Commit | Line | Data |
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bc0c38d1 SR |
1 | /* |
2 | * ring buffer based function tracer | |
3 | * | |
2b6080f2 | 4 | * Copyright (C) 2007-2012 Steven Rostedt <srostedt@redhat.com> |
bc0c38d1 SR |
5 | * Copyright (C) 2008 Ingo Molnar <mingo@redhat.com> |
6 | * | |
7 | * Originally taken from the RT patch by: | |
8 | * Arnaldo Carvalho de Melo <acme@redhat.com> | |
9 | * | |
10 | * Based on code from the latency_tracer, that is: | |
11 | * Copyright (C) 2004-2006 Ingo Molnar | |
6d49e352 | 12 | * Copyright (C) 2004 Nadia Yvette Chambers |
bc0c38d1 | 13 | */ |
2cadf913 | 14 | #include <linux/ring_buffer.h> |
273b281f | 15 | #include <generated/utsrelease.h> |
2cadf913 SR |
16 | #include <linux/stacktrace.h> |
17 | #include <linux/writeback.h> | |
bc0c38d1 SR |
18 | #include <linux/kallsyms.h> |
19 | #include <linux/seq_file.h> | |
3f5a54e3 | 20 | #include <linux/notifier.h> |
2cadf913 | 21 | #include <linux/irqflags.h> |
bc0c38d1 | 22 | #include <linux/debugfs.h> |
8434dc93 | 23 | #include <linux/tracefs.h> |
4c11d7ae | 24 | #include <linux/pagemap.h> |
bc0c38d1 SR |
25 | #include <linux/hardirq.h> |
26 | #include <linux/linkage.h> | |
27 | #include <linux/uaccess.h> | |
76c813e2 | 28 | #include <linux/vmalloc.h> |
bc0c38d1 SR |
29 | #include <linux/ftrace.h> |
30 | #include <linux/module.h> | |
31 | #include <linux/percpu.h> | |
2cadf913 | 32 | #include <linux/splice.h> |
3f5a54e3 | 33 | #include <linux/kdebug.h> |
5f0c6c03 | 34 | #include <linux/string.h> |
f76180bc | 35 | #include <linux/mount.h> |
7e53bd42 | 36 | #include <linux/rwsem.h> |
5a0e3ad6 | 37 | #include <linux/slab.h> |
bc0c38d1 SR |
38 | #include <linux/ctype.h> |
39 | #include <linux/init.h> | |
2a2cc8f7 | 40 | #include <linux/poll.h> |
b892e5c8 | 41 | #include <linux/nmi.h> |
bc0c38d1 | 42 | #include <linux/fs.h> |
8bd75c77 | 43 | #include <linux/sched/rt.h> |
86387f7e | 44 | |
bc0c38d1 | 45 | #include "trace.h" |
f0868d1e | 46 | #include "trace_output.h" |
bc0c38d1 | 47 | |
73c5162a SR |
48 | /* |
49 | * On boot up, the ring buffer is set to the minimum size, so that | |
50 | * we do not waste memory on systems that are not using tracing. | |
51 | */ | |
55034cd6 | 52 | bool ring_buffer_expanded; |
73c5162a | 53 | |
8e1b82e0 FW |
54 | /* |
55 | * We need to change this state when a selftest is running. | |
ff32504f FW |
56 | * A selftest will lurk into the ring-buffer to count the |
57 | * entries inserted during the selftest although some concurrent | |
5e1607a0 | 58 | * insertions into the ring-buffer such as trace_printk could occurred |
ff32504f FW |
59 | * at the same time, giving false positive or negative results. |
60 | */ | |
8e1b82e0 | 61 | static bool __read_mostly tracing_selftest_running; |
ff32504f | 62 | |
b2821ae6 SR |
63 | /* |
64 | * If a tracer is running, we do not want to run SELFTEST. | |
65 | */ | |
020e5f85 | 66 | bool __read_mostly tracing_selftest_disabled; |
b2821ae6 | 67 | |
0daa2302 SRRH |
68 | /* Pipe tracepoints to printk */ |
69 | struct trace_iterator *tracepoint_print_iter; | |
70 | int tracepoint_printk; | |
71 | ||
adf9f195 FW |
72 | /* For tracers that don't implement custom flags */ |
73 | static struct tracer_opt dummy_tracer_opt[] = { | |
74 | { } | |
75 | }; | |
76 | ||
8c1a49ae SRRH |
77 | static int |
78 | dummy_set_flag(struct trace_array *tr, u32 old_flags, u32 bit, int set) | |
adf9f195 FW |
79 | { |
80 | return 0; | |
81 | } | |
0f048701 | 82 | |
7ffbd48d SR |
83 | /* |
84 | * To prevent the comm cache from being overwritten when no | |
85 | * tracing is active, only save the comm when a trace event | |
86 | * occurred. | |
87 | */ | |
88 | static DEFINE_PER_CPU(bool, trace_cmdline_save); | |
89 | ||
0f048701 SR |
90 | /* |
91 | * Kill all tracing for good (never come back). | |
92 | * It is initialized to 1 but will turn to zero if the initialization | |
93 | * of the tracer is successful. But that is the only place that sets | |
94 | * this back to zero. | |
95 | */ | |
4fd27358 | 96 | static int tracing_disabled = 1; |
0f048701 | 97 | |
955b61e5 | 98 | cpumask_var_t __read_mostly tracing_buffer_mask; |
ab46428c | 99 | |
944ac425 SR |
100 | /* |
101 | * ftrace_dump_on_oops - variable to dump ftrace buffer on oops | |
102 | * | |
103 | * If there is an oops (or kernel panic) and the ftrace_dump_on_oops | |
104 | * is set, then ftrace_dump is called. This will output the contents | |
105 | * of the ftrace buffers to the console. This is very useful for | |
106 | * capturing traces that lead to crashes and outputing it to a | |
107 | * serial console. | |
108 | * | |
109 | * It is default off, but you can enable it with either specifying | |
110 | * "ftrace_dump_on_oops" in the kernel command line, or setting | |
cecbca96 FW |
111 | * /proc/sys/kernel/ftrace_dump_on_oops |
112 | * Set 1 if you want to dump buffers of all CPUs | |
113 | * Set 2 if you want to dump the buffer of the CPU that triggered oops | |
944ac425 | 114 | */ |
cecbca96 FW |
115 | |
116 | enum ftrace_dump_mode ftrace_dump_on_oops; | |
944ac425 | 117 | |
de7edd31 SRRH |
118 | /* When set, tracing will stop when a WARN*() is hit */ |
119 | int __disable_trace_on_warning; | |
120 | ||
9828413d SRRH |
121 | #ifdef CONFIG_TRACE_ENUM_MAP_FILE |
122 | /* Map of enums to their values, for "enum_map" file */ | |
123 | struct trace_enum_map_head { | |
124 | struct module *mod; | |
125 | unsigned long length; | |
126 | }; | |
127 | ||
128 | union trace_enum_map_item; | |
129 | ||
130 | struct trace_enum_map_tail { | |
131 | /* | |
132 | * "end" is first and points to NULL as it must be different | |
133 | * than "mod" or "enum_string" | |
134 | */ | |
135 | union trace_enum_map_item *next; | |
136 | const char *end; /* points to NULL */ | |
137 | }; | |
138 | ||
139 | static DEFINE_MUTEX(trace_enum_mutex); | |
140 | ||
141 | /* | |
142 | * The trace_enum_maps are saved in an array with two extra elements, | |
143 | * one at the beginning, and one at the end. The beginning item contains | |
144 | * the count of the saved maps (head.length), and the module they | |
145 | * belong to if not built in (head.mod). The ending item contains a | |
146 | * pointer to the next array of saved enum_map items. | |
147 | */ | |
148 | union trace_enum_map_item { | |
149 | struct trace_enum_map map; | |
150 | struct trace_enum_map_head head; | |
151 | struct trace_enum_map_tail tail; | |
152 | }; | |
153 | ||
154 | static union trace_enum_map_item *trace_enum_maps; | |
155 | #endif /* CONFIG_TRACE_ENUM_MAP_FILE */ | |
156 | ||
607e2ea1 | 157 | static int tracing_set_tracer(struct trace_array *tr, const char *buf); |
b2821ae6 | 158 | |
ee6c2c1b LZ |
159 | #define MAX_TRACER_SIZE 100 |
160 | static char bootup_tracer_buf[MAX_TRACER_SIZE] __initdata; | |
b2821ae6 | 161 | static char *default_bootup_tracer; |
d9e54076 | 162 | |
55034cd6 SRRH |
163 | static bool allocate_snapshot; |
164 | ||
1beee96b | 165 | static int __init set_cmdline_ftrace(char *str) |
d9e54076 | 166 | { |
67012ab1 | 167 | strlcpy(bootup_tracer_buf, str, MAX_TRACER_SIZE); |
b2821ae6 | 168 | default_bootup_tracer = bootup_tracer_buf; |
73c5162a | 169 | /* We are using ftrace early, expand it */ |
55034cd6 | 170 | ring_buffer_expanded = true; |
d9e54076 PZ |
171 | return 1; |
172 | } | |
1beee96b | 173 | __setup("ftrace=", set_cmdline_ftrace); |
d9e54076 | 174 | |
944ac425 SR |
175 | static int __init set_ftrace_dump_on_oops(char *str) |
176 | { | |
cecbca96 FW |
177 | if (*str++ != '=' || !*str) { |
178 | ftrace_dump_on_oops = DUMP_ALL; | |
179 | return 1; | |
180 | } | |
181 | ||
182 | if (!strcmp("orig_cpu", str)) { | |
183 | ftrace_dump_on_oops = DUMP_ORIG; | |
184 | return 1; | |
185 | } | |
186 | ||
187 | return 0; | |
944ac425 SR |
188 | } |
189 | __setup("ftrace_dump_on_oops", set_ftrace_dump_on_oops); | |
60a11774 | 190 | |
de7edd31 SRRH |
191 | static int __init stop_trace_on_warning(char *str) |
192 | { | |
933ff9f2 LCG |
193 | if ((strcmp(str, "=0") != 0 && strcmp(str, "=off") != 0)) |
194 | __disable_trace_on_warning = 1; | |
de7edd31 SRRH |
195 | return 1; |
196 | } | |
933ff9f2 | 197 | __setup("traceoff_on_warning", stop_trace_on_warning); |
de7edd31 | 198 | |
3209cff4 | 199 | static int __init boot_alloc_snapshot(char *str) |
55034cd6 SRRH |
200 | { |
201 | allocate_snapshot = true; | |
202 | /* We also need the main ring buffer expanded */ | |
203 | ring_buffer_expanded = true; | |
204 | return 1; | |
205 | } | |
3209cff4 | 206 | __setup("alloc_snapshot", boot_alloc_snapshot); |
55034cd6 | 207 | |
7bcfaf54 SR |
208 | |
209 | static char trace_boot_options_buf[MAX_TRACER_SIZE] __initdata; | |
7bcfaf54 SR |
210 | |
211 | static int __init set_trace_boot_options(char *str) | |
212 | { | |
67012ab1 | 213 | strlcpy(trace_boot_options_buf, str, MAX_TRACER_SIZE); |
7bcfaf54 SR |
214 | return 0; |
215 | } | |
216 | __setup("trace_options=", set_trace_boot_options); | |
217 | ||
e1e232ca SR |
218 | static char trace_boot_clock_buf[MAX_TRACER_SIZE] __initdata; |
219 | static char *trace_boot_clock __initdata; | |
220 | ||
221 | static int __init set_trace_boot_clock(char *str) | |
222 | { | |
223 | strlcpy(trace_boot_clock_buf, str, MAX_TRACER_SIZE); | |
224 | trace_boot_clock = trace_boot_clock_buf; | |
225 | return 0; | |
226 | } | |
227 | __setup("trace_clock=", set_trace_boot_clock); | |
228 | ||
0daa2302 SRRH |
229 | static int __init set_tracepoint_printk(char *str) |
230 | { | |
231 | if ((strcmp(str, "=0") != 0 && strcmp(str, "=off") != 0)) | |
232 | tracepoint_printk = 1; | |
233 | return 1; | |
234 | } | |
235 | __setup("tp_printk", set_tracepoint_printk); | |
de7edd31 | 236 | |
cf8e3474 | 237 | unsigned long long ns2usecs(cycle_t nsec) |
bc0c38d1 SR |
238 | { |
239 | nsec += 500; | |
240 | do_div(nsec, 1000); | |
241 | return nsec; | |
242 | } | |
243 | ||
983f938a SRRH |
244 | /* trace_flags holds trace_options default values */ |
245 | #define TRACE_DEFAULT_FLAGS \ | |
246 | (FUNCTION_DEFAULT_FLAGS | \ | |
247 | TRACE_ITER_PRINT_PARENT | TRACE_ITER_PRINTK | \ | |
248 | TRACE_ITER_ANNOTATE | TRACE_ITER_CONTEXT_INFO | \ | |
249 | TRACE_ITER_RECORD_CMD | TRACE_ITER_OVERWRITE | \ | |
250 | TRACE_ITER_IRQ_INFO | TRACE_ITER_MARKERS) | |
251 | ||
16270145 SRRH |
252 | /* trace_options that are only supported by global_trace */ |
253 | #define TOP_LEVEL_TRACE_FLAGS (TRACE_ITER_PRINTK | \ | |
254 | TRACE_ITER_PRINTK_MSGONLY | TRACE_ITER_RECORD_CMD) | |
255 | ||
20550622 SRRH |
256 | /* trace_flags that are default zero for instances */ |
257 | #define ZEROED_TRACE_FLAGS \ | |
258 | TRACE_ITER_EVENT_FORK | |
16270145 | 259 | |
4fcdae83 SR |
260 | /* |
261 | * The global_trace is the descriptor that holds the tracing | |
262 | * buffers for the live tracing. For each CPU, it contains | |
263 | * a link list of pages that will store trace entries. The | |
264 | * page descriptor of the pages in the memory is used to hold | |
265 | * the link list by linking the lru item in the page descriptor | |
266 | * to each of the pages in the buffer per CPU. | |
267 | * | |
268 | * For each active CPU there is a data field that holds the | |
269 | * pages for the buffer for that CPU. Each CPU has the same number | |
270 | * of pages allocated for its buffer. | |
271 | */ | |
983f938a SRRH |
272 | static struct trace_array global_trace = { |
273 | .trace_flags = TRACE_DEFAULT_FLAGS, | |
274 | }; | |
bc0c38d1 | 275 | |
ae63b31e | 276 | LIST_HEAD(ftrace_trace_arrays); |
bc0c38d1 | 277 | |
ff451961 SRRH |
278 | int trace_array_get(struct trace_array *this_tr) |
279 | { | |
280 | struct trace_array *tr; | |
281 | int ret = -ENODEV; | |
282 | ||
283 | mutex_lock(&trace_types_lock); | |
284 | list_for_each_entry(tr, &ftrace_trace_arrays, list) { | |
285 | if (tr == this_tr) { | |
286 | tr->ref++; | |
287 | ret = 0; | |
288 | break; | |
289 | } | |
290 | } | |
291 | mutex_unlock(&trace_types_lock); | |
292 | ||
293 | return ret; | |
294 | } | |
295 | ||
296 | static void __trace_array_put(struct trace_array *this_tr) | |
297 | { | |
298 | WARN_ON(!this_tr->ref); | |
299 | this_tr->ref--; | |
300 | } | |
301 | ||
302 | void trace_array_put(struct trace_array *this_tr) | |
303 | { | |
304 | mutex_lock(&trace_types_lock); | |
305 | __trace_array_put(this_tr); | |
306 | mutex_unlock(&trace_types_lock); | |
307 | } | |
308 | ||
2425bcb9 | 309 | int call_filter_check_discard(struct trace_event_call *call, void *rec, |
f306cc82 TZ |
310 | struct ring_buffer *buffer, |
311 | struct ring_buffer_event *event) | |
312 | { | |
313 | if (unlikely(call->flags & TRACE_EVENT_FL_FILTERED) && | |
314 | !filter_match_preds(call->filter, rec)) { | |
0fc1b09f | 315 | __trace_event_discard_commit(buffer, event); |
f306cc82 TZ |
316 | return 1; |
317 | } | |
318 | ||
319 | return 0; | |
eb02ce01 TZ |
320 | } |
321 | ||
76c813e2 SRRH |
322 | void trace_free_pid_list(struct trace_pid_list *pid_list) |
323 | { | |
324 | vfree(pid_list->pids); | |
325 | kfree(pid_list); | |
326 | } | |
327 | ||
d8275c45 SR |
328 | /** |
329 | * trace_find_filtered_pid - check if a pid exists in a filtered_pid list | |
330 | * @filtered_pids: The list of pids to check | |
331 | * @search_pid: The PID to find in @filtered_pids | |
332 | * | |
333 | * Returns true if @search_pid is fonud in @filtered_pids, and false otherwis. | |
334 | */ | |
335 | bool | |
336 | trace_find_filtered_pid(struct trace_pid_list *filtered_pids, pid_t search_pid) | |
337 | { | |
338 | /* | |
339 | * If pid_max changed after filtered_pids was created, we | |
340 | * by default ignore all pids greater than the previous pid_max. | |
341 | */ | |
342 | if (search_pid >= filtered_pids->pid_max) | |
343 | return false; | |
344 | ||
345 | return test_bit(search_pid, filtered_pids->pids); | |
346 | } | |
347 | ||
348 | /** | |
349 | * trace_ignore_this_task - should a task be ignored for tracing | |
350 | * @filtered_pids: The list of pids to check | |
351 | * @task: The task that should be ignored if not filtered | |
352 | * | |
353 | * Checks if @task should be traced or not from @filtered_pids. | |
354 | * Returns true if @task should *NOT* be traced. | |
355 | * Returns false if @task should be traced. | |
356 | */ | |
357 | bool | |
358 | trace_ignore_this_task(struct trace_pid_list *filtered_pids, struct task_struct *task) | |
359 | { | |
360 | /* | |
361 | * Return false, because if filtered_pids does not exist, | |
362 | * all pids are good to trace. | |
363 | */ | |
364 | if (!filtered_pids) | |
365 | return false; | |
366 | ||
367 | return !trace_find_filtered_pid(filtered_pids, task->pid); | |
368 | } | |
369 | ||
370 | /** | |
371 | * trace_pid_filter_add_remove - Add or remove a task from a pid_list | |
372 | * @pid_list: The list to modify | |
373 | * @self: The current task for fork or NULL for exit | |
374 | * @task: The task to add or remove | |
375 | * | |
376 | * If adding a task, if @self is defined, the task is only added if @self | |
377 | * is also included in @pid_list. This happens on fork and tasks should | |
378 | * only be added when the parent is listed. If @self is NULL, then the | |
379 | * @task pid will be removed from the list, which would happen on exit | |
380 | * of a task. | |
381 | */ | |
382 | void trace_filter_add_remove_task(struct trace_pid_list *pid_list, | |
383 | struct task_struct *self, | |
384 | struct task_struct *task) | |
385 | { | |
386 | if (!pid_list) | |
387 | return; | |
388 | ||
389 | /* For forks, we only add if the forking task is listed */ | |
390 | if (self) { | |
391 | if (!trace_find_filtered_pid(pid_list, self->pid)) | |
392 | return; | |
393 | } | |
394 | ||
395 | /* Sorry, but we don't support pid_max changing after setting */ | |
396 | if (task->pid >= pid_list->pid_max) | |
397 | return; | |
398 | ||
399 | /* "self" is set for forks, and NULL for exits */ | |
400 | if (self) | |
401 | set_bit(task->pid, pid_list->pids); | |
402 | else | |
403 | clear_bit(task->pid, pid_list->pids); | |
404 | } | |
405 | ||
5cc8976b SRRH |
406 | /** |
407 | * trace_pid_next - Used for seq_file to get to the next pid of a pid_list | |
408 | * @pid_list: The pid list to show | |
409 | * @v: The last pid that was shown (+1 the actual pid to let zero be displayed) | |
410 | * @pos: The position of the file | |
411 | * | |
412 | * This is used by the seq_file "next" operation to iterate the pids | |
413 | * listed in a trace_pid_list structure. | |
414 | * | |
415 | * Returns the pid+1 as we want to display pid of zero, but NULL would | |
416 | * stop the iteration. | |
417 | */ | |
418 | void *trace_pid_next(struct trace_pid_list *pid_list, void *v, loff_t *pos) | |
419 | { | |
420 | unsigned long pid = (unsigned long)v; | |
421 | ||
422 | (*pos)++; | |
423 | ||
424 | /* pid already is +1 of the actual prevous bit */ | |
425 | pid = find_next_bit(pid_list->pids, pid_list->pid_max, pid); | |
426 | ||
427 | /* Return pid + 1 to allow zero to be represented */ | |
428 | if (pid < pid_list->pid_max) | |
429 | return (void *)(pid + 1); | |
430 | ||
431 | return NULL; | |
432 | } | |
433 | ||
434 | /** | |
435 | * trace_pid_start - Used for seq_file to start reading pid lists | |
436 | * @pid_list: The pid list to show | |
437 | * @pos: The position of the file | |
438 | * | |
439 | * This is used by seq_file "start" operation to start the iteration | |
440 | * of listing pids. | |
441 | * | |
442 | * Returns the pid+1 as we want to display pid of zero, but NULL would | |
443 | * stop the iteration. | |
444 | */ | |
445 | void *trace_pid_start(struct trace_pid_list *pid_list, loff_t *pos) | |
446 | { | |
447 | unsigned long pid; | |
448 | loff_t l = 0; | |
449 | ||
450 | pid = find_first_bit(pid_list->pids, pid_list->pid_max); | |
451 | if (pid >= pid_list->pid_max) | |
452 | return NULL; | |
453 | ||
454 | /* Return pid + 1 so that zero can be the exit value */ | |
455 | for (pid++; pid && l < *pos; | |
456 | pid = (unsigned long)trace_pid_next(pid_list, (void *)pid, &l)) | |
457 | ; | |
458 | return (void *)pid; | |
459 | } | |
460 | ||
461 | /** | |
462 | * trace_pid_show - show the current pid in seq_file processing | |
463 | * @m: The seq_file structure to write into | |
464 | * @v: A void pointer of the pid (+1) value to display | |
465 | * | |
466 | * Can be directly used by seq_file operations to display the current | |
467 | * pid value. | |
468 | */ | |
469 | int trace_pid_show(struct seq_file *m, void *v) | |
470 | { | |
471 | unsigned long pid = (unsigned long)v - 1; | |
472 | ||
473 | seq_printf(m, "%lu\n", pid); | |
474 | return 0; | |
475 | } | |
476 | ||
76c813e2 SRRH |
477 | /* 128 should be much more than enough */ |
478 | #define PID_BUF_SIZE 127 | |
479 | ||
480 | int trace_pid_write(struct trace_pid_list *filtered_pids, | |
481 | struct trace_pid_list **new_pid_list, | |
482 | const char __user *ubuf, size_t cnt) | |
483 | { | |
484 | struct trace_pid_list *pid_list; | |
485 | struct trace_parser parser; | |
486 | unsigned long val; | |
487 | int nr_pids = 0; | |
488 | ssize_t read = 0; | |
489 | ssize_t ret = 0; | |
490 | loff_t pos; | |
491 | pid_t pid; | |
492 | ||
493 | if (trace_parser_get_init(&parser, PID_BUF_SIZE + 1)) | |
494 | return -ENOMEM; | |
495 | ||
496 | /* | |
497 | * Always recreate a new array. The write is an all or nothing | |
498 | * operation. Always create a new array when adding new pids by | |
499 | * the user. If the operation fails, then the current list is | |
500 | * not modified. | |
501 | */ | |
502 | pid_list = kmalloc(sizeof(*pid_list), GFP_KERNEL); | |
503 | if (!pid_list) | |
504 | return -ENOMEM; | |
505 | ||
506 | pid_list->pid_max = READ_ONCE(pid_max); | |
507 | ||
508 | /* Only truncating will shrink pid_max */ | |
509 | if (filtered_pids && filtered_pids->pid_max > pid_list->pid_max) | |
510 | pid_list->pid_max = filtered_pids->pid_max; | |
511 | ||
512 | pid_list->pids = vzalloc((pid_list->pid_max + 7) >> 3); | |
513 | if (!pid_list->pids) { | |
514 | kfree(pid_list); | |
515 | return -ENOMEM; | |
516 | } | |
517 | ||
518 | if (filtered_pids) { | |
519 | /* copy the current bits to the new max */ | |
67f20b08 WY |
520 | for_each_set_bit(pid, filtered_pids->pids, |
521 | filtered_pids->pid_max) { | |
76c813e2 | 522 | set_bit(pid, pid_list->pids); |
76c813e2 SRRH |
523 | nr_pids++; |
524 | } | |
525 | } | |
526 | ||
527 | while (cnt > 0) { | |
528 | ||
529 | pos = 0; | |
530 | ||
531 | ret = trace_get_user(&parser, ubuf, cnt, &pos); | |
532 | if (ret < 0 || !trace_parser_loaded(&parser)) | |
533 | break; | |
534 | ||
535 | read += ret; | |
536 | ubuf += ret; | |
537 | cnt -= ret; | |
538 | ||
539 | parser.buffer[parser.idx] = 0; | |
540 | ||
541 | ret = -EINVAL; | |
542 | if (kstrtoul(parser.buffer, 0, &val)) | |
543 | break; | |
544 | if (val >= pid_list->pid_max) | |
545 | break; | |
546 | ||
547 | pid = (pid_t)val; | |
548 | ||
549 | set_bit(pid, pid_list->pids); | |
550 | nr_pids++; | |
551 | ||
552 | trace_parser_clear(&parser); | |
553 | ret = 0; | |
554 | } | |
555 | trace_parser_put(&parser); | |
556 | ||
557 | if (ret < 0) { | |
558 | trace_free_pid_list(pid_list); | |
559 | return ret; | |
560 | } | |
561 | ||
562 | if (!nr_pids) { | |
563 | /* Cleared the list of pids */ | |
564 | trace_free_pid_list(pid_list); | |
565 | read = ret; | |
566 | pid_list = NULL; | |
567 | } | |
568 | ||
569 | *new_pid_list = pid_list; | |
570 | ||
571 | return read; | |
572 | } | |
573 | ||
ad1438a0 | 574 | static cycle_t buffer_ftrace_now(struct trace_buffer *buf, int cpu) |
37886f6a SR |
575 | { |
576 | u64 ts; | |
577 | ||
578 | /* Early boot up does not have a buffer yet */ | |
9457158b | 579 | if (!buf->buffer) |
37886f6a SR |
580 | return trace_clock_local(); |
581 | ||
9457158b AL |
582 | ts = ring_buffer_time_stamp(buf->buffer, cpu); |
583 | ring_buffer_normalize_time_stamp(buf->buffer, cpu, &ts); | |
37886f6a SR |
584 | |
585 | return ts; | |
586 | } | |
bc0c38d1 | 587 | |
9457158b AL |
588 | cycle_t ftrace_now(int cpu) |
589 | { | |
590 | return buffer_ftrace_now(&global_trace.trace_buffer, cpu); | |
591 | } | |
592 | ||
10246fa3 SRRH |
593 | /** |
594 | * tracing_is_enabled - Show if global_trace has been disabled | |
595 | * | |
596 | * Shows if the global trace has been enabled or not. It uses the | |
597 | * mirror flag "buffer_disabled" to be used in fast paths such as for | |
598 | * the irqsoff tracer. But it may be inaccurate due to races. If you | |
599 | * need to know the accurate state, use tracing_is_on() which is a little | |
600 | * slower, but accurate. | |
601 | */ | |
9036990d SR |
602 | int tracing_is_enabled(void) |
603 | { | |
10246fa3 SRRH |
604 | /* |
605 | * For quick access (irqsoff uses this in fast path), just | |
606 | * return the mirror variable of the state of the ring buffer. | |
607 | * It's a little racy, but we don't really care. | |
608 | */ | |
609 | smp_rmb(); | |
610 | return !global_trace.buffer_disabled; | |
9036990d SR |
611 | } |
612 | ||
4fcdae83 | 613 | /* |
3928a8a2 SR |
614 | * trace_buf_size is the size in bytes that is allocated |
615 | * for a buffer. Note, the number of bytes is always rounded | |
616 | * to page size. | |
3f5a54e3 SR |
617 | * |
618 | * This number is purposely set to a low number of 16384. | |
619 | * If the dump on oops happens, it will be much appreciated | |
620 | * to not have to wait for all that output. Anyway this can be | |
621 | * boot time and run time configurable. | |
4fcdae83 | 622 | */ |
3928a8a2 | 623 | #define TRACE_BUF_SIZE_DEFAULT 1441792UL /* 16384 * 88 (sizeof(entry)) */ |
3f5a54e3 | 624 | |
3928a8a2 | 625 | static unsigned long trace_buf_size = TRACE_BUF_SIZE_DEFAULT; |
bc0c38d1 | 626 | |
4fcdae83 | 627 | /* trace_types holds a link list of available tracers. */ |
bc0c38d1 | 628 | static struct tracer *trace_types __read_mostly; |
4fcdae83 | 629 | |
4fcdae83 SR |
630 | /* |
631 | * trace_types_lock is used to protect the trace_types list. | |
4fcdae83 | 632 | */ |
a8227415 | 633 | DEFINE_MUTEX(trace_types_lock); |
4fcdae83 | 634 | |
7e53bd42 LJ |
635 | /* |
636 | * serialize the access of the ring buffer | |
637 | * | |
638 | * ring buffer serializes readers, but it is low level protection. | |
639 | * The validity of the events (which returns by ring_buffer_peek() ..etc) | |
640 | * are not protected by ring buffer. | |
641 | * | |
642 | * The content of events may become garbage if we allow other process consumes | |
643 | * these events concurrently: | |
644 | * A) the page of the consumed events may become a normal page | |
645 | * (not reader page) in ring buffer, and this page will be rewrited | |
646 | * by events producer. | |
647 | * B) The page of the consumed events may become a page for splice_read, | |
648 | * and this page will be returned to system. | |
649 | * | |
650 | * These primitives allow multi process access to different cpu ring buffer | |
651 | * concurrently. | |
652 | * | |
653 | * These primitives don't distinguish read-only and read-consume access. | |
654 | * Multi read-only access are also serialized. | |
655 | */ | |
656 | ||
657 | #ifdef CONFIG_SMP | |
658 | static DECLARE_RWSEM(all_cpu_access_lock); | |
659 | static DEFINE_PER_CPU(struct mutex, cpu_access_lock); | |
660 | ||
661 | static inline void trace_access_lock(int cpu) | |
662 | { | |
ae3b5093 | 663 | if (cpu == RING_BUFFER_ALL_CPUS) { |
7e53bd42 LJ |
664 | /* gain it for accessing the whole ring buffer. */ |
665 | down_write(&all_cpu_access_lock); | |
666 | } else { | |
667 | /* gain it for accessing a cpu ring buffer. */ | |
668 | ||
ae3b5093 | 669 | /* Firstly block other trace_access_lock(RING_BUFFER_ALL_CPUS). */ |
7e53bd42 LJ |
670 | down_read(&all_cpu_access_lock); |
671 | ||
672 | /* Secondly block other access to this @cpu ring buffer. */ | |
673 | mutex_lock(&per_cpu(cpu_access_lock, cpu)); | |
674 | } | |
675 | } | |
676 | ||
677 | static inline void trace_access_unlock(int cpu) | |
678 | { | |
ae3b5093 | 679 | if (cpu == RING_BUFFER_ALL_CPUS) { |
7e53bd42 LJ |
680 | up_write(&all_cpu_access_lock); |
681 | } else { | |
682 | mutex_unlock(&per_cpu(cpu_access_lock, cpu)); | |
683 | up_read(&all_cpu_access_lock); | |
684 | } | |
685 | } | |
686 | ||
687 | static inline void trace_access_lock_init(void) | |
688 | { | |
689 | int cpu; | |
690 | ||
691 | for_each_possible_cpu(cpu) | |
692 | mutex_init(&per_cpu(cpu_access_lock, cpu)); | |
693 | } | |
694 | ||
695 | #else | |
696 | ||
697 | static DEFINE_MUTEX(access_lock); | |
698 | ||
699 | static inline void trace_access_lock(int cpu) | |
700 | { | |
701 | (void)cpu; | |
702 | mutex_lock(&access_lock); | |
703 | } | |
704 | ||
705 | static inline void trace_access_unlock(int cpu) | |
706 | { | |
707 | (void)cpu; | |
708 | mutex_unlock(&access_lock); | |
709 | } | |
710 | ||
711 | static inline void trace_access_lock_init(void) | |
712 | { | |
713 | } | |
714 | ||
715 | #endif | |
716 | ||
d78a4614 SRRH |
717 | #ifdef CONFIG_STACKTRACE |
718 | static void __ftrace_trace_stack(struct ring_buffer *buffer, | |
719 | unsigned long flags, | |
720 | int skip, int pc, struct pt_regs *regs); | |
2d34f489 SRRH |
721 | static inline void ftrace_trace_stack(struct trace_array *tr, |
722 | struct ring_buffer *buffer, | |
73dddbb5 SRRH |
723 | unsigned long flags, |
724 | int skip, int pc, struct pt_regs *regs); | |
ca475e83 | 725 | |
d78a4614 SRRH |
726 | #else |
727 | static inline void __ftrace_trace_stack(struct ring_buffer *buffer, | |
728 | unsigned long flags, | |
729 | int skip, int pc, struct pt_regs *regs) | |
730 | { | |
731 | } | |
2d34f489 SRRH |
732 | static inline void ftrace_trace_stack(struct trace_array *tr, |
733 | struct ring_buffer *buffer, | |
73dddbb5 SRRH |
734 | unsigned long flags, |
735 | int skip, int pc, struct pt_regs *regs) | |
ca475e83 SRRH |
736 | { |
737 | } | |
738 | ||
d78a4614 SRRH |
739 | #endif |
740 | ||
5280bcef | 741 | static void tracer_tracing_on(struct trace_array *tr) |
10246fa3 SRRH |
742 | { |
743 | if (tr->trace_buffer.buffer) | |
744 | ring_buffer_record_on(tr->trace_buffer.buffer); | |
745 | /* | |
746 | * This flag is looked at when buffers haven't been allocated | |
747 | * yet, or by some tracers (like irqsoff), that just want to | |
748 | * know if the ring buffer has been disabled, but it can handle | |
749 | * races of where it gets disabled but we still do a record. | |
750 | * As the check is in the fast path of the tracers, it is more | |
751 | * important to be fast than accurate. | |
752 | */ | |
753 | tr->buffer_disabled = 0; | |
754 | /* Make the flag seen by readers */ | |
755 | smp_wmb(); | |
756 | } | |
757 | ||
499e5470 SR |
758 | /** |
759 | * tracing_on - enable tracing buffers | |
760 | * | |
761 | * This function enables tracing buffers that may have been | |
762 | * disabled with tracing_off. | |
763 | */ | |
764 | void tracing_on(void) | |
765 | { | |
10246fa3 | 766 | tracer_tracing_on(&global_trace); |
499e5470 SR |
767 | } |
768 | EXPORT_SYMBOL_GPL(tracing_on); | |
769 | ||
09ae7234 SRRH |
770 | /** |
771 | * __trace_puts - write a constant string into the trace buffer. | |
772 | * @ip: The address of the caller | |
773 | * @str: The constant string to write | |
774 | * @size: The size of the string. | |
775 | */ | |
776 | int __trace_puts(unsigned long ip, const char *str, int size) | |
777 | { | |
778 | struct ring_buffer_event *event; | |
779 | struct ring_buffer *buffer; | |
780 | struct print_entry *entry; | |
781 | unsigned long irq_flags; | |
782 | int alloc; | |
8abfb872 J |
783 | int pc; |
784 | ||
983f938a | 785 | if (!(global_trace.trace_flags & TRACE_ITER_PRINTK)) |
f0160a5a J |
786 | return 0; |
787 | ||
8abfb872 | 788 | pc = preempt_count(); |
09ae7234 | 789 | |
3132e107 SRRH |
790 | if (unlikely(tracing_selftest_running || tracing_disabled)) |
791 | return 0; | |
792 | ||
09ae7234 SRRH |
793 | alloc = sizeof(*entry) + size + 2; /* possible \n added */ |
794 | ||
795 | local_save_flags(irq_flags); | |
796 | buffer = global_trace.trace_buffer.buffer; | |
797 | event = trace_buffer_lock_reserve(buffer, TRACE_PRINT, alloc, | |
8abfb872 | 798 | irq_flags, pc); |
09ae7234 SRRH |
799 | if (!event) |
800 | return 0; | |
801 | ||
802 | entry = ring_buffer_event_data(event); | |
803 | entry->ip = ip; | |
804 | ||
805 | memcpy(&entry->buf, str, size); | |
806 | ||
807 | /* Add a newline if necessary */ | |
808 | if (entry->buf[size - 1] != '\n') { | |
809 | entry->buf[size] = '\n'; | |
810 | entry->buf[size + 1] = '\0'; | |
811 | } else | |
812 | entry->buf[size] = '\0'; | |
813 | ||
814 | __buffer_unlock_commit(buffer, event); | |
2d34f489 | 815 | ftrace_trace_stack(&global_trace, buffer, irq_flags, 4, pc, NULL); |
09ae7234 SRRH |
816 | |
817 | return size; | |
818 | } | |
819 | EXPORT_SYMBOL_GPL(__trace_puts); | |
820 | ||
821 | /** | |
822 | * __trace_bputs - write the pointer to a constant string into trace buffer | |
823 | * @ip: The address of the caller | |
824 | * @str: The constant string to write to the buffer to | |
825 | */ | |
826 | int __trace_bputs(unsigned long ip, const char *str) | |
827 | { | |
828 | struct ring_buffer_event *event; | |
829 | struct ring_buffer *buffer; | |
830 | struct bputs_entry *entry; | |
831 | unsigned long irq_flags; | |
832 | int size = sizeof(struct bputs_entry); | |
8abfb872 J |
833 | int pc; |
834 | ||
983f938a | 835 | if (!(global_trace.trace_flags & TRACE_ITER_PRINTK)) |
f0160a5a J |
836 | return 0; |
837 | ||
8abfb872 | 838 | pc = preempt_count(); |
09ae7234 | 839 | |
3132e107 SRRH |
840 | if (unlikely(tracing_selftest_running || tracing_disabled)) |
841 | return 0; | |
842 | ||
09ae7234 SRRH |
843 | local_save_flags(irq_flags); |
844 | buffer = global_trace.trace_buffer.buffer; | |
845 | event = trace_buffer_lock_reserve(buffer, TRACE_BPUTS, size, | |
8abfb872 | 846 | irq_flags, pc); |
09ae7234 SRRH |
847 | if (!event) |
848 | return 0; | |
849 | ||
850 | entry = ring_buffer_event_data(event); | |
851 | entry->ip = ip; | |
852 | entry->str = str; | |
853 | ||
854 | __buffer_unlock_commit(buffer, event); | |
2d34f489 | 855 | ftrace_trace_stack(&global_trace, buffer, irq_flags, 4, pc, NULL); |
09ae7234 SRRH |
856 | |
857 | return 1; | |
858 | } | |
859 | EXPORT_SYMBOL_GPL(__trace_bputs); | |
860 | ||
ad909e21 SRRH |
861 | #ifdef CONFIG_TRACER_SNAPSHOT |
862 | /** | |
863 | * trace_snapshot - take a snapshot of the current buffer. | |
864 | * | |
865 | * This causes a swap between the snapshot buffer and the current live | |
866 | * tracing buffer. You can use this to take snapshots of the live | |
867 | * trace when some condition is triggered, but continue to trace. | |
868 | * | |
869 | * Note, make sure to allocate the snapshot with either | |
870 | * a tracing_snapshot_alloc(), or by doing it manually | |
871 | * with: echo 1 > /sys/kernel/debug/tracing/snapshot | |
872 | * | |
873 | * If the snapshot buffer is not allocated, it will stop tracing. | |
874 | * Basically making a permanent snapshot. | |
875 | */ | |
876 | void tracing_snapshot(void) | |
877 | { | |
878 | struct trace_array *tr = &global_trace; | |
879 | struct tracer *tracer = tr->current_trace; | |
880 | unsigned long flags; | |
881 | ||
1b22e382 SRRH |
882 | if (in_nmi()) { |
883 | internal_trace_puts("*** SNAPSHOT CALLED FROM NMI CONTEXT ***\n"); | |
884 | internal_trace_puts("*** snapshot is being ignored ***\n"); | |
885 | return; | |
886 | } | |
887 | ||
ad909e21 | 888 | if (!tr->allocated_snapshot) { |
ca268da6 SRRH |
889 | internal_trace_puts("*** SNAPSHOT NOT ALLOCATED ***\n"); |
890 | internal_trace_puts("*** stopping trace here! ***\n"); | |
ad909e21 SRRH |
891 | tracing_off(); |
892 | return; | |
893 | } | |
894 | ||
895 | /* Note, snapshot can not be used when the tracer uses it */ | |
896 | if (tracer->use_max_tr) { | |
ca268da6 SRRH |
897 | internal_trace_puts("*** LATENCY TRACER ACTIVE ***\n"); |
898 | internal_trace_puts("*** Can not use snapshot (sorry) ***\n"); | |
ad909e21 SRRH |
899 | return; |
900 | } | |
901 | ||
902 | local_irq_save(flags); | |
903 | update_max_tr(tr, current, smp_processor_id()); | |
904 | local_irq_restore(flags); | |
905 | } | |
1b22e382 | 906 | EXPORT_SYMBOL_GPL(tracing_snapshot); |
ad909e21 SRRH |
907 | |
908 | static int resize_buffer_duplicate_size(struct trace_buffer *trace_buf, | |
909 | struct trace_buffer *size_buf, int cpu_id); | |
3209cff4 SRRH |
910 | static void set_buffer_entries(struct trace_buffer *buf, unsigned long val); |
911 | ||
912 | static int alloc_snapshot(struct trace_array *tr) | |
913 | { | |
914 | int ret; | |
915 | ||
916 | if (!tr->allocated_snapshot) { | |
917 | ||
918 | /* allocate spare buffer */ | |
919 | ret = resize_buffer_duplicate_size(&tr->max_buffer, | |
920 | &tr->trace_buffer, RING_BUFFER_ALL_CPUS); | |
921 | if (ret < 0) | |
922 | return ret; | |
923 | ||
924 | tr->allocated_snapshot = true; | |
925 | } | |
926 | ||
927 | return 0; | |
928 | } | |
929 | ||
ad1438a0 | 930 | static void free_snapshot(struct trace_array *tr) |
3209cff4 SRRH |
931 | { |
932 | /* | |
933 | * We don't free the ring buffer. instead, resize it because | |
934 | * The max_tr ring buffer has some state (e.g. ring->clock) and | |
935 | * we want preserve it. | |
936 | */ | |
937 | ring_buffer_resize(tr->max_buffer.buffer, 1, RING_BUFFER_ALL_CPUS); | |
938 | set_buffer_entries(&tr->max_buffer, 1); | |
939 | tracing_reset_online_cpus(&tr->max_buffer); | |
940 | tr->allocated_snapshot = false; | |
941 | } | |
ad909e21 | 942 | |
93e31ffb TZ |
943 | /** |
944 | * tracing_alloc_snapshot - allocate snapshot buffer. | |
945 | * | |
946 | * This only allocates the snapshot buffer if it isn't already | |
947 | * allocated - it doesn't also take a snapshot. | |
948 | * | |
949 | * This is meant to be used in cases where the snapshot buffer needs | |
950 | * to be set up for events that can't sleep but need to be able to | |
951 | * trigger a snapshot. | |
952 | */ | |
953 | int tracing_alloc_snapshot(void) | |
954 | { | |
955 | struct trace_array *tr = &global_trace; | |
956 | int ret; | |
957 | ||
958 | ret = alloc_snapshot(tr); | |
959 | WARN_ON(ret < 0); | |
960 | ||
961 | return ret; | |
962 | } | |
963 | EXPORT_SYMBOL_GPL(tracing_alloc_snapshot); | |
964 | ||
ad909e21 SRRH |
965 | /** |
966 | * trace_snapshot_alloc - allocate and take a snapshot of the current buffer. | |
967 | * | |
968 | * This is similar to trace_snapshot(), but it will allocate the | |
969 | * snapshot buffer if it isn't already allocated. Use this only | |
970 | * where it is safe to sleep, as the allocation may sleep. | |
971 | * | |
972 | * This causes a swap between the snapshot buffer and the current live | |
