Commit | Line | Data |
---|---|---|
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 | ||
750ed1a4 IM |
45 | notrace cycle_t ftrace_now(int cpu) |
46 | { | |
0fd9e0da | 47 | return cpu_clock(cpu); |
750ed1a4 IM |
48 | } |
49 | ||
bc0c38d1 SR |
50 | static struct trace_array global_trace; |
51 | ||
52 | static DEFINE_PER_CPU(struct trace_array_cpu, global_trace_cpu); | |
53 | ||
54 | static struct trace_array max_tr; | |
55 | ||
56 | static DEFINE_PER_CPU(struct trace_array_cpu, max_data); | |
57 | ||
26994ead | 58 | static int tracer_enabled = 1; |
4c11d7ae | 59 | static unsigned long trace_nr_entries = 16384UL; |
bc0c38d1 SR |
60 | |
61 | static struct tracer *trace_types __read_mostly; | |
62 | static struct tracer *current_trace __read_mostly; | |
63 | static int max_tracer_type_len; | |
64 | ||
65 | static DEFINE_MUTEX(trace_types_lock); | |
66 | ||
4c11d7ae SR |
67 | #define ENTRIES_PER_PAGE (PAGE_SIZE / sizeof(struct trace_entry)) |
68 | ||
bc0c38d1 SR |
69 | static int __init set_nr_entries(char *str) |
70 | { | |
71 | if (!str) | |
72 | return 0; | |
73 | trace_nr_entries = simple_strtoul(str, &str, 0); | |
74 | return 1; | |
75 | } | |
76 | __setup("trace_entries=", set_nr_entries); | |
77 | ||
57f50be1 SR |
78 | unsigned long nsecs_to_usecs(unsigned long nsecs) |
79 | { | |
80 | return nsecs / 1000; | |
81 | } | |
82 | ||
bc0c38d1 SR |
83 | enum trace_type { |
84 | __TRACE_FIRST_TYPE = 0, | |
85 | ||
86 | TRACE_FN, | |
87 | TRACE_CTX, | |
f0a920d5 | 88 | TRACE_SPECIAL, |
bc0c38d1 SR |
89 | |
90 | __TRACE_LAST_TYPE | |
91 | }; | |
92 | ||
93 | enum trace_flag_type { | |
94 | TRACE_FLAG_IRQS_OFF = 0x01, | |
95 | TRACE_FLAG_NEED_RESCHED = 0x02, | |
96 | TRACE_FLAG_HARDIRQ = 0x04, | |
97 | TRACE_FLAG_SOFTIRQ = 0x08, | |
98 | }; | |
99 | ||
100 | enum trace_iterator_flags { | |
101 | TRACE_ITER_PRINT_PARENT = 0x01, | |
102 | TRACE_ITER_SYM_OFFSET = 0x02, | |
103 | TRACE_ITER_SYM_ADDR = 0x04, | |
104 | TRACE_ITER_VERBOSE = 0x08, | |
f9896bf3 | 105 | TRACE_ITER_RAW = 0x10, |
cb0f12aa | 106 | TRACE_ITER_BIN = 0x20, |
bc0c38d1 SR |
107 | }; |
108 | ||
109 | #define TRACE_ITER_SYM_MASK \ | |
110 | (TRACE_ITER_PRINT_PARENT|TRACE_ITER_SYM_OFFSET|TRACE_ITER_SYM_ADDR) | |
111 | ||
112 | /* These must match the bit postions above */ | |
113 | static const char *trace_options[] = { | |
114 | "print-parent", | |
115 | "sym-offset", | |
116 | "sym-addr", | |
117 | "verbose", | |
f9896bf3 | 118 | "raw", |
cb0f12aa | 119 | "bin", |
bc0c38d1 SR |
120 | NULL |
121 | }; | |
122 | ||
123 | static unsigned trace_flags; | |
124 | ||
4c11d7ae | 125 | static DEFINE_SPINLOCK(ftrace_max_lock); |
bc0c38d1 SR |
126 | |
127 | /* | |
128 | * Copy the new maximum trace into the separate maximum-trace | |
129 | * structure. (this way the maximum trace is permanently saved, | |
130 | * for later retrieval via /debugfs/tracing/latency_trace) | |
131 | */ | |
4e3c3333 | 132 | static notrace void |
bc0c38d1 SR |
133 | __update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) |
134 | { | |
135 | struct trace_array_cpu *data = tr->data[cpu]; | |
136 | ||
137 | max_tr.cpu = cpu; | |
138 | max_tr.time_start = data->preempt_timestamp; | |
139 | ||
140 | data = max_tr.data[cpu]; | |
141 | data->saved_latency = tracing_max_latency; | |
142 | ||
143 | memcpy(data->comm, tsk->comm, TASK_COMM_LEN); | |
144 | data->pid = tsk->pid; | |
145 | data->uid = tsk->uid; | |
146 | data->nice = tsk->static_prio - 20 - MAX_RT_PRIO; | |
147 | data->policy = tsk->policy; | |
148 | data->rt_priority = tsk->rt_priority; | |
149 | ||
150 | /* record this tasks comm */ | |
151 | tracing_record_cmdline(current); | |
152 | } | |
153 | ||
c7aafc54 IM |
154 | void check_pages(struct trace_array_cpu *data) |
155 | { | |
156 | struct page *page, *tmp; | |
157 | ||
158 | BUG_ON(data->trace_pages.next->prev != &data->trace_pages); | |
159 | BUG_ON(data->trace_pages.prev->next != &data->trace_pages); | |
160 | ||
161 | list_for_each_entry_safe(page, tmp, &data->trace_pages, lru) { | |
162 | BUG_ON(page->lru.next->prev != &page->lru); | |
163 | BUG_ON(page->lru.prev->next != &page->lru); | |
164 | } | |
165 | } | |
166 | ||
167 | void *head_page(struct trace_array_cpu *data) | |
168 | { | |
169 | struct page *page; | |
170 | ||
171 | check_pages(data); | |
172 | if (list_empty(&data->trace_pages)) | |
173 | return NULL; | |
174 | ||
175 | page = list_entry(data->trace_pages.next, struct page, lru); | |
176 | BUG_ON(&page->lru == &data->trace_pages); | |
177 | ||
178 | return page_address(page); | |
179 | } | |
180 | ||
214023c3 SR |
181 | static notrace int |
182 | trace_seq_printf(struct trace_seq *s, const char *fmt, ...) | |
183 | { | |
184 | int len = (PAGE_SIZE - 1) - s->len; | |
185 | va_list ap; | |
b3806b43 | 186 | int ret; |
214023c3 SR |
187 | |
188 | if (!len) | |
189 | return 0; | |
190 | ||
191 | va_start(ap, fmt); | |
b3806b43 | 192 | ret = vsnprintf(s->buffer + s->len, len, fmt, ap); |
214023c3 SR |
193 | va_end(ap); |
194 | ||
b3806b43 SR |
195 | /* If we can't write it all, don't bother writing anything */ |
196 | if (ret > len) | |
197 | return 0; | |
198 | ||
199 | s->len += ret; | |
214023c3 SR |
200 | |
201 | return len; | |
202 | } | |
203 | ||
204 | static notrace int | |
205 | trace_seq_puts(struct trace_seq *s, const char *str) | |
206 | { | |
207 | int len = strlen(str); | |
208 | ||
209 | if (len > ((PAGE_SIZE - 1) - s->len)) | |
b3806b43 | 210 | return 0; |
214023c3 SR |
211 | |
212 | memcpy(s->buffer + s->len, str, len); | |
213 | s->len += len; | |
214 | ||
215 | return len; | |
216 | } | |
217 | ||
218 | static notrace int | |
219 | trace_seq_putc(struct trace_seq *s, unsigned char c) | |
220 | { | |
221 | if (s->len >= (PAGE_SIZE - 1)) | |
222 | return 0; | |
223 | ||
224 | s->buffer[s->len++] = c; | |
225 | ||
226 | return 1; | |
227 | } | |
228 | ||
cb0f12aa IM |
229 | static notrace int |
230 | trace_seq_putmem(struct trace_seq *s, void *mem, size_t len) | |
231 | { | |
232 | if (len > ((PAGE_SIZE - 1) - s->len)) | |
233 | return 0; | |
234 | ||
235 | memcpy(s->buffer + s->len, mem, len); | |
236 | s->len += len; | |
237 | ||
238 | return len; | |
239 | } | |
240 | ||
214023c3 SR |
241 | static notrace void |
242 | trace_seq_reset(struct trace_seq *s) | |
243 | { | |
244 | s->len = 0; | |
245 | } | |
246 | ||
247 | static notrace void | |
248 | trace_print_seq(struct seq_file *m, struct trace_seq *s) | |
249 | { | |
250 | int len = s->len >= PAGE_SIZE ? PAGE_SIZE - 1 : s->len; | |
251 | ||
252 | s->buffer[len] = 0; | |
253 | seq_puts(m, s->buffer); | |
254 | ||
255 | trace_seq_reset(s); | |
256 | } | |
257 | ||
c7aafc54 IM |
258 | notrace static void |
259 | flip_trace(struct trace_array_cpu *tr1, struct trace_array_cpu *tr2) | |
260 | { | |
261 | struct list_head flip_pages; | |
262 | ||
263 | INIT_LIST_HEAD(&flip_pages); | |
264 | ||
93a588f4 | 265 | memcpy(&tr1->trace_head_idx, &tr2->trace_head_idx, |
c7aafc54 | 266 | sizeof(struct trace_array_cpu) - |
93a588f4 | 267 | offsetof(struct trace_array_cpu, trace_head_idx)); |
c7aafc54 IM |
268 | |
269 | check_pages(tr1); | |
270 | check_pages(tr2); | |
271 | list_splice_init(&tr1->trace_pages, &flip_pages); | |
272 | list_splice_init(&tr2->trace_pages, &tr1->trace_pages); | |
273 | list_splice_init(&flip_pages, &tr2->trace_pages); | |
274 | BUG_ON(!list_empty(&flip_pages)); | |
275 | check_pages(tr1); | |
276 | check_pages(tr2); | |
277 | } | |
278 | ||
bc0c38d1 SR |
279 | notrace void |
280 | update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) | |
281 | { | |
282 | struct trace_array_cpu *data; | |
bc0c38d1 SR |
283 | int i; |
284 | ||
4c11d7ae SR |
285 | WARN_ON_ONCE(!irqs_disabled()); |
286 | spin_lock(&ftrace_max_lock); | |
bc0c38d1 SR |
287 | /* clear out all the previous traces */ |
288 | for_each_possible_cpu(i) { | |
289 | data = tr->data[i]; | |
c7aafc54 | 290 | flip_trace(max_tr.data[i], data); |
89b2f978 | 291 | tracing_reset(data); |
bc0c38d1 SR |
292 | } |
293 | ||
294 | __update_max_tr(tr, tsk, cpu); | |
4c11d7ae | 295 | spin_unlock(&ftrace_max_lock); |
bc0c38d1 SR |
296 | } |
297 | ||
298 | /** | |
299 | * update_max_tr_single - only copy one trace over, and reset the rest | |
300 | * @tr - tracer | |
301 | * @tsk - task with the latency | |
302 | * @cpu - the cpu of the buffer to copy. | |
303 | */ | |
304 | notrace void | |
305 | update_max_tr_single(struct trace_array *tr, struct task_struct *tsk, int cpu) | |
306 | { | |
307 | struct trace_array_cpu *data = tr->data[cpu]; | |
bc0c38d1 SR |
308 | int i; |
309 | ||
4c11d7ae SR |
310 | WARN_ON_ONCE(!irqs_disabled()); |
311 | spin_lock(&ftrace_max_lock); | |
bc0c38d1 SR |
312 | for_each_possible_cpu(i) |
313 | tracing_reset(max_tr.data[i]); | |
314 | ||
c7aafc54 | 315 | flip_trace(max_tr.data[cpu], data); |
89b2f978 | 316 | tracing_reset(data); |
bc0c38d1 SR |
317 | |
318 | __update_max_tr(tr, tsk, cpu); | |
4c11d7ae | 319 | spin_unlock(&ftrace_max_lock); |
bc0c38d1 SR |
320 | } |
321 | ||
322 | int register_tracer(struct tracer *type) | |
323 | { | |
324 | struct tracer *t; | |
325 | int len; | |
326 | int ret = 0; | |
327 | ||
328 | if (!type->name) { | |
329 | pr_info("Tracer must have a name\n"); | |
330 | return -1; | |
331 | } | |
332 | ||
333 | mutex_lock(&trace_types_lock); | |
334 | for (t = trace_types; t; t = t->next) { | |
335 | if (strcmp(type->name, t->name) == 0) { | |
336 | /* already found */ | |
337 | pr_info("Trace %s already registered\n", | |
