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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 | ||
45 | static atomic_t tracer_counter; | |
46 | static struct trace_array global_trace; | |
47 | ||
48 | static DEFINE_PER_CPU(struct trace_array_cpu, global_trace_cpu); | |
49 | ||
50 | static struct trace_array max_tr; | |
51 | ||
52 | static DEFINE_PER_CPU(struct trace_array_cpu, max_data); | |
53 | ||
54 | static int tracer_enabled; | |
4c11d7ae | 55 | static unsigned long trace_nr_entries = 16384UL; |
bc0c38d1 SR |
56 | |
57 | static struct tracer *trace_types __read_mostly; | |
58 | static struct tracer *current_trace __read_mostly; | |
59 | static int max_tracer_type_len; | |
60 | ||
61 | static DEFINE_MUTEX(trace_types_lock); | |
62 | ||
4c11d7ae SR |
63 | #define ENTRIES_PER_PAGE (PAGE_SIZE / sizeof(struct trace_entry)) |
64 | ||
bc0c38d1 SR |
65 | static int __init set_nr_entries(char *str) |
66 | { | |
67 | if (!str) | |
68 | return 0; | |
69 | trace_nr_entries = simple_strtoul(str, &str, 0); | |
70 | return 1; | |
71 | } | |
72 | __setup("trace_entries=", set_nr_entries); | |
73 | ||
57f50be1 SR |
74 | unsigned long nsecs_to_usecs(unsigned long nsecs) |
75 | { | |
76 | return nsecs / 1000; | |
77 | } | |
78 | ||
bc0c38d1 SR |
79 | enum trace_type { |
80 | __TRACE_FIRST_TYPE = 0, | |
81 | ||
82 | TRACE_FN, | |
83 | TRACE_CTX, | |
84 | ||
85 | __TRACE_LAST_TYPE | |
86 | }; | |
87 | ||
88 | enum trace_flag_type { | |
89 | TRACE_FLAG_IRQS_OFF = 0x01, | |
90 | TRACE_FLAG_NEED_RESCHED = 0x02, | |
91 | TRACE_FLAG_HARDIRQ = 0x04, | |
92 | TRACE_FLAG_SOFTIRQ = 0x08, | |
93 | }; | |
94 | ||
95 | enum trace_iterator_flags { | |
96 | TRACE_ITER_PRINT_PARENT = 0x01, | |
97 | TRACE_ITER_SYM_OFFSET = 0x02, | |
98 | TRACE_ITER_SYM_ADDR = 0x04, | |
99 | TRACE_ITER_VERBOSE = 0x08, | |
100 | }; | |
101 | ||
102 | #define TRACE_ITER_SYM_MASK \ | |
103 | (TRACE_ITER_PRINT_PARENT|TRACE_ITER_SYM_OFFSET|TRACE_ITER_SYM_ADDR) | |
104 | ||
105 | /* These must match the bit postions above */ | |
106 | static const char *trace_options[] = { | |
107 | "print-parent", | |
108 | "sym-offset", | |
109 | "sym-addr", | |
110 | "verbose", | |
111 | NULL | |
112 | }; | |
113 | ||
114 | static unsigned trace_flags; | |
115 | ||
4c11d7ae | 116 | static DEFINE_SPINLOCK(ftrace_max_lock); |
bc0c38d1 SR |
117 | |
118 | /* | |
119 | * Copy the new maximum trace into the separate maximum-trace | |
120 | * structure. (this way the maximum trace is permanently saved, | |
121 | * for later retrieval via /debugfs/tracing/latency_trace) | |
122 | */ | |
123 | static void notrace | |
124 | __update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) | |
125 | { | |
126 | struct trace_array_cpu *data = tr->data[cpu]; | |
127 | ||
128 | max_tr.cpu = cpu; | |
129 | max_tr.time_start = data->preempt_timestamp; | |
130 | ||
131 | data = max_tr.data[cpu]; | |
132 | data->saved_latency = tracing_max_latency; | |
133 | ||
134 | memcpy(data->comm, tsk->comm, TASK_COMM_LEN); | |
135 | data->pid = tsk->pid; | |
136 | data->uid = tsk->uid; | |
137 | data->nice = tsk->static_prio - 20 - MAX_RT_PRIO; | |
138 | data->policy = tsk->policy; | |
139 | data->rt_priority = tsk->rt_priority; | |
140 | ||
141 | /* record this tasks comm */ | |
142 | tracing_record_cmdline(current); | |
143 | } | |
144 | ||
145 | notrace void | |
146 | update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) | |
147 | { | |
148 | struct trace_array_cpu *data; | |
149 | void *save_trace; | |
4c11d7ae | 150 | struct list_head save_pages; |
bc0c38d1 SR |
151 | int i; |
152 | ||
4c11d7ae SR |
153 | WARN_ON_ONCE(!irqs_disabled()); |
154 | spin_lock(&ftrace_max_lock); | |
bc0c38d1 SR |
155 | /* clear out all the previous traces */ |
156 | for_each_possible_cpu(i) { | |
157 | data = tr->data[i]; | |
158 | save_trace = max_tr.data[i]->trace; | |
4c11d7ae | 159 | save_pages = max_tr.data[i]->trace_pages; |
bc0c38d1 SR |
160 | memcpy(max_tr.data[i], data, sizeof(*data)); |
161 | data->trace = save_trace; | |
4c11d7ae | 162 | data->trace_pages = save_pages; |
89b2f978 | 163 | tracing_reset(data); |
bc0c38d1 SR |
164 | } |
165 | ||
166 | __update_max_tr(tr, tsk, cpu); | |
4c11d7ae | 167 | spin_unlock(&ftrace_max_lock); |
bc0c38d1 SR |
168 | } |
169 | ||
170 | /** | |
171 | * update_max_tr_single - only copy one trace over, and reset the rest | |
172 | * @tr - tracer | |
173 | * @tsk - task with the latency | |
174 | * @cpu - the cpu of the buffer to copy. | |
175 | */ | |
176 | notrace void | |
177 | update_max_tr_single(struct trace_array *tr, struct task_struct *tsk, int cpu) | |
178 | { | |
179 | struct trace_array_cpu *data = tr->data[cpu]; | |
180 | void *save_trace; | |
4c11d7ae | 181 | struct list_head save_pages; |
bc0c38d1 SR |
182 | int i; |
183 | ||
4c11d7ae SR |
184 | WARN_ON_ONCE(!irqs_disabled()); |
185 | spin_lock(&ftrace_max_lock); | |
bc0c38d1 SR |
186 | for_each_possible_cpu(i) |
187 | tracing_reset(max_tr.data[i]); | |
188 | ||
189 | save_trace = max_tr.data[cpu]->trace; | |
4c11d7ae | 190 | save_pages = max_tr.data[cpu]->trace_pages; |
bc0c38d1 SR |
191 | memcpy(max_tr.data[cpu], data, sizeof(*data)); |
192 | data->trace = save_trace; | |
4c11d7ae | 193 | data->trace_pages = save_pages; |
89b2f978 | 194 | tracing_reset(data); |
bc0c38d1 SR |
195 | |
196 | __update_max_tr(tr, tsk, cpu); | |
4c11d7ae | 197 | spin_unlock(&ftrace_max_lock); |
bc0c38d1 SR |
198 | } |
199 | ||
200 | int register_tracer(struct tracer *type) | |
201 | { | |
202 | struct tracer *t; | |
203 | int len; | |
204 | int ret = 0; | |
205 | ||
206 | if (!type->name) { | |
207 | pr_info("Tracer must have a name\n"); | |
208 | return -1; | |
209 | } | |
210 | ||
211 | mutex_lock(&trace_types_lock); | |
212 | for (t = trace_types; t; t = t->next) { | |
213 | if (strcmp(type->name, t->name) == 0) { | |
214 | /* already found */ | |
215 | pr_info("Trace %s already registered\n", | |
216 | type->name); | |
217 | ret = -1; | |
218 | goto out; | |
219 | } | |
220 | } | |
221 | ||
60a11774 SR |
222 | #ifdef CONFIG_FTRACE_STARTUP_TEST |
223 | if (type->selftest) { | |
224 | struct tracer *saved_tracer = current_trace; | |
225 | struct trace_array_cpu *data; | |
226 | struct trace_array *tr = &global_trace; | |
227 | int saved_ctrl = tr->ctrl; | |
228 | int i; | |
229 | /* | |
230 | * Run a selftest on this tracer. | |
231 | * Here we reset the trace buffer, and set the current | |
232 | * tracer to be this tracer. The tracer can then run some | |
233 | * internal tracing to verify that everything is in order. | |
234 | * If we fail, we do not register this tracer. | |
235 | */ | |
236 | for_each_possible_cpu(i) { | |
237 | if (!data->trace) | |
238 | continue; | |
239 | data = tr->data[i]; | |
240 | tracing_reset(data); | |
241 | } | |