973 | * tracing buffer. You can use this to take snapshots of the live | |
974 | * trace when some condition is triggered, but continue to trace. | |
975 | */ | |
976 | void tracing_snapshot_alloc(void) | |
977 | { | |
ad909e21 SRRH |
978 | int ret; |
979 | ||
93e31ffb TZ |
980 | ret = tracing_alloc_snapshot(); |
981 | if (ret < 0) | |
3209cff4 | 982 | return; |
ad909e21 SRRH |
983 | |
984 | tracing_snapshot(); | |
985 | } | |
1b22e382 | 986 | EXPORT_SYMBOL_GPL(tracing_snapshot_alloc); |
ad909e21 SRRH |
987 | #else |
988 | void tracing_snapshot(void) | |
989 | { | |
990 | WARN_ONCE(1, "Snapshot feature not enabled, but internal snapshot used"); | |
991 | } | |
1b22e382 | 992 | EXPORT_SYMBOL_GPL(tracing_snapshot); |
93e31ffb TZ |
993 | int tracing_alloc_snapshot(void) |
994 | { | |
995 | WARN_ONCE(1, "Snapshot feature not enabled, but snapshot allocation used"); | |
996 | return -ENODEV; | |
997 | } | |
998 | EXPORT_SYMBOL_GPL(tracing_alloc_snapshot); | |
ad909e21 SRRH |
999 | void tracing_snapshot_alloc(void) |
1000 | { | |
1001 | /* Give warning */ | |
1002 | tracing_snapshot(); | |
1003 | } | |
1b22e382 | 1004 | EXPORT_SYMBOL_GPL(tracing_snapshot_alloc); |
ad909e21 SRRH |
1005 | #endif /* CONFIG_TRACER_SNAPSHOT */ |
1006 | ||
5280bcef | 1007 | static void tracer_tracing_off(struct trace_array *tr) |
10246fa3 SRRH |
1008 | { |
1009 | if (tr->trace_buffer.buffer) | |
1010 | ring_buffer_record_off(tr->trace_buffer.buffer); | |
1011 | /* | |
1012 | * This flag is looked at when buffers haven't been allocated | |
1013 | * yet, or by some tracers (like irqsoff), that just want to | |
1014 | * know if the ring buffer has been disabled, but it can handle | |
1015 | * races of where it gets disabled but we still do a record. | |
1016 | * As the check is in the fast path of the tracers, it is more | |
1017 | * important to be fast than accurate. | |
1018 | */ | |
1019 | tr->buffer_disabled = 1; | |
1020 | /* Make the flag seen by readers */ | |
1021 | smp_wmb(); | |
1022 | } | |
1023 | ||
499e5470 SR |
1024 | /** |
1025 | * tracing_off - turn off tracing buffers | |
1026 | * | |
1027 | * This function stops the tracing buffers from recording data. | |
1028 | * It does not disable any overhead the tracers themselves may | |
1029 | * be causing. This function simply causes all recording to | |
1030 | * the ring buffers to fail. | |
1031 | */ | |
1032 | void tracing_off(void) | |
1033 | { | |
10246fa3 | 1034 | tracer_tracing_off(&global_trace); |
499e5470 SR |
1035 | } |
1036 | EXPORT_SYMBOL_GPL(tracing_off); | |
1037 | ||
de7edd31 SRRH |
1038 | void disable_trace_on_warning(void) |
1039 | { | |
1040 | if (__disable_trace_on_warning) | |
1041 | tracing_off(); | |
1042 | } | |
1043 | ||
10246fa3 SRRH |
1044 | /** |
1045 | * tracer_tracing_is_on - show real state of ring buffer enabled | |
1046 | * @tr : the trace array to know if ring buffer is enabled | |
1047 | * | |
1048 | * Shows real state of the ring buffer if it is enabled or not. | |
1049 | */ | |
e7c15cd8 | 1050 | int tracer_tracing_is_on(struct trace_array *tr) |
10246fa3 SRRH |
1051 | { |
1052 | if (tr->trace_buffer.buffer) | |
1053 | return ring_buffer_record_is_on(tr->trace_buffer.buffer); | |
1054 | return !tr->buffer_disabled; | |
1055 | } | |
1056 | ||
499e5470 SR |
1057 | /** |
1058 | * tracing_is_on - show state of ring buffers enabled | |
1059 | */ | |
1060 | int tracing_is_on(void) | |
1061 | { | |
10246fa3 | 1062 | return tracer_tracing_is_on(&global_trace); |
499e5470 SR |
1063 | } |
1064 | EXPORT_SYMBOL_GPL(tracing_is_on); | |
1065 | ||
3928a8a2 | 1066 | static int __init set_buf_size(char *str) |
bc0c38d1 | 1067 | { |
3928a8a2 | 1068 | unsigned long buf_size; |
c6caeeb1 | 1069 | |
bc0c38d1 SR |
1070 | if (!str) |
1071 | return 0; | |
9d612bef | 1072 | buf_size = memparse(str, &str); |
c6caeeb1 | 1073 | /* nr_entries can not be zero */ |
9d612bef | 1074 | if (buf_size == 0) |
c6caeeb1 | 1075 | return 0; |
3928a8a2 | 1076 | trace_buf_size = buf_size; |
bc0c38d1 SR |
1077 | return 1; |
1078 | } | |
3928a8a2 | 1079 | __setup("trace_buf_size=", set_buf_size); |
bc0c38d1 | 1080 | |
0e950173 TB |
1081 | static int __init set_tracing_thresh(char *str) |
1082 | { | |
87abb3b1 | 1083 | unsigned long threshold; |
0e950173 TB |
1084 | int ret; |
1085 | ||
1086 | if (!str) | |
1087 | return 0; | |
bcd83ea6 | 1088 | ret = kstrtoul(str, 0, &threshold); |
0e950173 TB |
1089 | if (ret < 0) |
1090 | return 0; | |
87abb3b1 | 1091 | tracing_thresh = threshold * 1000; |
0e950173 TB |
1092 | return 1; |
1093 | } | |
1094 | __setup("tracing_thresh=", set_tracing_thresh); | |
1095 | ||
57f50be1 SR |
1096 | unsigned long nsecs_to_usecs(unsigned long nsecs) |
1097 | { | |
1098 | return nsecs / 1000; | |
1099 | } | |
1100 | ||
a3418a36 SRRH |
1101 | /* |
1102 | * TRACE_FLAGS is defined as a tuple matching bit masks with strings. | |
1103 | * It uses C(a, b) where 'a' is the enum name and 'b' is the string that | |
1104 | * matches it. By defining "C(a, b) b", TRACE_FLAGS becomes a list | |
1105 | * of strings in the order that the enums were defined. | |
1106 | */ | |
1107 | #undef C | |
1108 | #define C(a, b) b | |
1109 | ||
4fcdae83 | 1110 | /* These must match the bit postions in trace_iterator_flags */ |
bc0c38d1 | 1111 | static const char *trace_options[] = { |
a3418a36 | 1112 | TRACE_FLAGS |
bc0c38d1 SR |
1113 | NULL |
1114 | }; | |
1115 | ||
5079f326 Z |
1116 | static struct { |
1117 | u64 (*func)(void); | |
1118 | const char *name; | |
8be0709f | 1119 | int in_ns; /* is this clock in nanoseconds? */ |
5079f326 | 1120 | } trace_clocks[] = { |
1b3e5c09 TG |
1121 | { trace_clock_local, "local", 1 }, |
1122 | { trace_clock_global, "global", 1 }, | |
1123 | { trace_clock_counter, "counter", 0 }, | |
e7fda6c4 | 1124 | { trace_clock_jiffies, "uptime", 0 }, |
1b3e5c09 TG |
1125 | { trace_clock, "perf", 1 }, |
1126 | { ktime_get_mono_fast_ns, "mono", 1 }, | |
aabfa5f2 | 1127 | { ktime_get_raw_fast_ns, "mono_raw", 1 }, |
8cbd9cc6 | 1128 | ARCH_TRACE_CLOCKS |
5079f326 Z |
1129 | }; |
1130 | ||
b63f39ea | 1131 | /* |
1132 | * trace_parser_get_init - gets the buffer for trace parser | |
1133 | */ | |
1134 | int trace_parser_get_init(struct trace_parser *parser, int size) | |
1135 | { | |
1136 | memset(parser, 0, sizeof(*parser)); | |
1137 | ||
1138 | parser->buffer = kmalloc(size, GFP_KERNEL); | |
1139 | if (!parser->buffer) | |
1140 | return 1; | |
1141 | ||
1142 | parser->size = size; | |
1143 | return 0; | |
1144 | } | |
1145 | ||
1146 | /* | |
1147 | * trace_parser_put - frees the buffer for trace parser | |
1148 | */ | |
1149 | void trace_parser_put(struct trace_parser *parser) | |
1150 | { | |
1151 | kfree(parser->buffer); | |
1152 | } | |
1153 | ||
1154 | /* | |
1155 | * trace_get_user - reads the user input string separated by space | |
1156 | * (matched by isspace(ch)) | |
1157 | * | |
1158 | * For each string found the 'struct trace_parser' is updated, | |
1159 | * and the function returns. | |
1160 | * | |
1161 | * Returns number of bytes read. | |
1162 | * | |
1163 | * See kernel/trace/trace.h for 'struct trace_parser' details. | |
1164 | */ | |
1165 | int trace_get_user(struct trace_parser *parser, const char __user *ubuf, | |
1166 | size_t cnt, loff_t *ppos) | |
1167 | { | |
1168 | char ch; | |
1169 | size_t read = 0; | |
1170 | ssize_t ret; | |
1171 | ||
1172 | if (!*ppos) | |
1173 | trace_parser_clear(parser); | |
1174 | ||
1175 | ret = get_user(ch, ubuf++); | |
1176 | if (ret) | |
1177 | goto out; | |
1178 | ||
1179 | read++; | |
1180 | cnt--; | |
1181 | ||
1182 | /* | |
1183 | * The parser is not finished with the last write, | |
1184 | * continue reading the user input without skipping spaces. | |
1185 | */ | |
1186 | if (!parser->cont) { | |
1187 | /* skip white space */ | |
1188 | while (cnt && isspace(ch)) { | |
1189 | ret = get_user(ch, ubuf++); | |
1190 | if (ret) | |
1191 | goto out; | |
1192 | read++; | |
1193 | cnt--; | |
1194 | } | |
1195 | ||
1196 | /* only spaces were written */ | |
1197 | if (isspace(ch)) { | |
1198 | *ppos += read; | |
1199 | ret = read; | |
1200 | goto out; | |
1201 | } | |
1202 | ||
1203 | parser->idx = 0; | |
1204 | } | |
1205 | ||
1206 | /* read the non-space input */ | |
1207 | while (cnt && !isspace(ch)) { | |
3c235a33 | 1208 | if (parser->idx < parser->size - 1) |
b63f39ea | 1209 | parser->buffer[parser->idx++] = ch; |
1210 | else { | |
1211 | ret = -EINVAL; | |
1212 | goto out; | |
1213 | } | |
1214 | ret = get_user(ch, ubuf++); | |
1215 | if (ret) | |
1216 | goto out; | |
1217 | read++; | |
1218 | cnt--; | |
1219 | } | |
1220 | ||
1221 | /* We either got finished input or we have to wait for another call. */ | |
1222 | if (isspace(ch)) { | |
1223 | parser->buffer[parser->idx] = 0; | |
1224 | parser->cont = false; | |
057db848 | 1225 | } else if (parser->idx < parser->size - 1) { |
b63f39ea | 1226 | parser->cont = true; |
1227 | parser->buffer[parser->idx++] = ch; | |
057db848 SR |
1228 | } else { |
1229 | ret = -EINVAL; | |
1230 | goto out; | |
b63f39ea | 1231 | } |
1232 | ||
1233 | *ppos += read; | |
1234 | ret = read; | |
1235 | ||
1236 | out: | |
1237 | return ret; | |
1238 | } | |
1239 | ||
3a161d99 | 1240 | /* TODO add a seq_buf_to_buffer() */ |
b8b94265 | 1241 | static ssize_t trace_seq_to_buffer(struct trace_seq *s, void *buf, size_t cnt) |
3c56819b EGM |
1242 | { |
1243 | int len; | |
3c56819b | 1244 | |
5ac48378 | 1245 | if (trace_seq_used(s) <= s->seq.readpos) |
3c56819b EGM |
1246 | return -EBUSY; |
1247 | ||
5ac48378 | 1248 | len = trace_seq_used(s) - s->seq.readpos; |
3c56819b EGM |
1249 | if (cnt > len) |
1250 | cnt = len; | |
3a161d99 | 1251 | memcpy(buf, s->buffer + s->seq.readpos, cnt); |
3c56819b | 1252 | |
3a161d99 | 1253 | s->seq.readpos += cnt; |
3c56819b EGM |
1254 | return cnt; |
1255 | } | |
1256 | ||
0e950173 TB |
1257 | unsigned long __read_mostly tracing_thresh; |
1258 | ||
5d4a9dba | 1259 | #ifdef CONFIG_TRACER_MAX_TRACE |
5d4a9dba SR |
1260 | /* |
1261 | * Copy the new maximum trace into the separate maximum-trace | |
1262 | * structure. (this way the maximum trace is permanently saved, | |
1263 | * for later retrieval via /sys/kernel/debug/tracing/latency_trace) | |
1264 | */ | |
1265 | static void | |
1266 | __update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) | |
1267 | { | |
12883efb SRRH |
1268 | struct trace_buffer *trace_buf = &tr->trace_buffer; |
1269 | struct trace_buffer *max_buf = &tr->max_buffer; | |
1270 | struct trace_array_cpu *data = per_cpu_ptr(trace_buf->data, cpu); | |
1271 | struct trace_array_cpu *max_data = per_cpu_ptr(max_buf->data, cpu); | |
5d4a9dba | 1272 | |
12883efb SRRH |
1273 | max_buf->cpu = cpu; |
1274 | max_buf->time_start = data->preempt_timestamp; | |
5d4a9dba | 1275 | |
6d9b3fa5 | 1276 | max_data->saved_latency = tr->max_latency; |
8248ac05 SR |
1277 | max_data->critical_start = data->critical_start; |
1278 | max_data->critical_end = data->critical_end; | |
5d4a9dba | 1279 | |
1acaa1b2 | 1280 | memcpy(max_data->comm, tsk->comm, TASK_COMM_LEN); |
8248ac05 | 1281 | max_data->pid = tsk->pid; |
f17a5194 SRRH |
1282 | /* |
1283 | * If tsk == current, then use current_uid(), as that does not use | |
1284 | * RCU. The irq tracer can be called out of RCU scope. | |
1285 | */ | |
1286 | if (tsk == current) | |
1287 | max_data->uid = current_uid(); | |
1288 | else | |
1289 | max_data->uid = task_uid(tsk); | |
1290 | ||
8248ac05 SR |
1291 | max_data->nice = tsk->static_prio - 20 - MAX_RT_PRIO; |
1292 | max_data->policy = tsk->policy; | |
1293 | max_data->rt_priority = tsk->rt_priority; | |
5d4a9dba SR |
1294 | |
1295 | /* record this tasks comm */ | |
1296 | tracing_record_cmdline(tsk); | |
1297 | } | |
1298 | ||
4fcdae83 SR |
1299 | /** |
1300 | * update_max_tr - snapshot all trace buffers from global_trace to max_tr | |
1301 | * @tr: tracer | |
1302 | * @tsk: the task with the latency | |
1303 | * @cpu: The cpu that initiated the trace. | |
1304 | * | |
1305 | * Flip the buffers between the @tr and the max_tr and record information | |
1306 | * about which task was the cause of this latency. | |
1307 | */ | |
e309b41d | 1308 | void |
bc0c38d1 SR |
1309 | update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) |
1310 | { | |
2721e72d | 1311 | struct ring_buffer *buf; |
bc0c38d1 | 1312 | |
2b6080f2 | 1313 | if (tr->stop_count) |
b8de7bd1 SR |
1314 | return; |
1315 | ||
4c11d7ae | 1316 | WARN_ON_ONCE(!irqs_disabled()); |
34600f0e | 1317 | |
45ad21ca | 1318 | if (!tr->allocated_snapshot) { |
debdd57f | 1319 | /* Only the nop tracer should hit this when disabling */ |
2b6080f2 | 1320 | WARN_ON_ONCE(tr->current_trace != &nop_trace); |
34600f0e | 1321 | return; |
debdd57f | 1322 | } |
34600f0e | 1323 | |
0b9b12c1 | 1324 | arch_spin_lock(&tr->max_lock); |
3928a8a2 | 1325 | |
12883efb SRRH |
1326 | buf = tr->trace_buffer.buffer; |
1327 | tr->trace_buffer.buffer = tr->max_buffer.buffer; | |
1328 | tr->max_buffer.buffer = buf; | |
3928a8a2 | 1329 | |
bc0c38d1 | 1330 | __update_max_tr(tr, tsk, cpu); |
0b9b12c1 | 1331 | arch_spin_unlock(&tr->max_lock); |
bc0c38d1 SR |
1332 | } |
1333 | ||
1334 | /** | |
1335 | * update_max_tr_single - only copy one trace over, and reset the rest | |
1336 | * @tr - tracer | |
1337 | * @tsk - task with the latency | |
1338 | * @cpu - the cpu of the buffer to copy. | |
4fcdae83 SR |
1339 | * |
1340 | * Flip the trace of a single CPU buffer between the @tr and the max_tr. | |
bc0c38d1 | 1341 | */ |
e309b41d | 1342 | void |
bc0c38d1 SR |
1343 | update_max_tr_single(struct trace_array *tr, struct task_struct *tsk, int cpu) |
1344 | { | |
3928a8a2 | 1345 | int ret; |
bc0c38d1 | 1346 | |
2b6080f2 | 1347 | if (tr->stop_count) |
b8de7bd1 SR |
1348 | return; |
1349 | ||
4c11d7ae | 1350 | WARN_ON_ONCE(!irqs_disabled()); |
6c24499f | 1351 | if (!tr->allocated_snapshot) { |
2930e04d | 1352 | /* Only the nop tracer should hit this when disabling */ |
9e8529af | 1353 | WARN_ON_ONCE(tr->current_trace != &nop_trace); |
ef710e10 | 1354 | return; |
2930e04d | 1355 | } |
ef710e10 | 1356 | |
0b9b12c1 | 1357 | arch_spin_lock(&tr->max_lock); |
bc0c38d1 | 1358 | |
12883efb | 1359 | ret = ring_buffer_swap_cpu(tr->max_buffer.buffer, tr->trace_buffer.buffer, cpu); |
3928a8a2 | 1360 | |
e8165dbb SR |
1361 | if (ret == -EBUSY) { |
1362 | /* | |
1363 | * We failed to swap the buffer due to a commit taking | |
1364 | * place on this CPU. We fail to record, but we reset | |
1365 | * the max trace buffer (no one writes directly to it) | |
1366 | * and flag that it failed. | |
1367 | */ | |
12883efb | 1368 | trace_array_printk_buf(tr->max_buffer.buffer, _THIS_IP_, |
e8165dbb SR |
1369 | "Failed to swap buffers due to commit in progress\n"); |
1370 | } | |
1371 | ||
e8165dbb | 1372 | WARN_ON_ONCE(ret && ret != -EAGAIN && ret != -EBUSY); |
bc0c38d1 SR |
1373 | |
1374 | __update_max_tr(tr, tsk, cpu); | |
0b9b12c1 | 1375 | arch_spin_unlock(&tr->max_lock); |
bc0c38d1 | 1376 | } |
5d4a9dba | 1377 | #endif /* CONFIG_TRACER_MAX_TRACE */ |
bc0c38d1 | 1378 | |
e30f53aa | 1379 | static int wait_on_pipe(struct trace_iterator *iter, bool full) |
0d5c6e1c | 1380 | { |
15693458 SRRH |
1381 | /* Iterators are static, they should be filled or empty */ |
1382 | if (trace_buffer_iter(iter, iter->cpu_file)) | |
8b8b3683 | 1383 | return 0; |
0d5c6e1c | 1384 | |
e30f53aa RV |
1385 | return ring_buffer_wait(iter->trace_buffer->buffer, iter->cpu_file, |
1386 | full); | |
0d5c6e1c SR |
1387 | } |
1388 | ||
f4e781c0 SRRH |
1389 | #ifdef CONFIG_FTRACE_STARTUP_TEST |
1390 | static int run_tracer_selftest(struct tracer *type) | |
1391 | { | |
1392 | struct trace_array *tr = &global_trace; | |
1393 | struct tracer *saved_tracer = tr->current_trace; | |
1394 | int ret; | |
0d5c6e1c | 1395 | |
f4e781c0 SRRH |
1396 | if (!type->selftest || tracing_selftest_disabled) |
1397 | return 0; | |
0d5c6e1c SR |
1398 | |
1399 | /* | |
f4e781c0 SRRH |
1400 | * Run a selftest on this tracer. |
1401 | * Here we reset the trace buffer, and set the current | |
1402 | * tracer to be this tracer. The tracer can then run some | |
1403 | * internal tracing to verify that everything is in order. | |
1404 | * If we fail, we do not register this tracer. | |
0d5c6e1c | 1405 | */ |
f4e781c0 | 1406 | tracing_reset_online_cpus(&tr->trace_buffer); |
0d5c6e1c | 1407 | |
f4e781c0 SRRH |
1408 | tr->current_trace = type; |
1409 | ||
1410 | #ifdef CONFIG_TRACER_MAX_TRACE | |
1411 | if (type->use_max_tr) { | |
1412 | /* If we expanded the buffers, make sure the max is expanded too */ | |
1413 | if (ring_buffer_expanded) | |
1414 | ring_buffer_resize(tr->max_buffer.buffer, trace_buf_size, | |
1415 | RING_BUFFER_ALL_CPUS); | |
1416 | tr->allocated_snapshot = true; | |
1417 | } | |
1418 | #endif | |
1419 | ||
1420 | /* the test is responsible for initializing and enabling */ | |
1421 | pr_info("Testing tracer %s: ", type->name); | |
1422 | ret = type->selftest(type, tr); | |
1423 | /* the test is responsible for resetting too */ | |
1424 | tr->current_trace = saved_tracer; | |
1425 | if (ret) { | |
1426 | printk(KERN_CONT "FAILED!\n"); | |
1427 | /* Add the warning after printing 'FAILED' */ | |
1428 | WARN_ON(1); | |
1429 | return -1; | |
1430 | } | |
1431 | /* Only reset on passing, to avoid touching corrupted buffers */ | |
1432 | tracing_reset_online_cpus(&tr->trace_buffer); | |
1433 | ||
1434 | #ifdef CONFIG_TRACER_MAX_TRACE | |
1435 | if (type->use_max_tr) { | |
1436 | tr->allocated_snapshot = false; | |
0d5c6e1c | 1437 | |
f4e781c0 SRRH |
1438 | /* Shrink the max buffer again */ |
1439 | if (ring_buffer_expanded) | |
1440 | ring_buffer_resize(tr->max_buffer.buffer, 1, | |
1441 | RING_BUFFER_ALL_CPUS); | |
1442 | } | |
1443 | #endif | |
1444 | ||
1445 | printk(KERN_CONT "PASSED\n"); | |
1446 | return 0; | |
1447 | } | |
1448 | #else | |
1449 | static inline int run_tracer_selftest(struct tracer *type) | |
1450 | { | |
1451 | return 0; | |
0d5c6e1c | 1452 | } |
f4e781c0 | 1453 | #endif /* CONFIG_FTRACE_STARTUP_TEST */ |
0d5c6e1c | 1454 | |
41d9c0be SRRH |
1455 | static void add_tracer_options(struct trace_array *tr, struct tracer *t); |
1456 | ||
a4d1e688 JW |
1457 | static void __init apply_trace_boot_options(void); |
1458 | ||
4fcdae83 SR |
1459 | /** |
1460 | * register_tracer - register a tracer with the ftrace system. | |
1461 | * @type - the plugin for the tracer | |
1462 | * | |
1463 | * Register a new plugin tracer. | |
1464 | */ | |
a4d1e688 | 1465 | int __init register_tracer(struct tracer *type) |
bc0c38d1 SR |
1466 | { |
1467 | struct tracer *t; | |
bc0c38d1 SR |
1468 | int ret = 0; |
1469 | ||
1470 | if (!type->name) { | |
1471 | pr_info("Tracer must have a name\n"); | |
1472 | return -1; | |
1473 | } | |
1474 | ||
24a461d5 | 1475 | if (strlen(type->name) >= MAX_TRACER_SIZE) { |
ee6c2c1b LZ |
1476 | pr_info("Tracer has a name longer than %d\n", MAX_TRACER_SIZE); |
1477 | return -1; | |
1478 | } | |
1479 | ||
bc0c38d1 | 1480 | mutex_lock(&trace_types_lock); |
86fa2f60 | 1481 | |
8e1b82e0 FW |
1482 | tracing_selftest_running = true; |
1483 | ||
bc0c38d1 SR |
1484 | for (t = trace_types; t; t = t->next) { |
1485 | if (strcmp(type->name, t->name) == 0) { | |
1486 | /* already found */ | |
ee6c2c1b | 1487 | pr_info("Tracer %s already registered\n", |
bc0c38d1 SR |
1488 | type->name); |
1489 | ret = -1; | |
1490 | goto out; | |
1491 | } | |
1492 | } | |
1493 | ||
adf9f195 FW |
1494 | if (!type->set_flag) |
1495 | type->set_flag = &dummy_set_flag; | |
d39cdd20 CH |
1496 | if (!type->flags) { |
1497 | /*allocate a dummy tracer_flags*/ | |
1498 | type->flags = kmalloc(sizeof(*type->flags), GFP_KERNEL); | |
c8ca003b CH |
1499 | if (!type->flags) { |
1500 | ret = -ENOMEM; | |
1501 | goto out; | |
1502 | } | |
d39cdd20 CH |
1503 | type->flags->val = 0; |
1504 | type->flags->opts = dummy_tracer_opt; | |
1505 | } else | |
adf9f195 FW |
1506 | if (!type->flags->opts) |
1507 | type->flags->opts = dummy_tracer_opt; | |
6eaaa5d5 | 1508 | |
d39cdd20 CH |
1509 | /* store the tracer for __set_tracer_option */ |
1510 | type->flags->trace = type; | |
1511 | ||
f4e781c0 SRRH |
1512 | ret = run_tracer_selftest(type); |
1513 | if (ret < 0) | |
1514 | goto out; | |
60a11774 | 1515 | |
bc0c38d1 SR |
1516 | type->next = trace_types; |
1517 | trace_types = type; | |
41d9c0be | 1518 | add_tracer_options(&global_trace, type); |
60a11774 | 1519 | |
bc0c38d1 | 1520 | out: |
8e1b82e0 | 1521 | tracing_selftest_running = false; |
bc0c38d1 SR |
1522 | mutex_unlock(&trace_types_lock); |
1523 | ||
dac74940 SR |
1524 | if (ret || !default_bootup_tracer) |
1525 | goto out_unlock; | |
1526 | ||
ee6c2c1b | 1527 | if (strncmp(default_bootup_tracer, type->name, MAX_TRACER_SIZE)) |
dac74940 SR |
1528 | goto out_unlock; |
1529 | ||
1530 | printk(KERN_INFO "Starting tracer '%s'\n", type->name); | |
1531 | /* Do we want this tracer to start on bootup? */ | |
607e2ea1 | 1532 | tracing_set_tracer(&global_trace, type->name); |
dac74940 | 1533 | default_bootup_tracer = NULL; |
a4d1e688 JW |
1534 | |
1535 | apply_trace_boot_options(); | |
1536 | ||
dac74940 | 1537 | /* disable other selftests, since this will break it. */ |
55034cd6 | 1538 | tracing_selftest_disabled = true; |
b2821ae6 | 1539 | #ifdef CONFIG_FTRACE_STARTUP_TEST |
dac74940 SR |
1540 | printk(KERN_INFO "Disabling FTRACE selftests due to running tracer '%s'\n", |
1541 | type->name); | |
b2821ae6 | 1542 | #endif |
b2821ae6 | 1543 | |
dac74940 | 1544 | out_unlock: |
bc0c38d1 SR |
1545 | return ret; |
1546 | } | |
1547 | ||
12883efb | 1548 | void tracing_reset(struct trace_buffer *buf, int cpu) |
f633903a | 1549 | { |
12883efb | 1550 | struct ring_buffer *buffer = buf->buffer; |
f633903a | 1551 | |
a5416411 HT |
1552 | if (!buffer) |
1553 | return; | |
1554 | ||
f633903a SR |
1555 | ring_buffer_record_disable(buffer); |
1556 | ||
1557 | /* Make sure all commits have finished */ | |
1558 | synchronize_sched(); | |
68179686 | 1559 | ring_buffer_reset_cpu(buffer, cpu); |
f633903a SR |
1560 | |
1561 | ring_buffer_record_enable(buffer); | |
1562 | } | |
1563 | ||
12883efb | 1564 | void tracing_reset_online_cpus(struct trace_buffer *buf) |
213cc060 | 1565 | { |
12883efb | 1566 | struct ring_buffer *buffer = buf->buffer; |
213cc060 PE |
1567 | int cpu; |
1568 | ||
a5416411 HT |
1569 | if (!buffer) |
1570 | return; | |
1571 | ||
621968cd SR |
1572 | ring_buffer_record_disable(buffer); |
1573 | ||
1574 | /* Make sure all commits have finished */ | |
1575 | synchronize_sched(); | |
1576 | ||
9457158b | 1577 | buf->time_start = buffer_ftrace_now(buf, buf->cpu); |
213cc060 PE |
1578 | |
1579 | for_each_online_cpu(cpu) | |
68179686 | 1580 | ring_buffer_reset_cpu(buffer, cpu); |
621968cd SR |
1581 | |
1582 | ring_buffer_record_enable(buffer); | |
213cc060 PE |
1583 | } |
1584 | ||
09d8091c | 1585 | /* Must have trace_types_lock held */ |
873c642f | 1586 | void tracing_reset_all_online_cpus(void) |
9456f0fa | 1587 | { |
873c642f SRRH |
1588 | struct trace_array *tr; |
1589 | ||
873c642f | 1590 | list_for_each_entry(tr, &ftrace_trace_arrays, list) { |
12883efb SRRH |
1591 | tracing_reset_online_cpus(&tr->trace_buffer); |
1592 | #ifdef CONFIG_TRACER_MAX_TRACE | |
1593 | tracing_reset_online_cpus(&tr->max_buffer); | |
1594 | #endif | |
873c642f | 1595 | } |
9456f0fa SR |
1596 | } |
1597 | ||
939c7a4f | 1598 | #define SAVED_CMDLINES_DEFAULT 128 |
2c7eea4c | 1599 | #define NO_CMDLINE_MAP UINT_MAX |
edc35bd7 | 1600 | static arch_spinlock_t trace_cmdline_lock = __ARCH_SPIN_LOCK_UNLOCKED; |
939c7a4f YY |
1601 | struct saved_cmdlines_buffer { |
1602 | unsigned map_pid_to_cmdline[PID_MAX_DEFAULT+1]; | |
1603 | unsigned *map_cmdline_to_pid; | |
1604 | unsigned cmdline_num; | |
1605 | int cmdline_idx; | |
1606 | char *saved_cmdlines; | |
1607 | }; | |
1608 | static struct saved_cmdlines_buffer *savedcmd; | |
25b0b44a | 1609 | |
25b0b44a | 1610 | /* temporary disable recording */ |
4fd27358 | 1611 | static atomic_t trace_record_cmdline_disabled __read_mostly; |
bc0c38d1 | 1612 | |
939c7a4f YY |
1613 | static inline char *get_saved_cmdlines(int idx) |
1614 | { | |
1615 | return &savedcmd->saved_cmdlines[idx * TASK_COMM_LEN]; | |
1616 | } | |
1617 | ||
1618 | static inline void set_cmdline(int idx, const char *cmdline) | |
bc0c38d1 | 1619 | { |
939c7a4f YY |
1620 | memcpy(get_saved_cmdlines(idx), cmdline, TASK_COMM_LEN); |
1621 | } | |
1622 | ||
1623 | static int allocate_cmdlines_buffer(unsigned int val, | |
1624 | struct saved_cmdlines_buffer *s) | |
1625 | { | |
1626 | s->map_cmdline_to_pid = kmalloc(val * sizeof(*s->map_cmdline_to_pid), | |
1627 | GFP_KERNEL); | |
1628 | if (!s->map_cmdline_to_pid) | |
1629 | return -ENOMEM; | |
1630 | ||
1631 | s->saved_cmdlines = kmalloc(val * TASK_COMM_LEN, GFP_KERNEL); | |
1632 | if (!s->saved_cmdlines) { | |
1633 | kfree(s->map_cmdline_to_pid); | |
1634 | return -ENOMEM; | |
1635 | } | |
1636 | ||
1637 | s->cmdline_idx = 0; | |
1638 | s->cmdline_num = val; | |
1639 | memset(&s->map_pid_to_cmdline, NO_CMDLINE_MAP, | |
1640 | sizeof(s->map_pid_to_cmdline)); | |
1641 | memset(s->map_cmdline_to_pid, NO_CMDLINE_MAP, | |
1642 | val * sizeof(*s->map_cmdline_to_pid)); | |
1643 | ||
1644 | return 0; | |
1645 | } | |
1646 | ||
1647 | static int trace_create_savedcmd(void) | |
1648 | { | |
1649 | int ret; | |
1650 | ||
a6af8fbf | 1651 | savedcmd = kmalloc(sizeof(*savedcmd), GFP_KERNEL); |
939c7a4f YY |
1652 | if (!savedcmd) |
1653 | return -ENOMEM; | |
1654 | ||
1655 | ret = allocate_cmdlines_buffer(SAVED_CMDLINES_DEFAULT, savedcmd); | |
1656 | if (ret < 0) { | |
1657 | kfree(savedcmd); | |
1658 | savedcmd = NULL; | |
1659 | return -ENOMEM; | |
1660 | } | |
1661 | ||
1662 | return 0; | |
bc0c38d1 SR |
1663 | } |
1664 | ||
b5130b1e CE |
1665 | int is_tracing_stopped(void) |
1666 | { | |
2b6080f2 | 1667 | return global_trace.stop_count; |
b5130b1e CE |
1668 | } |
1669 | ||
0f048701 SR |
1670 | /** |
1671 | * tracing_start - quick start of the tracer | |
1672 | * | |
1673 | * If tracing is enabled but was stopped by tracing_stop, | |
1674 | * this will start the tracer back up. | |
1675 | */ | |
1676 | void tracing_start(void) | |
1677 | { | |
1678 | struct ring_buffer *buffer; | |
1679 | unsigned long flags; | |
1680 | ||
1681 | if (tracing_disabled) | |
1682 | return; | |
1683 | ||
2b6080f2 SR |
1684 | raw_spin_lock_irqsave(&global_trace.start_lock, flags); |
1685 | if (--global_trace.stop_count) { | |
1686 | if (global_trace.stop_count < 0) { | |
b06a8301 SR |
1687 | /* Someone screwed up their debugging */ |
1688 | WARN_ON_ONCE(1); | |
2b6080f2 | 1689 | global_trace.stop_count = 0; |
b06a8301 | 1690 | } |
0f048701 SR |
1691 | goto out; |
1692 | } | |
1693 | ||
a2f80714 | 1694 | /* Prevent the buffers from switching */ |
0b9b12c1 | 1695 | arch_spin_lock(&global_trace.max_lock); |
0f048701 | 1696 | |
12883efb | 1697 | buffer = global_trace.trace_buffer.buffer; |
0f048701 SR |
1698 | if (buffer) |
1699 | ring_buffer_record_enable(buffer); | |
1700 | ||
12883efb SRRH |
1701 | #ifdef CONFIG_TRACER_MAX_TRACE |
1702 | buffer = global_trace.max_buffer.buffer; | |
0f048701 SR |
1703 | if (buffer) |
1704 | ring_buffer_record_enable(buffer); | |
12883efb | 1705 | #endif |
0f048701 | 1706 | |
0b9b12c1 | 1707 | arch_spin_unlock(&global_trace.max_lock); |
a2f80714 | 1708 | |
0f048701 | 1709 | out: |
2b6080f2 SR |
1710 | raw_spin_unlock_irqrestore(&global_trace.start_lock, flags); |
1711 | } | |
1712 | ||
1713 | static void tracing_start_tr(struct trace_array *tr) | |
1714 | { | |
1715 | struct ring_buffer *buffer; | |
1716 | unsigned long flags; | |
1717 | ||
1718 | if (tracing_disabled) | |
1719 | return; | |
1720 | ||
1721 | /* If global, we need to also start the max tracer */ | |
1722 | if (tr->flags & TRACE_ARRAY_FL_GLOBAL) | |
1723 | return tracing_start(); | |
1724 | ||
1725 | raw_spin_lock_irqsave(&tr->start_lock, flags); | |
1726 | ||
1727 | if (--tr->stop_count) { | |
1728 | if (tr->stop_count < 0) { | |
1729 | /* Someone screwed up their debugging */ | |
1730 | WARN_ON_ONCE(1); | |
1731 | tr->stop_count = 0; | |
1732 | } | |
1733 | goto out; | |
1734 | } | |
1735 | ||
12883efb | 1736 | buffer = tr->trace_buffer.buffer; |
2b6080f2 SR |
1737 | if (buffer) |
1738 | ring_buffer_record_enable(buffer); | |
1739 | ||
1740 | out: | |
1741 | raw_spin_unlock_irqrestore(&tr->start_lock, flags); | |
0f048701 SR |
1742 | } |
1743 | ||
1744 | /** | |
1745 | * tracing_stop - quick stop of the tracer | |
1746 | * | |
1747 | * Light weight way to stop tracing. Use in conjunction with | |
1748 | * tracing_start. | |
1749 | */ | |
1750 | void tracing_stop(void) | |
1751 | { | |
1752 | struct ring_buffer *buffer; | |
1753 | unsigned long flags; | |
1754 | ||
2b6080f2 SR |
1755 | raw_spin_lock_irqsave(&global_trace.start_lock, flags); |
1756 | if (global_trace.stop_count++) | |
0f048701 SR |
1757 | goto out; |
1758 | ||
a2f80714 | 1759 | /* Prevent the buffers from switching */ |
0b9b12c1 | 1760 | arch_spin_lock(&global_trace.max_lock); |
a2f80714 | 1761 | |
12883efb | 1762 | buffer = global_trace.trace_buffer.buffer; |
0f048701 SR |
1763 | if (buffer) |
1764 | ring_buffer_record_disable(buffer); | |
1765 | ||
12883efb SRRH |
1766 | #ifdef CONFIG_TRACER_MAX_TRACE |
1767 | buffer = global_trace.max_buffer.buffer; | |
0f048701 SR |
1768 | if (buffer) |
1769 | ring_buffer_record_disable(buffer); | |
12883efb | 1770 | #endif |
0f048701 | 1771 | |
0b9b12c1 | 1772 | arch_spin_unlock(&global_trace.max_lock); |
a2f80714 | 1773 | |
0f048701 | 1774 | out: |
2b6080f2 SR |
1775 | raw_spin_unlock_irqrestore(&global_trace.start_lock, flags); |
1776 | } | |
1777 | ||
1778 | static void tracing_stop_tr(struct trace_array *tr) | |
1779 | { | |
1780 | struct ring_buffer *buffer; | |
1781 | unsigned long flags; | |
1782 | ||
1783 | /* If global, we need to also stop the max tracer */ | |
1784 | if (tr->flags & TRACE_ARRAY_FL_GLOBAL) | |
1785 | return tracing_stop(); | |
1786 | ||
1787 | raw_spin_lock_irqsave(&tr->start_lock, flags); | |
1788 | if (tr->stop_count++) | |
1789 | goto out; | |
1790 | ||
12883efb | 1791 | buffer = tr->trace_buffer.buffer; |
2b6080f2 SR |
1792 | if (buffer) |
1793 | ring_buffer_record_disable(buffer); | |
1794 | ||
1795 | out: | |
1796 | raw_spin_unlock_irqrestore(&tr->start_lock, flags); | |
0f048701 SR |
1797 | } |
1798 | ||
e309b41d | 1799 | void trace_stop_cmdline_recording(void); |
bc0c38d1 | 1800 | |
379cfdac | 1801 | static int trace_save_cmdline(struct task_struct *tsk) |
bc0c38d1 | 1802 | { |
a635cf04 | 1803 | unsigned pid, idx; |
bc0c38d1 SR |
1804 | |
1805 | if (!tsk->pid || unlikely(tsk->pid > PID_MAX_DEFAULT)) | |
379cfdac | 1806 | return 0; |
bc0c38d1 SR |
1807 | |
1808 | /* | |
1809 | * It's not the end of the world if we don't get | |
1810 | * the lock, but we also don't want to spin | |
1811 | * nor do we want to disable interrupts, | |
1812 | * so if we miss here, then better luck next time. | |
1813 | */ | |
0199c4e6 | 1814 | if (!arch_spin_trylock(&trace_cmdline_lock)) |
379cfdac | 1815 | return 0; |
bc0c38d1 | 1816 | |
939c7a4f | 1817 | idx = savedcmd->map_pid_to_cmdline[tsk->pid]; |
2c7eea4c | 1818 | if (idx == NO_CMDLINE_MAP) { |
939c7a4f | 1819 | idx = (savedcmd->cmdline_idx + 1) % savedcmd->cmdline_num; |
bc0c38d1 | 1820 | |
a635cf04 CE |
1821 | /* |
1822 | * Check whether the cmdline buffer at idx has a pid | |
1823 | * mapped. We are going to overwrite that entry so we | |
1824 | * need to clear the map_pid_to_cmdline. Otherwise we | |
1825 | * would read the new comm for the old pid. | |
1826 | */ | |
939c7a4f | 1827 | pid = savedcmd->map_cmdline_to_pid[idx]; |
a635cf04 | 1828 | if (pid != NO_CMDLINE_MAP) |
939c7a4f | 1829 | savedcmd->map_pid_to_cmdline[pid] = NO_CMDLINE_MAP; |
bc0c38d1 | 1830 | |
939c7a4f YY |
1831 | savedcmd->map_cmdline_to_pid[idx] = tsk->pid; |
1832 | savedcmd->map_pid_to_cmdline[tsk->pid] = idx; | |
bc0c38d1 | 1833 | |
939c7a4f | 1834 | savedcmd->cmdline_idx = idx; |
bc0c38d1 SR |
1835 | } |
1836 | ||
939c7a4f | 1837 | set_cmdline(idx, tsk->comm); |
bc0c38d1 | 1838 | |
0199c4e6 | 1839 | arch_spin_unlock(&trace_cmdline_lock); |
379cfdac SRRH |
1840 | |
1841 | return 1; | |
bc0c38d1 SR |
1842 | } |
1843 | ||
4c27e756 | 1844 | static void __trace_find_cmdline(int pid, char comm[]) |
bc0c38d1 | 1845 | { |
bc0c38d1 SR |
1846 | unsigned map; |
1847 | ||
4ca53085 SR |
1848 | if (!pid) { |
1849 | strcpy(comm, "<idle>"); | |
1850 | return; | |
1851 | } | |
bc0c38d1 | 1852 | |
74bf4076 SR |
1853 | if (WARN_ON_ONCE(pid < 0)) { |
1854 | strcpy(comm, "<XXX>"); | |
1855 | return; | |
1856 | } | |
1857 | ||
4ca53085 SR |
1858 | if (pid > PID_MAX_DEFAULT) { |
1859 | strcpy(comm, "<...>"); | |
1860 | return; | |
1861 | } | |
bc0c38d1 | 1862 | |
939c7a4f | 1863 | map = savedcmd->map_pid_to_cmdline[pid]; |
50d88758 | 1864 | if (map != NO_CMDLINE_MAP) |
939c7a4f | 1865 | strcpy(comm, get_saved_cmdlines(map)); |
50d88758 TG |
1866 | else |
1867 | strcpy(comm, "<...>"); | |
4c27e756 SRRH |
1868 | } |
1869 | ||
1870 | void trace_find_cmdline(int pid, char comm[]) | |
1871 | { | |
1872 | preempt_disable(); | |
1873 | arch_spin_lock(&trace_cmdline_lock); | |
1874 | ||
1875 | __trace_find_cmdline(pid, comm); | |
bc0c38d1 | 1876 | |
0199c4e6 | 1877 | arch_spin_unlock(&trace_cmdline_lock); |
5b6045a9 | 1878 | preempt_enable(); |
bc0c38d1 SR |
1879 | } |
1880 | ||
e309b41d | 1881 | void tracing_record_cmdline(struct task_struct *tsk) |
bc0c38d1 | 1882 | { |
0fb9656d | 1883 | if (atomic_read(&trace_record_cmdline_disabled) || !tracing_is_on()) |
bc0c38d1 SR |
1884 | return; |
1885 | ||
7ffbd48d SR |
1886 | if (!__this_cpu_read(trace_cmdline_save)) |
1887 | return; | |
1888 | ||
379cfdac SRRH |
1889 | if (trace_save_cmdline(tsk)) |
1890 | __this_cpu_write(trace_cmdline_save, false); | |
bc0c38d1 SR |
1891 | } |
1892 | ||
45dcd8b8 | 1893 | void |
38697053 SR |
1894 | tracing_generic_entry_update(struct trace_entry *entry, unsigned long flags, |
1895 | int pc) | |
bc0c38d1 SR |
1896 | { |
1897 | struct task_struct *tsk = current; | |
bc0c38d1 | 1898 | |
777e208d SR |
1899 | entry->preempt_count = pc & 0xff; |
1900 | entry->pid = (tsk) ? tsk->pid : 0; | |
1901 | entry->flags = | |
9244489a | 1902 | #ifdef CONFIG_TRACE_IRQFLAGS_SUPPORT |
2e2ca155 | 1903 | (irqs_disabled_flags(flags) ? TRACE_FLAG_IRQS_OFF : 0) | |
9244489a SR |
1904 | #else |
1905 | TRACE_FLAG_IRQS_NOSUPPORT | | |
1906 | #endif | |
7e6867bf | 1907 | ((pc & NMI_MASK ) ? TRACE_FLAG_NMI : 0) | |
bc0c38d1 SR |
1908 | ((pc & HARDIRQ_MASK) ? TRACE_FLAG_HARDIRQ : 0) | |
1909 | ((pc & SOFTIRQ_MASK) ? TRACE_FLAG_SOFTIRQ : 0) | | |
e5137b50 PZ |
1910 | (tif_need_resched() ? TRACE_FLAG_NEED_RESCHED : 0) | |
1911 | (test_preempt_need_resched() ? TRACE_FLAG_PREEMPT_RESCHED : 0); | |
bc0c38d1 | 1912 | } |
f413cdb8 | 1913 | EXPORT_SYMBOL_GPL(tracing_generic_entry_update); |
bc0c38d1 | 1914 | |
0fc1b09f SRRH |
1915 | static __always_inline void |
1916 | trace_event_setup(struct ring_buffer_event *event, | |
1917 | int type, unsigned long flags, int pc) | |
1918 | { | |
1919 | struct trace_entry *ent = ring_buffer_event_data(event); | |
1920 | ||
1921 | tracing_generic_entry_update(ent, flags, pc); | |
1922 | ent->type = type; | |
1923 | } | |
1924 | ||
e77405ad SR |
1925 | struct ring_buffer_event * |
1926 | trace_buffer_lock_reserve(struct ring_buffer *buffer, | |
1927 | int type, | |
1928 | unsigned long len, | |
1929 | unsigned long flags, int pc) | |
51a763dd ACM |
1930 | { |
1931 | struct ring_buffer_event *event; | |
1932 | ||
e77405ad | 1933 | event = ring_buffer_lock_reserve(buffer, len); |
0fc1b09f SRRH |
1934 | if (event != NULL) |
1935 | trace_event_setup(event, type, flags, pc); | |
1936 | ||
1937 | return event; | |
1938 | } | |
1939 | ||
1940 | DEFINE_PER_CPU(struct ring_buffer_event *, trace_buffered_event); | |
1941 | DEFINE_PER_CPU(int, trace_buffered_event_cnt); | |
1942 | static int trace_buffered_event_ref; | |
1943 | ||
1944 | /** | |
1945 | * trace_buffered_event_enable - enable buffering events | |
1946 | * | |
1947 | * When events are being filtered, it is quicker to use a temporary | |
1948 | * buffer to write the event data into if there's a likely chance | |
1949 | * that it will not be committed. The discard of the ring buffer | |
1950 | * is not as fast as committing, and is much slower than copying | |
1951 | * a commit. | |
1952 | * | |
1953 | * When an event is to be filtered, allocate per cpu buffers to | |
1954 | * write the event data into, and if the event is filtered and discarded | |
1955 | * it is simply dropped, otherwise, the entire data is to be committed | |
1956 | * in one shot. | |
1957 | */ | |
1958 | void trace_buffered_event_enable(void) | |
1959 | { | |
1960 | struct ring_buffer_event *event; | |
