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Commit | Line | Data |
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bc0c38d1 SR |
1 | /* |
2 | * ring buffer based function tracer | |
3 | * | |
4 | * Copyright (C) 2007-2008 Steven Rostedt <srostedt@redhat.com> | |
5 | * Copyright (C) 2008 Ingo Molnar <mingo@redhat.com> | |
6 | * | |
7 | * Originally taken from the RT patch by: | |
8 | * Arnaldo Carvalho de Melo <acme@redhat.com> | |
9 | * | |
10 | * Based on code from the latency_tracer, that is: | |
11 | * Copyright (C) 2004-2006 Ingo Molnar | |
12 | * Copyright (C) 2004 William Lee Irwin III | |
13 | */ | |
14 | #include <linux/utsrelease.h> | |
15 | #include <linux/kallsyms.h> | |
16 | #include <linux/seq_file.h> | |
3f5a54e3 | 17 | #include <linux/notifier.h> |
bc0c38d1 | 18 | #include <linux/debugfs.h> |
4c11d7ae | 19 | #include <linux/pagemap.h> |
bc0c38d1 SR |
20 | #include <linux/hardirq.h> |
21 | #include <linux/linkage.h> | |
22 | #include <linux/uaccess.h> | |
23 | #include <linux/ftrace.h> | |
24 | #include <linux/module.h> | |
25 | #include <linux/percpu.h> | |
3f5a54e3 | 26 | #include <linux/kdebug.h> |
bc0c38d1 SR |
27 | #include <linux/ctype.h> |
28 | #include <linux/init.h> | |
2a2cc8f7 | 29 | #include <linux/poll.h> |
bc0c38d1 SR |
30 | #include <linux/gfp.h> |
31 | #include <linux/fs.h> | |
76094a2c | 32 | #include <linux/kprobes.h> |
3eefae99 | 33 | #include <linux/writeback.h> |
bc0c38d1 | 34 | |
86387f7e IM |
35 | #include <linux/stacktrace.h> |
36 | ||
bc0c38d1 SR |
37 | #include "trace.h" |
38 | ||
39 | unsigned long __read_mostly tracing_max_latency = (cycle_t)ULONG_MAX; | |
40 | unsigned long __read_mostly tracing_thresh; | |
41 | ||
ab46428c SR |
42 | static unsigned long __read_mostly tracing_nr_buffers; |
43 | static cpumask_t __read_mostly tracing_buffer_mask; | |
44 | ||
45 | #define for_each_tracing_cpu(cpu) \ | |
46 | for_each_cpu_mask(cpu, tracing_buffer_mask) | |
47 | ||
a98a3c3f SR |
48 | static int trace_alloc_page(void); |
49 | static int trace_free_page(void); | |
50 | ||
60a11774 SR |
51 | static int tracing_disabled = 1; |
52 | ||
3eefae99 SR |
53 | static unsigned long tracing_pages_allocated; |
54 | ||
72829bc3 | 55 | long |
bc0c38d1 SR |
56 | ns2usecs(cycle_t nsec) |
57 | { | |
58 | nsec += 500; | |
59 | do_div(nsec, 1000); | |
60 | return nsec; | |
61 | } | |
62 | ||
e309b41d | 63 | cycle_t ftrace_now(int cpu) |
750ed1a4 | 64 | { |
0fd9e0da | 65 | return cpu_clock(cpu); |
750ed1a4 IM |
66 | } |
67 | ||
4fcdae83 SR |
68 | /* |
69 | * The global_trace is the descriptor that holds the tracing | |
70 | * buffers for the live tracing. For each CPU, it contains | |
71 | * a link list of pages that will store trace entries. The | |
72 | * page descriptor of the pages in the memory is used to hold | |
73 | * the link list by linking the lru item in the page descriptor | |
74 | * to each of the pages in the buffer per CPU. | |
75 | * | |
76 | * For each active CPU there is a data field that holds the | |
77 | * pages for the buffer for that CPU. Each CPU has the same number | |
78 | * of pages allocated for its buffer. | |
79 | */ | |
bc0c38d1 SR |
80 | static struct trace_array global_trace; |
81 | ||
82 | static DEFINE_PER_CPU(struct trace_array_cpu, global_trace_cpu); | |
83 | ||
4fcdae83 SR |
84 | /* |
85 | * The max_tr is used to snapshot the global_trace when a maximum | |
86 | * latency is reached. Some tracers will use this to store a maximum | |
87 | * trace while it continues examining live traces. | |
88 | * | |
89 | * The buffers for the max_tr are set up the same as the global_trace. | |
90 | * When a snapshot is taken, the link list of the max_tr is swapped | |
91 | * with the link list of the global_trace and the buffers are reset for | |
92 | * the global_trace so the tracing can continue. | |
93 | */ | |
bc0c38d1 SR |
94 | static struct trace_array max_tr; |
95 | ||
96 | static DEFINE_PER_CPU(struct trace_array_cpu, max_data); | |
97 | ||
4fcdae83 | 98 | /* tracer_enabled is used to toggle activation of a tracer */ |
26994ead | 99 | static int tracer_enabled = 1; |
4fcdae83 | 100 | |
60bc0800 SR |
101 | /* function tracing enabled */ |
102 | int ftrace_function_enabled; | |
103 | ||
4fcdae83 SR |
104 | /* |
105 | * trace_nr_entries is the number of entries that is allocated | |
106 | * for a buffer. Note, the number of entries is always rounded | |
107 | * to ENTRIES_PER_PAGE. | |
3f5a54e3 SR |
108 | * |
109 | * This number is purposely set to a low number of 16384. | |
110 | * If the dump on oops happens, it will be much appreciated | |
111 | * to not have to wait for all that output. Anyway this can be | |
112 | * boot time and run time configurable. | |
4fcdae83 | 113 | */ |
3f5a54e3 SR |
114 | #define TRACE_ENTRIES_DEFAULT 16384UL |
115 | ||
116 | static unsigned long trace_nr_entries = TRACE_ENTRIES_DEFAULT; | |
bc0c38d1 | 117 | |
4fcdae83 | 118 | /* trace_types holds a link list of available tracers. */ |
bc0c38d1 | 119 | static struct tracer *trace_types __read_mostly; |
4fcdae83 SR |
120 | |
121 | /* current_trace points to the tracer that is currently active */ | |
bc0c38d1 | 122 | static struct tracer *current_trace __read_mostly; |
4fcdae83 SR |
123 | |
124 | /* | |
125 | * max_tracer_type_len is used to simplify the allocating of | |
126 | * buffers to read userspace tracer names. We keep track of | |
127 | * the longest tracer name registered. | |
128 | */ | |
bc0c38d1 SR |
129 | static int max_tracer_type_len; |
130 | ||
4fcdae83 SR |
131 | /* |
132 | * trace_types_lock is used to protect the trace_types list. | |
133 | * This lock is also used to keep user access serialized. | |
134 | * Accesses from userspace will grab this lock while userspace | |
135 | * activities happen inside the kernel. | |
136 | */ | |
bc0c38d1 | 137 | static DEFINE_MUTEX(trace_types_lock); |
4fcdae83 SR |
138 | |
139 | /* trace_wait is a waitqueue for tasks blocked on trace_poll */ | |
4e655519 IM |
140 | static DECLARE_WAIT_QUEUE_HEAD(trace_wait); |
141 | ||
4fcdae83 | 142 | /* trace_flags holds iter_ctrl options */ |
4e655519 IM |
143 | unsigned long trace_flags = TRACE_ITER_PRINT_PARENT; |
144 | ||
2b1bce17 AG |
145 | static notrace void no_trace_init(struct trace_array *tr) |
146 | { | |
147 | int cpu; | |
148 | ||
60bc0800 | 149 | ftrace_function_enabled = 0; |
2b1bce17 AG |
150 | if(tr->ctrl) |
151 | for_each_online_cpu(cpu) | |
152 | tracing_reset(tr->data[cpu]); | |
153 | tracer_enabled = 0; | |
154 | } | |
155 | ||
156 | /* dummy trace to disable tracing */ | |
157 | static struct tracer no_tracer __read_mostly = { | |
158 | .name = "none", | |
159 | .init = no_trace_init | |
160 | }; | |
161 | ||
162 | ||
4fcdae83 SR |
163 | /** |
164 | * trace_wake_up - wake up tasks waiting for trace input | |
165 | * | |
166 | * Simply wakes up any task that is blocked on the trace_wait | |
167 | * queue. These is used with trace_poll for tasks polling the trace. | |
168 | */ | |
4e655519 IM |
169 | void trace_wake_up(void) |
170 | { | |
017730c1 IM |
171 | /* |
172 | * The runqueue_is_locked() can fail, but this is the best we | |
173 | * have for now: | |
174 | */ | |
175 | if (!(trace_flags & TRACE_ITER_BLOCK) && !runqueue_is_locked()) | |
4e655519 IM |
176 | wake_up(&trace_wait); |
177 | } | |
bc0c38d1 | 178 | |
4c11d7ae SR |
179 | #define ENTRIES_PER_PAGE (PAGE_SIZE / sizeof(struct trace_entry)) |
180 | ||
bc0c38d1 SR |
181 | static int __init set_nr_entries(char *str) |
182 | { | |
c6caeeb1 SR |
183 | unsigned long nr_entries; |
184 | int ret; | |
185 | ||
bc0c38d1 SR |
186 | if (!str) |
187 | return 0; | |
c6caeeb1 SR |
188 | ret = strict_strtoul(str, 0, &nr_entries); |
189 | /* nr_entries can not be zero */ | |
190 | if (ret < 0 || nr_entries == 0) | |
191 | return 0; | |
192 | trace_nr_entries = nr_entries; | |
bc0c38d1 SR |
193 | return 1; |
194 | } | |
195 | __setup("trace_entries=", set_nr_entries); | |
196 | ||
57f50be1 SR |
197 | unsigned long nsecs_to_usecs(unsigned long nsecs) |
198 | { | |
199 | return nsecs / 1000; | |
200 | } | |
201 | ||
4fcdae83 SR |
202 | /* |
203 | * trace_flag_type is an enumeration that holds different | |
204 | * states when a trace occurs. These are: | |
205 | * IRQS_OFF - interrupts were disabled | |
206 | * NEED_RESCED - reschedule is requested | |
207 | * HARDIRQ - inside an interrupt handler | |
208 | * SOFTIRQ - inside a softirq handler | |
dd0e545f | 209 | * CONT - multiple entries hold the trace item |
4fcdae83 | 210 | */ |
bc0c38d1 SR |
211 | enum trace_flag_type { |
212 | TRACE_FLAG_IRQS_OFF = 0x01, | |
213 | TRACE_FLAG_NEED_RESCHED = 0x02, | |
214 | TRACE_FLAG_HARDIRQ = 0x04, | |
215 | TRACE_FLAG_SOFTIRQ = 0x08, | |
dd0e545f | 216 | TRACE_FLAG_CONT = 0x10, |
bc0c38d1 SR |
217 | }; |
218 | ||
4fcdae83 SR |
219 | /* |
220 | * TRACE_ITER_SYM_MASK masks the options in trace_flags that | |
221 | * control the output of kernel symbols. | |
222 | */ | |
bc0c38d1 SR |
223 | #define TRACE_ITER_SYM_MASK \ |
224 | (TRACE_ITER_PRINT_PARENT|TRACE_ITER_SYM_OFFSET|TRACE_ITER_SYM_ADDR) | |
225 | ||
4fcdae83 | 226 | /* These must match the bit postions in trace_iterator_flags */ |
bc0c38d1 SR |
227 | static const char *trace_options[] = { |
228 | "print-parent", | |
229 | "sym-offset", | |
230 | "sym-addr", | |
231 | "verbose", | |
f9896bf3 | 232 | "raw", |
5e3ca0ec | 233 | "hex", |
cb0f12aa | 234 | "bin", |
2a2cc8f7 | 235 | "block", |
86387f7e | 236 | "stacktrace", |
4ac3ba41 | 237 | "sched-tree", |
bc0c38d1 SR |
238 | NULL |
239 | }; | |
240 | ||
4fcdae83 SR |
241 | /* |
242 | * ftrace_max_lock is used to protect the swapping of buffers | |
243 | * when taking a max snapshot. The buffers themselves are | |
244 | * protected by per_cpu spinlocks. But the action of the swap | |
245 | * needs its own lock. | |
246 | * | |
247 | * This is defined as a raw_spinlock_t in order to help | |
248 | * with performance when lockdep debugging is enabled. | |
249 | */ | |
92205c23 SR |
250 | static raw_spinlock_t ftrace_max_lock = |
251 | (raw_spinlock_t)__RAW_SPIN_LOCK_UNLOCKED; | |
bc0c38d1 SR |
252 | |
253 | /* | |
254 | * Copy the new maximum trace into the separate maximum-trace | |
255 | * structure. (this way the maximum trace is permanently saved, | |
256 | * for later retrieval via /debugfs/tracing/latency_trace) | |
257 | */ | |
e309b41d | 258 | static void |
bc0c38d1 SR |
259 | __update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) |
260 | { | |
261 | struct trace_array_cpu *data = tr->data[cpu]; | |
262 | ||
263 | max_tr.cpu = cpu; | |
264 | max_tr.time_start = data->preempt_timestamp; | |
265 | ||
266 | data = max_tr.data[cpu]; | |
267 | data->saved_latency = tracing_max_latency; | |
268 | ||
269 | memcpy(data->comm, tsk->comm, TASK_COMM_LEN); | |
270 | data->pid = tsk->pid; | |
271 | data->uid = tsk->uid; | |
272 | data->nice = tsk->static_prio - 20 - MAX_RT_PRIO; | |
273 | data->policy = tsk->policy; | |
274 | data->rt_priority = tsk->rt_priority; | |
275 | ||
276 | /* record this tasks comm */ | |
277 | tracing_record_cmdline(current); | |
278 | } | |
279 | ||
19384c03 SR |
280 | #define CHECK_COND(cond) \ |
281 | if (unlikely(cond)) { \ | |
282 | tracing_disabled = 1; \ | |
283 | WARN_ON(1); \ | |
284 | return -1; \ | |
285 | } | |
286 | ||
4fcdae83 SR |
287 | /** |
288 | * check_pages - integrity check of trace buffers | |
289 | * | |
290 | * As a safty measure we check to make sure the data pages have not | |
