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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> | |
2a2cc8f7 | 27 | #include <linux/poll.h> |
bc0c38d1 SR |
28 | #include <linux/gfp.h> |
29 | #include <linux/fs.h> | |
30 | ||
86387f7e IM |
31 | #include <linux/stacktrace.h> |
32 | ||
bc0c38d1 SR |
33 | #include "trace.h" |
34 | ||
35 | unsigned long __read_mostly tracing_max_latency = (cycle_t)ULONG_MAX; | |
36 | unsigned long __read_mostly tracing_thresh; | |
37 | ||
a98a3c3f | 38 | /* dummy trace to disable tracing */ |
cffae437 | 39 | static struct tracer no_tracer __read_mostly = { |
a98a3c3f SR |
40 | .name = "none", |
41 | }; | |
42 | ||
43 | static int trace_alloc_page(void); | |
44 | static int trace_free_page(void); | |
45 | ||
60a11774 SR |
46 | static int tracing_disabled = 1; |
47 | ||
72829bc3 | 48 | long |
bc0c38d1 SR |
49 | ns2usecs(cycle_t nsec) |
50 | { | |
51 | nsec += 500; | |
52 | do_div(nsec, 1000); | |
53 | return nsec; | |
54 | } | |
55 | ||
e309b41d | 56 | cycle_t ftrace_now(int cpu) |
750ed1a4 | 57 | { |
0fd9e0da | 58 | return cpu_clock(cpu); |
750ed1a4 IM |
59 | } |
60 | ||
bc0c38d1 SR |
61 | static struct trace_array global_trace; |
62 | ||
63 | static DEFINE_PER_CPU(struct trace_array_cpu, global_trace_cpu); | |
64 | ||
65 | static struct trace_array max_tr; | |
66 | ||
67 | static DEFINE_PER_CPU(struct trace_array_cpu, max_data); | |
68 | ||
26994ead | 69 | static int tracer_enabled = 1; |
57422797 | 70 | static unsigned long trace_nr_entries = 65536UL; |
bc0c38d1 SR |
71 | |
72 | static struct tracer *trace_types __read_mostly; | |
73 | static struct tracer *current_trace __read_mostly; | |
74 | static int max_tracer_type_len; | |
75 | ||
76 | static DEFINE_MUTEX(trace_types_lock); | |
4e655519 IM |
77 | static DECLARE_WAIT_QUEUE_HEAD(trace_wait); |
78 | ||
79 | unsigned long trace_flags = TRACE_ITER_PRINT_PARENT; | |
80 | ||
4e655519 IM |
81 | void trace_wake_up(void) |
82 | { | |
017730c1 IM |
83 | /* |
84 | * The runqueue_is_locked() can fail, but this is the best we | |
85 | * have for now: | |
86 | */ | |
87 | if (!(trace_flags & TRACE_ITER_BLOCK) && !runqueue_is_locked()) | |
4e655519 IM |
88 | wake_up(&trace_wait); |
89 | } | |
bc0c38d1 | 90 | |
4c11d7ae SR |
91 | #define ENTRIES_PER_PAGE (PAGE_SIZE / sizeof(struct trace_entry)) |
92 | ||
bc0c38d1 SR |
93 | static int __init set_nr_entries(char *str) |
94 | { | |
95 | if (!str) | |
96 | return 0; | |
97 | trace_nr_entries = simple_strtoul(str, &str, 0); | |
98 | return 1; | |
99 | } | |
100 | __setup("trace_entries=", set_nr_entries); | |
101 | ||
57f50be1 SR |
102 | unsigned long nsecs_to_usecs(unsigned long nsecs) |
103 | { | |
104 | return nsecs / 1000; | |
105 | } | |
106 | ||
bc0c38d1 SR |
107 | enum trace_flag_type { |
108 | TRACE_FLAG_IRQS_OFF = 0x01, | |
109 | TRACE_FLAG_NEED_RESCHED = 0x02, | |
110 | TRACE_FLAG_HARDIRQ = 0x04, | |
111 | TRACE_FLAG_SOFTIRQ = 0x08, | |
112 | }; | |
113 | ||
bc0c38d1 SR |
114 | #define TRACE_ITER_SYM_MASK \ |
115 | (TRACE_ITER_PRINT_PARENT|TRACE_ITER_SYM_OFFSET|TRACE_ITER_SYM_ADDR) | |
116 | ||
117 | /* These must match the bit postions above */ | |
118 | static const char *trace_options[] = { | |
119 | "print-parent", | |
120 | "sym-offset", | |
121 | "sym-addr", | |
122 | "verbose", | |
f9896bf3 | 123 | "raw", |
5e3ca0ec | 124 | "hex", |
cb0f12aa | 125 | "bin", |
2a2cc8f7 | 126 | "block", |
86387f7e | 127 | "stacktrace", |
4ac3ba41 | 128 | "sched-tree", |
bc0c38d1 SR |
129 | NULL |
130 | }; | |
131 | ||
92205c23 SR |
132 | static raw_spinlock_t ftrace_max_lock = |
133 | (raw_spinlock_t)__RAW_SPIN_LOCK_UNLOCKED; | |
bc0c38d1 SR |
134 | |
135 | /* | |
136 | * Copy the new maximum trace into the separate maximum-trace | |
137 | * structure. (this way the maximum trace is permanently saved, | |
138 | * for later retrieval via /debugfs/tracing/latency_trace) | |
139 | */ | |
e309b41d | 140 | static void |
bc0c38d1 SR |
141 | __update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) |
142 | { | |
143 | struct trace_array_cpu *data = tr->data[cpu]; | |
144 | ||
145 | max_tr.cpu = cpu; | |
146 | max_tr.time_start = data->preempt_timestamp; | |
147 | ||
148 | data = max_tr.data[cpu]; | |
149 | data->saved_latency = tracing_max_latency; | |
150 | ||
151 | memcpy(data->comm, tsk->comm, TASK_COMM_LEN); | |
152 | data->pid = tsk->pid; | |
153 | data->uid = tsk->uid; | |
154 | data->nice = tsk->static_prio - 20 - MAX_RT_PRIO; | |
155 | data->policy = tsk->policy; | |
156 | data->rt_priority = tsk->rt_priority; | |
157 | ||
158 | /* record this tasks comm */ | |
159 | tracing_record_cmdline(current); | |
160 | } | |
161 | ||
c7aafc54 IM |
162 | void check_pages(struct trace_array_cpu *data) |
163 | { | |
164 | struct page *page, *tmp; | |
165 | ||
166 | BUG_ON(data->trace_pages.next->prev != &data->trace_pages); | |
167 | BUG_ON(data->trace_pages.prev->next != &data->trace_pages); | |
168 | ||
169 | list_for_each_entry_safe(page, tmp, &data->trace_pages, lru) { | |
170 | BUG_ON(page->lru.next->prev != &page->lru); | |
171 | BUG_ON(page->lru.prev->next != &page->lru); | |
172 | } | |
173 | } | |
174 | ||
175 | void *head_page(struct trace_array_cpu *data) | |
176 | { | |
177 | struct page *page; | |
178 | ||
179 | check_pages(data); | |
180 | if (list_empty(&data->trace_pages)) | |
181 | return NULL; | |
182 | ||
183 | page = list_entry(data->trace_pages.next, struct page, lru); | |
184 | BUG_ON(&page->lru == &data->trace_pages); | |
185 | ||
186 | return page_address(page); | |
187 | } | |
188 | ||
72829bc3 | 189 | int |
214023c3 SR |
190 | trace_seq_printf(struct trace_seq *s, const char *fmt, ...) |
191 | { | |
192 | int len = (PAGE_SIZE - 1) - s->len; | |
193 | va_list ap; | |
b3806b43 | 194 | int ret; |
214023c3 SR |
195 | |
196 | if (!len) | |
197 | return 0; | |
198 | ||
199 | va_start(ap, fmt); | |
b3806b43 | 200 | ret = vsnprintf(s->buffer + s->len, len, fmt, ap); |
214023c3 SR |
201 | va_end(ap); |
202 | ||
b3806b43 | 203 | /* If we can't write it all, don't bother writing anything */ |
72829bc3 | 204 | if (ret >= len) |
b3806b43 SR |
205 | return 0; |
206 | ||
207 | s->len += ret; | |
214023c3 SR |
208 | |
209 | return len; | |
210 | } | |
211 | ||
e309b41d | 212 | static int |
214023c3 SR |
213 | trace_seq_puts(struct trace_seq *s, const char *str) |
214 | { | |
215 | int len = strlen(str); | |
216 | ||
217 | if (len > ((PAGE_SIZE - 1) - s->len)) | |
b3806b43 | 218 | return 0; |
214023c3 SR |
219 | |
220 | memcpy(s->buffer + s->len, str, len); | |
221 | s->len += len; | |
222 | ||
223 | return len; | |
224 | } | |
225 | ||
e309b41d | 226 | static int |
214023c3 SR |
227 | trace_seq_putc(struct trace_seq *s, unsigned char c) |
228 | { | |
229 | if (s->len >= (PAGE_SIZE - 1)) | |
230 | return 0; | |
231 | ||
232 | s->buffer[s->len++] = c; | |
233 | ||
234 | return 1; | |
235 | } | |
236 | ||
e309b41d | 237 | static int |
cb0f12aa IM |
238 | trace_seq_putmem(struct trace_seq *s, void *mem, size_t len) |
239 | { | |
240 | if (len > ((PAGE_SIZE - 1) - s->len)) | |
241 | return 0; | |
242 | ||
243 | memcpy(s->buffer + s->len, mem, len); | |
244 | s->len += len; | |
245 | ||
246 | return len; | |
247 | } | |
248 | ||
5e3ca0ec | 249 | #define HEX_CHARS 17 |
93dcc6ea | 250 | static const char hex2asc[] = "0123456789abcdef"; |
5e3ca0ec | 251 | |
e309b41d | 252 | static int |
5e3ca0ec IM |
253 | trace_seq_putmem_hex(struct trace_seq *s, void *mem, size_t len) |
254 | { | |
255 | unsigned char hex[HEX_CHARS]; | |
93dcc6ea | 256 | unsigned char *data = mem; |
5e3ca0ec IM |
257 | unsigned char byte; |
258 | int i, j; | |
259 | ||
260 | BUG_ON(len >= HEX_CHARS); | |
261 | ||
5e3ca0ec IM |
262 | #ifdef __BIG_ENDIAN |
263 | for (i = 0, j = 0; i < len; i++) { | |
264 | #else | |
265 | for (i = len-1, j = 0; i >= 0; i--) { | |
266 | #endif | |
267 | byte = data[i]; | |
268 | ||
93dcc6ea TG |
269 | hex[j++] = hex2asc[byte & 0x0f]; |
270 | hex[j++] = hex2asc[byte >> 4]; | |
5e3ca0ec | 271 | } |
93dcc6ea | 272 | hex[j++] = ' '; |
5e3ca0ec IM |
273 | |
274 | return trace_seq_putmem(s, hex, j); | |
275 | } | |
276 | ||
e309b41d | 277 | static void |
214023c3 SR |
278 | trace_seq_reset(struct trace_seq *s) |
279 | { | |
280 | s->len = 0; | |
281 | } | |
282 | ||
e309b41d | 283 | static void |
214023c3 SR |
284 | trace_print_seq(struct seq_file *m, struct trace_seq *s) |
285 | { | |
286 | int len = s->len >= PAGE_SIZE ? PAGE_SIZE - 1 : s->len; | |
287 | ||
288 | s->buffer[len] = 0; | |
289 | seq_puts(m, s->buffer); | |
290 | ||
291 | trace_seq_reset(s); | |
292 | } | |
293 | ||
e309b41d | 294 | static void |
c7aafc54 IM |
295 | flip_trace(struct trace_array_cpu *tr1, struct trace_array_cpu *tr2) |
296 | { | |
297 | struct list_head flip_pages; | |
298 | ||
299 | INIT_LIST_HEAD(&flip_pages); | |
300 | ||
93a588f4 | 301 | memcpy(&tr1->trace_head_idx, &tr2->trace_head_idx, |
c7aafc54 | 302 | sizeof(struct trace_array_cpu) - |
93a588f4 | 303 | offsetof(struct trace_array_cpu, trace_head_idx)); |
c7aafc54 IM |
304 | |
305 | check_pages(tr1); | |
306 | check_pages(tr2); | |
307 | list_splice_init(&tr1->trace_pages, &flip_pages); | |
308 | list_splice_init(&tr2->trace_pages, &tr1->trace_pages); | |
309 | list_splice_init(&flip_pages, &tr2->trace_pages); | |
310 | BUG_ON(!list_empty(&flip_pages)); | |
311 | check_pages(tr1); | |
312 | check_pages(tr2); | |
313 | } | |
314 | ||
e309b41d | 315 | void |
bc0c38d1 SR |
316 | update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) |
317 | { | |
318 | struct trace_array_cpu *data; | |
bc0c38d1 SR |
319 | int i; |
320 | ||
4c11d7ae | 321 | WARN_ON_ONCE(!irqs_disabled()); |
92205c23 | 322 | __raw_spin_lock(&ftrace_max_lock); |
bc0c38d1 SR |
323 | /* clear out all the previous traces */ |
324 | for_each_possible_cpu(i) { | |
325 | data = tr->data[i]; | |
c7aafc54 | 326 | flip_trace(max_tr.data[i], data); |
89b2f978 | 327 | tracing_reset(data); |
bc0c38d1 SR |
328 | } |
329 | ||
330 | __update_max_tr(tr, tsk, cpu); | |
92205c23 | 331 | __raw_spin_unlock(&ftrace_max_lock); |
bc0c38d1 SR |
332 | } |
333 | ||
334 | /** | |
335 | * update_max_tr_single - only copy one trace over, and reset the rest | |
336 | * @tr - tracer | |
337 | * @tsk - task with the latency | |
338 | * @cpu - the cpu of the buffer to copy. | |
339 | */ | |
e309b41d | 340 | void |
bc0c38d1 SR |
341 | update_max_tr_single(struct trace_array *tr, struct task_struct *tsk, int cpu) |
342 | { | |
343 | struct trace_array_cpu *data = tr->data[cpu]; | |
bc0c38d1 SR |
344 | int i; |
345 | ||
4c11d7ae | 346 | WARN_ON_ONCE(!irqs_disabled()); |
92205c23 | 347 | __raw_spin_lock(&ftrace_max_lock); |
bc0c38d1 SR |
348 | for_each_possible_cpu(i) |
349 | tracing_reset(max_tr.data[i]); | |
350 | ||
c7aafc54 | 351 | flip_trace(max_tr.data[cpu], data); |
89b2f978 | 352 | tracing_reset(data); |
bc0c38d1 SR |
353 | |
354 | __update_max_tr(tr, tsk, cpu); | |
92205c23 | 355 | __raw_spin_unlock(&ftrace_max_lock); |
bc0c38d1 SR |
356 | } |
357 | ||
358 | int register_tracer(struct tracer *type) | |
359 | { | |
360 | struct tracer *t; | |
361 | int len; | |
362 | int ret = 0; | |
363 | ||
364 | if (!type->name) { | |
365 | pr_info("Tracer must have a name\n"); | |
366 | return -1; | |
367 | } | |
368 | ||
369 | mutex_lock(&trace_types_lock); | |
370 | for (t = trace_types; t; t = t->next) { | |
371 | if (strcmp(type->name, t->name) == 0) { | |
372 | /* already found */ | |
373 | pr_info("Trace %s already registered\n", | |
374 | type->name); | |
375 | ret = -1; | |
376 | goto out; | |
377 | } | |
378 | } | |
379 | ||
60a11774 SR |
380 | #ifdef CONFIG_FTRACE_STARTUP_TEST |
381 | if (type->selftest) { | |
382 | struct tracer *saved_tracer = current_trace; | |
383 | struct trace_array_cpu *data; | |
384 | struct trace_array *tr = &global_trace; | |
385 | int saved_ctrl = tr->ctrl; | |