1961 | struct page *page; | |
1962 | int cpu; | |
51a763dd | 1963 | |
0fc1b09f SRRH |
1964 | WARN_ON_ONCE(!mutex_is_locked(&event_mutex)); |
1965 | ||
1966 | if (trace_buffered_event_ref++) | |
1967 | return; | |
1968 | ||
1969 | for_each_tracing_cpu(cpu) { | |
1970 | page = alloc_pages_node(cpu_to_node(cpu), | |
1971 | GFP_KERNEL | __GFP_NORETRY, 0); | |
1972 | if (!page) | |
1973 | goto failed; | |
1974 | ||
1975 | event = page_address(page); | |
1976 | memset(event, 0, sizeof(*event)); | |
1977 | ||
1978 | per_cpu(trace_buffered_event, cpu) = event; | |
1979 | ||
1980 | preempt_disable(); | |
1981 | if (cpu == smp_processor_id() && | |
1982 | this_cpu_read(trace_buffered_event) != | |
1983 | per_cpu(trace_buffered_event, cpu)) | |
1984 | WARN_ON_ONCE(1); | |
1985 | preempt_enable(); | |
51a763dd ACM |
1986 | } |
1987 | ||
0fc1b09f SRRH |
1988 | return; |
1989 | failed: | |
1990 | trace_buffered_event_disable(); | |
1991 | } | |
1992 | ||
1993 | static void enable_trace_buffered_event(void *data) | |
1994 | { | |
1995 | /* Probably not needed, but do it anyway */ | |
1996 | smp_rmb(); | |
1997 | this_cpu_dec(trace_buffered_event_cnt); | |
1998 | } | |
1999 | ||
2000 | static void disable_trace_buffered_event(void *data) | |
2001 | { | |
2002 | this_cpu_inc(trace_buffered_event_cnt); | |
2003 | } | |
2004 | ||
2005 | /** | |
2006 | * trace_buffered_event_disable - disable buffering events | |
2007 | * | |
2008 | * When a filter is removed, it is faster to not use the buffered | |
2009 | * events, and to commit directly into the ring buffer. Free up | |
2010 | * the temp buffers when there are no more users. This requires | |
2011 | * special synchronization with current events. | |
2012 | */ | |
2013 | void trace_buffered_event_disable(void) | |
2014 | { | |
2015 | int cpu; | |
2016 | ||
2017 | WARN_ON_ONCE(!mutex_is_locked(&event_mutex)); | |
2018 | ||
2019 | if (WARN_ON_ONCE(!trace_buffered_event_ref)) | |
2020 | return; | |
2021 | ||
2022 | if (--trace_buffered_event_ref) | |
2023 | return; | |
2024 | ||
2025 | preempt_disable(); | |
2026 | /* For each CPU, set the buffer as used. */ | |
2027 | smp_call_function_many(tracing_buffer_mask, | |
2028 | disable_trace_buffered_event, NULL, 1); | |
2029 | preempt_enable(); | |
2030 | ||
2031 | /* Wait for all current users to finish */ | |
2032 | synchronize_sched(); | |
2033 | ||
2034 | for_each_tracing_cpu(cpu) { | |
2035 | free_page((unsigned long)per_cpu(trace_buffered_event, cpu)); | |
2036 | per_cpu(trace_buffered_event, cpu) = NULL; | |
2037 | } | |
2038 | /* | |
2039 | * Make sure trace_buffered_event is NULL before clearing | |
2040 | * trace_buffered_event_cnt. | |
2041 | */ | |
2042 | smp_wmb(); | |
2043 | ||
2044 | preempt_disable(); | |
2045 | /* Do the work on each cpu */ | |
2046 | smp_call_function_many(tracing_buffer_mask, | |
2047 | enable_trace_buffered_event, NULL, 1); | |
2048 | preempt_enable(); | |
51a763dd | 2049 | } |
51a763dd | 2050 | |
7ffbd48d SR |
2051 | void |
2052 | __buffer_unlock_commit(struct ring_buffer *buffer, struct ring_buffer_event *event) | |
2053 | { | |
2054 | __this_cpu_write(trace_cmdline_save, true); | |
0fc1b09f SRRH |
2055 | |
2056 | /* If this is the temp buffer, we need to commit fully */ | |
2057 | if (this_cpu_read(trace_buffered_event) == event) { | |
2058 | /* Length is in event->array[0] */ | |
2059 | ring_buffer_write(buffer, event->array[0], &event->array[1]); | |
2060 | /* Release the temp buffer */ | |
2061 | this_cpu_dec(trace_buffered_event_cnt); | |
2062 | } else | |
2063 | ring_buffer_unlock_commit(buffer, event); | |
7ffbd48d SR |
2064 | } |
2065 | ||
2c4a33ab SRRH |
2066 | static struct ring_buffer *temp_buffer; |
2067 | ||
ccb469a1 SR |
2068 | struct ring_buffer_event * |
2069 | trace_event_buffer_lock_reserve(struct ring_buffer **current_rb, | |
7f1d2f82 | 2070 | struct trace_event_file *trace_file, |
ccb469a1 SR |
2071 | int type, unsigned long len, |
2072 | unsigned long flags, int pc) | |
2073 | { | |
2c4a33ab | 2074 | struct ring_buffer_event *entry; |
0fc1b09f | 2075 | int val; |
2c4a33ab | 2076 | |
7f1d2f82 | 2077 | *current_rb = trace_file->tr->trace_buffer.buffer; |
0fc1b09f SRRH |
2078 | |
2079 | if ((trace_file->flags & | |
2080 | (EVENT_FILE_FL_SOFT_DISABLED | EVENT_FILE_FL_FILTERED)) && | |
2081 | (entry = this_cpu_read(trace_buffered_event))) { | |
2082 | /* Try to use the per cpu buffer first */ | |
2083 | val = this_cpu_inc_return(trace_buffered_event_cnt); | |
2084 | if (val == 1) { | |
2085 | trace_event_setup(entry, type, flags, pc); | |
2086 | entry->array[0] = len; | |
2087 | return entry; | |
2088 | } | |
2089 | this_cpu_dec(trace_buffered_event_cnt); | |
2090 | } | |
2091 | ||
2c4a33ab | 2092 | entry = trace_buffer_lock_reserve(*current_rb, |
ccb469a1 | 2093 | type, len, flags, pc); |
2c4a33ab SRRH |
2094 | /* |
2095 | * If tracing is off, but we have triggers enabled | |
2096 | * we still need to look at the event data. Use the temp_buffer | |
2097 | * to store the trace event for the tigger to use. It's recusive | |
2098 | * safe and will not be recorded anywhere. | |
2099 | */ | |
5d6ad960 | 2100 | if (!entry && trace_file->flags & EVENT_FILE_FL_TRIGGER_COND) { |
2c4a33ab SRRH |
2101 | *current_rb = temp_buffer; |
2102 | entry = trace_buffer_lock_reserve(*current_rb, | |
2103 | type, len, flags, pc); | |
2104 | } | |
2105 | return entry; | |
ccb469a1 SR |
2106 | } |
2107 | EXPORT_SYMBOL_GPL(trace_event_buffer_lock_reserve); | |
2108 | ||
b7f0c959 SRRH |
2109 | void trace_buffer_unlock_commit_regs(struct trace_array *tr, |
2110 | struct ring_buffer *buffer, | |
0d5c6e1c SR |
2111 | struct ring_buffer_event *event, |
2112 | unsigned long flags, int pc, | |
2113 | struct pt_regs *regs) | |
1fd8df2c | 2114 | { |
7ffbd48d | 2115 | __buffer_unlock_commit(buffer, event); |
1fd8df2c | 2116 | |
be54f69c SRRH |
2117 | /* |
2118 | * If regs is not set, then skip the following callers: | |
2119 | * trace_buffer_unlock_commit_regs | |
2120 | * event_trigger_unlock_commit | |
2121 | * trace_event_buffer_commit | |
2122 | * trace_event_raw_event_sched_switch | |
2123 | * Note, we can still get here via blktrace, wakeup tracer | |
2124 | * and mmiotrace, but that's ok if they lose a function or | |
2125 | * two. They are that meaningful. | |
2126 | */ | |
2127 | ftrace_trace_stack(tr, buffer, flags, regs ? 0 : 4, pc, regs); | |
1fd8df2c MH |
2128 | ftrace_trace_userstack(buffer, flags, pc); |
2129 | } | |
1fd8df2c | 2130 | |
e309b41d | 2131 | void |
7be42151 | 2132 | trace_function(struct trace_array *tr, |
38697053 SR |
2133 | unsigned long ip, unsigned long parent_ip, unsigned long flags, |
2134 | int pc) | |
bc0c38d1 | 2135 | { |
2425bcb9 | 2136 | struct trace_event_call *call = &event_function; |
12883efb | 2137 | struct ring_buffer *buffer = tr->trace_buffer.buffer; |
3928a8a2 | 2138 | struct ring_buffer_event *event; |
777e208d | 2139 | struct ftrace_entry *entry; |
bc0c38d1 | 2140 | |
e77405ad | 2141 | event = trace_buffer_lock_reserve(buffer, TRACE_FN, sizeof(*entry), |
51a763dd | 2142 | flags, pc); |
3928a8a2 SR |
2143 | if (!event) |
2144 | return; | |
2145 | entry = ring_buffer_event_data(event); | |
777e208d SR |
2146 | entry->ip = ip; |
2147 | entry->parent_ip = parent_ip; | |
e1112b4d | 2148 | |
f306cc82 | 2149 | if (!call_filter_check_discard(call, entry, buffer, event)) |
7ffbd48d | 2150 | __buffer_unlock_commit(buffer, event); |
bc0c38d1 SR |
2151 | } |
2152 | ||
c0a0d0d3 | 2153 | #ifdef CONFIG_STACKTRACE |
4a9bd3f1 SR |
2154 | |
2155 | #define FTRACE_STACK_MAX_ENTRIES (PAGE_SIZE / sizeof(unsigned long)) | |
2156 | struct ftrace_stack { | |
2157 | unsigned long calls[FTRACE_STACK_MAX_ENTRIES]; | |
2158 | }; | |
2159 | ||
2160 | static DEFINE_PER_CPU(struct ftrace_stack, ftrace_stack); | |
2161 | static DEFINE_PER_CPU(int, ftrace_stack_reserve); | |
2162 | ||
e77405ad | 2163 | static void __ftrace_trace_stack(struct ring_buffer *buffer, |
53614991 | 2164 | unsigned long flags, |
1fd8df2c | 2165 | int skip, int pc, struct pt_regs *regs) |
86387f7e | 2166 | { |
2425bcb9 | 2167 | struct trace_event_call *call = &event_kernel_stack; |
3928a8a2 | 2168 | struct ring_buffer_event *event; |
777e208d | 2169 | struct stack_entry *entry; |
86387f7e | 2170 | struct stack_trace trace; |
4a9bd3f1 SR |
2171 | int use_stack; |
2172 | int size = FTRACE_STACK_ENTRIES; | |
2173 | ||
2174 | trace.nr_entries = 0; | |
2175 | trace.skip = skip; | |
2176 | ||
be54f69c SRRH |
2177 | /* |
2178 | * Add two, for this function and the call to save_stack_trace() | |
2179 | * If regs is set, then these functions will not be in the way. | |
2180 | */ | |
2181 | if (!regs) | |
2182 | trace.skip += 2; | |
2183 | ||
4a9bd3f1 SR |
2184 | /* |
2185 | * Since events can happen in NMIs there's no safe way to | |
2186 | * use the per cpu ftrace_stacks. We reserve it and if an interrupt | |
2187 | * or NMI comes in, it will just have to use the default | |
2188 | * FTRACE_STACK_SIZE. | |
2189 | */ | |
2190 | preempt_disable_notrace(); | |
2191 | ||
82146529 | 2192 | use_stack = __this_cpu_inc_return(ftrace_stack_reserve); |
4a9bd3f1 SR |
2193 | /* |
2194 | * We don't need any atomic variables, just a barrier. | |
2195 | * If an interrupt comes in, we don't care, because it would | |
2196 | * have exited and put the counter back to what we want. | |
2197 | * We just need a barrier to keep gcc from moving things | |
2198 | * around. | |
2199 | */ | |
2200 | barrier(); | |
2201 | if (use_stack == 1) { | |
bdffd893 | 2202 | trace.entries = this_cpu_ptr(ftrace_stack.calls); |
4a9bd3f1 SR |
2203 | trace.max_entries = FTRACE_STACK_MAX_ENTRIES; |
2204 | ||
2205 | if (regs) | |
2206 | save_stack_trace_regs(regs, &trace); | |
2207 | else | |
2208 | save_stack_trace(&trace); | |
2209 | ||
2210 | if (trace.nr_entries > size) | |
2211 | size = trace.nr_entries; | |
2212 | } else | |
2213 | /* From now on, use_stack is a boolean */ | |
2214 | use_stack = 0; | |
2215 | ||
2216 | size *= sizeof(unsigned long); | |
86387f7e | 2217 | |
e77405ad | 2218 | event = trace_buffer_lock_reserve(buffer, TRACE_STACK, |
4a9bd3f1 | 2219 | sizeof(*entry) + size, flags, pc); |
3928a8a2 | 2220 | if (!event) |
4a9bd3f1 SR |
2221 | goto out; |
2222 | entry = ring_buffer_event_data(event); | |
86387f7e | 2223 | |
4a9bd3f1 SR |
2224 | memset(&entry->caller, 0, size); |
2225 | ||
2226 | if (use_stack) | |
2227 | memcpy(&entry->caller, trace.entries, | |
2228 | trace.nr_entries * sizeof(unsigned long)); | |
2229 | else { | |
2230 | trace.max_entries = FTRACE_STACK_ENTRIES; | |
2231 | trace.entries = entry->caller; | |
2232 | if (regs) | |
2233 | save_stack_trace_regs(regs, &trace); | |
2234 | else | |
2235 | save_stack_trace(&trace); | |
2236 | } | |
2237 | ||
2238 | entry->size = trace.nr_entries; | |
86387f7e | 2239 | |
f306cc82 | 2240 | if (!call_filter_check_discard(call, entry, buffer, event)) |
7ffbd48d | 2241 | __buffer_unlock_commit(buffer, event); |
4a9bd3f1 SR |
2242 | |
2243 | out: | |
2244 | /* Again, don't let gcc optimize things here */ | |
2245 | barrier(); | |
82146529 | 2246 | __this_cpu_dec(ftrace_stack_reserve); |
4a9bd3f1 SR |
2247 | preempt_enable_notrace(); |
2248 | ||
f0a920d5 IM |
2249 | } |
2250 | ||
2d34f489 SRRH |
2251 | static inline void ftrace_trace_stack(struct trace_array *tr, |
2252 | struct ring_buffer *buffer, | |
73dddbb5 SRRH |
2253 | unsigned long flags, |
2254 | int skip, int pc, struct pt_regs *regs) | |
53614991 | 2255 | { |
2d34f489 | 2256 | if (!(tr->trace_flags & TRACE_ITER_STACKTRACE)) |
53614991 SR |
2257 | return; |
2258 | ||
73dddbb5 | 2259 | __ftrace_trace_stack(buffer, flags, skip, pc, regs); |
53614991 SR |
2260 | } |
2261 | ||
c0a0d0d3 FW |
2262 | void __trace_stack(struct trace_array *tr, unsigned long flags, int skip, |
2263 | int pc) | |
38697053 | 2264 | { |
12883efb | 2265 | __ftrace_trace_stack(tr->trace_buffer.buffer, flags, skip, pc, NULL); |
38697053 SR |
2266 | } |
2267 | ||
03889384 SR |
2268 | /** |
2269 | * trace_dump_stack - record a stack back trace in the trace buffer | |
c142be8e | 2270 | * @skip: Number of functions to skip (helper handlers) |
03889384 | 2271 | */ |
c142be8e | 2272 | void trace_dump_stack(int skip) |
03889384 SR |
2273 | { |
2274 | unsigned long flags; | |
2275 | ||
2276 | if (tracing_disabled || tracing_selftest_running) | |
e36c5458 | 2277 | return; |
03889384 SR |
2278 | |
2279 | local_save_flags(flags); | |
2280 | ||
c142be8e SRRH |
2281 | /* |
2282 | * Skip 3 more, seems to get us at the caller of | |
2283 | * this function. | |
2284 | */ | |
2285 | skip += 3; | |
2286 | __ftrace_trace_stack(global_trace.trace_buffer.buffer, | |
2287 | flags, skip, preempt_count(), NULL); | |
03889384 SR |
2288 | } |
2289 | ||
91e86e56 SR |
2290 | static DEFINE_PER_CPU(int, user_stack_count); |
2291 | ||
e77405ad SR |
2292 | void |
2293 | ftrace_trace_userstack(struct ring_buffer *buffer, unsigned long flags, int pc) | |
02b67518 | 2294 | { |
2425bcb9 | 2295 | struct trace_event_call *call = &event_user_stack; |
8d7c6a96 | 2296 | struct ring_buffer_event *event; |
02b67518 TE |
2297 | struct userstack_entry *entry; |
2298 | struct stack_trace trace; | |
02b67518 | 2299 | |
983f938a | 2300 | if (!(global_trace.trace_flags & TRACE_ITER_USERSTACKTRACE)) |
02b67518 TE |
2301 | return; |
2302 | ||
b6345879 SR |
2303 | /* |
2304 | * NMIs can not handle page faults, even with fix ups. | |
2305 | * The save user stack can (and often does) fault. | |
2306 | */ | |
2307 | if (unlikely(in_nmi())) | |
2308 | return; | |
02b67518 | 2309 | |
91e86e56 SR |
2310 | /* |
2311 | * prevent recursion, since the user stack tracing may | |
2312 | * trigger other kernel events. | |
2313 | */ | |
2314 | preempt_disable(); | |
2315 | if (__this_cpu_read(user_stack_count)) | |
2316 | goto out; | |
2317 | ||
2318 | __this_cpu_inc(user_stack_count); | |
2319 | ||
e77405ad | 2320 | event = trace_buffer_lock_reserve(buffer, TRACE_USER_STACK, |
51a763dd | 2321 | sizeof(*entry), flags, pc); |
02b67518 | 2322 | if (!event) |
1dbd1951 | 2323 | goto out_drop_count; |
02b67518 | 2324 | entry = ring_buffer_event_data(event); |
02b67518 | 2325 | |
48659d31 | 2326 | entry->tgid = current->tgid; |
02b67518 TE |
2327 | memset(&entry->caller, 0, sizeof(entry->caller)); |
2328 | ||
2329 | trace.nr_entries = 0; | |
2330 | trace.max_entries = FTRACE_STACK_ENTRIES; | |
2331 | trace.skip = 0; | |
2332 | trace.entries = entry->caller; | |
2333 | ||
2334 | save_stack_trace_user(&trace); | |
f306cc82 | 2335 | if (!call_filter_check_discard(call, entry, buffer, event)) |
7ffbd48d | 2336 | __buffer_unlock_commit(buffer, event); |
91e86e56 | 2337 | |
1dbd1951 | 2338 | out_drop_count: |
91e86e56 | 2339 | __this_cpu_dec(user_stack_count); |
91e86e56 SR |
2340 | out: |
2341 | preempt_enable(); | |
02b67518 TE |
2342 | } |
2343 | ||
4fd27358 HE |
2344 | #ifdef UNUSED |
2345 | static void __trace_userstack(struct trace_array *tr, unsigned long flags) | |
02b67518 | 2346 | { |
7be42151 | 2347 | ftrace_trace_userstack(tr, flags, preempt_count()); |
02b67518 | 2348 | } |
4fd27358 | 2349 | #endif /* UNUSED */ |
02b67518 | 2350 | |
c0a0d0d3 FW |
2351 | #endif /* CONFIG_STACKTRACE */ |
2352 | ||
07d777fe SR |
2353 | /* created for use with alloc_percpu */ |
2354 | struct trace_buffer_struct { | |
e2ace001 AL |
2355 | int nesting; |
2356 | char buffer[4][TRACE_BUF_SIZE]; | |
07d777fe SR |
2357 | }; |
2358 | ||
2359 | static struct trace_buffer_struct *trace_percpu_buffer; | |
07d777fe SR |
2360 | |
2361 | /* | |
e2ace001 AL |
2362 | * Thise allows for lockless recording. If we're nested too deeply, then |
2363 | * this returns NULL. | |
07d777fe SR |
2364 | */ |
2365 | static char *get_trace_buf(void) | |
2366 | { | |
e2ace001 | 2367 | struct trace_buffer_struct *buffer = this_cpu_ptr(trace_percpu_buffer); |
07d777fe | 2368 | |
e2ace001 | 2369 | if (!buffer || buffer->nesting >= 4) |
07d777fe SR |
2370 | return NULL; |
2371 | ||
e2ace001 AL |
2372 | return &buffer->buffer[buffer->nesting++][0]; |
2373 | } | |
2374 | ||
2375 | static void put_trace_buf(void) | |
2376 | { | |
2377 | this_cpu_dec(trace_percpu_buffer->nesting); | |
07d777fe SR |
2378 | } |
2379 | ||
2380 | static int alloc_percpu_trace_buffer(void) | |
2381 | { | |
2382 | struct trace_buffer_struct *buffers; | |
07d777fe SR |
2383 | |
2384 | buffers = alloc_percpu(struct trace_buffer_struct); | |
e2ace001 AL |
2385 | if (WARN(!buffers, "Could not allocate percpu trace_printk buffer")) |
2386 | return -ENOMEM; | |
07d777fe SR |
2387 | |
2388 | trace_percpu_buffer = buffers; | |
07d777fe | 2389 | return 0; |
07d777fe SR |
2390 | } |
2391 | ||
81698831 SR |
2392 | static int buffers_allocated; |
2393 | ||
07d777fe SR |
2394 | void trace_printk_init_buffers(void) |
2395 | { | |
07d777fe SR |
2396 | if (buffers_allocated) |
2397 | return; | |
2398 | ||
2399 | if (alloc_percpu_trace_buffer()) | |
2400 | return; | |
2401 | ||
2184db46 SR |
2402 | /* trace_printk() is for debug use only. Don't use it in production. */ |
2403 | ||
a395d6a7 JP |
2404 | pr_warn("\n"); |
2405 | pr_warn("**********************************************************\n"); | |
2406 | pr_warn("** NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE **\n"); | |
2407 | pr_warn("** **\n"); | |
2408 | pr_warn("** trace_printk() being used. Allocating extra memory. **\n"); | |
2409 | pr_warn("** **\n"); | |
2410 | pr_warn("** This means that this is a DEBUG kernel and it is **\n"); | |
2411 | pr_warn("** unsafe for production use. **\n"); | |
2412 | pr_warn("** **\n"); | |
2413 | pr_warn("** If you see this message and you are not debugging **\n"); | |
2414 | pr_warn("** the kernel, report this immediately to your vendor! **\n"); | |
2415 | pr_warn("** **\n"); | |
2416 | pr_warn("** NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE **\n"); | |
2417 | pr_warn("**********************************************************\n"); | |
07d777fe | 2418 | |
b382ede6 SR |
2419 | /* Expand the buffers to set size */ |
2420 | tracing_update_buffers(); | |
2421 | ||
07d777fe | 2422 | buffers_allocated = 1; |
81698831 SR |
2423 | |
2424 | /* | |
2425 | * trace_printk_init_buffers() can be called by modules. | |
2426 | * If that happens, then we need to start cmdline recording | |
2427 | * directly here. If the global_trace.buffer is already | |
2428 | * allocated here, then this was called by module code. | |
2429 | */ | |
12883efb | 2430 | if (global_trace.trace_buffer.buffer) |
81698831 SR |
2431 | tracing_start_cmdline_record(); |
2432 | } | |
2433 | ||
2434 | void trace_printk_start_comm(void) | |
2435 | { | |
2436 | /* Start tracing comms if trace printk is set */ | |
2437 | if (!buffers_allocated) | |
2438 | return; | |
2439 | tracing_start_cmdline_record(); | |
2440 | } | |
2441 | ||
2442 | static void trace_printk_start_stop_comm(int enabled) | |
2443 | { | |
2444 | if (!buffers_allocated) | |
2445 | return; | |
2446 | ||
2447 | if (enabled) | |
2448 | tracing_start_cmdline_record(); | |
2449 | else | |
2450 | tracing_stop_cmdline_record(); | |
07d777fe SR |
2451 | } |
2452 | ||
769b0441 | 2453 | /** |
48ead020 | 2454 | * trace_vbprintk - write binary msg to tracing buffer |
769b0441 FW |
2455 | * |
2456 | */ | |
40ce74f1 | 2457 | int trace_vbprintk(unsigned long ip, const char *fmt, va_list args) |
769b0441 | 2458 | { |
2425bcb9 | 2459 | struct trace_event_call *call = &event_bprint; |
769b0441 | 2460 | struct ring_buffer_event *event; |
e77405ad | 2461 | struct ring_buffer *buffer; |
769b0441 | 2462 | struct trace_array *tr = &global_trace; |
48ead020 | 2463 | struct bprint_entry *entry; |
769b0441 | 2464 | unsigned long flags; |
07d777fe SR |
2465 | char *tbuffer; |
2466 | int len = 0, size, pc; | |
769b0441 FW |
2467 | |
2468 | if (unlikely(tracing_selftest_running || tracing_disabled)) | |
2469 | return 0; | |
2470 | ||
2471 | /* Don't pollute graph traces with trace_vprintk internals */ | |
2472 | pause_graph_tracing(); | |
2473 | ||
2474 | pc = preempt_count(); | |
5168ae50 | 2475 | preempt_disable_notrace(); |
769b0441 | 2476 | |
07d777fe SR |
2477 | tbuffer = get_trace_buf(); |
2478 | if (!tbuffer) { | |
2479 | len = 0; | |
e2ace001 | 2480 | goto out_nobuffer; |
07d777fe | 2481 | } |
769b0441 | 2482 | |
07d777fe | 2483 | len = vbin_printf((u32 *)tbuffer, TRACE_BUF_SIZE/sizeof(int), fmt, args); |
769b0441 | 2484 | |
07d777fe SR |
2485 | if (len > TRACE_BUF_SIZE/sizeof(int) || len < 0) |
2486 | goto out; | |
769b0441 | 2487 | |
07d777fe | 2488 | local_save_flags(flags); |
769b0441 | 2489 | size = sizeof(*entry) + sizeof(u32) * len; |
12883efb | 2490 | buffer = tr->trace_buffer.buffer; |
e77405ad SR |
2491 | event = trace_buffer_lock_reserve(buffer, TRACE_BPRINT, size, |
2492 | flags, pc); | |
769b0441 | 2493 | if (!event) |
07d777fe | 2494 | goto out; |
769b0441 FW |
2495 | entry = ring_buffer_event_data(event); |
2496 | entry->ip = ip; | |
769b0441 FW |
2497 | entry->fmt = fmt; |
2498 | ||
07d777fe | 2499 | memcpy(entry->buf, tbuffer, sizeof(u32) * len); |
f306cc82 | 2500 | if (!call_filter_check_discard(call, entry, buffer, event)) { |
7ffbd48d | 2501 | __buffer_unlock_commit(buffer, event); |
2d34f489 | 2502 | ftrace_trace_stack(tr, buffer, flags, 6, pc, NULL); |
d931369b | 2503 | } |
769b0441 | 2504 | |
769b0441 | 2505 | out: |
e2ace001 AL |
2506 | put_trace_buf(); |
2507 | ||
2508 | out_nobuffer: | |
5168ae50 | 2509 | preempt_enable_notrace(); |
769b0441 FW |
2510 | unpause_graph_tracing(); |
2511 | ||
2512 | return len; | |
2513 | } | |
48ead020 FW |
2514 | EXPORT_SYMBOL_GPL(trace_vbprintk); |
2515 | ||
12883efb SRRH |
2516 | static int |
2517 | __trace_array_vprintk(struct ring_buffer *buffer, | |
2518 | unsigned long ip, const char *fmt, va_list args) | |
48ead020 | 2519 | { |
2425bcb9 | 2520 | struct trace_event_call *call = &event_print; |
48ead020 | 2521 | struct ring_buffer_event *event; |
07d777fe | 2522 | int len = 0, size, pc; |
48ead020 | 2523 | struct print_entry *entry; |
07d777fe SR |
2524 | unsigned long flags; |
2525 | char *tbuffer; | |
48ead020 FW |
2526 | |
2527 | if (tracing_disabled || tracing_selftest_running) | |
2528 | return 0; | |
2529 | ||
07d777fe SR |
2530 | /* Don't pollute graph traces with trace_vprintk internals */ |
2531 | pause_graph_tracing(); | |
2532 | ||
48ead020 FW |
2533 | pc = preempt_count(); |
2534 | preempt_disable_notrace(); | |
48ead020 | 2535 | |
07d777fe SR |
2536 | |
2537 | tbuffer = get_trace_buf(); | |
2538 | if (!tbuffer) { | |
2539 | len = 0; | |
e2ace001 | 2540 | goto out_nobuffer; |
07d777fe | 2541 | } |
48ead020 | 2542 | |
3558a5ac | 2543 | len = vscnprintf(tbuffer, TRACE_BUF_SIZE, fmt, args); |
48ead020 | 2544 | |
07d777fe | 2545 | local_save_flags(flags); |
48ead020 | 2546 | size = sizeof(*entry) + len + 1; |
e77405ad | 2547 | event = trace_buffer_lock_reserve(buffer, TRACE_PRINT, size, |
07d777fe | 2548 | flags, pc); |
48ead020 | 2549 | if (!event) |
07d777fe | 2550 | goto out; |
48ead020 | 2551 | entry = ring_buffer_event_data(event); |
c13d2f7c | 2552 | entry->ip = ip; |
48ead020 | 2553 | |
3558a5ac | 2554 | memcpy(&entry->buf, tbuffer, len + 1); |
f306cc82 | 2555 | if (!call_filter_check_discard(call, entry, buffer, event)) { |
7ffbd48d | 2556 | __buffer_unlock_commit(buffer, event); |
2d34f489 | 2557 | ftrace_trace_stack(&global_trace, buffer, flags, 6, pc, NULL); |
d931369b | 2558 | } |
e2ace001 AL |
2559 | |
2560 | out: | |
2561 | put_trace_buf(); | |
2562 | ||
2563 | out_nobuffer: | |
48ead020 | 2564 | preempt_enable_notrace(); |
07d777fe | 2565 | unpause_graph_tracing(); |
48ead020 FW |
2566 | |
2567 | return len; | |
2568 | } | |
659372d3 | 2569 | |
12883efb SRRH |
2570 | int trace_array_vprintk(struct trace_array *tr, |
2571 | unsigned long ip, const char *fmt, va_list args) | |
2572 | { | |
2573 | return __trace_array_vprintk(tr->trace_buffer.buffer, ip, fmt, args); | |
2574 | } | |
2575 | ||
2576 | int trace_array_printk(struct trace_array *tr, | |
2577 | unsigned long ip, const char *fmt, ...) | |
2578 | { | |
2579 | int ret; | |
2580 | va_list ap; | |
2581 | ||
983f938a | 2582 | if (!(global_trace.trace_flags & TRACE_ITER_PRINTK)) |
12883efb SRRH |
2583 | return 0; |
2584 | ||
2585 | va_start(ap, fmt); | |
2586 | ret = trace_array_vprintk(tr, ip, fmt, ap); | |
2587 | va_end(ap); | |
2588 | return ret; | |
2589 | } | |
2590 | ||
2591 | int trace_array_printk_buf(struct ring_buffer *buffer, | |
2592 | unsigned long ip, const char *fmt, ...) | |
2593 | { | |
2594 | int ret; | |
2595 | va_list ap; | |
2596 | ||
983f938a | 2597 | if (!(global_trace.trace_flags & TRACE_ITER_PRINTK)) |
12883efb SRRH |
2598 | return 0; |
2599 | ||
2600 | va_start(ap, fmt); | |
2601 | ret = __trace_array_vprintk(buffer, ip, fmt, ap); | |
2602 | va_end(ap); | |
2603 | return ret; | |
2604 | } | |
2605 | ||
659372d3 SR |
2606 | int trace_vprintk(unsigned long ip, const char *fmt, va_list args) |
2607 | { | |
a813a159 | 2608 | return trace_array_vprintk(&global_trace, ip, fmt, args); |
659372d3 | 2609 | } |
769b0441 FW |
2610 | EXPORT_SYMBOL_GPL(trace_vprintk); |
2611 | ||
e2ac8ef5 | 2612 | static void trace_iterator_increment(struct trace_iterator *iter) |
5a90f577 | 2613 | { |
6d158a81 SR |
2614 | struct ring_buffer_iter *buf_iter = trace_buffer_iter(iter, iter->cpu); |
2615 | ||
5a90f577 | 2616 | iter->idx++; |
6d158a81 SR |
2617 | if (buf_iter) |
2618 | ring_buffer_read(buf_iter, NULL); | |
5a90f577 SR |
2619 | } |
2620 | ||
e309b41d | 2621 | static struct trace_entry * |
bc21b478 SR |
2622 | peek_next_entry(struct trace_iterator *iter, int cpu, u64 *ts, |
2623 | unsigned long *lost_events) | |
dd0e545f | 2624 | { |
3928a8a2 | 2625 | struct ring_buffer_event *event; |
6d158a81 | 2626 | struct ring_buffer_iter *buf_iter = trace_buffer_iter(iter, cpu); |
dd0e545f | 2627 | |
d769041f SR |
2628 | if (buf_iter) |
2629 | event = ring_buffer_iter_peek(buf_iter, ts); | |
2630 | else | |
12883efb | 2631 | event = ring_buffer_peek(iter->trace_buffer->buffer, cpu, ts, |
bc21b478 | 2632 | lost_events); |
d769041f | 2633 | |
4a9bd3f1 SR |
2634 | if (event) { |
2635 | iter->ent_size = ring_buffer_event_length(event); | |
2636 | return ring_buffer_event_data(event); | |
2637 | } | |
2638 | iter->ent_size = 0; | |
2639 | return NULL; | |
dd0e545f | 2640 | } |
d769041f | 2641 | |
dd0e545f | 2642 | static struct trace_entry * |
bc21b478 SR |
2643 | __find_next_entry(struct trace_iterator *iter, int *ent_cpu, |
2644 | unsigned long *missing_events, u64 *ent_ts) | |
bc0c38d1 | 2645 | { |
12883efb | 2646 | struct ring_buffer *buffer = iter->trace_buffer->buffer; |
bc0c38d1 | 2647 | struct trace_entry *ent, *next = NULL; |
aa27497c | 2648 | unsigned long lost_events = 0, next_lost = 0; |
b04cc6b1 | 2649 | int cpu_file = iter->cpu_file; |
3928a8a2 | 2650 | u64 next_ts = 0, ts; |
bc0c38d1 | 2651 | int next_cpu = -1; |
12b5da34 | 2652 | int next_size = 0; |
bc0c38d1 SR |
2653 | int cpu; |
2654 | ||
b04cc6b1 FW |
2655 | /* |
2656 | * If we are in a per_cpu trace file, don't bother by iterating over | |
2657 | * all cpu and peek directly. | |
2658 | */ | |
ae3b5093 | 2659 | if (cpu_file > RING_BUFFER_ALL_CPUS) { |
b04cc6b1 FW |
2660 | if (ring_buffer_empty_cpu(buffer, cpu_file)) |
2661 | return NULL; | |
bc21b478 | 2662 | ent = peek_next_entry(iter, cpu_file, ent_ts, missing_events); |
b04cc6b1 FW |
2663 | if (ent_cpu) |
2664 | *ent_cpu = cpu_file; | |
2665 | ||
2666 | return ent; | |
2667 | } | |
2668 | ||
ab46428c | 2669 | for_each_tracing_cpu(cpu) { |
dd0e545f | 2670 | |
3928a8a2 SR |
2671 | if (ring_buffer_empty_cpu(buffer, cpu)) |
2672 | continue; | |
dd0e545f | 2673 | |
bc21b478 | 2674 | ent = peek_next_entry(iter, cpu, &ts, &lost_events); |
dd0e545f | 2675 | |
cdd31cd2 IM |
2676 | /* |
2677 | * Pick the entry with the smallest timestamp: | |
2678 | */ | |
3928a8a2 | 2679 | if (ent && (!next || ts < next_ts)) { |
bc0c38d1 SR |
2680 | next = ent; |
2681 | next_cpu = cpu; | |
3928a8a2 | 2682 | next_ts = ts; |
bc21b478 | 2683 | next_lost = lost_events; |
12b5da34 | 2684 | next_size = iter->ent_size; |
bc0c38d1 SR |
2685 | } |
2686 | } | |
2687 | ||
12b5da34 SR |
2688 | iter->ent_size = next_size; |
2689 | ||
bc0c38d1 SR |
2690 | if (ent_cpu) |
2691 | *ent_cpu = next_cpu; | |
2692 | ||
3928a8a2 SR |
2693 | if (ent_ts) |
2694 | *ent_ts = next_ts; | |
2695 | ||
bc21b478 SR |
2696 | if (missing_events) |
2697 | *missing_events = next_lost; | |
2698 | ||
bc0c38d1 SR |
2699 | return next; |
2700 | } | |
2701 | ||
dd0e545f | 2702 | /* Find the next real entry, without updating the iterator itself */ |
c4a8e8be FW |
2703 | struct trace_entry *trace_find_next_entry(struct trace_iterator *iter, |
2704 | int *ent_cpu, u64 *ent_ts) | |
bc0c38d1 | 2705 | { |
bc21b478 | 2706 | return __find_next_entry(iter, ent_cpu, NULL, ent_ts); |
dd0e545f SR |
2707 | } |
2708 | ||
2709 | /* Find the next real entry, and increment the iterator to the next entry */ | |
955b61e5 | 2710 | void *trace_find_next_entry_inc(struct trace_iterator *iter) |
dd0e545f | 2711 | { |
bc21b478 SR |
2712 | iter->ent = __find_next_entry(iter, &iter->cpu, |
2713 | &iter->lost_events, &iter->ts); | |
dd0e545f | 2714 | |
3928a8a2 | 2715 | if (iter->ent) |
e2ac8ef5 | 2716 | trace_iterator_increment(iter); |
dd0e545f | 2717 | |
3928a8a2 | 2718 | return iter->ent ? iter : NULL; |
b3806b43 | 2719 | } |
bc0c38d1 | 2720 | |
e309b41d | 2721 | static void trace_consume(struct trace_iterator *iter) |
b3806b43 | 2722 | { |
12883efb | 2723 | ring_buffer_consume(iter->trace_buffer->buffer, iter->cpu, &iter->ts, |
bc21b478 | 2724 | &iter->lost_events); |
bc0c38d1 SR |
2725 | } |
2726 | ||
e309b41d | 2727 | static void *s_next(struct seq_file *m, void *v, loff_t *pos) |
bc0c38d1 SR |
2728 | { |
2729 | struct trace_iterator *iter = m->private; | |
bc0c38d1 | 2730 | int i = (int)*pos; |
4e3c3333 | 2731 | void *ent; |
bc0c38d1 | 2732 | |
a63ce5b3 SR |
2733 | WARN_ON_ONCE(iter->leftover); |
2734 | ||
bc0c38d1 SR |
2735 | (*pos)++; |
2736 | ||
2737 | /* can't go backwards */ | |
2738 | if (iter->idx > i) | |
2739 | return NULL; | |
2740 | ||
2741 | if (iter->idx < 0) | |
955b61e5 | 2742 | ent = trace_find_next_entry_inc(iter); |
bc0c38d1 SR |
2743 | else |
2744 | ent = iter; | |
2745 | ||
2746 | while (ent && iter->idx < i) | |
955b61e5 | 2747 | ent = trace_find_next_entry_inc(iter); |
bc0c38d1 SR |
2748 | |
2749 | iter->pos = *pos; | |
2750 | ||
bc0c38d1 SR |
2751 | return ent; |
2752 | } | |
2753 | ||
955b61e5 | 2754 | void tracing_iter_reset(struct trace_iterator *iter, int cpu) |
2f26ebd5 | 2755 | { |
2f26ebd5 SR |
2756 | struct ring_buffer_event *event; |
2757 | struct ring_buffer_iter *buf_iter; | |
2758 | unsigned long entries = 0; | |
2759 | u64 ts; | |
2760 | ||
12883efb | 2761 | per_cpu_ptr(iter->trace_buffer->data, cpu)->skipped_entries = 0; |
2f26ebd5 | 2762 | |
6d158a81 SR |
2763 | buf_iter = trace_buffer_iter(iter, cpu); |
2764 | if (!buf_iter) | |
2f26ebd5 SR |
2765 | return; |
2766 | ||
2f26ebd5 SR |
2767 | ring_buffer_iter_reset(buf_iter); |
2768 | ||
2769 | /* | |
2770 | * We could have the case with the max latency tracers | |
2771 | * that a reset never took place on a cpu. This is evident | |
2772 | * by the timestamp being before the start of the buffer. | |
2773 | */ | |
2774 | while ((event = ring_buffer_iter_peek(buf_iter, &ts))) { | |
12883efb | 2775 | if (ts >= iter->trace_buffer->time_start) |
2f26ebd5 SR |
2776 | break; |
2777 | entries++; | |
2778 | ring_buffer_read(buf_iter, NULL); | |
2779 | } | |
2780 | ||
12883efb | 2781 | per_cpu_ptr(iter->trace_buffer->data, cpu)->skipped_entries = entries; |
2f26ebd5 SR |
2782 | } |
2783 | ||
d7350c3f | 2784 | /* |
d7350c3f FW |
2785 | * The current tracer is copied to avoid a global locking |
2786 | * all around. | |
2787 | */ | |
bc0c38d1 SR |
2788 | static void *s_start(struct seq_file *m, loff_t *pos) |
2789 | { | |
2790 | struct trace_iterator *iter = m->private; | |
2b6080f2 | 2791 | struct trace_array *tr = iter->tr; |
b04cc6b1 | 2792 | int cpu_file = iter->cpu_file; |
bc0c38d1 SR |
2793 | void *p = NULL; |
2794 | loff_t l = 0; | |
3928a8a2 | 2795 | int cpu; |
bc0c38d1 | 2796 | |
2fd196ec HT |
2797 | /* |
2798 | * copy the tracer to avoid using a global lock all around. | |
2799 | * iter->trace is a copy of current_trace, the pointer to the | |
2800 | * name may be used instead of a strcmp(), as iter->trace->name | |
2801 | * will point to the same string as current_trace->name. | |
2802 | */ | |
bc0c38d1 | 2803 | mutex_lock(&trace_types_lock); |
2b6080f2 SR |
2804 | if (unlikely(tr->current_trace && iter->trace->name != tr->current_trace->name)) |
2805 | *iter->trace = *tr->current_trace; | |
d7350c3f | 2806 | mutex_unlock(&trace_types_lock); |
bc0c38d1 | 2807 | |
12883efb | 2808 | #ifdef CONFIG_TRACER_MAX_TRACE |
debdd57f HT |
2809 | if (iter->snapshot && iter->trace->use_max_tr) |
2810 | return ERR_PTR(-EBUSY); | |
12883efb | 2811 | #endif |
debdd57f HT |
2812 | |
2813 | if (!iter->snapshot) | |
2814 | atomic_inc(&trace_record_cmdline_disabled); | |
bc0c38d1 | 2815 | |
bc0c38d1 SR |
2816 | if (*pos != iter->pos) { |
2817 | iter->ent = NULL; | |
2818 | iter->cpu = 0; | |
2819 | iter->idx = -1; | |
2820 | ||
ae3b5093 | 2821 | if (cpu_file == RING_BUFFER_ALL_CPUS) { |
b04cc6b1 | 2822 | for_each_tracing_cpu(cpu) |
2f26ebd5 | 2823 | tracing_iter_reset(iter, cpu); |
b04cc6b1 | 2824 | } else |
2f26ebd5 | 2825 | tracing_iter_reset(iter, cpu_file); |
bc0c38d1 | 2826 | |
ac91d854 | 2827 | iter->leftover = 0; |
bc0c38d1 SR |
2828 | for (p = iter; p && l < *pos; p = s_next(m, p, &l)) |
2829 | ; | |
2830 | ||
2831 | } else { | |
a63ce5b3 SR |
2832 | /* |
2833 | * If we overflowed the seq_file before, then we want | |
2834 | * to just reuse the trace_seq buffer again. | |
2835 | */ | |
2836 | if (iter->leftover) | |
2837 | p = iter; | |
2838 | else { | |
2839 | l = *pos - 1; | |
2840 | p = s_next(m, p, &l); | |
2841 | } | |
bc0c38d1 SR |
2842 | } |
2843 | ||
4f535968 | 2844 | trace_event_read_lock(); |
7e53bd42 | 2845 | trace_access_lock(cpu_file); |
bc0c38d1 SR |
2846 | return p; |
2847 | } | |
2848 | ||
2849 | static void s_stop(struct seq_file *m, void *p) | |
2850 | { | |
7e53bd42 LJ |
2851 | struct trace_iterator *iter = m->private; |
2852 | ||
12883efb | 2853 | #ifdef CONFIG_TRACER_MAX_TRACE |
debdd57f HT |
2854 | if (iter->snapshot && iter->trace->use_max_tr) |
2855 | return; | |
12883efb | 2856 | #endif |
debdd57f HT |
2857 | |
2858 | if (!iter->snapshot) | |
2859 | atomic_dec(&trace_record_cmdline_disabled); | |
12883efb | 2860 | |
7e53bd42 | 2861 | trace_access_unlock(iter->cpu_file); |
4f535968 | 2862 | trace_event_read_unlock(); |
bc0c38d1 SR |
2863 | } |
2864 | ||
39eaf7ef | 2865 | static void |
12883efb SRRH |
2866 | get_total_entries(struct trace_buffer *buf, |
2867 | unsigned long *total, unsigned long *entries) | |
39eaf7ef SR |
2868 | { |
2869 | unsigned long count; | |
2870 | int cpu; | |
2871 | ||
2872 | *total = 0; | |
2873 | *entries = 0; | |
2874 | ||
2875 | for_each_tracing_cpu(cpu) { | |
12883efb | 2876 | count = ring_buffer_entries_cpu(buf->buffer, cpu); |
39eaf7ef SR |
2877 | /* |
2878 | * If this buffer has skipped entries, then we hold all | |
2879 | * entries for the trace and we need to ignore the | |
2880 | * ones before the time stamp. | |
2881 | */ | |
12883efb SRRH |
2882 | if (per_cpu_ptr(buf->data, cpu)->skipped_entries) { |
2883 | count -= per_cpu_ptr(buf->data, cpu)->skipped_entries; | |
39eaf7ef SR |
2884 | /* total is the same as the entries */ |
2885 | *total += count; | |
2886 | } else | |
2887 | *total += count + | |
12883efb | 2888 | ring_buffer_overrun_cpu(buf->buffer, cpu); |
39eaf7ef SR |
2889 | *entries += count; |
2890 | } | |
2891 | } | |
2892 | ||
e309b41d | 2893 | static void print_lat_help_header(struct seq_file *m) |
bc0c38d1 | 2894 | { |
d79ac28f RV |
2895 | seq_puts(m, "# _------=> CPU# \n" |
2896 | "# / _-----=> irqs-off \n" | |
2897 | "# | / _----=> need-resched \n" | |
2898 | "# || / _---=> hardirq/softirq \n" | |
2899 | "# ||| / _--=> preempt-depth \n" | |
2900 | "# |||| / delay \n" | |
2901 | "# cmd pid ||||| time | caller \n" | |
2902 | "# \\ / ||||| \\ | / \n"); | |
bc0c38d1 SR |
2903 | } |
2904 | ||
12883efb | 2905 | static void print_event_info(struct trace_buffer *buf, struct seq_file *m) |
bc0c38d1 | 2906 | { |
39eaf7ef SR |
2907 | unsigned long total; |
2908 | unsigned long entries; | |
2909 | ||
12883efb | 2910 | get_total_entries(buf, &total, &entries); |
39eaf7ef SR |
2911 | seq_printf(m, "# entries-in-buffer/entries-written: %lu/%lu #P:%d\n", |
2912 | entries, total, num_online_cpus()); | |
2913 | seq_puts(m, "#\n"); | |
2914 | } | |
2915 | ||
