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Commit | Line | Data |
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bc0c38d1 SR |
1 | /* |
2 | * ring buffer based function tracer | |
3 | * | |
4 | * Copyright (C) 2007-2008 Steven Rostedt <srostedt@redhat.com> | |
5 | * Copyright (C) 2008 Ingo Molnar <mingo@redhat.com> | |
6 | * | |
7 | * Originally taken from the RT patch by: | |
8 | * Arnaldo Carvalho de Melo <acme@redhat.com> | |
9 | * | |
10 | * Based on code from the latency_tracer, that is: | |
11 | * Copyright (C) 2004-2006 Ingo Molnar | |
12 | * Copyright (C) 2004 William Lee Irwin III | |
13 | */ | |
14 | #include <linux/utsrelease.h> | |
15 | #include <linux/kallsyms.h> | |
16 | #include <linux/seq_file.h> | |
17 | #include <linux/debugfs.h> | |
4c11d7ae | 18 | #include <linux/pagemap.h> |
bc0c38d1 SR |
19 | #include <linux/hardirq.h> |
20 | #include <linux/linkage.h> | |
21 | #include <linux/uaccess.h> | |
22 | #include <linux/ftrace.h> | |
23 | #include <linux/module.h> | |
24 | #include <linux/percpu.h> | |
25 | #include <linux/ctype.h> | |
26 | #include <linux/init.h> | |
27 | #include <linux/gfp.h> | |
28 | #include <linux/fs.h> | |
29 | ||
30 | #include "trace.h" | |
31 | ||
32 | unsigned long __read_mostly tracing_max_latency = (cycle_t)ULONG_MAX; | |
33 | unsigned long __read_mostly tracing_thresh; | |
34 | ||
60a11774 SR |
35 | static int tracing_disabled = 1; |
36 | ||
bc0c38d1 SR |
37 | static long notrace |
38 | ns2usecs(cycle_t nsec) | |
39 | { | |
40 | nsec += 500; | |
41 | do_div(nsec, 1000); | |
42 | return nsec; | |
43 | } | |
44 | ||
53c37c17 IM |
45 | static const int time_sync_freq_max = 128; |
46 | static const cycle_t time_sync_thresh = 100000; | |
47 | ||
48 | static DEFINE_PER_CPU(cycle_t, time_offset); | |
49 | static DEFINE_PER_CPU(cycle_t, prev_cpu_time); | |
50 | static DEFINE_PER_CPU(int, time_sync_count); | |
51 | static DEFINE_PER_CPU(int, time_sync_freq); | |
52 | ||
53 | /* | |
54 | * Global lock which we take every now and then to synchronize | |
55 | * the CPUs time. This method is not warp-safe, but it's good | |
56 | * enough to synchronize slowly diverging time sources and thus | |
57 | * it's good enough for tracing: | |
58 | */ | |
59 | static DEFINE_SPINLOCK(time_sync_lock); | |
60 | static cycle_t prev_global_time; | |
61 | ||
62 | static notrace cycle_t __ftrace_now_sync(cycles_t time, int cpu) | |
63 | { | |
64 | unsigned long flags; | |
65 | ||
66 | spin_lock_irqsave(&time_sync_lock, flags); | |
67 | ||
68 | /* | |
69 | * Update the synchronization frequency: | |
70 | */ | |
71 | if (per_cpu(time_sync_freq, cpu) < time_sync_freq_max) | |
72 | per_cpu(time_sync_freq, cpu) *= 2; | |
73 | per_cpu(time_sync_count, cpu) = per_cpu(time_sync_freq, cpu); | |
74 | ||
75 | if (time < prev_global_time) { | |
76 | per_cpu(time_offset, cpu) += prev_global_time - time; | |
77 | time = prev_global_time; | |
78 | } else { | |
79 | prev_global_time = time; | |
80 | } | |
81 | ||
82 | spin_unlock_irqrestore(&time_sync_lock, flags); | |
83 | ||
84 | return time; | |
85 | } | |
86 | ||
750ed1a4 IM |
87 | notrace cycle_t ftrace_now(int cpu) |
88 | { | |
53c37c17 IM |
89 | cycle_t prev_cpu_time, time, delta_time; |
90 | ||
91 | prev_cpu_time = per_cpu(prev_cpu_time, cpu); | |
92 | time = sched_clock() + per_cpu(time_offset, cpu); | |
93 | delta_time = time-prev_cpu_time; | |
94 | ||
95 | if (unlikely(delta_time > time_sync_thresh || | |
96 | --per_cpu(time_sync_count, cpu) <= 0)) | |
97 | time = __ftrace_now_sync(time, cpu); | |
98 | ||
99 | return time; | |
750ed1a4 IM |
100 | } |
101 | ||
bc0c38d1 SR |
102 | static struct trace_array global_trace; |
103 | ||
104 | static DEFINE_PER_CPU(struct trace_array_cpu, global_trace_cpu); | |
105 | ||
106 | static struct trace_array max_tr; | |
107 | ||
108 | static DEFINE_PER_CPU(struct trace_array_cpu, max_data); | |
109 | ||
110 | static int tracer_enabled; | |
4c11d7ae | 111 | static unsigned long trace_nr_entries = 16384UL; |
bc0c38d1 SR |
112 | |
113 | static struct tracer *trace_types __read_mostly; | |
114 | static struct tracer *current_trace __read_mostly; | |
115 | static int max_tracer_type_len; | |
116 | ||
117 | static DEFINE_MUTEX(trace_types_lock); | |
118 | ||
4c11d7ae SR |
119 | #define ENTRIES_PER_PAGE (PAGE_SIZE / sizeof(struct trace_entry)) |
120 | ||
bc0c38d1 SR |
121 | static int __init set_nr_entries(char *str) |
122 | { | |
123 | if (!str) | |
124 | return 0; | |
125 | trace_nr_entries = simple_strtoul(str, &str, 0); | |
126 | return 1; | |
127 | } | |
128 | __setup("trace_entries=", set_nr_entries); | |
129 | ||
57f50be1 SR |
130 | unsigned long nsecs_to_usecs(unsigned long nsecs) |
131 | { | |
132 | return nsecs / 1000; | |
133 | } | |
134 | ||
bc0c38d1 SR |
135 | enum trace_type { |
136 | __TRACE_FIRST_TYPE = 0, | |
137 | ||
138 | TRACE_FN, | |
139 | TRACE_CTX, | |
f0a920d5 | 140 | TRACE_SPECIAL, |
bc0c38d1 SR |
141 | |
142 | __TRACE_LAST_TYPE | |
143 | }; | |
144 | ||
145 | enum trace_flag_type { | |
146 | TRACE_FLAG_IRQS_OFF = 0x01, | |
147 | TRACE_FLAG_NEED_RESCHED = 0x02, | |
148 | TRACE_FLAG_HARDIRQ = 0x04, | |
149 | TRACE_FLAG_SOFTIRQ = 0x08, | |
150 | }; | |
151 | ||
152 | enum trace_iterator_flags { | |
153 | TRACE_ITER_PRINT_PARENT = 0x01, | |
154 | TRACE_ITER_SYM_OFFSET = 0x02, | |
155 | TRACE_ITER_SYM_ADDR = 0x04, | |
156 | TRACE_ITER_VERBOSE = 0x08, | |
f9896bf3 | 157 | TRACE_ITER_RAW = 0x10, |
cb0f12aa | 158 | TRACE_ITER_BIN = 0x20, |
bc0c38d1 SR |
159 | }; |
160 | ||
161 | #define TRACE_ITER_SYM_MASK \ | |
162 | (TRACE_ITER_PRINT_PARENT|TRACE_ITER_SYM_OFFSET|TRACE_ITER_SYM_ADDR) | |
163 | ||
164 | /* These must match the bit postions above */ | |
165 | static const char *trace_options[] = { | |
166 | "print-parent", | |
167 | "sym-offset", | |
168 | "sym-addr", | |
169 | "verbose", | |
f9896bf3 | 170 | "raw", |
cb0f12aa | 171 | "bin", |
bc0c38d1 SR |
172 | NULL |
173 | }; | |
174 | ||
175 | static unsigned trace_flags; | |
176 | ||
4c11d7ae | 177 | static DEFINE_SPINLOCK(ftrace_max_lock); |
bc0c38d1 SR |
178 | |
179 | /* | |
180 | * Copy the new maximum trace into the separate maximum-trace | |
181 | * structure. (this way the maximum trace is permanently saved, | |
182 | * for later retrieval via /debugfs/tracing/latency_trace) | |
183 | */ | |
4e3c3333 | 184 | static notrace void |
bc0c38d1 SR |
185 | __update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) |
186 | { | |
187 | struct trace_array_cpu *data = tr->data[cpu]; | |
188 | ||
189 | max_tr.cpu = cpu; | |
190 | max_tr.time_start = data->preempt_timestamp; | |
191 | ||
192 | data = max_tr.data[cpu]; | |
193 | data->saved_latency = tracing_max_latency; | |
194 | ||
195 | memcpy(data->comm, tsk->comm, TASK_COMM_LEN); | |
196 | data->pid = tsk->pid; | |
197 | data->uid = tsk->uid; | |
198 | data->nice = tsk->static_prio - 20 - MAX_RT_PRIO; | |
199 | data->policy = tsk->policy; | |
200 | data->rt_priority = tsk->rt_priority; | |
201 | ||
202 | /* record this tasks comm */ | |
203 | tracing_record_cmdline(current); | |
204 | } | |
205 | ||
c7aafc54 IM |
206 | void check_pages(struct trace_array_cpu *data) |
207 | { | |
208 | struct page *page, *tmp; | |
209 | ||
210 | BUG_ON(data->trace_pages.next->prev != &data->trace_pages); | |
211 | BUG_ON(data->trace_pages.prev->next != &data->trace_pages); | |
212 | ||
213 | list_for_each_entry_safe(page, tmp, &data->trace_pages, lru) { | |
214 | BUG_ON(page->lru.next->prev != &page->lru); | |
215 | BUG_ON(page->lru.prev->next != &page->lru); | |
216 | } | |
217 | } | |
218 | ||
219 | void *head_page(struct trace_array_cpu *data) | |
220 | { | |
221 | struct page *page; | |
222 | ||
223 | check_pages(data); | |
224 | if (list_empty(&data->trace_pages)) | |
225 | return NULL; | |
226 | ||
227 | page = list_entry(data->trace_pages.next, struct page, lru); | |
228 | BUG_ON(&page->lru == &data->trace_pages); | |
229 | ||
230 | return page_address(page); | |
231 | } | |
232 | ||
214023c3 SR |
233 | static notrace int |
234 | trace_seq_printf(struct trace_seq *s, const char *fmt, ...) | |
235 | { | |
236 | int len = (PAGE_SIZE - 1) - s->len; | |
237 | va_list ap; | |
b3806b43 | 238 | int ret; |
214023c3 SR |
239 | |
240 | if (!len) | |
241 | return 0; | |
242 | ||
243 | va_start(ap, fmt); | |
b3806b43 | 244 | ret = vsnprintf(s->buffer + s->len, len, fmt, ap); |
214023c3 SR |
245 | va_end(ap); |
246 | ||
b3806b43 SR |
247 | /* If we can't write it all, don't bother writing anything */ |
248 | if (ret > len) | |
249 | return 0; | |
250 | ||
251 | s->len += ret; | |
214023c3 SR |
252 | |
253 | return len; | |
254 | } | |
255 | ||
256 | static notrace int | |
257 | trace_seq_puts(struct trace_seq *s, const char *str) | |
258 | { | |
259 | int len = strlen(str); | |
260 | ||
261 | if (len > ((PAGE_SIZE - 1) - s->len)) | |
b3806b43 | 262 | return 0; |
214023c3 SR |
263 | |
264 | memcpy(s->buffer + s->len, str, len); | |
265 | s->len += len; | |
266 | ||
267 | return len; | |
268 | } | |
269 | ||
270 | static notrace int | |
271 | trace_seq_putc(struct trace_seq *s, unsigned char c) | |
272 | { | |
273 | if (s->len >= (PAGE_SIZE - 1)) | |
274 | return 0; | |
275 | ||
276 | s->buffer[s->len++] = c; | |
277 | ||
278 | return 1; | |
279 | } | |
280 | ||
cb0f12aa IM |
281 | static notrace int |
282 | trace_seq_putmem(struct trace_seq *s, void *mem, size_t len) | |
283 | { | |
284 | if (len > ((PAGE_SIZE - 1) - s->len)) | |
285 | return 0; | |
286 | ||
287 | memcpy(s->buffer + s->len, mem, len); | |
288 | s->len += len; | |
289 | ||
290 | return len; | |
291 | } | |
292 | ||
214023c3 SR |
293 | static notrace void |
294 | trace_seq_reset(struct trace_seq *s) | |
295 | { | |
296 | s->len = 0; | |
297 | } | |
298 | ||
299 | static notrace void | |
300 | trace_print_seq(struct seq_file *m, struct trace_seq *s) | |
301 | { | |
302 | int len = s->len >= PAGE_SIZE ? PAGE_SIZE - 1 : s->len; | |
