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> | |
76094a2c | 30 | #include <linux/kprobes.h> |
3eefae99 | 31 | #include <linux/writeback.h> |
bc0c38d1 | 32 | |
86387f7e IM |
33 | #include <linux/stacktrace.h> |
34 | ||
bc0c38d1 SR |
35 | #include "trace.h" |
36 | ||
37 | unsigned long __read_mostly tracing_max_latency = (cycle_t)ULONG_MAX; | |
38 | unsigned long __read_mostly tracing_thresh; | |
39 | ||
ab46428c SR |
40 | static unsigned long __read_mostly tracing_nr_buffers; |
41 | static cpumask_t __read_mostly tracing_buffer_mask; | |
42 | ||
43 | #define for_each_tracing_cpu(cpu) \ | |
44 | for_each_cpu_mask(cpu, tracing_buffer_mask) | |
45 | ||
a98a3c3f SR |
46 | static int trace_alloc_page(void); |
47 | static int trace_free_page(void); | |
48 | ||
60a11774 SR |
49 | static int tracing_disabled = 1; |
50 | ||
3eefae99 SR |
51 | static unsigned long tracing_pages_allocated; |
52 | ||
72829bc3 | 53 | long |
bc0c38d1 SR |
54 | ns2usecs(cycle_t nsec) |
55 | { | |
56 | nsec += 500; | |
57 | do_div(nsec, 1000); | |
58 | return nsec; | |
59 | } | |
60 | ||
e309b41d | 61 | cycle_t ftrace_now(int cpu) |
750ed1a4 | 62 | { |
0fd9e0da | 63 | return cpu_clock(cpu); |
750ed1a4 IM |
64 | } |
65 | ||
4fcdae83 SR |
66 | /* |
67 | * The global_trace is the descriptor that holds the tracing | |
68 | * buffers for the live tracing. For each CPU, it contains | |
69 | * a link list of pages that will store trace entries. The | |
70 | * page descriptor of the pages in the memory is used to hold | |
71 | * the link list by linking the lru item in the page descriptor | |
72 | * to each of the pages in the buffer per CPU. | |
73 | * | |
74 | * For each active CPU there is a data field that holds the | |
75 | * pages for the buffer for that CPU. Each CPU has the same number | |
76 | * of pages allocated for its buffer. | |
77 | */ | |
bc0c38d1 SR |
78 | static struct trace_array global_trace; |
79 | ||
80 | static DEFINE_PER_CPU(struct trace_array_cpu, global_trace_cpu); | |
81 | ||
4fcdae83 SR |
82 | /* |
83 | * The max_tr is used to snapshot the global_trace when a maximum | |
84 | * latency is reached. Some tracers will use this to store a maximum | |
85 | * trace while it continues examining live traces. | |
86 | * | |
87 | * The buffers for the max_tr are set up the same as the global_trace. | |
88 | * When a snapshot is taken, the link list of the max_tr is swapped | |
89 | * with the link list of the global_trace and the buffers are reset for | |
90 | * the global_trace so the tracing can continue. | |
91 | */ | |
bc0c38d1 SR |
92 | static struct trace_array max_tr; |
93 | ||
94 | static DEFINE_PER_CPU(struct trace_array_cpu, max_data); | |
95 | ||
4fcdae83 | 96 | /* tracer_enabled is used to toggle activation of a tracer */ |
26994ead | 97 | static int tracer_enabled = 1; |
4fcdae83 | 98 | |
60bc0800 SR |
99 | /* function tracing enabled */ |
100 | int ftrace_function_enabled; | |
101 | ||
4fcdae83 SR |
102 | /* |
103 | * trace_nr_entries is the number of entries that is allocated | |
104 | * for a buffer. Note, the number of entries is always rounded | |
105 | * to ENTRIES_PER_PAGE. | |
106 | */ | |
57422797 | 107 | static unsigned long trace_nr_entries = 65536UL; |
bc0c38d1 | 108 | |
4fcdae83 | 109 | /* trace_types holds a link list of available tracers. */ |
bc0c38d1 | 110 | static struct tracer *trace_types __read_mostly; |
4fcdae83 SR |
111 | |
112 | /* current_trace points to the tracer that is currently active */ | |
bc0c38d1 | 113 | static struct tracer *current_trace __read_mostly; |
4fcdae83 SR |
114 | |
115 | /* | |
116 | * max_tracer_type_len is used to simplify the allocating of | |
117 | * buffers to read userspace tracer names. We keep track of | |
118 | * the longest tracer name registered. | |
119 | */ | |
bc0c38d1 SR |
120 | static int max_tracer_type_len; |
121 | ||
4fcdae83 SR |
122 | /* |
123 | * trace_types_lock is used to protect the trace_types list. | |
124 | * This lock is also used to keep user access serialized. | |
125 | * Accesses from userspace will grab this lock while userspace | |
126 | * activities happen inside the kernel. | |
127 | */ | |
bc0c38d1 | 128 | static DEFINE_MUTEX(trace_types_lock); |
4fcdae83 SR |
129 | |
130 | /* trace_wait is a waitqueue for tasks blocked on trace_poll */ | |
4e655519 IM |
131 | static DECLARE_WAIT_QUEUE_HEAD(trace_wait); |
132 | ||
4fcdae83 | 133 | /* trace_flags holds iter_ctrl options */ |
4e655519 IM |
134 | unsigned long trace_flags = TRACE_ITER_PRINT_PARENT; |
135 | ||
2b1bce17 AG |
136 | static notrace void no_trace_init(struct trace_array *tr) |
137 | { | |
138 | int cpu; | |
139 | ||
60bc0800 | 140 | ftrace_function_enabled = 0; |
2b1bce17 AG |
141 | if(tr->ctrl) |
142 | for_each_online_cpu(cpu) | |
143 | tracing_reset(tr->data[cpu]); | |
144 | tracer_enabled = 0; | |
145 | } | |
146 | ||
147 | /* dummy trace to disable tracing */ | |
148 | static struct tracer no_tracer __read_mostly = { | |
149 | .name = "none", | |
150 | .init = no_trace_init | |
151 | }; | |
152 | ||
153 | ||
4fcdae83 SR |
154 | /** |
155 | * trace_wake_up - wake up tasks waiting for trace input | |
156 | * | |
157 | * Simply wakes up any task that is blocked on the trace_wait | |
158 | * queue. These is used with trace_poll for tasks polling the trace. | |
159 | */ | |
4e655519 IM |
160 | void trace_wake_up(void) |
161 | { | |
017730c1 IM |
162 | /* |
163 | * The runqueue_is_locked() can fail, but this is the best we | |
164 | * have for now: | |
165 | */ | |
166 | if (!(trace_flags & TRACE_ITER_BLOCK) && !runqueue_is_locked()) | |
4e655519 IM |
167 | wake_up(&trace_wait); |
168 | } | |
bc0c38d1 | 169 | |
4c11d7ae SR |
170 | #define ENTRIES_PER_PAGE (PAGE_SIZE / sizeof(struct trace_entry)) |
171 | ||
bc0c38d1 SR |
172 | static int __init set_nr_entries(char *str) |
173 | { | |
c6caeeb1 SR |
174 | unsigned long nr_entries; |
175 | int ret; | |
176 | ||
bc0c38d1 SR |
177 | if (!str) |
178 | return 0; | |
c6caeeb1 SR |
179 | ret = strict_strtoul(str, 0, &nr_entries); |
180 | /* nr_entries can not be zero */ | |
181 | if (ret < 0 || nr_entries == 0) | |
182 | return 0; | |
183 | trace_nr_entries = nr_entries; | |
bc0c38d1 SR |
184 | return 1; |
185 | } | |
186 | __setup("trace_entries=", set_nr_entries); | |
187 | ||
57f50be1 SR |
188 | unsigned long nsecs_to_usecs(unsigned long nsecs) |
189 | { | |
190 | return nsecs / 1000; | |
191 | } | |
192 | ||
4fcdae83 SR |
193 | /* |
194 | * trace_flag_type is an enumeration that holds different | |
195 | * states when a trace occurs. These are: | |
196 | * IRQS_OFF - interrupts were disabled | |
197 | * NEED_RESCED - reschedule is requested | |
198 | * HARDIRQ - inside an interrupt handler | |
199 | * SOFTIRQ - inside a softirq handler | |
200 | */ | |
bc0c38d1 SR |
201 | enum trace_flag_type { |
202 | TRACE_FLAG_IRQS_OFF = 0x01, | |
203 | TRACE_FLAG_NEED_RESCHED = 0x02, | |
204 | TRACE_FLAG_HARDIRQ = 0x04, | |
205 | TRACE_FLAG_SOFTIRQ = 0x08, | |
206 | }; | |
207 | ||
4fcdae83 SR |
208 | /* |
209 | * TRACE_ITER_SYM_MASK masks the options in trace_flags that | |
210 | * control the output of kernel symbols. | |
211 | */ | |
bc0c38d1 SR |
212 | #define TRACE_ITER_SYM_MASK \ |
213 | (TRACE_ITER_PRINT_PARENT|TRACE_ITER_SYM_OFFSET|TRACE_ITER_SYM_ADDR) | |
214 | ||
4fcdae83 | 215 | /* These must match the bit postions in trace_iterator_flags */ |
bc0c38d1 SR |
216 | static const char *trace_options[] = { |
217 | "print-parent", | |
218 | "sym-offset", | |
219 | "sym-addr", | |
220 | "verbose", | |
f9896bf3 | 221 | "raw", |
5e3ca0ec | 222 | "hex", |
cb0f12aa | 223 | "bin", |
2a2cc8f7 | 224 | "block", |
86387f7e | 225 | "stacktrace", |
4ac3ba41 | 226 | "sched-tree", |
bc0c38d1 SR |
227 | NULL |
228 | }; | |
229 | ||
4fcdae83 SR |
230 | /* |
231 | * ftrace_max_lock is used to protect the swapping of buffers | |
232 | * when taking a max snapshot. The buffers themselves are | |
233 | * protected by per_cpu spinlocks. But the action of the swap | |
234 | * needs its own lock. | |
235 | * | |
236 | * This is defined as a raw_spinlock_t in order to help | |
237 | * with performance when lockdep debugging is enabled. | |
238 | */ | |
92205c23 SR |
239 | static raw_spinlock_t ftrace_max_lock = |
240 | (raw_spinlock_t)__RAW_SPIN_LOCK_UNLOCKED; | |
bc0c38d1 SR |
241 | |
242 | /* | |
243 | * Copy the new maximum trace into the separate maximum-trace | |
244 | * structure. (this way the maximum trace is permanently saved, | |
245 | * for later retrieval via /debugfs/tracing/latency_trace) | |
246 | */ | |
e309b41d | 247 | static void |
bc0c38d1 SR |
248 | __update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) |
249 | { | |
250 | struct trace_array_cpu *data = tr->data[cpu]; | |
251 | ||
252 | max_tr.cpu = cpu; | |
253 | max_tr.time_start = data->preempt_timestamp; | |
254 | ||
255 | data = max_tr.data[cpu]; | |
256 | data->saved_latency = tracing_max_latency; | |
257 | ||
258 | memcpy(data->comm, tsk->comm, TASK_COMM_LEN); | |
259 | data->pid = tsk->pid; | |
260 | data->uid = tsk->uid; | |
261 | data->nice = tsk->static_prio - 20 - MAX_RT_PRIO; | |
262 | data->policy = tsk->policy; | |
263 | data->rt_priority = tsk->rt_priority; | |
264 | ||
265 | /* record this tasks comm */ | |
266 | tracing_record_cmdline(current); | |
267 | } | |
268 | ||
19384c03 SR |
269 | #define CHECK_COND(cond) \ |
270 | if (unlikely(cond)) { \ | |
271 | tracing_disabled = 1; \ | |
272 | WARN_ON(1); \ | |
273 | return -1; \ | |
274 | } | |
275 | ||
4fcdae83 SR |
276 | /** |
277 | * check_pages - integrity check of trace buffers | |
278 | * | |
279 | * As a safty measure we check to make sure the data pages have not | |
19384c03 | 280 | * been corrupted. |
4fcdae83 | 281 | */ |
19384c03 | 282 | int check_pages(struct trace_array_cpu *data) |
c7aafc54 IM |
283 | { |
284 | struct page *page, *tmp; | |
285 | ||
19384c03 SR |
286 | CHECK_COND(data->trace_pages.next->prev != &data->trace_pages); |
287 | CHECK_COND(data->trace_pages.prev->next != &data->trace_pages); | |
c7aafc54 IM |
288 | |
289 | list_for_each_entry_safe(page, tmp, &data->trace_pages, lru) { | |
19384c03 SR |
290 | CHECK_COND(page->lru.next->prev != &page->lru); |
291 | CHECK_COND(page->lru.prev->next != &page->lru); | |
c7aafc54 | 292 | } |
19384c03 SR |
293 | |
294 | return 0; | |
c7aafc54 IM |
295 | } |
296 | ||
4fcdae83 SR |
297 | /** |
298 | * head_page - page address of the first page in per_cpu buffer. | |
299 | * | |
300 | * head_page returns the page address of the first page in | |
301 | * a per_cpu buffer. This also preforms various consistency | |
302 | * checks to make sure the buffer has not been corrupted. | |
303 | */ | |
c7aafc54 IM |
304 | void *head_page(struct trace_array_cpu *data) |
305 | { | |
306 | struct page *page; | |
307 | ||
c7aafc54 IM |
308 | if (list_empty(&data->trace_pages)) |
309 | return NULL; | |
310 | ||
311 | page = list_entry(data->trace_pages.next, struct page, lru); | |
312 | BUG_ON(&page->lru == &data->trace_pages); | |
313 | ||
314 | return page_address(page); | |
315 | } | |
316 | ||
4fcdae83 SR |
317 | /** |
318 | * trace_seq_printf - sequence printing of trace information | |
319 | * @s: trace sequence descriptor | |
320 | * @fmt: printf format string | |
321 | * | |
322 | * The tracer may use either sequence operations or its own | |
323 | * copy to user routines. To simplify formating of a trace | |
324 | * trace_seq_printf is used to store strings into a special | |
325 | * buffer (@s). Then the output may be either used by | |
326 | * the sequencer or pulled into another buffer. | |
327 | */ | |
72829bc3 | 328 | int |
214023c3 SR |
329 | trace_seq_printf(struct trace_seq *s, const char *fmt, ...) |
330 | { | |
331 | int len = (PAGE_SIZE - 1) - s->len; | |
332 | va_list ap; | |
b3806b43 | 333 | int ret; |
214023c3 SR |
334 | |
335 | if (!len) | |
336 | return 0; | |
337 | ||
338 | va_start(ap, fmt); | |
b3806b43 | 339 | ret = vsnprintf(s->buffer + s->len, len, fmt, ap); |
214023c3 SR |
340 | va_end(ap); |
341 | ||
b3806b43 | 342 | /* If we can't write it all, don't bother writing anything */ |
72829bc3 | 343 | if (ret >= len) |
b3806b43 SR |
344 | return 0; |
345 | ||
346 | s->len += ret; | |
214023c3 SR |
347 | |
348 | return len; | |
349 | } | |
350 | ||
4fcdae83 SR |
351 | /** |
352 | * trace_seq_puts - trace sequence printing of simple string | |
353 | * @s: trace sequence descriptor | |
354 | * @str: simple string to record | |
355 | * | |
356 | * The tracer may use either the sequence operations or its own | |
357 | * copy to user routines. This function records a simple string | |
358 | * into a special buffer (@s) for later retrieval by a sequencer | |
359 | * or other mechanism. | |
360 | */ | |
e309b41d | 361 | static int |
214023c3 SR |
362 | trace_seq_puts(struct trace_seq *s, const char *str) |
363 | { | |
364 | int len = strlen(str); | |
365 | ||
366 | if (len > ((PAGE_SIZE - 1) - s->len)) | |
b3806b43 | 367 | return 0; |
214023c3 SR |
368 | |
369 | memcpy(s->buffer + s->len, str, len); | |
370 | s->len += len; | |
371 | ||
372 | return len; | |
373 | } | |
374 | ||
e309b41d | 375 | static int |
214023c3 SR |
376 | trace_seq_putc(struct trace_seq *s, unsigned char c) |
377 | { | |
378 | if (s->len >= (PAGE_SIZE - 1)) | |
379 | return 0; | |
380 | ||
381 | s->buffer[s->len++] = c; | |
382 | ||
383 | return 1; | |
384 | } | |
385 | ||
e309b41d | 386 | static int |
cb0f12aa IM |
387 | trace_seq_putmem(struct trace_seq *s, void *mem, size_t len) |
388 | { | |
389 | if (len > ((PAGE_SIZE - 1) - s->len)) | |
390 | return 0; | |
391 | ||
392 | memcpy(s->buffer + s->len, mem, len); | |
393 | s->len += len; | |
394 | ||
395 | return len; | |
396 | } | |
397 | ||
5e3ca0ec | 398 | #define HEX_CHARS 17 |
93dcc6ea | 399 | static const char hex2asc[] = "0123456789abcdef"; |
5e3ca0ec | 400 | |
e309b41d | 401 | static int |
5e3ca0ec IM |
