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Commit | Line | Data |
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bc0c38d1 SR |
1 | /* |
2 | * ring buffer based function tracer | |
3 | * | |
4 | * Copyright (C) 2007-2008 Steven Rostedt <srostedt@redhat.com> | |
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 | |
12 | * Copyright (C) 2004 William Lee Irwin III | |
13 | */ | |
14 | #include <linux/utsrelease.h> | |
15 | #include <linux/kallsyms.h> | |
16 | #include <linux/seq_file.h> | |
17 | #include <linux/debugfs.h> | |
4c11d7ae | 18 | #include <linux/pagemap.h> |
bc0c38d1 SR |
19 | #include <linux/hardirq.h> |
20 | #include <linux/linkage.h> | |
21 | #include <linux/uaccess.h> | |
22 | #include <linux/ftrace.h> | |
23 | #include <linux/module.h> | |
24 | #include <linux/percpu.h> | |
25 | #include <linux/ctype.h> | |
26 | #include <linux/init.h> | |
27 | #include <linux/gfp.h> | |
28 | #include <linux/fs.h> | |
29 | ||
30 | #include "trace.h" | |
31 | ||
32 | unsigned long __read_mostly tracing_max_latency = (cycle_t)ULONG_MAX; | |
33 | unsigned long __read_mostly tracing_thresh; | |
34 | ||
60a11774 SR |
35 | static int tracing_disabled = 1; |
36 | ||
bc0c38d1 SR |
37 | static long notrace |
38 | ns2usecs(cycle_t nsec) | |
39 | { | |
40 | nsec += 500; | |
41 | do_div(nsec, 1000); | |
42 | return nsec; | |
43 | } | |
44 | ||
53c37c17 IM |
45 | static const int time_sync_freq_max = 128; |
46 | static const cycle_t time_sync_thresh = 100000; | |
47 | ||
48 | static DEFINE_PER_CPU(cycle_t, time_offset); | |
49 | static DEFINE_PER_CPU(cycle_t, prev_cpu_time); | |
50 | static DEFINE_PER_CPU(int, time_sync_count); | |
51 | static DEFINE_PER_CPU(int, time_sync_freq); | |
52 | ||
53 | /* | |
54 | * Global lock which we take every now and then to synchronize | |
55 | * the CPUs time. This method is not warp-safe, but it's good | |
56 | * enough to synchronize slowly diverging time sources and thus | |
57 | * it's good enough for tracing: | |
58 | */ | |
59 | static DEFINE_SPINLOCK(time_sync_lock); | |
60 | static cycle_t prev_global_time; | |
61 | ||
62 | static notrace cycle_t __ftrace_now_sync(cycles_t time, int cpu) | |
63 | { | |
64 | unsigned long flags; | |
65 | ||
66 | spin_lock_irqsave(&time_sync_lock, flags); | |
67 | ||
68 | /* | |
69 | * Update the synchronization frequency: | |
70 | */ | |
71 | if (per_cpu(time_sync_freq, cpu) < time_sync_freq_max) | |
72 | per_cpu(time_sync_freq, cpu) *= 2; | |
73 | per_cpu(time_sync_count, cpu) = per_cpu(time_sync_freq, cpu); | |
74 | ||
75 | if (time < prev_global_time) { | |
76 | per_cpu(time_offset, cpu) += prev_global_time - time; | |
77 | time = prev_global_time; | |
78 | } else { | |
79 | prev_global_time = time; | |
80 | } | |
81 | ||
82 | spin_unlock_irqrestore(&time_sync_lock, flags); | |
83 | ||
84 | return time; | |
85 | } | |
86 | ||
750ed1a4 IM |
87 | notrace cycle_t ftrace_now(int cpu) |
88 | { | |
53c37c17 IM |
89 | cycle_t prev_cpu_time, time, delta_time; |
90 | ||
91 | prev_cpu_time = per_cpu(prev_cpu_time, cpu); | |
92 | time = sched_clock() + per_cpu(time_offset, cpu); | |
93 | delta_time = time-prev_cpu_time; | |
94 | ||
95 | if (unlikely(delta_time > time_sync_thresh || | |
96 | --per_cpu(time_sync_count, cpu) <= 0)) | |
97 | time = __ftrace_now_sync(time, cpu); | |
98 | ||
99 | return time; | |
750ed1a4 IM |
100 | } |
101 | ||
bc0c38d1 SR |
102 | static struct trace_array global_trace; |
103 | ||
104 | static DEFINE_PER_CPU(struct trace_array_cpu, global_trace_cpu); | |
105 | ||
106 | static struct trace_array max_tr; | |
107 | ||
108 | static DEFINE_PER_CPU(struct trace_array_cpu, max_data); | |
109 | ||
110 | static int tracer_enabled; | |
4c11d7ae | 111 | static unsigned long trace_nr_entries = 16384UL; |
bc0c38d1 SR |
112 | |
113 | static struct tracer *trace_types __read_mostly; | |
114 | static struct tracer *current_trace __read_mostly; | |
115 | static int max_tracer_type_len; | |
116 | ||
117 | static DEFINE_MUTEX(trace_types_lock); | |
118 | ||
4c11d7ae SR |
119 | #define ENTRIES_PER_PAGE (PAGE_SIZE / sizeof(struct trace_entry)) |
120 | ||
bc0c38d1 SR |
121 | static int __init set_nr_entries(char *str) |
122 | { | |
123 | if (!str) | |
124 | return 0; | |
125 | trace_nr_entries = simple_strtoul(str, &str, 0); | |
126 | return 1; | |
127 | } | |
128 | __setup("trace_entries=", set_nr_entries); | |
129 | ||
57f50be1 SR |
130 | unsigned long nsecs_to_usecs(unsigned long nsecs) |
131 | { | |
132 | return nsecs / 1000; | |
133 | } | |
134 | ||
bc0c38d1 SR |
135 | enum trace_type { |
136 | __TRACE_FIRST_TYPE = 0, | |
137 | ||
138 | TRACE_FN, | |
139 | TRACE_CTX, | |
140 | ||
141 | __TRACE_LAST_TYPE | |
142 | }; | |
143 | ||
144 | enum trace_flag_type { | |
145 | TRACE_FLAG_IRQS_OFF = 0x01, | |
146 | TRACE_FLAG_NEED_RESCHED = 0x02, | |
147 | TRACE_FLAG_HARDIRQ = 0x04, | |
148 | TRACE_FLAG_SOFTIRQ = 0x08, | |
149 | }; | |
150 | ||
151 | enum trace_iterator_flags { | |
152 | TRACE_ITER_PRINT_PARENT = 0x01, | |
153 | TRACE_ITER_SYM_OFFSET = 0x02, | |
154 | TRACE_ITER_SYM_ADDR = 0x04, | |
155 | TRACE_ITER_VERBOSE = 0x08, | |
f9896bf3 | 156 | TRACE_ITER_RAW = 0x10, |
bc0c38d1 SR |
157 | }; |
158 | ||
159 | #define TRACE_ITER_SYM_MASK \ | |
160 | (TRACE_ITER_PRINT_PARENT|TRACE_ITER_SYM_OFFSET|TRACE_ITER_SYM_ADDR) | |
161 | ||
162 | /* These must match the bit postions above */ | |
163 | static const char *trace_options[] = { | |
164 | "print-parent", | |
165 | "sym-offset", | |
166 | "sym-addr", | |
167 | "verbose", | |
f9896bf3 | 168 | "raw", |
bc0c38d1 SR |
169 | NULL |
170 | }; | |
171 | ||
172 | static unsigned trace_flags; | |
173 | ||
4c11d7ae | 174 | static DEFINE_SPINLOCK(ftrace_max_lock); |
bc0c38d1 SR |
175 | |
176 | /* | |
177 | * Copy the new maximum trace into the separate maximum-trace | |
178 | * structure. (this way the maximum trace is permanently saved, | |
179 | * for later retrieval via /debugfs/tracing/latency_trace) | |
180 | */ | |
4e3c3333 | 181 | static notrace void |
bc0c38d1 SR |
182 | __update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) |
183 | { | |
184 | struct trace_array_cpu *data = tr->data[cpu]; | |
185 | ||
186 | max_tr.cpu = cpu; | |
187 | max_tr.time_start = data->preempt_timestamp; | |
188 | ||
189 | data = max_tr.data[cpu]; | |
190 | data->saved_latency = tracing_max_latency; | |
191 | ||
192 | memcpy(data->comm, tsk->comm, TASK_COMM_LEN); | |
193 | data->pid = tsk->pid; | |
194 | data->uid = tsk->uid; | |
195 | data->nice = tsk->static_prio - 20 - MAX_RT_PRIO; | |
196 | data->policy = tsk->policy; | |
197 | data->rt_priority = tsk->rt_priority; | |
198 | ||
199 | /* record this tasks comm */ | |
200 | tracing_record_cmdline(current); | |
201 | } | |
202 | ||
c7aafc54 IM |
203 | void check_pages(struct trace_array_cpu *data) |
204 | { | |
205 | struct page *page, *tmp; | |
206 | ||
207 | BUG_ON(data->trace_pages.next->prev != &data->trace_pages); | |
208 | BUG_ON(data->trace_pages.prev->next != &data->trace_pages); | |
209 | ||
210 | list_for_each_entry_safe(page, tmp, &data->trace_pages, lru) { | |
211 | BUG_ON(page->lru.next->prev != &page->lru); | |
212 | BUG_ON(page->lru.prev->next != &page->lru); | |
213 | } | |
214 | } | |
215 | ||
216 | void *head_page(struct trace_array_cpu *data) | |
217 | { | |
218 | struct page *page; | |
219 | ||
220 | check_pages(data); | |
221 | if (list_empty(&data->trace_pages)) | |
222 | return NULL; | |
223 | ||
224 | page = list_entry(data->trace_pages.next, struct page, lru); | |
225 | BUG_ON(&page->lru == &data->trace_pages); | |
226 | ||
227 | return page_address(page); | |
228 | } | |
229 | ||
214023c3 SR |
230 | static notrace int |
231 | trace_seq_printf(struct trace_seq *s, const char *fmt, ...) | |
232 | { | |
233 | int len = (PAGE_SIZE - 1) - s->len; | |
234 | va_list ap; | |
b3806b43 | 235 | int ret; |
214023c3 SR |
236 | |
237 | if (!len) | |
238 | return 0; | |
239 | ||
240 | va_start(ap, fmt); | |
b3806b43 | 241 | ret = vsnprintf(s->buffer + s->len, len, fmt, ap); |
214023c3 SR |
242 | va_end(ap); |
243 | ||
b3806b43 SR |
244 | /* If we can't write it all, don't bother writing anything */ |
245 | if (ret > len) | |
246 | return 0; | |
247 | ||
248 | s->len += ret; | |
214023c3 SR |
249 | |
250 | return len; | |
251 | } | |
252 | ||
253 | static notrace int | |
254 | trace_seq_puts(struct trace_seq *s, const char *str) | |
255 | { | |
256 | int len = strlen(str); | |
257 | ||
258 | if (len > ((PAGE_SIZE - 1) - s->len)) | |
b3806b43 | 259 | return 0; |
214023c3 SR |
260 | |
261 | memcpy(s->buffer + s->len, str, len); | |
262 | s->len += len; | |
263 | ||
264 | return len; | |
265 | } | |
266 | ||
267 | static notrace int | |
268 | trace_seq_putc(struct trace_seq *s, unsigned char c) | |
269 | { | |
270 | if (s->len >= (PAGE_SIZE - 1)) | |
271 | return 0; | |
272 | ||
273 | s->buffer[s->len++] = c; | |
274 | ||
275 | return 1; | |
276 | } | |
277 | ||
278 | static notrace void | |
279 | trace_seq_reset(struct trace_seq *s) | |
280 | { | |
281 | s->len = 0; | |
282 | } | |
283 | ||
284 | static notrace void | |
285 | trace_print_seq(struct seq_file *m, struct trace_seq *s) | |
286 | { | |
287 | int len = s->len >= PAGE_SIZE ? PAGE_SIZE - 1 : s->len; | |
288 | ||
289 | s->buffer[len] = 0; | |
290 | seq_puts(m, s->buffer); | |
291 | ||
292 | trace_seq_reset(s); | |
293 | } | |
294 | ||
c7aafc54 IM |
295 | notrace static void |
