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, |
5e3ca0ec IM |
106 | TRACE_ITER_HEX = 0x20, |
107 | TRACE_ITER_BIN = 0x40, | |
bc0c38d1 SR |
108 | }; |
109 | ||
110 | #define TRACE_ITER_SYM_MASK \ | |
111 | (TRACE_ITER_PRINT_PARENT|TRACE_ITER_SYM_OFFSET|TRACE_ITER_SYM_ADDR) | |
112 | ||
113 | /* These must match the bit postions above */ | |
114 | static const char *trace_options[] = { | |
115 | "print-parent", | |
116 | "sym-offset", | |
117 | "sym-addr", | |
118 | "verbose", | |
f9896bf3 | 119 | "raw", |
5e3ca0ec | 120 | "hex", |
cb0f12aa | 121 | "bin", |
bc0c38d1 SR |
122 | NULL |
123 | }; | |
124 | ||
125 | static unsigned trace_flags; | |
126 | ||
4c11d7ae | 127 | static DEFINE_SPINLOCK(ftrace_max_lock); |
bc0c38d1 SR |
128 | |
129 | /* | |
130 | * Copy the new maximum trace into the separate maximum-trace | |
131 | * structure. (this way the maximum trace is permanently saved, | |
132 | * for later retrieval via /debugfs/tracing/latency_trace) | |
133 | */ | |
4e3c3333 | 134 | static notrace void |
bc0c38d1 SR |
135 | __update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) |
136 | { | |
137 | struct trace_array_cpu *data = tr->data[cpu]; | |
138 | ||
139 | max_tr.cpu = cpu; | |
140 | max_tr.time_start = data->preempt_timestamp; | |
141 | ||
142 | data = max_tr.data[cpu]; | |
143 | data->saved_latency = tracing_max_latency; | |
144 | ||
145 | memcpy(data->comm, tsk->comm, TASK_COMM_LEN); | |
146 | data->pid = tsk->pid; | |
147 | data->uid = tsk->uid; | |
148 | data->nice = tsk->static_prio - 20 - MAX_RT_PRIO; | |
149 | data->policy = tsk->policy; | |
150 | data->rt_priority = tsk->rt_priority; | |
151 | ||
152 | /* record this tasks comm */ | |
153 | tracing_record_cmdline(current); | |
154 | } | |
155 | ||
c7aafc54 IM |
156 | void check_pages(struct trace_array_cpu *data) |
157 | { | |
158 | struct page *page, *tmp; | |
159 | ||
160 | BUG_ON(data->trace_pages.next->prev != &data->trace_pages); | |
161 | BUG_ON(data->trace_pages.prev->next != &data->trace_pages); | |
162 | ||
163 | list_for_each_entry_safe(page, tmp, &data->trace_pages, lru) { | |
164 | BUG_ON(page->lru.next->prev != &page->lru); | |
165 | BUG_ON(page->lru.prev->next != &page->lru); | |
166 | } | |
167 | } | |
168 | ||
169 | void *head_page(struct trace_array_cpu *data) | |
170 | { | |
171 | struct page *page; | |
172 | ||
173 | check_pages(data); | |
174 | if (list_empty(&data->trace_pages)) | |
175 | return NULL; | |
176 | ||
177 | page = list_entry(data->trace_pages.next, struct page, lru); | |
178 | BUG_ON(&page->lru == &data->trace_pages); | |
179 | ||
180 | return page_address(page); | |
181 | } | |
182 | ||
214023c3 SR |
183 | static notrace int |
184 | trace_seq_printf(struct trace_seq *s, const char *fmt, ...) | |
185 | { | |
186 | int len = (PAGE_SIZE - 1) - s->len; | |
187 | va_list ap; | |
b3806b43 | 188 | int ret; |
214023c3 SR |
189 | |
190 | if (!len) | |
191 | return 0; | |
192 | ||
193 | va_start(ap, fmt); | |
b3806b43 | 194 | ret = vsnprintf(s->buffer + s->len, len, fmt, ap); |
214023c3 SR |
195 | va_end(ap); |
196 | ||
b3806b43 SR |
197 | /* If we can't write it all, don't bother writing anything */ |
198 | if (ret > len) | |
199 | return 0; | |
200 | ||
201 | s->len += ret; | |
214023c3 SR |
202 | |
203 | return len; | |
204 | } | |
205 | ||
206 | static notrace int | |
207 | trace_seq_puts(struct trace_seq *s, const char *str) | |
208 | { | |
209 | int len = strlen(str); | |
210 | ||
211 | if (len > ((PAGE_SIZE - 1) - s->len)) | |
b3806b43 | 212 | return 0; |
214023c3 SR |
213 | |
214 | memcpy(s->buffer + s->len, str, len); | |
215 | s->len += len; | |
216 | ||
217 | return len; | |
218 | } | |
219 | ||
220 | static notrace int | |
221 | trace_seq_putc(struct trace_seq *s, unsigned char c) | |
222 | { | |
223 | if (s->len >= (PAGE_SIZE - 1)) | |
224 | return 0; | |
225 | ||
226 | s->buffer[s->len++] = c; | |
227 | ||
228 | return 1; | |
229 | } | |
230 | ||
cb0f12aa IM |
231 | static notrace int |
232 | trace_seq_putmem(struct trace_seq *s, void *mem, size_t len) | |
233 | { | |
234 | if (len > ((PAGE_SIZE - 1) - s->len)) | |
235 | return 0; | |
236 | ||
237 | memcpy(s->buffer + s->len, mem, len); | |
238 | s->len += len; | |
239 | ||
240 | return len; | |
241 | } | |
242 | ||
5e3ca0ec IM |
243 | #define HEX_CHARS 17 |
244 | ||
245 | static notrace int | |
246 | trace_seq_putmem_hex(struct trace_seq *s, void *mem, size_t len) | |
247 | { | |
248 | unsigned char hex[HEX_CHARS]; | |
249 | unsigned char *data; | |
250 | unsigned char byte; | |
251 | int i, j; | |
252 | ||
253 | BUG_ON(len >= HEX_CHARS); | |
254 | ||
255 | data = mem; | |
256 | ||
257 | #ifdef __BIG_ENDIAN | |
258 | for (i = 0, j = 0; i < len; i++) { | |
259 | #else | |
260 | for (i = len-1, j = 0; i >= 0; i--) { | |
261 | #endif | |
262 | byte = data[i]; | |
263 | ||
264 | hex[j] = byte & 0x0f; | |
265 | if (hex[j] >= 10) | |
266 | hex[j] += 'a' - 10; | |
267 | else | |
268 | hex[j] += '0'; | |
269 | j++; | |
270 | ||
271 | hex[j] = byte >> 4; | |
272 | if (hex[j] >= 10) | |
273 | hex[j] += 'a' - 10; | |
274 | else | |
275 | hex[j] += '0'; | |
276 | j++; | |
277 | } | |
278 | hex[j] = ' '; | |
279 | j++; | |
280 | ||
281 | return trace_seq_putmem(s, hex, j); | |
282 | } | |
283 | ||
214023c3 SR |
284 | static notrace void |
285 | trace_seq_reset(struct trace_seq *s) | |
286 | { | |
287 | s->len = 0; | |
288 | } | |
289 | ||
290 | static notrace void | |
291 | trace_print_seq(struct seq_file *m, struct trace_seq *s) | |
292 | { | |
293 | int len = s->len >= PAGE_SIZE ? PAGE_SIZE - 1 : s->len; | |
294 | ||
295 | s->buffer[len] = 0; | |
296 | seq_puts(m, s->buffer); | |
297 | ||
298 | trace_seq_reset(s); | |
299 | } | |
300 | ||
c7aafc54 IM |
301 | notrace static void |
302 | flip_trace(struct trace_array_cpu *tr1, struct trace_array_cpu *tr2) | |
303 | { | |
304 | struct list_head flip_pages; | |
305 | ||
306 | INIT_LIST_HEAD(&flip_pages); | |
307 | ||
93a588f4 | 308 | memcpy(&tr1->trace_head_idx, &tr2->trace_head_idx, |
c7aafc54 | 309 | sizeof(struct trace_array_cpu) - |
93a588f4 | 310 | offsetof(struct trace_array_cpu, trace_head_idx)); |
c7aafc54 IM |
311 | |
312 | check_pages(tr1); | |
313 | check_pages(tr2); | |
314 | list_splice_init(&tr1->trace_pages, &flip_pages); | |
315 | list_splice_init(&tr2->trace_pages, &tr1->trace_pages); | |
316 | list_splice_init(&flip_pages, &tr2->trace_pages); | |
317 | BUG_ON(!list_empty(&flip_pages)); | |
318 | check_pages(tr1); | |
319 | check_pages(tr2); | |
320 | } | |
321 | ||
bc0c38d1 SR |
322 | notrace void |
323 | update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) | |
324 | { | |
325 | struct trace_array_cpu *data; | |
bc0c38d1 SR |
326 | int i; |
327 | ||
4c11d7ae SR |
328 | WARN_ON_ONCE(!irqs_disabled()); |
329 | spin_lock(&ftrace_max_lock); | |
bc0c38d1 SR |
330 | /* clear out all the previous traces */ |
331 | for_each_possible_cpu(i) { | |
332 | data = tr->data[i]; | |
c7aafc54 | 333 | flip_trace(max_tr.data[i], data); |
89b2f978 | 334 | tracing_reset(data); |
bc0c38d1 SR |
335 | } |
336 | ||
337 | __update_max_tr(tr, tsk, cpu); | |
4c11d7ae | 338 | spin_unlock(&ftrace_max_lock); |
bc0c38d1 SR |
339 | } |
340 | ||
341 | /** | |
342 | * update_max_tr_single - only copy one trace over, and reset the rest | |
343 | * @tr - tracer | |
344 | * @tsk - task with the latency | |
345 | * @cpu - the cpu of the buffer to copy. | |
346 | */ | |
347 | notrace void | |
348 | update_max_tr_single(struct trace_array *tr, struct task_struct *tsk, int cpu) | |
349 | { | |
350 | struct trace_array_cpu *data = tr->data[cpu]; | |
bc0c38d1 SR |
351 | int i; |
352 | ||
4c11d7ae SR |
353 | WARN_ON_ONCE(!irqs_disabled()); |
354 | spin_lock(&ftrace_max_lock); | |
bc0c38d1 SR |
355 | for_each_possible_cpu(i) |
356 | tracing_reset(max_tr.data[i]); | |
357 | ||
c7aafc54 | 358 | flip_trace(max_tr.data[cpu], data); |
89b2f978 | 359 | tracing_reset(data); |
bc0c38d1 SR |
360 | |
361 | __update_max_tr(tr, tsk, cpu); | |
4c11d7ae | 362 | spin_unlock(&ftrace_max_lock); |
bc0c38d1 SR |
363 | } |
364 | ||
365 | int register_tracer(struct tracer *type) | |
366 | { | |
367 | struct tracer *t; | |
368 | int len; | |
369 | int ret = 0; | |
370 | ||
371 | if (!type->name) { | |
372 | pr_info("Tracer must have a name\n"); | |
373 | return -1; | |
374 | } | |
375 | ||
376 | mutex_lock(&trace_types_lock); | |
377 | for (t = trace_types; t; t = t->next) { | |
378 | if (strcmp(type->name, t->name) == 0) { | |
379 | /* already found */ | |
380 | pr_info("Trace %s already registered\n", | |
381 | type->name); | |
382 | ret = -1; | |
383 | goto out; | |
384 | } | |
385 | } | |
386 | ||
60a11774 SR |
387 | #ifdef CONFIG_FTRACE_STARTUP_TEST |
388 | if (type->selftest) { | |
389 | struct tracer *saved_tracer = current_trace; | |
390 | struct trace_array_cpu *data; | |
391 | struct trace_array *tr = &global_trace; | |
392 | int saved_ctrl = tr->ctrl; | |
393 | int i; | |
394 | /* | |
395 | * Run a selftest on this tracer. | |
396 | * Here we reset the trace buffer, and set the current | |
397 | * tracer to be this tracer. The tracer can then run some | |
398 | * internal tracing to verify that everything is in order. | |
399 | * If we fail, we do not register this tracer. | |
400 | */ | |
401 | for_each_possible_cpu(i) { | |
60a11774 | 402 | data = tr->data[i]; |
c7aafc54 IM |
403 | if (!head_page(data)) |
404 | continue; | |
60a11774 SR |
405 | tracing_reset(data); |
406 | } | |
407 | current_trace = type; | |
408 | tr->ctrl = 0; | |
409 | /* the test is responsible for initializing and enabling */ | |
410 | pr_info("Testing tracer %s: ", type->name); | |
411 | ret = type->selftest(type, tr); | |
