buffer_disabled; |
1468 | } | |
1469 | ||
499e5470 SR |
1470 | /** |
1471 | * tracing_is_on - show state of ring buffers enabled | |
1472 | */ | |
1473 | int tracing_is_on(void) | |
1474 | { | |
10246fa3 | 1475 | return tracer_tracing_is_on(&global_trace); |
499e5470 SR |
1476 | } |
1477 | EXPORT_SYMBOL_GPL(tracing_is_on); | |
1478 | ||
3928a8a2 | 1479 | static int __init set_buf_size(char *str) |
bc0c38d1 | 1480 | { |
3928a8a2 | 1481 | unsigned long buf_size; |
c6caeeb1 | 1482 | |
bc0c38d1 SR |
1483 | if (!str) |
1484 | return 0; | |
9d612bef | 1485 | buf_size = memparse(str, &str); |
c6caeeb1 | 1486 | /* nr_entries can not be zero */ |
9d612bef | 1487 | if (buf_size == 0) |
c6caeeb1 | 1488 | return 0; |
3928a8a2 | 1489 | trace_buf_size = buf_size; |
bc0c38d1 SR |
1490 | return 1; |
1491 | } | |
3928a8a2 | 1492 | __setup("trace_buf_size=", set_buf_size); |
bc0c38d1 | 1493 | |
0e950173 TB |
1494 | static int __init set_tracing_thresh(char *str) |
1495 | { | |
87abb3b1 | 1496 | unsigned long threshold; |
0e950173 TB |
1497 | int ret; |
1498 | ||
1499 | if (!str) | |
1500 | return 0; | |
bcd83ea6 | 1501 | ret = kstrtoul(str, 0, &threshold); |
0e950173 TB |
1502 | if (ret < 0) |
1503 | return 0; | |
87abb3b1 | 1504 | tracing_thresh = threshold * 1000; |
0e950173 TB |
1505 | return 1; |
1506 | } | |
1507 | __setup("tracing_thresh=", set_tracing_thresh); | |
1508 | ||
57f50be1 SR |
1509 | unsigned long nsecs_to_usecs(unsigned long nsecs) |
1510 | { | |
1511 | return nsecs / 1000; | |
1512 | } | |
1513 | ||
a3418a36 SRRH |
1514 | /* |
1515 | * TRACE_FLAGS is defined as a tuple matching bit masks with strings. | |
f57a4143 | 1516 | * It uses C(a, b) where 'a' is the eval (enum) name and 'b' is the string that |
a3418a36 | 1517 | * matches it. By defining "C(a, b) b", TRACE_FLAGS becomes a list |
f57a4143 | 1518 | * of strings in the order that the evals (enum) were defined. |
a3418a36 SRRH |
1519 | */ |
1520 | #undef C | |
1521 | #define C(a, b) b | |
1522 | ||
f2cc020d | 1523 | /* These must match the bit positions in trace_iterator_flags */ |
bc0c38d1 | 1524 | static const char *trace_options[] = { |
a3418a36 | 1525 | TRACE_FLAGS |
bc0c38d1 SR |
1526 | NULL |
1527 | }; | |
1528 | ||
5079f326 Z |
1529 | static struct { |
1530 | u64 (*func)(void); | |
1531 | const char *name; | |
8be0709f | 1532 | int in_ns; /* is this clock in nanoseconds? */ |
5079f326 | 1533 | } trace_clocks[] = { |
1b3e5c09 TG |
1534 | { trace_clock_local, "local", 1 }, |
1535 | { trace_clock_global, "global", 1 }, | |
1536 | { trace_clock_counter, "counter", 0 }, | |
e7fda6c4 | 1537 | { trace_clock_jiffies, "uptime", 0 }, |
1b3e5c09 TG |
1538 | { trace_clock, "perf", 1 }, |
1539 | { ktime_get_mono_fast_ns, "mono", 1 }, | |
aabfa5f2 | 1540 | { ktime_get_raw_fast_ns, "mono_raw", 1 }, |
a3ed0e43 | 1541 | { ktime_get_boot_fast_ns, "boot", 1 }, |
8cbd9cc6 | 1542 | ARCH_TRACE_CLOCKS |
5079f326 Z |
1543 | }; |
1544 | ||
860f9f6b TZ |
1545 | bool trace_clock_in_ns(struct trace_array *tr) |
1546 | { | |
1547 | if (trace_clocks[tr->clock_id].in_ns) | |
1548 | return true; | |
1549 | ||
1550 | return false; | |
1551 | } | |
1552 | ||
b63f39ea | 1553 | /* |
1554 | * trace_parser_get_init - gets the buffer for trace parser | |
1555 | */ | |
1556 | int trace_parser_get_init(struct trace_parser *parser, int size) | |
1557 | { | |
1558 | memset(parser, 0, sizeof(*parser)); | |
1559 | ||
1560 | parser->buffer = kmalloc(size, GFP_KERNEL); | |
1561 | if (!parser->buffer) | |
1562 | return 1; | |
1563 | ||
1564 | parser->size = size; | |
1565 | return 0; | |
1566 | } | |
1567 | ||
1568 | /* | |
1569 | * trace_parser_put - frees the buffer for trace parser | |
1570 | */ | |
1571 | void trace_parser_put(struct trace_parser *parser) | |
1572 | { | |
1573 | kfree(parser->buffer); | |
0e684b65 | 1574 | parser->buffer = NULL; |
b63f39ea | 1575 | } |
1576 | ||
1577 | /* | |
1578 | * trace_get_user - reads the user input string separated by space | |
1579 | * (matched by isspace(ch)) | |
1580 | * | |
1581 | * For each string found the 'struct trace_parser' is updated, | |
1582 | * and the function returns. | |
1583 | * | |
1584 | * Returns number of bytes read. | |
1585 | * | |
1586 | * See kernel/trace/trace.h for 'struct trace_parser' details. | |
1587 | */ | |
1588 | int trace_get_user(struct trace_parser *parser, const char __user *ubuf, | |
1589 | size_t cnt, loff_t *ppos) | |
1590 | { | |
1591 | char ch; | |
1592 | size_t read = 0; | |
1593 | ssize_t ret; | |
1594 | ||
1595 | if (!*ppos) | |
1596 | trace_parser_clear(parser); | |
1597 | ||
1598 | ret = get_user(ch, ubuf++); | |
1599 | if (ret) | |
1600 | goto out; | |
1601 | ||
1602 | read++; | |
1603 | cnt--; | |
1604 | ||
1605 | /* | |
1606 | * The parser is not finished with the last write, | |
1607 | * continue reading the user input without skipping spaces. | |
1608 | */ | |
1609 | if (!parser->cont) { | |
1610 | /* skip white space */ | |
1611 | while (cnt && isspace(ch)) { | |
1612 | ret = get_user(ch, ubuf++); | |
1613 | if (ret) | |
1614 | goto out; | |
1615 | read++; | |
1616 | cnt--; | |
1617 | } | |
1618 | ||
76638d96 CD |
1619 | parser->idx = 0; |
1620 | ||
b63f39ea | 1621 | /* only spaces were written */ |
921a7acd | 1622 | if (isspace(ch) || !ch) { |
b63f39ea | 1623 | *ppos += read; |
1624 | ret = read; | |
1625 | goto out; | |
1626 | } | |
b63f39ea | 1627 | } |
1628 | ||
1629 | /* read the non-space input */ | |
921a7acd | 1630 | while (cnt && !isspace(ch) && ch) { |
3c235a33 | 1631 | if (parser->idx < parser->size - 1) |
b63f39ea | 1632 | parser->buffer[parser->idx++] = ch; |
1633 | else { | |
1634 | ret = -EINVAL; | |
1635 | goto out; | |
1636 | } | |
1637 | ret = get_user(ch, ubuf++); | |
1638 | if (ret) | |
1639 | goto out; | |
1640 | read++; | |
1641 | cnt--; | |
1642 | } | |
1643 | ||
1644 | /* We either got finished input or we have to wait for another call. */ | |
921a7acd | 1645 | if (isspace(ch) || !ch) { |
b63f39ea | 1646 | parser->buffer[parser->idx] = 0; |
1647 | parser->cont = false; | |
057db848 | 1648 | } else if (parser->idx < parser->size - 1) { |
b63f39ea | 1649 | parser->cont = true; |
1650 | parser->buffer[parser->idx++] = ch; | |
f4d0706c CD |
1651 | /* Make sure the parsed string always terminates with '\0'. */ |
1652 | parser->buffer[parser->idx] = 0; | |
057db848 SR |
1653 | } else { |
1654 | ret = -EINVAL; | |
1655 | goto out; | |
b63f39ea | 1656 | } |
1657 | ||
1658 | *ppos += read; | |
1659 | ret = read; | |
1660 | ||
1661 | out: | |
1662 | return ret; | |
1663 | } | |
1664 | ||
3a161d99 | 1665 | /* TODO add a seq_buf_to_buffer() */ |
b8b94265 | 1666 | static ssize_t trace_seq_to_buffer(struct trace_seq *s, void *buf, size_t cnt) |
3c56819b EGM |
1667 | { |
1668 | int len; | |
3c56819b | 1669 | |
5ac48378 | 1670 | if (trace_seq_used(s) <= s->seq.readpos) |
3c56819b EGM |
1671 | return -EBUSY; |
1672 | ||
5ac48378 | 1673 | len = trace_seq_used(s) - s->seq.readpos; |
3c56819b EGM |
1674 | if (cnt > len) |
1675 | cnt = len; | |
3a161d99 | 1676 | memcpy(buf, s->buffer + s->seq.readpos, cnt); |
3c56819b | 1677 | |
3a161d99 | 1678 | s->seq.readpos += cnt; |
3c56819b EGM |
1679 | return cnt; |
1680 | } | |
1681 | ||
0e950173 | 1682 | unsigned long __read_mostly tracing_thresh; |
91edde2e VRB |
1683 | static const struct file_operations tracing_max_lat_fops; |
1684 | ||
1685 | #if (defined(CONFIG_TRACER_MAX_TRACE) || defined(CONFIG_HWLAT_TRACER)) && \ | |
1686 | defined(CONFIG_FSNOTIFY) | |
1687 | ||
1688 | static struct workqueue_struct *fsnotify_wq; | |
1689 | ||
1690 | static void latency_fsnotify_workfn(struct work_struct *work) | |
1691 | { | |
1692 | struct trace_array *tr = container_of(work, struct trace_array, | |
1693 | fsnotify_work); | |
82ace1ef | 1694 | fsnotify_inode(tr->d_max_latency->d_inode, FS_MODIFY); |
91edde2e VRB |
1695 | } |
1696 | ||
1697 | static void latency_fsnotify_workfn_irq(struct irq_work *iwork) | |
1698 | { | |
1699 | struct trace_array *tr = container_of(iwork, struct trace_array, | |
1700 | fsnotify_irqwork); | |
1701 | queue_work(fsnotify_wq, &tr->fsnotify_work); | |
1702 | } | |
1703 | ||
1704 | static void trace_create_maxlat_file(struct trace_array *tr, | |
1705 | struct dentry *d_tracer) | |
1706 | { | |
1707 | INIT_WORK(&tr->fsnotify_work, latency_fsnotify_workfn); | |
1708 | init_irq_work(&tr->fsnotify_irqwork, latency_fsnotify_workfn_irq); | |
1709 | tr->d_max_latency = trace_create_file("tracing_max_latency", 0644, | |
1710 | d_tracer, &tr->max_latency, | |
1711 | &tracing_max_lat_fops); | |
1712 | } | |
1713 | ||
1714 | __init static int latency_fsnotify_init(void) | |
1715 | { | |
1716 | fsnotify_wq = alloc_workqueue("tr_max_lat_wq", | |
1717 | WQ_UNBOUND | WQ_HIGHPRI, 0); | |
1718 | if (!fsnotify_wq) { | |
1719 | pr_err("Unable to allocate tr_max_lat_wq\n"); | |
1720 | return -ENOMEM; | |
1721 | } | |
1722 | return 0; | |
1723 | } | |
1724 | ||
1725 | late_initcall_sync(latency_fsnotify_init); | |
1726 | ||
1727 | void latency_fsnotify(struct trace_array *tr) | |
1728 | { | |
1729 | if (!fsnotify_wq) | |
1730 | return; | |
1731 | /* | |
1732 | * We cannot call queue_work(&tr->fsnotify_work) from here because it's | |
1733 | * possible that we are called from __schedule() or do_idle(), which | |
1734 | * could cause a deadlock. | |
1735 | */ | |
1736 | irq_work_queue(&tr->fsnotify_irqwork); | |
1737 | } | |
1738 | ||
1739 | /* | |
1740 | * (defined(CONFIG_TRACER_MAX_TRACE) || defined(CONFIG_HWLAT_TRACER)) && \ | |
1741 | * defined(CONFIG_FSNOTIFY) | |
1742 | */ | |
1743 | #else | |
1744 | ||
1745 | #define trace_create_maxlat_file(tr, d_tracer) \ | |
1746 | trace_create_file("tracing_max_latency", 0644, d_tracer, \ | |
1747 | &tr->max_latency, &tracing_max_lat_fops) | |
1748 | ||
1749 | #endif | |
0e950173 | 1750 | |
5d4a9dba | 1751 | #ifdef CONFIG_TRACER_MAX_TRACE |
5d4a9dba SR |
1752 | /* |
1753 | * Copy the new maximum trace into the separate maximum-trace | |
1754 | * structure. (this way the maximum trace is permanently saved, | |
5a93bae2 | 1755 | * for later retrieval via /sys/kernel/tracing/tracing_max_latency) |
5d4a9dba SR |
1756 | */ |
1757 | static void | |
1758 | __update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) | |
1759 | { | |
1c5eb448 SRV |
1760 | struct array_buffer *trace_buf = &tr->array_buffer; |
1761 | struct array_buffer *max_buf = &tr->max_buffer; | |
12883efb SRRH |
1762 | struct trace_array_cpu *data = per_cpu_ptr(trace_buf->data, cpu); |
1763 | struct trace_array_cpu *max_data = per_cpu_ptr(max_buf->data, cpu); | |
5d4a9dba | 1764 | |
12883efb SRRH |
1765 | max_buf->cpu = cpu; |
1766 | max_buf->time_start = data->preempt_timestamp; | |
5d4a9dba | 1767 | |
6d9b3fa5 | 1768 | max_data->saved_latency = tr->max_latency; |
8248ac05 SR |
1769 | max_data->critical_start = data->critical_start; |
1770 | max_data->critical_end = data->critical_end; | |
5d4a9dba | 1771 | |
85f726a3 | 1772 | strncpy(max_data->comm, tsk->comm, TASK_COMM_LEN); |
8248ac05 | 1773 | max_data->pid = tsk->pid; |
f17a5194 SRRH |
1774 | /* |
1775 | * If tsk == current, then use current_uid(), as that does not use | |
1776 | * RCU. The irq tracer can be called out of RCU scope. | |
1777 | */ | |
1778 | if (tsk == current) | |
1779 | max_data->uid = current_uid(); | |
1780 | else | |
1781 | max_data->uid = task_uid(tsk); | |
1782 | ||
8248ac05 SR |
1783 | max_data->nice = tsk->static_prio - 20 - MAX_RT_PRIO; |
1784 | max_data->policy = tsk->policy; | |
1785 | max_data->rt_priority = tsk->rt_priority; | |
5d4a9dba SR |
1786 | |
1787 | /* record this tasks comm */ | |
1788 | tracing_record_cmdline(tsk); | |
91edde2e | 1789 | latency_fsnotify(tr); |
5d4a9dba SR |
1790 | } |
1791 | ||
4fcdae83 SR |
1792 | /** |
1793 | * update_max_tr - snapshot all trace buffers from global_trace to max_tr | |
1794 | * @tr: tracer | |
1795 | * @tsk: the task with the latency | |
1796 | * @cpu: The cpu that initiated the trace. | |
a35873a0 | 1797 | * @cond_data: User data associated with a conditional snapshot |
4fcdae83 SR |
1798 | * |
1799 | * Flip the buffers between the @tr and the max_tr and record information | |
1800 | * about which task was the cause of this latency. | |
1801 | */ | |
e309b41d | 1802 | void |
a35873a0 TZ |
1803 | update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu, |
1804 | void *cond_data) | |
bc0c38d1 | 1805 | { |
2b6080f2 | 1806 | if (tr->stop_count) |
b8de7bd1 SR |
1807 | return; |
1808 | ||
4c11d7ae | 1809 | WARN_ON_ONCE(!irqs_disabled()); |
34600f0e | 1810 | |
45ad21ca | 1811 | if (!tr->allocated_snapshot) { |
debdd57f | 1812 | /* Only the nop tracer should hit this when disabling */ |
2b6080f2 | 1813 | WARN_ON_ONCE(tr->current_trace != &nop_trace); |
34600f0e | 1814 | return; |
debdd57f | 1815 | } |
34600f0e | 1816 | |
0b9b12c1 | 1817 | arch_spin_lock(&tr->max_lock); |
3928a8a2 | 1818 | |
1c5eb448 SRV |
1819 | /* Inherit the recordable setting from array_buffer */ |
1820 | if (ring_buffer_record_is_set_on(tr->array_buffer.buffer)) | |
73c8d894 MH |
1821 | ring_buffer_record_on(tr->max_buffer.buffer); |
1822 | else | |
1823 | ring_buffer_record_off(tr->max_buffer.buffer); | |
1824 | ||
a35873a0 TZ |
1825 | #ifdef CONFIG_TRACER_SNAPSHOT |
1826 | if (tr->cond_snapshot && !tr->cond_snapshot->update(tr, cond_data)) | |
1827 | goto out_unlock; | |
1828 | #endif | |
1c5eb448 | 1829 | swap(tr->array_buffer.buffer, tr->max_buffer.buffer); |
3928a8a2 | 1830 | |
bc0c38d1 | 1831 | __update_max_tr(tr, tsk, cpu); |
a35873a0 TZ |
1832 | |
1833 | out_unlock: | |
0b9b12c1 | 1834 | arch_spin_unlock(&tr->max_lock); |
bc0c38d1 SR |
1835 | } |
1836 | ||
1837 | /** | |
1838 | * update_max_tr_single - only copy one trace over, and reset the rest | |
c68c9ec1 JK |
1839 | * @tr: tracer |
1840 | * @tsk: task with the latency | |
1841 | * @cpu: the cpu of the buffer to copy. | |
4fcdae83 SR |
1842 | * |
1843 | * Flip the trace of a single CPU buffer between the @tr and the max_tr. | |
bc0c38d1 | 1844 | */ |
e309b41d | 1845 | void |
bc0c38d1 SR |
1846 | update_max_tr_single(struct trace_array *tr, struct task_struct *tsk, int cpu) |
1847 | { | |
3928a8a2 | 1848 | int ret; |
bc0c38d1 | 1849 | |
2b6080f2 | 1850 | if (tr->stop_count) |
b8de7bd1 SR |
1851 | return; |
1852 | ||
4c11d7ae | 1853 | WARN_ON_ONCE(!irqs_disabled()); |
6c24499f | 1854 | if (!tr->allocated_snapshot) { |
2930e04d | 1855 | /* Only the nop tracer should hit this when disabling */ |
9e8529af | 1856 | WARN_ON_ONCE(tr->current_trace != &nop_trace); |
ef710e10 | 1857 | return; |
2930e04d | 1858 | } |
ef710e10 | 1859 | |
0b9b12c1 | 1860 | arch_spin_lock(&tr->max_lock); |
bc0c38d1 | 1861 | |
1c5eb448 | 1862 | ret = ring_buffer_swap_cpu(tr->max_buffer.buffer, tr->array_buffer.buffer, cpu); |
3928a8a2 | 1863 | |
e8165dbb SR |
1864 | if (ret == -EBUSY) { |
1865 | /* | |
1866 | * We failed to swap the buffer due to a commit taking | |
1867 | * place on this CPU. We fail to record, but we reset | |
1868 | * the max trace buffer (no one writes directly to it) | |
1869 | * and flag that it failed. | |
1870 | */ | |
12883efb | 1871 | trace_array_printk_buf(tr->max_buffer.buffer, _THIS_IP_, |
e8165dbb SR |
1872 | "Failed to swap buffers due to commit in progress\n"); |
1873 | } | |
1874 | ||
e8165dbb | 1875 | WARN_ON_ONCE(ret && ret != -EAGAIN && ret != -EBUSY); |
bc0c38d1 SR |
1876 | |
1877 | __update_max_tr(tr, tsk, cpu); | |
0b9b12c1 | 1878 | arch_spin_unlock(&tr->max_lock); |
bc0c38d1 | 1879 | } |
5d4a9dba | 1880 | #endif /* CONFIG_TRACER_MAX_TRACE */ |
bc0c38d1 | 1881 | |
2c2b0a78 | 1882 | static int wait_on_pipe(struct trace_iterator *iter, int full) |
0d5c6e1c | 1883 | { |
15693458 SRRH |
1884 | /* Iterators are static, they should be filled or empty */ |
1885 | if (trace_buffer_iter(iter, iter->cpu_file)) | |
8b8b3683 | 1886 | return 0; |
0d5c6e1c | 1887 | |
1c5eb448 | 1888 | return ring_buffer_wait(iter->array_buffer->buffer, iter->cpu_file, |
e30f53aa | 1889 | full); |
0d5c6e1c SR |
1890 | } |
1891 | ||
f4e781c0 | 1892 | #ifdef CONFIG_FTRACE_STARTUP_TEST |
9afecfbb SRV |
1893 | static bool selftests_can_run; |
1894 | ||
1895 | struct trace_selftests { | |
1896 | struct list_head list; | |
1897 | struct tracer *type; | |
1898 | }; | |
1899 | ||
1900 | static LIST_HEAD(postponed_selftests); | |
1901 | ||
1902 | static int save_selftest(struct tracer *type) | |
1903 | { | |
1904 | struct trace_selftests *selftest; | |
1905 | ||
1906 | selftest = kmalloc(sizeof(*selftest), GFP_KERNEL); | |
1907 | if (!selftest) | |
1908 | return -ENOMEM; | |
1909 | ||
1910 | selftest->type = type; | |
1911 | list_add(&selftest->list, &postponed_selftests); | |
1912 | return 0; | |
1913 | } | |
1914 | ||
f4e781c0 SRRH |
1915 | static int run_tracer_selftest(struct tracer *type) |
1916 | { | |
1917 | struct trace_array *tr = &global_trace; | |
1918 | struct tracer *saved_tracer = tr->current_trace; | |
1919 | int ret; | |
0d5c6e1c | 1920 | |
f4e781c0 SRRH |
1921 | if (!type->selftest || tracing_selftest_disabled) |
1922 | return 0; | |
0d5c6e1c | 1923 | |
9afecfbb SRV |
1924 | /* |
1925 | * If a tracer registers early in boot up (before scheduling is | |
1926 | * initialized and such), then do not run its selftests yet. | |
1927 | * Instead, run it a little later in the boot process. | |
1928 | */ | |
1929 | if (!selftests_can_run) | |
1930 | return save_selftest(type); | |
1931 | ||
ee666a18 SRV |
1932 | if (!tracing_is_on()) { |
1933 | pr_warn("Selftest for tracer %s skipped due to tracing disabled\n", | |
1934 | type->name); | |
1935 | return 0; | |
1936 | } | |
1937 | ||
0d5c6e1c | 1938 | /* |
f4e781c0 SRRH |
1939 | * Run a selftest on this tracer. |
1940 | * Here we reset the trace buffer, and set the current | |
1941 | * tracer to be this tracer. The tracer can then run some | |
1942 | * internal tracing to verify that everything is in order. | |
1943 | * If we fail, we do not register this tracer. | |
0d5c6e1c | 1944 | */ |
1c5eb448 | 1945 | tracing_reset_online_cpus(&tr->array_buffer); |
0d5c6e1c | 1946 | |
f4e781c0 SRRH |
1947 | tr->current_trace = type; |
1948 | ||
1949 | #ifdef CONFIG_TRACER_MAX_TRACE | |
1950 | if (type->use_max_tr) { | |
1951 | /* If we expanded the buffers, make sure the max is expanded too */ | |
1952 | if (ring_buffer_expanded) | |
1953 | ring_buffer_resize(tr->max_buffer.buffer, trace_buf_size, | |
1954 | RING_BUFFER_ALL_CPUS); | |
1955 | tr->allocated_snapshot = true; | |
1956 | } | |
1957 | #endif | |
1958 | ||
1959 | /* the test is responsible for initializing and enabling */ | |
1960 | pr_info("Testing tracer %s: ", type->name); | |
1961 | ret = type->selftest(type, tr); | |
1962 | /* the test is responsible for resetting too */ | |
1963 | tr->current_trace = saved_tracer; | |
1964 | if (ret) { | |
1965 | printk(KERN_CONT "FAILED!\n"); | |
1966 | /* Add the warning after printing 'FAILED' */ | |
1967 | WARN_ON(1); | |
1968 | return -1; | |
1969 | } | |
1970 | /* Only reset on passing, to avoid touching corrupted buffers */ | |
1c5eb448 | 1971 | tracing_reset_online_cpus(&tr->array_buffer); |
f4e781c0 SRRH |
1972 | |
1973 | #ifdef CONFIG_TRACER_MAX_TRACE | |
1974 | if (type->use_max_tr) { | |
1975 | tr->allocated_snapshot = false; | |
0d5c6e1c | 1976 | |
f4e781c0 SRRH |
1977 | /* Shrink the max buffer again */ |
1978 | if (ring_buffer_expanded) | |
1979 | ring_buffer_resize(tr->max_buffer.buffer, 1, | |
1980 | RING_BUFFER_ALL_CPUS); | |
1981 | } | |
1982 | #endif | |
1983 | ||
1984 | printk(KERN_CONT "PASSED\n"); | |
1985 | return 0; | |
1986 | } | |
9afecfbb SRV |
1987 | |
1988 | static __init int init_trace_selftests(void) | |
1989 | { | |
1990 | struct trace_selftests *p, *n; | |
1991 | struct tracer *t, **last; | |
1992 | int ret; | |
1993 | ||
1994 | selftests_can_run = true; | |
1995 | ||
1996 | mutex_lock(&trace_types_lock); | |
1997 | ||
1998 | if (list_empty(&postponed_selftests)) | |
1999 | goto out; | |
2000 | ||
2001 | pr_info("Running postponed tracer tests:\n"); | |
2002 | ||
78041c0c | 2003 | tracing_selftest_running = true; |
9afecfbb | 2004 | list_for_each_entry_safe(p, n, &postponed_selftests, list) { |
6fc2171c AR |
2005 | /* This loop can take minutes when sanitizers are enabled, so |
2006 | * lets make sure we allow RCU processing. | |
2007 | */ | |
2008 | cond_resched(); | |
9afecfbb SRV |
2009 | ret = run_tracer_selftest(p->type); |
2010 | /* If the test fails, then warn and remove from available_tracers */ | |
2011 | if (ret < 0) { | |
2012 | WARN(1, "tracer: %s failed selftest, disabling\n", | |
2013 | p->type->name); | |
2014 | last = &trace_types; | |
2015 | for (t = trace_types; t; t = t->next) { | |
2016 | if (t == p->type) { | |
2017 | *last = t->next; | |
2018 | break; | |
2019 | } | |
2020 | last = &t->next; | |
2021 | } | |
2022 | } | |
2023 | list_del(&p->list); | |
2024 | kfree(p); | |
2025 | } | |
78041c0c | 2026 | tracing_selftest_running = false; |
9afecfbb SRV |
2027 | |
2028 | out: | |
2029 | mutex_unlock(&trace_types_lock); | |
2030 | ||
2031 | return 0; | |
2032 | } | |
b9ef0326 | 2033 | core_initcall(init_trace_selftests); |
f4e781c0 SRRH |
2034 | #else |
2035 | static inline int run_tracer_selftest(struct tracer *type) | |
2036 | { | |
2037 | return 0; | |
0d5c6e1c | 2038 | } |
f4e781c0 | 2039 | #endif /* CONFIG_FTRACE_STARTUP_TEST */ |
0d5c6e1c | 2040 | |
41d9c0be SRRH |
2041 | static void add_tracer_options(struct trace_array *tr, struct tracer *t); |
2042 | ||
a4d1e688 JW |
2043 | static void __init apply_trace_boot_options(void); |
2044 | ||
4fcdae83 SR |
2045 | /** |
2046 | * register_tracer - register a tracer with the ftrace system. | |
c68c9ec1 | 2047 | * @type: the plugin for the tracer |
4fcdae83 SR |
2048 | * |
2049 | * Register a new plugin tracer. | |
2050 | */ | |
a4d1e688 | 2051 | int __init register_tracer(struct tracer *type) |
bc0c38d1 SR |
2052 | { |
2053 | struct tracer *t; | |
bc0c38d1 SR |
2054 | int ret = 0; |
2055 | ||
2056 | if (!type->name) { | |
2057 | pr_info("Tracer must have a name\n"); | |
2058 | return -1; | |
2059 | } | |
2060 | ||
24a461d5 | 2061 | if (strlen(type->name) >= MAX_TRACER_SIZE) { |
ee6c2c1b LZ |
2062 | pr_info("Tracer has a name longer than %d\n", MAX_TRACER_SIZE); |
2063 | return -1; | |
2064 | } | |
2065 | ||
a356646a | 2066 | if (security_locked_down(LOCKDOWN_TRACEFS)) { |
ee195452 | 2067 | pr_warn("Can not register tracer %s due to lockdown\n", |
a356646a SRV |
2068 | type->name); |
2069 | return -EPERM; | |
2070 | } | |
2071 | ||
bc0c38d1 | 2072 | mutex_lock(&trace_types_lock); |
86fa2f60 | 2073 | |
8e1b82e0 FW |
2074 | tracing_selftest_running = true; |
2075 | ||
bc0c38d1 SR |
2076 | for (t = trace_types; t; t = t->next) { |
2077 | if (strcmp(type->name, t->name) == 0) { | |
2078 | /* already found */ | |
ee6c2c1b | 2079 | pr_info("Tracer %s already registered\n", |
bc0c38d1 SR |
2080 | type->name); |
2081 | ret = -1; | |
2082 | goto out; | |
2083 | } | |
2084 | } | |
2085 | ||
adf9f195 FW |
2086 | if (!type->set_flag) |
2087 | type->set_flag = &dummy_set_flag; | |
d39cdd20 CH |
2088 | if (!type->flags) { |
2089 | /*allocate a dummy tracer_flags*/ | |
2090 | type->flags = kmalloc(sizeof(*type->flags), GFP_KERNEL); | |
c8ca003b CH |
2091 | if (!type->flags) { |
2092 | ret = -ENOMEM; | |
2093 | goto out; | |
2094 | } | |
d39cdd20 CH |
2095 | type->flags->val = 0; |
2096 | type->flags->opts = dummy_tracer_opt; | |
2097 | } else | |
adf9f195 FW |
2098 | if (!type->flags->opts) |
2099 | type->flags->opts = dummy_tracer_opt; | |
6eaaa5d5 | 2100 | |
d39cdd20 CH |
2101 | /* store the tracer for __set_tracer_option */ |
2102 | type->flags->trace = type; | |
2103 | ||
f4e781c0 SRRH |
2104 | ret = run_tracer_selftest(type); |
2105 | if (ret < 0) | |
2106 | goto out; | |
60a11774 | 2107 | |
bc0c38d1 SR |
2108 | type->next = trace_types; |
2109 | trace_types = type; | |
41d9c0be | 2110 | add_tracer_options(&global_trace, type); |
60a11774 | 2111 | |
bc0c38d1 | 2112 | out: |
8e1b82e0 | 2113 | tracing_selftest_running = false; |
bc0c38d1 SR |
2114 | mutex_unlock(&trace_types_lock); |
2115 | ||
dac74940 SR |
2116 | if (ret || !default_bootup_tracer) |
2117 | goto out_unlock; | |
2118 | ||
ee6c2c1b | 2119 | if (strncmp(default_bootup_tracer, type->name, MAX_TRACER_SIZE)) |
dac74940 SR |
2120 | goto out_unlock; |
2121 | ||
2122 | printk(KERN_INFO "Starting tracer '%s'\n", type->name); | |
2123 | /* Do we want this tracer to start on bootup? */ | |
607e2ea1 | 2124 | tracing_set_tracer(&global_trace, type->name); |
dac74940 | 2125 | default_bootup_tracer = NULL; |
a4d1e688 JW |
2126 | |
2127 | apply_trace_boot_options(); | |
2128 | ||
dac74940 | 2129 | /* disable other selftests, since this will break it. */ |
60efe21e | 2130 | disable_tracing_selftest("running a tracer"); |
b2821ae6 | 2131 | |
dac74940 | 2132 | out_unlock: |
bc0c38d1 SR |
2133 | return ret; |
2134 | } | |
2135 | ||
1c5eb448 | 2136 | static void tracing_reset_cpu(struct array_buffer *buf, int cpu) |
f633903a | 2137 | { |
13292494 | 2138 | struct trace_buffer *buffer = buf->buffer; |
f633903a | 2139 | |
a5416411 HT |
2140 | if (!buffer) |
2141 | return; | |
2142 | ||
f633903a SR |
2143 | ring_buffer_record_disable(buffer); |
2144 | ||
2145 | /* Make sure all commits have finished */ | |
74401729 | 2146 | synchronize_rcu(); |
68179686 | 2147 | ring_buffer_reset_cpu(buffer, cpu); |
f633903a SR |
2148 | |
2149 | ring_buffer_record_enable(buffer); | |
2150 | } | |
2151 | ||
1c5eb448 | 2152 | void tracing_reset_online_cpus(struct array_buffer *buf) |
213cc060 | 2153 | { |
13292494 | 2154 | struct trace_buffer *buffer = buf->buffer; |
213cc060 | 2155 | |
a5416411 HT |
2156 | if (!buffer) |
2157 | return; | |
2158 | ||
621968cd SR |
2159 | ring_buffer_record_disable(buffer); |
2160 | ||
2161 | /* Make sure all commits have finished */ | |
74401729 | 2162 | synchronize_rcu(); |
621968cd | 2163 | |
9457158b | 2164 | buf->time_start = buffer_ftrace_now(buf, buf->cpu); |
213cc060 | 2165 | |
b23d7a5f | 2166 | ring_buffer_reset_online_cpus(buffer); |
621968cd SR |
2167 | |
2168 | ring_buffer_record_enable(buffer); | |
213cc060 PE |
2169 | } |
2170 | ||
09d8091c | 2171 | /* Must have trace_types_lock held */ |
873c642f | 2172 | void tracing_reset_all_online_cpus(void) |
9456f0fa | 2173 | { |
873c642f SRRH |
2174 | struct trace_array *tr; |
2175 | ||
873c642f | 2176 | list_for_each_entry(tr, &ftrace_trace_arrays, list) { |
065e63f9 SRV |
2177 | if (!tr->clear_trace) |
2178 | continue; | |
2179 | tr->clear_trace = false; | |
1c5eb448 | 2180 | tracing_reset_online_cpus(&tr->array_buffer); |
12883efb SRRH |
2181 | #ifdef CONFIG_TRACER_MAX_TRACE |
2182 | tracing_reset_online_cpus(&tr->max_buffer); | |
2183 | #endif | |
873c642f | 2184 | } |
9456f0fa SR |
2185 | } |
2186 | ||
d914ba37 JF |
2187 | static int *tgid_map; |
2188 | ||
939c7a4f | 2189 | #define SAVED_CMDLINES_DEFAULT 128 |
2c7eea4c | 2190 | #define NO_CMDLINE_MAP UINT_MAX |
edc35bd7 | 2191 | static arch_spinlock_t trace_cmdline_lock = __ARCH_SPIN_LOCK_UNLOCKED; |
939c7a4f YY |
2192 | struct saved_cmdlines_buffer { |
2193 | unsigned map_pid_to_cmdline[PID_MAX_DEFAULT+1]; | |
2194 | unsigned *map_cmdline_to_pid; | |
2195 | unsigned cmdline_num; | |
2196 | int cmdline_idx; | |
2197 | char *saved_cmdlines; | |
2198 | }; | |
2199 | static struct saved_cmdlines_buffer *savedcmd; | |
25b0b44a | 2200 | |
939c7a4f YY |
2201 | static inline char *get_saved_cmdlines(int idx) |
2202 | { | |
2203 | return &savedcmd->saved_cmdlines[idx * TASK_COMM_LEN]; | |
2204 | } | |
2205 | ||
2206 | static inline void set_cmdline(int idx, const char *cmdline) | |
bc0c38d1 | 2207 | { |
85f726a3 | 2208 | strncpy(get_saved_cmdlines(idx), cmdline, TASK_COMM_LEN); |
939c7a4f YY |
2209 | } |
2210 | ||
2211 | static int allocate_cmdlines_buffer(unsigned int val, | |
2212 | struct saved_cmdlines_buffer *s) | |
2213 | { | |
6da2ec56 KC |
2214 | s->map_cmdline_to_pid = kmalloc_array(val, |
2215 | sizeof(*s->map_cmdline_to_pid), | |
2216 | GFP_KERNEL); | |
939c7a4f YY |
2217 | if (!s->map_cmdline_to_pid) |
2218 | return -ENOMEM; | |
2219 | ||
6da2ec56 | 2220 | s->saved_cmdlines = kmalloc_array(TASK_COMM_LEN, val, GFP_KERNEL); |
939c7a4f YY |
2221 | if (!s->saved_cmdlines) { |
2222 | kfree(s->map_cmdline_to_pid); | |
2223 | return -ENOMEM; | |
2224 | } | |
2225 | ||
2226 | s->cmdline_idx = 0; | |
2227 | s->cmdline_num = val; | |
2228 | memset(&s->map_pid_to_cmdline, NO_CMDLINE_MAP, | |
2229 | sizeof(s->map_pid_to_cmdline)); | |
2230 | memset(s->map_cmdline_to_pid, NO_CMDLINE_MAP, | |
2231 | val * sizeof(*s->map_cmdline_to_pid)); | |
2232 | ||
2233 | return 0; | |
2234 | } | |
2235 | ||
2236 | static int trace_create_savedcmd(void) | |
2237 | { | |
2238 | int ret; | |
2239 | ||
a6af8fbf | 2240 | savedcmd = kmalloc(sizeof(*savedcmd), GFP_KERNEL); |
939c7a4f YY |
2241 | if (!savedcmd) |
2242 | return -ENOMEM; | |
2243 | ||
2244 | ret = allocate_cmdlines_buffer(SAVED_CMDLINES_DEFAULT, savedcmd); | |
2245 | if (ret < 0) { | |
2246 | kfree(savedcmd); | |
2247 | savedcmd = NULL; | |
2248 | return -ENOMEM; | |
2249 | } | |
2250 | ||
2251 | return 0; | |
bc0c38d1 SR |
2252 | } |
2253 | ||
b5130b1e CE |
2254 | int is_tracing_stopped(void) |
2255 | { | |
2b6080f2 | 2256 | return global_trace.stop_count; |
b5130b1e CE |
2257 | } |
2258 | ||
0f048701 SR |
2259 | /** |
2260 | * tracing_start - quick start of the tracer | |
2261 | * | |
2262 | * If tracing is enabled but was stopped by tracing_stop, | |
2263 | * this will start the tracer back up. | |
2264 | */ | |
2265 | void tracing_start(void) | |
2266 | { | |
13292494 | 2267 | struct trace_buffer *buffer; |
0f048701 SR |
2268 | unsigned long flags; |
2269 | ||
2270 | if (tracing_disabled) | |
2271 | return; | |
2272 | ||
2b6080f2 SR |
2273 | raw_spin_lock_irqsave(&global_trace.start_lock, flags); |
2274 | if (--global_trace.stop_count) { | |
2275 | if (global_trace.stop_count < 0) { | |
b06a8301 SR |
2276 | /* Someone screwed up their debugging */ |
2277 | WARN_ON_ONCE(1); | |
2b6080f2 | 2278 | global_trace.stop_count = 0; |
b06a8301 | 2279 | } |
0f048701 SR |
2280 | goto out; |
2281 | } | |
2282 | ||
a2f80714 | 2283 | /* Prevent the buffers from switching */ |
0b9b12c1 | 2284 | arch_spin_lock(&global_trace.max_lock); |
0f048701 | 2285 | |
1c5eb448 | 2286 | buffer = global_trace.array_buffer.buffer; |
0f048701 SR |
2287 | if (buffer) |
2288 | ring_buffer_record_enable(buffer); | |
2289 | ||
12883efb SRRH |
2290 | #ifdef CONFIG_TRACER_MAX_TRACE |
2291 | buffer = global_trace.max_buffer.buffer; | |
0f048701 SR |
2292 | if (buffer) |
2293 | ring_buffer_record_enable(buffer); | |
12883efb | 2294 | #endif |
0f048701 | 2295 | |
0b9b12c1 | 2296 | arch_spin_unlock(&global_trace.max_lock); |
a2f80714 | 2297 | |
0f048701 | 2298 | out: |
2b6080f2 SR |
2299 | raw_spin_unlock_irqrestore(&global_trace.start_lock, flags); |
2300 | } | |
2301 | ||
2302 | static void tracing_start_tr(struct trace_array *tr) | |
2303 | { | |
13292494 | 2304 | struct trace_buffer *buffer; |
2b6080f2 SR |
2305 | unsigned long flags; |
2306 | ||
2307 | if (tracing_disabled) | |
2308 | return; | |
2309 | ||
2310 | /* If global, we need to also start the max tracer */ | |
2311 | if (tr->flags & TRACE_ARRAY_FL_GLOBAL) | |
2312 | return tracing_start(); | |
2313 | ||
2314 | raw_spin_lock_irqsave(&tr->start_lock, flags); | |
2315 | ||
2316 | if (--tr->stop_count) { | |
2317 | if (tr->stop_count < 0) { | |
2318 | /* Someone screwed up their debugging */ | |
2319 | WARN_ON_ONCE(1); | |
2320 | tr->stop_count = 0; | |
2321 | } | |
2322 | goto out; | |
2323 | } | |
2324 | ||
1c5eb448 | 2325 | buffer = tr->array_buffer.buffer; |
2b6080f2 SR |
2326 | if (buffer) |
2327 | ring_buffer_record_enable(buffer); | |
2328 | ||
2329 | out: | |
2330 | raw_spin_unlock_irqrestore(&tr->start_lock, flags); | |
0f048701 SR |
2331 | } |
2332 | ||
2333 | /** | |
2334 | * tracing_stop - quick stop of the tracer | |
2335 | * | |
2336 | * Light weight way to stop tracing. Use in conjunction with | |
2337 | * tracing_start. | |
2338 | */ | |
2339 | void tracing_stop(void) | |
2340 | { | |
13292494 | 2341 | struct trace_buffer *buffer; |
0f048701 SR |
2342 | unsigned long flags; |
2343 | ||
2b6080f2 SR |
2344 | raw_spin_lock_irqsave(&global_trace.start_lock, flags); |
2345 | if (global_trace.stop_count++) | |
0f048701 SR |
2346 | goto out; |
2347 | ||
a2f80714 | 2348 | /* Prevent the buffers from switching */ |
0b9b12c1 | 2349 | arch_spin_lock(&global_trace.max_lock); |
a2f80714 | 2350 | |
1c5eb448 | 2351 | buffer = global_trace.array_buffer.buffer; |
0f048701 SR |
2352 | if (buffer) |
2353 | ring_buffer_record_disable(buffer); | |
2354 | ||
12883efb SRRH |
2355 | #ifdef CONFIG_TRACER_MAX_TRACE |
2356 | buffer = global_trace.max_buffer.buffer; | |
0f048701 SR |
2357 | if (buffer) |
2358 | ring_buffer_record_disable(buffer); | |
12883efb | 2359 | #endif |
0f048701 | 2360 | |
0b9b12c1 | 2361 | arch_spin_unlock(&global_trace.max_lock); |
a2f80714 | 2362 | |
0f048701 | 2363 | out: |
2b6080f2 SR |
2364 | raw_spin_unlock_irqrestore(&global_trace.start_lock, flags); |
2365 | } | |
2366 | ||
2367 | static void tracing_stop_tr(struct trace_array *tr) | |
2368 | { | |
13292494 | 2369 | struct trace_buffer *buffer; |
2b6080f2 SR |
2370 | unsigned long flags; |
2371 | ||
2372 | /* If global, we need to also stop the max tracer */ | |
2373 | if (tr->flags & TRACE_ARRAY_FL_GLOBAL) | |
2374 | return tracing_stop(); | |
2375 | ||
2376 | raw_spin_lock_irqsave(&tr->start_lock, flags); | |
2377 | if (tr->stop_count++) | |
2378 | goto out; | |
2379 | ||
1c5eb448 | 2380 | buffer = tr->array_buffer.buffer; |
2b6080f2 SR |
2381 | if (buffer) |
2382 | ring_buffer_record_disable(buffer); | |
2383 | ||
2384 | out: | |
2385 | raw_spin_unlock_irqrestore(&tr->start_lock, flags); | |
0f048701 SR |
2386 | } |
2387 | ||
379cfdac | 2388 | static int trace_save_cmdline(struct task_struct *tsk) |
bc0c38d1 | 2389 | { |
785e3c0a | 2390 | unsigned tpid, idx; |
bc0c38d1 | 2391 | |
eaf260ac JF |
2392 | /* treat recording of idle task as a success */ |
2393 | if (!tsk->pid) | |
2394 | return 1; | |
2395 | ||
785e3c0a | 2396 | tpid = tsk->pid & (PID_MAX_DEFAULT - 1); |
bc0c38d1 SR |
2397 | |
2398 | /* | |
2399 | * It's not the end of the world if we don't get | |
2400 | * the lock, but we also don't want to spin | |
2401 | * nor do we want to disable interrupts, | |
2402 | * so if we miss here, then better luck next time. | |
2403 | */ | |
0199c4e6 | 2404 | if (!arch_spin_trylock(&trace_cmdline_lock)) |
379cfdac | 2405 | return 0; |
bc0c38d1 | 2406 | |
785e3c0a | 2407 | idx = savedcmd->map_pid_to_cmdline[tpid]; |
2c7eea4c | 2408 | if (idx == NO_CMDLINE_MAP) { |
939c7a4f | 2409 | idx = (savedcmd->cmdline_idx + 1) % savedcmd->cmdline_num; |
bc0c38d1 | 2410 | |
785e3c0a | 2411 | savedcmd->map_pid_to_cmdline[tpid] = idx; |
939c7a4f | 2412 | savedcmd->cmdline_idx = idx; |
bc0c38d1 SR |
2413 | } |
2414 | ||
785e3c0a | 2415 | savedcmd->map_cmdline_to_pid[idx] = tsk->pid; |
939c7a4f | 2416 | set_cmdline(idx, tsk->comm); |
bc0c38d1 | 2417 | |
0199c4e6 | 2418 | arch_spin_unlock(&trace_cmdline_lock); |
379cfdac SRRH |
2419 | |
2420 | return 1; | |
bc0c38d1 SR |
2421 | } |
2422 | ||
4c27e756 | 2423 | static void __trace_find_cmdline(int pid, char comm[]) |
bc0c38d1 | 2424 | { |
bc0c38d1 | 2425 | unsigned map; |
785e3c0a | 2426 | int tpid; |
bc0c38d1 | 2427 | |
4ca53085 SR |
2428 | if (!pid) { |
2429 | strcpy(comm, "<idle>"); | |
2430 | return; | |
2431 | } | |
bc0c38d1 | 2432 | |
74bf4076 SR |
2433 | if (WARN_ON_ONCE(pid < 0)) { |
2434 | strcpy(comm, "<XXX>"); | |
2435 | return; | |
2436 | } | |
2437 | ||
785e3c0a SRV |
2438 | tpid = pid & (PID_MAX_DEFAULT - 1); |
2439 | map = savedcmd->map_pid_to_cmdline[tpid]; | |
2440 | if (map != NO_CMDLINE_MAP) { | |
2441 | tpid = savedcmd->map_cmdline_to_pid[map]; | |
2442 | if (tpid == pid) { | |
2443 | strlcpy(comm, get_saved_cmdlines(map), TASK_COMM_LEN); | |
2444 | return; | |
2445 | } | |
4ca53085 | 2446 | } |
785e3c0a | 2447 | strcpy(comm, "<...>"); |
4c27e756 SRRH |
2448 | } |
2449 | ||
2450 | void trace_find_cmdline(int pid, char comm[]) | |
2451 | { | |
2452 | preempt_disable(); | |
2453 | arch_spin_lock(&trace_cmdline_lock); | |
2454 | ||
2455 | __trace_find_cmdline(pid, comm); | |
bc0c38d1 | 2456 | |
0199c4e6 | 2457 | arch_spin_unlock(&trace_cmdline_lock); |
5b6045a9 | 2458 | preempt_enable(); |
bc0c38d1 SR |
2459 | } |
2460 | ||
d914ba37 JF |
2461 | int trace_find_tgid(int pid) |
2462 | { | |
2463 | if (unlikely(!tgid_map || !pid || pid > PID_MAX_DEFAULT)) | |
2464 | return 0; | |
2465 | ||
2466 | return tgid_map[pid]; | |
2467 | } | |
2468 | ||
2469 | static int trace_save_tgid(struct task_struct *tsk) | |
2470 | { | |
bd45d34d JF |
2471 | /* treat recording of idle task as a success */ |
2472 | if (!tsk->pid) | |
2473 | return 1; | |
2474 | ||
2475 | if (unlikely(!tgid_map || tsk->pid > PID_MAX_DEFAULT)) | |
d914ba37 JF |
2476 | return 0; |
2477 | ||
2478 | tgid_map[tsk->pid] = tsk->tgid; | |
2479 | return 1; | |
2480 | } | |
2481 | ||
2482 | static bool tracing_record_taskinfo_skip(int flags) | |
2483 | { | |
2484 | if (unlikely(!(flags & (TRACE_RECORD_CMDLINE | TRACE_RECORD_TGID)))) | |
2485 | return true; | |
d914ba37 JF |
2486 | if (!__this_cpu_read(trace_taskinfo_save)) |
2487 | return true; | |
2488 | return false; | |
2489 | } | |
2490 | ||
2491 | /** | |
2492 | * tracing_record_taskinfo - record the task info of a task | |
2493 | * | |
c68c9ec1 JK |
2494 | * @task: task to record |
2495 | * @flags: TRACE_RECORD_CMDLINE for recording comm | |
2496 | * TRACE_RECORD_TGID for recording tgid | |
d914ba37 JF |
2497 | */ |
2498 | void tracing_record_taskinfo(struct task_struct *task, int flags) | |
2499 | { | |
29b1a8ad JF |
2500 | bool done; |
2501 | ||
d914ba37 JF |
2502 | if (tracing_record_taskinfo_skip(flags)) |
2503 | return; | |
29b1a8ad JF |
2504 | |
2505 | /* | |
2506 | * Record as much task information as possible. If some fail, continue | |
2507 | * to try to record the others. | |
2508 | */ | |
2509 | done = !(flags & TRACE_RECORD_CMDLINE) || trace_save_cmdline(task); | |
2510 | done &= !(flags & TRACE_RECORD_TGID) || trace_save_tgid(task); | |
2511 | ||
2512 | /* If recording any information failed, retry again soon. */ | |
2513 | if (!done) | |
d914ba37 JF |
2514 | return; |
2515 | ||
2516 | __this_cpu_write(trace_taskinfo_save, false); | |
2517 | } | |
2518 | ||
2519 | /** | |
2520 | * tracing_record_taskinfo_sched_switch - record task info for sched_switch | |
2521 | * | |
c68c9ec1 JK |
2522 | * @prev: previous task during sched_switch |
2523 | * @next: next task during sched_switch | |
2524 | * @flags: TRACE_RECORD_CMDLINE for recording comm | |
2525 | * TRACE_RECORD_TGID for recording tgid | |
d914ba37 JF |
2526 | */ |
2527 | void tracing_record_taskinfo_sched_switch(struct task_struct *prev, | |
2528 | struct task_struct *next, int flags) | |
bc0c38d1 | 2529 | { |
29b1a8ad JF |
2530 | bool done; |
2531 | ||
d914ba37 JF |
2532 | if (tracing_record_taskinfo_skip(flags)) |
2533 | return; | |
2534 | ||
29b1a8ad JF |
2535 | /* |
2536 | * Record as much task information as possible. If some fail, continue | |
2537 | * to try to record the others. | |
2538 | */ | |
2539 | done = !(flags & TRACE_RECORD_CMDLINE) || trace_save_cmdline(prev); | |
2540 | done &= !(flags & TRACE_RECORD_CMDLINE) || trace_save_cmdline(next); | |
2541 | done &= !(flags & TRACE_RECORD_TGID) || trace_save_tgid(prev); | |
2542 | done &= !(flags & TRACE_RECORD_TGID) || trace_save_tgid(next); | |
bc0c38d1 | 2543 | |
29b1a8ad JF |
2544 | /* If recording any information failed, retry again soon. */ |
2545 | if (!done) | |
7ffbd48d SR |
2546 | return; |
2547 | ||
d914ba37 JF |
2548 | __this_cpu_write(trace_taskinfo_save, false); |
2549 | } | |
2550 | ||
2551 | /* Helpers to record a specific task information */ | |
2552 | void tracing_record_cmdline(struct task_struct *task) | |
2553 | { | |
2554 | tracing_record_taskinfo(task, TRACE_RECORD_CMDLINE); | |
2555 | } | |
2556 | ||
2557 | void tracing_record_tgid(struct task_struct *task) | |
2558 | { | |
2559 | tracing_record_taskinfo(task, TRACE_RECORD_TGID); | |
bc0c38d1 SR |
2560 | } |
2561 | ||
af0009fc SRV |
2562 | /* |
2563 | * Several functions return TRACE_TYPE_PARTIAL_LINE if the trace_seq | |
2564 | * overflowed, and TRACE_TYPE_HANDLED otherwise. This helper function | |
2565 | * simplifies those functions and keeps them in sync. | |
2566 | */ | |
2567 | enum print_line_t trace_handle_return(struct trace_seq *s) | |
2568 | { | |
2569 | return trace_seq_has_overflowed(s) ? | |
2570 | TRACE_TYPE_PARTIAL_LINE : TRACE_TYPE_HANDLED; | |
2571 | } | |
2572 | EXPORT_SYMBOL_GPL(trace_handle_return); | |
2573 | ||