338 | type->name); | |
339 | ret = -1; | |
340 | goto out; | |
341 | } | |
342 | } | |
343 | ||
60a11774 SR |
344 | #ifdef CONFIG_FTRACE_STARTUP_TEST |
345 | if (type->selftest) { | |
346 | struct tracer *saved_tracer = current_trace; | |
347 | struct trace_array_cpu *data; | |
348 | struct trace_array *tr = &global_trace; | |
349 | int saved_ctrl = tr->ctrl; | |
350 | int i; | |
351 | /* | |
352 | * Run a selftest on this tracer. | |
353 | * Here we reset the trace buffer, and set the current | |
354 | * tracer to be this tracer. The tracer can then run some | |
355 | * internal tracing to verify that everything is in order. | |
356 | * If we fail, we do not register this tracer. | |
357 | */ | |
358 | for_each_possible_cpu(i) { | |
60a11774 | 359 | data = tr->data[i]; |
c7aafc54 IM |
360 | if (!head_page(data)) |
361 | continue; | |
60a11774 SR |
362 | tracing_reset(data); |
363 | } | |
364 | current_trace = type; | |
365 | tr->ctrl = 0; | |
366 | /* the test is responsible for initializing and enabling */ | |
367 | pr_info("Testing tracer %s: ", type->name); | |
368 | ret = type->selftest(type, tr); | |
369 | /* the test is responsible for resetting too */ | |
370 | current_trace = saved_tracer; | |
371 | tr->ctrl = saved_ctrl; | |
372 | if (ret) { | |
373 | printk(KERN_CONT "FAILED!\n"); | |
374 | goto out; | |
375 | } | |
1d4db00a SR |
376 | /* Only reset on passing, to avoid touching corrupted buffers */ |
377 | for_each_possible_cpu(i) { | |
378 | data = tr->data[i]; | |
379 | if (!head_page(data)) | |
380 | continue; | |
381 | tracing_reset(data); | |
382 | } | |
60a11774 SR |
383 | printk(KERN_CONT "PASSED\n"); |
384 | } | |
385 | #endif | |
386 | ||
bc0c38d1 SR |
387 | type->next = trace_types; |
388 | trace_types = type; | |
389 | len = strlen(type->name); | |
390 | if (len > max_tracer_type_len) | |
391 | max_tracer_type_len = len; | |
60a11774 | 392 | |
bc0c38d1 SR |
393 | out: |
394 | mutex_unlock(&trace_types_lock); | |
395 | ||
396 | return ret; | |
397 | } | |
398 | ||
399 | void unregister_tracer(struct tracer *type) | |
400 | { | |
401 | struct tracer **t; | |
402 | int len; | |
403 | ||
404 | mutex_lock(&trace_types_lock); | |
405 | for (t = &trace_types; *t; t = &(*t)->next) { | |
406 | if (*t == type) | |
407 | goto found; | |
408 | } | |
409 | pr_info("Trace %s not registered\n", type->name); | |
410 | goto out; | |
411 | ||
412 | found: | |
413 | *t = (*t)->next; | |
414 | if (strlen(type->name) != max_tracer_type_len) | |
415 | goto out; | |
416 | ||
417 | max_tracer_type_len = 0; | |
418 | for (t = &trace_types; *t; t = &(*t)->next) { | |
419 | len = strlen((*t)->name); | |
420 | if (len > max_tracer_type_len) | |
421 | max_tracer_type_len = len; | |
422 | } | |
423 | out: | |
424 | mutex_unlock(&trace_types_lock); | |
425 | } | |
426 | ||
4e3c3333 | 427 | notrace void tracing_reset(struct trace_array_cpu *data) |
bc0c38d1 SR |
428 | { |
429 | data->trace_idx = 0; | |
93a588f4 SR |
430 | data->trace_head = data->trace_tail = head_page(data); |
431 | data->trace_head_idx = 0; | |
432 | data->trace_tail_idx = 0; | |
bc0c38d1 SR |
433 | } |
434 | ||
435 | #ifdef CONFIG_FTRACE | |
4e3c3333 | 436 | static notrace void |
bc0c38d1 SR |
437 | function_trace_call(unsigned long ip, unsigned long parent_ip) |
438 | { | |
439 | struct trace_array *tr = &global_trace; | |
440 | struct trace_array_cpu *data; | |
441 | unsigned long flags; | |
442 | long disabled; | |
443 | int cpu; | |
444 | ||
445 | if (unlikely(!tracer_enabled)) | |
446 | return; | |
447 | ||
18cef379 | 448 | local_irq_save(flags); |
bc0c38d1 SR |
449 | cpu = raw_smp_processor_id(); |
450 | data = tr->data[cpu]; | |
451 | disabled = atomic_inc_return(&data->disabled); | |
452 | ||
453 | if (likely(disabled == 1)) | |
454 | ftrace(tr, data, ip, parent_ip, flags); | |
455 | ||
456 | atomic_dec(&data->disabled); | |
18cef379 | 457 | local_irq_restore(flags); |
bc0c38d1 SR |
458 | } |
459 | ||
460 | static struct ftrace_ops trace_ops __read_mostly = | |
461 | { | |
462 | .func = function_trace_call, | |
463 | }; | |
464 | #endif | |
465 | ||
466 | notrace void tracing_start_function_trace(void) | |
467 | { | |
468 | register_ftrace_function(&trace_ops); | |
469 | } | |
470 | ||
471 | notrace void tracing_stop_function_trace(void) | |
472 | { | |
473 | unregister_ftrace_function(&trace_ops); | |
474 | } | |
475 | ||
476 | #define SAVED_CMDLINES 128 | |
477 | static unsigned map_pid_to_cmdline[PID_MAX_DEFAULT+1]; | |
478 | static unsigned map_cmdline_to_pid[SAVED_CMDLINES]; | |
479 | static char saved_cmdlines[SAVED_CMDLINES][TASK_COMM_LEN]; | |
480 | static int cmdline_idx; | |
481 | static DEFINE_SPINLOCK(trace_cmdline_lock); | |
482 | atomic_t trace_record_cmdline_disabled; | |
483 | ||
484 | static void trace_init_cmdlines(void) | |
485 | { | |
486 | memset(&map_pid_to_cmdline, -1, sizeof(map_pid_to_cmdline)); | |
487 | memset(&map_cmdline_to_pid, -1, sizeof(map_cmdline_to_pid)); | |
488 | cmdline_idx = 0; | |
489 | } | |
490 | ||
491 | notrace void trace_stop_cmdline_recording(void); | |
492 | ||
4e3c3333 | 493 | static notrace void trace_save_cmdline(struct task_struct *tsk) |
bc0c38d1 SR |
494 | { |
495 | unsigned map; | |
496 | unsigned idx; | |
497 | ||
498 | if (!tsk->pid || unlikely(tsk->pid > PID_MAX_DEFAULT)) | |
499 | return; | |
500 | ||
501 | /* | |
502 | * It's not the end of the world if we don't get | |
503 | * the lock, but we also don't want to spin | |
504 | * nor do we want to disable interrupts, | |
505 | * so if we miss here, then better luck next time. | |
506 | */ | |
507 | if (!spin_trylock(&trace_cmdline_lock)) | |
508 | return; | |
509 | ||
510 | idx = map_pid_to_cmdline[tsk->pid]; | |
511 | if (idx >= SAVED_CMDLINES) { | |
512 | idx = (cmdline_idx + 1) % SAVED_CMDLINES; | |
513 | ||
514 | map = map_cmdline_to_pid[idx]; | |
515 | if (map <= PID_MAX_DEFAULT) | |
516 | map_pid_to_cmdline[map] = (unsigned)-1; | |
517 | ||
518 | map_pid_to_cmdline[tsk->pid] = idx; | |
519 | ||
520 | cmdline_idx = idx; | |
521 | } | |
522 | ||
523 | memcpy(&saved_cmdlines[idx], tsk->comm, TASK_COMM_LEN); | |
524 | ||
525 | spin_unlock(&trace_cmdline_lock); | |
526 | } | |
527 | ||
528 | static notrace char *trace_find_cmdline(int pid) | |
529 | { | |
530 | char *cmdline = "<...>"; | |
531 | unsigned map; | |
532 | ||
533 | if (!pid) | |
534 | return "<idle>"; | |
535 | ||
536 | if (pid > PID_MAX_DEFAULT) | |
537 | goto out; | |
538 | ||
539 | map = map_pid_to_cmdline[pid]; | |
540 | if (map >= SAVED_CMDLINES) | |
541 | goto out; | |
542 | ||
543 | cmdline = saved_cmdlines[map]; | |
544 | ||
545 | out: | |
546 | return cmdline; | |
547 | } | |
548 | ||
549 | notrace void tracing_record_cmdline(struct task_struct *tsk) | |
550 | { | |
551 | if (atomic_read(&trace_record_cmdline_disabled)) | |
552 | return; | |
553 | ||
554 | trace_save_cmdline(tsk); | |
555 | } | |
556 | ||
93a588f4 SR |
557 | static inline notrace struct list_head * |
558 | trace_next_list(struct trace_array_cpu *data, struct list_head *next) | |
559 | { | |
560 | /* | |
561 | * Roundrobin - but skip the head (which is not a real page): | |
562 | */ | |
563 | next = next->next; | |
564 | if (unlikely(next == &data->trace_pages)) | |
565 | next = next->next; | |
566 | BUG_ON(next == &data->trace_pages); | |
567 | ||
568 | return next; | |
569 | } | |
570 | ||
571 | static inline notrace void * | |
572 | trace_next_page(struct trace_array_cpu *data, void *addr) | |
573 | { | |
574 | struct list_head *next; | |
575 | struct page *page; | |
576 | ||
577 | page = virt_to_page(addr); | |
578 | ||
579 | next = trace_next_list(data, &page->lru); | |
580 | page = list_entry(next, struct page, lru); | |
581 | ||
582 | return page_address(page); | |
583 | } | |
584 | ||
bc0c38d1 | 585 | static inline notrace struct trace_entry * |
c7aafc54 | 586 | tracing_get_trace_entry(struct trace_array *tr, struct trace_array_cpu *data) |
bc0c38d1 SR |
587 | { |
588 | unsigned long idx, idx_next; | |
589 | struct trace_entry *entry; | |
590 | ||
4c11d7ae | 591 | data->trace_idx++; |
93a588f4 | 592 | idx = data->trace_head_idx; |
bc0c38d1 SR |
593 | idx_next = idx + 1; |
594 | ||
c7aafc54 IM |
595 | BUG_ON(idx * TRACE_ENTRY_SIZE >= PAGE_SIZE); |
596 | ||
93a588f4 | 597 | entry = data->trace_head + idx * TRACE_ENTRY_SIZE; |
4c11d7ae SR |
598 | |
599 | if (unlikely(idx_next >= ENTRIES_PER_PAGE)) { | |
93a588f4 | 600 | data->trace_head = trace_next_page(data, data->trace_head); |
bc0c38d1 SR |
601 | idx_next = 0; |
602 | } | |
603 | ||
93a588f4 SR |
604 | if (data->trace_head == data->trace_tail && |
605 | idx_next == data->trace_tail_idx) { | |
606 | /* overrun */ | |
607 | data->trace_tail_idx++; | |
608 | if (data->trace_tail_idx >= ENTRIES_PER_PAGE) { | |
609 | data->trace_tail = | |
610 | trace_next_page(data, data->trace_tail); | |
611 | data->trace_tail_idx = 0; | |
612 | } | |
613 | } | |
614 | ||
615 | data->trace_head_idx = idx_next; | |
bc0c38d1 SR |
616 | |
617 | return entry; | |
618 | } | |
619 | ||
620 | static inline notrace void | |
c7aafc54 | 621 | tracing_generic_entry_update(struct trace_entry *entry, unsigned long flags) |
bc0c38d1 SR |
622 | { |
623 | struct task_struct *tsk = current; | |
624 | unsigned long pc; | |
625 | ||
626 | pc = preempt_count(); | |
627 | ||
c7aafc54 IM |
628 | entry->preempt_count = pc & 0xff; |
629 | entry->pid = tsk->pid; | |
750ed1a4 | 630 | entry->t = ftrace_now(raw_smp_processor_id()); |
bc0c38d1 SR |