412 | /* the test is responsible for resetting too */ | |
413 | current_trace = saved_tracer; | |
414 | tr->ctrl = saved_ctrl; | |
415 | if (ret) { | |
416 | printk(KERN_CONT "FAILED!\n"); | |
417 | goto out; | |
418 | } | |
1d4db00a SR |
419 | /* Only reset on passing, to avoid touching corrupted buffers */ |
420 | for_each_possible_cpu(i) { | |
421 | data = tr->data[i]; | |
422 | if (!head_page(data)) | |
423 | continue; | |
424 | tracing_reset(data); | |
425 | } | |
60a11774 SR |
426 | printk(KERN_CONT "PASSED\n"); |
427 | } | |
428 | #endif | |
429 | ||
bc0c38d1 SR |
430 | type->next = trace_types; |
431 | trace_types = type; | |
432 | len = strlen(type->name); | |
433 | if (len > max_tracer_type_len) | |
434 | max_tracer_type_len = len; | |
60a11774 | 435 | |
bc0c38d1 SR |
436 | out: |
437 | mutex_unlock(&trace_types_lock); | |
438 | ||
439 | return ret; | |
440 | } | |
441 | ||
442 | void unregister_tracer(struct tracer *type) | |
443 | { | |
444 | struct tracer **t; | |
445 | int len; | |
446 | ||
447 | mutex_lock(&trace_types_lock); | |
448 | for (t = &trace_types; *t; t = &(*t)->next) { | |
449 | if (*t == type) | |
450 | goto found; | |
451 | } | |
452 | pr_info("Trace %s not registered\n", type->name); | |
453 | goto out; | |
454 | ||
455 | found: | |
456 | *t = (*t)->next; | |
457 | if (strlen(type->name) != max_tracer_type_len) | |
458 | goto out; | |
459 | ||
460 | max_tracer_type_len = 0; | |
461 | for (t = &trace_types; *t; t = &(*t)->next) { | |
462 | len = strlen((*t)->name); | |
463 | if (len > max_tracer_type_len) | |
464 | max_tracer_type_len = len; | |
465 | } | |
466 | out: | |
467 | mutex_unlock(&trace_types_lock); | |
468 | } | |
469 | ||
4e3c3333 | 470 | notrace void tracing_reset(struct trace_array_cpu *data) |
bc0c38d1 SR |
471 | { |
472 | data->trace_idx = 0; | |
93a588f4 SR |
473 | data->trace_head = data->trace_tail = head_page(data); |
474 | data->trace_head_idx = 0; | |
475 | data->trace_tail_idx = 0; | |
bc0c38d1 SR |
476 | } |
477 | ||
bc0c38d1 SR |
478 | #define SAVED_CMDLINES 128 |
479 | static unsigned map_pid_to_cmdline[PID_MAX_DEFAULT+1]; | |
480 | static unsigned map_cmdline_to_pid[SAVED_CMDLINES]; | |
481 | static char saved_cmdlines[SAVED_CMDLINES][TASK_COMM_LEN]; | |
482 | static int cmdline_idx; | |
483 | static DEFINE_SPINLOCK(trace_cmdline_lock); | |
484 | atomic_t trace_record_cmdline_disabled; | |
485 | ||
486 | static void trace_init_cmdlines(void) | |
487 | { | |
488 | memset(&map_pid_to_cmdline, -1, sizeof(map_pid_to_cmdline)); | |
489 | memset(&map_cmdline_to_pid, -1, sizeof(map_cmdline_to_pid)); | |
490 | cmdline_idx = 0; | |
491 | } | |
492 | ||
493 | notrace void trace_stop_cmdline_recording(void); | |
494 | ||
4e3c3333 | 495 | static notrace void trace_save_cmdline(struct task_struct *tsk) |
bc0c38d1 SR |
496 | { |
497 | unsigned map; | |
498 | unsigned idx; | |
499 | ||
500 | if (!tsk->pid || unlikely(tsk->pid > PID_MAX_DEFAULT)) | |
501 | return; | |
502 | ||
503 | /* | |
504 | * It's not the end of the world if we don't get | |
505 | * the lock, but we also don't want to spin | |
506 | * nor do we want to disable interrupts, | |
507 | * so if we miss here, then better luck next time. | |
508 | */ | |
509 | if (!spin_trylock(&trace_cmdline_lock)) | |
510 | return; | |
511 | ||
512 | idx = map_pid_to_cmdline[tsk->pid]; | |
513 | if (idx >= SAVED_CMDLINES) { | |
514 | idx = (cmdline_idx + 1) % SAVED_CMDLINES; | |
515 | ||
516 | map = map_cmdline_to_pid[idx]; | |
517 | if (map <= PID_MAX_DEFAULT) | |
518 | map_pid_to_cmdline[map] = (unsigned)-1; | |
519 | ||
520 | map_pid_to_cmdline[tsk->pid] = idx; | |
521 | ||
522 | cmdline_idx = idx; | |
523 | } | |
524 | ||
525 | memcpy(&saved_cmdlines[idx], tsk->comm, TASK_COMM_LEN); | |
526 | ||
527 | spin_unlock(&trace_cmdline_lock); | |
528 | } | |
529 | ||
530 | static notrace char *trace_find_cmdline(int pid) | |
531 | { | |
532 | char *cmdline = "<...>"; | |
533 | unsigned map; | |
534 | ||
535 | if (!pid) | |
536 | return "<idle>"; | |
537 | ||
538 | if (pid > PID_MAX_DEFAULT) | |
539 | goto out; | |
540 | ||
541 | map = map_pid_to_cmdline[pid]; | |
542 | if (map >= SAVED_CMDLINES) | |
543 | goto out; | |
544 | ||
545 | cmdline = saved_cmdlines[map]; | |
546 | ||
547 | out: | |
548 | return cmdline; | |
549 | } | |
550 | ||
551 | notrace void tracing_record_cmdline(struct task_struct *tsk) | |
552 | { | |
553 | if (atomic_read(&trace_record_cmdline_disabled)) | |
554 | return; | |
555 | ||
556 | trace_save_cmdline(tsk); | |
557 | } | |
558 | ||
93a588f4 SR |
559 | static inline notrace struct list_head * |
560 | trace_next_list(struct trace_array_cpu *data, struct list_head *next) | |
561 | { | |
562 | /* | |
563 | * Roundrobin - but skip the head (which is not a real page): | |
564 | */ | |
565 | next = next->next; | |
566 | if (unlikely(next == &data->trace_pages)) | |
567 | next = next->next; | |
568 | BUG_ON(next == &data->trace_pages); | |
569 | ||
570 | return next; | |
571 | } | |
572 | ||
573 | static inline notrace void * | |
574 | trace_next_page(struct trace_array_cpu *data, void *addr) | |
575 | { | |
576 | struct list_head *next; | |
577 | struct page *page; | |
578 | ||
579 | page = virt_to_page(addr); | |
580 | ||
581 | next = trace_next_list(data, &page->lru); | |
582 | page = list_entry(next, struct page, lru); | |
583 | ||
584 | return page_address(page); | |
585 | } | |
586 | ||
bc0c38d1 | 587 | static inline notrace struct trace_entry * |
c7aafc54 | 588 | tracing_get_trace_entry(struct trace_array *tr, struct trace_array_cpu *data) |
bc0c38d1 SR |
589 | { |
590 | unsigned long idx, idx_next; | |
591 | struct trace_entry *entry; | |
592 | ||
4c11d7ae | 593 | data->trace_idx++; |
93a588f4 | 594 | idx = data->trace_head_idx; |
bc0c38d1 SR |
595 | idx_next = idx + 1; |
596 | ||
c7aafc54 IM |
597 | BUG_ON(idx * TRACE_ENTRY_SIZE >= PAGE_SIZE); |
598 | ||
93a588f4 | 599 | entry = data->trace_head + idx * TRACE_ENTRY_SIZE; |
4c11d7ae SR |
600 | |
601 | if (unlikely(idx_next >= ENTRIES_PER_PAGE)) { | |
93a588f4 | 602 | data->trace_head = trace_next_page(data, data->trace_head); |
bc0c38d1 SR |
603 | idx_next = 0; |
604 | } | |
605 | ||
93a588f4 SR |
606 | if (data->trace_head == data->trace_tail && |
607 | idx_next == data->trace_tail_idx) { | |
608 | /* overrun */ | |
609 | data->trace_tail_idx++; | |
610 | if (data->trace_tail_idx >= ENTRIES_PER_PAGE) { | |
611 | data->trace_tail = | |
612 | trace_next_page(data, data->trace_tail); | |
613 | data->trace_tail_idx = 0; | |
614 | } | |
615 | } | |
616 | ||
617 | data->trace_head_idx = idx_next; | |
bc0c38d1 SR |
618 | |
619 | return entry; | |
620 | } | |
621 | ||
622 | static inline notrace void | |
c7aafc54 | 623 | tracing_generic_entry_update(struct trace_entry *entry, unsigned long flags) |
bc0c38d1 SR |
624 | { |
625 | struct task_struct *tsk = current; | |
626 | unsigned long pc; | |
627 | ||
628 | pc = preempt_count(); | |
629 | ||
c7aafc54 IM |
630 | entry->preempt_count = pc & 0xff; |
631 | entry->pid = tsk->pid; | |
750ed1a4 | 632 | entry->t = ftrace_now(raw_smp_processor_id()); |
bc0c38d1 SR |
633 | entry->flags = (irqs_disabled_flags(flags) ? TRACE_FLAG_IRQS_OFF : 0) | |
634 | ((pc & HARDIRQ_MASK) ? TRACE_FLAG_HARDIRQ : 0) | | |
635 | ((pc & SOFTIRQ_MASK) ? TRACE_FLAG_SOFTIRQ : 0) | | |
636 | (need_resched() ? TRACE_FLAG_NEED_RESCHED : 0); | |
637 | } | |
638 | ||
639 | notrace void | |
2e0f5761 IM |
640 | __ftrace(struct trace_array *tr, struct trace_array_cpu *data, |
641 | unsigned long ip, unsigned long parent_ip, unsigned long flags) | |
bc0c38d1 SR |
642 | { |
643 | struct trace_entry *entry; | |
dcb6308f | 644 | unsigned long irq_flags; |
bc0c38d1 | 645 | |
dcb6308f | 646 | spin_lock_irqsave(&data->lock, irq_flags); |
c7aafc54 | 647 | entry = tracing_get_trace_entry(tr, data); |
bc0c38d1 | 648 | tracing_generic_entry_update(entry, flags); |
c7aafc54 IM |
649 | entry->type = TRACE_FN; |
650 | entry->fn.ip = ip; | |
651 | entry->fn.parent_ip = parent_ip; | |
dcb6308f | 652 | spin_unlock_irqrestore(&data->lock, irq_flags); |
bc0c38d1 SR |
653 | } |
654 | ||
2e0f5761 IM |
655 | notrace void |
656 | ftrace(struct trace_array *tr, struct trace_array_cpu *data, | |
657 | unsigned long ip, unsigned long parent_ip, unsigned long flags) | |
658 | { | |
659 | if (likely(!atomic_read(&data->disabled))) | |
660 | __ftrace(tr, data, ip, parent_ip, flags); | |
661 | } | |
662 | ||
f0a920d5 IM |
663 | notrace void |
664 | trace_special(struct trace_array *tr, struct trace_array_cpu *data, | |
665 | unsigned long arg1, unsigned long arg2, unsigned long arg3) | |
666 | { | |
667 | struct trace_entry *entry; | |
dcb6308f | 668 | unsigned long irq_flags; |
f0a920d5 | 669 | |
dcb6308f | 670 | spin_lock_irqsave(&data->lock, irq_flags); |
f0a920d5 IM |
671 | entry = tracing_get_trace_entry(tr, data); |
672 | tracing_generic_entry_update(entry, 0); | |
673 | entry->type = TRACE_SPECIAL; | |
674 | entry->special.arg1 = arg1; | |
675 | entry->special.arg2 = arg2; | |
676 | entry->special.arg3 = arg3; | |
dcb6308f | 677 | spin_unlock_irqrestore(&data->lock, irq_flags); |
f0a920d5 IM |
678 | } |
679 | ||
bc0c38d1 SR |
680 | notrace void |
681 | tracing_sched_switch_trace(struct trace_array *tr, | |
682 | struct trace_array_cpu *data, | |
683 | struct task_struct *prev, struct task_struct *next, | |
684 | unsigned long flags) | |
685 | { | |
686 | struct trace_entry *entry; | |
dcb6308f | 687 | unsigned long irq_flags; |
bc0c38d1 | 688 | |
dcb6308f | 689 | spin_lock_irqsave(&data->lock, irq_flags); |
c7aafc54 | 690 | entry = tracing_get_trace_entry(tr, data); |
bc0c38d1 SR |
691 | tracing_generic_entry_update(entry, flags); |
692 | entry->type = TRACE_CTX; | |