0c02006e | 2574 | unsigned int tracing_gen_ctx_irq_test(unsigned int irqs_status) |
bc0c38d1 | 2575 | { |
0c02006e | 2576 | unsigned int trace_flags = irqs_status; |
36590c50 | 2577 | unsigned int pc; |
bc0c38d1 | 2578 | |
36590c50 | 2579 | pc = preempt_count(); |
bc0c38d1 | 2580 | |
36590c50 SAS |
2581 | if (pc & NMI_MASK) |
2582 | trace_flags |= TRACE_FLAG_NMI; | |
2583 | if (pc & HARDIRQ_MASK) | |
2584 | trace_flags |= TRACE_FLAG_HARDIRQ; | |
fe427886 | 2585 | if (in_serving_softirq()) |
36590c50 SAS |
2586 | trace_flags |= TRACE_FLAG_SOFTIRQ; |
2587 | ||
2588 | if (tif_need_resched()) | |
2589 | trace_flags |= TRACE_FLAG_NEED_RESCHED; | |
2590 | if (test_preempt_need_resched()) | |
2591 | trace_flags |= TRACE_FLAG_PREEMPT_RESCHED; | |
2592 | return (trace_flags << 16) | (pc & 0xff); | |
bc0c38d1 SR |
2593 | } |
2594 | ||
e77405ad | 2595 | struct ring_buffer_event * |
13292494 | 2596 | trace_buffer_lock_reserve(struct trace_buffer *buffer, |
e77405ad SR |
2597 | int type, |
2598 | unsigned long len, | |
36590c50 | 2599 | unsigned int trace_ctx) |
51a763dd | 2600 | { |
36590c50 | 2601 | return __trace_buffer_lock_reserve(buffer, type, len, trace_ctx); |
0fc1b09f SRRH |
2602 | } |
2603 | ||
2604 | DEFINE_PER_CPU(struct ring_buffer_event *, trace_buffered_event); | |
2605 | DEFINE_PER_CPU(int, trace_buffered_event_cnt); | |
2606 | static int trace_buffered_event_ref; | |
2607 | ||
2608 | /** | |
2609 | * trace_buffered_event_enable - enable buffering events | |
2610 | * | |
2611 | * When events are being filtered, it is quicker to use a temporary | |
2612 | * buffer to write the event data into if there's a likely chance | |
2613 | * that it will not be committed. The discard of the ring buffer | |
2614 | * is not as fast as committing, and is much slower than copying | |
2615 | * a commit. | |
2616 | * | |
2617 | * When an event is to be filtered, allocate per cpu buffers to | |
2618 | * write the event data into, and if the event is filtered and discarded | |
2619 | * it is simply dropped, otherwise, the entire data is to be committed | |
2620 | * in one shot. | |
2621 | */ | |
2622 | void trace_buffered_event_enable(void) | |
2623 | { | |
2624 | struct ring_buffer_event *event; | |
2625 | struct page *page; | |
2626 | int cpu; | |
51a763dd | 2627 | |
0fc1b09f SRRH |
2628 | WARN_ON_ONCE(!mutex_is_locked(&event_mutex)); |
2629 | ||
2630 | if (trace_buffered_event_ref++) | |
2631 | return; | |
2632 | ||
2633 | for_each_tracing_cpu(cpu) { | |
2634 | page = alloc_pages_node(cpu_to_node(cpu), | |
2635 | GFP_KERNEL | __GFP_NORETRY, 0); | |
2636 | if (!page) | |
2637 | goto failed; | |
2638 | ||
2639 | event = page_address(page); | |
2640 | memset(event, 0, sizeof(*event)); | |
2641 | ||
2642 | per_cpu(trace_buffered_event, cpu) = event; | |
2643 | ||
2644 | preempt_disable(); | |
2645 | if (cpu == smp_processor_id() && | |
b427e765 | 2646 | __this_cpu_read(trace_buffered_event) != |
0fc1b09f SRRH |
2647 | per_cpu(trace_buffered_event, cpu)) |
2648 | WARN_ON_ONCE(1); | |
2649 | preempt_enable(); | |
51a763dd ACM |
2650 | } |
2651 | ||
0fc1b09f SRRH |
2652 | return; |
2653 | failed: | |
2654 | trace_buffered_event_disable(); | |
2655 | } | |
2656 | ||
2657 | static void enable_trace_buffered_event(void *data) | |
2658 | { | |
2659 | /* Probably not needed, but do it anyway */ | |
2660 | smp_rmb(); | |
2661 | this_cpu_dec(trace_buffered_event_cnt); | |
2662 | } | |
2663 | ||
2664 | static void disable_trace_buffered_event(void *data) | |
2665 | { | |
2666 | this_cpu_inc(trace_buffered_event_cnt); | |
2667 | } | |
2668 | ||
2669 | /** | |
2670 | * trace_buffered_event_disable - disable buffering events | |
2671 | * | |
2672 | * When a filter is removed, it is faster to not use the buffered | |
2673 | * events, and to commit directly into the ring buffer. Free up | |
2674 | * the temp buffers when there are no more users. This requires | |
2675 | * special synchronization with current events. | |
2676 | */ | |
2677 | void trace_buffered_event_disable(void) | |
2678 | { | |
2679 | int cpu; | |
2680 | ||
2681 | WARN_ON_ONCE(!mutex_is_locked(&event_mutex)); | |
2682 | ||
2683 | if (WARN_ON_ONCE(!trace_buffered_event_ref)) | |
2684 | return; | |
2685 | ||
2686 | if (--trace_buffered_event_ref) | |
2687 | return; | |
2688 | ||
2689 | preempt_disable(); | |
2690 | /* For each CPU, set the buffer as used. */ | |
2691 | smp_call_function_many(tracing_buffer_mask, | |
2692 | disable_trace_buffered_event, NULL, 1); | |
2693 | preempt_enable(); | |
2694 | ||
2695 | /* Wait for all current users to finish */ | |
74401729 | 2696 | synchronize_rcu(); |
0fc1b09f SRRH |
2697 | |
2698 | for_each_tracing_cpu(cpu) { | |
2699 | free_page((unsigned long)per_cpu(trace_buffered_event, cpu)); | |
2700 | per_cpu(trace_buffered_event, cpu) = NULL; | |
2701 | } | |
2702 | /* | |
2703 | * Make sure trace_buffered_event is NULL before clearing | |
2704 | * trace_buffered_event_cnt. | |
2705 | */ | |
2706 | smp_wmb(); | |
2707 | ||
2708 | preempt_disable(); | |
2709 | /* Do the work on each cpu */ | |
2710 | smp_call_function_many(tracing_buffer_mask, | |
2711 | enable_trace_buffered_event, NULL, 1); | |
2712 | preempt_enable(); | |
51a763dd | 2713 | } |
51a763dd | 2714 | |
13292494 | 2715 | static struct trace_buffer *temp_buffer; |
2c4a33ab | 2716 | |
ccb469a1 | 2717 | struct ring_buffer_event * |
13292494 | 2718 | trace_event_buffer_lock_reserve(struct trace_buffer **current_rb, |
7f1d2f82 | 2719 | struct trace_event_file *trace_file, |
ccb469a1 | 2720 | int type, unsigned long len, |
36590c50 | 2721 | unsigned int trace_ctx) |
ccb469a1 | 2722 | { |
2c4a33ab | 2723 | struct ring_buffer_event *entry; |
b94bc80d | 2724 | struct trace_array *tr = trace_file->tr; |
0fc1b09f | 2725 | int val; |
2c4a33ab | 2726 | |
b94bc80d | 2727 | *current_rb = tr->array_buffer.buffer; |
0fc1b09f | 2728 | |
b94bc80d SRV |
2729 | if (!tr->no_filter_buffering_ref && |
2730 | (trace_file->flags & (EVENT_FILE_FL_SOFT_DISABLED | EVENT_FILE_FL_FILTERED)) && | |
0fc1b09f SRRH |
2731 | (entry = this_cpu_read(trace_buffered_event))) { |
2732 | /* Try to use the per cpu buffer first */ | |
2733 | val = this_cpu_inc_return(trace_buffered_event_cnt); | |
3e08a9f9 | 2734 | if ((len < (PAGE_SIZE - sizeof(*entry) - sizeof(entry->array[0]))) && val == 1) { |
36590c50 | 2735 | trace_event_setup(entry, type, trace_ctx); |
0fc1b09f SRRH |
2736 | entry->array[0] = len; |
2737 | return entry; | |
2738 | } | |
2739 | this_cpu_dec(trace_buffered_event_cnt); | |
2740 | } | |
2741 | ||
36590c50 SAS |
2742 | entry = __trace_buffer_lock_reserve(*current_rb, type, len, |
2743 | trace_ctx); | |
2c4a33ab SRRH |
2744 | /* |
2745 | * If tracing is off, but we have triggers enabled | |
2746 | * we still need to look at the event data. Use the temp_buffer | |
906695e5 | 2747 | * to store the trace event for the trigger to use. It's recursive |
2c4a33ab SRRH |
2748 | * safe and will not be recorded anywhere. |
2749 | */ | |
5d6ad960 | 2750 | if (!entry && trace_file->flags & EVENT_FILE_FL_TRIGGER_COND) { |
2c4a33ab | 2751 | *current_rb = temp_buffer; |
36590c50 SAS |
2752 | entry = __trace_buffer_lock_reserve(*current_rb, type, len, |
2753 | trace_ctx); | |
2c4a33ab SRRH |
2754 | } |
2755 | return entry; | |
ccb469a1 SR |
2756 | } |
2757 | EXPORT_SYMBOL_GPL(trace_event_buffer_lock_reserve); | |
2758 | ||
42391745 SRRH |
2759 | static DEFINE_SPINLOCK(tracepoint_iter_lock); |
2760 | static DEFINE_MUTEX(tracepoint_printk_mutex); | |
2761 | ||
2762 | static void output_printk(struct trace_event_buffer *fbuffer) | |
2763 | { | |
2764 | struct trace_event_call *event_call; | |
d8d0c245 | 2765 | struct trace_event_file *file; |
42391745 SRRH |
2766 | struct trace_event *event; |
2767 | unsigned long flags; | |
2768 | struct trace_iterator *iter = tracepoint_print_iter; | |
2769 | ||
2770 | /* We should never get here if iter is NULL */ | |
2771 | if (WARN_ON_ONCE(!iter)) | |
2772 | return; | |
2773 | ||
2774 | event_call = fbuffer->trace_file->event_call; | |
2775 | if (!event_call || !event_call->event.funcs || | |
2776 | !event_call->event.funcs->trace) | |
2777 | return; | |
2778 | ||
d8d0c245 MH |
2779 | file = fbuffer->trace_file; |
2780 | if (test_bit(EVENT_FILE_FL_SOFT_DISABLED_BIT, &file->flags) || | |
2781 | (unlikely(file->flags & EVENT_FILE_FL_FILTERED) && | |
2782 | !filter_match_preds(file->filter, fbuffer->entry))) | |
2783 | return; | |
2784 | ||
42391745 SRRH |
2785 | event = &fbuffer->trace_file->event_call->event; |
2786 | ||
2787 | spin_lock_irqsave(&tracepoint_iter_lock, flags); | |
2788 | trace_seq_init(&iter->seq); | |
2789 | iter->ent = fbuffer->entry; | |
2790 | event_call->event.funcs->trace(iter, 0, event); | |
2791 | trace_seq_putc(&iter->seq, 0); | |
2792 | printk("%s", iter->seq.buffer); | |
2793 | ||
2794 | spin_unlock_irqrestore(&tracepoint_iter_lock, flags); | |
2795 | } | |
2796 | ||
2797 | int tracepoint_printk_sysctl(struct ctl_table *table, int write, | |
32927393 | 2798 | void *buffer, size_t *lenp, |
42391745 SRRH |
2799 | loff_t *ppos) |
2800 | { | |
2801 | int save_tracepoint_printk; | |
2802 | int ret; | |
2803 | ||
2804 | mutex_lock(&tracepoint_printk_mutex); | |
2805 | save_tracepoint_printk = tracepoint_printk; | |
2806 | ||
2807 | ret = proc_dointvec(table, write, buffer, lenp, ppos); | |
2808 | ||
2809 | /* | |
2810 | * This will force exiting early, as tracepoint_printk | |
2811 | * is always zero when tracepoint_printk_iter is not allocated | |
2812 | */ | |
2813 | if (!tracepoint_print_iter) | |
2814 | tracepoint_printk = 0; | |
2815 | ||
2816 | if (save_tracepoint_printk == tracepoint_printk) | |
2817 | goto out; | |
2818 | ||
2819 | if (tracepoint_printk) | |
2820 | static_key_enable(&tracepoint_printk_key.key); | |
2821 | else | |
2822 | static_key_disable(&tracepoint_printk_key.key); | |
2823 | ||
2824 | out: | |
2825 | mutex_unlock(&tracepoint_printk_mutex); | |
2826 | ||
2827 | return ret; | |
2828 | } | |
2829 | ||
2830 | void trace_event_buffer_commit(struct trace_event_buffer *fbuffer) | |
2831 | { | |
2832 | if (static_key_false(&tracepoint_printk_key.key)) | |
2833 | output_printk(fbuffer); | |
2834 | ||
8ab7a2b7 TZ |
2835 | if (static_branch_unlikely(&trace_event_exports_enabled)) |
2836 | ftrace_exports(fbuffer->event, TRACE_EXPORT_EVENT); | |
8cfcf155 | 2837 | event_trigger_unlock_commit_regs(fbuffer->trace_file, fbuffer->buffer, |
42391745 | 2838 | fbuffer->event, fbuffer->entry, |
36590c50 | 2839 | fbuffer->trace_ctx, fbuffer->regs); |
42391745 SRRH |
2840 | } |
2841 | EXPORT_SYMBOL_GPL(trace_event_buffer_commit); | |
2842 | ||
2ee5b92a SRV |
2843 | /* |
2844 | * Skip 3: | |
2845 | * | |
2846 | * trace_buffer_unlock_commit_regs() | |
2847 | * trace_event_buffer_commit() | |
2848 | * trace_event_raw_event_xxx() | |
13cf912b | 2849 | */ |
2ee5b92a SRV |
2850 | # define STACK_SKIP 3 |
2851 | ||
b7f0c959 | 2852 | void trace_buffer_unlock_commit_regs(struct trace_array *tr, |
13292494 | 2853 | struct trace_buffer *buffer, |
0d5c6e1c | 2854 | struct ring_buffer_event *event, |
36590c50 | 2855 | unsigned int trace_ctx, |
0d5c6e1c | 2856 | struct pt_regs *regs) |
1fd8df2c | 2857 | { |
7ffbd48d | 2858 | __buffer_unlock_commit(buffer, event); |
1fd8df2c | 2859 | |
be54f69c | 2860 | /* |
2ee5b92a | 2861 | * If regs is not set, then skip the necessary functions. |
be54f69c SRRH |
2862 | * Note, we can still get here via blktrace, wakeup tracer |
2863 | * and mmiotrace, but that's ok if they lose a function or | |
2ee5b92a | 2864 | * two. They are not that meaningful. |
be54f69c | 2865 | */ |
36590c50 SAS |
2866 | ftrace_trace_stack(tr, buffer, trace_ctx, regs ? 0 : STACK_SKIP, regs); |
2867 | ftrace_trace_userstack(tr, buffer, trace_ctx); | |
1fd8df2c | 2868 | } |
1fd8df2c | 2869 | |
52ffabe3 SRRH |
2870 | /* |
2871 | * Similar to trace_buffer_unlock_commit_regs() but do not dump stack. | |
2872 | */ | |
2873 | void | |
13292494 | 2874 | trace_buffer_unlock_commit_nostack(struct trace_buffer *buffer, |
52ffabe3 SRRH |
2875 | struct ring_buffer_event *event) |
2876 | { | |
2877 | __buffer_unlock_commit(buffer, event); | |
2878 | } | |
2879 | ||
e309b41d | 2880 | void |
36590c50 SAS |
2881 | trace_function(struct trace_array *tr, unsigned long ip, unsigned long |
2882 | parent_ip, unsigned int trace_ctx) | |
bc0c38d1 | 2883 | { |
2425bcb9 | 2884 | struct trace_event_call *call = &event_function; |
13292494 | 2885 | struct trace_buffer *buffer = tr->array_buffer.buffer; |
3928a8a2 | 2886 | struct ring_buffer_event *event; |
777e208d | 2887 | struct ftrace_entry *entry; |
bc0c38d1 | 2888 | |
3e9a8aad | 2889 | event = __trace_buffer_lock_reserve(buffer, TRACE_FN, sizeof(*entry), |
36590c50 | 2890 | trace_ctx); |
3928a8a2 SR |
2891 | if (!event) |
2892 | return; | |
2893 | entry = ring_buffer_event_data(event); | |
777e208d SR |
2894 | entry->ip = ip; |
2895 | entry->parent_ip = parent_ip; | |
e1112b4d | 2896 | |
478409dd | 2897 | if (!call_filter_check_discard(call, entry, buffer, event)) { |
8438f521 TZ |
2898 | if (static_branch_unlikely(&trace_function_exports_enabled)) |
2899 | ftrace_exports(event, TRACE_EXPORT_FUNCTION); | |
7ffbd48d | 2900 | __buffer_unlock_commit(buffer, event); |
478409dd | 2901 | } |
bc0c38d1 SR |
2902 | } |
2903 | ||
c0a0d0d3 | 2904 | #ifdef CONFIG_STACKTRACE |
4a9bd3f1 | 2905 | |
2a820bf7 TG |
2906 | /* Allow 4 levels of nesting: normal, softirq, irq, NMI */ |
2907 | #define FTRACE_KSTACK_NESTING 4 | |
2908 | ||
2909 | #define FTRACE_KSTACK_ENTRIES (PAGE_SIZE / FTRACE_KSTACK_NESTING) | |
2910 | ||
4a9bd3f1 | 2911 | struct ftrace_stack { |
2a820bf7 | 2912 | unsigned long calls[FTRACE_KSTACK_ENTRIES]; |
4a9bd3f1 SR |
2913 | }; |
2914 | ||
2a820bf7 TG |
2915 | |
2916 | struct ftrace_stacks { | |
2917 | struct ftrace_stack stacks[FTRACE_KSTACK_NESTING]; | |
4a9bd3f1 SR |
2918 | }; |
2919 | ||
2a820bf7 | 2920 | static DEFINE_PER_CPU(struct ftrace_stacks, ftrace_stacks); |
4a9bd3f1 SR |
2921 | static DEFINE_PER_CPU(int, ftrace_stack_reserve); |
2922 | ||
13292494 | 2923 | static void __ftrace_trace_stack(struct trace_buffer *buffer, |
36590c50 SAS |
2924 | unsigned int trace_ctx, |
2925 | int skip, struct pt_regs *regs) | |
86387f7e | 2926 | { |
2425bcb9 | 2927 | struct trace_event_call *call = &event_kernel_stack; |
3928a8a2 | 2928 | struct ring_buffer_event *event; |
ee6dd0db | 2929 | unsigned int size, nr_entries; |
2a820bf7 | 2930 | struct ftrace_stack *fstack; |
777e208d | 2931 | struct stack_entry *entry; |
2a820bf7 | 2932 | int stackidx; |
4a9bd3f1 | 2933 | |
be54f69c | 2934 | /* |
2ee5b92a | 2935 | * Add one, for this function and the call to save_stack_trace() |
be54f69c SRRH |
2936 | * If regs is set, then these functions will not be in the way. |
2937 | */ | |
2ee5b92a | 2938 | #ifndef CONFIG_UNWINDER_ORC |
be54f69c | 2939 | if (!regs) |
ee6dd0db | 2940 | skip++; |
2ee5b92a | 2941 | #endif |
be54f69c | 2942 | |
4a9bd3f1 SR |
2943 | preempt_disable_notrace(); |
2944 | ||
2a820bf7 TG |
2945 | stackidx = __this_cpu_inc_return(ftrace_stack_reserve) - 1; |
2946 | ||
2947 | /* This should never happen. If it does, yell once and skip */ | |
906695e5 | 2948 | if (WARN_ON_ONCE(stackidx >= FTRACE_KSTACK_NESTING)) |
2a820bf7 TG |
2949 | goto out; |
2950 | ||
4a9bd3f1 | 2951 | /* |
2a820bf7 TG |
2952 | * The above __this_cpu_inc_return() is 'atomic' cpu local. An |
2953 | * interrupt will either see the value pre increment or post | |
2954 | * increment. If the interrupt happens pre increment it will have | |
2955 | * restored the counter when it returns. We just need a barrier to | |
2956 | * keep gcc from moving things around. | |
4a9bd3f1 SR |
2957 | */ |
2958 | barrier(); | |
4a9bd3f1 | 2959 | |
2a820bf7 | 2960 | fstack = this_cpu_ptr(ftrace_stacks.stacks) + stackidx; |
ee6dd0db | 2961 | size = ARRAY_SIZE(fstack->calls); |
4a9bd3f1 | 2962 | |
ee6dd0db TG |
2963 | if (regs) { |
2964 | nr_entries = stack_trace_save_regs(regs, fstack->calls, | |
2965 | size, skip); | |
2966 | } else { | |
2967 | nr_entries = stack_trace_save(fstack->calls, size, skip); | |
2968 | } | |
86387f7e | 2969 | |
ee6dd0db | 2970 | size = nr_entries * sizeof(unsigned long); |
3e9a8aad | 2971 | event = __trace_buffer_lock_reserve(buffer, TRACE_STACK, |
9deb193a SRV |
2972 | (sizeof(*entry) - sizeof(entry->caller)) + size, |
2973 | trace_ctx); | |
3928a8a2 | 2974 | if (!event) |
4a9bd3f1 SR |
2975 | goto out; |
2976 | entry = ring_buffer_event_data(event); | |
86387f7e | 2977 | |
ee6dd0db TG |
2978 | memcpy(&entry->caller, fstack->calls, size); |
2979 | entry->size = nr_entries; | |
86387f7e | 2980 | |
f306cc82 | 2981 | if (!call_filter_check_discard(call, entry, buffer, event)) |
7ffbd48d | 2982 | __buffer_unlock_commit(buffer, event); |
4a9bd3f1 SR |
2983 | |
2984 | out: | |
2985 | /* Again, don't let gcc optimize things here */ | |
2986 | barrier(); | |
82146529 | 2987 | __this_cpu_dec(ftrace_stack_reserve); |
4a9bd3f1 SR |
2988 | preempt_enable_notrace(); |
2989 | ||
f0a920d5 IM |
2990 | } |
2991 | ||
2d34f489 | 2992 | static inline void ftrace_trace_stack(struct trace_array *tr, |
13292494 | 2993 | struct trace_buffer *buffer, |
36590c50 SAS |
2994 | unsigned int trace_ctx, |
2995 | int skip, struct pt_regs *regs) | |
53614991 | 2996 | { |
2d34f489 | 2997 | if (!(tr->trace_flags & TRACE_ITER_STACKTRACE)) |
53614991 SR |
2998 | return; |
2999 | ||
36590c50 | 3000 | __ftrace_trace_stack(buffer, trace_ctx, skip, regs); |
53614991 SR |
3001 | } |
3002 | ||
36590c50 SAS |
3003 | void __trace_stack(struct trace_array *tr, unsigned int trace_ctx, |
3004 | int skip) | |
38697053 | 3005 | { |
13292494 | 3006 | struct trace_buffer *buffer = tr->array_buffer.buffer; |
a33d7d94 SRV |
3007 | |
3008 | if (rcu_is_watching()) { | |
36590c50 | 3009 | __ftrace_trace_stack(buffer, trace_ctx, skip, NULL); |
a33d7d94 SRV |
3010 | return; |
3011 | } | |
3012 | ||
3013 | /* | |
3014 | * When an NMI triggers, RCU is enabled via rcu_nmi_enter(), | |
3015 | * but if the above rcu_is_watching() failed, then the NMI | |
3016 | * triggered someplace critical, and rcu_irq_enter() should | |
3017 | * not be called from NMI. | |
3018 | */ | |
3019 | if (unlikely(in_nmi())) | |
3020 | return; | |
3021 | ||
a33d7d94 | 3022 | rcu_irq_enter_irqson(); |
36590c50 | 3023 | __ftrace_trace_stack(buffer, trace_ctx, skip, NULL); |
a33d7d94 | 3024 | rcu_irq_exit_irqson(); |
38697053 SR |
3025 | } |
3026 | ||
03889384 SR |
3027 | /** |
3028 | * trace_dump_stack - record a stack back trace in the trace buffer | |
c142be8e | 3029 | * @skip: Number of functions to skip (helper handlers) |
03889384 | 3030 | */ |
c142be8e | 3031 | void trace_dump_stack(int skip) |
03889384 | 3032 | { |
03889384 | 3033 | if (tracing_disabled || tracing_selftest_running) |
e36c5458 | 3034 | return; |
03889384 | 3035 | |
2ee5b92a SRV |
3036 | #ifndef CONFIG_UNWINDER_ORC |
3037 | /* Skip 1 to skip this function. */ | |
3038 | skip++; | |
3039 | #endif | |
1c5eb448 | 3040 | __ftrace_trace_stack(global_trace.array_buffer.buffer, |
36590c50 | 3041 | tracing_gen_ctx(), skip, NULL); |
03889384 | 3042 | } |
da387e5c | 3043 | EXPORT_SYMBOL_GPL(trace_dump_stack); |
03889384 | 3044 | |
c438f140 | 3045 | #ifdef CONFIG_USER_STACKTRACE_SUPPORT |
91e86e56 SR |
3046 | static DEFINE_PER_CPU(int, user_stack_count); |
3047 | ||
c438f140 | 3048 | static void |
bcee5278 | 3049 | ftrace_trace_userstack(struct trace_array *tr, |
36590c50 | 3050 | struct trace_buffer *buffer, unsigned int trace_ctx) |
02b67518 | 3051 | { |
2425bcb9 | 3052 | struct trace_event_call *call = &event_user_stack; |
8d7c6a96 | 3053 | struct ring_buffer_event *event; |
02b67518 | 3054 | struct userstack_entry *entry; |
02b67518 | 3055 | |
bcee5278 | 3056 | if (!(tr->trace_flags & TRACE_ITER_USERSTACKTRACE)) |
02b67518 TE |
3057 | return; |
3058 | ||
b6345879 SR |
3059 | /* |
3060 | * NMIs can not handle page faults, even with fix ups. | |
3061 | * The save user stack can (and often does) fault. | |
3062 | */ | |
3063 | if (unlikely(in_nmi())) | |
3064 | return; | |
02b67518 | 3065 | |
91e86e56 SR |
3066 | /* |
3067 | * prevent recursion, since the user stack tracing may | |
3068 | * trigger other kernel events. | |
3069 | */ | |
3070 | preempt_disable(); | |
3071 | if (__this_cpu_read(user_stack_count)) | |
3072 | goto out; | |
3073 | ||
3074 | __this_cpu_inc(user_stack_count); | |
3075 | ||
3e9a8aad | 3076 | event = __trace_buffer_lock_reserve(buffer, TRACE_USER_STACK, |
36590c50 | 3077 | sizeof(*entry), trace_ctx); |
02b67518 | 3078 | if (!event) |
1dbd1951 | 3079 | goto out_drop_count; |
02b67518 | 3080 | entry = ring_buffer_event_data(event); |
02b67518 | 3081 | |
48659d31 | 3082 | entry->tgid = current->tgid; |
02b67518 TE |
3083 | memset(&entry->caller, 0, sizeof(entry->caller)); |
3084 | ||
ee6dd0db | 3085 | stack_trace_save_user(entry->caller, FTRACE_STACK_ENTRIES); |
f306cc82 | 3086 | if (!call_filter_check_discard(call, entry, buffer, event)) |
7ffbd48d | 3087 | __buffer_unlock_commit(buffer, event); |
91e86e56 | 3088 | |
1dbd1951 | 3089 | out_drop_count: |
91e86e56 | 3090 | __this_cpu_dec(user_stack_count); |
91e86e56 SR |
3091 | out: |
3092 | preempt_enable(); | |
02b67518 | 3093 | } |
c438f140 | 3094 | #else /* CONFIG_USER_STACKTRACE_SUPPORT */ |
bcee5278 SRV |
3095 | static void ftrace_trace_userstack(struct trace_array *tr, |
3096 | struct trace_buffer *buffer, | |
36590c50 | 3097 | unsigned int trace_ctx) |
02b67518 | 3098 | { |
02b67518 | 3099 | } |
c438f140 | 3100 | #endif /* !CONFIG_USER_STACKTRACE_SUPPORT */ |
02b67518 | 3101 | |
c0a0d0d3 FW |
3102 | #endif /* CONFIG_STACKTRACE */ |
3103 | ||
c658797f YKV |
3104 | static inline void |
3105 | func_repeats_set_delta_ts(struct func_repeats_entry *entry, | |
3106 | unsigned long long delta) | |
3107 | { | |
3108 | entry->bottom_delta_ts = delta & U32_MAX; | |
3109 | entry->top_delta_ts = (delta >> 32); | |
3110 | } | |
3111 | ||
3112 | void trace_last_func_repeats(struct trace_array *tr, | |
3113 | struct trace_func_repeats *last_info, | |
3114 | unsigned int trace_ctx) | |
3115 | { | |
3116 | struct trace_buffer *buffer = tr->array_buffer.buffer; | |
3117 | struct func_repeats_entry *entry; | |
3118 | struct ring_buffer_event *event; | |
3119 | u64 delta; | |
3120 | ||
3121 | event = __trace_buffer_lock_reserve(buffer, TRACE_FUNC_REPEATS, | |
3122 | sizeof(*entry), trace_ctx); | |
3123 | if (!event) | |
3124 | return; | |
3125 | ||
3126 | delta = ring_buffer_event_time_stamp(buffer, event) - | |
3127 | last_info->ts_last_call; | |
3128 | ||
3129 | entry = ring_buffer_event_data(event); | |
3130 | entry->ip = last_info->ip; | |
3131 | entry->parent_ip = last_info->parent_ip; | |
3132 | entry->count = last_info->count; | |
3133 | func_repeats_set_delta_ts(entry, delta); | |
3134 | ||
3135 | __buffer_unlock_commit(buffer, event); | |
3136 | } | |
3137 | ||
07d777fe SR |
3138 | /* created for use with alloc_percpu */ |
3139 | struct trace_buffer_struct { | |
e2ace001 AL |
3140 | int nesting; |
3141 | char buffer[4][TRACE_BUF_SIZE]; | |
07d777fe SR |
3142 | }; |
3143 | ||
3144 | static struct trace_buffer_struct *trace_percpu_buffer; | |
07d777fe SR |
3145 | |
3146 | /* | |
2b5894cc | 3147 | * This allows for lockless recording. If we're nested too deeply, then |
e2ace001 | 3148 | * this returns NULL. |
07d777fe SR |
3149 | */ |
3150 | static char *get_trace_buf(void) | |
3151 | { | |
e2ace001 | 3152 | struct trace_buffer_struct *buffer = this_cpu_ptr(trace_percpu_buffer); |
07d777fe | 3153 | |
e2ace001 | 3154 | if (!buffer || buffer->nesting >= 4) |
07d777fe SR |
3155 | return NULL; |
3156 | ||
3d9622c1 SRV |
3157 | buffer->nesting++; |
3158 | ||
3159 | /* Interrupts must see nesting incremented before we use the buffer */ | |
3160 | barrier(); | |
c1acb4ac | 3161 | return &buffer->buffer[buffer->nesting - 1][0]; |
e2ace001 AL |
3162 | } |
3163 | ||
3164 | static void put_trace_buf(void) | |
3165 | { | |
3d9622c1 SRV |
3166 | /* Don't let the decrement of nesting leak before this */ |
3167 | barrier(); | |
e2ace001 | 3168 | this_cpu_dec(trace_percpu_buffer->nesting); |
07d777fe SR |
3169 | } |
3170 | ||
3171 | static int alloc_percpu_trace_buffer(void) | |
3172 | { | |
3173 | struct trace_buffer_struct *buffers; | |
07d777fe | 3174 | |
38ce2a9e SRV |
3175 | if (trace_percpu_buffer) |
3176 | return 0; | |
3177 | ||
07d777fe | 3178 | buffers = alloc_percpu(struct trace_buffer_struct); |
24589e3a | 3179 | if (MEM_FAIL(!buffers, "Could not allocate percpu trace_printk buffer")) |
e2ace001 | 3180 | return -ENOMEM; |
07d777fe SR |
3181 | |
3182 | trace_percpu_buffer = buffers; | |
07d777fe | 3183 | return 0; |
07d777fe SR |
3184 | } |
3185 | ||
81698831 SR |
3186 | static int buffers_allocated; |
3187 | ||
07d777fe SR |
3188 | void trace_printk_init_buffers(void) |
3189 | { | |
07d777fe SR |
3190 | if (buffers_allocated) |
3191 | return; | |
3192 | ||
3193 | if (alloc_percpu_trace_buffer()) | |
3194 | return; | |
3195 | ||
2184db46 SR |
3196 | /* trace_printk() is for debug use only. Don't use it in production. */ |
3197 | ||
a395d6a7 JP |
3198 | pr_warn("\n"); |
3199 | pr_warn("**********************************************************\n"); | |
3200 | pr_warn("** NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE **\n"); | |
3201 | pr_warn("** **\n"); | |
3202 | pr_warn("** trace_printk() being used. Allocating extra memory. **\n"); | |
3203 | pr_warn("** **\n"); | |
3204 | pr_warn("** This means that this is a DEBUG kernel and it is **\n"); | |
3205 | pr_warn("** unsafe for production use. **\n"); | |
3206 | pr_warn("** **\n"); | |
3207 | pr_warn("** If you see this message and you are not debugging **\n"); | |
3208 | pr_warn("** the kernel, report this immediately to your vendor! **\n"); | |
3209 | pr_warn("** **\n"); | |
3210 | pr_warn("** NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE **\n"); | |
3211 | pr_warn("**********************************************************\n"); | |
07d777fe | 3212 | |
b382ede6 SR |
3213 | /* Expand the buffers to set size */ |
3214 | tracing_update_buffers(); | |
3215 | ||
07d777fe | 3216 | buffers_allocated = 1; |
81698831 SR |
3217 | |
3218 | /* | |
3219 | * trace_printk_init_buffers() can be called by modules. | |
3220 | * If that happens, then we need to start cmdline recording | |
3221 | * directly here. If the global_trace.buffer is already | |
3222 | * allocated here, then this was called by module code. | |
3223 | */ | |
1c5eb448 | 3224 | if (global_trace.array_buffer.buffer) |
81698831 SR |
3225 | tracing_start_cmdline_record(); |
3226 | } | |
f45d1225 | 3227 | EXPORT_SYMBOL_GPL(trace_printk_init_buffers); |
81698831 SR |
3228 | |
3229 | void trace_printk_start_comm(void) | |
3230 | { | |
3231 | /* Start tracing comms if trace printk is set */ | |
3232 | if (!buffers_allocated) | |
3233 | return; | |
3234 | tracing_start_cmdline_record(); | |
3235 | } | |
3236 | ||
3237 | static void trace_printk_start_stop_comm(int enabled) | |
3238 | { | |
3239 | if (!buffers_allocated) | |
3240 | return; | |
3241 | ||
3242 | if (enabled) | |
3243 | tracing_start_cmdline_record(); | |
3244 | else | |
3245 | tracing_stop_cmdline_record(); | |
07d777fe SR |
3246 | } |
3247 | ||
769b0441 | 3248 | /** |
48ead020 | 3249 | * trace_vbprintk - write binary msg to tracing buffer |
c68c9ec1 JK |
3250 | * @ip: The address of the caller |
3251 | * @fmt: The string format to write to the buffer | |
3252 | * @args: Arguments for @fmt | |
769b0441 | 3253 | */ |
40ce74f1 | 3254 | int trace_vbprintk(unsigned long ip, const char *fmt, va_list args) |
769b0441 | 3255 | { |
2425bcb9 | 3256 | struct trace_event_call *call = &event_bprint; |
769b0441 | 3257 | struct ring_buffer_event *event; |
13292494 | 3258 | struct trace_buffer *buffer; |
769b0441 | 3259 | struct trace_array *tr = &global_trace; |
48ead020 | 3260 | struct bprint_entry *entry; |
36590c50 | 3261 | unsigned int trace_ctx; |
07d777fe | 3262 | char *tbuffer; |
36590c50 | 3263 | int len = 0, size; |
769b0441 FW |
3264 | |
3265 | if (unlikely(tracing_selftest_running || tracing_disabled)) | |
3266 | return 0; | |
3267 | ||
3268 | /* Don't pollute graph traces with trace_vprintk internals */ | |
3269 | pause_graph_tracing(); | |
3270 | ||
36590c50 | 3271 | trace_ctx = tracing_gen_ctx(); |
5168ae50 | 3272 | preempt_disable_notrace(); |
769b0441 | 3273 | |
07d777fe SR |
3274 | tbuffer = get_trace_buf(); |
3275 | if (!tbuffer) { | |
3276 | len = 0; | |
e2ace001 | 3277 | goto out_nobuffer; |
07d777fe | 3278 | } |
769b0441 | 3279 | |
07d777fe | 3280 | len = vbin_printf((u32 *)tbuffer, TRACE_BUF_SIZE/sizeof(int), fmt, args); |
769b0441 | 3281 | |
07d777fe | 3282 | if (len > TRACE_BUF_SIZE/sizeof(int) || len < 0) |
34423f25 | 3283 | goto out_put; |
769b0441 FW |
3284 | |
3285 | size = sizeof(*entry) + sizeof(u32) * len; | |
1c5eb448 | 3286 | buffer = tr->array_buffer.buffer; |
82d1b815 | 3287 | ring_buffer_nest_start(buffer); |
3e9a8aad | 3288 | event = __trace_buffer_lock_reserve(buffer, TRACE_BPRINT, size, |
36590c50 | 3289 | trace_ctx); |
769b0441 | 3290 | if (!event) |
07d777fe | 3291 | goto out; |
769b0441 FW |
3292 | entry = ring_buffer_event_data(event); |
3293 | entry->ip = ip; | |
769b0441 FW |
3294 | entry->fmt = fmt; |
3295 | ||
07d777fe | 3296 | memcpy(entry->buf, tbuffer, sizeof(u32) * len); |
f306cc82 | 3297 | if (!call_filter_check_discard(call, entry, buffer, event)) { |
7ffbd48d | 3298 | __buffer_unlock_commit(buffer, event); |
36590c50 | 3299 | ftrace_trace_stack(tr, buffer, trace_ctx, 6, NULL); |
d931369b | 3300 | } |
769b0441 | 3301 | |
769b0441 | 3302 | out: |
82d1b815 | 3303 | ring_buffer_nest_end(buffer); |
34423f25 | 3304 | out_put: |
e2ace001 AL |
3305 | put_trace_buf(); |
3306 | ||
3307 | out_nobuffer: | |
5168ae50 | 3308 | preempt_enable_notrace(); |
769b0441 FW |
3309 | unpause_graph_tracing(); |
3310 | ||
3311 | return len; | |
3312 | } | |
48ead020 FW |
3313 | EXPORT_SYMBOL_GPL(trace_vbprintk); |
3314 | ||
26b68dd2 | 3315 | __printf(3, 0) |
12883efb | 3316 | static int |
13292494 | 3317 | __trace_array_vprintk(struct trace_buffer *buffer, |
12883efb | 3318 | unsigned long ip, const char *fmt, va_list args) |
48ead020 | 3319 | { |
2425bcb9 | 3320 | struct trace_event_call *call = &event_print; |
48ead020 | 3321 | struct ring_buffer_event *event; |
36590c50 | 3322 | int len = 0, size; |
48ead020 | 3323 | struct print_entry *entry; |
36590c50 | 3324 | unsigned int trace_ctx; |
07d777fe | 3325 | char *tbuffer; |
48ead020 FW |
3326 | |
3327 | if (tracing_disabled || tracing_selftest_running) | |
3328 | return 0; | |
3329 | ||
07d777fe SR |
3330 | /* Don't pollute graph traces with trace_vprintk internals */ |
3331 | pause_graph_tracing(); | |
3332 | ||
36590c50 | 3333 | trace_ctx = tracing_gen_ctx(); |
48ead020 | 3334 | preempt_disable_notrace(); |
48ead020 | 3335 | |
07d777fe SR |
3336 | |
3337 | tbuffer = get_trace_buf(); | |
3338 | if (!tbuffer) { | |
3339 | len = 0; | |
e2ace001 | 3340 | goto out_nobuffer; |
07d777fe | 3341 | } |
48ead020 | 3342 | |
3558a5ac | 3343 | len = vscnprintf(tbuffer, TRACE_BUF_SIZE, fmt, args); |
48ead020 FW |
3344 | |
3345 | size = sizeof(*entry) + len + 1; | |
82d1b815 | 3346 | ring_buffer_nest_start(buffer); |
3e9a8aad | 3347 | event = __trace_buffer_lock_reserve(buffer, TRACE_PRINT, size, |
36590c50 | 3348 | trace_ctx); |
48ead020 | 3349 | if (!event) |
07d777fe | 3350 | goto out; |
48ead020 | 3351 | entry = ring_buffer_event_data(event); |
c13d2f7c | 3352 | entry->ip = ip; |
48ead020 | 3353 | |
3558a5ac | 3354 | memcpy(&entry->buf, tbuffer, len + 1); |
f306cc82 | 3355 | if (!call_filter_check_discard(call, entry, buffer, event)) { |
7ffbd48d | 3356 | __buffer_unlock_commit(buffer, event); |
36590c50 | 3357 | ftrace_trace_stack(&global_trace, buffer, trace_ctx, 6, NULL); |
d931369b | 3358 | } |
e2ace001 AL |
3359 | |
3360 | out: | |
82d1b815 | 3361 | ring_buffer_nest_end(buffer); |
e2ace001 AL |
3362 | put_trace_buf(); |
3363 | ||
3364 | out_nobuffer: | |
48ead020 | 3365 | preempt_enable_notrace(); |
07d777fe | 3366 | unpause_graph_tracing(); |
48ead020 FW |
3367 | |
3368 | return len; | |
3369 | } | |
659372d3 | 3370 | |
26b68dd2 | 3371 | __printf(3, 0) |
12883efb SRRH |
3372 | int trace_array_vprintk(struct trace_array *tr, |
3373 | unsigned long ip, const char *fmt, va_list args) | |
3374 | { | |
1c5eb448 | 3375 | return __trace_array_vprintk(tr->array_buffer.buffer, ip, fmt, args); |
12883efb SRRH |
3376 | } |
3377 | ||
38ce2a9e SRV |
3378 | /** |
3379 | * trace_array_printk - Print a message to a specific instance | |
3380 | * @tr: The instance trace_array descriptor | |
3381 | * @ip: The instruction pointer that this is called from. | |
3382 | * @fmt: The format to print (printf format) | |
3383 | * | |
3384 | * If a subsystem sets up its own instance, they have the right to | |
3385 | * printk strings into their tracing instance buffer using this | |
3386 | * function. Note, this function will not write into the top level | |
3387 | * buffer (use trace_printk() for that), as writing into the top level | |
3388 | * buffer should only have events that can be individually disabled. | |
3389 | * trace_printk() is only used for debugging a kernel, and should not | |
f2cc020d | 3390 | * be ever incorporated in normal use. |
38ce2a9e SRV |
3391 | * |
3392 | * trace_array_printk() can be used, as it will not add noise to the | |
3393 | * top level tracing buffer. | |
3394 | * | |
3395 | * Note, trace_array_init_printk() must be called on @tr before this | |
3396 | * can be used. | |
3397 | */ | |
26b68dd2 | 3398 | __printf(3, 0) |
12883efb SRRH |
3399 | int trace_array_printk(struct trace_array *tr, |
3400 | unsigned long ip, const char *fmt, ...) | |
3401 | { | |
3402 | int ret; | |
3403 | va_list ap; | |
3404 | ||
953ae45a DI |
3405 | if (!tr) |
3406 | return -ENOENT; | |
3407 | ||
c791cc4b SRV |
3408 | /* This is only allowed for created instances */ |
3409 | if (tr == &global_trace) | |
3410 | return 0; | |
3411 | ||
3412 | if (!(tr->trace_flags & TRACE_ITER_PRINTK)) | |
3413 | return 0; | |
3414 | ||
12883efb SRRH |
3415 | va_start(ap, fmt); |
3416 | ret = trace_array_vprintk(tr, ip, fmt, ap); | |
3417 | va_end(ap); | |
3418 | return ret; | |
3419 | } | |
f45d1225 | 3420 | EXPORT_SYMBOL_GPL(trace_array_printk); |
12883efb | 3421 | |
38ce2a9e SRV |
3422 | /** |
3423 | * trace_array_init_printk - Initialize buffers for trace_array_printk() | |
3424 | * @tr: The trace array to initialize the buffers for | |
3425 | * | |
3426 | * As trace_array_printk() only writes into instances, they are OK to | |
3427 | * have in the kernel (unlike trace_printk()). This needs to be called | |
3428 | * before trace_array_printk() can be used on a trace_array. | |
3429 | */ | |
3430 | int trace_array_init_printk(struct trace_array *tr) | |
3431 | { | |
3432 | if (!tr) | |
3433 | return -ENOENT; | |
3434 | ||
3435 | /* This is only allowed for created instances */ | |
3436 | if (tr == &global_trace) | |
3437 | return -EINVAL; | |
3438 | ||
3439 | return alloc_percpu_trace_buffer(); | |
3440 | } | |
3441 | EXPORT_SYMBOL_GPL(trace_array_init_printk); | |
3442 | ||
26b68dd2 | 3443 | __printf(3, 4) |
13292494 | 3444 | int trace_array_printk_buf(struct trace_buffer *buffer, |
12883efb SRRH |
3445 | unsigned long ip, const char *fmt, ...) |
3446 | { | |
3447 | int ret; | |
3448 | va_list ap; | |
3449 | ||
983f938a | 3450 | if (!(global_trace.trace_flags & TRACE_ITER_PRINTK)) |
12883efb SRRH |
3451 | return 0; |
3452 | ||
3453 | va_start(ap, fmt); | |
3454 | ret = __trace_array_vprintk(buffer, ip, fmt, ap); | |
3455 | va_end(ap); | |
3456 | return ret; | |
3457 | } | |
3458 | ||
26b68dd2 | 3459 | __printf(2, 0) |
659372d3 SR |
3460 | int trace_vprintk(unsigned long ip, const char *fmt, va_list args) |
3461 | { | |
a813a159 | 3462 | return trace_array_vprintk(&global_trace, ip, fmt, args); |
659372d3 | 3463 | } |
769b0441 FW |
3464 | EXPORT_SYMBOL_GPL(trace_vprintk); |
3465 | ||
e2ac8ef5 | 3466 | static void trace_iterator_increment(struct trace_iterator *iter) |
5a90f577 | 3467 | { |
6d158a81 SR |
3468 | struct ring_buffer_iter *buf_iter = trace_buffer_iter(iter, iter->cpu); |
3469 | ||
5a90f577 | 3470 | iter->idx++; |
6d158a81 | 3471 | if (buf_iter) |
bc1a72af | 3472 | ring_buffer_iter_advance(buf_iter); |
5a90f577 SR |
3473 | } |
3474 | ||
e309b41d | 3475 | static struct trace_entry * |
bc21b478 SR |
3476 | peek_next_entry(struct trace_iterator *iter, int cpu, u64 *ts, |
3477 | unsigned long *lost_events) | |
dd0e545f | 3478 | { |
3928a8a2 | 3479 | struct ring_buffer_event *event; |
6d158a81 | 3480 | struct ring_buffer_iter *buf_iter = trace_buffer_iter(iter, cpu); |
dd0e545f | 3481 | |
c9b7a4a7 | 3482 | if (buf_iter) { |
d769041f | 3483 | event = ring_buffer_iter_peek(buf_iter, ts); |
c9b7a4a7 SRV |
3484 | if (lost_events) |
3485 | *lost_events = ring_buffer_iter_dropped(buf_iter) ? | |
3486 | (unsigned long)-1 : 0; | |
3487 | } else { | |
1c5eb448 | 3488 | event = ring_buffer_peek(iter->array_buffer->buffer, cpu, ts, |
bc21b478 | 3489 | lost_events); |
c9b7a4a7 | 3490 | } |
d769041f | 3491 | |
4a9bd3f1 SR |
3492 | if (event) { |
3493 | iter->ent_size = ring_buffer_event_length(event); | |
3494 | return ring_buffer_event_data(event); | |
3495 | } | |
3496 | iter->ent_size = 0; | |
3497 | return NULL; | |
dd0e545f | 3498 | } |
d769041f | 3499 | |
dd0e545f | 3500 | static struct trace_entry * |
bc21b478 SR |
3501 | __find_next_entry(struct trace_iterator *iter, int *ent_cpu, |
3502 | unsigned long *missing_events, u64 *ent_ts) | |
bc0c38d1 | 3503 | { |
13292494 | 3504 | struct trace_buffer *buffer = iter->array_buffer->buffer; |
bc0c38d1 | 3505 | struct trace_entry *ent, *next = NULL; |
aa27497c | 3506 | unsigned long lost_events = 0, next_lost = 0; |
b04cc6b1 | 3507 | int cpu_file = iter->cpu_file; |
3928a8a2 | 3508 | u64 next_ts = 0, ts; |
bc0c38d1 | 3509 | int next_cpu = -1; |
12b5da34 | 3510 | int next_size = 0; |
bc0c38d1 SR |
3511 | int cpu; |
3512 | ||
b04cc6b1 FW |
3513 | /* |
3514 | * If we are in a per_cpu trace file, don't bother by iterating over | |
3515 | * all cpu and peek directly. | |
3516 | */ | |
ae3b5093 | 3517 | if (cpu_file > RING_BUFFER_ALL_CPUS) { |
b04cc6b1 FW |
3518 | if (ring_buffer_empty_cpu(buffer, cpu_file)) |
3519 | return NULL; | |
bc21b478 | 3520 | ent = peek_next_entry(iter, cpu_file, ent_ts, missing_events); |
b04cc6b1 FW |
3521 | if (ent_cpu) |
3522 | *ent_cpu = cpu_file; | |
3523 | ||
3524 | return ent; | |
3525 | } | |
3526 | ||
ab46428c | 3527 | for_each_tracing_cpu(cpu) { |
dd0e545f | 3528 | |
3928a8a2 SR |
3529 | if (ring_buffer_empty_cpu(buffer, cpu)) |
3530 | continue; | |
dd0e545f | 3531 | |
bc21b478 | 3532 | ent = peek_next_entry(iter, cpu, &ts, &lost_events); |
dd0e545f | 3533 | |
cdd31cd2 IM |
3534 | /* |
3535 | * Pick the entry with the smallest timestamp: | |
3536 | */ | |
3928a8a2 | 3537 | if (ent && (!next || ts < next_ts)) { |
bc0c38d1 SR |
3538 | next = ent; |
3539 | next_cpu = cpu; | |
3928a8a2 | 3540 | next_ts = ts; |
bc21b478 | 3541 | next_lost = lost_events; |
12b5da34 | 3542 | next_size = iter->ent_size; |
bc0c38d1 SR |
3543 | } |
3544 | } | |
3545 | ||
12b5da34 SR |
3546 | iter->ent_size = next_size; |
3547 | ||
bc0c38d1 SR |
3548 | if (ent_cpu) |
3549 | *ent_cpu = next_cpu; | |
3550 | ||
3928a8a2 SR |
3551 | if (ent_ts) |
3552 | *ent_ts = next_ts; | |
3553 | ||
bc21b478 SR |
3554 | if (missing_events) |
3555 | *missing_events = next_lost; | |
3556 | ||
bc0c38d1 SR |
3557 | return next; |
3558 | } | |
3559 | ||
efbbdaa2 MH |
3560 | #define STATIC_FMT_BUF_SIZE 128 |
3561 | static char static_fmt_buf[STATIC_FMT_BUF_SIZE]; | |
3562 | ||
3563 | static char *trace_iter_expand_format(struct trace_iterator *iter) | |
3564 | { | |
3565 | char *tmp; | |
3566 | ||
0e1e71d3 SRV |
3567 | /* |
3568 | * iter->tr is NULL when used with tp_printk, which makes | |
3569 | * this get called where it is not safe to call krealloc(). | |
3570 | */ | |
3571 | if (!iter->tr || iter->fmt == static_fmt_buf) | |
efbbdaa2 MH |
3572 | return NULL; |
3573 | ||
3574 | tmp = krealloc(iter->fmt, iter->fmt_size + STATIC_FMT_BUF_SIZE, | |
3575 | GFP_KERNEL); | |
3576 | if (tmp) { | |
3577 | iter->fmt_size += STATIC_FMT_BUF_SIZE; | |
3578 | iter->fmt = tmp; | |
3579 | } | |
3580 | ||
3581 | return tmp; | |
3582 | } | |
3583 | ||
9a6944fe SRV |
3584 | /* Returns true if the string is safe to dereference from an event */ |
3585 | static bool trace_safe_str(struct trace_iterator *iter, const char *str) | |
3586 | { | |
3587 | unsigned long addr = (unsigned long)str; | |
3588 | struct trace_event *trace_event; | |
3589 | struct trace_event_call *event; | |
3590 | ||
3591 | /* OK if part of the event data */ | |