631 | entry->flags = (irqs_disabled_flags(flags) ? TRACE_FLAG_IRQS_OFF : 0) | |
632 | ((pc & HARDIRQ_MASK) ? TRACE_FLAG_HARDIRQ : 0) | | |
633 | ((pc & SOFTIRQ_MASK) ? TRACE_FLAG_SOFTIRQ : 0) | | |
634 | (need_resched() ? TRACE_FLAG_NEED_RESCHED : 0); | |
635 | } | |
636 | ||
637 | notrace void | |
638 | ftrace(struct trace_array *tr, struct trace_array_cpu *data, | |
c7aafc54 | 639 | unsigned long ip, unsigned long parent_ip, unsigned long flags) |
bc0c38d1 SR |
640 | { |
641 | struct trace_entry *entry; | |
dcb6308f | 642 | unsigned long irq_flags; |
bc0c38d1 | 643 | |
dcb6308f | 644 | spin_lock_irqsave(&data->lock, irq_flags); |
c7aafc54 | 645 | entry = tracing_get_trace_entry(tr, data); |
bc0c38d1 | 646 | tracing_generic_entry_update(entry, flags); |
c7aafc54 IM |
647 | entry->type = TRACE_FN; |
648 | entry->fn.ip = ip; | |
649 | entry->fn.parent_ip = parent_ip; | |
dcb6308f | 650 | spin_unlock_irqrestore(&data->lock, irq_flags); |
bc0c38d1 SR |
651 | } |
652 | ||
f0a920d5 IM |
653 | notrace void |
654 | trace_special(struct trace_array *tr, struct trace_array_cpu *data, | |
655 | unsigned long arg1, unsigned long arg2, unsigned long arg3) | |
656 | { | |
657 | struct trace_entry *entry; | |
dcb6308f | 658 | unsigned long irq_flags; |
f0a920d5 | 659 | |
dcb6308f | 660 | spin_lock_irqsave(&data->lock, irq_flags); |
f0a920d5 IM |
661 | entry = tracing_get_trace_entry(tr, data); |
662 | tracing_generic_entry_update(entry, 0); | |
663 | entry->type = TRACE_SPECIAL; | |
664 | entry->special.arg1 = arg1; | |
665 | entry->special.arg2 = arg2; | |
666 | entry->special.arg3 = arg3; | |
dcb6308f | 667 | spin_unlock_irqrestore(&data->lock, irq_flags); |
f0a920d5 IM |
668 | } |
669 | ||
bc0c38d1 SR |
670 | notrace void |
671 | tracing_sched_switch_trace(struct trace_array *tr, | |
672 | struct trace_array_cpu *data, | |
673 | struct task_struct *prev, struct task_struct *next, | |
674 | unsigned long flags) | |
675 | { | |
676 | struct trace_entry *entry; | |
dcb6308f | 677 | unsigned long irq_flags; |
bc0c38d1 | 678 | |
dcb6308f | 679 | spin_lock_irqsave(&data->lock, irq_flags); |
c7aafc54 | 680 | entry = tracing_get_trace_entry(tr, data); |
bc0c38d1 SR |
681 | tracing_generic_entry_update(entry, flags); |
682 | entry->type = TRACE_CTX; | |
683 | entry->ctx.prev_pid = prev->pid; | |
684 | entry->ctx.prev_prio = prev->prio; | |
685 | entry->ctx.prev_state = prev->state; | |
686 | entry->ctx.next_pid = next->pid; | |
687 | entry->ctx.next_prio = next->prio; | |
dcb6308f | 688 | spin_unlock_irqrestore(&data->lock, irq_flags); |
bc0c38d1 SR |
689 | } |
690 | ||
691 | enum trace_file_type { | |
692 | TRACE_FILE_LAT_FMT = 1, | |
693 | }; | |
694 | ||
695 | static struct trace_entry * | |
4c11d7ae SR |
696 | trace_entry_idx(struct trace_array *tr, struct trace_array_cpu *data, |
697 | struct trace_iterator *iter, int cpu) | |
bc0c38d1 | 698 | { |
4c11d7ae SR |
699 | struct page *page; |
700 | struct trace_entry *array; | |
bc0c38d1 | 701 | |
4c11d7ae | 702 | if (iter->next_idx[cpu] >= tr->entries || |
b3806b43 SR |
703 | iter->next_idx[cpu] >= data->trace_idx || |
704 | (data->trace_head == data->trace_tail && | |
705 | data->trace_head_idx == data->trace_tail_idx)) | |
bc0c38d1 SR |
706 | return NULL; |
707 | ||
4c11d7ae | 708 | if (!iter->next_page[cpu]) { |
93a588f4 SR |
709 | /* Initialize the iterator for this cpu trace buffer */ |
710 | WARN_ON(!data->trace_tail); | |
711 | page = virt_to_page(data->trace_tail); | |
712 | iter->next_page[cpu] = &page->lru; | |
713 | iter->next_page_idx[cpu] = data->trace_tail_idx; | |
4c11d7ae | 714 | } |
bc0c38d1 | 715 | |
4c11d7ae | 716 | page = list_entry(iter->next_page[cpu], struct page, lru); |
c7aafc54 IM |
717 | BUG_ON(&data->trace_pages == &page->lru); |
718 | ||
4c11d7ae SR |
719 | array = page_address(page); |
720 | ||
93a588f4 | 721 | WARN_ON(iter->next_page_idx[cpu] >= ENTRIES_PER_PAGE); |
4c11d7ae | 722 | return &array[iter->next_page_idx[cpu]]; |
bc0c38d1 SR |
723 | } |
724 | ||
725 | static struct notrace trace_entry * | |
726 | find_next_entry(struct trace_iterator *iter, int *ent_cpu) | |
727 | { | |
728 | struct trace_array *tr = iter->tr; | |
729 | struct trace_entry *ent, *next = NULL; | |
730 | int next_cpu = -1; | |
731 | int cpu; | |
732 | ||
733 | for_each_possible_cpu(cpu) { | |
c7aafc54 | 734 | if (!head_page(tr->data[cpu])) |
bc0c38d1 | 735 | continue; |
4c11d7ae | 736 | ent = trace_entry_idx(tr, tr->data[cpu], iter, cpu); |
cdd31cd2 IM |
737 | /* |
738 | * Pick the entry with the smallest timestamp: | |
739 | */ | |
740 | if (ent && (!next || ent->t < next->t)) { | |
bc0c38d1 SR |
741 | next = ent; |
742 | next_cpu = cpu; | |
743 | } | |
744 | } | |
745 | ||
746 | if (ent_cpu) | |
747 | *ent_cpu = next_cpu; | |
748 | ||
749 | return next; | |
750 | } | |
751 | ||
8c523a9d | 752 | static notrace void trace_iterator_increment(struct trace_iterator *iter) |
bc0c38d1 | 753 | { |
b3806b43 SR |
754 | iter->idx++; |
755 | iter->next_idx[iter->cpu]++; | |
756 | iter->next_page_idx[iter->cpu]++; | |
8c523a9d | 757 | |
b3806b43 SR |
758 | if (iter->next_page_idx[iter->cpu] >= ENTRIES_PER_PAGE) { |
759 | struct trace_array_cpu *data = iter->tr->data[iter->cpu]; | |
bc0c38d1 | 760 | |
b3806b43 SR |
761 | iter->next_page_idx[iter->cpu] = 0; |
762 | iter->next_page[iter->cpu] = | |
763 | trace_next_list(data, iter->next_page[iter->cpu]); | |
764 | } | |
765 | } | |
bc0c38d1 | 766 | |
8c523a9d | 767 | static notrace void trace_consume(struct trace_iterator *iter) |
b3806b43 SR |
768 | { |
769 | struct trace_array_cpu *data = iter->tr->data[iter->cpu]; | |
770 | ||
771 | data->trace_tail_idx++; | |
772 | if (data->trace_tail_idx >= ENTRIES_PER_PAGE) { | |
773 | data->trace_tail = trace_next_page(data, data->trace_tail); | |
774 | data->trace_tail_idx = 0; | |
775 | } | |
4e3c3333 | 776 | |
b3806b43 SR |
777 | /* Check if we empty it, then reset the index */ |
778 | if (data->trace_head == data->trace_tail && | |
779 | data->trace_head_idx == data->trace_tail_idx) | |
780 | data->trace_idx = 0; | |
b3806b43 SR |
781 | } |
782 | ||
8c523a9d | 783 | static notrace void *find_next_entry_inc(struct trace_iterator *iter) |
b3806b43 SR |
784 | { |
785 | struct trace_entry *next; | |
786 | int next_cpu = -1; | |
787 | ||
788 | next = find_next_entry(iter, &next_cpu); | |
93a588f4 | 789 | |
4e3c3333 IM |
790 | iter->prev_ent = iter->ent; |
791 | iter->prev_cpu = iter->cpu; | |
792 | ||
bc0c38d1 SR |
793 | iter->ent = next; |
794 | iter->cpu = next_cpu; | |
795 | ||
b3806b43 SR |
796 | if (next) |
797 | trace_iterator_increment(iter); | |
798 | ||
bc0c38d1 SR |
799 | return next ? iter : NULL; |
800 | } | |
801 | ||
4e3c3333 | 802 | static notrace void *s_next(struct seq_file *m, void *v, loff_t *pos) |
bc0c38d1 SR |
803 | { |
804 | struct trace_iterator *iter = m->private; | |
bc0c38d1 SR |
805 | void *last_ent = iter->ent; |
806 | int i = (int)*pos; | |
4e3c3333 | 807 | void *ent; |
bc0c38d1 SR |
808 | |
809 | (*pos)++; | |
810 | ||
811 | /* can't go backwards */ | |
812 | if (iter->idx > i) | |
813 | return NULL; | |
814 | ||
815 | if (iter->idx < 0) | |
816 | ent = find_next_entry_inc(iter); | |
817 | else | |
818 | ent = iter; | |
819 | ||
820 | while (ent && iter->idx < i) | |
821 | ent = find_next_entry_inc(iter); | |
822 | ||
823 | iter->pos = *pos; | |
824 | ||
825 | if (last_ent && !ent) | |
826 | seq_puts(m, "\n\nvim:ft=help\n"); | |
827 | ||
828 | return ent; | |
829 | } | |
830 | ||
831 | static void *s_start(struct seq_file *m, loff_t *pos) | |
832 | { | |
833 | struct trace_iterator *iter = m->private; | |
834 | void *p = NULL; | |
835 | loff_t l = 0; | |
836 | int i; | |
837 | ||
838 | mutex_lock(&trace_types_lock); | |
839 | ||
840 | if (!current_trace || current_trace != iter->trace) | |
841 | return NULL; | |
842 | ||
843 | atomic_inc(&trace_record_cmdline_disabled); | |
844 | ||
845 | /* let the tracer grab locks here if needed */ | |
846 | if (current_trace->start) | |
847 | current_trace->start(iter); | |
848 | ||
849 | if (*pos != iter->pos) { | |
850 | iter->ent = NULL; | |
851 | iter->cpu = 0; | |
852 | iter->idx = -1; | |
4e3c3333 IM |
853 | iter->prev_ent = NULL; |
854 | iter->prev_cpu = -1; | |
bc0c38d1 | 855 | |
4c11d7ae | 856 | for_each_possible_cpu(i) { |
bc0c38d1 | 857 | iter->next_idx[i] = 0; |
4c11d7ae SR |
858 | iter->next_page[i] = NULL; |
859 | } | |
bc0c38d1 SR |
860 | |
861 | for (p = iter; p && l < *pos; p = s_next(m, p, &l)) | |
862 | ; | |
863 | ||
864 | } else { | |
4c11d7ae | 865 | l = *pos - 1; |
bc0c38d1 SR |
866 | p = s_next(m, p, &l); |
867 | } | |
868 | ||
869 | return p; | |
870 | } | |
871 | ||
872 | static void s_stop(struct seq_file *m, void *p) | |
873 | { | |
874 | struct trace_iterator *iter = m->private; | |
875 | ||
876 | atomic_dec(&trace_record_cmdline_disabled); | |
877 | ||
878 | /* let the tracer release locks here if needed */ | |
879 | if (current_trace && current_trace == iter->trace && iter->trace->stop) | |
880 | iter->trace->stop(iter); | |
881 | ||
882 | mutex_unlock(&trace_types_lock); | |
883 | } | |
884 | ||
b3806b43 | 885 | static int |
214023c3 | 886 | seq_print_sym_short(struct trace_seq *s, const char *fmt, unsigned long address) |
bc0c38d1 SR |
887 | { |
888 | #ifdef CONFIG_KALLSYMS | |
889 | char str[KSYM_SYMBOL_LEN]; | |
890 | ||
891 | kallsyms_lookup(address, NULL, NULL, NULL, str); | |
892 | ||
b3806b43 | 893 | return trace_seq_printf(s, fmt, str); |