693 | entry->ctx.prev_pid = prev->pid; | |
694 | entry->ctx.prev_prio = prev->prio; | |
695 | entry->ctx.prev_state = prev->state; | |
696 | entry->ctx.next_pid = next->pid; | |
697 | entry->ctx.next_prio = next->prio; | |
dcb6308f | 698 | spin_unlock_irqrestore(&data->lock, irq_flags); |
bc0c38d1 SR |
699 | } |
700 | ||
2e0f5761 IM |
701 | #ifdef CONFIG_FTRACE |
702 | static notrace void | |
703 | function_trace_call(unsigned long ip, unsigned long parent_ip) | |
704 | { | |
705 | struct trace_array *tr = &global_trace; | |
706 | struct trace_array_cpu *data; | |
707 | unsigned long flags; | |
708 | long disabled; | |
709 | int cpu; | |
710 | ||
711 | if (unlikely(!tracer_enabled)) | |
712 | return; | |
713 | ||
714 | local_irq_save(flags); | |
715 | cpu = raw_smp_processor_id(); | |
716 | data = tr->data[cpu]; | |
717 | disabled = atomic_inc_return(&data->disabled); | |
718 | ||
719 | if (likely(disabled == 1)) | |
720 | __ftrace(tr, data, ip, parent_ip, flags); | |
721 | ||
722 | atomic_dec(&data->disabled); | |
723 | local_irq_restore(flags); | |
724 | } | |
725 | ||
726 | static struct ftrace_ops trace_ops __read_mostly = | |
727 | { | |
728 | .func = function_trace_call, | |
729 | }; | |
730 | ||
731 | notrace void tracing_start_function_trace(void) | |
732 | { | |
733 | register_ftrace_function(&trace_ops); | |
734 | } | |
735 | ||
736 | notrace void tracing_stop_function_trace(void) | |
737 | { | |
738 | unregister_ftrace_function(&trace_ops); | |
739 | } | |
740 | #endif | |
741 | ||
bc0c38d1 SR |
742 | enum trace_file_type { |
743 | TRACE_FILE_LAT_FMT = 1, | |
744 | }; | |
745 | ||
746 | static struct trace_entry * | |
4c11d7ae SR |
747 | trace_entry_idx(struct trace_array *tr, struct trace_array_cpu *data, |
748 | struct trace_iterator *iter, int cpu) | |
bc0c38d1 | 749 | { |
4c11d7ae SR |
750 | struct page *page; |
751 | struct trace_entry *array; | |
bc0c38d1 | 752 | |
4c11d7ae | 753 | if (iter->next_idx[cpu] >= tr->entries || |
b3806b43 SR |
754 | iter->next_idx[cpu] >= data->trace_idx || |
755 | (data->trace_head == data->trace_tail && | |
756 | data->trace_head_idx == data->trace_tail_idx)) | |
bc0c38d1 SR |
757 | return NULL; |
758 | ||
4c11d7ae | 759 | if (!iter->next_page[cpu]) { |
93a588f4 SR |
760 | /* Initialize the iterator for this cpu trace buffer */ |
761 | WARN_ON(!data->trace_tail); | |
762 | page = virt_to_page(data->trace_tail); | |
763 | iter->next_page[cpu] = &page->lru; | |
764 | iter->next_page_idx[cpu] = data->trace_tail_idx; | |
4c11d7ae | 765 | } |
bc0c38d1 | 766 | |
4c11d7ae | 767 | page = list_entry(iter->next_page[cpu], struct page, lru); |
c7aafc54 IM |
768 | BUG_ON(&data->trace_pages == &page->lru); |
769 | ||
4c11d7ae SR |
770 | array = page_address(page); |
771 | ||
93a588f4 | 772 | WARN_ON(iter->next_page_idx[cpu] >= ENTRIES_PER_PAGE); |
4c11d7ae | 773 | return &array[iter->next_page_idx[cpu]]; |
bc0c38d1 SR |
774 | } |
775 | ||
2e0f5761 | 776 | static struct trace_entry * notrace |
bc0c38d1 SR |
777 | find_next_entry(struct trace_iterator *iter, int *ent_cpu) |
778 | { | |
779 | struct trace_array *tr = iter->tr; | |
780 | struct trace_entry *ent, *next = NULL; | |
781 | int next_cpu = -1; | |
782 | int cpu; | |
783 | ||
784 | for_each_possible_cpu(cpu) { | |
c7aafc54 | 785 | if (!head_page(tr->data[cpu])) |
bc0c38d1 | 786 | continue; |
4c11d7ae | 787 | ent = trace_entry_idx(tr, tr->data[cpu], iter, cpu); |
cdd31cd2 IM |
788 | /* |
789 | * Pick the entry with the smallest timestamp: | |
790 | */ | |
791 | if (ent && (!next || ent->t < next->t)) { | |
bc0c38d1 SR |
792 | next = ent; |
793 | next_cpu = cpu; | |
794 | } | |
795 | } | |
796 | ||
797 | if (ent_cpu) | |
798 | *ent_cpu = next_cpu; | |
799 | ||
800 | return next; | |
801 | } | |
802 | ||
8c523a9d | 803 | static notrace void trace_iterator_increment(struct trace_iterator *iter) |
bc0c38d1 | 804 | { |
b3806b43 SR |
805 | iter->idx++; |
806 | iter->next_idx[iter->cpu]++; | |
807 | iter->next_page_idx[iter->cpu]++; | |
8c523a9d | 808 | |
b3806b43 SR |
809 | if (iter->next_page_idx[iter->cpu] >= ENTRIES_PER_PAGE) { |
810 | struct trace_array_cpu *data = iter->tr->data[iter->cpu]; | |
bc0c38d1 | 811 | |
b3806b43 SR |
812 | iter->next_page_idx[iter->cpu] = 0; |
813 | iter->next_page[iter->cpu] = | |
814 | trace_next_list(data, iter->next_page[iter->cpu]); | |
815 | } | |
816 | } | |
bc0c38d1 | 817 | |
8c523a9d | 818 | static notrace void trace_consume(struct trace_iterator *iter) |
b3806b43 SR |
819 | { |
820 | struct trace_array_cpu *data = iter->tr->data[iter->cpu]; | |
821 | ||
822 | data->trace_tail_idx++; | |
823 | if (data->trace_tail_idx >= ENTRIES_PER_PAGE) { | |
824 | data->trace_tail = trace_next_page(data, data->trace_tail); | |
825 | data->trace_tail_idx = 0; | |
826 | } | |
4e3c3333 | 827 | |
b3806b43 SR |
828 | /* Check if we empty it, then reset the index */ |
829 | if (data->trace_head == data->trace_tail && | |
830 | data->trace_head_idx == data->trace_tail_idx) | |
831 | data->trace_idx = 0; | |
b3806b43 SR |
832 | } |
833 | ||
8c523a9d | 834 | static notrace void *find_next_entry_inc(struct trace_iterator *iter) |
b3806b43 SR |
835 | { |
836 | struct trace_entry *next; | |
837 | int next_cpu = -1; | |
838 | ||
839 | next = find_next_entry(iter, &next_cpu); | |
93a588f4 | 840 | |
4e3c3333 IM |
841 | iter->prev_ent = iter->ent; |
842 | iter->prev_cpu = iter->cpu; | |
843 | ||
bc0c38d1 SR |
844 | iter->ent = next; |
845 | iter->cpu = next_cpu; | |
846 | ||
b3806b43 SR |
847 | if (next) |
848 | trace_iterator_increment(iter); | |
849 | ||
bc0c38d1 SR |
850 | return next ? iter : NULL; |
851 | } | |
852 | ||
4e3c3333 | 853 | static notrace void *s_next(struct seq_file *m, void *v, loff_t *pos) |
bc0c38d1 SR |
854 | { |
855 | struct trace_iterator *iter = m->private; | |
bc0c38d1 SR |
856 | void *last_ent = iter->ent; |
857 | int i = (int)*pos; | |
4e3c3333 | 858 | void *ent; |
bc0c38d1 SR |
859 | |
860 | (*pos)++; | |
861 | ||
862 | /* can't go backwards */ | |
863 | if (iter->idx > i) | |
864 | return NULL; | |
865 | ||
866 | if (iter->idx < 0) | |
867 | ent = find_next_entry_inc(iter); | |
868 | else | |
869 | ent = iter; | |
870 | ||
871 | while (ent && iter->idx < i) | |
872 | ent = find_next_entry_inc(iter); | |
873 | ||
874 | iter->pos = *pos; | |
875 | ||
876 | if (last_ent && !ent) | |
877 | seq_puts(m, "\n\nvim:ft=help\n"); | |
878 | ||
879 | return ent; | |
880 | } | |
881 | ||
882 | static void *s_start(struct seq_file *m, loff_t *pos) | |
883 | { | |
884 | struct trace_iterator *iter = m->private; | |
885 | void *p = NULL; | |
886 | loff_t l = 0; | |
887 | int i; | |
888 | ||
889 | mutex_lock(&trace_types_lock); | |
890 | ||
891 | if (!current_trace || current_trace != iter->trace) | |
892 | return NULL; | |
893 | ||
894 | atomic_inc(&trace_record_cmdline_disabled); | |
895 | ||
896 | /* let the tracer grab locks here if needed */ | |
897 | if (current_trace->start) | |
898 | current_trace->start(iter); | |
899 | ||
900 | if (*pos != iter->pos) { | |
901 | iter->ent = NULL; | |
902 | iter->cpu = 0; | |
903 | iter->idx = -1; | |
4e3c3333 IM |
904 | iter->prev_ent = NULL; |
905 | iter->prev_cpu = -1; | |
bc0c38d1 | 906 | |
4c11d7ae | 907 | for_each_possible_cpu(i) { |
bc0c38d1 | 908 | iter->next_idx[i] = 0; |
4c11d7ae SR |
909 | iter->next_page[i] = NULL; |
910 | } | |
bc0c38d1 SR |
911 | |
912 | for (p = iter; p && l < *pos; p = s_next(m, p, &l)) | |
913 | ; | |
914 | ||
915 | } else { | |
4c11d7ae | 916 | l = *pos - 1; |
bc0c38d1 SR |
917 | p = s_next(m, p, &l); |
918 | } | |
919 | ||
920 | return p; | |
921 | } | |
922 | ||
923 | static void s_stop(struct seq_file *m, void *p) | |
924 | { | |
925 | struct trace_iterator *iter = m->private; | |
926 | ||
927 | atomic_dec(&trace_record_cmdline_disabled); | |
928 | ||
929 | /* let the tracer release locks here if needed */ | |
930 | if (current_trace && current_trace == iter->trace && iter->trace->stop) | |
931 | iter->trace->stop(iter); | |
932 | ||
933 | mutex_unlock(&trace_types_lock); | |
934 | } | |
935 | ||
b3806b43 | 936 | static int |
214023c3 | 937 | seq_print_sym_short(struct trace_seq *s, const char *fmt, unsigned long address) |
bc0c38d1 SR |
938 | { |
939 | #ifdef CONFIG_KALLSYMS | |
940 | char str[KSYM_SYMBOL_LEN]; | |
941 | ||
942 | kallsyms_lookup(address, NULL, NULL, NULL, str); | |
943 | ||
b3806b43 | 944 | return trace_seq_printf(s, fmt, str); |
bc0c38d1 | 945 | #endif |
b3806b43 | 946 | return 1; |
bc0c38d1 SR |
947 | } |
948 | ||
b3806b43 | 949 | static int |
214023c3 SR |
950 | seq_print_sym_offset(struct trace_seq *s, const char *fmt, |
951 | unsigned long address) | |
bc0c38d1 SR |
952 | { |
953 | #ifdef CONFIG_KALLSYMS | |
954 | char str[KSYM_SYMBOL_LEN]; | |
955 | ||
956 | sprint_symbol(str, address); | |
b3806b43 | 957 | return trace_seq_printf(s, fmt, str); |
bc0c38d1 | 958 | #endif |
b3806b43 | 959 | return 1; |
bc0c38d1 SR |
960 | } |
961 | ||
962 | #ifndef CONFIG_64BIT | |
963 | # define IP_FMT "%08lx" | |
964 | #else | |
965 | # define IP_FMT "%016lx" | |
966 | #endif | |
967 | ||
b3806b43 | 968 | static notrace int |
214023c3 | 969 | seq_print_ip_sym(struct trace_seq *s, unsigned long ip, unsigned long sym_flags) |
bc0c38d1 | 970 | { |
b3806b43 SR |
971 | int ret; |
972 | ||
973 | if (!ip) | |
974 | return trace_seq_printf(s, "0"); | |
bc0c38d1 SR |
975 | |
976 | if (sym_flags & TRACE_ITER_SYM_OFFSET) | |
b3806b43 | 977 | ret = seq_print_sym_offset(s, "%s", ip); |
bc0c38d1 | 978 | else |
b3806b43 SR |
979 | ret = seq_print_sym_short(s, "%s", ip); |
980 | ||
981 | if (!ret) | |
982 | return 0; | |
bc0c38d1 SR |
983 | |
984 | if (sym_flags & TRACE_ITER_SYM_ADDR) | |
b3806b43 SR |
985 | ret = trace_seq_printf(s, " <" IP_FMT ">", ip); |