12883efb | 2916 | static void print_func_help_header(struct trace_buffer *buf, struct seq_file *m) |
39eaf7ef | 2917 | { |
12883efb | 2918 | print_event_info(buf, m); |
d79ac28f RV |
2919 | seq_puts(m, "# TASK-PID CPU# TIMESTAMP FUNCTION\n" |
2920 | "# | | | | |\n"); | |
bc0c38d1 SR |
2921 | } |
2922 | ||
12883efb | 2923 | static void print_func_help_header_irq(struct trace_buffer *buf, struct seq_file *m) |
77271ce4 | 2924 | { |
12883efb | 2925 | print_event_info(buf, m); |
d79ac28f RV |
2926 | seq_puts(m, "# _-----=> irqs-off\n" |
2927 | "# / _----=> need-resched\n" | |
2928 | "# | / _---=> hardirq/softirq\n" | |
2929 | "# || / _--=> preempt-depth\n" | |
2930 | "# ||| / delay\n" | |
2931 | "# TASK-PID CPU# |||| TIMESTAMP FUNCTION\n" | |
2932 | "# | | | |||| | |\n"); | |
77271ce4 | 2933 | } |
bc0c38d1 | 2934 | |
62b915f1 | 2935 | void |
bc0c38d1 SR |
2936 | print_trace_header(struct seq_file *m, struct trace_iterator *iter) |
2937 | { | |
983f938a | 2938 | unsigned long sym_flags = (global_trace.trace_flags & TRACE_ITER_SYM_MASK); |
12883efb SRRH |
2939 | struct trace_buffer *buf = iter->trace_buffer; |
2940 | struct trace_array_cpu *data = per_cpu_ptr(buf->data, buf->cpu); | |
2b6080f2 | 2941 | struct tracer *type = iter->trace; |
39eaf7ef SR |
2942 | unsigned long entries; |
2943 | unsigned long total; | |
bc0c38d1 SR |
2944 | const char *name = "preemption"; |
2945 | ||
d840f718 | 2946 | name = type->name; |
bc0c38d1 | 2947 | |
12883efb | 2948 | get_total_entries(buf, &total, &entries); |
bc0c38d1 | 2949 | |
888b55dc | 2950 | seq_printf(m, "# %s latency trace v1.1.5 on %s\n", |
bc0c38d1 | 2951 | name, UTS_RELEASE); |
888b55dc | 2952 | seq_puts(m, "# -----------------------------------" |
bc0c38d1 | 2953 | "---------------------------------\n"); |
888b55dc | 2954 | seq_printf(m, "# latency: %lu us, #%lu/%lu, CPU#%d |" |
bc0c38d1 | 2955 | " (M:%s VP:%d, KP:%d, SP:%d HP:%d", |
57f50be1 | 2956 | nsecs_to_usecs(data->saved_latency), |
bc0c38d1 | 2957 | entries, |
4c11d7ae | 2958 | total, |
12883efb | 2959 | buf->cpu, |
bc0c38d1 SR |
2960 | #if defined(CONFIG_PREEMPT_NONE) |
2961 | "server", | |
2962 | #elif defined(CONFIG_PREEMPT_VOLUNTARY) | |
2963 | "desktop", | |
b5c21b45 | 2964 | #elif defined(CONFIG_PREEMPT) |
bc0c38d1 SR |
2965 | "preempt", |
2966 | #else | |
2967 | "unknown", | |
2968 | #endif | |
2969 | /* These are reserved for later use */ | |
2970 | 0, 0, 0, 0); | |
2971 | #ifdef CONFIG_SMP | |
2972 | seq_printf(m, " #P:%d)\n", num_online_cpus()); | |
2973 | #else | |
2974 | seq_puts(m, ")\n"); | |
2975 | #endif | |
888b55dc KM |
2976 | seq_puts(m, "# -----------------\n"); |
2977 | seq_printf(m, "# | task: %.16s-%d " | |
bc0c38d1 | 2978 | "(uid:%d nice:%ld policy:%ld rt_prio:%ld)\n", |
d20b92ab EB |
2979 | data->comm, data->pid, |
2980 | from_kuid_munged(seq_user_ns(m), data->uid), data->nice, | |
bc0c38d1 | 2981 | data->policy, data->rt_priority); |
888b55dc | 2982 | seq_puts(m, "# -----------------\n"); |
bc0c38d1 SR |
2983 | |
2984 | if (data->critical_start) { | |
888b55dc | 2985 | seq_puts(m, "# => started at: "); |
214023c3 SR |
2986 | seq_print_ip_sym(&iter->seq, data->critical_start, sym_flags); |
2987 | trace_print_seq(m, &iter->seq); | |
888b55dc | 2988 | seq_puts(m, "\n# => ended at: "); |
214023c3 SR |
2989 | seq_print_ip_sym(&iter->seq, data->critical_end, sym_flags); |
2990 | trace_print_seq(m, &iter->seq); | |
8248ac05 | 2991 | seq_puts(m, "\n#\n"); |
bc0c38d1 SR |
2992 | } |
2993 | ||
888b55dc | 2994 | seq_puts(m, "#\n"); |
bc0c38d1 SR |
2995 | } |
2996 | ||
a309720c SR |
2997 | static void test_cpu_buff_start(struct trace_iterator *iter) |
2998 | { | |
2999 | struct trace_seq *s = &iter->seq; | |
983f938a | 3000 | struct trace_array *tr = iter->tr; |
a309720c | 3001 | |
983f938a | 3002 | if (!(tr->trace_flags & TRACE_ITER_ANNOTATE)) |
12ef7d44 SR |
3003 | return; |
3004 | ||
3005 | if (!(iter->iter_flags & TRACE_FILE_ANNOTATE)) | |
3006 | return; | |
3007 | ||
919cd979 | 3008 | if (iter->started && cpumask_test_cpu(iter->cpu, iter->started)) |
a309720c SR |
3009 | return; |
3010 | ||
12883efb | 3011 | if (per_cpu_ptr(iter->trace_buffer->data, iter->cpu)->skipped_entries) |
2f26ebd5 SR |
3012 | return; |
3013 | ||
919cd979 SL |
3014 | if (iter->started) |
3015 | cpumask_set_cpu(iter->cpu, iter->started); | |
b0dfa978 FW |
3016 | |
3017 | /* Don't print started cpu buffer for the first entry of the trace */ | |
3018 | if (iter->idx > 1) | |
3019 | trace_seq_printf(s, "##### CPU %u buffer started ####\n", | |
3020 | iter->cpu); | |
a309720c SR |
3021 | } |
3022 | ||
2c4f035f | 3023 | static enum print_line_t print_trace_fmt(struct trace_iterator *iter) |
bc0c38d1 | 3024 | { |
983f938a | 3025 | struct trace_array *tr = iter->tr; |
214023c3 | 3026 | struct trace_seq *s = &iter->seq; |
983f938a | 3027 | unsigned long sym_flags = (tr->trace_flags & TRACE_ITER_SYM_MASK); |
4e3c3333 | 3028 | struct trace_entry *entry; |
f633cef0 | 3029 | struct trace_event *event; |
bc0c38d1 | 3030 | |
4e3c3333 | 3031 | entry = iter->ent; |
dd0e545f | 3032 | |
a309720c SR |
3033 | test_cpu_buff_start(iter); |
3034 | ||
c4a8e8be | 3035 | event = ftrace_find_event(entry->type); |
bc0c38d1 | 3036 | |
983f938a | 3037 | if (tr->trace_flags & TRACE_ITER_CONTEXT_INFO) { |
19a7fe20 SRRH |
3038 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) |
3039 | trace_print_lat_context(iter); | |
3040 | else | |
3041 | trace_print_context(iter); | |
c4a8e8be | 3042 | } |
bc0c38d1 | 3043 | |
19a7fe20 SRRH |
3044 | if (trace_seq_has_overflowed(s)) |
3045 | return TRACE_TYPE_PARTIAL_LINE; | |
3046 | ||
268ccda0 | 3047 | if (event) |
a9a57763 | 3048 | return event->funcs->trace(iter, sym_flags, event); |
d9793bd8 | 3049 | |
19a7fe20 | 3050 | trace_seq_printf(s, "Unknown type %d\n", entry->type); |
02b67518 | 3051 | |
19a7fe20 | 3052 | return trace_handle_return(s); |
bc0c38d1 SR |
3053 | } |
3054 | ||
2c4f035f | 3055 | static enum print_line_t print_raw_fmt(struct trace_iterator *iter) |
f9896bf3 | 3056 | { |
983f938a | 3057 | struct trace_array *tr = iter->tr; |
f9896bf3 IM |
3058 | struct trace_seq *s = &iter->seq; |
3059 | struct trace_entry *entry; | |
f633cef0 | 3060 | struct trace_event *event; |
f9896bf3 IM |
3061 | |
3062 | entry = iter->ent; | |
dd0e545f | 3063 | |
983f938a | 3064 | if (tr->trace_flags & TRACE_ITER_CONTEXT_INFO) |
19a7fe20 SRRH |
3065 | trace_seq_printf(s, "%d %d %llu ", |
3066 | entry->pid, iter->cpu, iter->ts); | |
3067 | ||
3068 | if (trace_seq_has_overflowed(s)) | |
3069 | return TRACE_TYPE_PARTIAL_LINE; | |
f9896bf3 | 3070 | |
f633cef0 | 3071 | event = ftrace_find_event(entry->type); |
268ccda0 | 3072 | if (event) |
a9a57763 | 3073 | return event->funcs->raw(iter, 0, event); |
d9793bd8 | 3074 | |
19a7fe20 | 3075 | trace_seq_printf(s, "%d ?\n", entry->type); |
777e208d | 3076 | |
19a7fe20 | 3077 | return trace_handle_return(s); |
f9896bf3 IM |
3078 | } |
3079 | ||
2c4f035f | 3080 | static enum print_line_t print_hex_fmt(struct trace_iterator *iter) |
5e3ca0ec | 3081 | { |
983f938a | 3082 | struct trace_array *tr = iter->tr; |
5e3ca0ec IM |
3083 | struct trace_seq *s = &iter->seq; |
3084 | unsigned char newline = '\n'; | |
3085 | struct trace_entry *entry; | |
f633cef0 | 3086 | struct trace_event *event; |
5e3ca0ec IM |
3087 | |
3088 | entry = iter->ent; | |
dd0e545f | 3089 | |
983f938a | 3090 | if (tr->trace_flags & TRACE_ITER_CONTEXT_INFO) { |
19a7fe20 SRRH |
3091 | SEQ_PUT_HEX_FIELD(s, entry->pid); |
3092 | SEQ_PUT_HEX_FIELD(s, iter->cpu); | |
3093 | SEQ_PUT_HEX_FIELD(s, iter->ts); | |
3094 | if (trace_seq_has_overflowed(s)) | |
3095 | return TRACE_TYPE_PARTIAL_LINE; | |
c4a8e8be | 3096 | } |
5e3ca0ec | 3097 | |
f633cef0 | 3098 | event = ftrace_find_event(entry->type); |
268ccda0 | 3099 | if (event) { |
a9a57763 | 3100 | enum print_line_t ret = event->funcs->hex(iter, 0, event); |
d9793bd8 ACM |
3101 | if (ret != TRACE_TYPE_HANDLED) |
3102 | return ret; | |
3103 | } | |
7104f300 | 3104 | |
19a7fe20 | 3105 | SEQ_PUT_FIELD(s, newline); |
5e3ca0ec | 3106 | |
19a7fe20 | 3107 | return trace_handle_return(s); |
5e3ca0ec IM |
3108 | } |
3109 | ||
2c4f035f | 3110 | static enum print_line_t print_bin_fmt(struct trace_iterator *iter) |
cb0f12aa | 3111 | { |
983f938a | 3112 | struct trace_array *tr = iter->tr; |
cb0f12aa IM |
3113 | struct trace_seq *s = &iter->seq; |
3114 | struct trace_entry *entry; | |
f633cef0 | 3115 | struct trace_event *event; |
cb0f12aa IM |
3116 | |
3117 | entry = iter->ent; | |
dd0e545f | 3118 | |
983f938a | 3119 | if (tr->trace_flags & TRACE_ITER_CONTEXT_INFO) { |
19a7fe20 SRRH |
3120 | SEQ_PUT_FIELD(s, entry->pid); |
3121 | SEQ_PUT_FIELD(s, iter->cpu); | |
3122 | SEQ_PUT_FIELD(s, iter->ts); | |
3123 | if (trace_seq_has_overflowed(s)) | |
3124 | return TRACE_TYPE_PARTIAL_LINE; | |
c4a8e8be | 3125 | } |
cb0f12aa | 3126 | |
f633cef0 | 3127 | event = ftrace_find_event(entry->type); |
a9a57763 SR |
3128 | return event ? event->funcs->binary(iter, 0, event) : |
3129 | TRACE_TYPE_HANDLED; | |
cb0f12aa IM |
3130 | } |
3131 | ||
62b915f1 | 3132 | int trace_empty(struct trace_iterator *iter) |
bc0c38d1 | 3133 | { |
6d158a81 | 3134 | struct ring_buffer_iter *buf_iter; |
bc0c38d1 SR |
3135 | int cpu; |
3136 | ||
9aba60fe | 3137 | /* If we are looking at one CPU buffer, only check that one */ |
ae3b5093 | 3138 | if (iter->cpu_file != RING_BUFFER_ALL_CPUS) { |
9aba60fe | 3139 | cpu = iter->cpu_file; |
6d158a81 SR |
3140 | buf_iter = trace_buffer_iter(iter, cpu); |
3141 | if (buf_iter) { | |
3142 | if (!ring_buffer_iter_empty(buf_iter)) | |
9aba60fe SR |
3143 | return 0; |
3144 | } else { | |
12883efb | 3145 | if (!ring_buffer_empty_cpu(iter->trace_buffer->buffer, cpu)) |
9aba60fe SR |
3146 | return 0; |
3147 | } | |
3148 | return 1; | |
3149 | } | |
3150 | ||
ab46428c | 3151 | for_each_tracing_cpu(cpu) { |
6d158a81 SR |
3152 | buf_iter = trace_buffer_iter(iter, cpu); |
3153 | if (buf_iter) { | |
3154 | if (!ring_buffer_iter_empty(buf_iter)) | |
d769041f SR |
3155 | return 0; |
3156 | } else { | |
12883efb | 3157 | if (!ring_buffer_empty_cpu(iter->trace_buffer->buffer, cpu)) |
d769041f SR |
3158 | return 0; |
3159 | } | |
bc0c38d1 | 3160 | } |
d769041f | 3161 | |
797d3712 | 3162 | return 1; |
bc0c38d1 SR |
3163 | } |
3164 | ||
4f535968 | 3165 | /* Called with trace_event_read_lock() held. */ |
955b61e5 | 3166 | enum print_line_t print_trace_line(struct trace_iterator *iter) |
f9896bf3 | 3167 | { |
983f938a SRRH |
3168 | struct trace_array *tr = iter->tr; |
3169 | unsigned long trace_flags = tr->trace_flags; | |
2c4f035f FW |
3170 | enum print_line_t ret; |
3171 | ||
19a7fe20 SRRH |
3172 | if (iter->lost_events) { |
3173 | trace_seq_printf(&iter->seq, "CPU:%d [LOST %lu EVENTS]\n", | |
3174 | iter->cpu, iter->lost_events); | |
3175 | if (trace_seq_has_overflowed(&iter->seq)) | |
3176 | return TRACE_TYPE_PARTIAL_LINE; | |
3177 | } | |
bc21b478 | 3178 | |
2c4f035f FW |
3179 | if (iter->trace && iter->trace->print_line) { |
3180 | ret = iter->trace->print_line(iter); | |
3181 | if (ret != TRACE_TYPE_UNHANDLED) | |
3182 | return ret; | |
3183 | } | |
72829bc3 | 3184 | |
09ae7234 SRRH |
3185 | if (iter->ent->type == TRACE_BPUTS && |
3186 | trace_flags & TRACE_ITER_PRINTK && | |
3187 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
3188 | return trace_print_bputs_msg_only(iter); | |
3189 | ||
48ead020 FW |
3190 | if (iter->ent->type == TRACE_BPRINT && |
3191 | trace_flags & TRACE_ITER_PRINTK && | |
3192 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
5ef841f6 | 3193 | return trace_print_bprintk_msg_only(iter); |
48ead020 | 3194 | |
66896a85 FW |
3195 | if (iter->ent->type == TRACE_PRINT && |
3196 | trace_flags & TRACE_ITER_PRINTK && | |
3197 | trace_flags & TRACE_ITER_PRINTK_MSGONLY) | |
5ef841f6 | 3198 | return trace_print_printk_msg_only(iter); |
66896a85 | 3199 | |
cb0f12aa IM |
3200 | if (trace_flags & TRACE_ITER_BIN) |
3201 | return print_bin_fmt(iter); | |
3202 | ||
5e3ca0ec IM |
3203 | if (trace_flags & TRACE_ITER_HEX) |
3204 | return print_hex_fmt(iter); | |
3205 | ||
f9896bf3 IM |
3206 | if (trace_flags & TRACE_ITER_RAW) |
3207 | return print_raw_fmt(iter); | |
3208 | ||
f9896bf3 IM |
3209 | return print_trace_fmt(iter); |
3210 | } | |
3211 | ||
7e9a49ef JO |
3212 | void trace_latency_header(struct seq_file *m) |
3213 | { | |
3214 | struct trace_iterator *iter = m->private; | |
983f938a | 3215 | struct trace_array *tr = iter->tr; |
7e9a49ef JO |
3216 | |
3217 | /* print nothing if the buffers are empty */ | |
3218 | if (trace_empty(iter)) | |
3219 | return; | |
3220 | ||
3221 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) | |
3222 | print_trace_header(m, iter); | |
3223 | ||
983f938a | 3224 | if (!(tr->trace_flags & TRACE_ITER_VERBOSE)) |
7e9a49ef JO |
3225 | print_lat_help_header(m); |
3226 | } | |
3227 | ||
62b915f1 JO |
3228 | void trace_default_header(struct seq_file *m) |
3229 | { | |
3230 | struct trace_iterator *iter = m->private; | |
983f938a SRRH |
3231 | struct trace_array *tr = iter->tr; |
3232 | unsigned long trace_flags = tr->trace_flags; | |
62b915f1 | 3233 | |
f56e7f8e JO |
3234 | if (!(trace_flags & TRACE_ITER_CONTEXT_INFO)) |
3235 | return; | |
3236 | ||
62b915f1 JO |
3237 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) { |
3238 | /* print nothing if the buffers are empty */ | |
3239 | if (trace_empty(iter)) | |
3240 | return; | |
3241 | print_trace_header(m, iter); | |
3242 | if (!(trace_flags & TRACE_ITER_VERBOSE)) | |
3243 | print_lat_help_header(m); | |
3244 | } else { | |
77271ce4 SR |
3245 | if (!(trace_flags & TRACE_ITER_VERBOSE)) { |
3246 | if (trace_flags & TRACE_ITER_IRQ_INFO) | |
12883efb | 3247 | print_func_help_header_irq(iter->trace_buffer, m); |
77271ce4 | 3248 | else |
12883efb | 3249 | print_func_help_header(iter->trace_buffer, m); |
77271ce4 | 3250 | } |
62b915f1 JO |
3251 | } |
3252 | } | |
3253 | ||
e0a413f6 SR |
3254 | static void test_ftrace_alive(struct seq_file *m) |
3255 | { | |
3256 | if (!ftrace_is_dead()) | |
3257 | return; | |
d79ac28f RV |
3258 | seq_puts(m, "# WARNING: FUNCTION TRACING IS CORRUPTED\n" |
3259 | "# MAY BE MISSING FUNCTION EVENTS\n"); | |
e0a413f6 SR |
3260 | } |
3261 | ||
d8741e2e | 3262 | #ifdef CONFIG_TRACER_MAX_TRACE |
f1affcaa | 3263 | static void show_snapshot_main_help(struct seq_file *m) |
d8741e2e | 3264 | { |
d79ac28f RV |
3265 | seq_puts(m, "# echo 0 > snapshot : Clears and frees snapshot buffer\n" |
3266 | "# echo 1 > snapshot : Allocates snapshot buffer, if not already allocated.\n" | |
3267 | "# Takes a snapshot of the main buffer.\n" | |
3268 | "# echo 2 > snapshot : Clears snapshot buffer (but does not allocate or free)\n" | |
3269 | "# (Doesn't have to be '2' works with any number that\n" | |
3270 | "# is not a '0' or '1')\n"); | |
d8741e2e | 3271 | } |
f1affcaa SRRH |
3272 | |
3273 | static void show_snapshot_percpu_help(struct seq_file *m) | |
3274 | { | |
fa6f0cc7 | 3275 | seq_puts(m, "# echo 0 > snapshot : Invalid for per_cpu snapshot file.\n"); |
f1affcaa | 3276 | #ifdef CONFIG_RING_BUFFER_ALLOW_SWAP |
d79ac28f RV |
3277 | seq_puts(m, "# echo 1 > snapshot : Allocates snapshot buffer, if not already allocated.\n" |
3278 | "# Takes a snapshot of the main buffer for this cpu.\n"); | |
f1affcaa | 3279 | #else |
d79ac28f RV |
3280 | seq_puts(m, "# echo 1 > snapshot : Not supported with this kernel.\n" |
3281 | "# Must use main snapshot file to allocate.\n"); | |
f1affcaa | 3282 | #endif |
d79ac28f RV |
3283 | seq_puts(m, "# echo 2 > snapshot : Clears this cpu's snapshot buffer (but does not allocate)\n" |
3284 | "# (Doesn't have to be '2' works with any number that\n" | |
3285 | "# is not a '0' or '1')\n"); | |
f1affcaa SRRH |
3286 | } |
3287 | ||
d8741e2e SRRH |
3288 | static void print_snapshot_help(struct seq_file *m, struct trace_iterator *iter) |
3289 | { | |
45ad21ca | 3290 | if (iter->tr->allocated_snapshot) |
fa6f0cc7 | 3291 | seq_puts(m, "#\n# * Snapshot is allocated *\n#\n"); |
d8741e2e | 3292 | else |
fa6f0cc7 | 3293 | seq_puts(m, "#\n# * Snapshot is freed *\n#\n"); |
d8741e2e | 3294 | |
fa6f0cc7 | 3295 | seq_puts(m, "# Snapshot commands:\n"); |
f1affcaa SRRH |
3296 | if (iter->cpu_file == RING_BUFFER_ALL_CPUS) |
3297 | show_snapshot_main_help(m); | |
3298 | else | |
3299 | show_snapshot_percpu_help(m); | |
d8741e2e SRRH |
3300 | } |
3301 | #else | |
3302 | /* Should never be called */ | |
3303 | static inline void print_snapshot_help(struct seq_file *m, struct trace_iterator *iter) { } | |
3304 | #endif | |
3305 | ||
bc0c38d1 SR |
3306 | static int s_show(struct seq_file *m, void *v) |
3307 | { | |
3308 | struct trace_iterator *iter = v; | |
a63ce5b3 | 3309 | int ret; |
bc0c38d1 SR |
3310 | |
3311 | if (iter->ent == NULL) { | |
3312 | if (iter->tr) { | |
3313 | seq_printf(m, "# tracer: %s\n", iter->trace->name); | |
3314 | seq_puts(m, "#\n"); | |
e0a413f6 | 3315 | test_ftrace_alive(m); |
bc0c38d1 | 3316 | } |
d8741e2e SRRH |
3317 | if (iter->snapshot && trace_empty(iter)) |
3318 | print_snapshot_help(m, iter); | |
3319 | else if (iter->trace && iter->trace->print_header) | |
8bba1bf5 | 3320 | iter->trace->print_header(m); |
62b915f1 JO |
3321 | else |
3322 | trace_default_header(m); | |
3323 | ||
a63ce5b3 SR |
3324 | } else if (iter->leftover) { |
3325 | /* | |
3326 | * If we filled the seq_file buffer earlier, we | |
3327 | * want to just show it now. | |
3328 | */ | |
3329 | ret = trace_print_seq(m, &iter->seq); | |
3330 | ||
3331 | /* ret should this time be zero, but you never know */ | |
3332 | iter->leftover = ret; | |
3333 | ||
bc0c38d1 | 3334 | } else { |
f9896bf3 | 3335 | print_trace_line(iter); |
a63ce5b3 SR |
3336 | ret = trace_print_seq(m, &iter->seq); |
3337 | /* | |
3338 | * If we overflow the seq_file buffer, then it will | |
3339 | * ask us for this data again at start up. | |
3340 | * Use that instead. | |
3341 | * ret is 0 if seq_file write succeeded. | |
3342 | * -1 otherwise. | |
3343 | */ | |
3344 | iter->leftover = ret; | |
bc0c38d1 SR |
3345 | } |
3346 | ||
3347 | return 0; | |
3348 | } | |
3349 | ||
649e9c70 ON |
3350 | /* |
3351 | * Should be used after trace_array_get(), trace_types_lock | |
3352 | * ensures that i_cdev was already initialized. | |
3353 | */ | |
3354 | static inline int tracing_get_cpu(struct inode *inode) | |
3355 | { | |
3356 | if (inode->i_cdev) /* See trace_create_cpu_file() */ | |
3357 | return (long)inode->i_cdev - 1; | |
3358 | return RING_BUFFER_ALL_CPUS; | |
3359 | } | |
3360 | ||
88e9d34c | 3361 | static const struct seq_operations tracer_seq_ops = { |
4bf39a94 IM |
3362 | .start = s_start, |
3363 | .next = s_next, | |
3364 | .stop = s_stop, | |
3365 | .show = s_show, | |
bc0c38d1 SR |
3366 | }; |
3367 | ||
e309b41d | 3368 | static struct trace_iterator * |
6484c71c | 3369 | __tracing_open(struct inode *inode, struct file *file, bool snapshot) |
bc0c38d1 | 3370 | { |
6484c71c | 3371 | struct trace_array *tr = inode->i_private; |
bc0c38d1 | 3372 | struct trace_iterator *iter; |
50e18b94 | 3373 | int cpu; |
bc0c38d1 | 3374 | |
85a2f9b4 SR |
3375 | if (tracing_disabled) |
3376 | return ERR_PTR(-ENODEV); | |
60a11774 | 3377 | |
50e18b94 | 3378 | iter = __seq_open_private(file, &tracer_seq_ops, sizeof(*iter)); |
85a2f9b4 SR |
3379 | if (!iter) |
3380 | return ERR_PTR(-ENOMEM); | |
bc0c38d1 | 3381 | |
72917235 | 3382 | iter->buffer_iter = kcalloc(nr_cpu_ids, sizeof(*iter->buffer_iter), |
6d158a81 | 3383 | GFP_KERNEL); |
93574fcc DC |
3384 | if (!iter->buffer_iter) |
3385 | goto release; | |
3386 | ||
d7350c3f FW |
3387 | /* |
3388 | * We make a copy of the current tracer to avoid concurrent | |
3389 | * changes on it while we are reading. | |
3390 | */ | |
bc0c38d1 | 3391 | mutex_lock(&trace_types_lock); |
d7350c3f | 3392 | iter->trace = kzalloc(sizeof(*iter->trace), GFP_KERNEL); |
85a2f9b4 | 3393 | if (!iter->trace) |
d7350c3f | 3394 | goto fail; |
85a2f9b4 | 3395 | |
2b6080f2 | 3396 | *iter->trace = *tr->current_trace; |
d7350c3f | 3397 | |
79f55997 | 3398 | if (!zalloc_cpumask_var(&iter->started, GFP_KERNEL)) |
b0dfa978 FW |
3399 | goto fail; |
3400 | ||
12883efb SRRH |
3401 | iter->tr = tr; |
3402 | ||
3403 | #ifdef CONFIG_TRACER_MAX_TRACE | |
2b6080f2 SR |
3404 | /* Currently only the top directory has a snapshot */ |
3405 | if (tr->current_trace->print_max || snapshot) | |
12883efb | 3406 | iter->trace_buffer = &tr->max_buffer; |
bc0c38d1 | 3407 | else |
12883efb SRRH |
3408 | #endif |
3409 | iter->trace_buffer = &tr->trace_buffer; | |
debdd57f | 3410 | iter->snapshot = snapshot; |
bc0c38d1 | 3411 | iter->pos = -1; |
6484c71c | 3412 | iter->cpu_file = tracing_get_cpu(inode); |
d7350c3f | 3413 | mutex_init(&iter->mutex); |
bc0c38d1 | 3414 | |
8bba1bf5 MM |
3415 | /* Notify the tracer early; before we stop tracing. */ |
3416 | if (iter->trace && iter->trace->open) | |
a93751ca | 3417 | iter->trace->open(iter); |
8bba1bf5 | 3418 | |
12ef7d44 | 3419 | /* Annotate start of buffers if we had overruns */ |
12883efb | 3420 | if (ring_buffer_overruns(iter->trace_buffer->buffer)) |
12ef7d44 SR |
3421 | iter->iter_flags |= TRACE_FILE_ANNOTATE; |
3422 | ||
8be0709f | 3423 | /* Output in nanoseconds only if we are using a clock in nanoseconds. */ |
58e8eedf | 3424 | if (trace_clocks[tr->clock_id].in_ns) |
8be0709f DS |
3425 | iter->iter_flags |= TRACE_FILE_TIME_IN_NS; |
3426 | ||
debdd57f HT |
3427 | /* stop the trace while dumping if we are not opening "snapshot" */ |
3428 | if (!iter->snapshot) | |
2b6080f2 | 3429 | tracing_stop_tr(tr); |
2f26ebd5 | 3430 | |
ae3b5093 | 3431 | if (iter->cpu_file == RING_BUFFER_ALL_CPUS) { |
b04cc6b1 | 3432 | for_each_tracing_cpu(cpu) { |
b04cc6b1 | 3433 | iter->buffer_iter[cpu] = |
12883efb | 3434 | ring_buffer_read_prepare(iter->trace_buffer->buffer, cpu); |
72c9ddfd DM |
3435 | } |
3436 | ring_buffer_read_prepare_sync(); | |
3437 | for_each_tracing_cpu(cpu) { | |
3438 | ring_buffer_read_start(iter->buffer_iter[cpu]); | |
2f26ebd5 | 3439 | tracing_iter_reset(iter, cpu); |
b04cc6b1 FW |
3440 | } |
3441 | } else { | |
3442 | cpu = iter->cpu_file; | |
3928a8a2 | 3443 | iter->buffer_iter[cpu] = |
12883efb | 3444 | ring_buffer_read_prepare(iter->trace_buffer->buffer, cpu); |
72c9ddfd DM |
3445 | ring_buffer_read_prepare_sync(); |
3446 | ring_buffer_read_start(iter->buffer_iter[cpu]); | |
2f26ebd5 | 3447 | tracing_iter_reset(iter, cpu); |
3928a8a2 SR |
3448 | } |
3449 | ||
bc0c38d1 SR |
3450 | mutex_unlock(&trace_types_lock); |
3451 | ||
bc0c38d1 | 3452 | return iter; |
3928a8a2 | 3453 | |
d7350c3f | 3454 | fail: |
3928a8a2 | 3455 | mutex_unlock(&trace_types_lock); |
d7350c3f | 3456 | kfree(iter->trace); |
6d158a81 | 3457 | kfree(iter->buffer_iter); |
93574fcc | 3458 | release: |
50e18b94 JO |
3459 | seq_release_private(inode, file); |
3460 | return ERR_PTR(-ENOMEM); | |
bc0c38d1 SR |
3461 | } |
3462 | ||
3463 | int tracing_open_generic(struct inode *inode, struct file *filp) | |
3464 | { | |
60a11774 SR |
3465 | if (tracing_disabled) |
3466 | return -ENODEV; | |
3467 | ||
bc0c38d1 SR |
3468 | filp->private_data = inode->i_private; |
3469 | return 0; | |
3470 | } | |
3471 | ||
2e86421d GB |
3472 | bool tracing_is_disabled(void) |
3473 | { | |
3474 | return (tracing_disabled) ? true: false; | |
3475 | } | |
3476 | ||
7b85af63 SRRH |
3477 | /* |
3478 | * Open and update trace_array ref count. | |
3479 | * Must have the current trace_array passed to it. | |
3480 | */ | |
dcc30223 | 3481 | static int tracing_open_generic_tr(struct inode *inode, struct file *filp) |
7b85af63 SRRH |
3482 | { |
3483 | struct trace_array *tr = inode->i_private; | |
3484 | ||
3485 | if (tracing_disabled) | |
3486 | return -ENODEV; | |
3487 | ||
3488 | if (trace_array_get(tr) < 0) | |
3489 | return -ENODEV; | |
3490 | ||
3491 | filp->private_data = inode->i_private; | |
3492 | ||
3493 | return 0; | |
7b85af63 SRRH |
3494 | } |
3495 | ||
4fd27358 | 3496 | static int tracing_release(struct inode *inode, struct file *file) |
bc0c38d1 | 3497 | { |
6484c71c | 3498 | struct trace_array *tr = inode->i_private; |
907f2784 | 3499 | struct seq_file *m = file->private_data; |
4acd4d00 | 3500 | struct trace_iterator *iter; |
3928a8a2 | 3501 | int cpu; |
bc0c38d1 | 3502 | |
ff451961 | 3503 | if (!(file->f_mode & FMODE_READ)) { |
6484c71c | 3504 | trace_array_put(tr); |
4acd4d00 | 3505 | return 0; |
ff451961 | 3506 | } |
4acd4d00 | 3507 | |
6484c71c | 3508 | /* Writes do not use seq_file */ |
4acd4d00 | 3509 | iter = m->private; |
bc0c38d1 | 3510 | mutex_lock(&trace_types_lock); |
a695cb58 | 3511 | |
3928a8a2 SR |
3512 | for_each_tracing_cpu(cpu) { |
3513 | if (iter->buffer_iter[cpu]) | |
3514 | ring_buffer_read_finish(iter->buffer_iter[cpu]); | |
3515 | } | |
3516 | ||
bc0c38d1 SR |
3517 | if (iter->trace && iter->trace->close) |
3518 | iter->trace->close(iter); | |
3519 | ||
debdd57f HT |
3520 | if (!iter->snapshot) |
3521 | /* reenable tracing if it was previously enabled */ | |
2b6080f2 | 3522 | tracing_start_tr(tr); |
f77d09a3 AL |
3523 | |
3524 | __trace_array_put(tr); | |
3525 | ||
bc0c38d1 SR |
3526 | mutex_unlock(&trace_types_lock); |
3527 | ||
d7350c3f | 3528 | mutex_destroy(&iter->mutex); |
b0dfa978 | 3529 | free_cpumask_var(iter->started); |
d7350c3f | 3530 | kfree(iter->trace); |
6d158a81 | 3531 | kfree(iter->buffer_iter); |
50e18b94 | 3532 | seq_release_private(inode, file); |
ff451961 | 3533 | |
bc0c38d1 SR |
3534 | return 0; |
3535 | } | |
3536 | ||
7b85af63 SRRH |
3537 | static int tracing_release_generic_tr(struct inode *inode, struct file *file) |
3538 | { | |
3539 | struct trace_array *tr = inode->i_private; | |
3540 | ||
3541 | trace_array_put(tr); | |
bc0c38d1 SR |
3542 | return 0; |
3543 | } | |
3544 | ||
7b85af63 SRRH |
3545 | static int tracing_single_release_tr(struct inode *inode, struct file *file) |
3546 | { | |
3547 | struct trace_array *tr = inode->i_private; | |
3548 | ||
3549 | trace_array_put(tr); | |
3550 | ||
3551 | return single_release(inode, file); | |
3552 | } | |
3553 | ||
bc0c38d1 SR |
3554 | static int tracing_open(struct inode *inode, struct file *file) |
3555 | { | |
6484c71c | 3556 | struct trace_array *tr = inode->i_private; |
85a2f9b4 SR |
3557 | struct trace_iterator *iter; |
3558 | int ret = 0; | |
bc0c38d1 | 3559 | |
ff451961 SRRH |
3560 | if (trace_array_get(tr) < 0) |
3561 | return -ENODEV; | |
3562 | ||
4acd4d00 | 3563 | /* If this file was open for write, then erase contents */ |
6484c71c ON |
3564 | if ((file->f_mode & FMODE_WRITE) && (file->f_flags & O_TRUNC)) { |
3565 | int cpu = tracing_get_cpu(inode); | |
3566 | ||
3567 | if (cpu == RING_BUFFER_ALL_CPUS) | |
12883efb | 3568 | tracing_reset_online_cpus(&tr->trace_buffer); |
4acd4d00 | 3569 | else |
6484c71c | 3570 | tracing_reset(&tr->trace_buffer, cpu); |
4acd4d00 | 3571 | } |
bc0c38d1 | 3572 | |
4acd4d00 | 3573 | if (file->f_mode & FMODE_READ) { |
6484c71c | 3574 | iter = __tracing_open(inode, file, false); |
4acd4d00 SR |
3575 | if (IS_ERR(iter)) |
3576 | ret = PTR_ERR(iter); | |
983f938a | 3577 | else if (tr->trace_flags & TRACE_ITER_LATENCY_FMT) |
4acd4d00 SR |
3578 | iter->iter_flags |= TRACE_FILE_LAT_FMT; |
3579 | } | |
ff451961 SRRH |
3580 | |
3581 | if (ret < 0) | |
3582 | trace_array_put(tr); | |
3583 | ||
bc0c38d1 SR |
3584 | return ret; |
3585 | } | |
3586 | ||
607e2ea1 SRRH |
3587 | /* |
3588 | * Some tracers are not suitable for instance buffers. | |
3589 | * A tracer is always available for the global array (toplevel) | |
3590 | * or if it explicitly states that it is. | |
3591 | */ | |
3592 | static bool | |
3593 | trace_ok_for_array(struct tracer *t, struct trace_array *tr) | |
3594 | { | |
3595 | return (tr->flags & TRACE_ARRAY_FL_GLOBAL) || t->allow_instances; | |
3596 | } | |
3597 | ||
3598 | /* Find the next tracer that this trace array may use */ | |
3599 | static struct tracer * | |
3600 | get_tracer_for_array(struct trace_array *tr, struct tracer *t) | |
3601 | { | |
3602 | while (t && !trace_ok_for_array(t, tr)) | |
3603 | t = t->next; | |
3604 | ||
3605 | return t; | |
3606 | } | |
3607 | ||
e309b41d | 3608 | static void * |
bc0c38d1 SR |
3609 | t_next(struct seq_file *m, void *v, loff_t *pos) |
3610 | { | |
607e2ea1 | 3611 | struct trace_array *tr = m->private; |
f129e965 | 3612 | struct tracer *t = v; |
bc0c38d1 SR |
3613 | |
3614 | (*pos)++; | |
3615 | ||
3616 | if (t) | |
607e2ea1 | 3617 | t = get_tracer_for_array(tr, t->next); |
bc0c38d1 | 3618 | |
bc0c38d1 SR |
3619 | return t; |
3620 | } | |
3621 | ||
3622 | static void *t_start(struct seq_file *m, loff_t *pos) | |
3623 | { | |
607e2ea1 | 3624 | struct trace_array *tr = m->private; |
f129e965 | 3625 | struct tracer *t; |
bc0c38d1 SR |
3626 | loff_t l = 0; |
3627 | ||
3628 | mutex_lock(&trace_types_lock); | |
607e2ea1 SRRH |
3629 | |
3630 | t = get_tracer_for_array(tr, trace_types); | |
3631 | for (; t && l < *pos; t = t_next(m, t, &l)) | |
3632 | ; | |
bc0c38d1 SR |
3633 | |
3634 | return t; | |
3635 | } | |
3636 | ||
3637 | static void t_stop(struct seq_file *m, void *p) | |
3638 | { | |
3639 | mutex_unlock(&trace_types_lock); | |
3640 | } | |
3641 | ||
3642 | static int t_show(struct seq_file *m, void *v) | |
3643 | { | |
3644 | struct tracer *t = v; | |
3645 | ||
3646 | if (!t) | |
3647 | return 0; | |
3648 | ||
fa6f0cc7 | 3649 | seq_puts(m, t->name); |
bc0c38d1 SR |
3650 | if (t->next) |
3651 | seq_putc(m, ' '); | |
3652 | else | |
3653 | seq_putc(m, '\n'); | |
3654 | ||
3655 | return 0; | |
3656 | } | |
3657 | ||
88e9d34c | 3658 | static const struct seq_operations show_traces_seq_ops = { |
4bf39a94 IM |
3659 | .start = t_start, |
3660 | .next = t_next, | |
3661 | .stop = t_stop, | |
3662 | .show = t_show, | |
bc0c38d1 SR |
3663 | }; |
3664 | ||
3665 | static int show_traces_open(struct inode *inode, struct file *file) | |
3666 | { | |
607e2ea1 SRRH |
3667 | struct trace_array *tr = inode->i_private; |
3668 | struct seq_file *m; | |
3669 | int ret; | |
3670 | ||
60a11774 SR |
3671 | if (tracing_disabled) |
3672 | return -ENODEV; | |
3673 | ||
607e2ea1 SRRH |
3674 | ret = seq_open(file, &show_traces_seq_ops); |
3675 | if (ret) | |
3676 | return ret; | |
3677 | ||
3678 | m = file->private_data; | |
3679 | m->private = tr; | |
3680 | ||
3681 | return 0; | |
bc0c38d1 SR |
3682 | } |
3683 | ||
4acd4d00 SR |
3684 | static ssize_t |
3685 | tracing_write_stub(struct file *filp, const char __user *ubuf, | |
3686 | size_t count, loff_t *ppos) | |
3687 | { | |
3688 | return count; | |
3689 | } | |
3690 | ||
098c879e | 3691 | loff_t tracing_lseek(struct file *file, loff_t offset, int whence) |
364829b1 | 3692 | { |
098c879e SRRH |
3693 | int ret; |
3694 | ||
364829b1 | 3695 | if (file->f_mode & FMODE_READ) |
098c879e | 3696 | ret = seq_lseek(file, offset, whence); |
364829b1 | 3697 | else |
098c879e SRRH |
3698 | file->f_pos = ret = 0; |
3699 | ||
3700 | return ret; | |
364829b1 SP |
3701 | } |
3702 | ||
5e2336a0 | 3703 | static const struct file_operations tracing_fops = { |
4bf39a94 IM |
3704 | .open = tracing_open, |
3705 | .read = seq_read, | |
4acd4d00 | 3706 | .write = tracing_write_stub, |
098c879e | 3707 | .llseek = tracing_lseek, |
4bf39a94 | 3708 | .release = tracing_release, |
bc0c38d1 SR |
3709 | }; |
3710 | ||
5e2336a0 | 3711 | static const struct file_operations show_traces_fops = { |
c7078de1 IM |
3712 | .open = show_traces_open, |
3713 | .read = seq_read, | |
3714 | .release = seq_release, | |
b444786f | 3715 | .llseek = seq_lseek, |
c7078de1 IM |
3716 | }; |
3717 | ||
36dfe925 IM |
3718 | /* |
3719 | * The tracer itself will not take this lock, but still we want | |
3720 | * to provide a consistent cpumask to user-space: | |
3721 | */ | |
3722 | static DEFINE_MUTEX(tracing_cpumask_update_lock); | |
3723 | ||
3724 | /* | |
3725 | * Temporary storage for the character representation of the | |
3726 | * CPU bitmask (and one more byte for the newline): | |
3727 | */ | |
3728 | static char mask_str[NR_CPUS + 1]; | |
3729 | ||
c7078de1 IM |
3730 | static ssize_t |
3731 | tracing_cpumask_read(struct file *filp, char __user *ubuf, | |
3732 | size_t count, loff_t *ppos) | |
3733 | { | |
ccfe9e42 | 3734 | struct trace_array *tr = file_inode(filp)->i_private; |
36dfe925 | 3735 | int len; |
c7078de1 IM |
3736 | |
3737 | mutex_lock(&tracing_cpumask_update_lock); | |
36dfe925 | 3738 | |
1a40243b TH |
3739 | len = snprintf(mask_str, count, "%*pb\n", |
3740 | cpumask_pr_args(tr->tracing_cpumask)); | |
3741 | if (len >= count) { | |
36dfe925 IM |
3742 | count = -EINVAL; |
3743 | goto out_err; | |
3744 | } | |
36dfe925 IM |
3745 | count = simple_read_from_buffer(ubuf, count, ppos, mask_str, NR_CPUS+1); |
3746 | ||
3747 | out_err: | |
c7078de1 IM |
3748 | mutex_unlock(&tracing_cpumask_update_lock); |
3749 | ||
3750 | return count; | |
3751 | } | |
3752 | ||
3753 | static ssize_t | |
3754 | tracing_cpumask_write(struct file *filp, const char __user *ubuf, | |
3755 | size_t count, loff_t *ppos) | |
3756 | { | |
ccfe9e42 | 3757 | struct trace_array *tr = file_inode(filp)->i_private; |
9e01c1b7 | 3758 | cpumask_var_t tracing_cpumask_new; |
2b6080f2 | 3759 | int err, cpu; |
9e01c1b7 RR |
3760 | |
3761 | if (!alloc_cpumask_var(&tracing_cpumask_new, GFP_KERNEL)) | |
3762 | return -ENOMEM; | |
c7078de1 | 3763 | |
9e01c1b7 | 3764 | err = cpumask_parse_user(ubuf, count, tracing_cpumask_new); |
c7078de1 | 3765 | if (err) |
36dfe925 IM |
3766 | goto err_unlock; |
3767 | ||
215368e8 LZ |
3768 | mutex_lock(&tracing_cpumask_update_lock); |
3769 | ||
a5e25883 | 3770 | local_irq_disable(); |
0b9b12c1 | 3771 | arch_spin_lock(&tr->max_lock); |
ab46428c | 3772 | for_each_tracing_cpu(cpu) { |
36dfe925 IM |
3773 | /* |
3774 | * Increase/decrease the disabled counter if we are | |
3775 | * about to flip a bit in the cpumask: | |
3776 | */ | |
ccfe9e42 | 3777 | if (cpumask_test_cpu(cpu, tr->tracing_cpumask) && |
9e01c1b7 | 3778 | !cpumask_test_cpu(cpu, tracing_cpumask_new)) { |
12883efb SRRH |
3779 | atomic_inc(&per_cpu_ptr(tr->trace_buffer.data, cpu)->disabled); |
3780 | ring_buffer_record_disable_cpu(tr->trace_buffer.buffer, cpu); | |
36dfe925 | 3781 | } |
ccfe9e42 | 3782 | if (!cpumask_test_cpu(cpu, tr->tracing_cpumask) && |
9e01c1b7 | 3783 | cpumask_test_cpu(cpu, tracing_cpumask_new)) { |
12883efb SRRH |
3784 | atomic_dec(&per_cpu_ptr(tr->trace_buffer.data, cpu)->disabled); |
3785 | ring_buffer_record_enable_cpu(tr->trace_buffer.buffer, cpu); | |
36dfe925 IM |
3786 | } |
3787 | } | |
0b9b12c1 | 3788 | arch_spin_unlock(&tr->max_lock); |
a5e25883 | 3789 | local_irq_enable(); |
36dfe925 | 3790 | |
ccfe9e42 | 3791 | cpumask_copy(tr->tracing_cpumask, tracing_cpumask_new); |
36dfe925 IM |
3792 | |
3793 | mutex_unlock(&tracing_cpumask_update_lock); | |
9e01c1b7 | 3794 | free_cpumask_var(tracing_cpumask_new); |
c7078de1 IM |
3795 | |
3796 | return count; | |
36dfe925 IM |
3797 | |
3798 | err_unlock: | |
215368e8 | 3799 | free_cpumask_var(tracing_cpumask_new); |
36dfe925 IM |
3800 | |
3801 | return err; | |
c7078de1 IM |
3802 | } |
3803 | ||
5e2336a0 | 3804 | static const struct file_operations tracing_cpumask_fops = { |
ccfe9e42 | 3805 | .open = tracing_open_generic_tr, |
c7078de1 IM |
3806 | .read = tracing_cpumask_read, |
3807 | .write = tracing_cpumask_write, | |
ccfe9e42 | 3808 | .release = tracing_release_generic_tr, |
b444786f | 3809 | .llseek = generic_file_llseek, |
bc0c38d1 SR |
3810 | }; |
3811 | ||
fdb372ed | 3812 | static int tracing_trace_options_show(struct seq_file *m, void *v) |
bc0c38d1 | 3813 | { |
d8e83d26 | 3814 | struct tracer_opt *trace_opts; |
2b6080f2 | 3815 | struct trace_array *tr = m->private; |
d8e83d26 | 3816 | u32 tracer_flags; |
d8e83d26 | 3817 | int i; |
adf9f195 | 3818 | |
d8e83d26 | 3819 | mutex_lock(&trace_types_lock); |
2b6080f2 SR |
3820 | tracer_flags = tr->current_trace->flags->val; |
3821 | trace_opts = tr->current_trace->flags->opts; | |
d8e83d26 | 3822 | |
bc0c38d1 | 3823 | for (i = 0; trace_options[i]; i++) { |
983f938a | 3824 | if (tr->trace_flags & (1 << i)) |
fdb372ed | 3825 | seq_printf(m, "%s\n", trace_options[i]); |
bc0c38d1 | 3826 | else |
fdb372ed | 3827 | seq_printf(m, "no%s\n", trace_options[i]); |
bc0c38d1 SR |
3828 | } |
3829 | ||
adf9f195 FW |
3830 | for (i = 0; trace_opts[i].name; i++) { |
3831 | if (tracer_flags & trace_opts[i].bit) | |
fdb372ed | 3832 | seq_printf(m, "%s\n", trace_opts[i].name); |
adf9f195 | 3833 | else |
fdb372ed | 3834 | seq_printf(m, "no%s\n", trace_opts[i].name); |
adf9f195 | 3835 | } |
d8e83d26 | 3836 | mutex_unlock(&trace_types_lock); |
adf9f195 | 3837 | |
fdb372ed | 3838 | return 0; |
bc0c38d1 | 3839 | } |
bc0c38d1 | 3840 | |
8c1a49ae | 3841 | static int __set_tracer_option(struct trace_array *tr, |
8d18eaaf LZ |
3842 | struct tracer_flags *tracer_flags, |
3843 | struct tracer_opt *opts, int neg) | |