bc0c38d1 | 894 | #endif |
b3806b43 | 895 | return 1; |
bc0c38d1 SR |
896 | } |
897 | ||
b3806b43 | 898 | static int |
214023c3 SR |
899 | seq_print_sym_offset(struct trace_seq *s, const char *fmt, |
900 | unsigned long address) | |
bc0c38d1 SR |
901 | { |
902 | #ifdef CONFIG_KALLSYMS | |
903 | char str[KSYM_SYMBOL_LEN]; | |
904 | ||
905 | sprint_symbol(str, address); | |
b3806b43 | 906 | return trace_seq_printf(s, fmt, str); |
bc0c38d1 | 907 | #endif |
b3806b43 | 908 | return 1; |
bc0c38d1 SR |
909 | } |
910 | ||
911 | #ifndef CONFIG_64BIT | |
912 | # define IP_FMT "%08lx" | |
913 | #else | |
914 | # define IP_FMT "%016lx" | |
915 | #endif | |
916 | ||
b3806b43 | 917 | static notrace int |
214023c3 | 918 | seq_print_ip_sym(struct trace_seq *s, unsigned long ip, unsigned long sym_flags) |
bc0c38d1 | 919 | { |
b3806b43 SR |
920 | int ret; |
921 | ||
922 | if (!ip) | |
923 | return trace_seq_printf(s, "0"); | |
bc0c38d1 SR |
924 | |
925 | if (sym_flags & TRACE_ITER_SYM_OFFSET) | |
b3806b43 | 926 | ret = seq_print_sym_offset(s, "%s", ip); |
bc0c38d1 | 927 | else |
b3806b43 SR |
928 | ret = seq_print_sym_short(s, "%s", ip); |
929 | ||
930 | if (!ret) | |
931 | return 0; | |
bc0c38d1 SR |
932 | |
933 | if (sym_flags & TRACE_ITER_SYM_ADDR) | |
b3806b43 SR |
934 | ret = trace_seq_printf(s, " <" IP_FMT ">", ip); |
935 | return ret; | |
bc0c38d1 SR |
936 | } |
937 | ||
4e3c3333 | 938 | static notrace void print_lat_help_header(struct seq_file *m) |
bc0c38d1 SR |
939 | { |
940 | seq_puts(m, "# _------=> CPU# \n"); | |
941 | seq_puts(m, "# / _-----=> irqs-off \n"); | |
942 | seq_puts(m, "# | / _----=> need-resched \n"); | |
943 | seq_puts(m, "# || / _---=> hardirq/softirq \n"); | |
944 | seq_puts(m, "# ||| / _--=> preempt-depth \n"); | |
945 | seq_puts(m, "# |||| / \n"); | |
946 | seq_puts(m, "# ||||| delay \n"); | |
947 | seq_puts(m, "# cmd pid ||||| time | caller \n"); | |
948 | seq_puts(m, "# \\ / ||||| \\ | / \n"); | |
949 | } | |
950 | ||
4e3c3333 | 951 | static notrace void print_func_help_header(struct seq_file *m) |
bc0c38d1 SR |
952 | { |
953 | seq_puts(m, "# TASK-PID CPU# TIMESTAMP FUNCTION\n"); | |
954 | seq_puts(m, "# | | | | |\n"); | |
955 | } | |
956 | ||
957 | ||
4e3c3333 | 958 | static notrace void |
bc0c38d1 SR |
959 | print_trace_header(struct seq_file *m, struct trace_iterator *iter) |
960 | { | |
961 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); | |
962 | struct trace_array *tr = iter->tr; | |
963 | struct trace_array_cpu *data = tr->data[tr->cpu]; | |
964 | struct tracer *type = current_trace; | |
4c11d7ae SR |
965 | unsigned long total = 0; |
966 | unsigned long entries = 0; | |
bc0c38d1 SR |
967 | int cpu; |
968 | const char *name = "preemption"; | |
969 | ||
970 | if (type) | |
971 | name = type->name; | |
972 | ||
973 | for_each_possible_cpu(cpu) { | |
c7aafc54 | 974 | if (head_page(tr->data[cpu])) { |
4c11d7ae SR |
975 | total += tr->data[cpu]->trace_idx; |
976 | if (tr->data[cpu]->trace_idx > tr->entries) | |
bc0c38d1 | 977 | entries += tr->entries; |
4c11d7ae | 978 | else |
bc0c38d1 SR |
979 | entries += tr->data[cpu]->trace_idx; |
980 | } | |
981 | } | |
982 | ||
983 | seq_printf(m, "%s latency trace v1.1.5 on %s\n", | |
984 | name, UTS_RELEASE); | |
985 | seq_puts(m, "-----------------------------------" | |
986 | "---------------------------------\n"); | |
987 | seq_printf(m, " latency: %lu us, #%lu/%lu, CPU#%d |" | |
988 | " (M:%s VP:%d, KP:%d, SP:%d HP:%d", | |
57f50be1 | 989 | nsecs_to_usecs(data->saved_latency), |
bc0c38d1 | 990 | entries, |
4c11d7ae | 991 | total, |
bc0c38d1 SR |
992 | tr->cpu, |
993 | #if defined(CONFIG_PREEMPT_NONE) | |
994 | "server", | |
995 | #elif defined(CONFIG_PREEMPT_VOLUNTARY) | |
996 | "desktop", | |
997 | #elif defined(CONFIG_PREEMPT_DESKTOP) | |
998 | "preempt", | |
999 | #else | |
1000 | "unknown", | |
1001 | #endif | |
1002 | /* These are reserved for later use */ | |
1003 | 0, 0, 0, 0); | |
1004 | #ifdef CONFIG_SMP | |
1005 | seq_printf(m, " #P:%d)\n", num_online_cpus()); | |
1006 | #else | |
1007 | seq_puts(m, ")\n"); | |
1008 | #endif | |
1009 | seq_puts(m, " -----------------\n"); | |
1010 | seq_printf(m, " | task: %.16s-%d " | |
1011 | "(uid:%d nice:%ld policy:%ld rt_prio:%ld)\n", | |
1012 | data->comm, data->pid, data->uid, data->nice, | |
1013 | data->policy, data->rt_priority); | |
1014 | seq_puts(m, " -----------------\n"); | |
1015 | ||
1016 | if (data->critical_start) { | |
1017 | seq_puts(m, " => started at: "); | |
214023c3 SR |
1018 | seq_print_ip_sym(&iter->seq, data->critical_start, sym_flags); |
1019 | trace_print_seq(m, &iter->seq); | |
bc0c38d1 | 1020 | seq_puts(m, "\n => ended at: "); |
214023c3 SR |
1021 | seq_print_ip_sym(&iter->seq, data->critical_end, sym_flags); |
1022 | trace_print_seq(m, &iter->seq); | |
bc0c38d1 SR |
1023 | seq_puts(m, "\n"); |
1024 | } | |
1025 | ||
1026 | seq_puts(m, "\n"); | |
1027 | } | |
1028 | ||
4e3c3333 | 1029 | static notrace void |
214023c3 | 1030 | lat_print_generic(struct trace_seq *s, struct trace_entry *entry, int cpu) |
bc0c38d1 SR |
1031 | { |
1032 | int hardirq, softirq; | |
1033 | char *comm; | |
1034 | ||
1035 | comm = trace_find_cmdline(entry->pid); | |
1036 | ||
214023c3 SR |
1037 | trace_seq_printf(s, "%8.8s-%-5d ", comm, entry->pid); |
1038 | trace_seq_printf(s, "%d", cpu); | |
1039 | trace_seq_printf(s, "%c%c", | |
1040 | (entry->flags & TRACE_FLAG_IRQS_OFF) ? 'd' : '.', | |
1041 | ((entry->flags & TRACE_FLAG_NEED_RESCHED) ? 'N' : '.')); | |
bc0c38d1 SR |
1042 | |
1043 | hardirq = entry->flags & TRACE_FLAG_HARDIRQ; | |
1044 | softirq = entry->flags & TRACE_FLAG_SOFTIRQ; | |
1045 | if (hardirq && softirq) | |
214023c3 | 1046 | trace_seq_putc(s, 'H'); |
bc0c38d1 SR |
1047 | else { |
1048 | if (hardirq) | |
214023c3 | 1049 | trace_seq_putc(s, 'h'); |
bc0c38d1 SR |
1050 | else { |
1051 | if (softirq) | |
214023c3 | 1052 | trace_seq_putc(s, 's'); |
bc0c38d1 | 1053 | else |
214023c3 | 1054 | trace_seq_putc(s, '.'); |
bc0c38d1 SR |
1055 | } |
1056 | } | |
1057 | ||
1058 | if (entry->preempt_count) | |
214023c3 | 1059 | trace_seq_printf(s, "%x", entry->preempt_count); |
bc0c38d1 | 1060 | else |
214023c3 | 1061 | trace_seq_puts(s, "."); |
bc0c38d1 SR |
1062 | } |
1063 | ||
1064 | unsigned long preempt_mark_thresh = 100; | |
1065 | ||
4e3c3333 | 1066 | static notrace void |
214023c3 | 1067 | lat_print_timestamp(struct trace_seq *s, unsigned long long abs_usecs, |
bc0c38d1 SR |
1068 | unsigned long rel_usecs) |
1069 | { | |
214023c3 | 1070 | trace_seq_printf(s, " %4lldus", abs_usecs); |
bc0c38d1 | 1071 | if (rel_usecs > preempt_mark_thresh) |
214023c3 | 1072 | trace_seq_puts(s, "!: "); |
bc0c38d1 | 1073 | else if (rel_usecs > 1) |
214023c3 | 1074 | trace_seq_puts(s, "+: "); |
bc0c38d1 | 1075 | else |
214023c3 | 1076 | trace_seq_puts(s, " : "); |
bc0c38d1 SR |
1077 | } |
1078 | ||
1079 | static const char state_to_char[] = TASK_STATE_TO_CHAR_STR; | |
1080 | ||
f9896bf3 | 1081 | static notrace int |
214023c3 | 1082 | print_lat_fmt(struct trace_iterator *iter, unsigned int trace_idx, int cpu) |
bc0c38d1 | 1083 | { |
214023c3 | 1084 | struct trace_seq *s = &iter->seq; |
bc0c38d1 SR |
1085 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); |
1086 | struct trace_entry *next_entry = find_next_entry(iter, NULL); | |
1087 | unsigned long verbose = (trace_flags & TRACE_ITER_VERBOSE); | |
1088 | struct trace_entry *entry = iter->ent; | |
1089 | unsigned long abs_usecs; | |
1090 | unsigned long rel_usecs; | |
1091 | char *comm; | |
1092 | int S; | |
1093 | ||
1094 | if (!next_entry) | |
1095 | next_entry = entry; | |
1096 | rel_usecs = ns2usecs(next_entry->t - entry->t); | |
1097 | abs_usecs = ns2usecs(entry->t - iter->tr->time_start); | |
1098 | ||
1099 | if (verbose) { | |
1100 | comm = trace_find_cmdline(entry->pid); | |
214023c3 SR |
1101 | trace_seq_printf(s, "%16s %5d %d %d %08x %08x [%08lx]" |
1102 | " %ld.%03ldms (+%ld.%03ldms): ", | |
1103 | comm, | |
1104 | entry->pid, cpu, entry->flags, | |
1105 | entry->preempt_count, trace_idx, | |
1106 | ns2usecs(entry->t), | |
1107 | abs_usecs/1000, | |
1108 | abs_usecs % 1000, rel_usecs/1000, | |
1109 | rel_usecs % 1000); | |
bc0c38d1 | 1110 | } else { |
214023c3 SR |
1111 | lat_print_generic(s, entry, cpu); |
1112 | lat_print_timestamp(s, abs_usecs, rel_usecs); | |
bc0c38d1 SR |
1113 | } |
1114 | switch (entry->type) { | |
1115 | case TRACE_FN: | |
214023c3 SR |
1116 | seq_print_ip_sym(s, entry->fn.ip, sym_flags); |
1117 | trace_seq_puts(s, " ("); | |
1118 | seq_print_ip_sym(s, entry->fn.parent_ip, sym_flags); | |
1119 | trace_seq_puts(s, ")\n"); | |
bc0c38d1 SR |
1120 | break; |
1121 | case TRACE_CTX: | |
1122 | S = entry->ctx.prev_state < sizeof(state_to_char) ? | |
1123 | state_to_char[entry->ctx.prev_state] : 'X'; | |
1124 | comm = trace_find_cmdline(entry->ctx.next_pid); | |
214023c3 SR |
1125 | trace_seq_printf(s, " %d:%d:%c --> %d:%d %s\n", |
1126 | entry->ctx.prev_pid, | |
1127 | entry->ctx.prev_prio, | |
1128 | S, | |
1129 | entry->ctx.next_pid, | |
1130 | entry->ctx.next_prio, | |
1131 | comm); | |
bc0c38d1 | 1132 | break; |
f0a920d5 IM |
1133 | case TRACE_SPECIAL: |
1134 | trace_seq_printf(s, " %lx %lx %lx\n", | |
1135 | entry->special.arg1, | |
1136 | entry->special.arg2, | |
1137 | entry->special.arg3); | |
1138 | break; | |
89b2f978 | 1139 | default: |
214023c3 | 1140 | trace_seq_printf(s, "Unknown type %d\n", entry->type); |
bc0c38d1 | 1141 | } |
f9896bf3 | 1142 | return 1; |
bc0c38d1 SR |