296 | flip_trace(struct trace_array_cpu *tr1, struct trace_array_cpu *tr2) | |
297 | { | |
298 | struct list_head flip_pages; | |
299 | ||
300 | INIT_LIST_HEAD(&flip_pages); | |
301 | ||
93a588f4 | 302 | memcpy(&tr1->trace_head_idx, &tr2->trace_head_idx, |
c7aafc54 | 303 | sizeof(struct trace_array_cpu) - |
93a588f4 | 304 | offsetof(struct trace_array_cpu, trace_head_idx)); |
c7aafc54 IM |
305 | |
306 | check_pages(tr1); | |
307 | check_pages(tr2); | |
308 | list_splice_init(&tr1->trace_pages, &flip_pages); | |
309 | list_splice_init(&tr2->trace_pages, &tr1->trace_pages); | |
310 | list_splice_init(&flip_pages, &tr2->trace_pages); | |
311 | BUG_ON(!list_empty(&flip_pages)); | |
312 | check_pages(tr1); | |
313 | check_pages(tr2); | |
314 | } | |
315 | ||
bc0c38d1 SR |
316 | notrace void |
317 | update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) | |
318 | { | |
319 | struct trace_array_cpu *data; | |
bc0c38d1 SR |
320 | int i; |
321 | ||
4c11d7ae SR |
322 | WARN_ON_ONCE(!irqs_disabled()); |
323 | spin_lock(&ftrace_max_lock); | |
bc0c38d1 SR |
324 | /* clear out all the previous traces */ |
325 | for_each_possible_cpu(i) { | |
326 | data = tr->data[i]; | |
c7aafc54 | 327 | flip_trace(max_tr.data[i], data); |
89b2f978 | 328 | tracing_reset(data); |
bc0c38d1 SR |
329 | } |
330 | ||
331 | __update_max_tr(tr, tsk, cpu); | |
4c11d7ae | 332 | spin_unlock(&ftrace_max_lock); |
bc0c38d1 SR |
333 | } |
334 | ||
335 | /** | |
336 | * update_max_tr_single - only copy one trace over, and reset the rest | |
337 | * @tr - tracer | |
338 | * @tsk - task with the latency | |
339 | * @cpu - the cpu of the buffer to copy. | |
340 | */ | |
341 | notrace void | |
342 | update_max_tr_single(struct trace_array *tr, struct task_struct *tsk, int cpu) | |
343 | { | |
344 | struct trace_array_cpu *data = tr->data[cpu]; | |
bc0c38d1 SR |
345 | int i; |
346 | ||
4c11d7ae SR |
347 | WARN_ON_ONCE(!irqs_disabled()); |
348 | spin_lock(&ftrace_max_lock); | |
bc0c38d1 SR |
349 | for_each_possible_cpu(i) |
350 | tracing_reset(max_tr.data[i]); | |
351 | ||
c7aafc54 | 352 | flip_trace(max_tr.data[cpu], data); |
89b2f978 | 353 | tracing_reset(data); |
bc0c38d1 SR |
354 | |
355 | __update_max_tr(tr, tsk, cpu); | |
4c11d7ae | 356 | spin_unlock(&ftrace_max_lock); |
bc0c38d1 SR |
357 | } |
358 | ||
359 | int register_tracer(struct tracer *type) | |
360 | { | |
361 | struct tracer *t; | |
362 | int len; | |
363 | int ret = 0; | |
364 | ||
365 | if (!type->name) { | |
366 | pr_info("Tracer must have a name\n"); | |
367 | return -1; | |
368 | } | |
369 | ||
370 | mutex_lock(&trace_types_lock); | |
371 | for (t = trace_types; t; t = t->next) { | |
372 | if (strcmp(type->name, t->name) == 0) { | |
373 | /* already found */ | |
374 | pr_info("Trace %s already registered\n", | |
375 | type->name); | |
376 | ret = -1; | |
377 | goto out; | |
378 | } | |
379 | } | |
380 | ||
60a11774 SR |
381 | #ifdef CONFIG_FTRACE_STARTUP_TEST |
382 | if (type->selftest) { | |
383 | struct tracer *saved_tracer = current_trace; | |
384 | struct trace_array_cpu *data; | |
385 | struct trace_array *tr = &global_trace; | |
386 | int saved_ctrl = tr->ctrl; | |
387 | int i; | |
388 | /* | |
389 | * Run a selftest on this tracer. | |
390 | * Here we reset the trace buffer, and set the current | |
391 | * tracer to be this tracer. The tracer can then run some | |
392 | * internal tracing to verify that everything is in order. | |
393 | * If we fail, we do not register this tracer. | |
394 | */ | |
395 | for_each_possible_cpu(i) { | |
60a11774 | 396 | data = tr->data[i]; |
c7aafc54 IM |
397 | if (!head_page(data)) |
398 | continue; | |
60a11774 SR |
399 | tracing_reset(data); |
400 | } | |
401 | current_trace = type; | |
402 | tr->ctrl = 0; | |
403 | /* the test is responsible for initializing and enabling */ | |
404 | pr_info("Testing tracer %s: ", type->name); | |
405 | ret = type->selftest(type, tr); | |
406 | /* the test is responsible for resetting too */ | |
407 | current_trace = saved_tracer; | |
408 | tr->ctrl = saved_ctrl; | |
409 | if (ret) { | |
410 | printk(KERN_CONT "FAILED!\n"); | |
411 | goto out; | |
412 | } | |
1d4db00a SR |
413 | /* Only reset on passing, to avoid touching corrupted buffers */ |
414 | for_each_possible_cpu(i) { | |
415 | data = tr->data[i]; | |
416 | if (!head_page(data)) | |
417 | continue; | |
418 | tracing_reset(data); | |
419 | } | |
60a11774 SR |
420 | printk(KERN_CONT "PASSED\n"); |
421 | } | |
422 | #endif | |
423 | ||
bc0c38d1 SR |
424 | type->next = trace_types; |
425 | trace_types = type; | |
426 | len = strlen(type->name); | |
427 | if (len > max_tracer_type_len) | |
428 | max_tracer_type_len = len; | |
60a11774 | 429 | |
bc0c38d1 SR |
430 | out: |
431 | mutex_unlock(&trace_types_lock); | |
432 | ||
433 | return ret; | |
434 | } | |
435 | ||
436 | void unregister_tracer(struct tracer *type) | |
437 | { | |
438 | struct tracer **t; | |
439 | int len; | |
440 | ||
441 | mutex_lock(&trace_types_lock); | |
442 | for (t = &trace_types; *t; t = &(*t)->next) { | |
443 | if (*t == type) | |
444 | goto found; | |
445 | } | |
446 | pr_info("Trace %s not registered\n", type->name); | |
447 | goto out; | |
448 | ||
449 | found: | |
450 | *t = (*t)->next; | |
451 | if (strlen(type->name) != max_tracer_type_len) | |
452 | goto out; | |
453 | ||
454 | max_tracer_type_len = 0; | |
455 | for (t = &trace_types; *t; t = &(*t)->next) { | |
456 | len = strlen((*t)->name); | |
457 | if (len > max_tracer_type_len) | |
458 | max_tracer_type_len = len; | |
459 | } | |
460 | out: | |
461 | mutex_unlock(&trace_types_lock); | |
462 | } | |
463 | ||
4e3c3333 | 464 | notrace void tracing_reset(struct trace_array_cpu *data) |
bc0c38d1 SR |
465 | { |
466 | data->trace_idx = 0; | |
93a588f4 SR |
467 | data->trace_head = data->trace_tail = head_page(data); |
468 | data->trace_head_idx = 0; | |
469 | data->trace_tail_idx = 0; | |
bc0c38d1 SR |
470 | } |
471 | ||
472 | #ifdef CONFIG_FTRACE | |
4e3c3333 | 473 | static notrace void |
bc0c38d1 SR |
474 | function_trace_call(unsigned long ip, unsigned long parent_ip) |
475 | { | |
476 | struct trace_array *tr = &global_trace; | |
477 | struct trace_array_cpu *data; | |
478 | unsigned long flags; | |
479 | long disabled; | |
480 | int cpu; | |
481 | ||
482 | if (unlikely(!tracer_enabled)) | |
483 | return; | |
484 | ||
18cef379 | 485 | local_irq_save(flags); |
bc0c38d1 SR |
486 | cpu = raw_smp_processor_id(); |
487 | data = tr->data[cpu]; | |
488 | disabled = atomic_inc_return(&data->disabled); | |
489 | ||
490 | if (likely(disabled == 1)) | |
491 | ftrace(tr, data, ip, parent_ip, flags); | |
492 | ||
493 | atomic_dec(&data->disabled); | |
18cef379 | 494 | local_irq_restore(flags); |
bc0c38d1 SR |
495 | } |
496 | ||
497 | static struct ftrace_ops trace_ops __read_mostly = | |
498 | { | |
499 | .func = function_trace_call, | |
500 | }; | |
501 | #endif | |
502 | ||
503 | notrace void tracing_start_function_trace(void) | |
504 | { | |
505 | register_ftrace_function(&trace_ops); | |
506 | } | |
507 | ||
508 | notrace void tracing_stop_function_trace(void) | |
509 | { | |
510 | unregister_ftrace_function(&trace_ops); | |
511 | } | |
512 | ||
513 | #define SAVED_CMDLINES 128 | |
514 | static unsigned map_pid_to_cmdline[PID_MAX_DEFAULT+1]; | |
515 | static unsigned map_cmdline_to_pid[SAVED_CMDLINES]; | |
516 | static char saved_cmdlines[SAVED_CMDLINES][TASK_COMM_LEN]; | |
517 | static int cmdline_idx; | |
518 | static DEFINE_SPINLOCK(trace_cmdline_lock); | |
519 | atomic_t trace_record_cmdline_disabled; | |
520 | ||
521 | static void trace_init_cmdlines(void) | |
522 | { | |
523 | memset(&map_pid_to_cmdline, -1, sizeof(map_pid_to_cmdline)); | |
524 | memset(&map_cmdline_to_pid, -1, sizeof(map_cmdline_to_pid)); | |
525 | cmdline_idx = 0; | |
526 | } | |
527 | ||
528 | notrace void trace_stop_cmdline_recording(void); | |
529 | ||
4e3c3333 | 530 | static notrace void trace_save_cmdline(struct task_struct *tsk) |
bc0c38d1 SR |
531 | { |
532 | unsigned map; | |
533 | unsigned idx; | |
534 | ||
535 | if (!tsk->pid || unlikely(tsk->pid > PID_MAX_DEFAULT)) | |
536 | return; | |
537 | ||
538 | /* | |
539 | * It's not the end of the world if we don't get | |
540 | * the lock, but we also don't want to spin | |
541 | * nor do we want to disable interrupts, | |
542 | * so if we miss here, then better luck next time. | |
543 | */ | |
544 | if (!spin_trylock(&trace_cmdline_lock)) | |
545 | return; | |
546 | ||
547 | idx = map_pid_to_cmdline[tsk->pid]; | |
548 | if (idx >= SAVED_CMDLINES) { | |
549 | idx = (cmdline_idx + 1) % SAVED_CMDLINES; | |
550 | ||
551 | map = map_cmdline_to_pid[idx]; | |
552 | if (map <= PID_MAX_DEFAULT) | |
553 | map_pid_to_cmdline[map] = (unsigned)-1; | |
554 | ||
555 | map_pid_to_cmdline[tsk->pid] = idx; | |
556 | ||
557 | cmdline_idx = idx; | |
558 | } | |
559 | ||
560 | memcpy(&saved_cmdlines[idx], tsk->comm, TASK_COMM_LEN); | |
561 | ||
562 | spin_unlock(&trace_cmdline_lock); | |
563 | } | |
564 | ||
565 | static notrace char *trace_find_cmdline(int pid) | |
566 | { | |
567 | char *cmdline = "<...>"; | |
568 | unsigned map; | |
569 | ||
570 | if (!pid) | |
571 | return "<idle>"; | |
572 | ||
573 | if (pid > PID_MAX_DEFAULT) | |
574 | goto out; | |
575 | ||
576 | map = map_pid_to_cmdline[pid]; | |
577 | if (map >= SAVED_CMDLINES) | |
578 | goto out; | |
579 | ||
580 | cmdline = saved_cmdlines[map]; | |
581 | ||
582 | out: | |
583 | return cmdline; | |