3844 | { | |
d39cdd20 | 3845 | struct tracer *trace = tracer_flags->trace; |
8d18eaaf | 3846 | int ret; |
bc0c38d1 | 3847 | |
8c1a49ae | 3848 | ret = trace->set_flag(tr, tracer_flags->val, opts->bit, !neg); |
8d18eaaf LZ |
3849 | if (ret) |
3850 | return ret; | |
3851 | ||
3852 | if (neg) | |
3853 | tracer_flags->val &= ~opts->bit; | |
3854 | else | |
3855 | tracer_flags->val |= opts->bit; | |
3856 | return 0; | |
bc0c38d1 SR |
3857 | } |
3858 | ||
adf9f195 | 3859 | /* Try to assign a tracer specific option */ |
8c1a49ae | 3860 | static int set_tracer_option(struct trace_array *tr, char *cmp, int neg) |
adf9f195 | 3861 | { |
8c1a49ae | 3862 | struct tracer *trace = tr->current_trace; |
7770841e | 3863 | struct tracer_flags *tracer_flags = trace->flags; |
adf9f195 | 3864 | struct tracer_opt *opts = NULL; |
8d18eaaf | 3865 | int i; |
adf9f195 | 3866 | |
7770841e Z |
3867 | for (i = 0; tracer_flags->opts[i].name; i++) { |
3868 | opts = &tracer_flags->opts[i]; | |
adf9f195 | 3869 | |
8d18eaaf | 3870 | if (strcmp(cmp, opts->name) == 0) |
8c1a49ae | 3871 | return __set_tracer_option(tr, trace->flags, opts, neg); |
adf9f195 | 3872 | } |
adf9f195 | 3873 | |
8d18eaaf | 3874 | return -EINVAL; |
adf9f195 FW |
3875 | } |
3876 | ||
613f04a0 SRRH |
3877 | /* Some tracers require overwrite to stay enabled */ |
3878 | int trace_keep_overwrite(struct tracer *tracer, u32 mask, int set) | |
3879 | { | |
3880 | if (tracer->enabled && (mask & TRACE_ITER_OVERWRITE) && !set) | |
3881 | return -1; | |
3882 | ||
3883 | return 0; | |
3884 | } | |
3885 | ||
2b6080f2 | 3886 | int set_tracer_flag(struct trace_array *tr, unsigned int mask, int enabled) |
af4617bd SR |
3887 | { |
3888 | /* do nothing if flag is already set */ | |
983f938a | 3889 | if (!!(tr->trace_flags & mask) == !!enabled) |
613f04a0 SRRH |
3890 | return 0; |
3891 | ||
3892 | /* Give the tracer a chance to approve the change */ | |
2b6080f2 | 3893 | if (tr->current_trace->flag_changed) |
bf6065b5 | 3894 | if (tr->current_trace->flag_changed(tr, mask, !!enabled)) |
613f04a0 | 3895 | return -EINVAL; |
af4617bd SR |
3896 | |
3897 | if (enabled) | |
983f938a | 3898 | tr->trace_flags |= mask; |
af4617bd | 3899 | else |
983f938a | 3900 | tr->trace_flags &= ~mask; |
e870e9a1 LZ |
3901 | |
3902 | if (mask == TRACE_ITER_RECORD_CMD) | |
3903 | trace_event_enable_cmd_record(enabled); | |
750912fa | 3904 | |
c37775d5 SR |
3905 | if (mask == TRACE_ITER_EVENT_FORK) |
3906 | trace_event_follow_fork(tr, enabled); | |
3907 | ||
80902822 | 3908 | if (mask == TRACE_ITER_OVERWRITE) { |
12883efb | 3909 | ring_buffer_change_overwrite(tr->trace_buffer.buffer, enabled); |
80902822 | 3910 | #ifdef CONFIG_TRACER_MAX_TRACE |
12883efb | 3911 | ring_buffer_change_overwrite(tr->max_buffer.buffer, enabled); |
80902822 SRRH |
3912 | #endif |
3913 | } | |
81698831 | 3914 | |
b9f9108c | 3915 | if (mask == TRACE_ITER_PRINTK) { |
81698831 | 3916 | trace_printk_start_stop_comm(enabled); |
b9f9108c SRRH |
3917 | trace_printk_control(enabled); |
3918 | } | |
613f04a0 SRRH |
3919 | |
3920 | return 0; | |
af4617bd SR |
3921 | } |
3922 | ||
2b6080f2 | 3923 | static int trace_set_options(struct trace_array *tr, char *option) |
bc0c38d1 | 3924 | { |
8d18eaaf | 3925 | char *cmp; |
bc0c38d1 | 3926 | int neg = 0; |
613f04a0 | 3927 | int ret = -ENODEV; |
bc0c38d1 | 3928 | int i; |
a4d1e688 | 3929 | size_t orig_len = strlen(option); |
bc0c38d1 | 3930 | |
7bcfaf54 | 3931 | cmp = strstrip(option); |
bc0c38d1 | 3932 | |
8d18eaaf | 3933 | if (strncmp(cmp, "no", 2) == 0) { |
bc0c38d1 SR |
3934 | neg = 1; |
3935 | cmp += 2; | |
3936 | } | |
3937 | ||
69d34da2 SRRH |
3938 | mutex_lock(&trace_types_lock); |
3939 | ||
bc0c38d1 | 3940 | for (i = 0; trace_options[i]; i++) { |
8d18eaaf | 3941 | if (strcmp(cmp, trace_options[i]) == 0) { |
2b6080f2 | 3942 | ret = set_tracer_flag(tr, 1 << i, !neg); |
bc0c38d1 SR |
3943 | break; |
3944 | } | |
3945 | } | |
adf9f195 FW |
3946 | |
3947 | /* If no option could be set, test the specific tracer options */ | |
69d34da2 | 3948 | if (!trace_options[i]) |
8c1a49ae | 3949 | ret = set_tracer_option(tr, cmp, neg); |
69d34da2 SRRH |
3950 | |
3951 | mutex_unlock(&trace_types_lock); | |
bc0c38d1 | 3952 | |
a4d1e688 JW |
3953 | /* |
3954 | * If the first trailing whitespace is replaced with '\0' by strstrip, | |
3955 | * turn it back into a space. | |
3956 | */ | |
3957 | if (orig_len > strlen(option)) | |
3958 | option[strlen(option)] = ' '; | |
3959 | ||
7bcfaf54 SR |
3960 | return ret; |
3961 | } | |
3962 | ||
a4d1e688 JW |
3963 | static void __init apply_trace_boot_options(void) |
3964 | { | |
3965 | char *buf = trace_boot_options_buf; | |
3966 | char *option; | |
3967 | ||
3968 | while (true) { | |
3969 | option = strsep(&buf, ","); | |
3970 | ||
3971 | if (!option) | |
3972 | break; | |
a4d1e688 | 3973 | |
43ed3843 SRRH |
3974 | if (*option) |
3975 | trace_set_options(&global_trace, option); | |
a4d1e688 JW |
3976 | |
3977 | /* Put back the comma to allow this to be called again */ | |
3978 | if (buf) | |
3979 | *(buf - 1) = ','; | |
3980 | } | |
3981 | } | |
3982 | ||
7bcfaf54 SR |
3983 | static ssize_t |
3984 | tracing_trace_options_write(struct file *filp, const char __user *ubuf, | |
3985 | size_t cnt, loff_t *ppos) | |
3986 | { | |
2b6080f2 SR |
3987 | struct seq_file *m = filp->private_data; |
3988 | struct trace_array *tr = m->private; | |
7bcfaf54 | 3989 | char buf[64]; |
613f04a0 | 3990 | int ret; |
7bcfaf54 SR |
3991 | |
3992 | if (cnt >= sizeof(buf)) | |
3993 | return -EINVAL; | |
3994 | ||
4afe6495 | 3995 | if (copy_from_user(buf, ubuf, cnt)) |
7bcfaf54 SR |
3996 | return -EFAULT; |
3997 | ||
a8dd2176 SR |
3998 | buf[cnt] = 0; |
3999 | ||
2b6080f2 | 4000 | ret = trace_set_options(tr, buf); |
613f04a0 SRRH |
4001 | if (ret < 0) |
4002 | return ret; | |
7bcfaf54 | 4003 | |
cf8517cf | 4004 | *ppos += cnt; |
bc0c38d1 SR |
4005 | |
4006 | return cnt; | |
4007 | } | |
4008 | ||
fdb372ed LZ |
4009 | static int tracing_trace_options_open(struct inode *inode, struct file *file) |
4010 | { | |
7b85af63 | 4011 | struct trace_array *tr = inode->i_private; |
f77d09a3 | 4012 | int ret; |
7b85af63 | 4013 | |
fdb372ed LZ |
4014 | if (tracing_disabled) |
4015 | return -ENODEV; | |
2b6080f2 | 4016 | |
7b85af63 SRRH |
4017 | if (trace_array_get(tr) < 0) |
4018 | return -ENODEV; | |
4019 | ||
f77d09a3 AL |
4020 | ret = single_open(file, tracing_trace_options_show, inode->i_private); |
4021 | if (ret < 0) | |
4022 | trace_array_put(tr); | |
4023 | ||
4024 | return ret; | |
fdb372ed LZ |
4025 | } |
4026 | ||
5e2336a0 | 4027 | static const struct file_operations tracing_iter_fops = { |
fdb372ed LZ |
4028 | .open = tracing_trace_options_open, |
4029 | .read = seq_read, | |
4030 | .llseek = seq_lseek, | |
7b85af63 | 4031 | .release = tracing_single_release_tr, |
ee6bce52 | 4032 | .write = tracing_trace_options_write, |
bc0c38d1 SR |
4033 | }; |
4034 | ||
7bd2f24c IM |
4035 | static const char readme_msg[] = |
4036 | "tracing mini-HOWTO:\n\n" | |
22f45649 SRRH |
4037 | "# echo 0 > tracing_on : quick way to disable tracing\n" |
4038 | "# echo 1 > tracing_on : quick way to re-enable tracing\n\n" | |
4039 | " Important files:\n" | |
4040 | " trace\t\t\t- The static contents of the buffer\n" | |
4041 | "\t\t\t To clear the buffer write into this file: echo > trace\n" | |
4042 | " trace_pipe\t\t- A consuming read to see the contents of the buffer\n" | |
4043 | " current_tracer\t- function and latency tracers\n" | |
4044 | " available_tracers\t- list of configured tracers for current_tracer\n" | |
4045 | " buffer_size_kb\t- view and modify size of per cpu buffer\n" | |
4046 | " buffer_total_size_kb - view total size of all cpu buffers\n\n" | |
4047 | " trace_clock\t\t-change the clock used to order events\n" | |
4048 | " local: Per cpu clock but may not be synced across CPUs\n" | |
4049 | " global: Synced across CPUs but slows tracing down.\n" | |
4050 | " counter: Not a clock, but just an increment\n" | |
4051 | " uptime: Jiffy counter from time of boot\n" | |
4052 | " perf: Same clock that perf events use\n" | |
4053 | #ifdef CONFIG_X86_64 | |
4054 | " x86-tsc: TSC cycle counter\n" | |
4055 | #endif | |
4056 | "\n trace_marker\t\t- Writes into this file writes into the kernel buffer\n" | |
4057 | " tracing_cpumask\t- Limit which CPUs to trace\n" | |
4058 | " instances\t\t- Make sub-buffers with: mkdir instances/foo\n" | |
4059 | "\t\t\t Remove sub-buffer with rmdir\n" | |
4060 | " trace_options\t\t- Set format or modify how tracing happens\n" | |
71485c45 SRRH |
4061 | "\t\t\t Disable an option by adding a suffix 'no' to the\n" |
4062 | "\t\t\t option name\n" | |
939c7a4f | 4063 | " saved_cmdlines_size\t- echo command number in here to store comm-pid list\n" |
22f45649 SRRH |
4064 | #ifdef CONFIG_DYNAMIC_FTRACE |
4065 | "\n available_filter_functions - list of functions that can be filtered on\n" | |
71485c45 SRRH |
4066 | " set_ftrace_filter\t- echo function name in here to only trace these\n" |
4067 | "\t\t\t functions\n" | |
4068 | "\t accepts: func_full_name, *func_end, func_begin*, *func_middle*\n" | |
4069 | "\t modules: Can select a group via module\n" | |
4070 | "\t Format: :mod:<module-name>\n" | |
4071 | "\t example: echo :mod:ext3 > set_ftrace_filter\n" | |
4072 | "\t triggers: a command to perform when function is hit\n" | |
4073 | "\t Format: <function>:<trigger>[:count]\n" | |
4074 | "\t trigger: traceon, traceoff\n" | |
4075 | "\t\t enable_event:<system>:<event>\n" | |
4076 | "\t\t disable_event:<system>:<event>\n" | |
22f45649 | 4077 | #ifdef CONFIG_STACKTRACE |
71485c45 | 4078 | "\t\t stacktrace\n" |
22f45649 SRRH |
4079 | #endif |
4080 | #ifdef CONFIG_TRACER_SNAPSHOT | |
71485c45 | 4081 | "\t\t snapshot\n" |
22f45649 | 4082 | #endif |
17a280ea SRRH |
4083 | "\t\t dump\n" |
4084 | "\t\t cpudump\n" | |
71485c45 SRRH |
4085 | "\t example: echo do_fault:traceoff > set_ftrace_filter\n" |
4086 | "\t echo do_trap:traceoff:3 > set_ftrace_filter\n" | |
4087 | "\t The first one will disable tracing every time do_fault is hit\n" | |
4088 | "\t The second will disable tracing at most 3 times when do_trap is hit\n" | |
4089 | "\t The first time do trap is hit and it disables tracing, the\n" | |
4090 | "\t counter will decrement to 2. If tracing is already disabled,\n" | |
4091 | "\t the counter will not decrement. It only decrements when the\n" | |
4092 | "\t trigger did work\n" | |
4093 | "\t To remove trigger without count:\n" | |
4094 | "\t echo '!<function>:<trigger> > set_ftrace_filter\n" | |
4095 | "\t To remove trigger with a count:\n" | |
4096 | "\t echo '!<function>:<trigger>:0 > set_ftrace_filter\n" | |
22f45649 | 4097 | " set_ftrace_notrace\t- echo function name in here to never trace.\n" |
71485c45 SRRH |
4098 | "\t accepts: func_full_name, *func_end, func_begin*, *func_middle*\n" |
4099 | "\t modules: Can select a group via module command :mod:\n" | |
4100 | "\t Does not accept triggers\n" | |
22f45649 SRRH |
4101 | #endif /* CONFIG_DYNAMIC_FTRACE */ |
4102 | #ifdef CONFIG_FUNCTION_TRACER | |
71485c45 SRRH |
4103 | " set_ftrace_pid\t- Write pid(s) to only function trace those pids\n" |
4104 | "\t\t (function)\n" | |
22f45649 SRRH |
4105 | #endif |
4106 | #ifdef CONFIG_FUNCTION_GRAPH_TRACER | |
4107 | " set_graph_function\t- Trace the nested calls of a function (function_graph)\n" | |
d048a8c7 | 4108 | " set_graph_notrace\t- Do not trace the nested calls of a function (function_graph)\n" |
22f45649 SRRH |
4109 | " max_graph_depth\t- Trace a limited depth of nested calls (0 is unlimited)\n" |
4110 | #endif | |
4111 | #ifdef CONFIG_TRACER_SNAPSHOT | |
71485c45 SRRH |
4112 | "\n snapshot\t\t- Like 'trace' but shows the content of the static\n" |
4113 | "\t\t\t snapshot buffer. Read the contents for more\n" | |
4114 | "\t\t\t information\n" | |
22f45649 | 4115 | #endif |
991821c8 | 4116 | #ifdef CONFIG_STACK_TRACER |
22f45649 SRRH |
4117 | " stack_trace\t\t- Shows the max stack trace when active\n" |
4118 | " stack_max_size\t- Shows current max stack size that was traced\n" | |
71485c45 SRRH |
4119 | "\t\t\t Write into this file to reset the max size (trigger a\n" |
4120 | "\t\t\t new trace)\n" | |
22f45649 | 4121 | #ifdef CONFIG_DYNAMIC_FTRACE |
71485c45 SRRH |
4122 | " stack_trace_filter\t- Like set_ftrace_filter but limits what stack_trace\n" |
4123 | "\t\t\t traces\n" | |
22f45649 | 4124 | #endif |
991821c8 | 4125 | #endif /* CONFIG_STACK_TRACER */ |
26f25564 TZ |
4126 | " events/\t\t- Directory containing all trace event subsystems:\n" |
4127 | " enable\t\t- Write 0/1 to enable/disable tracing of all events\n" | |
4128 | " events/<system>/\t- Directory containing all trace events for <system>:\n" | |
71485c45 SRRH |
4129 | " enable\t\t- Write 0/1 to enable/disable tracing of all <system>\n" |
4130 | "\t\t\t events\n" | |
26f25564 | 4131 | " filter\t\t- If set, only events passing filter are traced\n" |
71485c45 SRRH |
4132 | " events/<system>/<event>/\t- Directory containing control files for\n" |
4133 | "\t\t\t <event>:\n" | |
26f25564 TZ |
4134 | " enable\t\t- Write 0/1 to enable/disable tracing of <event>\n" |
4135 | " filter\t\t- If set, only events passing filter are traced\n" | |
4136 | " trigger\t\t- If set, a command to perform when event is hit\n" | |
71485c45 SRRH |
4137 | "\t Format: <trigger>[:count][if <filter>]\n" |
4138 | "\t trigger: traceon, traceoff\n" | |
4139 | "\t enable_event:<system>:<event>\n" | |
4140 | "\t disable_event:<system>:<event>\n" | |
d0bad49b TZ |
4141 | #ifdef CONFIG_HIST_TRIGGERS |
4142 | "\t enable_hist:<system>:<event>\n" | |
4143 | "\t disable_hist:<system>:<event>\n" | |
4144 | #endif | |
26f25564 | 4145 | #ifdef CONFIG_STACKTRACE |
71485c45 | 4146 | "\t\t stacktrace\n" |
26f25564 TZ |
4147 | #endif |
4148 | #ifdef CONFIG_TRACER_SNAPSHOT | |
71485c45 | 4149 | "\t\t snapshot\n" |
7ef224d1 TZ |
4150 | #endif |
4151 | #ifdef CONFIG_HIST_TRIGGERS | |
4152 | "\t\t hist (see below)\n" | |
26f25564 | 4153 | #endif |
71485c45 SRRH |
4154 | "\t example: echo traceoff > events/block/block_unplug/trigger\n" |
4155 | "\t echo traceoff:3 > events/block/block_unplug/trigger\n" | |
4156 | "\t echo 'enable_event:kmem:kmalloc:3 if nr_rq > 1' > \\\n" | |
4157 | "\t events/block/block_unplug/trigger\n" | |
4158 | "\t The first disables tracing every time block_unplug is hit.\n" | |
4159 | "\t The second disables tracing the first 3 times block_unplug is hit.\n" | |
4160 | "\t The third enables the kmalloc event the first 3 times block_unplug\n" | |
4161 | "\t is hit and has value of greater than 1 for the 'nr_rq' event field.\n" | |
4162 | "\t Like function triggers, the counter is only decremented if it\n" | |
4163 | "\t enabled or disabled tracing.\n" | |
4164 | "\t To remove a trigger without a count:\n" | |
4165 | "\t echo '!<trigger> > <system>/<event>/trigger\n" | |
4166 | "\t To remove a trigger with a count:\n" | |
4167 | "\t echo '!<trigger>:0 > <system>/<event>/trigger\n" | |
4168 | "\t Filters can be ignored when removing a trigger.\n" | |
7ef224d1 TZ |
4169 | #ifdef CONFIG_HIST_TRIGGERS |
4170 | " hist trigger\t- If set, event hits are aggregated into a hash table\n" | |
76a3b0c8 | 4171 | "\t Format: hist:keys=<field1[,field2,...]>\n" |
f2606835 | 4172 | "\t [:values=<field1[,field2,...]>]\n" |
e62347d2 | 4173 | "\t [:sort=<field1[,field2,...]>]\n" |
7ef224d1 | 4174 | "\t [:size=#entries]\n" |
e86ae9ba | 4175 | "\t [:pause][:continue][:clear]\n" |
5463bfda | 4176 | "\t [:name=histname1]\n" |
7ef224d1 TZ |
4177 | "\t [if <filter>]\n\n" |
4178 | "\t When a matching event is hit, an entry is added to a hash\n" | |
f2606835 TZ |
4179 | "\t table using the key(s) and value(s) named, and the value of a\n" |
4180 | "\t sum called 'hitcount' is incremented. Keys and values\n" | |
4181 | "\t correspond to fields in the event's format description. Keys\n" | |
69a0200c TZ |
4182 | "\t can be any field, or the special string 'stacktrace'.\n" |
4183 | "\t Compound keys consisting of up to two fields can be specified\n" | |
4184 | "\t by the 'keys' keyword. Values must correspond to numeric\n" | |
4185 | "\t fields. Sort keys consisting of up to two fields can be\n" | |
4186 | "\t specified using the 'sort' keyword. The sort direction can\n" | |
4187 | "\t be modified by appending '.descending' or '.ascending' to a\n" | |
4188 | "\t sort field. The 'size' parameter can be used to specify more\n" | |
5463bfda TZ |
4189 | "\t or fewer than the default 2048 entries for the hashtable size.\n" |
4190 | "\t If a hist trigger is given a name using the 'name' parameter,\n" | |
4191 | "\t its histogram data will be shared with other triggers of the\n" | |
4192 | "\t same name, and trigger hits will update this common data.\n\n" | |
7ef224d1 | 4193 | "\t Reading the 'hist' file for the event will dump the hash\n" |
52a7f16d TZ |
4194 | "\t table in its entirety to stdout. If there are multiple hist\n" |
4195 | "\t triggers attached to an event, there will be a table for each\n" | |
5463bfda TZ |
4196 | "\t trigger in the output. The table displayed for a named\n" |
4197 | "\t trigger will be the same as any other instance having the\n" | |
4198 | "\t same name. The default format used to display a given field\n" | |
4199 | "\t can be modified by appending any of the following modifiers\n" | |
4200 | "\t to the field name, as applicable:\n\n" | |
c6afad49 TZ |
4201 | "\t .hex display a number as a hex value\n" |
4202 | "\t .sym display an address as a symbol\n" | |
6b4827ad | 4203 | "\t .sym-offset display an address as a symbol and offset\n" |
31696198 TZ |
4204 | "\t .execname display a common_pid as a program name\n" |
4205 | "\t .syscall display a syscall id as a syscall name\n\n" | |
4b94f5b7 | 4206 | "\t .log2 display log2 value rather than raw number\n\n" |
83e99914 TZ |
4207 | "\t The 'pause' parameter can be used to pause an existing hist\n" |
4208 | "\t trigger or to start a hist trigger but not log any events\n" | |
4209 | "\t until told to do so. 'continue' can be used to start or\n" | |
4210 | "\t restart a paused hist trigger.\n\n" | |
e86ae9ba TZ |
4211 | "\t The 'clear' parameter will clear the contents of a running\n" |
4212 | "\t hist trigger and leave its current paused/active state\n" | |
4213 | "\t unchanged.\n\n" | |
d0bad49b TZ |
4214 | "\t The enable_hist and disable_hist triggers can be used to\n" |
4215 | "\t have one event conditionally start and stop another event's\n" | |
4216 | "\t already-attached hist trigger. The syntax is analagous to\n" | |
4217 | "\t the enable_event and disable_event triggers.\n" | |
7ef224d1 | 4218 | #endif |
7bd2f24c IM |
4219 | ; |
4220 | ||
4221 | static ssize_t | |
4222 | tracing_readme_read(struct file *filp, char __user *ubuf, | |
4223 | size_t cnt, loff_t *ppos) | |
4224 | { | |
4225 | return simple_read_from_buffer(ubuf, cnt, ppos, | |
4226 | readme_msg, strlen(readme_msg)); | |
4227 | } | |
4228 | ||
5e2336a0 | 4229 | static const struct file_operations tracing_readme_fops = { |
c7078de1 IM |
4230 | .open = tracing_open_generic, |
4231 | .read = tracing_readme_read, | |
b444786f | 4232 | .llseek = generic_file_llseek, |
7bd2f24c IM |
4233 | }; |
4234 | ||
42584c81 YY |
4235 | static void *saved_cmdlines_next(struct seq_file *m, void *v, loff_t *pos) |
4236 | { | |
4237 | unsigned int *ptr = v; | |
69abe6a5 | 4238 | |
42584c81 YY |
4239 | if (*pos || m->count) |
4240 | ptr++; | |
69abe6a5 | 4241 | |
42584c81 | 4242 | (*pos)++; |
69abe6a5 | 4243 | |
939c7a4f YY |
4244 | for (; ptr < &savedcmd->map_cmdline_to_pid[savedcmd->cmdline_num]; |
4245 | ptr++) { | |
42584c81 YY |
4246 | if (*ptr == -1 || *ptr == NO_CMDLINE_MAP) |
4247 | continue; | |
69abe6a5 | 4248 | |
42584c81 YY |
4249 | return ptr; |
4250 | } | |
69abe6a5 | 4251 | |
42584c81 YY |
4252 | return NULL; |
4253 | } | |
4254 | ||
4255 | static void *saved_cmdlines_start(struct seq_file *m, loff_t *pos) | |
4256 | { | |
4257 | void *v; | |
4258 | loff_t l = 0; | |
69abe6a5 | 4259 | |
4c27e756 SRRH |
4260 | preempt_disable(); |
4261 | arch_spin_lock(&trace_cmdline_lock); | |
4262 | ||
939c7a4f | 4263 | v = &savedcmd->map_cmdline_to_pid[0]; |
42584c81 YY |
4264 | while (l <= *pos) { |
4265 | v = saved_cmdlines_next(m, v, &l); | |
4266 | if (!v) | |
4267 | return NULL; | |
69abe6a5 AP |
4268 | } |
4269 | ||
42584c81 YY |
4270 | return v; |
4271 | } | |
4272 | ||
4273 | static void saved_cmdlines_stop(struct seq_file *m, void *v) | |
4274 | { | |
4c27e756 SRRH |
4275 | arch_spin_unlock(&trace_cmdline_lock); |
4276 | preempt_enable(); | |
42584c81 | 4277 | } |
69abe6a5 | 4278 | |
42584c81 YY |
4279 | static int saved_cmdlines_show(struct seq_file *m, void *v) |
4280 | { | |
4281 | char buf[TASK_COMM_LEN]; | |
4282 | unsigned int *pid = v; | |
69abe6a5 | 4283 | |
4c27e756 | 4284 | __trace_find_cmdline(*pid, buf); |
42584c81 YY |
4285 | seq_printf(m, "%d %s\n", *pid, buf); |
4286 | return 0; | |
4287 | } | |
4288 | ||
4289 | static const struct seq_operations tracing_saved_cmdlines_seq_ops = { | |
4290 | .start = saved_cmdlines_start, | |
4291 | .next = saved_cmdlines_next, | |
4292 | .stop = saved_cmdlines_stop, | |
4293 | .show = saved_cmdlines_show, | |
4294 | }; | |
4295 | ||
4296 | static int tracing_saved_cmdlines_open(struct inode *inode, struct file *filp) | |
4297 | { | |
4298 | if (tracing_disabled) | |
4299 | return -ENODEV; | |
4300 | ||
4301 | return seq_open(filp, &tracing_saved_cmdlines_seq_ops); | |
69abe6a5 AP |
4302 | } |
4303 | ||
4304 | static const struct file_operations tracing_saved_cmdlines_fops = { | |
42584c81 YY |
4305 | .open = tracing_saved_cmdlines_open, |
4306 | .read = seq_read, | |
4307 | .llseek = seq_lseek, | |
4308 | .release = seq_release, | |
69abe6a5 AP |
4309 | }; |
4310 | ||
939c7a4f YY |
4311 | static ssize_t |
4312 | tracing_saved_cmdlines_size_read(struct file *filp, char __user *ubuf, | |
4313 | size_t cnt, loff_t *ppos) | |
4314 | { | |
4315 | char buf[64]; | |
4316 | int r; | |
4317 | ||
4318 | arch_spin_lock(&trace_cmdline_lock); | |
a6af8fbf | 4319 | r = scnprintf(buf, sizeof(buf), "%u\n", savedcmd->cmdline_num); |
939c7a4f YY |
4320 | arch_spin_unlock(&trace_cmdline_lock); |
4321 | ||
4322 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
4323 | } | |
4324 | ||
4325 | static void free_saved_cmdlines_buffer(struct saved_cmdlines_buffer *s) | |
4326 | { | |
4327 | kfree(s->saved_cmdlines); | |
4328 | kfree(s->map_cmdline_to_pid); | |
4329 | kfree(s); | |
4330 | } | |
4331 | ||
4332 | static int tracing_resize_saved_cmdlines(unsigned int val) | |
4333 | { | |
4334 | struct saved_cmdlines_buffer *s, *savedcmd_temp; | |
4335 | ||
a6af8fbf | 4336 | s = kmalloc(sizeof(*s), GFP_KERNEL); |
939c7a4f YY |
4337 | if (!s) |
4338 | return -ENOMEM; | |
4339 | ||
4340 | if (allocate_cmdlines_buffer(val, s) < 0) { | |
4341 | kfree(s); | |
4342 | return -ENOMEM; | |
4343 | } | |
4344 | ||
4345 | arch_spin_lock(&trace_cmdline_lock); | |
4346 | savedcmd_temp = savedcmd; | |
4347 | savedcmd = s; | |
4348 | arch_spin_unlock(&trace_cmdline_lock); | |
4349 | free_saved_cmdlines_buffer(savedcmd_temp); | |
4350 | ||
4351 | return 0; | |
4352 | } | |
4353 | ||
4354 | static ssize_t | |
4355 | tracing_saved_cmdlines_size_write(struct file *filp, const char __user *ubuf, | |
4356 | size_t cnt, loff_t *ppos) | |
4357 | { | |
4358 | unsigned long val; | |
4359 | int ret; | |
4360 | ||
4361 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); | |
4362 | if (ret) | |
4363 | return ret; | |
4364 | ||
4365 | /* must have at least 1 entry or less than PID_MAX_DEFAULT */ | |
4366 | if (!val || val > PID_MAX_DEFAULT) | |
4367 | return -EINVAL; | |
4368 | ||
4369 | ret = tracing_resize_saved_cmdlines((unsigned int)val); | |
4370 | if (ret < 0) | |
4371 | return ret; | |
4372 | ||
4373 | *ppos += cnt; | |
4374 | ||
4375 | return cnt; | |
4376 | } | |
4377 | ||
4378 | static const struct file_operations tracing_saved_cmdlines_size_fops = { | |
4379 | .open = tracing_open_generic, | |
4380 | .read = tracing_saved_cmdlines_size_read, | |
4381 | .write = tracing_saved_cmdlines_size_write, | |
4382 | }; | |
4383 | ||
9828413d SRRH |
4384 | #ifdef CONFIG_TRACE_ENUM_MAP_FILE |
4385 | static union trace_enum_map_item * | |
4386 | update_enum_map(union trace_enum_map_item *ptr) | |
4387 | { | |
4388 | if (!ptr->map.enum_string) { | |
4389 | if (ptr->tail.next) { | |
4390 | ptr = ptr->tail.next; | |
4391 | /* Set ptr to the next real item (skip head) */ | |
4392 | ptr++; | |
4393 | } else | |
4394 | return NULL; | |
4395 | } | |
4396 | return ptr; | |
4397 | } | |
4398 | ||
4399 | static void *enum_map_next(struct seq_file *m, void *v, loff_t *pos) | |
4400 | { | |
4401 | union trace_enum_map_item *ptr = v; | |
4402 | ||
4403 | /* | |
4404 | * Paranoid! If ptr points to end, we don't want to increment past it. | |
4405 | * This really should never happen. | |
4406 | */ | |
4407 | ptr = update_enum_map(ptr); | |
4408 | if (WARN_ON_ONCE(!ptr)) | |
4409 | return NULL; | |
4410 | ||
4411 | ptr++; | |
4412 | ||
4413 | (*pos)++; | |
4414 | ||
4415 | ptr = update_enum_map(ptr); | |
4416 | ||
4417 | return ptr; | |
4418 | } | |
4419 | ||
4420 | static void *enum_map_start(struct seq_file *m, loff_t *pos) | |
4421 | { | |
4422 | union trace_enum_map_item *v; | |
4423 | loff_t l = 0; | |
4424 | ||
4425 | mutex_lock(&trace_enum_mutex); | |
4426 | ||
4427 | v = trace_enum_maps; | |
4428 | if (v) | |
4429 | v++; | |
4430 | ||
4431 | while (v && l < *pos) { | |
4432 | v = enum_map_next(m, v, &l); | |
4433 | } | |
4434 | ||
4435 | return v; | |
4436 | } | |
4437 | ||
4438 | static void enum_map_stop(struct seq_file *m, void *v) | |
4439 | { | |
4440 | mutex_unlock(&trace_enum_mutex); | |
4441 | } | |
4442 | ||
4443 | static int enum_map_show(struct seq_file *m, void *v) | |
4444 | { | |
4445 | union trace_enum_map_item *ptr = v; | |
4446 | ||
4447 | seq_printf(m, "%s %ld (%s)\n", | |
4448 | ptr->map.enum_string, ptr->map.enum_value, | |
4449 | ptr->map.system); | |
4450 | ||
4451 | return 0; | |
4452 | } | |
4453 | ||
4454 | static const struct seq_operations tracing_enum_map_seq_ops = { | |
4455 | .start = enum_map_start, | |
4456 | .next = enum_map_next, | |
4457 | .stop = enum_map_stop, | |
4458 | .show = enum_map_show, | |
4459 | }; | |
4460 | ||
4461 | static int tracing_enum_map_open(struct inode *inode, struct file *filp) | |
4462 | { | |
4463 | if (tracing_disabled) | |
4464 | return -ENODEV; | |
4465 | ||
4466 | return seq_open(filp, &tracing_enum_map_seq_ops); | |
4467 | } | |
4468 | ||
4469 | static const struct file_operations tracing_enum_map_fops = { | |
4470 | .open = tracing_enum_map_open, | |
4471 | .read = seq_read, | |
4472 | .llseek = seq_lseek, | |
4473 | .release = seq_release, | |
4474 | }; | |
4475 | ||
4476 | static inline union trace_enum_map_item * | |
4477 | trace_enum_jmp_to_tail(union trace_enum_map_item *ptr) | |
4478 | { | |
4479 | /* Return tail of array given the head */ | |
4480 | return ptr + ptr->head.length + 1; | |
4481 | } | |
4482 | ||
4483 | static void | |
4484 | trace_insert_enum_map_file(struct module *mod, struct trace_enum_map **start, | |
4485 | int len) | |
4486 | { | |
4487 | struct trace_enum_map **stop; | |
4488 | struct trace_enum_map **map; | |
4489 | union trace_enum_map_item *map_array; | |
4490 | union trace_enum_map_item *ptr; | |
4491 | ||
4492 | stop = start + len; | |
4493 | ||
4494 | /* | |
4495 | * The trace_enum_maps contains the map plus a head and tail item, | |
4496 | * where the head holds the module and length of array, and the | |
4497 | * tail holds a pointer to the next list. | |
4498 | */ | |
4499 | map_array = kmalloc(sizeof(*map_array) * (len + 2), GFP_KERNEL); | |
4500 | if (!map_array) { | |
a395d6a7 | 4501 | pr_warn("Unable to allocate trace enum mapping\n"); |
9828413d SRRH |
4502 | return; |
4503 | } | |
4504 | ||
4505 | mutex_lock(&trace_enum_mutex); | |
4506 | ||
4507 | if (!trace_enum_maps) | |
4508 | trace_enum_maps = map_array; | |
4509 | else { | |
4510 | ptr = trace_enum_maps; | |
4511 | for (;;) { | |
4512 | ptr = trace_enum_jmp_to_tail(ptr); | |
4513 | if (!ptr->tail.next) | |
4514 | break; | |
4515 | ptr = ptr->tail.next; | |
4516 | ||
4517 | } | |
4518 | ptr->tail.next = map_array; | |
4519 | } | |
4520 | map_array->head.mod = mod; | |
4521 | map_array->head.length = len; | |
4522 | map_array++; | |
4523 | ||
4524 | for (map = start; (unsigned long)map < (unsigned long)stop; map++) { | |
4525 | map_array->map = **map; | |
4526 | map_array++; | |
4527 | } | |
4528 | memset(map_array, 0, sizeof(*map_array)); | |
4529 | ||
4530 | mutex_unlock(&trace_enum_mutex); | |
4531 | } | |
4532 | ||
4533 | static void trace_create_enum_file(struct dentry *d_tracer) | |
4534 | { | |
4535 | trace_create_file("enum_map", 0444, d_tracer, | |
4536 | NULL, &tracing_enum_map_fops); | |
4537 | } | |
4538 | ||
4539 | #else /* CONFIG_TRACE_ENUM_MAP_FILE */ | |
4540 | static inline void trace_create_enum_file(struct dentry *d_tracer) { } | |
4541 | static inline void trace_insert_enum_map_file(struct module *mod, | |
4542 | struct trace_enum_map **start, int len) { } | |
4543 | #endif /* !CONFIG_TRACE_ENUM_MAP_FILE */ | |
4544 | ||
4545 | static void trace_insert_enum_map(struct module *mod, | |
4546 | struct trace_enum_map **start, int len) | |
0c564a53 SRRH |
4547 | { |
4548 | struct trace_enum_map **map; | |
0c564a53 SRRH |
4549 | |
4550 | if (len <= 0) | |
4551 | return; | |
4552 | ||
4553 | map = start; | |
4554 | ||
4555 | trace_event_enum_update(map, len); | |
9828413d SRRH |
4556 | |
4557 | trace_insert_enum_map_file(mod, start, len); | |
0c564a53 SRRH |
4558 | } |
4559 | ||
bc0c38d1 SR |
4560 | static ssize_t |
4561 | tracing_set_trace_read(struct file *filp, char __user *ubuf, | |
4562 | size_t cnt, loff_t *ppos) | |
4563 | { | |
2b6080f2 | 4564 | struct trace_array *tr = filp->private_data; |
ee6c2c1b | 4565 | char buf[MAX_TRACER_SIZE+2]; |
bc0c38d1 SR |
4566 | int r; |
4567 | ||
4568 | mutex_lock(&trace_types_lock); | |
2b6080f2 | 4569 | r = sprintf(buf, "%s\n", tr->current_trace->name); |
bc0c38d1 SR |
4570 | mutex_unlock(&trace_types_lock); |
4571 | ||
4bf39a94 | 4572 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
4573 | } |
4574 | ||
b6f11df2 ACM |
4575 | int tracer_init(struct tracer *t, struct trace_array *tr) |
4576 | { | |
12883efb | 4577 | tracing_reset_online_cpus(&tr->trace_buffer); |
b6f11df2 ACM |
4578 | return t->init(tr); |
4579 | } | |
4580 | ||
12883efb | 4581 | static void set_buffer_entries(struct trace_buffer *buf, unsigned long val) |
438ced17 VN |
4582 | { |
4583 | int cpu; | |
737223fb | 4584 | |
438ced17 | 4585 | for_each_tracing_cpu(cpu) |
12883efb | 4586 | per_cpu_ptr(buf->data, cpu)->entries = val; |
438ced17 VN |
4587 | } |
4588 | ||
12883efb | 4589 | #ifdef CONFIG_TRACER_MAX_TRACE |
d60da506 | 4590 | /* resize @tr's buffer to the size of @size_tr's entries */ |
12883efb SRRH |
4591 | static int resize_buffer_duplicate_size(struct trace_buffer *trace_buf, |
4592 | struct trace_buffer *size_buf, int cpu_id) | |
d60da506 HT |
4593 | { |
4594 | int cpu, ret = 0; | |
4595 | ||
4596 | if (cpu_id == RING_BUFFER_ALL_CPUS) { | |
4597 | for_each_tracing_cpu(cpu) { | |
12883efb SRRH |
4598 | ret = ring_buffer_resize(trace_buf->buffer, |
4599 | per_cpu_ptr(size_buf->data, cpu)->entries, cpu); | |
d60da506 HT |
4600 | if (ret < 0) |
4601 | break; | |
12883efb SRRH |
4602 | per_cpu_ptr(trace_buf->data, cpu)->entries = |
4603 | per_cpu_ptr(size_buf->data, cpu)->entries; | |
d60da506 HT |
4604 | } |
4605 | } else { | |
12883efb SRRH |
4606 | ret = ring_buffer_resize(trace_buf->buffer, |
4607 | per_cpu_ptr(size_buf->data, cpu_id)->entries, cpu_id); | |
d60da506 | 4608 | if (ret == 0) |
12883efb SRRH |
4609 | per_cpu_ptr(trace_buf->data, cpu_id)->entries = |
4610 | per_cpu_ptr(size_buf->data, cpu_id)->entries; | |
d60da506 HT |
4611 | } |
4612 | ||
4613 | return ret; | |
4614 | } | |
12883efb | 4615 | #endif /* CONFIG_TRACER_MAX_TRACE */ |
d60da506 | 4616 | |
2b6080f2 SR |
4617 | static int __tracing_resize_ring_buffer(struct trace_array *tr, |
4618 | unsigned long size, int cpu) | |
73c5162a SR |
4619 | { |
4620 | int ret; | |
4621 | ||
4622 | /* | |
4623 | * If kernel or user changes the size of the ring buffer | |
a123c52b SR |
4624 | * we use the size that was given, and we can forget about |
4625 | * expanding it later. | |
73c5162a | 4626 | */ |
55034cd6 | 4627 | ring_buffer_expanded = true; |
73c5162a | 4628 | |
b382ede6 | 4629 | /* May be called before buffers are initialized */ |
12883efb | 4630 | if (!tr->trace_buffer.buffer) |
b382ede6 SR |
4631 | return 0; |
4632 | ||
12883efb | 4633 | ret = ring_buffer_resize(tr->trace_buffer.buffer, size, cpu); |
73c5162a SR |
4634 | if (ret < 0) |
4635 | return ret; | |
4636 | ||
12883efb | 4637 | #ifdef CONFIG_TRACER_MAX_TRACE |
2b6080f2 SR |
4638 | if (!(tr->flags & TRACE_ARRAY_FL_GLOBAL) || |
4639 | !tr->current_trace->use_max_tr) | |
ef710e10 KM |
4640 | goto out; |
4641 | ||
12883efb | 4642 | ret = ring_buffer_resize(tr->max_buffer.buffer, size, cpu); |
73c5162a | 4643 | if (ret < 0) { |
12883efb SRRH |
4644 | int r = resize_buffer_duplicate_size(&tr->trace_buffer, |
4645 | &tr->trace_buffer, cpu); | |
73c5162a | 4646 | if (r < 0) { |
a123c52b SR |
4647 | /* |
4648 | * AARGH! We are left with different | |
4649 | * size max buffer!!!! | |
4650 | * The max buffer is our "snapshot" buffer. | |
4651 | * When a tracer needs a snapshot (one of the | |
4652 | * latency tracers), it swaps the max buffer | |
4653 | * with the saved snap shot. We succeeded to | |
4654 | * update the size of the main buffer, but failed to | |
4655 | * update the size of the max buffer. But when we tried | |
4656 | * to reset the main buffer to the original size, we | |
4657 | * failed there too. This is very unlikely to | |
4658 | * happen, but if it does, warn and kill all | |
4659 | * tracing. | |
4660 | */ | |
73c5162a SR |
4661 | WARN_ON(1); |
4662 | tracing_disabled = 1; | |
4663 | } | |
4664 | return ret; | |
4665 | } | |
4666 | ||
438ced17 | 4667 | if (cpu == RING_BUFFER_ALL_CPUS) |
12883efb | 4668 | set_buffer_entries(&tr->max_buffer, size); |
438ced17 | 4669 | else |
12883efb | 4670 | per_cpu_ptr(tr->max_buffer.data, cpu)->entries = size; |
438ced17 | 4671 | |
ef710e10 | 4672 | out: |
12883efb SRRH |
4673 | #endif /* CONFIG_TRACER_MAX_TRACE */ |
4674 | ||
438ced17 | 4675 | if (cpu == RING_BUFFER_ALL_CPUS) |
12883efb | 4676 | set_buffer_entries(&tr->trace_buffer, size); |
438ced17 | 4677 | else |
12883efb | 4678 | per_cpu_ptr(tr->trace_buffer.data, cpu)->entries = size; |
73c5162a SR |
4679 | |
4680 | return ret; | |
4681 | } | |
4682 | ||
2b6080f2 SR |
4683 | static ssize_t tracing_resize_ring_buffer(struct trace_array *tr, |
4684 | unsigned long size, int cpu_id) | |
4f271a2a | 4685 | { |
83f40318 | 4686 | int ret = size; |
4f271a2a VN |
4687 | |
4688 | mutex_lock(&trace_types_lock); | |
4689 | ||
438ced17 VN |
4690 | if (cpu_id != RING_BUFFER_ALL_CPUS) { |
4691 | /* make sure, this cpu is enabled in the mask */ | |
4692 | if (!cpumask_test_cpu(cpu_id, tracing_buffer_mask)) { | |
4693 | ret = -EINVAL; | |
4694 | goto out; | |
4695 | } | |
4696 | } | |
4f271a2a | 4697 | |
2b6080f2 | 4698 | ret = __tracing_resize_ring_buffer(tr, size, cpu_id); |
4f271a2a VN |
4699 | if (ret < 0) |
4700 | ret = -ENOMEM; | |
4701 | ||
438ced17 | 4702 | out: |
4f271a2a VN |
4703 | mutex_unlock(&trace_types_lock); |
4704 | ||
4705 | return ret; | |
4706 | } | |
4707 | ||
ef710e10 | 4708 | |
1852fcce SR |
4709 | /** |
4710 | * tracing_update_buffers - used by tracing facility to expand ring buffers | |
4711 | * | |
4712 | * To save on memory when the tracing is never used on a system with it | |
4713 | * configured in. The ring buffers are set to a minimum size. But once | |
4714 | * a user starts to use the tracing facility, then they need to grow | |
4715 | * to their default size. | |
4716 | * | |
4717 | * This function is to be called when a tracer is about to be used. | |
4718 | */ | |
4719 | int tracing_update_buffers(void) | |
4720 | { | |
4721 | int ret = 0; | |
4722 | ||
1027fcb2 | 4723 | mutex_lock(&trace_types_lock); |
1852fcce | 4724 | if (!ring_buffer_expanded) |
2b6080f2 | 4725 | ret = __tracing_resize_ring_buffer(&global_trace, trace_buf_size, |
438ced17 | 4726 | RING_BUFFER_ALL_CPUS); |
1027fcb2 | 4727 | mutex_unlock(&trace_types_lock); |
1852fcce SR |
4728 | |
4729 | return ret; | |
4730 | } | |
4731 | ||
577b785f SR |
4732 | struct trace_option_dentry; |
4733 | ||
37aea98b | 4734 | static void |
2b6080f2 | 4735 | create_trace_option_files(struct trace_array *tr, struct tracer *tracer); |