19384c03 | 291 | * been corrupted. |
4fcdae83 | 292 | */ |
19384c03 | 293 | int check_pages(struct trace_array_cpu *data) |
c7aafc54 IM |
294 | { |
295 | struct page *page, *tmp; | |
296 | ||
19384c03 SR |
297 | CHECK_COND(data->trace_pages.next->prev != &data->trace_pages); |
298 | CHECK_COND(data->trace_pages.prev->next != &data->trace_pages); | |
c7aafc54 IM |
299 | |
300 | list_for_each_entry_safe(page, tmp, &data->trace_pages, lru) { | |
19384c03 SR |
301 | CHECK_COND(page->lru.next->prev != &page->lru); |
302 | CHECK_COND(page->lru.prev->next != &page->lru); | |
c7aafc54 | 303 | } |
19384c03 SR |
304 | |
305 | return 0; | |
c7aafc54 IM |
306 | } |
307 | ||
4fcdae83 SR |
308 | /** |
309 | * head_page - page address of the first page in per_cpu buffer. | |
310 | * | |
311 | * head_page returns the page address of the first page in | |
312 | * a per_cpu buffer. This also preforms various consistency | |
313 | * checks to make sure the buffer has not been corrupted. | |
314 | */ | |
c7aafc54 IM |
315 | void *head_page(struct trace_array_cpu *data) |
316 | { | |
317 | struct page *page; | |
318 | ||
c7aafc54 IM |
319 | if (list_empty(&data->trace_pages)) |
320 | return NULL; | |
321 | ||
322 | page = list_entry(data->trace_pages.next, struct page, lru); | |
323 | BUG_ON(&page->lru == &data->trace_pages); | |
324 | ||
325 | return page_address(page); | |
326 | } | |
327 | ||
4fcdae83 SR |
328 | /** |
329 | * trace_seq_printf - sequence printing of trace information | |
330 | * @s: trace sequence descriptor | |
331 | * @fmt: printf format string | |
332 | * | |
333 | * The tracer may use either sequence operations or its own | |
334 | * copy to user routines. To simplify formating of a trace | |
335 | * trace_seq_printf is used to store strings into a special | |
336 | * buffer (@s). Then the output may be either used by | |
337 | * the sequencer or pulled into another buffer. | |
338 | */ | |
72829bc3 | 339 | int |
214023c3 SR |
340 | trace_seq_printf(struct trace_seq *s, const char *fmt, ...) |
341 | { | |
342 | int len = (PAGE_SIZE - 1) - s->len; | |
343 | va_list ap; | |
b3806b43 | 344 | int ret; |
214023c3 SR |
345 | |
346 | if (!len) | |
347 | return 0; | |
348 | ||
349 | va_start(ap, fmt); | |
b3806b43 | 350 | ret = vsnprintf(s->buffer + s->len, len, fmt, ap); |
214023c3 SR |
351 | va_end(ap); |
352 | ||
b3806b43 | 353 | /* If we can't write it all, don't bother writing anything */ |
72829bc3 | 354 | if (ret >= len) |
b3806b43 SR |
355 | return 0; |
356 | ||
357 | s->len += ret; | |
214023c3 SR |
358 | |
359 | return len; | |
360 | } | |
361 | ||
4fcdae83 SR |
362 | /** |
363 | * trace_seq_puts - trace sequence printing of simple string | |
364 | * @s: trace sequence descriptor | |
365 | * @str: simple string to record | |
366 | * | |
367 | * The tracer may use either the sequence operations or its own | |
368 | * copy to user routines. This function records a simple string | |
369 | * into a special buffer (@s) for later retrieval by a sequencer | |
370 | * or other mechanism. | |
371 | */ | |
e309b41d | 372 | static int |
214023c3 SR |
373 | trace_seq_puts(struct trace_seq *s, const char *str) |
374 | { | |
375 | int len = strlen(str); | |
376 | ||
377 | if (len > ((PAGE_SIZE - 1) - s->len)) | |
b3806b43 | 378 | return 0; |
214023c3 SR |
379 | |
380 | memcpy(s->buffer + s->len, str, len); | |
381 | s->len += len; | |
382 | ||
383 | return len; | |
384 | } | |
385 | ||
e309b41d | 386 | static int |
214023c3 SR |
387 | trace_seq_putc(struct trace_seq *s, unsigned char c) |
388 | { | |
389 | if (s->len >= (PAGE_SIZE - 1)) | |
390 | return 0; | |
391 | ||
392 | s->buffer[s->len++] = c; | |
393 | ||
394 | return 1; | |
395 | } | |
396 | ||
e309b41d | 397 | static int |
cb0f12aa IM |
398 | trace_seq_putmem(struct trace_seq *s, void *mem, size_t len) |
399 | { | |
400 | if (len > ((PAGE_SIZE - 1) - s->len)) | |
401 | return 0; | |
402 | ||
403 | memcpy(s->buffer + s->len, mem, len); | |
404 | s->len += len; | |
405 | ||
406 | return len; | |
407 | } | |
408 | ||
5e3ca0ec | 409 | #define HEX_CHARS 17 |
93dcc6ea | 410 | static const char hex2asc[] = "0123456789abcdef"; |
5e3ca0ec | 411 | |
e309b41d | 412 | static int |
5e3ca0ec IM |
413 | trace_seq_putmem_hex(struct trace_seq *s, void *mem, size_t len) |
414 | { | |
415 | unsigned char hex[HEX_CHARS]; | |
93dcc6ea | 416 | unsigned char *data = mem; |
5e3ca0ec IM |
417 | unsigned char byte; |
418 | int i, j; | |
419 | ||
420 | BUG_ON(len >= HEX_CHARS); | |
421 | ||
5e3ca0ec IM |
422 | #ifdef __BIG_ENDIAN |
423 | for (i = 0, j = 0; i < len; i++) { | |
424 | #else | |
425 | for (i = len-1, j = 0; i >= 0; i--) { | |
426 | #endif | |
427 | byte = data[i]; | |
428 | ||
93dcc6ea TG |
429 | hex[j++] = hex2asc[byte & 0x0f]; |
430 | hex[j++] = hex2asc[byte >> 4]; | |
5e3ca0ec | 431 | } |
93dcc6ea | 432 | hex[j++] = ' '; |
5e3ca0ec IM |
433 | |
434 | return trace_seq_putmem(s, hex, j); | |
435 | } | |
436 | ||
e309b41d | 437 | static void |
214023c3 SR |
438 | trace_seq_reset(struct trace_seq *s) |
439 | { | |
440 | s->len = 0; | |
6c6c2796 PP |
441 | s->readpos = 0; |
442 | } | |
443 | ||
444 | ssize_t trace_seq_to_user(struct trace_seq *s, char __user *ubuf, size_t cnt) | |
445 | { | |
446 | int len; | |
447 | int ret; | |
448 | ||
449 | if (s->len <= s->readpos) | |
450 | return -EBUSY; | |
451 | ||
452 | len = s->len - s->readpos; | |
453 | if (cnt > len) | |
454 | cnt = len; | |
455 | ret = copy_to_user(ubuf, s->buffer + s->readpos, cnt); | |
456 | if (ret) | |
457 | return -EFAULT; | |
458 | ||
459 | s->readpos += len; | |
460 | return cnt; | |
214023c3 SR |
461 | } |
462 | ||
e309b41d | 463 | static void |
214023c3 SR |
464 | trace_print_seq(struct seq_file *m, struct trace_seq *s) |
465 | { | |
466 | int len = s->len >= PAGE_SIZE ? PAGE_SIZE - 1 : s->len; | |
467 | ||
468 | s->buffer[len] = 0; | |
469 | seq_puts(m, s->buffer); | |
470 | ||
471 | trace_seq_reset(s); | |
472 | } | |
473 | ||
4fcdae83 SR |
474 | /* |
475 | * flip the trace buffers between two trace descriptors. | |
476 | * This usually is the buffers between the global_trace and | |
477 | * the max_tr to record a snapshot of a current trace. | |
478 | * | |
479 | * The ftrace_max_lock must be held. | |
480 | */ | |
e309b41d | 481 | static void |
c7aafc54 IM |
482 | flip_trace(struct trace_array_cpu *tr1, struct trace_array_cpu *tr2) |
483 | { | |
484 | struct list_head flip_pages; | |
485 | ||
486 | INIT_LIST_HEAD(&flip_pages); | |
487 | ||
93a588f4 | 488 | memcpy(&tr1->trace_head_idx, &tr2->trace_head_idx, |
c7aafc54 | 489 | sizeof(struct trace_array_cpu) - |
93a588f4 | 490 | offsetof(struct trace_array_cpu, trace_head_idx)); |
c7aafc54 IM |
491 | |
492 | check_pages(tr1); | |
493 | check_pages(tr2); | |
494 | list_splice_init(&tr1->trace_pages, &flip_pages); | |
495 | list_splice_init(&tr2->trace_pages, &tr1->trace_pages); | |
496 | list_splice_init(&flip_pages, &tr2->trace_pages); | |
497 | BUG_ON(!list_empty(&flip_pages)); | |
498 | check_pages(tr1); | |
499 | check_pages(tr2); | |
500 | } | |
501 | ||
4fcdae83 SR |
502 | /** |
503 | * update_max_tr - snapshot all trace buffers from global_trace to max_tr | |
504 | * @tr: tracer | |
505 | * @tsk: the task with the latency | |
506 | * @cpu: The cpu that initiated the trace. | |
507 | * | |
508 | * Flip the buffers between the @tr and the max_tr and record information | |
509 | * about which task was the cause of this latency. | |
510 | */ | |
e309b41d | 511 | void |
bc0c38d1 SR |
512 | update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) |
513 | { | |
514 | struct trace_array_cpu *data; | |
bc0c38d1 SR |
515 | int i; |
516 | ||
4c11d7ae | 517 | WARN_ON_ONCE(!irqs_disabled()); |
92205c23 | 518 | __raw_spin_lock(&ftrace_max_lock); |
bc0c38d1 | 519 | /* clear out all the previous traces */ |
ab46428c | 520 | for_each_tracing_cpu(i) { |
bc0c38d1 | 521 | data = tr->data[i]; |
c7aafc54 | 522 | flip_trace(max_tr.data[i], data); |
89b2f978 | 523 | tracing_reset(data); |
bc0c38d1 SR |
524 | } |
525 | ||
526 | __update_max_tr(tr, tsk, cpu); | |
92205c23 | 527 | __raw_spin_unlock(&ftrace_max_lock); |
bc0c38d1 SR |
528 | } |
529 | ||
530 | /** | |
531 | * update_max_tr_single - only copy one trace over, and reset the rest | |
532 | * @tr - tracer | |
533 | * @tsk - task with the latency | |
534 | * @cpu - the cpu of the buffer to copy. | |
4fcdae83 SR |
535 | * |
536 | * Flip the trace of a single CPU buffer between the @tr and the max_tr. | |
bc0c38d1 | 537 | */ |
e309b41d | 538 | void |
bc0c38d1 SR |
539 | update_max_tr_single(struct trace_array *tr, struct task_struct *tsk, int cpu) |
540 | { | |
541 | struct trace_array_cpu *data = tr->data[cpu]; | |
bc0c38d1 SR |
542 | int i; |
543 | ||
4c11d7ae | 544 | WARN_ON_ONCE(!irqs_disabled()); |
92205c23 | 545 | __raw_spin_lock(&ftrace_max_lock); |
ab46428c | 546 | for_each_tracing_cpu(i) |
bc0c38d1 SR |
547 | tracing_reset(max_tr.data[i]); |
548 | ||
c7aafc54 | 549 | flip_trace(max_tr.data[cpu], data); |
89b2f978 | 550 | tracing_reset(data); |
bc0c38d1 SR |
551 | |
552 | __update_max_tr(tr, tsk, cpu); | |
92205c23 | 553 | __raw_spin_unlock(&ftrace_max_lock); |
bc0c38d1 SR |
554 | } |
555 | ||
4fcdae83 SR |
556 | /** |
557 | * register_tracer - register a tracer with the ftrace system. | |
558 | * @type - the plugin for the tracer | |
559 | * | |
560 | * Register a new plugin tracer. | |
561 | */ | |
bc0c38d1 SR |
562 | int register_tracer(struct tracer *type) |
563 | { | |
564 | struct tracer *t; | |
565 | int len; | |
566 | int ret = 0; | |
567 | ||
568 | if (!type->name) { | |
569 | pr_info("Tracer must have a name\n"); | |
570 | return -1; | |
571 | } | |
572 | ||
573 | mutex_lock(&trace_types_lock); | |
574 | for (t = trace_types; t; t = t->next) { | |
575 | if (strcmp(type->name, t->name) == 0) { | |
576 | /* already found */ | |
577 | pr_info("Trace %s already registered\n", | |
578 | type->name); | |
579 | ret = -1; | |
580 | goto out; | |
581 | } | |
582 | } | |
583 | ||
60a11774 SR |
584 | #ifdef CONFIG_FTRACE_STARTUP_TEST |
585 | if (type->selftest) { | |
586 | struct tracer *saved_tracer = current_trace; | |
587 | struct trace_array_cpu *data; | |
588 | struct trace_array *tr = &global_trace; | |
589 | int saved_ctrl = tr->ctrl; | |
590 | int i; | |
591 | /* | |
592 | * Run a selftest on this tracer. | |
593 | * Here we reset the trace buffer, and set the current | |
594 | * tracer to be this tracer. The tracer can then run some | |
595 | * internal tracing to verify that everything is in order. | |
596 | * If we fail, we do not register this tracer. | |
597 | */ | |
ab46428c | 598 | for_each_tracing_cpu(i) { |
60a11774 | 599 | data = tr->data[i]; |
c7aafc54 IM |
600 | if (!head_page(data)) |
601 | continue; | |
60a11774 SR |
602 | tracing_reset(data); |
603 | } | |
604 | current_trace = type; | |
605 | tr->ctrl = 0; | |
606 | /* the test is responsible for initializing and enabling */ | |
607 | pr_info("Testing tracer %s: ", type->name); | |
608 | ret = type->selftest(type, tr); | |
609 | /* the test is responsible for resetting too */ | |
610 | current_trace = saved_tracer; | |
611 | tr->ctrl = saved_ctrl; | |
612 | if (ret) { | |
613 | printk(KERN_CONT "FAILED!\n"); | |
614 | goto out; | |
615 | } | |
1d4db00a | 616 | /* Only reset on passing, to avoid touching corrupted buffers */ |
ab46428c | 617 | for_each_tracing_cpu(i) { |
1d4db00a SR |
618 | data = tr->data[i]; |