986 | return ret; | |
bc0c38d1 SR |
987 | } |
988 | ||
4e3c3333 | 989 | static notrace void print_lat_help_header(struct seq_file *m) |
bc0c38d1 SR |
990 | { |
991 | seq_puts(m, "# _------=> CPU# \n"); | |
992 | seq_puts(m, "# / _-----=> irqs-off \n"); | |
993 | seq_puts(m, "# | / _----=> need-resched \n"); | |
994 | seq_puts(m, "# || / _---=> hardirq/softirq \n"); | |
995 | seq_puts(m, "# ||| / _--=> preempt-depth \n"); | |
996 | seq_puts(m, "# |||| / \n"); | |
997 | seq_puts(m, "# ||||| delay \n"); | |
998 | seq_puts(m, "# cmd pid ||||| time | caller \n"); | |
999 | seq_puts(m, "# \\ / ||||| \\ | / \n"); | |
1000 | } | |
1001 | ||
4e3c3333 | 1002 | static notrace void print_func_help_header(struct seq_file *m) |
bc0c38d1 SR |
1003 | { |
1004 | seq_puts(m, "# TASK-PID CPU# TIMESTAMP FUNCTION\n"); | |
1005 | seq_puts(m, "# | | | | |\n"); | |
1006 | } | |
1007 | ||
1008 | ||
4e3c3333 | 1009 | static notrace void |
bc0c38d1 SR |
1010 | print_trace_header(struct seq_file *m, struct trace_iterator *iter) |
1011 | { | |
1012 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); | |
1013 | struct trace_array *tr = iter->tr; | |
1014 | struct trace_array_cpu *data = tr->data[tr->cpu]; | |
1015 | struct tracer *type = current_trace; | |
4c11d7ae SR |
1016 | unsigned long total = 0; |
1017 | unsigned long entries = 0; | |
bc0c38d1 SR |
1018 | int cpu; |
1019 | const char *name = "preemption"; | |
1020 | ||
1021 | if (type) | |
1022 | name = type->name; | |
1023 | ||
1024 | for_each_possible_cpu(cpu) { | |
c7aafc54 | 1025 | if (head_page(tr->data[cpu])) { |
4c11d7ae SR |
1026 | total += tr->data[cpu]->trace_idx; |
1027 | if (tr->data[cpu]->trace_idx > tr->entries) | |
bc0c38d1 | 1028 | entries += tr->entries; |
4c11d7ae | 1029 | else |
bc0c38d1 SR |
1030 | entries += tr->data[cpu]->trace_idx; |
1031 | } | |
1032 | } | |
1033 | ||
1034 | seq_printf(m, "%s latency trace v1.1.5 on %s\n", | |
1035 | name, UTS_RELEASE); | |
1036 | seq_puts(m, "-----------------------------------" | |
1037 | "---------------------------------\n"); | |
1038 | seq_printf(m, " latency: %lu us, #%lu/%lu, CPU#%d |" | |
1039 | " (M:%s VP:%d, KP:%d, SP:%d HP:%d", | |
57f50be1 | 1040 | nsecs_to_usecs(data->saved_latency), |
bc0c38d1 | 1041 | entries, |
4c11d7ae | 1042 | total, |
bc0c38d1 SR |
1043 | tr->cpu, |
1044 | #if defined(CONFIG_PREEMPT_NONE) | |
1045 | "server", | |
1046 | #elif defined(CONFIG_PREEMPT_VOLUNTARY) | |
1047 | "desktop", | |
1048 | #elif defined(CONFIG_PREEMPT_DESKTOP) | |
1049 | "preempt", | |
1050 | #else | |
1051 | "unknown", | |
1052 | #endif | |
1053 | /* These are reserved for later use */ | |
1054 | 0, 0, 0, 0); | |
1055 | #ifdef CONFIG_SMP | |
1056 | seq_printf(m, " #P:%d)\n", num_online_cpus()); | |
1057 | #else | |
1058 | seq_puts(m, ")\n"); | |
1059 | #endif | |
1060 | seq_puts(m, " -----------------\n"); | |
1061 | seq_printf(m, " | task: %.16s-%d " | |
1062 | "(uid:%d nice:%ld policy:%ld rt_prio:%ld)\n", | |
1063 | data->comm, data->pid, data->uid, data->nice, | |
1064 | data->policy, data->rt_priority); | |
1065 | seq_puts(m, " -----------------\n"); | |
1066 | ||
1067 | if (data->critical_start) { | |
1068 | seq_puts(m, " => started at: "); | |
214023c3 SR |
1069 | seq_print_ip_sym(&iter->seq, data->critical_start, sym_flags); |
1070 | trace_print_seq(m, &iter->seq); | |
bc0c38d1 | 1071 | seq_puts(m, "\n => ended at: "); |
214023c3 SR |
1072 | seq_print_ip_sym(&iter->seq, data->critical_end, sym_flags); |
1073 | trace_print_seq(m, &iter->seq); | |
bc0c38d1 SR |
1074 | seq_puts(m, "\n"); |
1075 | } | |
1076 | ||
1077 | seq_puts(m, "\n"); | |
1078 | } | |
1079 | ||
4e3c3333 | 1080 | static notrace void |
214023c3 | 1081 | lat_print_generic(struct trace_seq *s, struct trace_entry *entry, int cpu) |
bc0c38d1 SR |
1082 | { |
1083 | int hardirq, softirq; | |
1084 | char *comm; | |
1085 | ||
1086 | comm = trace_find_cmdline(entry->pid); | |
1087 | ||
214023c3 SR |
1088 | trace_seq_printf(s, "%8.8s-%-5d ", comm, entry->pid); |
1089 | trace_seq_printf(s, "%d", cpu); | |
1090 | trace_seq_printf(s, "%c%c", | |
1091 | (entry->flags & TRACE_FLAG_IRQS_OFF) ? 'd' : '.', | |
1092 | ((entry->flags & TRACE_FLAG_NEED_RESCHED) ? 'N' : '.')); | |
bc0c38d1 SR |
1093 | |
1094 | hardirq = entry->flags & TRACE_FLAG_HARDIRQ; | |
1095 | softirq = entry->flags & TRACE_FLAG_SOFTIRQ; | |
1096 | if (hardirq && softirq) | |
214023c3 | 1097 | trace_seq_putc(s, 'H'); |
bc0c38d1 SR |
1098 | else { |
1099 | if (hardirq) | |
214023c3 | 1100 | trace_seq_putc(s, 'h'); |
bc0c38d1 SR |
1101 | else { |
1102 | if (softirq) | |
214023c3 | 1103 | trace_seq_putc(s, 's'); |
bc0c38d1 | 1104 | else |
214023c3 | 1105 | trace_seq_putc(s, '.'); |
bc0c38d1 SR |
1106 | } |
1107 | } | |
1108 | ||
1109 | if (entry->preempt_count) | |
214023c3 | 1110 | trace_seq_printf(s, "%x", entry->preempt_count); |
bc0c38d1 | 1111 | else |
214023c3 | 1112 | trace_seq_puts(s, "."); |
bc0c38d1 SR |
1113 | } |
1114 | ||
1115 | unsigned long preempt_mark_thresh = 100; | |
1116 | ||
4e3c3333 | 1117 | static notrace void |
214023c3 | 1118 | lat_print_timestamp(struct trace_seq *s, unsigned long long abs_usecs, |
bc0c38d1 SR |
1119 | unsigned long rel_usecs) |
1120 | { | |
214023c3 | 1121 | trace_seq_printf(s, " %4lldus", abs_usecs); |
bc0c38d1 | 1122 | if (rel_usecs > preempt_mark_thresh) |
214023c3 | 1123 | trace_seq_puts(s, "!: "); |
bc0c38d1 | 1124 | else if (rel_usecs > 1) |
214023c3 | 1125 | trace_seq_puts(s, "+: "); |
bc0c38d1 | 1126 | else |
214023c3 | 1127 | trace_seq_puts(s, " : "); |
bc0c38d1 SR |
1128 | } |
1129 | ||
1130 | static const char state_to_char[] = TASK_STATE_TO_CHAR_STR; | |
1131 | ||
f9896bf3 | 1132 | static notrace int |
214023c3 | 1133 | print_lat_fmt(struct trace_iterator *iter, unsigned int trace_idx, int cpu) |
bc0c38d1 | 1134 | { |
214023c3 | 1135 | struct trace_seq *s = &iter->seq; |
bc0c38d1 SR |
1136 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); |
1137 | struct trace_entry *next_entry = find_next_entry(iter, NULL); | |
1138 | unsigned long verbose = (trace_flags & TRACE_ITER_VERBOSE); | |
1139 | struct trace_entry *entry = iter->ent; | |
1140 | unsigned long abs_usecs; | |
1141 | unsigned long rel_usecs; | |
1142 | char *comm; | |
1143 | int S; | |
1144 | ||
1145 | if (!next_entry) | |
1146 | next_entry = entry; | |
1147 | rel_usecs = ns2usecs(next_entry->t - entry->t); | |
1148 | abs_usecs = ns2usecs(entry->t - iter->tr->time_start); | |
1149 | ||
1150 | if (verbose) { | |
1151 | comm = trace_find_cmdline(entry->pid); | |
214023c3 SR |
1152 | trace_seq_printf(s, "%16s %5d %d %d %08x %08x [%08lx]" |
1153 | " %ld.%03ldms (+%ld.%03ldms): ", | |
1154 | comm, | |
1155 | entry->pid, cpu, entry->flags, | |
1156 | entry->preempt_count, trace_idx, | |
1157 | ns2usecs(entry->t), | |
1158 | abs_usecs/1000, | |
1159 | abs_usecs % 1000, rel_usecs/1000, | |
1160 | rel_usecs % 1000); | |
bc0c38d1 | 1161 | } else { |
214023c3 SR |
1162 | lat_print_generic(s, entry, cpu); |
1163 | lat_print_timestamp(s, abs_usecs, rel_usecs); | |
bc0c38d1 SR |
1164 | } |
1165 | switch (entry->type) { | |
1166 | case TRACE_FN: | |
214023c3 SR |
1167 | seq_print_ip_sym(s, entry->fn.ip, sym_flags); |
1168 | trace_seq_puts(s, " ("); | |
1169 | seq_print_ip_sym(s, entry->fn.parent_ip, sym_flags); | |
1170 | trace_seq_puts(s, ")\n"); | |
bc0c38d1 SR |
1171 | break; |
1172 | case TRACE_CTX: | |
1173 | S = entry->ctx.prev_state < sizeof(state_to_char) ? | |
1174 | state_to_char[entry->ctx.prev_state] : 'X'; | |
1175 | comm = trace_find_cmdline(entry->ctx.next_pid); | |
214023c3 SR |
1176 | trace_seq_printf(s, " %d:%d:%c --> %d:%d %s\n", |
1177 | entry->ctx.prev_pid, | |
1178 | entry->ctx.prev_prio, | |
1179 | S, | |
1180 | entry->ctx.next_pid, | |
1181 | entry->ctx.next_prio, | |
1182 | comm); | |
bc0c38d1 | 1183 | break; |
f0a920d5 IM |
1184 | case TRACE_SPECIAL: |
1185 | trace_seq_printf(s, " %lx %lx %lx\n", | |
1186 | entry->special.arg1, | |
1187 | entry->special.arg2, | |
1188 | entry->special.arg3); | |
1189 | break; | |
89b2f978 | 1190 | default: |
214023c3 | 1191 | trace_seq_printf(s, "Unknown type %d\n", entry->type); |
bc0c38d1 | 1192 | } |
f9896bf3 | 1193 | return 1; |
bc0c38d1 SR |
1194 | } |
1195 | ||
f9896bf3 | 1196 | static notrace int print_trace_fmt(struct trace_iterator *iter) |
bc0c38d1 | 1197 | { |
214023c3 | 1198 | struct trace_seq *s = &iter->seq; |
bc0c38d1 | 1199 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); |
4e3c3333 | 1200 | struct trace_entry *entry; |
bc0c38d1 SR |
1201 | unsigned long usec_rem; |
1202 | unsigned long long t; | |
1203 | unsigned long secs; | |
1204 | char *comm; | |
1205 | int S; | |
b3806b43 | 1206 | int ret; |
bc0c38d1 | 1207 | |
4e3c3333 IM |
1208 | entry = iter->ent; |
1209 | ||
bc0c38d1 SR |
1210 | comm = trace_find_cmdline(iter->ent->pid); |
1211 | ||
cdd31cd2 | 1212 | t = ns2usecs(entry->t); |
bc0c38d1 SR |
1213 | usec_rem = do_div(t, 1000000ULL); |
1214 | secs = (unsigned long)t; | |
1215 | ||
b3806b43 SR |
1216 | ret = trace_seq_printf(s, "%16s-%-5d ", comm, entry->pid); |
1217 | if (!ret) | |
1218 | return 0; | |
1219 | ret = trace_seq_printf(s, "[%02d] ", iter->cpu); | |
1220 | if (!ret) | |
1221 | return 0; | |
1222 | ret = trace_seq_printf(s, "%5lu.%06lu: ", secs, usec_rem); | |
1223 | if (!ret) | |
1224 | return 0; | |
bc0c38d1 SR |
1225 | |
1226 | switch (entry->type) { | |
1227 | case TRACE_FN: | |
b3806b43 SR |
1228 | ret = seq_print_ip_sym(s, entry->fn.ip, sym_flags); |
1229 | if (!ret) | |
1230 | return 0; | |
bc0c38d1 SR |
1231 | if ((sym_flags & TRACE_ITER_PRINT_PARENT) && |
1232 | entry->fn.parent_ip) { | |
b3806b43 SR |
1233 | ret = trace_seq_printf(s, " <-"); |
1234 | if (!ret) | |