402 | trace_seq_putmem_hex(struct trace_seq *s, void *mem, size_t len) |
403 | { | |
404 | unsigned char hex[HEX_CHARS]; | |
93dcc6ea | 405 | unsigned char *data = mem; |
5e3ca0ec IM |
406 | unsigned char byte; |
407 | int i, j; | |
408 | ||
409 | BUG_ON(len >= HEX_CHARS); | |
410 | ||
5e3ca0ec IM |
411 | #ifdef __BIG_ENDIAN |
412 | for (i = 0, j = 0; i < len; i++) { | |
413 | #else | |
414 | for (i = len-1, j = 0; i >= 0; i--) { | |
415 | #endif | |
416 | byte = data[i]; | |
417 | ||
93dcc6ea TG |
418 | hex[j++] = hex2asc[byte & 0x0f]; |
419 | hex[j++] = hex2asc[byte >> 4]; | |
5e3ca0ec | 420 | } |
93dcc6ea | 421 | hex[j++] = ' '; |
5e3ca0ec IM |
422 | |
423 | return trace_seq_putmem(s, hex, j); | |
424 | } | |
425 | ||
e309b41d | 426 | static void |
214023c3 SR |
427 | trace_seq_reset(struct trace_seq *s) |
428 | { | |
429 | s->len = 0; | |
6c6c2796 PP |
430 | s->readpos = 0; |
431 | } | |
432 | ||
433 | ssize_t trace_seq_to_user(struct trace_seq *s, char __user *ubuf, size_t cnt) | |
434 | { | |
435 | int len; | |
436 | int ret; | |
437 | ||
438 | if (s->len <= s->readpos) | |
439 | return -EBUSY; | |
440 | ||
441 | len = s->len - s->readpos; | |
442 | if (cnt > len) | |
443 | cnt = len; | |
444 | ret = copy_to_user(ubuf, s->buffer + s->readpos, cnt); | |
445 | if (ret) | |
446 | return -EFAULT; | |
447 | ||
448 | s->readpos += len; | |
449 | return cnt; | |
214023c3 SR |
450 | } |
451 | ||
e309b41d | 452 | static void |
214023c3 SR |
453 | trace_print_seq(struct seq_file *m, struct trace_seq *s) |
454 | { | |
455 | int len = s->len >= PAGE_SIZE ? PAGE_SIZE - 1 : s->len; | |
456 | ||
457 | s->buffer[len] = 0; | |
458 | seq_puts(m, s->buffer); | |
459 | ||
460 | trace_seq_reset(s); | |
461 | } | |
462 | ||
4fcdae83 SR |
463 | /* |
464 | * flip the trace buffers between two trace descriptors. | |
465 | * This usually is the buffers between the global_trace and | |
466 | * the max_tr to record a snapshot of a current trace. | |
467 | * | |
468 | * The ftrace_max_lock must be held. | |
469 | */ | |
e309b41d | 470 | static void |
c7aafc54 IM |
471 | flip_trace(struct trace_array_cpu *tr1, struct trace_array_cpu *tr2) |
472 | { | |
473 | struct list_head flip_pages; | |
474 | ||
475 | INIT_LIST_HEAD(&flip_pages); | |
476 | ||
93a588f4 | 477 | memcpy(&tr1->trace_head_idx, &tr2->trace_head_idx, |
c7aafc54 | 478 | sizeof(struct trace_array_cpu) - |
93a588f4 | 479 | offsetof(struct trace_array_cpu, trace_head_idx)); |
c7aafc54 IM |
480 | |
481 | check_pages(tr1); | |
482 | check_pages(tr2); | |
483 | list_splice_init(&tr1->trace_pages, &flip_pages); | |
484 | list_splice_init(&tr2->trace_pages, &tr1->trace_pages); | |
485 | list_splice_init(&flip_pages, &tr2->trace_pages); | |
486 | BUG_ON(!list_empty(&flip_pages)); | |
487 | check_pages(tr1); | |
488 | check_pages(tr2); | |
489 | } | |
490 | ||
4fcdae83 SR |
491 | /** |
492 | * update_max_tr - snapshot all trace buffers from global_trace to max_tr | |
493 | * @tr: tracer | |
494 | * @tsk: the task with the latency | |
495 | * @cpu: The cpu that initiated the trace. | |
496 | * | |
497 | * Flip the buffers between the @tr and the max_tr and record information | |
498 | * about which task was the cause of this latency. | |
499 | */ | |
e309b41d | 500 | void |
bc0c38d1 SR |
501 | update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) |
502 | { | |
503 | struct trace_array_cpu *data; | |
bc0c38d1 SR |
504 | int i; |
505 | ||
4c11d7ae | 506 | WARN_ON_ONCE(!irqs_disabled()); |
92205c23 | 507 | __raw_spin_lock(&ftrace_max_lock); |
bc0c38d1 | 508 | /* clear out all the previous traces */ |
ab46428c | 509 | for_each_tracing_cpu(i) { |
bc0c38d1 | 510 | data = tr->data[i]; |
c7aafc54 | 511 | flip_trace(max_tr.data[i], data); |
89b2f978 | 512 | tracing_reset(data); |
bc0c38d1 SR |
513 | } |
514 | ||
515 | __update_max_tr(tr, tsk, cpu); | |
92205c23 | 516 | __raw_spin_unlock(&ftrace_max_lock); |
bc0c38d1 SR |
517 | } |
518 | ||
519 | /** | |
520 | * update_max_tr_single - only copy one trace over, and reset the rest | |
521 | * @tr - tracer | |
522 | * @tsk - task with the latency | |
523 | * @cpu - the cpu of the buffer to copy. | |
4fcdae83 SR |
524 | * |
525 | * Flip the trace of a single CPU buffer between the @tr and the max_tr. | |
bc0c38d1 | 526 | */ |
e309b41d | 527 | void |
bc0c38d1 SR |
528 | update_max_tr_single(struct trace_array *tr, struct task_struct *tsk, int cpu) |
529 | { | |
530 | struct trace_array_cpu *data = tr->data[cpu]; | |
bc0c38d1 SR |
531 | int i; |
532 | ||
4c11d7ae | 533 | WARN_ON_ONCE(!irqs_disabled()); |
92205c23 | 534 | __raw_spin_lock(&ftrace_max_lock); |
ab46428c | 535 | for_each_tracing_cpu(i) |
bc0c38d1 SR |
536 | tracing_reset(max_tr.data[i]); |
537 | ||
c7aafc54 | 538 | flip_trace(max_tr.data[cpu], data); |
89b2f978 | 539 | tracing_reset(data); |
bc0c38d1 SR |
540 | |
541 | __update_max_tr(tr, tsk, cpu); | |
92205c23 | 542 | __raw_spin_unlock(&ftrace_max_lock); |
bc0c38d1 SR |
543 | } |
544 | ||
4fcdae83 SR |
545 | /** |
546 | * register_tracer - register a tracer with the ftrace system. | |
547 | * @type - the plugin for the tracer | |
548 | * | |
549 | * Register a new plugin tracer. | |
550 | */ | |
bc0c38d1 SR |
551 | int register_tracer(struct tracer *type) |
552 | { | |
553 | struct tracer *t; | |
554 | int len; | |
555 | int ret = 0; | |
556 | ||
557 | if (!type->name) { | |
558 | pr_info("Tracer must have a name\n"); | |
559 | return -1; | |
560 | } | |
561 | ||
562 | mutex_lock(&trace_types_lock); | |
563 | for (t = trace_types; t; t = t->next) { | |
564 | if (strcmp(type->name, t->name) == 0) { | |
565 | /* already found */ | |
566 | pr_info("Trace %s already registered\n", | |
567 | type->name); | |
568 | ret = -1; | |
569 | goto out; | |
570 | } | |
571 | } | |
572 | ||
60a11774 SR |
573 | #ifdef CONFIG_FTRACE_STARTUP_TEST |
574 | if (type->selftest) { | |
575 | struct tracer *saved_tracer = current_trace; | |
576 | struct trace_array_cpu *data; | |
577 | struct trace_array *tr = &global_trace; | |
578 | int saved_ctrl = tr->ctrl; | |
579 | int i; | |
580 | /* | |
581 | * Run a selftest on this tracer. | |
582 | * Here we reset the trace buffer, and set the current | |
583 | * tracer to be this tracer. The tracer can then run some | |
584 | * internal tracing to verify that everything is in order. | |
585 | * If we fail, we do not register this tracer. | |
586 | */ | |
ab46428c | 587 | for_each_tracing_cpu(i) { |
60a11774 | 588 | data = tr->data[i]; |
c7aafc54 IM |
589 | if (!head_page(data)) |
590 | continue; | |
60a11774 SR |
591 | tracing_reset(data); |
592 | } | |
593 | current_trace = type; | |
594 | tr->ctrl = 0; | |
595 | /* the test is responsible for initializing and enabling */ | |
596 | pr_info("Testing tracer %s: ", type->name); | |
597 | ret = type->selftest(type, tr); | |
598 | /* the test is responsible for resetting too */ | |
599 | current_trace = saved_tracer; | |
600 | tr->ctrl = saved_ctrl; | |
601 | if (ret) { | |
602 | printk(KERN_CONT "FAILED!\n"); | |
603 | goto out; | |
604 | } | |
1d4db00a | 605 | /* Only reset on passing, to avoid touching corrupted buffers */ |
ab46428c | 606 | for_each_tracing_cpu(i) { |
1d4db00a SR |
607 | data = tr->data[i]; |
608 | if (!head_page(data)) | |
609 | continue; | |
610 | tracing_reset(data); | |
611 | } | |
60a11774 SR |
612 | printk(KERN_CONT "PASSED\n"); |
613 | } | |
614 | #endif | |
615 | ||
bc0c38d1 SR |
616 | type->next = trace_types; |
617 | trace_types = type; | |
618 | len = strlen(type->name); | |
619 | if (len > max_tracer_type_len) | |
620 | max_tracer_type_len = len; | |
60a11774 | 621 | |
bc0c38d1 SR |
622 | out: |
623 | mutex_unlock(&trace_types_lock); | |
624 | ||
625 | return ret; | |
626 | } | |
627 | ||
628 | void unregister_tracer(struct tracer *type) | |
629 | { | |
630 | struct tracer **t; | |
631 | int len; | |
632 | ||
633 | mutex_lock(&trace_types_lock); | |
634 | for (t = &trace_types; *t; t = &(*t)->next) { | |
635 | if (*t == type) | |
636 | goto found; | |
637 | } | |
638 | pr_info("Trace %s not registered\n", type->name); | |
639 | goto out; | |
640 | ||
641 | found: | |
642 | *t = (*t)->next; | |
643 | if (strlen(type->name) != max_tracer_type_len) | |
644 | goto out; | |
645 | ||
646 | max_tracer_type_len = 0; | |
647 | for (t = &trace_types; *t; t = &(*t)->next) { | |
648 | len = strlen((*t)->name); | |
649 | if (len > max_tracer_type_len) | |
650 | max_tracer_type_len = len; | |
651 | } | |
652 | out: | |
653 | mutex_unlock(&trace_types_lock); | |
654 | } | |
655 | ||
e309b41d | 656 | void tracing_reset(struct trace_array_cpu *data) |
bc0c38d1 SR |
657 | { |
658 | data->trace_idx = 0; | |
53d0aa77 | 659 | data->overrun = 0; |
93a588f4 SR |
660 | data->trace_head = data->trace_tail = head_page(data); |
661 | data->trace_head_idx = 0; | |
662 | data->trace_tail_idx = 0; | |
bc0c38d1 SR |
663 | } |
664 | ||
bc0c38d1 SR |
665 | #define SAVED_CMDLINES 128 |
666 | static unsigned map_pid_to_cmdline[PID_MAX_DEFAULT+1]; | |
667 | static unsigned map_cmdline_to_pid[SAVED_CMDLINES]; | |
668 | static char saved_cmdlines[SAVED_CMDLINES][TASK_COMM_LEN]; | |
669 | static int cmdline_idx; | |
670 | static DEFINE_SPINLOCK(trace_cmdline_lock); | |
25b0b44a | 671 | |
25b0b44a SR |
672 | /* temporary disable recording */ |
673 | atomic_t trace_record_cmdline_disabled __read_mostly; | |
bc0c38d1 SR |
674 | |
675 | static void trace_init_cmdlines(void) | |
676 | { | |
677 | memset(&map_pid_to_cmdline, -1, sizeof(map_pid_to_cmdline)); | |
678 | memset(&map_cmdline_to_pid, -1, sizeof(map_cmdline_to_pid)); | |
679 | cmdline_idx = 0; | |
680 | } | |
681 | ||
e309b41d | 682 | void trace_stop_cmdline_recording(void); |
bc0c38d1 | 683 | |
e309b41d | 684 | static void trace_save_cmdline(struct task_struct *tsk) |
bc0c38d1 SR |
685 | { |
686 | unsigned map; | |
687 | unsigned idx; | |
688 | ||
689 | if (!tsk->pid || unlikely(tsk->pid > PID_MAX_DEFAULT)) | |
690 | return; | |
691 | ||
692 | /* | |
693 | * It's not the end of the world if we don't get | |
694 | * the lock, but we also don't want to spin | |
695 | * nor do we want to disable interrupts, | |
696 | * so if we miss here, then better luck next time. | |
697 | */ | |
698 | if (!spin_trylock(&trace_cmdline_lock)) | |
699 | return; | |
700 | ||
701 | idx = map_pid_to_cmdline[tsk->pid]; | |
702 | if (idx >= SAVED_CMDLINES) { | |
703 | idx = (cmdline_idx + 1) % SAVED_CMDLINES; | |
704 | ||
705 | map = map_cmdline_to_pid[idx]; | |
706 | if (map <= PID_MAX_DEFAULT) | |
707 | map_pid_to_cmdline[map] = (unsigned)-1; | |
708 | ||
709 | map_pid_to_cmdline[tsk->pid] = idx; | |
710 | ||
711 | cmdline_idx = idx; | |
712 | } | |
713 | ||
714 | memcpy(&saved_cmdlines[idx], tsk->comm, TASK_COMM_LEN); | |
715 | ||
716 | spin_unlock(&trace_cmdline_lock); | |
717 | } | |
718 | ||
e309b41d | 719 | static char *trace_find_cmdline(int pid) |
bc0c38d1 SR |
720 | { |
721 | char *cmdline = "<...>"; | |
722 | unsigned map; | |
723 | ||
724 | if (!pid) | |
725 | return "<idle>"; | |
726 | ||
727 | if (pid > PID_MAX_DEFAULT) | |
728 | goto out; | |
729 | ||
730 | map = map_pid_to_cmdline[pid]; | |
731 | if (map >= SAVED_CMDLINES) | |
732 | goto out; | |
733 | ||
734 | cmdline = saved_cmdlines[map]; | |
735 | ||
736 | out: | |
737 | return cmdline; | |
738 | } | |
739 | ||
e309b41d | 740 | void tracing_record_cmdline(struct task_struct *tsk) |
bc0c38d1 SR |
741 | { |
742 | if (atomic_read(&trace_record_cmdline_disabled)) | |
743 | return; | |
744 | ||
745 | trace_save_cmdline(tsk); | |
746 | } | |
747 | ||
e309b41d | 748 | static inline struct list_head * |
93a588f4 SR |
749 | trace_next_list(struct trace_array_cpu *data, struct list_head *next) |
750 | { | |
751 | /* | |
752 | * Roundrobin - but skip the head (which is not a real page): | |
753 | */ | |
754 | next = next->next; | |
755 | if (unlikely(next == &data->trace_pages)) | |
756 | next = next->next; | |
757 | BUG_ON(next == &data->trace_pages); | |
758 | ||
759 | return next; | |
760 | } | |
761 | ||
e309b41d | 762 | static inline void * |
93a588f4 SR |
763 | trace_next_page(struct trace_array_cpu *data, void *addr) |
764 | { | |
765 | struct list_head *next; | |
766 | struct page *page; | |
767 | ||
768 | page = virt_to_page(addr); | |
769 | ||
770 | next = trace_next_list(data, &page->lru); | |
771 | page = list_entry(next, struct page, lru); | |
772 | ||
773 | return page_address(page); | |
774 | } | |
775 | ||
e309b41d | 776 | static inline struct trace_entry * |
c7aafc54 | 777 | tracing_get_trace_entry(struct trace_array *tr, struct trace_array_cpu *data) |
bc0c38d1 SR |
778 | { |
779 | unsigned long idx, idx_next; | |
780 | struct trace_entry *entry; | |
781 | ||
4c11d7ae | 782 | data->trace_idx++; |
93a588f4 | 783 | idx = data->trace_head_idx; |
bc0c38d1 SR |
784 | idx_next = idx + 1; |
785 | ||
c7aafc54 IM |
786 | BUG_ON(idx * TRACE_ENTRY_SIZE >= PAGE_SIZE); |
787 | ||
93a588f4 | 788 | entry = data->trace_head + idx * TRACE_ENTRY_SIZE; |
4c11d7ae SR |
789 | |
790 | if (unlikely(idx_next >= ENTRIES_PER_PAGE)) { | |
93a588f4 | 791 | data->trace_head = trace_next_page(data, data->trace_head); |
bc0c38d1 SR |
792 | idx_next = 0; |
793 | } | |
794 | ||
93a588f4 SR |
795 | if (data->trace_head == data->trace_tail && |
796 | idx_next == data->trace_tail_idx) { | |
797 | /* overrun */ | |
53d0aa77 | 798 | data->overrun++; |
93a588f4 SR |
799 | data->trace_tail_idx++; |
800 | if (data->trace_tail_idx >= ENTRIES_PER_PAGE) { | |
801 | data->trace_tail = | |
802 | trace_next_page(data, data->trace_tail); | |
803 | data->trace_tail_idx = 0; | |
804 | } | |
805 | } | |
806 | ||
807 | data->trace_head_idx = idx_next; | |
bc0c38d1 SR |
808 | |
809 | return entry; | |
810 | } | |
811 | ||
e309b41d | 812 | static inline void |
c7aafc54 | 813 | tracing_generic_entry_update(struct trace_entry *entry, unsigned long flags) |
bc0c38d1 SR |
814 | { |