3592 | if ((addr >= (unsigned long)iter->ent) && | |
3593 | (addr < (unsigned long)iter->ent + iter->ent_size)) | |
3594 | return true; | |
3595 | ||
3596 | /* OK if part of the temp seq buffer */ | |
3597 | if ((addr >= (unsigned long)iter->tmp_seq.buffer) && | |
3598 | (addr < (unsigned long)iter->tmp_seq.buffer + PAGE_SIZE)) | |
3599 | return true; | |
3600 | ||
3601 | /* Core rodata can not be freed */ | |
3602 | if (is_kernel_rodata(addr)) | |
3603 | return true; | |
3604 | ||
3605 | if (trace_is_tracepoint_string(str)) | |
3606 | return true; | |
3607 | ||
3608 | /* | |
3609 | * Now this could be a module event, referencing core module | |
3610 | * data, which is OK. | |
3611 | */ | |
3612 | if (!iter->ent) | |
3613 | return false; | |
3614 | ||
3615 | trace_event = ftrace_find_event(iter->ent->type); | |
3616 | if (!trace_event) | |
3617 | return false; | |
3618 | ||
3619 | event = container_of(trace_event, struct trace_event_call, event); | |
3620 | if (!event->mod) | |
3621 | return false; | |
3622 | ||
3623 | /* Would rather have rodata, but this will suffice */ | |
3624 | if (within_module_core(addr, event->mod)) | |
3625 | return true; | |
3626 | ||
3627 | return false; | |
3628 | } | |
3629 | ||
3630 | static const char *show_buffer(struct trace_seq *s) | |
3631 | { | |
3632 | struct seq_buf *seq = &s->seq; | |
3633 | ||
3634 | seq_buf_terminate(seq); | |
3635 | ||
3636 | return seq->buffer; | |
3637 | } | |
3638 | ||
3639 | static DEFINE_STATIC_KEY_FALSE(trace_no_verify); | |
3640 | ||
3641 | static int test_can_verify_check(const char *fmt, ...) | |
3642 | { | |
3643 | char buf[16]; | |
3644 | va_list ap; | |
3645 | int ret; | |
3646 | ||
3647 | /* | |
3648 | * The verifier is dependent on vsnprintf() modifies the va_list | |
3649 | * passed to it, where it is sent as a reference. Some architectures | |
3650 | * (like x86_32) passes it by value, which means that vsnprintf() | |
3651 | * does not modify the va_list passed to it, and the verifier | |
3652 | * would then need to be able to understand all the values that | |
3653 | * vsnprintf can use. If it is passed by value, then the verifier | |
3654 | * is disabled. | |
3655 | */ | |
3656 | va_start(ap, fmt); | |
3657 | vsnprintf(buf, 16, "%d", ap); | |
3658 | ret = va_arg(ap, int); | |
3659 | va_end(ap); | |
3660 | ||
3661 | return ret; | |
3662 | } | |
3663 | ||
3664 | static void test_can_verify(void) | |
3665 | { | |
3666 | if (!test_can_verify_check("%d %d", 0, 1)) { | |
3667 | pr_info("trace event string verifier disabled\n"); | |
3668 | static_branch_inc(&trace_no_verify); | |
3669 | } | |
3670 | } | |
3671 | ||
3672 | /** | |
3673 | * trace_check_vprintf - Check dereferenced strings while writing to the seq buffer | |
3674 | * @iter: The iterator that holds the seq buffer and the event being printed | |
3675 | * @fmt: The format used to print the event | |
3676 | * @ap: The va_list holding the data to print from @fmt. | |
3677 | * | |
3678 | * This writes the data into the @iter->seq buffer using the data from | |
3679 | * @fmt and @ap. If the format has a %s, then the source of the string | |
3680 | * is examined to make sure it is safe to print, otherwise it will | |
3681 | * warn and print "[UNSAFE MEMORY]" in place of the dereferenced string | |
3682 | * pointer. | |
3683 | */ | |
3684 | void trace_check_vprintf(struct trace_iterator *iter, const char *fmt, | |
3685 | va_list ap) | |
3686 | { | |
3687 | const char *p = fmt; | |
3688 | const char *str; | |
3689 | int i, j; | |
3690 | ||
3691 | if (WARN_ON_ONCE(!fmt)) | |
3692 | return; | |
3693 | ||
3694 | if (static_branch_unlikely(&trace_no_verify)) | |
3695 | goto print; | |
3696 | ||
3697 | /* Don't bother checking when doing a ftrace_dump() */ | |
3698 | if (iter->fmt == static_fmt_buf) | |
3699 | goto print; | |
3700 | ||
3701 | while (*p) { | |
eb01f535 SRV |
3702 | bool star = false; |
3703 | int len = 0; | |
3704 | ||
9a6944fe SRV |
3705 | j = 0; |
3706 | ||
3707 | /* We only care about %s and variants */ | |
3708 | for (i = 0; p[i]; i++) { | |
3709 | if (i + 1 >= iter->fmt_size) { | |
3710 | /* | |
3711 | * If we can't expand the copy buffer, | |
3712 | * just print it. | |
3713 | */ | |
3714 | if (!trace_iter_expand_format(iter)) | |
3715 | goto print; | |
3716 | } | |
3717 | ||
3718 | if (p[i] == '\\' && p[i+1]) { | |
3719 | i++; | |
3720 | continue; | |
3721 | } | |
3722 | if (p[i] == '%') { | |
3723 | /* Need to test cases like %08.*s */ | |
3724 | for (j = 1; p[i+j]; j++) { | |
3725 | if (isdigit(p[i+j]) || | |
9a6944fe SRV |
3726 | p[i+j] == '.') |
3727 | continue; | |
eb01f535 SRV |
3728 | if (p[i+j] == '*') { |
3729 | star = true; | |
3730 | continue; | |
3731 | } | |
9a6944fe SRV |
3732 | break; |
3733 | } | |
3734 | if (p[i+j] == 's') | |
3735 | break; | |
eb01f535 | 3736 | star = false; |
9a6944fe SRV |
3737 | } |
3738 | j = 0; | |
3739 | } | |
3740 | /* If no %s found then just print normally */ | |
3741 | if (!p[i]) | |
3742 | break; | |
3743 | ||
3744 | /* Copy up to the %s, and print that */ | |
3745 | strncpy(iter->fmt, p, i); | |
3746 | iter->fmt[i] = '\0'; | |
3747 | trace_seq_vprintf(&iter->seq, iter->fmt, ap); | |
3748 | ||
eb01f535 SRV |
3749 | if (star) |
3750 | len = va_arg(ap, int); | |
3751 | ||
9a6944fe SRV |
3752 | /* The ap now points to the string data of the %s */ |
3753 | str = va_arg(ap, const char *); | |
3754 | ||
3755 | /* | |
3756 | * If you hit this warning, it is likely that the | |
3757 | * trace event in question used %s on a string that | |
3758 | * was saved at the time of the event, but may not be | |
3759 | * around when the trace is read. Use __string(), | |
3760 | * __assign_str() and __get_str() helpers in the TRACE_EVENT() | |
3761 | * instead. See samples/trace_events/trace-events-sample.h | |
3762 | * for reference. | |
3763 | */ | |
3764 | if (WARN_ONCE(!trace_safe_str(iter, str), | |
3765 | "fmt: '%s' current_buffer: '%s'", | |
3766 | fmt, show_buffer(&iter->seq))) { | |
3767 | int ret; | |
3768 | ||
3769 | /* Try to safely read the string */ | |
eb01f535 SRV |
3770 | if (star) { |
3771 | if (len + 1 > iter->fmt_size) | |
3772 | len = iter->fmt_size - 1; | |
3773 | if (len < 0) | |
3774 | len = 0; | |
3775 | ret = copy_from_kernel_nofault(iter->fmt, str, len); | |
3776 | iter->fmt[len] = 0; | |
3777 | star = false; | |
3778 | } else { | |
3779 | ret = strncpy_from_kernel_nofault(iter->fmt, str, | |
3780 | iter->fmt_size); | |
3781 | } | |
9a6944fe SRV |
3782 | if (ret < 0) |
3783 | trace_seq_printf(&iter->seq, "(0x%px)", str); | |
3784 | else | |
3785 | trace_seq_printf(&iter->seq, "(0x%px:%s)", | |
3786 | str, iter->fmt); | |
3787 | str = "[UNSAFE-MEMORY]"; | |
3788 | strcpy(iter->fmt, "%s"); | |
3789 | } else { | |
3790 | strncpy(iter->fmt, p + i, j + 1); | |
3791 | iter->fmt[j+1] = '\0'; | |
3792 | } | |
eb01f535 SRV |
3793 | if (star) |
3794 | trace_seq_printf(&iter->seq, iter->fmt, len, str); | |
3795 | else | |
3796 | trace_seq_printf(&iter->seq, iter->fmt, str); | |
9a6944fe SRV |
3797 | |
3798 | p += i + j + 1; | |
3799 | } | |
3800 | print: | |
3801 | if (*p) | |
3802 | trace_seq_vprintf(&iter->seq, p, ap); | |
3803 | } | |
3804 | ||
efbbdaa2 MH |
3805 | const char *trace_event_format(struct trace_iterator *iter, const char *fmt) |
3806 | { | |
3807 | const char *p, *new_fmt; | |
3808 | char *q; | |
3809 | ||
3810 | if (WARN_ON_ONCE(!fmt)) | |
3811 | return fmt; | |
3812 | ||
0e1e71d3 | 3813 | if (!iter->tr || iter->tr->trace_flags & TRACE_ITER_HASH_PTR) |
a345a671 MH |
3814 | return fmt; |
3815 | ||
efbbdaa2 MH |
3816 | p = fmt; |
3817 | new_fmt = q = iter->fmt; | |
3818 | while (*p) { | |
3819 | if (unlikely(q - new_fmt + 3 > iter->fmt_size)) { | |
3820 | if (!trace_iter_expand_format(iter)) | |
3821 | return fmt; | |
3822 | ||
3823 | q += iter->fmt - new_fmt; | |
3824 | new_fmt = iter->fmt; | |
3825 | } | |
3826 | ||
3827 | *q++ = *p++; | |
3828 | ||
3829 | /* Replace %p with %px */ | |
3830 | if (p[-1] == '%') { | |
3831 | if (p[0] == '%') { | |
3832 | *q++ = *p++; | |
3833 | } else if (p[0] == 'p' && !isalnum(p[1])) { | |
3834 | *q++ = *p++; | |
3835 | *q++ = 'x'; | |
3836 | } | |
3837 | } | |
3838 | } | |
3839 | *q = '\0'; | |
3840 | ||
3841 | return new_fmt; | |
3842 | } | |
3843 | ||
8e99cf91 | 3844 | #define STATIC_TEMP_BUF_SIZE 128 |
8fa655a3 | 3845 | static char static_temp_buf[STATIC_TEMP_BUF_SIZE] __aligned(4); |
8e99cf91 | 3846 | |
dd0e545f | 3847 | /* Find the next real entry, without updating the iterator itself */ |
c4a8e8be FW |
3848 | struct trace_entry *trace_find_next_entry(struct trace_iterator *iter, |
3849 | int *ent_cpu, u64 *ent_ts) | |
bc0c38d1 | 3850 | { |
ff895103 SRV |
3851 | /* __find_next_entry will reset ent_size */ |
3852 | int ent_size = iter->ent_size; | |
3853 | struct trace_entry *entry; | |
3854 | ||
8e99cf91 SRV |
3855 | /* |
3856 | * If called from ftrace_dump(), then the iter->temp buffer | |
3857 | * will be the static_temp_buf and not created from kmalloc. | |
3858 | * If the entry size is greater than the buffer, we can | |
3859 | * not save it. Just return NULL in that case. This is only | |
3860 | * used to add markers when two consecutive events' time | |
3861 | * stamps have a large delta. See trace_print_lat_context() | |
3862 | */ | |
3863 | if (iter->temp == static_temp_buf && | |
3864 | STATIC_TEMP_BUF_SIZE < ent_size) | |
3865 | return NULL; | |
3866 | ||
ff895103 SRV |
3867 | /* |
3868 | * The __find_next_entry() may call peek_next_entry(), which may | |
3869 | * call ring_buffer_peek() that may make the contents of iter->ent | |
3870 | * undefined. Need to copy iter->ent now. | |
3871 | */ | |
3872 | if (iter->ent && iter->ent != iter->temp) { | |
8e99cf91 SRV |
3873 | if ((!iter->temp || iter->temp_size < iter->ent_size) && |
3874 | !WARN_ON_ONCE(iter->temp == static_temp_buf)) { | |
851e6f61 SRV |
3875 | void *temp; |
3876 | temp = kmalloc(iter->ent_size, GFP_KERNEL); | |
3877 | if (!temp) | |
ff895103 | 3878 | return NULL; |
851e6f61 SRV |
3879 | kfree(iter->temp); |
3880 | iter->temp = temp; | |
3881 | iter->temp_size = iter->ent_size; | |
ff895103 SRV |
3882 | } |
3883 | memcpy(iter->temp, iter->ent, iter->ent_size); | |
ff895103 SRV |
3884 | iter->ent = iter->temp; |
3885 | } | |
3886 | entry = __find_next_entry(iter, ent_cpu, NULL, ent_ts); | |
3887 | /* Put back the original ent_size */ | |
3888 | iter->ent_size = ent_size; | |
3889 | ||
3890 | return entry; | |
dd0e545f SR |
3891 | } |
3892 | ||
3893 | /* Find the next real entry, and increment the iterator to the next entry */ | |
955b61e5 | 3894 | void *trace_find_next_entry_inc(struct trace_iterator *iter) |
dd0e545f | 3895 | { |
bc21b478 SR |
3896 | iter->ent = __find_next_entry(iter, &iter->cpu, |
3897 | &iter->lost_events, &iter->ts); | |
dd0e545f | 3898 | |
3928a8a2 | 3899 | if (iter->ent) |
e2ac8ef5 | 3900 | trace_iterator_increment(iter); |
dd0e545f | 3901 | |
3928a8a2 | 3902 | return iter->ent ? iter : NULL; |
b3806b43 | 3903 | } |
bc0c38d1 | 3904 | |
e309b41d | 3905 | static void trace_consume(struct trace_iterator *iter) |
b3806b43 | 3906 | { |
1c5eb448 | 3907 | ring_buffer_consume(iter->array_buffer->buffer, iter->cpu, &iter->ts, |
bc21b478 | 3908 | &iter->lost_events); |
bc0c38d1 SR |
3909 | } |
3910 | ||
e309b41d | 3911 | static void *s_next(struct seq_file *m, void *v, loff_t *pos) |
bc0c38d1 SR |
3912 | { |
3913 | struct trace_iterator *iter = m->private; | |
bc0c38d1 | 3914 | int i = (int)*pos; |
4e3c3333 | 3915 | void *ent; |
bc0c38d1 | 3916 | |
a63ce5b3 SR |
3917 | WARN_ON_ONCE(iter->leftover); |
3918 | ||
bc0c38d1 SR |
3919 | (*pos)++; |
3920 | ||
3921 | /* can't go backwards */ | |
3922 | if (iter->idx > i) | |
3923 | return NULL; | |
3924 | ||
3925 | if (iter->idx < 0) | |
955b61e5 | 3926 | ent = trace_find_next_entry_inc(iter); |
bc0c38d1 SR |
3927 | else |
3928 | ent = iter; | |
3929 | ||
3930 | while (ent && iter->idx < i) | |
955b61e5 | 3931 | ent = trace_find_next_entry_inc(iter); |
bc0c38d1 SR |
3932 | |
3933 | iter->pos = *pos; | |
3934 | ||
bc0c38d1 SR |
3935 | return ent; |
3936 | } | |
3937 | ||
955b61e5 | 3938 | void tracing_iter_reset(struct trace_iterator *iter, int cpu) |
2f26ebd5 | 3939 | { |
2f26ebd5 SR |
3940 | struct ring_buffer_iter *buf_iter; |
3941 | unsigned long entries = 0; | |
3942 | u64 ts; | |
3943 | ||
1c5eb448 | 3944 | per_cpu_ptr(iter->array_buffer->data, cpu)->skipped_entries = 0; |
2f26ebd5 | 3945 | |
6d158a81 SR |
3946 | buf_iter = trace_buffer_iter(iter, cpu); |
3947 | if (!buf_iter) | |
2f26ebd5 SR |
3948 | return; |
3949 | ||
2f26ebd5 SR |
3950 | ring_buffer_iter_reset(buf_iter); |
3951 | ||
3952 | /* | |
3953 | * We could have the case with the max latency tracers | |
3954 | * that a reset never took place on a cpu. This is evident | |
3955 | * by the timestamp being before the start of the buffer. | |
3956 | */ | |
69243720 | 3957 | while (ring_buffer_iter_peek(buf_iter, &ts)) { |
1c5eb448 | 3958 | if (ts >= iter->array_buffer->time_start) |
2f26ebd5 SR |
3959 | break; |
3960 | entries++; | |
bc1a72af | 3961 | ring_buffer_iter_advance(buf_iter); |
2f26ebd5 SR |
3962 | } |
3963 | ||
1c5eb448 | 3964 | per_cpu_ptr(iter->array_buffer->data, cpu)->skipped_entries = entries; |
2f26ebd5 SR |
3965 | } |
3966 | ||
d7350c3f | 3967 | /* |
d7350c3f FW |
3968 | * The current tracer is copied to avoid a global locking |
3969 | * all around. | |
3970 | */ | |
bc0c38d1 SR |
3971 | static void *s_start(struct seq_file *m, loff_t *pos) |
3972 | { | |
3973 | struct trace_iterator *iter = m->private; | |
2b6080f2 | 3974 | struct trace_array *tr = iter->tr; |
b04cc6b1 | 3975 | int cpu_file = iter->cpu_file; |
bc0c38d1 SR |
3976 | void *p = NULL; |
3977 | loff_t l = 0; | |
3928a8a2 | 3978 | int cpu; |
bc0c38d1 | 3979 | |
2fd196ec HT |
3980 | /* |
3981 | * copy the tracer to avoid using a global lock all around. | |
3982 | * iter->trace is a copy of current_trace, the pointer to the | |
3983 | * name may be used instead of a strcmp(), as iter->trace->name | |
3984 | * will point to the same string as current_trace->name. | |
3985 | */ | |
bc0c38d1 | 3986 | mutex_lock(&trace_types_lock); |
2b6080f2 SR |
3987 | if (unlikely(tr->current_trace && iter->trace->name != tr->current_trace->name)) |
3988 | *iter->trace = *tr->current_trace; | |
d7350c3f | 3989 | mutex_unlock(&trace_types_lock); |
bc0c38d1 | 3990 | |
12883efb | 3991 | #ifdef CONFIG_TRACER_MAX_TRACE |
debdd57f HT |
3992 | if (iter->snapshot && iter->trace->use_max_tr) |
3993 | return ERR_PTR(-EBUSY); | |
12883efb | 3994 | #endif |
debdd57f | 3995 | |
bc0c38d1 SR |
3996 | if (*pos != iter->pos) { |
3997 | iter->ent = NULL; | |
3998 | iter->cpu = 0; | |
3999 | iter->idx = -1; | |
4000 | ||
ae3b5093 | 4001 | if (cpu_file == RING_BUFFER_ALL_CPUS) { |
b04cc6b1 | 4002 | for_each_tracing_cpu(cpu) |
2f26ebd5 | 4003 | tracing_iter_reset(iter, cpu); |
b04cc6b1 | 4004 | } else |
2f26ebd5 | 4005 | tracing_iter_reset(iter, cpu_file); |
bc0c38d1 | 4006 | |
ac91d854 | 4007 | iter->leftover = 0; |
bc0c38d1 SR |
4008 | for (p = iter; p && l < *pos; p = s_next(m, p, &l)) |
4009 | ; | |
4010 | ||
4011 | } else { | |
a63ce5b3 SR |
4012 | /* |
4013 | * If we overflowed the seq_file before, then we want | |
4014 | * to just reuse the trace_seq buffer again. | |
4015 | */ | |
4016 | if (iter->leftover) | |
4017 | p = iter; | |
4018 | else { | |
4019 | l = *pos - 1; | |
4020 | p = s_next(m, p, &l); | |
4021 | } | |
bc0c38d1 SR |
4022 | } |
4023 | ||
4f535968 | 4024 | trace_event_read_lock(); |
7e53bd42 | 4025 | trace_access_lock(cpu_file); |
bc0c38d1 SR |
4026 | return p; |
4027 | } | |
4028 | ||
4029 | static void s_stop(struct seq_file *m, void *p) | |
4030 | { | |
7e53bd42 LJ |
4031 | struct trace_iterator *iter = m->private; |
4032 | ||
12883efb | 4033 | #ifdef CONFIG_TRACER_MAX_TRACE |
debdd57f HT |
4034 | if (iter->snapshot && iter->trace->use_max_tr) |
4035 | return; | |
12883efb | 4036 | #endif |
debdd57f | 4037 | |
7e53bd42 | 4038 | trace_access_unlock(iter->cpu_file); |
4f535968 | 4039 | trace_event_read_unlock(); |
bc0c38d1 SR |
4040 | } |
4041 | ||
ecffc8a8 | 4042 | static void |
1c5eb448 | 4043 | get_total_entries_cpu(struct array_buffer *buf, unsigned long *total, |
ecffc8a8 DA |
4044 | unsigned long *entries, int cpu) |
4045 | { | |
4046 | unsigned long count; | |
4047 | ||
4048 | count = ring_buffer_entries_cpu(buf->buffer, cpu); | |
4049 | /* | |
4050 | * If this buffer has skipped entries, then we hold all | |
4051 | * entries for the trace and we need to ignore the | |
4052 | * ones before the time stamp. | |
4053 | */ | |
4054 | if (per_cpu_ptr(buf->data, cpu)->skipped_entries) { | |
4055 | count -= per_cpu_ptr(buf->data, cpu)->skipped_entries; | |
4056 | /* total is the same as the entries */ | |
4057 | *total = count; | |
4058 | } else | |
4059 | *total = count + | |
4060 | ring_buffer_overrun_cpu(buf->buffer, cpu); | |
4061 | *entries = count; | |
4062 | } | |
4063 | ||
39eaf7ef | 4064 | static void |
1c5eb448 | 4065 | get_total_entries(struct array_buffer *buf, |
12883efb | 4066 | unsigned long *total, unsigned long *entries) |
39eaf7ef | 4067 | { |
ecffc8a8 | 4068 | unsigned long t, e; |
39eaf7ef SR |
4069 | int cpu; |
4070 | ||
4071 | *total = 0; | |
4072 | *entries = 0; | |
4073 | ||
4074 | for_each_tracing_cpu(cpu) { | |
ecffc8a8 DA |
4075 | get_total_entries_cpu(buf, &t, &e, cpu); |
4076 | *total += t; | |
4077 | *entries += e; | |
39eaf7ef SR |
4078 | } |
4079 | } | |
4080 | ||
ecffc8a8 DA |
4081 | unsigned long trace_total_entries_cpu(struct trace_array *tr, int cpu) |
4082 | { | |
4083 | unsigned long total, entries; | |
4084 | ||
4085 | if (!tr) | |
4086 | tr = &global_trace; | |
4087 | ||
1c5eb448 | 4088 | get_total_entries_cpu(&tr->array_buffer, &total, &entries, cpu); |
ecffc8a8 DA |
4089 | |
4090 | return entries; | |
4091 | } | |
4092 | ||
4093 | unsigned long trace_total_entries(struct trace_array *tr) | |
4094 | { | |
4095 | unsigned long total, entries; | |
4096 | ||
4097 | if (!tr) | |
4098 | tr = &global_trace; | |
4099 | ||
1c5eb448 | 4100 | get_total_entries(&tr->array_buffer, &total, &entries); |
ecffc8a8 DA |
4101 | |
4102 | return entries; | |
4103 | } | |
4104 | ||
e309b41d | 4105 | static void print_lat_help_header(struct seq_file *m) |
bc0c38d1 | 4106 | { |
795d6379 SAS |
4107 | seq_puts(m, "# _------=> CPU# \n" |
4108 | "# / _-----=> irqs-off \n" | |
4109 | "# | / _----=> need-resched \n" | |
4110 | "# || / _---=> hardirq/softirq \n" | |
4111 | "# ||| / _--=> preempt-depth \n" | |
4112 | "# |||| / delay \n" | |
4113 | "# cmd pid ||||| time | caller \n" | |
4114 | "# \\ / ||||| \\ | / \n"); | |
bc0c38d1 SR |
4115 | } |
4116 | ||
1c5eb448 | 4117 | static void print_event_info(struct array_buffer *buf, struct seq_file *m) |
bc0c38d1 | 4118 | { |
39eaf7ef SR |
4119 | unsigned long total; |
4120 | unsigned long entries; | |
4121 | ||
12883efb | 4122 | get_total_entries(buf, &total, &entries); |
39eaf7ef SR |
4123 | seq_printf(m, "# entries-in-buffer/entries-written: %lu/%lu #P:%d\n", |
4124 | entries, total, num_online_cpus()); | |
4125 | seq_puts(m, "#\n"); | |
4126 | } | |
4127 | ||
1c5eb448 | 4128 | static void print_func_help_header(struct array_buffer *buf, struct seq_file *m, |
441dae8f | 4129 | unsigned int flags) |
39eaf7ef | 4130 | { |
441dae8f JF |
4131 | bool tgid = flags & TRACE_ITER_RECORD_TGID; |
4132 | ||
12883efb | 4133 | print_event_info(buf, m); |
441dae8f | 4134 | |
795d6379 SAS |
4135 | seq_printf(m, "# TASK-PID %s CPU# TIMESTAMP FUNCTION\n", tgid ? " TGID " : ""); |
4136 | seq_printf(m, "# | | %s | | |\n", tgid ? " | " : ""); | |
bc0c38d1 SR |
4137 | } |
4138 | ||
1c5eb448 | 4139 | static void print_func_help_header_irq(struct array_buffer *buf, struct seq_file *m, |
441dae8f | 4140 | unsigned int flags) |
77271ce4 | 4141 | { |
441dae8f | 4142 | bool tgid = flags & TRACE_ITER_RECORD_TGID; |
795d6379 SAS |
4143 | const char *space = " "; |
4144 | int prec = tgid ? 12 : 2; | |
b11fb737 | 4145 | |
9e738215 QP |
4146 | print_event_info(buf, m); |
4147 | ||
795d6379 SAS |
4148 | seq_printf(m, "# %.*s _-----=> irqs-off\n", prec, space); |
4149 | seq_printf(m, "# %.*s / _----=> need-resched\n", prec, space); | |
4150 | seq_printf(m, "# %.*s| / _---=> hardirq/softirq\n", prec, space); | |
4151 | seq_printf(m, "# %.*s|| / _--=> preempt-depth\n", prec, space); | |
4152 | seq_printf(m, "# %.*s||| / delay\n", prec, space); | |
4153 | seq_printf(m, "# TASK-PID %.*s CPU# |||| TIMESTAMP FUNCTION\n", prec, " TGID "); | |
4154 | seq_printf(m, "# | | %.*s | |||| | |\n", prec, " | "); | |
77271ce4 | 4155 | } |
bc0c38d1 | 4156 | |
62b915f1 | 4157 | void |
bc0c38d1 SR |
4158 | print_trace_header(struct seq_file *m, struct trace_iterator *iter) |
4159 | { | |
983f938a | 4160 | unsigned long sym_flags = (global_trace.trace_flags & TRACE_ITER_SYM_MASK); |
1c5eb448 | 4161 | struct array_buffer *buf = iter->array_buffer; |
12883efb | 4162 | struct trace_array_cpu *data = per_cpu_ptr(buf->data, buf->cpu); |
2b6080f2 | 4163 | struct tracer *type = iter->trace; |
39eaf7ef SR |
4164 | unsigned long entries; |
4165 | unsigned long total; | |
bc0c38d1 SR |
4166 | const char *name = "preemption"; |
4167 | ||
d840f718 | 4168 | name = type->name; |
bc0c38d1 | 4169 | |
12883efb | 4170 | get_total_entries(buf, &total, &entries); |
bc0c38d1 | 4171 | |
888b55dc | 4172 | seq_printf(m, "# %s latency trace v1.1.5 on %s\n", |
bc0c38d1 | 4173 | name, UTS_RELEASE); |
888b55dc | 4174 | seq_puts(m, "# -----------------------------------" |
bc0c38d1 | 4175 | "---------------------------------\n"); |
888b55dc | 4176 | seq_printf(m, "# latency: %lu us, #%lu/%lu, CPU#%d |" |
bc0c38d1 | 4177 | " (M:%s VP:%d, KP:%d, SP:%d HP:%d", |
57f50be1 | 4178 | nsecs_to_usecs(data->saved_latency), |
bc0c38d1 | 4179 | entries, |
4c11d7ae | 4180 | total, |
12883efb | 4181 | buf->cpu, |
bc0c38d1 SR |
4182 | #if defined(CONFIG_PREEMPT_NONE) |
4183 | "server", | |
4184 | #elif defined(CONFIG_PREEMPT_VOLUNTARY) | |
4185 | "desktop", | |
b5c21b45 | 4186 | #elif defined(CONFIG_PREEMPT) |
bc0c38d1 | 4187 | "preempt", |
9c34fc4b SAS |
4188 | #elif defined(CONFIG_PREEMPT_RT) |
4189 | "preempt_rt", | |
bc0c38d1 SR |
4190 | #else |
4191 | "unknown", | |
4192 | #endif | |
4193 | /* These are reserved for later use */ | |
4194 | 0, 0, 0, 0); | |
4195 | #ifdef CONFIG_SMP | |
4196 | seq_printf(m, " #P:%d)\n", num_online_cpus()); | |
4197 | #else | |
4198 | seq_puts(m, ")\n"); | |
4199 | #endif | |
888b55dc KM |
4200 | seq_puts(m, "# -----------------\n"); |
4201 | seq_printf(m, "# | task: %.16s-%d " | |
bc0c38d1 | 4202 | "(uid:%d nice:%ld policy:%ld rt_prio:%ld)\n", |
d20b92ab EB |
4203 | data->comm, data->pid, |
4204 | from_kuid_munged(seq_user_ns(m), data->uid), data->nice, | |
bc0c38d1 | 4205 | data->policy, data->rt_priority); |
888b55dc | 4206 | seq_puts(m, "# -----------------\n"); |
bc0c38d1 SR |
4207 | |
4208 | if (data->critical_start) { | |
888b55dc | 4209 | seq_puts(m, "# => started at: "); |
214023c3 SR |
4210 | seq_print_ip_sym(&iter->seq, data->critical_start, sym_flags); |
4211 | trace_print_seq(m, &iter->seq); | |
888b55dc | 4212 | seq_puts(m, "\n# => ended at: "); |
214023c3 SR |
4213 | seq_print_ip_sym(&iter->seq, data->critical_end, sym_flags); |
4214 | trace_print_seq(m, &iter->seq); | |
8248ac05 | 4215 | seq_puts(m, "\n#\n"); |
bc0c38d1 SR |
4216 | } |
4217 | ||
888b55dc | 4218 | seq_puts(m, "#\n"); |
bc0c38d1 SR |
4219 | } |
4220 | ||
a309720c SR |
4221 | static void test_cpu_buff_start(struct trace_iterator *iter) |
4222 | { | |
4223 | struct trace_seq *s = &iter->seq; | |
983f938a | 4224 | struct trace_array *tr = iter->tr; |
a309720c | 4225 | |
983f938a | 4226 | if (!(tr->trace_flags & TRACE_ITER_ANNOTATE)) |
12ef7d44 SR |
4227 | return; |
4228 | ||
4229 | if (!(iter->iter_flags & TRACE_FILE_ANNOTATE)) | |
4230 | return; | |
4231 | ||
4dbbe2d8 MK |
4232 | if (cpumask_available(iter->started) && |
4233 | cpumask_test_cpu(iter->cpu, iter->started)) | |
a309720c SR |
4234 | return; |
4235 | ||
1c5eb448 | 4236 | if (per_cpu_ptr(iter->array_buffer->data, iter->cpu)->skipped_entries) |
2f26ebd5 SR |
4237 | return; |
4238 | ||
4dbbe2d8 | 4239 | if (cpumask_available(iter->started)) |
919cd979 | 4240 | cpumask_set_cpu(iter->cpu, iter->started); |
b0dfa978 FW |
4241 | |
4242 | /* Don't print started cpu buffer for the first entry of the trace */ | |
4243 | if (iter->idx > 1) | |
4244 | trace_seq_printf(s, "##### CPU %u buffer started ####\n", | |
4245 | iter->cpu); | |
a309720c SR |
4246 | } |
4247 | ||
2c4f035f | 4248 | static enum print_line_t print_trace_fmt(struct trace_iterator *iter) |
bc0c38d1 | 4249 | { |
983f938a | 4250 | struct trace_array *tr = iter->tr; |
214023c3 | 4251 | struct trace_seq *s = &iter->seq; |
983f938a | 4252 | unsigned long sym_flags = (tr->trace_flags & TRACE_ITER_SYM_MASK); |
4e3c3333 | 4253 | struct trace_entry *entry; |
f633cef0 | 4254 | struct trace_event *event; |
bc0c38d1 | 4255 | |
4e3c3333 | 4256 | entry = iter->ent; |
dd0e545f | 4257 | |
a309720c SR |
4258 | test_cpu_buff_start(iter); |
4259 | ||
c4a8e8be | 4260 | event = ftrace_find_event(entry->type); |
bc0c38d1 | 4261 | |
983f938a | 4262 | if (tr->trace_flags & TRACE_ITER_CONTEXT_INFO) { |
19a7fe20 SRRH |
4263 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) |
4264 | trace_print_lat_context(iter); | |
4265 | else | |
4266 | trace_print_context(iter); | |
c4a8e8be | 4267 | } |
bc0c38d1 | 4268 | |
19a7fe20 SRRH |
4269 | if (trace_seq_has_overflowed(s)) |
4270 | return TRACE_TYPE_PARTIAL_LINE; | |
4271 | ||
268ccda0 | 4272 | if (event) |
a9a57763 | 4273 | return event->funcs->trace(iter, sym_flags, event); |
d9793bd8 | 4274 | |
19a7fe20 | 4275 | trace_seq_printf(s, "Unknown type %d\n", entry->type); |
02b67518 | 4276 | |
19a7fe20 | 4277 | return trace_handle_return(s); |
bc0c38d1 SR |
4278 | } |
4279 | ||
2c4f035f | 4280 | static enum print_line_t print_raw_fmt(struct trace_iterator *iter) |
f9896bf3 | 4281 | { |
983f938a | 4282 | struct trace_array *tr = iter->tr; |
f9896bf3 IM |
4283 | struct trace_seq *s = &iter->seq; |
4284 | struct trace_entry *entry; | |
f633cef0 | 4285 | struct trace_event *event; |
f9896bf3 IM |
4286 | |
4287 | entry = iter->ent; | |
dd0e545f | 4288 | |
983f938a | 4289 | if (tr->trace_flags & TRACE_ITER_CONTEXT_INFO) |
19a7fe20 SRRH |
4290 | trace_seq_printf(s, "%d %d %llu ", |
4291 | entry->pid, iter->cpu, iter->ts); | |
4292 | ||
4293 | if (trace_seq_has_overflowed(s)) | |
4294 | return TRACE_TYPE_PARTIAL_LINE; | |
f9896bf3 | 4295 | |
f633cef0 | 4296 | event = ftrace_find_event(entry->type); |
268ccda0 | 4297 | if (event) |
a9a57763 | 4298 | return event->funcs->raw(iter, 0, event); |
d9793bd8 | 4299 | |
19a7fe20 | 4300 | trace_seq_printf(s, "%d ?\n", entry->type); |
777e208d | 4301 | |
19a7fe20 | 4302 | return trace_handle_return(s); |
f9896bf3 IM |
4303 | } |
4304 | ||
2c4f035f | 4305 | static enum print_line_t print_hex_fmt(struct trace_iterator *iter) |
5e3ca0ec | 4306 | { |
983f938a | 4307 | struct trace_array *tr = iter->tr; |
5e3ca0ec IM |
4308 | struct trace_seq *s = &iter->seq; |
4309 | unsigned char newline = '\n'; | |
4310 | struct trace_entry *entry; | |
f633cef0 | 4311 | struct trace_event *event; |
5e3ca0ec IM |
4312 | |
4313 | entry = iter->ent; | |
dd0e545f | 4314 | |
983f938a | 4315 | if (tr->trace_flags & TRACE_ITER_CONTEXT_INFO) { |
19a7fe20 SRRH |
4316 | SEQ_PUT_HEX_FIELD(s, entry->pid); |
4317 | SEQ_PUT_HEX_FIELD(s, iter->cpu); | |
4318 | SEQ_PUT_HEX_FIELD(s, iter->ts); | |
4319 | if (trace_seq_has_overflowed(s)) | |
4320 | return TRACE_TYPE_PARTIAL_LINE; | |
c4a8e8be | 4321 | } |
5e3ca0ec | 4322 | |
f633cef0 | 4323 | event = ftrace_find_event(entry->type); |
268ccda0 | 4324 | if (event) { |
a9a57763 | 4325 | enum print_line_t ret = event->funcs->hex(iter, 0, event); |
d9793bd8 ACM |
4326 | if (ret != TRACE_TYPE_HANDLED) |
4327 | return ret; | |
4328 | } | |
7104f300 | 4329 | |
19a7fe20 | 4330 | SEQ_PUT_FIELD(s, newline); |
5e3ca0ec | 4331 | |
19a7fe20 | 4332 | return trace_handle_return(s); |
5e3ca0ec IM |
4333 | } |
4334 | ||
2c4f035f | 4335 | static enum print_line_t print_bin_fmt(struct trace_iterator *iter) |
cb0f12aa | 4336 | { |
983f938a | 4337 | struct trace_array *tr = iter->tr; |
cb0f12aa IM |
4338 | struct trace_seq *s = &iter->seq; |
4339 | struct trace_entry *entry; | |
f633cef0 | 4340 | struct trace_event *event; |
cb0f12aa IM |
4341 | |
4342 | entry = iter->ent; | |
dd0e545f | 4343 | |
983f938a | 4344 | if (tr->trace_flags & TRACE_ITER_CONTEXT_INFO) { |
19a7fe20 SRRH |
4345 | SEQ_PUT_FIELD(s, entry->pid); |
4346 | SEQ_PUT_FIELD(s, iter->cpu); | |
4347 | SEQ_PUT_FIELD(s, iter->ts); | |
4348 | if (trace_seq_has_overflowed(s)) | |
4349 | return TRACE_TYPE_PARTIAL_LINE; | |
c4a8e8be | 4350 | } |
cb0f12aa | 4351 | |
f633cef0 | 4352 | event = ftrace_find_event(entry->type); |
a9a57763 SR |
4353 | return event ? event->funcs->binary(iter, 0, event) : |
4354 | TRACE_TYPE_HANDLED; | |
cb0f12aa IM |
4355 | } |
4356 | ||
62b915f1 | 4357 | int trace_empty(struct trace_iterator *iter) |
bc0c38d1 | 4358 | { |
6d158a81 | 4359 | struct ring_buffer_iter *buf_iter; |
bc0c38d1 SR |
4360 | int cpu; |
4361 | ||
9aba60fe | 4362 | /* If we are looking at one CPU buffer, only check that one */ |
ae3b5093 | 4363 | if (iter->cpu_file != RING_BUFFER_ALL_CPUS) { |
9aba60fe | 4364 | cpu = iter->cpu_file; |
6d158a81 SR |
4365 | buf_iter = trace_buffer_iter(iter, cpu); |
4366 | if (buf_iter) { | |
4367 | if (!ring_buffer_iter_empty(buf_iter)) | |
9aba60fe SR |
4368 | return 0; |
4369 | } else { | |
1c5eb448 | 4370 | if (!ring_buffer_empty_cpu(iter->array_buffer->buffer, cpu)) |
9aba60fe SR |
4371 | return 0; |
4372 | } | |
4373 | return 1; | |
4374 | } | |
4375 | ||
ab46428c | 4376 | for_each_tracing_cpu(cpu) { |
6d158a81 SR |
4377 | buf_iter = trace_buffer_iter(iter, cpu); |
4378 | if (buf_iter) { | |
4379 | if (!ring_buffer_iter_empty(buf_iter)) | |
d769041f SR |
4380 | return 0; |
4381 | } else { | |
1c5eb448 | 4382 | if (!ring_buffer_empty_cpu(iter->array_buffer->buffer, cpu)) |
d769041f SR |
4383 | return 0; |
4384 | } | |
bc0c38d1 | 4385 | } |
d769041f | 4386 | |
797d3712 | 4387 | return 1; |
bc0c38d1 SR |
4388 | } |
4389 | ||
4f535968 | 4390 | /* Called with trace_event_read_lock() held. */ |
955b61e5 | 4391 | enum print_line_t print_trace_line(struct trace_iterator *iter) |
f9896bf3 | 4392 | { |
983f938a SRRH |
4393 | struct trace_array *tr = iter->tr; |
4394 | unsigned long trace_flags = tr->trace_flags; | |
2c4f035f FW |
4395 | enum print_line_t ret; |
4396 | ||
19a7fe20 | 4397 | if (iter->lost_events) { |
c9b7a4a7 SRV |
4398 | if (iter->lost_events == (unsigned long)-1) |
4399 | trace_seq_printf(&iter->seq, "CPU:%d [LOST EVENTS]\n", | |
4400 | iter->cpu); | |
4401 | else | |
4402 | trace_seq_printf(&iter->seq, "CPU:%d [LOST %lu EVENTS]\n", | |
4403 | iter->cpu, iter->lost_events); | |
19a7fe20 SRRH |
4404 | if (trace_seq_has_overflowed(&iter->seq)) |
4405 | return TRACE_TYPE_PARTIAL_LINE; | |
4406 | } | |
bc21b478 | 4407 | |
2c4f035f FW |
4408 | if (iter->trace && iter->trace->print_line) { |
4409 | ret = iter->trace->print_line(iter); | |
4410 | if (ret != TRACE_TYPE_UNHANDLED) | |
4411 | return ret; | |
4412 | } | |
72829bc3 | 4413 | |
09ae7234 SRRH |
4414 | if (iter->ent->type == TRACE_BPUTS && |
4415 | trace_flags & TRACE_ITER_PRINTK && | |
4416 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
4417 | return trace_print_bputs_msg_only(iter); | |
4418 | ||
48ead020 FW |
4419 | if (iter->ent->type == TRACE_BPRINT && |
4420 | trace_flags & TRACE_ITER_PRINTK && | |
4421 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
5ef841f6 | 4422 | return trace_print_bprintk_msg_only(iter); |
48ead020 | 4423 | |
66896a85 FW |
4424 | if (iter->ent->type == TRACE_PRINT && |
4425 | trace_flags & TRACE_ITER_PRINTK && | |
4426 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
5ef841f6 | 4427 | return trace_print_printk_msg_only(iter); |
66896a85 | 4428 | |
cb0f12aa IM |
4429 | if (trace_flags & TRACE_ITER_BIN) |
4430 | return print_bin_fmt(iter); | |
4431 | ||
5e3ca0ec IM |
4432 | if (trace_flags & TRACE_ITER_HEX) |
4433 | return print_hex_fmt(iter); | |
4434 | ||
f9896bf3 IM |
4435 | if (trace_flags & TRACE_ITER_RAW) |
4436 | return print_raw_fmt(iter); | |
4437 | ||
f9896bf3 IM |
4438 | return print_trace_fmt(iter); |
4439 | } | |
4440 | ||
7e9a49ef JO |
4441 | void trace_latency_header(struct seq_file *m) |
4442 | { | |
4443 | struct trace_iterator *iter = m->private; | |
983f938a | 4444 | struct trace_array *tr = iter->tr; |
7e9a49ef JO |
4445 | |
4446 | /* print nothing if the buffers are empty */ | |
4447 | if (trace_empty(iter)) | |
4448 | return; | |
4449 | ||
4450 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) | |
4451 | print_trace_header(m, iter); | |
4452 | ||
983f938a | 4453 | if (!(tr->trace_flags & TRACE_ITER_VERBOSE)) |
7e9a49ef JO |
4454 | print_lat_help_header(m); |
4455 | } | |
4456 | ||
62b915f1 JO |
4457 | void trace_default_header(struct seq_file *m) |
4458 | { | |
4459 | struct trace_iterator *iter = m->private; | |
983f938a SRRH |
4460 | struct trace_array *tr = iter->tr; |
4461 | unsigned long trace_flags = tr->trace_flags; | |
62b915f1 | 4462 | |
f56e7f8e JO |
4463 | if (!(trace_flags & TRACE_ITER_CONTEXT_INFO)) |
4464 | return; | |
4465 | ||
62b915f1 JO |
4466 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) { |
4467 | /* print nothing if the buffers are empty */ | |
4468 | if (trace_empty(iter)) | |
4469 | return; | |
4470 | print_trace_header(m, iter); | |
4471 | if (!(trace_flags & TRACE_ITER_VERBOSE)) | |
4472 | print_lat_help_header(m); | |
4473 | } else { | |
77271ce4 SR |
4474 | if (!(trace_flags & TRACE_ITER_VERBOSE)) { |
4475 | if (trace_flags & TRACE_ITER_IRQ_INFO) | |
1c5eb448 | 4476 | print_func_help_header_irq(iter->array_buffer, |
441dae8f | 4477 | m, trace_flags); |
77271ce4 | 4478 | else |
1c5eb448 | 4479 | print_func_help_header(iter->array_buffer, m, |
441dae8f | 4480 | trace_flags); |
77271ce4 | 4481 | } |
62b915f1 JO |
4482 | } |
4483 | } | |
4484 | ||
e0a413f6 SR |
4485 | static void test_ftrace_alive(struct seq_file *m) |
4486 | { | |
4487 | if (!ftrace_is_dead()) | |
4488 | return; | |
d79ac28f RV |
4489 | seq_puts(m, "# WARNING: FUNCTION TRACING IS CORRUPTED\n" |
4490 | "# MAY BE MISSING FUNCTION EVENTS\n"); | |
e0a413f6 SR |
4491 | } |
4492 | ||
d8741e2e | 4493 | #ifdef CONFIG_TRACER_MAX_TRACE |
f1affcaa | 4494 | static void show_snapshot_main_help(struct seq_file *m) |
d8741e2e | 4495 | { |
d79ac28f RV |
4496 | seq_puts(m, "# echo 0 > snapshot : Clears and frees snapshot buffer\n" |
4497 | "# echo 1 > snapshot : Allocates snapshot buffer, if not already allocated.\n" | |
4498 | "# Takes a snapshot of the main buffer.\n" | |
4499 | "# echo 2 > snapshot : Clears snapshot buffer (but does not allocate or free)\n" | |
4500 | "# (Doesn't have to be '2' works with any number that\n" | |
4501 | "# is not a '0' or '1')\n"); | |
d8741e2e | 4502 | } |
f1affcaa SRRH |
4503 | |
4504 | static void show_snapshot_percpu_help(struct seq_file *m) | |
4505 | { | |
fa6f0cc7 | 4506 | seq_puts(m, "# echo 0 > snapshot : Invalid for per_cpu snapshot file.\n"); |
f1affcaa | 4507 | #ifdef CONFIG_RING_BUFFER_ALLOW_SWAP |
d79ac28f RV |
4508 | seq_puts(m, "# echo 1 > snapshot : Allocates snapshot buffer, if not already allocated.\n" |
4509 | "# Takes a snapshot of the main buffer for this cpu.\n"); | |
f1affcaa | 4510 | #else |
d79ac28f RV |
4511 | seq_puts(m, "# echo 1 > snapshot : Not supported with this kernel.\n" |
4512 | "# Must use main snapshot file to allocate.\n"); | |
f1affcaa | 4513 | #endif |
d79ac28f RV |
4514 | seq_puts(m, "# echo 2 > snapshot : Clears this cpu's snapshot buffer (but does not allocate)\n" |
4515 | "# (Doesn't have to be '2' works with any number that\n" | |
4516 | "# is not a '0' or '1')\n"); | |
f1affcaa SRRH |
4517 | } |
4518 | ||
d8741e2e SRRH |
4519 | static void print_snapshot_help(struct seq_file *m, struct trace_iterator *iter) |
4520 | { | |
45ad21ca | 4521 | if (iter->tr->allocated_snapshot) |
fa6f0cc7 | 4522 | seq_puts(m, "#\n# * Snapshot is allocated *\n#\n"); |
d8741e2e | 4523 | else |
fa6f0cc7 | 4524 | seq_puts(m, "#\n# * Snapshot is freed *\n#\n"); |
d8741e2e | 4525 | |
fa6f0cc7 | 4526 | seq_puts(m, "# Snapshot commands:\n"); |
f1affcaa SRRH |
4527 | if (iter->cpu_file == RING_BUFFER_ALL_CPUS) |
4528 | show_snapshot_main_help(m); | |
4529 | else | |
4530 | show_snapshot_percpu_help(m); | |
d8741e2e SRRH |
4531 | } |
4532 | #else | |
4533 | /* Should never be called */ | |
4534 | static inline void print_snapshot_help(struct seq_file *m, struct trace_iterator *iter) { } | |
4535 | #endif | |
4536 | ||
bc0c38d1 SR |
4537 | static int s_show(struct seq_file *m, void *v) |
4538 | { | |
4539 | struct trace_iterator *iter = v; | |
a63ce5b3 | 4540 | int ret; |
bc0c38d1 SR |
4541 | |
4542 | if (iter->ent == NULL) { | |
4543 | if (iter->tr) { | |
4544 | seq_printf(m, "# tracer: %s\n", iter->trace->name); | |
4545 | seq_puts(m, "#\n"); | |
e0a413f6 | 4546 | test_ftrace_alive(m); |
bc0c38d1 | 4547 | } |
d8741e2e SRRH |
4548 | if (iter->snapshot && trace_empty(iter)) |
4549 | print_snapshot_help(m, iter); | |
4550 | else if (iter->trace && iter->trace->print_header) | |
8bba1bf5 | 4551 | iter->trace->print_header(m); |
62b915f1 JO |
4552 | else |
4553 | trace_default_header(m); | |
4554 | ||
a63ce5b3 SR |
4555 | } else if (iter->leftover) { |
4556 | /* | |
4557 | * If we filled the seq_file buffer earlier, we | |
4558 | * want to just show it now. | |
4559 | */ | |
4560 | ret = trace_print_seq(m, &iter->seq); | |
4561 | ||
4562 | /* ret should this time be zero, but you never know */ | |
4563 | iter->leftover = ret; | |
4564 | ||
bc0c38d1 | 4565 | } else { |
f9896bf3 | 4566 | print_trace_line(iter); |
a63ce5b3 SR |
4567 | ret = trace_print_seq(m, &iter->seq); |
4568 | /* | |
4569 | * If we overflow the seq_file buffer, then it will | |
4570 | * ask us for this data again at start up. | |
4571 | * Use that instead. | |
4572 | * ret is 0 if seq_file write succeeded. | |
4573 | * -1 otherwise. | |
4574 | */ | |
4575 | iter->leftover = ret; | |
bc0c38d1 SR |
4576 | } |
4577 | ||
4578 | return 0; | |
4579 | } | |
4580 | ||
649e9c70 ON |
4581 | /* |
4582 | * Should be used after trace_array_get(), trace_types_lock | |
4583 | * ensures that i_cdev was already initialized. | |
4584 | */ | |
4585 | static inline int tracing_get_cpu(struct inode *inode) | |
4586 | { | |
4587 | if (inode->i_cdev) /* See trace_create_cpu_file() */ | |
4588 | return (long)inode->i_cdev - 1; | |
4589 | return RING_BUFFER_ALL_CPUS; | |
4590 | } | |
4591 | ||
88e9d34c | 4592 | static const struct seq_operations tracer_seq_ops = { |
4bf39a94 IM |
4593 | .start = s_start, |
4594 | .next = s_next, | |
4595 | .stop = s_stop, | |
4596 | .show = s_show, | |
bc0c38d1 SR |
4597 | }; |
4598 | ||
e309b41d | 4599 | static struct trace_iterator * |
6484c71c | 4600 | __tracing_open(struct inode *inode, struct file *file, bool snapshot) |
bc0c38d1 | 4601 | { |
6484c71c | 4602 | struct trace_array *tr = inode->i_private; |
bc0c38d1 | 4603 | struct trace_iterator *iter; |
50e18b94 | 4604 | int cpu; |
bc0c38d1 | 4605 | |
85a2f9b4 SR |
4606 | if (tracing_disabled) |
4607 | return ERR_PTR(-ENODEV); | |
60a11774 | 4608 | |
50e18b94 | 4609 | iter = __seq_open_private(file, &tracer_seq_ops, sizeof(*iter)); |
85a2f9b4 SR |
4610 | if (!iter) |
4611 | return ERR_PTR(-ENOMEM); | |
bc0c38d1 | 4612 | |
72917235 | 4613 | iter->buffer_iter = kcalloc(nr_cpu_ids, sizeof(*iter->buffer_iter), |
6d158a81 | 4614 | GFP_KERNEL); |
93574fcc DC |
4615 | if (!iter->buffer_iter) |
4616 | goto release; | |
4617 | ||
ff895103 SRV |
4618 | /* |
4619 | * trace_find_next_entry() may need to save off iter->ent. | |
4620 | * It will place it into the iter->temp buffer. As most | |
4621 | * events are less than 128, allocate a buffer of that size. | |
4622 | * If one is greater, then trace_find_next_entry() will | |
4623 | * allocate a new buffer to adjust for the bigger iter->ent. | |
4624 | * It's not critical if it fails to get allocated here. | |
4625 | */ | |
4626 | iter->temp = kmalloc(128, GFP_KERNEL); | |
4627 | if (iter->temp) | |
4628 | iter->temp_size = 128; | |
4629 | ||
efbbdaa2 MH |
4630 | /* |
4631 | * trace_event_printf() may need to modify given format | |
4632 | * string to replace %p with %px so that it shows real address | |
4633 | * instead of hash value. However, that is only for the event | |
4634 | * tracing, other tracer may not need. Defer the allocation | |
4635 | * until it is needed. | |
4636 | */ | |
4637 | iter->fmt = NULL; | |
4638 | iter->fmt_size = 0; | |
4639 | ||
d7350c3f FW |
4640 | /* |