303 | ||
304 | s->buffer[len] = 0; | |
305 | seq_puts(m, s->buffer); | |
306 | ||
307 | trace_seq_reset(s); | |
308 | } | |
309 | ||
c7aafc54 IM |
310 | notrace static void |
311 | flip_trace(struct trace_array_cpu *tr1, struct trace_array_cpu *tr2) | |
312 | { | |
313 | struct list_head flip_pages; | |
314 | ||
315 | INIT_LIST_HEAD(&flip_pages); | |
316 | ||
93a588f4 | 317 | memcpy(&tr1->trace_head_idx, &tr2->trace_head_idx, |
c7aafc54 | 318 | sizeof(struct trace_array_cpu) - |
93a588f4 | 319 | offsetof(struct trace_array_cpu, trace_head_idx)); |
c7aafc54 IM |
320 | |
321 | check_pages(tr1); | |
322 | check_pages(tr2); | |
323 | list_splice_init(&tr1->trace_pages, &flip_pages); | |
324 | list_splice_init(&tr2->trace_pages, &tr1->trace_pages); | |
325 | list_splice_init(&flip_pages, &tr2->trace_pages); | |
326 | BUG_ON(!list_empty(&flip_pages)); | |
327 | check_pages(tr1); | |
328 | check_pages(tr2); | |
329 | } | |
330 | ||
bc0c38d1 SR |
331 | notrace void |
332 | update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) | |
333 | { | |
334 | struct trace_array_cpu *data; | |
bc0c38d1 SR |
335 | int i; |
336 | ||
4c11d7ae SR |
337 | WARN_ON_ONCE(!irqs_disabled()); |
338 | spin_lock(&ftrace_max_lock); | |
bc0c38d1 SR |
339 | /* clear out all the previous traces */ |
340 | for_each_possible_cpu(i) { | |
341 | data = tr->data[i]; | |
c7aafc54 | 342 | flip_trace(max_tr.data[i], data); |
89b2f978 | 343 | tracing_reset(data); |
bc0c38d1 SR |
344 | } |
345 | ||
346 | __update_max_tr(tr, tsk, cpu); | |
4c11d7ae | 347 | spin_unlock(&ftrace_max_lock); |
bc0c38d1 SR |
348 | } |
349 | ||
350 | /** | |
351 | * update_max_tr_single - only copy one trace over, and reset the rest | |
352 | * @tr - tracer | |
353 | * @tsk - task with the latency | |
354 | * @cpu - the cpu of the buffer to copy. | |
355 | */ | |
356 | notrace void | |
357 | update_max_tr_single(struct trace_array *tr, struct task_struct *tsk, int cpu) | |
358 | { | |
359 | struct trace_array_cpu *data = tr->data[cpu]; | |
bc0c38d1 SR |
360 | int i; |
361 | ||
4c11d7ae SR |
362 | WARN_ON_ONCE(!irqs_disabled()); |
363 | spin_lock(&ftrace_max_lock); | |
bc0c38d1 SR |
364 | for_each_possible_cpu(i) |
365 | tracing_reset(max_tr.data[i]); | |
366 | ||
c7aafc54 | 367 | flip_trace(max_tr.data[cpu], data); |
89b2f978 | 368 | tracing_reset(data); |
bc0c38d1 SR |
369 | |
370 | __update_max_tr(tr, tsk, cpu); | |
4c11d7ae | 371 | spin_unlock(&ftrace_max_lock); |
bc0c38d1 SR |
372 | } |
373 | ||
374 | int register_tracer(struct tracer *type) | |
375 | { | |
376 | struct tracer *t; | |
377 | int len; | |
378 | int ret = 0; | |
379 | ||
380 | if (!type->name) { | |
381 | pr_info("Tracer must have a name\n"); | |
382 | return -1; | |
383 | } | |
384 | ||
385 | mutex_lock(&trace_types_lock); | |
386 | for (t = trace_types; t; t = t->next) { | |
387 | if (strcmp(type->name, t->name) == 0) { | |
388 | /* already found */ | |
389 | pr_info("Trace %s already registered\n", | |
390 | type->name); | |
391 | ret = -1; | |
392 | goto out; | |
393 | } | |
394 | } | |
395 | ||
60a11774 SR |
396 | #ifdef CONFIG_FTRACE_STARTUP_TEST |
397 | if (type->selftest) { | |
398 | struct tracer *saved_tracer = current_trace; | |
399 | struct trace_array_cpu *data; | |
400 | struct trace_array *tr = &global_trace; | |
401 | int saved_ctrl = tr->ctrl; | |
402 | int i; | |
403 | /* | |
404 | * Run a selftest on this tracer. | |
405 | * Here we reset the trace buffer, and set the current | |
406 | * tracer to be this tracer. The tracer can then run some | |
407 | * internal tracing to verify that everything is in order. | |
408 | * If we fail, we do not register this tracer. | |
409 | */ | |
410 | for_each_possible_cpu(i) { | |
60a11774 | 411 | data = tr->data[i]; |
c7aafc54 IM |
412 | if (!head_page(data)) |
413 | continue; | |
60a11774 SR |
414 | tracing_reset(data); |
415 | } | |
416 | current_trace = type; | |
417 | tr->ctrl = 0; | |
418 | /* the test is responsible for initializing and enabling */ | |
419 | pr_info("Testing tracer %s: ", type->name); | |
420 | ret = type->selftest(type, tr); | |
421 | /* the test is responsible for resetting too */ | |
422 | current_trace = saved_tracer; | |
423 | tr->ctrl = saved_ctrl; | |
424 | if (ret) { | |
425 | printk(KERN_CONT "FAILED!\n"); | |
426 | goto out; | |
427 | } | |
1d4db00a SR |
428 | /* Only reset on passing, to avoid touching corrupted buffers */ |
429 | for_each_possible_cpu(i) { | |
430 | data = tr->data[i]; | |
431 | if (!head_page(data)) | |
432 | continue; | |
433 | tracing_reset(data); | |
434 | } | |
60a11774 SR |
435 | printk(KERN_CONT "PASSED\n"); |
436 | } | |
437 | #endif | |
438 | ||
bc0c38d1 SR |
439 | type->next = trace_types; |
440 | trace_types = type; | |
441 | len = strlen(type->name); | |
442 | if (len > max_tracer_type_len) | |
443 | max_tracer_type_len = len; | |
60a11774 | 444 | |
bc0c38d1 SR |
445 | out: |
446 | mutex_unlock(&trace_types_lock); | |
447 | ||
448 | return ret; | |
449 | } | |
450 | ||
451 | void unregister_tracer(struct tracer *type) | |
452 | { | |
453 | struct tracer **t; | |
454 | int len; | |
455 | ||
456 | mutex_lock(&trace_types_lock); | |
457 | for (t = &trace_types; *t; t = &(*t)->next) { | |
458 | if (*t == type) | |
459 | goto found; | |
460 | } | |
461 | pr_info("Trace %s not registered\n", type->name); | |
462 | goto out; | |
463 | ||
464 | found: | |
465 | *t = (*t)->next; | |
466 | if (strlen(type->name) != max_tracer_type_len) | |
467 | goto out; | |
468 | ||
469 | max_tracer_type_len = 0; | |
470 | for (t = &trace_types; *t; t = &(*t)->next) { | |
471 | len = strlen((*t)->name); | |
472 | if (len > max_tracer_type_len) | |
473 | max_tracer_type_len = len; | |
474 | } | |
475 | out: | |
476 | mutex_unlock(&trace_types_lock); | |
477 | } | |
478 | ||
4e3c3333 | 479 | notrace void tracing_reset(struct trace_array_cpu *data) |
bc0c38d1 SR |
480 | { |
481 | data->trace_idx = 0; | |
93a588f4 SR |
482 | data->trace_head = data->trace_tail = head_page(data); |
483 | data->trace_head_idx = 0; | |
484 | data->trace_tail_idx = 0; | |
bc0c38d1 SR |
485 | } |
486 | ||
487 | #ifdef CONFIG_FTRACE | |
4e3c3333 | 488 | static notrace void |
bc0c38d1 SR |
489 | function_trace_call(unsigned long ip, unsigned long parent_ip) |
490 | { | |
491 | struct trace_array *tr = &global_trace; | |
492 | struct trace_array_cpu *data; | |
493 | unsigned long flags; | |
494 | long disabled; | |
495 | int cpu; | |
496 | ||
497 | if (unlikely(!tracer_enabled)) | |
498 | return; | |
499 | ||
18cef379 | 500 | local_irq_save(flags); |
bc0c38d1 SR |
501 | cpu = raw_smp_processor_id(); |
502 | data = tr->data[cpu]; | |
503 | disabled = atomic_inc_return(&data->disabled); | |
504 | ||
505 | if (likely(disabled == 1)) | |
506 | ftrace(tr, data, ip, parent_ip, flags); | |
507 | ||
508 | atomic_dec(&data->disabled); | |
18cef379 | 509 | local_irq_restore(flags); |
bc0c38d1 SR |
510 | } |
511 | ||
512 | static struct ftrace_ops trace_ops __read_mostly = | |
513 | { | |
514 | .func = function_trace_call, | |
515 | }; | |
516 | #endif | |
517 | ||
518 | notrace void tracing_start_function_trace(void) | |
519 | { | |
520 | register_ftrace_function(&trace_ops); | |
521 | } | |
522 | ||
523 | notrace void tracing_stop_function_trace(void) | |
524 | { | |
525 | unregister_ftrace_function(&trace_ops); | |
526 | } | |
527 | ||
528 | #define SAVED_CMDLINES 128 | |
529 | static unsigned map_pid_to_cmdline[PID_MAX_DEFAULT+1]; | |
530 | static unsigned map_cmdline_to_pid[SAVED_CMDLINES]; | |
531 | static char saved_cmdlines[SAVED_CMDLINES][TASK_COMM_LEN]; | |
532 | static int cmdline_idx; | |
533 | static DEFINE_SPINLOCK(trace_cmdline_lock); | |
534 | atomic_t trace_record_cmdline_disabled; | |
535 | ||
536 | static void trace_init_cmdlines(void) | |
537 | { | |
538 | memset(&map_pid_to_cmdline, -1, sizeof(map_pid_to_cmdline)); | |
539 | memset(&map_cmdline_to_pid, -1, sizeof(map_cmdline_to_pid)); | |
540 | cmdline_idx = 0; | |
541 | } | |
542 | ||
543 | notrace void trace_stop_cmdline_recording(void); | |
544 | ||
4e3c3333 | 545 | static notrace void trace_save_cmdline(struct task_struct *tsk) |
bc0c38d1 SR |
546 | { |
547 | unsigned map; | |
548 | unsigned idx; | |
549 | ||
550 | if (!tsk->pid || unlikely(tsk->pid > PID_MAX_DEFAULT)) | |
551 | return; | |
552 | ||
553 | /* | |
554 | * It's not the end of the world if we don't get | |
555 | * the lock, but we also don't want to spin | |
556 | * nor do we want to disable interrupts, | |
557 | * so if we miss here, then better luck next time. | |
558 | */ | |
559 | if (!spin_trylock(&trace_cmdline_lock)) | |
560 | return; | |
561 | ||
562 | idx = map_pid_to_cmdline[tsk->pid]; | |
563 | if (idx >= SAVED_CMDLINES) { | |
564 | idx = (cmdline_idx + 1) % SAVED_CMDLINES; | |
565 | ||
566 | map = map_cmdline_to_pid[idx]; | |
567 | if (map <= PID_MAX_DEFAULT) | |
568 | map_pid_to_cmdline[map] = (unsigned)-1; | |
569 | ||
570 | map_pid_to_cmdline[tsk->pid] = idx; | |
571 | ||
572 | cmdline_idx = idx; | |
573 | } | |
574 | ||
575 | memcpy(&saved_cmdlines[idx], tsk->comm, TASK_COMM_LEN); | |
576 | ||
577 | spin_unlock(&trace_cmdline_lock); | |
578 | } | |
579 | ||
580 | static notrace char *trace_find_cmdline(int pid) | |
581 | { | |
582 | char *cmdline = "<...>"; | |
583 | unsigned map; | |
584 | ||
585 | if (!pid) | |
586 | return "<idle>"; | |
587 | ||
588 | if (pid > PID_MAX_DEFAULT) | |
589 | goto out; | |
590 | ||
591 | map = map_pid_to_cmdline[pid]; | |
592 | if (map >= SAVED_CMDLINES) | |
593 | goto out; | |
594 | ||
595 | cmdline = saved_cmdlines[map]; | |
596 | ||
597 | out: | |
598 | return cmdline; | |
599 | } | |
600 | ||
601 | notrace void tracing_record_cmdline(struct task_struct *tsk) | |
602 | { | |
603 | if (atomic_read(&trace_record_cmdline_disabled)) | |
604 | return; | |
605 | ||
606 | trace_save_cmdline(tsk); | |
607 | } | |
608 | ||
93a588f4 SR |