242 | current_trace = type; | |
243 | tr->ctrl = 0; | |
244 | /* the test is responsible for initializing and enabling */ | |
245 | pr_info("Testing tracer %s: ", type->name); | |
246 | ret = type->selftest(type, tr); | |
247 | /* the test is responsible for resetting too */ | |
248 | current_trace = saved_tracer; | |
249 | tr->ctrl = saved_ctrl; | |
250 | if (ret) { | |
251 | printk(KERN_CONT "FAILED!\n"); | |
252 | goto out; | |
253 | } | |
254 | printk(KERN_CONT "PASSED\n"); | |
255 | } | |
256 | #endif | |
257 | ||
bc0c38d1 SR |
258 | type->next = trace_types; |
259 | trace_types = type; | |
260 | len = strlen(type->name); | |
261 | if (len > max_tracer_type_len) | |
262 | max_tracer_type_len = len; | |
60a11774 | 263 | |
bc0c38d1 SR |
264 | out: |
265 | mutex_unlock(&trace_types_lock); | |
266 | ||
267 | return ret; | |
268 | } | |
269 | ||
270 | void unregister_tracer(struct tracer *type) | |
271 | { | |
272 | struct tracer **t; | |
273 | int len; | |
274 | ||
275 | mutex_lock(&trace_types_lock); | |
276 | for (t = &trace_types; *t; t = &(*t)->next) { | |
277 | if (*t == type) | |
278 | goto found; | |
279 | } | |
280 | pr_info("Trace %s not registered\n", type->name); | |
281 | goto out; | |
282 | ||
283 | found: | |
284 | *t = (*t)->next; | |
285 | if (strlen(type->name) != max_tracer_type_len) | |
286 | goto out; | |
287 | ||
288 | max_tracer_type_len = 0; | |
289 | for (t = &trace_types; *t; t = &(*t)->next) { | |
290 | len = strlen((*t)->name); | |
291 | if (len > max_tracer_type_len) | |
292 | max_tracer_type_len = len; | |
293 | } | |
294 | out: | |
295 | mutex_unlock(&trace_types_lock); | |
296 | } | |
297 | ||
298 | void notrace tracing_reset(struct trace_array_cpu *data) | |
299 | { | |
300 | data->trace_idx = 0; | |
4c11d7ae SR |
301 | data->trace_current = data->trace; |
302 | data->trace_current_idx = 0; | |
bc0c38d1 SR |
303 | } |
304 | ||
305 | #ifdef CONFIG_FTRACE | |
306 | static void notrace | |
307 | function_trace_call(unsigned long ip, unsigned long parent_ip) | |
308 | { | |
309 | struct trace_array *tr = &global_trace; | |
310 | struct trace_array_cpu *data; | |
311 | unsigned long flags; | |
312 | long disabled; | |
313 | int cpu; | |
314 | ||
315 | if (unlikely(!tracer_enabled)) | |
316 | return; | |
317 | ||
18cef379 | 318 | local_irq_save(flags); |
bc0c38d1 SR |
319 | cpu = raw_smp_processor_id(); |
320 | data = tr->data[cpu]; | |
321 | disabled = atomic_inc_return(&data->disabled); | |
322 | ||
323 | if (likely(disabled == 1)) | |
324 | ftrace(tr, data, ip, parent_ip, flags); | |
325 | ||
326 | atomic_dec(&data->disabled); | |
18cef379 | 327 | local_irq_restore(flags); |
bc0c38d1 SR |
328 | } |
329 | ||
330 | static struct ftrace_ops trace_ops __read_mostly = | |
331 | { | |
332 | .func = function_trace_call, | |
333 | }; | |
334 | #endif | |
335 | ||
336 | notrace void tracing_start_function_trace(void) | |
337 | { | |
338 | register_ftrace_function(&trace_ops); | |
339 | } | |
340 | ||
341 | notrace void tracing_stop_function_trace(void) | |
342 | { | |
343 | unregister_ftrace_function(&trace_ops); | |
344 | } | |
345 | ||
346 | #define SAVED_CMDLINES 128 | |
347 | static unsigned map_pid_to_cmdline[PID_MAX_DEFAULT+1]; | |
348 | static unsigned map_cmdline_to_pid[SAVED_CMDLINES]; | |
349 | static char saved_cmdlines[SAVED_CMDLINES][TASK_COMM_LEN]; | |
350 | static int cmdline_idx; | |
351 | static DEFINE_SPINLOCK(trace_cmdline_lock); | |
352 | atomic_t trace_record_cmdline_disabled; | |
353 | ||
354 | static void trace_init_cmdlines(void) | |
355 | { | |
356 | memset(&map_pid_to_cmdline, -1, sizeof(map_pid_to_cmdline)); | |
357 | memset(&map_cmdline_to_pid, -1, sizeof(map_cmdline_to_pid)); | |
358 | cmdline_idx = 0; | |
359 | } | |
360 | ||
361 | notrace void trace_stop_cmdline_recording(void); | |
362 | ||
363 | static void notrace trace_save_cmdline(struct task_struct *tsk) | |
364 | { | |
365 | unsigned map; | |
366 | unsigned idx; | |
367 | ||
368 | if (!tsk->pid || unlikely(tsk->pid > PID_MAX_DEFAULT)) | |
369 | return; | |
370 | ||
371 | /* | |
372 | * It's not the end of the world if we don't get | |
373 | * the lock, but we also don't want to spin | |
374 | * nor do we want to disable interrupts, | |
375 | * so if we miss here, then better luck next time. | |
376 | */ | |
377 | if (!spin_trylock(&trace_cmdline_lock)) | |
378 | return; | |
379 | ||
380 | idx = map_pid_to_cmdline[tsk->pid]; | |
381 | if (idx >= SAVED_CMDLINES) { | |
382 | idx = (cmdline_idx + 1) % SAVED_CMDLINES; | |
383 | ||
384 | map = map_cmdline_to_pid[idx]; | |
385 | if (map <= PID_MAX_DEFAULT) | |
386 | map_pid_to_cmdline[map] = (unsigned)-1; | |
387 | ||
388 | map_pid_to_cmdline[tsk->pid] = idx; | |
389 | ||
390 | cmdline_idx = idx; | |
391 | } | |
392 | ||
393 | memcpy(&saved_cmdlines[idx], tsk->comm, TASK_COMM_LEN); | |
394 | ||
395 | spin_unlock(&trace_cmdline_lock); | |
396 | } | |
397 | ||
398 | static notrace char *trace_find_cmdline(int pid) | |
399 | { | |
400 | char *cmdline = "<...>"; | |
401 | unsigned map; | |
402 | ||
403 | if (!pid) | |
404 | return "<idle>"; | |
405 | ||
406 | if (pid > PID_MAX_DEFAULT) | |
407 | goto out; | |
408 | ||
409 | map = map_pid_to_cmdline[pid]; | |
410 | if (map >= SAVED_CMDLINES) | |
411 | goto out; | |
412 | ||
413 | cmdline = saved_cmdlines[map]; | |
414 | ||
415 | out: | |
416 | return cmdline; | |
417 | } | |
418 | ||
419 | notrace void tracing_record_cmdline(struct task_struct *tsk) | |
420 | { | |
421 | if (atomic_read(&trace_record_cmdline_disabled)) | |
422 | return; | |
423 | ||
424 | trace_save_cmdline(tsk); | |
425 | } | |
426 | ||
427 | static inline notrace struct trace_entry * | |
428 | tracing_get_trace_entry(struct trace_array *tr, | |
429 | struct trace_array_cpu *data) | |
430 | { | |
431 | unsigned long idx, idx_next; | |
432 | struct trace_entry *entry; | |
4c11d7ae SR |
433 | struct page *page; |
434 | struct list_head *next; | |
bc0c38d1 | 435 | |
4c11d7ae SR |
436 | data->trace_idx++; |
437 | idx = data->trace_current_idx; | |
bc0c38d1 SR |
438 | idx_next = idx + 1; |
439 | ||
4c11d7ae SR |
440 | entry = data->trace_current + idx * TRACE_ENTRY_SIZE; |
441 | ||
442 | if (unlikely(idx_next >= ENTRIES_PER_PAGE)) { | |
443 | page = virt_to_page(data->trace_current); | |
444 | if (unlikely(&page->lru == data->trace_pages.prev)) | |
445 | next = data->trace_pages.next; | |
446 | else | |
447 | next = page->lru.next; | |
448 | page = list_entry(next, struct page, lru); | |
449 | data->trace_current = page_address(page); | |
bc0c38d1 SR |
450 | idx_next = 0; |
451 | } | |
452 | ||
4c11d7ae | 453 | data->trace_current_idx = idx_next; |
bc0c38d1 SR |
454 | |
455 | return entry; | |
456 | } | |
457 | ||
458 | static inline notrace void | |
459 | tracing_generic_entry_update(struct trace_entry *entry, | |