815 | struct task_struct *tsk = current; | |
816 | unsigned long pc; | |
817 | ||
818 | pc = preempt_count(); | |
819 | ||
2e2ca155 SR |
820 | entry->field.preempt_count = pc & 0xff; |
821 | entry->field.pid = (tsk) ? tsk->pid : 0; | |
822 | entry->field.t = ftrace_now(raw_smp_processor_id()); | |
823 | entry->field.flags = | |
824 | (irqs_disabled_flags(flags) ? TRACE_FLAG_IRQS_OFF : 0) | | |
bc0c38d1 SR |
825 | ((pc & HARDIRQ_MASK) ? TRACE_FLAG_HARDIRQ : 0) | |
826 | ((pc & SOFTIRQ_MASK) ? TRACE_FLAG_SOFTIRQ : 0) | | |
827 | (need_resched() ? TRACE_FLAG_NEED_RESCHED : 0); | |
828 | } | |
829 | ||
e309b41d | 830 | void |
6fb44b71 SR |
831 | trace_function(struct trace_array *tr, struct trace_array_cpu *data, |
832 | unsigned long ip, unsigned long parent_ip, unsigned long flags) | |
bc0c38d1 SR |
833 | { |
834 | struct trace_entry *entry; | |
dcb6308f | 835 | unsigned long irq_flags; |
bc0c38d1 | 836 | |
92205c23 SR |
837 | raw_local_irq_save(irq_flags); |
838 | __raw_spin_lock(&data->lock); | |
2e2ca155 | 839 | entry = tracing_get_trace_entry(tr, data); |
bc0c38d1 | 840 | tracing_generic_entry_update(entry, flags); |
2e2ca155 SR |
841 | entry->type = TRACE_FN; |
842 | entry->field.fn.ip = ip; | |
843 | entry->field.fn.parent_ip = parent_ip; | |
92205c23 SR |
844 | __raw_spin_unlock(&data->lock); |
845 | raw_local_irq_restore(irq_flags); | |
bc0c38d1 SR |
846 | } |
847 | ||
e309b41d | 848 | void |
2e0f5761 IM |
849 | ftrace(struct trace_array *tr, struct trace_array_cpu *data, |
850 | unsigned long ip, unsigned long parent_ip, unsigned long flags) | |
851 | { | |
852 | if (likely(!atomic_read(&data->disabled))) | |
6fb44b71 | 853 | trace_function(tr, data, ip, parent_ip, flags); |
2e0f5761 IM |
854 | } |
855 | ||
bd8ac686 PP |
856 | #ifdef CONFIG_MMIOTRACE |
857 | void __trace_mmiotrace_rw(struct trace_array *tr, struct trace_array_cpu *data, | |
858 | struct mmiotrace_rw *rw) | |
859 | { | |
860 | struct trace_entry *entry; | |
861 | unsigned long irq_flags; | |
862 | ||
801a175b IM |
863 | raw_local_irq_save(irq_flags); |
864 | __raw_spin_lock(&data->lock); | |
865 | ||
2e2ca155 | 866 | entry = tracing_get_trace_entry(tr, data); |
bd8ac686 | 867 | tracing_generic_entry_update(entry, 0); |
2e2ca155 SR |
868 | entry->type = TRACE_MMIO_RW; |
869 | entry->field.mmiorw = *rw; | |
801a175b IM |
870 | |
871 | __raw_spin_unlock(&data->lock); | |
872 | raw_local_irq_restore(irq_flags); | |
bd8ac686 PP |
873 | |
874 | trace_wake_up(); | |
875 | } | |
876 | ||
877 | void __trace_mmiotrace_map(struct trace_array *tr, struct trace_array_cpu *data, | |
878 | struct mmiotrace_map *map) | |
879 | { | |
880 | struct trace_entry *entry; | |
881 | unsigned long irq_flags; | |
882 | ||
801a175b IM |
883 | raw_local_irq_save(irq_flags); |
884 | __raw_spin_lock(&data->lock); | |
885 | ||
2e2ca155 | 886 | entry = tracing_get_trace_entry(tr, data); |
bd8ac686 | 887 | tracing_generic_entry_update(entry, 0); |
2e2ca155 SR |
888 | entry->type = TRACE_MMIO_MAP; |
889 | entry->field.mmiomap = *map; | |
801a175b IM |
890 | |
891 | __raw_spin_unlock(&data->lock); | |
892 | raw_local_irq_restore(irq_flags); | |
bd8ac686 PP |
893 | |
894 | trace_wake_up(); | |
895 | } | |
896 | #endif | |
897 | ||
86387f7e IM |
898 | void __trace_stack(struct trace_array *tr, |
899 | struct trace_array_cpu *data, | |
900 | unsigned long flags, | |
901 | int skip) | |
902 | { | |
903 | struct trace_entry *entry; | |
904 | struct stack_trace trace; | |
905 | ||
906 | if (!(trace_flags & TRACE_ITER_STACKTRACE)) | |
907 | return; | |
908 | ||
909 | entry = tracing_get_trace_entry(tr, data); | |
910 | tracing_generic_entry_update(entry, flags); | |
911 | entry->type = TRACE_STACK; | |
912 | ||
2e2ca155 | 913 | memset(&entry->field.stack, 0, sizeof(entry->field.stack)); |
86387f7e IM |
914 | |
915 | trace.nr_entries = 0; | |
916 | trace.max_entries = FTRACE_STACK_ENTRIES; | |
917 | trace.skip = skip; | |
2e2ca155 | 918 | trace.entries = entry->field.stack.caller; |
86387f7e IM |
919 | |
920 | save_stack_trace(&trace); | |
f0a920d5 IM |
921 | } |
922 | ||
a4feb834 IM |
923 | void |
924 | __trace_special(void *__tr, void *__data, | |
925 | unsigned long arg1, unsigned long arg2, unsigned long arg3) | |
926 | { | |
927 | struct trace_array_cpu *data = __data; | |
928 | struct trace_array *tr = __tr; | |
929 | struct trace_entry *entry; | |
930 | unsigned long irq_flags; | |
931 | ||
932 | raw_local_irq_save(irq_flags); | |
933 | __raw_spin_lock(&data->lock); | |
2e2ca155 | 934 | entry = tracing_get_trace_entry(tr, data); |
a4feb834 | 935 | tracing_generic_entry_update(entry, 0); |
2e2ca155 SR |
936 | entry->type = TRACE_SPECIAL; |
937 | entry->field.special.arg1 = arg1; | |
938 | entry->field.special.arg2 = arg2; | |
939 | entry->field.special.arg3 = arg3; | |
a4feb834 IM |
940 | __trace_stack(tr, data, irq_flags, 4); |
941 | __raw_spin_unlock(&data->lock); | |
942 | raw_local_irq_restore(irq_flags); | |
943 | ||
944 | trace_wake_up(); | |
945 | } | |
946 | ||
e309b41d | 947 | void |
bc0c38d1 SR |
948 | tracing_sched_switch_trace(struct trace_array *tr, |
949 | struct trace_array_cpu *data, | |
86387f7e IM |
950 | struct task_struct *prev, |
951 | struct task_struct *next, | |
bc0c38d1 SR |
952 | unsigned long flags) |
953 | { | |
954 | struct trace_entry *entry; | |
dcb6308f | 955 | unsigned long irq_flags; |
bc0c38d1 | 956 | |
92205c23 SR |
957 | raw_local_irq_save(irq_flags); |
958 | __raw_spin_lock(&data->lock); | |
2e2ca155 | 959 | entry = tracing_get_trace_entry(tr, data); |
bc0c38d1 | 960 | tracing_generic_entry_update(entry, flags); |
2e2ca155 SR |
961 | entry->type = TRACE_CTX; |
962 | entry->field.ctx.prev_pid = prev->pid; | |
963 | entry->field.ctx.prev_prio = prev->prio; | |
964 | entry->field.ctx.prev_state = prev->state; | |
965 | entry->field.ctx.next_pid = next->pid; | |
966 | entry->field.ctx.next_prio = next->prio; | |
967 | entry->field.ctx.next_state = next->state; | |
74f4e369 | 968 | __trace_stack(tr, data, flags, 5); |
92205c23 SR |
969 | __raw_spin_unlock(&data->lock); |
970 | raw_local_irq_restore(irq_flags); | |
bc0c38d1 SR |
971 | } |
972 | ||
57422797 IM |
973 | void |
974 | tracing_sched_wakeup_trace(struct trace_array *tr, | |
975 | struct trace_array_cpu *data, | |
86387f7e IM |
976 | struct task_struct *wakee, |
977 | struct task_struct *curr, | |
57422797 IM |
978 | unsigned long flags) |
979 | { | |
980 | struct trace_entry *entry; | |
981 | unsigned long irq_flags; | |
982 | ||
92205c23 SR |
983 | raw_local_irq_save(irq_flags); |
984 | __raw_spin_lock(&data->lock); | |
57422797 IM |
985 | entry = tracing_get_trace_entry(tr, data); |
986 | tracing_generic_entry_update(entry, flags); | |
987 | entry->type = TRACE_WAKE; | |
2e2ca155 SR |
988 | entry->field.ctx.prev_pid = curr->pid; |
989 | entry->field.ctx.prev_prio = curr->prio; | |
990 | entry->field.ctx.prev_state = curr->state; | |
991 | entry->field.ctx.next_pid = wakee->pid; | |
992 | entry->field.ctx.next_prio = wakee->prio; | |
993 | entry->field.ctx.next_state = wakee->state; | |
74f4e369 | 994 | __trace_stack(tr, data, flags, 6); |
92205c23 SR |
995 | __raw_spin_unlock(&data->lock); |
996 | raw_local_irq_restore(irq_flags); | |
017730c1 IM |
997 | |
998 | trace_wake_up(); | |
57422797 IM |
999 | } |
1000 | ||
4902f884 SR |
1001 | void |
1002 | ftrace_special(unsigned long arg1, unsigned long arg2, unsigned long arg3) | |
1003 | { | |
1004 | struct trace_array *tr = &global_trace; | |
1005 | struct trace_array_cpu *data; | |
1006 | unsigned long flags; | |
1007 | long disabled; | |
1008 | int cpu; | |
1009 | ||
1010 | if (tracing_disabled || current_trace == &no_tracer || !tr->ctrl) | |
1011 | return; | |
1012 | ||
1013 | local_irq_save(flags); | |
1014 | cpu = raw_smp_processor_id(); | |
1015 | data = tr->data[cpu]; | |
1016 | disabled = atomic_inc_return(&data->disabled); | |
1017 | ||
1018 | if (likely(disabled == 1)) | |
1019 | __trace_special(tr, data, arg1, arg2, arg3); | |
1020 | ||
1021 | atomic_dec(&data->disabled); | |
1022 | local_irq_restore(flags); | |
1023 | } | |
1024 | ||
2e0f5761 | 1025 | #ifdef CONFIG_FTRACE |
e309b41d | 1026 | static void |
2e0f5761 IM |
1027 | function_trace_call(unsigned long ip, unsigned long parent_ip) |
1028 | { | |
1029 | struct trace_array *tr = &global_trace; | |
1030 | struct trace_array_cpu *data; | |
1031 | unsigned long flags; | |
1032 | long disabled; | |
1033 | int cpu; | |
1034 | ||
60bc0800 | 1035 | if (unlikely(!ftrace_function_enabled)) |
2e0f5761 IM |
1036 | return; |
1037 | ||
ecea656d AS |
1038 | if (skip_trace(ip)) |
1039 | return; | |
1040 | ||
2e0f5761 IM |
1041 | local_irq_save(flags); |
1042 | cpu = raw_smp_processor_id(); | |
1043 | data = tr->data[cpu]; | |
1044 | disabled = atomic_inc_return(&data->disabled); | |
1045 | ||
1046 | if (likely(disabled == 1)) | |
6fb44b71 | 1047 | trace_function(tr, data, ip, parent_ip, flags); |
2e0f5761 IM |
1048 | |
1049 | atomic_dec(&data->disabled); | |
1050 | local_irq_restore(flags); | |
1051 | } | |
1052 | ||
1053 | static struct ftrace_ops trace_ops __read_mostly = | |
1054 | { | |
1055 | .func = function_trace_call, | |
1056 | }; | |
1057 | ||
e309b41d | 1058 | void tracing_start_function_trace(void) |
2e0f5761 | 1059 | { |
60bc0800 | 1060 | ftrace_function_enabled = 0; |
2e0f5761 | 1061 | register_ftrace_function(&trace_ops); |
60bc0800 SR |
1062 | if (tracer_enabled) |
1063 | ftrace_function_enabled = 1; | |
2e0f5761 IM |
1064 | } |
1065 | ||
e309b41d | 1066 | void tracing_stop_function_trace(void) |
2e0f5761 | 1067 | { |
60bc0800 | 1068 | ftrace_function_enabled = 0; |
2e0f5761 IM |
1069 | unregister_ftrace_function(&trace_ops); |
1070 | } | |
1071 | #endif | |
1072 | ||
bc0c38d1 SR |
1073 | enum trace_file_type { |
1074 | TRACE_FILE_LAT_FMT = 1, | |
1075 | }; | |
1076 | ||
1077 | static struct trace_entry * | |
4c11d7ae SR |
1078 | trace_entry_idx(struct trace_array *tr, struct trace_array_cpu *data, |
1079 | struct trace_iterator *iter, int cpu) | |
bc0c38d1 | 1080 | { |
4c11d7ae SR |
1081 | struct page *page; |
1082 | struct trace_entry *array; | |
bc0c38d1 | 1083 | |
4c11d7ae | 1084 | if (iter->next_idx[cpu] >= tr->entries || |
b3806b43 SR |
1085 | iter->next_idx[cpu] >= data->trace_idx || |
1086 | (data->trace_head == data->trace_tail && | |
1087 | data->trace_head_idx == data->trace_tail_idx)) | |
bc0c38d1 SR |
1088 | return NULL; |
1089 | ||
4c11d7ae | 1090 | if (!iter->next_page[cpu]) { |
93a588f4 SR |
1091 | /* Initialize the iterator for this cpu trace buffer */ |
1092 | WARN_ON(!data->trace_tail); | |
1093 | page = virt_to_page(data->trace_tail); | |
1094 | iter->next_page[cpu] = &page->lru; | |
1095 | iter->next_page_idx[cpu] = data->trace_tail_idx; | |
4c11d7ae | 1096 | } |
bc0c38d1 | 1097 | |
4c11d7ae | 1098 | page = list_entry(iter->next_page[cpu], struct page, lru); |
c7aafc54 IM |
1099 | BUG_ON(&data->trace_pages == &page->lru); |
1100 | ||
4c11d7ae SR |
1101 | array = page_address(page); |
1102 | ||
93a588f4 | 1103 | WARN_ON(iter->next_page_idx[cpu] >= ENTRIES_PER_PAGE); |
4c11d7ae | 1104 | return &array[iter->next_page_idx[cpu]]; |
bc0c38d1 SR |
1105 | } |
1106 | ||
e309b41d | 1107 | static struct trace_entry * |
bc0c38d1 SR |
1108 | find_next_entry(struct trace_iterator *iter, int *ent_cpu) |
1109 | { | |
1110 | struct trace_array *tr = iter->tr; | |
1111 | struct trace_entry *ent, *next = NULL; | |
1112 | int next_cpu = -1; | |
1113 | int cpu; | |
1114 | ||
ab46428c | 1115 | for_each_tracing_cpu(cpu) { |
c7aafc54 | 1116 | if (!head_page(tr->data[cpu])) |
bc0c38d1 | 1117 | continue; |
4c11d7ae | 1118 | ent = trace_entry_idx(tr, tr->data[cpu], iter, cpu); |
cdd31cd2 IM |
1119 | /* |
1120 | * Pick the entry with the smallest timestamp: | |
1121 | */ | |
2e2ca155 | 1122 | if (ent && (!next || ent->field.t < next->field.t)) { |
bc0c38d1 SR |
1123 | next = ent; |
1124 | next_cpu = cpu; | |
1125 | } | |
1126 | } | |
1127 | ||
1128 | if (ent_cpu) | |
1129 | *ent_cpu = next_cpu; | |
1130 | ||
1131 | return next; | |
1132 | } | |
1133 | ||
e309b41d | 1134 | static void trace_iterator_increment(struct trace_iterator *iter) |
bc0c38d1 | 1135 | { |
b3806b43 SR |
1136 | iter->idx++; |
1137 | iter->next_idx[iter->cpu]++; | |
1138 | iter->next_page_idx[iter->cpu]++; | |
8c523a9d | 1139 | |
b3806b43 SR |
1140 | if (iter->next_page_idx[iter->cpu] >= ENTRIES_PER_PAGE) { |
1141 | struct trace_array_cpu *data = iter->tr->data[iter->cpu]; | |
bc0c38d1 | 1142 | |
b3806b43 SR |
1143 | iter->next_page_idx[iter->cpu] = 0; |
1144 | iter->next_page[iter->cpu] = | |
1145 | trace_next_list(data, iter->next_page[iter->cpu]); | |
1146 | } | |
1147 | } | |
bc0c38d1 | 1148 | |
e309b41d | 1149 | static void trace_consume(struct trace_iterator *iter) |
b3806b43 SR |
1150 | { |
1151 | struct trace_array_cpu *data = iter->tr->data[iter->cpu]; | |
1152 | ||
1153 | data->trace_tail_idx++; | |
1154 | if (data->trace_tail_idx >= ENTRIES_PER_PAGE) { | |
1155 | data->trace_tail = trace_next_page(data, data->trace_tail); | |
1156 | data->trace_tail_idx = 0; | |
1157 | } | |
4e3c3333 | 1158 | |
b3806b43 SR |
1159 | /* Check if we empty it, then reset the index */ |
1160 | if (data->trace_head == data->trace_tail && | |
1161 | data->trace_head_idx == data->trace_tail_idx) | |
1162 | data->trace_idx = 0; | |
b3806b43 SR |
1163 | } |
1164 | ||
e309b41d | 1165 | static void *find_next_entry_inc(struct trace_iterator *iter) |
b3806b43 SR |
1166 | { |
1167 | struct trace_entry *next; | |
1168 | int next_cpu = -1; | |
1169 | ||
1170 | next = find_next_entry(iter, &next_cpu); | |
93a588f4 | 1171 | |
4e3c3333 IM |
1172 | iter->prev_ent = iter->ent; |
1173 | iter->prev_cpu = iter->cpu; | |
1174 | ||
bc0c38d1 SR |
1175 | iter->ent = next; |
1176 | iter->cpu = next_cpu; | |
1177 | ||
b3806b43 SR |
1178 | if (next) |
1179 | trace_iterator_increment(iter); | |
1180 | ||
bc0c38d1 SR |
1181 | return next ? iter : NULL; |