619 | if (!head_page(data)) | |
620 | continue; | |
621 | tracing_reset(data); | |
622 | } | |
60a11774 SR |
623 | printk(KERN_CONT "PASSED\n"); |
624 | } | |
625 | #endif | |
626 | ||
bc0c38d1 SR |
627 | type->next = trace_types; |
628 | trace_types = type; | |
629 | len = strlen(type->name); | |
630 | if (len > max_tracer_type_len) | |
631 | max_tracer_type_len = len; | |
60a11774 | 632 | |
bc0c38d1 SR |
633 | out: |
634 | mutex_unlock(&trace_types_lock); | |
635 | ||
636 | return ret; | |
637 | } | |
638 | ||
639 | void unregister_tracer(struct tracer *type) | |
640 | { | |
641 | struct tracer **t; | |
642 | int len; | |
643 | ||
644 | mutex_lock(&trace_types_lock); | |
645 | for (t = &trace_types; *t; t = &(*t)->next) { | |
646 | if (*t == type) | |
647 | goto found; | |
648 | } | |
649 | pr_info("Trace %s not registered\n", type->name); | |
650 | goto out; | |
651 | ||
652 | found: | |
653 | *t = (*t)->next; | |
654 | if (strlen(type->name) != max_tracer_type_len) | |
655 | goto out; | |
656 | ||
657 | max_tracer_type_len = 0; | |
658 | for (t = &trace_types; *t; t = &(*t)->next) { | |
659 | len = strlen((*t)->name); | |
660 | if (len > max_tracer_type_len) | |
661 | max_tracer_type_len = len; | |
662 | } | |
663 | out: | |
664 | mutex_unlock(&trace_types_lock); | |
665 | } | |
666 | ||
e309b41d | 667 | void tracing_reset(struct trace_array_cpu *data) |
bc0c38d1 SR |
668 | { |
669 | data->trace_idx = 0; | |
53d0aa77 | 670 | data->overrun = 0; |
93a588f4 SR |
671 | data->trace_head = data->trace_tail = head_page(data); |
672 | data->trace_head_idx = 0; | |
673 | data->trace_tail_idx = 0; | |
bc0c38d1 SR |
674 | } |
675 | ||
bc0c38d1 SR |
676 | #define SAVED_CMDLINES 128 |
677 | static unsigned map_pid_to_cmdline[PID_MAX_DEFAULT+1]; | |
678 | static unsigned map_cmdline_to_pid[SAVED_CMDLINES]; | |
679 | static char saved_cmdlines[SAVED_CMDLINES][TASK_COMM_LEN]; | |
680 | static int cmdline_idx; | |
681 | static DEFINE_SPINLOCK(trace_cmdline_lock); | |
25b0b44a | 682 | |
25b0b44a SR |
683 | /* temporary disable recording */ |
684 | atomic_t trace_record_cmdline_disabled __read_mostly; | |
bc0c38d1 SR |
685 | |
686 | static void trace_init_cmdlines(void) | |
687 | { | |
688 | memset(&map_pid_to_cmdline, -1, sizeof(map_pid_to_cmdline)); | |
689 | memset(&map_cmdline_to_pid, -1, sizeof(map_cmdline_to_pid)); | |
690 | cmdline_idx = 0; | |
691 | } | |
692 | ||
e309b41d | 693 | void trace_stop_cmdline_recording(void); |
bc0c38d1 | 694 | |
e309b41d | 695 | static void trace_save_cmdline(struct task_struct *tsk) |
bc0c38d1 SR |
696 | { |
697 | unsigned map; | |
698 | unsigned idx; | |
699 | ||
700 | if (!tsk->pid || unlikely(tsk->pid > PID_MAX_DEFAULT)) | |
701 | return; | |
702 | ||
703 | /* | |
704 | * It's not the end of the world if we don't get | |
705 | * the lock, but we also don't want to spin | |
706 | * nor do we want to disable interrupts, | |
707 | * so if we miss here, then better luck next time. | |
708 | */ | |
709 | if (!spin_trylock(&trace_cmdline_lock)) | |
710 | return; | |
711 | ||
712 | idx = map_pid_to_cmdline[tsk->pid]; | |
713 | if (idx >= SAVED_CMDLINES) { | |
714 | idx = (cmdline_idx + 1) % SAVED_CMDLINES; | |
715 | ||
716 | map = map_cmdline_to_pid[idx]; | |
717 | if (map <= PID_MAX_DEFAULT) | |
718 | map_pid_to_cmdline[map] = (unsigned)-1; | |
719 | ||
720 | map_pid_to_cmdline[tsk->pid] = idx; | |
721 | ||
722 | cmdline_idx = idx; | |
723 | } | |
724 | ||
725 | memcpy(&saved_cmdlines[idx], tsk->comm, TASK_COMM_LEN); | |
726 | ||
727 | spin_unlock(&trace_cmdline_lock); | |
728 | } | |
729 | ||
e309b41d | 730 | static char *trace_find_cmdline(int pid) |
bc0c38d1 SR |
731 | { |
732 | char *cmdline = "<...>"; | |
733 | unsigned map; | |
734 | ||
735 | if (!pid) | |
736 | return "<idle>"; | |
737 | ||
738 | if (pid > PID_MAX_DEFAULT) | |
739 | goto out; | |
740 | ||
741 | map = map_pid_to_cmdline[pid]; | |
742 | if (map >= SAVED_CMDLINES) | |
743 | goto out; | |
744 | ||
745 | cmdline = saved_cmdlines[map]; | |
746 | ||
747 | out: | |
748 | return cmdline; | |
749 | } | |
750 | ||
e309b41d | 751 | void tracing_record_cmdline(struct task_struct *tsk) |
bc0c38d1 SR |
752 | { |
753 | if (atomic_read(&trace_record_cmdline_disabled)) | |
754 | return; | |
755 | ||
756 | trace_save_cmdline(tsk); | |
757 | } | |
758 | ||
e309b41d | 759 | static inline struct list_head * |
93a588f4 SR |
760 | trace_next_list(struct trace_array_cpu *data, struct list_head *next) |
761 | { | |
762 | /* | |
763 | * Roundrobin - but skip the head (which is not a real page): | |
764 | */ | |
765 | next = next->next; | |
766 | if (unlikely(next == &data->trace_pages)) | |
767 | next = next->next; | |
768 | BUG_ON(next == &data->trace_pages); | |
769 | ||
770 | return next; | |
771 | } | |
772 | ||
e309b41d | 773 | static inline void * |
93a588f4 SR |
774 | trace_next_page(struct trace_array_cpu *data, void *addr) |
775 | { | |
776 | struct list_head *next; | |
777 | struct page *page; | |
778 | ||
779 | page = virt_to_page(addr); | |
780 | ||
781 | next = trace_next_list(data, &page->lru); | |
782 | page = list_entry(next, struct page, lru); | |
783 | ||
784 | return page_address(page); | |
785 | } | |
786 | ||
e309b41d | 787 | static inline struct trace_entry * |
c7aafc54 | 788 | tracing_get_trace_entry(struct trace_array *tr, struct trace_array_cpu *data) |
bc0c38d1 SR |
789 | { |
790 | unsigned long idx, idx_next; | |
791 | struct trace_entry *entry; | |
792 | ||
4c11d7ae | 793 | data->trace_idx++; |
93a588f4 | 794 | idx = data->trace_head_idx; |
bc0c38d1 SR |
795 | idx_next = idx + 1; |
796 | ||
c7aafc54 IM |
797 | BUG_ON(idx * TRACE_ENTRY_SIZE >= PAGE_SIZE); |
798 | ||
93a588f4 | 799 | entry = data->trace_head + idx * TRACE_ENTRY_SIZE; |
4c11d7ae SR |
800 | |
801 | if (unlikely(idx_next >= ENTRIES_PER_PAGE)) { | |
93a588f4 | 802 | data->trace_head = trace_next_page(data, data->trace_head); |
bc0c38d1 SR |
803 | idx_next = 0; |
804 | } | |
805 | ||
93a588f4 SR |
806 | if (data->trace_head == data->trace_tail && |
807 | idx_next == data->trace_tail_idx) { | |
808 | /* overrun */ | |
53d0aa77 | 809 | data->overrun++; |
93a588f4 SR |
810 | data->trace_tail_idx++; |
811 | if (data->trace_tail_idx >= ENTRIES_PER_PAGE) { | |
812 | data->trace_tail = | |
813 | trace_next_page(data, data->trace_tail); | |
814 | data->trace_tail_idx = 0; | |
815 | } | |
816 | } | |
817 | ||
818 | data->trace_head_idx = idx_next; | |
bc0c38d1 SR |
819 | |
820 | return entry; | |
821 | } | |
822 | ||
e309b41d | 823 | static inline void |
c7aafc54 | 824 | tracing_generic_entry_update(struct trace_entry *entry, unsigned long flags) |
bc0c38d1 SR |
825 | { |
826 | struct task_struct *tsk = current; | |
827 | unsigned long pc; | |
828 | ||
829 | pc = preempt_count(); | |
830 | ||
2e2ca155 SR |
831 | entry->field.preempt_count = pc & 0xff; |
832 | entry->field.pid = (tsk) ? tsk->pid : 0; | |
833 | entry->field.t = ftrace_now(raw_smp_processor_id()); | |
834 | entry->field.flags = | |
835 | (irqs_disabled_flags(flags) ? TRACE_FLAG_IRQS_OFF : 0) | | |
bc0c38d1 SR |
836 | ((pc & HARDIRQ_MASK) ? TRACE_FLAG_HARDIRQ : 0) | |
837 | ((pc & SOFTIRQ_MASK) ? TRACE_FLAG_SOFTIRQ : 0) | | |
838 | (need_resched() ? TRACE_FLAG_NEED_RESCHED : 0); | |
839 | } | |
840 | ||
e309b41d | 841 | void |
6fb44b71 SR |
842 | trace_function(struct trace_array *tr, struct trace_array_cpu *data, |
843 | unsigned long ip, unsigned long parent_ip, unsigned long flags) | |
bc0c38d1 SR |
844 | { |
845 | struct trace_entry *entry; | |
dcb6308f | 846 | unsigned long irq_flags; |
bc0c38d1 | 847 | |
92205c23 SR |
848 | raw_local_irq_save(irq_flags); |
849 | __raw_spin_lock(&data->lock); | |
2e2ca155 | 850 | entry = tracing_get_trace_entry(tr, data); |
bc0c38d1 | 851 | tracing_generic_entry_update(entry, flags); |
2e2ca155 SR |
852 | entry->type = TRACE_FN; |
853 | entry->field.fn.ip = ip; | |
854 | entry->field.fn.parent_ip = parent_ip; | |
92205c23 SR |
855 | __raw_spin_unlock(&data->lock); |
856 | raw_local_irq_restore(irq_flags); | |
bc0c38d1 SR |
857 | } |
858 | ||
e309b41d | 859 | void |
2e0f5761 IM |
860 | ftrace(struct trace_array *tr, struct trace_array_cpu *data, |
861 | unsigned long ip, unsigned long parent_ip, unsigned long flags) | |
862 | { | |
863 | if (likely(!atomic_read(&data->disabled))) | |
6fb44b71 | 864 | trace_function(tr, data, ip, parent_ip, flags); |
2e0f5761 IM |
865 | } |
866 | ||
bd8ac686 PP |
867 | #ifdef CONFIG_MMIOTRACE |
868 | void __trace_mmiotrace_rw(struct trace_array *tr, struct trace_array_cpu *data, | |
869 | struct mmiotrace_rw *rw) | |
870 | { | |
871 | struct trace_entry *entry; | |
872 | unsigned long irq_flags; | |
873 | ||
801a175b IM |
874 | raw_local_irq_save(irq_flags); |
875 | __raw_spin_lock(&data->lock); | |
876 | ||
2e2ca155 | 877 | entry = tracing_get_trace_entry(tr, data); |
bd8ac686 | 878 | tracing_generic_entry_update(entry, 0); |
2e2ca155 SR |
879 | entry->type = TRACE_MMIO_RW; |
880 | entry->field.mmiorw = *rw; | |
801a175b IM |
881 | |
882 | __raw_spin_unlock(&data->lock); | |
883 | raw_local_irq_restore(irq_flags); | |
bd8ac686 PP |
884 | |
885 | trace_wake_up(); | |
886 | } | |
887 | ||
888 | void __trace_mmiotrace_map(struct trace_array *tr, struct trace_array_cpu *data, | |
889 | struct mmiotrace_map *map) | |
890 | { | |
891 | struct trace_entry *entry; | |
892 | unsigned long irq_flags; | |
893 | ||
801a175b IM |
894 | raw_local_irq_save(irq_flags); |
895 | __raw_spin_lock(&data->lock); | |
896 | ||
2e2ca155 | 897 | entry = tracing_get_trace_entry(tr, data); |
bd8ac686 | 898 | tracing_generic_entry_update(entry, 0); |
2e2ca155 SR |
899 | entry->type = TRACE_MMIO_MAP; |
900 | entry->field.mmiomap = *map; | |
801a175b IM |
901 | |
902 | __raw_spin_unlock(&data->lock); | |
903 | raw_local_irq_restore(irq_flags); | |
bd8ac686 PP |
904 | |
905 | trace_wake_up(); | |
906 | } | |
907 | #endif | |
908 | ||
86387f7e IM |
909 | void __trace_stack(struct trace_array *tr, |
910 | struct trace_array_cpu *data, | |
911 | unsigned long flags, | |
912 | int skip) | |
913 | { | |
914 | struct trace_entry *entry; | |
915 | struct stack_trace trace; | |
916 | ||
917 | if (!(trace_flags & TRACE_ITER_STACKTRACE)) | |
918 | return; | |
919 | ||
920 | entry = tracing_get_trace_entry(tr, data); | |
921 | tracing_generic_entry_update(entry, flags); | |
922 | entry->type = TRACE_STACK; | |
923 | ||
2e2ca155 | 924 | memset(&entry->field.stack, 0, sizeof(entry->field.stack)); |
86387f7e IM |
925 | |
926 | trace.nr_entries = 0; | |
927 | trace.max_entries = FTRACE_STACK_ENTRIES; | |
928 | trace.skip = skip; | |
2e2ca155 | 929 | trace.entries = entry->field.stack.caller; |
86387f7e IM |
930 | |
931 | save_stack_trace(&trace); | |
f0a920d5 IM |
932 | } |
933 | ||
a4feb834 IM |
934 | void |
935 | __trace_special(void *__tr, void *__data, | |
936 | unsigned long arg1, unsigned long arg2, unsigned long arg3) | |
937 | { | |
938 | struct trace_array_cpu *data = __data; | |
939 | struct trace_array *tr = __tr; | |
940 | struct trace_entry *entry; | |
941 | unsigned long irq_flags; | |
942 | ||
943 | raw_local_irq_save(irq_flags); | |
944 | __raw_spin_lock(&data->lock); | |
2e2ca155 | 945 | entry = tracing_get_trace_entry(tr, data); |
a4feb834 | 946 | tracing_generic_entry_update(entry, 0); |
2e2ca155 SR |
947 | entry->type = TRACE_SPECIAL; |
948 | entry->field.special.arg1 = arg1; | |
949 | entry->field.special.arg2 = arg2; | |
950 | entry->field.special.arg3 = arg3; | |