386 | int i; | |
387 | /* | |
388 | * Run a selftest on this tracer. | |
389 | * Here we reset the trace buffer, and set the current | |
390 | * tracer to be this tracer. The tracer can then run some | |
391 | * internal tracing to verify that everything is in order. | |
392 | * If we fail, we do not register this tracer. | |
393 | */ | |
394 | for_each_possible_cpu(i) { | |
60a11774 | 395 | data = tr->data[i]; |
c7aafc54 IM |
396 | if (!head_page(data)) |
397 | continue; | |
60a11774 SR |
398 | tracing_reset(data); |
399 | } | |
400 | current_trace = type; | |
401 | tr->ctrl = 0; | |
402 | /* the test is responsible for initializing and enabling */ | |
403 | pr_info("Testing tracer %s: ", type->name); | |
404 | ret = type->selftest(type, tr); | |
405 | /* the test is responsible for resetting too */ | |
406 | current_trace = saved_tracer; | |
407 | tr->ctrl = saved_ctrl; | |
408 | if (ret) { | |
409 | printk(KERN_CONT "FAILED!\n"); | |
410 | goto out; | |
411 | } | |
1d4db00a SR |
412 | /* Only reset on passing, to avoid touching corrupted buffers */ |
413 | for_each_possible_cpu(i) { | |
414 | data = tr->data[i]; | |
415 | if (!head_page(data)) | |
416 | continue; | |
417 | tracing_reset(data); | |
418 | } | |
60a11774 SR |
419 | printk(KERN_CONT "PASSED\n"); |
420 | } | |
421 | #endif | |
422 | ||
bc0c38d1 SR |
423 | type->next = trace_types; |
424 | trace_types = type; | |
425 | len = strlen(type->name); | |
426 | if (len > max_tracer_type_len) | |
427 | max_tracer_type_len = len; | |
60a11774 | 428 | |
bc0c38d1 SR |
429 | out: |
430 | mutex_unlock(&trace_types_lock); | |
431 | ||
432 | return ret; | |
433 | } | |
434 | ||
435 | void unregister_tracer(struct tracer *type) | |
436 | { | |
437 | struct tracer **t; | |
438 | int len; | |
439 | ||
440 | mutex_lock(&trace_types_lock); | |
441 | for (t = &trace_types; *t; t = &(*t)->next) { | |
442 | if (*t == type) | |
443 | goto found; | |
444 | } | |
445 | pr_info("Trace %s not registered\n", type->name); | |
446 | goto out; | |
447 | ||
448 | found: | |
449 | *t = (*t)->next; | |
450 | if (strlen(type->name) != max_tracer_type_len) | |
451 | goto out; | |
452 | ||
453 | max_tracer_type_len = 0; | |
454 | for (t = &trace_types; *t; t = &(*t)->next) { | |
455 | len = strlen((*t)->name); | |
456 | if (len > max_tracer_type_len) | |
457 | max_tracer_type_len = len; | |
458 | } | |
459 | out: | |
460 | mutex_unlock(&trace_types_lock); | |
461 | } | |
462 | ||
e309b41d | 463 | void tracing_reset(struct trace_array_cpu *data) |
bc0c38d1 SR |
464 | { |
465 | data->trace_idx = 0; | |
93a588f4 SR |
466 | data->trace_head = data->trace_tail = head_page(data); |
467 | data->trace_head_idx = 0; | |
468 | data->trace_tail_idx = 0; | |
bc0c38d1 SR |
469 | } |
470 | ||
bc0c38d1 SR |
471 | #define SAVED_CMDLINES 128 |
472 | static unsigned map_pid_to_cmdline[PID_MAX_DEFAULT+1]; | |
473 | static unsigned map_cmdline_to_pid[SAVED_CMDLINES]; | |
474 | static char saved_cmdlines[SAVED_CMDLINES][TASK_COMM_LEN]; | |
475 | static int cmdline_idx; | |
476 | static DEFINE_SPINLOCK(trace_cmdline_lock); | |
477 | atomic_t trace_record_cmdline_disabled; | |
478 | ||
479 | static void trace_init_cmdlines(void) | |
480 | { | |
481 | memset(&map_pid_to_cmdline, -1, sizeof(map_pid_to_cmdline)); | |
482 | memset(&map_cmdline_to_pid, -1, sizeof(map_cmdline_to_pid)); | |
483 | cmdline_idx = 0; | |
484 | } | |
485 | ||
e309b41d | 486 | void trace_stop_cmdline_recording(void); |
bc0c38d1 | 487 | |
e309b41d | 488 | static void trace_save_cmdline(struct task_struct *tsk) |
bc0c38d1 SR |
489 | { |
490 | unsigned map; | |
491 | unsigned idx; | |
492 | ||
493 | if (!tsk->pid || unlikely(tsk->pid > PID_MAX_DEFAULT)) | |
494 | return; | |
495 | ||
496 | /* | |
497 | * It's not the end of the world if we don't get | |
498 | * the lock, but we also don't want to spin | |
499 | * nor do we want to disable interrupts, | |
500 | * so if we miss here, then better luck next time. | |
501 | */ | |
502 | if (!spin_trylock(&trace_cmdline_lock)) | |
503 | return; | |
504 | ||
505 | idx = map_pid_to_cmdline[tsk->pid]; | |
506 | if (idx >= SAVED_CMDLINES) { | |
507 | idx = (cmdline_idx + 1) % SAVED_CMDLINES; | |
508 | ||
509 | map = map_cmdline_to_pid[idx]; | |
510 | if (map <= PID_MAX_DEFAULT) | |
511 | map_pid_to_cmdline[map] = (unsigned)-1; | |
512 | ||
513 | map_pid_to_cmdline[tsk->pid] = idx; | |
514 | ||
515 | cmdline_idx = idx; | |
516 | } | |
517 | ||
518 | memcpy(&saved_cmdlines[idx], tsk->comm, TASK_COMM_LEN); | |
519 | ||
520 | spin_unlock(&trace_cmdline_lock); | |
521 | } | |
522 | ||
e309b41d | 523 | static char *trace_find_cmdline(int pid) |
bc0c38d1 SR |
524 | { |
525 | char *cmdline = "<...>"; | |
526 | unsigned map; | |
527 | ||
528 | if (!pid) | |
529 | return "<idle>"; | |
530 | ||
531 | if (pid > PID_MAX_DEFAULT) | |
532 | goto out; | |
533 | ||
534 | map = map_pid_to_cmdline[pid]; | |
535 | if (map >= SAVED_CMDLINES) | |
536 | goto out; | |
537 | ||
538 | cmdline = saved_cmdlines[map]; | |
539 | ||
540 | out: | |
541 | return cmdline; | |
542 | } | |
543 | ||
e309b41d | 544 | void tracing_record_cmdline(struct task_struct *tsk) |
bc0c38d1 SR |
545 | { |
546 | if (atomic_read(&trace_record_cmdline_disabled)) | |
547 | return; | |
548 | ||
549 | trace_save_cmdline(tsk); | |
550 | } | |
551 | ||
e309b41d | 552 | static inline struct list_head * |
93a588f4 SR |
553 | trace_next_list(struct trace_array_cpu *data, struct list_head *next) |
554 | { | |
555 | /* | |
556 | * Roundrobin - but skip the head (which is not a real page): | |
557 | */ | |
558 | next = next->next; | |
559 | if (unlikely(next == &data->trace_pages)) | |
560 | next = next->next; | |
561 | BUG_ON(next == &data->trace_pages); | |
562 | ||
563 | return next; | |
564 | } | |
565 | ||
e309b41d | 566 | static inline void * |
93a588f4 SR |
567 | trace_next_page(struct trace_array_cpu *data, void *addr) |
568 | { | |
569 | struct list_head *next; | |
570 | struct page *page; | |
571 | ||
572 | page = virt_to_page(addr); | |
573 | ||
574 | next = trace_next_list(data, &page->lru); | |
575 | page = list_entry(next, struct page, lru); | |
576 | ||
577 | return page_address(page); | |
578 | } | |
579 | ||
e309b41d | 580 | static inline struct trace_entry * |
c7aafc54 | 581 | tracing_get_trace_entry(struct trace_array *tr, struct trace_array_cpu *data) |
bc0c38d1 SR |
582 | { |
583 | unsigned long idx, idx_next; | |
584 | struct trace_entry *entry; | |
585 | ||
4c11d7ae | 586 | data->trace_idx++; |
93a588f4 | 587 | idx = data->trace_head_idx; |
bc0c38d1 SR |
588 | idx_next = idx + 1; |
589 | ||
c7aafc54 IM |
590 | BUG_ON(idx * TRACE_ENTRY_SIZE >= PAGE_SIZE); |
591 | ||
93a588f4 | 592 | entry = data->trace_head + idx * TRACE_ENTRY_SIZE; |
4c11d7ae SR |
593 | |
594 | if (unlikely(idx_next >= ENTRIES_PER_PAGE)) { | |
93a588f4 | 595 | data->trace_head = trace_next_page(data, data->trace_head); |
bc0c38d1 SR |
596 | idx_next = 0; |
597 | } | |
598 | ||
93a588f4 SR |
599 | if (data->trace_head == data->trace_tail && |
600 | idx_next == data->trace_tail_idx) { | |
601 | /* overrun */ | |
602 | data->trace_tail_idx++; | |
603 | if (data->trace_tail_idx >= ENTRIES_PER_PAGE) { | |
604 | data->trace_tail = | |
605 | trace_next_page(data, data->trace_tail); | |
606 | data->trace_tail_idx = 0; | |
607 | } | |
608 | } | |
609 | ||
610 | data->trace_head_idx = idx_next; | |
bc0c38d1 SR |
611 | |
612 | return entry; | |
613 | } | |
614 | ||
e309b41d | 615 | static inline void |
c7aafc54 | 616 | tracing_generic_entry_update(struct trace_entry *entry, unsigned long flags) |
bc0c38d1 SR |
617 | { |
618 | struct task_struct *tsk = current; | |
619 | unsigned long pc; | |
620 | ||
621 | pc = preempt_count(); | |
622 | ||
c7aafc54 | 623 | entry->preempt_count = pc & 0xff; |
72829bc3 | 624 | entry->pid = (tsk) ? tsk->pid : 0; |
750ed1a4 | 625 | entry->t = ftrace_now(raw_smp_processor_id()); |
bc0c38d1 SR |
626 | entry->flags = (irqs_disabled_flags(flags) ? TRACE_FLAG_IRQS_OFF : 0) | |
627 | ((pc & HARDIRQ_MASK) ? TRACE_FLAG_HARDIRQ : 0) | | |
628 | ((pc & SOFTIRQ_MASK) ? TRACE_FLAG_SOFTIRQ : 0) | | |
629 | (need_resched() ? TRACE_FLAG_NEED_RESCHED : 0); | |
630 | } | |
631 | ||
e309b41d | 632 | void |
6fb44b71 SR |
633 | trace_function(struct trace_array *tr, struct trace_array_cpu *data, |
634 | unsigned long ip, unsigned long parent_ip, unsigned long flags) | |
bc0c38d1 SR |
635 | { |
636 | struct trace_entry *entry; | |
dcb6308f | 637 | unsigned long irq_flags; |
bc0c38d1 | 638 | |
92205c23 SR |
639 | raw_local_irq_save(irq_flags); |
640 | __raw_spin_lock(&data->lock); | |
c7aafc54 | 641 | entry = tracing_get_trace_entry(tr, data); |
bc0c38d1 | 642 | tracing_generic_entry_update(entry, flags); |
c7aafc54 IM |
643 | entry->type = TRACE_FN; |
644 | entry->fn.ip = ip; | |
645 | entry->fn.parent_ip = parent_ip; | |
92205c23 SR |
646 | __raw_spin_unlock(&data->lock); |
647 | raw_local_irq_restore(irq_flags); | |
bc0c38d1 SR |
648 | } |
649 | ||
e309b41d | 650 | void |
2e0f5761 IM |
651 | ftrace(struct trace_array *tr, struct trace_array_cpu *data, |
652 | unsigned long ip, unsigned long parent_ip, unsigned long flags) | |
653 | { | |
654 | if (likely(!atomic_read(&data->disabled))) | |
6fb44b71 | 655 | trace_function(tr, data, ip, parent_ip, flags); |
2e0f5761 IM |
656 | } |
657 | ||
e309b41d | 658 | void |
4e655519 IM |
659 | __trace_special(void *__tr, void *__data, |
660 | unsigned long arg1, unsigned long arg2, unsigned long arg3) | |
f0a920d5 | 661 | { |
4e655519 IM |
662 | struct trace_array_cpu *data = __data; |
663 | struct trace_array *tr = __tr; | |
f0a920d5 | 664 | struct trace_entry *entry; |
dcb6308f | 665 | unsigned long irq_flags; |
f0a920d5 | 666 | |
92205c23 SR |
667 | raw_local_irq_save(irq_flags); |
668 | __raw_spin_lock(&data->lock); | |
f0a920d5 IM |
669 | entry = tracing_get_trace_entry(tr, data); |
670 | tracing_generic_entry_update(entry, 0); | |
671 | entry->type = TRACE_SPECIAL; | |
672 | entry->special.arg1 = arg1; | |
673 | entry->special.arg2 = arg2; | |
674 | entry->special.arg3 = arg3; | |
92205c23 SR |
675 | __raw_spin_unlock(&data->lock); |
676 | raw_local_irq_restore(irq_flags); | |
017730c1 IM |
677 | |
678 | trace_wake_up(); | |
86387f7e IM |
679 | } |
680 | ||
681 | void __trace_stack(struct trace_array *tr, | |
682 | struct trace_array_cpu *data, | |
683 | unsigned long flags, | |
684 | int skip) | |
685 | { | |
686 | struct trace_entry *entry; | |
687 | struct stack_trace trace; | |
688 | ||
689 | if (!(trace_flags & TRACE_ITER_STACKTRACE)) | |
690 | return; | |
691 | ||
692 | entry = tracing_get_trace_entry(tr, data); | |
693 | tracing_generic_entry_update(entry, flags); | |
694 | entry->type = TRACE_STACK; | |
695 | ||
696 | memset(&entry->stack, 0, sizeof(entry->stack)); | |
697 | ||
698 | trace.nr_entries = 0; | |
699 | trace.max_entries = FTRACE_STACK_ENTRIES; | |
700 | trace.skip = skip; | |
701 | trace.entries = entry->stack.caller; | |
702 | ||
703 | save_stack_trace(&trace); | |
f0a920d5 IM |
704 | } |
705 | ||
e309b41d | 706 | void |
bc0c38d1 SR |
707 | tracing_sched_switch_trace(struct trace_array *tr, |
708 | struct trace_array_cpu *data, | |
86387f7e IM |
709 | struct task_struct *prev, |
710 | struct task_struct *next, | |
bc0c38d1 SR |
711 | unsigned long flags) |
712 | { | |
713 | struct trace_entry *entry; | |
dcb6308f | 714 | unsigned long irq_flags; |
bc0c38d1 | 715 | |
92205c23 SR |
716 | raw_local_irq_save(irq_flags); |
717 | __raw_spin_lock(&data->lock); | |
c7aafc54 | 718 | entry = tracing_get_trace_entry(tr, data); |
bc0c38d1 SR |
719 | tracing_generic_entry_update(entry, flags); |
720 | entry->type = TRACE_CTX; | |
721 | entry->ctx.prev_pid = prev->pid; | |
722 | entry->ctx.prev_prio = prev->prio; | |
723 | entry->ctx.prev_state = prev->state; | |