577b785f | 4736 | |
6b450d25 SRRH |
4737 | /* |
4738 | * Used to clear out the tracer before deletion of an instance. | |
4739 | * Must have trace_types_lock held. | |
4740 | */ | |
4741 | static void tracing_set_nop(struct trace_array *tr) | |
4742 | { | |
4743 | if (tr->current_trace == &nop_trace) | |
4744 | return; | |
4745 | ||
50512ab5 | 4746 | tr->current_trace->enabled--; |
6b450d25 SRRH |
4747 | |
4748 | if (tr->current_trace->reset) | |
4749 | tr->current_trace->reset(tr); | |
4750 | ||
4751 | tr->current_trace = &nop_trace; | |
4752 | } | |
4753 | ||
41d9c0be | 4754 | static void add_tracer_options(struct trace_array *tr, struct tracer *t) |
bc0c38d1 | 4755 | { |
09d23a1d SRRH |
4756 | /* Only enable if the directory has been created already. */ |
4757 | if (!tr->dir) | |
4758 | return; | |
4759 | ||
37aea98b | 4760 | create_trace_option_files(tr, t); |
09d23a1d SRRH |
4761 | } |
4762 | ||
4763 | static int tracing_set_tracer(struct trace_array *tr, const char *buf) | |
4764 | { | |
bc0c38d1 | 4765 | struct tracer *t; |
12883efb | 4766 | #ifdef CONFIG_TRACER_MAX_TRACE |
34600f0e | 4767 | bool had_max_tr; |
12883efb | 4768 | #endif |
d9e54076 | 4769 | int ret = 0; |
bc0c38d1 | 4770 | |
1027fcb2 SR |
4771 | mutex_lock(&trace_types_lock); |
4772 | ||
73c5162a | 4773 | if (!ring_buffer_expanded) { |
2b6080f2 | 4774 | ret = __tracing_resize_ring_buffer(tr, trace_buf_size, |
438ced17 | 4775 | RING_BUFFER_ALL_CPUS); |
73c5162a | 4776 | if (ret < 0) |
59f586db | 4777 | goto out; |
73c5162a SR |
4778 | ret = 0; |
4779 | } | |
4780 | ||
bc0c38d1 SR |
4781 | for (t = trace_types; t; t = t->next) { |
4782 | if (strcmp(t->name, buf) == 0) | |
4783 | break; | |
4784 | } | |
c2931e05 FW |
4785 | if (!t) { |
4786 | ret = -EINVAL; | |
4787 | goto out; | |
4788 | } | |
2b6080f2 | 4789 | if (t == tr->current_trace) |
bc0c38d1 SR |
4790 | goto out; |
4791 | ||
607e2ea1 SRRH |
4792 | /* Some tracers are only allowed for the top level buffer */ |
4793 | if (!trace_ok_for_array(t, tr)) { | |
4794 | ret = -EINVAL; | |
4795 | goto out; | |
4796 | } | |
4797 | ||
cf6ab6d9 SRRH |
4798 | /* If trace pipe files are being read, we can't change the tracer */ |
4799 | if (tr->current_trace->ref) { | |
4800 | ret = -EBUSY; | |
4801 | goto out; | |
4802 | } | |
4803 | ||
9f029e83 | 4804 | trace_branch_disable(); |
613f04a0 | 4805 | |
50512ab5 | 4806 | tr->current_trace->enabled--; |
613f04a0 | 4807 | |
2b6080f2 SR |
4808 | if (tr->current_trace->reset) |
4809 | tr->current_trace->reset(tr); | |
34600f0e | 4810 | |
12883efb | 4811 | /* Current trace needs to be nop_trace before synchronize_sched */ |
2b6080f2 | 4812 | tr->current_trace = &nop_trace; |
34600f0e | 4813 | |
45ad21ca SRRH |
4814 | #ifdef CONFIG_TRACER_MAX_TRACE |
4815 | had_max_tr = tr->allocated_snapshot; | |
34600f0e SR |
4816 | |
4817 | if (had_max_tr && !t->use_max_tr) { | |
4818 | /* | |
4819 | * We need to make sure that the update_max_tr sees that | |
4820 | * current_trace changed to nop_trace to keep it from | |
4821 | * swapping the buffers after we resize it. | |
4822 | * The update_max_tr is called from interrupts disabled | |
4823 | * so a synchronized_sched() is sufficient. | |
4824 | */ | |
4825 | synchronize_sched(); | |
3209cff4 | 4826 | free_snapshot(tr); |
ef710e10 | 4827 | } |
12883efb | 4828 | #endif |
12883efb SRRH |
4829 | |
4830 | #ifdef CONFIG_TRACER_MAX_TRACE | |
34600f0e | 4831 | if (t->use_max_tr && !had_max_tr) { |
3209cff4 | 4832 | ret = alloc_snapshot(tr); |
d60da506 HT |
4833 | if (ret < 0) |
4834 | goto out; | |
ef710e10 | 4835 | } |
12883efb | 4836 | #endif |
577b785f | 4837 | |
1c80025a | 4838 | if (t->init) { |
b6f11df2 | 4839 | ret = tracer_init(t, tr); |
1c80025a FW |
4840 | if (ret) |
4841 | goto out; | |
4842 | } | |
bc0c38d1 | 4843 | |
2b6080f2 | 4844 | tr->current_trace = t; |
50512ab5 | 4845 | tr->current_trace->enabled++; |
9f029e83 | 4846 | trace_branch_enable(tr); |
bc0c38d1 SR |
4847 | out: |
4848 | mutex_unlock(&trace_types_lock); | |
4849 | ||
d9e54076 PZ |
4850 | return ret; |
4851 | } | |
4852 | ||
4853 | static ssize_t | |
4854 | tracing_set_trace_write(struct file *filp, const char __user *ubuf, | |
4855 | size_t cnt, loff_t *ppos) | |
4856 | { | |
607e2ea1 | 4857 | struct trace_array *tr = filp->private_data; |
ee6c2c1b | 4858 | char buf[MAX_TRACER_SIZE+1]; |
d9e54076 PZ |
4859 | int i; |
4860 | size_t ret; | |
e6e7a65a FW |
4861 | int err; |
4862 | ||
4863 | ret = cnt; | |
d9e54076 | 4864 | |
ee6c2c1b LZ |
4865 | if (cnt > MAX_TRACER_SIZE) |
4866 | cnt = MAX_TRACER_SIZE; | |
d9e54076 | 4867 | |
4afe6495 | 4868 | if (copy_from_user(buf, ubuf, cnt)) |
d9e54076 PZ |
4869 | return -EFAULT; |
4870 | ||
4871 | buf[cnt] = 0; | |
4872 | ||
4873 | /* strip ending whitespace. */ | |
4874 | for (i = cnt - 1; i > 0 && isspace(buf[i]); i--) | |
4875 | buf[i] = 0; | |
4876 | ||
607e2ea1 | 4877 | err = tracing_set_tracer(tr, buf); |
e6e7a65a FW |
4878 | if (err) |
4879 | return err; | |
d9e54076 | 4880 | |
cf8517cf | 4881 | *ppos += ret; |
bc0c38d1 | 4882 | |
c2931e05 | 4883 | return ret; |
bc0c38d1 SR |
4884 | } |
4885 | ||
4886 | static ssize_t | |
6508fa76 SF |
4887 | tracing_nsecs_read(unsigned long *ptr, char __user *ubuf, |
4888 | size_t cnt, loff_t *ppos) | |
bc0c38d1 | 4889 | { |
bc0c38d1 SR |
4890 | char buf[64]; |
4891 | int r; | |
4892 | ||
cffae437 | 4893 | r = snprintf(buf, sizeof(buf), "%ld\n", |
bc0c38d1 | 4894 | *ptr == (unsigned long)-1 ? -1 : nsecs_to_usecs(*ptr)); |
cffae437 SR |
4895 | if (r > sizeof(buf)) |
4896 | r = sizeof(buf); | |
4bf39a94 | 4897 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
4898 | } |
4899 | ||
4900 | static ssize_t | |
6508fa76 SF |
4901 | tracing_nsecs_write(unsigned long *ptr, const char __user *ubuf, |
4902 | size_t cnt, loff_t *ppos) | |
bc0c38d1 | 4903 | { |
5e39841c | 4904 | unsigned long val; |
c6caeeb1 | 4905 | int ret; |
bc0c38d1 | 4906 | |
22fe9b54 PH |
4907 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
4908 | if (ret) | |
c6caeeb1 | 4909 | return ret; |
bc0c38d1 SR |
4910 | |
4911 | *ptr = val * 1000; | |
4912 | ||
4913 | return cnt; | |
4914 | } | |
4915 | ||
6508fa76 SF |
4916 | static ssize_t |
4917 | tracing_thresh_read(struct file *filp, char __user *ubuf, | |
4918 | size_t cnt, loff_t *ppos) | |
4919 | { | |
4920 | return tracing_nsecs_read(&tracing_thresh, ubuf, cnt, ppos); | |
4921 | } | |
4922 | ||
4923 | static ssize_t | |
4924 | tracing_thresh_write(struct file *filp, const char __user *ubuf, | |
4925 | size_t cnt, loff_t *ppos) | |
4926 | { | |
4927 | struct trace_array *tr = filp->private_data; | |
4928 | int ret; | |
4929 | ||
4930 | mutex_lock(&trace_types_lock); | |
4931 | ret = tracing_nsecs_write(&tracing_thresh, ubuf, cnt, ppos); | |
4932 | if (ret < 0) | |
4933 | goto out; | |
4934 | ||
4935 | if (tr->current_trace->update_thresh) { | |
4936 | ret = tr->current_trace->update_thresh(tr); | |
4937 | if (ret < 0) | |
4938 | goto out; | |
4939 | } | |
4940 | ||
4941 | ret = cnt; | |
4942 | out: | |
4943 | mutex_unlock(&trace_types_lock); | |
4944 | ||
4945 | return ret; | |
4946 | } | |
4947 | ||
e428abbb CG |
4948 | #ifdef CONFIG_TRACER_MAX_TRACE |
4949 | ||
6508fa76 SF |
4950 | static ssize_t |
4951 | tracing_max_lat_read(struct file *filp, char __user *ubuf, | |
4952 | size_t cnt, loff_t *ppos) | |
4953 | { | |
4954 | return tracing_nsecs_read(filp->private_data, ubuf, cnt, ppos); | |
4955 | } | |
4956 | ||
4957 | static ssize_t | |
4958 | tracing_max_lat_write(struct file *filp, const char __user *ubuf, | |
4959 | size_t cnt, loff_t *ppos) | |
4960 | { | |
4961 | return tracing_nsecs_write(filp->private_data, ubuf, cnt, ppos); | |
4962 | } | |
4963 | ||
e428abbb CG |
4964 | #endif |
4965 | ||
b3806b43 SR |
4966 | static int tracing_open_pipe(struct inode *inode, struct file *filp) |
4967 | { | |
15544209 | 4968 | struct trace_array *tr = inode->i_private; |
b3806b43 | 4969 | struct trace_iterator *iter; |
b04cc6b1 | 4970 | int ret = 0; |
b3806b43 SR |
4971 | |
4972 | if (tracing_disabled) | |
4973 | return -ENODEV; | |
4974 | ||
7b85af63 SRRH |
4975 | if (trace_array_get(tr) < 0) |
4976 | return -ENODEV; | |
4977 | ||
b04cc6b1 FW |
4978 | mutex_lock(&trace_types_lock); |
4979 | ||
b3806b43 SR |
4980 | /* create a buffer to store the information to pass to userspace */ |
4981 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); | |
b04cc6b1 FW |
4982 | if (!iter) { |
4983 | ret = -ENOMEM; | |
f77d09a3 | 4984 | __trace_array_put(tr); |
b04cc6b1 FW |
4985 | goto out; |
4986 | } | |
b3806b43 | 4987 | |
3a161d99 | 4988 | trace_seq_init(&iter->seq); |
d716ff71 | 4989 | iter->trace = tr->current_trace; |
d7350c3f | 4990 | |
4462344e | 4991 | if (!alloc_cpumask_var(&iter->started, GFP_KERNEL)) { |
b04cc6b1 | 4992 | ret = -ENOMEM; |
d7350c3f | 4993 | goto fail; |
4462344e RR |
4994 | } |
4995 | ||
a309720c | 4996 | /* trace pipe does not show start of buffer */ |
4462344e | 4997 | cpumask_setall(iter->started); |
a309720c | 4998 | |
983f938a | 4999 | if (tr->trace_flags & TRACE_ITER_LATENCY_FMT) |
112f38a7 SR |
5000 | iter->iter_flags |= TRACE_FILE_LAT_FMT; |
5001 | ||
8be0709f | 5002 | /* Output in nanoseconds only if we are using a clock in nanoseconds. */ |
58e8eedf | 5003 | if (trace_clocks[tr->clock_id].in_ns) |
8be0709f DS |
5004 | iter->iter_flags |= TRACE_FILE_TIME_IN_NS; |
5005 | ||
15544209 ON |
5006 | iter->tr = tr; |
5007 | iter->trace_buffer = &tr->trace_buffer; | |
5008 | iter->cpu_file = tracing_get_cpu(inode); | |
d7350c3f | 5009 | mutex_init(&iter->mutex); |
b3806b43 SR |
5010 | filp->private_data = iter; |
5011 | ||
107bad8b SR |
5012 | if (iter->trace->pipe_open) |
5013 | iter->trace->pipe_open(iter); | |
107bad8b | 5014 | |
b444786f | 5015 | nonseekable_open(inode, filp); |
cf6ab6d9 SRRH |
5016 | |
5017 | tr->current_trace->ref++; | |
b04cc6b1 FW |
5018 | out: |
5019 | mutex_unlock(&trace_types_lock); | |
5020 | return ret; | |
d7350c3f FW |
5021 | |
5022 | fail: | |
5023 | kfree(iter->trace); | |
5024 | kfree(iter); | |
7b85af63 | 5025 | __trace_array_put(tr); |
d7350c3f FW |
5026 | mutex_unlock(&trace_types_lock); |
5027 | return ret; | |
b3806b43 SR |
5028 | } |
5029 | ||
5030 | static int tracing_release_pipe(struct inode *inode, struct file *file) | |
5031 | { | |
5032 | struct trace_iterator *iter = file->private_data; | |
15544209 | 5033 | struct trace_array *tr = inode->i_private; |
b3806b43 | 5034 | |
b04cc6b1 FW |
5035 | mutex_lock(&trace_types_lock); |
5036 | ||
cf6ab6d9 SRRH |
5037 | tr->current_trace->ref--; |
5038 | ||
29bf4a5e | 5039 | if (iter->trace->pipe_close) |
c521efd1 SR |
5040 | iter->trace->pipe_close(iter); |
5041 | ||
b04cc6b1 FW |
5042 | mutex_unlock(&trace_types_lock); |
5043 | ||
4462344e | 5044 | free_cpumask_var(iter->started); |
d7350c3f | 5045 | mutex_destroy(&iter->mutex); |
b3806b43 | 5046 | kfree(iter); |
b3806b43 | 5047 | |
7b85af63 SRRH |
5048 | trace_array_put(tr); |
5049 | ||
b3806b43 SR |
5050 | return 0; |
5051 | } | |
5052 | ||
2a2cc8f7 | 5053 | static unsigned int |
cc60cdc9 | 5054 | trace_poll(struct trace_iterator *iter, struct file *filp, poll_table *poll_table) |
2a2cc8f7 | 5055 | { |
983f938a SRRH |
5056 | struct trace_array *tr = iter->tr; |
5057 | ||
15693458 SRRH |
5058 | /* Iterators are static, they should be filled or empty */ |
5059 | if (trace_buffer_iter(iter, iter->cpu_file)) | |
5060 | return POLLIN | POLLRDNORM; | |
2a2cc8f7 | 5061 | |
983f938a | 5062 | if (tr->trace_flags & TRACE_ITER_BLOCK) |
2a2cc8f7 SSP |
5063 | /* |
5064 | * Always select as readable when in blocking mode | |
5065 | */ | |
5066 | return POLLIN | POLLRDNORM; | |
15693458 | 5067 | else |
12883efb | 5068 | return ring_buffer_poll_wait(iter->trace_buffer->buffer, iter->cpu_file, |
15693458 | 5069 | filp, poll_table); |
2a2cc8f7 | 5070 | } |
2a2cc8f7 | 5071 | |
cc60cdc9 SR |
5072 | static unsigned int |
5073 | tracing_poll_pipe(struct file *filp, poll_table *poll_table) | |
5074 | { | |
5075 | struct trace_iterator *iter = filp->private_data; | |
5076 | ||
5077 | return trace_poll(iter, filp, poll_table); | |
2a2cc8f7 SSP |
5078 | } |
5079 | ||
d716ff71 | 5080 | /* Must be called with iter->mutex held. */ |
ff98781b | 5081 | static int tracing_wait_pipe(struct file *filp) |
b3806b43 SR |
5082 | { |
5083 | struct trace_iterator *iter = filp->private_data; | |
8b8b3683 | 5084 | int ret; |
b3806b43 | 5085 | |
b3806b43 | 5086 | while (trace_empty(iter)) { |
2dc8f095 | 5087 | |
107bad8b | 5088 | if ((filp->f_flags & O_NONBLOCK)) { |
ff98781b | 5089 | return -EAGAIN; |
107bad8b | 5090 | } |
2dc8f095 | 5091 | |
b3806b43 | 5092 | /* |
250bfd3d | 5093 | * We block until we read something and tracing is disabled. |
b3806b43 SR |
5094 | * We still block if tracing is disabled, but we have never |
5095 | * read anything. This allows a user to cat this file, and | |
5096 | * then enable tracing. But after we have read something, | |
5097 | * we give an EOF when tracing is again disabled. | |
5098 | * | |
5099 | * iter->pos will be 0 if we haven't read anything. | |
5100 | */ | |
10246fa3 | 5101 | if (!tracing_is_on() && iter->pos) |
b3806b43 | 5102 | break; |
f4874261 SRRH |
5103 | |
5104 | mutex_unlock(&iter->mutex); | |
5105 | ||
e30f53aa | 5106 | ret = wait_on_pipe(iter, false); |
f4874261 SRRH |
5107 | |
5108 | mutex_lock(&iter->mutex); | |
5109 | ||
8b8b3683 SRRH |
5110 | if (ret) |
5111 | return ret; | |
b3806b43 SR |
5112 | } |
5113 | ||
ff98781b EGM |
5114 | return 1; |
5115 | } | |
5116 | ||
5117 | /* | |
5118 | * Consumer reader. | |
5119 | */ | |
5120 | static ssize_t | |
5121 | tracing_read_pipe(struct file *filp, char __user *ubuf, | |
5122 | size_t cnt, loff_t *ppos) | |
5123 | { | |
5124 | struct trace_iterator *iter = filp->private_data; | |
5125 | ssize_t sret; | |
5126 | ||
5127 | /* return any leftover data */ | |
5128 | sret = trace_seq_to_user(&iter->seq, ubuf, cnt); | |
5129 | if (sret != -EBUSY) | |
5130 | return sret; | |
5131 | ||
f9520750 | 5132 | trace_seq_init(&iter->seq); |
ff98781b | 5133 | |
d7350c3f FW |
5134 | /* |
5135 | * Avoid more than one consumer on a single file descriptor | |
5136 | * This is just a matter of traces coherency, the ring buffer itself | |
5137 | * is protected. | |
5138 | */ | |
5139 | mutex_lock(&iter->mutex); | |
ff98781b EGM |
5140 | if (iter->trace->read) { |
5141 | sret = iter->trace->read(iter, filp, ubuf, cnt, ppos); | |
5142 | if (sret) | |
5143 | goto out; | |
5144 | } | |
5145 | ||
5146 | waitagain: | |
5147 | sret = tracing_wait_pipe(filp); | |
5148 | if (sret <= 0) | |
5149 | goto out; | |
5150 | ||
b3806b43 | 5151 | /* stop when tracing is finished */ |
ff98781b EGM |
5152 | if (trace_empty(iter)) { |
5153 | sret = 0; | |
107bad8b | 5154 | goto out; |
ff98781b | 5155 | } |
b3806b43 SR |
5156 | |
5157 | if (cnt >= PAGE_SIZE) | |
5158 | cnt = PAGE_SIZE - 1; | |
5159 | ||
53d0aa77 | 5160 | /* reset all but tr, trace, and overruns */ |
53d0aa77 SR |
5161 | memset(&iter->seq, 0, |
5162 | sizeof(struct trace_iterator) - | |
5163 | offsetof(struct trace_iterator, seq)); | |
ed5467da | 5164 | cpumask_clear(iter->started); |
4823ed7e | 5165 | iter->pos = -1; |
b3806b43 | 5166 | |
4f535968 | 5167 | trace_event_read_lock(); |
7e53bd42 | 5168 | trace_access_lock(iter->cpu_file); |
955b61e5 | 5169 | while (trace_find_next_entry_inc(iter) != NULL) { |
2c4f035f | 5170 | enum print_line_t ret; |
5ac48378 | 5171 | int save_len = iter->seq.seq.len; |
088b1e42 | 5172 | |
f9896bf3 | 5173 | ret = print_trace_line(iter); |
2c4f035f | 5174 | if (ret == TRACE_TYPE_PARTIAL_LINE) { |
088b1e42 | 5175 | /* don't print partial lines */ |
5ac48378 | 5176 | iter->seq.seq.len = save_len; |
b3806b43 | 5177 | break; |
088b1e42 | 5178 | } |
b91facc3 FW |
5179 | if (ret != TRACE_TYPE_NO_CONSUME) |
5180 | trace_consume(iter); | |
b3806b43 | 5181 | |
5ac48378 | 5182 | if (trace_seq_used(&iter->seq) >= cnt) |
b3806b43 | 5183 | break; |
ee5e51f5 JO |
5184 | |
5185 | /* | |
5186 | * Setting the full flag means we reached the trace_seq buffer | |
5187 | * size and we should leave by partial output condition above. | |
5188 | * One of the trace_seq_* functions is not used properly. | |
5189 | */ | |
5190 | WARN_ONCE(iter->seq.full, "full flag set for trace type %d", | |
5191 | iter->ent->type); | |
b3806b43 | 5192 | } |
7e53bd42 | 5193 | trace_access_unlock(iter->cpu_file); |
4f535968 | 5194 | trace_event_read_unlock(); |
b3806b43 | 5195 | |
b3806b43 | 5196 | /* Now copy what we have to the user */ |
6c6c2796 | 5197 | sret = trace_seq_to_user(&iter->seq, ubuf, cnt); |
5ac48378 | 5198 | if (iter->seq.seq.readpos >= trace_seq_used(&iter->seq)) |
f9520750 | 5199 | trace_seq_init(&iter->seq); |
9ff4b974 PP |
5200 | |
5201 | /* | |
25985edc | 5202 | * If there was nothing to send to user, in spite of consuming trace |
9ff4b974 PP |
5203 | * entries, go back to wait for more entries. |
5204 | */ | |
6c6c2796 | 5205 | if (sret == -EBUSY) |
9ff4b974 | 5206 | goto waitagain; |
b3806b43 | 5207 | |
107bad8b | 5208 | out: |
d7350c3f | 5209 | mutex_unlock(&iter->mutex); |
107bad8b | 5210 | |
6c6c2796 | 5211 | return sret; |
b3806b43 SR |
5212 | } |
5213 | ||
3c56819b EGM |
5214 | static void tracing_spd_release_pipe(struct splice_pipe_desc *spd, |
5215 | unsigned int idx) | |
5216 | { | |
5217 | __free_page(spd->pages[idx]); | |
5218 | } | |
5219 | ||
28dfef8f | 5220 | static const struct pipe_buf_operations tracing_pipe_buf_ops = { |
34cd4998 | 5221 | .can_merge = 0, |
34cd4998 | 5222 | .confirm = generic_pipe_buf_confirm, |
92fdd98c | 5223 | .release = generic_pipe_buf_release, |
34cd4998 SR |
5224 | .steal = generic_pipe_buf_steal, |
5225 | .get = generic_pipe_buf_get, | |
3c56819b EGM |
5226 | }; |
5227 | ||
34cd4998 | 5228 | static size_t |
fa7c7f6e | 5229 | tracing_fill_pipe_page(size_t rem, struct trace_iterator *iter) |
34cd4998 SR |
5230 | { |
5231 | size_t count; | |
74f06bb7 | 5232 | int save_len; |
34cd4998 SR |
5233 | int ret; |
5234 | ||
5235 | /* Seq buffer is page-sized, exactly what we need. */ | |
5236 | for (;;) { | |
74f06bb7 | 5237 | save_len = iter->seq.seq.len; |
34cd4998 | 5238 | ret = print_trace_line(iter); |
74f06bb7 SRRH |
5239 | |
5240 | if (trace_seq_has_overflowed(&iter->seq)) { | |
5241 | iter->seq.seq.len = save_len; | |
34cd4998 SR |
5242 | break; |
5243 | } | |
74f06bb7 SRRH |
5244 | |
5245 | /* | |
5246 | * This should not be hit, because it should only | |
5247 | * be set if the iter->seq overflowed. But check it | |
5248 | * anyway to be safe. | |
5249 | */ | |
34cd4998 | 5250 | if (ret == TRACE_TYPE_PARTIAL_LINE) { |
74f06bb7 SRRH |
5251 | iter->seq.seq.len = save_len; |
5252 | break; | |
5253 | } | |
5254 | ||
5ac48378 | 5255 | count = trace_seq_used(&iter->seq) - save_len; |
74f06bb7 SRRH |
5256 | if (rem < count) { |
5257 | rem = 0; | |
5258 | iter->seq.seq.len = save_len; | |
34cd4998 SR |
5259 | break; |
5260 | } | |
5261 | ||
74e7ff8c LJ |
5262 | if (ret != TRACE_TYPE_NO_CONSUME) |
5263 | trace_consume(iter); | |
34cd4998 | 5264 | rem -= count; |
955b61e5 | 5265 | if (!trace_find_next_entry_inc(iter)) { |
34cd4998 SR |
5266 | rem = 0; |
5267 | iter->ent = NULL; | |
5268 | break; | |
5269 | } | |
5270 | } | |
5271 | ||
5272 | return rem; | |
5273 | } | |
5274 | ||
3c56819b EGM |
5275 | static ssize_t tracing_splice_read_pipe(struct file *filp, |
5276 | loff_t *ppos, | |
5277 | struct pipe_inode_info *pipe, | |
5278 | size_t len, | |
5279 | unsigned int flags) | |
5280 | { | |
35f3d14d JA |
5281 | struct page *pages_def[PIPE_DEF_BUFFERS]; |
5282 | struct partial_page partial_def[PIPE_DEF_BUFFERS]; | |
3c56819b EGM |
5283 | struct trace_iterator *iter = filp->private_data; |
5284 | struct splice_pipe_desc spd = { | |
35f3d14d JA |
5285 | .pages = pages_def, |
5286 | .partial = partial_def, | |
34cd4998 | 5287 | .nr_pages = 0, /* This gets updated below. */ |
047fe360 | 5288 | .nr_pages_max = PIPE_DEF_BUFFERS, |
34cd4998 SR |
5289 | .flags = flags, |
5290 | .ops = &tracing_pipe_buf_ops, | |
5291 | .spd_release = tracing_spd_release_pipe, | |
3c56819b EGM |
5292 | }; |
5293 | ssize_t ret; | |
34cd4998 | 5294 | size_t rem; |
3c56819b EGM |
5295 | unsigned int i; |
5296 | ||
35f3d14d JA |
5297 | if (splice_grow_spd(pipe, &spd)) |
5298 | return -ENOMEM; | |
5299 | ||
d7350c3f | 5300 | mutex_lock(&iter->mutex); |
3c56819b EGM |
5301 | |
5302 | if (iter->trace->splice_read) { | |
5303 | ret = iter->trace->splice_read(iter, filp, | |
5304 | ppos, pipe, len, flags); | |
5305 | if (ret) | |
34cd4998 | 5306 | goto out_err; |
3c56819b EGM |
5307 | } |
5308 | ||
5309 | ret = tracing_wait_pipe(filp); | |
5310 | if (ret <= 0) | |
34cd4998 | 5311 | goto out_err; |
3c56819b | 5312 | |
955b61e5 | 5313 | if (!iter->ent && !trace_find_next_entry_inc(iter)) { |
3c56819b | 5314 | ret = -EFAULT; |
34cd4998 | 5315 | goto out_err; |
3c56819b EGM |
5316 | } |
5317 | ||
4f535968 | 5318 | trace_event_read_lock(); |
7e53bd42 | 5319 | trace_access_lock(iter->cpu_file); |
4f535968 | 5320 | |
3c56819b | 5321 | /* Fill as many pages as possible. */ |
a786c06d | 5322 | for (i = 0, rem = len; i < spd.nr_pages_max && rem; i++) { |
35f3d14d JA |
5323 | spd.pages[i] = alloc_page(GFP_KERNEL); |
5324 | if (!spd.pages[i]) | |
34cd4998 | 5325 | break; |
3c56819b | 5326 | |
fa7c7f6e | 5327 | rem = tracing_fill_pipe_page(rem, iter); |
3c56819b EGM |
5328 | |
5329 | /* Copy the data into the page, so we can start over. */ | |
5330 | ret = trace_seq_to_buffer(&iter->seq, | |
35f3d14d | 5331 | page_address(spd.pages[i]), |
5ac48378 | 5332 | trace_seq_used(&iter->seq)); |
3c56819b | 5333 | if (ret < 0) { |
35f3d14d | 5334 | __free_page(spd.pages[i]); |
3c56819b EGM |
5335 | break; |
5336 | } | |
35f3d14d | 5337 | spd.partial[i].offset = 0; |
5ac48378 | 5338 | spd.partial[i].len = trace_seq_used(&iter->seq); |
3c56819b | 5339 | |
f9520750 | 5340 | trace_seq_init(&iter->seq); |
3c56819b EGM |
5341 | } |
5342 | ||
7e53bd42 | 5343 | trace_access_unlock(iter->cpu_file); |
4f535968 | 5344 | trace_event_read_unlock(); |
d7350c3f | 5345 | mutex_unlock(&iter->mutex); |
3c56819b EGM |
5346 | |
5347 | spd.nr_pages = i; | |
5348 | ||
a29054d9 SRRH |
5349 | if (i) |
5350 | ret = splice_to_pipe(pipe, &spd); | |
5351 | else | |
5352 | ret = 0; | |
35f3d14d | 5353 | out: |
047fe360 | 5354 | splice_shrink_spd(&spd); |
35f3d14d | 5355 | return ret; |
3c56819b | 5356 | |
34cd4998 | 5357 | out_err: |
d7350c3f | 5358 | mutex_unlock(&iter->mutex); |
35f3d14d | 5359 | goto out; |
3c56819b EGM |
5360 | } |
5361 | ||
a98a3c3f SR |
5362 | static ssize_t |
5363 | tracing_entries_read(struct file *filp, char __user *ubuf, | |
5364 | size_t cnt, loff_t *ppos) | |
5365 | { | |
0bc392ee ON |
5366 | struct inode *inode = file_inode(filp); |
5367 | struct trace_array *tr = inode->i_private; | |
5368 | int cpu = tracing_get_cpu(inode); | |
438ced17 VN |
5369 | char buf[64]; |
5370 | int r = 0; | |
5371 | ssize_t ret; | |
a98a3c3f | 5372 | |
db526ca3 | 5373 | mutex_lock(&trace_types_lock); |
438ced17 | 5374 | |
0bc392ee | 5375 | if (cpu == RING_BUFFER_ALL_CPUS) { |
438ced17 VN |
5376 | int cpu, buf_size_same; |
5377 | unsigned long size; | |
5378 | ||
5379 | size = 0; | |
5380 | buf_size_same = 1; | |
5381 | /* check if all cpu sizes are same */ | |
5382 | for_each_tracing_cpu(cpu) { | |
5383 | /* fill in the size from first enabled cpu */ | |
5384 | if (size == 0) | |
12883efb SRRH |
5385 | size = per_cpu_ptr(tr->trace_buffer.data, cpu)->entries; |
5386 | if (size != per_cpu_ptr(tr->trace_buffer.data, cpu)->entries) { | |
438ced17 VN |
5387 | buf_size_same = 0; |
5388 | break; | |
5389 | } | |
5390 | } | |
5391 | ||
5392 | if (buf_size_same) { | |
5393 | if (!ring_buffer_expanded) | |
5394 | r = sprintf(buf, "%lu (expanded: %lu)\n", | |
5395 | size >> 10, | |
5396 | trace_buf_size >> 10); | |
5397 | else | |
5398 | r = sprintf(buf, "%lu\n", size >> 10); | |
5399 | } else | |
5400 | r = sprintf(buf, "X\n"); | |
5401 | } else | |
0bc392ee | 5402 | r = sprintf(buf, "%lu\n", per_cpu_ptr(tr->trace_buffer.data, cpu)->entries >> 10); |
438ced17 | 5403 | |
db526ca3 SR |
5404 | mutex_unlock(&trace_types_lock); |
5405 | ||
438ced17 VN |
5406 | ret = simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
5407 | return ret; | |
a98a3c3f SR |
5408 | } |
5409 | ||
5410 | static ssize_t | |
5411 | tracing_entries_write(struct file *filp, const char __user *ubuf, | |
5412 | size_t cnt, loff_t *ppos) | |
5413 | { | |
0bc392ee ON |
5414 | struct inode *inode = file_inode(filp); |
5415 | struct trace_array *tr = inode->i_private; | |
a98a3c3f | 5416 | unsigned long val; |
4f271a2a | 5417 | int ret; |
a98a3c3f | 5418 | |
22fe9b54 PH |
5419 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
5420 | if (ret) | |
c6caeeb1 | 5421 | return ret; |
a98a3c3f SR |
5422 | |
5423 | /* must have at least 1 entry */ | |
5424 | if (!val) | |
5425 | return -EINVAL; | |
5426 | ||
1696b2b0 SR |
5427 | /* value is in KB */ |
5428 | val <<= 10; | |
0bc392ee | 5429 | ret = tracing_resize_ring_buffer(tr, val, tracing_get_cpu(inode)); |
4f271a2a VN |
5430 | if (ret < 0) |
5431 | return ret; | |
a98a3c3f | 5432 | |
cf8517cf | 5433 | *ppos += cnt; |
a98a3c3f | 5434 | |
4f271a2a VN |
5435 | return cnt; |
5436 | } | |
bf5e6519 | 5437 | |
f81ab074 VN |
5438 | static ssize_t |
5439 | tracing_total_entries_read(struct file *filp, char __user *ubuf, | |
5440 | size_t cnt, loff_t *ppos) | |
5441 | { | |
5442 | struct trace_array *tr = filp->private_data; | |
5443 | char buf[64]; | |
5444 | int r, cpu; | |
5445 | unsigned long size = 0, expanded_size = 0; | |
5446 | ||
5447 | mutex_lock(&trace_types_lock); | |
5448 | for_each_tracing_cpu(cpu) { | |
12883efb | 5449 | size += per_cpu_ptr(tr->trace_buffer.data, cpu)->entries >> 10; |
f81ab074 VN |
5450 | if (!ring_buffer_expanded) |
5451 | expanded_size += trace_buf_size >> 10; | |
5452 | } | |
5453 | if (ring_buffer_expanded) | |
5454 | r = sprintf(buf, "%lu\n", size); | |
5455 | else | |
5456 | r = sprintf(buf, "%lu (expanded: %lu)\n", size, expanded_size); | |
5457 | mutex_unlock(&trace_types_lock); | |
5458 | ||
5459 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
5460 | } | |
5461 | ||
4f271a2a VN |
5462 | static ssize_t |
5463 | tracing_free_buffer_write(struct file *filp, const char __user *ubuf, | |
5464 | size_t cnt, loff_t *ppos) | |
5465 | { | |
5466 | /* | |
5467 | * There is no need to read what the user has written, this function | |
5468 | * is just to make sure that there is no error when "echo" is used | |
5469 | */ | |
5470 | ||
5471 | *ppos += cnt; | |
a98a3c3f SR |
5472 | |
5473 | return cnt; | |
5474 | } | |
5475 | ||
4f271a2a VN |
5476 | static int |
5477 | tracing_free_buffer_release(struct inode *inode, struct file *filp) | |
5478 | { | |
2b6080f2 SR |
5479 | struct trace_array *tr = inode->i_private; |
5480 | ||
cf30cf67 | 5481 | /* disable tracing ? */ |
983f938a | 5482 | if (tr->trace_flags & TRACE_ITER_STOP_ON_FREE) |
711e1243 | 5483 | tracer_tracing_off(tr); |
4f271a2a | 5484 | /* resize the ring buffer to 0 */ |
2b6080f2 | 5485 | tracing_resize_ring_buffer(tr, 0, RING_BUFFER_ALL_CPUS); |
4f271a2a | 5486 | |
7b85af63 SRRH |
5487 | trace_array_put(tr); |
5488 | ||
4f271a2a VN |
5489 | return 0; |
5490 | } | |
5491 | ||
5bf9a1ee PP |
5492 | static ssize_t |
5493 | tracing_mark_write(struct file *filp, const char __user *ubuf, | |
5494 | size_t cnt, loff_t *fpos) | |
5495 | { | |
d696b58c | 5496 | unsigned long addr = (unsigned long)ubuf; |
2d71619c | 5497 | struct trace_array *tr = filp->private_data; |
d696b58c SR |
5498 | struct ring_buffer_event *event; |
5499 | struct ring_buffer *buffer; | |
5500 | struct print_entry *entry; | |
5501 | unsigned long irq_flags; | |
5502 | struct page *pages[2]; | |
6edb2a8a | 5503 | void *map_page[2]; |
d696b58c SR |
5504 | int nr_pages = 1; |
5505 | ssize_t written; | |
d696b58c SR |
5506 | int offset; |
5507 | int size; | |
5508 | int len; | |
5509 | int ret; | |
6edb2a8a | 5510 | int i; |
5bf9a1ee | 5511 | |
c76f0694 | 5512 | if (tracing_disabled) |
5bf9a1ee PP |
5513 | return -EINVAL; |
5514 | ||
983f938a | 5515 | if (!(tr->trace_flags & TRACE_ITER_MARKERS)) |
5224c3a3 MSB |
5516 | return -EINVAL; |
5517 | ||
5bf9a1ee PP |
5518 | if (cnt > TRACE_BUF_SIZE) |
5519 | cnt = TRACE_BUF_SIZE; | |
5520 | ||
d696b58c SR |
5521 | /* |
5522 | * Userspace is injecting traces into the kernel trace buffer. | |
5523 | * We want to be as non intrusive as possible. | |
5524 | * To do so, we do not want to allocate any special buffers | |
5525 | * or take any locks, but instead write the userspace data | |
5526 | * straight into the ring buffer. | |
5527 | * | |
5528 | * First we need to pin the userspace buffer into memory, | |
5529 | * which, most likely it is, because it just referenced it. | |
5530 | * But there's no guarantee that it is. By using get_user_pages_fast() | |
5531 | * and kmap_atomic/kunmap_atomic() we can get access to the | |
5532 | * pages directly. We then write the data directly into the | |
5533 | * ring buffer. | |
5534 | */ | |
5535 | BUILD_BUG_ON(TRACE_BUF_SIZE >= PAGE_SIZE); | |
5bf9a1ee | 5536 | |
d696b58c SR |
5537 | /* check if we cross pages */ |
5538 | if ((addr & PAGE_MASK) != ((addr + cnt) & PAGE_MASK)) | |
5539 | nr_pages = 2; | |
5540 | ||
5541 | offset = addr & (PAGE_SIZE - 1); | |
5542 | addr &= PAGE_MASK; | |
5543 | ||
5544 | ret = get_user_pages_fast(addr, nr_pages, 0, pages); | |
5545 | if (ret < nr_pages) { | |
5546 | while (--ret >= 0) | |
5547 | put_page(pages[ret]); | |
5548 | written = -EFAULT; | |
5549 | goto out; | |
5bf9a1ee | 5550 | } |
d696b58c | 5551 | |
6edb2a8a SR |
5552 | for (i = 0; i < nr_pages; i++) |
5553 | map_page[i] = kmap_atomic(pages[i]); | |
d696b58c SR |
5554 | |
5555 | local_save_flags(irq_flags); | |
5556 | size = sizeof(*entry) + cnt + 2; /* possible \n added */ | |
2d71619c | 5557 | buffer = tr->trace_buffer.buffer; |
d696b58c SR |
5558 | event = trace_buffer_lock_reserve(buffer, TRACE_PRINT, size, |
5559 | irq_flags, preempt_count()); | |
5560 | if (!event) { | |
5561 | /* Ring buffer disabled, return as if not open for write */ | |
5562 | written = -EBADF; | |
5563 | goto out_unlock; | |
5bf9a1ee | 5564 | } |
d696b58c SR |
5565 | |
5566 | entry = ring_buffer_event_data(event); | |
5567 | entry->ip = _THIS_IP_; | |
5568 | ||
5569 | if (nr_pages == 2) { | |
5570 | len = PAGE_SIZE - offset; | |
6edb2a8a SR |
5571 | memcpy(&entry->buf, map_page[0] + offset, len); |
5572 | memcpy(&entry->buf[len], map_page[1], cnt - len); | |
c13d2f7c | 5573 | } else |
6edb2a8a | 5574 | memcpy(&entry->buf, map_page[0] + offset, cnt); |
5bf9a1ee | 5575 | |
d696b58c SR |
5576 | if (entry->buf[cnt - 1] != '\n') { |
5577 | entry->buf[cnt] = '\n'; | |
5578 | entry->buf[cnt + 1] = '\0'; | |
5579 | } else | |
5580 | entry->buf[cnt] = '\0'; | |
5581 | ||
7ffbd48d | 5582 | __buffer_unlock_commit(buffer, event); |
5bf9a1ee | 5583 | |
d696b58c | 5584 | written = cnt; |
5bf9a1ee | 5585 | |
d696b58c | 5586 | *fpos += written; |
1aa54bca | 5587 | |
d696b58c | 5588 | out_unlock: |
7215853e | 5589 | for (i = nr_pages - 1; i >= 0; i--) { |
6edb2a8a SR |
5590 | kunmap_atomic(map_page[i]); |
5591 | put_page(pages[i]); | |
5592 | } | |
d696b58c | 5593 | out: |
1aa54bca | 5594 | return written; |
5bf9a1ee PP |
5595 | } |
5596 | ||
13f16d20 | 5597 | static int tracing_clock_show(struct seq_file *m, void *v) |
5079f326 | 5598 | { |
2b6080f2 | 5599 | struct trace_array *tr = m->private; |
5079f326 Z |
5600 | int i; |
5601 | ||
5602 | for (i = 0; i < ARRAY_SIZE(trace_clocks); i++) | |
13f16d20 | 5603 | seq_printf(m, |
5079f326 | 5604 | "%s%s%s%s", i ? " " : "", |
2b6080f2 SR |
5605 | i == tr->clock_id ? "[" : "", trace_clocks[i].name, |
5606 | i == tr->clock_id ? "]" : ""); | |
13f16d20 | 5607 | seq_putc(m, '\n'); |
5079f326 | 5608 | |
13f16d20 | 5609 | return 0; |
5079f326 Z |
5610 | } |
5611 | ||
e1e232ca | 5612 | static int tracing_set_clock(struct trace_array *tr, const char *clockstr) |
5079f326 | 5613 | { |
5079f326 Z |
5614 | int i; |
5615 | ||
5079f326 Z |
5616 | for (i = 0; i < ARRAY_SIZE(trace_clocks); i++) { |
5617 | if (strcmp(trace_clocks[i].name, clockstr) == 0) | |
5618 | break; | |
5619 | } | |
5620 | if (i == ARRAY_SIZE(trace_clocks)) | |
5621 | return -EINVAL; | |
5622 | ||
5079f326 Z |
5623 | mutex_lock(&trace_types_lock); |
5624 | ||
2b6080f2 SR |
5625 | tr->clock_id = i; |
5626 | ||
12883efb | 5627 | ring_buffer_set_clock(tr->trace_buffer.buffer, trace_clocks[i].func); |
5079f326 | 5628 | |
60303ed3 DS |
5629 | /* |
5630 | * New clock may not be consistent with the previous clock. | |
5631 | * Reset the buffer so that it doesn't have incomparable timestamps. | |
5632 | */ | |
9457158b | 5633 | tracing_reset_online_cpus(&tr->trace_buffer); |
12883efb SRRH |
5634 | |
5635 | #ifdef CONFIG_TRACER_MAX_TRACE | |
5636 | if (tr->flags & TRACE_ARRAY_FL_GLOBAL && tr->max_buffer.buffer) | |
5637 | ring_buffer_set_clock(tr->max_buffer.buffer, trace_clocks[i].func); | |
9457158b | 5638 | tracing_reset_online_cpus(&tr->max_buffer); |
12883efb | 5639 | #endif |
60303ed3 | 5640 | |
5079f326 Z |
5641 | mutex_unlock(&trace_types_lock); |
5642 | ||
e1e232ca SR |
5643 | return 0; |
5644 | } | |
5645 | ||
5646 | static ssize_t tracing_clock_write(struct file *filp, const char __user *ubuf, | |
5647 | size_t cnt, loff_t *fpos) | |
5648 | { | |
5649 | struct seq_file *m = filp->private_data; | |
5650 | struct trace_array *tr = m->private; | |
5651 | char buf[64]; | |
5652 | const char *clockstr; | |
5653 | int ret; | |
5654 | ||
5655 | if (cnt >= sizeof(buf)) | |
5656 | return -EINVAL; | |
5657 | ||
4afe6495 | 5658 | if (copy_from_user(buf, ubuf, cnt)) |
e1e232ca SR |
5659 | return -EFAULT; |
5660 | ||
5661 | buf[cnt] = 0; | |
5662 | ||
5663 | clockstr = strstrip(buf); | |
5664 | ||
5665 | ret = tracing_set_clock(tr, clockstr); | |
5666 | if (ret) | |
5667 | return ret; | |
5668 | ||
5079f326 Z |
5669 | *fpos += cnt; |
5670 | ||
5671 | return cnt; | |
5672 | } | |
5673 | ||
13f16d20 LZ |
5674 | static int tracing_clock_open(struct inode *inode, struct file *file) |
5675 | { | |
7b85af63 SRRH |
5676 | struct trace_array *tr = inode->i_private; |
5677 | int ret; | |
5678 | ||
13f16d20 LZ |
5679 | if (tracing_disabled) |
5680 | return -ENODEV; | |
2b6080f2 | 5681 | |
7b85af63 SRRH |
5682 | if (trace_array_get(tr)) |
5683 | return -ENODEV; | |
5684 | ||
5685 | ret = single_open(file, tracing_clock_show, inode->i_private); | |
5686 | if (ret < 0) | |
5687 | trace_array_put(tr); | |
5688 | ||
5689 | return ret; | |
13f16d20 LZ |
5690 | } |
5691 | ||
6de58e62 SRRH |
5692 | struct ftrace_buffer_info { |
5693 | struct trace_iterator iter; | |
5694 | void *spare; | |
5695 | unsigned int read; | |
5696 | }; | |
5697 | ||
debdd57f HT |
5698 | #ifdef CONFIG_TRACER_SNAPSHOT |
5699 | static int tracing_snapshot_open(struct inode *inode, struct file *file) | |
5700 | { | |
6484c71c | 5701 | struct trace_array *tr = inode->i_private; |
debdd57f | 5702 | struct trace_iterator *iter; |
2b6080f2 | 5703 | struct seq_file *m; |
debdd57f HT |
5704 | int ret = 0; |
5705 | ||
ff451961 SRRH |
5706 | if (trace_array_get(tr) < 0) |
5707 | return -ENODEV; | |
5708 | ||
debdd57f | 5709 | if (file->f_mode & FMODE_READ) { |
6484c71c | 5710 | iter = __tracing_open(inode, file, true); |
debdd57f HT |
5711 | if (IS_ERR(iter)) |
5712 | ret = PTR_ERR(iter); | |
2b6080f2 SR |
5713 | } else { |
5714 | /* Writes still need the seq_file to hold the private data */ | |
f77d09a3 | 5715 | ret = -ENOMEM; |
2b6080f2 SR |
5716 | m = kzalloc(sizeof(*m), GFP_KERNEL); |
5717 | if (!m) | |
f77d09a3 | 5718 | goto out; |
2b6080f2 SR |
5719 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); |
5720 | if (!iter) { | |
5721 | kfree(m); | |
f77d09a3 | 5722 | goto out; |
2b6080f2 | 5723 | } |
f77d09a3 AL |
5724 | ret = 0; |
5725 | ||
ff451961 | 5726 | iter->tr = tr; |
6484c71c ON |
5727 | iter->trace_buffer = &tr->max_buffer; |
5728 | iter->cpu_file = tracing_get_cpu(inode); | |
2b6080f2 SR |
5729 | m->private = iter; |
5730 | file->private_data = m; | |
debdd57f | 5731 | } |
f77d09a3 | 5732 | out: |
ff451961 SRRH |
5733 | if (ret < 0) |
5734 | trace_array_put(tr); | |
5735 | ||
debdd57f HT |
5736 | return ret; |
5737 | } | |
5738 | ||
5739 | static ssize_t | |
5740 | tracing_snapshot_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
5741 | loff_t *ppos) | |
5742 | { | |
2b6080f2 SR |
5743 | struct seq_file *m = filp->private_data; |
5744 | struct trace_iterator *iter = m->private; | |
5745 | struct trace_array *tr = iter->tr; | |
debdd57f HT |
5746 | unsigned long val; |
5747 | int ret; | |
5748 | ||
5749 | ret = tracing_update_buffers(); | |
5750 | if (ret < 0) | |