a4feb834 IM |
951 | __trace_stack(tr, data, irq_flags, 4); |
952 | __raw_spin_unlock(&data->lock); | |
953 | raw_local_irq_restore(irq_flags); | |
954 | ||
955 | trace_wake_up(); | |
956 | } | |
957 | ||
e309b41d | 958 | void |
bc0c38d1 SR |
959 | tracing_sched_switch_trace(struct trace_array *tr, |
960 | struct trace_array_cpu *data, | |
86387f7e IM |
961 | struct task_struct *prev, |
962 | struct task_struct *next, | |
bc0c38d1 SR |
963 | unsigned long flags) |
964 | { | |
965 | struct trace_entry *entry; | |
dcb6308f | 966 | unsigned long irq_flags; |
bc0c38d1 | 967 | |
92205c23 SR |
968 | raw_local_irq_save(irq_flags); |
969 | __raw_spin_lock(&data->lock); | |
2e2ca155 | 970 | entry = tracing_get_trace_entry(tr, data); |
bc0c38d1 | 971 | tracing_generic_entry_update(entry, flags); |
2e2ca155 SR |
972 | entry->type = TRACE_CTX; |
973 | entry->field.ctx.prev_pid = prev->pid; | |
974 | entry->field.ctx.prev_prio = prev->prio; | |
975 | entry->field.ctx.prev_state = prev->state; | |
976 | entry->field.ctx.next_pid = next->pid; | |
977 | entry->field.ctx.next_prio = next->prio; | |
978 | entry->field.ctx.next_state = next->state; | |
74f4e369 | 979 | __trace_stack(tr, data, flags, 5); |
92205c23 SR |
980 | __raw_spin_unlock(&data->lock); |
981 | raw_local_irq_restore(irq_flags); | |
bc0c38d1 SR |
982 | } |
983 | ||
57422797 IM |
984 | void |
985 | tracing_sched_wakeup_trace(struct trace_array *tr, | |
986 | struct trace_array_cpu *data, | |
86387f7e IM |
987 | struct task_struct *wakee, |
988 | struct task_struct *curr, | |
57422797 IM |
989 | unsigned long flags) |
990 | { | |
991 | struct trace_entry *entry; | |
992 | unsigned long irq_flags; | |
993 | ||
92205c23 SR |
994 | raw_local_irq_save(irq_flags); |
995 | __raw_spin_lock(&data->lock); | |
57422797 IM |
996 | entry = tracing_get_trace_entry(tr, data); |
997 | tracing_generic_entry_update(entry, flags); | |
998 | entry->type = TRACE_WAKE; | |
2e2ca155 SR |
999 | entry->field.ctx.prev_pid = curr->pid; |
1000 | entry->field.ctx.prev_prio = curr->prio; | |
1001 | entry->field.ctx.prev_state = curr->state; | |
1002 | entry->field.ctx.next_pid = wakee->pid; | |
1003 | entry->field.ctx.next_prio = wakee->prio; | |
1004 | entry->field.ctx.next_state = wakee->state; | |
74f4e369 | 1005 | __trace_stack(tr, data, flags, 6); |
92205c23 SR |
1006 | __raw_spin_unlock(&data->lock); |
1007 | raw_local_irq_restore(irq_flags); | |
017730c1 IM |
1008 | |
1009 | trace_wake_up(); | |
57422797 IM |
1010 | } |
1011 | ||
4902f884 SR |
1012 | void |
1013 | ftrace_special(unsigned long arg1, unsigned long arg2, unsigned long arg3) | |
1014 | { | |
1015 | struct trace_array *tr = &global_trace; | |
1016 | struct trace_array_cpu *data; | |
1017 | unsigned long flags; | |
1018 | long disabled; | |
1019 | int cpu; | |
1020 | ||
1021 | if (tracing_disabled || current_trace == &no_tracer || !tr->ctrl) | |
1022 | return; | |
1023 | ||
1024 | local_irq_save(flags); | |
1025 | cpu = raw_smp_processor_id(); | |
1026 | data = tr->data[cpu]; | |
1027 | disabled = atomic_inc_return(&data->disabled); | |
1028 | ||
1029 | if (likely(disabled == 1)) | |
1030 | __trace_special(tr, data, arg1, arg2, arg3); | |
1031 | ||
1032 | atomic_dec(&data->disabled); | |
1033 | local_irq_restore(flags); | |
1034 | } | |
1035 | ||
2e0f5761 | 1036 | #ifdef CONFIG_FTRACE |
e309b41d | 1037 | static void |
2e0f5761 IM |
1038 | function_trace_call(unsigned long ip, unsigned long parent_ip) |
1039 | { | |
1040 | struct trace_array *tr = &global_trace; | |
1041 | struct trace_array_cpu *data; | |
1042 | unsigned long flags; | |
1043 | long disabled; | |
1044 | int cpu; | |
1045 | ||
60bc0800 | 1046 | if (unlikely(!ftrace_function_enabled)) |
2e0f5761 IM |
1047 | return; |
1048 | ||
ecea656d AS |
1049 | if (skip_trace(ip)) |
1050 | return; | |
1051 | ||
2e0f5761 IM |
1052 | local_irq_save(flags); |
1053 | cpu = raw_smp_processor_id(); | |
1054 | data = tr->data[cpu]; | |
1055 | disabled = atomic_inc_return(&data->disabled); | |
1056 | ||
1057 | if (likely(disabled == 1)) | |
6fb44b71 | 1058 | trace_function(tr, data, ip, parent_ip, flags); |
2e0f5761 IM |
1059 | |
1060 | atomic_dec(&data->disabled); | |
1061 | local_irq_restore(flags); | |
1062 | } | |
1063 | ||
1064 | static struct ftrace_ops trace_ops __read_mostly = | |
1065 | { | |
1066 | .func = function_trace_call, | |
1067 | }; | |
1068 | ||
e309b41d | 1069 | void tracing_start_function_trace(void) |
2e0f5761 | 1070 | { |
60bc0800 | 1071 | ftrace_function_enabled = 0; |
2e0f5761 | 1072 | register_ftrace_function(&trace_ops); |
60bc0800 SR |
1073 | if (tracer_enabled) |
1074 | ftrace_function_enabled = 1; | |
2e0f5761 IM |
1075 | } |
1076 | ||
e309b41d | 1077 | void tracing_stop_function_trace(void) |
2e0f5761 | 1078 | { |
60bc0800 | 1079 | ftrace_function_enabled = 0; |
2e0f5761 IM |
1080 | unregister_ftrace_function(&trace_ops); |
1081 | } | |
1082 | #endif | |
1083 | ||
bc0c38d1 SR |
1084 | enum trace_file_type { |
1085 | TRACE_FILE_LAT_FMT = 1, | |
1086 | }; | |
1087 | ||
dd0e545f | 1088 | /* Return the current entry. */ |
bc0c38d1 | 1089 | static struct trace_entry * |
4c11d7ae SR |
1090 | trace_entry_idx(struct trace_array *tr, struct trace_array_cpu *data, |
1091 | struct trace_iterator *iter, int cpu) | |
bc0c38d1 | 1092 | { |
4c11d7ae SR |
1093 | struct page *page; |
1094 | struct trace_entry *array; | |
bc0c38d1 | 1095 | |
4c11d7ae | 1096 | if (iter->next_idx[cpu] >= tr->entries || |
b3806b43 SR |
1097 | iter->next_idx[cpu] >= data->trace_idx || |
1098 | (data->trace_head == data->trace_tail && | |
1099 | data->trace_head_idx == data->trace_tail_idx)) | |
bc0c38d1 SR |
1100 | return NULL; |
1101 | ||
4c11d7ae | 1102 | if (!iter->next_page[cpu]) { |
93a588f4 SR |
1103 | /* Initialize the iterator for this cpu trace buffer */ |
1104 | WARN_ON(!data->trace_tail); | |
1105 | page = virt_to_page(data->trace_tail); | |
1106 | iter->next_page[cpu] = &page->lru; | |
1107 | iter->next_page_idx[cpu] = data->trace_tail_idx; | |
4c11d7ae | 1108 | } |
bc0c38d1 | 1109 | |
4c11d7ae | 1110 | page = list_entry(iter->next_page[cpu], struct page, lru); |
c7aafc54 IM |
1111 | BUG_ON(&data->trace_pages == &page->lru); |
1112 | ||
4c11d7ae SR |
1113 | array = page_address(page); |
1114 | ||
93a588f4 | 1115 | WARN_ON(iter->next_page_idx[cpu] >= ENTRIES_PER_PAGE); |
4c11d7ae | 1116 | return &array[iter->next_page_idx[cpu]]; |
bc0c38d1 SR |
1117 | } |
1118 | ||
dd0e545f | 1119 | /* Increment the index counter of an iterator by one */ |
5a90f577 | 1120 | static void __trace_iterator_increment(struct trace_iterator *iter, int cpu) |
dd0e545f | 1121 | { |
dd0e545f SR |
1122 | iter->next_idx[cpu]++; |
1123 | iter->next_page_idx[cpu]++; | |
1124 | ||
1125 | if (iter->next_page_idx[cpu] >= ENTRIES_PER_PAGE) { | |
1126 | struct trace_array_cpu *data = iter->tr->data[cpu]; | |
1127 | ||
1128 | iter->next_page_idx[cpu] = 0; | |
1129 | iter->next_page[cpu] = | |
1130 | trace_next_list(data, iter->next_page[cpu]); | |
1131 | } | |
1132 | } | |
1133 | ||
5a90f577 SR |
1134 | static void trace_iterator_increment(struct trace_iterator *iter, int cpu) |
1135 | { | |
1136 | iter->idx++; | |
1137 | __trace_iterator_increment(iter, cpu); | |
1138 | } | |
1139 | ||
e309b41d | 1140 | static struct trace_entry * |
dd0e545f SR |
1141 | trace_entry_next(struct trace_array *tr, struct trace_array_cpu *data, |
1142 | struct trace_iterator *iter, int cpu) | |
1143 | { | |
1144 | struct list_head *next_page; | |
1145 | struct trace_entry *ent; | |
1146 | int idx, next_idx, next_page_idx; | |
1147 | ||
1148 | ent = trace_entry_idx(tr, tr->data[cpu], iter, cpu); | |
1149 | ||
1150 | if (likely(!ent || ent->type != TRACE_CONT)) | |
1151 | return ent; | |
1152 | ||
1153 | /* save the iterator details */ | |
1154 | idx = iter->idx; | |
1155 | next_idx = iter->next_idx[cpu]; | |
1156 | next_page_idx = iter->next_page_idx[cpu]; | |
1157 | next_page = iter->next_page[cpu]; | |
1158 | ||
1159 | /* find a real entry */ | |
1160 | do { | |
5a90f577 | 1161 | __trace_iterator_increment(iter, cpu); |
dd0e545f SR |
1162 | ent = trace_entry_idx(tr, tr->data[cpu], iter, cpu); |
1163 | } while (ent && ent->type != TRACE_CONT); | |
1164 | ||
1165 | /* reset the iterator */ | |
1166 | iter->idx = idx; | |
1167 | iter->next_idx[cpu] = next_idx; | |
1168 | iter->next_page_idx[cpu] = next_page_idx; | |
1169 | iter->next_page[cpu] = next_page; | |
1170 | ||
1171 | return ent; | |
1172 | } | |
1173 | ||
1174 | static struct trace_entry * | |
1175 | __find_next_entry(struct trace_iterator *iter, int *ent_cpu, int inc) | |
bc0c38d1 SR |
1176 | { |
1177 | struct trace_array *tr = iter->tr; | |
1178 | struct trace_entry *ent, *next = NULL; | |
1179 | int next_cpu = -1; | |
1180 | int cpu; | |
1181 | ||
ab46428c | 1182 | for_each_tracing_cpu(cpu) { |
c7aafc54 | 1183 | if (!head_page(tr->data[cpu])) |
bc0c38d1 | 1184 | continue; |
dd0e545f | 1185 | |
4c11d7ae | 1186 | ent = trace_entry_idx(tr, tr->data[cpu], iter, cpu); |
dd0e545f SR |
1187 | |
1188 | if (ent && ent->type == TRACE_CONT) { | |
1189 | struct trace_array_cpu *data = tr->data[cpu]; | |
1190 | ||
1191 | if (!inc) | |
1192 | ent = trace_entry_next(tr, data, iter, cpu); | |
1193 | else { | |
1194 | while (ent && ent->type == TRACE_CONT) { | |
5a90f577 | 1195 | __trace_iterator_increment(iter, cpu); |
dd0e545f SR |
1196 | ent = trace_entry_idx(tr, tr->data[cpu], |
1197 | iter, cpu); | |
1198 | } | |
1199 | } | |
1200 | } | |
1201 | ||
cdd31cd2 IM |
1202 | /* |
1203 | * Pick the entry with the smallest timestamp: | |
1204 | */ | |
2e2ca155 | 1205 | if (ent && (!next || ent->field.t < next->field.t)) { |
bc0c38d1 SR |
1206 | next = ent; |
1207 | next_cpu = cpu; | |
1208 | } | |
1209 | } | |
1210 | ||
1211 | if (ent_cpu) | |
1212 | *ent_cpu = next_cpu; | |
1213 | ||
1214 | return next; | |
1215 | } | |
1216 | ||
dd0e545f SR |
1217 | /* Find the next real entry, without updating the iterator itself */ |
1218 | static struct trace_entry * | |
1219 | find_next_entry(struct trace_iterator *iter, int *ent_cpu) | |
bc0c38d1 | 1220 | { |
dd0e545f SR |
1221 | return __find_next_entry(iter, ent_cpu, 0); |
1222 | } | |
1223 | ||
1224 | /* Find the next real entry, and increment the iterator to the next entry */ | |
1225 | static void *find_next_entry_inc(struct trace_iterator *iter) | |
1226 | { | |
1227 | struct trace_entry *next; | |
1228 | int next_cpu = -1; | |
8c523a9d | 1229 | |
dd0e545f | 1230 | next = __find_next_entry(iter, &next_cpu, 1); |
bc0c38d1 | 1231 | |
dd0e545f SR |
1232 | iter->prev_ent = iter->ent; |
1233 | iter->prev_cpu = iter->cpu; | |
1234 | ||
1235 | iter->ent = next; | |
1236 | iter->cpu = next_cpu; | |
1237 | ||
1238 | if (next) | |
1239 | trace_iterator_increment(iter, iter->cpu); | |
1240 | ||
1241 | return next ? iter : NULL; | |
b3806b43 | 1242 | } |
bc0c38d1 | 1243 | |
e309b41d | 1244 | static void trace_consume(struct trace_iterator *iter) |
b3806b43 SR |
1245 | { |
1246 | struct trace_array_cpu *data = iter->tr->data[iter->cpu]; | |
dd0e545f | 1247 | struct trace_entry *ent; |
b3806b43 | 1248 | |
dd0e545f | 1249 | again: |
b3806b43 SR |
1250 | data->trace_tail_idx++; |
1251 | if (data->trace_tail_idx >= ENTRIES_PER_PAGE) { | |
1252 | data->trace_tail = trace_next_page(data, data->trace_tail); | |
1253 | data->trace_tail_idx = 0; | |
1254 | } | |
4e3c3333 | 1255 | |
b3806b43 SR |
1256 | /* Check if we empty it, then reset the index */ |