1143 | } |
1144 | ||
f9896bf3 | 1145 | static notrace int print_trace_fmt(struct trace_iterator *iter) |
bc0c38d1 | 1146 | { |
214023c3 | 1147 | struct trace_seq *s = &iter->seq; |
bc0c38d1 | 1148 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); |
4e3c3333 | 1149 | struct trace_entry *entry; |
bc0c38d1 SR |
1150 | unsigned long usec_rem; |
1151 | unsigned long long t; | |
1152 | unsigned long secs; | |
1153 | char *comm; | |
1154 | int S; | |
b3806b43 | 1155 | int ret; |
bc0c38d1 | 1156 | |
4e3c3333 IM |
1157 | entry = iter->ent; |
1158 | ||
bc0c38d1 SR |
1159 | comm = trace_find_cmdline(iter->ent->pid); |
1160 | ||
cdd31cd2 | 1161 | t = ns2usecs(entry->t); |
bc0c38d1 SR |
1162 | usec_rem = do_div(t, 1000000ULL); |
1163 | secs = (unsigned long)t; | |
1164 | ||
b3806b43 SR |
1165 | ret = trace_seq_printf(s, "%16s-%-5d ", comm, entry->pid); |
1166 | if (!ret) | |
1167 | return 0; | |
1168 | ret = trace_seq_printf(s, "[%02d] ", iter->cpu); | |
1169 | if (!ret) | |
1170 | return 0; | |
1171 | ret = trace_seq_printf(s, "%5lu.%06lu: ", secs, usec_rem); | |
1172 | if (!ret) | |
1173 | return 0; | |
bc0c38d1 SR |
1174 | |
1175 | switch (entry->type) { | |
1176 | case TRACE_FN: | |
b3806b43 SR |
1177 | ret = seq_print_ip_sym(s, entry->fn.ip, sym_flags); |
1178 | if (!ret) | |
1179 | return 0; | |
bc0c38d1 SR |
1180 | if ((sym_flags & TRACE_ITER_PRINT_PARENT) && |
1181 | entry->fn.parent_ip) { | |
b3806b43 SR |
1182 | ret = trace_seq_printf(s, " <-"); |
1183 | if (!ret) | |
1184 | return 0; | |
1185 | ret = seq_print_ip_sym(s, entry->fn.parent_ip, | |
1186 | sym_flags); | |
1187 | if (!ret) | |
1188 | return 0; | |
bc0c38d1 | 1189 | } |
b3806b43 SR |
1190 | ret = trace_seq_printf(s, "\n"); |
1191 | if (!ret) | |
1192 | return 0; | |
bc0c38d1 SR |
1193 | break; |
1194 | case TRACE_CTX: | |
1195 | S = entry->ctx.prev_state < sizeof(state_to_char) ? | |
1196 | state_to_char[entry->ctx.prev_state] : 'X'; | |
b3806b43 SR |
1197 | ret = trace_seq_printf(s, " %d:%d:%c ==> %d:%d\n", |
1198 | entry->ctx.prev_pid, | |
1199 | entry->ctx.prev_prio, | |
1200 | S, | |
1201 | entry->ctx.next_pid, | |
1202 | entry->ctx.next_prio); | |
1203 | if (!ret) | |
1204 | return 0; | |
bc0c38d1 | 1205 | break; |
f0a920d5 IM |
1206 | case TRACE_SPECIAL: |
1207 | ret = trace_seq_printf(s, " %lx %lx %lx\n", | |
1208 | entry->special.arg1, | |
1209 | entry->special.arg2, | |
1210 | entry->special.arg3); | |
1211 | if (!ret) | |
1212 | return 0; | |
1213 | break; | |
bc0c38d1 | 1214 | } |
b3806b43 | 1215 | return 1; |
bc0c38d1 SR |
1216 | } |
1217 | ||
f9896bf3 IM |
1218 | static notrace int print_raw_fmt(struct trace_iterator *iter) |
1219 | { | |
1220 | struct trace_seq *s = &iter->seq; | |
1221 | struct trace_entry *entry; | |
1222 | int ret; | |
1223 | int S; | |
1224 | ||
1225 | entry = iter->ent; | |
1226 | ||
1227 | ret = trace_seq_printf(s, "%d %d %llu ", | |
1228 | entry->pid, iter->cpu, entry->t); | |
1229 | if (!ret) | |
1230 | return 0; | |
1231 | ||
1232 | switch (entry->type) { | |
1233 | case TRACE_FN: | |
1234 | ret = trace_seq_printf(s, "%x %x\n", | |
1235 | entry->fn.ip, entry->fn.parent_ip); | |
1236 | if (!ret) | |
1237 | return 0; | |
1238 | break; | |
1239 | case TRACE_CTX: | |
1240 | S = entry->ctx.prev_state < sizeof(state_to_char) ? | |
1241 | state_to_char[entry->ctx.prev_state] : 'X'; | |
1242 | ret = trace_seq_printf(s, "%d %d %c %d %d\n", | |
1243 | entry->ctx.prev_pid, | |
1244 | entry->ctx.prev_prio, | |
1245 | S, | |
1246 | entry->ctx.next_pid, | |
1247 | entry->ctx.next_prio); | |
1248 | if (!ret) | |
1249 | return 0; | |
1250 | break; | |
f0a920d5 IM |
1251 | case TRACE_SPECIAL: |
1252 | ret = trace_seq_printf(s, " %lx %lx %lx\n", | |
1253 | entry->special.arg1, | |
1254 | entry->special.arg2, | |
1255 | entry->special.arg3); | |
1256 | if (!ret) | |
1257 | return 0; | |
1258 | break; | |
f9896bf3 IM |
1259 | } |
1260 | return 1; | |
1261 | } | |
1262 | ||
cb0f12aa IM |
1263 | #define SEQ_PUT_FIELD_RET(s, x) \ |
1264 | do { \ | |
1265 | if (!trace_seq_putmem(s, &(x), sizeof(x))) \ | |
1266 | return 0; \ | |
1267 | } while (0) | |
1268 | ||
1269 | static notrace int print_bin_fmt(struct trace_iterator *iter) | |
1270 | { | |
1271 | struct trace_seq *s = &iter->seq; | |
1272 | struct trace_entry *entry; | |
1273 | ||
1274 | entry = iter->ent; | |
1275 | ||
1276 | SEQ_PUT_FIELD_RET(s, entry->pid); | |
1277 | SEQ_PUT_FIELD_RET(s, entry->cpu); | |
1278 | SEQ_PUT_FIELD_RET(s, entry->t); | |
1279 | ||
1280 | switch (entry->type) { | |
1281 | case TRACE_FN: | |
1282 | SEQ_PUT_FIELD_RET(s, entry->fn.ip); | |
1283 | SEQ_PUT_FIELD_RET(s, entry->fn.parent_ip); | |
1284 | break; | |
1285 | case TRACE_CTX: | |
1286 | SEQ_PUT_FIELD_RET(s, entry->ctx.prev_pid); | |
1287 | SEQ_PUT_FIELD_RET(s, entry->ctx.prev_prio); | |
1288 | SEQ_PUT_FIELD_RET(s, entry->ctx.prev_state); | |
1289 | SEQ_PUT_FIELD_RET(s, entry->ctx.next_pid); | |
1290 | SEQ_PUT_FIELD_RET(s, entry->ctx.next_prio); | |
1291 | break; | |
f0a920d5 IM |
1292 | case TRACE_SPECIAL: |
1293 | SEQ_PUT_FIELD_RET(s, entry->special.arg1); | |
1294 | SEQ_PUT_FIELD_RET(s, entry->special.arg2); | |
1295 | SEQ_PUT_FIELD_RET(s, entry->special.arg3); | |
1296 | break; | |
cb0f12aa IM |
1297 | } |
1298 | return 1; | |
1299 | } | |
1300 | ||
bc0c38d1 SR |
1301 | static int trace_empty(struct trace_iterator *iter) |
1302 | { | |
1303 | struct trace_array_cpu *data; | |
1304 | int cpu; | |
1305 | ||
1306 | for_each_possible_cpu(cpu) { | |
1307 | data = iter->tr->data[cpu]; | |
1308 | ||
b3806b43 SR |
1309 | if (head_page(data) && data->trace_idx && |
1310 | (data->trace_tail != data->trace_head || | |
1311 | data->trace_tail_idx != data->trace_head_idx)) | |
bc0c38d1 SR |
1312 | return 0; |
1313 | } | |
1314 | return 1; | |
1315 | } | |
1316 | ||
f9896bf3 IM |
1317 | static int print_trace_line(struct trace_iterator *iter) |
1318 | { | |
cb0f12aa IM |
1319 | if (trace_flags & TRACE_ITER_BIN) |
1320 | return print_bin_fmt(iter); | |
1321 | ||
f9896bf3 IM |
1322 | if (trace_flags & TRACE_ITER_RAW) |
1323 | return print_raw_fmt(iter); | |
1324 | ||
1325 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) | |
1326 | return print_lat_fmt(iter, iter->idx, iter->cpu); | |
1327 | ||
1328 | return print_trace_fmt(iter); | |
1329 | } | |
1330 | ||
bc0c38d1 SR |
1331 | static int s_show(struct seq_file *m, void *v) |
1332 | { | |
1333 | struct trace_iterator *iter = v; | |
1334 | ||
1335 | if (iter->ent == NULL) { | |
1336 | if (iter->tr) { | |
1337 | seq_printf(m, "# tracer: %s\n", iter->trace->name); | |
1338 | seq_puts(m, "#\n"); | |
1339 | } | |
1340 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) { | |
1341 | /* print nothing if the buffers are empty */ | |
1342 | if (trace_empty(iter)) | |
1343 | return 0; | |
1344 | print_trace_header(m, iter); | |
1345 | if (!(trace_flags & TRACE_ITER_VERBOSE)) | |
1346 | print_lat_help_header(m); | |
1347 | } else { | |
1348 | if (!(trace_flags & TRACE_ITER_VERBOSE)) | |
1349 | print_func_help_header(m); | |
1350 | } | |
1351 | } else { | |
f9896bf3 | 1352 | print_trace_line(iter); |
214023c3 | 1353 | trace_print_seq(m, &iter->seq); |
bc0c38d1 SR |
1354 | } |
1355 | ||
1356 | return 0; | |
1357 | } | |
1358 | ||
1359 | static struct seq_operations tracer_seq_ops = { | |
4bf39a94 IM |
1360 | .start = s_start, |
1361 | .next = s_next, | |
1362 | .stop = s_stop, | |
1363 | .show = s_show, | |
bc0c38d1 SR |
1364 | }; |
1365 | ||
1366 | static struct trace_iterator notrace * | |
1367 | __tracing_open(struct inode *inode, struct file *file, int *ret) | |
1368 | { | |
1369 | struct trace_iterator *iter; | |
1370 | ||
60a11774 SR |
1371 | if (tracing_disabled) { |
1372 | *ret = -ENODEV; | |
1373 | return NULL; | |
1374 | } | |
1375 | ||
bc0c38d1 SR |
1376 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); |
1377 | if (!iter) { | |
1378 | *ret = -ENOMEM; | |
1379 | goto out; | |
1380 | } | |
1381 | ||
1382 | mutex_lock(&trace_types_lock); | |
1383 | if (current_trace && current_trace->print_max) | |
1384 | iter->tr = &max_tr; | |
1385 | else | |
1386 | iter->tr = inode->i_private; | |
1387 | iter->trace = current_trace; | |
1388 | iter->pos = -1; | |
1389 | ||
1390 | /* TODO stop tracer */ | |
1391 | *ret = seq_open(file, &tracer_seq_ops); | |
1392 | if (!*ret) { | |
1393 | struct seq_file *m = file->private_data; | |
1394 | m->private = iter; | |
1395 | ||
1396 | /* stop the trace while dumping */ | |
1397 | if (iter->tr->ctrl) | |
1398 | tracer_enabled = 0; | |
1399 | ||
1400 | if (iter->trace && iter->trace->open) | |
1401 | iter->trace->open(iter); | |
1402 | } else { | |
1403 | kfree(iter); | |
1404 | iter = NULL; | |
1405 | } | |
1406 | mutex_unlock(&trace_types_lock); | |
1407 | ||
1408 | out: | |
1409 | return iter; | |
1410 | } | |
1411 | ||
1412 | int tracing_open_generic(struct inode *inode, struct file *filp) | |
1413 | { | |
60a11774 SR |
1414 | if (tracing_disabled) |
1415 | return -ENODEV; | |
1416 | ||
bc0c38d1 SR |
1417 | filp->private_data = inode->i_private; |
1418 | return 0; | |
1419 | } | |
1420 | ||
1421 | int tracing_release(struct inode *inode, struct file *file) | |
1422 | { | |
1423 | struct seq_file *m = (struct seq_file *)file->private_data; | |
1424 | struct trace_iterator *iter = m->private; | |
1425 | ||
1426 | mutex_lock(&trace_types_lock); | |
1427 | if (iter->trace && iter->trace->close) | |
1428 | iter->trace->close(iter); | |
1429 | ||