5751 | return ret; | |
5752 | ||
5753 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); | |
5754 | if (ret) | |
5755 | return ret; | |
5756 | ||
5757 | mutex_lock(&trace_types_lock); | |
5758 | ||
2b6080f2 | 5759 | if (tr->current_trace->use_max_tr) { |
debdd57f HT |
5760 | ret = -EBUSY; |
5761 | goto out; | |
5762 | } | |
5763 | ||
5764 | switch (val) { | |
5765 | case 0: | |
f1affcaa SRRH |
5766 | if (iter->cpu_file != RING_BUFFER_ALL_CPUS) { |
5767 | ret = -EINVAL; | |
5768 | break; | |
debdd57f | 5769 | } |
3209cff4 SRRH |
5770 | if (tr->allocated_snapshot) |
5771 | free_snapshot(tr); | |
debdd57f HT |
5772 | break; |
5773 | case 1: | |
f1affcaa SRRH |
5774 | /* Only allow per-cpu swap if the ring buffer supports it */ |
5775 | #ifndef CONFIG_RING_BUFFER_ALLOW_SWAP | |
5776 | if (iter->cpu_file != RING_BUFFER_ALL_CPUS) { | |
5777 | ret = -EINVAL; | |
5778 | break; | |
5779 | } | |
5780 | #endif | |
45ad21ca | 5781 | if (!tr->allocated_snapshot) { |
3209cff4 | 5782 | ret = alloc_snapshot(tr); |
debdd57f HT |
5783 | if (ret < 0) |
5784 | break; | |
debdd57f | 5785 | } |
debdd57f HT |
5786 | local_irq_disable(); |
5787 | /* Now, we're going to swap */ | |
f1affcaa | 5788 | if (iter->cpu_file == RING_BUFFER_ALL_CPUS) |
ce9bae55 | 5789 | update_max_tr(tr, current, smp_processor_id()); |
f1affcaa | 5790 | else |
ce9bae55 | 5791 | update_max_tr_single(tr, current, iter->cpu_file); |
debdd57f HT |
5792 | local_irq_enable(); |
5793 | break; | |
5794 | default: | |
45ad21ca | 5795 | if (tr->allocated_snapshot) { |
f1affcaa SRRH |
5796 | if (iter->cpu_file == RING_BUFFER_ALL_CPUS) |
5797 | tracing_reset_online_cpus(&tr->max_buffer); | |
5798 | else | |
5799 | tracing_reset(&tr->max_buffer, iter->cpu_file); | |
5800 | } | |
debdd57f HT |
5801 | break; |
5802 | } | |
5803 | ||
5804 | if (ret >= 0) { | |
5805 | *ppos += cnt; | |
5806 | ret = cnt; | |
5807 | } | |
5808 | out: | |
5809 | mutex_unlock(&trace_types_lock); | |
5810 | return ret; | |
5811 | } | |
2b6080f2 SR |
5812 | |
5813 | static int tracing_snapshot_release(struct inode *inode, struct file *file) | |
5814 | { | |
5815 | struct seq_file *m = file->private_data; | |
ff451961 SRRH |
5816 | int ret; |
5817 | ||
5818 | ret = tracing_release(inode, file); | |
2b6080f2 SR |
5819 | |
5820 | if (file->f_mode & FMODE_READ) | |
ff451961 | 5821 | return ret; |
2b6080f2 SR |
5822 | |
5823 | /* If write only, the seq_file is just a stub */ | |
5824 | if (m) | |
5825 | kfree(m->private); | |
5826 | kfree(m); | |
5827 | ||
5828 | return 0; | |
5829 | } | |
5830 | ||
6de58e62 SRRH |
5831 | static int tracing_buffers_open(struct inode *inode, struct file *filp); |
5832 | static ssize_t tracing_buffers_read(struct file *filp, char __user *ubuf, | |
5833 | size_t count, loff_t *ppos); | |
5834 | static int tracing_buffers_release(struct inode *inode, struct file *file); | |
5835 | static ssize_t tracing_buffers_splice_read(struct file *file, loff_t *ppos, | |
5836 | struct pipe_inode_info *pipe, size_t len, unsigned int flags); | |
5837 | ||
5838 | static int snapshot_raw_open(struct inode *inode, struct file *filp) | |
5839 | { | |
5840 | struct ftrace_buffer_info *info; | |
5841 | int ret; | |
5842 | ||
5843 | ret = tracing_buffers_open(inode, filp); | |
5844 | if (ret < 0) | |
5845 | return ret; | |
5846 | ||
5847 | info = filp->private_data; | |
5848 | ||
5849 | if (info->iter.trace->use_max_tr) { | |
5850 | tracing_buffers_release(inode, filp); | |
5851 | return -EBUSY; | |
5852 | } | |
5853 | ||
5854 | info->iter.snapshot = true; | |
5855 | info->iter.trace_buffer = &info->iter.tr->max_buffer; | |
5856 | ||
5857 | return ret; | |
5858 | } | |
5859 | ||
debdd57f HT |
5860 | #endif /* CONFIG_TRACER_SNAPSHOT */ |
5861 | ||
5862 | ||
6508fa76 SF |
5863 | static const struct file_operations tracing_thresh_fops = { |
5864 | .open = tracing_open_generic, | |
5865 | .read = tracing_thresh_read, | |
5866 | .write = tracing_thresh_write, | |
5867 | .llseek = generic_file_llseek, | |
5868 | }; | |
5869 | ||
e428abbb | 5870 | #ifdef CONFIG_TRACER_MAX_TRACE |
5e2336a0 | 5871 | static const struct file_operations tracing_max_lat_fops = { |
4bf39a94 IM |
5872 | .open = tracing_open_generic, |
5873 | .read = tracing_max_lat_read, | |
5874 | .write = tracing_max_lat_write, | |
b444786f | 5875 | .llseek = generic_file_llseek, |
bc0c38d1 | 5876 | }; |
e428abbb | 5877 | #endif |
bc0c38d1 | 5878 | |
5e2336a0 | 5879 | static const struct file_operations set_tracer_fops = { |
4bf39a94 IM |
5880 | .open = tracing_open_generic, |
5881 | .read = tracing_set_trace_read, | |
5882 | .write = tracing_set_trace_write, | |
b444786f | 5883 | .llseek = generic_file_llseek, |
bc0c38d1 SR |
5884 | }; |
5885 | ||
5e2336a0 | 5886 | static const struct file_operations tracing_pipe_fops = { |
4bf39a94 | 5887 | .open = tracing_open_pipe, |
2a2cc8f7 | 5888 | .poll = tracing_poll_pipe, |
4bf39a94 | 5889 | .read = tracing_read_pipe, |
3c56819b | 5890 | .splice_read = tracing_splice_read_pipe, |
4bf39a94 | 5891 | .release = tracing_release_pipe, |
b444786f | 5892 | .llseek = no_llseek, |
b3806b43 SR |
5893 | }; |
5894 | ||
5e2336a0 | 5895 | static const struct file_operations tracing_entries_fops = { |
0bc392ee | 5896 | .open = tracing_open_generic_tr, |
a98a3c3f SR |
5897 | .read = tracing_entries_read, |
5898 | .write = tracing_entries_write, | |
b444786f | 5899 | .llseek = generic_file_llseek, |
0bc392ee | 5900 | .release = tracing_release_generic_tr, |
a98a3c3f SR |
5901 | }; |
5902 | ||
f81ab074 | 5903 | static const struct file_operations tracing_total_entries_fops = { |
7b85af63 | 5904 | .open = tracing_open_generic_tr, |
f81ab074 VN |
5905 | .read = tracing_total_entries_read, |
5906 | .llseek = generic_file_llseek, | |
7b85af63 | 5907 | .release = tracing_release_generic_tr, |
f81ab074 VN |
5908 | }; |
5909 | ||
4f271a2a | 5910 | static const struct file_operations tracing_free_buffer_fops = { |
7b85af63 | 5911 | .open = tracing_open_generic_tr, |
4f271a2a VN |
5912 | .write = tracing_free_buffer_write, |
5913 | .release = tracing_free_buffer_release, | |
5914 | }; | |
5915 | ||
5e2336a0 | 5916 | static const struct file_operations tracing_mark_fops = { |
7b85af63 | 5917 | .open = tracing_open_generic_tr, |
5bf9a1ee | 5918 | .write = tracing_mark_write, |
b444786f | 5919 | .llseek = generic_file_llseek, |
7b85af63 | 5920 | .release = tracing_release_generic_tr, |
5bf9a1ee PP |
5921 | }; |
5922 | ||
5079f326 | 5923 | static const struct file_operations trace_clock_fops = { |
13f16d20 LZ |
5924 | .open = tracing_clock_open, |
5925 | .read = seq_read, | |
5926 | .llseek = seq_lseek, | |
7b85af63 | 5927 | .release = tracing_single_release_tr, |
5079f326 Z |
5928 | .write = tracing_clock_write, |
5929 | }; | |
5930 | ||
debdd57f HT |
5931 | #ifdef CONFIG_TRACER_SNAPSHOT |
5932 | static const struct file_operations snapshot_fops = { | |
5933 | .open = tracing_snapshot_open, | |
5934 | .read = seq_read, | |
5935 | .write = tracing_snapshot_write, | |
098c879e | 5936 | .llseek = tracing_lseek, |
2b6080f2 | 5937 | .release = tracing_snapshot_release, |
debdd57f | 5938 | }; |
debdd57f | 5939 | |
6de58e62 SRRH |
5940 | static const struct file_operations snapshot_raw_fops = { |
5941 | .open = snapshot_raw_open, | |
5942 | .read = tracing_buffers_read, | |
5943 | .release = tracing_buffers_release, | |
5944 | .splice_read = tracing_buffers_splice_read, | |
5945 | .llseek = no_llseek, | |
2cadf913 SR |
5946 | }; |
5947 | ||
6de58e62 SRRH |
5948 | #endif /* CONFIG_TRACER_SNAPSHOT */ |
5949 | ||
2cadf913 SR |
5950 | static int tracing_buffers_open(struct inode *inode, struct file *filp) |
5951 | { | |
46ef2be0 | 5952 | struct trace_array *tr = inode->i_private; |
2cadf913 | 5953 | struct ftrace_buffer_info *info; |
7b85af63 | 5954 | int ret; |
2cadf913 SR |
5955 | |
5956 | if (tracing_disabled) | |
5957 | return -ENODEV; | |
5958 | ||
7b85af63 SRRH |
5959 | if (trace_array_get(tr) < 0) |
5960 | return -ENODEV; | |
5961 | ||
2cadf913 | 5962 | info = kzalloc(sizeof(*info), GFP_KERNEL); |
7b85af63 SRRH |
5963 | if (!info) { |
5964 | trace_array_put(tr); | |
2cadf913 | 5965 | return -ENOMEM; |
7b85af63 | 5966 | } |
2cadf913 | 5967 | |
a695cb58 SRRH |
5968 | mutex_lock(&trace_types_lock); |
5969 | ||
cc60cdc9 | 5970 | info->iter.tr = tr; |
46ef2be0 | 5971 | info->iter.cpu_file = tracing_get_cpu(inode); |
b627344f | 5972 | info->iter.trace = tr->current_trace; |
12883efb | 5973 | info->iter.trace_buffer = &tr->trace_buffer; |
cc60cdc9 | 5974 | info->spare = NULL; |
2cadf913 | 5975 | /* Force reading ring buffer for first read */ |
cc60cdc9 | 5976 | info->read = (unsigned int)-1; |
2cadf913 SR |
5977 | |
5978 | filp->private_data = info; | |
5979 | ||
cf6ab6d9 SRRH |
5980 | tr->current_trace->ref++; |
5981 | ||
a695cb58 SRRH |
5982 | mutex_unlock(&trace_types_lock); |
5983 | ||
7b85af63 SRRH |
5984 | ret = nonseekable_open(inode, filp); |
5985 | if (ret < 0) | |
5986 | trace_array_put(tr); | |
5987 | ||
5988 | return ret; | |
2cadf913 SR |
5989 | } |
5990 | ||
cc60cdc9 SR |
5991 | static unsigned int |
5992 | tracing_buffers_poll(struct file *filp, poll_table *poll_table) | |
5993 | { | |
5994 | struct ftrace_buffer_info *info = filp->private_data; | |
5995 | struct trace_iterator *iter = &info->iter; | |
5996 | ||
5997 | return trace_poll(iter, filp, poll_table); | |
5998 | } | |
5999 | ||
2cadf913 SR |
6000 | static ssize_t |
6001 | tracing_buffers_read(struct file *filp, char __user *ubuf, | |
6002 | size_t count, loff_t *ppos) | |
6003 | { | |
6004 | struct ftrace_buffer_info *info = filp->private_data; | |
cc60cdc9 | 6005 | struct trace_iterator *iter = &info->iter; |
2cadf913 | 6006 | ssize_t ret; |
6de58e62 | 6007 | ssize_t size; |
2cadf913 | 6008 | |
2dc5d12b SR |
6009 | if (!count) |
6010 | return 0; | |
6011 | ||
6de58e62 | 6012 | #ifdef CONFIG_TRACER_MAX_TRACE |
d716ff71 SRRH |
6013 | if (iter->snapshot && iter->tr->current_trace->use_max_tr) |
6014 | return -EBUSY; | |
6de58e62 SRRH |
6015 | #endif |
6016 | ||
ddd538f3 | 6017 | if (!info->spare) |
12883efb SRRH |
6018 | info->spare = ring_buffer_alloc_read_page(iter->trace_buffer->buffer, |
6019 | iter->cpu_file); | |
ddd538f3 | 6020 | if (!info->spare) |
d716ff71 | 6021 | return -ENOMEM; |
ddd538f3 | 6022 | |
2cadf913 SR |
6023 | /* Do we have previous read data to read? */ |
6024 | if (info->read < PAGE_SIZE) | |
6025 | goto read; | |
6026 | ||
b627344f | 6027 | again: |
cc60cdc9 | 6028 | trace_access_lock(iter->cpu_file); |
12883efb | 6029 | ret = ring_buffer_read_page(iter->trace_buffer->buffer, |
2cadf913 SR |
6030 | &info->spare, |
6031 | count, | |
cc60cdc9 SR |
6032 | iter->cpu_file, 0); |
6033 | trace_access_unlock(iter->cpu_file); | |
2cadf913 | 6034 | |
b627344f SR |
6035 | if (ret < 0) { |
6036 | if (trace_empty(iter)) { | |
d716ff71 SRRH |
6037 | if ((filp->f_flags & O_NONBLOCK)) |
6038 | return -EAGAIN; | |
6039 | ||
e30f53aa | 6040 | ret = wait_on_pipe(iter, false); |
d716ff71 SRRH |
6041 | if (ret) |
6042 | return ret; | |
6043 | ||
b627344f SR |
6044 | goto again; |
6045 | } | |
d716ff71 | 6046 | return 0; |
b627344f | 6047 | } |
436fc280 | 6048 | |
436fc280 | 6049 | info->read = 0; |
b627344f | 6050 | read: |
2cadf913 SR |
6051 | size = PAGE_SIZE - info->read; |
6052 | if (size > count) | |
6053 | size = count; | |
6054 | ||
6055 | ret = copy_to_user(ubuf, info->spare + info->read, size); | |
d716ff71 SRRH |
6056 | if (ret == size) |
6057 | return -EFAULT; | |
6058 | ||
2dc5d12b SR |
6059 | size -= ret; |
6060 | ||
2cadf913 SR |
6061 | *ppos += size; |
6062 | info->read += size; | |
6063 | ||
6064 | return size; | |
6065 | } | |
6066 | ||
6067 | static int tracing_buffers_release(struct inode *inode, struct file *file) | |
6068 | { | |
6069 | struct ftrace_buffer_info *info = file->private_data; | |
cc60cdc9 | 6070 | struct trace_iterator *iter = &info->iter; |
2cadf913 | 6071 | |
a695cb58 SRRH |
6072 | mutex_lock(&trace_types_lock); |
6073 | ||
cf6ab6d9 SRRH |
6074 | iter->tr->current_trace->ref--; |
6075 | ||
ff451961 | 6076 | __trace_array_put(iter->tr); |
2cadf913 | 6077 | |
ddd538f3 | 6078 | if (info->spare) |
12883efb | 6079 | ring_buffer_free_read_page(iter->trace_buffer->buffer, info->spare); |
2cadf913 SR |
6080 | kfree(info); |
6081 | ||
a695cb58 SRRH |
6082 | mutex_unlock(&trace_types_lock); |
6083 | ||
2cadf913 SR |
6084 | return 0; |
6085 | } | |
6086 | ||
6087 | struct buffer_ref { | |
6088 | struct ring_buffer *buffer; | |
6089 | void *page; | |
6090 | int ref; | |
6091 | }; | |
6092 | ||
6093 | static void buffer_pipe_buf_release(struct pipe_inode_info *pipe, | |
6094 | struct pipe_buffer *buf) | |
6095 | { | |
6096 | struct buffer_ref *ref = (struct buffer_ref *)buf->private; | |
6097 | ||
6098 | if (--ref->ref) | |
6099 | return; | |
6100 | ||
6101 | ring_buffer_free_read_page(ref->buffer, ref->page); | |
6102 | kfree(ref); | |
6103 | buf->private = 0; | |
6104 | } | |
6105 | ||
2cadf913 SR |
6106 | static void buffer_pipe_buf_get(struct pipe_inode_info *pipe, |
6107 | struct pipe_buffer *buf) | |
6108 | { | |
6109 | struct buffer_ref *ref = (struct buffer_ref *)buf->private; | |
6110 | ||
6111 | ref->ref++; | |
6112 | } | |
6113 | ||
6114 | /* Pipe buffer operations for a buffer. */ | |
28dfef8f | 6115 | static const struct pipe_buf_operations buffer_pipe_buf_ops = { |
2cadf913 | 6116 | .can_merge = 0, |
2cadf913 SR |
6117 | .confirm = generic_pipe_buf_confirm, |
6118 | .release = buffer_pipe_buf_release, | |
d55cb6cf | 6119 | .steal = generic_pipe_buf_steal, |
2cadf913 SR |
6120 | .get = buffer_pipe_buf_get, |
6121 | }; | |
6122 | ||
6123 | /* | |
6124 | * Callback from splice_to_pipe(), if we need to release some pages | |
6125 | * at the end of the spd in case we error'ed out in filling the pipe. | |
6126 | */ | |
6127 | static void buffer_spd_release(struct splice_pipe_desc *spd, unsigned int i) | |
6128 | { | |
6129 | struct buffer_ref *ref = | |
6130 | (struct buffer_ref *)spd->partial[i].private; | |
6131 | ||
6132 | if (--ref->ref) | |
6133 | return; | |
6134 | ||
6135 | ring_buffer_free_read_page(ref->buffer, ref->page); | |
6136 | kfree(ref); | |
6137 | spd->partial[i].private = 0; | |
6138 | } | |
6139 | ||
6140 | static ssize_t | |
6141 | tracing_buffers_splice_read(struct file *file, loff_t *ppos, | |
6142 | struct pipe_inode_info *pipe, size_t len, | |
6143 | unsigned int flags) | |
6144 | { | |
6145 | struct ftrace_buffer_info *info = file->private_data; | |
cc60cdc9 | 6146 | struct trace_iterator *iter = &info->iter; |
35f3d14d JA |
6147 | struct partial_page partial_def[PIPE_DEF_BUFFERS]; |
6148 | struct page *pages_def[PIPE_DEF_BUFFERS]; | |
2cadf913 | 6149 | struct splice_pipe_desc spd = { |
35f3d14d JA |
6150 | .pages = pages_def, |
6151 | .partial = partial_def, | |
047fe360 | 6152 | .nr_pages_max = PIPE_DEF_BUFFERS, |
2cadf913 SR |
6153 | .flags = flags, |
6154 | .ops = &buffer_pipe_buf_ops, | |
6155 | .spd_release = buffer_spd_release, | |
6156 | }; | |
6157 | struct buffer_ref *ref; | |
93459c6c | 6158 | int entries, size, i; |
07906da7 | 6159 | ssize_t ret = 0; |
2cadf913 | 6160 | |
6de58e62 | 6161 | #ifdef CONFIG_TRACER_MAX_TRACE |
d716ff71 SRRH |
6162 | if (iter->snapshot && iter->tr->current_trace->use_max_tr) |
6163 | return -EBUSY; | |
6de58e62 SRRH |
6164 | #endif |
6165 | ||
d716ff71 SRRH |
6166 | if (splice_grow_spd(pipe, &spd)) |
6167 | return -ENOMEM; | |
35f3d14d | 6168 | |
d716ff71 SRRH |
6169 | if (*ppos & (PAGE_SIZE - 1)) |
6170 | return -EINVAL; | |
93cfb3c9 LJ |
6171 | |
6172 | if (len & (PAGE_SIZE - 1)) { | |
d716ff71 SRRH |
6173 | if (len < PAGE_SIZE) |
6174 | return -EINVAL; | |
93cfb3c9 LJ |
6175 | len &= PAGE_MASK; |
6176 | } | |
6177 | ||
cc60cdc9 SR |
6178 | again: |
6179 | trace_access_lock(iter->cpu_file); | |
12883efb | 6180 | entries = ring_buffer_entries_cpu(iter->trace_buffer->buffer, iter->cpu_file); |
93459c6c | 6181 | |
a786c06d | 6182 | for (i = 0; i < spd.nr_pages_max && len && entries; i++, len -= PAGE_SIZE) { |
2cadf913 SR |
6183 | struct page *page; |
6184 | int r; | |
6185 | ||
6186 | ref = kzalloc(sizeof(*ref), GFP_KERNEL); | |
07906da7 RV |
6187 | if (!ref) { |
6188 | ret = -ENOMEM; | |
2cadf913 | 6189 | break; |
07906da7 | 6190 | } |
2cadf913 | 6191 | |
7267fa68 | 6192 | ref->ref = 1; |
12883efb | 6193 | ref->buffer = iter->trace_buffer->buffer; |
cc60cdc9 | 6194 | ref->page = ring_buffer_alloc_read_page(ref->buffer, iter->cpu_file); |
2cadf913 | 6195 | if (!ref->page) { |
07906da7 | 6196 | ret = -ENOMEM; |
2cadf913 SR |
6197 | kfree(ref); |
6198 | break; | |
6199 | } | |
6200 | ||
6201 | r = ring_buffer_read_page(ref->buffer, &ref->page, | |
cc60cdc9 | 6202 | len, iter->cpu_file, 1); |
2cadf913 | 6203 | if (r < 0) { |
7ea59064 | 6204 | ring_buffer_free_read_page(ref->buffer, ref->page); |
2cadf913 SR |
6205 | kfree(ref); |
6206 | break; | |
6207 | } | |
6208 | ||
6209 | /* | |
6210 | * zero out any left over data, this is going to | |
6211 | * user land. | |
6212 | */ | |
6213 | size = ring_buffer_page_len(ref->page); | |
6214 | if (size < PAGE_SIZE) | |
6215 | memset(ref->page + size, 0, PAGE_SIZE - size); | |
6216 | ||
6217 | page = virt_to_page(ref->page); | |
6218 | ||
6219 | spd.pages[i] = page; | |
6220 | spd.partial[i].len = PAGE_SIZE; | |
6221 | spd.partial[i].offset = 0; | |
6222 | spd.partial[i].private = (unsigned long)ref; | |
6223 | spd.nr_pages++; | |
93cfb3c9 | 6224 | *ppos += PAGE_SIZE; |
93459c6c | 6225 | |
12883efb | 6226 | entries = ring_buffer_entries_cpu(iter->trace_buffer->buffer, iter->cpu_file); |
2cadf913 SR |
6227 | } |
6228 | ||
cc60cdc9 | 6229 | trace_access_unlock(iter->cpu_file); |
2cadf913 SR |
6230 | spd.nr_pages = i; |
6231 | ||
6232 | /* did we read anything? */ | |
6233 | if (!spd.nr_pages) { | |
07906da7 | 6234 | if (ret) |
d716ff71 SRRH |
6235 | return ret; |
6236 | ||
6237 | if ((file->f_flags & O_NONBLOCK) || (flags & SPLICE_F_NONBLOCK)) | |
6238 | return -EAGAIN; | |
07906da7 | 6239 | |
e30f53aa | 6240 | ret = wait_on_pipe(iter, true); |
8b8b3683 | 6241 | if (ret) |
d716ff71 | 6242 | return ret; |
e30f53aa | 6243 | |
cc60cdc9 | 6244 | goto again; |
2cadf913 SR |
6245 | } |
6246 | ||
6247 | ret = splice_to_pipe(pipe, &spd); | |
047fe360 | 6248 | splice_shrink_spd(&spd); |
6de58e62 | 6249 | |
2cadf913 SR |
6250 | return ret; |
6251 | } | |
6252 | ||
6253 | static const struct file_operations tracing_buffers_fops = { | |
6254 | .open = tracing_buffers_open, | |
6255 | .read = tracing_buffers_read, | |
cc60cdc9 | 6256 | .poll = tracing_buffers_poll, |
2cadf913 SR |
6257 | .release = tracing_buffers_release, |
6258 | .splice_read = tracing_buffers_splice_read, | |
6259 | .llseek = no_llseek, | |
6260 | }; | |
6261 | ||
c8d77183 SR |
6262 | static ssize_t |
6263 | tracing_stats_read(struct file *filp, char __user *ubuf, | |
6264 | size_t count, loff_t *ppos) | |
6265 | { | |
4d3435b8 ON |
6266 | struct inode *inode = file_inode(filp); |
6267 | struct trace_array *tr = inode->i_private; | |
12883efb | 6268 | struct trace_buffer *trace_buf = &tr->trace_buffer; |
4d3435b8 | 6269 | int cpu = tracing_get_cpu(inode); |
c8d77183 SR |
6270 | struct trace_seq *s; |
6271 | unsigned long cnt; | |
c64e148a VN |
6272 | unsigned long long t; |
6273 | unsigned long usec_rem; | |
c8d77183 | 6274 | |
e4f2d10f | 6275 | s = kmalloc(sizeof(*s), GFP_KERNEL); |
c8d77183 | 6276 | if (!s) |
a646365c | 6277 | return -ENOMEM; |
c8d77183 SR |
6278 | |
6279 | trace_seq_init(s); | |
6280 | ||
12883efb | 6281 | cnt = ring_buffer_entries_cpu(trace_buf->buffer, cpu); |
c8d77183 SR |
6282 | trace_seq_printf(s, "entries: %ld\n", cnt); |
6283 | ||
12883efb | 6284 | cnt = ring_buffer_overrun_cpu(trace_buf->buffer, cpu); |
c8d77183 SR |
6285 | trace_seq_printf(s, "overrun: %ld\n", cnt); |
6286 | ||
12883efb | 6287 | cnt = ring_buffer_commit_overrun_cpu(trace_buf->buffer, cpu); |
c8d77183 SR |
6288 | trace_seq_printf(s, "commit overrun: %ld\n", cnt); |
6289 | ||
12883efb | 6290 | cnt = ring_buffer_bytes_cpu(trace_buf->buffer, cpu); |
c64e148a VN |
6291 | trace_seq_printf(s, "bytes: %ld\n", cnt); |
6292 | ||
58e8eedf | 6293 | if (trace_clocks[tr->clock_id].in_ns) { |
11043d8b | 6294 | /* local or global for trace_clock */ |
12883efb | 6295 | t = ns2usecs(ring_buffer_oldest_event_ts(trace_buf->buffer, cpu)); |
11043d8b YY |
6296 | usec_rem = do_div(t, USEC_PER_SEC); |
6297 | trace_seq_printf(s, "oldest event ts: %5llu.%06lu\n", | |
6298 | t, usec_rem); | |
6299 | ||
12883efb | 6300 | t = ns2usecs(ring_buffer_time_stamp(trace_buf->buffer, cpu)); |
11043d8b YY |
6301 | usec_rem = do_div(t, USEC_PER_SEC); |
6302 | trace_seq_printf(s, "now ts: %5llu.%06lu\n", t, usec_rem); | |
6303 | } else { | |
6304 | /* counter or tsc mode for trace_clock */ | |
6305 | trace_seq_printf(s, "oldest event ts: %llu\n", | |
12883efb | 6306 | ring_buffer_oldest_event_ts(trace_buf->buffer, cpu)); |
c64e148a | 6307 | |
11043d8b | 6308 | trace_seq_printf(s, "now ts: %llu\n", |
12883efb | 6309 | ring_buffer_time_stamp(trace_buf->buffer, cpu)); |
11043d8b | 6310 | } |
c64e148a | 6311 | |
12883efb | 6312 | cnt = ring_buffer_dropped_events_cpu(trace_buf->buffer, cpu); |
884bfe89 SP |
6313 | trace_seq_printf(s, "dropped events: %ld\n", cnt); |
6314 | ||
12883efb | 6315 | cnt = ring_buffer_read_events_cpu(trace_buf->buffer, cpu); |
ad964704 SRRH |
6316 | trace_seq_printf(s, "read events: %ld\n", cnt); |
6317 | ||
5ac48378 SRRH |
6318 | count = simple_read_from_buffer(ubuf, count, ppos, |
6319 | s->buffer, trace_seq_used(s)); | |
c8d77183 SR |
6320 | |
6321 | kfree(s); | |
6322 | ||
6323 | return count; | |
6324 | } | |
6325 | ||
6326 | static const struct file_operations tracing_stats_fops = { | |
4d3435b8 | 6327 | .open = tracing_open_generic_tr, |
c8d77183 | 6328 | .read = tracing_stats_read, |
b444786f | 6329 | .llseek = generic_file_llseek, |
4d3435b8 | 6330 | .release = tracing_release_generic_tr, |
c8d77183 SR |
6331 | }; |
6332 | ||
bc0c38d1 SR |
6333 | #ifdef CONFIG_DYNAMIC_FTRACE |
6334 | ||
b807c3d0 SR |
6335 | int __weak ftrace_arch_read_dyn_info(char *buf, int size) |
6336 | { | |
6337 | return 0; | |
6338 | } | |
6339 | ||
bc0c38d1 | 6340 | static ssize_t |
b807c3d0 | 6341 | tracing_read_dyn_info(struct file *filp, char __user *ubuf, |
bc0c38d1 SR |
6342 | size_t cnt, loff_t *ppos) |
6343 | { | |
a26a2a27 SR |
6344 | static char ftrace_dyn_info_buffer[1024]; |
6345 | static DEFINE_MUTEX(dyn_info_mutex); | |
bc0c38d1 | 6346 | unsigned long *p = filp->private_data; |
b807c3d0 | 6347 | char *buf = ftrace_dyn_info_buffer; |
a26a2a27 | 6348 | int size = ARRAY_SIZE(ftrace_dyn_info_buffer); |
bc0c38d1 SR |
6349 | int r; |
6350 | ||
b807c3d0 SR |
6351 | mutex_lock(&dyn_info_mutex); |
6352 | r = sprintf(buf, "%ld ", *p); | |
4bf39a94 | 6353 | |
a26a2a27 | 6354 | r += ftrace_arch_read_dyn_info(buf+r, (size-1)-r); |
b807c3d0 SR |
6355 | buf[r++] = '\n'; |
6356 | ||
6357 | r = simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
6358 | ||
6359 | mutex_unlock(&dyn_info_mutex); | |
6360 | ||
6361 | return r; | |
bc0c38d1 SR |
6362 | } |
6363 | ||
5e2336a0 | 6364 | static const struct file_operations tracing_dyn_info_fops = { |
4bf39a94 | 6365 | .open = tracing_open_generic, |
b807c3d0 | 6366 | .read = tracing_read_dyn_info, |
b444786f | 6367 | .llseek = generic_file_llseek, |
bc0c38d1 | 6368 | }; |
77fd5c15 | 6369 | #endif /* CONFIG_DYNAMIC_FTRACE */ |
bc0c38d1 | 6370 | |
77fd5c15 SRRH |
6371 | #if defined(CONFIG_TRACER_SNAPSHOT) && defined(CONFIG_DYNAMIC_FTRACE) |
6372 | static void | |
6373 | ftrace_snapshot(unsigned long ip, unsigned long parent_ip, void **data) | |
6374 | { | |
6375 | tracing_snapshot(); | |
6376 | } | |
bc0c38d1 | 6377 | |
77fd5c15 SRRH |
6378 | static void |
6379 | ftrace_count_snapshot(unsigned long ip, unsigned long parent_ip, void **data) | |
bc0c38d1 | 6380 | { |
77fd5c15 SRRH |
6381 | unsigned long *count = (long *)data; |
6382 | ||
6383 | if (!*count) | |
6384 | return; | |
bc0c38d1 | 6385 | |
77fd5c15 SRRH |
6386 | if (*count != -1) |
6387 | (*count)--; | |
6388 | ||
6389 | tracing_snapshot(); | |
6390 | } | |
6391 | ||
6392 | static int | |
6393 | ftrace_snapshot_print(struct seq_file *m, unsigned long ip, | |
6394 | struct ftrace_probe_ops *ops, void *data) | |
6395 | { | |
6396 | long count = (long)data; | |
6397 | ||
6398 | seq_printf(m, "%ps:", (void *)ip); | |
6399 | ||
fa6f0cc7 | 6400 | seq_puts(m, "snapshot"); |
77fd5c15 SRRH |
6401 | |
6402 | if (count == -1) | |
fa6f0cc7 | 6403 | seq_puts(m, ":unlimited\n"); |
77fd5c15 SRRH |
6404 | else |
6405 | seq_printf(m, ":count=%ld\n", count); | |
6406 | ||
6407 | return 0; | |
6408 | } | |
6409 | ||
6410 | static struct ftrace_probe_ops snapshot_probe_ops = { | |
6411 | .func = ftrace_snapshot, | |
6412 | .print = ftrace_snapshot_print, | |
6413 | }; | |
6414 | ||
6415 | static struct ftrace_probe_ops snapshot_count_probe_ops = { | |
6416 | .func = ftrace_count_snapshot, | |
6417 | .print = ftrace_snapshot_print, | |
6418 | }; | |
6419 | ||
6420 | static int | |
6421 | ftrace_trace_snapshot_callback(struct ftrace_hash *hash, | |
6422 | char *glob, char *cmd, char *param, int enable) | |
6423 | { | |
6424 | struct ftrace_probe_ops *ops; | |
6425 | void *count = (void *)-1; | |
6426 | char *number; | |
6427 | int ret; | |
6428 | ||
6429 | /* hash funcs only work with set_ftrace_filter */ | |
6430 | if (!enable) | |
6431 | return -EINVAL; | |
6432 | ||
6433 | ops = param ? &snapshot_count_probe_ops : &snapshot_probe_ops; | |
6434 | ||
6435 | if (glob[0] == '!') { | |
6436 | unregister_ftrace_function_probe_func(glob+1, ops); | |
6437 | return 0; | |
6438 | } | |
6439 | ||
6440 | if (!param) | |
6441 | goto out_reg; | |
6442 | ||
6443 | number = strsep(¶m, ":"); | |
6444 | ||
6445 | if (!strlen(number)) | |
6446 | goto out_reg; | |
6447 | ||
6448 | /* | |
6449 | * We use the callback data field (which is a pointer) | |
6450 | * as our counter. | |
6451 | */ | |
6452 | ret = kstrtoul(number, 0, (unsigned long *)&count); | |
6453 | if (ret) | |
6454 | return ret; | |
6455 | ||
6456 | out_reg: | |
6457 | ret = register_ftrace_function_probe(glob, ops, count); | |
6458 | ||
6459 | if (ret >= 0) | |
6460 | alloc_snapshot(&global_trace); | |
6461 | ||
6462 | return ret < 0 ? ret : 0; | |
6463 | } | |
6464 | ||
6465 | static struct ftrace_func_command ftrace_snapshot_cmd = { | |
6466 | .name = "snapshot", | |
6467 | .func = ftrace_trace_snapshot_callback, | |
6468 | }; | |
6469 | ||
38de93ab | 6470 | static __init int register_snapshot_cmd(void) |
77fd5c15 SRRH |
6471 | { |
6472 | return register_ftrace_command(&ftrace_snapshot_cmd); | |
6473 | } | |
6474 | #else | |
38de93ab | 6475 | static inline __init int register_snapshot_cmd(void) { return 0; } |
77fd5c15 | 6476 | #endif /* defined(CONFIG_TRACER_SNAPSHOT) && defined(CONFIG_DYNAMIC_FTRACE) */ |
bc0c38d1 | 6477 | |
7eeafbca | 6478 | static struct dentry *tracing_get_dentry(struct trace_array *tr) |
bc0c38d1 | 6479 | { |
8434dc93 SRRH |
6480 | if (WARN_ON(!tr->dir)) |
6481 | return ERR_PTR(-ENODEV); | |
6482 | ||
6483 | /* Top directory uses NULL as the parent */ | |
6484 | if (tr->flags & TRACE_ARRAY_FL_GLOBAL) | |
6485 | return NULL; | |
6486 | ||
6487 | /* All sub buffers have a descriptor */ | |
2b6080f2 | 6488 | return tr->dir; |
bc0c38d1 SR |
6489 | } |
6490 | ||
2b6080f2 | 6491 | static struct dentry *tracing_dentry_percpu(struct trace_array *tr, int cpu) |
b04cc6b1 | 6492 | { |
b04cc6b1 FW |
6493 | struct dentry *d_tracer; |
6494 | ||
2b6080f2 SR |
6495 | if (tr->percpu_dir) |
6496 | return tr->percpu_dir; | |
b04cc6b1 | 6497 | |
7eeafbca | 6498 | d_tracer = tracing_get_dentry(tr); |
14a5ae40 | 6499 | if (IS_ERR(d_tracer)) |
b04cc6b1 FW |
6500 | return NULL; |
6501 | ||
8434dc93 | 6502 | tr->percpu_dir = tracefs_create_dir("per_cpu", d_tracer); |
b04cc6b1 | 6503 | |
2b6080f2 | 6504 | WARN_ONCE(!tr->percpu_dir, |
8434dc93 | 6505 | "Could not create tracefs directory 'per_cpu/%d'\n", cpu); |
b04cc6b1 | 6506 | |
2b6080f2 | 6507 | return tr->percpu_dir; |
b04cc6b1 FW |
6508 | } |
6509 | ||
649e9c70 ON |
6510 | static struct dentry * |
6511 | trace_create_cpu_file(const char *name, umode_t mode, struct dentry *parent, | |
6512 | void *data, long cpu, const struct file_operations *fops) | |
6513 | { | |
6514 | struct dentry *ret = trace_create_file(name, mode, parent, data, fops); | |
6515 | ||
6516 | if (ret) /* See tracing_get_cpu() */ | |
7682c918 | 6517 | d_inode(ret)->i_cdev = (void *)(cpu + 1); |
649e9c70 ON |
6518 | return ret; |
6519 | } | |
6520 | ||
2b6080f2 | 6521 | static void |
8434dc93 | 6522 | tracing_init_tracefs_percpu(struct trace_array *tr, long cpu) |
b04cc6b1 | 6523 | { |
2b6080f2 | 6524 | struct dentry *d_percpu = tracing_dentry_percpu(tr, cpu); |
5452af66 | 6525 | struct dentry *d_cpu; |
dd49a38c | 6526 | char cpu_dir[30]; /* 30 characters should be more than enough */ |
b04cc6b1 | 6527 | |
0a3d7ce7 NK |
6528 | if (!d_percpu) |
6529 | return; | |
6530 | ||
dd49a38c | 6531 | snprintf(cpu_dir, 30, "cpu%ld", cpu); |
8434dc93 | 6532 | d_cpu = tracefs_create_dir(cpu_dir, d_percpu); |
8656e7a2 | 6533 | if (!d_cpu) { |
a395d6a7 | 6534 | pr_warn("Could not create tracefs '%s' entry\n", cpu_dir); |
8656e7a2 FW |
6535 | return; |
6536 | } | |
b04cc6b1 | 6537 | |
8656e7a2 | 6538 | /* per cpu trace_pipe */ |
649e9c70 | 6539 | trace_create_cpu_file("trace_pipe", 0444, d_cpu, |
15544209 | 6540 | tr, cpu, &tracing_pipe_fops); |
b04cc6b1 FW |
6541 | |
6542 | /* per cpu trace */ | |
649e9c70 | 6543 | trace_create_cpu_file("trace", 0644, d_cpu, |
6484c71c | 6544 | tr, cpu, &tracing_fops); |
7f96f93f | 6545 | |
649e9c70 | 6546 | trace_create_cpu_file("trace_pipe_raw", 0444, d_cpu, |
46ef2be0 | 6547 | tr, cpu, &tracing_buffers_fops); |
7f96f93f | 6548 | |
649e9c70 | 6549 | trace_create_cpu_file("stats", 0444, d_cpu, |
4d3435b8 | 6550 | tr, cpu, &tracing_stats_fops); |
438ced17 | 6551 | |
649e9c70 | 6552 | trace_create_cpu_file("buffer_size_kb", 0444, d_cpu, |
0bc392ee | 6553 | tr, cpu, &tracing_entries_fops); |
f1affcaa SRRH |
6554 | |
6555 | #ifdef CONFIG_TRACER_SNAPSHOT | |
649e9c70 | 6556 | trace_create_cpu_file("snapshot", 0644, d_cpu, |
6484c71c | 6557 | tr, cpu, &snapshot_fops); |
6de58e62 | 6558 | |
649e9c70 | 6559 | trace_create_cpu_file("snapshot_raw", 0444, d_cpu, |
46ef2be0 | 6560 | tr, cpu, &snapshot_raw_fops); |
f1affcaa | 6561 | #endif |
b04cc6b1 FW |
6562 | } |
6563 | ||
60a11774 SR |
6564 | #ifdef CONFIG_FTRACE_SELFTEST |
6565 | /* Let selftest have access to static functions in this file */ | |
6566 | #include "trace_selftest.c" | |
6567 | #endif | |
6568 | ||
577b785f SR |
6569 | static ssize_t |
6570 | trace_options_read(struct file *filp, char __user *ubuf, size_t cnt, | |
6571 | loff_t *ppos) | |
6572 | { | |
6573 | struct trace_option_dentry *topt = filp->private_data; | |
6574 | char *buf; | |
6575 | ||
6576 | if (topt->flags->val & topt->opt->bit) | |
6577 | buf = "1\n"; | |
6578 | else | |
6579 | buf = "0\n"; | |
6580 | ||
6581 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, 2); | |
6582 | } | |
6583 | ||
6584 | static ssize_t | |
6585 | trace_options_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
6586 | loff_t *ppos) | |
6587 | { | |
6588 | struct trace_option_dentry *topt = filp->private_data; | |
6589 | unsigned long val; | |
577b785f SR |
6590 | int ret; |
6591 | ||
22fe9b54 PH |
6592 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
6593 | if (ret) | |
577b785f SR |
6594 | return ret; |
6595 | ||
8d18eaaf LZ |
6596 | if (val != 0 && val != 1) |
6597 | return -EINVAL; | |
577b785f | 6598 | |
8d18eaaf | 6599 | if (!!(topt->flags->val & topt->opt->bit) != val) { |
577b785f | 6600 | mutex_lock(&trace_types_lock); |
8c1a49ae | 6601 | ret = __set_tracer_option(topt->tr, topt->flags, |
c757bea9 | 6602 | topt->opt, !val); |
577b785f SR |
6603 | mutex_unlock(&trace_types_lock); |
6604 | if (ret) | |
6605 | return ret; | |
577b785f SR |
6606 | } |
6607 | ||
6608 | *ppos += cnt; | |
6609 | ||
6610 | return cnt; | |
6611 | } | |
6612 | ||
6613 | ||
6614 | static const struct file_operations trace_options_fops = { | |
6615 | .open = tracing_open_generic, | |
6616 | .read = trace_options_read, | |
6617 | .write = trace_options_write, | |
b444786f | 6618 | .llseek = generic_file_llseek, |
577b785f SR |
6619 | }; |
6620 | ||
9a38a885 SRRH |
6621 | /* |
6622 | * In order to pass in both the trace_array descriptor as well as the index | |
6623 | * to the flag that the trace option file represents, the trace_array | |
6624 | * has a character array of trace_flags_index[], which holds the index | |
6625 | * of the bit for the flag it represents. index[0] == 0, index[1] == 1, etc. | |
6626 | * The address of this character array is passed to the flag option file | |
6627 | * read/write callbacks. | |
6628 | * | |
6629 | * In order to extract both the index and the trace_array descriptor, | |
6630 | * get_tr_index() uses the following algorithm. | |
6631 | * | |
6632 | * idx = *ptr; | |
6633 | * | |
6634 | * As the pointer itself contains the address of the index (remember | |
6635 | * index[1] == 1). | |
6636 | * | |
6637 | * Then to get the trace_array descriptor, by subtracting that index | |
6638 | * from the ptr, we get to the start of the index itself. | |
6639 | * | |
6640 | * ptr - idx == &index[0] | |
6641 | * | |
6642 | * Then a simple container_of() from that pointer gets us to the | |
6643 | * trace_array descriptor. | |
6644 | */ | |
6645 | static void get_tr_index(void *data, struct trace_array **ptr, | |
6646 | unsigned int *pindex) | |
6647 | { | |
6648 | *pindex = *(unsigned char *)data; | |
6649 | ||
6650 | *ptr = container_of(data - *pindex, struct trace_array, | |
6651 | trace_flags_index); | |
6652 | } | |
6653 | ||
a8259075 SR |
6654 | static ssize_t |
6655 | trace_options_core_read(struct file *filp, char __user *ubuf, size_t cnt, | |
6656 | loff_t *ppos) | |
6657 | { | |
9a38a885 SRRH |
6658 | void *tr_index = filp->private_data; |
6659 | struct trace_array *tr; | |
6660 | unsigned int index; | |
a8259075 SR |
6661 | char *buf; |
6662 | ||
9a38a885 SRRH |
6663 | get_tr_index(tr_index, &tr, &index); |
6664 | ||
6665 | if (tr->trace_flags & (1 << index)) | |
a8259075 SR |
6666 | buf = "1\n"; |
6667 | else | |
6668 | buf = "0\n"; | |
6669 | ||
6670 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, 2); | |
6671 | } | |
6672 | ||
6673 | static ssize_t | |
6674 | trace_options_core_write(struct file *filp, const char __user *ubuf, size_t cnt, | |
6675 | loff_t *ppos) | |
6676 | { | |
9a38a885 SRRH |
6677 | void *tr_index = filp->private_data; |
6678 | struct trace_array *tr; | |
6679 | unsigned int index; | |
a8259075 SR |
6680 | unsigned long val; |
6681 | int ret; | |
6682 | ||
9a38a885 SRRH |
6683 | get_tr_index(tr_index, &tr, &index); |
6684 | ||
22fe9b54 PH |
6685 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); |
6686 | if (ret) | |
a8259075 SR |
6687 | return ret; |
6688 | ||
f2d84b65 | 6689 | if (val != 0 && val != 1) |
a8259075 | 6690 | return -EINVAL; |
69d34da2 SRRH |
6691 | |
6692 | mutex_lock(&trace_types_lock); | |
2b6080f2 | 6693 | ret = set_tracer_flag(tr, 1 << index, val); |
69d34da2 | 6694 | mutex_unlock(&trace_types_lock); |
a8259075 | 6695 | |
613f04a0 SRRH |
6696 | if (ret < 0) |
6697 | return ret; | |
6698 | ||
a8259075 SR |
6699 | *ppos += cnt; |
6700 | ||
6701 | return cnt; | |
6702 | } | |
6703 | ||
a8259075 SR |
6704 | static const struct file_operations trace_options_core_fops = { |
6705 | .open = tracing_open_generic, | |
6706 | .read = trace_options_core_read, | |
6707 | .write = trace_options_core_write, | |
b444786f | 6708 | .llseek = generic_file_llseek, |
a8259075 SR |
6709 | }; |
6710 | ||
5452af66 | 6711 | struct dentry *trace_create_file(const char *name, |
f4ae40a6 | 6712 | umode_t mode, |
5452af66 FW |
6713 | struct dentry *parent, |
6714 | void *data, | |
6715 | const struct file_operations *fops) | |
6716 | { | |
6717 | struct dentry *ret; | |
6718 | ||
8434dc93 | 6719 | ret = tracefs_create_file(name, mode, parent, data, fops); |
5452af66 | 6720 | if (!ret) |
a395d6a7 | 6721 | pr_warn("Could not create tracefs '%s' entry\n", name); |
5452af66 FW |
6722 | |
6723 | return ret; | |
6724 | } | |
6725 | ||
6726 | ||
2b6080f2 | 6727 | static struct dentry *trace_options_init_dentry(struct trace_array *tr) |
a8259075 SR |
6728 | { |
6729 | struct dentry *d_tracer; | |
a8259075 | 6730 | |
2b6080f2 SR |
6731 | if (tr->options) |
6732 | return tr->options; | |
a8259075 | 6733 | |
7eeafbca | 6734 | d_tracer = tracing_get_dentry(tr); |
14a5ae40 | 6735 | if (IS_ERR(d_tracer)) |
a8259075 SR |
6736 | return NULL; |
6737 | ||