460 | unsigned long flags) | |
461 | { | |
462 | struct task_struct *tsk = current; | |
463 | unsigned long pc; | |
464 | ||
465 | pc = preempt_count(); | |
466 | ||
467 | entry->idx = atomic_inc_return(&tracer_counter); | |
468 | entry->preempt_count = pc & 0xff; | |
469 | entry->pid = tsk->pid; | |
470 | entry->t = now(raw_smp_processor_id()); | |
471 | entry->flags = (irqs_disabled_flags(flags) ? TRACE_FLAG_IRQS_OFF : 0) | | |
472 | ((pc & HARDIRQ_MASK) ? TRACE_FLAG_HARDIRQ : 0) | | |
473 | ((pc & SOFTIRQ_MASK) ? TRACE_FLAG_SOFTIRQ : 0) | | |
474 | (need_resched() ? TRACE_FLAG_NEED_RESCHED : 0); | |
475 | } | |
476 | ||
477 | notrace void | |
478 | ftrace(struct trace_array *tr, struct trace_array_cpu *data, | |
479 | unsigned long ip, unsigned long parent_ip, | |
480 | unsigned long flags) | |
481 | { | |
482 | struct trace_entry *entry; | |
483 | ||
484 | entry = tracing_get_trace_entry(tr, data); | |
485 | tracing_generic_entry_update(entry, flags); | |
486 | entry->type = TRACE_FN; | |
487 | entry->fn.ip = ip; | |
488 | entry->fn.parent_ip = parent_ip; | |
489 | } | |
490 | ||
491 | notrace void | |
492 | tracing_sched_switch_trace(struct trace_array *tr, | |
493 | struct trace_array_cpu *data, | |
494 | struct task_struct *prev, struct task_struct *next, | |
495 | unsigned long flags) | |
496 | { | |
497 | struct trace_entry *entry; | |
498 | ||
499 | entry = tracing_get_trace_entry(tr, data); | |
500 | tracing_generic_entry_update(entry, flags); | |
501 | entry->type = TRACE_CTX; | |
502 | entry->ctx.prev_pid = prev->pid; | |
503 | entry->ctx.prev_prio = prev->prio; | |
504 | entry->ctx.prev_state = prev->state; | |
505 | entry->ctx.next_pid = next->pid; | |
506 | entry->ctx.next_prio = next->prio; | |
507 | } | |
508 | ||
509 | enum trace_file_type { | |
510 | TRACE_FILE_LAT_FMT = 1, | |
511 | }; | |
512 | ||
513 | static struct trace_entry * | |
4c11d7ae SR |
514 | trace_entry_idx(struct trace_array *tr, struct trace_array_cpu *data, |
515 | struct trace_iterator *iter, int cpu) | |
bc0c38d1 | 516 | { |
4c11d7ae SR |
517 | struct page *page; |
518 | struct trace_entry *array; | |
bc0c38d1 | 519 | |
4c11d7ae SR |
520 | if (iter->next_idx[cpu] >= tr->entries || |
521 | iter->next_idx[cpu] >= data->trace_idx) | |
bc0c38d1 SR |
522 | return NULL; |
523 | ||
4c11d7ae SR |
524 | if (!iter->next_page[cpu]) { |
525 | /* | |
526 | * Initialize. If the count of elements in | |
527 | * this buffer is greater than the max entries | |
528 | * we had an underrun. Which means we looped around. | |
529 | * We can simply use the current pointer as our | |
530 | * starting point. | |
531 | */ | |
532 | if (data->trace_idx >= tr->entries) { | |
533 | page = virt_to_page(data->trace_current); | |
534 | iter->next_page[cpu] = &page->lru; | |
535 | iter->next_page_idx[cpu] = data->trace_current_idx; | |
536 | } else { | |
537 | iter->next_page[cpu] = data->trace_pages.next; | |
538 | iter->next_page_idx[cpu] = 0; | |
539 | } | |
540 | } | |
bc0c38d1 | 541 | |
4c11d7ae SR |
542 | page = list_entry(iter->next_page[cpu], struct page, lru); |
543 | array = page_address(page); | |
544 | ||
545 | return &array[iter->next_page_idx[cpu]]; | |
bc0c38d1 SR |
546 | } |
547 | ||
548 | static struct notrace trace_entry * | |
549 | find_next_entry(struct trace_iterator *iter, int *ent_cpu) | |
550 | { | |
551 | struct trace_array *tr = iter->tr; | |
552 | struct trace_entry *ent, *next = NULL; | |
553 | int next_cpu = -1; | |
554 | int cpu; | |
555 | ||
556 | for_each_possible_cpu(cpu) { | |
557 | if (!tr->data[cpu]->trace) | |
558 | continue; | |
4c11d7ae | 559 | ent = trace_entry_idx(tr, tr->data[cpu], iter, cpu); |
bc0c38d1 SR |
560 | if (ent && |
561 | (!next || (long)(next->idx - ent->idx) > 0)) { | |
562 | next = ent; | |
563 | next_cpu = cpu; | |
564 | } | |
565 | } | |
566 | ||
567 | if (ent_cpu) | |
568 | *ent_cpu = next_cpu; | |
569 | ||
570 | return next; | |
571 | } | |
572 | ||
573 | static void *find_next_entry_inc(struct trace_iterator *iter) | |
574 | { | |
575 | struct trace_entry *next; | |
576 | int next_cpu = -1; | |
577 | ||
578 | next = find_next_entry(iter, &next_cpu); | |
579 | ||
580 | if (next) { | |
bc0c38d1 | 581 | iter->idx++; |
4c11d7ae SR |
582 | iter->next_idx[next_cpu]++; |
583 | iter->next_page_idx[next_cpu]++; | |
584 | if (iter->next_page_idx[next_cpu] >= ENTRIES_PER_PAGE) { | |
585 | struct trace_array_cpu *data = iter->tr->data[next_cpu]; | |
586 | ||
587 | iter->next_page_idx[next_cpu] = 0; | |
588 | iter->next_page[next_cpu] = | |
589 | iter->next_page[next_cpu]->next; | |
590 | if (iter->next_page[next_cpu] == &data->trace_pages) | |
591 | iter->next_page[next_cpu] = | |
592 | data->trace_pages.next; | |
593 | } | |
bc0c38d1 SR |
594 | } |
595 | iter->ent = next; | |
596 | iter->cpu = next_cpu; | |
597 | ||
598 | return next ? iter : NULL; | |
599 | } | |
600 | ||
601 | static void notrace * | |
602 | s_next(struct seq_file *m, void *v, loff_t *pos) | |
603 | { | |
604 | struct trace_iterator *iter = m->private; | |
605 | void *ent; | |
606 | void *last_ent = iter->ent; | |
607 | int i = (int)*pos; | |
608 | ||
609 | (*pos)++; | |
610 | ||
611 | /* can't go backwards */ | |
612 | if (iter->idx > i) | |
613 | return NULL; | |
614 | ||
615 | if (iter->idx < 0) | |
616 | ent = find_next_entry_inc(iter); | |
617 | else | |
618 | ent = iter; | |
619 | ||
620 | while (ent && iter->idx < i) | |
621 | ent = find_next_entry_inc(iter); | |
622 | ||
623 | iter->pos = *pos; | |
624 | ||
625 | if (last_ent && !ent) | |
626 | seq_puts(m, "\n\nvim:ft=help\n"); | |
627 | ||
628 | return ent; | |
629 | } | |
630 | ||
631 | static void *s_start(struct seq_file *m, loff_t *pos) | |
632 | { | |
633 | struct trace_iterator *iter = m->private; | |
634 | void *p = NULL; | |
635 | loff_t l = 0; | |
636 | int i; | |
637 | ||
638 | mutex_lock(&trace_types_lock); | |
639 | ||
640 | if (!current_trace || current_trace != iter->trace) | |
641 | return NULL; | |
642 | ||
643 | atomic_inc(&trace_record_cmdline_disabled); | |
644 | ||
645 | /* let the tracer grab locks here if needed */ | |
646 | if (current_trace->start) | |
647 | current_trace->start(iter); | |
648 | ||
649 | if (*pos != iter->pos) { | |
650 | iter->ent = NULL; | |
651 | iter->cpu = 0; | |
652 | iter->idx = -1; | |
653 | ||
4c11d7ae | 654 | for_each_possible_cpu(i) { |
bc0c38d1 | 655 | iter->next_idx[i] = 0; |
4c11d7ae SR |
656 | iter->next_page[i] = NULL; |
657 | } | |
bc0c38d1 SR |
658 | |
659 | for (p = iter; p && l < *pos; p = s_next(m, p, &l)) | |
660 | ; | |
661 | ||
662 | } else { | |
4c11d7ae | 663 | l = *pos - 1; |
bc0c38d1 SR |
664 | p = s_next(m, p, &l); |
665 | } | |
666 | ||
667 | return p; | |
668 | } | |
669 | ||
670 | static void s_stop(struct seq_file *m, void *p) | |