584 | } | |
585 | ||
586 | notrace void tracing_record_cmdline(struct task_struct *tsk) | |
587 | { | |
588 | if (atomic_read(&trace_record_cmdline_disabled)) | |
589 | return; | |
590 | ||
591 | trace_save_cmdline(tsk); | |
592 | } | |
593 | ||
93a588f4 SR |
594 | static inline notrace struct list_head * |
595 | trace_next_list(struct trace_array_cpu *data, struct list_head *next) | |
596 | { | |
597 | /* | |
598 | * Roundrobin - but skip the head (which is not a real page): | |
599 | */ | |
600 | next = next->next; | |
601 | if (unlikely(next == &data->trace_pages)) | |
602 | next = next->next; | |
603 | BUG_ON(next == &data->trace_pages); | |
604 | ||
605 | return next; | |
606 | } | |
607 | ||
608 | static inline notrace void * | |
609 | trace_next_page(struct trace_array_cpu *data, void *addr) | |
610 | { | |
611 | struct list_head *next; | |
612 | struct page *page; | |
613 | ||
614 | page = virt_to_page(addr); | |
615 | ||
616 | next = trace_next_list(data, &page->lru); | |
617 | page = list_entry(next, struct page, lru); | |
618 | ||
619 | return page_address(page); | |
620 | } | |
621 | ||
bc0c38d1 | 622 | static inline notrace struct trace_entry * |
c7aafc54 | 623 | tracing_get_trace_entry(struct trace_array *tr, struct trace_array_cpu *data) |
bc0c38d1 SR |
624 | { |
625 | unsigned long idx, idx_next; | |
626 | struct trace_entry *entry; | |
627 | ||
4c11d7ae | 628 | data->trace_idx++; |
93a588f4 | 629 | idx = data->trace_head_idx; |
bc0c38d1 SR |
630 | idx_next = idx + 1; |
631 | ||
c7aafc54 IM |
632 | BUG_ON(idx * TRACE_ENTRY_SIZE >= PAGE_SIZE); |
633 | ||
93a588f4 | 634 | entry = data->trace_head + idx * TRACE_ENTRY_SIZE; |
4c11d7ae SR |
635 | |
636 | if (unlikely(idx_next >= ENTRIES_PER_PAGE)) { | |
93a588f4 | 637 | data->trace_head = trace_next_page(data, data->trace_head); |
bc0c38d1 SR |
638 | idx_next = 0; |
639 | } | |
640 | ||
93a588f4 SR |
641 | if (data->trace_head == data->trace_tail && |
642 | idx_next == data->trace_tail_idx) { | |
643 | /* overrun */ | |
644 | data->trace_tail_idx++; | |
645 | if (data->trace_tail_idx >= ENTRIES_PER_PAGE) { | |
646 | data->trace_tail = | |
647 | trace_next_page(data, data->trace_tail); | |
648 | data->trace_tail_idx = 0; | |
649 | } | |
650 | } | |
651 | ||
652 | data->trace_head_idx = idx_next; | |
bc0c38d1 SR |
653 | |
654 | return entry; | |
655 | } | |
656 | ||
657 | static inline notrace void | |
c7aafc54 | 658 | tracing_generic_entry_update(struct trace_entry *entry, unsigned long flags) |
bc0c38d1 SR |
659 | { |
660 | struct task_struct *tsk = current; | |
661 | unsigned long pc; | |
662 | ||
663 | pc = preempt_count(); | |
664 | ||
c7aafc54 IM |
665 | entry->preempt_count = pc & 0xff; |
666 | entry->pid = tsk->pid; | |
750ed1a4 | 667 | entry->t = ftrace_now(raw_smp_processor_id()); |
bc0c38d1 SR |
668 | entry->flags = (irqs_disabled_flags(flags) ? TRACE_FLAG_IRQS_OFF : 0) | |
669 | ((pc & HARDIRQ_MASK) ? TRACE_FLAG_HARDIRQ : 0) | | |
670 | ((pc & SOFTIRQ_MASK) ? TRACE_FLAG_SOFTIRQ : 0) | | |
671 | (need_resched() ? TRACE_FLAG_NEED_RESCHED : 0); | |
672 | } | |
673 | ||
674 | notrace void | |
675 | ftrace(struct trace_array *tr, struct trace_array_cpu *data, | |
c7aafc54 | 676 | unsigned long ip, unsigned long parent_ip, unsigned long flags) |
bc0c38d1 SR |
677 | { |
678 | struct trace_entry *entry; | |
679 | ||
b3806b43 | 680 | spin_lock(&data->lock); |
c7aafc54 | 681 | entry = tracing_get_trace_entry(tr, data); |
bc0c38d1 | 682 | tracing_generic_entry_update(entry, flags); |
c7aafc54 IM |
683 | entry->type = TRACE_FN; |
684 | entry->fn.ip = ip; | |
685 | entry->fn.parent_ip = parent_ip; | |
b3806b43 | 686 | spin_unlock(&data->lock); |
bc0c38d1 SR |
687 | } |
688 | ||
689 | notrace void | |
690 | tracing_sched_switch_trace(struct trace_array *tr, | |
691 | struct trace_array_cpu *data, | |
692 | struct task_struct *prev, struct task_struct *next, | |
693 | unsigned long flags) | |
694 | { | |
695 | struct trace_entry *entry; | |
696 | ||
b3806b43 | 697 | spin_lock(&data->lock); |
c7aafc54 | 698 | entry = tracing_get_trace_entry(tr, data); |
bc0c38d1 SR |
699 | tracing_generic_entry_update(entry, flags); |
700 | entry->type = TRACE_CTX; | |
701 | entry->ctx.prev_pid = prev->pid; | |
702 | entry->ctx.prev_prio = prev->prio; | |
703 | entry->ctx.prev_state = prev->state; | |
704 | entry->ctx.next_pid = next->pid; | |
705 | entry->ctx.next_prio = next->prio; | |
b3806b43 | 706 | spin_unlock(&data->lock); |
bc0c38d1 SR |
707 | } |
708 | ||
709 | enum trace_file_type { | |
710 | TRACE_FILE_LAT_FMT = 1, | |
711 | }; | |
712 | ||
713 | static struct trace_entry * | |
4c11d7ae SR |
714 | trace_entry_idx(struct trace_array *tr, struct trace_array_cpu *data, |
715 | struct trace_iterator *iter, int cpu) | |
bc0c38d1 | 716 | { |
4c11d7ae SR |
717 | struct page *page; |
718 | struct trace_entry *array; | |
bc0c38d1 | 719 | |
4c11d7ae | 720 | if (iter->next_idx[cpu] >= tr->entries || |
b3806b43 SR |
721 | iter->next_idx[cpu] >= data->trace_idx || |
722 | (data->trace_head == data->trace_tail && | |
723 | data->trace_head_idx == data->trace_tail_idx)) | |
bc0c38d1 SR |
724 | return NULL; |
725 | ||
4c11d7ae | 726 | if (!iter->next_page[cpu]) { |
93a588f4 SR |
727 | /* Initialize the iterator for this cpu trace buffer */ |
728 | WARN_ON(!data->trace_tail); | |
729 | page = virt_to_page(data->trace_tail); | |
730 | iter->next_page[cpu] = &page->lru; | |
731 | iter->next_page_idx[cpu] = data->trace_tail_idx; | |
4c11d7ae | 732 | } |
bc0c38d1 | 733 | |
4c11d7ae | 734 | page = list_entry(iter->next_page[cpu], struct page, lru); |
c7aafc54 IM |
735 | BUG_ON(&data->trace_pages == &page->lru); |
736 | ||
4c11d7ae SR |
737 | array = page_address(page); |
738 | ||
93a588f4 SR |
739 | /* Still possible to catch up to the tail */ |
740 | if (iter->next_idx[cpu] && array == data->trace_tail && | |
741 | iter->next_page_idx[cpu] == data->trace_tail_idx) | |
742 | return NULL; | |
743 | ||
744 | WARN_ON(iter->next_page_idx[cpu] >= ENTRIES_PER_PAGE); | |
4c11d7ae | 745 | return &array[iter->next_page_idx[cpu]]; |
bc0c38d1 SR |
746 | } |
747 | ||
748 | static struct notrace trace_entry * | |
749 | find_next_entry(struct trace_iterator *iter, int *ent_cpu) | |
750 | { | |
751 | struct trace_array *tr = iter->tr; | |
752 | struct trace_entry *ent, *next = NULL; | |
753 | int next_cpu = -1; | |
754 | int cpu; | |
755 | ||
756 | for_each_possible_cpu(cpu) { | |
c7aafc54 | 757 | if (!head_page(tr->data[cpu])) |
bc0c38d1 | 758 | continue; |
4c11d7ae | 759 | ent = trace_entry_idx(tr, tr->data[cpu], iter, cpu); |
cdd31cd2 IM |
760 | /* |
761 | * Pick the entry with the smallest timestamp: | |
762 | */ | |
763 | if (ent && (!next || ent->t < next->t)) { | |
bc0c38d1 SR |
764 | next = ent; |
765 | next_cpu = cpu; | |
766 | } | |
767 | } | |
768 | ||
769 | if (ent_cpu) | |
770 | *ent_cpu = next_cpu; | |
771 | ||
772 | return next; | |
773 | } | |
774 | ||
8c523a9d | 775 | static notrace void trace_iterator_increment(struct trace_iterator *iter) |
bc0c38d1 | 776 | { |
b3806b43 SR |
777 | iter->idx++; |
778 | iter->next_idx[iter->cpu]++; | |
779 | iter->next_page_idx[iter->cpu]++; | |
8c523a9d | 780 | |
b3806b43 SR |
781 | if (iter->next_page_idx[iter->cpu] >= ENTRIES_PER_PAGE) { |
782 | struct trace_array_cpu *data = iter->tr->data[iter->cpu]; | |
bc0c38d1 | 783 | |
b3806b43 SR |
784 | iter->next_page_idx[iter->cpu] = 0; |
785 | iter->next_page[iter->cpu] = | |
786 | trace_next_list(data, iter->next_page[iter->cpu]); | |
787 | } | |
788 | } | |
bc0c38d1 | 789 | |
8c523a9d | 790 | static notrace void trace_consume(struct trace_iterator *iter) |
b3806b43 SR |
791 | { |
792 | struct trace_array_cpu *data = iter->tr->data[iter->cpu]; | |
793 | ||
794 | data->trace_tail_idx++; | |
795 | if (data->trace_tail_idx >= ENTRIES_PER_PAGE) { | |
796 | data->trace_tail = trace_next_page(data, data->trace_tail); | |
797 | data->trace_tail_idx = 0; | |
798 | } | |
4e3c3333 | 799 | |
b3806b43 SR |
800 | /* Check if we empty it, then reset the index */ |
801 | if (data->trace_head == data->trace_tail && | |
802 | data->trace_head_idx == data->trace_tail_idx) | |
803 | data->trace_idx = 0; | |
b3806b43 SR |
804 | } |
805 | ||
8c523a9d | 806 | static notrace void *find_next_entry_inc(struct trace_iterator *iter) |
b3806b43 SR |
807 | { |
808 | struct trace_entry *next; | |
809 | int next_cpu = -1; | |
810 | ||
811 | next = find_next_entry(iter, &next_cpu); | |
93a588f4 | 812 | |
4e3c3333 IM |
813 | iter->prev_ent = iter->ent; |
814 | iter->prev_cpu = iter->cpu; | |
815 | ||
bc0c38d1 SR |
816 | iter->ent = next; |
817 | iter->cpu = next_cpu; | |
818 | ||
b3806b43 SR |
819 | if (next) |
820 | trace_iterator_increment(iter); | |
821 | ||
bc0c38d1 SR |
822 | return next ? iter : NULL; |
823 | } | |
824 | ||
4e3c3333 | 825 | static notrace void *s_next(struct seq_file *m, void *v, loff_t *pos) |
bc0c38d1 SR |
826 | { |
827 | struct trace_iterator *iter = m->private; | |
bc0c38d1 SR |
828 | void *last_ent = iter->ent; |
829 | int i = (int)*pos; | |
4e3c3333 | 830 | void *ent; |
bc0c38d1 SR |
831 | |
832 | (*pos)++; | |
833 | ||
834 | /* can't go backwards */ | |
835 | if (iter->idx > i) | |
836 | return NULL; | |
837 | ||
838 | if (iter->idx < 0) | |
839 | ent = find_next_entry_inc(iter); | |
840 | else | |
841 | ent = iter; | |
842 | ||
843 | while (ent && iter->idx < i) | |
844 | ent = find_next_entry_inc(iter); | |