1257 | if (data->trace_head == data->trace_tail && | |
1258 | data->trace_head_idx == data->trace_tail_idx) | |
1259 | data->trace_idx = 0; | |
b3806b43 | 1260 | |
dd0e545f SR |
1261 | ent = trace_entry_idx(iter->tr, iter->tr->data[iter->cpu], |
1262 | iter, iter->cpu); | |
1263 | if (ent && ent->type == TRACE_CONT) | |
1264 | goto again; | |
bc0c38d1 SR |
1265 | } |
1266 | ||
e309b41d | 1267 | static void *s_next(struct seq_file *m, void *v, loff_t *pos) |
bc0c38d1 SR |
1268 | { |
1269 | struct trace_iterator *iter = m->private; | |
bc0c38d1 | 1270 | int i = (int)*pos; |
4e3c3333 | 1271 | void *ent; |
bc0c38d1 SR |
1272 | |
1273 | (*pos)++; | |
1274 | ||
1275 | /* can't go backwards */ | |
1276 | if (iter->idx > i) | |
1277 | return NULL; | |
1278 | ||
1279 | if (iter->idx < 0) | |
1280 | ent = find_next_entry_inc(iter); | |
1281 | else | |
1282 | ent = iter; | |
1283 | ||
1284 | while (ent && iter->idx < i) | |
1285 | ent = find_next_entry_inc(iter); | |
1286 | ||
1287 | iter->pos = *pos; | |
1288 | ||
bc0c38d1 SR |
1289 | return ent; |
1290 | } | |
1291 | ||
1292 | static void *s_start(struct seq_file *m, loff_t *pos) | |
1293 | { | |
1294 | struct trace_iterator *iter = m->private; | |
1295 | void *p = NULL; | |
1296 | loff_t l = 0; | |
1297 | int i; | |
1298 | ||
1299 | mutex_lock(&trace_types_lock); | |
1300 | ||
d15f57f2 SR |
1301 | if (!current_trace || current_trace != iter->trace) { |
1302 | mutex_unlock(&trace_types_lock); | |
bc0c38d1 | 1303 | return NULL; |
d15f57f2 | 1304 | } |
bc0c38d1 SR |
1305 | |
1306 | atomic_inc(&trace_record_cmdline_disabled); | |
1307 | ||
1308 | /* let the tracer grab locks here if needed */ | |
1309 | if (current_trace->start) | |
1310 | current_trace->start(iter); | |
1311 | ||
1312 | if (*pos != iter->pos) { | |
1313 | iter->ent = NULL; | |
1314 | iter->cpu = 0; | |
1315 | iter->idx = -1; | |
4e3c3333 IM |
1316 | iter->prev_ent = NULL; |
1317 | iter->prev_cpu = -1; | |
bc0c38d1 | 1318 | |
ab46428c | 1319 | for_each_tracing_cpu(i) { |
bc0c38d1 | 1320 | iter->next_idx[i] = 0; |
4c11d7ae SR |
1321 | iter->next_page[i] = NULL; |
1322 | } | |
bc0c38d1 SR |
1323 | |
1324 | for (p = iter; p && l < *pos; p = s_next(m, p, &l)) | |
1325 | ; | |
1326 | ||
1327 | } else { | |
4c11d7ae | 1328 | l = *pos - 1; |
bc0c38d1 SR |
1329 | p = s_next(m, p, &l); |
1330 | } | |
1331 | ||
1332 | return p; | |
1333 | } | |
1334 | ||
1335 | static void s_stop(struct seq_file *m, void *p) | |
1336 | { | |
1337 | struct trace_iterator *iter = m->private; | |
1338 | ||
1339 | atomic_dec(&trace_record_cmdline_disabled); | |
1340 | ||
1341 | /* let the tracer release locks here if needed */ | |
1342 | if (current_trace && current_trace == iter->trace && iter->trace->stop) | |
1343 | iter->trace->stop(iter); | |
1344 | ||
1345 | mutex_unlock(&trace_types_lock); | |
1346 | } | |
1347 | ||
76094a2c AS |
1348 | #define KRETPROBE_MSG "[unknown/kretprobe'd]" |
1349 | ||
1350 | #ifdef CONFIG_KRETPROBES | |
1351 | static inline int kretprobed(unsigned long addr) | |
1352 | { | |
1353 | return addr == (unsigned long)kretprobe_trampoline; | |
1354 | } | |
1355 | #else | |
1356 | static inline int kretprobed(unsigned long addr) | |
1357 | { | |
1358 | return 0; | |
1359 | } | |
1360 | #endif /* CONFIG_KRETPROBES */ | |
1361 | ||
b3806b43 | 1362 | static int |
214023c3 | 1363 | seq_print_sym_short(struct trace_seq *s, const char *fmt, unsigned long address) |
bc0c38d1 SR |
1364 | { |
1365 | #ifdef CONFIG_KALLSYMS | |
1366 | char str[KSYM_SYMBOL_LEN]; | |
1367 | ||
1368 | kallsyms_lookup(address, NULL, NULL, NULL, str); | |
1369 | ||
b3806b43 | 1370 | return trace_seq_printf(s, fmt, str); |
bc0c38d1 | 1371 | #endif |
b3806b43 | 1372 | return 1; |
bc0c38d1 SR |
1373 | } |
1374 | ||
b3806b43 | 1375 | static int |
214023c3 SR |
1376 | seq_print_sym_offset(struct trace_seq *s, const char *fmt, |
1377 | unsigned long address) | |
bc0c38d1 SR |
1378 | { |
1379 | #ifdef CONFIG_KALLSYMS | |
1380 | char str[KSYM_SYMBOL_LEN]; | |
1381 | ||
1382 | sprint_symbol(str, address); | |
b3806b43 | 1383 | return trace_seq_printf(s, fmt, str); |
bc0c38d1 | 1384 | #endif |
b3806b43 | 1385 | return 1; |
bc0c38d1 SR |
1386 | } |
1387 | ||
1388 | #ifndef CONFIG_64BIT | |
1389 | # define IP_FMT "%08lx" | |
1390 | #else | |
1391 | # define IP_FMT "%016lx" | |
1392 | #endif | |
1393 | ||
e309b41d | 1394 | static int |
214023c3 | 1395 | seq_print_ip_sym(struct trace_seq *s, unsigned long ip, unsigned long sym_flags) |
bc0c38d1 | 1396 | { |
b3806b43 SR |
1397 | int ret; |
1398 | ||
1399 | if (!ip) | |
1400 | return trace_seq_printf(s, "0"); | |
bc0c38d1 SR |
1401 | |
1402 | if (sym_flags & TRACE_ITER_SYM_OFFSET) | |
b3806b43 | 1403 | ret = seq_print_sym_offset(s, "%s", ip); |
bc0c38d1 | 1404 | else |
b3806b43 SR |
1405 | ret = seq_print_sym_short(s, "%s", ip); |
1406 | ||
1407 | if (!ret) | |
1408 | return 0; | |
bc0c38d1 SR |
1409 | |
1410 | if (sym_flags & TRACE_ITER_SYM_ADDR) | |
b3806b43 SR |
1411 | ret = trace_seq_printf(s, " <" IP_FMT ">", ip); |
1412 | return ret; | |
bc0c38d1 SR |
1413 | } |
1414 | ||
e309b41d | 1415 | static void print_lat_help_header(struct seq_file *m) |
bc0c38d1 | 1416 | { |
a6168353 ME |
1417 | seq_puts(m, "# _------=> CPU# \n"); |
1418 | seq_puts(m, "# / _-----=> irqs-off \n"); | |
1419 | seq_puts(m, "# | / _----=> need-resched \n"); | |
1420 | seq_puts(m, "# || / _---=> hardirq/softirq \n"); | |
1421 | seq_puts(m, "# ||| / _--=> preempt-depth \n"); | |
1422 | seq_puts(m, "# |||| / \n"); | |
1423 | seq_puts(m, "# ||||| delay \n"); | |
1424 | seq_puts(m, "# cmd pid ||||| time | caller \n"); | |
1425 | seq_puts(m, "# \\ / ||||| \\ | / \n"); | |
bc0c38d1 SR |
1426 | } |
1427 | ||
e309b41d | 1428 | static void print_func_help_header(struct seq_file *m) |
bc0c38d1 | 1429 | { |
a6168353 ME |
1430 | seq_puts(m, "# TASK-PID CPU# TIMESTAMP FUNCTION\n"); |
1431 | seq_puts(m, "# | | | | |\n"); | |
bc0c38d1 SR |
1432 | } |
1433 | ||
1434 | ||
e309b41d | 1435 | static void |
bc0c38d1 SR |
1436 | print_trace_header(struct seq_file *m, struct trace_iterator *iter) |
1437 | { | |
1438 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); | |
1439 | struct trace_array *tr = iter->tr; | |
1440 | struct trace_array_cpu *data = tr->data[tr->cpu]; | |
1441 | struct tracer *type = current_trace; | |
4c11d7ae SR |
1442 | unsigned long total = 0; |
1443 | unsigned long entries = 0; | |
bc0c38d1 SR |
1444 | int cpu; |
1445 | const char *name = "preemption"; | |
1446 | ||
1447 | if (type) | |
1448 | name = type->name; | |
1449 | ||
ab46428c | 1450 | for_each_tracing_cpu(cpu) { |
c7aafc54 | 1451 | if (head_page(tr->data[cpu])) { |
4c11d7ae SR |
1452 | total += tr->data[cpu]->trace_idx; |
1453 | if (tr->data[cpu]->trace_idx > tr->entries) | |
bc0c38d1 | 1454 | entries += tr->entries; |
4c11d7ae | 1455 | else |
bc0c38d1 SR |
1456 | entries += tr->data[cpu]->trace_idx; |
1457 | } | |
1458 | } | |
1459 | ||
1460 | seq_printf(m, "%s latency trace v1.1.5 on %s\n", | |
1461 | name, UTS_RELEASE); | |
1462 | seq_puts(m, "-----------------------------------" | |
1463 | "---------------------------------\n"); | |
1464 | seq_printf(m, " latency: %lu us, #%lu/%lu, CPU#%d |" | |
1465 | " (M:%s VP:%d, KP:%d, SP:%d HP:%d", | |
57f50be1 | 1466 | nsecs_to_usecs(data->saved_latency), |
bc0c38d1 | 1467 | entries, |
4c11d7ae | 1468 | total, |
bc0c38d1 SR |
1469 | tr->cpu, |
1470 | #if defined(CONFIG_PREEMPT_NONE) | |
1471 | "server", | |
1472 | #elif defined(CONFIG_PREEMPT_VOLUNTARY) | |
1473 | "desktop", | |
b5c21b45 | 1474 | #elif defined(CONFIG_PREEMPT) |
bc0c38d1 SR |
1475 | "preempt", |
1476 | #else | |
1477 | "unknown", | |
1478 | #endif | |
1479 | /* These are reserved for later use */ | |
1480 | 0, 0, 0, 0); | |
1481 | #ifdef CONFIG_SMP | |
1482 | seq_printf(m, " #P:%d)\n", num_online_cpus()); | |
1483 | #else | |
1484 | seq_puts(m, ")\n"); | |
1485 | #endif | |
1486 | seq_puts(m, " -----------------\n"); | |
1487 | seq_printf(m, " | task: %.16s-%d " | |
1488 | "(uid:%d nice:%ld policy:%ld rt_prio:%ld)\n", | |
1489 | data->comm, data->pid, data->uid, data->nice, | |
1490 | data->policy, data->rt_priority); | |
1491 | seq_puts(m, " -----------------\n"); | |
1492 | ||
1493 | if (data->critical_start) { | |
1494 | seq_puts(m, " => started at: "); | |
214023c3 SR |
1495 | seq_print_ip_sym(&iter->seq, data->critical_start, sym_flags); |
1496 | trace_print_seq(m, &iter->seq); | |
bc0c38d1 | 1497 | seq_puts(m, "\n => ended at: "); |
214023c3 SR |
1498 | seq_print_ip_sym(&iter->seq, data->critical_end, sym_flags); |
1499 | trace_print_seq(m, &iter->seq); | |
bc0c38d1 SR |
1500 | seq_puts(m, "\n"); |
1501 | } | |
1502 | ||
1503 | seq_puts(m, "\n"); | |
1504 | } | |
1505 | ||
e309b41d | 1506 | static void |
214023c3 | 1507 | lat_print_generic(struct trace_seq *s, struct trace_entry *entry, int cpu) |
bc0c38d1 | 1508 | { |
2e2ca155 | 1509 | struct trace_field *field = &entry->field; |
bc0c38d1 SR |
1510 | int hardirq, softirq; |
1511 | char *comm; | |
1512 | ||
2e2ca155 | 1513 | comm = trace_find_cmdline(field->pid); |
bc0c38d1 | 1514 | |
2e2ca155 | 1515 | trace_seq_printf(s, "%8.8s-%-5d ", comm, field->pid); |
a6168353 | 1516 | trace_seq_printf(s, "%3d", cpu); |
214023c3 | 1517 | trace_seq_printf(s, "%c%c", |
2e2ca155 SR |
1518 | (field->flags & TRACE_FLAG_IRQS_OFF) ? 'd' : '.', |
1519 | ((field->flags & TRACE_FLAG_NEED_RESCHED) ? 'N' : '.')); | |
bc0c38d1 | 1520 | |
2e2ca155 SR |
1521 | hardirq = field->flags & TRACE_FLAG_HARDIRQ; |
1522 | softirq = field->flags & TRACE_FLAG_SOFTIRQ; | |
afc2abc0 | 1523 | if (hardirq && softirq) { |
214023c3 | 1524 | trace_seq_putc(s, 'H'); |
afc2abc0 IM |
1525 | } else { |
1526 | if (hardirq) { | |
214023c3 | 1527 | trace_seq_putc(s, 'h'); |
afc2abc0 | 1528 | } else { |
bc0c38d1 | 1529 | if (softirq) |
214023c3 | 1530 | trace_seq_putc(s, 's'); |
bc0c38d1 | 1531 | else |
214023c3 | 1532 | trace_seq_putc(s, '.'); |
bc0c38d1 SR |
1533 | } |
1534 | } | |
1535 | ||
2e2ca155 SR |
1536 | if (field->preempt_count) |
1537 | trace_seq_printf(s, "%x", field->preempt_count); | |
bc0c38d1 | 1538 | else |
214023c3 | 1539 | trace_seq_puts(s, "."); |
bc0c38d1 SR |
1540 | } |
1541 | ||
1542 | unsigned long preempt_mark_thresh = 100; | |
1543 | ||
e309b41d | 1544 | static void |
214023c3 | 1545 | lat_print_timestamp(struct trace_seq *s, unsigned long long abs_usecs, |
bc0c38d1 SR |
1546 | unsigned long rel_usecs) |
1547 | { | |
214023c3 | 1548 | trace_seq_printf(s, " %4lldus", abs_usecs); |
bc0c38d1 | 1549 | if (rel_usecs > preempt_mark_thresh) |
214023c3 | 1550 | trace_seq_puts(s, "!: "); |
bc0c38d1 | 1551 | else if (rel_usecs > 1) |
214023c3 | 1552 | trace_seq_puts(s, "+: "); |
bc0c38d1 | 1553 | else |
214023c3 | 1554 | trace_seq_puts(s, " : "); |
bc0c38d1 SR |
1555 | } |
1556 | ||
1557 | static const char state_to_char[] = TASK_STATE_TO_CHAR_STR; | |
1558 | ||
dd0e545f SR |
1559 | static void |
1560 | trace_seq_print_cont(struct trace_seq *s, struct trace_iterator *iter) | |
1561 | { | |
1562 | struct trace_array *tr = iter->tr; | |
1563 | struct trace_array_cpu *data = tr->data[iter->cpu]; | |
1564 | struct trace_entry *ent; | |
1565 | ||
1566 | ent = trace_entry_idx(tr, data, iter, iter->cpu); | |
1567 | if (!ent || ent->type != TRACE_CONT) { | |
1568 | trace_seq_putc(s, '\n'); | |
1569 | return; | |
1570 | } | |
1571 | ||
1572 | do { | |
1573 | trace_seq_printf(s, "%s", ent->cont.buf); | |