724 | entry->ctx.next_pid = next->pid; | |
725 | entry->ctx.next_prio = next->prio; | |
bac524d3 | 726 | entry->ctx.next_state = next->state; |
86387f7e | 727 | __trace_stack(tr, data, flags, 4); |
92205c23 SR |
728 | __raw_spin_unlock(&data->lock); |
729 | raw_local_irq_restore(irq_flags); | |
bc0c38d1 SR |
730 | } |
731 | ||
57422797 IM |
732 | void |
733 | tracing_sched_wakeup_trace(struct trace_array *tr, | |
734 | struct trace_array_cpu *data, | |
86387f7e IM |
735 | struct task_struct *wakee, |
736 | struct task_struct *curr, | |
57422797 IM |
737 | unsigned long flags) |
738 | { | |
739 | struct trace_entry *entry; | |
740 | unsigned long irq_flags; | |
741 | ||
92205c23 SR |
742 | raw_local_irq_save(irq_flags); |
743 | __raw_spin_lock(&data->lock); | |
57422797 IM |
744 | entry = tracing_get_trace_entry(tr, data); |
745 | tracing_generic_entry_update(entry, flags); | |
746 | entry->type = TRACE_WAKE; | |
747 | entry->ctx.prev_pid = curr->pid; | |
748 | entry->ctx.prev_prio = curr->prio; | |
749 | entry->ctx.prev_state = curr->state; | |
750 | entry->ctx.next_pid = wakee->pid; | |
751 | entry->ctx.next_prio = wakee->prio; | |
bac524d3 | 752 | entry->ctx.next_state = wakee->state; |
86387f7e | 753 | __trace_stack(tr, data, flags, 5); |
92205c23 SR |
754 | __raw_spin_unlock(&data->lock); |
755 | raw_local_irq_restore(irq_flags); | |
017730c1 IM |
756 | |
757 | trace_wake_up(); | |
57422797 IM |
758 | } |
759 | ||
2e0f5761 | 760 | #ifdef CONFIG_FTRACE |
e309b41d | 761 | static void |
2e0f5761 IM |
762 | function_trace_call(unsigned long ip, unsigned long parent_ip) |
763 | { | |
764 | struct trace_array *tr = &global_trace; | |
765 | struct trace_array_cpu *data; | |
766 | unsigned long flags; | |
767 | long disabled; | |
768 | int cpu; | |
769 | ||
770 | if (unlikely(!tracer_enabled)) | |
771 | return; | |
772 | ||
773 | local_irq_save(flags); | |
774 | cpu = raw_smp_processor_id(); | |
775 | data = tr->data[cpu]; | |
776 | disabled = atomic_inc_return(&data->disabled); | |
777 | ||
778 | if (likely(disabled == 1)) | |
6fb44b71 | 779 | trace_function(tr, data, ip, parent_ip, flags); |
2e0f5761 IM |
780 | |
781 | atomic_dec(&data->disabled); | |
782 | local_irq_restore(flags); | |
783 | } | |
784 | ||
785 | static struct ftrace_ops trace_ops __read_mostly = | |
786 | { | |
787 | .func = function_trace_call, | |
788 | }; | |
789 | ||
e309b41d | 790 | void tracing_start_function_trace(void) |
2e0f5761 IM |
791 | { |
792 | register_ftrace_function(&trace_ops); | |
793 | } | |
794 | ||
e309b41d | 795 | void tracing_stop_function_trace(void) |
2e0f5761 IM |
796 | { |
797 | unregister_ftrace_function(&trace_ops); | |
798 | } | |
799 | #endif | |
800 | ||
bc0c38d1 SR |
801 | enum trace_file_type { |
802 | TRACE_FILE_LAT_FMT = 1, | |
803 | }; | |
804 | ||
805 | static struct trace_entry * | |
4c11d7ae SR |
806 | trace_entry_idx(struct trace_array *tr, struct trace_array_cpu *data, |
807 | struct trace_iterator *iter, int cpu) | |
bc0c38d1 | 808 | { |
4c11d7ae SR |
809 | struct page *page; |
810 | struct trace_entry *array; | |
bc0c38d1 | 811 | |
4c11d7ae | 812 | if (iter->next_idx[cpu] >= tr->entries || |
b3806b43 SR |
813 | iter->next_idx[cpu] >= data->trace_idx || |
814 | (data->trace_head == data->trace_tail && | |
815 | data->trace_head_idx == data->trace_tail_idx)) | |
bc0c38d1 SR |
816 | return NULL; |
817 | ||
4c11d7ae | 818 | if (!iter->next_page[cpu]) { |
93a588f4 SR |
819 | /* Initialize the iterator for this cpu trace buffer */ |
820 | WARN_ON(!data->trace_tail); | |
821 | page = virt_to_page(data->trace_tail); | |
822 | iter->next_page[cpu] = &page->lru; | |
823 | iter->next_page_idx[cpu] = data->trace_tail_idx; | |
4c11d7ae | 824 | } |
bc0c38d1 | 825 | |
4c11d7ae | 826 | page = list_entry(iter->next_page[cpu], struct page, lru); |
c7aafc54 IM |
827 | BUG_ON(&data->trace_pages == &page->lru); |
828 | ||
4c11d7ae SR |
829 | array = page_address(page); |
830 | ||
93a588f4 | 831 | WARN_ON(iter->next_page_idx[cpu] >= ENTRIES_PER_PAGE); |
4c11d7ae | 832 | return &array[iter->next_page_idx[cpu]]; |
bc0c38d1 SR |
833 | } |
834 | ||
e309b41d | 835 | static struct trace_entry * |
bc0c38d1 SR |
836 | find_next_entry(struct trace_iterator *iter, int *ent_cpu) |
837 | { | |
838 | struct trace_array *tr = iter->tr; | |
839 | struct trace_entry *ent, *next = NULL; | |
840 | int next_cpu = -1; | |
841 | int cpu; | |
842 | ||
843 | for_each_possible_cpu(cpu) { | |
c7aafc54 | 844 | if (!head_page(tr->data[cpu])) |
bc0c38d1 | 845 | continue; |
4c11d7ae | 846 | ent = trace_entry_idx(tr, tr->data[cpu], iter, cpu); |
cdd31cd2 IM |
847 | /* |
848 | * Pick the entry with the smallest timestamp: | |
849 | */ | |
850 | if (ent && (!next || ent->t < next->t)) { | |
bc0c38d1 SR |
851 | next = ent; |
852 | next_cpu = cpu; | |
853 | } | |
854 | } | |
855 | ||
856 | if (ent_cpu) | |
857 | *ent_cpu = next_cpu; | |
858 | ||
859 | return next; | |
860 | } | |
861 | ||
e309b41d | 862 | static void trace_iterator_increment(struct trace_iterator *iter) |
bc0c38d1 | 863 | { |
b3806b43 SR |
864 | iter->idx++; |
865 | iter->next_idx[iter->cpu]++; | |
866 | iter->next_page_idx[iter->cpu]++; | |
8c523a9d | 867 | |
b3806b43 SR |
868 | if (iter->next_page_idx[iter->cpu] >= ENTRIES_PER_PAGE) { |
869 | struct trace_array_cpu *data = iter->tr->data[iter->cpu]; | |
bc0c38d1 | 870 | |
b3806b43 SR |
871 | iter->next_page_idx[iter->cpu] = 0; |
872 | iter->next_page[iter->cpu] = | |
873 | trace_next_list(data, iter->next_page[iter->cpu]); | |
874 | } | |
875 | } | |
bc0c38d1 | 876 | |
e309b41d | 877 | static void trace_consume(struct trace_iterator *iter) |
b3806b43 SR |
878 | { |
879 | struct trace_array_cpu *data = iter->tr->data[iter->cpu]; | |
880 | ||
881 | data->trace_tail_idx++; | |
882 | if (data->trace_tail_idx >= ENTRIES_PER_PAGE) { | |
883 | data->trace_tail = trace_next_page(data, data->trace_tail); | |
884 | data->trace_tail_idx = 0; | |
885 | } | |
4e3c3333 | 886 | |
b3806b43 SR |
887 | /* Check if we empty it, then reset the index */ |
888 | if (data->trace_head == data->trace_tail && | |
889 | data->trace_head_idx == data->trace_tail_idx) | |
890 | data->trace_idx = 0; | |
b3806b43 SR |
891 | } |
892 | ||
e309b41d | 893 | static void *find_next_entry_inc(struct trace_iterator *iter) |
b3806b43 SR |
894 | { |
895 | struct trace_entry *next; | |
896 | int next_cpu = -1; | |
897 | ||
898 | next = find_next_entry(iter, &next_cpu); | |
93a588f4 | 899 | |
4e3c3333 IM |
900 | iter->prev_ent = iter->ent; |
901 | iter->prev_cpu = iter->cpu; | |
902 | ||
bc0c38d1 SR |
903 | iter->ent = next; |
904 | iter->cpu = next_cpu; | |
905 | ||
b3806b43 SR |
906 | if (next) |
907 | trace_iterator_increment(iter); | |
908 | ||
bc0c38d1 SR |
909 | return next ? iter : NULL; |
910 | } | |
911 | ||
e309b41d | 912 | static void *s_next(struct seq_file *m, void *v, loff_t *pos) |
bc0c38d1 SR |
913 | { |
914 | struct trace_iterator *iter = m->private; | |
bc0c38d1 SR |
915 | void *last_ent = iter->ent; |
916 | int i = (int)*pos; | |
4e3c3333 | 917 | void *ent; |
bc0c38d1 SR |
918 | |
919 | (*pos)++; | |
920 | ||
921 | /* can't go backwards */ | |
922 | if (iter->idx > i) | |
923 | return NULL; | |
924 | ||
925 | if (iter->idx < 0) | |
926 | ent = find_next_entry_inc(iter); | |
927 | else | |
928 | ent = iter; | |
929 | ||
930 | while (ent && iter->idx < i) | |
931 | ent = find_next_entry_inc(iter); | |
932 | ||
933 | iter->pos = *pos; | |
934 | ||
935 | if (last_ent && !ent) | |
936 | seq_puts(m, "\n\nvim:ft=help\n"); | |
937 | ||
938 | return ent; | |
939 | } | |
940 | ||
941 | static void *s_start(struct seq_file *m, loff_t *pos) | |
942 | { | |
943 | struct trace_iterator *iter = m->private; | |
944 | void *p = NULL; | |
945 | loff_t l = 0; | |
946 | int i; | |
947 | ||
948 | mutex_lock(&trace_types_lock); | |
949 | ||
d15f57f2 SR |
950 | if (!current_trace || current_trace != iter->trace) { |
951 | mutex_unlock(&trace_types_lock); | |
bc0c38d1 | 952 | return NULL; |
d15f57f2 | 953 | } |
bc0c38d1 SR |
954 | |
955 | atomic_inc(&trace_record_cmdline_disabled); | |
956 | ||
957 | /* let the tracer grab locks here if needed */ | |
958 | if (current_trace->start) | |
959 | current_trace->start(iter); | |
960 | ||
961 | if (*pos != iter->pos) { | |
962 | iter->ent = NULL; | |
963 | iter->cpu = 0; | |
964 | iter->idx = -1; | |
4e3c3333 IM |
965 | iter->prev_ent = NULL; |
966 | iter->prev_cpu = -1; | |
bc0c38d1 | 967 | |
4c11d7ae | 968 | for_each_possible_cpu(i) { |
bc0c38d1 | 969 | iter->next_idx[i] = 0; |
4c11d7ae SR |
970 | iter->next_page[i] = NULL; |
971 | } | |
bc0c38d1 SR |
972 | |
973 | for (p = iter; p && l < *pos; p = s_next(m, p, &l)) | |
974 | ; | |
975 | ||
976 | } else { | |
4c11d7ae | 977 | l = *pos - 1; |
bc0c38d1 SR |
978 | p = s_next(m, p, &l); |
979 | } | |
980 | ||
981 | return p; | |
982 | } | |
983 | ||
984 | static void s_stop(struct seq_file *m, void *p) | |
985 | { | |
986 | struct trace_iterator *iter = m->private; | |
987 | ||
988 | atomic_dec(&trace_record_cmdline_disabled); | |
989 | ||
990 | /* let the tracer release locks here if needed */ | |
991 | if (current_trace && current_trace == iter->trace && iter->trace->stop) | |
992 | iter->trace->stop(iter); | |
993 | ||
994 | mutex_unlock(&trace_types_lock); | |
995 | } | |
996 | ||
b3806b43 | 997 | static int |
214023c3 | 998 | seq_print_sym_short(struct trace_seq *s, const char *fmt, unsigned long address) |
bc0c38d1 SR |
999 | { |
1000 | #ifdef CONFIG_KALLSYMS | |
1001 | char str[KSYM_SYMBOL_LEN]; | |
1002 | ||
1003 | kallsyms_lookup(address, NULL, NULL, NULL, str); | |
1004 | ||
b3806b43 | 1005 | return trace_seq_printf(s, fmt, str); |
bc0c38d1 | 1006 | #endif |
b3806b43 | 1007 | return 1; |
bc0c38d1 SR |
1008 | } |
1009 | ||
b3806b43 | 1010 | static int |
214023c3 SR |
1011 | seq_print_sym_offset(struct trace_seq *s, const char *fmt, |
1012 | unsigned long address) | |
bc0c38d1 SR |
1013 | { |
1014 | #ifdef CONFIG_KALLSYMS | |
1015 | char str[KSYM_SYMBOL_LEN]; | |
1016 | ||
1017 | sprint_symbol(str, address); | |
b3806b43 | 1018 | return trace_seq_printf(s, fmt, str); |
bc0c38d1 | 1019 | #endif |
b3806b43 | 1020 | return 1; |
bc0c38d1 SR |
1021 | } |
1022 | ||
1023 | #ifndef CONFIG_64BIT | |
1024 | # define IP_FMT "%08lx" | |
1025 | #else | |
1026 | # define IP_FMT "%016lx" | |
1027 | #endif | |
1028 | ||
e309b41d | 1029 | static int |
214023c3 | 1030 | seq_print_ip_sym(struct trace_seq *s, unsigned long ip, unsigned long sym_flags) |
bc0c38d1 | 1031 | { |
b3806b43 SR |
1032 | int ret; |
1033 | ||
1034 | if (!ip) | |
1035 | return trace_seq_printf(s, "0"); | |
bc0c38d1 SR |
1036 | |
1037 | if (sym_flags & TRACE_ITER_SYM_OFFSET) | |
b3806b43 | 1038 | ret = seq_print_sym_offset(s, "%s", ip); |
bc0c38d1 | 1039 | else |
b3806b43 SR |
1040 | ret = seq_print_sym_short(s, "%s", ip); |
1041 | ||
1042 | if (!ret) | |
1043 | return 0; | |
bc0c38d1 SR |
1044 | |
1045 | if (sym_flags & TRACE_ITER_SYM_ADDR) | |
b3806b43 SR |
1046 | ret = trace_seq_printf(s, " <" IP_FMT ">", ip); |
1047 | return ret; | |
bc0c38d1 SR |
1048 | } |
1049 | ||
e309b41d | 1050 | static void print_lat_help_header(struct seq_file *m) |
bc0c38d1 SR |
1051 | { |
1052 | seq_puts(m, "# _------=> CPU# \n"); | |
1053 | seq_puts(m, "# / _-----=> irqs-off \n"); | |
1054 | seq_puts(m, "# | / _----=> need-resched \n"); | |
1055 | seq_puts(m, "# || / _---=> hardirq/softirq \n"); | |
1056 | seq_puts(m, "# ||| / _--=> preempt-depth \n"); | |
1057 | seq_puts(m, "# |||| / \n"); | |
1058 | seq_puts(m, "# ||||| delay \n"); | |
1059 | seq_puts(m, "# cmd pid ||||| time | caller \n"); | |
1060 | seq_puts(m, "# \\ / ||||| \\ | / \n"); | |
1061 | } | |
1062 | ||
e309b41d | 1063 | static void print_func_help_header(struct seq_file *m) |
bc0c38d1 SR |
1064 | { |