1430 | /* reenable tracing if it was previously enabled */ | |
1431 | if (iter->tr->ctrl) | |
1432 | tracer_enabled = 1; | |
1433 | mutex_unlock(&trace_types_lock); | |
1434 | ||
1435 | seq_release(inode, file); | |
1436 | kfree(iter); | |
1437 | return 0; | |
1438 | } | |
1439 | ||
1440 | static int tracing_open(struct inode *inode, struct file *file) | |
1441 | { | |
1442 | int ret; | |
1443 | ||
1444 | __tracing_open(inode, file, &ret); | |
1445 | ||
1446 | return ret; | |
1447 | } | |
1448 | ||
1449 | static int tracing_lt_open(struct inode *inode, struct file *file) | |
1450 | { | |
1451 | struct trace_iterator *iter; | |
1452 | int ret; | |
1453 | ||
1454 | iter = __tracing_open(inode, file, &ret); | |
1455 | ||
1456 | if (!ret) | |
1457 | iter->iter_flags |= TRACE_FILE_LAT_FMT; | |
1458 | ||
1459 | return ret; | |
1460 | } | |
1461 | ||
1462 | ||
4e3c3333 | 1463 | static notrace void * |
bc0c38d1 SR |
1464 | t_next(struct seq_file *m, void *v, loff_t *pos) |
1465 | { | |
1466 | struct tracer *t = m->private; | |
1467 | ||
1468 | (*pos)++; | |
1469 | ||
1470 | if (t) | |
1471 | t = t->next; | |
1472 | ||
1473 | m->private = t; | |
1474 | ||
1475 | return t; | |
1476 | } | |
1477 | ||
1478 | static void *t_start(struct seq_file *m, loff_t *pos) | |
1479 | { | |
1480 | struct tracer *t = m->private; | |
1481 | loff_t l = 0; | |
1482 | ||
1483 | mutex_lock(&trace_types_lock); | |
1484 | for (; t && l < *pos; t = t_next(m, t, &l)) | |
1485 | ; | |
1486 | ||
1487 | return t; | |
1488 | } | |
1489 | ||
1490 | static void t_stop(struct seq_file *m, void *p) | |
1491 | { | |
1492 | mutex_unlock(&trace_types_lock); | |
1493 | } | |
1494 | ||
1495 | static int t_show(struct seq_file *m, void *v) | |
1496 | { | |
1497 | struct tracer *t = v; | |
1498 | ||
1499 | if (!t) | |
1500 | return 0; | |
1501 | ||
1502 | seq_printf(m, "%s", t->name); | |
1503 | if (t->next) | |
1504 | seq_putc(m, ' '); | |
1505 | else | |
1506 | seq_putc(m, '\n'); | |
1507 | ||
1508 | return 0; | |
1509 | } | |
1510 | ||
1511 | static struct seq_operations show_traces_seq_ops = { | |
4bf39a94 IM |
1512 | .start = t_start, |
1513 | .next = t_next, | |
1514 | .stop = t_stop, | |
1515 | .show = t_show, | |
bc0c38d1 SR |
1516 | }; |
1517 | ||
1518 | static int show_traces_open(struct inode *inode, struct file *file) | |
1519 | { | |
1520 | int ret; | |
1521 | ||
60a11774 SR |
1522 | if (tracing_disabled) |
1523 | return -ENODEV; | |
1524 | ||
bc0c38d1 SR |
1525 | ret = seq_open(file, &show_traces_seq_ops); |
1526 | if (!ret) { | |
1527 | struct seq_file *m = file->private_data; | |
1528 | m->private = trace_types; | |
1529 | } | |
1530 | ||
1531 | return ret; | |
1532 | } | |
1533 | ||
1534 | static struct file_operations tracing_fops = { | |
4bf39a94 IM |
1535 | .open = tracing_open, |
1536 | .read = seq_read, | |
1537 | .llseek = seq_lseek, | |
1538 | .release = tracing_release, | |
bc0c38d1 SR |
1539 | }; |
1540 | ||
1541 | static struct file_operations tracing_lt_fops = { | |
4bf39a94 IM |
1542 | .open = tracing_lt_open, |
1543 | .read = seq_read, | |
1544 | .llseek = seq_lseek, | |
1545 | .release = tracing_release, | |
bc0c38d1 SR |
1546 | }; |
1547 | ||
1548 | static struct file_operations show_traces_fops = { | |
1549 | .open = show_traces_open, | |
1550 | .read = seq_read, | |
1551 | .release = seq_release, | |
1552 | }; | |
1553 | ||
1554 | static ssize_t | |
1555 | tracing_iter_ctrl_read(struct file *filp, char __user *ubuf, | |
1556 | size_t cnt, loff_t *ppos) | |
1557 | { | |
1558 | char *buf; | |
1559 | int r = 0; | |
1560 | int len = 0; | |
1561 | int i; | |
1562 | ||
1563 | /* calulate max size */ | |
1564 | for (i = 0; trace_options[i]; i++) { | |
1565 | len += strlen(trace_options[i]); | |
1566 | len += 3; /* "no" and space */ | |
1567 | } | |
1568 | ||
1569 | /* +2 for \n and \0 */ | |
1570 | buf = kmalloc(len + 2, GFP_KERNEL); | |
1571 | if (!buf) | |
1572 | return -ENOMEM; | |
1573 | ||
1574 | for (i = 0; trace_options[i]; i++) { | |
1575 | if (trace_flags & (1 << i)) | |
1576 | r += sprintf(buf + r, "%s ", trace_options[i]); | |
1577 | else | |
1578 | r += sprintf(buf + r, "no%s ", trace_options[i]); | |
1579 | } | |
1580 | ||
1581 | r += sprintf(buf + r, "\n"); | |
1582 | WARN_ON(r >= len + 2); | |
1583 | ||
1584 | r = simple_read_from_buffer(ubuf, cnt, ppos, | |
1585 | buf, r); | |
1586 | ||
1587 | kfree(buf); | |
1588 | ||
1589 | return r; | |
1590 | } | |
1591 | ||
1592 | static ssize_t | |
1593 | tracing_iter_ctrl_write(struct file *filp, const char __user *ubuf, | |
1594 | size_t cnt, loff_t *ppos) | |
1595 | { | |
1596 | char buf[64]; | |
1597 | char *cmp = buf; | |
1598 | int neg = 0; | |
1599 | int i; | |
1600 | ||
1601 | if (cnt > 63) | |
1602 | cnt = 63; | |
1603 | ||
1604 | if (copy_from_user(&buf, ubuf, cnt)) | |
1605 | return -EFAULT; | |
1606 | ||
1607 | buf[cnt] = 0; | |
1608 | ||
1609 | if (strncmp(buf, "no", 2) == 0) { | |
1610 | neg = 1; | |
1611 | cmp += 2; | |
1612 | } | |
1613 | ||
1614 | for (i = 0; trace_options[i]; i++) { | |
1615 | int len = strlen(trace_options[i]); | |
1616 | ||
1617 | if (strncmp(cmp, trace_options[i], len) == 0) { | |
1618 | if (neg) | |
1619 | trace_flags &= ~(1 << i); | |
1620 | else | |
1621 | trace_flags |= (1 << i); | |
1622 | break; | |
1623 | } | |
1624 | } | |
1625 | ||
1626 | filp->f_pos += cnt; | |
1627 | ||
1628 | return cnt; | |
1629 | } | |
1630 | ||
1631 | static struct file_operations tracing_iter_fops = { | |
1632 | .open = tracing_open_generic, | |
1633 | .read = tracing_iter_ctrl_read, | |
1634 | .write = tracing_iter_ctrl_write, | |
1635 | }; | |
1636 | ||
7bd2f24c IM |
1637 | static const char readme_msg[] = |
1638 | "tracing mini-HOWTO:\n\n" | |
1639 | "# mkdir /debug\n" | |
1640 | "# mount -t debugfs nodev /debug\n\n" | |
1641 | "# cat /debug/tracing/available_tracers\n" | |
1642 | "wakeup preemptirqsoff preemptoff irqsoff ftrace sched_switch none\n\n" | |
1643 | "# cat /debug/tracing/current_tracer\n" | |
1644 | "none\n" | |
1645 | "# echo sched_switch > /debug/tracing/current_tracer\n" | |
1646 | "# cat /debug/tracing/current_tracer\n" | |
1647 | "sched_switch\n" | |
1648 | "# cat /debug/tracing/iter_ctrl\n" | |
1649 | "noprint-parent nosym-offset nosym-addr noverbose\n" | |
1650 | "# echo print-parent > /debug/tracing/iter_ctrl\n" | |
1651 | "# echo 1 > /debug/tracing/tracing_enabled\n" | |
1652 | "# cat /debug/tracing/trace > /tmp/trace.txt\n" | |
1653 | "echo 0 > /debug/tracing/tracing_enabled\n" | |
1654 | ; | |
1655 | ||
1656 | static ssize_t | |
1657 | tracing_readme_read(struct file *filp, char __user *ubuf, | |
1658 | size_t cnt, loff_t *ppos) | |
1659 | { | |
1660 | return simple_read_from_buffer(ubuf, cnt, ppos, | |
1661 | readme_msg, strlen(readme_msg)); | |
1662 | } | |
1663 | ||
1664 | static struct file_operations tracing_readme_fops = { | |
1665 | .open = tracing_open_generic, | |
1666 | .read = tracing_readme_read, | |
1667 | }; | |
1668 | ||
1669 | ||
bc0c38d1 SR |
1670 | static ssize_t |
1671 | tracing_ctrl_read(struct file *filp, char __user *ubuf, | |
1672 | size_t cnt, loff_t *ppos) | |
1673 | { | |
1674 | struct trace_array *tr = filp->private_data; | |
1675 | char buf[64]; | |
1676 | int r; | |
1677 | ||
1678 | r = sprintf(buf, "%ld\n", tr->ctrl); | |
4e3c3333 | 1679 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
1680 | } |
1681 | ||
1682 | static ssize_t | |
1683 | tracing_ctrl_write(struct file *filp, const char __user *ubuf, | |
1684 | size_t cnt, loff_t *ppos) | |
1685 | { | |
1686 | struct trace_array *tr = filp->private_data; | |
1687 | long val; | |
1688 | char buf[64]; | |
1689 | ||
1690 | if (cnt > 63) | |
1691 | cnt = 63; | |
1692 | ||
1693 | if (copy_from_user(&buf, ubuf, cnt)) | |
1694 | return -EFAULT; | |
1695 | ||
1696 | buf[cnt] = 0; | |
1697 | ||
1698 | val = simple_strtoul(buf, NULL, 10); | |
1699 | ||
1700 | val = !!val; | |
1701 | ||
1702 | mutex_lock(&trace_types_lock); | |
1703 | if (tr->ctrl ^ val) { | |
1704 | if (val) | |
1705 | tracer_enabled = 1; | |
1706 | else | |
1707 | tracer_enabled = 0; | |
1708 | ||
1709 | tr->ctrl = val; | |
1710 | ||
1711 | if (current_trace && current_trace->ctrl_update) | |
1712 | current_trace->ctrl_update(tr); | |
1713 | } | |
1714 | mutex_unlock(&trace_types_lock); | |
1715 | ||
1716 | filp->f_pos += cnt; | |
1717 | ||
1718 | return cnt; | |
1719 | } | |
1720 | ||
1721 | static ssize_t | |
1722 | tracing_set_trace_read(struct file *filp, char __user *ubuf, | |
1723 | size_t cnt, loff_t *ppos) | |
1724 | { | |
1725 | char buf[max_tracer_type_len+2]; | |
1726 | int r; | |
1727 | ||
1728 | mutex_lock(&trace_types_lock); | |
1729 | if (current_trace) | |
1730 | r = sprintf(buf, "%s\n", current_trace->name); | |
1731 | else | |
1732 | r = sprintf(buf, "\n"); | |
1733 | mutex_unlock(&trace_types_lock); | |
1734 | ||
4bf39a94 | 1735 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
1736 | } |
1737 | ||
1738 | static ssize_t | |
1739 | tracing_set_trace_write(struct file *filp, const char __user *ubuf, | |
1740 | size_t cnt, loff_t *ppos) | |
1741 | { | |
1742 | struct trace_array *tr = &global_trace; | |
1743 | struct tracer *t; | |
1744 | char buf[max_tracer_type_len+1]; | |
1745 | int i; | |
1746 | ||
1747 | if (cnt > max_tracer_type_len) | |
1748 | cnt = max_tracer_type_len; | |
1749 | ||
1750 | if (copy_from_user(&buf, ubuf, cnt)) | |
1751 | return -EFAULT; | |
1752 | ||
1753 | buf[cnt] = 0; | |
1754 | ||
1755 | /* strip ending whitespace. */ | |