1182 | } | |
1183 | ||
e309b41d | 1184 | static void *s_next(struct seq_file *m, void *v, loff_t *pos) |
bc0c38d1 SR |
1185 | { |
1186 | struct trace_iterator *iter = m->private; | |
bc0c38d1 | 1187 | int i = (int)*pos; |
4e3c3333 | 1188 | void *ent; |
bc0c38d1 SR |
1189 | |
1190 | (*pos)++; | |
1191 | ||
1192 | /* can't go backwards */ | |
1193 | if (iter->idx > i) | |
1194 | return NULL; | |
1195 | ||
1196 | if (iter->idx < 0) | |
1197 | ent = find_next_entry_inc(iter); | |
1198 | else | |
1199 | ent = iter; | |
1200 | ||
1201 | while (ent && iter->idx < i) | |
1202 | ent = find_next_entry_inc(iter); | |
1203 | ||
1204 | iter->pos = *pos; | |
1205 | ||
bc0c38d1 SR |
1206 | return ent; |
1207 | } | |
1208 | ||
1209 | static void *s_start(struct seq_file *m, loff_t *pos) | |
1210 | { | |
1211 | struct trace_iterator *iter = m->private; | |
1212 | void *p = NULL; | |
1213 | loff_t l = 0; | |
1214 | int i; | |
1215 | ||
1216 | mutex_lock(&trace_types_lock); | |
1217 | ||
d15f57f2 SR |
1218 | if (!current_trace || current_trace != iter->trace) { |
1219 | mutex_unlock(&trace_types_lock); | |
bc0c38d1 | 1220 | return NULL; |
d15f57f2 | 1221 | } |
bc0c38d1 SR |
1222 | |
1223 | atomic_inc(&trace_record_cmdline_disabled); | |
1224 | ||
1225 | /* let the tracer grab locks here if needed */ | |
1226 | if (current_trace->start) | |
1227 | current_trace->start(iter); | |
1228 | ||
1229 | if (*pos != iter->pos) { | |
1230 | iter->ent = NULL; | |
1231 | iter->cpu = 0; | |
1232 | iter->idx = -1; | |
4e3c3333 IM |
1233 | iter->prev_ent = NULL; |
1234 | iter->prev_cpu = -1; | |
bc0c38d1 | 1235 | |
ab46428c | 1236 | for_each_tracing_cpu(i) { |
bc0c38d1 | 1237 | iter->next_idx[i] = 0; |
4c11d7ae SR |
1238 | iter->next_page[i] = NULL; |
1239 | } | |
bc0c38d1 SR |
1240 | |
1241 | for (p = iter; p && l < *pos; p = s_next(m, p, &l)) | |
1242 | ; | |
1243 | ||
1244 | } else { | |
4c11d7ae | 1245 | l = *pos - 1; |
bc0c38d1 SR |
1246 | p = s_next(m, p, &l); |
1247 | } | |
1248 | ||
1249 | return p; | |
1250 | } | |
1251 | ||
1252 | static void s_stop(struct seq_file *m, void *p) | |
1253 | { | |
1254 | struct trace_iterator *iter = m->private; | |
1255 | ||
1256 | atomic_dec(&trace_record_cmdline_disabled); | |
1257 | ||
1258 | /* let the tracer release locks here if needed */ | |
1259 | if (current_trace && current_trace == iter->trace && iter->trace->stop) | |
1260 | iter->trace->stop(iter); | |
1261 | ||
1262 | mutex_unlock(&trace_types_lock); | |
1263 | } | |
1264 | ||
76094a2c AS |
1265 | #define KRETPROBE_MSG "[unknown/kretprobe'd]" |
1266 | ||
1267 | #ifdef CONFIG_KRETPROBES | |
1268 | static inline int kretprobed(unsigned long addr) | |
1269 | { | |
1270 | return addr == (unsigned long)kretprobe_trampoline; | |
1271 | } | |
1272 | #else | |
1273 | static inline int kretprobed(unsigned long addr) | |
1274 | { | |
1275 | return 0; | |
1276 | } | |
1277 | #endif /* CONFIG_KRETPROBES */ | |
1278 | ||
b3806b43 | 1279 | static int |
214023c3 | 1280 | seq_print_sym_short(struct trace_seq *s, const char *fmt, unsigned long address) |
bc0c38d1 SR |
1281 | { |
1282 | #ifdef CONFIG_KALLSYMS | |
1283 | char str[KSYM_SYMBOL_LEN]; | |
1284 | ||
1285 | kallsyms_lookup(address, NULL, NULL, NULL, str); | |
1286 | ||
b3806b43 | 1287 | return trace_seq_printf(s, fmt, str); |
bc0c38d1 | 1288 | #endif |
b3806b43 | 1289 | return 1; |
bc0c38d1 SR |
1290 | } |
1291 | ||
b3806b43 | 1292 | static int |
214023c3 SR |
1293 | seq_print_sym_offset(struct trace_seq *s, const char *fmt, |
1294 | unsigned long address) | |
bc0c38d1 SR |
1295 | { |
1296 | #ifdef CONFIG_KALLSYMS | |
1297 | char str[KSYM_SYMBOL_LEN]; | |
1298 | ||
1299 | sprint_symbol(str, address); | |
b3806b43 | 1300 | return trace_seq_printf(s, fmt, str); |
bc0c38d1 | 1301 | #endif |
b3806b43 | 1302 | return 1; |
bc0c38d1 SR |
1303 | } |
1304 | ||
1305 | #ifndef CONFIG_64BIT | |
1306 | # define IP_FMT "%08lx" | |
1307 | #else | |
1308 | # define IP_FMT "%016lx" | |
1309 | #endif | |
1310 | ||
e309b41d | 1311 | static int |
214023c3 | 1312 | seq_print_ip_sym(struct trace_seq *s, unsigned long ip, unsigned long sym_flags) |
bc0c38d1 | 1313 | { |
b3806b43 SR |
1314 | int ret; |
1315 | ||
1316 | if (!ip) | |
1317 | return trace_seq_printf(s, "0"); | |
bc0c38d1 SR |
1318 | |
1319 | if (sym_flags & TRACE_ITER_SYM_OFFSET) | |
b3806b43 | 1320 | ret = seq_print_sym_offset(s, "%s", ip); |
bc0c38d1 | 1321 | else |
b3806b43 SR |
1322 | ret = seq_print_sym_short(s, "%s", ip); |
1323 | ||
1324 | if (!ret) | |
1325 | return 0; | |
bc0c38d1 SR |
1326 | |
1327 | if (sym_flags & TRACE_ITER_SYM_ADDR) | |
b3806b43 SR |
1328 | ret = trace_seq_printf(s, " <" IP_FMT ">", ip); |
1329 | return ret; | |
bc0c38d1 SR |
1330 | } |
1331 | ||
e309b41d | 1332 | static void print_lat_help_header(struct seq_file *m) |
bc0c38d1 SR |
1333 | { |
1334 | seq_puts(m, "# _------=> CPU# \n"); | |
1335 | seq_puts(m, "# / _-----=> irqs-off \n"); | |
1336 | seq_puts(m, "# | / _----=> need-resched \n"); | |
1337 | seq_puts(m, "# || / _---=> hardirq/softirq \n"); | |
1338 | seq_puts(m, "# ||| / _--=> preempt-depth \n"); | |
1339 | seq_puts(m, "# |||| / \n"); | |
1340 | seq_puts(m, "# ||||| delay \n"); | |
1341 | seq_puts(m, "# cmd pid ||||| time | caller \n"); | |
1342 | seq_puts(m, "# \\ / ||||| \\ | / \n"); | |
1343 | } | |
1344 | ||
e309b41d | 1345 | static void print_func_help_header(struct seq_file *m) |
bc0c38d1 SR |
1346 | { |
1347 | seq_puts(m, "# TASK-PID CPU# TIMESTAMP FUNCTION\n"); | |
1348 | seq_puts(m, "# | | | | |\n"); | |
1349 | } | |
1350 | ||
1351 | ||
e309b41d | 1352 | static void |
bc0c38d1 SR |
1353 | print_trace_header(struct seq_file *m, struct trace_iterator *iter) |
1354 | { | |
1355 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); | |
1356 | struct trace_array *tr = iter->tr; | |
1357 | struct trace_array_cpu *data = tr->data[tr->cpu]; | |
1358 | struct tracer *type = current_trace; | |
4c11d7ae SR |
1359 | unsigned long total = 0; |
1360 | unsigned long entries = 0; | |
bc0c38d1 SR |
1361 | int cpu; |
1362 | const char *name = "preemption"; | |
1363 | ||
1364 | if (type) | |
1365 | name = type->name; | |
1366 | ||
ab46428c | 1367 | for_each_tracing_cpu(cpu) { |
c7aafc54 | 1368 | if (head_page(tr->data[cpu])) { |
4c11d7ae SR |
1369 | total += tr->data[cpu]->trace_idx; |
1370 | if (tr->data[cpu]->trace_idx > tr->entries) | |
bc0c38d1 | 1371 | entries += tr->entries; |
4c11d7ae | 1372 | else |
bc0c38d1 SR |
1373 | entries += tr->data[cpu]->trace_idx; |
1374 | } | |
1375 | } | |
1376 | ||
1377 | seq_printf(m, "%s latency trace v1.1.5 on %s\n", | |
1378 | name, UTS_RELEASE); | |
1379 | seq_puts(m, "-----------------------------------" | |
1380 | "---------------------------------\n"); | |
1381 | seq_printf(m, " latency: %lu us, #%lu/%lu, CPU#%d |" | |
1382 | " (M:%s VP:%d, KP:%d, SP:%d HP:%d", | |
57f50be1 | 1383 | nsecs_to_usecs(data->saved_latency), |
bc0c38d1 | 1384 | entries, |
4c11d7ae | 1385 | total, |
bc0c38d1 SR |
1386 | tr->cpu, |
1387 | #if defined(CONFIG_PREEMPT_NONE) | |
1388 | "server", | |
1389 | #elif defined(CONFIG_PREEMPT_VOLUNTARY) | |
1390 | "desktop", | |
b5c21b45 | 1391 | #elif defined(CONFIG_PREEMPT) |
bc0c38d1 SR |
1392 | "preempt", |
1393 | #else | |
1394 | "unknown", | |
1395 | #endif | |
1396 | /* These are reserved for later use */ | |
1397 | 0, 0, 0, 0); | |
1398 | #ifdef CONFIG_SMP | |
1399 | seq_printf(m, " #P:%d)\n", num_online_cpus()); | |
1400 | #else | |
1401 | seq_puts(m, ")\n"); | |
1402 | #endif | |
1403 | seq_puts(m, " -----------------\n"); | |
1404 | seq_printf(m, " | task: %.16s-%d " | |
1405 | "(uid:%d nice:%ld policy:%ld rt_prio:%ld)\n", | |
1406 | data->comm, data->pid, data->uid, data->nice, | |
1407 | data->policy, data->rt_priority); | |
1408 | seq_puts(m, " -----------------\n"); | |
1409 | ||
1410 | if (data->critical_start) { | |
1411 | seq_puts(m, " => started at: "); | |
214023c3 SR |
1412 | seq_print_ip_sym(&iter->seq, data->critical_start, sym_flags); |
1413 | trace_print_seq(m, &iter->seq); | |
bc0c38d1 | 1414 | seq_puts(m, "\n => ended at: "); |
214023c3 SR |
1415 | seq_print_ip_sym(&iter->seq, data->critical_end, sym_flags); |
1416 | trace_print_seq(m, &iter->seq); | |
bc0c38d1 SR |
1417 | seq_puts(m, "\n"); |
1418 | } | |
1419 | ||
1420 | seq_puts(m, "\n"); | |
1421 | } | |
1422 | ||
e309b41d | 1423 | static void |
214023c3 | 1424 | lat_print_generic(struct trace_seq *s, struct trace_entry *entry, int cpu) |
bc0c38d1 | 1425 | { |
2e2ca155 | 1426 | struct trace_field *field = &entry->field; |
bc0c38d1 SR |
1427 | int hardirq, softirq; |
1428 | char *comm; | |
1429 | ||
2e2ca155 | 1430 | comm = trace_find_cmdline(field->pid); |
bc0c38d1 | 1431 | |
2e2ca155 | 1432 | trace_seq_printf(s, "%8.8s-%-5d ", comm, field->pid); |
214023c3 SR |
1433 | trace_seq_printf(s, "%d", cpu); |
1434 | trace_seq_printf(s, "%c%c", | |
2e2ca155 SR |
1435 | (field->flags & TRACE_FLAG_IRQS_OFF) ? 'd' : '.', |
1436 | ((field->flags & TRACE_FLAG_NEED_RESCHED) ? 'N' : '.')); | |
bc0c38d1 | 1437 | |
2e2ca155 SR |
1438 | hardirq = field->flags & TRACE_FLAG_HARDIRQ; |
1439 | softirq = field->flags & TRACE_FLAG_SOFTIRQ; | |
afc2abc0 | 1440 | if (hardirq && softirq) { |
214023c3 | 1441 | trace_seq_putc(s, 'H'); |
afc2abc0 IM |
1442 | } else { |
1443 | if (hardirq) { | |
214023c3 | 1444 | trace_seq_putc(s, 'h'); |
afc2abc0 | 1445 | } else { |
bc0c38d1 | 1446 | if (softirq) |
214023c3 | 1447 | trace_seq_putc(s, 's'); |
bc0c38d1 | 1448 | else |
214023c3 | 1449 | trace_seq_putc(s, '.'); |
bc0c38d1 SR |
1450 | } |
1451 | } | |
1452 | ||
2e2ca155 SR |
1453 | if (field->preempt_count) |
1454 | trace_seq_printf(s, "%x", field->preempt_count); | |
bc0c38d1 | 1455 | else |
214023c3 | 1456 | trace_seq_puts(s, "."); |
bc0c38d1 SR |
1457 | } |
1458 | ||
1459 | unsigned long preempt_mark_thresh = 100; | |
1460 | ||
e309b41d | 1461 | static void |
214023c3 | 1462 | lat_print_timestamp(struct trace_seq *s, unsigned long long abs_usecs, |
bc0c38d1 SR |
1463 | unsigned long rel_usecs) |
1464 | { | |
214023c3 | 1465 | trace_seq_printf(s, " %4lldus", abs_usecs); |
bc0c38d1 | 1466 | if (rel_usecs > preempt_mark_thresh) |
214023c3 | 1467 | trace_seq_puts(s, "!: "); |
bc0c38d1 | 1468 | else if (rel_usecs > 1) |
214023c3 | 1469 | trace_seq_puts(s, "+: "); |
bc0c38d1 | 1470 | else |
214023c3 | 1471 | trace_seq_puts(s, " : "); |
bc0c38d1 SR |
1472 | } |
1473 | ||
1474 | static const char state_to_char[] = TASK_STATE_TO_CHAR_STR; | |
1475 | ||
e309b41d | 1476 | static int |
214023c3 | 1477 | print_lat_fmt(struct trace_iterator *iter, unsigned int trace_idx, int cpu) |
bc0c38d1 | 1478 | { |
214023c3 | 1479 | struct trace_seq *s = &iter->seq; |
bc0c38d1 SR |
1480 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); |
1481 | struct trace_entry *next_entry = find_next_entry(iter, NULL); | |
1482 | unsigned long verbose = (trace_flags & TRACE_ITER_VERBOSE); | |
1483 | struct trace_entry *entry = iter->ent; | |
2e2ca155 | 1484 | struct trace_field *field = &entry->field; |
bc0c38d1 SR |
1485 | unsigned long abs_usecs; |
1486 | unsigned long rel_usecs; | |
1487 | char *comm; | |
bac524d3 | 1488 | int S, T; |
86387f7e | 1489 | int i; |
d17d9691 | 1490 | unsigned state; |
bc0c38d1 SR |
1491 | |
1492 | if (!next_entry) | |
1493 | next_entry = entry; | |
2e2ca155 SR |
1494 | rel_usecs = ns2usecs(next_entry->field.t - entry->field.t); |
1495 | abs_usecs = ns2usecs(entry->field.t - iter->tr->time_start); | |
bc0c38d1 SR |
1496 | |
1497 | if (verbose) { | |
2e2ca155 | 1498 | comm = trace_find_cmdline(field->pid); |
214023c3 SR |
1499 | trace_seq_printf(s, "%16s %5d %d %d %08x %08x [%08lx]" |
1500 | " %ld.%03ldms (+%ld.%03ldms): ", | |
1501 | comm, | |
2e2ca155 SR |
1502 | field->pid, cpu, field->flags, |
1503 | field->preempt_count, trace_idx, | |
1504 | ns2usecs(field->t), | |
214023c3 SR |
1505 | abs_usecs/1000, |
1506 | abs_usecs % 1000, rel_usecs/1000, | |
1507 | rel_usecs % 1000); | |
bc0c38d1 | 1508 | } else { |
f29c73fe IM |
1509 | lat_print_generic(s, entry, cpu); |
1510 | lat_print_timestamp(s, abs_usecs, rel_usecs); | |
bc0c38d1 SR |
1511 | } |
1512 | switch (entry->type) { | |
1513 | case TRACE_FN: | |
2e2ca155 | 1514 | seq_print_ip_sym(s, field->fn.ip, sym_flags); |
214023c3 | 1515 | trace_seq_puts(s, " ("); |
2e2ca155 | 1516 | if (kretprobed(field->fn.parent_ip)) |
76094a2c AS |
1517 | trace_seq_puts(s, KRETPROBE_MSG); |
1518 | else | |
2e2ca155 | 1519 | seq_print_ip_sym(s, field->fn.parent_ip, sym_flags); |
214023c3 | 1520 | trace_seq_puts(s, ")\n"); |
bc0c38d1 SR |
1521 | break; |
1522 | case TRACE_CTX: | |
57422797 | 1523 | case TRACE_WAKE: |
2e2ca155 SR |
1524 | T = field->ctx.next_state < sizeof(state_to_char) ? |
1525 | state_to_char[field->ctx.next_state] : 'X'; | |
bac524d3 | 1526 | |
2e2ca155 SR |
1527 | state = field->ctx.prev_state ? |
1528 | __ffs(field->ctx.prev_state) + 1 : 0; | |
d17d9691 | 1529 | S = state < sizeof(state_to_char) - 1 ? state_to_char[state] : 'X'; |
2e2ca155 | 1530 | comm = trace_find_cmdline(field->ctx.next_pid); |
bac524d3 | 1531 | trace_seq_printf(s, " %5d:%3d:%c %s %5d:%3d:%c %s\n", |
2e2ca155 SR |
1532 | field->ctx.prev_pid, |
1533 | field->ctx.prev_prio, | |
57422797 | 1534 | S, entry->type == TRACE_CTX ? "==>" : " +", |
2e2ca155 SR |
1535 | field->ctx.next_pid, |
1536 | field->ctx.next_prio, | |
bac524d3 | 1537 | T, comm); |
bc0c38d1 | 1538 | break; |
f0a920d5 | 1539 | case TRACE_SPECIAL: |
88a4216c | 1540 | trace_seq_printf(s, "# %ld %ld %ld\n", |
2e2ca155 SR |
1541 | field->special.arg1, |
1542 | field->special.arg2, | |
1543 | field->special.arg3); | |
f0a920d5 | 1544 | break; |
86387f7e IM |
1545 | case TRACE_STACK: |
1546 | for (i = 0; i < FTRACE_STACK_ENTRIES; i++) { | |
1547 | if (i) | |
1548 | trace_seq_puts(s, " <= "); | |
2e2ca155 | 1549 | seq_print_ip_sym(s, field->stack.caller[i], sym_flags); |
86387f7e IM |
1550 | } |