5a90f577 | 1574 | __trace_iterator_increment(iter, iter->cpu); |
dd0e545f SR |
1575 | ent = trace_entry_idx(tr, data, iter, iter->cpu); |
1576 | } while (ent && ent->type == TRACE_CONT); | |
1577 | } | |
1578 | ||
e309b41d | 1579 | static int |
214023c3 | 1580 | print_lat_fmt(struct trace_iterator *iter, unsigned int trace_idx, int cpu) |
bc0c38d1 | 1581 | { |
214023c3 | 1582 | struct trace_seq *s = &iter->seq; |
bc0c38d1 SR |
1583 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); |
1584 | struct trace_entry *next_entry = find_next_entry(iter, NULL); | |
1585 | unsigned long verbose = (trace_flags & TRACE_ITER_VERBOSE); | |
1586 | struct trace_entry *entry = iter->ent; | |
2e2ca155 | 1587 | struct trace_field *field = &entry->field; |
bc0c38d1 SR |
1588 | unsigned long abs_usecs; |
1589 | unsigned long rel_usecs; | |
1590 | char *comm; | |
bac524d3 | 1591 | int S, T; |
86387f7e | 1592 | int i; |
d17d9691 | 1593 | unsigned state; |
bc0c38d1 SR |
1594 | |
1595 | if (!next_entry) | |
1596 | next_entry = entry; | |
dd0e545f SR |
1597 | |
1598 | if (entry->type == TRACE_CONT) | |
1599 | return 1; | |
1600 | ||
2e2ca155 SR |
1601 | rel_usecs = ns2usecs(next_entry->field.t - entry->field.t); |
1602 | abs_usecs = ns2usecs(entry->field.t - iter->tr->time_start); | |
bc0c38d1 SR |
1603 | |
1604 | if (verbose) { | |
2e2ca155 | 1605 | comm = trace_find_cmdline(field->pid); |
a6168353 | 1606 | trace_seq_printf(s, "%16s %5d %3d %d %08x %08x [%08lx]" |
214023c3 SR |
1607 | " %ld.%03ldms (+%ld.%03ldms): ", |
1608 | comm, | |
2e2ca155 SR |
1609 | field->pid, cpu, field->flags, |
1610 | field->preempt_count, trace_idx, | |
1611 | ns2usecs(field->t), | |
214023c3 SR |
1612 | abs_usecs/1000, |
1613 | abs_usecs % 1000, rel_usecs/1000, | |
1614 | rel_usecs % 1000); | |
bc0c38d1 | 1615 | } else { |
f29c73fe IM |
1616 | lat_print_generic(s, entry, cpu); |
1617 | lat_print_timestamp(s, abs_usecs, rel_usecs); | |
bc0c38d1 SR |
1618 | } |
1619 | switch (entry->type) { | |
1620 | case TRACE_FN: | |
2e2ca155 | 1621 | seq_print_ip_sym(s, field->fn.ip, sym_flags); |
214023c3 | 1622 | trace_seq_puts(s, " ("); |
2e2ca155 | 1623 | if (kretprobed(field->fn.parent_ip)) |
76094a2c AS |
1624 | trace_seq_puts(s, KRETPROBE_MSG); |
1625 | else | |
2e2ca155 | 1626 | seq_print_ip_sym(s, field->fn.parent_ip, sym_flags); |
214023c3 | 1627 | trace_seq_puts(s, ")\n"); |
bc0c38d1 SR |
1628 | break; |
1629 | case TRACE_CTX: | |
57422797 | 1630 | case TRACE_WAKE: |
2e2ca155 SR |
1631 | T = field->ctx.next_state < sizeof(state_to_char) ? |
1632 | state_to_char[field->ctx.next_state] : 'X'; | |
bac524d3 | 1633 | |
2e2ca155 SR |
1634 | state = field->ctx.prev_state ? |
1635 | __ffs(field->ctx.prev_state) + 1 : 0; | |
d17d9691 | 1636 | S = state < sizeof(state_to_char) - 1 ? state_to_char[state] : 'X'; |
2e2ca155 | 1637 | comm = trace_find_cmdline(field->ctx.next_pid); |
bac524d3 | 1638 | trace_seq_printf(s, " %5d:%3d:%c %s %5d:%3d:%c %s\n", |
2e2ca155 SR |
1639 | field->ctx.prev_pid, |
1640 | field->ctx.prev_prio, | |
57422797 | 1641 | S, entry->type == TRACE_CTX ? "==>" : " +", |
2e2ca155 SR |
1642 | field->ctx.next_pid, |
1643 | field->ctx.next_prio, | |
bac524d3 | 1644 | T, comm); |
bc0c38d1 | 1645 | break; |
f0a920d5 | 1646 | case TRACE_SPECIAL: |
88a4216c | 1647 | trace_seq_printf(s, "# %ld %ld %ld\n", |
2e2ca155 SR |
1648 | field->special.arg1, |
1649 | field->special.arg2, | |
1650 | field->special.arg3); | |
f0a920d5 | 1651 | break; |
86387f7e IM |
1652 | case TRACE_STACK: |
1653 | for (i = 0; i < FTRACE_STACK_ENTRIES; i++) { | |
1654 | if (i) | |
1655 | trace_seq_puts(s, " <= "); | |
2e2ca155 | 1656 | seq_print_ip_sym(s, field->stack.caller[i], sym_flags); |
86387f7e IM |
1657 | } |
1658 | trace_seq_puts(s, "\n"); | |
1659 | break; | |
dd0e545f SR |
1660 | case TRACE_PRINT: |
1661 | seq_print_ip_sym(s, field->print.ip, sym_flags); | |
1662 | trace_seq_printf(s, ": %s", field->print.buf); | |
652567aa | 1663 | if (field->flags & TRACE_FLAG_CONT) |
dd0e545f SR |
1664 | trace_seq_print_cont(s, iter); |
1665 | break; | |
89b2f978 | 1666 | default: |
214023c3 | 1667 | trace_seq_printf(s, "Unknown type %d\n", entry->type); |
bc0c38d1 | 1668 | } |
f9896bf3 | 1669 | return 1; |
bc0c38d1 SR |
1670 | } |
1671 | ||
e309b41d | 1672 | static int print_trace_fmt(struct trace_iterator *iter) |
bc0c38d1 | 1673 | { |
214023c3 | 1674 | struct trace_seq *s = &iter->seq; |
bc0c38d1 | 1675 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); |
4e3c3333 | 1676 | struct trace_entry *entry; |
2e2ca155 | 1677 | struct trace_field *field; |
bc0c38d1 SR |
1678 | unsigned long usec_rem; |
1679 | unsigned long long t; | |
1680 | unsigned long secs; | |
1681 | char *comm; | |
b3806b43 | 1682 | int ret; |
bac524d3 | 1683 | int S, T; |
86387f7e | 1684 | int i; |
bc0c38d1 | 1685 | |
4e3c3333 | 1686 | entry = iter->ent; |
dd0e545f SR |
1687 | |
1688 | if (entry->type == TRACE_CONT) | |
1689 | return 1; | |
1690 | ||
2e2ca155 | 1691 | field = &entry->field; |
4e3c3333 | 1692 | |
2e2ca155 | 1693 | comm = trace_find_cmdline(iter->ent->field.pid); |
bc0c38d1 | 1694 | |
2e2ca155 | 1695 | t = ns2usecs(field->t); |
bc0c38d1 SR |
1696 | usec_rem = do_div(t, 1000000ULL); |
1697 | secs = (unsigned long)t; | |
1698 | ||
2e2ca155 | 1699 | ret = trace_seq_printf(s, "%16s-%-5d ", comm, field->pid); |
f29c73fe IM |
1700 | if (!ret) |
1701 | return 0; | |
a6168353 | 1702 | ret = trace_seq_printf(s, "[%03d] ", iter->cpu); |
f29c73fe IM |
1703 | if (!ret) |
1704 | return 0; | |
1705 | ret = trace_seq_printf(s, "%5lu.%06lu: ", secs, usec_rem); | |
1706 | if (!ret) | |
1707 | return 0; | |
bc0c38d1 SR |
1708 | |
1709 | switch (entry->type) { | |
1710 | case TRACE_FN: | |
2e2ca155 | 1711 | ret = seq_print_ip_sym(s, field->fn.ip, sym_flags); |
b3806b43 SR |
1712 | if (!ret) |
1713 | return 0; | |
bc0c38d1 | 1714 | if ((sym_flags & TRACE_ITER_PRINT_PARENT) && |
2e2ca155 | 1715 | field->fn.parent_ip) { |
b3806b43 SR |
1716 | ret = trace_seq_printf(s, " <-"); |
1717 | if (!ret) | |
1718 | return 0; | |
2e2ca155 | 1719 | if (kretprobed(field->fn.parent_ip)) |
76094a2c AS |
1720 | ret = trace_seq_puts(s, KRETPROBE_MSG); |
1721 | else | |
2e2ca155 SR |
1722 | ret = seq_print_ip_sym(s, |
1723 | field->fn.parent_ip, | |
76094a2c | 1724 | sym_flags); |
b3806b43 SR |
1725 | if (!ret) |
1726 | return 0; | |
bc0c38d1 | 1727 | } |
b3806b43 SR |
1728 | ret = trace_seq_printf(s, "\n"); |
1729 | if (!ret) | |
1730 | return 0; | |
bc0c38d1 SR |
1731 | break; |
1732 | case TRACE_CTX: | |
57422797 | 1733 | case TRACE_WAKE: |
2e2ca155 SR |
1734 | S = field->ctx.prev_state < sizeof(state_to_char) ? |
1735 | state_to_char[field->ctx.prev_state] : 'X'; | |
1736 | T = field->ctx.next_state < sizeof(state_to_char) ? | |
1737 | state_to_char[field->ctx.next_state] : 'X'; | |
bac524d3 | 1738 | ret = trace_seq_printf(s, " %5d:%3d:%c %s %5d:%3d:%c\n", |
2e2ca155 SR |
1739 | field->ctx.prev_pid, |
1740 | field->ctx.prev_prio, | |
b3806b43 | 1741 | S, |
57422797 | 1742 | entry->type == TRACE_CTX ? "==>" : " +", |
2e2ca155 SR |
1743 | field->ctx.next_pid, |
1744 | field->ctx.next_prio, | |
bac524d3 | 1745 | T); |
b3806b43 SR |
1746 | if (!ret) |
1747 | return 0; | |
bc0c38d1 | 1748 | break; |
f0a920d5 | 1749 | case TRACE_SPECIAL: |
88a4216c | 1750 | ret = trace_seq_printf(s, "# %ld %ld %ld\n", |
2e2ca155 SR |
1751 | field->special.arg1, |
1752 | field->special.arg2, | |
1753 | field->special.arg3); | |
f0a920d5 IM |
1754 | if (!ret) |
1755 | return 0; | |
1756 | break; | |
86387f7e IM |
1757 | case TRACE_STACK: |
1758 | for (i = 0; i < FTRACE_STACK_ENTRIES; i++) { | |
1759 | if (i) { | |
1760 | ret = trace_seq_puts(s, " <= "); | |
1761 | if (!ret) | |
1762 | return 0; | |
1763 | } | |
2e2ca155 | 1764 | ret = seq_print_ip_sym(s, field->stack.caller[i], |
86387f7e IM |
1765 | sym_flags); |
1766 | if (!ret) | |
1767 | return 0; | |
1768 | } | |
1769 | ret = trace_seq_puts(s, "\n"); | |
1770 | if (!ret) | |
1771 | return 0; | |
1772 | break; | |
dd0e545f SR |
1773 | case TRACE_PRINT: |
1774 | seq_print_ip_sym(s, field->print.ip, sym_flags); | |
1775 | trace_seq_printf(s, ": %s", field->print.buf); | |
652567aa | 1776 | if (field->flags & TRACE_FLAG_CONT) |
dd0e545f SR |
1777 | trace_seq_print_cont(s, iter); |
1778 | break; | |
bc0c38d1 | 1779 | } |
b3806b43 | 1780 | return 1; |
bc0c38d1 SR |
1781 | } |
1782 | ||
e309b41d | 1783 | static int print_raw_fmt(struct trace_iterator *iter) |
f9896bf3 IM |
1784 | { |
1785 | struct trace_seq *s = &iter->seq; | |
1786 | struct trace_entry *entry; | |
2e2ca155 | 1787 | struct trace_field *field; |
f9896bf3 | 1788 | int ret; |
bac524d3 | 1789 | int S, T; |
f9896bf3 IM |
1790 | |
1791 | entry = iter->ent; | |
dd0e545f SR |
1792 | |
1793 | if (entry->type == TRACE_CONT) | |
1794 | return 1; | |
1795 | ||
2e2ca155 | 1796 | field = &entry->field; |
f9896bf3 IM |
1797 | |
1798 | ret = trace_seq_printf(s, "%d %d %llu ", | |
2e2ca155 | 1799 | field->pid, iter->cpu, field->t); |
f9896bf3 IM |
1800 | if (!ret) |
1801 | return 0; | |
1802 | ||
1803 | switch (entry->type) { | |
1804 | case TRACE_FN: | |
1805 | ret = trace_seq_printf(s, "%x %x\n", | |
2e2ca155 SR |
1806 | field->fn.ip, |
1807 | field->fn.parent_ip); | |
f9896bf3 IM |
1808 | if (!ret) |
1809 | return 0; | |
1810 | break; | |
1811 | case TRACE_CTX: | |
57422797 | 1812 | case TRACE_WAKE: |
2e2ca155 SR |
1813 | S = field->ctx.prev_state < sizeof(state_to_char) ? |
1814 | state_to_char[field->ctx.prev_state] : 'X'; | |
1815 | T = field->ctx.next_state < sizeof(state_to_char) ? | |
1816 | state_to_char[field->ctx.next_state] : 'X'; | |
57422797 IM |
1817 | if (entry->type == TRACE_WAKE) |
1818 | S = '+'; | |
bac524d3 | 1819 | ret = trace_seq_printf(s, "%d %d %c %d %d %c\n", |
2e2ca155 SR |
1820 | field->ctx.prev_pid, |
1821 | field->ctx.prev_prio, | |
f9896bf3 | 1822 | S, |
2e2ca155 SR |
1823 | field->ctx.next_pid, |
1824 | field->ctx.next_prio, | |
bac524d3 | 1825 | T); |
f9896bf3 IM |
1826 | if (!ret) |
1827 | return 0; | |
1828 | break; | |
f0a920d5 | 1829 | case TRACE_SPECIAL: |
86387f7e | 1830 | case TRACE_STACK: |
88a4216c | 1831 | ret = trace_seq_printf(s, "# %ld %ld %ld\n", |
2e2ca155 SR |
1832 | field->special.arg1, |
1833 | field->special.arg2, | |
1834 | field->special.arg3); | |
f0a920d5 IM |
1835 | if (!ret) |
1836 | return 0; | |
1837 | break; | |
dd0e545f SR |
1838 | case TRACE_PRINT: |
1839 | trace_seq_printf(s, "# %lx %s", | |
1840 | field->print.ip, field->print.buf); | |
652567aa | 1841 | if (field->flags & TRACE_FLAG_CONT) |
dd0e545f SR |
1842 | trace_seq_print_cont(s, iter); |
1843 | break; | |
f9896bf3 IM |
1844 | } |
1845 | return 1; | |
1846 | } | |
1847 | ||
cb0f12aa IM |
1848 | #define SEQ_PUT_FIELD_RET(s, x) \ |
1849 | do { \ | |
1850 | if (!trace_seq_putmem(s, &(x), sizeof(x))) \ | |
1851 | return 0; \ | |
1852 | } while (0) | |
1853 | ||
5e3ca0ec IM |
1854 | #define SEQ_PUT_HEX_FIELD_RET(s, x) \ |
1855 | do { \ | |
1856 | if (!trace_seq_putmem_hex(s, &(x), sizeof(x))) \ | |
1857 | return 0; \ | |
1858 | } while (0) | |
1859 | ||
e309b41d | 1860 | static int print_hex_fmt(struct trace_iterator *iter) |
5e3ca0ec IM |
1861 | { |
1862 | struct trace_seq *s = &iter->seq; | |
1863 | unsigned char newline = '\n'; | |
1864 | struct trace_entry *entry; | |
2e2ca155 | 1865 | struct trace_field *field; |
bac524d3 | 1866 | int S, T; |
5e3ca0ec IM |
1867 | |
1868 | entry = iter->ent; | |
dd0e545f SR |
1869 | |
1870 | if (entry->type == TRACE_CONT) | |