1756 | for (i = cnt - 1; i > 0 && isspace(buf[i]); i--) | |
1757 | buf[i] = 0; | |
1758 | ||
1759 | mutex_lock(&trace_types_lock); | |
1760 | for (t = trace_types; t; t = t->next) { | |
1761 | if (strcmp(t->name, buf) == 0) | |
1762 | break; | |
1763 | } | |
1764 | if (!t || t == current_trace) | |
1765 | goto out; | |
1766 | ||
1767 | if (current_trace && current_trace->reset) | |
1768 | current_trace->reset(tr); | |
1769 | ||
1770 | current_trace = t; | |
1771 | if (t->init) | |
1772 | t->init(tr); | |
1773 | ||
1774 | out: | |
1775 | mutex_unlock(&trace_types_lock); | |
1776 | ||
1777 | filp->f_pos += cnt; | |
1778 | ||
1779 | return cnt; | |
1780 | } | |
1781 | ||
1782 | static ssize_t | |
1783 | tracing_max_lat_read(struct file *filp, char __user *ubuf, | |
1784 | size_t cnt, loff_t *ppos) | |
1785 | { | |
1786 | unsigned long *ptr = filp->private_data; | |
1787 | char buf[64]; | |
1788 | int r; | |
1789 | ||
1790 | r = snprintf(buf, 64, "%ld\n", | |
1791 | *ptr == (unsigned long)-1 ? -1 : nsecs_to_usecs(*ptr)); | |
1792 | if (r > 64) | |
1793 | r = 64; | |
4bf39a94 | 1794 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
1795 | } |
1796 | ||
1797 | static ssize_t | |
1798 | tracing_max_lat_write(struct file *filp, const char __user *ubuf, | |
1799 | size_t cnt, loff_t *ppos) | |
1800 | { | |
1801 | long *ptr = filp->private_data; | |
1802 | long val; | |
1803 | char buf[64]; | |
1804 | ||
1805 | if (cnt > 63) | |
1806 | cnt = 63; | |
1807 | ||
1808 | if (copy_from_user(&buf, ubuf, cnt)) | |
1809 | return -EFAULT; | |
1810 | ||
1811 | buf[cnt] = 0; | |
1812 | ||
1813 | val = simple_strtoul(buf, NULL, 10); | |
1814 | ||
1815 | *ptr = val * 1000; | |
1816 | ||
1817 | return cnt; | |
1818 | } | |
1819 | ||
b3806b43 SR |
1820 | static atomic_t tracing_reader; |
1821 | ||
1822 | static int tracing_open_pipe(struct inode *inode, struct file *filp) | |
1823 | { | |
1824 | struct trace_iterator *iter; | |
1825 | ||
1826 | if (tracing_disabled) | |
1827 | return -ENODEV; | |
1828 | ||
1829 | /* We only allow for reader of the pipe */ | |
1830 | if (atomic_inc_return(&tracing_reader) != 1) { | |
1831 | atomic_dec(&tracing_reader); | |
1832 | return -EBUSY; | |
1833 | } | |
1834 | ||
1835 | /* create a buffer to store the information to pass to userspace */ | |
1836 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); | |
1837 | if (!iter) | |
1838 | return -ENOMEM; | |
1839 | ||
1840 | iter->tr = &global_trace; | |
1841 | ||
1842 | filp->private_data = iter; | |
1843 | ||
1844 | return 0; | |
1845 | } | |
1846 | ||
1847 | static int tracing_release_pipe(struct inode *inode, struct file *file) | |
1848 | { | |
1849 | struct trace_iterator *iter = file->private_data; | |
1850 | ||
1851 | kfree(iter); | |
1852 | atomic_dec(&tracing_reader); | |
1853 | ||
1854 | return 0; | |
1855 | } | |
1856 | ||
1857 | /* | |
1858 | * Consumer reader. | |
1859 | */ | |
1860 | static ssize_t | |
1861 | tracing_read_pipe(struct file *filp, char __user *ubuf, | |
1862 | size_t cnt, loff_t *ppos) | |
1863 | { | |
1864 | struct trace_iterator *iter = filp->private_data; | |
1865 | struct trace_array_cpu *data; | |
1866 | static cpumask_t mask; | |
b3806b43 SR |
1867 | static int start; |
1868 | unsigned long flags; | |
1869 | int read = 0; | |
1870 | int cpu; | |
1871 | int len; | |
1872 | int ret; | |
1873 | ||
1874 | /* return any leftover data */ | |
1875 | if (iter->seq.len > start) { | |
1876 | len = iter->seq.len - start; | |
1877 | if (cnt > len) | |
1878 | cnt = len; | |
1879 | ret = copy_to_user(ubuf, iter->seq.buffer + start, cnt); | |
1880 | if (ret) | |
1881 | cnt = -EFAULT; | |
1882 | ||
1883 | start += len; | |
1884 | ||
1885 | return cnt; | |
1886 | } | |
1887 | ||
1888 | trace_seq_reset(&iter->seq); | |
1889 | start = 0; | |
1890 | ||
1891 | while (trace_empty(iter)) { | |
1892 | /* | |
1893 | * This is a make-shift waitqueue. The reason we don't use | |
1894 | * an actual wait queue is because: | |
1895 | * 1) we only ever have one waiter | |
1896 | * 2) the tracing, traces all functions, we don't want | |
1897 | * the overhead of calling wake_up and friends | |
1898 | * (and tracing them too) | |
1899 | * Anyway, this is really very primitive wakeup. | |
1900 | */ | |
1901 | set_current_state(TASK_INTERRUPTIBLE); | |
1902 | iter->tr->waiter = current; | |
1903 | ||
1904 | /* sleep for one second, and try again. */ | |
1905 | schedule_timeout(HZ); | |
1906 | ||
1907 | iter->tr->waiter = NULL; | |
1908 | ||
1909 | if (signal_pending(current)) | |
1910 | return -EINTR; | |
1911 | ||
1912 | /* | |
1913 | * We block until we read something and tracing is disabled. | |
1914 | * We still block if tracing is disabled, but we have never | |
1915 | * read anything. This allows a user to cat this file, and | |
1916 | * then enable tracing. But after we have read something, | |
1917 | * we give an EOF when tracing is again disabled. | |
1918 | * | |
1919 | * iter->pos will be 0 if we haven't read anything. | |
1920 | */ | |
1921 | if (!tracer_enabled && iter->pos) | |
1922 | break; | |
1923 | ||
1924 | continue; | |
1925 | } | |
1926 | ||
1927 | /* stop when tracing is finished */ | |
1928 | if (trace_empty(iter)) | |
1929 | return 0; | |
1930 | ||
1931 | if (cnt >= PAGE_SIZE) | |
1932 | cnt = PAGE_SIZE - 1; | |
1933 | ||
1934 | memset(iter, 0, sizeof(*iter)); | |
1935 | iter->tr = &global_trace; | |
1936 | iter->pos = -1; | |
1937 | ||
1938 | /* | |
1939 | * We need to stop all tracing on all CPUS to read the | |
1940 | * the next buffer. This is a bit expensive, but is | |
1941 | * not done often. We fill all what we can read, | |
1942 | * and then release the locks again. | |
1943 | */ | |
1944 | ||
1945 | cpus_clear(mask); | |
1946 | local_irq_save(flags); | |
1947 | for_each_possible_cpu(cpu) { | |
1948 | data = iter->tr->data[cpu]; | |
1949 | ||
1950 | if (!head_page(data) || !data->trace_idx) | |
1951 | continue; | |
1952 | ||
1953 | atomic_inc(&data->disabled); | |
1954 | spin_lock(&data->lock); | |
1955 | cpu_set(cpu, mask); | |
1956 | } | |
1957 | ||
088b1e42 SR |
1958 | while (find_next_entry_inc(iter) != NULL) { |
1959 | int len = iter->seq.len; | |
1960 | ||
f9896bf3 | 1961 | ret = print_trace_line(iter); |
088b1e42 SR |
1962 | if (!ret) { |
1963 | /* don't print partial lines */ | |
1964 | iter->seq.len = len; | |
b3806b43 | 1965 | break; |
088b1e42 | 1966 | } |
b3806b43 SR |
1967 | |
1968 | trace_consume(iter); | |
1969 | ||
1970 | if (iter->seq.len >= cnt) | |
1971 | break; | |
b3806b43 SR |
1972 | } |
1973 | ||
d4c5a2f5 | 1974 | for_each_cpu_mask(cpu, mask) { |
b3806b43 | 1975 | data = iter->tr->data[cpu]; |
b3806b43 SR |
1976 | spin_unlock(&data->lock); |
1977 | atomic_dec(&data->disabled); | |
1978 | } | |
1979 | local_irq_restore(flags); | |
1980 | ||
1981 | /* Now copy what we have to the user */ | |
1982 | read = iter->seq.len; | |
1983 | if (read > cnt) | |
1984 | read = cnt; | |
1985 | ||
1986 | ret = copy_to_user(ubuf, iter->seq.buffer, read); | |
1987 | ||
1988 | if (read < iter->seq.len) | |
1989 | start = read; | |
1990 | else | |
1991 | trace_seq_reset(&iter->seq); | |
1992 | ||
1993 | if (ret) | |
1994 | read = -EFAULT; | |
1995 | ||
1996 | return read; | |
1997 | } | |
1998 | ||
bc0c38d1 | 1999 | static struct file_operations tracing_max_lat_fops = { |
4bf39a94 IM |
2000 | .open = tracing_open_generic, |
2001 | .read = tracing_max_lat_read, | |
2002 | .write = tracing_max_lat_write, | |
bc0c38d1 SR |
2003 | }; |
2004 | ||
2005 | static struct file_operations tracing_ctrl_fops = { | |
4bf39a94 IM |
2006 | .open = tracing_open_generic, |
2007 | .read = tracing_ctrl_read, | |
2008 | .write = tracing_ctrl_write, | |
bc0c38d1 SR |
2009 | }; |
2010 | ||
2011 | static struct file_operations set_tracer_fops = { | |
4bf39a94 IM |
2012 | .open = tracing_open_generic, |
2013 | .read = tracing_set_trace_read, | |
2014 | .write = tracing_set_trace_write, | |
bc0c38d1 SR |
2015 | }; |
2016 | ||
b3806b43 | 2017 | static struct file_operations tracing_pipe_fops = { |
4bf39a94 IM |
2018 | .open = tracing_open_pipe, |
2019 | .read = tracing_read_pipe, | |
2020 | .release = tracing_release_pipe, | |
b3806b43 SR |
2021 | }; |
2022 | ||
bc0c38d1 SR |
2023 | #ifdef CONFIG_DYNAMIC_FTRACE |
2024 | ||
2025 | static ssize_t | |
2026 | tracing_read_long(struct file *filp, char __user *ubuf, | |
2027 | size_t cnt, loff_t *ppos) | |
2028 | { | |
2029 | unsigned long *p = filp->private_data; | |
2030 | char buf[64]; | |
2031 | int r; | |
2032 | ||
2033 | r = sprintf(buf, "%ld\n", *p); | |
4bf39a94 IM |
2034 | |
2035 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
bc0c38d1 SR |
2036 | } |
2037 | ||
2038 | static struct file_operations tracing_read_long_fops = { | |
4bf39a94 IM |
2039 | .open = tracing_open_generic, |
2040 | .read = tracing_read_long, | |
bc0c38d1 SR |
2041 | }; |
2042 | #endif | |
2043 | ||
2044 | static struct dentry *d_tracer; | |
2045 | ||
2046 | struct dentry *tracing_init_dentry(void) | |
2047 | { | |
2048 | static int once; | |
2049 | ||
2050 | if (d_tracer) | |
2051 | return d_tracer; | |
2052 | ||
2053 | d_tracer = debugfs_create_dir("tracing", NULL); | |
2054 | ||
2055 | if (!d_tracer && !once) { | |
2056 | once = 1; | |
2057 | pr_warning("Could not create debugfs directory 'tracing'\n"); | |
2058 | return NULL; | |
2059 | } | |
2060 | ||
2061 | return d_tracer; | |
2062 | } | |
2063 | ||
60a11774 SR |
2064 | #ifdef CONFIG_FTRACE_SELFTEST |