8434dc93 | 6738 | tr->options = tracefs_create_dir("options", d_tracer); |
2b6080f2 | 6739 | if (!tr->options) { |
a395d6a7 | 6740 | pr_warn("Could not create tracefs directory 'options'\n"); |
a8259075 SR |
6741 | return NULL; |
6742 | } | |
6743 | ||
2b6080f2 | 6744 | return tr->options; |
a8259075 SR |
6745 | } |
6746 | ||
577b785f | 6747 | static void |
2b6080f2 SR |
6748 | create_trace_option_file(struct trace_array *tr, |
6749 | struct trace_option_dentry *topt, | |
577b785f SR |
6750 | struct tracer_flags *flags, |
6751 | struct tracer_opt *opt) | |
6752 | { | |
6753 | struct dentry *t_options; | |
577b785f | 6754 | |
2b6080f2 | 6755 | t_options = trace_options_init_dentry(tr); |
577b785f SR |
6756 | if (!t_options) |
6757 | return; | |
6758 | ||
6759 | topt->flags = flags; | |
6760 | topt->opt = opt; | |
2b6080f2 | 6761 | topt->tr = tr; |
577b785f | 6762 | |
5452af66 | 6763 | topt->entry = trace_create_file(opt->name, 0644, t_options, topt, |
577b785f SR |
6764 | &trace_options_fops); |
6765 | ||
577b785f SR |
6766 | } |
6767 | ||
37aea98b | 6768 | static void |
2b6080f2 | 6769 | create_trace_option_files(struct trace_array *tr, struct tracer *tracer) |
577b785f SR |
6770 | { |
6771 | struct trace_option_dentry *topts; | |
37aea98b | 6772 | struct trace_options *tr_topts; |
577b785f SR |
6773 | struct tracer_flags *flags; |
6774 | struct tracer_opt *opts; | |
6775 | int cnt; | |
37aea98b | 6776 | int i; |
577b785f SR |
6777 | |
6778 | if (!tracer) | |
37aea98b | 6779 | return; |
577b785f SR |
6780 | |
6781 | flags = tracer->flags; | |
6782 | ||
6783 | if (!flags || !flags->opts) | |
37aea98b SRRH |
6784 | return; |
6785 | ||
6786 | /* | |
6787 | * If this is an instance, only create flags for tracers | |
6788 | * the instance may have. | |
6789 | */ | |
6790 | if (!trace_ok_for_array(tracer, tr)) | |
6791 | return; | |
6792 | ||
6793 | for (i = 0; i < tr->nr_topts; i++) { | |
d39cdd20 CH |
6794 | /* Make sure there's no duplicate flags. */ |
6795 | if (WARN_ON_ONCE(tr->topts[i].tracer->flags == tracer->flags)) | |
37aea98b SRRH |
6796 | return; |
6797 | } | |
577b785f SR |
6798 | |
6799 | opts = flags->opts; | |
6800 | ||
6801 | for (cnt = 0; opts[cnt].name; cnt++) | |
6802 | ; | |
6803 | ||
0cfe8245 | 6804 | topts = kcalloc(cnt + 1, sizeof(*topts), GFP_KERNEL); |
577b785f | 6805 | if (!topts) |
37aea98b SRRH |
6806 | return; |
6807 | ||
6808 | tr_topts = krealloc(tr->topts, sizeof(*tr->topts) * (tr->nr_topts + 1), | |
6809 | GFP_KERNEL); | |
6810 | if (!tr_topts) { | |
6811 | kfree(topts); | |
6812 | return; | |
6813 | } | |
6814 | ||
6815 | tr->topts = tr_topts; | |
6816 | tr->topts[tr->nr_topts].tracer = tracer; | |
6817 | tr->topts[tr->nr_topts].topts = topts; | |
6818 | tr->nr_topts++; | |
577b785f | 6819 | |
41d9c0be | 6820 | for (cnt = 0; opts[cnt].name; cnt++) { |
2b6080f2 | 6821 | create_trace_option_file(tr, &topts[cnt], flags, |
577b785f | 6822 | &opts[cnt]); |
41d9c0be SRRH |
6823 | WARN_ONCE(topts[cnt].entry == NULL, |
6824 | "Failed to create trace option: %s", | |
6825 | opts[cnt].name); | |
6826 | } | |
577b785f SR |
6827 | } |
6828 | ||
a8259075 | 6829 | static struct dentry * |
2b6080f2 SR |
6830 | create_trace_option_core_file(struct trace_array *tr, |
6831 | const char *option, long index) | |
a8259075 SR |
6832 | { |
6833 | struct dentry *t_options; | |
a8259075 | 6834 | |
2b6080f2 | 6835 | t_options = trace_options_init_dentry(tr); |
a8259075 SR |
6836 | if (!t_options) |
6837 | return NULL; | |
6838 | ||
9a38a885 SRRH |
6839 | return trace_create_file(option, 0644, t_options, |
6840 | (void *)&tr->trace_flags_index[index], | |
6841 | &trace_options_core_fops); | |
a8259075 SR |
6842 | } |
6843 | ||
16270145 | 6844 | static void create_trace_options_dir(struct trace_array *tr) |
a8259075 SR |
6845 | { |
6846 | struct dentry *t_options; | |
16270145 | 6847 | bool top_level = tr == &global_trace; |
a8259075 SR |
6848 | int i; |
6849 | ||
2b6080f2 | 6850 | t_options = trace_options_init_dentry(tr); |
a8259075 SR |
6851 | if (!t_options) |
6852 | return; | |
6853 | ||
16270145 SRRH |
6854 | for (i = 0; trace_options[i]; i++) { |
6855 | if (top_level || | |
6856 | !((1 << i) & TOP_LEVEL_TRACE_FLAGS)) | |
6857 | create_trace_option_core_file(tr, trace_options[i], i); | |
6858 | } | |
a8259075 SR |
6859 | } |
6860 | ||
499e5470 SR |
6861 | static ssize_t |
6862 | rb_simple_read(struct file *filp, char __user *ubuf, | |
6863 | size_t cnt, loff_t *ppos) | |
6864 | { | |
348f0fc2 | 6865 | struct trace_array *tr = filp->private_data; |
499e5470 SR |
6866 | char buf[64]; |
6867 | int r; | |
6868 | ||
10246fa3 | 6869 | r = tracer_tracing_is_on(tr); |
499e5470 SR |
6870 | r = sprintf(buf, "%d\n", r); |
6871 | ||
6872 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
6873 | } | |
6874 | ||
6875 | static ssize_t | |
6876 | rb_simple_write(struct file *filp, const char __user *ubuf, | |
6877 | size_t cnt, loff_t *ppos) | |
6878 | { | |
348f0fc2 | 6879 | struct trace_array *tr = filp->private_data; |
12883efb | 6880 | struct ring_buffer *buffer = tr->trace_buffer.buffer; |
499e5470 SR |
6881 | unsigned long val; |
6882 | int ret; | |
6883 | ||
6884 | ret = kstrtoul_from_user(ubuf, cnt, 10, &val); | |
6885 | if (ret) | |
6886 | return ret; | |
6887 | ||
6888 | if (buffer) { | |
2df8f8a6 SR |
6889 | mutex_lock(&trace_types_lock); |
6890 | if (val) { | |
10246fa3 | 6891 | tracer_tracing_on(tr); |
2b6080f2 SR |
6892 | if (tr->current_trace->start) |
6893 | tr->current_trace->start(tr); | |
2df8f8a6 | 6894 | } else { |
10246fa3 | 6895 | tracer_tracing_off(tr); |
2b6080f2 SR |
6896 | if (tr->current_trace->stop) |
6897 | tr->current_trace->stop(tr); | |
2df8f8a6 SR |
6898 | } |
6899 | mutex_unlock(&trace_types_lock); | |
499e5470 SR |
6900 | } |
6901 | ||
6902 | (*ppos)++; | |
6903 | ||
6904 | return cnt; | |
6905 | } | |
6906 | ||
6907 | static const struct file_operations rb_simple_fops = { | |
7b85af63 | 6908 | .open = tracing_open_generic_tr, |
499e5470 SR |
6909 | .read = rb_simple_read, |
6910 | .write = rb_simple_write, | |
7b85af63 | 6911 | .release = tracing_release_generic_tr, |
499e5470 SR |
6912 | .llseek = default_llseek, |
6913 | }; | |
6914 | ||
277ba044 SR |
6915 | struct dentry *trace_instance_dir; |
6916 | ||
6917 | static void | |
8434dc93 | 6918 | init_tracer_tracefs(struct trace_array *tr, struct dentry *d_tracer); |
277ba044 | 6919 | |
55034cd6 SRRH |
6920 | static int |
6921 | allocate_trace_buffer(struct trace_array *tr, struct trace_buffer *buf, int size) | |
277ba044 SR |
6922 | { |
6923 | enum ring_buffer_flags rb_flags; | |
737223fb | 6924 | |
983f938a | 6925 | rb_flags = tr->trace_flags & TRACE_ITER_OVERWRITE ? RB_FL_OVERWRITE : 0; |
737223fb | 6926 | |
dced341b SRRH |
6927 | buf->tr = tr; |
6928 | ||
55034cd6 SRRH |
6929 | buf->buffer = ring_buffer_alloc(size, rb_flags); |
6930 | if (!buf->buffer) | |
6931 | return -ENOMEM; | |
737223fb | 6932 | |
55034cd6 SRRH |
6933 | buf->data = alloc_percpu(struct trace_array_cpu); |
6934 | if (!buf->data) { | |
6935 | ring_buffer_free(buf->buffer); | |
6936 | return -ENOMEM; | |
6937 | } | |
737223fb | 6938 | |
737223fb SRRH |
6939 | /* Allocate the first page for all buffers */ |
6940 | set_buffer_entries(&tr->trace_buffer, | |
6941 | ring_buffer_size(tr->trace_buffer.buffer, 0)); | |
6942 | ||
55034cd6 SRRH |
6943 | return 0; |
6944 | } | |
737223fb | 6945 | |
55034cd6 SRRH |
6946 | static int allocate_trace_buffers(struct trace_array *tr, int size) |
6947 | { | |
6948 | int ret; | |
737223fb | 6949 | |
55034cd6 SRRH |
6950 | ret = allocate_trace_buffer(tr, &tr->trace_buffer, size); |
6951 | if (ret) | |
6952 | return ret; | |
737223fb | 6953 | |
55034cd6 SRRH |
6954 | #ifdef CONFIG_TRACER_MAX_TRACE |
6955 | ret = allocate_trace_buffer(tr, &tr->max_buffer, | |
6956 | allocate_snapshot ? size : 1); | |
6957 | if (WARN_ON(ret)) { | |
737223fb | 6958 | ring_buffer_free(tr->trace_buffer.buffer); |
55034cd6 SRRH |
6959 | free_percpu(tr->trace_buffer.data); |
6960 | return -ENOMEM; | |
6961 | } | |
6962 | tr->allocated_snapshot = allocate_snapshot; | |
737223fb | 6963 | |
55034cd6 SRRH |
6964 | /* |
6965 | * Only the top level trace array gets its snapshot allocated | |
6966 | * from the kernel command line. | |
6967 | */ | |
6968 | allocate_snapshot = false; | |
737223fb | 6969 | #endif |
55034cd6 | 6970 | return 0; |
737223fb SRRH |
6971 | } |
6972 | ||
f0b70cc4 SRRH |
6973 | static void free_trace_buffer(struct trace_buffer *buf) |
6974 | { | |
6975 | if (buf->buffer) { | |
6976 | ring_buffer_free(buf->buffer); | |
6977 | buf->buffer = NULL; | |
6978 | free_percpu(buf->data); | |
6979 | buf->data = NULL; | |
6980 | } | |
6981 | } | |
6982 | ||
23aaa3c1 SRRH |
6983 | static void free_trace_buffers(struct trace_array *tr) |
6984 | { | |
6985 | if (!tr) | |
6986 | return; | |
6987 | ||
f0b70cc4 | 6988 | free_trace_buffer(&tr->trace_buffer); |
23aaa3c1 SRRH |
6989 | |
6990 | #ifdef CONFIG_TRACER_MAX_TRACE | |
f0b70cc4 | 6991 | free_trace_buffer(&tr->max_buffer); |
23aaa3c1 SRRH |
6992 | #endif |
6993 | } | |
6994 | ||
9a38a885 SRRH |
6995 | static void init_trace_flags_index(struct trace_array *tr) |
6996 | { | |
6997 | int i; | |
6998 | ||
6999 | /* Used by the trace options files */ | |
7000 | for (i = 0; i < TRACE_FLAGS_MAX_SIZE; i++) | |
7001 | tr->trace_flags_index[i] = i; | |
7002 | } | |
7003 | ||
37aea98b SRRH |
7004 | static void __update_tracer_options(struct trace_array *tr) |
7005 | { | |
7006 | struct tracer *t; | |
7007 | ||
7008 | for (t = trace_types; t; t = t->next) | |
7009 | add_tracer_options(tr, t); | |
7010 | } | |
7011 | ||
7012 | static void update_tracer_options(struct trace_array *tr) | |
7013 | { | |
7014 | mutex_lock(&trace_types_lock); | |
7015 | __update_tracer_options(tr); | |
7016 | mutex_unlock(&trace_types_lock); | |
7017 | } | |
7018 | ||
eae47358 | 7019 | static int instance_mkdir(const char *name) |
737223fb | 7020 | { |
277ba044 SR |
7021 | struct trace_array *tr; |
7022 | int ret; | |
277ba044 SR |
7023 | |
7024 | mutex_lock(&trace_types_lock); | |
7025 | ||
7026 | ret = -EEXIST; | |
7027 | list_for_each_entry(tr, &ftrace_trace_arrays, list) { | |
7028 | if (tr->name && strcmp(tr->name, name) == 0) | |
7029 | goto out_unlock; | |
7030 | } | |
7031 | ||
7032 | ret = -ENOMEM; | |
7033 | tr = kzalloc(sizeof(*tr), GFP_KERNEL); | |
7034 | if (!tr) | |
7035 | goto out_unlock; | |
7036 | ||
7037 | tr->name = kstrdup(name, GFP_KERNEL); | |
7038 | if (!tr->name) | |
7039 | goto out_free_tr; | |
7040 | ||
ccfe9e42 AL |
7041 | if (!alloc_cpumask_var(&tr->tracing_cpumask, GFP_KERNEL)) |
7042 | goto out_free_tr; | |
7043 | ||
20550622 | 7044 | tr->trace_flags = global_trace.trace_flags & ~ZEROED_TRACE_FLAGS; |
983f938a | 7045 | |
ccfe9e42 AL |
7046 | cpumask_copy(tr->tracing_cpumask, cpu_all_mask); |
7047 | ||
277ba044 SR |
7048 | raw_spin_lock_init(&tr->start_lock); |
7049 | ||
0b9b12c1 SRRH |
7050 | tr->max_lock = (arch_spinlock_t)__ARCH_SPIN_LOCK_UNLOCKED; |
7051 | ||
277ba044 SR |
7052 | tr->current_trace = &nop_trace; |
7053 | ||
7054 | INIT_LIST_HEAD(&tr->systems); | |
7055 | INIT_LIST_HEAD(&tr->events); | |
7056 | ||
737223fb | 7057 | if (allocate_trace_buffers(tr, trace_buf_size) < 0) |
277ba044 SR |
7058 | goto out_free_tr; |
7059 | ||
8434dc93 | 7060 | tr->dir = tracefs_create_dir(name, trace_instance_dir); |
277ba044 SR |
7061 | if (!tr->dir) |
7062 | goto out_free_tr; | |
7063 | ||
7064 | ret = event_trace_add_tracer(tr->dir, tr); | |
609e85a7 | 7065 | if (ret) { |
8434dc93 | 7066 | tracefs_remove_recursive(tr->dir); |
277ba044 | 7067 | goto out_free_tr; |
609e85a7 | 7068 | } |
277ba044 | 7069 | |
8434dc93 | 7070 | init_tracer_tracefs(tr, tr->dir); |
9a38a885 | 7071 | init_trace_flags_index(tr); |
37aea98b | 7072 | __update_tracer_options(tr); |
277ba044 SR |
7073 | |
7074 | list_add(&tr->list, &ftrace_trace_arrays); | |
7075 | ||
7076 | mutex_unlock(&trace_types_lock); | |
7077 | ||
7078 | return 0; | |
7079 | ||
7080 | out_free_tr: | |
23aaa3c1 | 7081 | free_trace_buffers(tr); |
ccfe9e42 | 7082 | free_cpumask_var(tr->tracing_cpumask); |
277ba044 SR |
7083 | kfree(tr->name); |
7084 | kfree(tr); | |
7085 | ||
7086 | out_unlock: | |
7087 | mutex_unlock(&trace_types_lock); | |
7088 | ||
7089 | return ret; | |
7090 | ||
7091 | } | |
7092 | ||
eae47358 | 7093 | static int instance_rmdir(const char *name) |
0c8916c3 SR |
7094 | { |
7095 | struct trace_array *tr; | |
7096 | int found = 0; | |
7097 | int ret; | |
37aea98b | 7098 | int i; |
0c8916c3 SR |
7099 | |
7100 | mutex_lock(&trace_types_lock); | |
7101 | ||
7102 | ret = -ENODEV; | |
7103 | list_for_each_entry(tr, &ftrace_trace_arrays, list) { | |
7104 | if (tr->name && strcmp(tr->name, name) == 0) { | |
7105 | found = 1; | |
7106 | break; | |
7107 | } | |
7108 | } | |
7109 | if (!found) | |
7110 | goto out_unlock; | |
7111 | ||
a695cb58 | 7112 | ret = -EBUSY; |
cf6ab6d9 | 7113 | if (tr->ref || (tr->current_trace && tr->current_trace->ref)) |
a695cb58 SRRH |
7114 | goto out_unlock; |
7115 | ||
0c8916c3 SR |
7116 | list_del(&tr->list); |
7117 | ||
20550622 SRRH |
7118 | /* Disable all the flags that were enabled coming in */ |
7119 | for (i = 0; i < TRACE_FLAGS_MAX_SIZE; i++) { | |
7120 | if ((1 << i) & ZEROED_TRACE_FLAGS) | |
7121 | set_tracer_flag(tr, 1 << i, 0); | |
7122 | } | |
7123 | ||
6b450d25 | 7124 | tracing_set_nop(tr); |
0c8916c3 | 7125 | event_trace_del_tracer(tr); |
591dffda | 7126 | ftrace_destroy_function_files(tr); |
681a4a2f | 7127 | tracefs_remove_recursive(tr->dir); |
a9fcaaac | 7128 | free_trace_buffers(tr); |
0c8916c3 | 7129 | |
37aea98b SRRH |
7130 | for (i = 0; i < tr->nr_topts; i++) { |
7131 | kfree(tr->topts[i].topts); | |
7132 | } | |
7133 | kfree(tr->topts); | |
7134 | ||
0c8916c3 SR |
7135 | kfree(tr->name); |
7136 | kfree(tr); | |
7137 | ||
7138 | ret = 0; | |
7139 | ||
7140 | out_unlock: | |
7141 | mutex_unlock(&trace_types_lock); | |
7142 | ||
7143 | return ret; | |
7144 | } | |
7145 | ||
277ba044 SR |
7146 | static __init void create_trace_instances(struct dentry *d_tracer) |
7147 | { | |
eae47358 SRRH |
7148 | trace_instance_dir = tracefs_create_instance_dir("instances", d_tracer, |
7149 | instance_mkdir, | |
7150 | instance_rmdir); | |
277ba044 SR |
7151 | if (WARN_ON(!trace_instance_dir)) |
7152 | return; | |
277ba044 SR |
7153 | } |
7154 | ||
2b6080f2 | 7155 | static void |
8434dc93 | 7156 | init_tracer_tracefs(struct trace_array *tr, struct dentry *d_tracer) |
2b6080f2 | 7157 | { |
121aaee7 | 7158 | int cpu; |
2b6080f2 | 7159 | |
607e2ea1 SRRH |
7160 | trace_create_file("available_tracers", 0444, d_tracer, |
7161 | tr, &show_traces_fops); | |
7162 | ||
7163 | trace_create_file("current_tracer", 0644, d_tracer, | |
7164 | tr, &set_tracer_fops); | |
7165 | ||
ccfe9e42 AL |
7166 | trace_create_file("tracing_cpumask", 0644, d_tracer, |
7167 | tr, &tracing_cpumask_fops); | |
7168 | ||
2b6080f2 SR |
7169 | trace_create_file("trace_options", 0644, d_tracer, |
7170 | tr, &tracing_iter_fops); | |
7171 | ||
7172 | trace_create_file("trace", 0644, d_tracer, | |
6484c71c | 7173 | tr, &tracing_fops); |
2b6080f2 SR |
7174 | |
7175 | trace_create_file("trace_pipe", 0444, d_tracer, | |
15544209 | 7176 | tr, &tracing_pipe_fops); |
2b6080f2 SR |
7177 | |
7178 | trace_create_file("buffer_size_kb", 0644, d_tracer, | |
0bc392ee | 7179 | tr, &tracing_entries_fops); |
2b6080f2 SR |
7180 | |
7181 | trace_create_file("buffer_total_size_kb", 0444, d_tracer, | |
7182 | tr, &tracing_total_entries_fops); | |
7183 | ||
238ae93d | 7184 | trace_create_file("free_buffer", 0200, d_tracer, |
2b6080f2 SR |
7185 | tr, &tracing_free_buffer_fops); |
7186 | ||
7187 | trace_create_file("trace_marker", 0220, d_tracer, | |
7188 | tr, &tracing_mark_fops); | |
7189 | ||
7190 | trace_create_file("trace_clock", 0644, d_tracer, tr, | |
7191 | &trace_clock_fops); | |
7192 | ||
7193 | trace_create_file("tracing_on", 0644, d_tracer, | |
6484c71c | 7194 | tr, &rb_simple_fops); |
ce9bae55 | 7195 | |
16270145 SRRH |
7196 | create_trace_options_dir(tr); |
7197 | ||
6d9b3fa5 SRRH |
7198 | #ifdef CONFIG_TRACER_MAX_TRACE |
7199 | trace_create_file("tracing_max_latency", 0644, d_tracer, | |
7200 | &tr->max_latency, &tracing_max_lat_fops); | |
7201 | #endif | |
7202 | ||
591dffda SRRH |
7203 | if (ftrace_create_function_files(tr, d_tracer)) |
7204 | WARN(1, "Could not allocate function filter files"); | |
7205 | ||
ce9bae55 SRRH |
7206 | #ifdef CONFIG_TRACER_SNAPSHOT |
7207 | trace_create_file("snapshot", 0644, d_tracer, | |
6484c71c | 7208 | tr, &snapshot_fops); |
ce9bae55 | 7209 | #endif |
121aaee7 SRRH |
7210 | |
7211 | for_each_tracing_cpu(cpu) | |
8434dc93 | 7212 | tracing_init_tracefs_percpu(tr, cpu); |
121aaee7 | 7213 | |
345ddcc8 | 7214 | ftrace_init_tracefs(tr, d_tracer); |
2b6080f2 SR |
7215 | } |
7216 | ||
f76180bc SRRH |
7217 | static struct vfsmount *trace_automount(void *ingore) |
7218 | { | |
7219 | struct vfsmount *mnt; | |
7220 | struct file_system_type *type; | |
7221 | ||
7222 | /* | |
7223 | * To maintain backward compatibility for tools that mount | |
7224 | * debugfs to get to the tracing facility, tracefs is automatically | |
7225 | * mounted to the debugfs/tracing directory. | |
7226 | */ | |
7227 | type = get_fs_type("tracefs"); | |
7228 | if (!type) | |
7229 | return NULL; | |
7230 | mnt = vfs_kern_mount(type, 0, "tracefs", NULL); | |
7231 | put_filesystem(type); | |
7232 | if (IS_ERR(mnt)) | |
7233 | return NULL; | |
7234 | mntget(mnt); | |
7235 | ||
7236 | return mnt; | |
7237 | } | |
7238 | ||
7eeafbca SRRH |
7239 | /** |
7240 | * tracing_init_dentry - initialize top level trace array | |
7241 | * | |
7242 | * This is called when creating files or directories in the tracing | |
7243 | * directory. It is called via fs_initcall() by any of the boot up code | |
7244 | * and expects to return the dentry of the top level tracing directory. | |
7245 | */ | |
7246 | struct dentry *tracing_init_dentry(void) | |
7247 | { | |
7248 | struct trace_array *tr = &global_trace; | |
7249 | ||
f76180bc | 7250 | /* The top level trace array uses NULL as parent */ |
7eeafbca | 7251 | if (tr->dir) |
f76180bc | 7252 | return NULL; |
7eeafbca | 7253 | |
8b129199 JW |
7254 | if (WARN_ON(!tracefs_initialized()) || |
7255 | (IS_ENABLED(CONFIG_DEBUG_FS) && | |
7256 | WARN_ON(!debugfs_initialized()))) | |
7eeafbca SRRH |
7257 | return ERR_PTR(-ENODEV); |
7258 | ||
f76180bc SRRH |
7259 | /* |
7260 | * As there may still be users that expect the tracing | |
7261 | * files to exist in debugfs/tracing, we must automount | |
7262 | * the tracefs file system there, so older tools still | |
7263 | * work with the newer kerenl. | |
7264 | */ | |
7265 | tr->dir = debugfs_create_automount("tracing", NULL, | |
7266 | trace_automount, NULL); | |
7eeafbca SRRH |
7267 | if (!tr->dir) { |
7268 | pr_warn_once("Could not create debugfs directory 'tracing'\n"); | |
7269 | return ERR_PTR(-ENOMEM); | |
7270 | } | |
7271 | ||
8434dc93 | 7272 | return NULL; |
7eeafbca SRRH |
7273 | } |
7274 | ||
0c564a53 SRRH |
7275 | extern struct trace_enum_map *__start_ftrace_enum_maps[]; |
7276 | extern struct trace_enum_map *__stop_ftrace_enum_maps[]; | |
7277 | ||
7278 | static void __init trace_enum_init(void) | |
7279 | { | |
3673b8e4 SRRH |
7280 | int len; |
7281 | ||
7282 | len = __stop_ftrace_enum_maps - __start_ftrace_enum_maps; | |
9828413d | 7283 | trace_insert_enum_map(NULL, __start_ftrace_enum_maps, len); |
3673b8e4 SRRH |
7284 | } |
7285 | ||
7286 | #ifdef CONFIG_MODULES | |
7287 | static void trace_module_add_enums(struct module *mod) | |
7288 | { | |
7289 | if (!mod->num_trace_enums) | |
7290 | return; | |
7291 | ||
7292 | /* | |
7293 | * Modules with bad taint do not have events created, do | |
7294 | * not bother with enums either. | |
7295 | */ | |
7296 | if (trace_module_has_bad_taint(mod)) | |
7297 | return; | |
7298 | ||
9828413d | 7299 | trace_insert_enum_map(mod, mod->trace_enums, mod->num_trace_enums); |
3673b8e4 SRRH |
7300 | } |
7301 | ||
9828413d SRRH |
7302 | #ifdef CONFIG_TRACE_ENUM_MAP_FILE |
7303 | static void trace_module_remove_enums(struct module *mod) | |
7304 | { | |
7305 | union trace_enum_map_item *map; | |
7306 | union trace_enum_map_item **last = &trace_enum_maps; | |
7307 | ||
7308 | if (!mod->num_trace_enums) | |
7309 | return; | |
7310 | ||
7311 | mutex_lock(&trace_enum_mutex); | |
7312 | ||
7313 | map = trace_enum_maps; | |
7314 | ||
7315 | while (map) { | |
7316 | if (map->head.mod == mod) | |
7317 | break; | |
7318 | map = trace_enum_jmp_to_tail(map); | |
7319 | last = &map->tail.next; | |
7320 | map = map->tail.next; | |
7321 | } | |
7322 | if (!map) | |
7323 | goto out; | |
7324 | ||
7325 | *last = trace_enum_jmp_to_tail(map)->tail.next; | |
7326 | kfree(map); | |
7327 | out: | |
7328 | mutex_unlock(&trace_enum_mutex); | |
7329 | } | |
7330 | #else | |
7331 | static inline void trace_module_remove_enums(struct module *mod) { } | |
7332 | #endif /* CONFIG_TRACE_ENUM_MAP_FILE */ | |
7333 | ||
3673b8e4 SRRH |
7334 | static int trace_module_notify(struct notifier_block *self, |
7335 | unsigned long val, void *data) | |
7336 | { | |
7337 | struct module *mod = data; | |
7338 | ||
7339 | switch (val) { | |
7340 | case MODULE_STATE_COMING: | |
7341 | trace_module_add_enums(mod); | |
7342 | break; | |
9828413d SRRH |
7343 | case MODULE_STATE_GOING: |
7344 | trace_module_remove_enums(mod); | |
7345 | break; | |
3673b8e4 SRRH |
7346 | } |
7347 | ||
7348 | return 0; | |
0c564a53 SRRH |
7349 | } |
7350 | ||
3673b8e4 SRRH |
7351 | static struct notifier_block trace_module_nb = { |
7352 | .notifier_call = trace_module_notify, | |
7353 | .priority = 0, | |
7354 | }; | |
9828413d | 7355 | #endif /* CONFIG_MODULES */ |
3673b8e4 | 7356 | |
8434dc93 | 7357 | static __init int tracer_init_tracefs(void) |
bc0c38d1 SR |
7358 | { |
7359 | struct dentry *d_tracer; | |
bc0c38d1 | 7360 | |
7e53bd42 LJ |
7361 | trace_access_lock_init(); |
7362 | ||
bc0c38d1 | 7363 | d_tracer = tracing_init_dentry(); |
14a5ae40 | 7364 | if (IS_ERR(d_tracer)) |
ed6f1c99 | 7365 | return 0; |
bc0c38d1 | 7366 | |
8434dc93 | 7367 | init_tracer_tracefs(&global_trace, d_tracer); |
501c2375 | 7368 | ftrace_init_tracefs_toplevel(&global_trace, d_tracer); |
bc0c38d1 | 7369 | |
5452af66 | 7370 | trace_create_file("tracing_thresh", 0644, d_tracer, |
6508fa76 | 7371 | &global_trace, &tracing_thresh_fops); |
a8259075 | 7372 | |
339ae5d3 | 7373 | trace_create_file("README", 0444, d_tracer, |
5452af66 FW |
7374 | NULL, &tracing_readme_fops); |
7375 | ||
69abe6a5 AP |
7376 | trace_create_file("saved_cmdlines", 0444, d_tracer, |
7377 | NULL, &tracing_saved_cmdlines_fops); | |
5bf9a1ee | 7378 | |
939c7a4f YY |
7379 | trace_create_file("saved_cmdlines_size", 0644, d_tracer, |
7380 | NULL, &tracing_saved_cmdlines_size_fops); | |
7381 | ||
0c564a53 SRRH |
7382 | trace_enum_init(); |
7383 | ||
9828413d SRRH |
7384 | trace_create_enum_file(d_tracer); |
7385 | ||
3673b8e4 SRRH |
7386 | #ifdef CONFIG_MODULES |
7387 | register_module_notifier(&trace_module_nb); | |
7388 | #endif | |
7389 | ||
bc0c38d1 | 7390 | #ifdef CONFIG_DYNAMIC_FTRACE |
5452af66 FW |
7391 | trace_create_file("dyn_ftrace_total_info", 0444, d_tracer, |
7392 | &ftrace_update_tot_cnt, &tracing_dyn_info_fops); | |
bc0c38d1 | 7393 | #endif |
b04cc6b1 | 7394 | |
277ba044 | 7395 | create_trace_instances(d_tracer); |
5452af66 | 7396 | |
37aea98b | 7397 | update_tracer_options(&global_trace); |
09d23a1d | 7398 | |
b5ad384e | 7399 | return 0; |
bc0c38d1 SR |
7400 | } |
7401 | ||
3f5a54e3 SR |
7402 | static int trace_panic_handler(struct notifier_block *this, |
7403 | unsigned long event, void *unused) | |
7404 | { | |
944ac425 | 7405 | if (ftrace_dump_on_oops) |
cecbca96 | 7406 | ftrace_dump(ftrace_dump_on_oops); |
3f5a54e3 SR |
7407 | return NOTIFY_OK; |
7408 | } | |
7409 | ||
7410 | static struct notifier_block trace_panic_notifier = { | |
7411 | .notifier_call = trace_panic_handler, | |
7412 | .next = NULL, | |
7413 | .priority = 150 /* priority: INT_MAX >= x >= 0 */ | |
7414 | }; | |
7415 | ||
7416 | static int trace_die_handler(struct notifier_block *self, | |
7417 | unsigned long val, | |
7418 | void *data) | |
7419 | { | |
7420 | switch (val) { | |
7421 | case DIE_OOPS: | |
944ac425 | 7422 | if (ftrace_dump_on_oops) |
cecbca96 | 7423 | ftrace_dump(ftrace_dump_on_oops); |
3f5a54e3 SR |
7424 | break; |
7425 | default: | |
7426 | break; | |
7427 | } | |
7428 | return NOTIFY_OK; | |
7429 | } | |
7430 | ||
7431 | static struct notifier_block trace_die_notifier = { | |
7432 | .notifier_call = trace_die_handler, | |
7433 | .priority = 200 | |
7434 | }; | |
7435 | ||
7436 | /* | |
7437 | * printk is set to max of 1024, we really don't need it that big. | |
7438 | * Nothing should be printing 1000 characters anyway. | |
7439 | */ | |
7440 | #define TRACE_MAX_PRINT 1000 | |
7441 | ||
7442 | /* | |
7443 | * Define here KERN_TRACE so that we have one place to modify | |
7444 | * it if we decide to change what log level the ftrace dump | |
7445 | * should be at. | |
7446 | */ | |
428aee14 | 7447 | #define KERN_TRACE KERN_EMERG |
3f5a54e3 | 7448 | |
955b61e5 | 7449 | void |
3f5a54e3 SR |
7450 | trace_printk_seq(struct trace_seq *s) |
7451 | { | |
7452 | /* Probably should print a warning here. */ | |
3a161d99 SRRH |
7453 | if (s->seq.len >= TRACE_MAX_PRINT) |
7454 | s->seq.len = TRACE_MAX_PRINT; | |
3f5a54e3 | 7455 | |
820b75f6 SRRH |
7456 | /* |
7457 | * More paranoid code. Although the buffer size is set to | |
7458 | * PAGE_SIZE, and TRACE_MAX_PRINT is 1000, this is just | |
7459 | * an extra layer of protection. | |
7460 | */ | |
7461 | if (WARN_ON_ONCE(s->seq.len >= s->seq.size)) | |
7462 | s->seq.len = s->seq.size - 1; | |
3f5a54e3 SR |
7463 | |
7464 | /* should be zero ended, but we are paranoid. */ | |
3a161d99 | 7465 | s->buffer[s->seq.len] = 0; |
3f5a54e3 SR |
7466 | |
7467 | printk(KERN_TRACE "%s", s->buffer); | |
7468 | ||
f9520750 | 7469 | trace_seq_init(s); |
3f5a54e3 SR |
7470 | } |
7471 | ||
955b61e5 JW |
7472 | void trace_init_global_iter(struct trace_iterator *iter) |
7473 | { | |
7474 | iter->tr = &global_trace; | |
2b6080f2 | 7475 | iter->trace = iter->tr->current_trace; |
ae3b5093 | 7476 | iter->cpu_file = RING_BUFFER_ALL_CPUS; |
12883efb | 7477 | iter->trace_buffer = &global_trace.trace_buffer; |
b2f974d6 CS |
7478 | |
7479 | if (iter->trace && iter->trace->open) | |
7480 | iter->trace->open(iter); | |
7481 | ||
7482 | /* Annotate start of buffers if we had overruns */ | |
7483 | if (ring_buffer_overruns(iter->trace_buffer->buffer)) | |
7484 | iter->iter_flags |= TRACE_FILE_ANNOTATE; | |
7485 | ||
7486 | /* Output in nanoseconds only if we are using a clock in nanoseconds. */ | |
7487 | if (trace_clocks[iter->tr->clock_id].in_ns) | |
7488 | iter->iter_flags |= TRACE_FILE_TIME_IN_NS; | |
955b61e5 JW |
7489 | } |
7490 | ||
7fe70b57 | 7491 | void ftrace_dump(enum ftrace_dump_mode oops_dump_mode) |
3f5a54e3 | 7492 | { |
3f5a54e3 SR |
7493 | /* use static because iter can be a bit big for the stack */ |
7494 | static struct trace_iterator iter; | |
7fe70b57 | 7495 | static atomic_t dump_running; |
983f938a | 7496 | struct trace_array *tr = &global_trace; |
cf586b61 | 7497 | unsigned int old_userobj; |
d769041f SR |
7498 | unsigned long flags; |
7499 | int cnt = 0, cpu; | |
3f5a54e3 | 7500 | |
7fe70b57 SRRH |
7501 | /* Only allow one dump user at a time. */ |
7502 | if (atomic_inc_return(&dump_running) != 1) { | |
7503 | atomic_dec(&dump_running); | |
7504 | return; | |
7505 | } | |
3f5a54e3 | 7506 | |
7fe70b57 SRRH |
7507 | /* |
7508 | * Always turn off tracing when we dump. | |
7509 | * We don't need to show trace output of what happens | |
7510 | * between multiple crashes. | |
7511 | * | |
7512 | * If the user does a sysrq-z, then they can re-enable | |
7513 | * tracing with echo 1 > tracing_on. | |
7514 | */ | |
0ee6b6cf | 7515 | tracing_off(); |
cf586b61 | 7516 | |
7fe70b57 | 7517 | local_irq_save(flags); |
3f5a54e3 | 7518 | |
38dbe0b1 | 7519 | /* Simulate the iterator */ |
955b61e5 JW |
7520 | trace_init_global_iter(&iter); |
7521 | ||
d769041f | 7522 | for_each_tracing_cpu(cpu) { |
5e2d5ef8 | 7523 | atomic_inc(&per_cpu_ptr(iter.trace_buffer->data, cpu)->disabled); |
d769041f SR |
7524 | } |
7525 | ||
983f938a | 7526 | old_userobj = tr->trace_flags & TRACE_ITER_SYM_USEROBJ; |
cf586b61 | 7527 | |
b54d3de9 | 7528 | /* don't look at user memory in panic mode */ |
983f938a | 7529 | tr->trace_flags &= ~TRACE_ITER_SYM_USEROBJ; |
b54d3de9 | 7530 | |
cecbca96 FW |
7531 | switch (oops_dump_mode) { |
7532 | case DUMP_ALL: | |
ae3b5093 | 7533 | iter.cpu_file = RING_BUFFER_ALL_CPUS; |
cecbca96 FW |
7534 | break; |
7535 | case DUMP_ORIG: | |
7536 | iter.cpu_file = raw_smp_processor_id(); | |
7537 | break; | |
7538 | case DUMP_NONE: | |
7539 | goto out_enable; | |
7540 | default: | |
7541 | printk(KERN_TRACE "Bad dumping mode, switching to all CPUs dump\n"); | |
ae3b5093 | 7542 | iter.cpu_file = RING_BUFFER_ALL_CPUS; |
cecbca96 FW |
7543 | } |
7544 | ||
7545 | printk(KERN_TRACE "Dumping ftrace buffer:\n"); | |
3f5a54e3 | 7546 | |
7fe70b57 SRRH |
7547 | /* Did function tracer already get disabled? */ |
7548 | if (ftrace_is_dead()) { | |
7549 | printk("# WARNING: FUNCTION TRACING IS CORRUPTED\n"); | |
7550 | printk("# MAY BE MISSING FUNCTION EVENTS\n"); | |
7551 | } | |
7552 | ||
3f5a54e3 SR |
7553 | /* |
7554 | * We need to stop all tracing on all CPUS to read the | |
7555 | * the next buffer. This is a bit expensive, but is | |
7556 | * not done often. We fill all what we can read, | |
7557 | * and then release the locks again. | |
7558 | */ | |
7559 | ||
3f5a54e3 SR |
7560 | while (!trace_empty(&iter)) { |
7561 | ||
7562 | if (!cnt) | |
7563 | printk(KERN_TRACE "---------------------------------\n"); | |
7564 | ||
7565 | cnt++; | |
7566 | ||
7567 | /* reset all but tr, trace, and overruns */ | |
7568 | memset(&iter.seq, 0, | |
7569 | sizeof(struct trace_iterator) - | |
7570 | offsetof(struct trace_iterator, seq)); | |
7571 | iter.iter_flags |= TRACE_FILE_LAT_FMT; | |
7572 | iter.pos = -1; | |
7573 | ||
955b61e5 | 7574 | if (trace_find_next_entry_inc(&iter) != NULL) { |
74e7ff8c LJ |
7575 | int ret; |
7576 | ||
7577 | ret = print_trace_line(&iter); | |
7578 | if (ret != TRACE_TYPE_NO_CONSUME) | |
7579 | trace_consume(&iter); | |
3f5a54e3 | 7580 | } |
b892e5c8 | 7581 | touch_nmi_watchdog(); |
3f5a54e3 SR |
7582 | |
7583 | trace_printk_seq(&iter.seq); | |
7584 | } | |
7585 | ||
7586 | if (!cnt) | |
7587 | printk(KERN_TRACE " (ftrace buffer empty)\n"); | |
7588 | else | |
7589 | printk(KERN_TRACE "---------------------------------\n"); | |
7590 | ||
cecbca96 | 7591 | out_enable: |
983f938a | 7592 | tr->trace_flags |= old_userobj; |
cf586b61 | 7593 | |
7fe70b57 SRRH |
7594 | for_each_tracing_cpu(cpu) { |
7595 | atomic_dec(&per_cpu_ptr(iter.trace_buffer->data, cpu)->disabled); | |
cf586b61 | 7596 | } |
7fe70b57 | 7597 | atomic_dec(&dump_running); |
cd891ae0 | 7598 | local_irq_restore(flags); |
3f5a54e3 | 7599 | } |
a8eecf22 | 7600 | EXPORT_SYMBOL_GPL(ftrace_dump); |
cf586b61 | 7601 | |
3928a8a2 | 7602 | __init static int tracer_alloc_buffers(void) |
bc0c38d1 | 7603 | { |
73c5162a | 7604 | int ring_buf_size; |
9e01c1b7 | 7605 | int ret = -ENOMEM; |
4c11d7ae | 7606 | |
b5e87c05 SRRH |
7607 | /* |
7608 | * Make sure we don't accidently add more trace options | |
7609 | * than we have bits for. | |
7610 | */ | |
9a38a885 | 7611 | BUILD_BUG_ON(TRACE_ITER_LAST_BIT > TRACE_FLAGS_MAX_SIZE); |
b5e87c05 | 7612 | |
9e01c1b7 RR |
7613 | if (!alloc_cpumask_var(&tracing_buffer_mask, GFP_KERNEL)) |
7614 | goto out; | |
7615 | ||
ccfe9e42 | 7616 | if (!alloc_cpumask_var(&global_trace.tracing_cpumask, GFP_KERNEL)) |
9e01c1b7 | 7617 | goto out_free_buffer_mask; |
4c11d7ae | 7618 | |
07d777fe SR |
7619 | /* Only allocate trace_printk buffers if a trace_printk exists */ |
7620 | if (__stop___trace_bprintk_fmt != __start___trace_bprintk_fmt) | |
81698831 | 7621 | /* Must be called before global_trace.buffer is allocated */ |
07d777fe SR |
7622 | trace_printk_init_buffers(); |
7623 | ||
73c5162a SR |
7624 | /* To save memory, keep the ring buffer size to its minimum */ |
7625 | if (ring_buffer_expanded) | |
7626 | ring_buf_size = trace_buf_size; | |
7627 | else | |
7628 | ring_buf_size = 1; | |
7629 | ||
9e01c1b7 | 7630 | cpumask_copy(tracing_buffer_mask, cpu_possible_mask); |
ccfe9e42 | 7631 | cpumask_copy(global_trace.tracing_cpumask, cpu_all_mask); |
9e01c1b7 | 7632 | |
2b6080f2 SR |
7633 | raw_spin_lock_init(&global_trace.start_lock); |
7634 | ||
2c4a33ab SRRH |
7635 | /* Used for event triggers */ |
7636 | temp_buffer = ring_buffer_alloc(PAGE_SIZE, RB_FL_OVERWRITE); | |
7637 | if (!temp_buffer) | |
7638 | goto out_free_cpumask; | |
7639 | ||
939c7a4f YY |
7640 | if (trace_create_savedcmd() < 0) |
7641 | goto out_free_temp_buffer; | |
7642 | ||
9e01c1b7 | 7643 | /* TODO: make the number of buffers hot pluggable with CPUS */ |
737223fb | 7644 | if (allocate_trace_buffers(&global_trace, ring_buf_size) < 0) { |
3928a8a2 SR |
7645 | printk(KERN_ERR "tracer: failed to allocate ring buffer!\n"); |
7646 | WARN_ON(1); | |
939c7a4f | 7647 | goto out_free_savedcmd; |
4c11d7ae | 7648 | } |
a7603ff4 | 7649 | |
499e5470 SR |
7650 | if (global_trace.buffer_disabled) |
7651 | tracing_off(); | |
4c11d7ae | 7652 | |
e1e232ca SR |
7653 | if (trace_boot_clock) { |
7654 | ret = tracing_set_clock(&global_trace, trace_boot_clock); | |
7655 | if (ret < 0) | |
a395d6a7 JP |
7656 | pr_warn("Trace clock %s not defined, going back to default\n", |
7657 | trace_boot_clock); | |
e1e232ca SR |
7658 | } |
7659 | ||
ca164318 SRRH |
7660 | /* |
7661 | * register_tracer() might reference current_trace, so it | |
7662 | * needs to be set before we register anything. This is | |
7663 | * just a bootstrap of current_trace anyway. | |
7664 | */ | |
2b6080f2 SR |
7665 | global_trace.current_trace = &nop_trace; |
7666 | ||
0b9b12c1 SRRH |
7667 | global_trace.max_lock = (arch_spinlock_t)__ARCH_SPIN_LOCK_UNLOCKED; |
7668 | ||
4104d326 SRRH |
7669 | ftrace_init_global_array_ops(&global_trace); |
7670 | ||
9a38a885 SRRH |
7671 | init_trace_flags_index(&global_trace); |
7672 | ||
ca164318 SRRH |
7673 | register_tracer(&nop_trace); |
7674 | ||
60a11774 SR |
7675 | /* All seems OK, enable tracing */ |
7676 | tracing_disabled = 0; | |
3928a8a2 | 7677 | |
3f5a54e3 SR |
7678 | atomic_notifier_chain_register(&panic_notifier_list, |
7679 | &trace_panic_notifier); | |
7680 | ||
7681 | register_die_notifier(&trace_die_notifier); | |
2fc1dfbe | 7682 | |
ae63b31e SR |
7683 | global_trace.flags = TRACE_ARRAY_FL_GLOBAL; |
7684 | ||
7685 | INIT_LIST_HEAD(&global_trace.systems); | |
7686 | INIT_LIST_HEAD(&global_trace.events); | |
7687 | list_add(&global_trace.list, &ftrace_trace_arrays); | |
7688 | ||
a4d1e688 | 7689 | apply_trace_boot_options(); |
7bcfaf54 | 7690 | |
77fd5c15 SRRH |
7691 | register_snapshot_cmd(); |
7692 | ||
2fc1dfbe | 7693 | return 0; |
3f5a54e3 | 7694 | |
939c7a4f YY |
7695 | out_free_savedcmd: |
7696 | free_saved_cmdlines_buffer(savedcmd); | |
2c4a33ab SRRH |
7697 | out_free_temp_buffer: |
7698 | ring_buffer_free(temp_buffer); | |
9e01c1b7 | 7699 | out_free_cpumask: |
ccfe9e42 | 7700 | free_cpumask_var(global_trace.tracing_cpumask); |
9e01c1b7 RR |
7701 | out_free_buffer_mask: |
7702 | free_cpumask_var(tracing_buffer_mask); | |
7703 | out: | |
7704 | return ret; | |
bc0c38d1 | 7705 | } |
b2821ae6 | 7706 | |
5f893b26 SRRH |
7707 | void __init trace_init(void) |
7708 | { | |
0daa2302 SRRH |
7709 | if (tracepoint_printk) { |
7710 | tracepoint_print_iter = | |
7711 | kmalloc(sizeof(*tracepoint_print_iter), GFP_KERNEL); | |
7712 | if (WARN_ON(!tracepoint_print_iter)) | |
7713 | tracepoint_printk = 0; | |
7714 | } | |
5f893b26 | 7715 | tracer_alloc_buffers(); |
0c564a53 | 7716 | trace_event_init(); |
5f893b26 SRRH |
7717 | } |
7718 | ||
b2821ae6 SR |
7719 | __init static int clear_boot_tracer(void) |
7720 | { | |
7721 | /* | |
7722 | * The default tracer at boot buffer is an init section. | |
7723 | * This function is called in lateinit. If we did not | |
7724 | * find the boot tracer, then clear it out, to prevent | |
7725 | * later registration from accessing the buffer that is | |
7726 | * about to be freed. | |
7727 | */ | |
7728 | if (!default_bootup_tracer) | |
7729 | return 0; | |
7730 | ||
7731 | printk(KERN_INFO "ftrace bootup tracer '%s' not registered.\n", | |
7732 | default_bootup_tracer); | |
7733 | default_bootup_tracer = NULL; | |
7734 | ||
7735 | return 0; | |
7736 | } | |
7737 | ||
8434dc93 | 7738 | fs_initcall(tracer_init_tracefs); |
b2821ae6 | 7739 | late_initcall(clear_boot_tracer); |