1551 | trace_seq_puts(s, "\n"); | |
1552 | break; | |
89b2f978 | 1553 | default: |
214023c3 | 1554 | trace_seq_printf(s, "Unknown type %d\n", entry->type); |
bc0c38d1 | 1555 | } |
f9896bf3 | 1556 | return 1; |
bc0c38d1 SR |
1557 | } |
1558 | ||
e309b41d | 1559 | static int print_trace_fmt(struct trace_iterator *iter) |
bc0c38d1 | 1560 | { |
214023c3 | 1561 | struct trace_seq *s = &iter->seq; |
bc0c38d1 | 1562 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); |
4e3c3333 | 1563 | struct trace_entry *entry; |
2e2ca155 | 1564 | struct trace_field *field; |
bc0c38d1 SR |
1565 | unsigned long usec_rem; |
1566 | unsigned long long t; | |
1567 | unsigned long secs; | |
1568 | char *comm; | |
b3806b43 | 1569 | int ret; |
bac524d3 | 1570 | int S, T; |
86387f7e | 1571 | int i; |
bc0c38d1 | 1572 | |
4e3c3333 | 1573 | entry = iter->ent; |
2e2ca155 | 1574 | field = &entry->field; |
4e3c3333 | 1575 | |
2e2ca155 | 1576 | comm = trace_find_cmdline(iter->ent->field.pid); |
bc0c38d1 | 1577 | |
2e2ca155 | 1578 | t = ns2usecs(field->t); |
bc0c38d1 SR |
1579 | usec_rem = do_div(t, 1000000ULL); |
1580 | secs = (unsigned long)t; | |
1581 | ||
2e2ca155 | 1582 | ret = trace_seq_printf(s, "%16s-%-5d ", comm, field->pid); |
f29c73fe IM |
1583 | if (!ret) |
1584 | return 0; | |
1585 | ret = trace_seq_printf(s, "[%02d] ", iter->cpu); | |
1586 | if (!ret) | |
1587 | return 0; | |
1588 | ret = trace_seq_printf(s, "%5lu.%06lu: ", secs, usec_rem); | |
1589 | if (!ret) | |
1590 | return 0; | |
bc0c38d1 SR |
1591 | |
1592 | switch (entry->type) { | |
1593 | case TRACE_FN: | |
2e2ca155 | 1594 | ret = seq_print_ip_sym(s, field->fn.ip, sym_flags); |
b3806b43 SR |
1595 | if (!ret) |
1596 | return 0; | |
bc0c38d1 | 1597 | if ((sym_flags & TRACE_ITER_PRINT_PARENT) && |
2e2ca155 | 1598 | field->fn.parent_ip) { |
b3806b43 SR |
1599 | ret = trace_seq_printf(s, " <-"); |
1600 | if (!ret) | |
1601 | return 0; | |
2e2ca155 | 1602 | if (kretprobed(field->fn.parent_ip)) |
76094a2c AS |
1603 | ret = trace_seq_puts(s, KRETPROBE_MSG); |
1604 | else | |
2e2ca155 SR |
1605 | ret = seq_print_ip_sym(s, |
1606 | field->fn.parent_ip, | |
76094a2c | 1607 | sym_flags); |
b3806b43 SR |
1608 | if (!ret) |
1609 | return 0; | |
bc0c38d1 | 1610 | } |
b3806b43 SR |
1611 | ret = trace_seq_printf(s, "\n"); |
1612 | if (!ret) | |
1613 | return 0; | |
bc0c38d1 SR |
1614 | break; |
1615 | case TRACE_CTX: | |
57422797 | 1616 | case TRACE_WAKE: |
2e2ca155 SR |
1617 | S = field->ctx.prev_state < sizeof(state_to_char) ? |
1618 | state_to_char[field->ctx.prev_state] : 'X'; | |
1619 | T = field->ctx.next_state < sizeof(state_to_char) ? | |
1620 | state_to_char[field->ctx.next_state] : 'X'; | |
bac524d3 | 1621 | ret = trace_seq_printf(s, " %5d:%3d:%c %s %5d:%3d:%c\n", |
2e2ca155 SR |
1622 | field->ctx.prev_pid, |
1623 | field->ctx.prev_prio, | |
b3806b43 | 1624 | S, |
57422797 | 1625 | entry->type == TRACE_CTX ? "==>" : " +", |
2e2ca155 SR |
1626 | field->ctx.next_pid, |
1627 | field->ctx.next_prio, | |
bac524d3 | 1628 | T); |
b3806b43 SR |
1629 | if (!ret) |
1630 | return 0; | |
bc0c38d1 | 1631 | break; |
f0a920d5 | 1632 | case TRACE_SPECIAL: |
88a4216c | 1633 | ret = trace_seq_printf(s, "# %ld %ld %ld\n", |
2e2ca155 SR |
1634 | field->special.arg1, |
1635 | field->special.arg2, | |
1636 | field->special.arg3); | |
f0a920d5 IM |
1637 | if (!ret) |
1638 | return 0; | |
1639 | break; | |
86387f7e IM |
1640 | case TRACE_STACK: |
1641 | for (i = 0; i < FTRACE_STACK_ENTRIES; i++) { | |
1642 | if (i) { | |
1643 | ret = trace_seq_puts(s, " <= "); | |
1644 | if (!ret) | |
1645 | return 0; | |
1646 | } | |
2e2ca155 | 1647 | ret = seq_print_ip_sym(s, field->stack.caller[i], |
86387f7e IM |
1648 | sym_flags); |
1649 | if (!ret) | |
1650 | return 0; | |
1651 | } | |
1652 | ret = trace_seq_puts(s, "\n"); | |
1653 | if (!ret) | |
1654 | return 0; | |
1655 | break; | |
bc0c38d1 | 1656 | } |
b3806b43 | 1657 | return 1; |
bc0c38d1 SR |
1658 | } |
1659 | ||
e309b41d | 1660 | static int print_raw_fmt(struct trace_iterator *iter) |
f9896bf3 IM |
1661 | { |
1662 | struct trace_seq *s = &iter->seq; | |
1663 | struct trace_entry *entry; | |
2e2ca155 | 1664 | struct trace_field *field; |
f9896bf3 | 1665 | int ret; |
bac524d3 | 1666 | int S, T; |
f9896bf3 IM |
1667 | |
1668 | entry = iter->ent; | |
2e2ca155 | 1669 | field = &entry->field; |
f9896bf3 IM |
1670 | |
1671 | ret = trace_seq_printf(s, "%d %d %llu ", | |
2e2ca155 | 1672 | field->pid, iter->cpu, field->t); |
f9896bf3 IM |
1673 | if (!ret) |
1674 | return 0; | |
1675 | ||
1676 | switch (entry->type) { | |
1677 | case TRACE_FN: | |
1678 | ret = trace_seq_printf(s, "%x %x\n", | |
2e2ca155 SR |
1679 | field->fn.ip, |
1680 | field->fn.parent_ip); | |
f9896bf3 IM |
1681 | if (!ret) |
1682 | return 0; | |
1683 | break; | |
1684 | case TRACE_CTX: | |
57422797 | 1685 | case TRACE_WAKE: |
2e2ca155 SR |
1686 | S = field->ctx.prev_state < sizeof(state_to_char) ? |
1687 | state_to_char[field->ctx.prev_state] : 'X'; | |
1688 | T = field->ctx.next_state < sizeof(state_to_char) ? | |
1689 | state_to_char[field->ctx.next_state] : 'X'; | |
57422797 IM |
1690 | if (entry->type == TRACE_WAKE) |
1691 | S = '+'; | |
bac524d3 | 1692 | ret = trace_seq_printf(s, "%d %d %c %d %d %c\n", |
2e2ca155 SR |
1693 | field->ctx.prev_pid, |
1694 | field->ctx.prev_prio, | |
f9896bf3 | 1695 | S, |
2e2ca155 SR |
1696 | field->ctx.next_pid, |
1697 | field->ctx.next_prio, | |
bac524d3 | 1698 | T); |
f9896bf3 IM |
1699 | if (!ret) |
1700 | return 0; | |
1701 | break; | |
f0a920d5 | 1702 | case TRACE_SPECIAL: |
86387f7e | 1703 | case TRACE_STACK: |
88a4216c | 1704 | ret = trace_seq_printf(s, "# %ld %ld %ld\n", |
2e2ca155 SR |
1705 | field->special.arg1, |
1706 | field->special.arg2, | |
1707 | field->special.arg3); | |
f0a920d5 IM |
1708 | if (!ret) |
1709 | return 0; | |
1710 | break; | |
f9896bf3 IM |
1711 | } |
1712 | return 1; | |
1713 | } | |
1714 | ||
cb0f12aa IM |
1715 | #define SEQ_PUT_FIELD_RET(s, x) \ |
1716 | do { \ | |
1717 | if (!trace_seq_putmem(s, &(x), sizeof(x))) \ | |
1718 | return 0; \ | |
1719 | } while (0) | |
1720 | ||
5e3ca0ec IM |
1721 | #define SEQ_PUT_HEX_FIELD_RET(s, x) \ |
1722 | do { \ | |
1723 | if (!trace_seq_putmem_hex(s, &(x), sizeof(x))) \ | |
1724 | return 0; \ | |
1725 | } while (0) | |
1726 | ||
e309b41d | 1727 | static int print_hex_fmt(struct trace_iterator *iter) |
5e3ca0ec IM |
1728 | { |
1729 | struct trace_seq *s = &iter->seq; | |
1730 | unsigned char newline = '\n'; | |
1731 | struct trace_entry *entry; | |
2e2ca155 | 1732 | struct trace_field *field; |
bac524d3 | 1733 | int S, T; |
5e3ca0ec IM |
1734 | |
1735 | entry = iter->ent; | |
2e2ca155 | 1736 | field = &entry->field; |
5e3ca0ec | 1737 | |
2e2ca155 | 1738 | SEQ_PUT_HEX_FIELD_RET(s, field->pid); |
5e3ca0ec | 1739 | SEQ_PUT_HEX_FIELD_RET(s, iter->cpu); |
2e2ca155 | 1740 | SEQ_PUT_HEX_FIELD_RET(s, field->t); |
5e3ca0ec IM |
1741 | |
1742 | switch (entry->type) { | |
1743 | case TRACE_FN: | |
2e2ca155 SR |
1744 | SEQ_PUT_HEX_FIELD_RET(s, field->fn.ip); |
1745 | SEQ_PUT_HEX_FIELD_RET(s, field->fn.parent_ip); | |
5e3ca0ec IM |
1746 | break; |
1747 | case TRACE_CTX: | |
57422797 | 1748 | case TRACE_WAKE: |
2e2ca155 SR |
1749 | S = field->ctx.prev_state < sizeof(state_to_char) ? |
1750 | state_to_char[field->ctx.prev_state] : 'X'; | |
1751 | T = field->ctx.next_state < sizeof(state_to_char) ? | |
1752 | state_to_char[field->ctx.next_state] : 'X'; | |
57422797 IM |
1753 | if (entry->type == TRACE_WAKE) |
1754 | S = '+'; | |
2e2ca155 SR |
1755 | SEQ_PUT_HEX_FIELD_RET(s, field->ctx.prev_pid); |
1756 | SEQ_PUT_HEX_FIELD_RET(s, field->ctx.prev_prio); | |
5e3ca0ec | 1757 | SEQ_PUT_HEX_FIELD_RET(s, S); |
2e2ca155 SR |
1758 | SEQ_PUT_HEX_FIELD_RET(s, field->ctx.next_pid); |
1759 | SEQ_PUT_HEX_FIELD_RET(s, field->ctx.next_prio); | |
bac524d3 | 1760 | SEQ_PUT_HEX_FIELD_RET(s, T); |
5e3ca0ec IM |
1761 | break; |
1762 | case TRACE_SPECIAL: | |
86387f7e | 1763 | case TRACE_STACK: |
2e2ca155 SR |
1764 | SEQ_PUT_HEX_FIELD_RET(s, field->special.arg1); |
1765 | SEQ_PUT_HEX_FIELD_RET(s, field->special.arg2); | |
1766 | SEQ_PUT_HEX_FIELD_RET(s, field->special.arg3); | |
5e3ca0ec IM |
1767 | break; |
1768 | } | |
1769 | SEQ_PUT_FIELD_RET(s, newline); | |
1770 | ||
1771 | return 1; | |
1772 | } | |
1773 | ||
e309b41d | 1774 | static int print_bin_fmt(struct trace_iterator *iter) |
cb0f12aa IM |
1775 | { |
1776 | struct trace_seq *s = &iter->seq; | |
1777 | struct trace_entry *entry; | |
2e2ca155 | 1778 | struct trace_field *field; |
cb0f12aa IM |
1779 | |
1780 | entry = iter->ent; | |
2e2ca155 | 1781 | field = &entry->field; |
cb0f12aa | 1782 | |
2e2ca155 SR |
1783 | SEQ_PUT_FIELD_RET(s, field->pid); |
1784 | SEQ_PUT_FIELD_RET(s, field->cpu); | |
1785 | SEQ_PUT_FIELD_RET(s, field->t); | |
cb0f12aa IM |
1786 | |
1787 | switch (entry->type) { | |
1788 | case TRACE_FN: | |
2e2ca155 SR |
1789 | SEQ_PUT_FIELD_RET(s, field->fn.ip); |
1790 | SEQ_PUT_FIELD_RET(s, field->fn.parent_ip); | |
cb0f12aa IM |
1791 | break; |
1792 | case TRACE_CTX: | |
2e2ca155 SR |
1793 | SEQ_PUT_FIELD_RET(s, field->ctx.prev_pid); |
1794 | SEQ_PUT_FIELD_RET(s, field->ctx.prev_prio); | |
1795 | SEQ_PUT_FIELD_RET(s, field->ctx.prev_state); | |
1796 | SEQ_PUT_FIELD_RET(s, field->ctx.next_pid); | |
1797 | SEQ_PUT_FIELD_RET(s, field->ctx.next_prio); | |
1798 | SEQ_PUT_FIELD_RET(s, field->ctx.next_state); | |
cb0f12aa | 1799 | break; |
f0a920d5 | 1800 | case TRACE_SPECIAL: |
86387f7e | 1801 | case TRACE_STACK: |
2e2ca155 SR |
1802 | SEQ_PUT_FIELD_RET(s, field->special.arg1); |
1803 | SEQ_PUT_FIELD_RET(s, field->special.arg2); | |
1804 | SEQ_PUT_FIELD_RET(s, field->special.arg3); | |
f0a920d5 | 1805 | break; |
cb0f12aa IM |
1806 | } |
1807 | return 1; | |
1808 | } | |
1809 | ||
bc0c38d1 SR |
1810 | static int trace_empty(struct trace_iterator *iter) |
1811 | { | |
1812 | struct trace_array_cpu *data; | |
1813 | int cpu; | |
1814 | ||
ab46428c | 1815 | for_each_tracing_cpu(cpu) { |
bc0c38d1 SR |
1816 | data = iter->tr->data[cpu]; |
1817 | ||
b3806b43 SR |
1818 | if (head_page(data) && data->trace_idx && |
1819 | (data->trace_tail != data->trace_head || | |
1820 | data->trace_tail_idx != data->trace_head_idx)) | |
bc0c38d1 SR |
1821 | return 0; |
1822 | } | |
1823 | return 1; | |
1824 | } | |
1825 | ||
f9896bf3 IM |
1826 | static int print_trace_line(struct trace_iterator *iter) |
1827 | { | |
72829bc3 TG |
1828 | if (iter->trace && iter->trace->print_line) |
1829 | return iter->trace->print_line(iter); | |
1830 | ||
cb0f12aa IM |
1831 | if (trace_flags & TRACE_ITER_BIN) |
1832 | return print_bin_fmt(iter); | |
1833 | ||
5e3ca0ec IM |
1834 | if (trace_flags & TRACE_ITER_HEX) |
1835 | return print_hex_fmt(iter); | |
1836 | ||
f9896bf3 IM |
1837 | if (trace_flags & TRACE_ITER_RAW) |
1838 | return print_raw_fmt(iter); | |
1839 | ||
1840 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) | |
1841 | return print_lat_fmt(iter, iter->idx, iter->cpu); | |
1842 | ||
1843 | return print_trace_fmt(iter); | |
1844 | } | |
1845 | ||
bc0c38d1 SR |
1846 | static int s_show(struct seq_file *m, void *v) |
1847 | { | |
1848 | struct trace_iterator *iter = v; | |
1849 | ||
1850 | if (iter->ent == NULL) { | |
1851 | if (iter->tr) { | |
1852 | seq_printf(m, "# tracer: %s\n", iter->trace->name); | |
1853 | seq_puts(m, "#\n"); | |
1854 | } | |
1855 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) { | |
1856 | /* print nothing if the buffers are empty */ | |
1857 | if (trace_empty(iter)) | |
1858 | return 0; | |
1859 | print_trace_header(m, iter); | |
1860 | if (!(trace_flags & TRACE_ITER_VERBOSE)) | |
1861 | print_lat_help_header(m); | |
1862 | } else { | |
1863 | if (!(trace_flags & TRACE_ITER_VERBOSE)) | |
1864 | print_func_help_header(m); | |
1865 | } | |
1866 | } else { | |
f9896bf3 | 1867 | print_trace_line(iter); |
214023c3 | 1868 | trace_print_seq(m, &iter->seq); |
bc0c38d1 SR |
1869 | } |
1870 | ||
1871 | return 0; | |
1872 | } | |
1873 | ||
1874 | static struct seq_operations tracer_seq_ops = { | |
4bf39a94 IM |
1875 | .start = s_start, |
1876 | .next = s_next, | |
1877 | .stop = s_stop, | |
1878 | .show = s_show, | |
bc0c38d1 SR |
1879 | }; |
1880 | ||
e309b41d | 1881 | static struct trace_iterator * |
bc0c38d1 SR |
1882 | __tracing_open(struct inode *inode, struct file *file, int *ret) |
1883 | { | |
1884 | struct trace_iterator *iter; | |
1885 | ||
60a11774 SR |
1886 | if (tracing_disabled) { |
1887 | *ret = -ENODEV; | |
1888 | return NULL; | |
1889 | } | |
1890 | ||
bc0c38d1 SR |
1891 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); |
1892 | if (!iter) { | |
1893 | *ret = -ENOMEM; | |
1894 | goto out; | |
1895 | } | |
1896 | ||
1897 | mutex_lock(&trace_types_lock); | |
1898 | if (current_trace && current_trace->print_max) | |
1899 | iter->tr = &max_tr; | |
1900 | else | |
1901 | iter->tr = inode->i_private; | |
1902 | iter->trace = current_trace; | |
1903 | iter->pos = -1; | |
1904 | ||
1905 | /* TODO stop tracer */ | |
1906 | *ret = seq_open(file, &tracer_seq_ops); | |
1907 | if (!*ret) { | |
1908 | struct seq_file *m = file->private_data; | |
1909 | m->private = iter; | |
1910 | ||
1911 | /* stop the trace while dumping */ | |
60bc0800 | 1912 | if (iter->tr->ctrl) { |
bc0c38d1 | 1913 | tracer_enabled = 0; |
60bc0800 SR |
1914 | ftrace_function_enabled = 0; |
1915 | } | |
bc0c38d1 SR |
1916 | |
1917 | if (iter->trace && iter->trace->open) | |
1918 | iter->trace->open(iter); | |
1919 | } else { | |
1920 | kfree(iter); | |
1921 | iter = NULL; | |
1922 | } | |
1923 | mutex_unlock(&trace_types_lock); | |
1924 | ||
1925 | out: | |
1926 | return iter; | |
1927 | } | |
1928 | ||
1929 | int tracing_open_generic(struct inode *inode, struct file *filp) | |
1930 | { | |
60a11774 SR |
1931 | if (tracing_disabled) |
1932 | return -ENODEV; | |
1933 | ||
bc0c38d1 SR |
1934 | filp->private_data = inode->i_private; |
1935 | return 0; | |
1936 | } | |
1937 | ||