609 | static inline notrace struct list_head * |
610 | trace_next_list(struct trace_array_cpu *data, struct list_head *next) | |
611 | { | |
612 | /* | |
613 | * Roundrobin - but skip the head (which is not a real page): | |
614 | */ | |
615 | next = next->next; | |
616 | if (unlikely(next == &data->trace_pages)) | |
617 | next = next->next; | |
618 | BUG_ON(next == &data->trace_pages); | |
619 | ||
620 | return next; | |
621 | } | |
622 | ||
623 | static inline notrace void * | |
624 | trace_next_page(struct trace_array_cpu *data, void *addr) | |
625 | { | |
626 | struct list_head *next; | |
627 | struct page *page; | |
628 | ||
629 | page = virt_to_page(addr); | |
630 | ||
631 | next = trace_next_list(data, &page->lru); | |
632 | page = list_entry(next, struct page, lru); | |
633 | ||
634 | return page_address(page); | |
635 | } | |
636 | ||
bc0c38d1 | 637 | static inline notrace struct trace_entry * |
c7aafc54 | 638 | tracing_get_trace_entry(struct trace_array *tr, struct trace_array_cpu *data) |
bc0c38d1 SR |
639 | { |
640 | unsigned long idx, idx_next; | |
641 | struct trace_entry *entry; | |
642 | ||
4c11d7ae | 643 | data->trace_idx++; |
93a588f4 | 644 | idx = data->trace_head_idx; |
bc0c38d1 SR |
645 | idx_next = idx + 1; |
646 | ||
c7aafc54 IM |
647 | BUG_ON(idx * TRACE_ENTRY_SIZE >= PAGE_SIZE); |
648 | ||
93a588f4 | 649 | entry = data->trace_head + idx * TRACE_ENTRY_SIZE; |
4c11d7ae SR |
650 | |
651 | if (unlikely(idx_next >= ENTRIES_PER_PAGE)) { | |
93a588f4 | 652 | data->trace_head = trace_next_page(data, data->trace_head); |
bc0c38d1 SR |
653 | idx_next = 0; |
654 | } | |
655 | ||
93a588f4 SR |
656 | if (data->trace_head == data->trace_tail && |
657 | idx_next == data->trace_tail_idx) { | |
658 | /* overrun */ | |
659 | data->trace_tail_idx++; | |
660 | if (data->trace_tail_idx >= ENTRIES_PER_PAGE) { | |
661 | data->trace_tail = | |
662 | trace_next_page(data, data->trace_tail); | |
663 | data->trace_tail_idx = 0; | |
664 | } | |
665 | } | |
666 | ||
667 | data->trace_head_idx = idx_next; | |
bc0c38d1 SR |
668 | |
669 | return entry; | |
670 | } | |
671 | ||
672 | static inline notrace void | |
c7aafc54 | 673 | tracing_generic_entry_update(struct trace_entry *entry, unsigned long flags) |
bc0c38d1 SR |
674 | { |
675 | struct task_struct *tsk = current; | |
676 | unsigned long pc; | |
677 | ||
678 | pc = preempt_count(); | |
679 | ||
c7aafc54 IM |
680 | entry->preempt_count = pc & 0xff; |
681 | entry->pid = tsk->pid; | |
750ed1a4 | 682 | entry->t = ftrace_now(raw_smp_processor_id()); |
bc0c38d1 SR |
683 | entry->flags = (irqs_disabled_flags(flags) ? TRACE_FLAG_IRQS_OFF : 0) | |
684 | ((pc & HARDIRQ_MASK) ? TRACE_FLAG_HARDIRQ : 0) | | |
685 | ((pc & SOFTIRQ_MASK) ? TRACE_FLAG_SOFTIRQ : 0) | | |
686 | (need_resched() ? TRACE_FLAG_NEED_RESCHED : 0); | |
687 | } | |
688 | ||
689 | notrace void | |
690 | ftrace(struct trace_array *tr, struct trace_array_cpu *data, | |
c7aafc54 | 691 | unsigned long ip, unsigned long parent_ip, unsigned long flags) |
bc0c38d1 SR |
692 | { |
693 | struct trace_entry *entry; | |
dcb6308f | 694 | unsigned long irq_flags; |
bc0c38d1 | 695 | |
dcb6308f | 696 | spin_lock_irqsave(&data->lock, irq_flags); |
c7aafc54 | 697 | entry = tracing_get_trace_entry(tr, data); |
bc0c38d1 | 698 | tracing_generic_entry_update(entry, flags); |
c7aafc54 IM |
699 | entry->type = TRACE_FN; |
700 | entry->fn.ip = ip; | |
701 | entry->fn.parent_ip = parent_ip; | |
dcb6308f | 702 | spin_unlock_irqrestore(&data->lock, irq_flags); |
bc0c38d1 SR |
703 | } |
704 | ||
f0a920d5 IM |
705 | notrace void |
706 | trace_special(struct trace_array *tr, struct trace_array_cpu *data, | |
707 | unsigned long arg1, unsigned long arg2, unsigned long arg3) | |
708 | { | |
709 | struct trace_entry *entry; | |
dcb6308f | 710 | unsigned long irq_flags; |
f0a920d5 | 711 | |
dcb6308f | 712 | spin_lock_irqsave(&data->lock, irq_flags); |
f0a920d5 IM |
713 | entry = tracing_get_trace_entry(tr, data); |
714 | tracing_generic_entry_update(entry, 0); | |
715 | entry->type = TRACE_SPECIAL; | |
716 | entry->special.arg1 = arg1; | |
717 | entry->special.arg2 = arg2; | |
718 | entry->special.arg3 = arg3; | |
dcb6308f | 719 | spin_unlock_irqrestore(&data->lock, irq_flags); |
f0a920d5 IM |
720 | } |
721 | ||
bc0c38d1 SR |
722 | notrace void |
723 | tracing_sched_switch_trace(struct trace_array *tr, | |
724 | struct trace_array_cpu *data, | |
725 | struct task_struct *prev, struct task_struct *next, | |
726 | unsigned long flags) | |
727 | { | |
728 | struct trace_entry *entry; | |
dcb6308f | 729 | unsigned long irq_flags; |
bc0c38d1 | 730 | |
dcb6308f | 731 | spin_lock_irqsave(&data->lock, irq_flags); |
c7aafc54 | 732 | entry = tracing_get_trace_entry(tr, data); |
bc0c38d1 SR |
733 | tracing_generic_entry_update(entry, flags); |
734 | entry->type = TRACE_CTX; | |
735 | entry->ctx.prev_pid = prev->pid; | |
736 | entry->ctx.prev_prio = prev->prio; | |
737 | entry->ctx.prev_state = prev->state; | |
738 | entry->ctx.next_pid = next->pid; | |
739 | entry->ctx.next_prio = next->prio; | |
dcb6308f | 740 | spin_unlock_irqrestore(&data->lock, irq_flags); |
bc0c38d1 SR |
741 | } |
742 | ||
743 | enum trace_file_type { | |
744 | TRACE_FILE_LAT_FMT = 1, | |
745 | }; | |
746 | ||
747 | static struct trace_entry * | |
4c11d7ae SR |
748 | trace_entry_idx(struct trace_array *tr, struct trace_array_cpu *data, |
749 | struct trace_iterator *iter, int cpu) | |
bc0c38d1 | 750 | { |
4c11d7ae SR |
751 | struct page *page; |
752 | struct trace_entry *array; | |
bc0c38d1 | 753 | |
4c11d7ae | 754 | if (iter->next_idx[cpu] >= tr->entries || |
b3806b43 SR |
755 | iter->next_idx[cpu] >= data->trace_idx || |
756 | (data->trace_head == data->trace_tail && | |
757 | data->trace_head_idx == data->trace_tail_idx)) | |
bc0c38d1 SR |
758 | return NULL; |
759 | ||
4c11d7ae | 760 | if (!iter->next_page[cpu]) { |
93a588f4 SR |
761 | /* Initialize the iterator for this cpu trace buffer */ |
762 | WARN_ON(!data->trace_tail); | |
763 | page = virt_to_page(data->trace_tail); | |
764 | iter->next_page[cpu] = &page->lru; | |
765 | iter->next_page_idx[cpu] = data->trace_tail_idx; | |
4c11d7ae | 766 | } |
bc0c38d1 | 767 | |
4c11d7ae | 768 | page = list_entry(iter->next_page[cpu], struct page, lru); |
c7aafc54 IM |
769 | BUG_ON(&data->trace_pages == &page->lru); |
770 | ||
4c11d7ae SR |
771 | array = page_address(page); |
772 | ||
93a588f4 | 773 | WARN_ON(iter->next_page_idx[cpu] >= ENTRIES_PER_PAGE); |
4c11d7ae | 774 | return &array[iter->next_page_idx[cpu]]; |
bc0c38d1 SR |
775 | } |
776 | ||
777 | static struct notrace trace_entry * | |
778 | find_next_entry(struct trace_iterator *iter, int *ent_cpu) | |
779 | { | |
780 | struct trace_array *tr = iter->tr; | |
781 | struct trace_entry *ent, *next = NULL; | |
782 | int next_cpu = -1; | |
783 | int cpu; | |
784 | ||
785 | for_each_possible_cpu(cpu) { | |
c7aafc54 | 786 | if (!head_page(tr->data[cpu])) |
bc0c38d1 | 787 | continue; |
4c11d7ae | 788 | ent = trace_entry_idx(tr, tr->data[cpu], iter, cpu); |
cdd31cd2 IM |
789 | /* |
790 | * Pick the entry with the smallest timestamp: | |
791 | */ | |
792 | if (ent && (!next || ent->t < next->t)) { | |
bc0c38d1 SR |
793 | next = ent; |
794 | next_cpu = cpu; | |
795 | } | |
796 | } | |
797 | ||
798 | if (ent_cpu) | |
799 | *ent_cpu = next_cpu; | |
800 | ||
801 | return next; | |
802 | } | |
803 | ||
8c523a9d | 804 | static notrace void trace_iterator_increment(struct trace_iterator *iter) |
bc0c38d1 | 805 | { |
b3806b43 SR |
806 | iter->idx++; |
807 | iter->next_idx[iter->cpu]++; | |
808 | iter->next_page_idx[iter->cpu]++; | |
8c523a9d | 809 | |
b3806b43 SR |
810 | if (iter->next_page_idx[iter->cpu] >= ENTRIES_PER_PAGE) { |
811 | struct trace_array_cpu *data = iter->tr->data[iter->cpu]; | |
bc0c38d1 | 812 | |
b3806b43 SR |
813 | iter->next_page_idx[iter->cpu] = 0; |
814 | iter->next_page[iter->cpu] = | |
815 | trace_next_list(data, iter->next_page[iter->cpu]); | |
816 | } | |
817 | } | |
bc0c38d1 | 818 | |
8c523a9d | 819 | static notrace void trace_consume(struct trace_iterator *iter) |
b3806b43 SR |
820 | { |
821 | struct trace_array_cpu *data = iter->tr->data[iter->cpu]; | |
822 | ||
823 | data->trace_tail_idx++; | |
824 | if (data->trace_tail_idx >= ENTRIES_PER_PAGE) { | |
825 | data->trace_tail = trace_next_page(data, data->trace_tail); | |
826 | data->trace_tail_idx = 0; | |
827 | } | |
4e3c3333 | 828 | |
b3806b43 SR |
829 | /* Check if we empty it, then reset the index */ |
830 | if (data->trace_head == data->trace_tail && | |
831 | data->trace_head_idx == data->trace_tail_idx) | |
832 | data->trace_idx = 0; | |
b3806b43 SR |
833 | } |
834 | ||
8c523a9d | 835 | static notrace void *find_next_entry_inc(struct trace_iterator *iter) |
b3806b43 SR |
836 | { |
837 | struct trace_entry *next; | |
838 | int next_cpu = -1; | |
839 | ||
840 | next = find_next_entry(iter, &next_cpu); | |
93a588f4 | 841 | |
4e3c3333 IM |
842 | iter->prev_ent = iter->ent; |
843 | iter->prev_cpu = iter->cpu; | |
844 | ||
bc0c38d1 SR |
845 | iter->ent = next; |
846 | iter->cpu = next_cpu; | |
847 | ||
b3806b43 SR |
848 | if (next) |
849 | trace_iterator_increment(iter); | |
850 | ||
bc0c38d1 SR |
851 | return next ? iter : NULL; |
852 | } | |
853 | ||
4e3c3333 | 854 | static notrace void *s_next(struct seq_file *m, void *v, loff_t *pos) |
bc0c38d1 SR |
855 | { |
856 | struct trace_iterator *iter = m->private; | |
bc0c38d1 SR |
857 | void *last_ent = iter->ent; |
858 | int i = (int)*pos; | |
4e3c3333 | 859 | void *ent; |
bc0c38d1 SR |
860 | |
861 | (*pos)++; | |
862 | ||
863 | /* can't go backwards */ | |
864 | if (iter->idx > i) | |
865 | return NULL; | |
866 | ||
867 | if (iter->idx < 0) | |
868 | ent = find_next_entry_inc(iter); | |
869 | else | |
870 | ent = iter; | |
871 | ||
872 | while (ent && iter->idx < i) | |
873 | ent = find_next_entry_inc(iter); | |
874 | ||