671 | { | |
672 | struct trace_iterator *iter = m->private; | |
673 | ||
674 | atomic_dec(&trace_record_cmdline_disabled); | |
675 | ||
676 | /* let the tracer release locks here if needed */ | |
677 | if (current_trace && current_trace == iter->trace && iter->trace->stop) | |
678 | iter->trace->stop(iter); | |
679 | ||
680 | mutex_unlock(&trace_types_lock); | |
681 | } | |
682 | ||
683 | static void | |
684 | seq_print_sym_short(struct seq_file *m, const char *fmt, unsigned long address) | |
685 | { | |
686 | #ifdef CONFIG_KALLSYMS | |
687 | char str[KSYM_SYMBOL_LEN]; | |
688 | ||
689 | kallsyms_lookup(address, NULL, NULL, NULL, str); | |
690 | ||
691 | seq_printf(m, fmt, str); | |
692 | #endif | |
693 | } | |
694 | ||
695 | static void | |
696 | seq_print_sym_offset(struct seq_file *m, const char *fmt, unsigned long address) | |
697 | { | |
698 | #ifdef CONFIG_KALLSYMS | |
699 | char str[KSYM_SYMBOL_LEN]; | |
700 | ||
701 | sprint_symbol(str, address); | |
702 | seq_printf(m, fmt, str); | |
703 | #endif | |
704 | } | |
705 | ||
706 | #ifndef CONFIG_64BIT | |
707 | # define IP_FMT "%08lx" | |
708 | #else | |
709 | # define IP_FMT "%016lx" | |
710 | #endif | |
711 | ||
712 | static void notrace | |
713 | seq_print_ip_sym(struct seq_file *m, unsigned long ip, unsigned long sym_flags) | |
714 | { | |
715 | if (!ip) { | |
716 | seq_printf(m, "0"); | |
717 | return; | |
718 | } | |
719 | ||
720 | if (sym_flags & TRACE_ITER_SYM_OFFSET) | |
721 | seq_print_sym_offset(m, "%s", ip); | |
722 | else | |
723 | seq_print_sym_short(m, "%s", ip); | |
724 | ||
725 | if (sym_flags & TRACE_ITER_SYM_ADDR) | |
726 | seq_printf(m, " <" IP_FMT ">", ip); | |
727 | } | |
728 | ||
729 | static void notrace print_lat_help_header(struct seq_file *m) | |
730 | { | |
731 | seq_puts(m, "# _------=> CPU# \n"); | |
732 | seq_puts(m, "# / _-----=> irqs-off \n"); | |
733 | seq_puts(m, "# | / _----=> need-resched \n"); | |
734 | seq_puts(m, "# || / _---=> hardirq/softirq \n"); | |
735 | seq_puts(m, "# ||| / _--=> preempt-depth \n"); | |
736 | seq_puts(m, "# |||| / \n"); | |
737 | seq_puts(m, "# ||||| delay \n"); | |
738 | seq_puts(m, "# cmd pid ||||| time | caller \n"); | |
739 | seq_puts(m, "# \\ / ||||| \\ | / \n"); | |
740 | } | |
741 | ||
742 | static void notrace print_func_help_header(struct seq_file *m) | |
743 | { | |
744 | seq_puts(m, "# TASK-PID CPU# TIMESTAMP FUNCTION\n"); | |
745 | seq_puts(m, "# | | | | |\n"); | |
746 | } | |
747 | ||
748 | ||
749 | static void notrace | |
750 | print_trace_header(struct seq_file *m, struct trace_iterator *iter) | |
751 | { | |
752 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); | |
753 | struct trace_array *tr = iter->tr; | |
754 | struct trace_array_cpu *data = tr->data[tr->cpu]; | |
755 | struct tracer *type = current_trace; | |
4c11d7ae SR |
756 | unsigned long total = 0; |
757 | unsigned long entries = 0; | |
bc0c38d1 SR |
758 | int cpu; |
759 | const char *name = "preemption"; | |
760 | ||
761 | if (type) | |
762 | name = type->name; | |
763 | ||
764 | for_each_possible_cpu(cpu) { | |
765 | if (tr->data[cpu]->trace) { | |
4c11d7ae SR |
766 | total += tr->data[cpu]->trace_idx; |
767 | if (tr->data[cpu]->trace_idx > tr->entries) | |
bc0c38d1 | 768 | entries += tr->entries; |
4c11d7ae | 769 | else |
bc0c38d1 SR |
770 | entries += tr->data[cpu]->trace_idx; |
771 | } | |
772 | } | |
773 | ||
774 | seq_printf(m, "%s latency trace v1.1.5 on %s\n", | |
775 | name, UTS_RELEASE); | |
776 | seq_puts(m, "-----------------------------------" | |
777 | "---------------------------------\n"); | |
778 | seq_printf(m, " latency: %lu us, #%lu/%lu, CPU#%d |" | |
779 | " (M:%s VP:%d, KP:%d, SP:%d HP:%d", | |
57f50be1 | 780 | nsecs_to_usecs(data->saved_latency), |
bc0c38d1 | 781 | entries, |
4c11d7ae | 782 | total, |
bc0c38d1 SR |
783 | tr->cpu, |
784 | #if defined(CONFIG_PREEMPT_NONE) | |
785 | "server", | |
786 | #elif defined(CONFIG_PREEMPT_VOLUNTARY) | |
787 | "desktop", | |
788 | #elif defined(CONFIG_PREEMPT_DESKTOP) | |
789 | "preempt", | |
790 | #else | |
791 | "unknown", | |
792 | #endif | |
793 | /* These are reserved for later use */ | |
794 | 0, 0, 0, 0); | |
795 | #ifdef CONFIG_SMP | |
796 | seq_printf(m, " #P:%d)\n", num_online_cpus()); | |
797 | #else | |
798 | seq_puts(m, ")\n"); | |
799 | #endif | |
800 | seq_puts(m, " -----------------\n"); | |
801 | seq_printf(m, " | task: %.16s-%d " | |
802 | "(uid:%d nice:%ld policy:%ld rt_prio:%ld)\n", | |
803 | data->comm, data->pid, data->uid, data->nice, | |
804 | data->policy, data->rt_priority); | |
805 | seq_puts(m, " -----------------\n"); | |
806 | ||
807 | if (data->critical_start) { | |
808 | seq_puts(m, " => started at: "); | |
809 | seq_print_ip_sym(m, data->critical_start, sym_flags); | |
810 | seq_puts(m, "\n => ended at: "); | |
811 | seq_print_ip_sym(m, data->critical_end, sym_flags); | |
812 | seq_puts(m, "\n"); | |
813 | } | |
814 | ||
815 | seq_puts(m, "\n"); | |
816 | } | |
817 | ||
bc0c38d1 SR |
818 | static void notrace |
819 | lat_print_generic(struct seq_file *m, struct trace_entry *entry, int cpu) | |
820 | { | |
821 | int hardirq, softirq; | |
822 | char *comm; | |
823 | ||
824 | comm = trace_find_cmdline(entry->pid); | |
825 | ||
826 | seq_printf(m, "%8.8s-%-5d ", comm, entry->pid); | |
827 | seq_printf(m, "%d", cpu); | |
828 | seq_printf(m, "%c%c", | |
829 | (entry->flags & TRACE_FLAG_IRQS_OFF) ? 'd' : '.', | |
830 | ((entry->flags & TRACE_FLAG_NEED_RESCHED) ? 'N' : '.')); | |
831 | ||
832 | hardirq = entry->flags & TRACE_FLAG_HARDIRQ; | |
833 | softirq = entry->flags & TRACE_FLAG_SOFTIRQ; | |
834 | if (hardirq && softirq) | |
835 | seq_putc(m, 'H'); | |
836 | else { | |
837 | if (hardirq) | |
838 | seq_putc(m, 'h'); | |
839 | else { | |
840 | if (softirq) | |
841 | seq_putc(m, 's'); | |
842 | else | |
843 | seq_putc(m, '.'); | |
844 | } | |
845 | } | |
846 | ||
847 | if (entry->preempt_count) | |
848 | seq_printf(m, "%x", entry->preempt_count); | |
849 | else | |
850 | seq_puts(m, "."); | |
851 | } | |
852 | ||
853 | unsigned long preempt_mark_thresh = 100; | |
854 | ||
855 | static void notrace | |
856 | lat_print_timestamp(struct seq_file *m, unsigned long long abs_usecs, | |
857 | unsigned long rel_usecs) | |
858 | { | |
859 | seq_printf(m, " %4lldus", abs_usecs); | |
860 | if (rel_usecs > preempt_mark_thresh) | |
861 | seq_puts(m, "!: "); | |
862 | else if (rel_usecs > 1) | |
863 | seq_puts(m, "+: "); | |
864 | else | |
865 | seq_puts(m, " : "); | |
866 | } | |
867 | ||
868 | static const char state_to_char[] = TASK_STATE_TO_CHAR_STR; | |
869 | ||
870 | static void notrace | |
871 | print_lat_fmt(struct seq_file *m, struct trace_iterator *iter, | |
872 | unsigned int trace_idx, int cpu) | |
873 | { | |
874 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); | |