1065 | seq_puts(m, "# TASK-PID CPU# TIMESTAMP FUNCTION\n"); | |
1066 | seq_puts(m, "# | | | | |\n"); | |
1067 | } | |
1068 | ||
1069 | ||
e309b41d | 1070 | static void |
bc0c38d1 SR |
1071 | print_trace_header(struct seq_file *m, struct trace_iterator *iter) |
1072 | { | |
1073 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); | |
1074 | struct trace_array *tr = iter->tr; | |
1075 | struct trace_array_cpu *data = tr->data[tr->cpu]; | |
1076 | struct tracer *type = current_trace; | |
4c11d7ae SR |
1077 | unsigned long total = 0; |
1078 | unsigned long entries = 0; | |
bc0c38d1 SR |
1079 | int cpu; |
1080 | const char *name = "preemption"; | |
1081 | ||
1082 | if (type) | |
1083 | name = type->name; | |
1084 | ||
1085 | for_each_possible_cpu(cpu) { | |
c7aafc54 | 1086 | if (head_page(tr->data[cpu])) { |
4c11d7ae SR |
1087 | total += tr->data[cpu]->trace_idx; |
1088 | if (tr->data[cpu]->trace_idx > tr->entries) | |
bc0c38d1 | 1089 | entries += tr->entries; |
4c11d7ae | 1090 | else |
bc0c38d1 SR |
1091 | entries += tr->data[cpu]->trace_idx; |
1092 | } | |
1093 | } | |
1094 | ||
1095 | seq_printf(m, "%s latency trace v1.1.5 on %s\n", | |
1096 | name, UTS_RELEASE); | |
1097 | seq_puts(m, "-----------------------------------" | |
1098 | "---------------------------------\n"); | |
1099 | seq_printf(m, " latency: %lu us, #%lu/%lu, CPU#%d |" | |
1100 | " (M:%s VP:%d, KP:%d, SP:%d HP:%d", | |
57f50be1 | 1101 | nsecs_to_usecs(data->saved_latency), |
bc0c38d1 | 1102 | entries, |
4c11d7ae | 1103 | total, |
bc0c38d1 SR |
1104 | tr->cpu, |
1105 | #if defined(CONFIG_PREEMPT_NONE) | |
1106 | "server", | |
1107 | #elif defined(CONFIG_PREEMPT_VOLUNTARY) | |
1108 | "desktop", | |
1109 | #elif defined(CONFIG_PREEMPT_DESKTOP) | |
1110 | "preempt", | |
1111 | #else | |
1112 | "unknown", | |
1113 | #endif | |
1114 | /* These are reserved for later use */ | |
1115 | 0, 0, 0, 0); | |
1116 | #ifdef CONFIG_SMP | |
1117 | seq_printf(m, " #P:%d)\n", num_online_cpus()); | |
1118 | #else | |
1119 | seq_puts(m, ")\n"); | |
1120 | #endif | |
1121 | seq_puts(m, " -----------------\n"); | |
1122 | seq_printf(m, " | task: %.16s-%d " | |
1123 | "(uid:%d nice:%ld policy:%ld rt_prio:%ld)\n", | |
1124 | data->comm, data->pid, data->uid, data->nice, | |
1125 | data->policy, data->rt_priority); | |
1126 | seq_puts(m, " -----------------\n"); | |
1127 | ||
1128 | if (data->critical_start) { | |
1129 | seq_puts(m, " => started at: "); | |
214023c3 SR |
1130 | seq_print_ip_sym(&iter->seq, data->critical_start, sym_flags); |
1131 | trace_print_seq(m, &iter->seq); | |
bc0c38d1 | 1132 | seq_puts(m, "\n => ended at: "); |
214023c3 SR |
1133 | seq_print_ip_sym(&iter->seq, data->critical_end, sym_flags); |
1134 | trace_print_seq(m, &iter->seq); | |
bc0c38d1 SR |
1135 | seq_puts(m, "\n"); |
1136 | } | |
1137 | ||
1138 | seq_puts(m, "\n"); | |
1139 | } | |
1140 | ||
e309b41d | 1141 | static void |
214023c3 | 1142 | lat_print_generic(struct trace_seq *s, struct trace_entry *entry, int cpu) |
bc0c38d1 SR |
1143 | { |
1144 | int hardirq, softirq; | |
1145 | char *comm; | |
1146 | ||
1147 | comm = trace_find_cmdline(entry->pid); | |
1148 | ||
214023c3 SR |
1149 | trace_seq_printf(s, "%8.8s-%-5d ", comm, entry->pid); |
1150 | trace_seq_printf(s, "%d", cpu); | |
1151 | trace_seq_printf(s, "%c%c", | |
1152 | (entry->flags & TRACE_FLAG_IRQS_OFF) ? 'd' : '.', | |
1153 | ((entry->flags & TRACE_FLAG_NEED_RESCHED) ? 'N' : '.')); | |
bc0c38d1 SR |
1154 | |
1155 | hardirq = entry->flags & TRACE_FLAG_HARDIRQ; | |
1156 | softirq = entry->flags & TRACE_FLAG_SOFTIRQ; | |
afc2abc0 | 1157 | if (hardirq && softirq) { |
214023c3 | 1158 | trace_seq_putc(s, 'H'); |
afc2abc0 IM |
1159 | } else { |
1160 | if (hardirq) { | |
214023c3 | 1161 | trace_seq_putc(s, 'h'); |
afc2abc0 | 1162 | } else { |
bc0c38d1 | 1163 | if (softirq) |
214023c3 | 1164 | trace_seq_putc(s, 's'); |
bc0c38d1 | 1165 | else |
214023c3 | 1166 | trace_seq_putc(s, '.'); |
bc0c38d1 SR |
1167 | } |
1168 | } | |
1169 | ||
1170 | if (entry->preempt_count) | |
214023c3 | 1171 | trace_seq_printf(s, "%x", entry->preempt_count); |
bc0c38d1 | 1172 | else |
214023c3 | 1173 | trace_seq_puts(s, "."); |
bc0c38d1 SR |
1174 | } |
1175 | ||
1176 | unsigned long preempt_mark_thresh = 100; | |
1177 | ||
e309b41d | 1178 | static void |
214023c3 | 1179 | lat_print_timestamp(struct trace_seq *s, unsigned long long abs_usecs, |
bc0c38d1 SR |
1180 | unsigned long rel_usecs) |
1181 | { | |
214023c3 | 1182 | trace_seq_printf(s, " %4lldus", abs_usecs); |
bc0c38d1 | 1183 | if (rel_usecs > preempt_mark_thresh) |
214023c3 | 1184 | trace_seq_puts(s, "!: "); |
bc0c38d1 | 1185 | else if (rel_usecs > 1) |
214023c3 | 1186 | trace_seq_puts(s, "+: "); |
bc0c38d1 | 1187 | else |
214023c3 | 1188 | trace_seq_puts(s, " : "); |
bc0c38d1 SR |
1189 | } |
1190 | ||
1191 | static const char state_to_char[] = TASK_STATE_TO_CHAR_STR; | |
1192 | ||
e309b41d | 1193 | static int |
214023c3 | 1194 | print_lat_fmt(struct trace_iterator *iter, unsigned int trace_idx, int cpu) |
bc0c38d1 | 1195 | { |
214023c3 | 1196 | struct trace_seq *s = &iter->seq; |
bc0c38d1 SR |
1197 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); |
1198 | struct trace_entry *next_entry = find_next_entry(iter, NULL); | |
1199 | unsigned long verbose = (trace_flags & TRACE_ITER_VERBOSE); | |
1200 | struct trace_entry *entry = iter->ent; | |
1201 | unsigned long abs_usecs; | |
1202 | unsigned long rel_usecs; | |
1203 | char *comm; | |
bac524d3 | 1204 | int S, T; |
86387f7e | 1205 | int i; |
d17d9691 | 1206 | unsigned state; |
bc0c38d1 SR |
1207 | |
1208 | if (!next_entry) | |
1209 | next_entry = entry; | |
1210 | rel_usecs = ns2usecs(next_entry->t - entry->t); | |
1211 | abs_usecs = ns2usecs(entry->t - iter->tr->time_start); | |
1212 | ||
1213 | if (verbose) { | |
1214 | comm = trace_find_cmdline(entry->pid); | |
214023c3 SR |
1215 | trace_seq_printf(s, "%16s %5d %d %d %08x %08x [%08lx]" |
1216 | " %ld.%03ldms (+%ld.%03ldms): ", | |
1217 | comm, | |
1218 | entry->pid, cpu, entry->flags, | |
1219 | entry->preempt_count, trace_idx, | |
1220 | ns2usecs(entry->t), | |
1221 | abs_usecs/1000, | |
1222 | abs_usecs % 1000, rel_usecs/1000, | |
1223 | rel_usecs % 1000); | |
bc0c38d1 | 1224 | } else { |
f29c73fe IM |
1225 | lat_print_generic(s, entry, cpu); |
1226 | lat_print_timestamp(s, abs_usecs, rel_usecs); | |
bc0c38d1 SR |
1227 | } |
1228 | switch (entry->type) { | |
1229 | case TRACE_FN: | |
214023c3 SR |
1230 | seq_print_ip_sym(s, entry->fn.ip, sym_flags); |
1231 | trace_seq_puts(s, " ("); | |
1232 | seq_print_ip_sym(s, entry->fn.parent_ip, sym_flags); | |
1233 | trace_seq_puts(s, ")\n"); | |
bc0c38d1 SR |
1234 | break; |
1235 | case TRACE_CTX: | |
57422797 | 1236 | case TRACE_WAKE: |
bac524d3 PZ |
1237 | T = entry->ctx.next_state < sizeof(state_to_char) ? |
1238 | state_to_char[entry->ctx.next_state] : 'X'; | |
1239 | ||
d17d9691 AG |
1240 | state = entry->ctx.prev_state ? __ffs(entry->ctx.prev_state) + 1 : 0; |
1241 | S = state < sizeof(state_to_char) - 1 ? state_to_char[state] : 'X'; | |
bc0c38d1 | 1242 | comm = trace_find_cmdline(entry->ctx.next_pid); |
bac524d3 | 1243 | trace_seq_printf(s, " %5d:%3d:%c %s %5d:%3d:%c %s\n", |
214023c3 SR |
1244 | entry->ctx.prev_pid, |
1245 | entry->ctx.prev_prio, | |
57422797 | 1246 | S, entry->type == TRACE_CTX ? "==>" : " +", |
214023c3 SR |
1247 | entry->ctx.next_pid, |
1248 | entry->ctx.next_prio, | |
bac524d3 | 1249 | T, comm); |
bc0c38d1 | 1250 | break; |
f0a920d5 | 1251 | case TRACE_SPECIAL: |
88a4216c | 1252 | trace_seq_printf(s, "# %ld %ld %ld\n", |
f0a920d5 IM |
1253 | entry->special.arg1, |
1254 | entry->special.arg2, | |
1255 | entry->special.arg3); | |
1256 | break; | |
86387f7e IM |
1257 | case TRACE_STACK: |
1258 | for (i = 0; i < FTRACE_STACK_ENTRIES; i++) { | |
1259 | if (i) | |
1260 | trace_seq_puts(s, " <= "); | |
1261 | seq_print_ip_sym(s, entry->stack.caller[i], sym_flags); | |
1262 | } | |
1263 | trace_seq_puts(s, "\n"); | |
1264 | break; | |
89b2f978 | 1265 | default: |
214023c3 | 1266 | trace_seq_printf(s, "Unknown type %d\n", entry->type); |
bc0c38d1 | 1267 | } |
f9896bf3 | 1268 | return 1; |
bc0c38d1 SR |
1269 | } |
1270 | ||
e309b41d | 1271 | static int print_trace_fmt(struct trace_iterator *iter) |
bc0c38d1 | 1272 | { |
214023c3 | 1273 | struct trace_seq *s = &iter->seq; |
bc0c38d1 | 1274 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); |
4e3c3333 | 1275 | struct trace_entry *entry; |
bc0c38d1 SR |
1276 | unsigned long usec_rem; |
1277 | unsigned long long t; | |
1278 | unsigned long secs; | |
1279 | char *comm; | |
b3806b43 | 1280 | int ret; |
bac524d3 | 1281 | int S, T; |
86387f7e | 1282 | int i; |
bc0c38d1 | 1283 | |
4e3c3333 IM |
1284 | entry = iter->ent; |
1285 | ||
bc0c38d1 SR |
1286 | comm = trace_find_cmdline(iter->ent->pid); |
1287 | ||
cdd31cd2 | 1288 | t = ns2usecs(entry->t); |
bc0c38d1 SR |
1289 | usec_rem = do_div(t, 1000000ULL); |
1290 | secs = (unsigned long)t; | |
1291 | ||
f29c73fe IM |
1292 | ret = trace_seq_printf(s, "%16s-%-5d ", comm, entry->pid); |
1293 | if (!ret) | |
1294 | return 0; | |
1295 | ret = trace_seq_printf(s, "[%02d] ", iter->cpu); | |
1296 | if (!ret) | |
1297 | return 0; | |
1298 | ret = trace_seq_printf(s, "%5lu.%06lu: ", secs, usec_rem); | |
1299 | if (!ret) | |
1300 | return 0; | |
bc0c38d1 SR |
1301 | |
1302 | switch (entry->type) { | |
1303 | case TRACE_FN: | |
b3806b43 SR |
1304 | ret = seq_print_ip_sym(s, entry->fn.ip, sym_flags); |
1305 | if (!ret) | |
1306 | return 0; | |
bc0c38d1 SR |
1307 | if ((sym_flags & TRACE_ITER_PRINT_PARENT) && |
1308 | entry->fn.parent_ip) { | |
b3806b43 SR |
1309 | ret = trace_seq_printf(s, " <-"); |
1310 | if (!ret) | |
1311 | return 0; | |
1312 | ret = seq_print_ip_sym(s, entry->fn.parent_ip, | |
1313 | sym_flags); | |
1314 | if (!ret) | |
1315 | return 0; | |
bc0c38d1 | 1316 | } |
b3806b43 SR |
1317 | ret = trace_seq_printf(s, "\n"); |
1318 | if (!ret) | |
1319 | return 0; | |
bc0c38d1 SR |
1320 | break; |
1321 | case TRACE_CTX: | |
57422797 | 1322 | case TRACE_WAKE: |
bc0c38d1 SR |
1323 | S = entry->ctx.prev_state < sizeof(state_to_char) ? |
1324 | state_to_char[entry->ctx.prev_state] : 'X'; | |
bac524d3 PZ |
1325 | T = entry->ctx.next_state < sizeof(state_to_char) ? |
1326 | state_to_char[entry->ctx.next_state] : 'X'; | |
1327 | ret = trace_seq_printf(s, " %5d:%3d:%c %s %5d:%3d:%c\n", | |
b3806b43 SR |
1328 | entry->ctx.prev_pid, |
1329 | entry->ctx.prev_prio, | |
1330 | S, | |
57422797 | 1331 | entry->type == TRACE_CTX ? "==>" : " +", |
b3806b43 | 1332 | entry->ctx.next_pid, |
bac524d3 PZ |
1333 | entry->ctx.next_prio, |
1334 | T); | |
b3806b43 SR |
1335 | if (!ret) |
1336 | return 0; | |
bc0c38d1 | 1337 | break; |
f0a920d5 | 1338 | case TRACE_SPECIAL: |
88a4216c | 1339 | ret = trace_seq_printf(s, "# %ld %ld %ld\n", |
f0a920d5 IM |
1340 | entry->special.arg1, |
1341 | entry->special.arg2, | |
1342 | entry->special.arg3); | |
1343 | if (!ret) | |
1344 | return 0; | |
1345 | break; | |
86387f7e IM |
1346 | case TRACE_STACK: |
1347 | for (i = 0; i < FTRACE_STACK_ENTRIES; i++) { | |
1348 | if (i) { | |
1349 | ret = trace_seq_puts(s, " <= "); | |
1350 | if (!ret) | |
1351 | return 0; | |
1352 | } | |
1353 | ret = seq_print_ip_sym(s, entry->stack.caller[i], | |
1354 | sym_flags); | |
1355 | if (!ret) | |
1356 | return 0; | |
1357 | } | |
1358 | ret = trace_seq_puts(s, "\n"); | |
1359 | if (!ret) | |
1360 | return 0; | |
1361 | break; | |
bc0c38d1 | 1362 | } |
b3806b43 | 1363 | return 1; |
bc0c38d1 SR |
1364 | } |
1365 | ||
e309b41d | 1366 | static int print_raw_fmt(struct trace_iterator *iter) |
f9896bf3 IM |
1367 | { |
1368 | struct trace_seq *s = &iter->seq; | |
1369 | struct trace_entry *entry; | |
1370 | int ret; | |
bac524d3 | 1371 | int S, T; |
f9896bf3 IM |
1372 | |
1373 | entry = iter->ent; | |
1374 | ||