4641 | * We make a copy of the current tracer to avoid concurrent | |
4642 | * changes on it while we are reading. | |
4643 | */ | |
bc0c38d1 | 4644 | mutex_lock(&trace_types_lock); |
d7350c3f | 4645 | iter->trace = kzalloc(sizeof(*iter->trace), GFP_KERNEL); |
85a2f9b4 | 4646 | if (!iter->trace) |
d7350c3f | 4647 | goto fail; |
85a2f9b4 | 4648 | |
2b6080f2 | 4649 | *iter->trace = *tr->current_trace; |
d7350c3f | 4650 | |
79f55997 | 4651 | if (!zalloc_cpumask_var(&iter->started, GFP_KERNEL)) |
b0dfa978 FW |
4652 | goto fail; |
4653 | ||
12883efb SRRH |
4654 | iter->tr = tr; |
4655 | ||
4656 | #ifdef CONFIG_TRACER_MAX_TRACE | |
2b6080f2 SR |
4657 | /* Currently only the top directory has a snapshot */ |
4658 | if (tr->current_trace->print_max || snapshot) | |
1c5eb448 | 4659 | iter->array_buffer = &tr->max_buffer; |
bc0c38d1 | 4660 | else |
12883efb | 4661 | #endif |
1c5eb448 | 4662 | iter->array_buffer = &tr->array_buffer; |
debdd57f | 4663 | iter->snapshot = snapshot; |
bc0c38d1 | 4664 | iter->pos = -1; |
6484c71c | 4665 | iter->cpu_file = tracing_get_cpu(inode); |
d7350c3f | 4666 | mutex_init(&iter->mutex); |
bc0c38d1 | 4667 | |
8bba1bf5 | 4668 | /* Notify the tracer early; before we stop tracing. */ |
b3f7a6cd | 4669 | if (iter->trace->open) |
a93751ca | 4670 | iter->trace->open(iter); |
8bba1bf5 | 4671 | |
12ef7d44 | 4672 | /* Annotate start of buffers if we had overruns */ |
1c5eb448 | 4673 | if (ring_buffer_overruns(iter->array_buffer->buffer)) |
12ef7d44 SR |
4674 | iter->iter_flags |= TRACE_FILE_ANNOTATE; |
4675 | ||
8be0709f | 4676 | /* Output in nanoseconds only if we are using a clock in nanoseconds. */ |
58e8eedf | 4677 | if (trace_clocks[tr->clock_id].in_ns) |
8be0709f DS |
4678 | iter->iter_flags |= TRACE_FILE_TIME_IN_NS; |
4679 | ||
06e0a548 SRV |
4680 | /* |
4681 | * If pause-on-trace is enabled, then stop the trace while | |
4682 | * dumping, unless this is the "snapshot" file | |
4683 | */ | |
4684 | if (!iter->snapshot && (tr->trace_flags & TRACE_ITER_PAUSE_ON_TRACE)) | |
2b6080f2 | 4685 | tracing_stop_tr(tr); |
2f26ebd5 | 4686 | |
ae3b5093 | 4687 | if (iter->cpu_file == RING_BUFFER_ALL_CPUS) { |
b04cc6b1 | 4688 | for_each_tracing_cpu(cpu) { |
b04cc6b1 | 4689 | iter->buffer_iter[cpu] = |
1c5eb448 | 4690 | ring_buffer_read_prepare(iter->array_buffer->buffer, |
31b265b3 | 4691 | cpu, GFP_KERNEL); |
72c9ddfd DM |
4692 | } |
4693 | ring_buffer_read_prepare_sync(); | |
4694 | for_each_tracing_cpu(cpu) { | |
4695 | ring_buffer_read_start(iter->buffer_iter[cpu]); | |
2f26ebd5 | 4696 | tracing_iter_reset(iter, cpu); |
b04cc6b1 FW |
4697 | } |
4698 | } else { | |
4699 | cpu = iter->cpu_file; | |
3928a8a2 | 4700 | iter->buffer_iter[cpu] = |
1c5eb448 | 4701 | ring_buffer_read_prepare(iter->array_buffer->buffer, |
31b265b3 | 4702 | cpu, GFP_KERNEL); |
72c9ddfd DM |
4703 | ring_buffer_read_prepare_sync(); |
4704 | ring_buffer_read_start(iter->buffer_iter[cpu]); | |
2f26ebd5 | 4705 | tracing_iter_reset(iter, cpu); |
3928a8a2 SR |
4706 | } |
4707 | ||
bc0c38d1 SR |
4708 | mutex_unlock(&trace_types_lock); |
4709 | ||
bc0c38d1 | 4710 | return iter; |
3928a8a2 | 4711 | |
d7350c3f | 4712 | fail: |
3928a8a2 | 4713 | mutex_unlock(&trace_types_lock); |
d7350c3f | 4714 | kfree(iter->trace); |
ff895103 | 4715 | kfree(iter->temp); |
6d158a81 | 4716 | kfree(iter->buffer_iter); |
93574fcc | 4717 | release: |
50e18b94 JO |
4718 | seq_release_private(inode, file); |
4719 | return ERR_PTR(-ENOMEM); | |
bc0c38d1 SR |
4720 | } |
4721 | ||
4722 | int tracing_open_generic(struct inode *inode, struct file *filp) | |
4723 | { | |
8530dec6 SRV |
4724 | int ret; |
4725 | ||
4726 | ret = tracing_check_open_get_tr(NULL); | |
4727 | if (ret) | |
4728 | return ret; | |
60a11774 | 4729 | |
bc0c38d1 SR |
4730 | filp->private_data = inode->i_private; |
4731 | return 0; | |
4732 | } | |
4733 | ||
2e86421d GB |
4734 | bool tracing_is_disabled(void) |
4735 | { | |
4736 | return (tracing_disabled) ? true: false; | |
4737 | } | |
4738 | ||
7b85af63 SRRH |
4739 | /* |
4740 | * Open and update trace_array ref count. | |
4741 | * Must have the current trace_array passed to it. | |
4742 | */ | |
aa07d71f | 4743 | int tracing_open_generic_tr(struct inode *inode, struct file *filp) |
7b85af63 SRRH |
4744 | { |
4745 | struct trace_array *tr = inode->i_private; | |
8530dec6 | 4746 | int ret; |
7b85af63 | 4747 | |
8530dec6 SRV |
4748 | ret = tracing_check_open_get_tr(tr); |
4749 | if (ret) | |
4750 | return ret; | |
7b85af63 SRRH |
4751 | |
4752 | filp->private_data = inode->i_private; | |
4753 | ||
4754 | return 0; | |
7b85af63 SRRH |
4755 | } |
4756 | ||
4fd27358 | 4757 | static int tracing_release(struct inode *inode, struct file *file) |
bc0c38d1 | 4758 | { |
6484c71c | 4759 | struct trace_array *tr = inode->i_private; |
907f2784 | 4760 | struct seq_file *m = file->private_data; |
4acd4d00 | 4761 | struct trace_iterator *iter; |
3928a8a2 | 4762 | int cpu; |
bc0c38d1 | 4763 | |
ff451961 | 4764 | if (!(file->f_mode & FMODE_READ)) { |
6484c71c | 4765 | trace_array_put(tr); |
4acd4d00 | 4766 | return 0; |
ff451961 | 4767 | } |
4acd4d00 | 4768 | |
6484c71c | 4769 | /* Writes do not use seq_file */ |
4acd4d00 | 4770 | iter = m->private; |
bc0c38d1 | 4771 | mutex_lock(&trace_types_lock); |
a695cb58 | 4772 | |
3928a8a2 SR |
4773 | for_each_tracing_cpu(cpu) { |
4774 | if (iter->buffer_iter[cpu]) | |
4775 | ring_buffer_read_finish(iter->buffer_iter[cpu]); | |
4776 | } | |
4777 | ||
bc0c38d1 SR |
4778 | if (iter->trace && iter->trace->close) |
4779 | iter->trace->close(iter); | |
4780 | ||
06e0a548 | 4781 | if (!iter->snapshot && tr->stop_count) |
debdd57f | 4782 | /* reenable tracing if it was previously enabled */ |
2b6080f2 | 4783 | tracing_start_tr(tr); |
f77d09a3 AL |
4784 | |
4785 | __trace_array_put(tr); | |
4786 | ||
bc0c38d1 SR |
4787 | mutex_unlock(&trace_types_lock); |
4788 | ||
d7350c3f | 4789 | mutex_destroy(&iter->mutex); |
b0dfa978 | 4790 | free_cpumask_var(iter->started); |
efbbdaa2 | 4791 | kfree(iter->fmt); |
ff895103 | 4792 | kfree(iter->temp); |
d7350c3f | 4793 | kfree(iter->trace); |
6d158a81 | 4794 | kfree(iter->buffer_iter); |
50e18b94 | 4795 | seq_release_private(inode, file); |
ff451961 | 4796 | |
bc0c38d1 SR |
4797 | return 0; |
4798 | } | |
4799 | ||
7b85af63 SRRH |
4800 | static int tracing_release_generic_tr(struct inode *inode, struct file *file) |
4801 | { | |
4802 | struct trace_array *tr = inode->i_private; | |
4803 | ||
4804 | trace_array_put(tr); | |
bc0c38d1 SR |
4805 | return 0; |
4806 | } | |
4807 | ||
7b85af63 SRRH |
4808 | static int tracing_single_release_tr(struct inode *inode, struct file *file) |
4809 | { | |
4810 | struct trace_array *tr = inode->i_private; | |
4811 | ||
4812 | trace_array_put(tr); | |
4813 | ||
4814 | return single_release(inode, file); | |
4815 | } | |
4816 | ||
bc0c38d1 SR |
4817 | static int tracing_open(struct inode *inode, struct file *file) |
4818 | { | |
6484c71c | 4819 | struct trace_array *tr = inode->i_private; |
85a2f9b4 | 4820 | struct trace_iterator *iter; |
8530dec6 | 4821 | int ret; |
bc0c38d1 | 4822 | |
8530dec6 SRV |
4823 | ret = tracing_check_open_get_tr(tr); |
4824 | if (ret) | |
4825 | return ret; | |
ff451961 | 4826 | |
4acd4d00 | 4827 | /* If this file was open for write, then erase contents */ |
6484c71c ON |
4828 | if ((file->f_mode & FMODE_WRITE) && (file->f_flags & O_TRUNC)) { |
4829 | int cpu = tracing_get_cpu(inode); | |
1c5eb448 | 4830 | struct array_buffer *trace_buf = &tr->array_buffer; |
8dd33bcb BY |
4831 | |
4832 | #ifdef CONFIG_TRACER_MAX_TRACE | |
4833 | if (tr->current_trace->print_max) | |
4834 | trace_buf = &tr->max_buffer; | |
4835 | #endif | |
6484c71c ON |
4836 | |
4837 | if (cpu == RING_BUFFER_ALL_CPUS) | |
8dd33bcb | 4838 | tracing_reset_online_cpus(trace_buf); |
4acd4d00 | 4839 | else |
a47b53e9 | 4840 | tracing_reset_cpu(trace_buf, cpu); |
4acd4d00 | 4841 | } |
bc0c38d1 | 4842 | |
4acd4d00 | 4843 | if (file->f_mode & FMODE_READ) { |
6484c71c | 4844 | iter = __tracing_open(inode, file, false); |
4acd4d00 SR |
4845 | if (IS_ERR(iter)) |
4846 | ret = PTR_ERR(iter); | |
983f938a | 4847 | else if (tr->trace_flags & TRACE_ITER_LATENCY_FMT) |
4acd4d00 SR |
4848 | iter->iter_flags |= TRACE_FILE_LAT_FMT; |
4849 | } | |
ff451961 SRRH |
4850 | |
4851 | if (ret < 0) | |
4852 | trace_array_put(tr); | |
4853 | ||
bc0c38d1 SR |
4854 | return ret; |
4855 | } | |
4856 | ||
607e2ea1 SRRH |
4857 | /* |
4858 | * Some tracers are not suitable for instance buffers. | |
4859 | * A tracer is always available for the global array (toplevel) | |
4860 | * or if it explicitly states that it is. | |
4861 | */ | |
4862 | static bool | |
4863 | trace_ok_for_array(struct tracer *t, struct trace_array *tr) | |
4864 | { | |
4865 | return (tr->flags & TRACE_ARRAY_FL_GLOBAL) || t->allow_instances; | |
4866 | } | |
4867 | ||
4868 | /* Find the next tracer that this trace array may use */ | |
4869 | static struct tracer * | |
4870 | get_tracer_for_array(struct trace_array *tr, struct tracer *t) | |
4871 | { | |
4872 | while (t && !trace_ok_for_array(t, tr)) | |
4873 | t = t->next; | |
4874 | ||
4875 | return t; | |
4876 | } | |
4877 | ||
e309b41d | 4878 | static void * |
bc0c38d1 SR |
4879 | t_next(struct seq_file *m, void *v, loff_t *pos) |
4880 | { | |
607e2ea1 | 4881 | struct trace_array *tr = m->private; |
f129e965 | 4882 | struct tracer *t = v; |
bc0c38d1 SR |
4883 | |
4884 | (*pos)++; | |
4885 | ||
4886 | if (t) | |
607e2ea1 | 4887 | t = get_tracer_for_array(tr, t->next); |
bc0c38d1 | 4888 | |
bc0c38d1 SR |
4889 | return t; |
4890 | } | |
4891 | ||
4892 | static void *t_start(struct seq_file *m, loff_t *pos) | |
4893 | { | |
607e2ea1 | 4894 | struct trace_array *tr = m->private; |
f129e965 | 4895 | struct tracer *t; |
bc0c38d1 SR |
4896 | loff_t l = 0; |
4897 | ||
4898 | mutex_lock(&trace_types_lock); | |
607e2ea1 SRRH |
4899 | |
4900 | t = get_tracer_for_array(tr, trace_types); | |
4901 | for (; t && l < *pos; t = t_next(m, t, &l)) | |
4902 | ; | |
bc0c38d1 SR |
4903 | |
4904 | return t; | |
4905 | } | |
4906 | ||
4907 | static void t_stop(struct seq_file *m, void *p) | |
4908 | { | |
4909 | mutex_unlock(&trace_types_lock); | |
4910 | } | |
4911 | ||
4912 | static int t_show(struct seq_file *m, void *v) | |
4913 | { | |
4914 | struct tracer *t = v; | |
4915 | ||
4916 | if (!t) | |
4917 | return 0; | |
4918 | ||
fa6f0cc7 | 4919 | seq_puts(m, t->name); |
bc0c38d1 SR |
4920 | if (t->next) |
4921 | seq_putc(m, ' '); | |
4922 | else | |
4923 | seq_putc(m, '\n'); | |
4924 | ||
4925 | return 0; | |
4926 | } | |
4927 | ||
88e9d34c | 4928 | static const struct seq_operations show_traces_seq_ops = { |
4bf39a94 IM |
4929 | .start = t_start, |
4930 | .next = t_next, | |
4931 | .stop = t_stop, | |
4932 | .show = t_show, | |
bc0c38d1 SR |
4933 | }; |
4934 | ||
4935 | static int show_traces_open(struct inode *inode, struct file *file) | |
4936 | { | |
607e2ea1 SRRH |
4937 | struct trace_array *tr = inode->i_private; |
4938 | struct seq_file *m; | |
4939 | int ret; | |
4940 | ||
8530dec6 SRV |
4941 | ret = tracing_check_open_get_tr(tr); |
4942 | if (ret) | |
4943 | return ret; | |
194c2c74 | 4944 | |
607e2ea1 | 4945 | ret = seq_open(file, &show_traces_seq_ops); |
194c2c74 SRV |
4946 | if (ret) { |
4947 | trace_array_put(tr); | |
607e2ea1 | 4948 | return ret; |
194c2c74 | 4949 | } |
607e2ea1 SRRH |
4950 | |
4951 | m = file->private_data; | |
4952 | m->private = tr; | |
4953 | ||
4954 | return 0; | |
bc0c38d1 SR |
4955 | } |
4956 | ||
194c2c74 SRV |
4957 | static int show_traces_release(struct inode *inode, struct file *file) |
4958 | { | |
4959 | struct trace_array *tr = inode->i_private; | |
4960 | ||
4961 | trace_array_put(tr); | |
4962 | return seq_release(inode, file); | |
4963 | } | |
4964 | ||
4acd4d00 SR |
4965 | static ssize_t |
4966 | tracing_write_stub(struct file *filp, const char __user *ubuf, | |
4967 | size_t count, loff_t *ppos) | |
4968 | { | |
4969 | return count; | |
4970 | } | |
4971 | ||
098c879e | 4972 | loff_t tracing_lseek(struct file *file, loff_t offset, int whence) |
364829b1 | 4973 | { |
098c879e SRRH |
4974 | int ret; |
4975 | ||
364829b1 | 4976 | if (file->f_mode & FMODE_READ) |
098c879e | 4977 | ret = seq_lseek(file, offset, whence); |
364829b1 | 4978 | else |
098c879e SRRH |
4979 | file->f_pos = ret = 0; |
4980 | ||
4981 | return ret; | |
364829b1 SP |
4982 | } |
4983 | ||
5e2336a0 | 4984 | static const struct file_operations tracing_fops = { |
4bf39a94 IM |
4985 | .open = tracing_open, |
4986 | .read = seq_read, | |
4acd4d00 | 4987 | .write = tracing_write_stub, |
098c879e | 4988 | .llseek = tracing_lseek, |
4bf39a94 | 4989 | .release = tracing_release, |
bc0c38d1 SR |
4990 | }; |
4991 | ||
5e2336a0 | 4992 | static const struct file_operations show_traces_fops = { |
c7078de1 IM |
4993 | .open = show_traces_open, |
4994 | .read = seq_read, | |
b444786f | 4995 | .llseek = seq_lseek, |
194c2c74 | 4996 | .release = show_traces_release, |
c7078de1 IM |
4997 | }; |
4998 | ||
4999 | static ssize_t | |
5000 | tracing_cpumask_read(struct file *filp, char __user *ubuf, | |
5001 | size_t count, loff_t *ppos) | |
5002 | { | |
ccfe9e42 | 5003 | struct trace_array *tr = file_inode(filp)->i_private; |
90e406f9 | 5004 | char *mask_str; |
36dfe925 | 5005 | int len; |
c7078de1 | 5006 | |
90e406f9 CD |
5007 | len = snprintf(NULL, 0, "%*pb\n", |
5008 | cpumask_pr_args(tr->tracing_cpumask)) + 1; | |
5009 | mask_str = kmalloc(len, GFP_KERNEL); | |
5010 | if (!mask_str) | |
5011 | return -ENOMEM; | |
36dfe925 | 5012 | |
90e406f9 | 5013 | len = snprintf(mask_str, len, "%*pb\n", |
1a40243b TH |
5014 | cpumask_pr_args(tr->tracing_cpumask)); |
5015 | if (len >= count) { | |
36dfe925 IM |
5016 | count = -EINVAL; |
5017 | goto out_err; | |
5018 | } | |
90e406f9 | 5019 | count = simple_read_from_buffer(ubuf, count, ppos, mask_str, len); |
36dfe925 IM |
5020 | |
5021 | out_err: | |
90e406f9 | 5022 | kfree(mask_str); |
c7078de1 IM |
5023 | |
5024 | return count; | |
5025 | } | |
5026 | ||
9d15dbbd MH |
5027 | int tracing_set_cpumask(struct trace_array *tr, |
5028 | cpumask_var_t tracing_cpumask_new) | |
c7078de1 | 5029 | { |
9d15dbbd | 5030 | int cpu; |
c7078de1 | 5031 | |
9d15dbbd MH |
5032 | if (!tr) |
5033 | return -EINVAL; | |
36dfe925 | 5034 | |
a5e25883 | 5035 | local_irq_disable(); |
0b9b12c1 | 5036 | arch_spin_lock(&tr->max_lock); |
ab46428c | 5037 | for_each_tracing_cpu(cpu) { |
36dfe925 IM |
5038 | /* |
5039 | * Increase/decrease the disabled counter if we are | |
5040 | * about to flip a bit in the cpumask: | |
5041 | */ | |
ccfe9e42 | 5042 | if (cpumask_test_cpu(cpu, tr->tracing_cpumask) && |
9e01c1b7 | 5043 | !cpumask_test_cpu(cpu, tracing_cpumask_new)) { |
1c5eb448 SRV |
5044 | atomic_inc(&per_cpu_ptr(tr->array_buffer.data, cpu)->disabled); |
5045 | ring_buffer_record_disable_cpu(tr->array_buffer.buffer, cpu); | |
36dfe925 | 5046 | } |
ccfe9e42 | 5047 | if (!cpumask_test_cpu(cpu, tr->tracing_cpumask) && |
9e01c1b7 | 5048 | cpumask_test_cpu(cpu, tracing_cpumask_new)) { |
1c5eb448 SRV |
5049 | atomic_dec(&per_cpu_ptr(tr->array_buffer.data, cpu)->disabled); |
5050 | ring_buffer_record_enable_cpu(tr->array_buffer.buffer, cpu); | |
36dfe925 IM |
5051 | } |
5052 | } | |
0b9b12c1 | 5053 | arch_spin_unlock(&tr->max_lock); |
a5e25883 | 5054 | local_irq_enable(); |
36dfe925 | 5055 | |
ccfe9e42 | 5056 | cpumask_copy(tr->tracing_cpumask, tracing_cpumask_new); |
9d15dbbd MH |
5057 | |
5058 | return 0; | |
5059 | } | |
5060 | ||
5061 | static ssize_t | |
5062 | tracing_cpumask_write(struct file *filp, const char __user *ubuf, | |
5063 | size_t count, loff_t *ppos) | |
5064 | { | |
5065 | struct trace_array *tr = file_inode(filp)->i_private; | |
5066 | cpumask_var_t tracing_cpumask_new; | |
5067 | int err; | |
5068 | ||
c5e3a411 | 5069 | if (!zalloc_cpumask_var(&tracing_cpumask_new, GFP_KERNEL)) |
9d15dbbd MH |
5070 | return -ENOMEM; |
5071 | ||
5072 | err = cpumask_parse_user(ubuf, count, tracing_cpumask_new); | |
5073 | if (err) | |
5074 | goto err_free; | |
5075 | ||
5076 | err = tracing_set_cpumask(tr, tracing_cpumask_new); | |
5077 | if (err) | |
5078 | goto err_free; | |
5079 | ||
9e01c1b7 | 5080 | free_cpumask_var(tracing_cpumask_new); |
c7078de1 IM |
5081 | |
5082 | return count; | |
36dfe925 | 5083 | |
9d15dbbd | 5084 | err_free: |
215368e8 | 5085 | free_cpumask_var(tracing_cpumask_new); |
36dfe925 IM |
5086 | |
5087 | return err; | |
c7078de1 IM |
5088 | } |
5089 | ||
5e2336a0 | 5090 | static const struct file_operations tracing_cpumask_fops = { |
ccfe9e42 | 5091 | .open = tracing_open_generic_tr, |
c7078de1 IM |
5092 | .read = tracing_cpumask_read, |
5093 | .write = tracing_cpumask_write, | |
ccfe9e42 | 5094 | .release = tracing_release_generic_tr, |
b444786f | 5095 | .llseek = generic_file_llseek, |
bc0c38d1 SR |
5096 | }; |
5097 | ||
fdb372ed | 5098 | static int tracing_trace_options_show(struct seq_file *m, void *v) |
bc0c38d1 | 5099 | { |
d8e83d26 | 5100 | struct tracer_opt *trace_opts; |
2b6080f2 | 5101 | struct trace_array *tr = m->private; |
d8e83d26 | 5102 | u32 tracer_flags; |
d8e83d26 | 5103 | int i; |
adf9f195 | 5104 | |
d8e83d26 | 5105 | mutex_lock(&trace_types_lock); |
2b6080f2 SR |
5106 | tracer_flags = tr->current_trace->flags->val; |
5107 | trace_opts = tr->current_trace->flags->opts; | |
d8e83d26 | 5108 | |
bc0c38d1 | 5109 | for (i = 0; trace_options[i]; i++) { |
983f938a | 5110 | if (tr->trace_flags & (1 << i)) |
fdb372ed | 5111 | seq_printf(m, "%s\n", trace_options[i]); |
bc0c38d1 | 5112 | else |
fdb372ed | 5113 | seq_printf(m, "no%s\n", trace_options[i]); |
bc0c38d1 SR |
5114 | } |
5115 | ||
adf9f195 FW |
5116 | for (i = 0; trace_opts[i].name; i++) { |
5117 | if (tracer_flags & trace_opts[i].bit) | |
fdb372ed | 5118 | seq_printf(m, "%s\n", trace_opts[i].name); |
adf9f195 | 5119 | else |
fdb372ed | 5120 | seq_printf(m, "no%s\n", trace_opts[i].name); |
adf9f195 | 5121 | } |
d8e83d26 | 5122 | mutex_unlock(&trace_types_lock); |
adf9f195 | 5123 | |
fdb372ed | 5124 | return 0; |
bc0c38d1 | 5125 | } |
bc0c38d1 | 5126 | |
8c1a49ae | 5127 | static int __set_tracer_option(struct trace_array *tr, |
8d18eaaf LZ |
5128 | struct tracer_flags *tracer_flags, |
5129 | struct tracer_opt *opts, int neg) | |
5130 | { | |
d39cdd20 | 5131 | struct tracer *trace = tracer_flags->trace; |
8d18eaaf | 5132 | int ret; |
bc0c38d1 | 5133 | |
8c1a49ae | 5134 | ret = trace->set_flag(tr, tracer_flags->val, opts->bit, !neg); |
8d18eaaf LZ |
5135 | if (ret) |
5136 | return ret; | |
5137 | ||
5138 | if (neg) | |
5139 | tracer_flags->val &= ~opts->bit; | |
5140 | else | |
5141 | tracer_flags->val |= opts->bit; | |
5142 | return 0; | |
bc0c38d1 SR |
5143 | } |
5144 | ||
adf9f195 | 5145 | /* Try to assign a tracer specific option */ |
8c1a49ae | 5146 | static int set_tracer_option(struct trace_array *tr, char *cmp, int neg) |
adf9f195 | 5147 | { |
8c1a49ae | 5148 | struct tracer *trace = tr->current_trace; |
7770841e | 5149 | struct tracer_flags *tracer_flags = trace->flags; |
adf9f195 | 5150 | struct tracer_opt *opts = NULL; |
8d18eaaf | 5151 | int i; |
adf9f195 | 5152 | |
7770841e Z |
5153 | for (i = 0; tracer_flags->opts[i].name; i++) { |
5154 | opts = &tracer_flags->opts[i]; | |
adf9f195 | 5155 | |
8d18eaaf | 5156 | if (strcmp(cmp, opts->name) == 0) |
8c1a49ae | 5157 | return __set_tracer_option(tr, trace->flags, opts, neg); |
adf9f195 | 5158 | } |
adf9f195 | 5159 | |
8d18eaaf | 5160 | return -EINVAL; |
adf9f195 FW |
5161 | } |
5162 | ||
613f04a0 SRRH |
5163 | /* Some tracers require overwrite to stay enabled */ |
5164 | int trace_keep_overwrite(struct tracer *tracer, u32 mask, int set) | |
5165 | { | |
5166 | if (tracer->enabled && (mask & TRACE_ITER_OVERWRITE) && !set) | |
5167 | return -1; | |
5168 | ||
5169 | return 0; | |
5170 | } | |
5171 | ||
2b6080f2 | 5172 | int set_tracer_flag(struct trace_array *tr, unsigned int mask, int enabled) |
af4617bd | 5173 | { |
3a53acf1 PS |
5174 | if ((mask == TRACE_ITER_RECORD_TGID) || |
5175 | (mask == TRACE_ITER_RECORD_CMD)) | |
5176 | lockdep_assert_held(&event_mutex); | |
5177 | ||
af4617bd | 5178 | /* do nothing if flag is already set */ |
983f938a | 5179 | if (!!(tr->trace_flags & mask) == !!enabled) |
613f04a0 SRRH |
5180 | return 0; |
5181 | ||
5182 | /* Give the tracer a chance to approve the change */ | |
2b6080f2 | 5183 | if (tr->current_trace->flag_changed) |
bf6065b5 | 5184 | if (tr->current_trace->flag_changed(tr, mask, !!enabled)) |
613f04a0 | 5185 | return -EINVAL; |
af4617bd SR |
5186 | |
5187 | if (enabled) | |
983f938a | 5188 | tr->trace_flags |= mask; |
af4617bd | 5189 | else |
983f938a | 5190 | tr->trace_flags &= ~mask; |
e870e9a1 LZ |
5191 | |
5192 | if (mask == TRACE_ITER_RECORD_CMD) | |
5193 | trace_event_enable_cmd_record(enabled); | |
750912fa | 5194 | |
d914ba37 JF |
5195 | if (mask == TRACE_ITER_RECORD_TGID) { |
5196 | if (!tgid_map) | |
6ee40511 | 5197 | tgid_map = kvcalloc(PID_MAX_DEFAULT + 1, |
6396bb22 | 5198 | sizeof(*tgid_map), |
d914ba37 JF |
5199 | GFP_KERNEL); |
5200 | if (!tgid_map) { | |
5201 | tr->trace_flags &= ~TRACE_ITER_RECORD_TGID; | |
5202 | return -ENOMEM; | |
5203 | } | |
5204 | ||
5205 | trace_event_enable_tgid_record(enabled); | |
5206 | } | |
5207 | ||
c37775d5 SR |
5208 | if (mask == TRACE_ITER_EVENT_FORK) |
5209 | trace_event_follow_fork(tr, enabled); | |
5210 | ||
1e10486f NK |
5211 | if (mask == TRACE_ITER_FUNC_FORK) |
5212 | ftrace_pid_follow_fork(tr, enabled); | |
5213 | ||
80902822 | 5214 | if (mask == TRACE_ITER_OVERWRITE) { |
1c5eb448 | 5215 | ring_buffer_change_overwrite(tr->array_buffer.buffer, enabled); |
80902822 | 5216 | #ifdef CONFIG_TRACER_MAX_TRACE |
12883efb | 5217 | ring_buffer_change_overwrite(tr->max_buffer.buffer, enabled); |
80902822 SRRH |
5218 | #endif |
5219 | } | |
81698831 | 5220 | |
b9f9108c | 5221 | if (mask == TRACE_ITER_PRINTK) { |
81698831 | 5222 | trace_printk_start_stop_comm(enabled); |
b9f9108c SRRH |
5223 | trace_printk_control(enabled); |
5224 | } | |
613f04a0 SRRH |
5225 | |
5226 | return 0; | |
af4617bd SR |
5227 | } |
5228 | ||
9c5b9d3d | 5229 | int trace_set_options(struct trace_array *tr, char *option) |
bc0c38d1 | 5230 | { |
8d18eaaf | 5231 | char *cmp; |
bc0c38d1 | 5232 | int neg = 0; |
591a033d | 5233 | int ret; |
a4d1e688 | 5234 | size_t orig_len = strlen(option); |
3d739c1f | 5235 | int len; |
bc0c38d1 | 5236 | |
7bcfaf54 | 5237 | cmp = strstrip(option); |
bc0c38d1 | 5238 | |
3d739c1f SRV |
5239 | len = str_has_prefix(cmp, "no"); |
5240 | if (len) | |
bc0c38d1 | 5241 | neg = 1; |
3d739c1f SRV |
5242 | |
5243 | cmp += len; | |
bc0c38d1 | 5244 | |
3a53acf1 | 5245 | mutex_lock(&event_mutex); |
69d34da2 SRRH |
5246 | mutex_lock(&trace_types_lock); |
5247 | ||
591a033d | 5248 | ret = match_string(trace_options, -1, cmp); |
adf9f195 | 5249 | /* If no option could be set, test the specific tracer options */ |
591a033d | 5250 | if (ret < 0) |
8c1a49ae | 5251 | ret = set_tracer_option(tr, cmp, neg); |
591a033d YX |
5252 | else |
5253 | ret = set_tracer_flag(tr, 1 << ret, !neg); | |
69d34da2 SRRH |
5254 | |
5255 | mutex_unlock(&trace_types_lock); | |
3a53acf1 | 5256 | mutex_unlock(&event_mutex); |
bc0c38d1 | 5257 | |
a4d1e688 JW |
5258 | /* |
5259 | * If the first trailing whitespace is replaced with '\0' by strstrip, | |
5260 | * turn it back into a space. | |
5261 | */ | |
5262 | if (orig_len > strlen(option)) | |
5263 | option[strlen(option)] = ' '; | |
5264 | ||
7bcfaf54 SR |
5265 | return ret; |
5266 | } | |
5267 | ||
a4d1e688 JW |
5268 | static void __init apply_trace_boot_options(void) |
5269 | { | |
5270 | char *buf = trace_boot_options_buf; | |
5271 | char *option; | |
5272 | ||
5273 | while (true) { | |
5274 | option = strsep(&buf, ","); | |
5275 | ||
5276 | if (!option) | |
5277 | break; | |
a4d1e688 | 5278 | |
43ed3843 SRRH |
5279 | if (*option) |
5280 | trace_set_options(&global_trace, option); | |
a4d1e688 JW |
5281 | |
5282 | /* Put back the comma to allow this to be called again */ | |
5283 | if (buf) | |
5284 | *(buf - 1) = ','; | |
5285 | } | |
5286 | } | |
5287 | ||
7bcfaf54 SR |
5288 | static ssize_t |
5289 | tracing_trace_options_write(struct file *filp, const char __user *ubuf, | |
5290 | size_t cnt, loff_t *ppos) | |
5291 | { | |
2b6080f2 SR |
5292 | struct seq_file *m = filp->private_data; |
5293 | struct trace_array *tr = m->private; | |
7bcfaf54 | 5294 | char buf[64]; |
613f04a0 | 5295 | int ret; |
7bcfaf54 SR |
5296 | |
5297 | if (cnt >= sizeof(buf)) | |
5298 | return -EINVAL; | |
5299 | ||
4afe6495 | 5300 | if (copy_from_user(buf, ubuf, cnt)) |
7bcfaf54 SR |
5301 | return -EFAULT; |
5302 | ||
a8dd2176 SR |
5303 | buf[cnt] = 0; |
5304 | ||
2b6080f2 | 5305 | ret = trace_set_options(tr, buf); |
613f04a0 SRRH |
5306 | if (ret < 0) |
5307 | return ret; | |
7bcfaf54 | 5308 | |
cf8517cf | 5309 | *ppos += cnt; |
bc0c38d1 SR |
5310 | |
5311 | return cnt; | |
5312 | } | |
5313 | ||
fdb372ed LZ |
5314 | static int tracing_trace_options_open(struct inode *inode, struct file *file) |
5315 | { | |
7b85af63 | 5316 | struct trace_array *tr = inode->i_private; |
f77d09a3 | 5317 | int ret; |
7b85af63 | 5318 | |
8530dec6 SRV |
5319 | ret = tracing_check_open_get_tr(tr); |
5320 | if (ret) | |
5321 | return ret; | |
7b85af63 | 5322 | |
f77d09a3 AL |
5323 | ret = single_open(file, tracing_trace_options_show, inode->i_private); |
5324 | if (ret < 0) | |
5325 | trace_array_put(tr); | |
5326 | ||
5327 | return ret; | |
fdb372ed LZ |
5328 | } |
5329 | ||
5e2336a0 | 5330 | static const struct file_operations tracing_iter_fops = { |
fdb372ed LZ |
5331 | .open = tracing_trace_options_open, |
5332 | .read = seq_read, | |
5333 | .llseek = seq_lseek, | |
7b85af63 | 5334 | .release = tracing_single_release_tr, |
ee6bce52 | 5335 | .write = tracing_trace_options_write, |
bc0c38d1 SR |
5336 | }; |
5337 | ||
7bd2f24c IM |
5338 | static const char readme_msg[] = |
5339 | "tracing mini-HOWTO:\n\n" | |
22f45649 SRRH |
5340 | "# echo 0 > tracing_on : quick way to disable tracing\n" |
5341 | "# echo 1 > tracing_on : quick way to re-enable tracing\n\n" | |
5342 | " Important files:\n" | |
5343 | " trace\t\t\t- The static contents of the buffer\n" | |
5344 | "\t\t\t To clear the buffer write into this file: echo > trace\n" | |
5345 | " trace_pipe\t\t- A consuming read to see the contents of the buffer\n" | |
5346 | " current_tracer\t- function and latency tracers\n" | |
5347 | " available_tracers\t- list of configured tracers for current_tracer\n" | |
a8d65579 | 5348 | " error_log\t- error log for failed commands (that support it)\n" |
22f45649 SRRH |
5349 | " buffer_size_kb\t- view and modify size of per cpu buffer\n" |
5350 | " buffer_total_size_kb - view total size of all cpu buffers\n\n" | |
5351 | " trace_clock\t\t-change the clock used to order events\n" | |
5352 | " local: Per cpu clock but may not be synced across CPUs\n" | |
5353 | " global: Synced across CPUs but slows tracing down.\n" | |
5354 | " counter: Not a clock, but just an increment\n" | |
5355 | " uptime: Jiffy counter from time of boot\n" | |
5356 | " perf: Same clock that perf events use\n" | |
5357 | #ifdef CONFIG_X86_64 | |
5358 | " x86-tsc: TSC cycle counter\n" | |
5359 | #endif | |
2c1ea60b TZ |
5360 | "\n timestamp_mode\t-view the mode used to timestamp events\n" |
5361 | " delta: Delta difference against a buffer-wide timestamp\n" | |
5362 | " absolute: Absolute (standalone) timestamp\n" | |
22f45649 | 5363 | "\n trace_marker\t\t- Writes into this file writes into the kernel buffer\n" |
fa32e855 | 5364 | "\n trace_marker_raw\t\t- Writes into this file writes binary data into the kernel buffer\n" |
22f45649 SRRH |
5365 | " tracing_cpumask\t- Limit which CPUs to trace\n" |
5366 | " instances\t\t- Make sub-buffers with: mkdir instances/foo\n" | |
5367 | "\t\t\t Remove sub-buffer with rmdir\n" | |
5368 | " trace_options\t\t- Set format or modify how tracing happens\n" | |
b9416997 | 5369 | "\t\t\t Disable an option by prefixing 'no' to the\n" |
71485c45 | 5370 | "\t\t\t option name\n" |
939c7a4f | 5371 | " saved_cmdlines_size\t- echo command number in here to store comm-pid list\n" |
22f45649 SRRH |
5372 | #ifdef CONFIG_DYNAMIC_FTRACE |
5373 | "\n available_filter_functions - list of functions that can be filtered on\n" | |
71485c45 SRRH |
5374 | " set_ftrace_filter\t- echo function name in here to only trace these\n" |
5375 | "\t\t\t functions\n" | |
60f1d5e3 | 5376 | "\t accepts: func_full_name or glob-matching-pattern\n" |
71485c45 SRRH |
5377 | "\t modules: Can select a group via module\n" |
5378 | "\t Format: :mod:<module-name>\n" | |
5379 | "\t example: echo :mod:ext3 > set_ftrace_filter\n" | |
5380 | "\t triggers: a command to perform when function is hit\n" | |
5381 | "\t Format: <function>:<trigger>[:count]\n" | |
5382 | "\t trigger: traceon, traceoff\n" | |
5383 | "\t\t enable_event:<system>:<event>\n" | |
5384 | "\t\t disable_event:<system>:<event>\n" | |
22f45649 | 5385 | #ifdef CONFIG_STACKTRACE |
71485c45 | 5386 | "\t\t stacktrace\n" |
22f45649 SRRH |
5387 | #endif |
5388 | #ifdef CONFIG_TRACER_SNAPSHOT | |
71485c45 | 5389 | "\t\t snapshot\n" |
22f45649 | 5390 | #endif |
17a280ea SRRH |
5391 | "\t\t dump\n" |
5392 | "\t\t cpudump\n" | |
71485c45 SRRH |
5393 | "\t example: echo do_fault:traceoff > set_ftrace_filter\n" |
5394 | "\t echo do_trap:traceoff:3 > set_ftrace_filter\n" | |
5395 | "\t The first one will disable tracing every time do_fault is hit\n" | |
5396 | "\t The second will disable tracing at most 3 times when do_trap is hit\n" | |
5397 | "\t The first time do trap is hit and it disables tracing, the\n" | |
5398 | "\t counter will decrement to 2. If tracing is already disabled,\n" | |
5399 | "\t the counter will not decrement. It only decrements when the\n" | |
5400 | "\t trigger did work\n" | |
5401 | "\t To remove trigger without count:\n" | |
5402 | "\t echo '!<function>:<trigger> > set_ftrace_filter\n" | |
5403 | "\t To remove trigger with a count:\n" | |
5404 | "\t echo '!<function>:<trigger>:0 > set_ftrace_filter\n" | |
22f45649 | 5405 | " set_ftrace_notrace\t- echo function name in here to never trace.\n" |
71485c45 SRRH |
5406 | "\t accepts: func_full_name, *func_end, func_begin*, *func_middle*\n" |
5407 | "\t modules: Can select a group via module command :mod:\n" | |
5408 | "\t Does not accept triggers\n" | |
22f45649 SRRH |
5409 | #endif /* CONFIG_DYNAMIC_FTRACE */ |
5410 | #ifdef CONFIG_FUNCTION_TRACER | |
71485c45 SRRH |
5411 | " set_ftrace_pid\t- Write pid(s) to only function trace those pids\n" |
5412 | "\t\t (function)\n" | |
b3b1e6ed SRV |
5413 | " set_ftrace_notrace_pid\t- Write pid(s) to not function trace those pids\n" |
5414 | "\t\t (function)\n" | |
22f45649 SRRH |
5415 | #endif |
5416 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER | |
5417 | " set_graph_function\t- Trace the nested calls of a function (function_graph)\n" | |
d048a8c7 | 5418 | " set_graph_notrace\t- Do not trace the nested calls of a function (function_graph)\n" |
22f45649 SRRH |
5419 | " max_graph_depth\t- Trace a limited depth of nested calls (0 is unlimited)\n" |
5420 | #endif | |
5421 | #ifdef CONFIG_TRACER_SNAPSHOT | |
71485c45 SRRH |
5422 | "\n snapshot\t\t- Like 'trace' but shows the content of the static\n" |
5423 | "\t\t\t snapshot buffer. Read the contents for more\n" | |
5424 | "\t\t\t information\n" | |
22f45649 | 5425 | #endif |
991821c8 | 5426 | #ifdef CONFIG_STACK_TRACER |
22f45649 SRRH |
5427 | " stack_trace\t\t- Shows the max stack trace when active\n" |
5428 | " stack_max_size\t- Shows current max stack size that was traced\n" | |
71485c45 SRRH |
5429 | "\t\t\t Write into this file to reset the max size (trigger a\n" |
5430 | "\t\t\t new trace)\n" | |
22f45649 | 5431 | #ifdef CONFIG_DYNAMIC_FTRACE |
71485c45 SRRH |
5432 | " stack_trace_filter\t- Like set_ftrace_filter but limits what stack_trace\n" |
5433 | "\t\t\t traces\n" | |
22f45649 | 5434 | #endif |
991821c8 | 5435 | #endif /* CONFIG_STACK_TRACER */ |
5448d44c | 5436 | #ifdef CONFIG_DYNAMIC_EVENTS |
ca89bc07 | 5437 | " dynamic_events\t\t- Create/append/remove/show the generic dynamic events\n" |
5448d44c MH |
5438 | "\t\t\t Write into this file to define/undefine new trace events.\n" |
5439 | #endif | |
6b0b7551 | 5440 | #ifdef CONFIG_KPROBE_EVENTS |
ca89bc07 | 5441 | " kprobe_events\t\t- Create/append/remove/show the kernel dynamic events\n" |
86425625 MH |
5442 | "\t\t\t Write into this file to define/undefine new trace events.\n" |
5443 | #endif | |
6b0b7551 | 5444 | #ifdef CONFIG_UPROBE_EVENTS |
41af3cf5 | 5445 | " uprobe_events\t\t- Create/append/remove/show the userspace dynamic events\n" |
86425625 MH |
5446 | "\t\t\t Write into this file to define/undefine new trace events.\n" |
5447 | #endif | |
6b0b7551 | 5448 | #if defined(CONFIG_KPROBE_EVENTS) || defined(CONFIG_UPROBE_EVENTS) |
86425625 | 5449 | "\t accepts: event-definitions (one definition per line)\n" |
c3ca46ef MH |
5450 | "\t Format: p[:[<group>/]<event>] <place> [<args>]\n" |
5451 | "\t r[maxactive][:[<group>/]<event>] <place> [<args>]\n" | |
7bbab38d MH |
5452 | #ifdef CONFIG_HIST_TRIGGERS |
5453 | "\t s:[synthetic/]<event> <field> [<field>]\n" | |
5454 | #endif | |
86425625 | 5455 | "\t -:[<group>/]<event>\n" |
6b0b7551 | 5456 | #ifdef CONFIG_KPROBE_EVENTS |
86425625 | 5457 | "\t place: [<module>:]<symbol>[+<offset>]|<memaddr>\n" |
4725cd89 | 5458 | "place (kretprobe): [<module>:]<symbol>[+<offset>]%return|<memaddr>\n" |
86425625 | 5459 | #endif |
6b0b7551 | 5460 | #ifdef CONFIG_UPROBE_EVENTS |
3dd3aae3 | 5461 | " place (uprobe): <path>:<offset>[%return][(ref_ctr_offset)]\n" |
86425625 MH |
5462 | #endif |
5463 | "\t args: <name>=fetcharg[:type]\n" | |
5464 | "\t fetcharg: %<register>, @<address>, @<symbol>[+|-<offset>],\n" | |
a1303af5 | 5465 | #ifdef CONFIG_HAVE_FUNCTION_ARG_ACCESS_API |
e65f7ae7 | 5466 | "\t $stack<index>, $stack, $retval, $comm, $arg<N>,\n" |
a1303af5 | 5467 | #else |
e65f7ae7 | 5468 | "\t $stack<index>, $stack, $retval, $comm,\n" |
a1303af5 | 5469 | #endif |
a42e3c4d | 5470 | "\t +|-[u]<offset>(<fetcharg>), \\imm-value, \\\"imm-string\"\n" |
60c2e0ce | 5471 | "\t type: s8/16/32/64, u8/16/32/64, x8/16/32/64, string, symbol,\n" |
88903c46 | 5472 | "\t b<bit-width>@<bit-offset>/<container-size>, ustring,\n" |
40b53b77 | 5473 | "\t <type>\\[<array-size>\\]\n" |
7bbab38d MH |
5474 | #ifdef CONFIG_HIST_TRIGGERS |
5475 | "\t field: <stype> <name>;\n" | |
5476 | "\t stype: u8/u16/u32/u64, s8/s16/s32/s64, pid_t,\n" | |
5477 | "\t [unsigned] char/int/long\n" | |
5478 | #endif | |
86425625 | 5479 | #endif |
26f25564 TZ |
5480 | " events/\t\t- Directory containing all trace event subsystems:\n" |
5481 | " enable\t\t- Write 0/1 to enable/disable tracing of all events\n" | |
5482 | " events/<system>/\t- Directory containing all trace events for <system>:\n" | |
71485c45 SRRH |
5483 | " enable\t\t- Write 0/1 to enable/disable tracing of all <system>\n" |
5484 | "\t\t\t events\n" | |
26f25564 | 5485 | " filter\t\t- If set, only events passing filter are traced\n" |
71485c45 SRRH |
5486 | " events/<system>/<event>/\t- Directory containing control files for\n" |
5487 | "\t\t\t <event>:\n" | |
26f25564 TZ |
5488 | " enable\t\t- Write 0/1 to enable/disable tracing of <event>\n" |
5489 | " filter\t\t- If set, only events passing filter are traced\n" | |
5490 | " trigger\t\t- If set, a command to perform when event is hit\n" | |
71485c45 SRRH |
5491 | "\t Format: <trigger>[:count][if <filter>]\n" |
5492 | "\t trigger: traceon, traceoff\n" | |
5493 | "\t enable_event:<system>:<event>\n" | |
5494 | "\t disable_event:<system>:<event>\n" | |
d0bad49b TZ |
5495 | #ifdef CONFIG_HIST_TRIGGERS |
5496 | "\t enable_hist:<system>:<event>\n" | |
5497 | "\t disable_hist:<system>:<event>\n" | |
5498 | #endif | |
26f25564 | 5499 | #ifdef CONFIG_STACKTRACE |
71485c45 | 5500 | "\t\t stacktrace\n" |
26f25564 TZ |
5501 | #endif |
5502 | #ifdef CONFIG_TRACER_SNAPSHOT | |
71485c45 | 5503 | "\t\t snapshot\n" |
7ef224d1 TZ |
5504 | #endif |
5505 | #ifdef CONFIG_HIST_TRIGGERS | |
5506 | "\t\t hist (see below)\n" | |
26f25564 | 5507 | #endif |
71485c45 SRRH |
5508 | "\t example: echo traceoff > events/block/block_unplug/trigger\n" |
5509 | "\t echo traceoff:3 > events/block/block_unplug/trigger\n" | |
5510 | "\t echo 'enable_event:kmem:kmalloc:3 if nr_rq > 1' > \\\n" | |
5511 | "\t events/block/block_unplug/trigger\n" | |
5512 | "\t The first disables tracing every time block_unplug is hit.\n" | |
5513 | "\t The second disables tracing the first 3 times block_unplug is hit.\n" | |
5514 | "\t The third enables the kmalloc event the first 3 times block_unplug\n" | |
5515 | "\t is hit and has value of greater than 1 for the 'nr_rq' event field.\n" | |
5516 | "\t Like function triggers, the counter is only decremented if it\n" | |
5517 | "\t enabled or disabled tracing.\n" | |
5518 | "\t To remove a trigger without a count:\n" | |
5519 | "\t echo '!<trigger> > <system>/<event>/trigger\n" | |
5520 | "\t To remove a trigger with a count:\n" | |
5521 | "\t echo '!<trigger>:0 > <system>/<event>/trigger\n" | |
5522 | "\t Filters can be ignored when removing a trigger.\n" | |
7ef224d1 TZ |
5523 | #ifdef CONFIG_HIST_TRIGGERS |
5524 | " hist trigger\t- If set, event hits are aggregated into a hash table\n" | |
76a3b0c8 | 5525 | "\t Format: hist:keys=<field1[,field2,...]>\n" |
f2606835 | 5526 | "\t [:values=<field1[,field2,...]>]\n" |
e62347d2 | 5527 | "\t [:sort=<field1[,field2,...]>]\n" |
7ef224d1 | 5528 | "\t [:size=#entries]\n" |
e86ae9ba | 5529 | "\t [:pause][:continue][:clear]\n" |
5463bfda | 5530 | "\t [:name=histname1]\n" |
c3e49506 | 5531 | "\t [:<handler>.<action>]\n" |
7ef224d1 TZ |
5532 | "\t [if <filter>]\n\n" |
5533 | "\t When a matching event is hit, an entry is added to a hash\n" | |
f2606835 TZ |
5534 | "\t table using the key(s) and value(s) named, and the value of a\n" |
5535 | "\t sum called 'hitcount' is incremented. Keys and values\n" | |
5536 | "\t correspond to fields in the event's format description. Keys\n" | |
69a0200c TZ |
5537 | "\t can be any field, or the special string 'stacktrace'.\n" |
5538 | "\t Compound keys consisting of up to two fields can be specified\n" | |
5539 | "\t by the 'keys' keyword. Values must correspond to numeric\n" | |
5540 | "\t fields. Sort keys consisting of up to two fields can be\n" | |
5541 | "\t specified using the 'sort' keyword. The sort direction can\n" | |
5542 | "\t be modified by appending '.descending' or '.ascending' to a\n" | |
5543 | "\t sort field. The 'size' parameter can be used to specify more\n" | |
5463bfda TZ |
5544 | "\t or fewer than the default 2048 entries for the hashtable size.\n" |
5545 | "\t If a hist trigger is given a name using the 'name' parameter,\n" | |
5546 | "\t its histogram data will be shared with other triggers of the\n" | |
5547 | "\t same name, and trigger hits will update this common data.\n\n" | |
7ef224d1 | 5548 | "\t Reading the 'hist' file for the event will dump the hash\n" |
52a7f16d TZ |
5549 | "\t table in its entirety to stdout. If there are multiple hist\n" |
5550 | "\t triggers attached to an event, there will be a table for each\n" | |
5463bfda TZ |
5551 | "\t trigger in the output. The table displayed for a named\n" |
5552 | "\t trigger will be the same as any other instance having the\n" | |
5553 | "\t same name. The default format used to display a given field\n" | |
5554 | "\t can be modified by appending any of the following modifiers\n" | |
5555 | "\t to the field name, as applicable:\n\n" | |
c6afad49 TZ |
5556 | "\t .hex display a number as a hex value\n" |
5557 | "\t .sym display an address as a symbol\n" | |
6b4827ad | 5558 | "\t .sym-offset display an address as a symbol and offset\n" |
31696198 | 5559 | "\t .execname display a common_pid as a program name\n" |
860f9f6b TZ |
5560 | "\t .syscall display a syscall id as a syscall name\n" |
5561 | "\t .log2 display log2 value rather than raw number\n" | |
5562 | "\t .usecs display a common_timestamp in microseconds\n\n" | |
83e99914 TZ |
5563 | "\t The 'pause' parameter can be used to pause an existing hist\n" |
5564 | "\t trigger or to start a hist trigger but not log any events\n" | |
5565 | "\t until told to do so. 'continue' can be used to start or\n" | |
5566 | "\t restart a paused hist trigger.\n\n" | |
e86ae9ba TZ |
5567 | "\t The 'clear' parameter will clear the contents of a running\n" |
5568 | "\t hist trigger and leave its current paused/active state\n" | |
5569 | "\t unchanged.\n\n" | |
d0bad49b TZ |
5570 | "\t The enable_hist and disable_hist triggers can be used to\n" |
5571 | "\t have one event conditionally start and stop another event's\n" | |
9e5a36a3 | 5572 | "\t already-attached hist trigger. The syntax is analogous to\n" |