875 | struct trace_entry *next_entry = find_next_entry(iter, NULL); | |
876 | unsigned long verbose = (trace_flags & TRACE_ITER_VERBOSE); | |
877 | struct trace_entry *entry = iter->ent; | |
878 | unsigned long abs_usecs; | |
879 | unsigned long rel_usecs; | |
880 | char *comm; | |
881 | int S; | |
882 | ||
883 | if (!next_entry) | |
884 | next_entry = entry; | |
885 | rel_usecs = ns2usecs(next_entry->t - entry->t); | |
886 | abs_usecs = ns2usecs(entry->t - iter->tr->time_start); | |
887 | ||
888 | if (verbose) { | |
889 | comm = trace_find_cmdline(entry->pid); | |
890 | seq_printf(m, "%16s %5d %d %d %08x %08x [%08lx]" | |
891 | " %ld.%03ldms (+%ld.%03ldms): ", | |
892 | comm, | |
893 | entry->pid, cpu, entry->flags, | |
894 | entry->preempt_count, trace_idx, | |
895 | ns2usecs(entry->t), | |
896 | abs_usecs/1000, | |
897 | abs_usecs % 1000, rel_usecs/1000, rel_usecs % 1000); | |
898 | } else { | |
899 | lat_print_generic(m, entry, cpu); | |
900 | lat_print_timestamp(m, abs_usecs, rel_usecs); | |
901 | } | |
902 | switch (entry->type) { | |
903 | case TRACE_FN: | |
904 | seq_print_ip_sym(m, entry->fn.ip, sym_flags); | |
905 | seq_puts(m, " ("); | |
906 | seq_print_ip_sym(m, entry->fn.parent_ip, sym_flags); | |
907 | seq_puts(m, ")\n"); | |
908 | break; | |
909 | case TRACE_CTX: | |
910 | S = entry->ctx.prev_state < sizeof(state_to_char) ? | |
911 | state_to_char[entry->ctx.prev_state] : 'X'; | |
912 | comm = trace_find_cmdline(entry->ctx.next_pid); | |
913 | seq_printf(m, " %d:%d:%c --> %d:%d %s\n", | |
914 | entry->ctx.prev_pid, | |
915 | entry->ctx.prev_prio, | |
916 | S, | |
917 | entry->ctx.next_pid, | |
918 | entry->ctx.next_prio, | |
919 | comm); | |
920 | break; | |
89b2f978 SR |
921 | default: |
922 | seq_printf(m, "Unknown type %d\n", entry->type); | |
bc0c38d1 SR |
923 | } |
924 | } | |
925 | ||
926 | static void notrace | |
927 | print_trace_fmt(struct seq_file *m, struct trace_iterator *iter) | |
928 | { | |
929 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); | |
930 | struct trace_entry *entry = iter->ent; | |
931 | unsigned long usec_rem; | |
932 | unsigned long long t; | |
933 | unsigned long secs; | |
934 | char *comm; | |
935 | int S; | |
936 | ||
937 | comm = trace_find_cmdline(iter->ent->pid); | |
938 | ||
939 | t = ns2usecs(entry->t); | |
940 | usec_rem = do_div(t, 1000000ULL); | |
941 | secs = (unsigned long)t; | |
942 | ||
943 | seq_printf(m, "%16s-%-5d ", comm, entry->pid); | |
944 | seq_printf(m, "[%02d] ", iter->cpu); | |
945 | seq_printf(m, "%5lu.%06lu: ", secs, usec_rem); | |
946 | ||
947 | switch (entry->type) { | |
948 | case TRACE_FN: | |
949 | seq_print_ip_sym(m, entry->fn.ip, sym_flags); | |
950 | if ((sym_flags & TRACE_ITER_PRINT_PARENT) && | |
951 | entry->fn.parent_ip) { | |
952 | seq_printf(m, " <-"); | |
953 | seq_print_ip_sym(m, entry->fn.parent_ip, sym_flags); | |
954 | } | |
955 | break; | |
956 | case TRACE_CTX: | |
957 | S = entry->ctx.prev_state < sizeof(state_to_char) ? | |
958 | state_to_char[entry->ctx.prev_state] : 'X'; | |
959 | seq_printf(m, " %d:%d:%c ==> %d:%d\n", | |
960 | entry->ctx.prev_pid, | |
961 | entry->ctx.prev_prio, | |
962 | S, | |
963 | entry->ctx.next_pid, | |
964 | entry->ctx.next_prio); | |
965 | break; | |
966 | } | |
967 | seq_printf(m, "\n"); | |
968 | } | |
969 | ||
970 | static int trace_empty(struct trace_iterator *iter) | |
971 | { | |
972 | struct trace_array_cpu *data; | |
973 | int cpu; | |
974 | ||
975 | for_each_possible_cpu(cpu) { | |
976 | data = iter->tr->data[cpu]; | |
977 | ||
978 | if (data->trace && | |
4c11d7ae | 979 | data->trace_idx) |
bc0c38d1 SR |
980 | return 0; |
981 | } | |
982 | return 1; | |
983 | } | |
984 | ||
985 | static int s_show(struct seq_file *m, void *v) | |
986 | { | |
987 | struct trace_iterator *iter = v; | |
988 | ||
989 | if (iter->ent == NULL) { | |
990 | if (iter->tr) { | |
991 | seq_printf(m, "# tracer: %s\n", iter->trace->name); | |
992 | seq_puts(m, "#\n"); | |
993 | } | |
994 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) { | |
995 | /* print nothing if the buffers are empty */ | |
996 | if (trace_empty(iter)) | |
997 | return 0; | |
998 | print_trace_header(m, iter); | |
999 | if (!(trace_flags & TRACE_ITER_VERBOSE)) | |
1000 | print_lat_help_header(m); | |
1001 | } else { | |
1002 | if (!(trace_flags & TRACE_ITER_VERBOSE)) | |
1003 | print_func_help_header(m); | |
1004 | } | |
1005 | } else { | |
1006 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) | |
1007 | print_lat_fmt(m, iter, iter->idx, iter->cpu); | |
1008 | else | |
1009 | print_trace_fmt(m, iter); | |
1010 | } | |
1011 | ||
1012 | return 0; | |
1013 | } | |
1014 | ||
1015 | static struct seq_operations tracer_seq_ops = { | |
1016 | .start = s_start, | |
1017 | .next = s_next, | |
1018 | .stop = s_stop, | |
1019 | .show = s_show, | |
1020 | }; | |
1021 | ||
1022 | static struct trace_iterator notrace * | |
1023 | __tracing_open(struct inode *inode, struct file *file, int *ret) | |
1024 | { | |
1025 | struct trace_iterator *iter; | |
1026 | ||
60a11774 SR |
1027 | if (tracing_disabled) { |
1028 | *ret = -ENODEV; | |
1029 | return NULL; | |
1030 | } | |
1031 | ||
bc0c38d1 SR |
1032 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); |
1033 | if (!iter) { | |
1034 | *ret = -ENOMEM; | |
1035 | goto out; | |
1036 | } | |
1037 | ||
1038 | mutex_lock(&trace_types_lock); | |
1039 | if (current_trace && current_trace->print_max) | |
1040 | iter->tr = &max_tr; | |
1041 | else | |
1042 | iter->tr = inode->i_private; | |
1043 | iter->trace = current_trace; | |
1044 | iter->pos = -1; | |
1045 | ||
1046 | /* TODO stop tracer */ | |
1047 | *ret = seq_open(file, &tracer_seq_ops); | |
1048 | if (!*ret) { | |
1049 | struct seq_file *m = file->private_data; | |
1050 | m->private = iter; | |
1051 | ||
1052 | /* stop the trace while dumping */ | |
1053 | if (iter->tr->ctrl) | |
1054 | tracer_enabled = 0; | |
1055 | ||
1056 | if (iter->trace && iter->trace->open) | |
1057 | iter->trace->open(iter); | |
1058 | } else { | |
1059 | kfree(iter); | |
1060 | iter = NULL; | |
1061 | } | |
1062 | mutex_unlock(&trace_types_lock); | |
1063 | ||
1064 | out: | |
1065 | return iter; | |
1066 | } | |
1067 | ||
1068 | int tracing_open_generic(struct inode *inode, struct file *filp) | |
1069 | { | |
60a11774 SR |
1070 | if (tracing_disabled) |
1071 | return -ENODEV; | |
1072 | ||
bc0c38d1 SR |
1073 | filp->private_data = inode->i_private; |
1074 | return 0; | |
1075 | } | |
1076 | ||
1077 | int tracing_release(struct inode *inode, struct file *file) | |
1078 | { | |
1079 | struct seq_file *m = (struct seq_file *)file->private_data; | |
1080 | struct trace_iterator *iter = m->private; | |
1081 | ||
1082 | mutex_lock(&trace_types_lock); | |
1083 | if (iter->trace && iter->trace->close) | |