1375 | ret = trace_seq_printf(s, "%d %d %llu ", | |
1376 | entry->pid, iter->cpu, entry->t); | |
1377 | if (!ret) | |
1378 | return 0; | |
1379 | ||
1380 | switch (entry->type) { | |
1381 | case TRACE_FN: | |
1382 | ret = trace_seq_printf(s, "%x %x\n", | |
1383 | entry->fn.ip, entry->fn.parent_ip); | |
1384 | if (!ret) | |
1385 | return 0; | |
1386 | break; | |
1387 | case TRACE_CTX: | |
57422797 | 1388 | case TRACE_WAKE: |
f9896bf3 IM |
1389 | S = entry->ctx.prev_state < sizeof(state_to_char) ? |
1390 | state_to_char[entry->ctx.prev_state] : 'X'; | |
bac524d3 PZ |
1391 | T = entry->ctx.next_state < sizeof(state_to_char) ? |
1392 | state_to_char[entry->ctx.next_state] : 'X'; | |
57422797 IM |
1393 | if (entry->type == TRACE_WAKE) |
1394 | S = '+'; | |
bac524d3 | 1395 | ret = trace_seq_printf(s, "%d %d %c %d %d %c\n", |
f9896bf3 IM |
1396 | entry->ctx.prev_pid, |
1397 | entry->ctx.prev_prio, | |
1398 | S, | |
1399 | entry->ctx.next_pid, | |
bac524d3 PZ |
1400 | entry->ctx.next_prio, |
1401 | T); | |
f9896bf3 IM |
1402 | if (!ret) |
1403 | return 0; | |
1404 | break; | |
f0a920d5 | 1405 | case TRACE_SPECIAL: |
86387f7e | 1406 | case TRACE_STACK: |
88a4216c | 1407 | ret = trace_seq_printf(s, "# %ld %ld %ld\n", |
f0a920d5 IM |
1408 | entry->special.arg1, |
1409 | entry->special.arg2, | |
1410 | entry->special.arg3); | |
1411 | if (!ret) | |
1412 | return 0; | |
1413 | break; | |
f9896bf3 IM |
1414 | } |
1415 | return 1; | |
1416 | } | |
1417 | ||
cb0f12aa IM |
1418 | #define SEQ_PUT_FIELD_RET(s, x) \ |
1419 | do { \ | |
1420 | if (!trace_seq_putmem(s, &(x), sizeof(x))) \ | |
1421 | return 0; \ | |
1422 | } while (0) | |
1423 | ||
5e3ca0ec IM |
1424 | #define SEQ_PUT_HEX_FIELD_RET(s, x) \ |
1425 | do { \ | |
1426 | if (!trace_seq_putmem_hex(s, &(x), sizeof(x))) \ | |
1427 | return 0; \ | |
1428 | } while (0) | |
1429 | ||
e309b41d | 1430 | static int print_hex_fmt(struct trace_iterator *iter) |
5e3ca0ec IM |
1431 | { |
1432 | struct trace_seq *s = &iter->seq; | |
1433 | unsigned char newline = '\n'; | |
1434 | struct trace_entry *entry; | |
bac524d3 | 1435 | int S, T; |
5e3ca0ec IM |
1436 | |
1437 | entry = iter->ent; | |
1438 | ||
1439 | SEQ_PUT_HEX_FIELD_RET(s, entry->pid); | |
1440 | SEQ_PUT_HEX_FIELD_RET(s, iter->cpu); | |
1441 | SEQ_PUT_HEX_FIELD_RET(s, entry->t); | |
1442 | ||
1443 | switch (entry->type) { | |
1444 | case TRACE_FN: | |
1445 | SEQ_PUT_HEX_FIELD_RET(s, entry->fn.ip); | |
1446 | SEQ_PUT_HEX_FIELD_RET(s, entry->fn.parent_ip); | |
1447 | break; | |
1448 | case TRACE_CTX: | |
57422797 | 1449 | case TRACE_WAKE: |
5e3ca0ec IM |
1450 | S = entry->ctx.prev_state < sizeof(state_to_char) ? |
1451 | state_to_char[entry->ctx.prev_state] : 'X'; | |
bac524d3 PZ |
1452 | T = entry->ctx.next_state < sizeof(state_to_char) ? |
1453 | state_to_char[entry->ctx.next_state] : 'X'; | |
57422797 IM |
1454 | if (entry->type == TRACE_WAKE) |
1455 | S = '+'; | |
5e3ca0ec IM |
1456 | SEQ_PUT_HEX_FIELD_RET(s, entry->ctx.prev_pid); |
1457 | SEQ_PUT_HEX_FIELD_RET(s, entry->ctx.prev_prio); | |
1458 | SEQ_PUT_HEX_FIELD_RET(s, S); | |
1459 | SEQ_PUT_HEX_FIELD_RET(s, entry->ctx.next_pid); | |
1460 | SEQ_PUT_HEX_FIELD_RET(s, entry->ctx.next_prio); | |
1461 | SEQ_PUT_HEX_FIELD_RET(s, entry->fn.parent_ip); | |
bac524d3 | 1462 | SEQ_PUT_HEX_FIELD_RET(s, T); |
5e3ca0ec IM |
1463 | break; |
1464 | case TRACE_SPECIAL: | |
86387f7e | 1465 | case TRACE_STACK: |
5e3ca0ec IM |
1466 | SEQ_PUT_HEX_FIELD_RET(s, entry->special.arg1); |
1467 | SEQ_PUT_HEX_FIELD_RET(s, entry->special.arg2); | |
1468 | SEQ_PUT_HEX_FIELD_RET(s, entry->special.arg3); | |
1469 | break; | |
1470 | } | |
1471 | SEQ_PUT_FIELD_RET(s, newline); | |
1472 | ||
1473 | return 1; | |
1474 | } | |
1475 | ||
e309b41d | 1476 | static int print_bin_fmt(struct trace_iterator *iter) |
cb0f12aa IM |
1477 | { |
1478 | struct trace_seq *s = &iter->seq; | |
1479 | struct trace_entry *entry; | |
1480 | ||
1481 | entry = iter->ent; | |
1482 | ||
1483 | SEQ_PUT_FIELD_RET(s, entry->pid); | |
1484 | SEQ_PUT_FIELD_RET(s, entry->cpu); | |
1485 | SEQ_PUT_FIELD_RET(s, entry->t); | |
1486 | ||
1487 | switch (entry->type) { | |
1488 | case TRACE_FN: | |
1489 | SEQ_PUT_FIELD_RET(s, entry->fn.ip); | |
1490 | SEQ_PUT_FIELD_RET(s, entry->fn.parent_ip); | |
1491 | break; | |
1492 | case TRACE_CTX: | |
1493 | SEQ_PUT_FIELD_RET(s, entry->ctx.prev_pid); | |
1494 | SEQ_PUT_FIELD_RET(s, entry->ctx.prev_prio); | |
1495 | SEQ_PUT_FIELD_RET(s, entry->ctx.prev_state); | |
1496 | SEQ_PUT_FIELD_RET(s, entry->ctx.next_pid); | |
1497 | SEQ_PUT_FIELD_RET(s, entry->ctx.next_prio); | |
bac524d3 | 1498 | SEQ_PUT_FIELD_RET(s, entry->ctx.next_state); |
cb0f12aa | 1499 | break; |
f0a920d5 | 1500 | case TRACE_SPECIAL: |
86387f7e | 1501 | case TRACE_STACK: |
f0a920d5 IM |
1502 | SEQ_PUT_FIELD_RET(s, entry->special.arg1); |
1503 | SEQ_PUT_FIELD_RET(s, entry->special.arg2); | |
1504 | SEQ_PUT_FIELD_RET(s, entry->special.arg3); | |
1505 | break; | |
cb0f12aa IM |
1506 | } |
1507 | return 1; | |
1508 | } | |
1509 | ||
bc0c38d1 SR |
1510 | static int trace_empty(struct trace_iterator *iter) |
1511 | { | |
1512 | struct trace_array_cpu *data; | |
1513 | int cpu; | |
1514 | ||
1515 | for_each_possible_cpu(cpu) { | |
1516 | data = iter->tr->data[cpu]; | |
1517 | ||
b3806b43 SR |
1518 | if (head_page(data) && data->trace_idx && |
1519 | (data->trace_tail != data->trace_head || | |
1520 | data->trace_tail_idx != data->trace_head_idx)) | |
bc0c38d1 SR |
1521 | return 0; |
1522 | } | |
1523 | return 1; | |
1524 | } | |
1525 | ||
f9896bf3 IM |
1526 | static int print_trace_line(struct trace_iterator *iter) |
1527 | { | |
72829bc3 TG |
1528 | if (iter->trace && iter->trace->print_line) |
1529 | return iter->trace->print_line(iter); | |
1530 | ||
cb0f12aa IM |
1531 | if (trace_flags & TRACE_ITER_BIN) |
1532 | return print_bin_fmt(iter); | |
1533 | ||
5e3ca0ec IM |
1534 | if (trace_flags & TRACE_ITER_HEX) |
1535 | return print_hex_fmt(iter); | |
1536 | ||
f9896bf3 IM |
1537 | if (trace_flags & TRACE_ITER_RAW) |
1538 | return print_raw_fmt(iter); | |
1539 | ||
1540 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) | |
1541 | return print_lat_fmt(iter, iter->idx, iter->cpu); | |
1542 | ||
1543 | return print_trace_fmt(iter); | |
1544 | } | |
1545 | ||
bc0c38d1 SR |
1546 | static int s_show(struct seq_file *m, void *v) |
1547 | { | |
1548 | struct trace_iterator *iter = v; | |
1549 | ||
1550 | if (iter->ent == NULL) { | |
1551 | if (iter->tr) { | |
1552 | seq_printf(m, "# tracer: %s\n", iter->trace->name); | |
1553 | seq_puts(m, "#\n"); | |
1554 | } | |
1555 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) { | |
1556 | /* print nothing if the buffers are empty */ | |
1557 | if (trace_empty(iter)) | |
1558 | return 0; | |
1559 | print_trace_header(m, iter); | |
1560 | if (!(trace_flags & TRACE_ITER_VERBOSE)) | |
1561 | print_lat_help_header(m); | |
1562 | } else { | |
1563 | if (!(trace_flags & TRACE_ITER_VERBOSE)) | |
1564 | print_func_help_header(m); | |
1565 | } | |
1566 | } else { | |
f9896bf3 | 1567 | print_trace_line(iter); |
214023c3 | 1568 | trace_print_seq(m, &iter->seq); |
bc0c38d1 SR |
1569 | } |
1570 | ||
1571 | return 0; | |
1572 | } | |
1573 | ||
1574 | static struct seq_operations tracer_seq_ops = { | |
4bf39a94 IM |
1575 | .start = s_start, |
1576 | .next = s_next, | |
1577 | .stop = s_stop, | |
1578 | .show = s_show, | |
bc0c38d1 SR |
1579 | }; |
1580 | ||
e309b41d | 1581 | static struct trace_iterator * |
bc0c38d1 SR |
1582 | __tracing_open(struct inode *inode, struct file *file, int *ret) |
1583 | { | |
1584 | struct trace_iterator *iter; | |
1585 | ||
60a11774 SR |
1586 | if (tracing_disabled) { |
1587 | *ret = -ENODEV; | |
1588 | return NULL; | |
1589 | } | |
1590 | ||
bc0c38d1 SR |
1591 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); |
1592 | if (!iter) { | |
1593 | *ret = -ENOMEM; | |
1594 | goto out; | |
1595 | } | |
1596 | ||
1597 | mutex_lock(&trace_types_lock); | |
1598 | if (current_trace && current_trace->print_max) | |
1599 | iter->tr = &max_tr; | |
1600 | else | |
1601 | iter->tr = inode->i_private; | |
1602 | iter->trace = current_trace; | |
1603 | iter->pos = -1; | |
1604 | ||
1605 | /* TODO stop tracer */ | |
1606 | *ret = seq_open(file, &tracer_seq_ops); | |
1607 | if (!*ret) { | |
1608 | struct seq_file *m = file->private_data; | |
1609 | m->private = iter; | |
1610 | ||
1611 | /* stop the trace while dumping */ | |
1612 | if (iter->tr->ctrl) | |
1613 | tracer_enabled = 0; | |
1614 | ||
1615 | if (iter->trace && iter->trace->open) | |
1616 | iter->trace->open(iter); | |
1617 | } else { | |
1618 | kfree(iter); | |
1619 | iter = NULL; | |
1620 | } | |
1621 | mutex_unlock(&trace_types_lock); | |
1622 | ||
1623 | out: | |
1624 | return iter; | |
1625 | } | |
1626 | ||
1627 | int tracing_open_generic(struct inode *inode, struct file *filp) | |
1628 | { | |
60a11774 SR |
1629 | if (tracing_disabled) |
1630 | return -ENODEV; | |
1631 | ||
bc0c38d1 SR |
1632 | filp->private_data = inode->i_private; |
1633 | return 0; | |
1634 | } | |
1635 | ||
1636 | int tracing_release(struct inode *inode, struct file *file) | |
1637 | { | |
1638 | struct seq_file *m = (struct seq_file *)file->private_data; | |
1639 | struct trace_iterator *iter = m->private; | |
1640 | ||
1641 | mutex_lock(&trace_types_lock); | |
1642 | if (iter->trace && iter->trace->close) | |
1643 | iter->trace->close(iter); | |
1644 | ||
1645 | /* reenable tracing if it was previously enabled */ | |
1646 | if (iter->tr->ctrl) | |
1647 | tracer_enabled = 1; | |
1648 | mutex_unlock(&trace_types_lock); | |
1649 | ||
1650 | seq_release(inode, file); | |
1651 | kfree(iter); | |
1652 | return 0; | |
1653 | } | |
1654 | ||
1655 | static int tracing_open(struct inode *inode, struct file *file) | |
1656 | { | |
1657 | int ret; | |
1658 | ||
1659 | __tracing_open(inode, file, &ret); | |
1660 | ||
1661 | return ret; | |
1662 | } | |
1663 | ||
1664 | static int tracing_lt_open(struct inode *inode, struct file *file) | |
1665 | { | |
1666 | struct trace_iterator *iter; | |
1667 | int ret; | |
1668 | ||
1669 | iter = __tracing_open(inode, file, &ret); | |
1670 | ||
1671 | if (!ret) | |
1672 | iter->iter_flags |= TRACE_FILE_LAT_FMT; | |
1673 | ||
1674 | return ret; | |
1675 | } | |
1676 | ||
1677 | ||
e309b41d | 1678 | static void * |
bc0c38d1 SR |
1679 | t_next(struct seq_file *m, void *v, loff_t *pos) |
1680 | { | |
1681 | struct tracer *t = m->private; | |
1682 | ||
1683 | (*pos)++; | |
1684 | ||
1685 | if (t) | |
1686 | t = t->next; | |
1687 | ||
1688 | m->private = t; | |
1689 | ||
1690 | return t; | |
1691 | } | |
1692 | ||
1693 | static void *t_start(struct seq_file *m, loff_t *pos) | |
1694 | { | |
1695 | struct tracer *t = m->private; | |
1696 | loff_t l = 0; | |
1697 | ||
1698 | mutex_lock(&trace_types_lock); | |
1699 | for (; t && l < *pos; t = t_next(m, t, &l)) | |
1700 | ; | |
1701 | ||
1702 | return t; | |
1703 | } | |
1704 | ||
1705 | static void t_stop(struct seq_file *m, void *p) | |
1706 | { | |
1707 | mutex_unlock(&trace_types_lock); | |
1708 | } | |
1709 | ||
1710 | static int t_show(struct seq_file *m, void *v) | |
1711 | { | |
1712 | struct tracer *t = v; | |
1713 | ||
1714 | if (!t) | |
1715 | return 0; | |
1716 | ||
1717 | seq_printf(m, "%s", t->name); | |
1718 | if (t->next) | |
1719 | seq_putc(m, ' '); | |
1720 | else | |
1721 | seq_putc(m, '\n'); | |
1722 | ||
1723 | return 0; | |
1724 | } | |
1725 | ||
1726 | static struct seq_operations show_traces_seq_ops = { | |
4bf39a94 IM |
1727 | .start = t_start, |
1728 | .next = t_next, | |
1729 | .stop = t_stop, | |
1730 | .show = t_show, | |
bc0c38d1 SR |
1731 | }; |
1732 | ||
1733 | static int show_traces_open(struct inode *inode, struct file *file) | |
1734 | { | |
1735 | int ret; | |
1736 | ||
60a11774 SR |
1737 | if (tracing_disabled) |
1738 | return -ENODEV; | |