1235 | return 0; | |
1236 | ret = seq_print_ip_sym(s, entry->fn.parent_ip, | |
1237 | sym_flags); | |
1238 | if (!ret) | |
1239 | return 0; | |
bc0c38d1 | 1240 | } |
b3806b43 SR |
1241 | ret = trace_seq_printf(s, "\n"); |
1242 | if (!ret) | |
1243 | return 0; | |
bc0c38d1 SR |
1244 | break; |
1245 | case TRACE_CTX: | |
1246 | S = entry->ctx.prev_state < sizeof(state_to_char) ? | |
1247 | state_to_char[entry->ctx.prev_state] : 'X'; | |
b3806b43 SR |
1248 | ret = trace_seq_printf(s, " %d:%d:%c ==> %d:%d\n", |
1249 | entry->ctx.prev_pid, | |
1250 | entry->ctx.prev_prio, | |
1251 | S, | |
1252 | entry->ctx.next_pid, | |
1253 | entry->ctx.next_prio); | |
1254 | if (!ret) | |
1255 | return 0; | |
bc0c38d1 | 1256 | break; |
f0a920d5 IM |
1257 | case TRACE_SPECIAL: |
1258 | ret = trace_seq_printf(s, " %lx %lx %lx\n", | |
1259 | entry->special.arg1, | |
1260 | entry->special.arg2, | |
1261 | entry->special.arg3); | |
1262 | if (!ret) | |
1263 | return 0; | |
1264 | break; | |
bc0c38d1 | 1265 | } |
b3806b43 | 1266 | return 1; |
bc0c38d1 SR |
1267 | } |
1268 | ||
f9896bf3 IM |
1269 | static notrace int print_raw_fmt(struct trace_iterator *iter) |
1270 | { | |
1271 | struct trace_seq *s = &iter->seq; | |
1272 | struct trace_entry *entry; | |
1273 | int ret; | |
1274 | int S; | |
1275 | ||
1276 | entry = iter->ent; | |
1277 | ||
1278 | ret = trace_seq_printf(s, "%d %d %llu ", | |
1279 | entry->pid, iter->cpu, entry->t); | |
1280 | if (!ret) | |
1281 | return 0; | |
1282 | ||
1283 | switch (entry->type) { | |
1284 | case TRACE_FN: | |
1285 | ret = trace_seq_printf(s, "%x %x\n", | |
1286 | entry->fn.ip, entry->fn.parent_ip); | |
1287 | if (!ret) | |
1288 | return 0; | |
1289 | break; | |
1290 | case TRACE_CTX: | |
1291 | S = entry->ctx.prev_state < sizeof(state_to_char) ? | |
1292 | state_to_char[entry->ctx.prev_state] : 'X'; | |
1293 | ret = trace_seq_printf(s, "%d %d %c %d %d\n", | |
1294 | entry->ctx.prev_pid, | |
1295 | entry->ctx.prev_prio, | |
1296 | S, | |
1297 | entry->ctx.next_pid, | |
1298 | entry->ctx.next_prio); | |
1299 | if (!ret) | |
1300 | return 0; | |
1301 | break; | |
f0a920d5 IM |
1302 | case TRACE_SPECIAL: |
1303 | ret = trace_seq_printf(s, " %lx %lx %lx\n", | |
1304 | entry->special.arg1, | |
1305 | entry->special.arg2, | |
1306 | entry->special.arg3); | |
1307 | if (!ret) | |
1308 | return 0; | |
1309 | break; | |
f9896bf3 IM |
1310 | } |
1311 | return 1; | |
1312 | } | |
1313 | ||
cb0f12aa IM |
1314 | #define SEQ_PUT_FIELD_RET(s, x) \ |
1315 | do { \ | |
1316 | if (!trace_seq_putmem(s, &(x), sizeof(x))) \ | |
1317 | return 0; \ | |
1318 | } while (0) | |
1319 | ||
5e3ca0ec IM |
1320 | #define SEQ_PUT_HEX_FIELD_RET(s, x) \ |
1321 | do { \ | |
1322 | if (!trace_seq_putmem_hex(s, &(x), sizeof(x))) \ | |
1323 | return 0; \ | |
1324 | } while (0) | |
1325 | ||
1326 | static notrace int print_hex_fmt(struct trace_iterator *iter) | |
1327 | { | |
1328 | struct trace_seq *s = &iter->seq; | |
1329 | unsigned char newline = '\n'; | |
1330 | struct trace_entry *entry; | |
1331 | int S; | |
1332 | ||
1333 | entry = iter->ent; | |
1334 | ||
1335 | SEQ_PUT_HEX_FIELD_RET(s, entry->pid); | |
1336 | SEQ_PUT_HEX_FIELD_RET(s, iter->cpu); | |
1337 | SEQ_PUT_HEX_FIELD_RET(s, entry->t); | |
1338 | ||
1339 | switch (entry->type) { | |
1340 | case TRACE_FN: | |
1341 | SEQ_PUT_HEX_FIELD_RET(s, entry->fn.ip); | |
1342 | SEQ_PUT_HEX_FIELD_RET(s, entry->fn.parent_ip); | |
1343 | break; | |
1344 | case TRACE_CTX: | |
1345 | S = entry->ctx.prev_state < sizeof(state_to_char) ? | |
1346 | state_to_char[entry->ctx.prev_state] : 'X'; | |
1347 | SEQ_PUT_HEX_FIELD_RET(s, entry->ctx.prev_pid); | |
1348 | SEQ_PUT_HEX_FIELD_RET(s, entry->ctx.prev_prio); | |
1349 | SEQ_PUT_HEX_FIELD_RET(s, S); | |
1350 | SEQ_PUT_HEX_FIELD_RET(s, entry->ctx.next_pid); | |
1351 | SEQ_PUT_HEX_FIELD_RET(s, entry->ctx.next_prio); | |
1352 | SEQ_PUT_HEX_FIELD_RET(s, entry->fn.parent_ip); | |
1353 | break; | |
1354 | case TRACE_SPECIAL: | |
1355 | SEQ_PUT_HEX_FIELD_RET(s, entry->special.arg1); | |
1356 | SEQ_PUT_HEX_FIELD_RET(s, entry->special.arg2); | |
1357 | SEQ_PUT_HEX_FIELD_RET(s, entry->special.arg3); | |
1358 | break; | |
1359 | } | |
1360 | SEQ_PUT_FIELD_RET(s, newline); | |
1361 | ||
1362 | return 1; | |
1363 | } | |
1364 | ||
cb0f12aa IM |
1365 | static notrace int print_bin_fmt(struct trace_iterator *iter) |
1366 | { | |
1367 | struct trace_seq *s = &iter->seq; | |
1368 | struct trace_entry *entry; | |
1369 | ||
1370 | entry = iter->ent; | |
1371 | ||
1372 | SEQ_PUT_FIELD_RET(s, entry->pid); | |
1373 | SEQ_PUT_FIELD_RET(s, entry->cpu); | |
1374 | SEQ_PUT_FIELD_RET(s, entry->t); | |
1375 | ||
1376 | switch (entry->type) { | |
1377 | case TRACE_FN: | |
1378 | SEQ_PUT_FIELD_RET(s, entry->fn.ip); | |
1379 | SEQ_PUT_FIELD_RET(s, entry->fn.parent_ip); | |
1380 | break; | |
1381 | case TRACE_CTX: | |
1382 | SEQ_PUT_FIELD_RET(s, entry->ctx.prev_pid); | |
1383 | SEQ_PUT_FIELD_RET(s, entry->ctx.prev_prio); | |
1384 | SEQ_PUT_FIELD_RET(s, entry->ctx.prev_state); | |
1385 | SEQ_PUT_FIELD_RET(s, entry->ctx.next_pid); | |
1386 | SEQ_PUT_FIELD_RET(s, entry->ctx.next_prio); | |
1387 | break; | |
f0a920d5 IM |
1388 | case TRACE_SPECIAL: |
1389 | SEQ_PUT_FIELD_RET(s, entry->special.arg1); | |
1390 | SEQ_PUT_FIELD_RET(s, entry->special.arg2); | |
1391 | SEQ_PUT_FIELD_RET(s, entry->special.arg3); | |
1392 | break; | |
cb0f12aa IM |
1393 | } |
1394 | return 1; | |
1395 | } | |
1396 | ||
bc0c38d1 SR |
1397 | static int trace_empty(struct trace_iterator *iter) |
1398 | { | |
1399 | struct trace_array_cpu *data; | |
1400 | int cpu; | |
1401 | ||
1402 | for_each_possible_cpu(cpu) { | |
1403 | data = iter->tr->data[cpu]; | |
1404 | ||
b3806b43 SR |
1405 | if (head_page(data) && data->trace_idx && |
1406 | (data->trace_tail != data->trace_head || | |
1407 | data->trace_tail_idx != data->trace_head_idx)) | |
bc0c38d1 SR |
1408 | return 0; |
1409 | } | |
1410 | return 1; | |
1411 | } | |
1412 | ||
f9896bf3 IM |
1413 | static int print_trace_line(struct trace_iterator *iter) |
1414 | { | |
cb0f12aa IM |
1415 | if (trace_flags & TRACE_ITER_BIN) |
1416 | return print_bin_fmt(iter); | |
1417 | ||
5e3ca0ec IM |
1418 | if (trace_flags & TRACE_ITER_HEX) |
1419 | return print_hex_fmt(iter); | |
1420 | ||
f9896bf3 IM |
1421 | if (trace_flags & TRACE_ITER_RAW) |
1422 | return print_raw_fmt(iter); | |
1423 | ||
1424 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) | |
1425 | return print_lat_fmt(iter, iter->idx, iter->cpu); | |
1426 | ||
1427 | return print_trace_fmt(iter); | |
1428 | } | |
1429 | ||
bc0c38d1 SR |
1430 | static int s_show(struct seq_file *m, void *v) |
1431 | { | |
1432 | struct trace_iterator *iter = v; | |
1433 | ||
1434 | if (iter->ent == NULL) { | |
1435 | if (iter->tr) { | |
1436 | seq_printf(m, "# tracer: %s\n", iter->trace->name); | |
1437 | seq_puts(m, "#\n"); | |
1438 | } | |
1439 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) { | |
1440 | /* print nothing if the buffers are empty */ | |
1441 | if (trace_empty(iter)) | |
1442 | return 0; | |
1443 | print_trace_header(m, iter); | |
1444 | if (!(trace_flags & TRACE_ITER_VERBOSE)) | |
1445 | print_lat_help_header(m); | |
1446 | } else { | |
1447 | if (!(trace_flags & TRACE_ITER_VERBOSE)) | |
1448 | print_func_help_header(m); | |
1449 | } | |
1450 | } else { | |
f9896bf3 | 1451 | print_trace_line(iter); |
214023c3 | 1452 | trace_print_seq(m, &iter->seq); |
bc0c38d1 SR |
1453 | } |
1454 | ||
1455 | return 0; | |
1456 | } | |
1457 | ||
1458 | static struct seq_operations tracer_seq_ops = { | |
4bf39a94 IM |
1459 | .start = s_start, |
1460 | .next = s_next, | |
1461 | .stop = s_stop, | |
1462 | .show = s_show, | |
bc0c38d1 SR |
1463 | }; |
1464 | ||
1465 | static struct trace_iterator notrace * | |
1466 | __tracing_open(struct inode *inode, struct file *file, int *ret) | |
1467 | { | |
1468 | struct trace_iterator *iter; | |
1469 | ||
60a11774 SR |
1470 | if (tracing_disabled) { |
1471 | *ret = -ENODEV; | |
1472 | return NULL; | |
1473 | } | |
1474 | ||
bc0c38d1 SR |
1475 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); |
1476 | if (!iter) { | |
1477 | *ret = -ENOMEM; | |
1478 | goto out; | |
1479 | } | |
1480 | ||
1481 | mutex_lock(&trace_types_lock); | |
1482 | if (current_trace && current_trace->print_max) | |
1483 | iter->tr = &max_tr; | |
1484 | else | |
1485 | iter->tr = inode->i_private; | |
1486 | iter->trace = current_trace; | |
1487 | iter->pos = -1; | |
1488 | ||
1489 | /* TODO stop tracer */ | |
1490 | *ret = seq_open(file, &tracer_seq_ops); | |
1491 | if (!*ret) { | |
1492 | struct seq_file *m = file->private_data; | |
1493 | m->private = iter; | |
1494 | ||
1495 | /* stop the trace while dumping */ | |
1496 | if (iter->tr->ctrl) | |
1497 | tracer_enabled = 0; | |
1498 | ||
1499 | if (iter->trace && iter->trace->open) | |
1500 | iter->trace->open(iter); | |
1501 | } else { | |
1502 | kfree(iter); | |
1503 | iter = NULL; | |
1504 | } | |
1505 | mutex_unlock(&trace_types_lock); | |
1506 | ||
1507 | out: | |
1508 | return iter; | |
1509 | } | |
1510 | ||
1511 | int tracing_open_generic(struct inode *inode, struct file *filp) | |
1512 | { | |
60a11774 SR |
1513 | if (tracing_disabled) |
1514 | return -ENODEV; | |
1515 | ||
bc0c38d1 SR |
1516 | filp->private_data = inode->i_private; |
1517 | return 0; | |
1518 | } | |
1519 | ||
1520 | int tracing_release(struct inode *inode, struct file *file) | |
1521 | { | |
1522 | struct seq_file *m = (struct seq_file *)file->private_data; | |
1523 | struct trace_iterator *iter = m->private; | |
1524 | ||
1525 | mutex_lock(&trace_types_lock); | |
1526 | if (iter->trace && iter->trace->close) | |
1527 | iter->trace->close(iter); | |
1528 | ||