845 | ||
846 | iter->pos = *pos; | |
847 | ||
848 | if (last_ent && !ent) | |
849 | seq_puts(m, "\n\nvim:ft=help\n"); | |
850 | ||
851 | return ent; | |
852 | } | |
853 | ||
854 | static void *s_start(struct seq_file *m, loff_t *pos) | |
855 | { | |
856 | struct trace_iterator *iter = m->private; | |
857 | void *p = NULL; | |
858 | loff_t l = 0; | |
859 | int i; | |
860 | ||
861 | mutex_lock(&trace_types_lock); | |
862 | ||
863 | if (!current_trace || current_trace != iter->trace) | |
864 | return NULL; | |
865 | ||
866 | atomic_inc(&trace_record_cmdline_disabled); | |
867 | ||
868 | /* let the tracer grab locks here if needed */ | |
869 | if (current_trace->start) | |
870 | current_trace->start(iter); | |
871 | ||
872 | if (*pos != iter->pos) { | |
873 | iter->ent = NULL; | |
874 | iter->cpu = 0; | |
875 | iter->idx = -1; | |
4e3c3333 IM |
876 | iter->prev_ent = NULL; |
877 | iter->prev_cpu = -1; | |
bc0c38d1 | 878 | |
4c11d7ae | 879 | for_each_possible_cpu(i) { |
bc0c38d1 | 880 | iter->next_idx[i] = 0; |
4c11d7ae SR |
881 | iter->next_page[i] = NULL; |
882 | } | |
bc0c38d1 SR |
883 | |
884 | for (p = iter; p && l < *pos; p = s_next(m, p, &l)) | |
885 | ; | |
886 | ||
887 | } else { | |
4c11d7ae | 888 | l = *pos - 1; |
bc0c38d1 SR |
889 | p = s_next(m, p, &l); |
890 | } | |
891 | ||
892 | return p; | |
893 | } | |
894 | ||
895 | static void s_stop(struct seq_file *m, void *p) | |
896 | { | |
897 | struct trace_iterator *iter = m->private; | |
898 | ||
899 | atomic_dec(&trace_record_cmdline_disabled); | |
900 | ||
901 | /* let the tracer release locks here if needed */ | |
902 | if (current_trace && current_trace == iter->trace && iter->trace->stop) | |
903 | iter->trace->stop(iter); | |
904 | ||
905 | mutex_unlock(&trace_types_lock); | |
906 | } | |
907 | ||
b3806b43 | 908 | static int |
214023c3 | 909 | seq_print_sym_short(struct trace_seq *s, const char *fmt, unsigned long address) |
bc0c38d1 SR |
910 | { |
911 | #ifdef CONFIG_KALLSYMS | |
912 | char str[KSYM_SYMBOL_LEN]; | |
913 | ||
914 | kallsyms_lookup(address, NULL, NULL, NULL, str); | |
915 | ||
b3806b43 | 916 | return trace_seq_printf(s, fmt, str); |
bc0c38d1 | 917 | #endif |
b3806b43 | 918 | return 1; |
bc0c38d1 SR |
919 | } |
920 | ||
b3806b43 | 921 | static int |
214023c3 SR |
922 | seq_print_sym_offset(struct trace_seq *s, const char *fmt, |
923 | unsigned long address) | |
bc0c38d1 SR |
924 | { |
925 | #ifdef CONFIG_KALLSYMS | |
926 | char str[KSYM_SYMBOL_LEN]; | |
927 | ||
928 | sprint_symbol(str, address); | |
b3806b43 | 929 | return trace_seq_printf(s, fmt, str); |
bc0c38d1 | 930 | #endif |
b3806b43 | 931 | return 1; |
bc0c38d1 SR |
932 | } |
933 | ||
934 | #ifndef CONFIG_64BIT | |
935 | # define IP_FMT "%08lx" | |
936 | #else | |
937 | # define IP_FMT "%016lx" | |
938 | #endif | |
939 | ||
b3806b43 | 940 | static notrace int |
214023c3 | 941 | seq_print_ip_sym(struct trace_seq *s, unsigned long ip, unsigned long sym_flags) |
bc0c38d1 | 942 | { |
b3806b43 SR |
943 | int ret; |
944 | ||
945 | if (!ip) | |
946 | return trace_seq_printf(s, "0"); | |
bc0c38d1 SR |
947 | |
948 | if (sym_flags & TRACE_ITER_SYM_OFFSET) | |
b3806b43 | 949 | ret = seq_print_sym_offset(s, "%s", ip); |
bc0c38d1 | 950 | else |
b3806b43 SR |
951 | ret = seq_print_sym_short(s, "%s", ip); |
952 | ||
953 | if (!ret) | |
954 | return 0; | |
bc0c38d1 SR |
955 | |
956 | if (sym_flags & TRACE_ITER_SYM_ADDR) | |
b3806b43 SR |
957 | ret = trace_seq_printf(s, " <" IP_FMT ">", ip); |
958 | return ret; | |
bc0c38d1 SR |
959 | } |
960 | ||
4e3c3333 | 961 | static notrace void print_lat_help_header(struct seq_file *m) |
bc0c38d1 SR |
962 | { |
963 | seq_puts(m, "# _------=> CPU# \n"); | |
964 | seq_puts(m, "# / _-----=> irqs-off \n"); | |
965 | seq_puts(m, "# | / _----=> need-resched \n"); | |
966 | seq_puts(m, "# || / _---=> hardirq/softirq \n"); | |
967 | seq_puts(m, "# ||| / _--=> preempt-depth \n"); | |
968 | seq_puts(m, "# |||| / \n"); | |
969 | seq_puts(m, "# ||||| delay \n"); | |
970 | seq_puts(m, "# cmd pid ||||| time | caller \n"); | |
971 | seq_puts(m, "# \\ / ||||| \\ | / \n"); | |
972 | } | |
973 | ||
4e3c3333 | 974 | static notrace void print_func_help_header(struct seq_file *m) |
bc0c38d1 SR |
975 | { |
976 | seq_puts(m, "# TASK-PID CPU# TIMESTAMP FUNCTION\n"); | |
977 | seq_puts(m, "# | | | | |\n"); | |
978 | } | |
979 | ||
980 | ||
4e3c3333 | 981 | static notrace void |
bc0c38d1 SR |
982 | print_trace_header(struct seq_file *m, struct trace_iterator *iter) |
983 | { | |
984 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); | |
985 | struct trace_array *tr = iter->tr; | |
986 | struct trace_array_cpu *data = tr->data[tr->cpu]; | |
987 | struct tracer *type = current_trace; | |
4c11d7ae SR |
988 | unsigned long total = 0; |
989 | unsigned long entries = 0; | |
bc0c38d1 SR |
990 | int cpu; |
991 | const char *name = "preemption"; | |
992 | ||
993 | if (type) | |
994 | name = type->name; | |
995 | ||
996 | for_each_possible_cpu(cpu) { | |
c7aafc54 | 997 | if (head_page(tr->data[cpu])) { |
4c11d7ae SR |
998 | total += tr->data[cpu]->trace_idx; |
999 | if (tr->data[cpu]->trace_idx > tr->entries) | |
bc0c38d1 | 1000 | entries += tr->entries; |
4c11d7ae | 1001 | else |
bc0c38d1 SR |
1002 | entries += tr->data[cpu]->trace_idx; |
1003 | } | |
1004 | } | |
1005 | ||
1006 | seq_printf(m, "%s latency trace v1.1.5 on %s\n", | |
1007 | name, UTS_RELEASE); | |
1008 | seq_puts(m, "-----------------------------------" | |
1009 | "---------------------------------\n"); | |
1010 | seq_printf(m, " latency: %lu us, #%lu/%lu, CPU#%d |" | |
1011 | " (M:%s VP:%d, KP:%d, SP:%d HP:%d", | |
57f50be1 | 1012 | nsecs_to_usecs(data->saved_latency), |
bc0c38d1 | 1013 | entries, |
4c11d7ae | 1014 | total, |
bc0c38d1 SR |
1015 | tr->cpu, |
1016 | #if defined(CONFIG_PREEMPT_NONE) | |
1017 | "server", | |
1018 | #elif defined(CONFIG_PREEMPT_VOLUNTARY) | |
1019 | "desktop", | |
1020 | #elif defined(CONFIG_PREEMPT_DESKTOP) | |
1021 | "preempt", | |
1022 | #else | |
1023 | "unknown", | |
1024 | #endif | |
1025 | /* These are reserved for later use */ | |
1026 | 0, 0, 0, 0); | |
1027 | #ifdef CONFIG_SMP | |
1028 | seq_printf(m, " #P:%d)\n", num_online_cpus()); | |
1029 | #else | |
1030 | seq_puts(m, ")\n"); | |
1031 | #endif | |
1032 | seq_puts(m, " -----------------\n"); | |
1033 | seq_printf(m, " | task: %.16s-%d " | |
1034 | "(uid:%d nice:%ld policy:%ld rt_prio:%ld)\n", | |
1035 | data->comm, data->pid, data->uid, data->nice, | |
1036 | data->policy, data->rt_priority); | |
1037 | seq_puts(m, " -----------------\n"); | |
1038 | ||
1039 | if (data->critical_start) { | |
1040 | seq_puts(m, " => started at: "); | |
214023c3 SR |
1041 | seq_print_ip_sym(&iter->seq, data->critical_start, sym_flags); |
1042 | trace_print_seq(m, &iter->seq); | |
bc0c38d1 | 1043 | seq_puts(m, "\n => ended at: "); |
214023c3 SR |
1044 | seq_print_ip_sym(&iter->seq, data->critical_end, sym_flags); |
1045 | trace_print_seq(m, &iter->seq); | |
bc0c38d1 SR |
1046 | seq_puts(m, "\n"); |
1047 | } | |
1048 | ||
1049 | seq_puts(m, "\n"); | |
1050 | } | |
1051 | ||
4e3c3333 | 1052 | static notrace void |
214023c3 | 1053 | lat_print_generic(struct trace_seq *s, struct trace_entry *entry, int cpu) |
bc0c38d1 SR |
1054 | { |
1055 | int hardirq, softirq; | |
1056 | char *comm; | |
1057 | ||
1058 | comm = trace_find_cmdline(entry->pid); | |
1059 | ||
214023c3 SR |
1060 | trace_seq_printf(s, "%8.8s-%-5d ", comm, entry->pid); |
1061 | trace_seq_printf(s, "%d", cpu); | |
1062 | trace_seq_printf(s, "%c%c", | |
1063 | (entry->flags & TRACE_FLAG_IRQS_OFF) ? 'd' : '.', | |
1064 | ((entry->flags & TRACE_FLAG_NEED_RESCHED) ? 'N' : '.')); | |
bc0c38d1 SR |
1065 | |
1066 | hardirq = entry->flags & TRACE_FLAG_HARDIRQ; | |
1067 | softirq = entry->flags & TRACE_FLAG_SOFTIRQ; | |
1068 | if (hardirq && softirq) | |
214023c3 | 1069 | trace_seq_putc(s, 'H'); |
bc0c38d1 SR |
1070 | else { |
1071 | if (hardirq) | |
214023c3 | 1072 | trace_seq_putc(s, 'h'); |
bc0c38d1 SR |
1073 | else { |
1074 | if (softirq) | |
214023c3 | 1075 | trace_seq_putc(s, 's'); |
bc0c38d1 | 1076 | else |
214023c3 | 1077 | trace_seq_putc(s, '.'); |
bc0c38d1 SR |
1078 | } |
1079 | } | |
1080 | ||
1081 | if (entry->preempt_count) | |
214023c3 | 1082 | trace_seq_printf(s, "%x", entry->preempt_count); |
bc0c38d1 | 1083 | else |
214023c3 | 1084 | trace_seq_puts(s, "."); |
bc0c38d1 SR |
1085 | } |
1086 | ||
1087 | unsigned long preempt_mark_thresh = 100; | |
1088 | ||
4e3c3333 | 1089 | static notrace void |
214023c3 | 1090 | lat_print_timestamp(struct trace_seq *s, unsigned long long abs_usecs, |
bc0c38d1 SR |
1091 | unsigned long rel_usecs) |
1092 | { | |
214023c3 | 1093 | trace_seq_printf(s, " %4lldus", abs_usecs); |
bc0c38d1 | 1094 | if (rel_usecs > preempt_mark_thresh) |
214023c3 | 1095 | trace_seq_puts(s, "!: "); |
bc0c38d1 | 1096 | else if (rel_usecs > 1) |
214023c3 | 1097 | trace_seq_puts(s, "+: "); |
bc0c38d1 | 1098 | else |
214023c3 | 1099 | trace_seq_puts(s, " : "); |
bc0c38d1 SR |
1100 | } |
1101 | ||
1102 | static const char state_to_char[] = TASK_STATE_TO_CHAR_STR; | |
1103 | ||
f9896bf3 | 1104 | static notrace int |
214023c3 | 1105 | print_lat_fmt(struct trace_iterator *iter, unsigned int trace_idx, int cpu) |
bc0c38d1 | 1106 | { |
214023c3 | 1107 | struct trace_seq *s = &iter->seq; |
bc0c38d1 SR |
1108 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); |