2065 | /* Let selftest have access to static functions in this file */ | |
2066 | #include "trace_selftest.c" | |
2067 | #endif | |
2068 | ||
bc0c38d1 SR |
2069 | static __init void tracer_init_debugfs(void) |
2070 | { | |
2071 | struct dentry *d_tracer; | |
2072 | struct dentry *entry; | |
2073 | ||
2074 | d_tracer = tracing_init_dentry(); | |
2075 | ||
2076 | entry = debugfs_create_file("tracing_enabled", 0644, d_tracer, | |
2077 | &global_trace, &tracing_ctrl_fops); | |
2078 | if (!entry) | |
2079 | pr_warning("Could not create debugfs 'tracing_enabled' entry\n"); | |
2080 | ||
2081 | entry = debugfs_create_file("iter_ctrl", 0644, d_tracer, | |
2082 | NULL, &tracing_iter_fops); | |
2083 | if (!entry) | |
2084 | pr_warning("Could not create debugfs 'iter_ctrl' entry\n"); | |
2085 | ||
2086 | entry = debugfs_create_file("latency_trace", 0444, d_tracer, | |
2087 | &global_trace, &tracing_lt_fops); | |
2088 | if (!entry) | |
2089 | pr_warning("Could not create debugfs 'latency_trace' entry\n"); | |
2090 | ||
2091 | entry = debugfs_create_file("trace", 0444, d_tracer, | |
2092 | &global_trace, &tracing_fops); | |
2093 | if (!entry) | |
2094 | pr_warning("Could not create debugfs 'trace' entry\n"); | |
2095 | ||
2096 | entry = debugfs_create_file("available_tracers", 0444, d_tracer, | |
2097 | &global_trace, &show_traces_fops); | |
2098 | if (!entry) | |
2099 | pr_warning("Could not create debugfs 'trace' entry\n"); | |
2100 | ||
2101 | entry = debugfs_create_file("current_tracer", 0444, d_tracer, | |
2102 | &global_trace, &set_tracer_fops); | |
2103 | if (!entry) | |
2104 | pr_warning("Could not create debugfs 'trace' entry\n"); | |
2105 | ||
2106 | entry = debugfs_create_file("tracing_max_latency", 0644, d_tracer, | |
2107 | &tracing_max_latency, | |
2108 | &tracing_max_lat_fops); | |
2109 | if (!entry) | |
2110 | pr_warning("Could not create debugfs " | |
2111 | "'tracing_max_latency' entry\n"); | |
2112 | ||
2113 | entry = debugfs_create_file("tracing_thresh", 0644, d_tracer, | |
2114 | &tracing_thresh, &tracing_max_lat_fops); | |
2115 | if (!entry) | |
2116 | pr_warning("Could not create debugfs " | |
2117 | "'tracing_threash' entry\n"); | |
7bd2f24c IM |
2118 | entry = debugfs_create_file("README", 0644, d_tracer, |
2119 | NULL, &tracing_readme_fops); | |
2120 | if (!entry) | |
2121 | pr_warning("Could not create debugfs 'README' entry\n"); | |
2122 | ||
b3806b43 SR |
2123 | entry = debugfs_create_file("trace_pipe", 0644, d_tracer, |
2124 | NULL, &tracing_pipe_fops); | |
2125 | if (!entry) | |
2126 | pr_warning("Could not create debugfs " | |
2127 | "'tracing_threash' entry\n"); | |
bc0c38d1 SR |
2128 | |
2129 | #ifdef CONFIG_DYNAMIC_FTRACE | |
2130 | entry = debugfs_create_file("dyn_ftrace_total_info", 0444, d_tracer, | |
2131 | &ftrace_update_tot_cnt, | |
2132 | &tracing_read_long_fops); | |
2133 | if (!entry) | |
2134 | pr_warning("Could not create debugfs " | |
2135 | "'dyn_ftrace_total_info' entry\n"); | |
2136 | #endif | |
2137 | } | |
2138 | ||
2139 | /* dummy trace to disable tracing */ | |
2140 | static struct tracer no_tracer __read_mostly = | |
2141 | { | |
4bf39a94 | 2142 | .name = "none", |
bc0c38d1 SR |
2143 | }; |
2144 | ||
4c11d7ae | 2145 | static int trace_alloc_page(void) |
bc0c38d1 | 2146 | { |
4c11d7ae | 2147 | struct trace_array_cpu *data; |
4c11d7ae SR |
2148 | struct page *page, *tmp; |
2149 | LIST_HEAD(pages); | |
c7aafc54 | 2150 | void *array; |
4c11d7ae SR |
2151 | int i; |
2152 | ||
2153 | /* first allocate a page for each CPU */ | |
2154 | for_each_possible_cpu(i) { | |
2155 | array = (void *)__get_free_page(GFP_KERNEL); | |
2156 | if (array == NULL) { | |
2157 | printk(KERN_ERR "tracer: failed to allocate page" | |
2158 | "for trace buffer!\n"); | |
2159 | goto free_pages; | |
2160 | } | |
2161 | ||
2162 | page = virt_to_page(array); | |
2163 | list_add(&page->lru, &pages); | |
2164 | ||
2165 | /* Only allocate if we are actually using the max trace */ | |
2166 | #ifdef CONFIG_TRACER_MAX_TRACE | |
2167 | array = (void *)__get_free_page(GFP_KERNEL); | |
2168 | if (array == NULL) { | |
2169 | printk(KERN_ERR "tracer: failed to allocate page" | |
2170 | "for trace buffer!\n"); | |
2171 | goto free_pages; | |
2172 | } | |
2173 | page = virt_to_page(array); | |
2174 | list_add(&page->lru, &pages); | |
2175 | #endif | |
2176 | } | |
2177 | ||
2178 | /* Now that we successfully allocate a page per CPU, add them */ | |
2179 | for_each_possible_cpu(i) { | |
2180 | data = global_trace.data[i]; | |
b3806b43 | 2181 | spin_lock_init(&data->lock); |
d4c5a2f5 | 2182 | lockdep_set_class(&data->lock, &data->lock_key); |
4c11d7ae | 2183 | page = list_entry(pages.next, struct page, lru); |
c7aafc54 | 2184 | list_del_init(&page->lru); |
4c11d7ae SR |
2185 | list_add_tail(&page->lru, &data->trace_pages); |
2186 | ClearPageLRU(page); | |
2187 | ||
2188 | #ifdef CONFIG_TRACER_MAX_TRACE | |
2189 | data = max_tr.data[i]; | |
b3806b43 | 2190 | spin_lock_init(&data->lock); |
d4c5a2f5 | 2191 | lockdep_set_class(&data->lock, &data->lock_key); |
4c11d7ae | 2192 | page = list_entry(pages.next, struct page, lru); |
c7aafc54 | 2193 | list_del_init(&page->lru); |
4c11d7ae SR |
2194 | list_add_tail(&page->lru, &data->trace_pages); |
2195 | SetPageLRU(page); | |
2196 | #endif | |
2197 | } | |
2198 | global_trace.entries += ENTRIES_PER_PAGE; | |
2199 | ||
2200 | return 0; | |
2201 | ||
2202 | free_pages: | |
2203 | list_for_each_entry_safe(page, tmp, &pages, lru) { | |
c7aafc54 | 2204 | list_del_init(&page->lru); |
4c11d7ae SR |
2205 | __free_page(page); |
2206 | } | |
2207 | return -ENOMEM; | |
bc0c38d1 SR |
2208 | } |
2209 | ||
2210 | __init static int tracer_alloc_buffers(void) | |
2211 | { | |
4c11d7ae SR |
2212 | struct trace_array_cpu *data; |
2213 | void *array; | |
2214 | struct page *page; | |
2215 | int pages = 0; | |
60a11774 | 2216 | int ret = -ENOMEM; |
bc0c38d1 SR |
2217 | int i; |
2218 | ||
26994ead SR |
2219 | global_trace.ctrl = tracer_enabled; |
2220 | ||
4c11d7ae | 2221 | /* Allocate the first page for all buffers */ |
bc0c38d1 | 2222 | for_each_possible_cpu(i) { |
4c11d7ae | 2223 | data = global_trace.data[i] = &per_cpu(global_trace_cpu, i); |
bc0c38d1 SR |
2224 | max_tr.data[i] = &per_cpu(max_data, i); |
2225 | ||
4c11d7ae | 2226 | array = (void *)__get_free_page(GFP_KERNEL); |
bc0c38d1 | 2227 | if (array == NULL) { |
4c11d7ae SR |
2228 | printk(KERN_ERR "tracer: failed to allocate page" |
2229 | "for trace buffer!\n"); | |
bc0c38d1 SR |
2230 | goto free_buffers; |
2231 | } | |
4c11d7ae SR |
2232 | |
2233 | /* set the array to the list */ | |
2234 | INIT_LIST_HEAD(&data->trace_pages); | |
2235 | page = virt_to_page(array); | |
2236 | list_add(&page->lru, &data->trace_pages); | |
2237 | /* use the LRU flag to differentiate the two buffers */ | |
2238 | ClearPageLRU(page); | |
bc0c38d1 SR |
2239 | |
2240 | /* Only allocate if we are actually using the max trace */ | |
2241 | #ifdef CONFIG_TRACER_MAX_TRACE | |
4c11d7ae | 2242 | array = (void *)__get_free_page(GFP_KERNEL); |
bc0c38d1 | 2243 | if (array == NULL) { |
4c11d7ae SR |
2244 | printk(KERN_ERR "tracer: failed to allocate page" |
2245 | "for trace buffer!\n"); | |
bc0c38d1 SR |
2246 | goto free_buffers; |
2247 | } | |
4c11d7ae SR |
2248 | |
2249 | INIT_LIST_HEAD(&max_tr.data[i]->trace_pages); | |
2250 | page = virt_to_page(array); | |
2251 | list_add(&page->lru, &max_tr.data[i]->trace_pages); | |
2252 | SetPageLRU(page); | |
bc0c38d1 SR |
2253 | #endif |
2254 | } | |
2255 | ||
2256 | /* | |
2257 | * Since we allocate by orders of pages, we may be able to | |
2258 | * round up a bit. | |
2259 | */ | |
4c11d7ae | 2260 | global_trace.entries = ENTRIES_PER_PAGE; |
4c11d7ae SR |
2261 | pages++; |
2262 | ||
2263 | while (global_trace.entries < trace_nr_entries) { | |
2264 | if (trace_alloc_page()) | |
2265 | break; | |
2266 | pages++; | |
2267 | } | |
89b2f978 | 2268 | max_tr.entries = global_trace.entries; |
bc0c38d1 | 2269 | |
4c11d7ae SR |
2270 | pr_info("tracer: %d pages allocated for %ld", |
2271 | pages, trace_nr_entries); | |
bc0c38d1 SR |
2272 | pr_info(" entries of %ld bytes\n", (long)TRACE_ENTRY_SIZE); |
2273 | pr_info(" actual entries %ld\n", global_trace.entries); | |
2274 | ||
2275 | tracer_init_debugfs(); | |
2276 | ||
2277 | trace_init_cmdlines(); | |
2278 | ||
2279 | register_tracer(&no_tracer); | |
2280 | current_trace = &no_tracer; | |
2281 | ||
60a11774 SR |
2282 | /* All seems OK, enable tracing */ |
2283 | tracing_disabled = 0; | |
2284 | ||
bc0c38d1 SR |
2285 | return 0; |
2286 | ||
2287 | free_buffers: | |
2288 | for (i-- ; i >= 0; i--) { | |
4c11d7ae | 2289 | struct page *page, *tmp; |
bc0c38d1 SR |
2290 | struct trace_array_cpu *data = global_trace.data[i]; |
2291 | ||
c7aafc54 | 2292 | if (data) { |
4c11d7ae SR |
2293 | list_for_each_entry_safe(page, tmp, |
2294 | &data->trace_pages, lru) { | |
c7aafc54 | 2295 | list_del_init(&page->lru); |
4c11d7ae SR |
2296 | __free_page(page); |
2297 | } | |
bc0c38d1 SR |
2298 | } |
2299 | ||
2300 | #ifdef CONFIG_TRACER_MAX_TRACE | |
2301 | data = max_tr.data[i]; | |
c7aafc54 | 2302 | if (data) { |
4c11d7ae SR |
2303 | list_for_each_entry_safe(page, tmp, |
2304 | &data->trace_pages, lru) { | |
c7aafc54 | 2305 | list_del_init(&page->lru); |
4c11d7ae SR |
2306 | __free_page(page); |
2307 | } | |
bc0c38d1 SR |
2308 | } |
2309 | #endif | |
2310 | } | |
60a11774 | 2311 | return ret; |
bc0c38d1 | 2312 | } |
60a11774 | 2313 | fs_initcall(tracer_alloc_buffers); |