1529 | /* reenable tracing if it was previously enabled */ | |
1530 | if (iter->tr->ctrl) | |
1531 | tracer_enabled = 1; | |
1532 | mutex_unlock(&trace_types_lock); | |
1533 | ||
1534 | seq_release(inode, file); | |
1535 | kfree(iter); | |
1536 | return 0; | |
1537 | } | |
1538 | ||
1539 | static int tracing_open(struct inode *inode, struct file *file) | |
1540 | { | |
1541 | int ret; | |
1542 | ||
1543 | __tracing_open(inode, file, &ret); | |
1544 | ||
1545 | return ret; | |
1546 | } | |
1547 | ||
1548 | static int tracing_lt_open(struct inode *inode, struct file *file) | |
1549 | { | |
1550 | struct trace_iterator *iter; | |
1551 | int ret; | |
1552 | ||
1553 | iter = __tracing_open(inode, file, &ret); | |
1554 | ||
1555 | if (!ret) | |
1556 | iter->iter_flags |= TRACE_FILE_LAT_FMT; | |
1557 | ||
1558 | return ret; | |
1559 | } | |
1560 | ||
1561 | ||
4e3c3333 | 1562 | static notrace void * |
bc0c38d1 SR |
1563 | t_next(struct seq_file *m, void *v, loff_t *pos) |
1564 | { | |
1565 | struct tracer *t = m->private; | |
1566 | ||
1567 | (*pos)++; | |
1568 | ||
1569 | if (t) | |
1570 | t = t->next; | |
1571 | ||
1572 | m->private = t; | |
1573 | ||
1574 | return t; | |
1575 | } | |
1576 | ||
1577 | static void *t_start(struct seq_file *m, loff_t *pos) | |
1578 | { | |
1579 | struct tracer *t = m->private; | |
1580 | loff_t l = 0; | |
1581 | ||
1582 | mutex_lock(&trace_types_lock); | |
1583 | for (; t && l < *pos; t = t_next(m, t, &l)) | |
1584 | ; | |
1585 | ||
1586 | return t; | |
1587 | } | |
1588 | ||
1589 | static void t_stop(struct seq_file *m, void *p) | |
1590 | { | |
1591 | mutex_unlock(&trace_types_lock); | |
1592 | } | |
1593 | ||
1594 | static int t_show(struct seq_file *m, void *v) | |
1595 | { | |
1596 | struct tracer *t = v; | |
1597 | ||
1598 | if (!t) | |
1599 | return 0; | |
1600 | ||
1601 | seq_printf(m, "%s", t->name); | |
1602 | if (t->next) | |
1603 | seq_putc(m, ' '); | |
1604 | else | |
1605 | seq_putc(m, '\n'); | |
1606 | ||
1607 | return 0; | |
1608 | } | |
1609 | ||
1610 | static struct seq_operations show_traces_seq_ops = { | |
4bf39a94 IM |
1611 | .start = t_start, |
1612 | .next = t_next, | |
1613 | .stop = t_stop, | |
1614 | .show = t_show, | |
bc0c38d1 SR |
1615 | }; |
1616 | ||
1617 | static int show_traces_open(struct inode *inode, struct file *file) | |
1618 | { | |
1619 | int ret; | |
1620 | ||
60a11774 SR |
1621 | if (tracing_disabled) |
1622 | return -ENODEV; | |
1623 | ||
bc0c38d1 SR |
1624 | ret = seq_open(file, &show_traces_seq_ops); |
1625 | if (!ret) { | |
1626 | struct seq_file *m = file->private_data; | |
1627 | m->private = trace_types; | |
1628 | } | |
1629 | ||
1630 | return ret; | |
1631 | } | |
1632 | ||
1633 | static struct file_operations tracing_fops = { | |
4bf39a94 IM |
1634 | .open = tracing_open, |
1635 | .read = seq_read, | |
1636 | .llseek = seq_lseek, | |
1637 | .release = tracing_release, | |
bc0c38d1 SR |
1638 | }; |
1639 | ||
1640 | static struct file_operations tracing_lt_fops = { | |
4bf39a94 IM |
1641 | .open = tracing_lt_open, |
1642 | .read = seq_read, | |
1643 | .llseek = seq_lseek, | |
1644 | .release = tracing_release, | |
bc0c38d1 SR |
1645 | }; |
1646 | ||
1647 | static struct file_operations show_traces_fops = { | |
1648 | .open = show_traces_open, | |
1649 | .read = seq_read, | |
1650 | .release = seq_release, | |
1651 | }; | |
1652 | ||
1653 | static ssize_t | |
1654 | tracing_iter_ctrl_read(struct file *filp, char __user *ubuf, | |
1655 | size_t cnt, loff_t *ppos) | |
1656 | { | |
1657 | char *buf; | |
1658 | int r = 0; | |
1659 | int len = 0; | |
1660 | int i; | |
1661 | ||
1662 | /* calulate max size */ | |
1663 | for (i = 0; trace_options[i]; i++) { | |
1664 | len += strlen(trace_options[i]); | |
1665 | len += 3; /* "no" and space */ | |
1666 | } | |
1667 | ||
1668 | /* +2 for \n and \0 */ | |
1669 | buf = kmalloc(len + 2, GFP_KERNEL); | |
1670 | if (!buf) | |
1671 | return -ENOMEM; | |
1672 | ||
1673 | for (i = 0; trace_options[i]; i++) { | |
1674 | if (trace_flags & (1 << i)) | |
1675 | r += sprintf(buf + r, "%s ", trace_options[i]); | |
1676 | else | |
1677 | r += sprintf(buf + r, "no%s ", trace_options[i]); | |
1678 | } | |
1679 | ||
1680 | r += sprintf(buf + r, "\n"); | |
1681 | WARN_ON(r >= len + 2); | |
1682 | ||
1683 | r = simple_read_from_buffer(ubuf, cnt, ppos, | |
1684 | buf, r); | |
1685 | ||
1686 | kfree(buf); | |
1687 | ||
1688 | return r; | |
1689 | } | |
1690 | ||
1691 | static ssize_t | |
1692 | tracing_iter_ctrl_write(struct file *filp, const char __user *ubuf, | |
1693 | size_t cnt, loff_t *ppos) | |
1694 | { | |
1695 | char buf[64]; | |
1696 | char *cmp = buf; | |
1697 | int neg = 0; | |
1698 | int i; | |
1699 | ||
1700 | if (cnt > 63) | |
1701 | cnt = 63; | |
1702 | ||
1703 | if (copy_from_user(&buf, ubuf, cnt)) | |
1704 | return -EFAULT; | |
1705 | ||
1706 | buf[cnt] = 0; | |
1707 | ||
1708 | if (strncmp(buf, "no", 2) == 0) { | |
1709 | neg = 1; | |
1710 | cmp += 2; | |
1711 | } | |
1712 | ||
1713 | for (i = 0; trace_options[i]; i++) { | |
1714 | int len = strlen(trace_options[i]); | |
1715 | ||
1716 | if (strncmp(cmp, trace_options[i], len) == 0) { | |
1717 | if (neg) | |
1718 | trace_flags &= ~(1 << i); | |
1719 | else | |
1720 | trace_flags |= (1 << i); | |
1721 | break; | |
1722 | } | |
1723 | } | |
1724 | ||
1725 | filp->f_pos += cnt; | |
1726 | ||
1727 | return cnt; | |
1728 | } | |
1729 | ||
1730 | static struct file_operations tracing_iter_fops = { | |
1731 | .open = tracing_open_generic, | |
1732 | .read = tracing_iter_ctrl_read, | |
1733 | .write = tracing_iter_ctrl_write, | |
1734 | }; | |
1735 | ||
7bd2f24c IM |
1736 | static const char readme_msg[] = |
1737 | "tracing mini-HOWTO:\n\n" | |
1738 | "# mkdir /debug\n" | |
1739 | "# mount -t debugfs nodev /debug\n\n" | |
1740 | "# cat /debug/tracing/available_tracers\n" | |
1741 | "wakeup preemptirqsoff preemptoff irqsoff ftrace sched_switch none\n\n" | |
1742 | "# cat /debug/tracing/current_tracer\n" | |
1743 | "none\n" | |
1744 | "# echo sched_switch > /debug/tracing/current_tracer\n" | |
1745 | "# cat /debug/tracing/current_tracer\n" | |
1746 | "sched_switch\n" | |
1747 | "# cat /debug/tracing/iter_ctrl\n" | |
1748 | "noprint-parent nosym-offset nosym-addr noverbose\n" | |
1749 | "# echo print-parent > /debug/tracing/iter_ctrl\n" | |
1750 | "# echo 1 > /debug/tracing/tracing_enabled\n" | |
1751 | "# cat /debug/tracing/trace > /tmp/trace.txt\n" | |
1752 | "echo 0 > /debug/tracing/tracing_enabled\n" | |
1753 | ; | |
1754 | ||
1755 | static ssize_t | |
1756 | tracing_readme_read(struct file *filp, char __user *ubuf, | |
1757 | size_t cnt, loff_t *ppos) | |
1758 | { | |
1759 | return simple_read_from_buffer(ubuf, cnt, ppos, | |
1760 | readme_msg, strlen(readme_msg)); | |
1761 | } | |
1762 | ||
1763 | static struct file_operations tracing_readme_fops = { | |
1764 | .open = tracing_open_generic, | |
1765 | .read = tracing_readme_read, | |
1766 | }; | |
1767 | ||
1768 | ||
bc0c38d1 SR |
1769 | static ssize_t |
1770 | tracing_ctrl_read(struct file *filp, char __user *ubuf, | |
1771 | size_t cnt, loff_t *ppos) | |
1772 | { | |
1773 | struct trace_array *tr = filp->private_data; | |
1774 | char buf[64]; | |
1775 | int r; | |
1776 | ||
1777 | r = sprintf(buf, "%ld\n", tr->ctrl); | |
4e3c3333 | 1778 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
1779 | } |
1780 | ||
1781 | static ssize_t | |
1782 | tracing_ctrl_write(struct file *filp, const char __user *ubuf, | |
1783 | size_t cnt, loff_t *ppos) | |
1784 | { | |
1785 | struct trace_array *tr = filp->private_data; | |
1786 | long val; | |
1787 | char buf[64]; | |
1788 | ||
1789 | if (cnt > 63) | |
1790 | cnt = 63; | |
1791 | ||
1792 | if (copy_from_user(&buf, ubuf, cnt)) | |
1793 | return -EFAULT; | |
1794 | ||
1795 | buf[cnt] = 0; | |
1796 | ||
1797 | val = simple_strtoul(buf, NULL, 10); | |
1798 | ||
1799 | val = !!val; | |
1800 | ||
1801 | mutex_lock(&trace_types_lock); | |
1802 | if (tr->ctrl ^ val) { | |
1803 | if (val) | |
1804 | tracer_enabled = 1; | |
1805 | else | |
1806 | tracer_enabled = 0; | |
1807 | ||
1808 | tr->ctrl = val; | |
1809 | ||
1810 | if (current_trace && current_trace->ctrl_update) | |
1811 | current_trace->ctrl_update(tr); | |
1812 | } | |
1813 | mutex_unlock(&trace_types_lock); | |
1814 | ||
1815 | filp->f_pos += cnt; | |
1816 | ||
1817 | return cnt; | |
1818 | } | |
1819 | ||
1820 | static ssize_t | |
1821 | tracing_set_trace_read(struct file *filp, char __user *ubuf, | |
1822 | size_t cnt, loff_t *ppos) | |
1823 | { | |
1824 | char buf[max_tracer_type_len+2]; | |
1825 | int r; | |
1826 | ||
1827 | mutex_lock(&trace_types_lock); | |
1828 | if (current_trace) | |
1829 | r = sprintf(buf, "%s\n", current_trace->name); | |
1830 | else | |
1831 | r = sprintf(buf, "\n"); | |
1832 | mutex_unlock(&trace_types_lock); | |
1833 | ||
4bf39a94 | 1834 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
1835 | } |
1836 | ||
1837 | static ssize_t | |
1838 | tracing_set_trace_write(struct file *filp, const char __user *ubuf, | |
1839 | size_t cnt, loff_t *ppos) | |
1840 | { | |
1841 | struct trace_array *tr = &global_trace; | |
1842 | struct tracer *t; | |
1843 | char buf[max_tracer_type_len+1]; | |
1844 | int i; | |
1845 | ||
1846 | if (cnt > max_tracer_type_len) | |
1847 | cnt = max_tracer_type_len; | |
1848 | ||
1849 | if (copy_from_user(&buf, ubuf, cnt)) | |
1850 | return -EFAULT; | |
1851 | ||
1852 | buf[cnt] = 0; | |
1853 | ||
1854 | /* strip ending whitespace. */ | |
1855 | for (i = cnt - 1; i > 0 && isspace(buf[i]); i--) | |
1856 | buf[i] = 0; | |
1857 | ||
1858 | mutex_lock(&trace_types_lock); | |
1859 | for (t = trace_types; t; t = t->next) { | |
1860 | if (strcmp(t->name, buf) == 0) | |