875 | iter->pos = *pos; | |
876 | ||
877 | if (last_ent && !ent) | |
878 | seq_puts(m, "\n\nvim:ft=help\n"); | |
879 | ||
880 | return ent; | |
881 | } | |
882 | ||
883 | static void *s_start(struct seq_file *m, loff_t *pos) | |
884 | { | |
885 | struct trace_iterator *iter = m->private; | |
886 | void *p = NULL; | |
887 | loff_t l = 0; | |
888 | int i; | |
889 | ||
890 | mutex_lock(&trace_types_lock); | |
891 | ||
892 | if (!current_trace || current_trace != iter->trace) | |
893 | return NULL; | |
894 | ||
895 | atomic_inc(&trace_record_cmdline_disabled); | |
896 | ||
897 | /* let the tracer grab locks here if needed */ | |
898 | if (current_trace->start) | |
899 | current_trace->start(iter); | |
900 | ||
901 | if (*pos != iter->pos) { | |
902 | iter->ent = NULL; | |
903 | iter->cpu = 0; | |
904 | iter->idx = -1; | |
4e3c3333 IM |
905 | iter->prev_ent = NULL; |
906 | iter->prev_cpu = -1; | |
bc0c38d1 | 907 | |
4c11d7ae | 908 | for_each_possible_cpu(i) { |
bc0c38d1 | 909 | iter->next_idx[i] = 0; |
4c11d7ae SR |
910 | iter->next_page[i] = NULL; |
911 | } | |
bc0c38d1 SR |
912 | |
913 | for (p = iter; p && l < *pos; p = s_next(m, p, &l)) | |
914 | ; | |
915 | ||
916 | } else { | |
4c11d7ae | 917 | l = *pos - 1; |
bc0c38d1 SR |
918 | p = s_next(m, p, &l); |
919 | } | |
920 | ||
921 | return p; | |
922 | } | |
923 | ||
924 | static void s_stop(struct seq_file *m, void *p) | |
925 | { | |
926 | struct trace_iterator *iter = m->private; | |
927 | ||
928 | atomic_dec(&trace_record_cmdline_disabled); | |
929 | ||
930 | /* let the tracer release locks here if needed */ | |
931 | if (current_trace && current_trace == iter->trace && iter->trace->stop) | |
932 | iter->trace->stop(iter); | |
933 | ||
934 | mutex_unlock(&trace_types_lock); | |
935 | } | |
936 | ||
b3806b43 | 937 | static int |
214023c3 | 938 | seq_print_sym_short(struct trace_seq *s, const char *fmt, unsigned long address) |
bc0c38d1 SR |
939 | { |
940 | #ifdef CONFIG_KALLSYMS | |
941 | char str[KSYM_SYMBOL_LEN]; | |
942 | ||
943 | kallsyms_lookup(address, NULL, NULL, NULL, str); | |
944 | ||
b3806b43 | 945 | return trace_seq_printf(s, fmt, str); |
bc0c38d1 | 946 | #endif |
b3806b43 | 947 | return 1; |
bc0c38d1 SR |
948 | } |
949 | ||
b3806b43 | 950 | static int |
214023c3 SR |
951 | seq_print_sym_offset(struct trace_seq *s, const char *fmt, |
952 | unsigned long address) | |
bc0c38d1 SR |
953 | { |
954 | #ifdef CONFIG_KALLSYMS | |
955 | char str[KSYM_SYMBOL_LEN]; | |
956 | ||
957 | sprint_symbol(str, address); | |
b3806b43 | 958 | return trace_seq_printf(s, fmt, str); |
bc0c38d1 | 959 | #endif |
b3806b43 | 960 | return 1; |
bc0c38d1 SR |
961 | } |
962 | ||
963 | #ifndef CONFIG_64BIT | |
964 | # define IP_FMT "%08lx" | |
965 | #else | |
966 | # define IP_FMT "%016lx" | |
967 | #endif | |
968 | ||
b3806b43 | 969 | static notrace int |
214023c3 | 970 | seq_print_ip_sym(struct trace_seq *s, unsigned long ip, unsigned long sym_flags) |
bc0c38d1 | 971 | { |
b3806b43 SR |
972 | int ret; |
973 | ||
974 | if (!ip) | |
975 | return trace_seq_printf(s, "0"); | |
bc0c38d1 SR |
976 | |
977 | if (sym_flags & TRACE_ITER_SYM_OFFSET) | |
b3806b43 | 978 | ret = seq_print_sym_offset(s, "%s", ip); |
bc0c38d1 | 979 | else |
b3806b43 SR |
980 | ret = seq_print_sym_short(s, "%s", ip); |
981 | ||
982 | if (!ret) | |
983 | return 0; | |
bc0c38d1 SR |
984 | |
985 | if (sym_flags & TRACE_ITER_SYM_ADDR) | |
b3806b43 SR |
986 | ret = trace_seq_printf(s, " <" IP_FMT ">", ip); |
987 | return ret; | |
bc0c38d1 SR |
988 | } |
989 | ||
4e3c3333 | 990 | static notrace void print_lat_help_header(struct seq_file *m) |
bc0c38d1 SR |
991 | { |
992 | seq_puts(m, "# _------=> CPU# \n"); | |
993 | seq_puts(m, "# / _-----=> irqs-off \n"); | |
994 | seq_puts(m, "# | / _----=> need-resched \n"); | |
995 | seq_puts(m, "# || / _---=> hardirq/softirq \n"); | |
996 | seq_puts(m, "# ||| / _--=> preempt-depth \n"); | |
997 | seq_puts(m, "# |||| / \n"); | |
998 | seq_puts(m, "# ||||| delay \n"); | |
999 | seq_puts(m, "# cmd pid ||||| time | caller \n"); | |
1000 | seq_puts(m, "# \\ / ||||| \\ | / \n"); | |
1001 | } | |
1002 | ||
4e3c3333 | 1003 | static notrace void print_func_help_header(struct seq_file *m) |
bc0c38d1 SR |
1004 | { |
1005 | seq_puts(m, "# TASK-PID CPU# TIMESTAMP FUNCTION\n"); | |
1006 | seq_puts(m, "# | | | | |\n"); | |
1007 | } | |
1008 | ||
1009 | ||
4e3c3333 | 1010 | static notrace void |
bc0c38d1 SR |
1011 | print_trace_header(struct seq_file *m, struct trace_iterator *iter) |
1012 | { | |
1013 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); | |
1014 | struct trace_array *tr = iter->tr; | |
1015 | struct trace_array_cpu *data = tr->data[tr->cpu]; | |
1016 | struct tracer *type = current_trace; | |
4c11d7ae SR |
1017 | unsigned long total = 0; |
1018 | unsigned long entries = 0; | |
bc0c38d1 SR |
1019 | int cpu; |
1020 | const char *name = "preemption"; | |
1021 | ||
1022 | if (type) | |
1023 | name = type->name; | |
1024 | ||
1025 | for_each_possible_cpu(cpu) { | |
c7aafc54 | 1026 | if (head_page(tr->data[cpu])) { |
4c11d7ae SR |
1027 | total += tr->data[cpu]->trace_idx; |
1028 | if (tr->data[cpu]->trace_idx > tr->entries) | |
bc0c38d1 | 1029 | entries += tr->entries; |
4c11d7ae | 1030 | else |
bc0c38d1 SR |
1031 | entries += tr->data[cpu]->trace_idx; |
1032 | } | |
1033 | } | |
1034 | ||
1035 | seq_printf(m, "%s latency trace v1.1.5 on %s\n", | |
1036 | name, UTS_RELEASE); | |
1037 | seq_puts(m, "-----------------------------------" | |
1038 | "---------------------------------\n"); | |
1039 | seq_printf(m, " latency: %lu us, #%lu/%lu, CPU#%d |" | |
1040 | " (M:%s VP:%d, KP:%d, SP:%d HP:%d", | |
57f50be1 | 1041 | nsecs_to_usecs(data->saved_latency), |
bc0c38d1 | 1042 | entries, |
4c11d7ae | 1043 | total, |
bc0c38d1 SR |
1044 | tr->cpu, |
1045 | #if defined(CONFIG_PREEMPT_NONE) | |
1046 | "server", | |
1047 | #elif defined(CONFIG_PREEMPT_VOLUNTARY) | |
1048 | "desktop", | |
1049 | #elif defined(CONFIG_PREEMPT_DESKTOP) | |
1050 | "preempt", | |
1051 | #else | |
1052 | "unknown", | |
1053 | #endif | |
1054 | /* These are reserved for later use */ | |
1055 | 0, 0, 0, 0); | |
1056 | #ifdef CONFIG_SMP | |
1057 | seq_printf(m, " #P:%d)\n", num_online_cpus()); | |
1058 | #else | |
1059 | seq_puts(m, ")\n"); | |
1060 | #endif | |
1061 | seq_puts(m, " -----------------\n"); | |
1062 | seq_printf(m, " | task: %.16s-%d " | |
1063 | "(uid:%d nice:%ld policy:%ld rt_prio:%ld)\n", | |
1064 | data->comm, data->pid, data->uid, data->nice, | |
1065 | data->policy, data->rt_priority); | |
1066 | seq_puts(m, " -----------------\n"); | |
1067 | ||
1068 | if (data->critical_start) { | |
1069 | seq_puts(m, " => started at: "); | |
214023c3 SR |
1070 | seq_print_ip_sym(&iter->seq, data->critical_start, sym_flags); |
1071 | trace_print_seq(m, &iter->seq); | |
bc0c38d1 | 1072 | seq_puts(m, "\n => ended at: "); |
214023c3 SR |
1073 | seq_print_ip_sym(&iter->seq, data->critical_end, sym_flags); |
1074 | trace_print_seq(m, &iter->seq); | |
bc0c38d1 SR |
1075 | seq_puts(m, "\n"); |
1076 | } | |
1077 | ||
1078 | seq_puts(m, "\n"); | |
1079 | } | |
1080 | ||
4e3c3333 | 1081 | static notrace void |
214023c3 | 1082 | lat_print_generic(struct trace_seq *s, struct trace_entry *entry, int cpu) |
bc0c38d1 SR |
1083 | { |
1084 | int hardirq, softirq; | |
1085 | char *comm; | |
1086 | ||
1087 | comm = trace_find_cmdline(entry->pid); | |
1088 | ||
214023c3 SR |
1089 | trace_seq_printf(s, "%8.8s-%-5d ", comm, entry->pid); |
1090 | trace_seq_printf(s, "%d", cpu); | |
1091 | trace_seq_printf(s, "%c%c", | |
1092 | (entry->flags & TRACE_FLAG_IRQS_OFF) ? 'd' : '.', | |
1093 | ((entry->flags & TRACE_FLAG_NEED_RESCHED) ? 'N' : '.')); | |
bc0c38d1 SR |
1094 | |
1095 | hardirq = entry->flags & TRACE_FLAG_HARDIRQ; | |
1096 | softirq = entry->flags & TRACE_FLAG_SOFTIRQ; | |
1097 | if (hardirq && softirq) | |
214023c3 | 1098 | trace_seq_putc(s, 'H'); |
bc0c38d1 SR |
1099 | else { |
1100 | if (hardirq) | |
214023c3 | 1101 | trace_seq_putc(s, 'h'); |
bc0c38d1 SR |
1102 | else { |
1103 | if (softirq) | |
214023c3 | 1104 | trace_seq_putc(s, 's'); |
bc0c38d1 | 1105 | else |
214023c3 | 1106 | trace_seq_putc(s, '.'); |
bc0c38d1 SR |
1107 | } |
1108 | } | |
1109 | ||
1110 | if (entry->preempt_count) | |
214023c3 | 1111 | trace_seq_printf(s, "%x", entry->preempt_count); |
bc0c38d1 | 1112 | else |
214023c3 | 1113 | trace_seq_puts(s, "."); |
bc0c38d1 SR |
1114 | } |
1115 | ||
1116 | unsigned long preempt_mark_thresh = 100; | |
1117 | ||
4e3c3333 | 1118 | static notrace void |
214023c3 | 1119 | lat_print_timestamp(struct trace_seq *s, unsigned long long abs_usecs, |
bc0c38d1 SR |
1120 | unsigned long rel_usecs) |
1121 | { | |
214023c3 | 1122 | trace_seq_printf(s, " %4lldus", abs_usecs); |
bc0c38d1 | 1123 | if (rel_usecs > preempt_mark_thresh) |
214023c3 | 1124 | trace_seq_puts(s, "!: "); |
bc0c38d1 | 1125 | else if (rel_usecs > 1) |
214023c3 | 1126 | trace_seq_puts(s, "+: "); |
bc0c38d1 | 1127 | else |
214023c3 | 1128 | trace_seq_puts(s, " : "); |
bc0c38d1 SR |
1129 | } |
1130 | ||
1131 | static const char state_to_char[] = TASK_STATE_TO_CHAR_STR; | |
1132 | ||
f9896bf3 | 1133 | static notrace int |
214023c3 | 1134 | print_lat_fmt(struct trace_iterator *iter, unsigned int trace_idx, int cpu) |
bc0c38d1 | 1135 | { |
214023c3 | 1136 | struct trace_seq *s = &iter->seq; |
bc0c38d1 SR |
1137 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); |
1138 | struct trace_entry *next_entry = find_next_entry(iter, NULL); | |
1139 | unsigned long verbose = (trace_flags & TRACE_ITER_VERBOSE); | |
1140 | struct trace_entry *entry = iter->ent; | |
1141 | unsigned long abs_usecs; | |
1142 | unsigned long rel_usecs; | |
1143 | char *comm; | |
1144 | int S; | |
1145 | ||
1146 | if (!next_entry) | |
1147 | next_entry = entry; | |
1148 | rel_usecs = ns2usecs(next_entry->t - entry->t); | |
1149 | abs_usecs = ns2usecs(entry->t - iter->tr->time_start); | |