c3e49506 TZ |
5573 | "\t the enable_event and disable_event triggers.\n\n" |
5574 | "\t Hist trigger handlers and actions are executed whenever a\n" | |
5575 | "\t a histogram entry is added or updated. They take the form:\n\n" | |
5576 | "\t <handler>.<action>\n\n" | |
5577 | "\t The available handlers are:\n\n" | |
5578 | "\t onmatch(matching.event) - invoke on addition or update\n" | |
dff81f55 TZ |
5579 | "\t onmax(var) - invoke if var exceeds current max\n" |
5580 | "\t onchange(var) - invoke action if var changes\n\n" | |
c3e49506 | 5581 | "\t The available actions are:\n\n" |
e91eefd7 | 5582 | "\t trace(<synthetic_event>,param list) - generate synthetic event\n" |
c3e49506 | 5583 | "\t save(field,...) - save current event fields\n" |
a3785b7e | 5584 | #ifdef CONFIG_TRACER_SNAPSHOT |
1bc36bd4 TZ |
5585 | "\t snapshot() - snapshot the trace buffer\n\n" |
5586 | #endif | |
5587 | #ifdef CONFIG_SYNTH_EVENTS | |
5588 | " events/synthetic_events\t- Create/append/remove/show synthetic events\n" | |
5589 | "\t Write into this file to define/undefine new synthetic events.\n" | |
5590 | "\t example: echo 'myevent u64 lat; char name[]' >> synthetic_events\n" | |
a3785b7e | 5591 | #endif |
7ef224d1 | 5592 | #endif |
7bd2f24c IM |
5593 | ; |
5594 | ||
5595 | static ssize_t | |
5596 | tracing_readme_read(struct file *filp, char __user *ubuf, | |
5597 | size_t cnt, loff_t *ppos) | |
5598 | { | |
5599 | return simple_read_from_buffer(ubuf, cnt, ppos, | |
5600 | readme_msg, strlen(readme_msg)); | |
5601 | } | |
5602 | ||
5e2336a0 | 5603 | static const struct file_operations tracing_readme_fops = { |
c7078de1 IM |
5604 | .open = tracing_open_generic, |
5605 | .read = tracing_readme_read, | |
b444786f | 5606 | .llseek = generic_file_llseek, |
7bd2f24c IM |
5607 | }; |
5608 | ||
99c621d7 MS |
5609 | static void *saved_tgids_next(struct seq_file *m, void *v, loff_t *pos) |
5610 | { | |
5611 | int *ptr = v; | |
5612 | ||
5613 | if (*pos || m->count) | |
5614 | ptr++; | |
5615 | ||
5616 | (*pos)++; | |
5617 | ||
5618 | for (; ptr <= &tgid_map[PID_MAX_DEFAULT]; ptr++) { | |
5619 | if (trace_find_tgid(*ptr)) | |
5620 | return ptr; | |
5621 | } | |
5622 | ||
5623 | return NULL; | |
5624 | } | |
5625 | ||
5626 | static void *saved_tgids_start(struct seq_file *m, loff_t *pos) | |
5627 | { | |
5628 | void *v; | |
5629 | loff_t l = 0; | |
5630 | ||
5631 | if (!tgid_map) | |
5632 | return NULL; | |
5633 | ||
5634 | v = &tgid_map[0]; | |
5635 | while (l <= *pos) { | |
5636 | v = saved_tgids_next(m, v, &l); | |
5637 | if (!v) | |
5638 | return NULL; | |
5639 | } | |
5640 | ||
5641 | return v; | |
5642 | } | |
5643 | ||
5644 | static void saved_tgids_stop(struct seq_file *m, void *v) | |
5645 | { | |
5646 | } | |
5647 | ||
5648 | static int saved_tgids_show(struct seq_file *m, void *v) | |
5649 | { | |
5650 | int pid = (int *)v - tgid_map; | |
5651 | ||
5652 | seq_printf(m, "%d %d\n", pid, trace_find_tgid(pid)); | |
5653 | return 0; | |
5654 | } | |
5655 | ||
5656 | static const struct seq_operations tracing_saved_tgids_seq_ops = { | |
5657 | .start = saved_tgids_start, | |
5658 | .stop = saved_tgids_stop, | |
5659 | .next = saved_tgids_next, | |
5660 | .show = saved_tgids_show, | |
5661 | }; | |
5662 | ||
5663 | static int tracing_saved_tgids_open(struct inode *inode, struct file *filp) | |
5664 | { | |
8530dec6 SRV |
5665 | int ret; |
5666 | ||
5667 | ret = tracing_check_open_get_tr(NULL); | |
5668 | if (ret) | |
5669 | return ret; | |
99c621d7 MS |
5670 | |
5671 | return seq_open(filp, &tracing_saved_tgids_seq_ops); | |
5672 | } | |
5673 | ||
5674 | ||
5675 | static const struct file_operations tracing_saved_tgids_fops = { | |
5676 | .open = tracing_saved_tgids_open, | |
5677 | .read = seq_read, | |
5678 | .llseek = seq_lseek, | |
5679 | .release = seq_release, | |
5680 | }; | |
5681 | ||
42584c81 YY |
5682 | static void *saved_cmdlines_next(struct seq_file *m, void *v, loff_t *pos) |
5683 | { | |
5684 | unsigned int *ptr = v; | |
69abe6a5 | 5685 | |
42584c81 YY |
5686 | if (*pos || m->count) |
5687 | ptr++; | |
69abe6a5 | 5688 | |
42584c81 | 5689 | (*pos)++; |
69abe6a5 | 5690 | |
939c7a4f YY |
5691 | for (; ptr < &savedcmd->map_cmdline_to_pid[savedcmd->cmdline_num]; |
5692 | ptr++) { | |
42584c81 YY |
5693 | if (*ptr == -1 || *ptr == NO_CMDLINE_MAP) |
5694 | continue; | |
69abe6a5 | 5695 | |
42584c81 YY |
5696 | return ptr; |
5697 | } | |
69abe6a5 | 5698 | |
42584c81 YY |
5699 | return NULL; |
5700 | } | |
5701 | ||
5702 | static void *saved_cmdlines_start(struct seq_file *m, loff_t *pos) | |
5703 | { | |
5704 | void *v; | |
5705 | loff_t l = 0; | |
69abe6a5 | 5706 | |
4c27e756 SRRH |
5707 | preempt_disable(); |
5708 | arch_spin_lock(&trace_cmdline_lock); | |
5709 | ||
939c7a4f | 5710 | v = &savedcmd->map_cmdline_to_pid[0]; |
42584c81 YY |
5711 | while (l <= *pos) { |
5712 | v = saved_cmdlines_next(m, v, &l); | |
5713 | if (!v) | |
5714 | return NULL; | |
69abe6a5 AP |
5715 | } |
5716 | ||
42584c81 YY |
5717 | return v; |
5718 | } | |
5719 | ||
5720 | static void saved_cmdlines_stop(struct seq_file *m, void *v) | |
5721 | { | |
4c27e756 SRRH |
5722 | arch_spin_unlock(&trace_cmdline_lock); |
5723 | preempt_enable(); | |
42584c81 | 5724 | } |
69abe6a5 | 5725 | |
42584c81 YY |
5726 | static int saved_cmdlines_show(struct seq_file *m, void *v) |
5727 | { | |
5728 | char buf[TASK_COMM_LEN]; | |
5729 | unsigned int *pid = v; | |
69abe6a5 | 5730 | |
4c27e756 | 5731 | __trace_find_cmdline(*pid, buf); |
42584c81 YY |
5732 | seq_printf(m, "%d %s\n", *pid, buf); |
5733 | return 0; | |
5734 | } | |
5735 | ||
5736 | static const struct seq_operations tracing_saved_cmdlines_seq_ops = { | |
5737 | .start = saved_cmdlines_start, | |
5738 | .next = saved_cmdlines_next, | |
5739 | .stop = saved_cmdlines_stop, | |
5740 | .show = saved_cmdlines_show, | |
5741 | }; | |
5742 | ||
5743 | static int tracing_saved_cmdlines_open(struct inode *inode, struct file *filp) | |
5744 | { | |
8530dec6 SRV |
5745 | int ret; |
5746 | ||
5747 | ret = tracing_check_open_get_tr(NULL); | |
5748 | if (ret) | |
5749 | return ret; | |
42584c81 YY |
5750 | |
5751 | return seq_open(filp, &tracing_saved_cmdlines_seq_ops); | |
69abe6a5 AP |
5752 | } |
5753 | ||
5754 | static const struct file_operations tracing_saved_cmdlines_fops = { | |
42584c81 YY |
5755 | .open = tracing_saved_cmdlines_open, |
5756 | .read = seq_read, | |
5757 | .llseek = seq_lseek, | |
5758 | .release = seq_release, | |
69abe6a5 AP |
5759 | }; |
5760 | ||
939c7a4f YY |
5761 | static ssize_t |
5762 | tracing_saved_cmdlines_size_read(struct file *filp, char __user *ubuf, | |
5763 | size_t cnt, loff_t *ppos) | |
5764 | { | |
5765 | char buf[64]; | |
5766 | int r; | |
5767 | ||
5768 | arch_spin_lock(&trace_cmdline_lock); | |
a6af8fbf | 5769 | r = scnprintf(buf, sizeof(buf), "%u\n", savedcmd->cmdline_num); |
939c7a4f YY |
5770 | arch_spin_unlock(&trace_cmdline_lock); |
5771 | ||
5772 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
5773 | } | |
5774 | ||
5775 | static void free_saved_cmdlines_buffer(struct saved_cmdlines_buffer *s) | |
5776 | { | |
5777 | kfree(s->saved_cmdlines); | |
5778 | kfree(s->map_cmdline_to_pid); | |
5779 | kfree(s); | |
5780 | } | |
5781 | ||
5782 | static int tracing_resize_saved_cmdlines(unsigned int val) | |
5783 | { | |
5784 | struct saved_cmdlines_buffer *s, *savedcmd_temp; | |
5785 | ||
a6af8fbf | 5786 | s = kmalloc(sizeof(*s), GFP_KERNEL); |
939c7a4f YY |
5787 | if (!s) |
5788 | return -ENOMEM; | |
5789 | ||
5790 | if (allocate_cmdlines_buffer(val, s) < 0) { | |
5791 | kfree(s); | |
5792 | return -ENOMEM; | |
5793 | } | |
5794 | ||
5795 | arch_spin_lock(&trace_cmdline_lock); | |
5796 | savedcmd_temp = savedcmd; | |
5797 | savedcmd = s; | |
5798 | arch_spin_unlock(&trace_cmdline_lock); | |
5799 | free_saved_cmdlines_buffer(savedcmd_temp); | |
5800 | ||
5801 | return 0; | |
5802 | } | |
5803 | ||
5804 | static ssize_t | |
5805 | tracing_saved_cmdlines_size_write(struct file *filp, const char __user *ubuf, | |
5806 | size_t cnt, loff_t *ppos) | |
5807 | { | |
5808 | unsigned long val; | |
5809 | int ret; | |
5810 | ||
5811 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); | |
5812 | if (ret) | |
5813 | return ret; | |
5814 | ||
5815 | /* must have at least 1 entry or less than PID_MAX_DEFAULT */ | |
5816 | if (!val || val > PID_MAX_DEFAULT) | |
5817 | return -EINVAL; | |
5818 | ||
5819 | ret = tracing_resize_saved_cmdlines((unsigned int)val); | |
5820 | if (ret < 0) | |
5821 | return ret; | |
5822 | ||
5823 | *ppos += cnt; | |
5824 | ||
5825 | return cnt; | |
5826 | } | |
5827 | ||
5828 | static const struct file_operations tracing_saved_cmdlines_size_fops = { | |
5829 | .open = tracing_open_generic, | |
5830 | .read = tracing_saved_cmdlines_size_read, | |
5831 | .write = tracing_saved_cmdlines_size_write, | |
5832 | }; | |
5833 | ||
681bec03 | 5834 | #ifdef CONFIG_TRACE_EVAL_MAP_FILE |
23bf8cb8 | 5835 | static union trace_eval_map_item * |
f57a4143 | 5836 | update_eval_map(union trace_eval_map_item *ptr) |
9828413d | 5837 | { |
00f4b652 | 5838 | if (!ptr->map.eval_string) { |
9828413d SRRH |
5839 | if (ptr->tail.next) { |
5840 | ptr = ptr->tail.next; | |
5841 | /* Set ptr to the next real item (skip head) */ | |
5842 | ptr++; | |
5843 | } else | |
5844 | return NULL; | |
5845 | } | |
5846 | return ptr; | |
5847 | } | |
5848 | ||
f57a4143 | 5849 | static void *eval_map_next(struct seq_file *m, void *v, loff_t *pos) |
9828413d | 5850 | { |
23bf8cb8 | 5851 | union trace_eval_map_item *ptr = v; |
9828413d SRRH |
5852 | |
5853 | /* | |
5854 | * Paranoid! If ptr points to end, we don't want to increment past it. | |
5855 | * This really should never happen. | |
5856 | */ | |
039958a5 | 5857 | (*pos)++; |
f57a4143 | 5858 | ptr = update_eval_map(ptr); |
9828413d SRRH |
5859 | if (WARN_ON_ONCE(!ptr)) |
5860 | return NULL; | |
5861 | ||
5862 | ptr++; | |
f57a4143 | 5863 | ptr = update_eval_map(ptr); |
9828413d SRRH |
5864 | |
5865 | return ptr; | |
5866 | } | |
5867 | ||
f57a4143 | 5868 | static void *eval_map_start(struct seq_file *m, loff_t *pos) |
9828413d | 5869 | { |
23bf8cb8 | 5870 | union trace_eval_map_item *v; |
9828413d SRRH |
5871 | loff_t l = 0; |
5872 | ||
1793ed93 | 5873 | mutex_lock(&trace_eval_mutex); |
9828413d | 5874 | |
23bf8cb8 | 5875 | v = trace_eval_maps; |
9828413d SRRH |
5876 | if (v) |
5877 | v++; | |
5878 | ||
5879 | while (v && l < *pos) { | |
f57a4143 | 5880 | v = eval_map_next(m, v, &l); |
9828413d SRRH |
5881 | } |
5882 | ||
5883 | return v; | |
5884 | } | |
5885 | ||
f57a4143 | 5886 | static void eval_map_stop(struct seq_file *m, void *v) |
9828413d | 5887 | { |
1793ed93 | 5888 | mutex_unlock(&trace_eval_mutex); |
9828413d SRRH |
5889 | } |
5890 | ||
f57a4143 | 5891 | static int eval_map_show(struct seq_file *m, void *v) |
9828413d | 5892 | { |
23bf8cb8 | 5893 | union trace_eval_map_item *ptr = v; |
9828413d SRRH |
5894 | |
5895 | seq_printf(m, "%s %ld (%s)\n", | |
00f4b652 | 5896 | ptr->map.eval_string, ptr->map.eval_value, |
9828413d SRRH |
5897 | ptr->map.system); |
5898 | ||
5899 | return 0; | |
5900 | } | |
5901 | ||
f57a4143 JL |
5902 | static const struct seq_operations tracing_eval_map_seq_ops = { |
5903 | .start = eval_map_start, | |
5904 | .next = eval_map_next, | |
5905 | .stop = eval_map_stop, | |
5906 | .show = eval_map_show, | |
9828413d SRRH |
5907 | }; |
5908 | ||
f57a4143 | 5909 | static int tracing_eval_map_open(struct inode *inode, struct file *filp) |
9828413d | 5910 | { |
8530dec6 SRV |
5911 | int ret; |
5912 | ||
5913 | ret = tracing_check_open_get_tr(NULL); | |
5914 | if (ret) | |
5915 | return ret; | |
9828413d | 5916 | |
f57a4143 | 5917 | return seq_open(filp, &tracing_eval_map_seq_ops); |
9828413d SRRH |
5918 | } |
5919 | ||
f57a4143 JL |
5920 | static const struct file_operations tracing_eval_map_fops = { |
5921 | .open = tracing_eval_map_open, | |
9828413d SRRH |
5922 | .read = seq_read, |
5923 | .llseek = seq_lseek, | |
5924 | .release = seq_release, | |
5925 | }; | |
5926 | ||
23bf8cb8 | 5927 | static inline union trace_eval_map_item * |
5f60b351 | 5928 | trace_eval_jmp_to_tail(union trace_eval_map_item *ptr) |
9828413d SRRH |
5929 | { |
5930 | /* Return tail of array given the head */ | |
5931 | return ptr + ptr->head.length + 1; | |
5932 | } | |
5933 | ||
5934 | static void | |
f57a4143 | 5935 | trace_insert_eval_map_file(struct module *mod, struct trace_eval_map **start, |
9828413d SRRH |
5936 | int len) |
5937 | { | |
00f4b652 JL |
5938 | struct trace_eval_map **stop; |
5939 | struct trace_eval_map **map; | |
23bf8cb8 JL |
5940 | union trace_eval_map_item *map_array; |
5941 | union trace_eval_map_item *ptr; | |
9828413d SRRH |
5942 | |
5943 | stop = start + len; | |
5944 | ||
5945 | /* | |
23bf8cb8 | 5946 | * The trace_eval_maps contains the map plus a head and tail item, |
9828413d SRRH |
5947 | * where the head holds the module and length of array, and the |
5948 | * tail holds a pointer to the next list. | |
5949 | */ | |
6da2ec56 | 5950 | map_array = kmalloc_array(len + 2, sizeof(*map_array), GFP_KERNEL); |
9828413d | 5951 | if (!map_array) { |
f57a4143 | 5952 | pr_warn("Unable to allocate trace eval mapping\n"); |
9828413d SRRH |
5953 | return; |
5954 | } | |
5955 | ||
1793ed93 | 5956 | mutex_lock(&trace_eval_mutex); |
9828413d | 5957 | |
23bf8cb8 JL |
5958 | if (!trace_eval_maps) |
5959 | trace_eval_maps = map_array; | |
9828413d | 5960 | else { |
23bf8cb8 | 5961 | ptr = trace_eval_maps; |
9828413d | 5962 | for (;;) { |
5f60b351 | 5963 | ptr = trace_eval_jmp_to_tail(ptr); |
9828413d SRRH |
5964 | if (!ptr->tail.next) |
5965 | break; | |
5966 | ptr = ptr->tail.next; | |
5967 | ||
5968 | } | |
5969 | ptr->tail.next = map_array; | |
5970 | } | |
5971 | map_array->head.mod = mod; | |
5972 | map_array->head.length = len; | |
5973 | map_array++; | |
5974 | ||
5975 | for (map = start; (unsigned long)map < (unsigned long)stop; map++) { | |
5976 | map_array->map = **map; | |
5977 | map_array++; | |
5978 | } | |
5979 | memset(map_array, 0, sizeof(*map_array)); | |
5980 | ||
1793ed93 | 5981 | mutex_unlock(&trace_eval_mutex); |
9828413d SRRH |
5982 | } |
5983 | ||
f57a4143 | 5984 | static void trace_create_eval_file(struct dentry *d_tracer) |
9828413d | 5985 | { |
681bec03 | 5986 | trace_create_file("eval_map", 0444, d_tracer, |
f57a4143 | 5987 | NULL, &tracing_eval_map_fops); |
9828413d SRRH |
5988 | } |
5989 | ||
681bec03 | 5990 | #else /* CONFIG_TRACE_EVAL_MAP_FILE */ |
f57a4143 JL |
5991 | static inline void trace_create_eval_file(struct dentry *d_tracer) { } |
5992 | static inline void trace_insert_eval_map_file(struct module *mod, | |
00f4b652 | 5993 | struct trace_eval_map **start, int len) { } |
681bec03 | 5994 | #endif /* !CONFIG_TRACE_EVAL_MAP_FILE */ |
9828413d | 5995 | |
f57a4143 | 5996 | static void trace_insert_eval_map(struct module *mod, |
00f4b652 | 5997 | struct trace_eval_map **start, int len) |
0c564a53 | 5998 | { |
00f4b652 | 5999 | struct trace_eval_map **map; |
0c564a53 SRRH |
6000 | |
6001 | if (len <= 0) | |
6002 | return; | |
6003 | ||
6004 | map = start; | |
6005 | ||
f57a4143 | 6006 | trace_event_eval_update(map, len); |
9828413d | 6007 | |
f57a4143 | 6008 | trace_insert_eval_map_file(mod, start, len); |
0c564a53 SRRH |
6009 | } |
6010 | ||
bc0c38d1 SR |
6011 | static ssize_t |
6012 | tracing_set_trace_read(struct file *filp, char __user *ubuf, | |
6013 | size_t cnt, loff_t *ppos) | |
6014 | { | |
2b6080f2 | 6015 | struct trace_array *tr = filp->private_data; |
ee6c2c1b | 6016 | char buf[MAX_TRACER_SIZE+2]; |
bc0c38d1 SR |
6017 | int r; |
6018 | ||
6019 | mutex_lock(&trace_types_lock); | |
2b6080f2 | 6020 | r = sprintf(buf, "%s\n", tr->current_trace->name); |
bc0c38d1 SR |
6021 | mutex_unlock(&trace_types_lock); |
6022 | ||
4bf39a94 | 6023 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
6024 | } |
6025 | ||
b6f11df2 ACM |
6026 | int tracer_init(struct tracer *t, struct trace_array *tr) |
6027 | { | |
1c5eb448 | 6028 | tracing_reset_online_cpus(&tr->array_buffer); |
b6f11df2 ACM |
6029 | return t->init(tr); |
6030 | } | |
6031 | ||
1c5eb448 | 6032 | static void set_buffer_entries(struct array_buffer *buf, unsigned long val) |
438ced17 VN |
6033 | { |
6034 | int cpu; | |
737223fb | 6035 | |
438ced17 | 6036 | for_each_tracing_cpu(cpu) |
12883efb | 6037 | per_cpu_ptr(buf->data, cpu)->entries = val; |
438ced17 VN |
6038 | } |
6039 | ||
12883efb | 6040 | #ifdef CONFIG_TRACER_MAX_TRACE |
d60da506 | 6041 | /* resize @tr's buffer to the size of @size_tr's entries */ |
1c5eb448 SRV |
6042 | static int resize_buffer_duplicate_size(struct array_buffer *trace_buf, |
6043 | struct array_buffer *size_buf, int cpu_id) | |
d60da506 HT |
6044 | { |
6045 | int cpu, ret = 0; | |
6046 | ||
6047 | if (cpu_id == RING_BUFFER_ALL_CPUS) { | |
6048 | for_each_tracing_cpu(cpu) { | |
12883efb SRRH |
6049 | ret = ring_buffer_resize(trace_buf->buffer, |
6050 | per_cpu_ptr(size_buf->data, cpu)->entries, cpu); | |
d60da506 HT |
6051 | if (ret < 0) |
6052 | break; | |
12883efb SRRH |
6053 | per_cpu_ptr(trace_buf->data, cpu)->entries = |
6054 | per_cpu_ptr(size_buf->data, cpu)->entries; | |
d60da506 HT |
6055 | } |
6056 | } else { | |
12883efb SRRH |
6057 | ret = ring_buffer_resize(trace_buf->buffer, |
6058 | per_cpu_ptr(size_buf->data, cpu_id)->entries, cpu_id); | |
d60da506 | 6059 | if (ret == 0) |
12883efb SRRH |
6060 | per_cpu_ptr(trace_buf->data, cpu_id)->entries = |
6061 | per_cpu_ptr(size_buf->data, cpu_id)->entries; | |
d60da506 HT |
6062 | } |
6063 | ||
6064 | return ret; | |
6065 | } | |
12883efb | 6066 | #endif /* CONFIG_TRACER_MAX_TRACE */ |
d60da506 | 6067 | |
2b6080f2 SR |
6068 | static int __tracing_resize_ring_buffer(struct trace_array *tr, |
6069 | unsigned long size, int cpu) | |
73c5162a SR |
6070 | { |
6071 | int ret; | |
6072 | ||
6073 | /* | |
6074 | * If kernel or user changes the size of the ring buffer | |
a123c52b SR |
6075 | * we use the size that was given, and we can forget about |
6076 | * expanding it later. | |
73c5162a | 6077 | */ |
55034cd6 | 6078 | ring_buffer_expanded = true; |
73c5162a | 6079 | |
b382ede6 | 6080 | /* May be called before buffers are initialized */ |
1c5eb448 | 6081 | if (!tr->array_buffer.buffer) |
b382ede6 SR |
6082 | return 0; |
6083 | ||
1c5eb448 | 6084 | ret = ring_buffer_resize(tr->array_buffer.buffer, size, cpu); |
73c5162a SR |
6085 | if (ret < 0) |
6086 | return ret; | |
6087 | ||
12883efb | 6088 | #ifdef CONFIG_TRACER_MAX_TRACE |
2b6080f2 SR |
6089 | if (!(tr->flags & TRACE_ARRAY_FL_GLOBAL) || |
6090 | !tr->current_trace->use_max_tr) | |
ef710e10 KM |
6091 | goto out; |
6092 | ||
12883efb | 6093 | ret = ring_buffer_resize(tr->max_buffer.buffer, size, cpu); |
73c5162a | 6094 | if (ret < 0) { |
1c5eb448 SRV |
6095 | int r = resize_buffer_duplicate_size(&tr->array_buffer, |
6096 | &tr->array_buffer, cpu); | |
73c5162a | 6097 | if (r < 0) { |
a123c52b SR |
6098 | /* |
6099 | * AARGH! We are left with different | |
6100 | * size max buffer!!!! | |
6101 | * The max buffer is our "snapshot" buffer. | |
6102 | * When a tracer needs a snapshot (one of the | |
6103 | * latency tracers), it swaps the max buffer | |
6104 | * with the saved snap shot. We succeeded to | |
6105 | * update the size of the main buffer, but failed to | |
6106 | * update the size of the max buffer. But when we tried | |
6107 | * to reset the main buffer to the original size, we | |
6108 | * failed there too. This is very unlikely to | |
6109 | * happen, but if it does, warn and kill all | |
6110 | * tracing. | |
6111 | */ | |
73c5162a SR |
6112 | WARN_ON(1); |
6113 | tracing_disabled = 1; | |
6114 | } | |
6115 | return ret; | |
6116 | } | |
6117 | ||
438ced17 | 6118 | if (cpu == RING_BUFFER_ALL_CPUS) |
12883efb | 6119 | set_buffer_entries(&tr->max_buffer, size); |
438ced17 | 6120 | else |
12883efb | 6121 | per_cpu_ptr(tr->max_buffer.data, cpu)->entries = size; |
438ced17 | 6122 | |
ef710e10 | 6123 | out: |
12883efb SRRH |
6124 | #endif /* CONFIG_TRACER_MAX_TRACE */ |
6125 | ||
438ced17 | 6126 | if (cpu == RING_BUFFER_ALL_CPUS) |
1c5eb448 | 6127 | set_buffer_entries(&tr->array_buffer, size); |
438ced17 | 6128 | else |
1c5eb448 | 6129 | per_cpu_ptr(tr->array_buffer.data, cpu)->entries = size; |
73c5162a SR |
6130 | |
6131 | return ret; | |
6132 | } | |
6133 | ||
9c5b9d3d MH |
6134 | ssize_t tracing_resize_ring_buffer(struct trace_array *tr, |
6135 | unsigned long size, int cpu_id) | |
4f271a2a | 6136 | { |
83f40318 | 6137 | int ret = size; |
4f271a2a VN |
6138 | |
6139 | mutex_lock(&trace_types_lock); | |
6140 | ||
438ced17 VN |
6141 | if (cpu_id != RING_BUFFER_ALL_CPUS) { |
6142 | /* make sure, this cpu is enabled in the mask */ | |
6143 | if (!cpumask_test_cpu(cpu_id, tracing_buffer_mask)) { | |
6144 | ret = -EINVAL; | |
6145 | goto out; | |
6146 | } | |
6147 | } | |
4f271a2a | 6148 | |
2b6080f2 | 6149 | ret = __tracing_resize_ring_buffer(tr, size, cpu_id); |
4f271a2a VN |
6150 | if (ret < 0) |
6151 | ret = -ENOMEM; | |
6152 | ||
438ced17 | 6153 | out: |
4f271a2a VN |
6154 | mutex_unlock(&trace_types_lock); |
6155 | ||
6156 | return ret; | |
6157 | } | |
6158 | ||
ef710e10 | 6159 | |
1852fcce SR |
6160 | /** |
6161 | * tracing_update_buffers - used by tracing facility to expand ring buffers | |
6162 | * | |
6163 | * To save on memory when the tracing is never used on a system with it | |
6164 | * configured in. The ring buffers are set to a minimum size. But once | |
6165 | * a user starts to use the tracing facility, then they need to grow | |
6166 | * to their default size. | |
6167 | * | |
6168 | * This function is to be called when a tracer is about to be used. | |
6169 | */ | |
6170 | int tracing_update_buffers(void) | |
6171 | { | |
6172 | int ret = 0; | |
6173 | ||
1027fcb2 | 6174 | mutex_lock(&trace_types_lock); |
1852fcce | 6175 | if (!ring_buffer_expanded) |
2b6080f2 | 6176 | ret = __tracing_resize_ring_buffer(&global_trace, trace_buf_size, |
438ced17 | 6177 | RING_BUFFER_ALL_CPUS); |
1027fcb2 | 6178 | mutex_unlock(&trace_types_lock); |
1852fcce SR |
6179 | |
6180 | return ret; | |
6181 | } | |
6182 | ||
577b785f SR |
6183 | struct trace_option_dentry; |
6184 | ||
37aea98b | 6185 | static void |
2b6080f2 | 6186 | create_trace_option_files(struct trace_array *tr, struct tracer *tracer); |
577b785f | 6187 | |
6b450d25 SRRH |
6188 | /* |
6189 | * Used to clear out the tracer before deletion of an instance. | |
6190 | * Must have trace_types_lock held. | |
6191 | */ | |
6192 | static void tracing_set_nop(struct trace_array *tr) | |
6193 | { | |
6194 | if (tr->current_trace == &nop_trace) | |
6195 | return; | |
6196 | ||
50512ab5 | 6197 | tr->current_trace->enabled--; |
6b450d25 SRRH |
6198 | |
6199 | if (tr->current_trace->reset) | |
6200 | tr->current_trace->reset(tr); | |
6201 | ||
6202 | tr->current_trace = &nop_trace; | |
6203 | } | |
6204 | ||
41d9c0be | 6205 | static void add_tracer_options(struct trace_array *tr, struct tracer *t) |
bc0c38d1 | 6206 | { |
09d23a1d SRRH |
6207 | /* Only enable if the directory has been created already. */ |
6208 | if (!tr->dir) | |
6209 | return; | |
6210 | ||
37aea98b | 6211 | create_trace_option_files(tr, t); |
09d23a1d SRRH |
6212 | } |
6213 | ||
9c5b9d3d | 6214 | int tracing_set_tracer(struct trace_array *tr, const char *buf) |
09d23a1d | 6215 | { |
bc0c38d1 | 6216 | struct tracer *t; |
12883efb | 6217 | #ifdef CONFIG_TRACER_MAX_TRACE |
34600f0e | 6218 | bool had_max_tr; |
12883efb | 6219 | #endif |
d9e54076 | 6220 | int ret = 0; |
bc0c38d1 | 6221 | |
1027fcb2 SR |
6222 | mutex_lock(&trace_types_lock); |
6223 | ||
73c5162a | 6224 | if (!ring_buffer_expanded) { |
2b6080f2 | 6225 | ret = __tracing_resize_ring_buffer(tr, trace_buf_size, |
438ced17 | 6226 | RING_BUFFER_ALL_CPUS); |
73c5162a | 6227 | if (ret < 0) |
59f586db | 6228 | goto out; |
73c5162a SR |
6229 | ret = 0; |
6230 | } | |
6231 | ||
bc0c38d1 SR |
6232 | for (t = trace_types; t; t = t->next) { |
6233 | if (strcmp(t->name, buf) == 0) | |
6234 | break; | |
6235 | } | |
c2931e05 FW |
6236 | if (!t) { |
6237 | ret = -EINVAL; | |
6238 | goto out; | |
6239 | } | |
2b6080f2 | 6240 | if (t == tr->current_trace) |
bc0c38d1 SR |
6241 | goto out; |
6242 | ||
a35873a0 TZ |
6243 | #ifdef CONFIG_TRACER_SNAPSHOT |
6244 | if (t->use_max_tr) { | |
6245 | arch_spin_lock(&tr->max_lock); | |
6246 | if (tr->cond_snapshot) | |
6247 | ret = -EBUSY; | |
6248 | arch_spin_unlock(&tr->max_lock); | |
6249 | if (ret) | |
6250 | goto out; | |
6251 | } | |
6252 | #endif | |
c7b3ae0b ZSZ |
6253 | /* Some tracers won't work on kernel command line */ |
6254 | if (system_state < SYSTEM_RUNNING && t->noboot) { | |
6255 | pr_warn("Tracer '%s' is not allowed on command line, ignored\n", | |
6256 | t->name); | |
6257 | goto out; | |
6258 | } | |
6259 | ||
607e2ea1 SRRH |
6260 | /* Some tracers are only allowed for the top level buffer */ |
6261 | if (!trace_ok_for_array(t, tr)) { | |
6262 | ret = -EINVAL; | |
6263 | goto out; | |
6264 | } | |
6265 | ||
cf6ab6d9 | 6266 | /* If trace pipe files are being read, we can't change the tracer */ |
7ef282e0 | 6267 | if (tr->trace_ref) { |
cf6ab6d9 SRRH |
6268 | ret = -EBUSY; |
6269 | goto out; | |
6270 | } | |
6271 | ||
9f029e83 | 6272 | trace_branch_disable(); |
613f04a0 | 6273 | |
50512ab5 | 6274 | tr->current_trace->enabled--; |
613f04a0 | 6275 | |
2b6080f2 SR |
6276 | if (tr->current_trace->reset) |
6277 | tr->current_trace->reset(tr); | |
34600f0e | 6278 | |
74401729 | 6279 | /* Current trace needs to be nop_trace before synchronize_rcu */ |
2b6080f2 | 6280 | tr->current_trace = &nop_trace; |
34600f0e | 6281 | |
45ad21ca SRRH |
6282 | #ifdef CONFIG_TRACER_MAX_TRACE |
6283 | had_max_tr = tr->allocated_snapshot; | |
34600f0e SR |
6284 | |
6285 | if (had_max_tr && !t->use_max_tr) { | |
6286 | /* | |
6287 | * We need to make sure that the update_max_tr sees that | |
6288 | * current_trace changed to nop_trace to keep it from | |
6289 | * swapping the buffers after we resize it. | |
6290 | * The update_max_tr is called from interrupts disabled | |
6291 | * so a synchronized_sched() is sufficient. | |
6292 | */ | |
74401729 | 6293 | synchronize_rcu(); |
3209cff4 | 6294 | free_snapshot(tr); |
ef710e10 | 6295 | } |
12883efb | 6296 | #endif |
12883efb SRRH |
6297 | |
6298 | #ifdef CONFIG_TRACER_MAX_TRACE | |
34600f0e | 6299 | if (t->use_max_tr && !had_max_tr) { |
2824f503 | 6300 | ret = tracing_alloc_snapshot_instance(tr); |
d60da506 HT |
6301 | if (ret < 0) |
6302 | goto out; | |
ef710e10 | 6303 | } |
12883efb | 6304 | #endif |
577b785f | 6305 | |
1c80025a | 6306 | if (t->init) { |
b6f11df2 | 6307 | ret = tracer_init(t, tr); |
1c80025a FW |
6308 | if (ret) |
6309 | goto out; | |
6310 | } | |
bc0c38d1 | 6311 | |
2b6080f2 | 6312 | tr->current_trace = t; |
50512ab5 | 6313 | tr->current_trace->enabled++; |
9f029e83 | 6314 | trace_branch_enable(tr); |
bc0c38d1 SR |
6315 | out: |
6316 | mutex_unlock(&trace_types_lock); | |
6317 | ||
d9e54076 PZ |
6318 | return ret; |
6319 | } | |
6320 | ||
6321 | static ssize_t | |
6322 | tracing_set_trace_write(struct file *filp, const char __user *ubuf, | |
6323 | size_t cnt, loff_t *ppos) | |
6324 | { | |
607e2ea1 | 6325 | struct trace_array *tr = filp->private_data; |
ee6c2c1b | 6326 | char buf[MAX_TRACER_SIZE+1]; |
d9e54076 PZ |
6327 | int i; |
6328 | size_t ret; | |
e6e7a65a FW |
6329 | int err; |
6330 | ||
6331 | ret = cnt; | |
d9e54076 | 6332 | |
ee6c2c1b LZ |
6333 | if (cnt > MAX_TRACER_SIZE) |
6334 | cnt = MAX_TRACER_SIZE; | |
d9e54076 | 6335 | |
4afe6495 | 6336 | if (copy_from_user(buf, ubuf, cnt)) |
d9e54076 PZ |
6337 | return -EFAULT; |
6338 | ||
6339 | buf[cnt] = 0; | |
6340 | ||
6341 | /* strip ending whitespace. */ | |
6342 | for (i = cnt - 1; i > 0 && isspace(buf[i]); i--) | |
6343 | buf[i] = 0; | |
6344 | ||
607e2ea1 | 6345 | err = tracing_set_tracer(tr, buf); |
e6e7a65a FW |
6346 | if (err) |
6347 | return err; | |
d9e54076 | 6348 | |
cf8517cf | 6349 | *ppos += ret; |
bc0c38d1 | 6350 | |
c2931e05 | 6351 | return ret; |
bc0c38d1 SR |
6352 | } |
6353 | ||
6354 | static ssize_t | |
6508fa76 SF |
6355 | tracing_nsecs_read(unsigned long *ptr, char __user *ubuf, |
6356 | size_t cnt, loff_t *ppos) | |
bc0c38d1 | 6357 | { |
bc0c38d1 SR |
6358 | char buf[64]; |
6359 | int r; | |
6360 | ||
cffae437 | 6361 | r = snprintf(buf, sizeof(buf), "%ld\n", |
bc0c38d1 | 6362 | *ptr == (unsigned long)-1 ? -1 : nsecs_to_usecs(*ptr)); |
cffae437 SR |
6363 | if (r > sizeof(buf)) |
6364 | r = sizeof(buf); | |
4bf39a94 | 6365 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
6366 | } |
6367 | ||
6368 | static ssize_t | |
6508fa76 SF |
6369 | tracing_nsecs_write(unsigned long *ptr, const char __user *ubuf, |
6370 | size_t cnt, loff_t *ppos) | |
bc0c38d1 | 6371 | { |
5e39841c | 6372 | unsigned long val; |
c6caeeb1 | 6373 | int ret; |
bc0c38d1 | 6374 | |
22fe9b54 PH |
6375 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
6376 | if (ret) | |
c6caeeb1 | 6377 | return ret; |
bc0c38d1 SR |
6378 | |
6379 | *ptr = val * 1000; | |
6380 | ||
6381 | return cnt; | |
6382 | } | |
6383 | ||
6508fa76 SF |
6384 | static ssize_t |
6385 | tracing_thresh_read(struct file *filp, char __user *ubuf, | |
6386 | size_t cnt, loff_t *ppos) | |
6387 | { | |
6388 | return tracing_nsecs_read(&tracing_thresh, ubuf, cnt, ppos); | |
6389 | } | |
6390 | ||
6391 | static ssize_t | |
6392 | tracing_thresh_write(struct file *filp, const char __user *ubuf, | |
6393 | size_t cnt, loff_t *ppos) | |
6394 | { | |
6395 | struct trace_array *tr = filp->private_data; | |
6396 | int ret; | |
6397 | ||
6398 | mutex_lock(&trace_types_lock); | |
6399 | ret = tracing_nsecs_write(&tracing_thresh, ubuf, cnt, ppos); | |
6400 | if (ret < 0) | |
6401 | goto out; | |
6402 | ||
6403 | if (tr->current_trace->update_thresh) { | |
6404 | ret = tr->current_trace->update_thresh(tr); | |
6405 | if (ret < 0) | |
6406 | goto out; | |
6407 | } | |
6408 | ||
6409 | ret = cnt; | |
6410 | out: | |
6411 | mutex_unlock(&trace_types_lock); | |
6412 | ||
6413 | return ret; | |
6414 | } | |
6415 | ||
f971cc9a | 6416 | #if defined(CONFIG_TRACER_MAX_TRACE) || defined(CONFIG_HWLAT_TRACER) |
e428abbb | 6417 | |
6508fa76 SF |
6418 | static ssize_t |
6419 | tracing_max_lat_read(struct file *filp, char __user *ubuf, | |
6420 | size_t cnt, loff_t *ppos) | |
6421 | { | |
6422 | return tracing_nsecs_read(filp->private_data, ubuf, cnt, ppos); | |
6423 | } | |
6424 | ||
6425 | static ssize_t | |
6426 | tracing_max_lat_write(struct file *filp, const char __user *ubuf, | |
6427 | size_t cnt, loff_t *ppos) | |
6428 | { | |
6429 | return tracing_nsecs_write(filp->private_data, ubuf, cnt, ppos); | |
6430 | } | |
6431 | ||
e428abbb CG |
6432 | #endif |
6433 | ||
b3806b43 SR |
6434 | static int tracing_open_pipe(struct inode *inode, struct file *filp) |
6435 | { | |
15544209 | 6436 | struct trace_array *tr = inode->i_private; |
b3806b43 | 6437 | struct trace_iterator *iter; |
8530dec6 | 6438 | int ret; |
b3806b43 | 6439 | |
8530dec6 SRV |
6440 | ret = tracing_check_open_get_tr(tr); |
6441 | if (ret) | |
6442 | return ret; | |
7b85af63 | 6443 | |
b04cc6b1 FW |
6444 | mutex_lock(&trace_types_lock); |
6445 | ||
b3806b43 SR |
6446 | /* create a buffer to store the information to pass to userspace */ |
6447 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); | |
b04cc6b1 FW |
6448 | if (!iter) { |
6449 | ret = -ENOMEM; | |
f77d09a3 | 6450 | __trace_array_put(tr); |
b04cc6b1 FW |
6451 | goto out; |
6452 | } | |
b3806b43 | 6453 | |
3a161d99 | 6454 | trace_seq_init(&iter->seq); |
d716ff71 | 6455 | iter->trace = tr->current_trace; |
d7350c3f | 6456 | |
4462344e | 6457 | if (!alloc_cpumask_var(&iter->started, GFP_KERNEL)) { |
b04cc6b1 | 6458 | ret = -ENOMEM; |
d7350c3f | 6459 | goto fail; |
4462344e RR |
6460 | } |
6461 | ||
a309720c | 6462 | /* trace pipe does not show start of buffer */ |
4462344e | 6463 | cpumask_setall(iter->started); |
a309720c | 6464 | |
983f938a | 6465 | if (tr->trace_flags & TRACE_ITER_LATENCY_FMT) |
112f38a7 SR |
6466 | iter->iter_flags |= TRACE_FILE_LAT_FMT; |
6467 | ||
8be0709f | 6468 | /* Output in nanoseconds only if we are using a clock in nanoseconds. */ |
58e8eedf | 6469 | if (trace_clocks[tr->clock_id].in_ns) |
8be0709f DS |
6470 | iter->iter_flags |= TRACE_FILE_TIME_IN_NS; |
6471 | ||
15544209 | 6472 | iter->tr = tr; |
1c5eb448 | 6473 | iter->array_buffer = &tr->array_buffer; |
15544209 | 6474 | iter->cpu_file = tracing_get_cpu(inode); |
d7350c3f | 6475 | mutex_init(&iter->mutex); |
b3806b43 SR |
6476 | filp->private_data = iter; |
6477 | ||
107bad8b SR |
6478 | if (iter->trace->pipe_open) |
6479 | iter->trace->pipe_open(iter); | |
107bad8b | 6480 | |
b444786f | 6481 | nonseekable_open(inode, filp); |
cf6ab6d9 | 6482 | |
7ef282e0 | 6483 | tr->trace_ref++; |
b04cc6b1 FW |
6484 | out: |
6485 | mutex_unlock(&trace_types_lock); | |
6486 | return ret; | |
d7350c3f FW |
6487 | |
6488 | fail: | |
d7350c3f | 6489 | kfree(iter); |
7b85af63 | 6490 | __trace_array_put(tr); |
d7350c3f FW |
6491 | mutex_unlock(&trace_types_lock); |
6492 | return ret; | |
b3806b43 SR |
6493 | } |
6494 | ||
6495 | static int tracing_release_pipe(struct inode *inode, struct file *file) | |
6496 | { | |
6497 | struct trace_iterator *iter = file->private_data; | |
15544209 | 6498 | struct trace_array *tr = inode->i_private; |
b3806b43 | 6499 | |
b04cc6b1 FW |
6500 | mutex_lock(&trace_types_lock); |
6501 | ||
7ef282e0 | 6502 | tr->trace_ref--; |
cf6ab6d9 | 6503 | |
29bf4a5e | 6504 | if (iter->trace->pipe_close) |
c521efd1 SR |
6505 | iter->trace->pipe_close(iter); |
6506 | ||
b04cc6b1 FW |
6507 | mutex_unlock(&trace_types_lock); |
6508 | ||
4462344e | 6509 | free_cpumask_var(iter->started); |
d7350c3f | 6510 | mutex_destroy(&iter->mutex); |
b3806b43 | 6511 | kfree(iter); |
b3806b43 | 6512 | |
7b85af63 SRRH |
6513 | trace_array_put(tr); |
6514 | ||
b3806b43 SR |
6515 | return 0; |
6516 | } | |
6517 | ||
9dd95748 | 6518 | static __poll_t |
cc60cdc9 | 6519 | trace_poll(struct trace_iterator *iter, struct file *filp, poll_table *poll_table) |
2a2cc8f7 | 6520 | { |
983f938a SRRH |
6521 | struct trace_array *tr = iter->tr; |
6522 | ||
15693458 SRRH |
6523 | /* Iterators are static, they should be filled or empty */ |
6524 | if (trace_buffer_iter(iter, iter->cpu_file)) | |
a9a08845 | 6525 | return EPOLLIN | EPOLLRDNORM; |
2a2cc8f7 | 6526 | |
983f938a | 6527 | if (tr->trace_flags & TRACE_ITER_BLOCK) |
2a2cc8f7 SSP |
6528 | /* |
6529 | * Always select as readable when in blocking mode | |
6530 | */ | |
a9a08845 | 6531 | return EPOLLIN | EPOLLRDNORM; |
15693458 | 6532 | else |
1c5eb448 | 6533 | return ring_buffer_poll_wait(iter->array_buffer->buffer, iter->cpu_file, |
15693458 | 6534 | filp, poll_table); |
2a2cc8f7 | 6535 | } |
2a2cc8f7 | 6536 | |
9dd95748 | 6537 | static __poll_t |
cc60cdc9 SR |
6538 | tracing_poll_pipe(struct file *filp, poll_table *poll_table) |
6539 | { | |
6540 | struct trace_iterator *iter = filp->private_data; | |
6541 | ||
6542 | return trace_poll(iter, filp, poll_table); | |
2a2cc8f7 SSP |
6543 | } |
6544 | ||
d716ff71 | 6545 | /* Must be called with iter->mutex held. */ |
ff98781b | 6546 | static int tracing_wait_pipe(struct file *filp) |
b3806b43 SR |
6547 | { |
6548 | struct trace_iterator *iter = filp->private_data; | |
8b8b3683 | 6549 | int ret; |
b3806b43 | 6550 | |
b3806b43 | 6551 | while (trace_empty(iter)) { |
2dc8f095 | 6552 | |
107bad8b | 6553 | if ((filp->f_flags & O_NONBLOCK)) { |
ff98781b | 6554 | return -EAGAIN; |
107bad8b | 6555 | } |
2dc8f095 | 6556 | |
b3806b43 | 6557 | /* |
250bfd3d | 6558 | * We block until we read something and tracing is disabled. |
b3806b43 SR |
6559 | * We still block if tracing is disabled, but we have never |
6560 | * read anything. This allows a user to cat this file, and | |
6561 | * then enable tracing. But after we have read something, | |
6562 | * we give an EOF when tracing is again disabled. | |
6563 | * | |
6564 | * iter->pos will be 0 if we haven't read anything. | |
6565 | */ | |
75df6e68 | 6566 | if (!tracer_tracing_is_on(iter->tr) && iter->pos) |
b3806b43 | 6567 | break; |
f4874261 SRRH |
6568 | |
6569 | mutex_unlock(&iter->mutex); | |
6570 | ||
2c2b0a78 | 6571 | ret = wait_on_pipe(iter, 0); |
f4874261 SRRH |
6572 | |
6573 | mutex_lock(&iter->mutex); | |
6574 | ||
8b8b3683 SRRH |
6575 | if (ret) |
6576 | return ret; | |
b3806b43 SR |
6577 | } |
6578 | ||
ff98781b EGM |
6579 | return 1; |
6580 | } | |
6581 | ||
6582 | /* | |
6583 | * Consumer reader. | |
6584 | */ | |
6585 | static ssize_t | |
6586 | tracing_read_pipe(struct file *filp, char __user *ubuf, | |
6587 | size_t cnt, loff_t *ppos) | |
6588 | { | |
6589 | struct trace_iterator *iter = filp->private_data; | |
6590 | ssize_t sret; | |
6591 | ||
d7350c3f FW |
6592 | /* |
6593 | * Avoid more than one consumer on a single file descriptor | |
6594 | * This is just a matter of traces coherency, the ring buffer itself | |
6595 | * is protected. | |
6596 | */ | |
6597 | mutex_lock(&iter->mutex); | |
1245800c SRRH |
6598 | |
6599 | /* return any leftover data */ | |
6600 | sret = trace_seq_to_user(&iter->seq, ubuf, cnt); | |
6601 | if (sret != -EBUSY) | |
6602 | goto out; | |
6603 | ||
6604 | trace_seq_init(&iter->seq); | |
6605 | ||
ff98781b EGM |
6606 | if (iter->trace->read) { |
6607 | sret = iter->trace->read(iter, filp, ubuf, cnt, ppos); | |
6608 | if (sret) | |
6609 | goto out; | |
6610 | } | |
6611 | ||
6612 | waitagain: | |
6613 | sret = tracing_wait_pipe(filp); | |
6614 | if (sret <= 0) | |
6615 | goto out; | |
6616 | ||
b3806b43 | 6617 | /* stop when tracing is finished */ |
ff98781b EGM |
6618 | if (trace_empty(iter)) { |
6619 | sret = 0; | |
107bad8b | 6620 | goto out; |
ff98781b | 6621 | } |
b3806b43 SR |
6622 | |
6623 | if (cnt >= PAGE_SIZE) | |
6624 | cnt = PAGE_SIZE - 1; | |
6625 | ||
53d0aa77 | 6626 | /* reset all but tr, trace, and overruns */ |
53d0aa77 SR |
6627 | memset(&iter->seq, 0, |
6628 | sizeof(struct trace_iterator) - | |
6629 | offsetof(struct trace_iterator, seq)); | |
ed5467da | 6630 | cpumask_clear(iter->started); |
d303de1f | 6631 | trace_seq_init(&iter->seq); |
4823ed7e | 6632 | iter->pos = -1; |
b3806b43 | 6633 | |
4f535968 | 6634 | trace_event_read_lock(); |
7e53bd42 | 6635 | trace_access_lock(iter->cpu_file); |
955b61e5 | 6636 | while (trace_find_next_entry_inc(iter) != NULL) { |
2c4f035f | 6637 | enum print_line_t ret; |
5ac48378 | 6638 | int save_len = iter->seq.seq.len; |
088b1e42 | 6639 | |
f9896bf3 | 6640 | ret = print_trace_line(iter); |
2c4f035f | 6641 | if (ret == TRACE_TYPE_PARTIAL_LINE) { |
088b1e42 | 6642 | /* don't print partial lines */ |
5ac48378 | 6643 | iter->seq.seq.len = save_len; |
b3806b43 | 6644 | break; |
088b1e42 | 6645 | } |
b91facc3 FW |
6646 | if (ret != TRACE_TYPE_NO_CONSUME) |
6647 | trace_consume(iter); | |
b3806b43 | 6648 | |
5ac48378 | 6649 | if (trace_seq_used(&iter->seq) >= cnt) |
b3806b43 | 6650 | break; |
ee5e51f5 JO |
6651 | |
6652 | /* | |
6653 | * Setting the full flag means we reached the trace_seq buffer | |
6654 | * size and we should leave by partial output condition above. | |
6655 | * One of the trace_seq_* functions is not used properly. | |
6656 | */ | |
6657 | WARN_ONCE(iter->seq.full, "full flag set for trace type %d", | |
6658 | iter->ent->type); | |
b3806b43 | 6659 | } |
7e53bd42 | 6660 | trace_access_unlock(iter->cpu_file); |
4f535968 | 6661 | trace_event_read_unlock(); |
b3806b43 | 6662 | |
b3806b43 | 6663 | /* Now copy what we have to the user */ |
6c6c2796 | 6664 | sret = trace_seq_to_user(&iter->seq, ubuf, cnt); |
5ac48378 | 6665 | if (iter->seq.seq.readpos >= trace_seq_used(&iter->seq)) |
f9520750 | 6666 | trace_seq_init(&iter->seq); |
9ff4b974 PP |
6667 | |
6668 | /* | |
25985edc | 6669 | * If there was nothing to send to user, in spite of consuming trace |
9ff4b974 PP |
6670 | * entries, go back to wait for more entries. |
6671 | */ | |
6c6c2796 | 6672 | if (sret == -EBUSY) |
9ff4b974 | 6673 | goto waitagain; |
b3806b43 | 6674 | |
107bad8b | 6675 | out: |
d7350c3f | 6676 | mutex_unlock(&iter->mutex); |
107bad8b | 6677 | |
6c6c2796 | 6678 | return sret; |
b3806b43 SR |
6679 | } |
6680 | ||
3c56819b EGM |
6681 | static void tracing_spd_release_pipe(struct splice_pipe_desc *spd, |
6682 | unsigned int idx) | |
6683 | { | |
6684 | __free_page(spd->pages[idx]); | |
6685 | } | |
6686 | ||
34cd4998 | 6687 | static size_t |
fa7c7f6e | 6688 | tracing_fill_pipe_page(size_t rem, struct trace_iterator *iter) |
34cd4998 SR |
6689 | { |
6690 | size_t count; | |
74f06bb7 | 6691 | int save_len; |
34cd4998 SR |
6692 | int ret; |
6693 | ||
6694 | /* Seq buffer is page-sized, exactly what we need. */ | |
6695 | for (;;) { | |
74f06bb7 | 6696 | save_len = iter->seq.seq.len; |