1739 | ||
bc0c38d1 SR |
1740 | ret = seq_open(file, &show_traces_seq_ops); |
1741 | if (!ret) { | |
1742 | struct seq_file *m = file->private_data; | |
1743 | m->private = trace_types; | |
1744 | } | |
1745 | ||
1746 | return ret; | |
1747 | } | |
1748 | ||
1749 | static struct file_operations tracing_fops = { | |
4bf39a94 IM |
1750 | .open = tracing_open, |
1751 | .read = seq_read, | |
1752 | .llseek = seq_lseek, | |
1753 | .release = tracing_release, | |
bc0c38d1 SR |
1754 | }; |
1755 | ||
1756 | static struct file_operations tracing_lt_fops = { | |
4bf39a94 IM |
1757 | .open = tracing_lt_open, |
1758 | .read = seq_read, | |
1759 | .llseek = seq_lseek, | |
1760 | .release = tracing_release, | |
bc0c38d1 SR |
1761 | }; |
1762 | ||
1763 | static struct file_operations show_traces_fops = { | |
c7078de1 IM |
1764 | .open = show_traces_open, |
1765 | .read = seq_read, | |
1766 | .release = seq_release, | |
1767 | }; | |
1768 | ||
36dfe925 IM |
1769 | /* |
1770 | * Only trace on a CPU if the bitmask is set: | |
1771 | */ | |
1772 | static cpumask_t tracing_cpumask = CPU_MASK_ALL; | |
1773 | ||
1774 | /* | |
1775 | * When tracing/tracing_cpu_mask is modified then this holds | |
1776 | * the new bitmask we are about to install: | |
1777 | */ | |
1778 | static cpumask_t tracing_cpumask_new; | |
1779 | ||
1780 | /* | |
1781 | * The tracer itself will not take this lock, but still we want | |
1782 | * to provide a consistent cpumask to user-space: | |
1783 | */ | |
1784 | static DEFINE_MUTEX(tracing_cpumask_update_lock); | |
1785 | ||
1786 | /* | |
1787 | * Temporary storage for the character representation of the | |
1788 | * CPU bitmask (and one more byte for the newline): | |
1789 | */ | |
1790 | static char mask_str[NR_CPUS + 1]; | |
1791 | ||
c7078de1 IM |
1792 | static ssize_t |
1793 | tracing_cpumask_read(struct file *filp, char __user *ubuf, | |
1794 | size_t count, loff_t *ppos) | |
1795 | { | |
36dfe925 | 1796 | int len; |
c7078de1 IM |
1797 | |
1798 | mutex_lock(&tracing_cpumask_update_lock); | |
36dfe925 IM |
1799 | |
1800 | len = cpumask_scnprintf(mask_str, count, tracing_cpumask); | |
1801 | if (count - len < 2) { | |
1802 | count = -EINVAL; | |
1803 | goto out_err; | |
1804 | } | |
1805 | len += sprintf(mask_str + len, "\n"); | |
1806 | count = simple_read_from_buffer(ubuf, count, ppos, mask_str, NR_CPUS+1); | |
1807 | ||
1808 | out_err: | |
c7078de1 IM |
1809 | mutex_unlock(&tracing_cpumask_update_lock); |
1810 | ||
1811 | return count; | |
1812 | } | |
1813 | ||
1814 | static ssize_t | |
1815 | tracing_cpumask_write(struct file *filp, const char __user *ubuf, | |
1816 | size_t count, loff_t *ppos) | |
1817 | { | |
36dfe925 | 1818 | int err, cpu; |
c7078de1 IM |
1819 | |
1820 | mutex_lock(&tracing_cpumask_update_lock); | |
36dfe925 | 1821 | err = cpumask_parse_user(ubuf, count, tracing_cpumask_new); |
c7078de1 | 1822 | if (err) |
36dfe925 IM |
1823 | goto err_unlock; |
1824 | ||
92205c23 SR |
1825 | raw_local_irq_disable(); |
1826 | __raw_spin_lock(&ftrace_max_lock); | |
36dfe925 IM |
1827 | for_each_possible_cpu(cpu) { |
1828 | /* | |
1829 | * Increase/decrease the disabled counter if we are | |
1830 | * about to flip a bit in the cpumask: | |
1831 | */ | |
1832 | if (cpu_isset(cpu, tracing_cpumask) && | |
1833 | !cpu_isset(cpu, tracing_cpumask_new)) { | |
1834 | atomic_inc(&global_trace.data[cpu]->disabled); | |
1835 | } | |
1836 | if (!cpu_isset(cpu, tracing_cpumask) && | |
1837 | cpu_isset(cpu, tracing_cpumask_new)) { | |
1838 | atomic_dec(&global_trace.data[cpu]->disabled); | |
1839 | } | |
1840 | } | |
92205c23 SR |
1841 | __raw_spin_unlock(&ftrace_max_lock); |
1842 | raw_local_irq_enable(); | |
36dfe925 IM |
1843 | |
1844 | tracing_cpumask = tracing_cpumask_new; | |
1845 | ||
1846 | mutex_unlock(&tracing_cpumask_update_lock); | |
c7078de1 IM |
1847 | |
1848 | return count; | |
36dfe925 IM |
1849 | |
1850 | err_unlock: | |
1851 | mutex_unlock(&tracing_cpumask_update_lock); | |
1852 | ||
1853 | return err; | |
c7078de1 IM |
1854 | } |
1855 | ||
1856 | static struct file_operations tracing_cpumask_fops = { | |
1857 | .open = tracing_open_generic, | |
1858 | .read = tracing_cpumask_read, | |
1859 | .write = tracing_cpumask_write, | |
bc0c38d1 SR |
1860 | }; |
1861 | ||
1862 | static ssize_t | |
1863 | tracing_iter_ctrl_read(struct file *filp, char __user *ubuf, | |
1864 | size_t cnt, loff_t *ppos) | |
1865 | { | |
1866 | char *buf; | |
1867 | int r = 0; | |
1868 | int len = 0; | |
1869 | int i; | |
1870 | ||
1871 | /* calulate max size */ | |
1872 | for (i = 0; trace_options[i]; i++) { | |
1873 | len += strlen(trace_options[i]); | |
1874 | len += 3; /* "no" and space */ | |
1875 | } | |
1876 | ||
1877 | /* +2 for \n and \0 */ | |
1878 | buf = kmalloc(len + 2, GFP_KERNEL); | |
1879 | if (!buf) | |
1880 | return -ENOMEM; | |
1881 | ||
1882 | for (i = 0; trace_options[i]; i++) { | |
1883 | if (trace_flags & (1 << i)) | |
1884 | r += sprintf(buf + r, "%s ", trace_options[i]); | |
1885 | else | |
1886 | r += sprintf(buf + r, "no%s ", trace_options[i]); | |
1887 | } | |
1888 | ||
1889 | r += sprintf(buf + r, "\n"); | |
1890 | WARN_ON(r >= len + 2); | |
1891 | ||
36dfe925 | 1892 | r = simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
1893 | |
1894 | kfree(buf); | |
1895 | ||
1896 | return r; | |
1897 | } | |
1898 | ||
1899 | static ssize_t | |
1900 | tracing_iter_ctrl_write(struct file *filp, const char __user *ubuf, | |
1901 | size_t cnt, loff_t *ppos) | |
1902 | { | |
1903 | char buf[64]; | |
1904 | char *cmp = buf; | |
1905 | int neg = 0; | |
1906 | int i; | |
1907 | ||
cffae437 SR |
1908 | if (cnt >= sizeof(buf)) |
1909 | return -EINVAL; | |
bc0c38d1 SR |
1910 | |
1911 | if (copy_from_user(&buf, ubuf, cnt)) | |
1912 | return -EFAULT; | |
1913 | ||
1914 | buf[cnt] = 0; | |
1915 | ||
1916 | if (strncmp(buf, "no", 2) == 0) { | |
1917 | neg = 1; | |
1918 | cmp += 2; | |
1919 | } | |
1920 | ||
1921 | for (i = 0; trace_options[i]; i++) { | |
1922 | int len = strlen(trace_options[i]); | |
1923 | ||
1924 | if (strncmp(cmp, trace_options[i], len) == 0) { | |
1925 | if (neg) | |
1926 | trace_flags &= ~(1 << i); | |
1927 | else | |
1928 | trace_flags |= (1 << i); | |
1929 | break; | |
1930 | } | |
1931 | } | |
442e544c IM |
1932 | /* |
1933 | * If no option could be set, return an error: | |
1934 | */ | |
1935 | if (!trace_options[i]) | |
1936 | return -EINVAL; | |
bc0c38d1 SR |
1937 | |
1938 | filp->f_pos += cnt; | |
1939 | ||
1940 | return cnt; | |
1941 | } | |
1942 | ||
1943 | static struct file_operations tracing_iter_fops = { | |
c7078de1 IM |
1944 | .open = tracing_open_generic, |
1945 | .read = tracing_iter_ctrl_read, | |
1946 | .write = tracing_iter_ctrl_write, | |
bc0c38d1 SR |
1947 | }; |
1948 | ||
7bd2f24c IM |
1949 | static const char readme_msg[] = |
1950 | "tracing mini-HOWTO:\n\n" | |
1951 | "# mkdir /debug\n" | |
1952 | "# mount -t debugfs nodev /debug\n\n" | |
1953 | "# cat /debug/tracing/available_tracers\n" | |
1954 | "wakeup preemptirqsoff preemptoff irqsoff ftrace sched_switch none\n\n" | |
1955 | "# cat /debug/tracing/current_tracer\n" | |
1956 | "none\n" | |
1957 | "# echo sched_switch > /debug/tracing/current_tracer\n" | |
1958 | "# cat /debug/tracing/current_tracer\n" | |
1959 | "sched_switch\n" | |
1960 | "# cat /debug/tracing/iter_ctrl\n" | |
1961 | "noprint-parent nosym-offset nosym-addr noverbose\n" | |
1962 | "# echo print-parent > /debug/tracing/iter_ctrl\n" | |
1963 | "# echo 1 > /debug/tracing/tracing_enabled\n" | |
1964 | "# cat /debug/tracing/trace > /tmp/trace.txt\n" | |
1965 | "echo 0 > /debug/tracing/tracing_enabled\n" | |
1966 | ; | |
1967 | ||
1968 | static ssize_t | |
1969 | tracing_readme_read(struct file *filp, char __user *ubuf, | |
1970 | size_t cnt, loff_t *ppos) | |
1971 | { | |
1972 | return simple_read_from_buffer(ubuf, cnt, ppos, | |
1973 | readme_msg, strlen(readme_msg)); | |
1974 | } | |
1975 | ||
1976 | static struct file_operations tracing_readme_fops = { | |
c7078de1 IM |
1977 | .open = tracing_open_generic, |
1978 | .read = tracing_readme_read, | |
7bd2f24c IM |
1979 | }; |
1980 | ||
bc0c38d1 SR |
1981 | static ssize_t |
1982 | tracing_ctrl_read(struct file *filp, char __user *ubuf, | |
1983 | size_t cnt, loff_t *ppos) | |
1984 | { | |
1985 | struct trace_array *tr = filp->private_data; | |
1986 | char buf[64]; | |
1987 | int r; | |
1988 | ||
1989 | r = sprintf(buf, "%ld\n", tr->ctrl); | |
4e3c3333 | 1990 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
1991 | } |
1992 | ||
1993 | static ssize_t | |
1994 | tracing_ctrl_write(struct file *filp, const char __user *ubuf, | |
1995 | size_t cnt, loff_t *ppos) | |
1996 | { | |
1997 | struct trace_array *tr = filp->private_data; | |
1998 | long val; | |
1999 | char buf[64]; | |
2000 | ||
cffae437 SR |
2001 | if (cnt >= sizeof(buf)) |
2002 | return -EINVAL; | |
bc0c38d1 SR |
2003 | |
2004 | if (copy_from_user(&buf, ubuf, cnt)) | |
2005 | return -EFAULT; | |
2006 | ||
2007 | buf[cnt] = 0; | |
2008 | ||
2009 | val = simple_strtoul(buf, NULL, 10); | |
2010 | ||
2011 | val = !!val; | |
2012 | ||
2013 | mutex_lock(&trace_types_lock); | |
2014 | if (tr->ctrl ^ val) { | |
2015 | if (val) | |
2016 | tracer_enabled = 1; | |
2017 | else | |
2018 | tracer_enabled = 0; | |
2019 | ||
2020 | tr->ctrl = val; | |
2021 | ||
2022 | if (current_trace && current_trace->ctrl_update) | |
2023 | current_trace->ctrl_update(tr); | |
2024 | } | |
2025 | mutex_unlock(&trace_types_lock); | |
2026 | ||
2027 | filp->f_pos += cnt; | |
2028 | ||
2029 | return cnt; | |
2030 | } | |
2031 | ||
2032 | static ssize_t | |
2033 | tracing_set_trace_read(struct file *filp, char __user *ubuf, | |
2034 | size_t cnt, loff_t *ppos) | |
2035 | { | |
2036 | char buf[max_tracer_type_len+2]; | |
2037 | int r; | |
2038 | ||
2039 | mutex_lock(&trace_types_lock); | |
2040 | if (current_trace) | |
2041 | r = sprintf(buf, "%s\n", current_trace->name); | |
2042 | else | |
2043 | r = sprintf(buf, "\n"); | |
2044 | mutex_unlock(&trace_types_lock); | |
2045 | ||
4bf39a94 | 2046 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
2047 | } |
2048 | ||
2049 | static ssize_t | |
2050 | tracing_set_trace_write(struct file *filp, const char __user *ubuf, | |
2051 | size_t cnt, loff_t *ppos) | |
2052 | { | |
2053 | struct trace_array *tr = &global_trace; | |
2054 | struct tracer *t; | |
2055 | char buf[max_tracer_type_len+1]; | |
2056 | int i; | |
2057 | ||
2058 | if (cnt > max_tracer_type_len) | |
2059 | cnt = max_tracer_type_len; | |
2060 | ||
2061 | if (copy_from_user(&buf, ubuf, cnt)) | |
2062 | return -EFAULT; | |
2063 | ||
2064 | buf[cnt] = 0; | |
2065 | ||
2066 | /* strip ending whitespace. */ | |
2067 | for (i = cnt - 1; i > 0 && isspace(buf[i]); i--) | |
2068 | buf[i] = 0; | |
2069 | ||
2070 | mutex_lock(&trace_types_lock); | |
2071 | for (t = trace_types; t; t = t->next) { | |
2072 | if (strcmp(t->name, buf) == 0) | |
2073 | break; | |
2074 | } | |
2075 | if (!t || t == current_trace) | |
2076 | goto out; | |
2077 | ||
2078 | if (current_trace && current_trace->reset) | |
2079 | current_trace->reset(tr); | |
2080 | ||
2081 | current_trace = t; | |
2082 | if (t->init) | |
2083 | t->init(tr); | |
2084 | ||
2085 | out: | |
2086 | mutex_unlock(&trace_types_lock); | |
2087 | ||
2088 | filp->f_pos += cnt; | |
2089 | ||
2090 | return cnt; | |
2091 | } | |
2092 | ||
2093 | static ssize_t | |
2094 | tracing_max_lat_read(struct file *filp, char __user *ubuf, | |
2095 | size_t cnt, loff_t *ppos) | |
2096 | { | |
2097 | unsigned long *ptr = filp->private_data; | |
2098 | char buf[64]; | |
2099 | int r; | |
2100 | ||
cffae437 | 2101 | r = snprintf(buf, sizeof(buf), "%ld\n", |
bc0c38d1 | 2102 | *ptr == (unsigned long)-1 ? -1 : nsecs_to_usecs(*ptr)); |
cffae437 SR |
2103 | if (r > sizeof(buf)) |
2104 | r = sizeof(buf); | |