1150 | ||
1151 | if (verbose) { | |
1152 | comm = trace_find_cmdline(entry->pid); | |
214023c3 SR |
1153 | trace_seq_printf(s, "%16s %5d %d %d %08x %08x [%08lx]" |
1154 | " %ld.%03ldms (+%ld.%03ldms): ", | |
1155 | comm, | |
1156 | entry->pid, cpu, entry->flags, | |
1157 | entry->preempt_count, trace_idx, | |
1158 | ns2usecs(entry->t), | |
1159 | abs_usecs/1000, | |
1160 | abs_usecs % 1000, rel_usecs/1000, | |
1161 | rel_usecs % 1000); | |
bc0c38d1 | 1162 | } else { |
214023c3 SR |
1163 | lat_print_generic(s, entry, cpu); |
1164 | lat_print_timestamp(s, abs_usecs, rel_usecs); | |
bc0c38d1 SR |
1165 | } |
1166 | switch (entry->type) { | |
1167 | case TRACE_FN: | |
214023c3 SR |
1168 | seq_print_ip_sym(s, entry->fn.ip, sym_flags); |
1169 | trace_seq_puts(s, " ("); | |
1170 | seq_print_ip_sym(s, entry->fn.parent_ip, sym_flags); | |
1171 | trace_seq_puts(s, ")\n"); | |
bc0c38d1 SR |
1172 | break; |
1173 | case TRACE_CTX: | |
1174 | S = entry->ctx.prev_state < sizeof(state_to_char) ? | |
1175 | state_to_char[entry->ctx.prev_state] : 'X'; | |
1176 | comm = trace_find_cmdline(entry->ctx.next_pid); | |
214023c3 SR |
1177 | trace_seq_printf(s, " %d:%d:%c --> %d:%d %s\n", |
1178 | entry->ctx.prev_pid, | |
1179 | entry->ctx.prev_prio, | |
1180 | S, | |
1181 | entry->ctx.next_pid, | |
1182 | entry->ctx.next_prio, | |
1183 | comm); | |
bc0c38d1 | 1184 | break; |
f0a920d5 IM |
1185 | case TRACE_SPECIAL: |
1186 | trace_seq_printf(s, " %lx %lx %lx\n", | |
1187 | entry->special.arg1, | |
1188 | entry->special.arg2, | |
1189 | entry->special.arg3); | |
1190 | break; | |
89b2f978 | 1191 | default: |
214023c3 | 1192 | trace_seq_printf(s, "Unknown type %d\n", entry->type); |
bc0c38d1 | 1193 | } |
f9896bf3 | 1194 | return 1; |
bc0c38d1 SR |
1195 | } |
1196 | ||
f9896bf3 | 1197 | static notrace int print_trace_fmt(struct trace_iterator *iter) |
bc0c38d1 | 1198 | { |
214023c3 | 1199 | struct trace_seq *s = &iter->seq; |
bc0c38d1 | 1200 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); |
4e3c3333 | 1201 | struct trace_entry *entry; |
bc0c38d1 SR |
1202 | unsigned long usec_rem; |
1203 | unsigned long long t; | |
1204 | unsigned long secs; | |
1205 | char *comm; | |
1206 | int S; | |
b3806b43 | 1207 | int ret; |
bc0c38d1 | 1208 | |
4e3c3333 IM |
1209 | entry = iter->ent; |
1210 | ||
bc0c38d1 SR |
1211 | comm = trace_find_cmdline(iter->ent->pid); |
1212 | ||
cdd31cd2 | 1213 | t = ns2usecs(entry->t); |
bc0c38d1 SR |
1214 | usec_rem = do_div(t, 1000000ULL); |
1215 | secs = (unsigned long)t; | |
1216 | ||
b3806b43 SR |
1217 | ret = trace_seq_printf(s, "%16s-%-5d ", comm, entry->pid); |
1218 | if (!ret) | |
1219 | return 0; | |
1220 | ret = trace_seq_printf(s, "[%02d] ", iter->cpu); | |
1221 | if (!ret) | |
1222 | return 0; | |
1223 | ret = trace_seq_printf(s, "%5lu.%06lu: ", secs, usec_rem); | |
1224 | if (!ret) | |
1225 | return 0; | |
bc0c38d1 SR |
1226 | |
1227 | switch (entry->type) { | |
1228 | case TRACE_FN: | |
b3806b43 SR |
1229 | ret = seq_print_ip_sym(s, entry->fn.ip, sym_flags); |
1230 | if (!ret) | |
1231 | return 0; | |
bc0c38d1 SR |
1232 | if ((sym_flags & TRACE_ITER_PRINT_PARENT) && |
1233 | entry->fn.parent_ip) { | |
b3806b43 SR |
1234 | ret = trace_seq_printf(s, " <-"); |
1235 | if (!ret) | |
1236 | return 0; | |
1237 | ret = seq_print_ip_sym(s, entry->fn.parent_ip, | |
1238 | sym_flags); | |
1239 | if (!ret) | |
1240 | return 0; | |
bc0c38d1 | 1241 | } |
b3806b43 SR |
1242 | ret = trace_seq_printf(s, "\n"); |
1243 | if (!ret) | |
1244 | return 0; | |
bc0c38d1 SR |
1245 | break; |
1246 | case TRACE_CTX: | |
1247 | S = entry->ctx.prev_state < sizeof(state_to_char) ? | |
1248 | state_to_char[entry->ctx.prev_state] : 'X'; | |
b3806b43 SR |
1249 | ret = trace_seq_printf(s, " %d:%d:%c ==> %d:%d\n", |
1250 | entry->ctx.prev_pid, | |
1251 | entry->ctx.prev_prio, | |
1252 | S, | |
1253 | entry->ctx.next_pid, | |
1254 | entry->ctx.next_prio); | |
1255 | if (!ret) | |
1256 | return 0; | |
bc0c38d1 | 1257 | break; |
f0a920d5 IM |
1258 | case TRACE_SPECIAL: |
1259 | ret = trace_seq_printf(s, " %lx %lx %lx\n", | |
1260 | entry->special.arg1, | |
1261 | entry->special.arg2, | |
1262 | entry->special.arg3); | |
1263 | if (!ret) | |
1264 | return 0; | |
1265 | break; | |
bc0c38d1 | 1266 | } |
b3806b43 | 1267 | return 1; |
bc0c38d1 SR |
1268 | } |
1269 | ||
f9896bf3 IM |
1270 | static notrace int print_raw_fmt(struct trace_iterator *iter) |
1271 | { | |
1272 | struct trace_seq *s = &iter->seq; | |
1273 | struct trace_entry *entry; | |
1274 | int ret; | |
1275 | int S; | |
1276 | ||
1277 | entry = iter->ent; | |
1278 | ||
1279 | ret = trace_seq_printf(s, "%d %d %llu ", | |
1280 | entry->pid, iter->cpu, entry->t); | |
1281 | if (!ret) | |
1282 | return 0; | |
1283 | ||
1284 | switch (entry->type) { | |
1285 | case TRACE_FN: | |
1286 | ret = trace_seq_printf(s, "%x %x\n", | |
1287 | entry->fn.ip, entry->fn.parent_ip); | |
1288 | if (!ret) | |
1289 | return 0; | |
1290 | break; | |
1291 | case TRACE_CTX: | |
1292 | S = entry->ctx.prev_state < sizeof(state_to_char) ? | |
1293 | state_to_char[entry->ctx.prev_state] : 'X'; | |
1294 | ret = trace_seq_printf(s, "%d %d %c %d %d\n", | |
1295 | entry->ctx.prev_pid, | |
1296 | entry->ctx.prev_prio, | |
1297 | S, | |
1298 | entry->ctx.next_pid, | |
1299 | entry->ctx.next_prio); | |
1300 | if (!ret) | |
1301 | return 0; | |
1302 | break; | |
f0a920d5 IM |
1303 | case TRACE_SPECIAL: |
1304 | ret = trace_seq_printf(s, " %lx %lx %lx\n", | |
1305 | entry->special.arg1, | |
1306 | entry->special.arg2, | |
1307 | entry->special.arg3); | |
1308 | if (!ret) | |
1309 | return 0; | |
1310 | break; | |
f9896bf3 IM |
1311 | } |
1312 | return 1; | |
1313 | } | |
1314 | ||
cb0f12aa IM |
1315 | #define SEQ_PUT_FIELD_RET(s, x) \ |
1316 | do { \ | |
1317 | if (!trace_seq_putmem(s, &(x), sizeof(x))) \ | |
1318 | return 0; \ | |
1319 | } while (0) | |
1320 | ||
1321 | static notrace int print_bin_fmt(struct trace_iterator *iter) | |
1322 | { | |
1323 | struct trace_seq *s = &iter->seq; | |
1324 | struct trace_entry *entry; | |
1325 | ||
1326 | entry = iter->ent; | |
1327 | ||
1328 | SEQ_PUT_FIELD_RET(s, entry->pid); | |
1329 | SEQ_PUT_FIELD_RET(s, entry->cpu); | |
1330 | SEQ_PUT_FIELD_RET(s, entry->t); | |
1331 | ||
1332 | switch (entry->type) { | |
1333 | case TRACE_FN: | |
1334 | SEQ_PUT_FIELD_RET(s, entry->fn.ip); | |
1335 | SEQ_PUT_FIELD_RET(s, entry->fn.parent_ip); | |
1336 | break; | |
1337 | case TRACE_CTX: | |
1338 | SEQ_PUT_FIELD_RET(s, entry->ctx.prev_pid); | |
1339 | SEQ_PUT_FIELD_RET(s, entry->ctx.prev_prio); | |
1340 | SEQ_PUT_FIELD_RET(s, entry->ctx.prev_state); | |
1341 | SEQ_PUT_FIELD_RET(s, entry->ctx.next_pid); | |
1342 | SEQ_PUT_FIELD_RET(s, entry->ctx.next_prio); | |
1343 | break; | |
f0a920d5 IM |
1344 | case TRACE_SPECIAL: |
1345 | SEQ_PUT_FIELD_RET(s, entry->special.arg1); | |
1346 | SEQ_PUT_FIELD_RET(s, entry->special.arg2); | |
1347 | SEQ_PUT_FIELD_RET(s, entry->special.arg3); | |
1348 | break; | |
cb0f12aa IM |
1349 | } |
1350 | return 1; | |
1351 | } | |
1352 | ||
bc0c38d1 SR |
1353 | static int trace_empty(struct trace_iterator *iter) |
1354 | { | |
1355 | struct trace_array_cpu *data; | |
1356 | int cpu; | |
1357 | ||
1358 | for_each_possible_cpu(cpu) { | |
1359 | data = iter->tr->data[cpu]; | |
1360 | ||
b3806b43 SR |
1361 | if (head_page(data) && data->trace_idx && |
1362 | (data->trace_tail != data->trace_head || | |
1363 | data->trace_tail_idx != data->trace_head_idx)) | |
bc0c38d1 SR |
1364 | return 0; |
1365 | } | |
1366 | return 1; | |
1367 | } | |
1368 | ||
f9896bf3 IM |
1369 | static int print_trace_line(struct trace_iterator *iter) |
1370 | { | |
cb0f12aa IM |
1371 | if (trace_flags & TRACE_ITER_BIN) |
1372 | return print_bin_fmt(iter); | |
1373 | ||
f9896bf3 IM |
1374 | if (trace_flags & TRACE_ITER_RAW) |
1375 | return print_raw_fmt(iter); | |
1376 | ||
1377 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) | |
1378 | return print_lat_fmt(iter, iter->idx, iter->cpu); | |
1379 | ||
1380 | return print_trace_fmt(iter); | |
1381 | } | |
1382 | ||
bc0c38d1 SR |
1383 | static int s_show(struct seq_file *m, void *v) |
1384 | { | |
1385 | struct trace_iterator *iter = v; | |
1386 | ||
1387 | if (iter->ent == NULL) { | |
1388 | if (iter->tr) { | |
1389 | seq_printf(m, "# tracer: %s\n", iter->trace->name); | |
1390 | seq_puts(m, "#\n"); | |
1391 | } | |
1392 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) { | |
1393 | /* print nothing if the buffers are empty */ | |
1394 | if (trace_empty(iter)) | |
1395 | return 0; | |
1396 | print_trace_header(m, iter); | |
1397 | if (!(trace_flags & TRACE_ITER_VERBOSE)) | |
1398 | print_lat_help_header(m); | |
1399 | } else { | |
1400 | if (!(trace_flags & TRACE_ITER_VERBOSE)) | |
1401 | print_func_help_header(m); | |
1402 | } | |
1403 | } else { | |
f9896bf3 | 1404 | print_trace_line(iter); |
214023c3 | 1405 | trace_print_seq(m, &iter->seq); |
bc0c38d1 SR |
1406 | } |
1407 | ||
1408 | return 0; | |
1409 | } | |
1410 | ||
1411 | static struct seq_operations tracer_seq_ops = { | |
4bf39a94 IM |
1412 | .start = s_start, |
1413 | .next = s_next, | |
1414 | .stop = s_stop, | |
1415 | .show = s_show, | |
bc0c38d1 SR |
1416 | }; |
1417 | ||
1418 | static struct trace_iterator notrace * | |
1419 | __tracing_open(struct inode *inode, struct file *file, int *ret) | |
1420 | { | |
1421 | struct trace_iterator *iter; | |
1422 | ||
60a11774 SR |
1423 | if (tracing_disabled) { |
1424 | *ret = -ENODEV; | |
1425 | return NULL; | |
1426 | } | |
1427 | ||
bc0c38d1 SR |
1428 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); |
1429 | if (!iter) { | |
1430 | *ret = -ENOMEM; | |
1431 | goto out; | |
1432 | } | |
1433 | ||
1434 | mutex_lock(&trace_types_lock); | |
1435 | if (current_trace && current_trace->print_max) | |
1436 | iter->tr = &max_tr; | |
1437 | else | |
1438 | iter->tr = inode->i_private; | |