34cd4998 | 6697 | ret = print_trace_line(iter); |
74f06bb7 SRRH |
6698 | |
6699 | if (trace_seq_has_overflowed(&iter->seq)) { | |
6700 | iter->seq.seq.len = save_len; | |
34cd4998 SR |
6701 | break; |
6702 | } | |
74f06bb7 SRRH |
6703 | |
6704 | /* | |
6705 | * This should not be hit, because it should only | |
6706 | * be set if the iter->seq overflowed. But check it | |
6707 | * anyway to be safe. | |
6708 | */ | |
34cd4998 | 6709 | if (ret == TRACE_TYPE_PARTIAL_LINE) { |
74f06bb7 SRRH |
6710 | iter->seq.seq.len = save_len; |
6711 | break; | |
6712 | } | |
6713 | ||
5ac48378 | 6714 | count = trace_seq_used(&iter->seq) - save_len; |
74f06bb7 SRRH |
6715 | if (rem < count) { |
6716 | rem = 0; | |
6717 | iter->seq.seq.len = save_len; | |
34cd4998 SR |
6718 | break; |
6719 | } | |
6720 | ||
74e7ff8c LJ |
6721 | if (ret != TRACE_TYPE_NO_CONSUME) |
6722 | trace_consume(iter); | |
34cd4998 | 6723 | rem -= count; |
955b61e5 | 6724 | if (!trace_find_next_entry_inc(iter)) { |
34cd4998 SR |
6725 | rem = 0; |
6726 | iter->ent = NULL; | |
6727 | break; | |
6728 | } | |
6729 | } | |
6730 | ||
6731 | return rem; | |
6732 | } | |
6733 | ||
3c56819b EGM |
6734 | static ssize_t tracing_splice_read_pipe(struct file *filp, |
6735 | loff_t *ppos, | |
6736 | struct pipe_inode_info *pipe, | |
6737 | size_t len, | |
6738 | unsigned int flags) | |
6739 | { | |
35f3d14d JA |
6740 | struct page *pages_def[PIPE_DEF_BUFFERS]; |
6741 | struct partial_page partial_def[PIPE_DEF_BUFFERS]; | |
3c56819b EGM |
6742 | struct trace_iterator *iter = filp->private_data; |
6743 | struct splice_pipe_desc spd = { | |
35f3d14d JA |
6744 | .pages = pages_def, |
6745 | .partial = partial_def, | |
34cd4998 | 6746 | .nr_pages = 0, /* This gets updated below. */ |
047fe360 | 6747 | .nr_pages_max = PIPE_DEF_BUFFERS, |
6797d97a | 6748 | .ops = &default_pipe_buf_ops, |
34cd4998 | 6749 | .spd_release = tracing_spd_release_pipe, |
3c56819b EGM |
6750 | }; |
6751 | ssize_t ret; | |
34cd4998 | 6752 | size_t rem; |
3c56819b EGM |
6753 | unsigned int i; |
6754 | ||
35f3d14d JA |
6755 | if (splice_grow_spd(pipe, &spd)) |
6756 | return -ENOMEM; | |
6757 | ||
d7350c3f | 6758 | mutex_lock(&iter->mutex); |
3c56819b EGM |
6759 | |
6760 | if (iter->trace->splice_read) { | |
6761 | ret = iter->trace->splice_read(iter, filp, | |
6762 | ppos, pipe, len, flags); | |
6763 | if (ret) | |
34cd4998 | 6764 | goto out_err; |
3c56819b EGM |
6765 | } |
6766 | ||
6767 | ret = tracing_wait_pipe(filp); | |
6768 | if (ret <= 0) | |
34cd4998 | 6769 | goto out_err; |
3c56819b | 6770 | |
955b61e5 | 6771 | if (!iter->ent && !trace_find_next_entry_inc(iter)) { |
3c56819b | 6772 | ret = -EFAULT; |
34cd4998 | 6773 | goto out_err; |
3c56819b EGM |
6774 | } |
6775 | ||
4f535968 | 6776 | trace_event_read_lock(); |
7e53bd42 | 6777 | trace_access_lock(iter->cpu_file); |
4f535968 | 6778 | |
3c56819b | 6779 | /* Fill as many pages as possible. */ |
a786c06d | 6780 | for (i = 0, rem = len; i < spd.nr_pages_max && rem; i++) { |
35f3d14d JA |
6781 | spd.pages[i] = alloc_page(GFP_KERNEL); |
6782 | if (!spd.pages[i]) | |
34cd4998 | 6783 | break; |
3c56819b | 6784 | |
fa7c7f6e | 6785 | rem = tracing_fill_pipe_page(rem, iter); |
3c56819b EGM |
6786 | |
6787 | /* Copy the data into the page, so we can start over. */ | |
6788 | ret = trace_seq_to_buffer(&iter->seq, | |
35f3d14d | 6789 | page_address(spd.pages[i]), |
5ac48378 | 6790 | trace_seq_used(&iter->seq)); |
3c56819b | 6791 | if (ret < 0) { |
35f3d14d | 6792 | __free_page(spd.pages[i]); |
3c56819b EGM |
6793 | break; |
6794 | } | |
35f3d14d | 6795 | spd.partial[i].offset = 0; |
5ac48378 | 6796 | spd.partial[i].len = trace_seq_used(&iter->seq); |
3c56819b | 6797 | |
f9520750 | 6798 | trace_seq_init(&iter->seq); |
3c56819b EGM |
6799 | } |
6800 | ||
7e53bd42 | 6801 | trace_access_unlock(iter->cpu_file); |
4f535968 | 6802 | trace_event_read_unlock(); |
d7350c3f | 6803 | mutex_unlock(&iter->mutex); |
3c56819b EGM |
6804 | |
6805 | spd.nr_pages = i; | |
6806 | ||
a29054d9 SRRH |
6807 | if (i) |
6808 | ret = splice_to_pipe(pipe, &spd); | |
6809 | else | |
6810 | ret = 0; | |
35f3d14d | 6811 | out: |
047fe360 | 6812 | splice_shrink_spd(&spd); |
35f3d14d | 6813 | return ret; |
3c56819b | 6814 | |
34cd4998 | 6815 | out_err: |
d7350c3f | 6816 | mutex_unlock(&iter->mutex); |
35f3d14d | 6817 | goto out; |
3c56819b EGM |
6818 | } |
6819 | ||
a98a3c3f SR |
6820 | static ssize_t |
6821 | tracing_entries_read(struct file *filp, char __user *ubuf, | |
6822 | size_t cnt, loff_t *ppos) | |
6823 | { | |
0bc392ee ON |
6824 | struct inode *inode = file_inode(filp); |
6825 | struct trace_array *tr = inode->i_private; | |
6826 | int cpu = tracing_get_cpu(inode); | |
438ced17 VN |
6827 | char buf[64]; |
6828 | int r = 0; | |
6829 | ssize_t ret; | |
a98a3c3f | 6830 | |
db526ca3 | 6831 | mutex_lock(&trace_types_lock); |
438ced17 | 6832 | |
0bc392ee | 6833 | if (cpu == RING_BUFFER_ALL_CPUS) { |
438ced17 VN |
6834 | int cpu, buf_size_same; |
6835 | unsigned long size; | |
6836 | ||
6837 | size = 0; | |
6838 | buf_size_same = 1; | |
6839 | /* check if all cpu sizes are same */ | |
6840 | for_each_tracing_cpu(cpu) { | |
6841 | /* fill in the size from first enabled cpu */ | |
6842 | if (size == 0) | |
1c5eb448 SRV |
6843 | size = per_cpu_ptr(tr->array_buffer.data, cpu)->entries; |
6844 | if (size != per_cpu_ptr(tr->array_buffer.data, cpu)->entries) { | |
438ced17 VN |
6845 | buf_size_same = 0; |
6846 | break; | |
6847 | } | |
6848 | } | |
6849 | ||
6850 | if (buf_size_same) { | |
6851 | if (!ring_buffer_expanded) | |
6852 | r = sprintf(buf, "%lu (expanded: %lu)\n", | |
6853 | size >> 10, | |
6854 | trace_buf_size >> 10); | |
6855 | else | |
6856 | r = sprintf(buf, "%lu\n", size >> 10); | |
6857 | } else | |
6858 | r = sprintf(buf, "X\n"); | |
6859 | } else | |
1c5eb448 | 6860 | r = sprintf(buf, "%lu\n", per_cpu_ptr(tr->array_buffer.data, cpu)->entries >> 10); |
438ced17 | 6861 | |
db526ca3 SR |
6862 | mutex_unlock(&trace_types_lock); |
6863 | ||
438ced17 VN |
6864 | ret = simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
6865 | return ret; | |
a98a3c3f SR |
6866 | } |
6867 | ||
6868 | static ssize_t | |
6869 | tracing_entries_write(struct file *filp, const char __user *ubuf, | |
6870 | size_t cnt, loff_t *ppos) | |
6871 | { | |
0bc392ee ON |
6872 | struct inode *inode = file_inode(filp); |
6873 | struct trace_array *tr = inode->i_private; | |
a98a3c3f | 6874 | unsigned long val; |
4f271a2a | 6875 | int ret; |
a98a3c3f | 6876 | |
22fe9b54 PH |
6877 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
6878 | if (ret) | |
c6caeeb1 | 6879 | return ret; |
a98a3c3f SR |
6880 | |
6881 | /* must have at least 1 entry */ | |
6882 | if (!val) | |
6883 | return -EINVAL; | |
6884 | ||
1696b2b0 SR |
6885 | /* value is in KB */ |
6886 | val <<= 10; | |
0bc392ee | 6887 | ret = tracing_resize_ring_buffer(tr, val, tracing_get_cpu(inode)); |
4f271a2a VN |
6888 | if (ret < 0) |
6889 | return ret; | |
a98a3c3f | 6890 | |
cf8517cf | 6891 | *ppos += cnt; |
a98a3c3f | 6892 | |
4f271a2a VN |
6893 | return cnt; |
6894 | } | |
bf5e6519 | 6895 | |
f81ab074 VN |
6896 | static ssize_t |
6897 | tracing_total_entries_read(struct file *filp, char __user *ubuf, | |
6898 | size_t cnt, loff_t *ppos) | |
6899 | { | |
6900 | struct trace_array *tr = filp->private_data; | |
6901 | char buf[64]; | |
6902 | int r, cpu; | |
6903 | unsigned long size = 0, expanded_size = 0; | |
6904 | ||
6905 | mutex_lock(&trace_types_lock); | |
6906 | for_each_tracing_cpu(cpu) { | |
1c5eb448 | 6907 | size += per_cpu_ptr(tr->array_buffer.data, cpu)->entries >> 10; |
f81ab074 VN |
6908 | if (!ring_buffer_expanded) |
6909 | expanded_size += trace_buf_size >> 10; | |
6910 | } | |
6911 | if (ring_buffer_expanded) | |
6912 | r = sprintf(buf, "%lu\n", size); | |
6913 | else | |
6914 | r = sprintf(buf, "%lu (expanded: %lu)\n", size, expanded_size); | |
6915 | mutex_unlock(&trace_types_lock); | |
6916 | ||
6917 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
6918 | } | |
6919 | ||
4f271a2a VN |
6920 | static ssize_t |
6921 | tracing_free_buffer_write(struct file *filp, const char __user *ubuf, | |
6922 | size_t cnt, loff_t *ppos) | |
6923 | { | |
6924 | /* | |
6925 | * There is no need to read what the user has written, this function | |
6926 | * is just to make sure that there is no error when "echo" is used | |
6927 | */ | |
6928 | ||
6929 | *ppos += cnt; | |
a98a3c3f SR |
6930 | |
6931 | return cnt; | |
6932 | } | |
6933 | ||
4f271a2a VN |
6934 | static int |
6935 | tracing_free_buffer_release(struct inode *inode, struct file *filp) | |
6936 | { | |
2b6080f2 SR |
6937 | struct trace_array *tr = inode->i_private; |
6938 | ||
cf30cf67 | 6939 | /* disable tracing ? */ |
983f938a | 6940 | if (tr->trace_flags & TRACE_ITER_STOP_ON_FREE) |
711e1243 | 6941 | tracer_tracing_off(tr); |
4f271a2a | 6942 | /* resize the ring buffer to 0 */ |
2b6080f2 | 6943 | tracing_resize_ring_buffer(tr, 0, RING_BUFFER_ALL_CPUS); |
4f271a2a | 6944 | |
7b85af63 SRRH |
6945 | trace_array_put(tr); |
6946 | ||
4f271a2a VN |
6947 | return 0; |
6948 | } | |
6949 | ||
5bf9a1ee PP |
6950 | static ssize_t |
6951 | tracing_mark_write(struct file *filp, const char __user *ubuf, | |
6952 | size_t cnt, loff_t *fpos) | |
6953 | { | |
2d71619c | 6954 | struct trace_array *tr = filp->private_data; |
d696b58c | 6955 | struct ring_buffer_event *event; |
3dd80953 | 6956 | enum event_trigger_type tt = ETT_NONE; |
13292494 | 6957 | struct trace_buffer *buffer; |
d696b58c | 6958 | struct print_entry *entry; |
d696b58c | 6959 | ssize_t written; |
d696b58c SR |
6960 | int size; |
6961 | int len; | |
fa32e855 | 6962 | |
656c7f0d | 6963 | /* Used in tracing_mark_raw_write() as well */ |
0f5e5a3a RV |
6964 | #define FAULTED_STR "<faulted>" |
6965 | #define FAULTED_SIZE (sizeof(FAULTED_STR) - 1) /* '\0' is already accounted for */ | |
5bf9a1ee | 6966 | |
c76f0694 | 6967 | if (tracing_disabled) |
5bf9a1ee PP |
6968 | return -EINVAL; |
6969 | ||
983f938a | 6970 | if (!(tr->trace_flags & TRACE_ITER_MARKERS)) |
5224c3a3 MSB |
6971 | return -EINVAL; |
6972 | ||
5bf9a1ee PP |
6973 | if (cnt > TRACE_BUF_SIZE) |
6974 | cnt = TRACE_BUF_SIZE; | |
6975 | ||
d696b58c | 6976 | BUILD_BUG_ON(TRACE_BUF_SIZE >= PAGE_SIZE); |
5bf9a1ee | 6977 | |
656c7f0d | 6978 | size = sizeof(*entry) + cnt + 2; /* add '\0' and possible '\n' */ |
d696b58c | 6979 | |
656c7f0d SRRH |
6980 | /* If less than "<faulted>", then make sure we can still add that */ |
6981 | if (cnt < FAULTED_SIZE) | |
6982 | size += FAULTED_SIZE - cnt; | |
d696b58c | 6983 | |
1c5eb448 | 6984 | buffer = tr->array_buffer.buffer; |
3e9a8aad | 6985 | event = __trace_buffer_lock_reserve(buffer, TRACE_PRINT, size, |
36590c50 | 6986 | tracing_gen_ctx()); |
656c7f0d | 6987 | if (unlikely(!event)) |
d696b58c | 6988 | /* Ring buffer disabled, return as if not open for write */ |
656c7f0d | 6989 | return -EBADF; |
d696b58c SR |
6990 | |
6991 | entry = ring_buffer_event_data(event); | |
6992 | entry->ip = _THIS_IP_; | |
6993 | ||
656c7f0d SRRH |
6994 | len = __copy_from_user_inatomic(&entry->buf, ubuf, cnt); |
6995 | if (len) { | |
0f5e5a3a | 6996 | memcpy(&entry->buf, FAULTED_STR, FAULTED_SIZE); |
656c7f0d SRRH |
6997 | cnt = FAULTED_SIZE; |
6998 | written = -EFAULT; | |
c13d2f7c | 6999 | } else |
656c7f0d | 7000 | written = cnt; |
5bf9a1ee | 7001 | |
3dd80953 SRV |
7002 | if (tr->trace_marker_file && !list_empty(&tr->trace_marker_file->triggers)) { |
7003 | /* do not add \n before testing triggers, but add \0 */ | |
7004 | entry->buf[cnt] = '\0'; | |
b47e3302 | 7005 | tt = event_triggers_call(tr->trace_marker_file, buffer, entry, event); |
3dd80953 SRV |
7006 | } |
7007 | ||
d696b58c SR |
7008 | if (entry->buf[cnt - 1] != '\n') { |
7009 | entry->buf[cnt] = '\n'; | |
7010 | entry->buf[cnt + 1] = '\0'; | |
7011 | } else | |
7012 | entry->buf[cnt] = '\0'; | |
7013 | ||
458999c6 TZ |
7014 | if (static_branch_unlikely(&trace_marker_exports_enabled)) |
7015 | ftrace_exports(event, TRACE_EXPORT_MARKER); | |
7ffbd48d | 7016 | __buffer_unlock_commit(buffer, event); |
5bf9a1ee | 7017 | |
3dd80953 SRV |
7018 | if (tt) |
7019 | event_triggers_post_call(tr->trace_marker_file, tt); | |
7020 | ||
656c7f0d SRRH |
7021 | if (written > 0) |
7022 | *fpos += written; | |
5bf9a1ee | 7023 | |
fa32e855 SR |
7024 | return written; |
7025 | } | |
7026 | ||
7027 | /* Limit it for now to 3K (including tag) */ | |
7028 | #define RAW_DATA_MAX_SIZE (1024*3) | |
7029 | ||
7030 | static ssize_t | |
7031 | tracing_mark_raw_write(struct file *filp, const char __user *ubuf, | |
7032 | size_t cnt, loff_t *fpos) | |
7033 | { | |
7034 | struct trace_array *tr = filp->private_data; | |
7035 | struct ring_buffer_event *event; | |
13292494 | 7036 | struct trace_buffer *buffer; |
fa32e855 | 7037 | struct raw_data_entry *entry; |
fa32e855 | 7038 | ssize_t written; |
fa32e855 SR |
7039 | int size; |
7040 | int len; | |
7041 | ||
656c7f0d SRRH |
7042 | #define FAULT_SIZE_ID (FAULTED_SIZE + sizeof(int)) |
7043 | ||
fa32e855 SR |
7044 | if (tracing_disabled) |
7045 | return -EINVAL; | |
7046 | ||
7047 | if (!(tr->trace_flags & TRACE_ITER_MARKERS)) | |
7048 | return -EINVAL; | |
7049 | ||
7050 | /* The marker must at least have a tag id */ | |
7051 | if (cnt < sizeof(unsigned int) || cnt > RAW_DATA_MAX_SIZE) | |
7052 | return -EINVAL; | |
7053 | ||
7054 | if (cnt > TRACE_BUF_SIZE) | |
7055 | cnt = TRACE_BUF_SIZE; | |
7056 | ||
7057 | BUILD_BUG_ON(TRACE_BUF_SIZE >= PAGE_SIZE); | |
7058 | ||
fa32e855 | 7059 | size = sizeof(*entry) + cnt; |
656c7f0d SRRH |
7060 | if (cnt < FAULT_SIZE_ID) |
7061 | size += FAULT_SIZE_ID - cnt; | |
7062 | ||
1c5eb448 | 7063 | buffer = tr->array_buffer.buffer; |
3e9a8aad | 7064 | event = __trace_buffer_lock_reserve(buffer, TRACE_RAW_DATA, size, |
36590c50 | 7065 | tracing_gen_ctx()); |
656c7f0d | 7066 | if (!event) |
fa32e855 | 7067 | /* Ring buffer disabled, return as if not open for write */ |
656c7f0d | 7068 | return -EBADF; |
fa32e855 SR |
7069 | |
7070 | entry = ring_buffer_event_data(event); | |
7071 | ||
656c7f0d SRRH |
7072 | len = __copy_from_user_inatomic(&entry->id, ubuf, cnt); |
7073 | if (len) { | |
7074 | entry->id = -1; | |
0f5e5a3a | 7075 | memcpy(&entry->buf, FAULTED_STR, FAULTED_SIZE); |
656c7f0d | 7076 | written = -EFAULT; |
fa32e855 | 7077 | } else |
656c7f0d | 7078 | written = cnt; |
fa32e855 SR |
7079 | |
7080 | __buffer_unlock_commit(buffer, event); | |
7081 | ||
656c7f0d SRRH |
7082 | if (written > 0) |
7083 | *fpos += written; | |
1aa54bca MS |
7084 | |
7085 | return written; | |
5bf9a1ee PP |
7086 | } |
7087 | ||
13f16d20 | 7088 | static int tracing_clock_show(struct seq_file *m, void *v) |
5079f326 | 7089 | { |
2b6080f2 | 7090 | struct trace_array *tr = m->private; |
5079f326 Z |
7091 | int i; |
7092 | ||
7093 | for (i = 0; i < ARRAY_SIZE(trace_clocks); i++) | |
13f16d20 | 7094 | seq_printf(m, |
5079f326 | 7095 | "%s%s%s%s", i ? " " : "", |
2b6080f2 SR |
7096 | i == tr->clock_id ? "[" : "", trace_clocks[i].name, |
7097 | i == tr->clock_id ? "]" : ""); | |
13f16d20 | 7098 | seq_putc(m, '\n'); |
5079f326 | 7099 | |
13f16d20 | 7100 | return 0; |
5079f326 Z |
7101 | } |
7102 | ||
d71bd34d | 7103 | int tracing_set_clock(struct trace_array *tr, const char *clockstr) |
5079f326 | 7104 | { |
5079f326 Z |
7105 | int i; |
7106 | ||
5079f326 Z |
7107 | for (i = 0; i < ARRAY_SIZE(trace_clocks); i++) { |
7108 | if (strcmp(trace_clocks[i].name, clockstr) == 0) | |
7109 | break; | |
7110 | } | |
7111 | if (i == ARRAY_SIZE(trace_clocks)) | |
7112 | return -EINVAL; | |
7113 | ||
5079f326 Z |
7114 | mutex_lock(&trace_types_lock); |
7115 | ||
2b6080f2 SR |
7116 | tr->clock_id = i; |
7117 | ||
1c5eb448 | 7118 | ring_buffer_set_clock(tr->array_buffer.buffer, trace_clocks[i].func); |
5079f326 | 7119 | |
60303ed3 DS |
7120 | /* |
7121 | * New clock may not be consistent with the previous clock. | |
7122 | * Reset the buffer so that it doesn't have incomparable timestamps. | |
7123 | */ | |
1c5eb448 | 7124 | tracing_reset_online_cpus(&tr->array_buffer); |
12883efb SRRH |
7125 | |
7126 | #ifdef CONFIG_TRACER_MAX_TRACE | |
170b3b10 | 7127 | if (tr->max_buffer.buffer) |
12883efb | 7128 | ring_buffer_set_clock(tr->max_buffer.buffer, trace_clocks[i].func); |
9457158b | 7129 | tracing_reset_online_cpus(&tr->max_buffer); |
12883efb | 7130 | #endif |
60303ed3 | 7131 | |
5079f326 Z |
7132 | mutex_unlock(&trace_types_lock); |
7133 | ||
e1e232ca SR |
7134 | return 0; |
7135 | } | |
7136 | ||
7137 | static ssize_t tracing_clock_write(struct file *filp, const char __user *ubuf, | |
7138 | size_t cnt, loff_t *fpos) | |
7139 | { | |
7140 | struct seq_file *m = filp->private_data; | |
7141 | struct trace_array *tr = m->private; | |
7142 | char buf[64]; | |
7143 | const char *clockstr; | |
7144 | int ret; | |
7145 | ||
7146 | if (cnt >= sizeof(buf)) | |
7147 | return -EINVAL; | |
7148 | ||
4afe6495 | 7149 | if (copy_from_user(buf, ubuf, cnt)) |
e1e232ca SR |
7150 | return -EFAULT; |
7151 | ||
7152 | buf[cnt] = 0; | |
7153 | ||
7154 | clockstr = strstrip(buf); | |
7155 | ||
7156 | ret = tracing_set_clock(tr, clockstr); | |
7157 | if (ret) | |
7158 | return ret; | |
7159 | ||
5079f326 Z |
7160 | *fpos += cnt; |
7161 | ||
7162 | return cnt; | |
7163 | } | |
7164 | ||
13f16d20 LZ |
7165 | static int tracing_clock_open(struct inode *inode, struct file *file) |
7166 | { | |
7b85af63 SRRH |
7167 | struct trace_array *tr = inode->i_private; |
7168 | int ret; | |
7169 | ||
8530dec6 SRV |
7170 | ret = tracing_check_open_get_tr(tr); |
7171 | if (ret) | |
7172 | return ret; | |
7b85af63 SRRH |
7173 | |
7174 | ret = single_open(file, tracing_clock_show, inode->i_private); | |
7175 | if (ret < 0) | |
7176 | trace_array_put(tr); | |
7177 | ||
7178 | return ret; | |
13f16d20 LZ |
7179 | } |
7180 | ||
2c1ea60b TZ |
7181 | static int tracing_time_stamp_mode_show(struct seq_file *m, void *v) |
7182 | { | |
7183 | struct trace_array *tr = m->private; | |
7184 | ||
7185 | mutex_lock(&trace_types_lock); | |
7186 | ||
1c5eb448 | 7187 | if (ring_buffer_time_stamp_abs(tr->array_buffer.buffer)) |
2c1ea60b TZ |
7188 | seq_puts(m, "delta [absolute]\n"); |
7189 | else | |
7190 | seq_puts(m, "[delta] absolute\n"); | |
7191 | ||
7192 | mutex_unlock(&trace_types_lock); | |
7193 | ||
7194 | return 0; | |
7195 | } | |
7196 | ||
7197 | static int tracing_time_stamp_mode_open(struct inode *inode, struct file *file) | |
7198 | { | |
7199 | struct trace_array *tr = inode->i_private; | |
7200 | int ret; | |
7201 | ||
8530dec6 SRV |
7202 | ret = tracing_check_open_get_tr(tr); |
7203 | if (ret) | |
7204 | return ret; | |
2c1ea60b TZ |
7205 | |
7206 | ret = single_open(file, tracing_time_stamp_mode_show, inode->i_private); | |
7207 | if (ret < 0) | |
7208 | trace_array_put(tr); | |
7209 | ||
7210 | return ret; | |
7211 | } | |
7212 | ||
d8279bfc SRV |
7213 | u64 tracing_event_time_stamp(struct trace_buffer *buffer, struct ring_buffer_event *rbe) |
7214 | { | |
7215 | if (rbe == this_cpu_read(trace_buffered_event)) | |
f3ef7202 | 7216 | return ring_buffer_time_stamp(buffer); |
d8279bfc SRV |
7217 | |
7218 | return ring_buffer_event_time_stamp(buffer, rbe); | |
7219 | } | |
7220 | ||
b94bc80d SRV |
7221 | /* |
7222 | * Set or disable using the per CPU trace_buffer_event when possible. | |
7223 | */ | |
7224 | int tracing_set_filter_buffering(struct trace_array *tr, bool set) | |
00b41452 TZ |
7225 | { |
7226 | int ret = 0; | |
7227 | ||
7228 | mutex_lock(&trace_types_lock); | |
7229 | ||
b94bc80d | 7230 | if (set && tr->no_filter_buffering_ref++) |
00b41452 TZ |
7231 | goto out; |
7232 | ||
b94bc80d SRV |
7233 | if (!set) { |
7234 | if (WARN_ON_ONCE(!tr->no_filter_buffering_ref)) { | |
00b41452 TZ |
7235 | ret = -EINVAL; |
7236 | goto out; | |
7237 | } | |
7238 | ||
b94bc80d | 7239 | --tr->no_filter_buffering_ref; |
00b41452 | 7240 | } |
00b41452 TZ |
7241 | out: |
7242 | mutex_unlock(&trace_types_lock); | |
7243 | ||
7244 | return ret; | |
7245 | } | |
7246 | ||
6de58e62 SRRH |
7247 | struct ftrace_buffer_info { |
7248 | struct trace_iterator iter; | |
7249 | void *spare; | |
73a757e6 | 7250 | unsigned int spare_cpu; |
6de58e62 SRRH |
7251 | unsigned int read; |
7252 | }; | |
7253 | ||
debdd57f HT |
7254 | #ifdef CONFIG_TRACER_SNAPSHOT |
7255 | static int tracing_snapshot_open(struct inode *inode, struct file *file) | |
7256 | { | |
6484c71c | 7257 | struct trace_array *tr = inode->i_private; |
debdd57f | 7258 | struct trace_iterator *iter; |
2b6080f2 | 7259 | struct seq_file *m; |
8530dec6 | 7260 | int ret; |
debdd57f | 7261 | |
8530dec6 SRV |
7262 | ret = tracing_check_open_get_tr(tr); |
7263 | if (ret) | |
7264 | return ret; | |
ff451961 | 7265 | |
debdd57f | 7266 | if (file->f_mode & FMODE_READ) { |
6484c71c | 7267 | iter = __tracing_open(inode, file, true); |
debdd57f HT |
7268 | if (IS_ERR(iter)) |
7269 | ret = PTR_ERR(iter); | |
2b6080f2 SR |
7270 | } else { |
7271 | /* Writes still need the seq_file to hold the private data */ | |
f77d09a3 | 7272 | ret = -ENOMEM; |
2b6080f2 SR |
7273 | m = kzalloc(sizeof(*m), GFP_KERNEL); |
7274 | if (!m) | |
f77d09a3 | 7275 | goto out; |
2b6080f2 SR |
7276 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); |
7277 | if (!iter) { | |
7278 | kfree(m); | |
f77d09a3 | 7279 | goto out; |
2b6080f2 | 7280 | } |
f77d09a3 AL |
7281 | ret = 0; |
7282 | ||
ff451961 | 7283 | iter->tr = tr; |
1c5eb448 | 7284 | iter->array_buffer = &tr->max_buffer; |
6484c71c | 7285 | iter->cpu_file = tracing_get_cpu(inode); |
2b6080f2 SR |
7286 | m->private = iter; |
7287 | file->private_data = m; | |
debdd57f | 7288 | } |
f77d09a3 | 7289 | out: |
ff451961 SRRH |
7290 | if (ret < 0) |
7291 | trace_array_put(tr); | |
7292 | ||
debdd57f HT |
7293 | return ret; |
7294 | } | |
7295 | ||
7296 | static ssize_t | |
7297 | tracing_snapshot_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
7298 | loff_t *ppos) | |
7299 | { | |
2b6080f2 SR |
7300 | struct seq_file *m = filp->private_data; |
7301 | struct trace_iterator *iter = m->private; | |
7302 | struct trace_array *tr = iter->tr; | |
debdd57f HT |
7303 | unsigned long val; |
7304 | int ret; | |
7305 | ||
7306 | ret = tracing_update_buffers(); | |
7307 | if (ret < 0) | |
7308 | return ret; | |
7309 | ||
7310 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); | |
7311 | if (ret) | |
7312 | return ret; | |
7313 | ||
7314 | mutex_lock(&trace_types_lock); | |
7315 | ||
2b6080f2 | 7316 | if (tr->current_trace->use_max_tr) { |
debdd57f HT |
7317 | ret = -EBUSY; |
7318 | goto out; | |
7319 | } | |
7320 | ||
a35873a0 TZ |
7321 | arch_spin_lock(&tr->max_lock); |
7322 | if (tr->cond_snapshot) | |
7323 | ret = -EBUSY; | |
7324 | arch_spin_unlock(&tr->max_lock); | |
7325 | if (ret) | |
7326 | goto out; | |
7327 | ||
debdd57f HT |
7328 | switch (val) { |
7329 | case 0: | |
f1affcaa SRRH |
7330 | if (iter->cpu_file != RING_BUFFER_ALL_CPUS) { |
7331 | ret = -EINVAL; | |
7332 | break; | |
debdd57f | 7333 | } |
3209cff4 SRRH |
7334 | if (tr->allocated_snapshot) |
7335 | free_snapshot(tr); | |
debdd57f HT |
7336 | break; |
7337 | case 1: | |
f1affcaa SRRH |
7338 | /* Only allow per-cpu swap if the ring buffer supports it */ |
7339 | #ifndef CONFIG_RING_BUFFER_ALLOW_SWAP | |
7340 | if (iter->cpu_file != RING_BUFFER_ALL_CPUS) { | |
7341 | ret = -EINVAL; | |
7342 | break; | |
7343 | } | |
7344 | #endif | |
46cc0b44 ET |
7345 | if (tr->allocated_snapshot) |
7346 | ret = resize_buffer_duplicate_size(&tr->max_buffer, | |
1c5eb448 | 7347 | &tr->array_buffer, iter->cpu_file); |
46cc0b44 | 7348 | else |
2824f503 | 7349 | ret = tracing_alloc_snapshot_instance(tr); |
46cc0b44 ET |
7350 | if (ret < 0) |
7351 | break; | |
debdd57f HT |
7352 | local_irq_disable(); |
7353 | /* Now, we're going to swap */ | |
f1affcaa | 7354 | if (iter->cpu_file == RING_BUFFER_ALL_CPUS) |
a35873a0 | 7355 | update_max_tr(tr, current, smp_processor_id(), NULL); |
f1affcaa | 7356 | else |
ce9bae55 | 7357 | update_max_tr_single(tr, current, iter->cpu_file); |
debdd57f HT |
7358 | local_irq_enable(); |
7359 | break; | |
7360 | default: | |
45ad21ca | 7361 | if (tr->allocated_snapshot) { |
f1affcaa SRRH |
7362 | if (iter->cpu_file == RING_BUFFER_ALL_CPUS) |
7363 | tracing_reset_online_cpus(&tr->max_buffer); | |
7364 | else | |
a47b53e9 | 7365 | tracing_reset_cpu(&tr->max_buffer, iter->cpu_file); |
f1affcaa | 7366 | } |
debdd57f HT |
7367 | break; |
7368 | } | |
7369 | ||
7370 | if (ret >= 0) { | |
7371 | *ppos += cnt; | |
7372 | ret = cnt; | |
7373 | } | |
7374 | out: | |
7375 | mutex_unlock(&trace_types_lock); | |
7376 | return ret; | |
7377 | } | |
2b6080f2 SR |
7378 | |
7379 | static int tracing_snapshot_release(struct inode *inode, struct file *file) | |
7380 | { | |
7381 | struct seq_file *m = file->private_data; | |
ff451961 SRRH |
7382 | int ret; |
7383 | ||
7384 | ret = tracing_release(inode, file); | |
2b6080f2 SR |
7385 | |
7386 | if (file->f_mode & FMODE_READ) | |
ff451961 | 7387 | return ret; |
2b6080f2 SR |
7388 | |
7389 | /* If write only, the seq_file is just a stub */ | |
7390 | if (m) | |
7391 | kfree(m->private); | |
7392 | kfree(m); | |
7393 | ||
7394 | return 0; | |
7395 | } | |
7396 | ||
6de58e62 SRRH |
7397 | static int tracing_buffers_open(struct inode *inode, struct file *filp); |
7398 | static ssize_t tracing_buffers_read(struct file *filp, char __user *ubuf, | |
7399 | size_t count, loff_t *ppos); | |
7400 | static int tracing_buffers_release(struct inode *inode, struct file *file); | |
7401 | static ssize_t tracing_buffers_splice_read(struct file *file, loff_t *ppos, | |
7402 | struct pipe_inode_info *pipe, size_t len, unsigned int flags); | |
7403 | ||
7404 | static int snapshot_raw_open(struct inode *inode, struct file *filp) | |
7405 | { | |
7406 | struct ftrace_buffer_info *info; | |
7407 | int ret; | |
7408 | ||
17911ff3 | 7409 | /* The following checks for tracefs lockdown */ |
6de58e62 SRRH |
7410 | ret = tracing_buffers_open(inode, filp); |
7411 | if (ret < 0) | |
7412 | return ret; | |
7413 | ||
7414 | info = filp->private_data; | |
7415 | ||
7416 | if (info->iter.trace->use_max_tr) { | |
7417 | tracing_buffers_release(inode, filp); | |
7418 | return -EBUSY; | |
7419 | } | |
7420 | ||
7421 | info->iter.snapshot = true; | |
1c5eb448 | 7422 | info->iter.array_buffer = &info->iter.tr->max_buffer; |
6de58e62 SRRH |
7423 | |
7424 | return ret; | |
7425 | } | |
7426 | ||
debdd57f HT |
7427 | #endif /* CONFIG_TRACER_SNAPSHOT */ |
7428 | ||
7429 | ||
6508fa76 SF |
7430 | static const struct file_operations tracing_thresh_fops = { |
7431 | .open = tracing_open_generic, | |
7432 | .read = tracing_thresh_read, | |
7433 | .write = tracing_thresh_write, | |
7434 | .llseek = generic_file_llseek, | |
7435 | }; | |
7436 | ||
f971cc9a | 7437 | #if defined(CONFIG_TRACER_MAX_TRACE) || defined(CONFIG_HWLAT_TRACER) |
5e2336a0 | 7438 | static const struct file_operations tracing_max_lat_fops = { |
4bf39a94 IM |
7439 | .open = tracing_open_generic, |
7440 | .read = tracing_max_lat_read, | |
7441 | .write = tracing_max_lat_write, | |
b444786f | 7442 | .llseek = generic_file_llseek, |
bc0c38d1 | 7443 | }; |
e428abbb | 7444 | #endif |
bc0c38d1 | 7445 | |
5e2336a0 | 7446 | static const struct file_operations set_tracer_fops = { |
4bf39a94 IM |
7447 | .open = tracing_open_generic, |
7448 | .read = tracing_set_trace_read, | |
7449 | .write = tracing_set_trace_write, | |
b444786f | 7450 | .llseek = generic_file_llseek, |
bc0c38d1 SR |
7451 | }; |
7452 | ||
5e2336a0 | 7453 | static const struct file_operations tracing_pipe_fops = { |
4bf39a94 | 7454 | .open = tracing_open_pipe, |
2a2cc8f7 | 7455 | .poll = tracing_poll_pipe, |
4bf39a94 | 7456 | .read = tracing_read_pipe, |
3c56819b | 7457 | .splice_read = tracing_splice_read_pipe, |
4bf39a94 | 7458 | .release = tracing_release_pipe, |
b444786f | 7459 | .llseek = no_llseek, |
b3806b43 SR |
7460 | }; |
7461 | ||
5e2336a0 | 7462 | static const struct file_operations tracing_entries_fops = { |
0bc392ee | 7463 | .open = tracing_open_generic_tr, |
a98a3c3f SR |
7464 | .read = tracing_entries_read, |
7465 | .write = tracing_entries_write, | |
b444786f | 7466 | .llseek = generic_file_llseek, |
0bc392ee | 7467 | .release = tracing_release_generic_tr, |
a98a3c3f SR |
7468 | }; |
7469 | ||
f81ab074 | 7470 | static const struct file_operations tracing_total_entries_fops = { |
7b85af63 | 7471 | .open = tracing_open_generic_tr, |
f81ab074 VN |
7472 | .read = tracing_total_entries_read, |
7473 | .llseek = generic_file_llseek, | |
7b85af63 | 7474 | .release = tracing_release_generic_tr, |
f81ab074 VN |
7475 | }; |
7476 | ||
4f271a2a | 7477 | static const struct file_operations tracing_free_buffer_fops = { |
7b85af63 | 7478 | .open = tracing_open_generic_tr, |
4f271a2a VN |
7479 | .write = tracing_free_buffer_write, |
7480 | .release = tracing_free_buffer_release, | |
7481 | }; | |
7482 | ||
5e2336a0 | 7483 | static const struct file_operations tracing_mark_fops = { |
7b85af63 | 7484 | .open = tracing_open_generic_tr, |
5bf9a1ee | 7485 | .write = tracing_mark_write, |
b444786f | 7486 | .llseek = generic_file_llseek, |
7b85af63 | 7487 | .release = tracing_release_generic_tr, |
5bf9a1ee PP |
7488 | }; |
7489 | ||
fa32e855 SR |
7490 | static const struct file_operations tracing_mark_raw_fops = { |
7491 | .open = tracing_open_generic_tr, | |
7492 | .write = tracing_mark_raw_write, | |
7493 | .llseek = generic_file_llseek, | |
7494 | .release = tracing_release_generic_tr, | |
7495 | }; | |
7496 | ||
5079f326 | 7497 | static const struct file_operations trace_clock_fops = { |
13f16d20 LZ |
7498 | .open = tracing_clock_open, |
7499 | .read = seq_read, | |
7500 | .llseek = seq_lseek, | |
7b85af63 | 7501 | .release = tracing_single_release_tr, |
5079f326 Z |
7502 | .write = tracing_clock_write, |
7503 | }; | |
7504 | ||
2c1ea60b TZ |
7505 | static const struct file_operations trace_time_stamp_mode_fops = { |
7506 | .open = tracing_time_stamp_mode_open, | |
7507 | .read = seq_read, | |
7508 | .llseek = seq_lseek, | |
7509 | .release = tracing_single_release_tr, | |
7510 | }; | |
7511 | ||
debdd57f HT |
7512 | #ifdef CONFIG_TRACER_SNAPSHOT |
7513 | static const struct file_operations snapshot_fops = { | |
7514 | .open = tracing_snapshot_open, | |
7515 | .read = seq_read, | |
7516 | .write = tracing_snapshot_write, | |
098c879e | 7517 | .llseek = tracing_lseek, |
2b6080f2 | 7518 | .release = tracing_snapshot_release, |
debdd57f | 7519 | }; |
debdd57f | 7520 | |
6de58e62 SRRH |
7521 | static const struct file_operations snapshot_raw_fops = { |
7522 | .open = snapshot_raw_open, | |
7523 | .read = tracing_buffers_read, | |
7524 | .release = tracing_buffers_release, | |
7525 | .splice_read = tracing_buffers_splice_read, | |
7526 | .llseek = no_llseek, | |
2cadf913 SR |
7527 | }; |
7528 | ||
6de58e62 SRRH |
7529 | #endif /* CONFIG_TRACER_SNAPSHOT */ |
7530 | ||
8a062902 TZ |
7531 | #define TRACING_LOG_ERRS_MAX 8 |
7532 | #define TRACING_LOG_LOC_MAX 128 | |
7533 | ||
7534 | #define CMD_PREFIX " Command: " | |
7535 | ||
7536 | struct err_info { | |
7537 | const char **errs; /* ptr to loc-specific array of err strings */ | |
7538 | u8 type; /* index into errs -> specific err string */ | |
7539 | u8 pos; /* MAX_FILTER_STR_VAL = 256 */ | |
7540 | u64 ts; | |
7541 | }; | |
7542 | ||
7543 | struct tracing_log_err { | |
7544 | struct list_head list; | |
7545 | struct err_info info; | |
7546 | char loc[TRACING_LOG_LOC_MAX]; /* err location */ | |
7547 | char cmd[MAX_FILTER_STR_VAL]; /* what caused err */ | |
7548 | }; | |
7549 | ||
8a062902 TZ |
7550 | static DEFINE_MUTEX(tracing_err_log_lock); |
7551 | ||
ff585c5b | 7552 | static struct tracing_log_err *get_tracing_log_err(struct trace_array *tr) |
8a062902 TZ |
7553 | { |
7554 | struct tracing_log_err *err; | |
7555 | ||
2f754e77 | 7556 | if (tr->n_err_log_entries < TRACING_LOG_ERRS_MAX) { |
8a062902 TZ |
7557 | err = kzalloc(sizeof(*err), GFP_KERNEL); |
7558 | if (!err) | |
7559 | err = ERR_PTR(-ENOMEM); | |
2f754e77 | 7560 | tr->n_err_log_entries++; |
8a062902 TZ |
7561 | |
7562 | return err; | |
7563 | } | |
7564 | ||
2f754e77 | 7565 | err = list_first_entry(&tr->err_log, struct tracing_log_err, list); |
8a062902 TZ |
7566 | list_del(&err->list); |
7567 | ||
7568 | return err; | |
7569 | } | |
7570 | ||
7571 | /** | |
7572 | * err_pos - find the position of a string within a command for error careting | |
7573 | * @cmd: The tracing command that caused the error | |
7574 | * @str: The string to position the caret at within @cmd | |
7575 | * | |
f2cc020d | 7576 | * Finds the position of the first occurrence of @str within @cmd. The |
8a062902 TZ |
7577 | * return value can be passed to tracing_log_err() for caret placement |
7578 | * within @cmd. | |
7579 | * | |
f2cc020d | 7580 | * Returns the index within @cmd of the first occurrence of @str or 0 |
8a062902 TZ |
7581 | * if @str was not found. |
7582 | */ | |
7583 | unsigned int err_pos(char *cmd, const char *str) | |
7584 | { | |
7585 | char *found; | |
7586 | ||
7587 | if (WARN_ON(!strlen(cmd))) | |
7588 | return 0; | |
7589 | ||
7590 | found = strstr(cmd, str); | |
7591 | if (found) | |
7592 | return found - cmd; | |
7593 | ||
7594 | return 0; | |
7595 | } | |
7596 | ||
7597 | /** | |
7598 | * tracing_log_err - write an error to the tracing error log | |
2f754e77 | 7599 | * @tr: The associated trace array for the error (NULL for top level array) |
8a062902 TZ |
7600 | * @loc: A string describing where the error occurred |
7601 | * @cmd: The tracing command that caused the error | |
7602 | * @errs: The array of loc-specific static error strings | |
7603 | * @type: The index into errs[], which produces the specific static err string | |
7604 | * @pos: The position the caret should be placed in the cmd | |
7605 | * | |
7606 | * Writes an error into tracing/error_log of the form: | |
7607 | * | |
7608 | * <loc>: error: <text> | |
7609 | * Command: <cmd> | |
7610 | * ^ | |
7611 | * | |
7612 | * tracing/error_log is a small log file containing the last | |
7613 | * TRACING_LOG_ERRS_MAX errors (8). Memory for errors isn't allocated | |
7614 | * unless there has been a tracing error, and the error log can be | |
7615 | * cleared and have its memory freed by writing the empty string in | |
7616 | * truncation mode to it i.e. echo > tracing/error_log. | |
7617 | * | |
7618 | * NOTE: the @errs array along with the @type param are used to | |
7619 | * produce a static error string - this string is not copied and saved | |
7620 | * when the error is logged - only a pointer to it is saved. See | |
7621 | * existing callers for examples of how static strings are typically | |
7622 | * defined for use with tracing_log_err(). | |
7623 | */ | |
2f754e77 SRV |
7624 | void tracing_log_err(struct trace_array *tr, |
7625 | const char *loc, const char *cmd, | |
8a062902 TZ |
7626 | const char **errs, u8 type, u8 pos) |
7627 | { | |
7628 | struct tracing_log_err *err; | |
7629 | ||
2f754e77 SRV |
7630 | if (!tr) |
7631 | tr = &global_trace; | |
7632 | ||
8a062902 | 7633 | mutex_lock(&tracing_err_log_lock); |
2f754e77 | 7634 | err = get_tracing_log_err(tr); |
8a062902 TZ |
7635 | if (PTR_ERR(err) == -ENOMEM) { |
7636 | mutex_unlock(&tracing_err_log_lock); | |
7637 | return; | |
7638 | } | |
7639 | ||
7640 | snprintf(err->loc, TRACING_LOG_LOC_MAX, "%s: error: ", loc); | |
7641 | snprintf(err->cmd, MAX_FILTER_STR_VAL,"\n" CMD_PREFIX "%s\n", cmd); | |
7642 | ||
7643 | err->info.errs = errs; | |
7644 | err->info.type = type; | |
7645 | err->info.pos = pos; | |
7646 | err->info.ts = local_clock(); | |
7647 | ||
2f754e77 | 7648 | list_add_tail(&err->list, &tr->err_log); |
8a062902 TZ |
7649 | mutex_unlock(&tracing_err_log_lock); |
7650 | } | |
7651 | ||
2f754e77 | 7652 | static void clear_tracing_err_log(struct trace_array *tr) |
8a062902 TZ |
7653 | { |
7654 | struct tracing_log_err *err, *next; | |
7655 | ||
7656 | mutex_lock(&tracing_err_log_lock); | |
2f754e77 | 7657 | list_for_each_entry_safe(err, next, &tr->err_log, list) { |
8a062902 TZ |
7658 | list_del(&err->list); |
7659 | kfree(err); | |
7660 | } | |
7661 | ||
2f754e77 | 7662 | tr->n_err_log_entries = 0; |
8a062902 TZ |
7663 | mutex_unlock(&tracing_err_log_lock); |
7664 | } | |
7665 | ||
7666 | static void *tracing_err_log_seq_start(struct seq_file *m, loff_t *pos) | |
7667 | { | |
2f754e77 SRV |
7668 | struct trace_array *tr = m->private; |
7669 | ||
8a062902 TZ |
7670 | mutex_lock(&tracing_err_log_lock); |
7671 | ||
2f754e77 | 7672 | return seq_list_start(&tr->err_log, *pos); |
8a062902 TZ |
7673 | } |
7674 | ||
7675 | static void *tracing_err_log_seq_next(struct seq_file *m, void *v, loff_t *pos) | |
7676 | { | |
2f754e77 SRV |
7677 | struct trace_array *tr = m->private; |
7678 | ||
7679 | return seq_list_next(v, &tr->err_log, pos); | |
8a062902 TZ |
7680 | } |
7681 | ||
7682 | static void tracing_err_log_seq_stop(struct seq_file *m, void *v) | |
7683 | { | |
7684 | mutex_unlock(&tracing_err_log_lock); | |
7685 | } | |
7686 | ||
7687 | static void tracing_err_log_show_pos(struct seq_file *m, u8 pos) | |
7688 | { | |
7689 | u8 i; | |
7690 | ||
7691 | for (i = 0; i < sizeof(CMD_PREFIX) - 1; i++) | |
7692 | seq_putc(m, ' '); | |
7693 | for (i = 0; i < pos; i++) | |
7694 | seq_putc(m, ' '); | |
7695 | seq_puts(m, "^\n"); | |
7696 | } | |
7697 | ||
7698 | static int tracing_err_log_seq_show(struct seq_file *m, void *v) | |
7699 | { | |
7700 | struct tracing_log_err *err = v; | |
7701 | ||
7702 | if (err) { | |
7703 | const char *err_text = err->info.errs[err->info.type]; | |
7704 | u64 sec = err->info.ts; | |
7705 | u32 nsec; | |
7706 | ||
7707 | nsec = do_div(sec, NSEC_PER_SEC); | |
7708 | seq_printf(m, "[%5llu.%06u] %s%s", sec, nsec / 1000, | |
7709 | err->loc, err_text); | |
7710 | seq_printf(m, "%s", err->cmd); | |
7711 | tracing_err_log_show_pos(m, err->info.pos); | |
7712 | } | |
7713 | ||
7714 | return 0; | |
7715 | } | |
7716 | ||
7717 | static const struct seq_operations tracing_err_log_seq_ops = { | |
7718 | .start = tracing_err_log_seq_start, | |
7719 | .next = tracing_err_log_seq_next, | |
7720 | .stop = tracing_err_log_seq_stop, | |
7721 | .show = tracing_err_log_seq_show | |
7722 | }; | |
7723 | ||
7724 | static int tracing_err_log_open(struct inode *inode, struct file *file) | |
7725 | { | |
2f754e77 | 7726 | struct trace_array *tr = inode->i_private; |
8a062902 TZ |
7727 | int ret = 0; |
7728 | ||
8530dec6 SRV |
7729 | ret = tracing_check_open_get_tr(tr); |
7730 | if (ret) | |
7731 | return ret; | |
2f754e77 | 7732 | |
8a062902 TZ |
7733 | /* If this file was opened for write, then erase contents */ |
7734 | if ((file->f_mode & FMODE_WRITE) && (file->f_flags & O_TRUNC)) | |
2f754e77 | 7735 | clear_tracing_err_log(tr); |
8a062902 | 7736 | |
2f754e77 | 7737 | if (file->f_mode & FMODE_READ) { |
8a062902 | 7738 | ret = seq_open(file, &tracing_err_log_seq_ops); |
2f754e77 SRV |
7739 | if (!ret) { |
7740 | struct seq_file *m = file->private_data; | |
7741 | m->private = tr; | |
7742 | } else { | |
7743 | trace_array_put(tr); | |
7744 | } | |
7745 | } | |
8a062902 TZ |
7746 | return ret; |
7747 | } | |
7748 | ||
7749 | static ssize_t tracing_err_log_write(struct file *file, | |
7750 | const char __user *buffer, | |
7751 | size_t count, loff_t *ppos) | |
7752 | { | |
7753 | return count; | |
7754 | } | |
7755 | ||
d122ed62 TM |
7756 | static int tracing_err_log_release(struct inode *inode, struct file *file) |
7757 | { | |
7758 | struct trace_array *tr = inode->i_private; | |
7759 | ||
7760 | trace_array_put(tr); | |
7761 | ||
7762 | if (file->f_mode & FMODE_READ) | |
7763 | seq_release(inode, file); | |
7764 | ||
7765 | return 0; | |
7766 | } | |
7767 | ||
8a062902 TZ |
7768 | static const struct file_operations tracing_err_log_fops = { |
7769 | .open = tracing_err_log_open, | |
7770 | .write = tracing_err_log_write, | |
7771 | .read = seq_read, | |
7772 | .llseek = seq_lseek, | |
d122ed62 | 7773 | .release = tracing_err_log_release, |
8a062902 TZ |
7774 | }; |
7775 | ||
2cadf913 SR |
7776 | static int tracing_buffers_open(struct inode *inode, struct file *filp) |
7777 | { | |
46ef2be0 | 7778 | struct trace_array *tr = inode->i_private; |
2cadf913 | 7779 | struct ftrace_buffer_info *info; |
7b85af63 | 7780 | int ret; |
2cadf913 | 7781 | |
8530dec6 SRV |
7782 | ret = tracing_check_open_get_tr(tr); |
7783 | if (ret) | |
7784 | return ret; | |
7b85af63 | 7785 | |
0f69dae4 | 7786 | info = kvzalloc(sizeof(*info), GFP_KERNEL); |
7b85af63 SRRH |
7787 | if (!info) { |
7788 | trace_array_put(tr); | |
2cadf913 | 7789 | return -ENOMEM; |
7b85af63 | 7790 | } |
2cadf913 | 7791 | |
a695cb58 SRRH |
7792 | mutex_lock(&trace_types_lock); |
7793 | ||