1109 | struct trace_entry *next_entry = find_next_entry(iter, NULL); | |
1110 | unsigned long verbose = (trace_flags & TRACE_ITER_VERBOSE); | |
1111 | struct trace_entry *entry = iter->ent; | |
1112 | unsigned long abs_usecs; | |
1113 | unsigned long rel_usecs; | |
1114 | char *comm; | |
1115 | int S; | |
1116 | ||
1117 | if (!next_entry) | |
1118 | next_entry = entry; | |
1119 | rel_usecs = ns2usecs(next_entry->t - entry->t); | |
1120 | abs_usecs = ns2usecs(entry->t - iter->tr->time_start); | |
1121 | ||
1122 | if (verbose) { | |
1123 | comm = trace_find_cmdline(entry->pid); | |
214023c3 SR |
1124 | trace_seq_printf(s, "%16s %5d %d %d %08x %08x [%08lx]" |
1125 | " %ld.%03ldms (+%ld.%03ldms): ", | |
1126 | comm, | |
1127 | entry->pid, cpu, entry->flags, | |
1128 | entry->preempt_count, trace_idx, | |
1129 | ns2usecs(entry->t), | |
1130 | abs_usecs/1000, | |
1131 | abs_usecs % 1000, rel_usecs/1000, | |
1132 | rel_usecs % 1000); | |
bc0c38d1 | 1133 | } else { |
214023c3 SR |
1134 | lat_print_generic(s, entry, cpu); |
1135 | lat_print_timestamp(s, abs_usecs, rel_usecs); | |
bc0c38d1 SR |
1136 | } |
1137 | switch (entry->type) { | |
1138 | case TRACE_FN: | |
214023c3 SR |
1139 | seq_print_ip_sym(s, entry->fn.ip, sym_flags); |
1140 | trace_seq_puts(s, " ("); | |
1141 | seq_print_ip_sym(s, entry->fn.parent_ip, sym_flags); | |
1142 | trace_seq_puts(s, ")\n"); | |
bc0c38d1 SR |
1143 | break; |
1144 | case TRACE_CTX: | |
1145 | S = entry->ctx.prev_state < sizeof(state_to_char) ? | |
1146 | state_to_char[entry->ctx.prev_state] : 'X'; | |
1147 | comm = trace_find_cmdline(entry->ctx.next_pid); | |
214023c3 SR |
1148 | trace_seq_printf(s, " %d:%d:%c --> %d:%d %s\n", |
1149 | entry->ctx.prev_pid, | |
1150 | entry->ctx.prev_prio, | |
1151 | S, | |
1152 | entry->ctx.next_pid, | |
1153 | entry->ctx.next_prio, | |
1154 | comm); | |
bc0c38d1 | 1155 | break; |
89b2f978 | 1156 | default: |
214023c3 | 1157 | trace_seq_printf(s, "Unknown type %d\n", entry->type); |
bc0c38d1 | 1158 | } |
f9896bf3 | 1159 | return 1; |
bc0c38d1 SR |
1160 | } |
1161 | ||
f9896bf3 | 1162 | static notrace int print_trace_fmt(struct trace_iterator *iter) |
bc0c38d1 | 1163 | { |
214023c3 | 1164 | struct trace_seq *s = &iter->seq; |
bc0c38d1 | 1165 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); |
4e3c3333 | 1166 | struct trace_entry *entry; |
bc0c38d1 SR |
1167 | unsigned long usec_rem; |
1168 | unsigned long long t; | |
1169 | unsigned long secs; | |
1170 | char *comm; | |
1171 | int S; | |
b3806b43 | 1172 | int ret; |
bc0c38d1 | 1173 | |
4e3c3333 IM |
1174 | entry = iter->ent; |
1175 | ||
bc0c38d1 SR |
1176 | comm = trace_find_cmdline(iter->ent->pid); |
1177 | ||
cdd31cd2 | 1178 | t = ns2usecs(entry->t); |
bc0c38d1 SR |
1179 | usec_rem = do_div(t, 1000000ULL); |
1180 | secs = (unsigned long)t; | |
1181 | ||
b3806b43 SR |
1182 | ret = trace_seq_printf(s, "%16s-%-5d ", comm, entry->pid); |
1183 | if (!ret) | |
1184 | return 0; | |
1185 | ret = trace_seq_printf(s, "[%02d] ", iter->cpu); | |
1186 | if (!ret) | |
1187 | return 0; | |
1188 | ret = trace_seq_printf(s, "%5lu.%06lu: ", secs, usec_rem); | |
1189 | if (!ret) | |
1190 | return 0; | |
bc0c38d1 SR |
1191 | |
1192 | switch (entry->type) { | |
1193 | case TRACE_FN: | |
b3806b43 SR |
1194 | ret = seq_print_ip_sym(s, entry->fn.ip, sym_flags); |
1195 | if (!ret) | |
1196 | return 0; | |
bc0c38d1 SR |
1197 | if ((sym_flags & TRACE_ITER_PRINT_PARENT) && |
1198 | entry->fn.parent_ip) { | |
b3806b43 SR |
1199 | ret = trace_seq_printf(s, " <-"); |
1200 | if (!ret) | |
1201 | return 0; | |
1202 | ret = seq_print_ip_sym(s, entry->fn.parent_ip, | |
1203 | sym_flags); | |
1204 | if (!ret) | |
1205 | return 0; | |
bc0c38d1 | 1206 | } |
b3806b43 SR |
1207 | ret = trace_seq_printf(s, "\n"); |
1208 | if (!ret) | |
1209 | return 0; | |
bc0c38d1 SR |
1210 | break; |
1211 | case TRACE_CTX: | |
1212 | S = entry->ctx.prev_state < sizeof(state_to_char) ? | |
1213 | state_to_char[entry->ctx.prev_state] : 'X'; | |
b3806b43 SR |
1214 | ret = trace_seq_printf(s, " %d:%d:%c ==> %d:%d\n", |
1215 | entry->ctx.prev_pid, | |
1216 | entry->ctx.prev_prio, | |
1217 | S, | |
1218 | entry->ctx.next_pid, | |
1219 | entry->ctx.next_prio); | |
1220 | if (!ret) | |
1221 | return 0; | |
bc0c38d1 SR |
1222 | break; |
1223 | } | |
b3806b43 | 1224 | return 1; |
bc0c38d1 SR |
1225 | } |
1226 | ||
f9896bf3 IM |
1227 | static notrace int print_raw_fmt(struct trace_iterator *iter) |
1228 | { | |
1229 | struct trace_seq *s = &iter->seq; | |
1230 | struct trace_entry *entry; | |
1231 | int ret; | |
1232 | int S; | |
1233 | ||
1234 | entry = iter->ent; | |
1235 | ||
1236 | ret = trace_seq_printf(s, "%d %d %llu ", | |
1237 | entry->pid, iter->cpu, entry->t); | |
1238 | if (!ret) | |
1239 | return 0; | |
1240 | ||
1241 | switch (entry->type) { | |
1242 | case TRACE_FN: | |
1243 | ret = trace_seq_printf(s, "%x %x\n", | |
1244 | entry->fn.ip, entry->fn.parent_ip); | |
1245 | if (!ret) | |
1246 | return 0; | |
1247 | break; | |
1248 | case TRACE_CTX: | |
1249 | S = entry->ctx.prev_state < sizeof(state_to_char) ? | |
1250 | state_to_char[entry->ctx.prev_state] : 'X'; | |
1251 | ret = trace_seq_printf(s, "%d %d %c %d %d\n", | |
1252 | entry->ctx.prev_pid, | |
1253 | entry->ctx.prev_prio, | |
1254 | S, | |
1255 | entry->ctx.next_pid, | |
1256 | entry->ctx.next_prio); | |
1257 | if (!ret) | |
1258 | return 0; | |
1259 | break; | |
1260 | } | |
1261 | return 1; | |
1262 | } | |
1263 | ||
bc0c38d1 SR |
1264 | static int trace_empty(struct trace_iterator *iter) |
1265 | { | |
1266 | struct trace_array_cpu *data; | |
1267 | int cpu; | |
1268 | ||
1269 | for_each_possible_cpu(cpu) { | |
1270 | data = iter->tr->data[cpu]; | |
1271 | ||
b3806b43 SR |
1272 | if (head_page(data) && data->trace_idx && |
1273 | (data->trace_tail != data->trace_head || | |
1274 | data->trace_tail_idx != data->trace_head_idx)) | |
bc0c38d1 SR |
1275 | return 0; |
1276 | } | |
1277 | return 1; | |
1278 | } | |
1279 | ||
f9896bf3 IM |
1280 | static int print_trace_line(struct trace_iterator *iter) |
1281 | { | |
1282 | if (trace_flags & TRACE_ITER_RAW) | |
1283 | return print_raw_fmt(iter); | |
1284 | ||
1285 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) | |
1286 | return print_lat_fmt(iter, iter->idx, iter->cpu); | |
1287 | ||
1288 | return print_trace_fmt(iter); | |
1289 | } | |
1290 | ||
bc0c38d1 SR |
1291 | static int s_show(struct seq_file *m, void *v) |
1292 | { | |
1293 | struct trace_iterator *iter = v; | |
1294 | ||
1295 | if (iter->ent == NULL) { | |
1296 | if (iter->tr) { | |
1297 | seq_printf(m, "# tracer: %s\n", iter->trace->name); | |
1298 | seq_puts(m, "#\n"); | |
1299 | } | |
1300 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) { | |
1301 | /* print nothing if the buffers are empty */ | |
1302 | if (trace_empty(iter)) | |
1303 | return 0; | |
1304 | print_trace_header(m, iter); | |
1305 | if (!(trace_flags & TRACE_ITER_VERBOSE)) | |
1306 | print_lat_help_header(m); | |
1307 | } else { | |
1308 | if (!(trace_flags & TRACE_ITER_VERBOSE)) | |
1309 | print_func_help_header(m); | |
1310 | } | |
1311 | } else { | |
f9896bf3 | 1312 | print_trace_line(iter); |
214023c3 | 1313 | trace_print_seq(m, &iter->seq); |
bc0c38d1 SR |
1314 | } |
1315 | ||
1316 | return 0; | |
1317 | } | |
1318 | ||
1319 | static struct seq_operations tracer_seq_ops = { | |
4bf39a94 IM |
1320 | .start = s_start, |
1321 | .next = s_next, | |
1322 | .stop = s_stop, | |
1323 | .show = s_show, | |
bc0c38d1 SR |
1324 | }; |
1325 | ||
1326 | static struct trace_iterator notrace * | |
1327 | __tracing_open(struct inode *inode, struct file *file, int *ret) | |
1328 | { | |
1329 | struct trace_iterator *iter; | |
1330 | ||
60a11774 SR |
1331 | if (tracing_disabled) { |
1332 | *ret = -ENODEV; | |
1333 | return NULL; | |
1334 | } | |
1335 | ||
bc0c38d1 SR |
1336 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); |
1337 | if (!iter) { | |
1338 | *ret = -ENOMEM; | |
1339 | goto out; | |
1340 | } | |
1341 | ||
1342 | mutex_lock(&trace_types_lock); | |
1343 | if (current_trace && current_trace->print_max) | |
1344 | iter->tr = &max_tr; | |
1345 | else | |
1346 | iter->tr = inode->i_private; | |
1347 | iter->trace = current_trace; | |
1348 | iter->pos = -1; | |
1349 | ||
1350 | /* TODO stop tracer */ | |
1351 | *ret = seq_open(file, &tracer_seq_ops); | |
1352 | if (!*ret) { | |
1353 | struct seq_file *m = file->private_data; | |
1354 | m->private = iter; | |
1355 | ||
1356 | /* stop the trace while dumping */ | |
1357 | if (iter->tr->ctrl) | |
1358 | tracer_enabled = 0; | |
1359 | ||
1360 | if (iter->trace && iter->trace->open) | |
1361 | iter->trace->open(iter); | |
1362 | } else { | |
1363 | kfree(iter); | |
1364 | iter = NULL; | |
1365 | } | |
1366 | mutex_unlock(&trace_types_lock); | |
1367 | ||
1368 | out: | |
1369 | return iter; | |
1370 | } | |
1371 | ||
1372 | int tracing_open_generic(struct inode *inode, struct file *filp) | |
1373 | { | |
60a11774 SR |
1374 | if (tracing_disabled) |
1375 | return -ENODEV; | |
1376 | ||
bc0c38d1 SR |
1377 | filp->private_data = inode->i_private; |
1378 | return 0; | |
1379 | } | |
1380 | ||
1381 | int tracing_release(struct inode *inode, struct file *file) | |
1382 | { | |
1383 | struct seq_file *m = (struct seq_file *)file->private_data; | |
1384 | struct trace_iterator *iter = m->private; | |
1385 | ||
1386 | mutex_lock(&trace_types_lock); | |
1387 | if (iter->trace && iter->trace->close) | |