1439 | iter->trace = current_trace; | |
1440 | iter->pos = -1; | |
1441 | ||
1442 | /* TODO stop tracer */ | |
1443 | *ret = seq_open(file, &tracer_seq_ops); | |
1444 | if (!*ret) { | |
1445 | struct seq_file *m = file->private_data; | |
1446 | m->private = iter; | |
1447 | ||
1448 | /* stop the trace while dumping */ | |
1449 | if (iter->tr->ctrl) | |
1450 | tracer_enabled = 0; | |
1451 | ||
1452 | if (iter->trace && iter->trace->open) | |
1453 | iter->trace->open(iter); | |
1454 | } else { | |
1455 | kfree(iter); | |
1456 | iter = NULL; | |
1457 | } | |
1458 | mutex_unlock(&trace_types_lock); | |
1459 | ||
1460 | out: | |
1461 | return iter; | |
1462 | } | |
1463 | ||
1464 | int tracing_open_generic(struct inode *inode, struct file *filp) | |
1465 | { | |
60a11774 SR |
1466 | if (tracing_disabled) |
1467 | return -ENODEV; | |
1468 | ||
bc0c38d1 SR |
1469 | filp->private_data = inode->i_private; |
1470 | return 0; | |
1471 | } | |
1472 | ||
1473 | int tracing_release(struct inode *inode, struct file *file) | |
1474 | { | |
1475 | struct seq_file *m = (struct seq_file *)file->private_data; | |
1476 | struct trace_iterator *iter = m->private; | |
1477 | ||
1478 | mutex_lock(&trace_types_lock); | |
1479 | if (iter->trace && iter->trace->close) | |
1480 | iter->trace->close(iter); | |
1481 | ||
1482 | /* reenable tracing if it was previously enabled */ | |
1483 | if (iter->tr->ctrl) | |
1484 | tracer_enabled = 1; | |
1485 | mutex_unlock(&trace_types_lock); | |
1486 | ||
1487 | seq_release(inode, file); | |
1488 | kfree(iter); | |
1489 | return 0; | |
1490 | } | |
1491 | ||
1492 | static int tracing_open(struct inode *inode, struct file *file) | |
1493 | { | |
1494 | int ret; | |
1495 | ||
1496 | __tracing_open(inode, file, &ret); | |
1497 | ||
1498 | return ret; | |
1499 | } | |
1500 | ||
1501 | static int tracing_lt_open(struct inode *inode, struct file *file) | |
1502 | { | |
1503 | struct trace_iterator *iter; | |
1504 | int ret; | |
1505 | ||
1506 | iter = __tracing_open(inode, file, &ret); | |
1507 | ||
1508 | if (!ret) | |
1509 | iter->iter_flags |= TRACE_FILE_LAT_FMT; | |
1510 | ||
1511 | return ret; | |
1512 | } | |
1513 | ||
1514 | ||
4e3c3333 | 1515 | static notrace void * |
bc0c38d1 SR |
1516 | t_next(struct seq_file *m, void *v, loff_t *pos) |
1517 | { | |
1518 | struct tracer *t = m->private; | |
1519 | ||
1520 | (*pos)++; | |
1521 | ||
1522 | if (t) | |
1523 | t = t->next; | |
1524 | ||
1525 | m->private = t; | |
1526 | ||
1527 | return t; | |
1528 | } | |
1529 | ||
1530 | static void *t_start(struct seq_file *m, loff_t *pos) | |
1531 | { | |
1532 | struct tracer *t = m->private; | |
1533 | loff_t l = 0; | |
1534 | ||
1535 | mutex_lock(&trace_types_lock); | |
1536 | for (; t && l < *pos; t = t_next(m, t, &l)) | |
1537 | ; | |
1538 | ||
1539 | return t; | |
1540 | } | |
1541 | ||
1542 | static void t_stop(struct seq_file *m, void *p) | |
1543 | { | |
1544 | mutex_unlock(&trace_types_lock); | |
1545 | } | |
1546 | ||
1547 | static int t_show(struct seq_file *m, void *v) | |
1548 | { | |
1549 | struct tracer *t = v; | |
1550 | ||
1551 | if (!t) | |
1552 | return 0; | |
1553 | ||
1554 | seq_printf(m, "%s", t->name); | |
1555 | if (t->next) | |
1556 | seq_putc(m, ' '); | |
1557 | else | |
1558 | seq_putc(m, '\n'); | |
1559 | ||
1560 | return 0; | |
1561 | } | |
1562 | ||
1563 | static struct seq_operations show_traces_seq_ops = { | |
4bf39a94 IM |
1564 | .start = t_start, |
1565 | .next = t_next, | |
1566 | .stop = t_stop, | |
1567 | .show = t_show, | |
bc0c38d1 SR |
1568 | }; |
1569 | ||
1570 | static int show_traces_open(struct inode *inode, struct file *file) | |
1571 | { | |
1572 | int ret; | |
1573 | ||
60a11774 SR |
1574 | if (tracing_disabled) |
1575 | return -ENODEV; | |
1576 | ||
bc0c38d1 SR |
1577 | ret = seq_open(file, &show_traces_seq_ops); |
1578 | if (!ret) { | |
1579 | struct seq_file *m = file->private_data; | |
1580 | m->private = trace_types; | |
1581 | } | |
1582 | ||
1583 | return ret; | |
1584 | } | |
1585 | ||
1586 | static struct file_operations tracing_fops = { | |
4bf39a94 IM |
1587 | .open = tracing_open, |
1588 | .read = seq_read, | |
1589 | .llseek = seq_lseek, | |
1590 | .release = tracing_release, | |
bc0c38d1 SR |
1591 | }; |
1592 | ||
1593 | static struct file_operations tracing_lt_fops = { | |
4bf39a94 IM |
1594 | .open = tracing_lt_open, |
1595 | .read = seq_read, | |
1596 | .llseek = seq_lseek, | |
1597 | .release = tracing_release, | |
bc0c38d1 SR |
1598 | }; |
1599 | ||
1600 | static struct file_operations show_traces_fops = { | |
1601 | .open = show_traces_open, | |
1602 | .read = seq_read, | |
1603 | .release = seq_release, | |
1604 | }; | |
1605 | ||
1606 | static ssize_t | |
1607 | tracing_iter_ctrl_read(struct file *filp, char __user *ubuf, | |
1608 | size_t cnt, loff_t *ppos) | |
1609 | { | |
1610 | char *buf; | |
1611 | int r = 0; | |
1612 | int len = 0; | |
1613 | int i; | |
1614 | ||
1615 | /* calulate max size */ | |
1616 | for (i = 0; trace_options[i]; i++) { | |
1617 | len += strlen(trace_options[i]); | |
1618 | len += 3; /* "no" and space */ | |
1619 | } | |
1620 | ||
1621 | /* +2 for \n and \0 */ | |
1622 | buf = kmalloc(len + 2, GFP_KERNEL); | |
1623 | if (!buf) | |
1624 | return -ENOMEM; | |
1625 | ||
1626 | for (i = 0; trace_options[i]; i++) { | |
1627 | if (trace_flags & (1 << i)) | |
1628 | r += sprintf(buf + r, "%s ", trace_options[i]); | |
1629 | else | |
1630 | r += sprintf(buf + r, "no%s ", trace_options[i]); | |
1631 | } | |
1632 | ||
1633 | r += sprintf(buf + r, "\n"); | |
1634 | WARN_ON(r >= len + 2); | |
1635 | ||
1636 | r = simple_read_from_buffer(ubuf, cnt, ppos, | |
1637 | buf, r); | |
1638 | ||
1639 | kfree(buf); | |
1640 | ||
1641 | return r; | |
1642 | } | |
1643 | ||
1644 | static ssize_t | |
1645 | tracing_iter_ctrl_write(struct file *filp, const char __user *ubuf, | |
1646 | size_t cnt, loff_t *ppos) | |
1647 | { | |
1648 | char buf[64]; | |
1649 | char *cmp = buf; | |
1650 | int neg = 0; | |
1651 | int i; | |
1652 | ||
1653 | if (cnt > 63) | |
1654 | cnt = 63; | |
1655 | ||
1656 | if (copy_from_user(&buf, ubuf, cnt)) | |
1657 | return -EFAULT; | |
1658 | ||
1659 | buf[cnt] = 0; | |
1660 | ||
1661 | if (strncmp(buf, "no", 2) == 0) { | |
1662 | neg = 1; | |
1663 | cmp += 2; | |
1664 | } | |
1665 | ||
1666 | for (i = 0; trace_options[i]; i++) { | |
1667 | int len = strlen(trace_options[i]); | |
1668 | ||
1669 | if (strncmp(cmp, trace_options[i], len) == 0) { | |
1670 | if (neg) | |
1671 | trace_flags &= ~(1 << i); | |
1672 | else | |
1673 | trace_flags |= (1 << i); | |
1674 | break; | |
1675 | } | |
1676 | } | |
1677 | ||
1678 | filp->f_pos += cnt; | |
1679 | ||
1680 | return cnt; | |
1681 | } | |
1682 | ||
1683 | static struct file_operations tracing_iter_fops = { | |
1684 | .open = tracing_open_generic, | |
1685 | .read = tracing_iter_ctrl_read, | |
1686 | .write = tracing_iter_ctrl_write, | |
1687 | }; | |
1688 | ||
7bd2f24c IM |
1689 | static const char readme_msg[] = |
1690 | "tracing mini-HOWTO:\n\n" | |
1691 | "# mkdir /debug\n" | |
1692 | "# mount -t debugfs nodev /debug\n\n" | |
1693 | "# cat /debug/tracing/available_tracers\n" | |
1694 | "wakeup preemptirqsoff preemptoff irqsoff ftrace sched_switch none\n\n" | |
1695 | "# cat /debug/tracing/current_tracer\n" | |
1696 | "none\n" | |
1697 | "# echo sched_switch > /debug/tracing/current_tracer\n" | |
1698 | "# cat /debug/tracing/current_tracer\n" | |
1699 | "sched_switch\n" | |
1700 | "# cat /debug/tracing/iter_ctrl\n" | |
1701 | "noprint-parent nosym-offset nosym-addr noverbose\n" | |
1702 | "# echo print-parent > /debug/tracing/iter_ctrl\n" | |
1703 | "# echo 1 > /debug/tracing/tracing_enabled\n" | |
1704 | "# cat /debug/tracing/trace > /tmp/trace.txt\n" | |
1705 | "echo 0 > /debug/tracing/tracing_enabled\n" | |
1706 | ; | |
1707 | ||
1708 | static ssize_t | |
1709 | tracing_readme_read(struct file *filp, char __user *ubuf, | |
1710 | size_t cnt, loff_t *ppos) | |
1711 | { | |
1712 | return simple_read_from_buffer(ubuf, cnt, ppos, | |
1713 | readme_msg, strlen(readme_msg)); | |
1714 | } | |
1715 | ||
1716 | static struct file_operations tracing_readme_fops = { | |
1717 | .open = tracing_open_generic, | |
1718 | .read = tracing_readme_read, | |
1719 | }; | |
1720 | ||
1721 | ||
bc0c38d1 SR |
1722 | static ssize_t |
1723 | tracing_ctrl_read(struct file *filp, char __user *ubuf, | |
1724 | size_t cnt, loff_t *ppos) | |
1725 | { | |
1726 | struct trace_array *tr = filp->private_data; | |
1727 | char buf[64]; | |
1728 | int r; | |
1729 | ||
1730 | r = sprintf(buf, "%ld\n", tr->ctrl); | |
4e3c3333 | 1731 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
1732 | } |
1733 | ||
1734 | static ssize_t | |
1735 | tracing_ctrl_write(struct file *filp, const char __user *ubuf, | |
1736 | size_t cnt, loff_t *ppos) | |
1737 | { | |
1738 | struct trace_array *tr = filp->private_data; | |
1739 | long val; | |
1740 | char buf[64]; | |
1741 | ||
1742 | if (cnt > 63) | |
1743 | cnt = 63; | |
1744 | ||
1745 | if (copy_from_user(&buf, ubuf, cnt)) | |
1746 | return -EFAULT; | |
1747 | ||
1748 | buf[cnt] = 0; | |
1749 | ||
1750 | val = simple_strtoul(buf, NULL, 10); | |
1751 | ||
1752 | val = !!val; | |
1753 | ||
1754 | mutex_lock(&trace_types_lock); | |
1755 | if (tr->ctrl ^ val) { | |
1756 | if (val) | |
1757 | tracer_enabled = 1; | |
1758 | else | |
1759 | tracer_enabled = 0; | |
1760 | ||
1761 | tr->ctrl = val; | |
1762 | ||
1763 | if (current_trace && current_trace->ctrl_update) | |
1764 | current_trace->ctrl_update(tr); | |
1765 | } | |
1766 | mutex_unlock(&trace_types_lock); | |
1767 | ||
1768 | filp->f_pos += cnt; | |
1769 | ||
1770 | return cnt; | |
1771 | } | |
1772 | ||
1773 | static ssize_t | |
1774 | tracing_set_trace_read(struct file *filp, char __user *ubuf, | |
1775 | size_t cnt, loff_t *ppos) | |
1776 | { | |
1777 | char buf[max_tracer_type_len+2]; | |