cc60cdc9 | 7794 | info->iter.tr = tr; |
46ef2be0 | 7795 | info->iter.cpu_file = tracing_get_cpu(inode); |
b627344f | 7796 | info->iter.trace = tr->current_trace; |
1c5eb448 | 7797 | info->iter.array_buffer = &tr->array_buffer; |
cc60cdc9 | 7798 | info->spare = NULL; |
2cadf913 | 7799 | /* Force reading ring buffer for first read */ |
cc60cdc9 | 7800 | info->read = (unsigned int)-1; |
2cadf913 SR |
7801 | |
7802 | filp->private_data = info; | |
7803 | ||
7ef282e0 | 7804 | tr->trace_ref++; |
cf6ab6d9 | 7805 | |
a695cb58 SRRH |
7806 | mutex_unlock(&trace_types_lock); |
7807 | ||
7b85af63 SRRH |
7808 | ret = nonseekable_open(inode, filp); |
7809 | if (ret < 0) | |
7810 | trace_array_put(tr); | |
7811 | ||
7812 | return ret; | |
2cadf913 SR |
7813 | } |
7814 | ||
9dd95748 | 7815 | static __poll_t |
cc60cdc9 SR |
7816 | tracing_buffers_poll(struct file *filp, poll_table *poll_table) |
7817 | { | |
7818 | struct ftrace_buffer_info *info = filp->private_data; | |
7819 | struct trace_iterator *iter = &info->iter; | |
7820 | ||
7821 | return trace_poll(iter, filp, poll_table); | |
7822 | } | |
7823 | ||
2cadf913 SR |
7824 | static ssize_t |
7825 | tracing_buffers_read(struct file *filp, char __user *ubuf, | |
7826 | size_t count, loff_t *ppos) | |
7827 | { | |
7828 | struct ftrace_buffer_info *info = filp->private_data; | |
cc60cdc9 | 7829 | struct trace_iterator *iter = &info->iter; |
a7e52ad7 | 7830 | ssize_t ret = 0; |
6de58e62 | 7831 | ssize_t size; |
2cadf913 | 7832 | |
2dc5d12b SR |
7833 | if (!count) |
7834 | return 0; | |
7835 | ||
6de58e62 | 7836 | #ifdef CONFIG_TRACER_MAX_TRACE |
d716ff71 SRRH |
7837 | if (iter->snapshot && iter->tr->current_trace->use_max_tr) |
7838 | return -EBUSY; | |
6de58e62 SRRH |
7839 | #endif |
7840 | ||
73a757e6 | 7841 | if (!info->spare) { |
1c5eb448 | 7842 | info->spare = ring_buffer_alloc_read_page(iter->array_buffer->buffer, |
12883efb | 7843 | iter->cpu_file); |
a7e52ad7 SRV |
7844 | if (IS_ERR(info->spare)) { |
7845 | ret = PTR_ERR(info->spare); | |
7846 | info->spare = NULL; | |
7847 | } else { | |
7848 | info->spare_cpu = iter->cpu_file; | |
7849 | } | |
73a757e6 | 7850 | } |
ddd538f3 | 7851 | if (!info->spare) |
a7e52ad7 | 7852 | return ret; |
ddd538f3 | 7853 | |
2cadf913 SR |
7854 | /* Do we have previous read data to read? */ |
7855 | if (info->read < PAGE_SIZE) | |
7856 | goto read; | |
7857 | ||
b627344f | 7858 | again: |
cc60cdc9 | 7859 | trace_access_lock(iter->cpu_file); |
1c5eb448 | 7860 | ret = ring_buffer_read_page(iter->array_buffer->buffer, |
2cadf913 SR |
7861 | &info->spare, |
7862 | count, | |
cc60cdc9 SR |
7863 | iter->cpu_file, 0); |
7864 | trace_access_unlock(iter->cpu_file); | |
2cadf913 | 7865 | |
b627344f SR |
7866 | if (ret < 0) { |
7867 | if (trace_empty(iter)) { | |
d716ff71 SRRH |
7868 | if ((filp->f_flags & O_NONBLOCK)) |
7869 | return -EAGAIN; | |
7870 | ||
2c2b0a78 | 7871 | ret = wait_on_pipe(iter, 0); |
d716ff71 SRRH |
7872 | if (ret) |
7873 | return ret; | |
7874 | ||
b627344f SR |
7875 | goto again; |
7876 | } | |
d716ff71 | 7877 | return 0; |
b627344f | 7878 | } |
436fc280 | 7879 | |
436fc280 | 7880 | info->read = 0; |
b627344f | 7881 | read: |
2cadf913 SR |
7882 | size = PAGE_SIZE - info->read; |
7883 | if (size > count) | |
7884 | size = count; | |
7885 | ||
7886 | ret = copy_to_user(ubuf, info->spare + info->read, size); | |
d716ff71 SRRH |
7887 | if (ret == size) |
7888 | return -EFAULT; | |
7889 | ||
2dc5d12b SR |
7890 | size -= ret; |
7891 | ||
2cadf913 SR |
7892 | *ppos += size; |
7893 | info->read += size; | |
7894 | ||
7895 | return size; | |
7896 | } | |
7897 | ||
7898 | static int tracing_buffers_release(struct inode *inode, struct file *file) | |
7899 | { | |
7900 | struct ftrace_buffer_info *info = file->private_data; | |
cc60cdc9 | 7901 | struct trace_iterator *iter = &info->iter; |
2cadf913 | 7902 | |
a695cb58 SRRH |
7903 | mutex_lock(&trace_types_lock); |
7904 | ||
7ef282e0 | 7905 | iter->tr->trace_ref--; |
cf6ab6d9 | 7906 | |
ff451961 | 7907 | __trace_array_put(iter->tr); |
2cadf913 | 7908 | |
ddd538f3 | 7909 | if (info->spare) |
1c5eb448 | 7910 | ring_buffer_free_read_page(iter->array_buffer->buffer, |
73a757e6 | 7911 | info->spare_cpu, info->spare); |
0f69dae4 | 7912 | kvfree(info); |
2cadf913 | 7913 | |
a695cb58 SRRH |
7914 | mutex_unlock(&trace_types_lock); |
7915 | ||
2cadf913 SR |
7916 | return 0; |
7917 | } | |
7918 | ||
7919 | struct buffer_ref { | |
13292494 | 7920 | struct trace_buffer *buffer; |
2cadf913 | 7921 | void *page; |
73a757e6 | 7922 | int cpu; |
b9872226 | 7923 | refcount_t refcount; |
2cadf913 SR |
7924 | }; |
7925 | ||
b9872226 JH |
7926 | static void buffer_ref_release(struct buffer_ref *ref) |
7927 | { | |
7928 | if (!refcount_dec_and_test(&ref->refcount)) | |
7929 | return; | |
7930 | ring_buffer_free_read_page(ref->buffer, ref->cpu, ref->page); | |
7931 | kfree(ref); | |
7932 | } | |
7933 | ||
2cadf913 SR |
7934 | static void buffer_pipe_buf_release(struct pipe_inode_info *pipe, |
7935 | struct pipe_buffer *buf) | |
7936 | { | |
7937 | struct buffer_ref *ref = (struct buffer_ref *)buf->private; | |
7938 | ||
b9872226 | 7939 | buffer_ref_release(ref); |
2cadf913 SR |
7940 | buf->private = 0; |
7941 | } | |
7942 | ||
15fab63e | 7943 | static bool buffer_pipe_buf_get(struct pipe_inode_info *pipe, |
2cadf913 SR |
7944 | struct pipe_buffer *buf) |
7945 | { | |
7946 | struct buffer_ref *ref = (struct buffer_ref *)buf->private; | |
7947 | ||
e9e1a2e7 | 7948 | if (refcount_read(&ref->refcount) > INT_MAX/2) |
15fab63e MW |
7949 | return false; |
7950 | ||
b9872226 | 7951 | refcount_inc(&ref->refcount); |
15fab63e | 7952 | return true; |
2cadf913 SR |
7953 | } |
7954 | ||
7955 | /* Pipe buffer operations for a buffer. */ | |
28dfef8f | 7956 | static const struct pipe_buf_operations buffer_pipe_buf_ops = { |
2cadf913 | 7957 | .release = buffer_pipe_buf_release, |
2cadf913 SR |
7958 | .get = buffer_pipe_buf_get, |
7959 | }; | |
7960 | ||
7961 | /* | |
7962 | * Callback from splice_to_pipe(), if we need to release some pages | |
7963 | * at the end of the spd in case we error'ed out in filling the pipe. | |
7964 | */ | |
7965 | static void buffer_spd_release(struct splice_pipe_desc *spd, unsigned int i) | |
7966 | { | |
7967 | struct buffer_ref *ref = | |
7968 | (struct buffer_ref *)spd->partial[i].private; | |
7969 | ||
b9872226 | 7970 | buffer_ref_release(ref); |
2cadf913 SR |
7971 | spd->partial[i].private = 0; |
7972 | } | |
7973 | ||
7974 | static ssize_t | |
7975 | tracing_buffers_splice_read(struct file *file, loff_t *ppos, | |
7976 | struct pipe_inode_info *pipe, size_t len, | |
7977 | unsigned int flags) | |
7978 | { | |
7979 | struct ftrace_buffer_info *info = file->private_data; | |
cc60cdc9 | 7980 | struct trace_iterator *iter = &info->iter; |
35f3d14d JA |
7981 | struct partial_page partial_def[PIPE_DEF_BUFFERS]; |
7982 | struct page *pages_def[PIPE_DEF_BUFFERS]; | |
2cadf913 | 7983 | struct splice_pipe_desc spd = { |
35f3d14d JA |
7984 | .pages = pages_def, |
7985 | .partial = partial_def, | |
047fe360 | 7986 | .nr_pages_max = PIPE_DEF_BUFFERS, |
2cadf913 SR |
7987 | .ops = &buffer_pipe_buf_ops, |
7988 | .spd_release = buffer_spd_release, | |
7989 | }; | |
7990 | struct buffer_ref *ref; | |
6b7e633f | 7991 | int entries, i; |
07906da7 | 7992 | ssize_t ret = 0; |
2cadf913 | 7993 | |
6de58e62 | 7994 | #ifdef CONFIG_TRACER_MAX_TRACE |
d716ff71 SRRH |
7995 | if (iter->snapshot && iter->tr->current_trace->use_max_tr) |
7996 | return -EBUSY; | |
6de58e62 SRRH |
7997 | #endif |
7998 | ||
d716ff71 SRRH |
7999 | if (*ppos & (PAGE_SIZE - 1)) |
8000 | return -EINVAL; | |
93cfb3c9 LJ |
8001 | |
8002 | if (len & (PAGE_SIZE - 1)) { | |
d716ff71 SRRH |
8003 | if (len < PAGE_SIZE) |
8004 | return -EINVAL; | |
93cfb3c9 LJ |
8005 | len &= PAGE_MASK; |
8006 | } | |
8007 | ||
1ae2293d AV |
8008 | if (splice_grow_spd(pipe, &spd)) |
8009 | return -ENOMEM; | |
8010 | ||
cc60cdc9 SR |
8011 | again: |
8012 | trace_access_lock(iter->cpu_file); | |
1c5eb448 | 8013 | entries = ring_buffer_entries_cpu(iter->array_buffer->buffer, iter->cpu_file); |
93459c6c | 8014 | |
a786c06d | 8015 | for (i = 0; i < spd.nr_pages_max && len && entries; i++, len -= PAGE_SIZE) { |
2cadf913 SR |
8016 | struct page *page; |
8017 | int r; | |
8018 | ||
8019 | ref = kzalloc(sizeof(*ref), GFP_KERNEL); | |
07906da7 RV |
8020 | if (!ref) { |
8021 | ret = -ENOMEM; | |
2cadf913 | 8022 | break; |
07906da7 | 8023 | } |
2cadf913 | 8024 | |
b9872226 | 8025 | refcount_set(&ref->refcount, 1); |
1c5eb448 | 8026 | ref->buffer = iter->array_buffer->buffer; |
cc60cdc9 | 8027 | ref->page = ring_buffer_alloc_read_page(ref->buffer, iter->cpu_file); |
a7e52ad7 SRV |
8028 | if (IS_ERR(ref->page)) { |
8029 | ret = PTR_ERR(ref->page); | |
8030 | ref->page = NULL; | |
2cadf913 SR |
8031 | kfree(ref); |
8032 | break; | |
8033 | } | |
73a757e6 | 8034 | ref->cpu = iter->cpu_file; |
2cadf913 SR |
8035 | |
8036 | r = ring_buffer_read_page(ref->buffer, &ref->page, | |
cc60cdc9 | 8037 | len, iter->cpu_file, 1); |
2cadf913 | 8038 | if (r < 0) { |
73a757e6 SRV |
8039 | ring_buffer_free_read_page(ref->buffer, ref->cpu, |
8040 | ref->page); | |
2cadf913 SR |
8041 | kfree(ref); |
8042 | break; | |
8043 | } | |
8044 | ||
2cadf913 SR |
8045 | page = virt_to_page(ref->page); |
8046 | ||
8047 | spd.pages[i] = page; | |
8048 | spd.partial[i].len = PAGE_SIZE; | |
8049 | spd.partial[i].offset = 0; | |
8050 | spd.partial[i].private = (unsigned long)ref; | |
8051 | spd.nr_pages++; | |
93cfb3c9 | 8052 | *ppos += PAGE_SIZE; |
93459c6c | 8053 | |
1c5eb448 | 8054 | entries = ring_buffer_entries_cpu(iter->array_buffer->buffer, iter->cpu_file); |
2cadf913 SR |
8055 | } |
8056 | ||
cc60cdc9 | 8057 | trace_access_unlock(iter->cpu_file); |
2cadf913 SR |
8058 | spd.nr_pages = i; |
8059 | ||
8060 | /* did we read anything? */ | |
8061 | if (!spd.nr_pages) { | |
07906da7 | 8062 | if (ret) |
1ae2293d | 8063 | goto out; |
d716ff71 | 8064 | |
1ae2293d | 8065 | ret = -EAGAIN; |
d716ff71 | 8066 | if ((file->f_flags & O_NONBLOCK) || (flags & SPLICE_F_NONBLOCK)) |
1ae2293d | 8067 | goto out; |
07906da7 | 8068 | |
03329f99 | 8069 | ret = wait_on_pipe(iter, iter->tr->buffer_percent); |
8b8b3683 | 8070 | if (ret) |
1ae2293d | 8071 | goto out; |
e30f53aa | 8072 | |
cc60cdc9 | 8073 | goto again; |
2cadf913 SR |
8074 | } |
8075 | ||
8076 | ret = splice_to_pipe(pipe, &spd); | |
1ae2293d | 8077 | out: |
047fe360 | 8078 | splice_shrink_spd(&spd); |
6de58e62 | 8079 | |
2cadf913 SR |
8080 | return ret; |
8081 | } | |
8082 | ||
8083 | static const struct file_operations tracing_buffers_fops = { | |
8084 | .open = tracing_buffers_open, | |
8085 | .read = tracing_buffers_read, | |
cc60cdc9 | 8086 | .poll = tracing_buffers_poll, |
2cadf913 SR |
8087 | .release = tracing_buffers_release, |
8088 | .splice_read = tracing_buffers_splice_read, | |
8089 | .llseek = no_llseek, | |
8090 | }; | |
8091 | ||
c8d77183 SR |
8092 | static ssize_t |
8093 | tracing_stats_read(struct file *filp, char __user *ubuf, | |
8094 | size_t count, loff_t *ppos) | |
8095 | { | |
4d3435b8 ON |
8096 | struct inode *inode = file_inode(filp); |
8097 | struct trace_array *tr = inode->i_private; | |
1c5eb448 | 8098 | struct array_buffer *trace_buf = &tr->array_buffer; |
4d3435b8 | 8099 | int cpu = tracing_get_cpu(inode); |
c8d77183 SR |
8100 | struct trace_seq *s; |
8101 | unsigned long cnt; | |
c64e148a VN |
8102 | unsigned long long t; |
8103 | unsigned long usec_rem; | |
c8d77183 | 8104 | |
e4f2d10f | 8105 | s = kmalloc(sizeof(*s), GFP_KERNEL); |
c8d77183 | 8106 | if (!s) |
a646365c | 8107 | return -ENOMEM; |
c8d77183 SR |
8108 | |
8109 | trace_seq_init(s); | |
8110 | ||
12883efb | 8111 | cnt = ring_buffer_entries_cpu(trace_buf->buffer, cpu); |
c8d77183 SR |
8112 | trace_seq_printf(s, "entries: %ld\n", cnt); |
8113 | ||
12883efb | 8114 | cnt = ring_buffer_overrun_cpu(trace_buf->buffer, cpu); |
c8d77183 SR |
8115 | trace_seq_printf(s, "overrun: %ld\n", cnt); |
8116 | ||
12883efb | 8117 | cnt = ring_buffer_commit_overrun_cpu(trace_buf->buffer, cpu); |
c8d77183 SR |
8118 | trace_seq_printf(s, "commit overrun: %ld\n", cnt); |
8119 | ||
12883efb | 8120 | cnt = ring_buffer_bytes_cpu(trace_buf->buffer, cpu); |
c64e148a VN |
8121 | trace_seq_printf(s, "bytes: %ld\n", cnt); |
8122 | ||
58e8eedf | 8123 | if (trace_clocks[tr->clock_id].in_ns) { |
11043d8b | 8124 | /* local or global for trace_clock */ |
12883efb | 8125 | t = ns2usecs(ring_buffer_oldest_event_ts(trace_buf->buffer, cpu)); |
11043d8b YY |
8126 | usec_rem = do_div(t, USEC_PER_SEC); |
8127 | trace_seq_printf(s, "oldest event ts: %5llu.%06lu\n", | |
8128 | t, usec_rem); | |
8129 | ||
f3ef7202 | 8130 | t = ns2usecs(ring_buffer_time_stamp(trace_buf->buffer)); |
11043d8b YY |
8131 | usec_rem = do_div(t, USEC_PER_SEC); |
8132 | trace_seq_printf(s, "now ts: %5llu.%06lu\n", t, usec_rem); | |
8133 | } else { | |
8134 | /* counter or tsc mode for trace_clock */ | |
8135 | trace_seq_printf(s, "oldest event ts: %llu\n", | |
12883efb | 8136 | ring_buffer_oldest_event_ts(trace_buf->buffer, cpu)); |
c64e148a | 8137 | |
11043d8b | 8138 | trace_seq_printf(s, "now ts: %llu\n", |
f3ef7202 | 8139 | ring_buffer_time_stamp(trace_buf->buffer)); |
11043d8b | 8140 | } |
c64e148a | 8141 | |
12883efb | 8142 | cnt = ring_buffer_dropped_events_cpu(trace_buf->buffer, cpu); |
884bfe89 SP |
8143 | trace_seq_printf(s, "dropped events: %ld\n", cnt); |
8144 | ||
12883efb | 8145 | cnt = ring_buffer_read_events_cpu(trace_buf->buffer, cpu); |
ad964704 SRRH |
8146 | trace_seq_printf(s, "read events: %ld\n", cnt); |
8147 | ||
5ac48378 SRRH |
8148 | count = simple_read_from_buffer(ubuf, count, ppos, |
8149 | s->buffer, trace_seq_used(s)); | |
c8d77183 SR |
8150 | |
8151 | kfree(s); | |
8152 | ||
8153 | return count; | |
8154 | } | |
8155 | ||
8156 | static const struct file_operations tracing_stats_fops = { | |
4d3435b8 | 8157 | .open = tracing_open_generic_tr, |
c8d77183 | 8158 | .read = tracing_stats_read, |
b444786f | 8159 | .llseek = generic_file_llseek, |
4d3435b8 | 8160 | .release = tracing_release_generic_tr, |
c8d77183 SR |
8161 | }; |
8162 | ||
bc0c38d1 SR |
8163 | #ifdef CONFIG_DYNAMIC_FTRACE |
8164 | ||
8165 | static ssize_t | |
b807c3d0 | 8166 | tracing_read_dyn_info(struct file *filp, char __user *ubuf, |
bc0c38d1 SR |
8167 | size_t cnt, loff_t *ppos) |
8168 | { | |
da537f0a SRV |
8169 | ssize_t ret; |
8170 | char *buf; | |
bc0c38d1 SR |
8171 | int r; |
8172 | ||
da537f0a SRV |
8173 | /* 256 should be plenty to hold the amount needed */ |
8174 | buf = kmalloc(256, GFP_KERNEL); | |
8175 | if (!buf) | |
8176 | return -ENOMEM; | |
b807c3d0 | 8177 | |
da537f0a SRV |
8178 | r = scnprintf(buf, 256, "%ld pages:%ld groups: %ld\n", |
8179 | ftrace_update_tot_cnt, | |
8180 | ftrace_number_of_pages, | |
8181 | ftrace_number_of_groups); | |
8182 | ||
8183 | ret = simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
8184 | kfree(buf); | |
8185 | return ret; | |
bc0c38d1 SR |
8186 | } |
8187 | ||
5e2336a0 | 8188 | static const struct file_operations tracing_dyn_info_fops = { |
4bf39a94 | 8189 | .open = tracing_open_generic, |
b807c3d0 | 8190 | .read = tracing_read_dyn_info, |
b444786f | 8191 | .llseek = generic_file_llseek, |
bc0c38d1 | 8192 | }; |
77fd5c15 | 8193 | #endif /* CONFIG_DYNAMIC_FTRACE */ |
bc0c38d1 | 8194 | |
77fd5c15 SRRH |
8195 | #if defined(CONFIG_TRACER_SNAPSHOT) && defined(CONFIG_DYNAMIC_FTRACE) |
8196 | static void | |
bca6c8d0 | 8197 | ftrace_snapshot(unsigned long ip, unsigned long parent_ip, |
b5f081b5 | 8198 | struct trace_array *tr, struct ftrace_probe_ops *ops, |
6e444319 | 8199 | void *data) |
77fd5c15 | 8200 | { |
cab50379 | 8201 | tracing_snapshot_instance(tr); |
77fd5c15 | 8202 | } |
bc0c38d1 | 8203 | |
77fd5c15 | 8204 | static void |
bca6c8d0 | 8205 | ftrace_count_snapshot(unsigned long ip, unsigned long parent_ip, |
b5f081b5 | 8206 | struct trace_array *tr, struct ftrace_probe_ops *ops, |
6e444319 | 8207 | void *data) |
bc0c38d1 | 8208 | { |
6e444319 | 8209 | struct ftrace_func_mapper *mapper = data; |
1a93f8bd | 8210 | long *count = NULL; |
77fd5c15 | 8211 | |
1a93f8bd SRV |
8212 | if (mapper) |
8213 | count = (long *)ftrace_func_mapper_find_ip(mapper, ip); | |
8214 | ||
8215 | if (count) { | |
8216 | ||
8217 | if (*count <= 0) | |
8218 | return; | |
bc0c38d1 | 8219 | |
77fd5c15 | 8220 | (*count)--; |
1a93f8bd | 8221 | } |
77fd5c15 | 8222 | |
cab50379 | 8223 | tracing_snapshot_instance(tr); |
77fd5c15 SRRH |
8224 | } |
8225 | ||
8226 | static int | |
8227 | ftrace_snapshot_print(struct seq_file *m, unsigned long ip, | |
8228 | struct ftrace_probe_ops *ops, void *data) | |
8229 | { | |
6e444319 | 8230 | struct ftrace_func_mapper *mapper = data; |
1a93f8bd | 8231 | long *count = NULL; |
77fd5c15 SRRH |
8232 | |
8233 | seq_printf(m, "%ps:", (void *)ip); | |
8234 | ||
fa6f0cc7 | 8235 | seq_puts(m, "snapshot"); |
77fd5c15 | 8236 | |
1a93f8bd SRV |
8237 | if (mapper) |
8238 | count = (long *)ftrace_func_mapper_find_ip(mapper, ip); | |
8239 | ||
8240 | if (count) | |
8241 | seq_printf(m, ":count=%ld\n", *count); | |
77fd5c15 | 8242 | else |
1a93f8bd | 8243 | seq_puts(m, ":unlimited\n"); |
77fd5c15 SRRH |
8244 | |
8245 | return 0; | |
8246 | } | |
8247 | ||
1a93f8bd | 8248 | static int |
b5f081b5 | 8249 | ftrace_snapshot_init(struct ftrace_probe_ops *ops, struct trace_array *tr, |
6e444319 | 8250 | unsigned long ip, void *init_data, void **data) |
1a93f8bd | 8251 | { |
6e444319 SRV |
8252 | struct ftrace_func_mapper *mapper = *data; |
8253 | ||
8254 | if (!mapper) { | |
8255 | mapper = allocate_ftrace_func_mapper(); | |
8256 | if (!mapper) | |
8257 | return -ENOMEM; | |
8258 | *data = mapper; | |
8259 | } | |
1a93f8bd | 8260 | |
6e444319 | 8261 | return ftrace_func_mapper_add_ip(mapper, ip, init_data); |
1a93f8bd SRV |
8262 | } |
8263 | ||
8264 | static void | |
b5f081b5 | 8265 | ftrace_snapshot_free(struct ftrace_probe_ops *ops, struct trace_array *tr, |
6e444319 | 8266 | unsigned long ip, void *data) |
1a93f8bd | 8267 | { |
6e444319 SRV |
8268 | struct ftrace_func_mapper *mapper = data; |
8269 | ||
8270 | if (!ip) { | |
8271 | if (!mapper) | |
8272 | return; | |
8273 | free_ftrace_func_mapper(mapper, NULL); | |
8274 | return; | |
8275 | } | |
1a93f8bd SRV |
8276 | |
8277 | ftrace_func_mapper_remove_ip(mapper, ip); | |
8278 | } | |
8279 | ||
77fd5c15 SRRH |
8280 | static struct ftrace_probe_ops snapshot_probe_ops = { |
8281 | .func = ftrace_snapshot, | |
8282 | .print = ftrace_snapshot_print, | |
8283 | }; | |
8284 | ||
8285 | static struct ftrace_probe_ops snapshot_count_probe_ops = { | |
8286 | .func = ftrace_count_snapshot, | |
8287 | .print = ftrace_snapshot_print, | |
1a93f8bd SRV |
8288 | .init = ftrace_snapshot_init, |
8289 | .free = ftrace_snapshot_free, | |
77fd5c15 SRRH |
8290 | }; |
8291 | ||
8292 | static int | |
04ec7bb6 | 8293 | ftrace_trace_snapshot_callback(struct trace_array *tr, struct ftrace_hash *hash, |
77fd5c15 SRRH |
8294 | char *glob, char *cmd, char *param, int enable) |
8295 | { | |
8296 | struct ftrace_probe_ops *ops; | |
8297 | void *count = (void *)-1; | |
8298 | char *number; | |
8299 | int ret; | |
8300 | ||
0f179765 SRV |
8301 | if (!tr) |
8302 | return -ENODEV; | |
8303 | ||
77fd5c15 SRRH |
8304 | /* hash funcs only work with set_ftrace_filter */ |
8305 | if (!enable) | |
8306 | return -EINVAL; | |
8307 | ||
8308 | ops = param ? &snapshot_count_probe_ops : &snapshot_probe_ops; | |
8309 | ||
d3d532d7 | 8310 | if (glob[0] == '!') |
7b60f3d8 | 8311 | return unregister_ftrace_function_probe_func(glob+1, tr, ops); |
77fd5c15 SRRH |
8312 | |
8313 | if (!param) | |
8314 | goto out_reg; | |
8315 | ||
8316 | number = strsep(¶m, ":"); | |
8317 | ||
8318 | if (!strlen(number)) | |
8319 | goto out_reg; | |
8320 | ||
8321 | /* | |
8322 | * We use the callback data field (which is a pointer) | |
8323 | * as our counter. | |
8324 | */ | |
8325 | ret = kstrtoul(number, 0, (unsigned long *)&count); | |
8326 | if (ret) | |
8327 | return ret; | |
8328 | ||
8329 | out_reg: | |
2824f503 | 8330 | ret = tracing_alloc_snapshot_instance(tr); |
df62db5b SRV |
8331 | if (ret < 0) |
8332 | goto out; | |
77fd5c15 | 8333 | |
4c174688 | 8334 | ret = register_ftrace_function_probe(glob, tr, ops, count); |
77fd5c15 | 8335 | |
df62db5b | 8336 | out: |
77fd5c15 SRRH |
8337 | return ret < 0 ? ret : 0; |
8338 | } | |
8339 | ||
8340 | static struct ftrace_func_command ftrace_snapshot_cmd = { | |
8341 | .name = "snapshot", | |
8342 | .func = ftrace_trace_snapshot_callback, | |
8343 | }; | |
8344 | ||
38de93ab | 8345 | static __init int register_snapshot_cmd(void) |
77fd5c15 SRRH |
8346 | { |
8347 | return register_ftrace_command(&ftrace_snapshot_cmd); | |
8348 | } | |
8349 | #else | |
38de93ab | 8350 | static inline __init int register_snapshot_cmd(void) { return 0; } |
77fd5c15 | 8351 | #endif /* defined(CONFIG_TRACER_SNAPSHOT) && defined(CONFIG_DYNAMIC_FTRACE) */ |
bc0c38d1 | 8352 | |
7eeafbca | 8353 | static struct dentry *tracing_get_dentry(struct trace_array *tr) |
bc0c38d1 | 8354 | { |
8434dc93 SRRH |
8355 | if (WARN_ON(!tr->dir)) |
8356 | return ERR_PTR(-ENODEV); | |
8357 | ||
8358 | /* Top directory uses NULL as the parent */ | |
8359 | if (tr->flags & TRACE_ARRAY_FL_GLOBAL) | |
8360 | return NULL; | |
8361 | ||
8362 | /* All sub buffers have a descriptor */ | |
2b6080f2 | 8363 | return tr->dir; |
bc0c38d1 SR |
8364 | } |
8365 | ||
2b6080f2 | 8366 | static struct dentry *tracing_dentry_percpu(struct trace_array *tr, int cpu) |
b04cc6b1 | 8367 | { |
b04cc6b1 FW |
8368 | struct dentry *d_tracer; |
8369 | ||
2b6080f2 SR |
8370 | if (tr->percpu_dir) |
8371 | return tr->percpu_dir; | |
b04cc6b1 | 8372 | |
7eeafbca | 8373 | d_tracer = tracing_get_dentry(tr); |
14a5ae40 | 8374 | if (IS_ERR(d_tracer)) |
b04cc6b1 FW |
8375 | return NULL; |
8376 | ||
8434dc93 | 8377 | tr->percpu_dir = tracefs_create_dir("per_cpu", d_tracer); |
b04cc6b1 | 8378 | |
24589e3a | 8379 | MEM_FAIL(!tr->percpu_dir, |
8434dc93 | 8380 | "Could not create tracefs directory 'per_cpu/%d'\n", cpu); |
b04cc6b1 | 8381 | |
2b6080f2 | 8382 | return tr->percpu_dir; |
b04cc6b1 FW |
8383 | } |
8384 | ||
649e9c70 ON |
8385 | static struct dentry * |
8386 | trace_create_cpu_file(const char *name, umode_t mode, struct dentry *parent, | |
8387 | void *data, long cpu, const struct file_operations *fops) | |
8388 | { | |
8389 | struct dentry *ret = trace_create_file(name, mode, parent, data, fops); | |
8390 | ||
8391 | if (ret) /* See tracing_get_cpu() */ | |
7682c918 | 8392 | d_inode(ret)->i_cdev = (void *)(cpu + 1); |
649e9c70 ON |
8393 | return ret; |
8394 | } | |
8395 | ||
2b6080f2 | 8396 | static void |
8434dc93 | 8397 | tracing_init_tracefs_percpu(struct trace_array *tr, long cpu) |
b04cc6b1 | 8398 | { |
2b6080f2 | 8399 | struct dentry *d_percpu = tracing_dentry_percpu(tr, cpu); |
5452af66 | 8400 | struct dentry *d_cpu; |
dd49a38c | 8401 | char cpu_dir[30]; /* 30 characters should be more than enough */ |
b04cc6b1 | 8402 | |
0a3d7ce7 NK |
8403 | if (!d_percpu) |
8404 | return; | |
8405 | ||
dd49a38c | 8406 | snprintf(cpu_dir, 30, "cpu%ld", cpu); |
8434dc93 | 8407 | d_cpu = tracefs_create_dir(cpu_dir, d_percpu); |
8656e7a2 | 8408 | if (!d_cpu) { |
a395d6a7 | 8409 | pr_warn("Could not create tracefs '%s' entry\n", cpu_dir); |
8656e7a2 FW |
8410 | return; |
8411 | } | |
b04cc6b1 | 8412 | |
8656e7a2 | 8413 | /* per cpu trace_pipe */ |
649e9c70 | 8414 | trace_create_cpu_file("trace_pipe", 0444, d_cpu, |
15544209 | 8415 | tr, cpu, &tracing_pipe_fops); |
b04cc6b1 FW |
8416 | |
8417 | /* per cpu trace */ | |
649e9c70 | 8418 | trace_create_cpu_file("trace", 0644, d_cpu, |
6484c71c | 8419 | tr, cpu, &tracing_fops); |
7f96f93f | 8420 | |
649e9c70 | 8421 | trace_create_cpu_file("trace_pipe_raw", 0444, d_cpu, |
46ef2be0 | 8422 | tr, cpu, &tracing_buffers_fops); |
7f96f93f | 8423 | |
649e9c70 | 8424 | trace_create_cpu_file("stats", 0444, d_cpu, |
4d3435b8 | 8425 | tr, cpu, &tracing_stats_fops); |
438ced17 | 8426 | |
649e9c70 | 8427 | trace_create_cpu_file("buffer_size_kb", 0444, d_cpu, |
0bc392ee | 8428 | tr, cpu, &tracing_entries_fops); |
f1affcaa SRRH |
8429 | |
8430 | #ifdef CONFIG_TRACER_SNAPSHOT | |
649e9c70 | 8431 | trace_create_cpu_file("snapshot", 0644, d_cpu, |
6484c71c | 8432 | tr, cpu, &snapshot_fops); |
6de58e62 | 8433 | |
649e9c70 | 8434 | trace_create_cpu_file("snapshot_raw", 0444, d_cpu, |
46ef2be0 | 8435 | tr, cpu, &snapshot_raw_fops); |
f1affcaa | 8436 | #endif |
b04cc6b1 FW |
8437 | } |
8438 | ||
60a11774 SR |
8439 | #ifdef CONFIG_FTRACE_SELFTEST |
8440 | /* Let selftest have access to static functions in this file */ | |
8441 | #include "trace_selftest.c" | |
8442 | #endif | |
8443 | ||
577b785f SR |
8444 | static ssize_t |
8445 | trace_options_read(struct file *filp, char __user *ubuf, size_t cnt, | |
8446 | loff_t *ppos) | |
8447 | { | |
8448 | struct trace_option_dentry *topt = filp->private_data; | |
8449 | char *buf; | |
8450 | ||
8451 | if (topt->flags->val & topt->opt->bit) | |
8452 | buf = "1\n"; | |
8453 | else | |
8454 | buf = "0\n"; | |
8455 | ||
8456 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, 2); | |
8457 | } | |
8458 | ||
8459 | static ssize_t | |
8460 | trace_options_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
8461 | loff_t *ppos) | |
8462 | { | |
8463 | struct trace_option_dentry *topt = filp->private_data; | |
8464 | unsigned long val; | |
577b785f SR |
8465 | int ret; |
8466 | ||
22fe9b54 PH |
8467 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
8468 | if (ret) | |
577b785f SR |
8469 | return ret; |
8470 | ||
8d18eaaf LZ |
8471 | if (val != 0 && val != 1) |
8472 | return -EINVAL; | |
577b785f | 8473 | |
8d18eaaf | 8474 | if (!!(topt->flags->val & topt->opt->bit) != val) { |
577b785f | 8475 | mutex_lock(&trace_types_lock); |
8c1a49ae | 8476 | ret = __set_tracer_option(topt->tr, topt->flags, |
c757bea9 | 8477 | topt->opt, !val); |
577b785f SR |
8478 | mutex_unlock(&trace_types_lock); |
8479 | if (ret) | |
8480 | return ret; | |
577b785f SR |
8481 | } |
8482 | ||
8483 | *ppos += cnt; | |
8484 | ||
8485 | return cnt; | |
8486 | } | |
8487 | ||
8488 | ||
8489 | static const struct file_operations trace_options_fops = { | |
8490 | .open = tracing_open_generic, | |
8491 | .read = trace_options_read, | |
8492 | .write = trace_options_write, | |
b444786f | 8493 | .llseek = generic_file_llseek, |
577b785f SR |
8494 | }; |
8495 | ||
9a38a885 SRRH |
8496 | /* |
8497 | * In order to pass in both the trace_array descriptor as well as the index | |
8498 | * to the flag that the trace option file represents, the trace_array | |
8499 | * has a character array of trace_flags_index[], which holds the index | |
8500 | * of the bit for the flag it represents. index[0] == 0, index[1] == 1, etc. | |
8501 | * The address of this character array is passed to the flag option file | |
8502 | * read/write callbacks. | |
8503 | * | |
8504 | * In order to extract both the index and the trace_array descriptor, | |
8505 | * get_tr_index() uses the following algorithm. | |
8506 | * | |
8507 | * idx = *ptr; | |
8508 | * | |
8509 | * As the pointer itself contains the address of the index (remember | |
8510 | * index[1] == 1). | |
8511 | * | |
8512 | * Then to get the trace_array descriptor, by subtracting that index | |
8513 | * from the ptr, we get to the start of the index itself. | |
8514 | * | |
8515 | * ptr - idx == &index[0] | |
8516 | * | |
8517 | * Then a simple container_of() from that pointer gets us to the | |
8518 | * trace_array descriptor. | |
8519 | */ | |
8520 | static void get_tr_index(void *data, struct trace_array **ptr, | |
8521 | unsigned int *pindex) | |
8522 | { | |
8523 | *pindex = *(unsigned char *)data; | |
8524 | ||
8525 | *ptr = container_of(data - *pindex, struct trace_array, | |
8526 | trace_flags_index); | |
8527 | } | |
8528 | ||
a8259075 SR |
8529 | static ssize_t |
8530 | trace_options_core_read(struct file *filp, char __user *ubuf, size_t cnt, | |
8531 | loff_t *ppos) | |
8532 | { | |
9a38a885 SRRH |
8533 | void *tr_index = filp->private_data; |
8534 | struct trace_array *tr; | |
8535 | unsigned int index; | |
a8259075 SR |
8536 | char *buf; |
8537 | ||
9a38a885 SRRH |
8538 | get_tr_index(tr_index, &tr, &index); |
8539 | ||
8540 | if (tr->trace_flags & (1 << index)) | |
a8259075 SR |
8541 | buf = "1\n"; |
8542 | else | |
8543 | buf = "0\n"; | |
8544 | ||
8545 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, 2); | |
8546 | } | |
8547 | ||
8548 | static ssize_t | |
8549 | trace_options_core_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
8550 | loff_t *ppos) | |
8551 | { | |
9a38a885 SRRH |
8552 | void *tr_index = filp->private_data; |
8553 | struct trace_array *tr; | |
8554 | unsigned int index; | |
a8259075 SR |
8555 | unsigned long val; |
8556 | int ret; | |
8557 | ||
9a38a885 SRRH |
8558 | get_tr_index(tr_index, &tr, &index); |
8559 | ||
22fe9b54 PH |
8560 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
8561 | if (ret) | |
a8259075 SR |
8562 | return ret; |
8563 | ||
f2d84b65 | 8564 | if (val != 0 && val != 1) |
a8259075 | 8565 | return -EINVAL; |
69d34da2 | 8566 | |
3a53acf1 | 8567 | mutex_lock(&event_mutex); |
69d34da2 | 8568 | mutex_lock(&trace_types_lock); |
2b6080f2 | 8569 | ret = set_tracer_flag(tr, 1 << index, val); |
69d34da2 | 8570 | mutex_unlock(&trace_types_lock); |
3a53acf1 | 8571 | mutex_unlock(&event_mutex); |
a8259075 | 8572 | |
613f04a0 SRRH |
8573 | if (ret < 0) |
8574 | return ret; | |
8575 | ||
a8259075 SR |
8576 | *ppos += cnt; |
8577 | ||
8578 | return cnt; | |
8579 | } | |
8580 | ||
a8259075 SR |
8581 | static const struct file_operations trace_options_core_fops = { |
8582 | .open = tracing_open_generic, | |
8583 | .read = trace_options_core_read, | |
8584 | .write = trace_options_core_write, | |
b444786f | 8585 | .llseek = generic_file_llseek, |
a8259075 SR |
8586 | }; |
8587 | ||
5452af66 | 8588 | struct dentry *trace_create_file(const char *name, |
f4ae40a6 | 8589 | umode_t mode, |
5452af66 FW |
8590 | struct dentry *parent, |
8591 | void *data, | |
8592 | const struct file_operations *fops) | |
8593 | { | |
8594 | struct dentry *ret; | |
8595 | ||
8434dc93 | 8596 | ret = tracefs_create_file(name, mode, parent, data, fops); |
5452af66 | 8597 | if (!ret) |
a395d6a7 | 8598 | pr_warn("Could not create tracefs '%s' entry\n", name); |
5452af66 FW |
8599 | |
8600 | return ret; | |
8601 | } | |
8602 | ||
8603 | ||
2b6080f2 | 8604 | static struct dentry *trace_options_init_dentry(struct trace_array *tr) |
a8259075 SR |
8605 | { |
8606 | struct dentry *d_tracer; | |
a8259075 | 8607 | |
2b6080f2 SR |
8608 | if (tr->options) |
8609 | return tr->options; | |
a8259075 | 8610 | |
7eeafbca | 8611 | d_tracer = tracing_get_dentry(tr); |
14a5ae40 | 8612 | if (IS_ERR(d_tracer)) |
a8259075 SR |
8613 | return NULL; |
8614 | ||
8434dc93 | 8615 | tr->options = tracefs_create_dir("options", d_tracer); |
2b6080f2 | 8616 | if (!tr->options) { |
a395d6a7 | 8617 | pr_warn("Could not create tracefs directory 'options'\n"); |
a8259075 SR |
8618 | return NULL; |
8619 | } | |
8620 | ||
2b6080f2 | 8621 | return tr->options; |
a8259075 SR |
8622 | } |
8623 | ||
577b785f | 8624 | static void |
2b6080f2 SR |
8625 | create_trace_option_file(struct trace_array *tr, |
8626 | struct trace_option_dentry *topt, | |
577b785f SR |
8627 | struct tracer_flags *flags, |
8628 | struct tracer_opt *opt) | |
8629 | { | |
8630 | struct dentry *t_options; | |
577b785f | 8631 | |
2b6080f2 | 8632 | t_options = trace_options_init_dentry(tr); |
577b785f SR |
8633 | if (!t_options) |
8634 | return; | |
8635 | ||
8636 | topt->flags = flags; | |
8637 | topt->opt = opt; | |
2b6080f2 | 8638 | topt->tr = tr; |
577b785f | 8639 | |
5452af66 | 8640 | topt->entry = trace_create_file(opt->name, 0644, t_options, topt, |
577b785f SR |
8641 | &trace_options_fops); |
8642 | ||
577b785f SR |
8643 | } |
8644 | ||
37aea98b | 8645 | static void |
2b6080f2 | 8646 | create_trace_option_files(struct trace_array *tr, struct tracer *tracer) |
577b785f SR |
8647 | { |
8648 | struct trace_option_dentry *topts; | |
37aea98b | 8649 | struct trace_options *tr_topts; |
577b785f SR |
8650 | struct tracer_flags *flags; |
8651 | struct tracer_opt *opts; | |
8652 | int cnt; | |
37aea98b | 8653 | int i; |
577b785f SR |
8654 | |
8655 | if (!tracer) | |
37aea98b | 8656 | return; |
577b785f SR |
8657 | |
8658 | flags = tracer->flags; | |
8659 | ||
8660 | if (!flags || !flags->opts) | |
37aea98b SRRH |
8661 | return; |
8662 | ||
8663 | /* | |
8664 | * If this is an instance, only create flags for tracers | |
8665 | * the instance may have. | |
8666 | */ | |
8667 | if (!trace_ok_for_array(tracer, tr)) | |
8668 | return; | |
8669 | ||
8670 | for (i = 0; i < tr->nr_topts; i++) { | |
d39cdd20 CH |
8671 | /* Make sure there's no duplicate flags. */ |
8672 | if (WARN_ON_ONCE(tr->topts[i].tracer->flags == tracer->flags)) | |
37aea98b SRRH |
8673 | return; |
8674 | } | |
577b785f SR |
8675 | |
8676 | opts = flags->opts; | |
8677 | ||
8678 | for (cnt = 0; opts[cnt].name; cnt++) | |
8679 | ; | |
8680 | ||
0cfe8245 | 8681 | topts = kcalloc(cnt + 1, sizeof(*topts), GFP_KERNEL); |
577b785f | 8682 | if (!topts) |
37aea98b SRRH |
8683 | return; |
8684 | ||
8685 | tr_topts = krealloc(tr->topts, sizeof(*tr->topts) * (tr->nr_topts + 1), | |
8686 | GFP_KERNEL); | |
8687 | if (!tr_topts) { | |
8688 | kfree(topts); | |
8689 | return; | |
8690 | } | |
8691 | ||
8692 | tr->topts = tr_topts; | |
8693 | tr->topts[tr->nr_topts].tracer = tracer; | |
8694 | tr->topts[tr->nr_topts].topts = topts; | |
8695 | tr->nr_topts++; | |
577b785f | 8696 | |
41d9c0be | 8697 | for (cnt = 0; opts[cnt].name; cnt++) { |
2b6080f2 | 8698 | create_trace_option_file(tr, &topts[cnt], flags, |
577b785f | 8699 | &opts[cnt]); |
24589e3a | 8700 | MEM_FAIL(topts[cnt].entry == NULL, |
41d9c0be SRRH |
8701 | "Failed to create trace option: %s", |
8702 | opts[cnt].name); | |
8703 | } | |
577b785f SR |
8704 | } |
8705 | ||
a8259075 | 8706 | static struct dentry * |
2b6080f2 SR |
8707 | create_trace_option_core_file(struct trace_array *tr, |
8708 | const char *option, long index) | |
a8259075 SR |
8709 | { |
8710 | struct dentry *t_options; | |
a8259075 | 8711 | |
2b6080f2 | 8712 | t_options = trace_options_init_dentry(tr); |
a8259075 SR |
8713 | if (!t_options) |
8714 | return NULL; | |
8715 | ||
9a38a885 SRRH |
8716 | return trace_create_file(option, 0644, t_options, |
8717 | (void *)&tr->trace_flags_index[index], | |
8718 | &trace_options_core_fops); | |
a8259075 SR |
8719 | } |
8720 | ||
16270145 | 8721 | static void create_trace_options_dir(struct trace_array *tr) |
a8259075 SR |
8722 | { |
8723 | struct dentry *t_options; | |
16270145 | 8724 | bool top_level = tr == &global_trace; |
a8259075 SR |
8725 | int i; |
8726 | ||
2b6080f2 | 8727 | t_options = trace_options_init_dentry(tr); |
a8259075 SR |
8728 | if (!t_options) |
8729 | return; | |
8730 | ||
16270145 SRRH |
8731 | for (i = 0; trace_options[i]; i++) { |
8732 | if (top_level || | |
8733 | !((1 << i) & TOP_LEVEL_TRACE_FLAGS)) | |
8734 | create_trace_option_core_file(tr, trace_options[i], i); | |
8735 | } | |
a8259075 SR |
8736 | } |
8737 | ||
499e5470 SR |
8738 | static ssize_t |
8739 | rb_simple_read(struct file *filp, char __user *ubuf, | |
8740 | size_t cnt, loff_t *ppos) | |
8741 | { | |
348f0fc2 | 8742 | struct trace_array *tr = filp->private_data; |
499e5470 SR |
8743 | char buf[64]; |
8744 | int r; | |
8745 | ||
10246fa3 | 8746 | r = tracer_tracing_is_on(tr); |
499e5470 SR |
8747 | r = sprintf(buf, "%d\n", r); |
8748 | ||
8749 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
8750 | } | |
8751 | ||
8752 | static ssize_t | |
8753 | rb_simple_write(struct file *filp, const char __user *ubuf, | |
8754 | size_t cnt, loff_t *ppos) | |
8755 | { | |
348f0fc2 | 8756 | struct trace_array *tr = filp->private_data; |
13292494 | 8757 | struct trace_buffer *buffer = tr->array_buffer.buffer; |
499e5470 SR |
8758 | unsigned long val; |
8759 | int ret; | |
8760 | ||
8761 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); | |
8762 | if (ret) | |
8763 | return ret; | |
8764 | ||
8765 | if (buffer) { | |
2df8f8a6 | 8766 | mutex_lock(&trace_types_lock); |
f143641b SRV |
8767 | if (!!val == tracer_tracing_is_on(tr)) { |
8768 | val = 0; /* do nothing */ | |
8769 | } else if (val) { | |
10246fa3 | 8770 | tracer_tracing_on(tr); |
2b6080f2 SR |
8771 | if (tr->current_trace->start) |
8772 | tr->current_trace->start(tr); | |
2df8f8a6 | 8773 | } else { |
10246fa3 | 8774 | tracer_tracing_off(tr); |
2b6080f2 SR |
8775 | if (tr->current_trace->stop) |
8776 | tr->current_trace->stop(tr); | |
2df8f8a6 SR |
8777 | } |
8778 | mutex_unlock(&trace_types_lock); | |
499e5470 SR |
8779 | } |
8780 | ||
8781 | (*ppos)++; | |
8782 | ||
8783 | return cnt; | |
8784 | } | |
8785 | ||
8786 | static const struct file_operations rb_simple_fops = { | |
7b85af63 | 8787 | .open = tracing_open_generic_tr, |
499e5470 SR |
8788 | .read = rb_simple_read, |
8789 | .write = rb_simple_write, | |
7b85af63 | 8790 | .release = tracing_release_generic_tr, |
499e5470 SR |
8791 | .llseek = default_llseek, |
8792 | }; | |
8793 | ||
03329f99 SRV |
8794 | static ssize_t |
8795 | buffer_percent_read(struct file *filp, char __user *ubuf, | |
8796 | size_t cnt, loff_t *ppos) | |
8797 | { | |
8798 | struct trace_array *tr = filp->private_data; | |
8799 | char buf[64]; | |
8800 | int r; | |
8801 | ||
8802 | r = tr->buffer_percent; | |
8803 | r = sprintf(buf, "%d\n", r); | |
8804 | ||
8805 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
8806 | } | |
8807 | ||
8808 | static ssize_t | |
8809 | buffer_percent_write(struct file *filp, const char __user *ubuf, | |
8810 | size_t cnt, loff_t *ppos) | |
8811 | { | |
8812 | struct trace_array *tr = filp->private_data; | |
8813 | unsigned long val; | |
8814 | int ret; | |
8815 | ||
8816 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); | |
8817 | if (ret) | |
8818 | return ret; | |
8819 | ||
8820 | if (val > 100) | |
8821 | return -EINVAL; | |
8822 | ||
8823 | if (!val) | |
8824 | val = 1; | |
8825 | ||
8826 | tr->buffer_percent = val; | |
8827 | ||
8828 | (*ppos)++; | |
8829 | ||
8830 | return cnt; | |
8831 | } | |
8832 | ||
8833 | static const struct file_operations buffer_percent_fops = { | |
8834 | .open = tracing_open_generic_tr, | |
8835 | .read = buffer_percent_read, | |
8836 | .write = buffer_percent_write, | |
8837 | .release = tracing_release_generic_tr, | |
8838 | .llseek = default_llseek, | |
8839 | }; | |
8840 | ||
ff585c5b | 8841 | static struct dentry *trace_instance_dir; |
277ba044 SR |
8842 | |
8843 | static void | |
8434dc93 | 8844 | init_tracer_tracefs(struct trace_array *tr, struct dentry *d_tracer); |
277ba044 | 8845 | |
55034cd6 | 8846 | static int |
1c5eb448 | 8847 | allocate_trace_buffer(struct trace_array *tr, struct array_buffer *buf, int size) |
277ba044 SR |
8848 | { |
8849 | enum ring_buffer_flags rb_flags; | |
737223fb | 8850 | |
983f938a | 8851 | rb_flags = tr->trace_flags & TRACE_ITER_OVERWRITE ? RB_FL_OVERWRITE : 0; |
737223fb | 8852 | |
dced341b SRRH |
8853 | buf->tr = tr; |
8854 | ||
55034cd6 SRRH |
8855 | buf->buffer = ring_buffer_alloc(size, rb_flags); |
8856 | if (!buf->buffer) | |
8857 | return -ENOMEM; | |
737223fb | 8858 | |
55034cd6 SRRH |
8859 | buf->data = alloc_percpu(struct trace_array_cpu); |
8860 | if (!buf->data) { | |
8861 | ring_buffer_free(buf->buffer); | |
4397f045 | 8862 | buf->buffer = NULL; |
55034cd6 SRRH |
8863 | return -ENOMEM; |
8864 | } | |
737223fb | 8865 | |
737223fb | 8866 | /* Allocate the first page for all buffers */ |
1c5eb448 SRV |
8867 | set_buffer_entries(&tr->array_buffer, |
8868 | ring_buffer_size(tr->array_buffer.buffer, 0)); | |
737223fb | 8869 | |
55034cd6 SRRH |
8870 | return 0; |
8871 | } | |
737223fb | 8872 | |
55034cd6 SRRH |
8873 | static int allocate_trace_buffers(struct trace_array *tr, int size) |
8874 | { | |
8875 | int ret; | |
737223fb | 8876 | |
1c5eb448 | 8877 | ret = allocate_trace_buffer(tr, &tr->array_buffer, size); |
55034cd6 SRRH |
8878 | if (ret) |
8879 | return ret; | |
737223fb | 8880 | |
55034cd6 SRRH |
8881 | #ifdef CONFIG_TRACER_MAX_TRACE |
8882 | ret = allocate_trace_buffer(tr, &tr->max_buffer, | |
8883 | allocate_snapshot ? size : 1); | |
24589e3a | 8884 | if (MEM_FAIL(ret, "Failed to allocate trace buffer\n")) { |
1c5eb448 SRV |
8885 | ring_buffer_free(tr->array_buffer.buffer); |
8886 | tr->array_buffer.buffer = NULL; | |
8887 | free_percpu(tr->array_buffer.data); | |
8888 | tr->array_buffer.data = NULL; | |
55034cd6 SRRH |
8889 | return -ENOMEM; |
8890 | } | |
8891 | tr->allocated_snapshot = allocate_snapshot; | |
737223fb | 8892 | |
55034cd6 SRRH |
8893 | /* |