1084 | iter->trace->close(iter); | |
1085 | ||
1086 | /* reenable tracing if it was previously enabled */ | |
1087 | if (iter->tr->ctrl) | |
1088 | tracer_enabled = 1; | |
1089 | mutex_unlock(&trace_types_lock); | |
1090 | ||
1091 | seq_release(inode, file); | |
1092 | kfree(iter); | |
1093 | return 0; | |
1094 | } | |
1095 | ||
1096 | static int tracing_open(struct inode *inode, struct file *file) | |
1097 | { | |
1098 | int ret; | |
1099 | ||
1100 | __tracing_open(inode, file, &ret); | |
1101 | ||
1102 | return ret; | |
1103 | } | |
1104 | ||
1105 | static int tracing_lt_open(struct inode *inode, struct file *file) | |
1106 | { | |
1107 | struct trace_iterator *iter; | |
1108 | int ret; | |
1109 | ||
1110 | iter = __tracing_open(inode, file, &ret); | |
1111 | ||
1112 | if (!ret) | |
1113 | iter->iter_flags |= TRACE_FILE_LAT_FMT; | |
1114 | ||
1115 | return ret; | |
1116 | } | |
1117 | ||
1118 | ||
1119 | static void notrace * | |
1120 | t_next(struct seq_file *m, void *v, loff_t *pos) | |
1121 | { | |
1122 | struct tracer *t = m->private; | |
1123 | ||
1124 | (*pos)++; | |
1125 | ||
1126 | if (t) | |
1127 | t = t->next; | |
1128 | ||
1129 | m->private = t; | |
1130 | ||
1131 | return t; | |
1132 | } | |
1133 | ||
1134 | static void *t_start(struct seq_file *m, loff_t *pos) | |
1135 | { | |
1136 | struct tracer *t = m->private; | |
1137 | loff_t l = 0; | |
1138 | ||
1139 | mutex_lock(&trace_types_lock); | |
1140 | for (; t && l < *pos; t = t_next(m, t, &l)) | |
1141 | ; | |
1142 | ||
1143 | return t; | |
1144 | } | |
1145 | ||
1146 | static void t_stop(struct seq_file *m, void *p) | |
1147 | { | |
1148 | mutex_unlock(&trace_types_lock); | |
1149 | } | |
1150 | ||
1151 | static int t_show(struct seq_file *m, void *v) | |
1152 | { | |
1153 | struct tracer *t = v; | |
1154 | ||
1155 | if (!t) | |
1156 | return 0; | |
1157 | ||
1158 | seq_printf(m, "%s", t->name); | |
1159 | if (t->next) | |
1160 | seq_putc(m, ' '); | |
1161 | else | |
1162 | seq_putc(m, '\n'); | |
1163 | ||
1164 | return 0; | |
1165 | } | |
1166 | ||
1167 | static struct seq_operations show_traces_seq_ops = { | |
1168 | .start = t_start, | |
1169 | .next = t_next, | |
1170 | .stop = t_stop, | |
1171 | .show = t_show, | |
1172 | }; | |
1173 | ||
1174 | static int show_traces_open(struct inode *inode, struct file *file) | |
1175 | { | |
1176 | int ret; | |
1177 | ||
60a11774 SR |
1178 | if (tracing_disabled) |
1179 | return -ENODEV; | |
1180 | ||
bc0c38d1 SR |
1181 | ret = seq_open(file, &show_traces_seq_ops); |
1182 | if (!ret) { | |
1183 | struct seq_file *m = file->private_data; | |
1184 | m->private = trace_types; | |
1185 | } | |
1186 | ||
1187 | return ret; | |
1188 | } | |
1189 | ||
1190 | static struct file_operations tracing_fops = { | |
1191 | .open = tracing_open, | |
1192 | .read = seq_read, | |
1193 | .llseek = seq_lseek, | |
1194 | .release = tracing_release, | |
1195 | }; | |
1196 | ||
1197 | static struct file_operations tracing_lt_fops = { | |
1198 | .open = tracing_lt_open, | |
1199 | .read = seq_read, | |
1200 | .llseek = seq_lseek, | |
1201 | .release = tracing_release, | |
1202 | }; | |
1203 | ||
1204 | static struct file_operations show_traces_fops = { | |
1205 | .open = show_traces_open, | |
1206 | .read = seq_read, | |
1207 | .release = seq_release, | |
1208 | }; | |
1209 | ||
1210 | static ssize_t | |
1211 | tracing_iter_ctrl_read(struct file *filp, char __user *ubuf, | |
1212 | size_t cnt, loff_t *ppos) | |
1213 | { | |
1214 | char *buf; | |
1215 | int r = 0; | |
1216 | int len = 0; | |
1217 | int i; | |
1218 | ||
1219 | /* calulate max size */ | |
1220 | for (i = 0; trace_options[i]; i++) { | |
1221 | len += strlen(trace_options[i]); | |
1222 | len += 3; /* "no" and space */ | |
1223 | } | |
1224 | ||
1225 | /* +2 for \n and \0 */ | |
1226 | buf = kmalloc(len + 2, GFP_KERNEL); | |
1227 | if (!buf) | |
1228 | return -ENOMEM; | |
1229 | ||
1230 | for (i = 0; trace_options[i]; i++) { | |
1231 | if (trace_flags & (1 << i)) | |
1232 | r += sprintf(buf + r, "%s ", trace_options[i]); | |
1233 | else | |
1234 | r += sprintf(buf + r, "no%s ", trace_options[i]); | |
1235 | } | |
1236 | ||
1237 | r += sprintf(buf + r, "\n"); | |
1238 | WARN_ON(r >= len + 2); | |
1239 | ||
1240 | r = simple_read_from_buffer(ubuf, cnt, ppos, | |
1241 | buf, r); | |
1242 | ||
1243 | kfree(buf); | |
1244 | ||
1245 | return r; | |
1246 | } | |
1247 | ||
1248 | static ssize_t | |
1249 | tracing_iter_ctrl_write(struct file *filp, const char __user *ubuf, | |
1250 | size_t cnt, loff_t *ppos) | |
1251 | { | |
1252 | char buf[64]; | |
1253 | char *cmp = buf; | |
1254 | int neg = 0; | |
1255 | int i; | |
1256 | ||
1257 | if (cnt > 63) | |
1258 | cnt = 63; | |
1259 | ||
1260 | if (copy_from_user(&buf, ubuf, cnt)) | |
1261 | return -EFAULT; | |
1262 | ||
1263 | buf[cnt] = 0; | |
1264 | ||
1265 | if (strncmp(buf, "no", 2) == 0) { | |
1266 | neg = 1; | |
1267 | cmp += 2; | |
1268 | } | |
1269 | ||
1270 | for (i = 0; trace_options[i]; i++) { | |
1271 | int len = strlen(trace_options[i]); | |
1272 | ||
1273 | if (strncmp(cmp, trace_options[i], len) == 0) { | |
1274 | if (neg) | |
1275 | trace_flags &= ~(1 << i); | |
1276 | else | |
1277 | trace_flags |= (1 << i); | |
1278 | break; | |
1279 | } | |
1280 | } | |
1281 | ||
1282 | filp->f_pos += cnt; | |
1283 | ||
1284 | return cnt; | |
1285 | } | |
1286 | ||
1287 | static struct file_operations tracing_iter_fops = { | |
1288 | .open = tracing_open_generic, | |
1289 | .read = tracing_iter_ctrl_read, | |
1290 | .write = tracing_iter_ctrl_write, | |
1291 | }; | |
1292 | ||
1293 | static ssize_t | |
1294 | tracing_ctrl_read(struct file *filp, char __user *ubuf, | |
1295 | size_t cnt, loff_t *ppos) | |
1296 | { | |
1297 | struct trace_array *tr = filp->private_data; | |
1298 | char buf[64]; | |
1299 | int r; | |
1300 | ||
1301 | r = sprintf(buf, "%ld\n", tr->ctrl); | |
1302 | return simple_read_from_buffer(ubuf, cnt, ppos, | |
1303 | buf, r); | |
1304 | } | |
1305 | ||
1306 | static ssize_t | |
1307 | tracing_ctrl_write(struct file *filp, const char __user *ubuf, | |
1308 | size_t cnt, loff_t *ppos) | |
1309 | { | |
1310 | struct trace_array *tr = filp->private_data; | |
1311 | long val; | |
1312 | char buf[64]; | |
1313 | ||
1314 | if (cnt > 63) | |
1315 | cnt = 63; | |
1316 | ||
1317 | if (copy_from_user(&buf, ubuf, cnt)) | |
1318 | return -EFAULT; | |
1319 | ||
1320 | buf[cnt] = 0; | |
1321 | ||
1322 | val = simple_strtoul(buf, NULL, 10); | |
1323 | ||
1324 | val = !!val; | |
1325 | ||
1326 | mutex_lock(&trace_types_lock); | |
1327 | if (tr->ctrl ^ val) { | |
1328 | if (val) | |
1329 | tracer_enabled = 1; | |
1330 | else | |
1331 | tracer_enabled = 0; | |
1332 | ||
1333 | tr->ctrl = val; | |
1334 | ||
1335 | if (current_trace && current_trace->ctrl_update) | |