1938 | int tracing_release(struct inode *inode, struct file *file) | |
1939 | { | |
1940 | struct seq_file *m = (struct seq_file *)file->private_data; | |
1941 | struct trace_iterator *iter = m->private; | |
1942 | ||
1943 | mutex_lock(&trace_types_lock); | |
1944 | if (iter->trace && iter->trace->close) | |
1945 | iter->trace->close(iter); | |
1946 | ||
1947 | /* reenable tracing if it was previously enabled */ | |
60bc0800 | 1948 | if (iter->tr->ctrl) { |
bc0c38d1 | 1949 | tracer_enabled = 1; |
60bc0800 SR |
1950 | /* |
1951 | * It is safe to enable function tracing even if it | |
1952 | * isn't used | |
1953 | */ | |
1954 | ftrace_function_enabled = 1; | |
1955 | } | |
bc0c38d1 SR |
1956 | mutex_unlock(&trace_types_lock); |
1957 | ||
1958 | seq_release(inode, file); | |
1959 | kfree(iter); | |
1960 | return 0; | |
1961 | } | |
1962 | ||
1963 | static int tracing_open(struct inode *inode, struct file *file) | |
1964 | { | |
1965 | int ret; | |
1966 | ||
1967 | __tracing_open(inode, file, &ret); | |
1968 | ||
1969 | return ret; | |
1970 | } | |
1971 | ||
1972 | static int tracing_lt_open(struct inode *inode, struct file *file) | |
1973 | { | |
1974 | struct trace_iterator *iter; | |
1975 | int ret; | |
1976 | ||
1977 | iter = __tracing_open(inode, file, &ret); | |
1978 | ||
1979 | if (!ret) | |
1980 | iter->iter_flags |= TRACE_FILE_LAT_FMT; | |
1981 | ||
1982 | return ret; | |
1983 | } | |
1984 | ||
1985 | ||
e309b41d | 1986 | static void * |
bc0c38d1 SR |
1987 | t_next(struct seq_file *m, void *v, loff_t *pos) |
1988 | { | |
1989 | struct tracer *t = m->private; | |
1990 | ||
1991 | (*pos)++; | |
1992 | ||
1993 | if (t) | |
1994 | t = t->next; | |
1995 | ||
1996 | m->private = t; | |
1997 | ||
1998 | return t; | |
1999 | } | |
2000 | ||
2001 | static void *t_start(struct seq_file *m, loff_t *pos) | |
2002 | { | |
2003 | struct tracer *t = m->private; | |
2004 | loff_t l = 0; | |
2005 | ||
2006 | mutex_lock(&trace_types_lock); | |
2007 | for (; t && l < *pos; t = t_next(m, t, &l)) | |
2008 | ; | |
2009 | ||
2010 | return t; | |
2011 | } | |
2012 | ||
2013 | static void t_stop(struct seq_file *m, void *p) | |
2014 | { | |
2015 | mutex_unlock(&trace_types_lock); | |
2016 | } | |
2017 | ||
2018 | static int t_show(struct seq_file *m, void *v) | |
2019 | { | |
2020 | struct tracer *t = v; | |
2021 | ||
2022 | if (!t) | |
2023 | return 0; | |
2024 | ||
2025 | seq_printf(m, "%s", t->name); | |
2026 | if (t->next) | |
2027 | seq_putc(m, ' '); | |
2028 | else | |
2029 | seq_putc(m, '\n'); | |
2030 | ||
2031 | return 0; | |
2032 | } | |
2033 | ||
2034 | static struct seq_operations show_traces_seq_ops = { | |
4bf39a94 IM |
2035 | .start = t_start, |
2036 | .next = t_next, | |
2037 | .stop = t_stop, | |
2038 | .show = t_show, | |
bc0c38d1 SR |
2039 | }; |
2040 | ||
2041 | static int show_traces_open(struct inode *inode, struct file *file) | |
2042 | { | |
2043 | int ret; | |
2044 | ||
60a11774 SR |
2045 | if (tracing_disabled) |
2046 | return -ENODEV; | |
2047 | ||
bc0c38d1 SR |
2048 | ret = seq_open(file, &show_traces_seq_ops); |
2049 | if (!ret) { | |
2050 | struct seq_file *m = file->private_data; | |
2051 | m->private = trace_types; | |
2052 | } | |
2053 | ||
2054 | return ret; | |
2055 | } | |
2056 | ||
2057 | static struct file_operations tracing_fops = { | |
4bf39a94 IM |
2058 | .open = tracing_open, |
2059 | .read = seq_read, | |
2060 | .llseek = seq_lseek, | |
2061 | .release = tracing_release, | |
bc0c38d1 SR |
2062 | }; |
2063 | ||
2064 | static struct file_operations tracing_lt_fops = { | |
4bf39a94 IM |
2065 | .open = tracing_lt_open, |
2066 | .read = seq_read, | |
2067 | .llseek = seq_lseek, | |
2068 | .release = tracing_release, | |
bc0c38d1 SR |
2069 | }; |
2070 | ||
2071 | static struct file_operations show_traces_fops = { | |
c7078de1 IM |
2072 | .open = show_traces_open, |
2073 | .read = seq_read, | |
2074 | .release = seq_release, | |
2075 | }; | |
2076 | ||
36dfe925 IM |
2077 | /* |
2078 | * Only trace on a CPU if the bitmask is set: | |
2079 | */ | |
2080 | static cpumask_t tracing_cpumask = CPU_MASK_ALL; | |
2081 | ||
2082 | /* | |
2083 | * When tracing/tracing_cpu_mask is modified then this holds | |
2084 | * the new bitmask we are about to install: | |
2085 | */ | |
2086 | static cpumask_t tracing_cpumask_new; | |
2087 | ||
2088 | /* | |
2089 | * The tracer itself will not take this lock, but still we want | |
2090 | * to provide a consistent cpumask to user-space: | |
2091 | */ | |
2092 | static DEFINE_MUTEX(tracing_cpumask_update_lock); | |
2093 | ||
2094 | /* | |
2095 | * Temporary storage for the character representation of the | |
2096 | * CPU bitmask (and one more byte for the newline): | |
2097 | */ | |
2098 | static char mask_str[NR_CPUS + 1]; | |
2099 | ||
c7078de1 IM |
2100 | static ssize_t |
2101 | tracing_cpumask_read(struct file *filp, char __user *ubuf, | |
2102 | size_t count, loff_t *ppos) | |
2103 | { | |
36dfe925 | 2104 | int len; |
c7078de1 IM |
2105 | |
2106 | mutex_lock(&tracing_cpumask_update_lock); | |
36dfe925 IM |
2107 | |
2108 | len = cpumask_scnprintf(mask_str, count, tracing_cpumask); | |
2109 | if (count - len < 2) { | |
2110 | count = -EINVAL; | |
2111 | goto out_err; | |
2112 | } | |
2113 | len += sprintf(mask_str + len, "\n"); | |
2114 | count = simple_read_from_buffer(ubuf, count, ppos, mask_str, NR_CPUS+1); | |
2115 | ||
2116 | out_err: | |
c7078de1 IM |
2117 | mutex_unlock(&tracing_cpumask_update_lock); |
2118 | ||
2119 | return count; | |
2120 | } | |
2121 | ||
2122 | static ssize_t | |
2123 | tracing_cpumask_write(struct file *filp, const char __user *ubuf, | |
2124 | size_t count, loff_t *ppos) | |
2125 | { | |
36dfe925 | 2126 | int err, cpu; |
c7078de1 IM |
2127 | |
2128 | mutex_lock(&tracing_cpumask_update_lock); | |
36dfe925 | 2129 | err = cpumask_parse_user(ubuf, count, tracing_cpumask_new); |
c7078de1 | 2130 | if (err) |
36dfe925 IM |
2131 | goto err_unlock; |
2132 | ||
92205c23 SR |
2133 | raw_local_irq_disable(); |
2134 | __raw_spin_lock(&ftrace_max_lock); | |
ab46428c | 2135 | for_each_tracing_cpu(cpu) { |
36dfe925 IM |
2136 | /* |
2137 | * Increase/decrease the disabled counter if we are | |
2138 | * about to flip a bit in the cpumask: | |
2139 | */ | |
2140 | if (cpu_isset(cpu, tracing_cpumask) && | |
2141 | !cpu_isset(cpu, tracing_cpumask_new)) { | |
2142 | atomic_inc(&global_trace.data[cpu]->disabled); | |
2143 | } | |
2144 | if (!cpu_isset(cpu, tracing_cpumask) && | |
2145 | cpu_isset(cpu, tracing_cpumask_new)) { | |
2146 | atomic_dec(&global_trace.data[cpu]->disabled); | |
2147 | } | |
2148 | } | |
92205c23 SR |
2149 | __raw_spin_unlock(&ftrace_max_lock); |
2150 | raw_local_irq_enable(); | |
36dfe925 IM |
2151 | |
2152 | tracing_cpumask = tracing_cpumask_new; | |
2153 | ||
2154 | mutex_unlock(&tracing_cpumask_update_lock); | |
c7078de1 IM |
2155 | |
2156 | return count; | |
36dfe925 IM |
2157 | |
2158 | err_unlock: | |
2159 | mutex_unlock(&tracing_cpumask_update_lock); | |
2160 | ||
2161 | return err; | |
c7078de1 IM |
2162 | } |
2163 | ||
2164 | static struct file_operations tracing_cpumask_fops = { | |
2165 | .open = tracing_open_generic, | |
2166 | .read = tracing_cpumask_read, | |
2167 | .write = tracing_cpumask_write, | |
bc0c38d1 SR |
2168 | }; |
2169 | ||
2170 | static ssize_t | |
2171 | tracing_iter_ctrl_read(struct file *filp, char __user *ubuf, | |
2172 | size_t cnt, loff_t *ppos) | |
2173 | { | |
2174 | char *buf; | |
2175 | int r = 0; | |
2176 | int len = 0; | |
2177 | int i; | |
2178 | ||
2179 | /* calulate max size */ | |
2180 | for (i = 0; trace_options[i]; i++) { | |
2181 | len += strlen(trace_options[i]); | |
2182 | len += 3; /* "no" and space */ | |
2183 | } | |
2184 | ||
2185 | /* +2 for \n and \0 */ | |
2186 | buf = kmalloc(len + 2, GFP_KERNEL); | |
2187 | if (!buf) | |
2188 | return -ENOMEM; | |
2189 | ||
2190 | for (i = 0; trace_options[i]; i++) { | |
2191 | if (trace_flags & (1 << i)) | |
2192 | r += sprintf(buf + r, "%s ", trace_options[i]); | |
2193 | else | |
2194 | r += sprintf(buf + r, "no%s ", trace_options[i]); | |
2195 | } | |
2196 | ||
2197 | r += sprintf(buf + r, "\n"); | |
2198 | WARN_ON(r >= len + 2); | |
2199 | ||
36dfe925 | 2200 | r = simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
2201 | |
2202 | kfree(buf); | |
2203 | ||
2204 | return r; | |
2205 | } | |
2206 | ||
2207 | static ssize_t | |
2208 | tracing_iter_ctrl_write(struct file *filp, const char __user *ubuf, | |
2209 | size_t cnt, loff_t *ppos) | |
2210 | { | |
2211 | char buf[64]; | |
2212 | char *cmp = buf; | |
2213 | int neg = 0; | |
2214 | int i; | |
2215 | ||
cffae437 SR |
2216 | if (cnt >= sizeof(buf)) |
2217 | return -EINVAL; | |
bc0c38d1 SR |
2218 | |
2219 | if (copy_from_user(&buf, ubuf, cnt)) | |
2220 | return -EFAULT; | |
2221 | ||
2222 | buf[cnt] = 0; | |
2223 | ||
2224 | if (strncmp(buf, "no", 2) == 0) { | |
2225 | neg = 1; | |
2226 | cmp += 2; | |
2227 | } | |
2228 | ||
2229 | for (i = 0; trace_options[i]; i++) { | |
2230 | int len = strlen(trace_options[i]); | |
2231 | ||
2232 | if (strncmp(cmp, trace_options[i], len) == 0) { | |
2233 | if (neg) | |
2234 | trace_flags &= ~(1 << i); | |
2235 | else | |
2236 | trace_flags |= (1 << i); | |
2237 | break; | |
2238 | } | |
2239 | } | |
442e544c IM |
2240 | /* |
2241 | * If no option could be set, return an error: | |
2242 | */ | |
2243 | if (!trace_options[i]) | |
2244 | return -EINVAL; | |
bc0c38d1 SR |
2245 | |
2246 | filp->f_pos += cnt; | |
2247 | ||
2248 | return cnt; | |
2249 | } | |
2250 | ||
2251 | static struct file_operations tracing_iter_fops = { | |
c7078de1 IM |
2252 | .open = tracing_open_generic, |
2253 | .read = tracing_iter_ctrl_read, | |
2254 | .write = tracing_iter_ctrl_write, | |
bc0c38d1 SR |
2255 | }; |
2256 | ||
7bd2f24c IM |
2257 | static const char readme_msg[] = |
2258 | "tracing mini-HOWTO:\n\n" | |
2259 | "# mkdir /debug\n" | |
2260 | "# mount -t debugfs nodev /debug\n\n" | |
2261 | "# cat /debug/tracing/available_tracers\n" | |
2262 | "wakeup preemptirqsoff preemptoff irqsoff ftrace sched_switch none\n\n" | |
2263 | "# cat /debug/tracing/current_tracer\n" | |
2264 | "none\n" | |
2265 | "# echo sched_switch > /debug/tracing/current_tracer\n" | |
2266 | "# cat /debug/tracing/current_tracer\n" | |
2267 | "sched_switch\n" | |
2268 | "# cat /debug/tracing/iter_ctrl\n" | |
2269 | "noprint-parent nosym-offset nosym-addr noverbose\n" | |
2270 | "# echo print-parent > /debug/tracing/iter_ctrl\n" | |
2271 | "# echo 1 > /debug/tracing/tracing_enabled\n" | |
2272 | "# cat /debug/tracing/trace > /tmp/trace.txt\n" | |
2273 | "echo 0 > /debug/tracing/tracing_enabled\n" | |
2274 | ; | |
2275 | ||
2276 | static ssize_t | |
2277 | tracing_readme_read(struct file *filp, char __user *ubuf, | |
2278 | size_t cnt, loff_t *ppos) | |
2279 | { | |
2280 | return simple_read_from_buffer(ubuf, cnt, ppos, | |
2281 | readme_msg, strlen(readme_msg)); | |
2282 | } | |
2283 | ||
2284 | static struct file_operations tracing_readme_fops = { | |
c7078de1 IM |
2285 | .open = tracing_open_generic, |
2286 | .read = tracing_readme_read, | |
7bd2f24c IM |
2287 | }; |
2288 | ||
bc0c38d1 SR |
2289 | static ssize_t |
2290 | tracing_ctrl_read(struct file *filp, char __user *ubuf, | |
2291 | size_t cnt, loff_t *ppos) | |
2292 | { | |
2293 | struct trace_array *tr = filp->private_data; | |
2294 | char buf[64]; | |
2295 | int r; | |
2296 | ||
2297 | r = sprintf(buf, "%ld\n", tr->ctrl); | |
4e3c3333 | 2298 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
2299 | } |
2300 | ||
2301 | static ssize_t | |
2302 | tracing_ctrl_write(struct file *filp, const char __user *ubuf, | |
2303 | size_t cnt, loff_t *ppos) | |
2304 | { | |
2305 | struct trace_array *tr = filp->private_data; | |
bc0c38d1 | 2306 | char buf[64]; |
c6caeeb1 SR |
2307 | long val; |
2308 | int ret; | |
bc0c38d1 | 2309 | |
cffae437 SR |
2310 | if (cnt >= sizeof(buf)) |
2311 | return -EINVAL; | |
bc0c38d1 SR |
2312 | |
2313 | if (copy_from_user(&buf, ubuf, cnt)) | |
2314 | return -EFAULT; | |
2315 | ||
2316 | buf[cnt] = 0; | |
2317 | ||
c6caeeb1 SR |
2318 | ret = strict_strtoul(buf, 10, &val); |
2319 | if (ret < 0) | |
2320 | return ret; | |
bc0c38d1 SR |
2321 | |
2322 | val = !!val; | |
2323 | ||
2324 | mutex_lock(&trace_types_lock); | |
2325 | if (tr->ctrl ^ val) { | |
2326 | if (val) | |
2327 | tracer_enabled = 1; | |
2328 | else | |
2329 | tracer_enabled = 0; | |
2330 | ||
2331 | tr->ctrl = val; | |
2332 | ||
2333 | if (current_trace && current_trace->ctrl_update) | |
2334 | current_trace->ctrl_update(tr); | |
2335 | } | |
2336 | mutex_unlock(&trace_types_lock); | |
2337 | ||
2338 | filp->f_pos += cnt; | |
2339 | ||
2340 | return cnt; | |
2341 | } | |
2342 | ||
2343 | static ssize_t | |
2344 | tracing_set_trace_read(struct file *filp, char __user *ubuf, | |
2345 | size_t cnt, loff_t *ppos) | |
2346 | { | |
2347 | char buf[max_tracer_type_len+2]; | |
2348 | int r; | |
2349 | ||
2350 | mutex_lock(&trace_types_lock); | |
2351 | if (current_trace) | |
2352 | r = sprintf(buf, "%s\n", current_trace->name); | |
2353 | else | |
2354 | r = sprintf(buf, "\n"); | |
2355 | mutex_unlock(&trace_types_lock); | |
2356 | ||
4bf39a94 | 2357 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
2358 | } |
2359 | ||
2360 | static ssize_t | |
2361 | tracing_set_trace_write(struct file *filp, const char __user *ubuf, | |
2362 | size_t cnt, loff_t *ppos) | |
2363 | { | |
2364 | struct trace_array *tr = &global_trace; | |
2365 | struct tracer *t; | |
2366 | char buf[max_tracer_type_len+1]; | |
2367 | int i; | |
2368 | ||
2369 | if (cnt > max_tracer_type_len) | |
2370 | cnt = max_tracer_type_len; | |
2371 | ||
2372 | if (copy_from_user(&buf, ubuf, cnt)) | |
2373 | return -EFAULT; | |
2374 | ||
2375 | buf[cnt] = 0; | |
2376 | ||
2377 | /* strip ending whitespace. */ | |
2378 | for (i = cnt - 1; i > 0 && isspace(buf[i]); i--) | |
2379 | buf[i] = 0; | |