1388 | iter->trace->close(iter); | |
1389 | ||
1390 | /* reenable tracing if it was previously enabled */ | |
1391 | if (iter->tr->ctrl) | |
1392 | tracer_enabled = 1; | |
1393 | mutex_unlock(&trace_types_lock); | |
1394 | ||
1395 | seq_release(inode, file); | |
1396 | kfree(iter); | |
1397 | return 0; | |
1398 | } | |
1399 | ||
1400 | static int tracing_open(struct inode *inode, struct file *file) | |
1401 | { | |
1402 | int ret; | |
1403 | ||
1404 | __tracing_open(inode, file, &ret); | |
1405 | ||
1406 | return ret; | |
1407 | } | |
1408 | ||
1409 | static int tracing_lt_open(struct inode *inode, struct file *file) | |
1410 | { | |
1411 | struct trace_iterator *iter; | |
1412 | int ret; | |
1413 | ||
1414 | iter = __tracing_open(inode, file, &ret); | |
1415 | ||
1416 | if (!ret) | |
1417 | iter->iter_flags |= TRACE_FILE_LAT_FMT; | |
1418 | ||
1419 | return ret; | |
1420 | } | |
1421 | ||
1422 | ||
4e3c3333 | 1423 | static notrace void * |
bc0c38d1 SR |
1424 | t_next(struct seq_file *m, void *v, loff_t *pos) |
1425 | { | |
1426 | struct tracer *t = m->private; | |
1427 | ||
1428 | (*pos)++; | |
1429 | ||
1430 | if (t) | |
1431 | t = t->next; | |
1432 | ||
1433 | m->private = t; | |
1434 | ||
1435 | return t; | |
1436 | } | |
1437 | ||
1438 | static void *t_start(struct seq_file *m, loff_t *pos) | |
1439 | { | |
1440 | struct tracer *t = m->private; | |
1441 | loff_t l = 0; | |
1442 | ||
1443 | mutex_lock(&trace_types_lock); | |
1444 | for (; t && l < *pos; t = t_next(m, t, &l)) | |
1445 | ; | |
1446 | ||
1447 | return t; | |
1448 | } | |
1449 | ||
1450 | static void t_stop(struct seq_file *m, void *p) | |
1451 | { | |
1452 | mutex_unlock(&trace_types_lock); | |
1453 | } | |
1454 | ||
1455 | static int t_show(struct seq_file *m, void *v) | |
1456 | { | |
1457 | struct tracer *t = v; | |
1458 | ||
1459 | if (!t) | |
1460 | return 0; | |
1461 | ||
1462 | seq_printf(m, "%s", t->name); | |
1463 | if (t->next) | |
1464 | seq_putc(m, ' '); | |
1465 | else | |
1466 | seq_putc(m, '\n'); | |
1467 | ||
1468 | return 0; | |
1469 | } | |
1470 | ||
1471 | static struct seq_operations show_traces_seq_ops = { | |
4bf39a94 IM |
1472 | .start = t_start, |
1473 | .next = t_next, | |
1474 | .stop = t_stop, | |
1475 | .show = t_show, | |
bc0c38d1 SR |
1476 | }; |
1477 | ||
1478 | static int show_traces_open(struct inode *inode, struct file *file) | |
1479 | { | |
1480 | int ret; | |
1481 | ||
60a11774 SR |
1482 | if (tracing_disabled) |
1483 | return -ENODEV; | |
1484 | ||
bc0c38d1 SR |
1485 | ret = seq_open(file, &show_traces_seq_ops); |
1486 | if (!ret) { | |
1487 | struct seq_file *m = file->private_data; | |
1488 | m->private = trace_types; | |
1489 | } | |
1490 | ||
1491 | return ret; | |
1492 | } | |
1493 | ||
1494 | static struct file_operations tracing_fops = { | |
4bf39a94 IM |
1495 | .open = tracing_open, |
1496 | .read = seq_read, | |
1497 | .llseek = seq_lseek, | |
1498 | .release = tracing_release, | |
bc0c38d1 SR |
1499 | }; |
1500 | ||
1501 | static struct file_operations tracing_lt_fops = { | |
4bf39a94 IM |
1502 | .open = tracing_lt_open, |
1503 | .read = seq_read, | |
1504 | .llseek = seq_lseek, | |
1505 | .release = tracing_release, | |
bc0c38d1 SR |
1506 | }; |
1507 | ||
1508 | static struct file_operations show_traces_fops = { | |
1509 | .open = show_traces_open, | |
1510 | .read = seq_read, | |
1511 | .release = seq_release, | |
1512 | }; | |
1513 | ||
1514 | static ssize_t | |
1515 | tracing_iter_ctrl_read(struct file *filp, char __user *ubuf, | |
1516 | size_t cnt, loff_t *ppos) | |
1517 | { | |
1518 | char *buf; | |
1519 | int r = 0; | |
1520 | int len = 0; | |
1521 | int i; | |
1522 | ||
1523 | /* calulate max size */ | |
1524 | for (i = 0; trace_options[i]; i++) { | |
1525 | len += strlen(trace_options[i]); | |
1526 | len += 3; /* "no" and space */ | |
1527 | } | |
1528 | ||
1529 | /* +2 for \n and \0 */ | |
1530 | buf = kmalloc(len + 2, GFP_KERNEL); | |
1531 | if (!buf) | |
1532 | return -ENOMEM; | |
1533 | ||
1534 | for (i = 0; trace_options[i]; i++) { | |
1535 | if (trace_flags & (1 << i)) | |
1536 | r += sprintf(buf + r, "%s ", trace_options[i]); | |
1537 | else | |
1538 | r += sprintf(buf + r, "no%s ", trace_options[i]); | |
1539 | } | |
1540 | ||
1541 | r += sprintf(buf + r, "\n"); | |
1542 | WARN_ON(r >= len + 2); | |
1543 | ||
1544 | r = simple_read_from_buffer(ubuf, cnt, ppos, | |
1545 | buf, r); | |
1546 | ||
1547 | kfree(buf); | |
1548 | ||
1549 | return r; | |
1550 | } | |
1551 | ||
1552 | static ssize_t | |
1553 | tracing_iter_ctrl_write(struct file *filp, const char __user *ubuf, | |
1554 | size_t cnt, loff_t *ppos) | |
1555 | { | |
1556 | char buf[64]; | |
1557 | char *cmp = buf; | |
1558 | int neg = 0; | |
1559 | int i; | |
1560 | ||
1561 | if (cnt > 63) | |
1562 | cnt = 63; | |
1563 | ||
1564 | if (copy_from_user(&buf, ubuf, cnt)) | |
1565 | return -EFAULT; | |
1566 | ||
1567 | buf[cnt] = 0; | |
1568 | ||
1569 | if (strncmp(buf, "no", 2) == 0) { | |
1570 | neg = 1; | |
1571 | cmp += 2; | |
1572 | } | |
1573 | ||
1574 | for (i = 0; trace_options[i]; i++) { | |
1575 | int len = strlen(trace_options[i]); | |
1576 | ||
1577 | if (strncmp(cmp, trace_options[i], len) == 0) { | |
1578 | if (neg) | |
1579 | trace_flags &= ~(1 << i); | |
1580 | else | |
1581 | trace_flags |= (1 << i); | |
1582 | break; | |
1583 | } | |
1584 | } | |
1585 | ||
1586 | filp->f_pos += cnt; | |
1587 | ||
1588 | return cnt; | |
1589 | } | |
1590 | ||
1591 | static struct file_operations tracing_iter_fops = { | |
1592 | .open = tracing_open_generic, | |
1593 | .read = tracing_iter_ctrl_read, | |
1594 | .write = tracing_iter_ctrl_write, | |
1595 | }; | |
1596 | ||
7bd2f24c IM |
1597 | static const char readme_msg[] = |
1598 | "tracing mini-HOWTO:\n\n" | |
1599 | "# mkdir /debug\n" | |
1600 | "# mount -t debugfs nodev /debug\n\n" | |
1601 | "# cat /debug/tracing/available_tracers\n" | |
1602 | "wakeup preemptirqsoff preemptoff irqsoff ftrace sched_switch none\n\n" | |
1603 | "# cat /debug/tracing/current_tracer\n" | |
1604 | "none\n" | |
1605 | "# echo sched_switch > /debug/tracing/current_tracer\n" | |
1606 | "# cat /debug/tracing/current_tracer\n" | |
1607 | "sched_switch\n" | |
1608 | "# cat /debug/tracing/iter_ctrl\n" | |
1609 | "noprint-parent nosym-offset nosym-addr noverbose\n" | |
1610 | "# echo print-parent > /debug/tracing/iter_ctrl\n" | |
1611 | "# echo 1 > /debug/tracing/tracing_enabled\n" | |
1612 | "# cat /debug/tracing/trace > /tmp/trace.txt\n" | |
1613 | "echo 0 > /debug/tracing/tracing_enabled\n" | |
1614 | ; | |
1615 | ||
1616 | static ssize_t | |
1617 | tracing_readme_read(struct file *filp, char __user *ubuf, | |
1618 | size_t cnt, loff_t *ppos) | |
1619 | { | |
1620 | return simple_read_from_buffer(ubuf, cnt, ppos, | |
1621 | readme_msg, strlen(readme_msg)); | |
1622 | } | |
1623 | ||
1624 | static struct file_operations tracing_readme_fops = { | |
1625 | .open = tracing_open_generic, | |
1626 | .read = tracing_readme_read, | |
1627 | }; | |
1628 | ||
1629 | ||
bc0c38d1 SR |
1630 | static ssize_t |
1631 | tracing_ctrl_read(struct file *filp, char __user *ubuf, | |
1632 | size_t cnt, loff_t *ppos) | |
1633 | { | |
1634 | struct trace_array *tr = filp->private_data; | |
1635 | char buf[64]; | |
1636 | int r; | |
1637 | ||
1638 | r = sprintf(buf, "%ld\n", tr->ctrl); | |
4e3c3333 | 1639 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
1640 | } |
1641 | ||
1642 | static ssize_t | |
1643 | tracing_ctrl_write(struct file *filp, const char __user *ubuf, | |
1644 | size_t cnt, loff_t *ppos) | |
1645 | { | |
1646 | struct trace_array *tr = filp->private_data; | |
1647 | long val; | |
1648 | char buf[64]; | |
1649 | ||
1650 | if (cnt > 63) | |
1651 | cnt = 63; | |
1652 | ||
1653 | if (copy_from_user(&buf, ubuf, cnt)) | |
1654 | return -EFAULT; | |
1655 | ||
1656 | buf[cnt] = 0; | |
1657 | ||
1658 | val = simple_strtoul(buf, NULL, 10); | |
1659 | ||
1660 | val = !!val; | |
1661 | ||
1662 | mutex_lock(&trace_types_lock); | |
1663 | if (tr->ctrl ^ val) { | |
1664 | if (val) | |
1665 | tracer_enabled = 1; | |
1666 | else | |
1667 | tracer_enabled = 0; | |
1668 | ||
1669 | tr->ctrl = val; | |
1670 | ||
1671 | if (current_trace && current_trace->ctrl_update) | |
1672 | current_trace->ctrl_update(tr); | |
1673 | } | |
1674 | mutex_unlock(&trace_types_lock); | |
1675 | ||
1676 | filp->f_pos += cnt; | |
1677 | ||
1678 | return cnt; | |
1679 | } | |
1680 | ||
1681 | static ssize_t | |
1682 | tracing_set_trace_read(struct file *filp, char __user *ubuf, | |
1683 | size_t cnt, loff_t *ppos) | |
1684 | { | |
1685 | char buf[max_tracer_type_len+2]; | |
1686 | int r; | |
1687 | ||
1688 | mutex_lock(&trace_types_lock); | |
1689 | if (current_trace) | |
1690 | r = sprintf(buf, "%s\n", current_trace->name); | |
1691 | else | |
1692 | r = sprintf(buf, "\n"); | |
1693 | mutex_unlock(&trace_types_lock); | |
1694 | ||
4bf39a94 | 1695 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
1696 | } |
1697 | ||
1698 | static ssize_t | |
1699 | tracing_set_trace_write(struct file *filp, const char __user *ubuf, | |
1700 | size_t cnt, loff_t *ppos) | |
1701 | { | |
1702 | struct trace_array *tr = &global_trace; | |
1703 | struct tracer *t; | |
1704 | char buf[max_tracer_type_len+1]; | |
1705 | int i; | |
1706 | ||
1707 | if (cnt > max_tracer_type_len) | |
1708 | cnt = max_tracer_type_len; | |
1709 | ||
1710 | if (copy_from_user(&buf, ubuf, cnt)) | |