1336 | current_trace->ctrl_update(tr); | |
1337 | } | |
1338 | mutex_unlock(&trace_types_lock); | |
1339 | ||
1340 | filp->f_pos += cnt; | |
1341 | ||
1342 | return cnt; | |
1343 | } | |
1344 | ||
1345 | static ssize_t | |
1346 | tracing_set_trace_read(struct file *filp, char __user *ubuf, | |
1347 | size_t cnt, loff_t *ppos) | |
1348 | { | |
1349 | char buf[max_tracer_type_len+2]; | |
1350 | int r; | |
1351 | ||
1352 | mutex_lock(&trace_types_lock); | |
1353 | if (current_trace) | |
1354 | r = sprintf(buf, "%s\n", current_trace->name); | |
1355 | else | |
1356 | r = sprintf(buf, "\n"); | |
1357 | mutex_unlock(&trace_types_lock); | |
1358 | ||
1359 | return simple_read_from_buffer(ubuf, cnt, ppos, | |
1360 | buf, r); | |
1361 | } | |
1362 | ||
1363 | static ssize_t | |
1364 | tracing_set_trace_write(struct file *filp, const char __user *ubuf, | |
1365 | size_t cnt, loff_t *ppos) | |
1366 | { | |
1367 | struct trace_array *tr = &global_trace; | |
1368 | struct tracer *t; | |
1369 | char buf[max_tracer_type_len+1]; | |
1370 | int i; | |
1371 | ||
1372 | if (cnt > max_tracer_type_len) | |
1373 | cnt = max_tracer_type_len; | |
1374 | ||
1375 | if (copy_from_user(&buf, ubuf, cnt)) | |
1376 | return -EFAULT; | |
1377 | ||
1378 | buf[cnt] = 0; | |
1379 | ||
1380 | /* strip ending whitespace. */ | |
1381 | for (i = cnt - 1; i > 0 && isspace(buf[i]); i--) | |
1382 | buf[i] = 0; | |
1383 | ||
1384 | mutex_lock(&trace_types_lock); | |
1385 | for (t = trace_types; t; t = t->next) { | |
1386 | if (strcmp(t->name, buf) == 0) | |
1387 | break; | |
1388 | } | |
1389 | if (!t || t == current_trace) | |
1390 | goto out; | |
1391 | ||
1392 | if (current_trace && current_trace->reset) | |
1393 | current_trace->reset(tr); | |
1394 | ||
1395 | current_trace = t; | |
1396 | if (t->init) | |
1397 | t->init(tr); | |
1398 | ||
1399 | out: | |
1400 | mutex_unlock(&trace_types_lock); | |
1401 | ||
1402 | filp->f_pos += cnt; | |
1403 | ||
1404 | return cnt; | |
1405 | } | |
1406 | ||
1407 | static ssize_t | |
1408 | tracing_max_lat_read(struct file *filp, char __user *ubuf, | |
1409 | size_t cnt, loff_t *ppos) | |
1410 | { | |
1411 | unsigned long *ptr = filp->private_data; | |
1412 | char buf[64]; | |
1413 | int r; | |
1414 | ||
1415 | r = snprintf(buf, 64, "%ld\n", | |
1416 | *ptr == (unsigned long)-1 ? -1 : nsecs_to_usecs(*ptr)); | |
1417 | if (r > 64) | |
1418 | r = 64; | |
1419 | return simple_read_from_buffer(ubuf, cnt, ppos, | |
1420 | buf, r); | |
1421 | } | |
1422 | ||
1423 | static ssize_t | |
1424 | tracing_max_lat_write(struct file *filp, const char __user *ubuf, | |
1425 | size_t cnt, loff_t *ppos) | |
1426 | { | |
1427 | long *ptr = filp->private_data; | |
1428 | long val; | |
1429 | char buf[64]; | |
1430 | ||
1431 | if (cnt > 63) | |
1432 | cnt = 63; | |
1433 | ||
1434 | if (copy_from_user(&buf, ubuf, cnt)) | |
1435 | return -EFAULT; | |
1436 | ||
1437 | buf[cnt] = 0; | |
1438 | ||
1439 | val = simple_strtoul(buf, NULL, 10); | |
1440 | ||
1441 | *ptr = val * 1000; | |
1442 | ||
1443 | return cnt; | |
1444 | } | |
1445 | ||
1446 | static struct file_operations tracing_max_lat_fops = { | |
1447 | .open = tracing_open_generic, | |
1448 | .read = tracing_max_lat_read, | |
1449 | .write = tracing_max_lat_write, | |
1450 | }; | |
1451 | ||
1452 | static struct file_operations tracing_ctrl_fops = { | |
1453 | .open = tracing_open_generic, | |
1454 | .read = tracing_ctrl_read, | |
1455 | .write = tracing_ctrl_write, | |
1456 | }; | |
1457 | ||
1458 | static struct file_operations set_tracer_fops = { | |
1459 | .open = tracing_open_generic, | |
1460 | .read = tracing_set_trace_read, | |
1461 | .write = tracing_set_trace_write, | |
1462 | }; | |
1463 | ||
1464 | #ifdef CONFIG_DYNAMIC_FTRACE | |
1465 | ||
1466 | static ssize_t | |
1467 | tracing_read_long(struct file *filp, char __user *ubuf, | |
1468 | size_t cnt, loff_t *ppos) | |
1469 | { | |
1470 | unsigned long *p = filp->private_data; | |
1471 | char buf[64]; | |
1472 | int r; | |
1473 | ||
1474 | r = sprintf(buf, "%ld\n", *p); | |
1475 | return simple_read_from_buffer(ubuf, cnt, ppos, | |
1476 | buf, r); | |
1477 | } | |
1478 | ||
1479 | static struct file_operations tracing_read_long_fops = { | |
1480 | .open = tracing_open_generic, | |
1481 | .read = tracing_read_long, | |
1482 | }; | |
1483 | #endif | |
1484 | ||
1485 | static struct dentry *d_tracer; | |
1486 | ||
1487 | struct dentry *tracing_init_dentry(void) | |
1488 | { | |
1489 | static int once; | |
1490 | ||
1491 | if (d_tracer) | |
1492 | return d_tracer; | |
1493 | ||
1494 | d_tracer = debugfs_create_dir("tracing", NULL); | |
1495 | ||
1496 | if (!d_tracer && !once) { | |
1497 | once = 1; | |
1498 | pr_warning("Could not create debugfs directory 'tracing'\n"); | |
1499 | return NULL; | |
1500 | } | |
1501 | ||
1502 | return d_tracer; | |
1503 | } | |
1504 | ||
60a11774 SR |
1505 | #ifdef CONFIG_FTRACE_SELFTEST |
1506 | /* Let selftest have access to static functions in this file */ | |
1507 | #include "trace_selftest.c" | |
1508 | #endif | |
1509 | ||
bc0c38d1 SR |
1510 | static __init void tracer_init_debugfs(void) |
1511 | { | |
1512 | struct dentry *d_tracer; | |
1513 | struct dentry *entry; | |
1514 | ||
1515 | d_tracer = tracing_init_dentry(); | |
1516 | ||
1517 | entry = debugfs_create_file("tracing_enabled", 0644, d_tracer, | |
1518 | &global_trace, &tracing_ctrl_fops); | |
1519 | if (!entry) | |
1520 | pr_warning("Could not create debugfs 'tracing_enabled' entry\n"); | |
1521 | ||
1522 | entry = debugfs_create_file("iter_ctrl", 0644, d_tracer, | |
1523 | NULL, &tracing_iter_fops); | |
1524 | if (!entry) | |
1525 | pr_warning("Could not create debugfs 'iter_ctrl' entry\n"); | |
1526 | ||
1527 | entry = debugfs_create_file("latency_trace", 0444, d_tracer, | |
1528 | &global_trace, &tracing_lt_fops); | |
1529 | if (!entry) | |
1530 | pr_warning("Could not create debugfs 'latency_trace' entry\n"); | |
1531 | ||
1532 | entry = debugfs_create_file("trace", 0444, d_tracer, | |
1533 | &global_trace, &tracing_fops); | |
1534 | if (!entry) | |
1535 | pr_warning("Could not create debugfs 'trace' entry\n"); | |
1536 | ||
1537 | entry = debugfs_create_file("available_tracers", 0444, d_tracer, | |
1538 | &global_trace, &show_traces_fops); | |
1539 | if (!entry) | |
1540 | pr_warning("Could not create debugfs 'trace' entry\n"); | |
1541 | ||
1542 | entry = debugfs_create_file("current_tracer", 0444, d_tracer, | |
1543 | &global_trace, &set_tracer_fops); | |
1544 | if (!entry) | |
1545 | pr_warning("Could not create debugfs 'trace' entry\n"); | |
1546 | ||
1547 | entry = debugfs_create_file("tracing_max_latency", 0644, d_tracer, | |
1548 | &tracing_max_latency, | |
1549 | &tracing_max_lat_fops); | |
1550 | if (!entry) | |
1551 | pr_warning("Could not create debugfs " | |