4bf39a94 | 2105 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
2106 | } |
2107 | ||
2108 | static ssize_t | |
2109 | tracing_max_lat_write(struct file *filp, const char __user *ubuf, | |
2110 | size_t cnt, loff_t *ppos) | |
2111 | { | |
2112 | long *ptr = filp->private_data; | |
2113 | long val; | |
2114 | char buf[64]; | |
2115 | ||
cffae437 SR |
2116 | if (cnt >= sizeof(buf)) |
2117 | return -EINVAL; | |
bc0c38d1 SR |
2118 | |
2119 | if (copy_from_user(&buf, ubuf, cnt)) | |
2120 | return -EFAULT; | |
2121 | ||
2122 | buf[cnt] = 0; | |
2123 | ||
2124 | val = simple_strtoul(buf, NULL, 10); | |
2125 | ||
2126 | *ptr = val * 1000; | |
2127 | ||
2128 | return cnt; | |
2129 | } | |
2130 | ||
b3806b43 SR |
2131 | static atomic_t tracing_reader; |
2132 | ||
2133 | static int tracing_open_pipe(struct inode *inode, struct file *filp) | |
2134 | { | |
2135 | struct trace_iterator *iter; | |
2136 | ||
2137 | if (tracing_disabled) | |
2138 | return -ENODEV; | |
2139 | ||
2140 | /* We only allow for reader of the pipe */ | |
2141 | if (atomic_inc_return(&tracing_reader) != 1) { | |
2142 | atomic_dec(&tracing_reader); | |
2143 | return -EBUSY; | |
2144 | } | |
2145 | ||
2146 | /* create a buffer to store the information to pass to userspace */ | |
2147 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); | |
2148 | if (!iter) | |
2149 | return -ENOMEM; | |
2150 | ||
2151 | iter->tr = &global_trace; | |
72829bc3 | 2152 | iter->trace = current_trace; |
b3806b43 SR |
2153 | |
2154 | filp->private_data = iter; | |
2155 | ||
2156 | return 0; | |
2157 | } | |
2158 | ||
2159 | static int tracing_release_pipe(struct inode *inode, struct file *file) | |
2160 | { | |
2161 | struct trace_iterator *iter = file->private_data; | |
2162 | ||
2163 | kfree(iter); | |
2164 | atomic_dec(&tracing_reader); | |
2165 | ||
2166 | return 0; | |
2167 | } | |
2168 | ||
2a2cc8f7 SSP |
2169 | static unsigned int |
2170 | tracing_poll_pipe(struct file *filp, poll_table *poll_table) | |
2171 | { | |
2172 | struct trace_iterator *iter = filp->private_data; | |
2173 | ||
2174 | if (trace_flags & TRACE_ITER_BLOCK) { | |
2175 | /* | |
2176 | * Always select as readable when in blocking mode | |
2177 | */ | |
2178 | return POLLIN | POLLRDNORM; | |
afc2abc0 | 2179 | } else { |
2a2cc8f7 SSP |
2180 | if (!trace_empty(iter)) |
2181 | return POLLIN | POLLRDNORM; | |
2182 | poll_wait(filp, &trace_wait, poll_table); | |
2183 | if (!trace_empty(iter)) | |
2184 | return POLLIN | POLLRDNORM; | |
2185 | ||
2186 | return 0; | |
2187 | } | |
2188 | } | |
2189 | ||
b3806b43 SR |
2190 | /* |
2191 | * Consumer reader. | |
2192 | */ | |
2193 | static ssize_t | |
2194 | tracing_read_pipe(struct file *filp, char __user *ubuf, | |
2195 | size_t cnt, loff_t *ppos) | |
2196 | { | |
2197 | struct trace_iterator *iter = filp->private_data; | |
2198 | struct trace_array_cpu *data; | |
b5685aed SR |
2199 | struct trace_array *tr = iter->tr; |
2200 | struct tracer *tracer = iter->trace; | |
b3806b43 | 2201 | static cpumask_t mask; |
b3806b43 SR |
2202 | static int start; |
2203 | unsigned long flags; | |
25770467 | 2204 | #ifdef CONFIG_FTRACE |
2e0f5761 | 2205 | int ftrace_save; |
25770467 | 2206 | #endif |
b3806b43 SR |
2207 | int read = 0; |
2208 | int cpu; | |
2209 | int len; | |
2210 | int ret; | |
2211 | ||
2212 | /* return any leftover data */ | |
2213 | if (iter->seq.len > start) { | |
2214 | len = iter->seq.len - start; | |
2215 | if (cnt > len) | |
2216 | cnt = len; | |
2217 | ret = copy_to_user(ubuf, iter->seq.buffer + start, cnt); | |
2218 | if (ret) | |
2219 | cnt = -EFAULT; | |
2220 | ||
2221 | start += len; | |
2222 | ||
2223 | return cnt; | |
2224 | } | |
2225 | ||
2226 | trace_seq_reset(&iter->seq); | |
2227 | start = 0; | |
2228 | ||
2229 | while (trace_empty(iter)) { | |
2dc8f095 SR |
2230 | |
2231 | if ((filp->f_flags & O_NONBLOCK)) | |
2232 | return -EAGAIN; | |
2233 | ||
b3806b43 SR |
2234 | /* |
2235 | * This is a make-shift waitqueue. The reason we don't use | |
2236 | * an actual wait queue is because: | |
2237 | * 1) we only ever have one waiter | |
2238 | * 2) the tracing, traces all functions, we don't want | |
2239 | * the overhead of calling wake_up and friends | |
2240 | * (and tracing them too) | |
2241 | * Anyway, this is really very primitive wakeup. | |
2242 | */ | |
2243 | set_current_state(TASK_INTERRUPTIBLE); | |
2244 | iter->tr->waiter = current; | |
2245 | ||
2246 | /* sleep for one second, and try again. */ | |
2247 | schedule_timeout(HZ); | |
2248 | ||
2249 | iter->tr->waiter = NULL; | |
2250 | ||
2251 | if (signal_pending(current)) | |
2252 | return -EINTR; | |
2253 | ||
84527997 SR |
2254 | if (iter->trace != current_trace) |
2255 | return 0; | |
2256 | ||
b3806b43 SR |
2257 | /* |
2258 | * We block until we read something and tracing is disabled. | |
2259 | * We still block if tracing is disabled, but we have never | |
2260 | * read anything. This allows a user to cat this file, and | |
2261 | * then enable tracing. But after we have read something, | |
2262 | * we give an EOF when tracing is again disabled. | |
2263 | * | |
2264 | * iter->pos will be 0 if we haven't read anything. | |
2265 | */ | |
2266 | if (!tracer_enabled && iter->pos) | |
2267 | break; | |
2268 | ||
2269 | continue; | |
2270 | } | |
2271 | ||
2272 | /* stop when tracing is finished */ | |
2273 | if (trace_empty(iter)) | |
2274 | return 0; | |
2275 | ||
2276 | if (cnt >= PAGE_SIZE) | |
2277 | cnt = PAGE_SIZE - 1; | |
2278 | ||
2279 | memset(iter, 0, sizeof(*iter)); | |
b5685aed SR |
2280 | iter->tr = tr; |
2281 | iter->trace = tracer; | |
b3806b43 SR |
2282 | iter->pos = -1; |
2283 | ||
2284 | /* | |
2285 | * We need to stop all tracing on all CPUS to read the | |
2286 | * the next buffer. This is a bit expensive, but is | |
2287 | * not done often. We fill all what we can read, | |
2288 | * and then release the locks again. | |
2289 | */ | |
2290 | ||
2291 | cpus_clear(mask); | |
2292 | local_irq_save(flags); | |
25770467 | 2293 | #ifdef CONFIG_FTRACE |
2e0f5761 IM |
2294 | ftrace_save = ftrace_enabled; |
2295 | ftrace_enabled = 0; | |
25770467 | 2296 | #endif |
2e0f5761 | 2297 | smp_wmb(); |
b3806b43 SR |
2298 | for_each_possible_cpu(cpu) { |
2299 | data = iter->tr->data[cpu]; | |
2300 | ||
2301 | if (!head_page(data) || !data->trace_idx) | |
2302 | continue; | |
2303 | ||
2304 | atomic_inc(&data->disabled); | |
b3806b43 SR |
2305 | cpu_set(cpu, mask); |
2306 | } | |
2307 | ||
2e0f5761 IM |
2308 | for_each_cpu_mask(cpu, mask) { |
2309 | data = iter->tr->data[cpu]; | |
92205c23 | 2310 | __raw_spin_lock(&data->lock); |
2e0f5761 IM |
2311 | } |
2312 | ||
088b1e42 SR |
2313 | while (find_next_entry_inc(iter) != NULL) { |
2314 | int len = iter->seq.len; | |
2315 | ||
f9896bf3 | 2316 | ret = print_trace_line(iter); |
088b1e42 SR |
2317 | if (!ret) { |
2318 | /* don't print partial lines */ | |
2319 | iter->seq.len = len; | |
b3806b43 | 2320 | break; |
088b1e42 | 2321 | } |
b3806b43 SR |
2322 | |
2323 | trace_consume(iter); | |
2324 | ||
2325 | if (iter->seq.len >= cnt) | |
2326 | break; | |
b3806b43 SR |
2327 | } |
2328 | ||
d4c5a2f5 | 2329 | for_each_cpu_mask(cpu, mask) { |
b3806b43 | 2330 | data = iter->tr->data[cpu]; |
92205c23 | 2331 | __raw_spin_unlock(&data->lock); |
2e0f5761 IM |
2332 | } |
2333 | ||
2334 | for_each_cpu_mask(cpu, mask) { | |
2335 | data = iter->tr->data[cpu]; | |
b3806b43 SR |
2336 | atomic_dec(&data->disabled); |
2337 | } | |
25770467 | 2338 | #ifdef CONFIG_FTRACE |
2e0f5761 | 2339 | ftrace_enabled = ftrace_save; |
25770467 | 2340 | #endif |
b3806b43 SR |
2341 | local_irq_restore(flags); |
2342 | ||
2343 | /* Now copy what we have to the user */ | |
2344 | read = iter->seq.len; | |
2345 | if (read > cnt) | |
2346 | read = cnt; | |
2347 | ||
2348 | ret = copy_to_user(ubuf, iter->seq.buffer, read); | |
2349 | ||
2350 | if (read < iter->seq.len) | |
2351 | start = read; | |
2352 | else | |
2353 | trace_seq_reset(&iter->seq); | |
2354 | ||
2355 | if (ret) | |
2356 | read = -EFAULT; | |
2357 | ||
2358 | return read; | |
2359 | } | |
2360 | ||
a98a3c3f SR |
2361 | static ssize_t |
2362 | tracing_entries_read(struct file *filp, char __user *ubuf, | |
2363 | size_t cnt, loff_t *ppos) | |
2364 | { | |
2365 | struct trace_array *tr = filp->private_data; | |
2366 | char buf[64]; | |
2367 | int r; | |
2368 | ||
2369 | r = sprintf(buf, "%lu\n", tr->entries); | |
2370 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
2371 | } | |
2372 | ||
2373 | static ssize_t | |
2374 | tracing_entries_write(struct file *filp, const char __user *ubuf, | |
2375 | size_t cnt, loff_t *ppos) | |
2376 | { | |
2377 | unsigned long val; | |
2378 | char buf[64]; | |
2379 | ||
cffae437 SR |
2380 | if (cnt >= sizeof(buf)) |
2381 | return -EINVAL; | |
a98a3c3f SR |
2382 | |
2383 | if (copy_from_user(&buf, ubuf, cnt)) | |
2384 | return -EFAULT; | |
2385 | ||
2386 | buf[cnt] = 0; | |
2387 | ||
2388 | val = simple_strtoul(buf, NULL, 10); | |
2389 | ||
2390 | /* must have at least 1 entry */ | |
2391 | if (!val) | |
2392 | return -EINVAL; | |
2393 | ||
2394 | mutex_lock(&trace_types_lock); | |
2395 | ||
2396 | if (current_trace != &no_tracer) { | |
2397 | cnt = -EBUSY; | |
2398 | pr_info("ftrace: set current_tracer to none" | |
2399 | " before modifying buffer size\n"); | |
2400 | goto out; | |
2401 | } | |
2402 | ||
2403 | if (val > global_trace.entries) { | |
2404 | while (global_trace.entries < val) { | |
2405 | if (trace_alloc_page()) { | |
2406 | cnt = -ENOMEM; | |
2407 | goto out; | |
2408 | } | |
2409 | } | |
2410 | } else { | |
2411 | /* include the number of entries in val (inc of page entries) */ | |
2412 | while (global_trace.entries > val + (ENTRIES_PER_PAGE - 1)) | |
2413 | trace_free_page(); | |
2414 | } | |
2415 | ||
2416 | filp->f_pos += cnt; | |
2417 | ||
2418 | out: | |
2419 | max_tr.entries = global_trace.entries; | |
2420 | mutex_unlock(&trace_types_lock); | |
2421 | ||
2422 | return cnt; | |
2423 | } | |
2424 | ||
bc0c38d1 | 2425 | static struct file_operations tracing_max_lat_fops = { |
4bf39a94 IM |
2426 | .open = tracing_open_generic, |
2427 | .read = tracing_max_lat_read, | |
2428 | .write = tracing_max_lat_write, | |
bc0c38d1 SR |
2429 | }; |
2430 | ||
2431 | static struct file_operations tracing_ctrl_fops = { | |
4bf39a94 IM |
2432 | .open = tracing_open_generic, |
2433 | .read = tracing_ctrl_read, | |
2434 | .write = tracing_ctrl_write, | |
bc0c38d1 SR |
2435 | }; |
2436 | ||
2437 | static struct file_operations set_tracer_fops = { | |
4bf39a94 IM |
2438 | .open = tracing_open_generic, |
2439 | .read = tracing_set_trace_read, | |
2440 | .write = tracing_set_trace_write, | |
bc0c38d1 SR |
2441 | }; |
2442 | ||
b3806b43 | 2443 | static struct file_operations tracing_pipe_fops = { |
4bf39a94 | 2444 | .open = tracing_open_pipe, |
2a2cc8f7 | 2445 | .poll = tracing_poll_pipe, |
4bf39a94 IM |
2446 | .read = tracing_read_pipe, |
2447 | .release = tracing_release_pipe, | |
b3806b43 SR |
2448 | }; |
2449 | ||
a98a3c3f SR |
2450 | static struct file_operations tracing_entries_fops = { |
2451 | .open = tracing_open_generic, | |
2452 | .read = tracing_entries_read, | |
2453 | .write = tracing_entries_write, | |
2454 | }; | |
2455 | ||
bc0c38d1 SR |
2456 | #ifdef CONFIG_DYNAMIC_FTRACE |
2457 | ||
2458 | static ssize_t | |
2459 | tracing_read_long(struct file *filp, char __user *ubuf, | |
2460 | size_t cnt, loff_t *ppos) | |
2461 | { | |
2462 | unsigned long *p = filp->private_data; | |
2463 | char buf[64]; | |
2464 | int r; | |
2465 | ||
2466 | r = sprintf(buf, "%ld\n", *p); | |
4bf39a94 IM |
2467 | |
2468 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
bc0c38d1 SR |
2469 | } |
2470 | ||
2471 | static struct file_operations tracing_read_long_fops = { | |
4bf39a94 IM |
2472 | .open = tracing_open_generic, |