1711 | return -EFAULT; | |
1712 | ||
1713 | buf[cnt] = 0; | |
1714 | ||
1715 | /* strip ending whitespace. */ | |
1716 | for (i = cnt - 1; i > 0 && isspace(buf[i]); i--) | |
1717 | buf[i] = 0; | |
1718 | ||
1719 | mutex_lock(&trace_types_lock); | |
1720 | for (t = trace_types; t; t = t->next) { | |
1721 | if (strcmp(t->name, buf) == 0) | |
1722 | break; | |
1723 | } | |
1724 | if (!t || t == current_trace) | |
1725 | goto out; | |
1726 | ||
1727 | if (current_trace && current_trace->reset) | |
1728 | current_trace->reset(tr); | |
1729 | ||
1730 | current_trace = t; | |
1731 | if (t->init) | |
1732 | t->init(tr); | |
1733 | ||
1734 | out: | |
1735 | mutex_unlock(&trace_types_lock); | |
1736 | ||
1737 | filp->f_pos += cnt; | |
1738 | ||
1739 | return cnt; | |
1740 | } | |
1741 | ||
1742 | static ssize_t | |
1743 | tracing_max_lat_read(struct file *filp, char __user *ubuf, | |
1744 | size_t cnt, loff_t *ppos) | |
1745 | { | |
1746 | unsigned long *ptr = filp->private_data; | |
1747 | char buf[64]; | |
1748 | int r; | |
1749 | ||
1750 | r = snprintf(buf, 64, "%ld\n", | |
1751 | *ptr == (unsigned long)-1 ? -1 : nsecs_to_usecs(*ptr)); | |
1752 | if (r > 64) | |
1753 | r = 64; | |
4bf39a94 | 1754 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
1755 | } |
1756 | ||
1757 | static ssize_t | |
1758 | tracing_max_lat_write(struct file *filp, const char __user *ubuf, | |
1759 | size_t cnt, loff_t *ppos) | |
1760 | { | |
1761 | long *ptr = filp->private_data; | |
1762 | long val; | |
1763 | char buf[64]; | |
1764 | ||
1765 | if (cnt > 63) | |
1766 | cnt = 63; | |
1767 | ||
1768 | if (copy_from_user(&buf, ubuf, cnt)) | |
1769 | return -EFAULT; | |
1770 | ||
1771 | buf[cnt] = 0; | |
1772 | ||
1773 | val = simple_strtoul(buf, NULL, 10); | |
1774 | ||
1775 | *ptr = val * 1000; | |
1776 | ||
1777 | return cnt; | |
1778 | } | |
1779 | ||
b3806b43 SR |
1780 | static atomic_t tracing_reader; |
1781 | ||
1782 | static int tracing_open_pipe(struct inode *inode, struct file *filp) | |
1783 | { | |
1784 | struct trace_iterator *iter; | |
1785 | ||
1786 | if (tracing_disabled) | |
1787 | return -ENODEV; | |
1788 | ||
1789 | /* We only allow for reader of the pipe */ | |
1790 | if (atomic_inc_return(&tracing_reader) != 1) { | |
1791 | atomic_dec(&tracing_reader); | |
1792 | return -EBUSY; | |
1793 | } | |
1794 | ||
1795 | /* create a buffer to store the information to pass to userspace */ | |
1796 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); | |
1797 | if (!iter) | |
1798 | return -ENOMEM; | |
1799 | ||
1800 | iter->tr = &global_trace; | |
1801 | ||
1802 | filp->private_data = iter; | |
1803 | ||
1804 | return 0; | |
1805 | } | |
1806 | ||
1807 | static int tracing_release_pipe(struct inode *inode, struct file *file) | |
1808 | { | |
1809 | struct trace_iterator *iter = file->private_data; | |
1810 | ||
1811 | kfree(iter); | |
1812 | atomic_dec(&tracing_reader); | |
1813 | ||
1814 | return 0; | |
1815 | } | |
1816 | ||
1817 | /* | |
1818 | * Consumer reader. | |
1819 | */ | |
1820 | static ssize_t | |
1821 | tracing_read_pipe(struct file *filp, char __user *ubuf, | |
1822 | size_t cnt, loff_t *ppos) | |
1823 | { | |
1824 | struct trace_iterator *iter = filp->private_data; | |
1825 | struct trace_array_cpu *data; | |
1826 | static cpumask_t mask; | |
1827 | struct trace_entry *entry; | |
1828 | static int start; | |
1829 | unsigned long flags; | |
1830 | int read = 0; | |
1831 | int cpu; | |
1832 | int len; | |
1833 | int ret; | |
1834 | ||
1835 | /* return any leftover data */ | |
1836 | if (iter->seq.len > start) { | |
1837 | len = iter->seq.len - start; | |
1838 | if (cnt > len) | |
1839 | cnt = len; | |
1840 | ret = copy_to_user(ubuf, iter->seq.buffer + start, cnt); | |
1841 | if (ret) | |
1842 | cnt = -EFAULT; | |
1843 | ||
1844 | start += len; | |
1845 | ||
1846 | return cnt; | |
1847 | } | |
1848 | ||
1849 | trace_seq_reset(&iter->seq); | |
1850 | start = 0; | |
1851 | ||
1852 | while (trace_empty(iter)) { | |
1853 | /* | |
1854 | * This is a make-shift waitqueue. The reason we don't use | |
1855 | * an actual wait queue is because: | |
1856 | * 1) we only ever have one waiter | |
1857 | * 2) the tracing, traces all functions, we don't want | |
1858 | * the overhead of calling wake_up and friends | |
1859 | * (and tracing them too) | |
1860 | * Anyway, this is really very primitive wakeup. | |
1861 | */ | |
1862 | set_current_state(TASK_INTERRUPTIBLE); | |
1863 | iter->tr->waiter = current; | |
1864 | ||
1865 | /* sleep for one second, and try again. */ | |
1866 | schedule_timeout(HZ); | |
1867 | ||
1868 | iter->tr->waiter = NULL; | |
1869 | ||
1870 | if (signal_pending(current)) | |
1871 | return -EINTR; | |
1872 | ||
1873 | /* | |
1874 | * We block until we read something and tracing is disabled. | |
1875 | * We still block if tracing is disabled, but we have never | |
1876 | * read anything. This allows a user to cat this file, and | |
1877 | * then enable tracing. But after we have read something, | |
1878 | * we give an EOF when tracing is again disabled. | |
1879 | * | |
1880 | * iter->pos will be 0 if we haven't read anything. | |
1881 | */ | |
1882 | if (!tracer_enabled && iter->pos) | |
1883 | break; | |
1884 | ||
1885 | continue; | |
1886 | } | |
1887 | ||
1888 | /* stop when tracing is finished */ | |
1889 | if (trace_empty(iter)) | |
1890 | return 0; | |
1891 | ||
1892 | if (cnt >= PAGE_SIZE) | |
1893 | cnt = PAGE_SIZE - 1; | |
1894 | ||
1895 | memset(iter, 0, sizeof(*iter)); | |
1896 | iter->tr = &global_trace; | |
1897 | iter->pos = -1; | |
1898 | ||
1899 | /* | |
1900 | * We need to stop all tracing on all CPUS to read the | |
1901 | * the next buffer. This is a bit expensive, but is | |
1902 | * not done often. We fill all what we can read, | |
1903 | * and then release the locks again. | |
1904 | */ | |
1905 | ||
1906 | cpus_clear(mask); | |
1907 | local_irq_save(flags); | |
1908 | for_each_possible_cpu(cpu) { | |
1909 | data = iter->tr->data[cpu]; | |
1910 | ||
1911 | if (!head_page(data) || !data->trace_idx) | |
1912 | continue; | |
1913 | ||
1914 | atomic_inc(&data->disabled); | |
1915 | spin_lock(&data->lock); | |
1916 | cpu_set(cpu, mask); | |
1917 | } | |
1918 | ||
8c523a9d | 1919 | while ((entry = find_next_entry_inc(iter)) != NULL) { |
f9896bf3 | 1920 | ret = print_trace_line(iter); |
b3806b43 SR |
1921 | if (!ret) |
1922 | break; | |
1923 | ||
1924 | trace_consume(iter); | |
1925 | ||
1926 | if (iter->seq.len >= cnt) | |
1927 | break; | |
b3806b43 SR |
1928 | } |
1929 | ||
d4c5a2f5 | 1930 | for_each_cpu_mask(cpu, mask) { |
b3806b43 | 1931 | data = iter->tr->data[cpu]; |
b3806b43 SR |
1932 | spin_unlock(&data->lock); |
1933 | atomic_dec(&data->disabled); | |
1934 | } | |
1935 | local_irq_restore(flags); | |
1936 | ||
1937 | /* Now copy what we have to the user */ | |
1938 | read = iter->seq.len; | |
1939 | if (read > cnt) | |
1940 | read = cnt; | |
1941 | ||
1942 | ret = copy_to_user(ubuf, iter->seq.buffer, read); | |
1943 | ||
1944 | if (read < iter->seq.len) | |
1945 | start = read; | |
1946 | else | |
1947 | trace_seq_reset(&iter->seq); | |
1948 | ||
1949 | if (ret) | |
1950 | read = -EFAULT; | |
1951 | ||
1952 | return read; | |
1953 | } | |
1954 | ||
bc0c38d1 | 1955 | static struct file_operations tracing_max_lat_fops = { |
4bf39a94 IM |
1956 | .open = tracing_open_generic, |
1957 | .read = tracing_max_lat_read, | |
1958 | .write = tracing_max_lat_write, | |
bc0c38d1 SR |
1959 | }; |
1960 | ||
1961 | static struct file_operations tracing_ctrl_fops = { | |
4bf39a94 IM |
1962 | .open = tracing_open_generic, |
1963 | .read = tracing_ctrl_read, | |
1964 | .write = tracing_ctrl_write, | |
bc0c38d1 SR |
1965 | }; |
1966 | ||
1967 | static struct file_operations set_tracer_fops = { | |
4bf39a94 IM |
1968 | .open = tracing_open_generic, |
1969 | .read = tracing_set_trace_read, | |
1970 | .write = tracing_set_trace_write, | |
bc0c38d1 SR |
1971 | }; |
1972 | ||
b3806b43 | 1973 | static struct file_operations tracing_pipe_fops = { |
4bf39a94 IM |
1974 | .open = tracing_open_pipe, |
1975 | .read = tracing_read_pipe, | |
1976 | .release = tracing_release_pipe, | |
b3806b43 SR |
1977 | }; |
1978 | ||
bc0c38d1 SR |
1979 | #ifdef CONFIG_DYNAMIC_FTRACE |
1980 | ||
1981 | static ssize_t | |
1982 | tracing_read_long(struct file *filp, char __user *ubuf, | |
1983 | size_t cnt, loff_t *ppos) | |
1984 | { | |
1985 | unsigned long *p = filp->private_data; | |
1986 | char buf[64]; | |
1987 | int r; | |
1988 | ||
1989 | r = sprintf(buf, "%ld\n", *p); | |
4bf39a94 IM |
1990 | |
1991 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
bc0c38d1 SR |
1992 | } |
1993 | ||
1994 | static struct file_operations tracing_read_long_fops = { | |
4bf39a94 IM |
1995 | .open = tracing_open_generic, |
1996 | .read = tracing_read_long, | |
bc0c38d1 SR |
1997 | }; |
1998 | #endif | |
1999 | ||
2000 | static struct dentry *d_tracer; | |
2001 | ||
2002 | struct dentry *tracing_init_dentry(void) | |
2003 | { | |
2004 | static int once; | |
2005 | ||
2006 | if (d_tracer) | |
2007 | return d_tracer; | |
2008 | ||
2009 | d_tracer = debugfs_create_dir("tracing", NULL); | |
2010 | ||
2011 | if (!d_tracer && !once) { | |
2012 | once = 1; | |
2013 | pr_warning("Could not create debugfs directory 'tracing'\n"); | |
2014 | return NULL; | |
2015 | } | |
2016 | ||
2017 | return d_tracer; | |
2018 | } | |
2019 | ||
60a11774 SR |
2020 | #ifdef CONFIG_FTRACE_SELFTEST |