1778 | int r; | |
1779 | ||
1780 | mutex_lock(&trace_types_lock); | |
1781 | if (current_trace) | |
1782 | r = sprintf(buf, "%s\n", current_trace->name); | |
1783 | else | |
1784 | r = sprintf(buf, "\n"); | |
1785 | mutex_unlock(&trace_types_lock); | |
1786 | ||
4bf39a94 | 1787 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
1788 | } |
1789 | ||
1790 | static ssize_t | |
1791 | tracing_set_trace_write(struct file *filp, const char __user *ubuf, | |
1792 | size_t cnt, loff_t *ppos) | |
1793 | { | |
1794 | struct trace_array *tr = &global_trace; | |
1795 | struct tracer *t; | |
1796 | char buf[max_tracer_type_len+1]; | |
1797 | int i; | |
1798 | ||
1799 | if (cnt > max_tracer_type_len) | |
1800 | cnt = max_tracer_type_len; | |
1801 | ||
1802 | if (copy_from_user(&buf, ubuf, cnt)) | |
1803 | return -EFAULT; | |
1804 | ||
1805 | buf[cnt] = 0; | |
1806 | ||
1807 | /* strip ending whitespace. */ | |
1808 | for (i = cnt - 1; i > 0 && isspace(buf[i]); i--) | |
1809 | buf[i] = 0; | |
1810 | ||
1811 | mutex_lock(&trace_types_lock); | |
1812 | for (t = trace_types; t; t = t->next) { | |
1813 | if (strcmp(t->name, buf) == 0) | |
1814 | break; | |
1815 | } | |
1816 | if (!t || t == current_trace) | |
1817 | goto out; | |
1818 | ||
1819 | if (current_trace && current_trace->reset) | |
1820 | current_trace->reset(tr); | |
1821 | ||
1822 | current_trace = t; | |
1823 | if (t->init) | |
1824 | t->init(tr); | |
1825 | ||
1826 | out: | |
1827 | mutex_unlock(&trace_types_lock); | |
1828 | ||
1829 | filp->f_pos += cnt; | |
1830 | ||
1831 | return cnt; | |
1832 | } | |
1833 | ||
1834 | static ssize_t | |
1835 | tracing_max_lat_read(struct file *filp, char __user *ubuf, | |
1836 | size_t cnt, loff_t *ppos) | |
1837 | { | |
1838 | unsigned long *ptr = filp->private_data; | |
1839 | char buf[64]; | |
1840 | int r; | |
1841 | ||
1842 | r = snprintf(buf, 64, "%ld\n", | |
1843 | *ptr == (unsigned long)-1 ? -1 : nsecs_to_usecs(*ptr)); | |
1844 | if (r > 64) | |
1845 | r = 64; | |
4bf39a94 | 1846 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
1847 | } |
1848 | ||
1849 | static ssize_t | |
1850 | tracing_max_lat_write(struct file *filp, const char __user *ubuf, | |
1851 | size_t cnt, loff_t *ppos) | |
1852 | { | |
1853 | long *ptr = filp->private_data; | |
1854 | long val; | |
1855 | char buf[64]; | |
1856 | ||
1857 | if (cnt > 63) | |
1858 | cnt = 63; | |
1859 | ||
1860 | if (copy_from_user(&buf, ubuf, cnt)) | |
1861 | return -EFAULT; | |
1862 | ||
1863 | buf[cnt] = 0; | |
1864 | ||
1865 | val = simple_strtoul(buf, NULL, 10); | |
1866 | ||
1867 | *ptr = val * 1000; | |
1868 | ||
1869 | return cnt; | |
1870 | } | |
1871 | ||
b3806b43 SR |
1872 | static atomic_t tracing_reader; |
1873 | ||
1874 | static int tracing_open_pipe(struct inode *inode, struct file *filp) | |
1875 | { | |
1876 | struct trace_iterator *iter; | |
1877 | ||
1878 | if (tracing_disabled) | |
1879 | return -ENODEV; | |
1880 | ||
1881 | /* We only allow for reader of the pipe */ | |
1882 | if (atomic_inc_return(&tracing_reader) != 1) { | |
1883 | atomic_dec(&tracing_reader); | |
1884 | return -EBUSY; | |
1885 | } | |
1886 | ||
1887 | /* create a buffer to store the information to pass to userspace */ | |
1888 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); | |
1889 | if (!iter) | |
1890 | return -ENOMEM; | |
1891 | ||
1892 | iter->tr = &global_trace; | |
1893 | ||
1894 | filp->private_data = iter; | |
1895 | ||
1896 | return 0; | |
1897 | } | |
1898 | ||
1899 | static int tracing_release_pipe(struct inode *inode, struct file *file) | |
1900 | { | |
1901 | struct trace_iterator *iter = file->private_data; | |
1902 | ||
1903 | kfree(iter); | |
1904 | atomic_dec(&tracing_reader); | |
1905 | ||
1906 | return 0; | |
1907 | } | |
1908 | ||
1909 | /* | |
1910 | * Consumer reader. | |
1911 | */ | |
1912 | static ssize_t | |
1913 | tracing_read_pipe(struct file *filp, char __user *ubuf, | |
1914 | size_t cnt, loff_t *ppos) | |
1915 | { | |
1916 | struct trace_iterator *iter = filp->private_data; | |
1917 | struct trace_array_cpu *data; | |
1918 | static cpumask_t mask; | |
b3806b43 SR |
1919 | static int start; |
1920 | unsigned long flags; | |
1921 | int read = 0; | |
1922 | int cpu; | |
1923 | int len; | |
1924 | int ret; | |
1925 | ||
1926 | /* return any leftover data */ | |
1927 | if (iter->seq.len > start) { | |
1928 | len = iter->seq.len - start; | |
1929 | if (cnt > len) | |
1930 | cnt = len; | |
1931 | ret = copy_to_user(ubuf, iter->seq.buffer + start, cnt); | |
1932 | if (ret) | |
1933 | cnt = -EFAULT; | |
1934 | ||
1935 | start += len; | |
1936 | ||
1937 | return cnt; | |
1938 | } | |
1939 | ||
1940 | trace_seq_reset(&iter->seq); | |
1941 | start = 0; | |
1942 | ||
1943 | while (trace_empty(iter)) { | |
1944 | /* | |
1945 | * This is a make-shift waitqueue. The reason we don't use | |
1946 | * an actual wait queue is because: | |
1947 | * 1) we only ever have one waiter | |
1948 | * 2) the tracing, traces all functions, we don't want | |
1949 | * the overhead of calling wake_up and friends | |
1950 | * (and tracing them too) | |
1951 | * Anyway, this is really very primitive wakeup. | |
1952 | */ | |
1953 | set_current_state(TASK_INTERRUPTIBLE); | |
1954 | iter->tr->waiter = current; | |
1955 | ||
1956 | /* sleep for one second, and try again. */ | |
1957 | schedule_timeout(HZ); | |
1958 | ||
1959 | iter->tr->waiter = NULL; | |
1960 | ||
1961 | if (signal_pending(current)) | |
1962 | return -EINTR; | |
1963 | ||
1964 | /* | |
1965 | * We block until we read something and tracing is disabled. | |
1966 | * We still block if tracing is disabled, but we have never | |
1967 | * read anything. This allows a user to cat this file, and | |
1968 | * then enable tracing. But after we have read something, | |
1969 | * we give an EOF when tracing is again disabled. | |
1970 | * | |
1971 | * iter->pos will be 0 if we haven't read anything. | |
1972 | */ | |
1973 | if (!tracer_enabled && iter->pos) | |
1974 | break; | |
1975 | ||
1976 | continue; | |
1977 | } | |
1978 | ||
1979 | /* stop when tracing is finished */ | |
1980 | if (trace_empty(iter)) | |
1981 | return 0; | |
1982 | ||
1983 | if (cnt >= PAGE_SIZE) | |
1984 | cnt = PAGE_SIZE - 1; | |
1985 | ||
1986 | memset(iter, 0, sizeof(*iter)); | |
1987 | iter->tr = &global_trace; | |
1988 | iter->pos = -1; | |
1989 | ||
1990 | /* | |
1991 | * We need to stop all tracing on all CPUS to read the | |
1992 | * the next buffer. This is a bit expensive, but is | |
1993 | * not done often. We fill all what we can read, | |
1994 | * and then release the locks again. | |
1995 | */ | |
1996 | ||
1997 | cpus_clear(mask); | |
1998 | local_irq_save(flags); | |
1999 | for_each_possible_cpu(cpu) { | |
2000 | data = iter->tr->data[cpu]; | |
2001 | ||
2002 | if (!head_page(data) || !data->trace_idx) | |
2003 | continue; | |
2004 | ||
2005 | atomic_inc(&data->disabled); | |
2006 | spin_lock(&data->lock); | |
2007 | cpu_set(cpu, mask); | |
2008 | } | |
2009 | ||
088b1e42 SR |
2010 | while (find_next_entry_inc(iter) != NULL) { |
2011 | int len = iter->seq.len; | |
2012 | ||
f9896bf3 | 2013 | ret = print_trace_line(iter); |
088b1e42 SR |
2014 | if (!ret) { |
2015 | /* don't print partial lines */ | |
2016 | iter->seq.len = len; | |
b3806b43 | 2017 | break; |
088b1e42 | 2018 | } |
b3806b43 SR |
2019 | |
2020 | trace_consume(iter); | |
2021 | ||
2022 | if (iter->seq.len >= cnt) | |
2023 | break; | |
b3806b43 SR |
2024 | } |
2025 | ||
d4c5a2f5 | 2026 | for_each_cpu_mask(cpu, mask) { |
b3806b43 | 2027 | data = iter->tr->data[cpu]; |
b3806b43 SR |
2028 | spin_unlock(&data->lock); |
2029 | atomic_dec(&data->disabled); | |
2030 | } | |
2031 | local_irq_restore(flags); | |
2032 | ||
2033 | /* Now copy what we have to the user */ | |
2034 | read = iter->seq.len; | |
2035 | if (read > cnt) | |
2036 | read = cnt; | |
2037 | ||
2038 | ret = copy_to_user(ubuf, iter->seq.buffer, read); | |
2039 | ||
2040 | if (read < iter->seq.len) | |
2041 | start = read; | |
2042 | else | |
2043 | trace_seq_reset(&iter->seq); | |
2044 | ||
2045 | if (ret) | |
2046 | read = -EFAULT; | |
2047 | ||
2048 | return read; | |
2049 | } | |
2050 | ||
bc0c38d1 | 2051 | static struct file_operations tracing_max_lat_fops = { |
4bf39a94 IM |
2052 | .open = tracing_open_generic, |
2053 | .read = tracing_max_lat_read, | |
2054 | .write = tracing_max_lat_write, | |
bc0c38d1 SR |
2055 | }; |
2056 | ||
2057 | static struct file_operations tracing_ctrl_fops = { | |
4bf39a94 IM |
2058 | .open = tracing_open_generic, |
2059 | .read = tracing_ctrl_read, | |
2060 | .write = tracing_ctrl_write, | |
bc0c38d1 SR |
2061 | }; |
2062 | ||
2063 | static struct file_operations set_tracer_fops = { | |
4bf39a94 IM |
2064 | .open = tracing_open_generic, |
2065 | .read = tracing_set_trace_read, | |
2066 | .write = tracing_set_trace_write, | |
bc0c38d1 SR |
2067 | }; |
2068 | ||
b3806b43 | 2069 | static struct file_operations tracing_pipe_fops = { |
4bf39a94 IM |
2070 | .open = tracing_open_pipe, |
2071 | .read = tracing_read_pipe, | |
2072 | .release = tracing_release_pipe, | |
b3806b43 SR |
2073 | }; |
2074 | ||
bc0c38d1 SR |
2075 | #ifdef CONFIG_DYNAMIC_FTRACE |
2076 | ||
2077 | static ssize_t | |
2078 | tracing_read_long(struct file *filp, char __user *ubuf, | |
2079 | size_t cnt, loff_t *ppos) | |
2080 | { | |
2081 | unsigned long *p = filp->private_data; | |
2082 | char buf[64]; | |
2083 | int r; | |
2084 | ||
2085 | r = sprintf(buf, "%ld\n", *p); | |
4bf39a94 IM |
2086 | |
2087 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
bc0c38d1 SR |
2088 | } |
2089 | ||
2090 | static struct file_operations tracing_read_long_fops = { | |
4bf39a94 IM |
2091 | .open = tracing_open_generic, |
2092 | .read = tracing_read_long, | |
bc0c38d1 SR |
2093 | }; |
2094 | #endif | |
2095 | ||
2096 | static struct dentry *d_tracer; | |
2097 | ||
2098 | struct dentry *tracing_init_dentry(void) | |