2380 | ||
2381 | mutex_lock(&trace_types_lock); | |
2382 | for (t = trace_types; t; t = t->next) { | |
2383 | if (strcmp(t->name, buf) == 0) | |
2384 | break; | |
2385 | } | |
2386 | if (!t || t == current_trace) | |
2387 | goto out; | |
2388 | ||
2389 | if (current_trace && current_trace->reset) | |
2390 | current_trace->reset(tr); | |
2391 | ||
2392 | current_trace = t; | |
2393 | if (t->init) | |
2394 | t->init(tr); | |
2395 | ||
2396 | out: | |
2397 | mutex_unlock(&trace_types_lock); | |
2398 | ||
2399 | filp->f_pos += cnt; | |
2400 | ||
2401 | return cnt; | |
2402 | } | |
2403 | ||
2404 | static ssize_t | |
2405 | tracing_max_lat_read(struct file *filp, char __user *ubuf, | |
2406 | size_t cnt, loff_t *ppos) | |
2407 | { | |
2408 | unsigned long *ptr = filp->private_data; | |
2409 | char buf[64]; | |
2410 | int r; | |
2411 | ||
cffae437 | 2412 | r = snprintf(buf, sizeof(buf), "%ld\n", |
bc0c38d1 | 2413 | *ptr == (unsigned long)-1 ? -1 : nsecs_to_usecs(*ptr)); |
cffae437 SR |
2414 | if (r > sizeof(buf)) |
2415 | r = sizeof(buf); | |
4bf39a94 | 2416 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
2417 | } |
2418 | ||
2419 | static ssize_t | |
2420 | tracing_max_lat_write(struct file *filp, const char __user *ubuf, | |
2421 | size_t cnt, loff_t *ppos) | |
2422 | { | |
2423 | long *ptr = filp->private_data; | |
bc0c38d1 | 2424 | char buf[64]; |
c6caeeb1 SR |
2425 | long val; |
2426 | int ret; | |
bc0c38d1 | 2427 | |
cffae437 SR |
2428 | if (cnt >= sizeof(buf)) |
2429 | return -EINVAL; | |
bc0c38d1 SR |
2430 | |
2431 | if (copy_from_user(&buf, ubuf, cnt)) | |
2432 | return -EFAULT; | |
2433 | ||
2434 | buf[cnt] = 0; | |
2435 | ||
c6caeeb1 SR |
2436 | ret = strict_strtoul(buf, 10, &val); |
2437 | if (ret < 0) | |
2438 | return ret; | |
bc0c38d1 SR |
2439 | |
2440 | *ptr = val * 1000; | |
2441 | ||
2442 | return cnt; | |
2443 | } | |
2444 | ||
b3806b43 SR |
2445 | static atomic_t tracing_reader; |
2446 | ||
2447 | static int tracing_open_pipe(struct inode *inode, struct file *filp) | |
2448 | { | |
2449 | struct trace_iterator *iter; | |
2450 | ||
2451 | if (tracing_disabled) | |
2452 | return -ENODEV; | |
2453 | ||
2454 | /* We only allow for reader of the pipe */ | |
2455 | if (atomic_inc_return(&tracing_reader) != 1) { | |
2456 | atomic_dec(&tracing_reader); | |
2457 | return -EBUSY; | |
2458 | } | |
2459 | ||
2460 | /* create a buffer to store the information to pass to userspace */ | |
2461 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); | |
2462 | if (!iter) | |
2463 | return -ENOMEM; | |
2464 | ||
107bad8b | 2465 | mutex_lock(&trace_types_lock); |
b3806b43 | 2466 | iter->tr = &global_trace; |
72829bc3 | 2467 | iter->trace = current_trace; |
b3806b43 SR |
2468 | filp->private_data = iter; |
2469 | ||
107bad8b SR |
2470 | if (iter->trace->pipe_open) |
2471 | iter->trace->pipe_open(iter); | |
2472 | mutex_unlock(&trace_types_lock); | |
2473 | ||
b3806b43 SR |
2474 | return 0; |
2475 | } | |
2476 | ||
2477 | static int tracing_release_pipe(struct inode *inode, struct file *file) | |
2478 | { | |
2479 | struct trace_iterator *iter = file->private_data; | |
2480 | ||
2481 | kfree(iter); | |
2482 | atomic_dec(&tracing_reader); | |
2483 | ||
2484 | return 0; | |
2485 | } | |
2486 | ||
2a2cc8f7 SSP |
2487 | static unsigned int |
2488 | tracing_poll_pipe(struct file *filp, poll_table *poll_table) | |
2489 | { | |
2490 | struct trace_iterator *iter = filp->private_data; | |
2491 | ||
2492 | if (trace_flags & TRACE_ITER_BLOCK) { | |
2493 | /* | |
2494 | * Always select as readable when in blocking mode | |
2495 | */ | |
2496 | return POLLIN | POLLRDNORM; | |
afc2abc0 | 2497 | } else { |
2a2cc8f7 SSP |
2498 | if (!trace_empty(iter)) |
2499 | return POLLIN | POLLRDNORM; | |
2500 | poll_wait(filp, &trace_wait, poll_table); | |
2501 | if (!trace_empty(iter)) | |
2502 | return POLLIN | POLLRDNORM; | |
2503 | ||
2504 | return 0; | |
2505 | } | |
2506 | } | |
2507 | ||
b3806b43 SR |
2508 | /* |
2509 | * Consumer reader. | |
2510 | */ | |
2511 | static ssize_t | |
2512 | tracing_read_pipe(struct file *filp, char __user *ubuf, | |
2513 | size_t cnt, loff_t *ppos) | |
2514 | { | |
2515 | struct trace_iterator *iter = filp->private_data; | |
2516 | struct trace_array_cpu *data; | |
2517 | static cpumask_t mask; | |
b3806b43 | 2518 | unsigned long flags; |
25770467 | 2519 | #ifdef CONFIG_FTRACE |
2e0f5761 | 2520 | int ftrace_save; |
25770467 | 2521 | #endif |
b3806b43 | 2522 | int cpu; |
6c6c2796 | 2523 | ssize_t sret; |
b3806b43 SR |
2524 | |
2525 | /* return any leftover data */ | |
6c6c2796 PP |
2526 | sret = trace_seq_to_user(&iter->seq, ubuf, cnt); |
2527 | if (sret != -EBUSY) | |
2528 | return sret; | |
2529 | sret = 0; | |
b3806b43 | 2530 | |
6c6c2796 | 2531 | trace_seq_reset(&iter->seq); |
b3806b43 | 2532 | |
107bad8b SR |
2533 | mutex_lock(&trace_types_lock); |
2534 | if (iter->trace->read) { | |
6c6c2796 PP |
2535 | sret = iter->trace->read(iter, filp, ubuf, cnt, ppos); |
2536 | if (sret) | |
107bad8b | 2537 | goto out; |
107bad8b SR |
2538 | } |
2539 | ||
b3806b43 | 2540 | while (trace_empty(iter)) { |
2dc8f095 | 2541 | |
107bad8b | 2542 | if ((filp->f_flags & O_NONBLOCK)) { |
6c6c2796 | 2543 | sret = -EAGAIN; |
107bad8b SR |
2544 | goto out; |
2545 | } | |
2dc8f095 | 2546 | |
b3806b43 SR |
2547 | /* |
2548 | * This is a make-shift waitqueue. The reason we don't use | |
2549 | * an actual wait queue is because: | |
2550 | * 1) we only ever have one waiter | |
2551 | * 2) the tracing, traces all functions, we don't want | |
2552 | * the overhead of calling wake_up and friends | |
2553 | * (and tracing them too) | |
2554 | * Anyway, this is really very primitive wakeup. | |
2555 | */ | |
2556 | set_current_state(TASK_INTERRUPTIBLE); | |
2557 | iter->tr->waiter = current; | |
2558 | ||
107bad8b SR |
2559 | mutex_unlock(&trace_types_lock); |
2560 | ||
9fe068e9 IM |
2561 | /* sleep for 100 msecs, and try again. */ |
2562 | schedule_timeout(HZ/10); | |
b3806b43 | 2563 | |
107bad8b SR |
2564 | mutex_lock(&trace_types_lock); |
2565 | ||
b3806b43 SR |
2566 | iter->tr->waiter = NULL; |
2567 | ||
107bad8b | 2568 | if (signal_pending(current)) { |
6c6c2796 | 2569 | sret = -EINTR; |
107bad8b SR |
2570 | goto out; |
2571 | } | |
b3806b43 | 2572 | |
84527997 | 2573 | if (iter->trace != current_trace) |
107bad8b | 2574 | goto out; |
84527997 | 2575 | |
b3806b43 SR |
2576 | /* |
2577 | * We block until we read something and tracing is disabled. | |
2578 | * We still block if tracing is disabled, but we have never | |
2579 | * read anything. This allows a user to cat this file, and | |
2580 | * then enable tracing. But after we have read something, | |
2581 | * we give an EOF when tracing is again disabled. | |
2582 | * | |
2583 | * iter->pos will be 0 if we haven't read anything. | |
2584 | */ | |
2585 | if (!tracer_enabled && iter->pos) | |
2586 | break; | |
2587 | ||
2588 | continue; | |
2589 | } | |
2590 | ||
2591 | /* stop when tracing is finished */ | |
2592 | if (trace_empty(iter)) | |
107bad8b | 2593 | goto out; |
b3806b43 SR |
2594 | |
2595 | if (cnt >= PAGE_SIZE) | |
2596 | cnt = PAGE_SIZE - 1; | |
2597 | ||
53d0aa77 | 2598 | /* reset all but tr, trace, and overruns */ |
53d0aa77 SR |
2599 | memset(&iter->seq, 0, |
2600 | sizeof(struct trace_iterator) - | |
2601 | offsetof(struct trace_iterator, seq)); | |
4823ed7e | 2602 | iter->pos = -1; |
b3806b43 SR |
2603 | |
2604 | /* | |
2605 | * We need to stop all tracing on all CPUS to read the | |
2606 | * the next buffer. This is a bit expensive, but is | |
2607 | * not done often. We fill all what we can read, | |
2608 | * and then release the locks again. | |
2609 | */ | |
2610 | ||
2611 | cpus_clear(mask); | |
2612 | local_irq_save(flags); | |
25770467 | 2613 | #ifdef CONFIG_FTRACE |
2e0f5761 IM |
2614 | ftrace_save = ftrace_enabled; |
2615 | ftrace_enabled = 0; | |
25770467 | 2616 | #endif |
2e0f5761 | 2617 | smp_wmb(); |
ab46428c | 2618 | for_each_tracing_cpu(cpu) { |
b3806b43 SR |
2619 | data = iter->tr->data[cpu]; |
2620 | ||
2621 | if (!head_page(data) || !data->trace_idx) | |
2622 | continue; | |
2623 | ||
2624 | atomic_inc(&data->disabled); | |
b3806b43 SR |
2625 | cpu_set(cpu, mask); |
2626 | } | |
2627 | ||
2e0f5761 IM |
2628 | for_each_cpu_mask(cpu, mask) { |
2629 | data = iter->tr->data[cpu]; | |
92205c23 | 2630 | __raw_spin_lock(&data->lock); |
53d0aa77 SR |
2631 | |
2632 | if (data->overrun > iter->last_overrun[cpu]) | |
2633 | iter->overrun[cpu] += | |
2634 | data->overrun - iter->last_overrun[cpu]; | |
2635 | iter->last_overrun[cpu] = data->overrun; | |
2e0f5761 IM |
2636 | } |
2637 | ||
088b1e42 | 2638 | while (find_next_entry_inc(iter) != NULL) { |
6c6c2796 | 2639 | int ret; |
088b1e42 SR |
2640 | int len = iter->seq.len; |
2641 | ||
f9896bf3 | 2642 | ret = print_trace_line(iter); |
088b1e42 SR |
2643 | if (!ret) { |
2644 | /* don't print partial lines */ | |
2645 | iter->seq.len = len; | |
b3806b43 | 2646 | break; |
088b1e42 | 2647 | } |
b3806b43 SR |
2648 | |
2649 | trace_consume(iter); | |
2650 | ||
2651 | if (iter->seq.len >= cnt) | |
2652 | break; | |
b3806b43 SR |
2653 | } |
2654 | ||
d4c5a2f5 | 2655 | for_each_cpu_mask(cpu, mask) { |
b3806b43 | 2656 | data = iter->tr->data[cpu]; |
92205c23 | 2657 | __raw_spin_unlock(&data->lock); |
2e0f5761 IM |
2658 | } |
2659 | ||
2660 | for_each_cpu_mask(cpu, mask) { | |
2661 | data = iter->tr->data[cpu]; | |
b3806b43 SR |
2662 | atomic_dec(&data->disabled); |
2663 | } | |
25770467 | 2664 | #ifdef CONFIG_FTRACE |
2e0f5761 | 2665 | ftrace_enabled = ftrace_save; |
25770467 | 2666 | #endif |
b3806b43 SR |
2667 | local_irq_restore(flags); |
2668 | ||
2669 | /* Now copy what we have to the user */ | |
6c6c2796 PP |
2670 | sret = trace_seq_to_user(&iter->seq, ubuf, cnt); |
2671 | if (iter->seq.readpos >= iter->seq.len) | |
b3806b43 | 2672 | trace_seq_reset(&iter->seq); |
6c6c2796 PP |
2673 | if (sret == -EBUSY) |
2674 | sret = 0; | |
b3806b43 | 2675 | |
107bad8b SR |
2676 | out: |
2677 | mutex_unlock(&trace_types_lock); | |
2678 | ||
6c6c2796 | 2679 | return sret; |
b3806b43 SR |
2680 | } |
2681 | ||
a98a3c3f SR |
2682 | static ssize_t |
2683 | tracing_entries_read(struct file *filp, char __user *ubuf, | |
2684 | size_t cnt, loff_t *ppos) | |
2685 | { | |
2686 | struct trace_array *tr = filp->private_data; | |
2687 | char buf[64]; | |
2688 | int r; | |
2689 | ||
2690 | r = sprintf(buf, "%lu\n", tr->entries); | |
2691 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
2692 | } | |
2693 | ||
2694 | static ssize_t | |
2695 | tracing_entries_write(struct file *filp, const char __user *ubuf, | |
2696 | size_t cnt, loff_t *ppos) | |
2697 | { | |
2698 | unsigned long val; | |
2699 | char buf[64]; | |
19384c03 | 2700 | int i, ret; |
a98a3c3f | 2701 | |
cffae437 SR |
2702 | if (cnt >= sizeof(buf)) |
2703 | return -EINVAL; | |
a98a3c3f SR |
2704 | |
2705 | if (copy_from_user(&buf, ubuf, cnt)) | |
2706 | return -EFAULT; | |
2707 | ||
2708 | buf[cnt] = 0; | |
2709 | ||
c6caeeb1 SR |
2710 | ret = strict_strtoul(buf, 10, &val); |
2711 | if (ret < 0) | |
2712 | return ret; | |
a98a3c3f SR |
2713 | |
2714 | /* must have at least 1 entry */ | |
2715 | if (!val) | |
2716 | return -EINVAL; | |
2717 | ||
2718 | mutex_lock(&trace_types_lock); | |
2719 | ||
2720 | if (current_trace != &no_tracer) { | |
2721 | cnt = -EBUSY; | |
2722 | pr_info("ftrace: set current_tracer to none" | |
2723 | " before modifying buffer size\n"); | |
2724 | goto out; | |
2725 | } | |
2726 | ||
2727 | if (val > global_trace.entries) { | |
3eefae99 SR |
2728 | long pages_requested; |
2729 | unsigned long freeable_pages; | |
2730 | ||
2731 | /* make sure we have enough memory before mapping */ | |
2732 | pages_requested = | |
2733 | (val + (ENTRIES_PER_PAGE-1)) / ENTRIES_PER_PAGE; | |
2734 | ||
2735 | /* account for each buffer (and max_tr) */ | |
2736 | pages_requested *= tracing_nr_buffers * 2; | |
2737 | ||
2738 | /* Check for overflow */ | |
2739 | if (pages_requested < 0) { | |
2740 | cnt = -ENOMEM; | |
2741 | goto out; | |
2742 | } | |
2743 | ||
2744 | freeable_pages = determine_dirtyable_memory(); | |
2745 | ||
2746 | /* we only allow to request 1/4 of useable memory */ | |
2747 | if (pages_requested > | |
2748 | ((freeable_pages + tracing_pages_allocated) / 4)) { | |
2749 | cnt = -ENOMEM; | |
2750 | goto out; | |
2751 | } | |
2752 | ||
a98a3c3f SR |
2753 | while (global_trace.entries < val) { |
2754 | if (trace_alloc_page()) { | |
2755 | cnt = -ENOMEM; | |
2756 | goto out; | |
2757 | } | |
3eefae99 SR |
2758 | /* double check that we don't go over the known pages */ |
2759 | if (tracing_pages_allocated > pages_requested) | |
2760 | break; | |
a98a3c3f | 2761 | } |
3eefae99 | 2762 | |
a98a3c3f SR |
2763 | } else { |
2764 | /* include the number of entries in val (inc of page entries) */ | |
2765 | while (global_trace.entries > val + (ENTRIES_PER_PAGE - 1)) | |
2766 | trace_free_page(); | |
2767 | } | |
2768 | ||
19384c03 SR |
2769 | /* check integrity */ |
2770 | for_each_tracing_cpu(i) | |
2771 | check_pages(global_trace.data[i]); | |
2772 | ||
a98a3c3f SR |
2773 | filp->f_pos += cnt; |
2774 | ||
19384c03 SR |
2775 | /* If check pages failed, return ENOMEM */ |
2776 | if (tracing_disabled) | |
2777 | cnt = -ENOMEM; | |
a98a3c3f SR |
2778 | out: |
2779 | max_tr.entries = global_trace.entries; | |
2780 | mutex_unlock(&trace_types_lock); | |
2781 | ||
2782 | return cnt; | |
2783 | } | |
2784 | ||
bc0c38d1 | 2785 | static struct file_operations tracing_max_lat_fops = { |
4bf39a94 IM |
2786 | .open = tracing_open_generic, |
2787 | .read = tracing_max_lat_read, | |
2788 | .write = tracing_max_lat_write, | |
bc0c38d1 SR |
2789 | }; |
2790 | ||
2791 | static struct file_operations tracing_ctrl_fops = { | |
4bf39a94 IM |
2792 | .open = tracing_open_generic, |
2793 | .read = tracing_ctrl_read, | |
2794 | .write = tracing_ctrl_write, | |