2473 | .read = tracing_read_long, | |
bc0c38d1 SR |
2474 | }; |
2475 | #endif | |
2476 | ||
2477 | static struct dentry *d_tracer; | |
2478 | ||
2479 | struct dentry *tracing_init_dentry(void) | |
2480 | { | |
2481 | static int once; | |
2482 | ||
2483 | if (d_tracer) | |
2484 | return d_tracer; | |
2485 | ||
2486 | d_tracer = debugfs_create_dir("tracing", NULL); | |
2487 | ||
2488 | if (!d_tracer && !once) { | |
2489 | once = 1; | |
2490 | pr_warning("Could not create debugfs directory 'tracing'\n"); | |
2491 | return NULL; | |
2492 | } | |
2493 | ||
2494 | return d_tracer; | |
2495 | } | |
2496 | ||
60a11774 SR |
2497 | #ifdef CONFIG_FTRACE_SELFTEST |
2498 | /* Let selftest have access to static functions in this file */ | |
2499 | #include "trace_selftest.c" | |
2500 | #endif | |
2501 | ||
bc0c38d1 SR |
2502 | static __init void tracer_init_debugfs(void) |
2503 | { | |
2504 | struct dentry *d_tracer; | |
2505 | struct dentry *entry; | |
2506 | ||
2507 | d_tracer = tracing_init_dentry(); | |
2508 | ||
2509 | entry = debugfs_create_file("tracing_enabled", 0644, d_tracer, | |
2510 | &global_trace, &tracing_ctrl_fops); | |
2511 | if (!entry) | |
2512 | pr_warning("Could not create debugfs 'tracing_enabled' entry\n"); | |
2513 | ||
2514 | entry = debugfs_create_file("iter_ctrl", 0644, d_tracer, | |
2515 | NULL, &tracing_iter_fops); | |
2516 | if (!entry) | |
2517 | pr_warning("Could not create debugfs 'iter_ctrl' entry\n"); | |
2518 | ||
c7078de1 IM |
2519 | entry = debugfs_create_file("tracing_cpumask", 0644, d_tracer, |
2520 | NULL, &tracing_cpumask_fops); | |
2521 | if (!entry) | |
2522 | pr_warning("Could not create debugfs 'tracing_cpumask' entry\n"); | |
2523 | ||
bc0c38d1 SR |
2524 | entry = debugfs_create_file("latency_trace", 0444, d_tracer, |
2525 | &global_trace, &tracing_lt_fops); | |
2526 | if (!entry) | |
2527 | pr_warning("Could not create debugfs 'latency_trace' entry\n"); | |
2528 | ||
2529 | entry = debugfs_create_file("trace", 0444, d_tracer, | |
2530 | &global_trace, &tracing_fops); | |
2531 | if (!entry) | |
2532 | pr_warning("Could not create debugfs 'trace' entry\n"); | |
2533 | ||
2534 | entry = debugfs_create_file("available_tracers", 0444, d_tracer, | |
2535 | &global_trace, &show_traces_fops); | |
2536 | if (!entry) | |
2537 | pr_warning("Could not create debugfs 'trace' entry\n"); | |
2538 | ||
2539 | entry = debugfs_create_file("current_tracer", 0444, d_tracer, | |
2540 | &global_trace, &set_tracer_fops); | |
2541 | if (!entry) | |
2542 | pr_warning("Could not create debugfs 'trace' entry\n"); | |
2543 | ||
2544 | entry = debugfs_create_file("tracing_max_latency", 0644, d_tracer, | |
2545 | &tracing_max_latency, | |
2546 | &tracing_max_lat_fops); | |
2547 | if (!entry) | |
2548 | pr_warning("Could not create debugfs " | |
2549 | "'tracing_max_latency' entry\n"); | |
2550 | ||
2551 | entry = debugfs_create_file("tracing_thresh", 0644, d_tracer, | |
2552 | &tracing_thresh, &tracing_max_lat_fops); | |
2553 | if (!entry) | |
2554 | pr_warning("Could not create debugfs " | |
2555 | "'tracing_threash' entry\n"); | |
7bd2f24c IM |
2556 | entry = debugfs_create_file("README", 0644, d_tracer, |
2557 | NULL, &tracing_readme_fops); | |
2558 | if (!entry) | |
2559 | pr_warning("Could not create debugfs 'README' entry\n"); | |
2560 | ||
b3806b43 SR |
2561 | entry = debugfs_create_file("trace_pipe", 0644, d_tracer, |
2562 | NULL, &tracing_pipe_fops); | |
2563 | if (!entry) | |
2564 | pr_warning("Could not create debugfs " | |
2565 | "'tracing_threash' entry\n"); | |
bc0c38d1 | 2566 | |
a98a3c3f SR |
2567 | entry = debugfs_create_file("trace_entries", 0644, d_tracer, |
2568 | &global_trace, &tracing_entries_fops); | |
2569 | if (!entry) | |
2570 | pr_warning("Could not create debugfs " | |
2571 | "'tracing_threash' entry\n"); | |
2572 | ||
bc0c38d1 SR |
2573 | #ifdef CONFIG_DYNAMIC_FTRACE |
2574 | entry = debugfs_create_file("dyn_ftrace_total_info", 0444, d_tracer, | |
2575 | &ftrace_update_tot_cnt, | |
2576 | &tracing_read_long_fops); | |
2577 | if (!entry) | |
2578 | pr_warning("Could not create debugfs " | |
2579 | "'dyn_ftrace_total_info' entry\n"); | |
2580 | #endif | |
2581 | } | |
2582 | ||
4c11d7ae | 2583 | static int trace_alloc_page(void) |
bc0c38d1 | 2584 | { |
4c11d7ae | 2585 | struct trace_array_cpu *data; |
4c11d7ae SR |
2586 | struct page *page, *tmp; |
2587 | LIST_HEAD(pages); | |
c7aafc54 | 2588 | void *array; |
4c11d7ae SR |
2589 | int i; |
2590 | ||
2591 | /* first allocate a page for each CPU */ | |
2592 | for_each_possible_cpu(i) { | |
2593 | array = (void *)__get_free_page(GFP_KERNEL); | |
2594 | if (array == NULL) { | |
2595 | printk(KERN_ERR "tracer: failed to allocate page" | |
2596 | "for trace buffer!\n"); | |
2597 | goto free_pages; | |
2598 | } | |
2599 | ||
2600 | page = virt_to_page(array); | |
2601 | list_add(&page->lru, &pages); | |
2602 | ||
2603 | /* Only allocate if we are actually using the max trace */ | |
2604 | #ifdef CONFIG_TRACER_MAX_TRACE | |
2605 | array = (void *)__get_free_page(GFP_KERNEL); | |
2606 | if (array == NULL) { | |
2607 | printk(KERN_ERR "tracer: failed to allocate page" | |
2608 | "for trace buffer!\n"); | |
2609 | goto free_pages; | |
2610 | } | |
2611 | page = virt_to_page(array); | |
2612 | list_add(&page->lru, &pages); | |
2613 | #endif | |
2614 | } | |
2615 | ||
2616 | /* Now that we successfully allocate a page per CPU, add them */ | |
2617 | for_each_possible_cpu(i) { | |
2618 | data = global_trace.data[i]; | |
2619 | page = list_entry(pages.next, struct page, lru); | |
c7aafc54 | 2620 | list_del_init(&page->lru); |
4c11d7ae SR |
2621 | list_add_tail(&page->lru, &data->trace_pages); |
2622 | ClearPageLRU(page); | |
2623 | ||
2624 | #ifdef CONFIG_TRACER_MAX_TRACE | |
2625 | data = max_tr.data[i]; | |
2626 | page = list_entry(pages.next, struct page, lru); | |
c7aafc54 | 2627 | list_del_init(&page->lru); |
4c11d7ae SR |
2628 | list_add_tail(&page->lru, &data->trace_pages); |
2629 | SetPageLRU(page); | |
2630 | #endif | |
2631 | } | |
2632 | global_trace.entries += ENTRIES_PER_PAGE; | |
2633 | ||
2634 | return 0; | |
2635 | ||
2636 | free_pages: | |
2637 | list_for_each_entry_safe(page, tmp, &pages, lru) { | |
c7aafc54 | 2638 | list_del_init(&page->lru); |
4c11d7ae SR |
2639 | __free_page(page); |
2640 | } | |
2641 | return -ENOMEM; | |
bc0c38d1 SR |
2642 | } |
2643 | ||
a98a3c3f SR |
2644 | static int trace_free_page(void) |
2645 | { | |
2646 | struct trace_array_cpu *data; | |
2647 | struct page *page; | |
2648 | struct list_head *p; | |
2649 | int i; | |
2650 | int ret = 0; | |
2651 | ||
2652 | /* free one page from each buffer */ | |
2653 | for_each_possible_cpu(i) { | |
2654 | data = global_trace.data[i]; | |
2655 | p = data->trace_pages.next; | |
2656 | if (p == &data->trace_pages) { | |
2657 | /* should never happen */ | |
2658 | WARN_ON(1); | |
2659 | tracing_disabled = 1; | |
2660 | ret = -1; | |
2661 | break; | |
2662 | } | |
2663 | page = list_entry(p, struct page, lru); | |
2664 | ClearPageLRU(page); | |
2665 | list_del(&page->lru); | |
2666 | __free_page(page); | |
2667 | ||
2668 | tracing_reset(data); | |
2669 | ||
2670 | #ifdef CONFIG_TRACER_MAX_TRACE | |
2671 | data = max_tr.data[i]; | |
2672 | p = data->trace_pages.next; | |
2673 | if (p == &data->trace_pages) { | |
2674 | /* should never happen */ | |
2675 | WARN_ON(1); | |
2676 | tracing_disabled = 1; | |
2677 | ret = -1; | |
2678 | break; | |
2679 | } | |
2680 | page = list_entry(p, struct page, lru); | |
2681 | ClearPageLRU(page); | |
2682 | list_del(&page->lru); | |
2683 | __free_page(page); | |
2684 | ||
2685 | tracing_reset(data); | |
2686 | #endif | |
2687 | } | |
2688 | global_trace.entries -= ENTRIES_PER_PAGE; | |
2689 | ||
2690 | return ret; | |
2691 | } | |
2692 | ||
bc0c38d1 SR |
2693 | __init static int tracer_alloc_buffers(void) |
2694 | { | |
4c11d7ae SR |
2695 | struct trace_array_cpu *data; |
2696 | void *array; | |
2697 | struct page *page; | |
2698 | int pages = 0; | |
60a11774 | 2699 | int ret = -ENOMEM; |
bc0c38d1 SR |
2700 | int i; |
2701 | ||
26994ead SR |
2702 | global_trace.ctrl = tracer_enabled; |
2703 | ||
4c11d7ae | 2704 | /* Allocate the first page for all buffers */ |
bc0c38d1 | 2705 | for_each_possible_cpu(i) { |
4c11d7ae | 2706 | data = global_trace.data[i] = &per_cpu(global_trace_cpu, i); |
bc0c38d1 SR |
2707 | max_tr.data[i] = &per_cpu(max_data, i); |
2708 | ||
4c11d7ae | 2709 | array = (void *)__get_free_page(GFP_KERNEL); |
bc0c38d1 | 2710 | if (array == NULL) { |
4c11d7ae SR |
2711 | printk(KERN_ERR "tracer: failed to allocate page" |
2712 | "for trace buffer!\n"); | |
bc0c38d1 SR |
2713 | goto free_buffers; |
2714 | } | |
4c11d7ae SR |
2715 | |
2716 | /* set the array to the list */ | |
2717 | INIT_LIST_HEAD(&data->trace_pages); | |
2718 | page = virt_to_page(array); | |
2719 | list_add(&page->lru, &data->trace_pages); | |
2720 | /* use the LRU flag to differentiate the two buffers */ | |
2721 | ClearPageLRU(page); | |
bc0c38d1 | 2722 | |
a98a3c3f SR |
2723 | data->lock = (raw_spinlock_t)__RAW_SPIN_LOCK_UNLOCKED; |
2724 | max_tr.data[i]->lock = (raw_spinlock_t)__RAW_SPIN_LOCK_UNLOCKED; | |
2725 | ||
bc0c38d1 SR |
2726 | /* Only allocate if we are actually using the max trace */ |
2727 | #ifdef CONFIG_TRACER_MAX_TRACE | |
4c11d7ae | 2728 | array = (void *)__get_free_page(GFP_KERNEL); |
bc0c38d1 | 2729 | if (array == NULL) { |
4c11d7ae SR |
2730 | printk(KERN_ERR "tracer: failed to allocate page" |
2731 | "for trace buffer!\n"); | |
bc0c38d1 SR |
2732 | goto free_buffers; |
2733 | } | |
4c11d7ae SR |
2734 | |
2735 | INIT_LIST_HEAD(&max_tr.data[i]->trace_pages); | |
2736 | page = virt_to_page(array); | |
2737 | list_add(&page->lru, &max_tr.data[i]->trace_pages); | |
2738 | SetPageLRU(page); | |
bc0c38d1 SR |
2739 | #endif |
2740 | } | |
2741 | ||
2742 | /* | |
2743 | * Since we allocate by orders of pages, we may be able to | |
2744 | * round up a bit. | |
2745 | */ | |
4c11d7ae | 2746 | global_trace.entries = ENTRIES_PER_PAGE; |
4c11d7ae SR |
2747 | pages++; |
2748 | ||
2749 | while (global_trace.entries < trace_nr_entries) { | |
2750 | if (trace_alloc_page()) | |
2751 | break; | |
2752 | pages++; | |
2753 | } | |
89b2f978 | 2754 | max_tr.entries = global_trace.entries; |
bc0c38d1 | 2755 | |
4c11d7ae SR |
2756 | pr_info("tracer: %d pages allocated for %ld", |
2757 | pages, trace_nr_entries); | |
bc0c38d1 SR |
2758 | pr_info(" entries of %ld bytes\n", (long)TRACE_ENTRY_SIZE); |
2759 | pr_info(" actual entries %ld\n", global_trace.entries); | |
2760 | ||
2761 | tracer_init_debugfs(); | |
2762 | ||
2763 | trace_init_cmdlines(); | |
2764 | ||
2765 | register_tracer(&no_tracer); | |
2766 | current_trace = &no_tracer; | |
2767 | ||
60a11774 SR |
2768 | /* All seems OK, enable tracing */ |
2769 | tracing_disabled = 0; | |
2770 | ||
bc0c38d1 SR |
2771 | return 0; |
2772 | ||
2773 | free_buffers: | |
2774 | for (i-- ; i >= 0; i--) { | |
4c11d7ae | 2775 | struct page *page, *tmp; |
bc0c38d1 SR |
2776 | struct trace_array_cpu *data = global_trace.data[i]; |
2777 | ||
c7aafc54 | 2778 | if (data) { |
4c11d7ae SR |
2779 | list_for_each_entry_safe(page, tmp, |
2780 | &data->trace_pages, lru) { | |
c7aafc54 | 2781 | list_del_init(&page->lru); |
4c11d7ae SR |
2782 | __free_page(page); |
2783 | } | |
bc0c38d1 SR |
2784 | } |
2785 | ||
2786 | #ifdef CONFIG_TRACER_MAX_TRACE | |
2787 | data = max_tr.data[i]; | |
c7aafc54 | 2788 | if (data) { |
4c11d7ae SR |
2789 | list_for_each_entry_safe(page, tmp, |
2790 | &data->trace_pages, lru) { | |
c7aafc54 | 2791 | list_del_init(&page->lru); |
4c11d7ae SR |
2792 | __free_page(page); |
2793 | } | |
bc0c38d1 SR |
2794 | } |
2795 | #endif | |
2796 | } | |
60a11774 | 2797 | return ret; |
bc0c38d1 | 2798 | } |
60a11774 | 2799 | fs_initcall(tracer_alloc_buffers); |