2021 | /* Let selftest have access to static functions in this file */ | |
2022 | #include "trace_selftest.c" | |
2023 | #endif | |
2024 | ||
bc0c38d1 SR |
2025 | static __init void tracer_init_debugfs(void) |
2026 | { | |
2027 | struct dentry *d_tracer; | |
2028 | struct dentry *entry; | |
2029 | ||
2030 | d_tracer = tracing_init_dentry(); | |
2031 | ||
2032 | entry = debugfs_create_file("tracing_enabled", 0644, d_tracer, | |
2033 | &global_trace, &tracing_ctrl_fops); | |
2034 | if (!entry) | |
2035 | pr_warning("Could not create debugfs 'tracing_enabled' entry\n"); | |
2036 | ||
2037 | entry = debugfs_create_file("iter_ctrl", 0644, d_tracer, | |
2038 | NULL, &tracing_iter_fops); | |
2039 | if (!entry) | |
2040 | pr_warning("Could not create debugfs 'iter_ctrl' entry\n"); | |
2041 | ||
2042 | entry = debugfs_create_file("latency_trace", 0444, d_tracer, | |
2043 | &global_trace, &tracing_lt_fops); | |
2044 | if (!entry) | |
2045 | pr_warning("Could not create debugfs 'latency_trace' entry\n"); | |
2046 | ||
2047 | entry = debugfs_create_file("trace", 0444, d_tracer, | |
2048 | &global_trace, &tracing_fops); | |
2049 | if (!entry) | |
2050 | pr_warning("Could not create debugfs 'trace' entry\n"); | |
2051 | ||
2052 | entry = debugfs_create_file("available_tracers", 0444, d_tracer, | |
2053 | &global_trace, &show_traces_fops); | |
2054 | if (!entry) | |
2055 | pr_warning("Could not create debugfs 'trace' entry\n"); | |
2056 | ||
2057 | entry = debugfs_create_file("current_tracer", 0444, d_tracer, | |
2058 | &global_trace, &set_tracer_fops); | |
2059 | if (!entry) | |
2060 | pr_warning("Could not create debugfs 'trace' entry\n"); | |
2061 | ||
2062 | entry = debugfs_create_file("tracing_max_latency", 0644, d_tracer, | |
2063 | &tracing_max_latency, | |
2064 | &tracing_max_lat_fops); | |
2065 | if (!entry) | |
2066 | pr_warning("Could not create debugfs " | |
2067 | "'tracing_max_latency' entry\n"); | |
2068 | ||
2069 | entry = debugfs_create_file("tracing_thresh", 0644, d_tracer, | |
2070 | &tracing_thresh, &tracing_max_lat_fops); | |
2071 | if (!entry) | |
2072 | pr_warning("Could not create debugfs " | |
2073 | "'tracing_threash' entry\n"); | |
7bd2f24c IM |
2074 | entry = debugfs_create_file("README", 0644, d_tracer, |
2075 | NULL, &tracing_readme_fops); | |
2076 | if (!entry) | |
2077 | pr_warning("Could not create debugfs 'README' entry\n"); | |
2078 | ||
b3806b43 SR |
2079 | entry = debugfs_create_file("trace_pipe", 0644, d_tracer, |
2080 | NULL, &tracing_pipe_fops); | |
2081 | if (!entry) | |
2082 | pr_warning("Could not create debugfs " | |
2083 | "'tracing_threash' entry\n"); | |
bc0c38d1 SR |
2084 | |
2085 | #ifdef CONFIG_DYNAMIC_FTRACE | |
2086 | entry = debugfs_create_file("dyn_ftrace_total_info", 0444, d_tracer, | |
2087 | &ftrace_update_tot_cnt, | |
2088 | &tracing_read_long_fops); | |
2089 | if (!entry) | |
2090 | pr_warning("Could not create debugfs " | |
2091 | "'dyn_ftrace_total_info' entry\n"); | |
2092 | #endif | |
2093 | } | |
2094 | ||
2095 | /* dummy trace to disable tracing */ | |
2096 | static struct tracer no_tracer __read_mostly = | |
2097 | { | |
4bf39a94 | 2098 | .name = "none", |
bc0c38d1 SR |
2099 | }; |
2100 | ||
4c11d7ae | 2101 | static int trace_alloc_page(void) |
bc0c38d1 | 2102 | { |
4c11d7ae | 2103 | struct trace_array_cpu *data; |
4c11d7ae SR |
2104 | struct page *page, *tmp; |
2105 | LIST_HEAD(pages); | |
c7aafc54 | 2106 | void *array; |
4c11d7ae SR |
2107 | int i; |
2108 | ||
2109 | /* first allocate a page for each CPU */ | |
2110 | for_each_possible_cpu(i) { | |
2111 | array = (void *)__get_free_page(GFP_KERNEL); | |
2112 | if (array == NULL) { | |
2113 | printk(KERN_ERR "tracer: failed to allocate page" | |
2114 | "for trace buffer!\n"); | |
2115 | goto free_pages; | |
2116 | } | |
2117 | ||
2118 | page = virt_to_page(array); | |
2119 | list_add(&page->lru, &pages); | |
2120 | ||
2121 | /* Only allocate if we are actually using the max trace */ | |
2122 | #ifdef CONFIG_TRACER_MAX_TRACE | |
2123 | array = (void *)__get_free_page(GFP_KERNEL); | |
2124 | if (array == NULL) { | |
2125 | printk(KERN_ERR "tracer: failed to allocate page" | |
2126 | "for trace buffer!\n"); | |
2127 | goto free_pages; | |
2128 | } | |
2129 | page = virt_to_page(array); | |
2130 | list_add(&page->lru, &pages); | |
2131 | #endif | |
2132 | } | |
2133 | ||
2134 | /* Now that we successfully allocate a page per CPU, add them */ | |
2135 | for_each_possible_cpu(i) { | |
2136 | data = global_trace.data[i]; | |
b3806b43 | 2137 | spin_lock_init(&data->lock); |
d4c5a2f5 | 2138 | lockdep_set_class(&data->lock, &data->lock_key); |
4c11d7ae | 2139 | page = list_entry(pages.next, struct page, lru); |
c7aafc54 | 2140 | list_del_init(&page->lru); |
4c11d7ae SR |
2141 | list_add_tail(&page->lru, &data->trace_pages); |
2142 | ClearPageLRU(page); | |
2143 | ||
2144 | #ifdef CONFIG_TRACER_MAX_TRACE | |
2145 | data = max_tr.data[i]; | |
b3806b43 | 2146 | spin_lock_init(&data->lock); |
d4c5a2f5 | 2147 | lockdep_set_class(&data->lock, &data->lock_key); |
4c11d7ae | 2148 | page = list_entry(pages.next, struct page, lru); |
c7aafc54 | 2149 | list_del_init(&page->lru); |
4c11d7ae SR |
2150 | list_add_tail(&page->lru, &data->trace_pages); |
2151 | SetPageLRU(page); | |
2152 | #endif | |
2153 | } | |
2154 | global_trace.entries += ENTRIES_PER_PAGE; | |
2155 | ||
2156 | return 0; | |
2157 | ||
2158 | free_pages: | |
2159 | list_for_each_entry_safe(page, tmp, &pages, lru) { | |
c7aafc54 | 2160 | list_del_init(&page->lru); |
4c11d7ae SR |
2161 | __free_page(page); |
2162 | } | |
2163 | return -ENOMEM; | |
bc0c38d1 SR |
2164 | } |
2165 | ||
2166 | __init static int tracer_alloc_buffers(void) | |
2167 | { | |
4c11d7ae SR |
2168 | struct trace_array_cpu *data; |
2169 | void *array; | |
2170 | struct page *page; | |
2171 | int pages = 0; | |
60a11774 | 2172 | int ret = -ENOMEM; |
bc0c38d1 SR |
2173 | int i; |
2174 | ||
4c11d7ae | 2175 | /* Allocate the first page for all buffers */ |
bc0c38d1 | 2176 | for_each_possible_cpu(i) { |
4c11d7ae | 2177 | data = global_trace.data[i] = &per_cpu(global_trace_cpu, i); |
bc0c38d1 SR |
2178 | max_tr.data[i] = &per_cpu(max_data, i); |
2179 | ||
4c11d7ae | 2180 | array = (void *)__get_free_page(GFP_KERNEL); |
bc0c38d1 | 2181 | if (array == NULL) { |
4c11d7ae SR |
2182 | printk(KERN_ERR "tracer: failed to allocate page" |
2183 | "for trace buffer!\n"); | |
bc0c38d1 SR |
2184 | goto free_buffers; |
2185 | } | |
4c11d7ae SR |
2186 | |
2187 | /* set the array to the list */ | |
2188 | INIT_LIST_HEAD(&data->trace_pages); | |
2189 | page = virt_to_page(array); | |
2190 | list_add(&page->lru, &data->trace_pages); | |
2191 | /* use the LRU flag to differentiate the two buffers */ | |
2192 | ClearPageLRU(page); | |
bc0c38d1 SR |
2193 | |
2194 | /* Only allocate if we are actually using the max trace */ | |
2195 | #ifdef CONFIG_TRACER_MAX_TRACE | |
4c11d7ae | 2196 | array = (void *)__get_free_page(GFP_KERNEL); |
bc0c38d1 | 2197 | if (array == NULL) { |
4c11d7ae SR |
2198 | printk(KERN_ERR "tracer: failed to allocate page" |
2199 | "for trace buffer!\n"); | |
bc0c38d1 SR |
2200 | goto free_buffers; |
2201 | } | |
4c11d7ae SR |
2202 | |
2203 | INIT_LIST_HEAD(&max_tr.data[i]->trace_pages); | |
2204 | page = virt_to_page(array); | |
2205 | list_add(&page->lru, &max_tr.data[i]->trace_pages); | |
2206 | SetPageLRU(page); | |
bc0c38d1 SR |
2207 | #endif |
2208 | } | |
2209 | ||
2210 | /* | |
2211 | * Since we allocate by orders of pages, we may be able to | |
2212 | * round up a bit. | |
2213 | */ | |
4c11d7ae | 2214 | global_trace.entries = ENTRIES_PER_PAGE; |
4c11d7ae SR |
2215 | pages++; |
2216 | ||
2217 | while (global_trace.entries < trace_nr_entries) { | |
2218 | if (trace_alloc_page()) | |
2219 | break; | |
2220 | pages++; | |
2221 | } | |
89b2f978 | 2222 | max_tr.entries = global_trace.entries; |
bc0c38d1 | 2223 | |
4c11d7ae SR |
2224 | pr_info("tracer: %d pages allocated for %ld", |
2225 | pages, trace_nr_entries); | |
bc0c38d1 SR |
2226 | pr_info(" entries of %ld bytes\n", (long)TRACE_ENTRY_SIZE); |
2227 | pr_info(" actual entries %ld\n", global_trace.entries); | |
2228 | ||
2229 | tracer_init_debugfs(); | |
2230 | ||
2231 | trace_init_cmdlines(); | |
2232 | ||
2233 | register_tracer(&no_tracer); | |
2234 | current_trace = &no_tracer; | |
2235 | ||
60a11774 SR |
2236 | /* All seems OK, enable tracing */ |
2237 | tracing_disabled = 0; | |
2238 | ||
bc0c38d1 SR |
2239 | return 0; |
2240 | ||
2241 | free_buffers: | |
2242 | for (i-- ; i >= 0; i--) { | |
4c11d7ae | 2243 | struct page *page, *tmp; |
bc0c38d1 SR |
2244 | struct trace_array_cpu *data = global_trace.data[i]; |
2245 | ||
c7aafc54 | 2246 | if (data) { |
4c11d7ae SR |
2247 | list_for_each_entry_safe(page, tmp, |
2248 | &data->trace_pages, lru) { | |
c7aafc54 | 2249 | list_del_init(&page->lru); |
4c11d7ae SR |
2250 | __free_page(page); |
2251 | } | |
bc0c38d1 SR |
2252 | } |
2253 | ||
2254 | #ifdef CONFIG_TRACER_MAX_TRACE | |
2255 | data = max_tr.data[i]; | |
c7aafc54 | 2256 | if (data) { |
4c11d7ae SR |
2257 | list_for_each_entry_safe(page, tmp, |
2258 | &data->trace_pages, lru) { | |
c7aafc54 | 2259 | list_del_init(&page->lru); |
4c11d7ae SR |
2260 | __free_page(page); |
2261 | } | |
bc0c38d1 SR |
2262 | } |
2263 | #endif | |
2264 | } | |
60a11774 | 2265 | return ret; |
bc0c38d1 | 2266 | } |
60a11774 | 2267 | fs_initcall(tracer_alloc_buffers); |