bc0c38d1 SR |
2795 | }; |
2796 | ||
2797 | static struct file_operations set_tracer_fops = { | |
4bf39a94 IM |
2798 | .open = tracing_open_generic, |
2799 | .read = tracing_set_trace_read, | |
2800 | .write = tracing_set_trace_write, | |
bc0c38d1 SR |
2801 | }; |
2802 | ||
b3806b43 | 2803 | static struct file_operations tracing_pipe_fops = { |
4bf39a94 | 2804 | .open = tracing_open_pipe, |
2a2cc8f7 | 2805 | .poll = tracing_poll_pipe, |
4bf39a94 IM |
2806 | .read = tracing_read_pipe, |
2807 | .release = tracing_release_pipe, | |
b3806b43 SR |
2808 | }; |
2809 | ||
a98a3c3f SR |
2810 | static struct file_operations tracing_entries_fops = { |
2811 | .open = tracing_open_generic, | |
2812 | .read = tracing_entries_read, | |
2813 | .write = tracing_entries_write, | |
2814 | }; | |
2815 | ||
bc0c38d1 SR |
2816 | #ifdef CONFIG_DYNAMIC_FTRACE |
2817 | ||
2818 | static ssize_t | |
2819 | tracing_read_long(struct file *filp, char __user *ubuf, | |
2820 | size_t cnt, loff_t *ppos) | |
2821 | { | |
2822 | unsigned long *p = filp->private_data; | |
2823 | char buf[64]; | |
2824 | int r; | |
2825 | ||
2826 | r = sprintf(buf, "%ld\n", *p); | |
4bf39a94 IM |
2827 | |
2828 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
bc0c38d1 SR |
2829 | } |
2830 | ||
2831 | static struct file_operations tracing_read_long_fops = { | |
4bf39a94 IM |
2832 | .open = tracing_open_generic, |
2833 | .read = tracing_read_long, | |
bc0c38d1 SR |
2834 | }; |
2835 | #endif | |
2836 | ||
2837 | static struct dentry *d_tracer; | |
2838 | ||
2839 | struct dentry *tracing_init_dentry(void) | |
2840 | { | |
2841 | static int once; | |
2842 | ||
2843 | if (d_tracer) | |
2844 | return d_tracer; | |
2845 | ||
2846 | d_tracer = debugfs_create_dir("tracing", NULL); | |
2847 | ||
2848 | if (!d_tracer && !once) { | |
2849 | once = 1; | |
2850 | pr_warning("Could not create debugfs directory 'tracing'\n"); | |
2851 | return NULL; | |
2852 | } | |
2853 | ||
2854 | return d_tracer; | |
2855 | } | |
2856 | ||
60a11774 SR |
2857 | #ifdef CONFIG_FTRACE_SELFTEST |
2858 | /* Let selftest have access to static functions in this file */ | |
2859 | #include "trace_selftest.c" | |
2860 | #endif | |
2861 | ||
bc0c38d1 SR |
2862 | static __init void tracer_init_debugfs(void) |
2863 | { | |
2864 | struct dentry *d_tracer; | |
2865 | struct dentry *entry; | |
2866 | ||
2867 | d_tracer = tracing_init_dentry(); | |
2868 | ||
2869 | entry = debugfs_create_file("tracing_enabled", 0644, d_tracer, | |
2870 | &global_trace, &tracing_ctrl_fops); | |
2871 | if (!entry) | |
2872 | pr_warning("Could not create debugfs 'tracing_enabled' entry\n"); | |
2873 | ||
2874 | entry = debugfs_create_file("iter_ctrl", 0644, d_tracer, | |
2875 | NULL, &tracing_iter_fops); | |
2876 | if (!entry) | |
2877 | pr_warning("Could not create debugfs 'iter_ctrl' entry\n"); | |
2878 | ||
c7078de1 IM |
2879 | entry = debugfs_create_file("tracing_cpumask", 0644, d_tracer, |
2880 | NULL, &tracing_cpumask_fops); | |
2881 | if (!entry) | |
2882 | pr_warning("Could not create debugfs 'tracing_cpumask' entry\n"); | |
2883 | ||
bc0c38d1 SR |
2884 | entry = debugfs_create_file("latency_trace", 0444, d_tracer, |
2885 | &global_trace, &tracing_lt_fops); | |
2886 | if (!entry) | |
2887 | pr_warning("Could not create debugfs 'latency_trace' entry\n"); | |
2888 | ||
2889 | entry = debugfs_create_file("trace", 0444, d_tracer, | |
2890 | &global_trace, &tracing_fops); | |
2891 | if (!entry) | |
2892 | pr_warning("Could not create debugfs 'trace' entry\n"); | |
2893 | ||
2894 | entry = debugfs_create_file("available_tracers", 0444, d_tracer, | |
2895 | &global_trace, &show_traces_fops); | |
2896 | if (!entry) | |
2897 | pr_warning("Could not create debugfs 'trace' entry\n"); | |
2898 | ||
2899 | entry = debugfs_create_file("current_tracer", 0444, d_tracer, | |
2900 | &global_trace, &set_tracer_fops); | |
2901 | if (!entry) | |
2902 | pr_warning("Could not create debugfs 'trace' entry\n"); | |
2903 | ||
2904 | entry = debugfs_create_file("tracing_max_latency", 0644, d_tracer, | |
2905 | &tracing_max_latency, | |
2906 | &tracing_max_lat_fops); | |
2907 | if (!entry) | |
2908 | pr_warning("Could not create debugfs " | |
2909 | "'tracing_max_latency' entry\n"); | |
2910 | ||
2911 | entry = debugfs_create_file("tracing_thresh", 0644, d_tracer, | |
2912 | &tracing_thresh, &tracing_max_lat_fops); | |
2913 | if (!entry) | |
2914 | pr_warning("Could not create debugfs " | |
2915 | "'tracing_threash' entry\n"); | |
7bd2f24c IM |
2916 | entry = debugfs_create_file("README", 0644, d_tracer, |
2917 | NULL, &tracing_readme_fops); | |
2918 | if (!entry) | |
2919 | pr_warning("Could not create debugfs 'README' entry\n"); | |
2920 | ||
b3806b43 SR |
2921 | entry = debugfs_create_file("trace_pipe", 0644, d_tracer, |
2922 | NULL, &tracing_pipe_fops); | |
2923 | if (!entry) | |
2924 | pr_warning("Could not create debugfs " | |
2925 | "'tracing_threash' entry\n"); | |
bc0c38d1 | 2926 | |
a98a3c3f SR |
2927 | entry = debugfs_create_file("trace_entries", 0644, d_tracer, |
2928 | &global_trace, &tracing_entries_fops); | |
2929 | if (!entry) | |
2930 | pr_warning("Could not create debugfs " | |
2931 | "'tracing_threash' entry\n"); | |
2932 | ||
bc0c38d1 SR |
2933 | #ifdef CONFIG_DYNAMIC_FTRACE |
2934 | entry = debugfs_create_file("dyn_ftrace_total_info", 0444, d_tracer, | |
2935 | &ftrace_update_tot_cnt, | |
2936 | &tracing_read_long_fops); | |
2937 | if (!entry) | |
2938 | pr_warning("Could not create debugfs " | |
2939 | "'dyn_ftrace_total_info' entry\n"); | |
2940 | #endif | |
d618b3e6 IM |
2941 | #ifdef CONFIG_SYSPROF_TRACER |
2942 | init_tracer_sysprof_debugfs(d_tracer); | |
2943 | #endif | |
bc0c38d1 SR |
2944 | } |
2945 | ||
4c11d7ae | 2946 | static int trace_alloc_page(void) |
bc0c38d1 | 2947 | { |
4c11d7ae | 2948 | struct trace_array_cpu *data; |
4c11d7ae SR |
2949 | struct page *page, *tmp; |
2950 | LIST_HEAD(pages); | |
c7aafc54 | 2951 | void *array; |
3eefae99 | 2952 | unsigned pages_allocated = 0; |
4c11d7ae SR |
2953 | int i; |
2954 | ||
2955 | /* first allocate a page for each CPU */ | |
ab46428c | 2956 | for_each_tracing_cpu(i) { |
4c11d7ae SR |
2957 | array = (void *)__get_free_page(GFP_KERNEL); |
2958 | if (array == NULL) { | |
2959 | printk(KERN_ERR "tracer: failed to allocate page" | |
2960 | "for trace buffer!\n"); | |
2961 | goto free_pages; | |
2962 | } | |
2963 | ||
3eefae99 | 2964 | pages_allocated++; |
4c11d7ae SR |
2965 | page = virt_to_page(array); |
2966 | list_add(&page->lru, &pages); | |
2967 | ||
2968 | /* Only allocate if we are actually using the max trace */ | |
2969 | #ifdef CONFIG_TRACER_MAX_TRACE | |
2970 | array = (void *)__get_free_page(GFP_KERNEL); | |
2971 | if (array == NULL) { | |
2972 | printk(KERN_ERR "tracer: failed to allocate page" | |
2973 | "for trace buffer!\n"); | |
2974 | goto free_pages; | |
2975 | } | |
3eefae99 | 2976 | pages_allocated++; |
4c11d7ae SR |
2977 | page = virt_to_page(array); |
2978 | list_add(&page->lru, &pages); | |
2979 | #endif | |
2980 | } | |
2981 | ||
2982 | /* Now that we successfully allocate a page per CPU, add them */ | |
ab46428c | 2983 | for_each_tracing_cpu(i) { |
4c11d7ae SR |
2984 | data = global_trace.data[i]; |
2985 | page = list_entry(pages.next, struct page, lru); | |
c7aafc54 | 2986 | list_del_init(&page->lru); |
4c11d7ae SR |
2987 | list_add_tail(&page->lru, &data->trace_pages); |
2988 | ClearPageLRU(page); | |
2989 | ||
2990 | #ifdef CONFIG_TRACER_MAX_TRACE | |
2991 | data = max_tr.data[i]; | |
2992 | page = list_entry(pages.next, struct page, lru); | |
c7aafc54 | 2993 | list_del_init(&page->lru); |
4c11d7ae SR |
2994 | list_add_tail(&page->lru, &data->trace_pages); |
2995 | SetPageLRU(page); | |
2996 | #endif | |
2997 | } | |
3eefae99 | 2998 | tracing_pages_allocated += pages_allocated; |
4c11d7ae SR |
2999 | global_trace.entries += ENTRIES_PER_PAGE; |
3000 | ||
3001 | return 0; | |
3002 | ||
3003 | free_pages: | |
3004 | list_for_each_entry_safe(page, tmp, &pages, lru) { | |
c7aafc54 | 3005 | list_del_init(&page->lru); |
4c11d7ae SR |
3006 | __free_page(page); |
3007 | } | |
3008 | return -ENOMEM; | |
bc0c38d1 SR |
3009 | } |
3010 | ||
a98a3c3f SR |
3011 | static int trace_free_page(void) |
3012 | { | |
3013 | struct trace_array_cpu *data; | |
3014 | struct page *page; | |
3015 | struct list_head *p; | |
3016 | int i; | |
3017 | int ret = 0; | |
3018 | ||
3019 | /* free one page from each buffer */ | |
ab46428c | 3020 | for_each_tracing_cpu(i) { |
a98a3c3f SR |
3021 | data = global_trace.data[i]; |
3022 | p = data->trace_pages.next; | |
3023 | if (p == &data->trace_pages) { | |
3024 | /* should never happen */ | |
3025 | WARN_ON(1); | |
3026 | tracing_disabled = 1; | |
3027 | ret = -1; | |
3028 | break; | |
3029 | } | |
3030 | page = list_entry(p, struct page, lru); | |
3031 | ClearPageLRU(page); | |
3032 | list_del(&page->lru); | |
3eefae99 SR |
3033 | tracing_pages_allocated--; |
3034 | tracing_pages_allocated--; | |
a98a3c3f SR |
3035 | __free_page(page); |
3036 | ||
3037 | tracing_reset(data); | |
3038 | ||
3039 | #ifdef CONFIG_TRACER_MAX_TRACE | |
3040 | data = max_tr.data[i]; | |
3041 | p = data->trace_pages.next; | |
3042 | if (p == &data->trace_pages) { | |
3043 | /* should never happen */ | |
3044 | WARN_ON(1); | |
3045 | tracing_disabled = 1; | |
3046 | ret = -1; | |
3047 | break; | |
3048 | } | |
3049 | page = list_entry(p, struct page, lru); | |
3050 | ClearPageLRU(page); | |
3051 | list_del(&page->lru); | |
3052 | __free_page(page); | |
3053 | ||
3054 | tracing_reset(data); | |
3055 | #endif | |
3056 | } | |
3057 | global_trace.entries -= ENTRIES_PER_PAGE; | |
3058 | ||
3059 | return ret; | |
3060 | } | |
3061 | ||
bc0c38d1 SR |
3062 | __init static int tracer_alloc_buffers(void) |
3063 | { | |
4c11d7ae SR |
3064 | struct trace_array_cpu *data; |
3065 | void *array; | |
3066 | struct page *page; | |
3067 | int pages = 0; | |
60a11774 | 3068 | int ret = -ENOMEM; |
bc0c38d1 SR |
3069 | int i; |
3070 | ||
ab46428c SR |
3071 | /* TODO: make the number of buffers hot pluggable with CPUS */ |
3072 | tracing_nr_buffers = num_possible_cpus(); | |
3073 | tracing_buffer_mask = cpu_possible_map; | |
3074 | ||
4c11d7ae | 3075 | /* Allocate the first page for all buffers */ |
ab46428c | 3076 | for_each_tracing_cpu(i) { |
4c11d7ae | 3077 | data = global_trace.data[i] = &per_cpu(global_trace_cpu, i); |
bc0c38d1 SR |
3078 | max_tr.data[i] = &per_cpu(max_data, i); |
3079 | ||
4c11d7ae | 3080 | array = (void *)__get_free_page(GFP_KERNEL); |
bc0c38d1 | 3081 | if (array == NULL) { |
4c11d7ae SR |
3082 | printk(KERN_ERR "tracer: failed to allocate page" |
3083 | "for trace buffer!\n"); | |
bc0c38d1 SR |
3084 | goto free_buffers; |
3085 | } | |
4c11d7ae SR |
3086 | |
3087 | /* set the array to the list */ | |
3088 | INIT_LIST_HEAD(&data->trace_pages); | |
3089 | page = virt_to_page(array); | |
3090 | list_add(&page->lru, &data->trace_pages); | |
3091 | /* use the LRU flag to differentiate the two buffers */ | |
3092 | ClearPageLRU(page); | |
bc0c38d1 | 3093 | |
a98a3c3f SR |
3094 | data->lock = (raw_spinlock_t)__RAW_SPIN_LOCK_UNLOCKED; |
3095 | max_tr.data[i]->lock = (raw_spinlock_t)__RAW_SPIN_LOCK_UNLOCKED; | |
3096 | ||
bc0c38d1 SR |
3097 | /* Only allocate if we are actually using the max trace */ |
3098 | #ifdef CONFIG_TRACER_MAX_TRACE | |
4c11d7ae | 3099 | array = (void *)__get_free_page(GFP_KERNEL); |
bc0c38d1 | 3100 | if (array == NULL) { |
4c11d7ae SR |
3101 | printk(KERN_ERR "tracer: failed to allocate page" |
3102 | "for trace buffer!\n"); | |
bc0c38d1 SR |
3103 | goto free_buffers; |
3104 | } | |
4c11d7ae SR |
3105 | |
3106 | INIT_LIST_HEAD(&max_tr.data[i]->trace_pages); | |
3107 | page = virt_to_page(array); | |
3108 | list_add(&page->lru, &max_tr.data[i]->trace_pages); | |
3109 | SetPageLRU(page); | |
bc0c38d1 SR |
3110 | #endif |
3111 | } | |
3112 | ||
3113 | /* | |
3114 | * Since we allocate by orders of pages, we may be able to | |
3115 | * round up a bit. | |
3116 | */ | |
4c11d7ae | 3117 | global_trace.entries = ENTRIES_PER_PAGE; |
4c11d7ae SR |
3118 | pages++; |
3119 | ||
3120 | while (global_trace.entries < trace_nr_entries) { | |
3121 | if (trace_alloc_page()) | |
3122 | break; | |
3123 | pages++; | |
3124 | } | |
89b2f978 | 3125 | max_tr.entries = global_trace.entries; |
bc0c38d1 | 3126 | |
20764ff1 JS |
3127 | pr_info("tracer: %d pages allocated for %ld entries of %ld bytes\n", |
3128 | pages, trace_nr_entries, (long)TRACE_ENTRY_SIZE); | |
bc0c38d1 SR |
3129 | pr_info(" actual entries %ld\n", global_trace.entries); |
3130 | ||
3131 | tracer_init_debugfs(); | |
3132 | ||
3133 | trace_init_cmdlines(); | |
3134 | ||
3135 | register_tracer(&no_tracer); | |
3136 | current_trace = &no_tracer; | |
3137 | ||
60a11774 | 3138 | /* All seems OK, enable tracing */ |
4902f884 | 3139 | global_trace.ctrl = tracer_enabled; |
60a11774 SR |
3140 | tracing_disabled = 0; |
3141 | ||
bc0c38d1 SR |
3142 | return 0; |
3143 | ||
3144 | free_buffers: | |
3145 | for (i-- ; i >= 0; i--) { | |
4c11d7ae | 3146 | struct page *page, *tmp; |
bc0c38d1 SR |
3147 | struct trace_array_cpu *data = global_trace.data[i]; |
3148 | ||
c7aafc54 | 3149 | if (data) { |
4c11d7ae SR |
3150 | list_for_each_entry_safe(page, tmp, |
3151 | &data->trace_pages, lru) { | |
c7aafc54 | 3152 | list_del_init(&page->lru); |
4c11d7ae SR |
3153 | __free_page(page); |
3154 | } | |
bc0c38d1 SR |
3155 | } |
3156 | ||
3157 | #ifdef CONFIG_TRACER_MAX_TRACE | |
3158 | data = max_tr.data[i]; | |
c7aafc54 | 3159 | if (data) { |
4c11d7ae SR |
3160 | list_for_each_entry_safe(page, tmp, |
3161 | &data->trace_pages, lru) { | |
c7aafc54 | 3162 | list_del_init(&page->lru); |
4c11d7ae SR |
3163 | __free_page(page); |
3164 | } | |
bc0c38d1 SR |
3165 | } |
3166 | #endif | |
3167 | } | |
60a11774 | 3168 | return ret; |
bc0c38d1 | 3169 | } |
60a11774 | 3170 | fs_initcall(tracer_alloc_buffers); |