1861 | break; | |
1862 | } | |
1863 | if (!t || t == current_trace) | |
1864 | goto out; | |
1865 | ||
1866 | if (current_trace && current_trace->reset) | |
1867 | current_trace->reset(tr); | |
1868 | ||
1869 | current_trace = t; | |
1870 | if (t->init) | |
1871 | t->init(tr); | |
1872 | ||
1873 | out: | |
1874 | mutex_unlock(&trace_types_lock); | |
1875 | ||
1876 | filp->f_pos += cnt; | |
1877 | ||
1878 | return cnt; | |
1879 | } | |
1880 | ||
1881 | static ssize_t | |
1882 | tracing_max_lat_read(struct file *filp, char __user *ubuf, | |
1883 | size_t cnt, loff_t *ppos) | |
1884 | { | |
1885 | unsigned long *ptr = filp->private_data; | |
1886 | char buf[64]; | |
1887 | int r; | |
1888 | ||
1889 | r = snprintf(buf, 64, "%ld\n", | |
1890 | *ptr == (unsigned long)-1 ? -1 : nsecs_to_usecs(*ptr)); | |
1891 | if (r > 64) | |
1892 | r = 64; | |
4bf39a94 | 1893 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
1894 | } |
1895 | ||
1896 | static ssize_t | |
1897 | tracing_max_lat_write(struct file *filp, const char __user *ubuf, | |
1898 | size_t cnt, loff_t *ppos) | |
1899 | { | |
1900 | long *ptr = filp->private_data; | |
1901 | long val; | |
1902 | char buf[64]; | |
1903 | ||
1904 | if (cnt > 63) | |
1905 | cnt = 63; | |
1906 | ||
1907 | if (copy_from_user(&buf, ubuf, cnt)) | |
1908 | return -EFAULT; | |
1909 | ||
1910 | buf[cnt] = 0; | |
1911 | ||
1912 | val = simple_strtoul(buf, NULL, 10); | |
1913 | ||
1914 | *ptr = val * 1000; | |
1915 | ||
1916 | return cnt; | |
1917 | } | |
1918 | ||
b3806b43 SR |
1919 | static atomic_t tracing_reader; |
1920 | ||
1921 | static int tracing_open_pipe(struct inode *inode, struct file *filp) | |
1922 | { | |
1923 | struct trace_iterator *iter; | |
1924 | ||
1925 | if (tracing_disabled) | |
1926 | return -ENODEV; | |
1927 | ||
1928 | /* We only allow for reader of the pipe */ | |
1929 | if (atomic_inc_return(&tracing_reader) != 1) { | |
1930 | atomic_dec(&tracing_reader); | |
1931 | return -EBUSY; | |
1932 | } | |
1933 | ||
1934 | /* create a buffer to store the information to pass to userspace */ | |
1935 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); | |
1936 | if (!iter) | |
1937 | return -ENOMEM; | |
1938 | ||
1939 | iter->tr = &global_trace; | |
1940 | ||
1941 | filp->private_data = iter; | |
1942 | ||
1943 | return 0; | |
1944 | } | |
1945 | ||
1946 | static int tracing_release_pipe(struct inode *inode, struct file *file) | |
1947 | { | |
1948 | struct trace_iterator *iter = file->private_data; | |
1949 | ||
1950 | kfree(iter); | |
1951 | atomic_dec(&tracing_reader); | |
1952 | ||
1953 | return 0; | |
1954 | } | |
1955 | ||
1956 | /* | |
1957 | * Consumer reader. | |
1958 | */ | |
1959 | static ssize_t | |
1960 | tracing_read_pipe(struct file *filp, char __user *ubuf, | |
1961 | size_t cnt, loff_t *ppos) | |
1962 | { | |
1963 | struct trace_iterator *iter = filp->private_data; | |
1964 | struct trace_array_cpu *data; | |
1965 | static cpumask_t mask; | |
b3806b43 SR |
1966 | static int start; |
1967 | unsigned long flags; | |
25770467 | 1968 | #ifdef CONFIG_FTRACE |
2e0f5761 | 1969 | int ftrace_save; |
25770467 | 1970 | #endif |
b3806b43 SR |
1971 | int read = 0; |
1972 | int cpu; | |
1973 | int len; | |
1974 | int ret; | |
1975 | ||
1976 | /* return any leftover data */ | |
1977 | if (iter->seq.len > start) { | |
1978 | len = iter->seq.len - start; | |
1979 | if (cnt > len) | |
1980 | cnt = len; | |
1981 | ret = copy_to_user(ubuf, iter->seq.buffer + start, cnt); | |
1982 | if (ret) | |
1983 | cnt = -EFAULT; | |
1984 | ||
1985 | start += len; | |
1986 | ||
1987 | return cnt; | |
1988 | } | |
1989 | ||
1990 | trace_seq_reset(&iter->seq); | |
1991 | start = 0; | |
1992 | ||
1993 | while (trace_empty(iter)) { | |
1994 | /* | |
1995 | * This is a make-shift waitqueue. The reason we don't use | |
1996 | * an actual wait queue is because: | |
1997 | * 1) we only ever have one waiter | |
1998 | * 2) the tracing, traces all functions, we don't want | |
1999 | * the overhead of calling wake_up and friends | |
2000 | * (and tracing them too) | |
2001 | * Anyway, this is really very primitive wakeup. | |
2002 | */ | |
2003 | set_current_state(TASK_INTERRUPTIBLE); | |
2004 | iter->tr->waiter = current; | |
2005 | ||
2006 | /* sleep for one second, and try again. */ | |
2007 | schedule_timeout(HZ); | |
2008 | ||
2009 | iter->tr->waiter = NULL; | |
2010 | ||
2011 | if (signal_pending(current)) | |
2012 | return -EINTR; | |
2013 | ||
2014 | /* | |
2015 | * We block until we read something and tracing is disabled. | |
2016 | * We still block if tracing is disabled, but we have never | |
2017 | * read anything. This allows a user to cat this file, and | |
2018 | * then enable tracing. But after we have read something, | |
2019 | * we give an EOF when tracing is again disabled. | |
2020 | * | |
2021 | * iter->pos will be 0 if we haven't read anything. | |
2022 | */ | |
2023 | if (!tracer_enabled && iter->pos) | |
2024 | break; | |
2025 | ||
2026 | continue; | |
2027 | } | |
2028 | ||
2029 | /* stop when tracing is finished */ | |
2030 | if (trace_empty(iter)) | |
2031 | return 0; | |
2032 | ||
2033 | if (cnt >= PAGE_SIZE) | |
2034 | cnt = PAGE_SIZE - 1; | |
2035 | ||
2036 | memset(iter, 0, sizeof(*iter)); | |
2037 | iter->tr = &global_trace; | |
2038 | iter->pos = -1; | |
2039 | ||
2040 | /* | |
2041 | * We need to stop all tracing on all CPUS to read the | |
2042 | * the next buffer. This is a bit expensive, but is | |
2043 | * not done often. We fill all what we can read, | |
2044 | * and then release the locks again. | |
2045 | */ | |
2046 | ||
2047 | cpus_clear(mask); | |
2048 | local_irq_save(flags); | |
25770467 | 2049 | #ifdef CONFIG_FTRACE |
2e0f5761 IM |
2050 | ftrace_save = ftrace_enabled; |
2051 | ftrace_enabled = 0; | |
25770467 | 2052 | #endif |
2e0f5761 | 2053 | smp_wmb(); |
b3806b43 SR |
2054 | for_each_possible_cpu(cpu) { |
2055 | data = iter->tr->data[cpu]; | |
2056 | ||
2057 | if (!head_page(data) || !data->trace_idx) | |
2058 | continue; | |
2059 | ||
2060 | atomic_inc(&data->disabled); | |
b3806b43 SR |
2061 | cpu_set(cpu, mask); |
2062 | } | |
2063 | ||
2e0f5761 IM |
2064 | for_each_cpu_mask(cpu, mask) { |
2065 | data = iter->tr->data[cpu]; | |
2066 | spin_lock(&data->lock); | |
2067 | } | |
2068 | ||
088b1e42 SR |
2069 | while (find_next_entry_inc(iter) != NULL) { |
2070 | int len = iter->seq.len; | |
2071 | ||
f9896bf3 | 2072 | ret = print_trace_line(iter); |
088b1e42 SR |
2073 | if (!ret) { |
2074 | /* don't print partial lines */ | |
2075 | iter->seq.len = len; | |
b3806b43 | 2076 | break; |
088b1e42 | 2077 | } |
b3806b43 SR |
2078 | |
2079 | trace_consume(iter); | |
2080 | ||
2081 | if (iter->seq.len >= cnt) | |
2082 | break; | |
b3806b43 SR |
2083 | } |
2084 | ||
d4c5a2f5 | 2085 | for_each_cpu_mask(cpu, mask) { |
b3806b43 | 2086 | data = iter->tr->data[cpu]; |
b3806b43 | 2087 | spin_unlock(&data->lock); |
2e0f5761 IM |
2088 | } |
2089 | ||
2090 | for_each_cpu_mask(cpu, mask) { | |
2091 | data = iter->tr->data[cpu]; | |
b3806b43 SR |
2092 | atomic_dec(&data->disabled); |
2093 | } | |
25770467 | 2094 | #ifdef CONFIG_FTRACE |
2e0f5761 | 2095 | ftrace_enabled = ftrace_save; |
25770467 | 2096 | #endif |
b3806b43 SR |
2097 | local_irq_restore(flags); |
2098 | ||
2099 | /* Now copy what we have to the user */ | |
2100 | read = iter->seq.len; | |
2101 | if (read > cnt) | |
2102 | read = cnt; | |
2103 | ||
2104 | ret = copy_to_user(ubuf, iter->seq.buffer, read); | |
2105 | ||
2106 | if (read < iter->seq.len) | |
2107 | start = read; | |
2108 | else | |
2109 | trace_seq_reset(&iter->seq); | |
2110 | ||
2111 | if (ret) | |
2112 | read = -EFAULT; | |
2113 | ||
2114 | return read; | |
2115 | } | |
2116 | ||
bc0c38d1 | 2117 | static struct file_operations tracing_max_lat_fops = { |
4bf39a94 IM |
2118 | .open = tracing_open_generic, |
2119 | .read = tracing_max_lat_read, | |
2120 | .write = tracing_max_lat_write, | |
bc0c38d1 SR |
2121 | }; |
2122 | ||
2123 | static struct file_operations tracing_ctrl_fops = { | |
4bf39a94 IM |
2124 | .open = tracing_open_generic, |
2125 | .read = tracing_ctrl_read, | |
2126 | .write = tracing_ctrl_write, | |
bc0c38d1 SR |
2127 | }; |
2128 | ||
2129 | static struct file_operations set_tracer_fops = { | |
4bf39a94 IM |
2130 | .open = tracing_open_generic, |
2131 | .read = tracing_set_trace_read, | |
2132 | .write = tracing_set_trace_write, | |
bc0c38d1 SR |
2133 | }; |
2134 | ||
b3806b43 | 2135 | static struct file_operations tracing_pipe_fops = { |
4bf39a94 IM |
2136 | .open = tracing_open_pipe, |
2137 | .read = tracing_read_pipe, | |
2138 | .release = tracing_release_pipe, | |
b3806b43 SR |
2139 | }; |
2140 | ||
bc0c38d1 SR |
2141 | #ifdef CONFIG_DYNAMIC_FTRACE |
2142 | ||
2143 | static ssize_t | |
2144 | tracing_read_long(struct file *filp, char __user *ubuf, | |
2145 | size_t cnt, loff_t *ppos) | |
2146 | { | |
2147 | unsigned long *p = filp->private_data; | |
2148 | char buf[64]; | |
2149 | int r; | |
2150 | ||
2151 | r = sprintf(buf, "%ld\n", *p); | |
4bf39a94 IM |
2152 | |
2153 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
bc0c38d1 SR |
2154 | } |
2155 | ||
2156 | static struct file_operations tracing_read_long_fops = { | |
4bf39a94 IM |
2157 | .open = tracing_open_generic, |
2158 | .read = tracing_read_long, | |
bc0c38d1 SR |
2159 | }; |
2160 | #endif | |
2161 | ||
2162 | static struct dentry *d_tracer; | |
2163 | ||
2164 | struct dentry *tracing_init_dentry(void) | |
2165 | { | |
2166 | static int once; | |
2167 | ||
2168 | if (d_tracer) | |
2169 | return d_tracer; | |
2170 | ||
2171 | d_tracer = debugfs_create_dir("tracing", NULL); | |
2172 | ||
2173 | if (!d_tracer && !once) { | |
2174 | once = 1; | |