2099 | { | |
2100 | static int once; | |
2101 | ||
2102 | if (d_tracer) | |
2103 | return d_tracer; | |
2104 | ||
2105 | d_tracer = debugfs_create_dir("tracing", NULL); | |
2106 | ||
2107 | if (!d_tracer && !once) { | |
2108 | once = 1; | |
2109 | pr_warning("Could not create debugfs directory 'tracing'\n"); | |
2110 | return NULL; | |
2111 | } | |
2112 | ||
2113 | return d_tracer; | |
2114 | } | |
2115 | ||
60a11774 SR |
2116 | #ifdef CONFIG_FTRACE_SELFTEST |
2117 | /* Let selftest have access to static functions in this file */ | |
2118 | #include "trace_selftest.c" | |
2119 | #endif | |
2120 | ||
bc0c38d1 SR |
2121 | static __init void tracer_init_debugfs(void) |
2122 | { | |
2123 | struct dentry *d_tracer; | |
2124 | struct dentry *entry; | |
2125 | ||
2126 | d_tracer = tracing_init_dentry(); | |
2127 | ||
2128 | entry = debugfs_create_file("tracing_enabled", 0644, d_tracer, | |
2129 | &global_trace, &tracing_ctrl_fops); | |
2130 | if (!entry) | |
2131 | pr_warning("Could not create debugfs 'tracing_enabled' entry\n"); | |
2132 | ||
2133 | entry = debugfs_create_file("iter_ctrl", 0644, d_tracer, | |
2134 | NULL, &tracing_iter_fops); | |
2135 | if (!entry) | |
2136 | pr_warning("Could not create debugfs 'iter_ctrl' entry\n"); | |
2137 | ||
2138 | entry = debugfs_create_file("latency_trace", 0444, d_tracer, | |
2139 | &global_trace, &tracing_lt_fops); | |
2140 | if (!entry) | |
2141 | pr_warning("Could not create debugfs 'latency_trace' entry\n"); | |
2142 | ||
2143 | entry = debugfs_create_file("trace", 0444, d_tracer, | |
2144 | &global_trace, &tracing_fops); | |
2145 | if (!entry) | |
2146 | pr_warning("Could not create debugfs 'trace' entry\n"); | |
2147 | ||
2148 | entry = debugfs_create_file("available_tracers", 0444, d_tracer, | |
2149 | &global_trace, &show_traces_fops); | |
2150 | if (!entry) | |
2151 | pr_warning("Could not create debugfs 'trace' entry\n"); | |
2152 | ||
2153 | entry = debugfs_create_file("current_tracer", 0444, d_tracer, | |
2154 | &global_trace, &set_tracer_fops); | |
2155 | if (!entry) | |
2156 | pr_warning("Could not create debugfs 'trace' entry\n"); | |
2157 | ||
2158 | entry = debugfs_create_file("tracing_max_latency", 0644, d_tracer, | |
2159 | &tracing_max_latency, | |
2160 | &tracing_max_lat_fops); | |
2161 | if (!entry) | |
2162 | pr_warning("Could not create debugfs " | |
2163 | "'tracing_max_latency' entry\n"); | |
2164 | ||
2165 | entry = debugfs_create_file("tracing_thresh", 0644, d_tracer, | |
2166 | &tracing_thresh, &tracing_max_lat_fops); | |
2167 | if (!entry) | |
2168 | pr_warning("Could not create debugfs " | |
2169 | "'tracing_threash' entry\n"); | |
7bd2f24c IM |
2170 | entry = debugfs_create_file("README", 0644, d_tracer, |
2171 | NULL, &tracing_readme_fops); | |
2172 | if (!entry) | |
2173 | pr_warning("Could not create debugfs 'README' entry\n"); | |
2174 | ||
b3806b43 SR |
2175 | entry = debugfs_create_file("trace_pipe", 0644, d_tracer, |
2176 | NULL, &tracing_pipe_fops); | |
2177 | if (!entry) | |
2178 | pr_warning("Could not create debugfs " | |
2179 | "'tracing_threash' entry\n"); | |
bc0c38d1 SR |
2180 | |
2181 | #ifdef CONFIG_DYNAMIC_FTRACE | |
2182 | entry = debugfs_create_file("dyn_ftrace_total_info", 0444, d_tracer, | |
2183 | &ftrace_update_tot_cnt, | |
2184 | &tracing_read_long_fops); | |
2185 | if (!entry) | |
2186 | pr_warning("Could not create debugfs " | |
2187 | "'dyn_ftrace_total_info' entry\n"); | |
2188 | #endif | |
2189 | } | |
2190 | ||
2191 | /* dummy trace to disable tracing */ | |
2192 | static struct tracer no_tracer __read_mostly = | |
2193 | { | |
4bf39a94 | 2194 | .name = "none", |
bc0c38d1 SR |
2195 | }; |
2196 | ||
4c11d7ae | 2197 | static int trace_alloc_page(void) |
bc0c38d1 | 2198 | { |
4c11d7ae | 2199 | struct trace_array_cpu *data; |
4c11d7ae SR |
2200 | struct page *page, *tmp; |
2201 | LIST_HEAD(pages); | |
c7aafc54 | 2202 | void *array; |
4c11d7ae SR |
2203 | int i; |
2204 | ||
2205 | /* first allocate a page for each CPU */ | |
2206 | for_each_possible_cpu(i) { | |
2207 | array = (void *)__get_free_page(GFP_KERNEL); | |
2208 | if (array == NULL) { | |
2209 | printk(KERN_ERR "tracer: failed to allocate page" | |
2210 | "for trace buffer!\n"); | |
2211 | goto free_pages; | |
2212 | } | |
2213 | ||
2214 | page = virt_to_page(array); | |
2215 | list_add(&page->lru, &pages); | |
2216 | ||
2217 | /* Only allocate if we are actually using the max trace */ | |
2218 | #ifdef CONFIG_TRACER_MAX_TRACE | |
2219 | array = (void *)__get_free_page(GFP_KERNEL); | |
2220 | if (array == NULL) { | |
2221 | printk(KERN_ERR "tracer: failed to allocate page" | |
2222 | "for trace buffer!\n"); | |
2223 | goto free_pages; | |
2224 | } | |
2225 | page = virt_to_page(array); | |
2226 | list_add(&page->lru, &pages); | |
2227 | #endif | |
2228 | } | |
2229 | ||
2230 | /* Now that we successfully allocate a page per CPU, add them */ | |
2231 | for_each_possible_cpu(i) { | |
2232 | data = global_trace.data[i]; | |
b3806b43 | 2233 | spin_lock_init(&data->lock); |
d4c5a2f5 | 2234 | lockdep_set_class(&data->lock, &data->lock_key); |
4c11d7ae | 2235 | page = list_entry(pages.next, struct page, lru); |
c7aafc54 | 2236 | list_del_init(&page->lru); |
4c11d7ae SR |
2237 | list_add_tail(&page->lru, &data->trace_pages); |
2238 | ClearPageLRU(page); | |
2239 | ||
2240 | #ifdef CONFIG_TRACER_MAX_TRACE | |
2241 | data = max_tr.data[i]; | |
b3806b43 | 2242 | spin_lock_init(&data->lock); |
d4c5a2f5 | 2243 | lockdep_set_class(&data->lock, &data->lock_key); |
4c11d7ae | 2244 | page = list_entry(pages.next, struct page, lru); |
c7aafc54 | 2245 | list_del_init(&page->lru); |
4c11d7ae SR |
2246 | list_add_tail(&page->lru, &data->trace_pages); |
2247 | SetPageLRU(page); | |
2248 | #endif | |
2249 | } | |
2250 | global_trace.entries += ENTRIES_PER_PAGE; | |
2251 | ||
2252 | return 0; | |
2253 | ||
2254 | free_pages: | |
2255 | list_for_each_entry_safe(page, tmp, &pages, lru) { | |
c7aafc54 | 2256 | list_del_init(&page->lru); |
4c11d7ae SR |
2257 | __free_page(page); |
2258 | } | |
2259 | return -ENOMEM; | |
bc0c38d1 SR |
2260 | } |
2261 | ||
2262 | __init static int tracer_alloc_buffers(void) | |
2263 | { | |
4c11d7ae SR |
2264 | struct trace_array_cpu *data; |
2265 | void *array; | |
2266 | struct page *page; | |
2267 | int pages = 0; | |
60a11774 | 2268 | int ret = -ENOMEM; |
bc0c38d1 SR |
2269 | int i; |
2270 | ||
4c11d7ae | 2271 | /* Allocate the first page for all buffers */ |
bc0c38d1 | 2272 | for_each_possible_cpu(i) { |
4c11d7ae | 2273 | data = global_trace.data[i] = &per_cpu(global_trace_cpu, i); |
bc0c38d1 SR |
2274 | max_tr.data[i] = &per_cpu(max_data, i); |
2275 | ||
4c11d7ae | 2276 | array = (void *)__get_free_page(GFP_KERNEL); |
bc0c38d1 | 2277 | if (array == NULL) { |
4c11d7ae SR |
2278 | printk(KERN_ERR "tracer: failed to allocate page" |
2279 | "for trace buffer!\n"); | |
bc0c38d1 SR |
2280 | goto free_buffers; |
2281 | } | |
4c11d7ae SR |
2282 | |
2283 | /* set the array to the list */ | |
2284 | INIT_LIST_HEAD(&data->trace_pages); | |
2285 | page = virt_to_page(array); | |
2286 | list_add(&page->lru, &data->trace_pages); | |
2287 | /* use the LRU flag to differentiate the two buffers */ | |
2288 | ClearPageLRU(page); | |
bc0c38d1 SR |
2289 | |
2290 | /* Only allocate if we are actually using the max trace */ | |
2291 | #ifdef CONFIG_TRACER_MAX_TRACE | |
4c11d7ae | 2292 | array = (void *)__get_free_page(GFP_KERNEL); |
bc0c38d1 | 2293 | if (array == NULL) { |
4c11d7ae SR |
2294 | printk(KERN_ERR "tracer: failed to allocate page" |
2295 | "for trace buffer!\n"); | |
bc0c38d1 SR |
2296 | goto free_buffers; |
2297 | } | |
4c11d7ae SR |
2298 | |
2299 | INIT_LIST_HEAD(&max_tr.data[i]->trace_pages); | |
2300 | page = virt_to_page(array); | |
2301 | list_add(&page->lru, &max_tr.data[i]->trace_pages); | |
2302 | SetPageLRU(page); | |
bc0c38d1 SR |
2303 | #endif |
2304 | } | |
2305 | ||
2306 | /* | |
2307 | * Since we allocate by orders of pages, we may be able to | |
2308 | * round up a bit. | |
2309 | */ | |
4c11d7ae | 2310 | global_trace.entries = ENTRIES_PER_PAGE; |
4c11d7ae SR |
2311 | pages++; |
2312 | ||
2313 | while (global_trace.entries < trace_nr_entries) { | |
2314 | if (trace_alloc_page()) | |
2315 | break; | |
2316 | pages++; | |
2317 | } | |
89b2f978 | 2318 | max_tr.entries = global_trace.entries; |
bc0c38d1 | 2319 | |
4c11d7ae SR |
2320 | pr_info("tracer: %d pages allocated for %ld", |
2321 | pages, trace_nr_entries); | |
bc0c38d1 SR |
2322 | pr_info(" entries of %ld bytes\n", (long)TRACE_ENTRY_SIZE); |
2323 | pr_info(" actual entries %ld\n", global_trace.entries); | |
2324 | ||
2325 | tracer_init_debugfs(); | |
2326 | ||
2327 | trace_init_cmdlines(); | |
2328 | ||
2329 | register_tracer(&no_tracer); | |
2330 | current_trace = &no_tracer; | |
2331 | ||
60a11774 SR |
2332 | /* All seems OK, enable tracing */ |
2333 | tracing_disabled = 0; | |
2334 | ||
bc0c38d1 SR |
2335 | return 0; |
2336 | ||
2337 | free_buffers: | |
2338 | for (i-- ; i >= 0; i--) { | |
4c11d7ae | 2339 | struct page *page, *tmp; |
bc0c38d1 SR |
2340 | struct trace_array_cpu *data = global_trace.data[i]; |
2341 | ||
c7aafc54 | 2342 | if (data) { |
4c11d7ae SR |
2343 | list_for_each_entry_safe(page, tmp, |
2344 | &data->trace_pages, lru) { | |
c7aafc54 | 2345 | list_del_init(&page->lru); |
4c11d7ae SR |
2346 | __free_page(page); |
2347 | } | |
bc0c38d1 SR |
2348 | } |
2349 | ||
2350 | #ifdef CONFIG_TRACER_MAX_TRACE | |
2351 | data = max_tr.data[i]; | |
c7aafc54 | 2352 | if (data) { |
4c11d7ae SR |
2353 | list_for_each_entry_safe(page, tmp, |
2354 | &data->trace_pages, lru) { | |
c7aafc54 | 2355 | list_del_init(&page->lru); |
4c11d7ae SR |
2356 | __free_page(page); |
2357 | } | |
bc0c38d1 SR |
2358 | } |
2359 | #endif | |
2360 | } | |
60a11774 | 2361 | return ret; |
bc0c38d1 | 2362 | } |
60a11774 | 2363 | fs_initcall(tracer_alloc_buffers); |