1552 | "'tracing_max_latency' entry\n"); | |
1553 | ||
1554 | entry = debugfs_create_file("tracing_thresh", 0644, d_tracer, | |
1555 | &tracing_thresh, &tracing_max_lat_fops); | |
1556 | if (!entry) | |
1557 | pr_warning("Could not create debugfs " | |
1558 | "'tracing_threash' entry\n"); | |
1559 | ||
1560 | #ifdef CONFIG_DYNAMIC_FTRACE | |
1561 | entry = debugfs_create_file("dyn_ftrace_total_info", 0444, d_tracer, | |
1562 | &ftrace_update_tot_cnt, | |
1563 | &tracing_read_long_fops); | |
1564 | if (!entry) | |
1565 | pr_warning("Could not create debugfs " | |
1566 | "'dyn_ftrace_total_info' entry\n"); | |
1567 | #endif | |
1568 | } | |
1569 | ||
1570 | /* dummy trace to disable tracing */ | |
1571 | static struct tracer no_tracer __read_mostly = | |
1572 | { | |
1573 | .name = "none", | |
1574 | }; | |
1575 | ||
4c11d7ae | 1576 | static int trace_alloc_page(void) |
bc0c38d1 | 1577 | { |
4c11d7ae SR |
1578 | struct trace_array_cpu *data; |
1579 | void *array; | |
1580 | struct page *page, *tmp; | |
1581 | LIST_HEAD(pages); | |
1582 | int i; | |
1583 | ||
1584 | /* first allocate a page for each CPU */ | |
1585 | for_each_possible_cpu(i) { | |
1586 | array = (void *)__get_free_page(GFP_KERNEL); | |
1587 | if (array == NULL) { | |
1588 | printk(KERN_ERR "tracer: failed to allocate page" | |
1589 | "for trace buffer!\n"); | |
1590 | goto free_pages; | |
1591 | } | |
1592 | ||
1593 | page = virt_to_page(array); | |
1594 | list_add(&page->lru, &pages); | |
1595 | ||
1596 | /* Only allocate if we are actually using the max trace */ | |
1597 | #ifdef CONFIG_TRACER_MAX_TRACE | |
1598 | array = (void *)__get_free_page(GFP_KERNEL); | |
1599 | if (array == NULL) { | |
1600 | printk(KERN_ERR "tracer: failed to allocate page" | |
1601 | "for trace buffer!\n"); | |
1602 | goto free_pages; | |
1603 | } | |
1604 | page = virt_to_page(array); | |
1605 | list_add(&page->lru, &pages); | |
1606 | #endif | |
1607 | } | |
1608 | ||
1609 | /* Now that we successfully allocate a page per CPU, add them */ | |
1610 | for_each_possible_cpu(i) { | |
1611 | data = global_trace.data[i]; | |
1612 | page = list_entry(pages.next, struct page, lru); | |
1613 | list_del(&page->lru); | |
1614 | list_add_tail(&page->lru, &data->trace_pages); | |
1615 | ClearPageLRU(page); | |
1616 | ||
1617 | #ifdef CONFIG_TRACER_MAX_TRACE | |
1618 | data = max_tr.data[i]; | |
1619 | page = list_entry(pages.next, struct page, lru); | |
1620 | list_del(&page->lru); | |
1621 | list_add_tail(&page->lru, &data->trace_pages); | |
1622 | SetPageLRU(page); | |
1623 | #endif | |
1624 | } | |
1625 | global_trace.entries += ENTRIES_PER_PAGE; | |
1626 | ||
1627 | return 0; | |
1628 | ||
1629 | free_pages: | |
1630 | list_for_each_entry_safe(page, tmp, &pages, lru) { | |
1631 | list_del(&page->lru); | |
1632 | __free_page(page); | |
1633 | } | |
1634 | return -ENOMEM; | |
bc0c38d1 SR |
1635 | } |
1636 | ||
1637 | __init static int tracer_alloc_buffers(void) | |
1638 | { | |
4c11d7ae SR |
1639 | struct trace_array_cpu *data; |
1640 | void *array; | |
1641 | struct page *page; | |
1642 | int pages = 0; | |
60a11774 | 1643 | int ret = -ENOMEM; |
bc0c38d1 SR |
1644 | int i; |
1645 | ||
4c11d7ae | 1646 | /* Allocate the first page for all buffers */ |
bc0c38d1 | 1647 | for_each_possible_cpu(i) { |
4c11d7ae | 1648 | data = global_trace.data[i] = &per_cpu(global_trace_cpu, i); |
bc0c38d1 SR |
1649 | max_tr.data[i] = &per_cpu(max_data, i); |
1650 | ||
4c11d7ae | 1651 | array = (void *)__get_free_page(GFP_KERNEL); |
bc0c38d1 | 1652 | if (array == NULL) { |
4c11d7ae SR |
1653 | printk(KERN_ERR "tracer: failed to allocate page" |
1654 | "for trace buffer!\n"); | |
bc0c38d1 SR |
1655 | goto free_buffers; |
1656 | } | |
4c11d7ae SR |
1657 | data->trace = array; |
1658 | ||
1659 | /* set the array to the list */ | |
1660 | INIT_LIST_HEAD(&data->trace_pages); | |
1661 | page = virt_to_page(array); | |
1662 | list_add(&page->lru, &data->trace_pages); | |
1663 | /* use the LRU flag to differentiate the two buffers */ | |
1664 | ClearPageLRU(page); | |
bc0c38d1 SR |
1665 | |
1666 | /* Only allocate if we are actually using the max trace */ | |
1667 | #ifdef CONFIG_TRACER_MAX_TRACE | |
4c11d7ae | 1668 | array = (void *)__get_free_page(GFP_KERNEL); |
bc0c38d1 | 1669 | if (array == NULL) { |
4c11d7ae SR |
1670 | printk(KERN_ERR "tracer: failed to allocate page" |
1671 | "for trace buffer!\n"); | |
bc0c38d1 SR |
1672 | goto free_buffers; |
1673 | } | |
1674 | max_tr.data[i]->trace = array; | |
4c11d7ae SR |
1675 | |
1676 | INIT_LIST_HEAD(&max_tr.data[i]->trace_pages); | |
1677 | page = virt_to_page(array); | |
1678 | list_add(&page->lru, &max_tr.data[i]->trace_pages); | |
1679 | SetPageLRU(page); | |
bc0c38d1 SR |
1680 | #endif |
1681 | } | |
1682 | ||
1683 | /* | |
1684 | * Since we allocate by orders of pages, we may be able to | |
1685 | * round up a bit. | |
1686 | */ | |
4c11d7ae | 1687 | global_trace.entries = ENTRIES_PER_PAGE; |
4c11d7ae SR |
1688 | pages++; |
1689 | ||
1690 | while (global_trace.entries < trace_nr_entries) { | |
1691 | if (trace_alloc_page()) | |
1692 | break; | |
1693 | pages++; | |
1694 | } | |
89b2f978 | 1695 | max_tr.entries = global_trace.entries; |
bc0c38d1 | 1696 | |
4c11d7ae SR |
1697 | pr_info("tracer: %d pages allocated for %ld", |
1698 | pages, trace_nr_entries); | |
bc0c38d1 SR |
1699 | pr_info(" entries of %ld bytes\n", (long)TRACE_ENTRY_SIZE); |
1700 | pr_info(" actual entries %ld\n", global_trace.entries); | |
1701 | ||
1702 | tracer_init_debugfs(); | |
1703 | ||
1704 | trace_init_cmdlines(); | |
1705 | ||
1706 | register_tracer(&no_tracer); | |
1707 | current_trace = &no_tracer; | |
1708 | ||
60a11774 SR |
1709 | /* All seems OK, enable tracing */ |
1710 | tracing_disabled = 0; | |
1711 | ||
bc0c38d1 SR |
1712 | return 0; |
1713 | ||
1714 | free_buffers: | |
1715 | for (i-- ; i >= 0; i--) { | |
4c11d7ae | 1716 | struct page *page, *tmp; |
bc0c38d1 SR |
1717 | struct trace_array_cpu *data = global_trace.data[i]; |
1718 | ||
1719 | if (data && data->trace) { | |
4c11d7ae SR |
1720 | list_for_each_entry_safe(page, tmp, |
1721 | &data->trace_pages, lru) { | |
1722 | list_del(&page->lru); | |
1723 | __free_page(page); | |
1724 | } | |
bc0c38d1 SR |
1725 | data->trace = NULL; |
1726 | } | |
1727 | ||
1728 | #ifdef CONFIG_TRACER_MAX_TRACE | |
1729 | data = max_tr.data[i]; | |
1730 | if (data && data->trace) { | |
4c11d7ae SR |
1731 | list_for_each_entry_safe(page, tmp, |
1732 | &data->trace_pages, lru) { | |
1733 | list_del(&page->lru); | |
1734 | __free_page(page); | |
1735 | } | |
bc0c38d1 SR |
1736 | data->trace = NULL; |
1737 | } | |
1738 | #endif | |
1739 | } | |
60a11774 | 1740 | return ret; |
bc0c38d1 SR |
1741 | } |
1742 | ||
60a11774 | 1743 | fs_initcall(tracer_alloc_buffers); |