1871 | return 1; | |
1872 | ||
2e2ca155 | 1873 | field = &entry->field; |
5e3ca0ec | 1874 | |
2e2ca155 | 1875 | SEQ_PUT_HEX_FIELD_RET(s, field->pid); |
5e3ca0ec | 1876 | SEQ_PUT_HEX_FIELD_RET(s, iter->cpu); |
2e2ca155 | 1877 | SEQ_PUT_HEX_FIELD_RET(s, field->t); |
5e3ca0ec IM |
1878 | |
1879 | switch (entry->type) { | |
1880 | case TRACE_FN: | |
2e2ca155 SR |
1881 | SEQ_PUT_HEX_FIELD_RET(s, field->fn.ip); |
1882 | SEQ_PUT_HEX_FIELD_RET(s, field->fn.parent_ip); | |
5e3ca0ec IM |
1883 | break; |
1884 | case TRACE_CTX: | |
57422797 | 1885 | case TRACE_WAKE: |
2e2ca155 SR |
1886 | S = field->ctx.prev_state < sizeof(state_to_char) ? |
1887 | state_to_char[field->ctx.prev_state] : 'X'; | |
1888 | T = field->ctx.next_state < sizeof(state_to_char) ? | |
1889 | state_to_char[field->ctx.next_state] : 'X'; | |
57422797 IM |
1890 | if (entry->type == TRACE_WAKE) |
1891 | S = '+'; | |
2e2ca155 SR |
1892 | SEQ_PUT_HEX_FIELD_RET(s, field->ctx.prev_pid); |
1893 | SEQ_PUT_HEX_FIELD_RET(s, field->ctx.prev_prio); | |
5e3ca0ec | 1894 | SEQ_PUT_HEX_FIELD_RET(s, S); |
2e2ca155 SR |
1895 | SEQ_PUT_HEX_FIELD_RET(s, field->ctx.next_pid); |
1896 | SEQ_PUT_HEX_FIELD_RET(s, field->ctx.next_prio); | |
bac524d3 | 1897 | SEQ_PUT_HEX_FIELD_RET(s, T); |
5e3ca0ec IM |
1898 | break; |
1899 | case TRACE_SPECIAL: | |
86387f7e | 1900 | case TRACE_STACK: |
2e2ca155 SR |
1901 | SEQ_PUT_HEX_FIELD_RET(s, field->special.arg1); |
1902 | SEQ_PUT_HEX_FIELD_RET(s, field->special.arg2); | |
1903 | SEQ_PUT_HEX_FIELD_RET(s, field->special.arg3); | |
5e3ca0ec IM |
1904 | break; |
1905 | } | |
1906 | SEQ_PUT_FIELD_RET(s, newline); | |
1907 | ||
1908 | return 1; | |
1909 | } | |
1910 | ||
e309b41d | 1911 | static int print_bin_fmt(struct trace_iterator *iter) |
cb0f12aa IM |
1912 | { |
1913 | struct trace_seq *s = &iter->seq; | |
1914 | struct trace_entry *entry; | |
2e2ca155 | 1915 | struct trace_field *field; |
cb0f12aa IM |
1916 | |
1917 | entry = iter->ent; | |
dd0e545f SR |
1918 | |
1919 | if (entry->type == TRACE_CONT) | |
1920 | return 1; | |
1921 | ||
2e2ca155 | 1922 | field = &entry->field; |
cb0f12aa | 1923 | |
2e2ca155 SR |
1924 | SEQ_PUT_FIELD_RET(s, field->pid); |
1925 | SEQ_PUT_FIELD_RET(s, field->cpu); | |
1926 | SEQ_PUT_FIELD_RET(s, field->t); | |
cb0f12aa IM |
1927 | |
1928 | switch (entry->type) { | |
1929 | case TRACE_FN: | |
2e2ca155 SR |
1930 | SEQ_PUT_FIELD_RET(s, field->fn.ip); |
1931 | SEQ_PUT_FIELD_RET(s, field->fn.parent_ip); | |
cb0f12aa IM |
1932 | break; |
1933 | case TRACE_CTX: | |
2e2ca155 SR |
1934 | SEQ_PUT_FIELD_RET(s, field->ctx.prev_pid); |
1935 | SEQ_PUT_FIELD_RET(s, field->ctx.prev_prio); | |
1936 | SEQ_PUT_FIELD_RET(s, field->ctx.prev_state); | |
1937 | SEQ_PUT_FIELD_RET(s, field->ctx.next_pid); | |
1938 | SEQ_PUT_FIELD_RET(s, field->ctx.next_prio); | |
1939 | SEQ_PUT_FIELD_RET(s, field->ctx.next_state); | |
cb0f12aa | 1940 | break; |
f0a920d5 | 1941 | case TRACE_SPECIAL: |
86387f7e | 1942 | case TRACE_STACK: |
2e2ca155 SR |
1943 | SEQ_PUT_FIELD_RET(s, field->special.arg1); |
1944 | SEQ_PUT_FIELD_RET(s, field->special.arg2); | |
1945 | SEQ_PUT_FIELD_RET(s, field->special.arg3); | |
f0a920d5 | 1946 | break; |
cb0f12aa IM |
1947 | } |
1948 | return 1; | |
1949 | } | |
1950 | ||
bc0c38d1 SR |
1951 | static int trace_empty(struct trace_iterator *iter) |
1952 | { | |
1953 | struct trace_array_cpu *data; | |
1954 | int cpu; | |
1955 | ||
ab46428c | 1956 | for_each_tracing_cpu(cpu) { |
bc0c38d1 SR |
1957 | data = iter->tr->data[cpu]; |
1958 | ||
b3806b43 SR |
1959 | if (head_page(data) && data->trace_idx && |
1960 | (data->trace_tail != data->trace_head || | |
1961 | data->trace_tail_idx != data->trace_head_idx)) | |
bc0c38d1 SR |
1962 | return 0; |
1963 | } | |
1964 | return 1; | |
1965 | } | |
1966 | ||
f9896bf3 IM |
1967 | static int print_trace_line(struct trace_iterator *iter) |
1968 | { | |
72829bc3 TG |
1969 | if (iter->trace && iter->trace->print_line) |
1970 | return iter->trace->print_line(iter); | |
1971 | ||
cb0f12aa IM |
1972 | if (trace_flags & TRACE_ITER_BIN) |
1973 | return print_bin_fmt(iter); | |
1974 | ||
5e3ca0ec IM |
1975 | if (trace_flags & TRACE_ITER_HEX) |
1976 | return print_hex_fmt(iter); | |
1977 | ||
f9896bf3 IM |
1978 | if (trace_flags & TRACE_ITER_RAW) |
1979 | return print_raw_fmt(iter); | |
1980 | ||
1981 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) | |
1982 | return print_lat_fmt(iter, iter->idx, iter->cpu); | |
1983 | ||
1984 | return print_trace_fmt(iter); | |
1985 | } | |
1986 | ||
bc0c38d1 SR |
1987 | static int s_show(struct seq_file *m, void *v) |
1988 | { | |
1989 | struct trace_iterator *iter = v; | |
1990 | ||
1991 | if (iter->ent == NULL) { | |
1992 | if (iter->tr) { | |
1993 | seq_printf(m, "# tracer: %s\n", iter->trace->name); | |
1994 | seq_puts(m, "#\n"); | |
1995 | } | |
1996 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) { | |
1997 | /* print nothing if the buffers are empty */ | |
1998 | if (trace_empty(iter)) | |
1999 | return 0; | |
2000 | print_trace_header(m, iter); | |
2001 | if (!(trace_flags & TRACE_ITER_VERBOSE)) | |
2002 | print_lat_help_header(m); | |
2003 | } else { | |
2004 | if (!(trace_flags & TRACE_ITER_VERBOSE)) | |
2005 | print_func_help_header(m); | |
2006 | } | |
2007 | } else { | |
f9896bf3 | 2008 | print_trace_line(iter); |
214023c3 | 2009 | trace_print_seq(m, &iter->seq); |
bc0c38d1 SR |
2010 | } |
2011 | ||
2012 | return 0; | |
2013 | } | |
2014 | ||
2015 | static struct seq_operations tracer_seq_ops = { | |
4bf39a94 IM |
2016 | .start = s_start, |
2017 | .next = s_next, | |
2018 | .stop = s_stop, | |
2019 | .show = s_show, | |
bc0c38d1 SR |
2020 | }; |
2021 | ||
e309b41d | 2022 | static struct trace_iterator * |
bc0c38d1 SR |
2023 | __tracing_open(struct inode *inode, struct file *file, int *ret) |
2024 | { | |
2025 | struct trace_iterator *iter; | |
2026 | ||
60a11774 SR |
2027 | if (tracing_disabled) { |
2028 | *ret = -ENODEV; | |
2029 | return NULL; | |
2030 | } | |
2031 | ||
bc0c38d1 SR |
2032 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); |
2033 | if (!iter) { | |
2034 | *ret = -ENOMEM; | |
2035 | goto out; | |
2036 | } | |
2037 | ||
2038 | mutex_lock(&trace_types_lock); | |
2039 | if (current_trace && current_trace->print_max) | |
2040 | iter->tr = &max_tr; | |
2041 | else | |
2042 | iter->tr = inode->i_private; | |
2043 | iter->trace = current_trace; | |
2044 | iter->pos = -1; | |
2045 | ||
2046 | /* TODO stop tracer */ | |
2047 | *ret = seq_open(file, &tracer_seq_ops); | |
2048 | if (!*ret) { | |
2049 | struct seq_file *m = file->private_data; | |
2050 | m->private = iter; | |
2051 | ||
2052 | /* stop the trace while dumping */ | |
60bc0800 | 2053 | if (iter->tr->ctrl) { |
bc0c38d1 | 2054 | tracer_enabled = 0; |
60bc0800 SR |
2055 | ftrace_function_enabled = 0; |
2056 | } | |
bc0c38d1 SR |
2057 | |
2058 | if (iter->trace && iter->trace->open) | |
2059 | iter->trace->open(iter); | |
2060 | } else { | |
2061 | kfree(iter); | |
2062 | iter = NULL; | |
2063 | } | |
2064 | mutex_unlock(&trace_types_lock); | |
2065 | ||
2066 | out: | |
2067 | return iter; | |
2068 | } | |
2069 | ||
2070 | int tracing_open_generic(struct inode *inode, struct file *filp) | |
2071 | { | |
60a11774 SR |
2072 | if (tracing_disabled) |
2073 | return -ENODEV; | |
2074 | ||
bc0c38d1 SR |
2075 | filp->private_data = inode->i_private; |
2076 | return 0; | |
2077 | } | |
2078 | ||
2079 | int tracing_release(struct inode *inode, struct file *file) | |
2080 | { | |
2081 | struct seq_file *m = (struct seq_file *)file->private_data; | |
2082 | struct trace_iterator *iter = m->private; | |
2083 | ||
2084 | mutex_lock(&trace_types_lock); | |
2085 | if (iter->trace && iter->trace->close) | |
2086 | iter->trace->close(iter); | |
2087 | ||
2088 | /* reenable tracing if it was previously enabled */ | |
60bc0800 | 2089 | if (iter->tr->ctrl) { |
bc0c38d1 | 2090 | tracer_enabled = 1; |
60bc0800 SR |
2091 | /* |
2092 | * It is safe to enable function tracing even if it | |
2093 | * isn't used | |
2094 | */ | |
2095 | ftrace_function_enabled = 1; | |
2096 | } | |
bc0c38d1 SR |
2097 | mutex_unlock(&trace_types_lock); |
2098 | ||
2099 | seq_release(inode, file); | |
2100 | kfree(iter); | |
2101 | return 0; | |
2102 | } | |
2103 | ||
2104 | static int tracing_open(struct inode *inode, struct file *file) | |
2105 | { | |
2106 | int ret; | |
2107 | ||
2108 | __tracing_open(inode, file, &ret); | |
2109 | ||
2110 | return ret; | |
2111 | } | |
2112 | ||
2113 | static int tracing_lt_open(struct inode *inode, struct file *file) | |
2114 | { | |
2115 | struct trace_iterator *iter; | |
2116 | int ret; | |
2117 | ||
2118 | iter = __tracing_open(inode, file, &ret); | |
2119 | ||
2120 | if (!ret) | |
2121 | iter->iter_flags |= TRACE_FILE_LAT_FMT; | |
2122 | ||
2123 | return ret; | |
2124 | } | |
2125 | ||
2126 | ||
e309b41d | 2127 | static void * |
bc0c38d1 SR |
2128 | t_next(struct seq_file *m, void *v, loff_t *pos) |
2129 | { | |
2130 | struct tracer *t = m->private; | |
2131 | ||
2132 | (*pos)++; | |
2133 | ||
2134 | if (t) | |
2135 | t = t->next; | |
2136 | ||
2137 | m->private = t; | |
2138 | ||
2139 | return t; | |
2140 | } | |
2141 | ||
2142 | static void *t_start(struct seq_file *m, loff_t *pos) | |
2143 | { | |
2144 | struct tracer *t = m->private; | |
2145 | loff_t l = 0; | |
2146 | ||
2147 | mutex_lock(&trace_types_lock); | |
2148 | for (; t && l < *pos; t = t_next(m, t, &l)) | |
2149 | ; | |
2150 | ||
2151 | return t; | |
2152 | } | |
2153 | ||
2154 | static void t_stop(struct seq_file *m, void *p) | |
2155 | { | |
2156 | mutex_unlock(&trace_types_lock); | |
2157 | } | |
2158 | ||
2159 | static int t_show(struct seq_file *m, void *v) | |
2160 | { | |
2161 | struct tracer *t = v; | |
2162 | ||
2163 | if (!t) | |
2164 | return 0; | |
2165 | ||
2166 | seq_printf(m, "%s", t->name); | |
2167 | if (t->next) | |
2168 | seq_putc(m, ' '); | |
2169 | else | |
2170 | seq_putc(m, '\n'); | |
2171 | ||
2172 | return 0; | |
2173 | } | |
2174 | ||
2175 | static struct seq_operations show_traces_seq_ops = { | |
4bf39a94 IM |
2176 | .start = t_start, |
2177 | .next = t_next, | |
2178 | .stop = t_stop, | |
2179 | .show = t_show, | |
bc0c38d1 SR |
2180 | }; |
2181 | ||
2182 | static int show_traces_open(struct inode *inode, struct file *file) | |
2183 | { | |
2184 | int ret; | |
2185 | ||
60a11774 SR |
2186 | if (tracing_disabled) |
2187 | return -ENODEV; | |
2188 | ||
bc0c38d1 SR |
2189 | ret = seq_open(file, &show_traces_seq_ops); |
2190 | if (!ret) { | |
2191 | struct seq_file *m = file->private_data; | |
2192 | m->private = trace_types; | |
2193 | } | |
2194 | ||
2195 | return ret; | |
2196 | } | |
2197 | ||
2198 | static struct file_operations tracing_fops = { | |
4bf39a94 IM |
2199 | .open = tracing_open, |
2200 | .read = seq_read, | |
2201 | .llseek = seq_lseek, | |
2202 | .release = tracing_release, | |
bc0c38d1 SR |
2203 | }; |
2204 | ||
2205 | static struct file_operations tracing_lt_fops = { | |
4bf39a94 IM |
2206 | .open = tracing_lt_open, |
2207 | .read = seq_read, | |
2208 | .llseek = seq_lseek, | |
2209 | .release = tracing_release, | |
bc0c38d1 SR |
2210 | }; |
2211 | ||
2212 | static struct file_operations show_traces_fops = { | |
c7078de1 IM |
2213 | .open = show_traces_open, |
2214 | .read = seq_read, | |
2215 | .release = seq_release, | |
2216 | }; | |
2217 | ||
36dfe925 IM |
2218 | /* |
2219 | * Only trace on a CPU if the bitmask is set: | |