8894 | * Only the top level trace array gets its snapshot allocated | |
8895 | * from the kernel command line. | |
8896 | */ | |
8897 | allocate_snapshot = false; | |
737223fb | 8898 | #endif |
11f5efc3 | 8899 | |
55034cd6 | 8900 | return 0; |
737223fb SRRH |
8901 | } |
8902 | ||
1c5eb448 | 8903 | static void free_trace_buffer(struct array_buffer *buf) |
f0b70cc4 SRRH |
8904 | { |
8905 | if (buf->buffer) { | |
8906 | ring_buffer_free(buf->buffer); | |
8907 | buf->buffer = NULL; | |
8908 | free_percpu(buf->data); | |
8909 | buf->data = NULL; | |
8910 | } | |
8911 | } | |
8912 | ||
23aaa3c1 SRRH |
8913 | static void free_trace_buffers(struct trace_array *tr) |
8914 | { | |
8915 | if (!tr) | |
8916 | return; | |
8917 | ||
1c5eb448 | 8918 | free_trace_buffer(&tr->array_buffer); |
23aaa3c1 SRRH |
8919 | |
8920 | #ifdef CONFIG_TRACER_MAX_TRACE | |
f0b70cc4 | 8921 | free_trace_buffer(&tr->max_buffer); |
23aaa3c1 SRRH |
8922 | #endif |
8923 | } | |
8924 | ||
9a38a885 SRRH |
8925 | static void init_trace_flags_index(struct trace_array *tr) |
8926 | { | |
8927 | int i; | |
8928 | ||
8929 | /* Used by the trace options files */ | |
8930 | for (i = 0; i < TRACE_FLAGS_MAX_SIZE; i++) | |
8931 | tr->trace_flags_index[i] = i; | |
8932 | } | |
8933 | ||
37aea98b SRRH |
8934 | static void __update_tracer_options(struct trace_array *tr) |
8935 | { | |
8936 | struct tracer *t; | |
8937 | ||
8938 | for (t = trace_types; t; t = t->next) | |
8939 | add_tracer_options(tr, t); | |
8940 | } | |
8941 | ||
8942 | static void update_tracer_options(struct trace_array *tr) | |
8943 | { | |
8944 | mutex_lock(&trace_types_lock); | |
8945 | __update_tracer_options(tr); | |
8946 | mutex_unlock(&trace_types_lock); | |
8947 | } | |
8948 | ||
89c95fce TZ |
8949 | /* Must have trace_types_lock held */ |
8950 | struct trace_array *trace_array_find(const char *instance) | |
8951 | { | |
8952 | struct trace_array *tr, *found = NULL; | |
8953 | ||
8954 | list_for_each_entry(tr, &ftrace_trace_arrays, list) { | |
8955 | if (tr->name && strcmp(tr->name, instance) == 0) { | |
8956 | found = tr; | |
8957 | break; | |
8958 | } | |
8959 | } | |
8960 | ||
8961 | return found; | |
8962 | } | |
8963 | ||
8964 | struct trace_array *trace_array_find_get(const char *instance) | |
8965 | { | |
8966 | struct trace_array *tr; | |
8967 | ||
8968 | mutex_lock(&trace_types_lock); | |
8969 | tr = trace_array_find(instance); | |
8970 | if (tr) | |
8971 | tr->ref++; | |
8972 | mutex_unlock(&trace_types_lock); | |
8973 | ||
8974 | return tr; | |
8975 | } | |
8976 | ||
4114fbfd MH |
8977 | static int trace_array_create_dir(struct trace_array *tr) |
8978 | { | |
8979 | int ret; | |
8980 | ||
8981 | tr->dir = tracefs_create_dir(tr->name, trace_instance_dir); | |
8982 | if (!tr->dir) | |
8983 | return -EINVAL; | |
8984 | ||
8985 | ret = event_trace_add_tracer(tr->dir, tr); | |
8986 | if (ret) | |
8987 | tracefs_remove(tr->dir); | |
8988 | ||
8989 | init_tracer_tracefs(tr, tr->dir); | |
8990 | __update_tracer_options(tr); | |
8991 | ||
8992 | return ret; | |
8993 | } | |
8994 | ||
28879787 | 8995 | static struct trace_array *trace_array_create(const char *name) |
737223fb | 8996 | { |
277ba044 SR |
8997 | struct trace_array *tr; |
8998 | int ret; | |
277ba044 | 8999 | |
277ba044 SR |
9000 | ret = -ENOMEM; |
9001 | tr = kzalloc(sizeof(*tr), GFP_KERNEL); | |
9002 | if (!tr) | |
28879787 | 9003 | return ERR_PTR(ret); |
277ba044 SR |
9004 | |
9005 | tr->name = kstrdup(name, GFP_KERNEL); | |
9006 | if (!tr->name) | |
9007 | goto out_free_tr; | |
9008 | ||
ccfe9e42 AL |
9009 | if (!alloc_cpumask_var(&tr->tracing_cpumask, GFP_KERNEL)) |
9010 | goto out_free_tr; | |
9011 | ||
20550622 | 9012 | tr->trace_flags = global_trace.trace_flags & ~ZEROED_TRACE_FLAGS; |
983f938a | 9013 | |
ccfe9e42 AL |
9014 | cpumask_copy(tr->tracing_cpumask, cpu_all_mask); |
9015 | ||
277ba044 SR |
9016 | raw_spin_lock_init(&tr->start_lock); |
9017 | ||
0b9b12c1 SRRH |
9018 | tr->max_lock = (arch_spinlock_t)__ARCH_SPIN_LOCK_UNLOCKED; |
9019 | ||
277ba044 SR |
9020 | tr->current_trace = &nop_trace; |
9021 | ||
9022 | INIT_LIST_HEAD(&tr->systems); | |
9023 | INIT_LIST_HEAD(&tr->events); | |
067fe038 | 9024 | INIT_LIST_HEAD(&tr->hist_vars); |
2f754e77 | 9025 | INIT_LIST_HEAD(&tr->err_log); |
277ba044 | 9026 | |
737223fb | 9027 | if (allocate_trace_buffers(tr, trace_buf_size) < 0) |
277ba044 SR |
9028 | goto out_free_tr; |
9029 | ||
4114fbfd | 9030 | if (ftrace_allocate_ftrace_ops(tr) < 0) |
277ba044 SR |
9031 | goto out_free_tr; |
9032 | ||
04ec7bb6 SRV |
9033 | ftrace_init_trace_array(tr); |
9034 | ||
9a38a885 | 9035 | init_trace_flags_index(tr); |
4114fbfd MH |
9036 | |
9037 | if (trace_instance_dir) { | |
9038 | ret = trace_array_create_dir(tr); | |
9039 | if (ret) | |
9040 | goto out_free_tr; | |
720dee53 MH |
9041 | } else |
9042 | __trace_early_add_events(tr); | |
277ba044 SR |
9043 | |
9044 | list_add(&tr->list, &ftrace_trace_arrays); | |
9045 | ||
28879787 DI |
9046 | tr->ref++; |
9047 | ||
f45d1225 | 9048 | return tr; |
277ba044 SR |
9049 | |
9050 | out_free_tr: | |
4114fbfd | 9051 | ftrace_free_ftrace_ops(tr); |
23aaa3c1 | 9052 | free_trace_buffers(tr); |
ccfe9e42 | 9053 | free_cpumask_var(tr->tracing_cpumask); |
277ba044 SR |
9054 | kfree(tr->name); |
9055 | kfree(tr); | |
9056 | ||
f45d1225 DI |
9057 | return ERR_PTR(ret); |
9058 | } | |
277ba044 | 9059 | |
f45d1225 DI |
9060 | static int instance_mkdir(const char *name) |
9061 | { | |
28879787 DI |
9062 | struct trace_array *tr; |
9063 | int ret; | |
9064 | ||
9065 | mutex_lock(&event_mutex); | |
9066 | mutex_lock(&trace_types_lock); | |
9067 | ||
9068 | ret = -EEXIST; | |
89c95fce TZ |
9069 | if (trace_array_find(name)) |
9070 | goto out_unlock; | |
28879787 DI |
9071 | |
9072 | tr = trace_array_create(name); | |
9073 | ||
9074 | ret = PTR_ERR_OR_ZERO(tr); | |
9075 | ||
9076 | out_unlock: | |
9077 | mutex_unlock(&trace_types_lock); | |
9078 | mutex_unlock(&event_mutex); | |
9079 | return ret; | |
9080 | } | |
9081 | ||
9082 | /** | |
9083 | * trace_array_get_by_name - Create/Lookup a trace array, given its name. | |
9084 | * @name: The name of the trace array to be looked up/created. | |
9085 | * | |
9086 | * Returns pointer to trace array with given name. | |
9087 | * NULL, if it cannot be created. | |
9088 | * | |
9089 | * NOTE: This function increments the reference counter associated with the | |
9090 | * trace array returned. This makes sure it cannot be freed while in use. | |
9091 | * Use trace_array_put() once the trace array is no longer needed. | |
28394da2 SRV |
9092 | * If the trace_array is to be freed, trace_array_destroy() needs to |
9093 | * be called after the trace_array_put(), or simply let user space delete | |
9094 | * it from the tracefs instances directory. But until the | |
9095 | * trace_array_put() is called, user space can not delete it. | |
28879787 DI |
9096 | * |
9097 | */ | |
9098 | struct trace_array *trace_array_get_by_name(const char *name) | |
9099 | { | |
9100 | struct trace_array *tr; | |
9101 | ||
9102 | mutex_lock(&event_mutex); | |
9103 | mutex_lock(&trace_types_lock); | |
9104 | ||
9105 | list_for_each_entry(tr, &ftrace_trace_arrays, list) { | |
9106 | if (tr->name && strcmp(tr->name, name) == 0) | |
9107 | goto out_unlock; | |
9108 | } | |
9109 | ||
9110 | tr = trace_array_create(name); | |
9111 | ||
9112 | if (IS_ERR(tr)) | |
9113 | tr = NULL; | |
9114 | out_unlock: | |
9115 | if (tr) | |
9116 | tr->ref++; | |
9117 | ||
9118 | mutex_unlock(&trace_types_lock); | |
9119 | mutex_unlock(&event_mutex); | |
9120 | return tr; | |
277ba044 | 9121 | } |
28879787 | 9122 | EXPORT_SYMBOL_GPL(trace_array_get_by_name); |
277ba044 | 9123 | |
f45d1225 | 9124 | static int __remove_instance(struct trace_array *tr) |
0c8916c3 | 9125 | { |
37aea98b | 9126 | int i; |
0c8916c3 | 9127 | |
28879787 | 9128 | /* Reference counter for a newly created trace array = 1. */ |
7ef282e0 | 9129 | if (tr->ref > 1 || (tr->current_trace && tr->trace_ref)) |
f45d1225 | 9130 | return -EBUSY; |
a695cb58 | 9131 | |
0c8916c3 SR |
9132 | list_del(&tr->list); |
9133 | ||
20550622 SRRH |
9134 | /* Disable all the flags that were enabled coming in */ |
9135 | for (i = 0; i < TRACE_FLAGS_MAX_SIZE; i++) { | |
9136 | if ((1 << i) & ZEROED_TRACE_FLAGS) | |
9137 | set_tracer_flag(tr, 1 << i, 0); | |
9138 | } | |
9139 | ||
6b450d25 | 9140 | tracing_set_nop(tr); |
a0e6369e | 9141 | clear_ftrace_function_probes(tr); |
0c8916c3 | 9142 | event_trace_del_tracer(tr); |
d879d0b8 | 9143 | ftrace_clear_pids(tr); |
591dffda | 9144 | ftrace_destroy_function_files(tr); |
a3d1e7eb | 9145 | tracefs_remove(tr->dir); |
20344c54 | 9146 | free_percpu(tr->last_func_repeats); |
a9fcaaac | 9147 | free_trace_buffers(tr); |
0c8916c3 | 9148 | |
37aea98b SRRH |
9149 | for (i = 0; i < tr->nr_topts; i++) { |
9150 | kfree(tr->topts[i].topts); | |
9151 | } | |
9152 | kfree(tr->topts); | |
9153 | ||
db9108e0 | 9154 | free_cpumask_var(tr->tracing_cpumask); |
0c8916c3 SR |
9155 | kfree(tr->name); |
9156 | kfree(tr); | |
9157 | ||
f45d1225 DI |
9158 | return 0; |
9159 | } | |
9160 | ||
e585e646 | 9161 | int trace_array_destroy(struct trace_array *this_tr) |
f45d1225 | 9162 | { |
e585e646 | 9163 | struct trace_array *tr; |
f45d1225 DI |
9164 | int ret; |
9165 | ||
e585e646 | 9166 | if (!this_tr) |
f45d1225 DI |
9167 | return -EINVAL; |
9168 | ||
9169 | mutex_lock(&event_mutex); | |
9170 | mutex_lock(&trace_types_lock); | |
9171 | ||
e585e646 DI |
9172 | ret = -ENODEV; |
9173 | ||
9174 | /* Making sure trace array exists before destroying it. */ | |
9175 | list_for_each_entry(tr, &ftrace_trace_arrays, list) { | |
9176 | if (tr == this_tr) { | |
9177 | ret = __remove_instance(tr); | |
9178 | break; | |
9179 | } | |
9180 | } | |
f45d1225 DI |
9181 | |
9182 | mutex_unlock(&trace_types_lock); | |
9183 | mutex_unlock(&event_mutex); | |
9184 | ||
9185 | return ret; | |
9186 | } | |
9187 | EXPORT_SYMBOL_GPL(trace_array_destroy); | |
9188 | ||
9189 | static int instance_rmdir(const char *name) | |
9190 | { | |
9191 | struct trace_array *tr; | |
9192 | int ret; | |
9193 | ||
9194 | mutex_lock(&event_mutex); | |
9195 | mutex_lock(&trace_types_lock); | |
9196 | ||
9197 | ret = -ENODEV; | |
89c95fce TZ |
9198 | tr = trace_array_find(name); |
9199 | if (tr) | |
9200 | ret = __remove_instance(tr); | |
0c8916c3 | 9201 | |
0c8916c3 | 9202 | mutex_unlock(&trace_types_lock); |
12ecef0c | 9203 | mutex_unlock(&event_mutex); |
0c8916c3 SR |
9204 | |
9205 | return ret; | |
9206 | } | |
9207 | ||
277ba044 SR |
9208 | static __init void create_trace_instances(struct dentry *d_tracer) |
9209 | { | |
4114fbfd MH |
9210 | struct trace_array *tr; |
9211 | ||
eae47358 SRRH |
9212 | trace_instance_dir = tracefs_create_instance_dir("instances", d_tracer, |
9213 | instance_mkdir, | |
9214 | instance_rmdir); | |
24589e3a | 9215 | if (MEM_FAIL(!trace_instance_dir, "Failed to create instances directory\n")) |
277ba044 | 9216 | return; |
4114fbfd MH |
9217 | |
9218 | mutex_lock(&event_mutex); | |
9219 | mutex_lock(&trace_types_lock); | |
9220 | ||
9221 | list_for_each_entry(tr, &ftrace_trace_arrays, list) { | |
9222 | if (!tr->name) | |
9223 | continue; | |
9224 | if (MEM_FAIL(trace_array_create_dir(tr) < 0, | |
9225 | "Failed to create instance directory\n")) | |
9226 | break; | |
9227 | } | |
9228 | ||
9229 | mutex_unlock(&trace_types_lock); | |
9230 | mutex_unlock(&event_mutex); | |
277ba044 SR |
9231 | } |
9232 | ||
2b6080f2 | 9233 | static void |
8434dc93 | 9234 | init_tracer_tracefs(struct trace_array *tr, struct dentry *d_tracer) |
2b6080f2 | 9235 | { |
3dd80953 | 9236 | struct trace_event_file *file; |
121aaee7 | 9237 | int cpu; |
2b6080f2 | 9238 | |
607e2ea1 SRRH |
9239 | trace_create_file("available_tracers", 0444, d_tracer, |
9240 | tr, &show_traces_fops); | |
9241 | ||
9242 | trace_create_file("current_tracer", 0644, d_tracer, | |
9243 | tr, &set_tracer_fops); | |
9244 | ||
ccfe9e42 AL |
9245 | trace_create_file("tracing_cpumask", 0644, d_tracer, |
9246 | tr, &tracing_cpumask_fops); | |
9247 | ||
2b6080f2 SR |
9248 | trace_create_file("trace_options", 0644, d_tracer, |
9249 | tr, &tracing_iter_fops); | |
9250 | ||
9251 | trace_create_file("trace", 0644, d_tracer, | |
6484c71c | 9252 | tr, &tracing_fops); |
2b6080f2 SR |
9253 | |
9254 | trace_create_file("trace_pipe", 0444, d_tracer, | |
15544209 | 9255 | tr, &tracing_pipe_fops); |
2b6080f2 SR |
9256 | |
9257 | trace_create_file("buffer_size_kb", 0644, d_tracer, | |
0bc392ee | 9258 | tr, &tracing_entries_fops); |
2b6080f2 SR |
9259 | |
9260 | trace_create_file("buffer_total_size_kb", 0444, d_tracer, | |
9261 | tr, &tracing_total_entries_fops); | |
9262 | ||
238ae93d | 9263 | trace_create_file("free_buffer", 0200, d_tracer, |
2b6080f2 SR |
9264 | tr, &tracing_free_buffer_fops); |
9265 | ||
9266 | trace_create_file("trace_marker", 0220, d_tracer, | |
9267 | tr, &tracing_mark_fops); | |
9268 | ||
3dd80953 SRV |
9269 | file = __find_event_file(tr, "ftrace", "print"); |
9270 | if (file && file->dir) | |
9271 | trace_create_file("trigger", 0644, file->dir, file, | |
9272 | &event_trigger_fops); | |
9273 | tr->trace_marker_file = file; | |
9274 | ||
fa32e855 SR |
9275 | trace_create_file("trace_marker_raw", 0220, d_tracer, |
9276 | tr, &tracing_mark_raw_fops); | |
9277 | ||
2b6080f2 SR |
9278 | trace_create_file("trace_clock", 0644, d_tracer, tr, |
9279 | &trace_clock_fops); | |
9280 | ||
9281 | trace_create_file("tracing_on", 0644, d_tracer, | |
6484c71c | 9282 | tr, &rb_simple_fops); |
ce9bae55 | 9283 | |
2c1ea60b TZ |
9284 | trace_create_file("timestamp_mode", 0444, d_tracer, tr, |
9285 | &trace_time_stamp_mode_fops); | |
9286 | ||
a7b1d74e | 9287 | tr->buffer_percent = 50; |
03329f99 SRV |
9288 | |
9289 | trace_create_file("buffer_percent", 0444, d_tracer, | |
9290 | tr, &buffer_percent_fops); | |
9291 | ||
16270145 SRRH |
9292 | create_trace_options_dir(tr); |
9293 | ||
f971cc9a | 9294 | #if defined(CONFIG_TRACER_MAX_TRACE) || defined(CONFIG_HWLAT_TRACER) |
91edde2e | 9295 | trace_create_maxlat_file(tr, d_tracer); |
6d9b3fa5 SRRH |
9296 | #endif |
9297 | ||
591dffda | 9298 | if (ftrace_create_function_files(tr, d_tracer)) |
24589e3a | 9299 | MEM_FAIL(1, "Could not allocate function filter files"); |
591dffda | 9300 | |
ce9bae55 SRRH |
9301 | #ifdef CONFIG_TRACER_SNAPSHOT |
9302 | trace_create_file("snapshot", 0644, d_tracer, | |
6484c71c | 9303 | tr, &snapshot_fops); |
ce9bae55 | 9304 | #endif |
121aaee7 | 9305 | |
8a062902 TZ |
9306 | trace_create_file("error_log", 0644, d_tracer, |
9307 | tr, &tracing_err_log_fops); | |
9308 | ||
121aaee7 | 9309 | for_each_tracing_cpu(cpu) |
8434dc93 | 9310 | tracing_init_tracefs_percpu(tr, cpu); |
121aaee7 | 9311 | |
345ddcc8 | 9312 | ftrace_init_tracefs(tr, d_tracer); |
2b6080f2 SR |
9313 | } |
9314 | ||
93faccbb | 9315 | static struct vfsmount *trace_automount(struct dentry *mntpt, void *ingore) |
f76180bc SRRH |
9316 | { |
9317 | struct vfsmount *mnt; | |
9318 | struct file_system_type *type; | |
9319 | ||
9320 | /* | |
9321 | * To maintain backward compatibility for tools that mount | |
9322 | * debugfs to get to the tracing facility, tracefs is automatically | |
9323 | * mounted to the debugfs/tracing directory. | |
9324 | */ | |
9325 | type = get_fs_type("tracefs"); | |
9326 | if (!type) | |
9327 | return NULL; | |
93faccbb | 9328 | mnt = vfs_submount(mntpt, type, "tracefs", NULL); |
f76180bc SRRH |
9329 | put_filesystem(type); |
9330 | if (IS_ERR(mnt)) | |
9331 | return NULL; | |
9332 | mntget(mnt); | |
9333 | ||
9334 | return mnt; | |
9335 | } | |
9336 | ||
7eeafbca SRRH |
9337 | /** |
9338 | * tracing_init_dentry - initialize top level trace array | |
9339 | * | |
9340 | * This is called when creating files or directories in the tracing | |
9341 | * directory. It is called via fs_initcall() by any of the boot up code | |
9342 | * and expects to return the dentry of the top level tracing directory. | |
9343 | */ | |
22c36b18 | 9344 | int tracing_init_dentry(void) |
7eeafbca SRRH |
9345 | { |
9346 | struct trace_array *tr = &global_trace; | |
9347 | ||
a356646a | 9348 | if (security_locked_down(LOCKDOWN_TRACEFS)) { |
ee195452 | 9349 | pr_warn("Tracing disabled due to lockdown\n"); |
22c36b18 | 9350 | return -EPERM; |
a356646a SRV |
9351 | } |
9352 | ||
f76180bc | 9353 | /* The top level trace array uses NULL as parent */ |
7eeafbca | 9354 | if (tr->dir) |
22c36b18 | 9355 | return 0; |
7eeafbca | 9356 | |
072e133d | 9357 | if (WARN_ON(!tracefs_initialized())) |
22c36b18 | 9358 | return -ENODEV; |
7eeafbca | 9359 | |
f76180bc SRRH |
9360 | /* |
9361 | * As there may still be users that expect the tracing | |
9362 | * files to exist in debugfs/tracing, we must automount | |
9363 | * the tracefs file system there, so older tools still | |
f2cc020d | 9364 | * work with the newer kernel. |
f76180bc SRRH |
9365 | */ |
9366 | tr->dir = debugfs_create_automount("tracing", NULL, | |
9367 | trace_automount, NULL); | |
7eeafbca | 9368 | |
22c36b18 | 9369 | return 0; |
7eeafbca SRRH |
9370 | } |
9371 | ||
00f4b652 JL |
9372 | extern struct trace_eval_map *__start_ftrace_eval_maps[]; |
9373 | extern struct trace_eval_map *__stop_ftrace_eval_maps[]; | |
0c564a53 | 9374 | |
f6a69466 SRV |
9375 | static struct workqueue_struct *eval_map_wq __initdata; |
9376 | static struct work_struct eval_map_work __initdata; | |
9377 | ||
9378 | static void __init eval_map_work_func(struct work_struct *work) | |
0c564a53 | 9379 | { |
3673b8e4 SRRH |
9380 | int len; |
9381 | ||
02fd7f68 | 9382 | len = __stop_ftrace_eval_maps - __start_ftrace_eval_maps; |
f57a4143 | 9383 | trace_insert_eval_map(NULL, __start_ftrace_eval_maps, len); |
3673b8e4 SRRH |
9384 | } |
9385 | ||
f6a69466 SRV |
9386 | static int __init trace_eval_init(void) |
9387 | { | |
9388 | INIT_WORK(&eval_map_work, eval_map_work_func); | |
9389 | ||
9390 | eval_map_wq = alloc_workqueue("eval_map_wq", WQ_UNBOUND, 0); | |
9391 | if (!eval_map_wq) { | |
9392 | pr_err("Unable to allocate eval_map_wq\n"); | |
9393 | /* Do work here */ | |
9394 | eval_map_work_func(&eval_map_work); | |
9395 | return -ENOMEM; | |
9396 | } | |
9397 | ||
9398 | queue_work(eval_map_wq, &eval_map_work); | |
9399 | return 0; | |
9400 | } | |
9401 | ||
9402 | static int __init trace_eval_sync(void) | |
9403 | { | |
9404 | /* Make sure the eval map updates are finished */ | |
9405 | if (eval_map_wq) | |
9406 | destroy_workqueue(eval_map_wq); | |
9407 | return 0; | |
9408 | } | |
9409 | ||
9410 | late_initcall_sync(trace_eval_sync); | |
9411 | ||
9412 | ||
3673b8e4 | 9413 | #ifdef CONFIG_MODULES |
f57a4143 | 9414 | static void trace_module_add_evals(struct module *mod) |
3673b8e4 | 9415 | { |
99be647c | 9416 | if (!mod->num_trace_evals) |
3673b8e4 SRRH |
9417 | return; |
9418 | ||
9419 | /* | |
9420 | * Modules with bad taint do not have events created, do | |
9421 | * not bother with enums either. | |
9422 | */ | |
9423 | if (trace_module_has_bad_taint(mod)) | |
9424 | return; | |
9425 | ||
f57a4143 | 9426 | trace_insert_eval_map(mod, mod->trace_evals, mod->num_trace_evals); |
3673b8e4 SRRH |
9427 | } |
9428 | ||
681bec03 | 9429 | #ifdef CONFIG_TRACE_EVAL_MAP_FILE |
f57a4143 | 9430 | static void trace_module_remove_evals(struct module *mod) |
9828413d | 9431 | { |
23bf8cb8 JL |
9432 | union trace_eval_map_item *map; |
9433 | union trace_eval_map_item **last = &trace_eval_maps; | |
9828413d | 9434 | |
99be647c | 9435 | if (!mod->num_trace_evals) |
9828413d SRRH |
9436 | return; |
9437 | ||
1793ed93 | 9438 | mutex_lock(&trace_eval_mutex); |
9828413d | 9439 | |
23bf8cb8 | 9440 | map = trace_eval_maps; |
9828413d SRRH |
9441 | |
9442 | while (map) { | |
9443 | if (map->head.mod == mod) | |
9444 | break; | |
5f60b351 | 9445 | map = trace_eval_jmp_to_tail(map); |
9828413d SRRH |
9446 | last = &map->tail.next; |
9447 | map = map->tail.next; | |
9448 | } | |
9449 | if (!map) | |
9450 | goto out; | |
9451 | ||
5f60b351 | 9452 | *last = trace_eval_jmp_to_tail(map)->tail.next; |
9828413d SRRH |
9453 | kfree(map); |
9454 | out: | |
1793ed93 | 9455 | mutex_unlock(&trace_eval_mutex); |
9828413d SRRH |
9456 | } |
9457 | #else | |
f57a4143 | 9458 | static inline void trace_module_remove_evals(struct module *mod) { } |
681bec03 | 9459 | #endif /* CONFIG_TRACE_EVAL_MAP_FILE */ |
9828413d | 9460 | |
3673b8e4 SRRH |
9461 | static int trace_module_notify(struct notifier_block *self, |
9462 | unsigned long val, void *data) | |
9463 | { | |
9464 | struct module *mod = data; | |
9465 | ||
9466 | switch (val) { | |
9467 | case MODULE_STATE_COMING: | |
f57a4143 | 9468 | trace_module_add_evals(mod); |
3673b8e4 | 9469 | break; |
9828413d | 9470 | case MODULE_STATE_GOING: |
f57a4143 | 9471 | trace_module_remove_evals(mod); |
9828413d | 9472 | break; |
3673b8e4 SRRH |
9473 | } |
9474 | ||
0340a6b7 | 9475 | return NOTIFY_OK; |
0c564a53 SRRH |
9476 | } |
9477 | ||
3673b8e4 SRRH |
9478 | static struct notifier_block trace_module_nb = { |
9479 | .notifier_call = trace_module_notify, | |
9480 | .priority = 0, | |
9481 | }; | |
9828413d | 9482 | #endif /* CONFIG_MODULES */ |
3673b8e4 | 9483 | |
8434dc93 | 9484 | static __init int tracer_init_tracefs(void) |
bc0c38d1 | 9485 | { |
22c36b18 | 9486 | int ret; |
bc0c38d1 | 9487 | |
7e53bd42 LJ |
9488 | trace_access_lock_init(); |
9489 | ||
22c36b18 WY |
9490 | ret = tracing_init_dentry(); |
9491 | if (ret) | |
ed6f1c99 | 9492 | return 0; |
bc0c38d1 | 9493 | |
58b92547 SRV |
9494 | event_trace_init(); |
9495 | ||
22c36b18 WY |
9496 | init_tracer_tracefs(&global_trace, NULL); |
9497 | ftrace_init_tracefs_toplevel(&global_trace, NULL); | |
bc0c38d1 | 9498 | |
22c36b18 | 9499 | trace_create_file("tracing_thresh", 0644, NULL, |
6508fa76 | 9500 | &global_trace, &tracing_thresh_fops); |
a8259075 | 9501 | |
22c36b18 | 9502 | trace_create_file("README", 0444, NULL, |
5452af66 FW |
9503 | NULL, &tracing_readme_fops); |
9504 | ||
22c36b18 | 9505 | trace_create_file("saved_cmdlines", 0444, NULL, |
69abe6a5 | 9506 | NULL, &tracing_saved_cmdlines_fops); |
5bf9a1ee | 9507 | |
22c36b18 | 9508 | trace_create_file("saved_cmdlines_size", 0644, NULL, |
939c7a4f YY |
9509 | NULL, &tracing_saved_cmdlines_size_fops); |
9510 | ||
22c36b18 | 9511 | trace_create_file("saved_tgids", 0444, NULL, |
99c621d7 MS |
9512 | NULL, &tracing_saved_tgids_fops); |
9513 | ||
5f60b351 | 9514 | trace_eval_init(); |
0c564a53 | 9515 | |
22c36b18 | 9516 | trace_create_eval_file(NULL); |
9828413d | 9517 | |
3673b8e4 SRRH |
9518 | #ifdef CONFIG_MODULES |
9519 | register_module_notifier(&trace_module_nb); | |
9520 | #endif | |
9521 | ||
bc0c38d1 | 9522 | #ifdef CONFIG_DYNAMIC_FTRACE |
22c36b18 | 9523 | trace_create_file("dyn_ftrace_total_info", 0444, NULL, |
da537f0a | 9524 | NULL, &tracing_dyn_info_fops); |
bc0c38d1 | 9525 | #endif |
b04cc6b1 | 9526 | |
22c36b18 | 9527 | create_trace_instances(NULL); |
5452af66 | 9528 | |
37aea98b | 9529 | update_tracer_options(&global_trace); |
09d23a1d | 9530 | |
b5ad384e | 9531 | return 0; |
bc0c38d1 SR |
9532 | } |
9533 | ||
3f5a54e3 SR |
9534 | static int trace_panic_handler(struct notifier_block *this, |
9535 | unsigned long event, void *unused) | |
9536 | { | |
944ac425 | 9537 | if (ftrace_dump_on_oops) |
cecbca96 | 9538 | ftrace_dump(ftrace_dump_on_oops); |
3f5a54e3 SR |
9539 | return NOTIFY_OK; |
9540 | } | |
9541 | ||
9542 | static struct notifier_block trace_panic_notifier = { | |
9543 | .notifier_call = trace_panic_handler, | |
9544 | .next = NULL, | |
9545 | .priority = 150 /* priority: INT_MAX >= x >= 0 */ | |
9546 | }; | |
9547 | ||
9548 | static int trace_die_handler(struct notifier_block *self, | |
9549 | unsigned long val, | |
9550 | void *data) | |
9551 | { | |
9552 | switch (val) { | |
9553 | case DIE_OOPS: | |
944ac425 | 9554 | if (ftrace_dump_on_oops) |
cecbca96 | 9555 | ftrace_dump(ftrace_dump_on_oops); |
3f5a54e3 SR |
9556 | break; |
9557 | default: | |
9558 | break; | |
9559 | } | |
9560 | return NOTIFY_OK; | |
9561 | } | |
9562 | ||
9563 | static struct notifier_block trace_die_notifier = { | |
9564 | .notifier_call = trace_die_handler, | |
9565 | .priority = 200 | |
9566 | }; | |
9567 | ||
9568 | /* | |
9569 | * printk is set to max of 1024, we really don't need it that big. | |
9570 | * Nothing should be printing 1000 characters anyway. | |
9571 | */ | |
9572 | #define TRACE_MAX_PRINT 1000 | |
9573 | ||
9574 | /* | |
9575 | * Define here KERN_TRACE so that we have one place to modify | |
9576 | * it if we decide to change what log level the ftrace dump | |
9577 | * should be at. | |
9578 | */ | |
428aee14 | 9579 | #define KERN_TRACE KERN_EMERG |
3f5a54e3 | 9580 | |
955b61e5 | 9581 | void |
3f5a54e3 SR |
9582 | trace_printk_seq(struct trace_seq *s) |
9583 | { | |
9584 | /* Probably should print a warning here. */ | |
3a161d99 SRRH |
9585 | if (s->seq.len >= TRACE_MAX_PRINT) |
9586 | s->seq.len = TRACE_MAX_PRINT; | |
3f5a54e3 | 9587 | |
820b75f6 SRRH |
9588 | /* |
9589 | * More paranoid code. Although the buffer size is set to | |
9590 | * PAGE_SIZE, and TRACE_MAX_PRINT is 1000, this is just | |
9591 | * an extra layer of protection. | |
9592 | */ | |
9593 | if (WARN_ON_ONCE(s->seq.len >= s->seq.size)) | |
9594 | s->seq.len = s->seq.size - 1; | |
3f5a54e3 SR |
9595 | |
9596 | /* should be zero ended, but we are paranoid. */ | |
3a161d99 | 9597 | s->buffer[s->seq.len] = 0; |
3f5a54e3 SR |
9598 | |
9599 | printk(KERN_TRACE "%s", s->buffer); | |
9600 | ||
f9520750 | 9601 | trace_seq_init(s); |
3f5a54e3 SR |
9602 | } |
9603 | ||
955b61e5 JW |
9604 | void trace_init_global_iter(struct trace_iterator *iter) |
9605 | { | |
9606 | iter->tr = &global_trace; | |
2b6080f2 | 9607 | iter->trace = iter->tr->current_trace; |
ae3b5093 | 9608 | iter->cpu_file = RING_BUFFER_ALL_CPUS; |
1c5eb448 | 9609 | iter->array_buffer = &global_trace.array_buffer; |
b2f974d6 CS |
9610 | |
9611 | if (iter->trace && iter->trace->open) | |
9612 | iter->trace->open(iter); | |
9613 | ||
9614 | /* Annotate start of buffers if we had overruns */ | |
1c5eb448 | 9615 | if (ring_buffer_overruns(iter->array_buffer->buffer)) |
b2f974d6 CS |
9616 | iter->iter_flags |= TRACE_FILE_ANNOTATE; |
9617 | ||
9618 | /* Output in nanoseconds only if we are using a clock in nanoseconds. */ | |
9619 | if (trace_clocks[iter->tr->clock_id].in_ns) | |
9620 | iter->iter_flags |= TRACE_FILE_TIME_IN_NS; | |
955b61e5 JW |
9621 | } |
9622 | ||
7fe70b57 | 9623 | void ftrace_dump(enum ftrace_dump_mode oops_dump_mode) |
3f5a54e3 | 9624 | { |
3f5a54e3 SR |
9625 | /* use static because iter can be a bit big for the stack */ |
9626 | static struct trace_iterator iter; | |
7fe70b57 | 9627 | static atomic_t dump_running; |
983f938a | 9628 | struct trace_array *tr = &global_trace; |
cf586b61 | 9629 | unsigned int old_userobj; |
d769041f SR |
9630 | unsigned long flags; |
9631 | int cnt = 0, cpu; | |
3f5a54e3 | 9632 | |
7fe70b57 SRRH |
9633 | /* Only allow one dump user at a time. */ |
9634 | if (atomic_inc_return(&dump_running) != 1) { | |
9635 | atomic_dec(&dump_running); | |
9636 | return; | |
9637 | } | |
3f5a54e3 | 9638 | |
7fe70b57 SRRH |
9639 | /* |
9640 | * Always turn off tracing when we dump. | |
9641 | * We don't need to show trace output of what happens | |
9642 | * between multiple crashes. | |
9643 | * | |
9644 | * If the user does a sysrq-z, then they can re-enable | |
9645 | * tracing with echo 1 > tracing_on. | |
9646 | */ | |
0ee6b6cf | 9647 | tracing_off(); |
cf586b61 | 9648 | |
7fe70b57 | 9649 | local_irq_save(flags); |
03fc7f9c | 9650 | printk_nmi_direct_enter(); |
3f5a54e3 | 9651 | |
38dbe0b1 | 9652 | /* Simulate the iterator */ |
955b61e5 | 9653 | trace_init_global_iter(&iter); |
efbbdaa2 | 9654 | /* Can not use kmalloc for iter.temp and iter.fmt */ |
8e99cf91 SRV |
9655 | iter.temp = static_temp_buf; |
9656 | iter.temp_size = STATIC_TEMP_BUF_SIZE; | |
efbbdaa2 MH |
9657 | iter.fmt = static_fmt_buf; |
9658 | iter.fmt_size = STATIC_FMT_BUF_SIZE; | |
955b61e5 | 9659 | |
d769041f | 9660 | for_each_tracing_cpu(cpu) { |
1c5eb448 | 9661 | atomic_inc(&per_cpu_ptr(iter.array_buffer->data, cpu)->disabled); |
d769041f SR |
9662 | } |
9663 | ||
983f938a | 9664 | old_userobj = tr->trace_flags & TRACE_ITER_SYM_USEROBJ; |
cf586b61 | 9665 | |
b54d3de9 | 9666 | /* don't look at user memory in panic mode */ |
983f938a | 9667 | tr->trace_flags &= ~TRACE_ITER_SYM_USEROBJ; |
b54d3de9 | 9668 | |
cecbca96 FW |
9669 | switch (oops_dump_mode) { |
9670 | case DUMP_ALL: | |
ae3b5093 | 9671 | iter.cpu_file = RING_BUFFER_ALL_CPUS; |
cecbca96 FW |
9672 | break; |
9673 | case DUMP_ORIG: | |
9674 | iter.cpu_file = raw_smp_processor_id(); | |
9675 | break; | |
9676 | case DUMP_NONE: | |
9677 | goto out_enable; | |
9678 | default: | |
9679 | printk(KERN_TRACE "Bad dumping mode, switching to all CPUs dump\n"); | |
ae3b5093 | 9680 | iter.cpu_file = RING_BUFFER_ALL_CPUS; |
cecbca96 FW |
9681 | } |
9682 | ||
9683 | printk(KERN_TRACE "Dumping ftrace buffer:\n"); | |
3f5a54e3 | 9684 | |
7fe70b57 SRRH |
9685 | /* Did function tracer already get disabled? */ |
9686 | if (ftrace_is_dead()) { | |
9687 | printk("# WARNING: FUNCTION TRACING IS CORRUPTED\n"); | |
9688 | printk("# MAY BE MISSING FUNCTION EVENTS\n"); | |
9689 | } | |
9690 | ||
3f5a54e3 | 9691 | /* |
5c8c206e | 9692 | * We need to stop all tracing on all CPUS to read |
3f5a54e3 SR |
9693 | * the next buffer. This is a bit expensive, but is |
9694 | * not done often. We fill all what we can read, | |
9695 | * and then release the locks again. | |
9696 | */ | |
9697 | ||
3f5a54e3 SR |
9698 | while (!trace_empty(&iter)) { |
9699 | ||
9700 | if (!cnt) | |
9701 | printk(KERN_TRACE "---------------------------------\n"); | |
9702 | ||
9703 | cnt++; | |
9704 | ||
0c97bf86 | 9705 | trace_iterator_reset(&iter); |
3f5a54e3 | 9706 | iter.iter_flags |= TRACE_FILE_LAT_FMT; |
3f5a54e3 | 9707 | |
955b61e5 | 9708 | if (trace_find_next_entry_inc(&iter) != NULL) { |
74e7ff8c LJ |
9709 | int ret; |
9710 | ||
9711 | ret = print_trace_line(&iter); | |
9712 | if (ret != TRACE_TYPE_NO_CONSUME) | |
9713 | trace_consume(&iter); | |
3f5a54e3 | 9714 | } |
b892e5c8 | 9715 | touch_nmi_watchdog(); |
3f5a54e3 SR |
9716 | |
9717 | trace_printk_seq(&iter.seq); | |
9718 | } | |
9719 | ||
9720 | if (!cnt) | |
9721 | printk(KERN_TRACE " (ftrace buffer empty)\n"); | |
9722 | else | |
9723 | printk(KERN_TRACE "---------------------------------\n"); | |
9724 | ||
cecbca96 | 9725 | out_enable: |
983f938a | 9726 | tr->trace_flags |= old_userobj; |
cf586b61 | 9727 | |
7fe70b57 | 9728 | for_each_tracing_cpu(cpu) { |
1c5eb448 | 9729 | atomic_dec(&per_cpu_ptr(iter.array_buffer->data, cpu)->disabled); |
cf586b61 | 9730 | } |
03fc7f9c PM |
9731 | atomic_dec(&dump_running); |
9732 | printk_nmi_direct_exit(); | |
cd891ae0 | 9733 | local_irq_restore(flags); |
3f5a54e3 | 9734 | } |
a8eecf22 | 9735 | EXPORT_SYMBOL_GPL(ftrace_dump); |
cf586b61 | 9736 | |
7e465baa TZ |
9737 | #define WRITE_BUFSIZE 4096 |
9738 | ||
9739 | ssize_t trace_parse_run_command(struct file *file, const char __user *buffer, | |
9740 | size_t count, loff_t *ppos, | |
d262271d | 9741 | int (*createfn)(const char *)) |
7e465baa TZ |
9742 | { |
9743 | char *kbuf, *buf, *tmp; | |
9744 | int ret = 0; | |
9745 | size_t done = 0; | |
9746 | size_t size; | |
9747 | ||
9748 | kbuf = kmalloc(WRITE_BUFSIZE, GFP_KERNEL); | |
9749 | if (!kbuf) | |
9750 | return -ENOMEM; | |
9751 | ||
9752 | while (done < count) { | |
9753 | size = count - done; | |
9754 | ||
9755 | if (size >= WRITE_BUFSIZE) | |
9756 | size = WRITE_BUFSIZE - 1; | |
9757 | ||
9758 | if (copy_from_user(kbuf, buffer + done, size)) { | |
9759 | ret = -EFAULT; | |
9760 | goto out; | |
9761 | } | |
9762 | kbuf[size] = '\0'; | |
9763 | buf = kbuf; | |
9764 | do { | |
9765 | tmp = strchr(buf, '\n'); | |
9766 | if (tmp) { | |
9767 | *tmp = '\0'; | |
9768 | size = tmp - buf + 1; | |
9769 | } else { | |
9770 | size = strlen(buf); | |
9771 | if (done + size < count) { | |
9772 | if (buf != kbuf) | |
9773 | break; | |
9774 | /* This can accept WRITE_BUFSIZE - 2 ('\n' + '\0') */ | |
9775 | pr_warn("Line length is too long: Should be less than %d\n", | |
9776 | WRITE_BUFSIZE - 2); | |
9777 | ret = -EINVAL; | |
9778 | goto out; | |
9779 | } | |
9780 | } | |
9781 | done += size; | |
9782 | ||
9783 | /* Remove comments */ | |
9784 | tmp = strchr(buf, '#'); | |
9785 | ||
9786 | if (tmp) | |
9787 | *tmp = '\0'; | |
9788 | ||
d262271d | 9789 | ret = createfn(buf); |
7e465baa TZ |
9790 | if (ret) |
9791 | goto out; | |
9792 | buf += size; | |
9793 | ||
9794 | } while (done < count); | |
9795 | } | |
9796 | ret = done; | |
9797 | ||
9798 | out: | |
9799 | kfree(kbuf); | |
9800 | ||
9801 | return ret; | |
9802 | } | |
9803 | ||
3928a8a2 | 9804 | __init static int tracer_alloc_buffers(void) |
bc0c38d1 | 9805 | { |
73c5162a | 9806 | int ring_buf_size; |
9e01c1b7 | 9807 | int ret = -ENOMEM; |
4c11d7ae | 9808 | |
a356646a SRV |
9809 | |
9810 | if (security_locked_down(LOCKDOWN_TRACEFS)) { | |
ee195452 | 9811 | pr_warn("Tracing disabled due to lockdown\n"); |
a356646a SRV |
9812 | return -EPERM; |
9813 | } | |
9814 | ||
b5e87c05 | 9815 | /* |
499f7bb0 | 9816 | * Make sure we don't accidentally add more trace options |
b5e87c05 SRRH |
9817 | * than we have bits for. |
9818 | */ | |
9a38a885 | 9819 | BUILD_BUG_ON(TRACE_ITER_LAST_BIT > TRACE_FLAGS_MAX_SIZE); |
b5e87c05 | 9820 | |
9e01c1b7 RR |
9821 | if (!alloc_cpumask_var(&tracing_buffer_mask, GFP_KERNEL)) |
9822 | goto out; | |
9823 | ||
ccfe9e42 | 9824 | if (!alloc_cpumask_var(&global_trace.tracing_cpumask, GFP_KERNEL)) |
9e01c1b7 | 9825 | goto out_free_buffer_mask; |
4c11d7ae | 9826 | |
07d777fe | 9827 | /* Only allocate trace_printk buffers if a trace_printk exists */ |
bf2cbe04 | 9828 | if (&__stop___trace_bprintk_fmt != &__start___trace_bprintk_fmt) |
81698831 | 9829 | /* Must be called before global_trace.buffer is allocated */ |
07d777fe SR |
9830 | trace_printk_init_buffers(); |
9831 | ||
73c5162a SR |
9832 | /* To save memory, keep the ring buffer size to its minimum */ |
9833 | if (ring_buffer_expanded) | |
9834 | ring_buf_size = trace_buf_size; | |
9835 | else | |
9836 | ring_buf_size = 1; | |
9837 | ||
9e01c1b7 | 9838 | cpumask_copy(tracing_buffer_mask, cpu_possible_mask); |
ccfe9e42 | 9839 | cpumask_copy(global_trace.tracing_cpumask, cpu_all_mask); |
9e01c1b7 | 9840 | |
2b6080f2 SR |
9841 | raw_spin_lock_init(&global_trace.start_lock); |
9842 | ||
b32614c0 SAS |
9843 | /* |
9844 | * The prepare callbacks allocates some memory for the ring buffer. We | |
499f7bb0 | 9845 | * don't free the buffer if the CPU goes down. If we were to free |
b32614c0 SAS |
9846 | * the buffer, then the user would lose any trace that was in the |
9847 | * buffer. The memory will be removed once the "instance" is removed. | |
9848 | */ | |
9849 | ret = cpuhp_setup_state_multi(CPUHP_TRACE_RB_PREPARE, | |
9850 | "trace/RB:preapre", trace_rb_cpu_prepare, | |
9851 | NULL); | |
9852 | if (ret < 0) | |
9853 | goto out_free_cpumask; | |
2c4a33ab | 9854 | /* Used for event triggers */ |
147d88e0 | 9855 | ret = -ENOMEM; |
2c4a33ab SRRH |
9856 | temp_buffer = ring_buffer_alloc(PAGE_SIZE, RB_FL_OVERWRITE); |
9857 | if (!temp_buffer) | |
b32614c0 | 9858 | goto out_rm_hp_state; |
2c4a33ab | 9859 | |
939c7a4f YY |
9860 | if (trace_create_savedcmd() < 0) |
9861 | goto out_free_temp_buffer; | |
9862 | ||
9e01c1b7 | 9863 | /* TODO: make the number of buffers hot pluggable with CPUS */ |
737223fb | 9864 | if (allocate_trace_buffers(&global_trace, ring_buf_size) < 0) { |
24589e3a | 9865 | MEM_FAIL(1, "tracer: failed to allocate ring buffer!\n"); |
939c7a4f | 9866 | goto out_free_savedcmd; |
4c11d7ae | 9867 | } |
a7603ff4 | 9868 | |
499e5470 SR |
9869 | if (global_trace.buffer_disabled) |
9870 | tracing_off(); | |
4c11d7ae | 9871 | |
e1e232ca SR |
9872 | if (trace_boot_clock) { |
9873 | ret = tracing_set_clock(&global_trace, trace_boot_clock); | |
9874 | if (ret < 0) | |
a395d6a7 JP |
9875 | pr_warn("Trace clock %s not defined, going back to default\n", |
9876 | trace_boot_clock); | |
e1e232ca SR |
9877 | } |
9878 | ||
ca164318 SRRH |
9879 | /* |
9880 | * register_tracer() might reference current_trace, so it | |
9881 | * needs to be set before we register anything. This is | |
9882 | * just a bootstrap of current_trace anyway. | |
9883 | */ | |
2b6080f2 SR |
9884 | global_trace.current_trace = &nop_trace; |
9885 | ||
0b9b12c1 SRRH |
9886 | global_trace.max_lock = (arch_spinlock_t)__ARCH_SPIN_LOCK_UNLOCKED; |
9887 | ||
4104d326 SRRH |
9888 | ftrace_init_global_array_ops(&global_trace); |
9889 | ||
9a38a885 SRRH |
9890 | init_trace_flags_index(&global_trace); |
9891 | ||
ca164318 SRRH |
9892 | register_tracer(&nop_trace); |
9893 | ||
dbeafd0d SRV |
9894 | /* Function tracing may start here (via kernel command line) */ |
9895 | init_function_trace(); | |
9896 | ||
60a11774 SR |
9897 | /* All seems OK, enable tracing */ |
9898 | tracing_disabled = 0; | |
3928a8a2 | 9899 | |
3f5a54e3 SR |
9900 | atomic_notifier_chain_register(&panic_notifier_list, |
9901 | &trace_panic_notifier); | |
9902 | ||
9903 | register_die_notifier(&trace_die_notifier); | |
2fc1dfbe | 9904 | |
ae63b31e SR |
9905 | global_trace.flags = TRACE_ARRAY_FL_GLOBAL; |
9906 | ||
9907 | INIT_LIST_HEAD(&global_trace.systems); | |
9908 | INIT_LIST_HEAD(&global_trace.events); | |
067fe038 | 9909 | INIT_LIST_HEAD(&global_trace.hist_vars); |
2f754e77 | 9910 | INIT_LIST_HEAD(&global_trace.err_log); |
ae63b31e SR |
9911 | list_add(&global_trace.list, &ftrace_trace_arrays); |
9912 | ||
a4d1e688 | 9913 | apply_trace_boot_options(); |
7bcfaf54 | 9914 | |
77fd5c15 SRRH |
9915 | register_snapshot_cmd(); |
9916 | ||
9a6944fe SRV |
9917 | test_can_verify(); |
9918 | ||
2fc1dfbe | 9919 | return 0; |
3f5a54e3 | 9920 | |
939c7a4f YY |
9921 | out_free_savedcmd: |
9922 | free_saved_cmdlines_buffer(savedcmd); | |
2c4a33ab SRRH |
9923 | out_free_temp_buffer: |
9924 | ring_buffer_free(temp_buffer); | |
b32614c0 SAS |
9925 | out_rm_hp_state: |
9926 | cpuhp_remove_multi_state(CPUHP_TRACE_RB_PREPARE); | |
9e01c1b7 | 9927 | out_free_cpumask: |
ccfe9e42 | 9928 | free_cpumask_var(global_trace.tracing_cpumask); |
9e01c1b7 RR |
9929 | out_free_buffer_mask: |
9930 | free_cpumask_var(tracing_buffer_mask); | |
9931 | out: | |
9932 | return ret; | |
bc0c38d1 | 9933 | } |
b2821ae6 | 9934 | |
e725c731 | 9935 | void __init early_trace_init(void) |
5f893b26 | 9936 | { |
0daa2302 SRRH |
9937 | if (tracepoint_printk) { |
9938 | tracepoint_print_iter = | |
0e1e71d3 | 9939 | kzalloc(sizeof(*tracepoint_print_iter), GFP_KERNEL); |
24589e3a SRV |
9940 | if (MEM_FAIL(!tracepoint_print_iter, |
9941 | "Failed to allocate trace iterator\n")) | |
0daa2302 | 9942 | tracepoint_printk = 0; |
42391745 SRRH |
9943 | else |
9944 | static_key_enable(&tracepoint_printk_key.key); | |
0daa2302 | 9945 | } |
5f893b26 | 9946 | tracer_alloc_buffers(); |
e725c731 SRV |
9947 | } |
9948 | ||
9949 | void __init trace_init(void) | |
9950 | { | |
0c564a53 | 9951 | trace_event_init(); |
5f893b26 SRRH |
9952 | } |
9953 | ||
b2821ae6 SR |
9954 | __init static int clear_boot_tracer(void) |
9955 | { | |
9956 | /* | |
9957 | * The default tracer at boot buffer is an init section. | |
9958 | * This function is called in lateinit. If we did not | |
9959 | * find the boot tracer, then clear it out, to prevent | |
9960 | * later registration from accessing the buffer that is | |
9961 | * about to be freed. | |
9962 | */ | |
9963 | if (!default_bootup_tracer) | |
9964 | return 0; | |
9965 | ||
9966 | printk(KERN_INFO "ftrace bootup tracer '%s' not registered.\n", | |
9967 | default_bootup_tracer); | |
9968 | default_bootup_tracer = NULL; | |
9969 | ||
9970 | return 0; | |
9971 | } | |
9972 | ||
8434dc93 | 9973 | fs_initcall(tracer_init_tracefs); |
4bb0f0e7 | 9974 | late_initcall_sync(clear_boot_tracer); |
3fd49c9e CW |
9975 | |
9976 | #ifdef CONFIG_HAVE_UNSTABLE_SCHED_CLOCK | |
9977 | __init static int tracing_set_default_clock(void) | |
9978 | { | |
9979 | /* sched_clock_stable() is determined in late_initcall */ | |
5125eee4 | 9980 | if (!trace_boot_clock && !sched_clock_stable()) { |
bf24daac MI |
9981 | if (security_locked_down(LOCKDOWN_TRACEFS)) { |
9982 | pr_warn("Can not set tracing clock due to lockdown\n"); | |
9983 | return -EPERM; | |
9984 | } | |
9985 | ||
3fd49c9e CW |
9986 | printk(KERN_WARNING |
9987 | "Unstable clock detected, switching default tracing clock to \"global\"\n" | |
9988 | "If you want to keep using the local clock, then add:\n" | |
9989 | " \"trace_clock=local\"\n" | |
9990 | "on the kernel command line\n"); | |
9991 | tracing_set_clock(&global_trace, "global"); | |
9992 | } | |
9993 | ||
9994 | return 0; | |
9995 | } | |
9996 | late_initcall_sync(tracing_set_default_clock); | |
9997 | #endif |