2175 | pr_warning("Could not create debugfs directory 'tracing'\n"); | |
2176 | return NULL; | |
2177 | } | |
2178 | ||
2179 | return d_tracer; | |
2180 | } | |
2181 | ||
60a11774 SR |
2182 | #ifdef CONFIG_FTRACE_SELFTEST |
2183 | /* Let selftest have access to static functions in this file */ | |
2184 | #include "trace_selftest.c" | |
2185 | #endif | |
2186 | ||
bc0c38d1 SR |
2187 | static __init void tracer_init_debugfs(void) |
2188 | { | |
2189 | struct dentry *d_tracer; | |
2190 | struct dentry *entry; | |
2191 | ||
2192 | d_tracer = tracing_init_dentry(); | |
2193 | ||
2194 | entry = debugfs_create_file("tracing_enabled", 0644, d_tracer, | |
2195 | &global_trace, &tracing_ctrl_fops); | |
2196 | if (!entry) | |
2197 | pr_warning("Could not create debugfs 'tracing_enabled' entry\n"); | |
2198 | ||
2199 | entry = debugfs_create_file("iter_ctrl", 0644, d_tracer, | |
2200 | NULL, &tracing_iter_fops); | |
2201 | if (!entry) | |
2202 | pr_warning("Could not create debugfs 'iter_ctrl' entry\n"); | |
2203 | ||
2204 | entry = debugfs_create_file("latency_trace", 0444, d_tracer, | |
2205 | &global_trace, &tracing_lt_fops); | |
2206 | if (!entry) | |
2207 | pr_warning("Could not create debugfs 'latency_trace' entry\n"); | |
2208 | ||
2209 | entry = debugfs_create_file("trace", 0444, d_tracer, | |
2210 | &global_trace, &tracing_fops); | |
2211 | if (!entry) | |
2212 | pr_warning("Could not create debugfs 'trace' entry\n"); | |
2213 | ||
2214 | entry = debugfs_create_file("available_tracers", 0444, d_tracer, | |
2215 | &global_trace, &show_traces_fops); | |
2216 | if (!entry) | |
2217 | pr_warning("Could not create debugfs 'trace' entry\n"); | |
2218 | ||
2219 | entry = debugfs_create_file("current_tracer", 0444, d_tracer, | |
2220 | &global_trace, &set_tracer_fops); | |
2221 | if (!entry) | |
2222 | pr_warning("Could not create debugfs 'trace' entry\n"); | |
2223 | ||
2224 | entry = debugfs_create_file("tracing_max_latency", 0644, d_tracer, | |
2225 | &tracing_max_latency, | |
2226 | &tracing_max_lat_fops); | |
2227 | if (!entry) | |
2228 | pr_warning("Could not create debugfs " | |
2229 | "'tracing_max_latency' entry\n"); | |
2230 | ||
2231 | entry = debugfs_create_file("tracing_thresh", 0644, d_tracer, | |
2232 | &tracing_thresh, &tracing_max_lat_fops); | |
2233 | if (!entry) | |
2234 | pr_warning("Could not create debugfs " | |
2235 | "'tracing_threash' entry\n"); | |
7bd2f24c IM |
2236 | entry = debugfs_create_file("README", 0644, d_tracer, |
2237 | NULL, &tracing_readme_fops); | |
2238 | if (!entry) | |
2239 | pr_warning("Could not create debugfs 'README' entry\n"); | |
2240 | ||
b3806b43 SR |
2241 | entry = debugfs_create_file("trace_pipe", 0644, d_tracer, |
2242 | NULL, &tracing_pipe_fops); | |
2243 | if (!entry) | |
2244 | pr_warning("Could not create debugfs " | |
2245 | "'tracing_threash' entry\n"); | |
bc0c38d1 SR |
2246 | |
2247 | #ifdef CONFIG_DYNAMIC_FTRACE | |
2248 | entry = debugfs_create_file("dyn_ftrace_total_info", 0444, d_tracer, | |
2249 | &ftrace_update_tot_cnt, | |
2250 | &tracing_read_long_fops); | |
2251 | if (!entry) | |
2252 | pr_warning("Could not create debugfs " | |
2253 | "'dyn_ftrace_total_info' entry\n"); | |
2254 | #endif | |
2255 | } | |
2256 | ||
2257 | /* dummy trace to disable tracing */ | |
2258 | static struct tracer no_tracer __read_mostly = | |
2259 | { | |
4bf39a94 | 2260 | .name = "none", |
bc0c38d1 SR |
2261 | }; |
2262 | ||
4c11d7ae | 2263 | static int trace_alloc_page(void) |
bc0c38d1 | 2264 | { |
4c11d7ae | 2265 | struct trace_array_cpu *data; |
4c11d7ae SR |
2266 | struct page *page, *tmp; |
2267 | LIST_HEAD(pages); | |
c7aafc54 | 2268 | void *array; |
4c11d7ae SR |
2269 | int i; |
2270 | ||
2271 | /* first allocate a page for each CPU */ | |
2272 | for_each_possible_cpu(i) { | |
2273 | array = (void *)__get_free_page(GFP_KERNEL); | |
2274 | if (array == NULL) { | |
2275 | printk(KERN_ERR "tracer: failed to allocate page" | |
2276 | "for trace buffer!\n"); | |
2277 | goto free_pages; | |
2278 | } | |
2279 | ||
2280 | page = virt_to_page(array); | |
2281 | list_add(&page->lru, &pages); | |
2282 | ||
2283 | /* Only allocate if we are actually using the max trace */ | |
2284 | #ifdef CONFIG_TRACER_MAX_TRACE | |
2285 | array = (void *)__get_free_page(GFP_KERNEL); | |
2286 | if (array == NULL) { | |
2287 | printk(KERN_ERR "tracer: failed to allocate page" | |
2288 | "for trace buffer!\n"); | |
2289 | goto free_pages; | |
2290 | } | |
2291 | page = virt_to_page(array); | |
2292 | list_add(&page->lru, &pages); | |
2293 | #endif | |
2294 | } | |
2295 | ||
2296 | /* Now that we successfully allocate a page per CPU, add them */ | |
2297 | for_each_possible_cpu(i) { | |
2298 | data = global_trace.data[i]; | |
b3806b43 | 2299 | spin_lock_init(&data->lock); |
d4c5a2f5 | 2300 | lockdep_set_class(&data->lock, &data->lock_key); |
4c11d7ae | 2301 | page = list_entry(pages.next, struct page, lru); |
c7aafc54 | 2302 | list_del_init(&page->lru); |
4c11d7ae SR |
2303 | list_add_tail(&page->lru, &data->trace_pages); |
2304 | ClearPageLRU(page); | |
2305 | ||
2306 | #ifdef CONFIG_TRACER_MAX_TRACE | |
2307 | data = max_tr.data[i]; | |
b3806b43 | 2308 | spin_lock_init(&data->lock); |
d4c5a2f5 | 2309 | lockdep_set_class(&data->lock, &data->lock_key); |
4c11d7ae | 2310 | page = list_entry(pages.next, struct page, lru); |
c7aafc54 | 2311 | list_del_init(&page->lru); |
4c11d7ae SR |
2312 | list_add_tail(&page->lru, &data->trace_pages); |
2313 | SetPageLRU(page); | |
2314 | #endif | |
2315 | } | |
2316 | global_trace.entries += ENTRIES_PER_PAGE; | |
2317 | ||
2318 | return 0; | |
2319 | ||
2320 | free_pages: | |
2321 | list_for_each_entry_safe(page, tmp, &pages, lru) { | |
c7aafc54 | 2322 | list_del_init(&page->lru); |
4c11d7ae SR |
2323 | __free_page(page); |
2324 | } | |
2325 | return -ENOMEM; | |
bc0c38d1 SR |
2326 | } |
2327 | ||
2328 | __init static int tracer_alloc_buffers(void) | |
2329 | { | |
4c11d7ae SR |
2330 | struct trace_array_cpu *data; |
2331 | void *array; | |
2332 | struct page *page; | |
2333 | int pages = 0; | |
60a11774 | 2334 | int ret = -ENOMEM; |
bc0c38d1 SR |
2335 | int i; |
2336 | ||
26994ead SR |
2337 | global_trace.ctrl = tracer_enabled; |
2338 | ||
4c11d7ae | 2339 | /* Allocate the first page for all buffers */ |
bc0c38d1 | 2340 | for_each_possible_cpu(i) { |
4c11d7ae | 2341 | data = global_trace.data[i] = &per_cpu(global_trace_cpu, i); |
bc0c38d1 SR |
2342 | max_tr.data[i] = &per_cpu(max_data, i); |
2343 | ||
4c11d7ae | 2344 | array = (void *)__get_free_page(GFP_KERNEL); |
bc0c38d1 | 2345 | if (array == NULL) { |
4c11d7ae SR |
2346 | printk(KERN_ERR "tracer: failed to allocate page" |
2347 | "for trace buffer!\n"); | |
bc0c38d1 SR |
2348 | goto free_buffers; |
2349 | } | |
4c11d7ae SR |
2350 | |
2351 | /* set the array to the list */ | |
2352 | INIT_LIST_HEAD(&data->trace_pages); | |
2353 | page = virt_to_page(array); | |
2354 | list_add(&page->lru, &data->trace_pages); | |
2355 | /* use the LRU flag to differentiate the two buffers */ | |
2356 | ClearPageLRU(page); | |
bc0c38d1 SR |
2357 | |
2358 | /* Only allocate if we are actually using the max trace */ | |
2359 | #ifdef CONFIG_TRACER_MAX_TRACE | |
4c11d7ae | 2360 | array = (void *)__get_free_page(GFP_KERNEL); |
bc0c38d1 | 2361 | if (array == NULL) { |
4c11d7ae SR |
2362 | printk(KERN_ERR "tracer: failed to allocate page" |
2363 | "for trace buffer!\n"); | |
bc0c38d1 SR |
2364 | goto free_buffers; |
2365 | } | |
4c11d7ae SR |
2366 | |
2367 | INIT_LIST_HEAD(&max_tr.data[i]->trace_pages); | |
2368 | page = virt_to_page(array); | |
2369 | list_add(&page->lru, &max_tr.data[i]->trace_pages); | |
2370 | SetPageLRU(page); | |
bc0c38d1 SR |
2371 | #endif |
2372 | } | |
2373 | ||
2374 | /* | |
2375 | * Since we allocate by orders of pages, we may be able to | |
2376 | * round up a bit. | |
2377 | */ | |
4c11d7ae | 2378 | global_trace.entries = ENTRIES_PER_PAGE; |
4c11d7ae SR |
2379 | pages++; |
2380 | ||
2381 | while (global_trace.entries < trace_nr_entries) { | |
2382 | if (trace_alloc_page()) | |
2383 | break; | |
2384 | pages++; | |
2385 | } | |
89b2f978 | 2386 | max_tr.entries = global_trace.entries; |
bc0c38d1 | 2387 | |
4c11d7ae SR |
2388 | pr_info("tracer: %d pages allocated for %ld", |
2389 | pages, trace_nr_entries); | |
bc0c38d1 SR |
2390 | pr_info(" entries of %ld bytes\n", (long)TRACE_ENTRY_SIZE); |
2391 | pr_info(" actual entries %ld\n", global_trace.entries); | |
2392 | ||
2393 | tracer_init_debugfs(); | |
2394 | ||
2395 | trace_init_cmdlines(); | |
2396 | ||
2397 | register_tracer(&no_tracer); | |
2398 | current_trace = &no_tracer; | |
2399 | ||
60a11774 SR |
2400 | /* All seems OK, enable tracing */ |
2401 | tracing_disabled = 0; | |
2402 | ||
bc0c38d1 SR |
2403 | return 0; |
2404 | ||
2405 | free_buffers: | |
2406 | for (i-- ; i >= 0; i--) { | |
4c11d7ae | 2407 | struct page *page, *tmp; |
bc0c38d1 SR |
2408 | struct trace_array_cpu *data = global_trace.data[i]; |
2409 | ||
c7aafc54 | 2410 | if (data) { |
4c11d7ae SR |
2411 | list_for_each_entry_safe(page, tmp, |
2412 | &data->trace_pages, lru) { | |
c7aafc54 | 2413 | list_del_init(&page->lru); |
4c11d7ae SR |
2414 | __free_page(page); |
2415 | } | |
bc0c38d1 SR |
2416 | } |
2417 | ||
2418 | #ifdef CONFIG_TRACER_MAX_TRACE | |
2419 | data = max_tr.data[i]; | |
c7aafc54 | 2420 | if (data) { |
4c11d7ae SR |
2421 | list_for_each_entry_safe(page, tmp, |
2422 | &data->trace_pages, lru) { | |
c7aafc54 | 2423 | list_del_init(&page->lru); |
4c11d7ae SR |
2424 | __free_page(page); |
2425 | } | |
bc0c38d1 SR |
2426 | } |
2427 | #endif | |
2428 | } | |
60a11774 | 2429 | return ret; |
bc0c38d1 | 2430 | } |
60a11774 | 2431 | fs_initcall(tracer_alloc_buffers); |