2220 | */ | |
2221 | static cpumask_t tracing_cpumask = CPU_MASK_ALL; | |
2222 | ||
2223 | /* | |
2224 | * When tracing/tracing_cpu_mask is modified then this holds | |
2225 | * the new bitmask we are about to install: | |
2226 | */ | |
2227 | static cpumask_t tracing_cpumask_new; | |
2228 | ||
2229 | /* | |
2230 | * The tracer itself will not take this lock, but still we want | |
2231 | * to provide a consistent cpumask to user-space: | |
2232 | */ | |
2233 | static DEFINE_MUTEX(tracing_cpumask_update_lock); | |
2234 | ||
2235 | /* | |
2236 | * Temporary storage for the character representation of the | |
2237 | * CPU bitmask (and one more byte for the newline): | |
2238 | */ | |
2239 | static char mask_str[NR_CPUS + 1]; | |
2240 | ||
c7078de1 IM |
2241 | static ssize_t |
2242 | tracing_cpumask_read(struct file *filp, char __user *ubuf, | |
2243 | size_t count, loff_t *ppos) | |
2244 | { | |
36dfe925 | 2245 | int len; |
c7078de1 IM |
2246 | |
2247 | mutex_lock(&tracing_cpumask_update_lock); | |
36dfe925 IM |
2248 | |
2249 | len = cpumask_scnprintf(mask_str, count, tracing_cpumask); | |
2250 | if (count - len < 2) { | |
2251 | count = -EINVAL; | |
2252 | goto out_err; | |
2253 | } | |
2254 | len += sprintf(mask_str + len, "\n"); | |
2255 | count = simple_read_from_buffer(ubuf, count, ppos, mask_str, NR_CPUS+1); | |
2256 | ||
2257 | out_err: | |
c7078de1 IM |
2258 | mutex_unlock(&tracing_cpumask_update_lock); |
2259 | ||
2260 | return count; | |
2261 | } | |
2262 | ||
2263 | static ssize_t | |
2264 | tracing_cpumask_write(struct file *filp, const char __user *ubuf, | |
2265 | size_t count, loff_t *ppos) | |
2266 | { | |
36dfe925 | 2267 | int err, cpu; |
c7078de1 IM |
2268 | |
2269 | mutex_lock(&tracing_cpumask_update_lock); | |
36dfe925 | 2270 | err = cpumask_parse_user(ubuf, count, tracing_cpumask_new); |
c7078de1 | 2271 | if (err) |
36dfe925 IM |
2272 | goto err_unlock; |
2273 | ||
92205c23 SR |
2274 | raw_local_irq_disable(); |
2275 | __raw_spin_lock(&ftrace_max_lock); | |
ab46428c | 2276 | for_each_tracing_cpu(cpu) { |
36dfe925 IM |
2277 | /* |
2278 | * Increase/decrease the disabled counter if we are | |
2279 | * about to flip a bit in the cpumask: | |
2280 | */ | |
2281 | if (cpu_isset(cpu, tracing_cpumask) && | |
2282 | !cpu_isset(cpu, tracing_cpumask_new)) { | |
2283 | atomic_inc(&global_trace.data[cpu]->disabled); | |
2284 | } | |
2285 | if (!cpu_isset(cpu, tracing_cpumask) && | |
2286 | cpu_isset(cpu, tracing_cpumask_new)) { | |
2287 | atomic_dec(&global_trace.data[cpu]->disabled); | |
2288 | } | |
2289 | } | |
92205c23 SR |
2290 | __raw_spin_unlock(&ftrace_max_lock); |
2291 | raw_local_irq_enable(); | |
36dfe925 IM |
2292 | |
2293 | tracing_cpumask = tracing_cpumask_new; | |
2294 | ||
2295 | mutex_unlock(&tracing_cpumask_update_lock); | |
c7078de1 IM |
2296 | |
2297 | return count; | |
36dfe925 IM |
2298 | |
2299 | err_unlock: | |
2300 | mutex_unlock(&tracing_cpumask_update_lock); | |
2301 | ||
2302 | return err; | |
c7078de1 IM |
2303 | } |
2304 | ||
2305 | static struct file_operations tracing_cpumask_fops = { | |
2306 | .open = tracing_open_generic, | |
2307 | .read = tracing_cpumask_read, | |
2308 | .write = tracing_cpumask_write, | |
bc0c38d1 SR |
2309 | }; |
2310 | ||
2311 | static ssize_t | |
2312 | tracing_iter_ctrl_read(struct file *filp, char __user *ubuf, | |
2313 | size_t cnt, loff_t *ppos) | |
2314 | { | |
2315 | char *buf; | |
2316 | int r = 0; | |
2317 | int len = 0; | |
2318 | int i; | |
2319 | ||
2320 | /* calulate max size */ | |
2321 | for (i = 0; trace_options[i]; i++) { | |
2322 | len += strlen(trace_options[i]); | |
2323 | len += 3; /* "no" and space */ | |
2324 | } | |
2325 | ||
2326 | /* +2 for \n and \0 */ | |
2327 | buf = kmalloc(len + 2, GFP_KERNEL); | |
2328 | if (!buf) | |
2329 | return -ENOMEM; | |
2330 | ||
2331 | for (i = 0; trace_options[i]; i++) { | |
2332 | if (trace_flags & (1 << i)) | |
2333 | r += sprintf(buf + r, "%s ", trace_options[i]); | |
2334 | else | |
2335 | r += sprintf(buf + r, "no%s ", trace_options[i]); | |
2336 | } | |
2337 | ||
2338 | r += sprintf(buf + r, "\n"); | |
2339 | WARN_ON(r >= len + 2); | |
2340 | ||
36dfe925 | 2341 | r = simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
2342 | |
2343 | kfree(buf); | |
2344 | ||
2345 | return r; | |
2346 | } | |
2347 | ||
2348 | static ssize_t | |
2349 | tracing_iter_ctrl_write(struct file *filp, const char __user *ubuf, | |
2350 | size_t cnt, loff_t *ppos) | |
2351 | { | |
2352 | char buf[64]; | |
2353 | char *cmp = buf; | |
2354 | int neg = 0; | |
2355 | int i; | |
2356 | ||
cffae437 SR |
2357 | if (cnt >= sizeof(buf)) |
2358 | return -EINVAL; | |
bc0c38d1 SR |
2359 | |
2360 | if (copy_from_user(&buf, ubuf, cnt)) | |
2361 | return -EFAULT; | |
2362 | ||
2363 | buf[cnt] = 0; | |
2364 | ||
2365 | if (strncmp(buf, "no", 2) == 0) { | |
2366 | neg = 1; | |
2367 | cmp += 2; | |
2368 | } | |
2369 | ||
2370 | for (i = 0; trace_options[i]; i++) { | |
2371 | int len = strlen(trace_options[i]); | |
2372 | ||
2373 | if (strncmp(cmp, trace_options[i], len) == 0) { | |
2374 | if (neg) | |
2375 | trace_flags &= ~(1 << i); | |
2376 | else | |
2377 | trace_flags |= (1 << i); | |
2378 | break; | |
2379 | } | |
2380 | } | |
442e544c IM |
2381 | /* |
2382 | * If no option could be set, return an error: | |
2383 | */ | |
2384 | if (!trace_options[i]) | |
2385 | return -EINVAL; | |
bc0c38d1 SR |
2386 | |
2387 | filp->f_pos += cnt; | |
2388 | ||
2389 | return cnt; | |
2390 | } | |
2391 | ||
2392 | static struct file_operations tracing_iter_fops = { | |
c7078de1 IM |
2393 | .open = tracing_open_generic, |
2394 | .read = tracing_iter_ctrl_read, | |
2395 | .write = tracing_iter_ctrl_write, | |
bc0c38d1 SR |
2396 | }; |
2397 | ||
7bd2f24c IM |
2398 | static const char readme_msg[] = |
2399 | "tracing mini-HOWTO:\n\n" | |
2400 | "# mkdir /debug\n" | |
2401 | "# mount -t debugfs nodev /debug\n\n" | |
2402 | "# cat /debug/tracing/available_tracers\n" | |
2403 | "wakeup preemptirqsoff preemptoff irqsoff ftrace sched_switch none\n\n" | |
2404 | "# cat /debug/tracing/current_tracer\n" | |
2405 | "none\n" | |
2406 | "# echo sched_switch > /debug/tracing/current_tracer\n" | |
2407 | "# cat /debug/tracing/current_tracer\n" | |
2408 | "sched_switch\n" | |
2409 | "# cat /debug/tracing/iter_ctrl\n" | |
2410 | "noprint-parent nosym-offset nosym-addr noverbose\n" | |
2411 | "# echo print-parent > /debug/tracing/iter_ctrl\n" | |
2412 | "# echo 1 > /debug/tracing/tracing_enabled\n" | |
2413 | "# cat /debug/tracing/trace > /tmp/trace.txt\n" | |
2414 | "echo 0 > /debug/tracing/tracing_enabled\n" | |
2415 | ; | |
2416 | ||
2417 | static ssize_t | |
2418 | tracing_readme_read(struct file *filp, char __user *ubuf, | |
2419 | size_t cnt, loff_t *ppos) | |
2420 | { | |
2421 | return simple_read_from_buffer(ubuf, cnt, ppos, | |
2422 | readme_msg, strlen(readme_msg)); | |
2423 | } | |
2424 | ||
2425 | static struct file_operations tracing_readme_fops = { | |
c7078de1 IM |
2426 | .open = tracing_open_generic, |
2427 | .read = tracing_readme_read, | |
7bd2f24c IM |
2428 | }; |
2429 | ||
bc0c38d1 SR |
2430 | static ssize_t |
2431 | tracing_ctrl_read(struct file *filp, char __user *ubuf, | |
2432 | size_t cnt, loff_t *ppos) | |
2433 | { | |
2434 | struct trace_array *tr = filp->private_data; | |
2435 | char buf[64]; | |
2436 | int r; | |
2437 | ||
2438 | r = sprintf(buf, "%ld\n", tr->ctrl); | |
4e3c3333 | 2439 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
2440 | } |
2441 | ||
2442 | static ssize_t | |
2443 | tracing_ctrl_write(struct file *filp, const char __user *ubuf, | |
2444 | size_t cnt, loff_t *ppos) | |
2445 | { | |
2446 | struct trace_array *tr = filp->private_data; | |
bc0c38d1 | 2447 | char buf[64]; |
c6caeeb1 SR |
2448 | long val; |
2449 | int ret; | |
bc0c38d1 | 2450 | |
cffae437 SR |
2451 | if (cnt >= sizeof(buf)) |
2452 | return -EINVAL; | |
bc0c38d1 SR |
2453 | |
2454 | if (copy_from_user(&buf, ubuf, cnt)) | |
2455 | return -EFAULT; | |
2456 | ||
2457 | buf[cnt] = 0; | |
2458 | ||
c6caeeb1 SR |
2459 | ret = strict_strtoul(buf, 10, &val); |
2460 | if (ret < 0) | |
2461 | return ret; | |
bc0c38d1 SR |
2462 | |
2463 | val = !!val; | |
2464 | ||
2465 | mutex_lock(&trace_types_lock); | |
2466 | if (tr->ctrl ^ val) { | |
2467 | if (val) | |
2468 | tracer_enabled = 1; | |
2469 | else | |
2470 | tracer_enabled = 0; | |
2471 | ||
2472 | tr->ctrl = val; | |
2473 | ||
2474 | if (current_trace && current_trace->ctrl_update) | |
2475 | current_trace->ctrl_update(tr); | |
2476 | } | |
2477 | mutex_unlock(&trace_types_lock); | |
2478 | ||
2479 | filp->f_pos += cnt; | |
2480 | ||
2481 | return cnt; | |
2482 | } | |
2483 | ||
2484 | static ssize_t | |
2485 | tracing_set_trace_read(struct file *filp, char __user *ubuf, | |
2486 | size_t cnt, loff_t *ppos) | |
2487 | { | |
2488 | char buf[max_tracer_type_len+2]; | |
2489 | int r; | |
2490 | ||
2491 | mutex_lock(&trace_types_lock); | |
2492 | if (current_trace) | |
2493 | r = sprintf(buf, "%s\n", current_trace->name); | |
2494 | else | |
2495 | r = sprintf(buf, "\n"); | |
2496 | mutex_unlock(&trace_types_lock); | |
2497 | ||
4bf39a94 | 2498 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
2499 | } |
2500 | ||
2501 | static ssize_t | |
2502 | tracing_set_trace_write(struct file *filp, const char __user *ubuf, | |
2503 | size_t cnt, loff_t *ppos) | |
2504 | { | |
2505 | struct trace_array *tr = &global_trace; | |
2506 | struct tracer *t; | |
2507 | char buf[max_tracer_type_len+1]; | |
2508 | int i; | |
2509 | ||
2510 | if (cnt > max_tracer_type_len) | |
2511 | cnt = max_tracer_type_len; | |
2512 | ||
2513 | if (copy_from_user(&buf, ubuf, cnt)) | |
2514 | return -EFAULT; | |
2515 | ||
2516 | buf[cnt] = 0; | |
2517 | ||
2518 | /* strip ending whitespace. */ | |
2519 | for (i = cnt - 1; i > 0 && isspace(buf[i]); i--) | |
2520 | buf[i] = 0; | |
2521 | ||
2522 | mutex_lock(&trace_types_lock); | |
2523 | for (t = trace_types; t; t = t->next) { | |
2524 | if (strcmp(t->name, buf) == 0) | |
2525 | break; | |
2526 | } | |
2527 | if (!t || t == current_trace) | |
2528 | goto out; | |
2529 | ||
2530 | if (current_trace && current_trace->reset) | |
2531 | current_trace->reset(tr); | |
2532 | ||
2533 | current_trace = t; | |
2534 | if (t->init) | |
2535 | t->init(tr); | |
2536 | ||
2537 | out: | |
2538 | mutex_unlock(&trace_types_lock); | |
2539 | ||
2540 | filp->f_pos += cnt; | |
2541 | ||
2542 | return cnt; | |
2543 | } | |
2544 | ||
2545 | static ssize_t | |
2546 | tracing_max_lat_read(struct file *filp, char __user *ubuf, | |
2547 | size_t cnt, loff_t *ppos) | |
2548 | { | |
2549 | unsigned long *ptr = filp->private_data; | |
2550 | char buf[64]; | |
2551 | int r; | |
2552 | ||
cffae437 | 2553 | r = snprintf(buf, sizeof(buf), "%ld\n", |
bc0c38d1 | 2554 | *ptr == (unsigned long)-1 ? -1 : nsecs_to_usecs(*ptr)); |
cffae437 SR |
2555 | if (r > sizeof(buf)) |
2556 | r = sizeof(buf); | |
4bf39a94 | 2557 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
2558 | } |
2559 | ||
2560 | static ssize_t | |
2561 | tracing_max_lat_write(struct file *filp, const char __user *ubuf, | |
2562 | size_t cnt, loff_t *ppos) | |
2563 | { | |
2564 | long *ptr = filp->private_data; | |
bc0c38d1 | 2565 | char buf[64]; |
c6caeeb1 SR |
2566 | long val; |
2567 | int ret; | |
bc0c38d1 | 2568 | |
cffae437 SR |
2569 | if (cnt >= sizeof(buf)) |
2570 | return -EINVAL; | |
bc0c38d1 SR |
2571 | |
2572 | if (copy_from_user(&buf, ubuf, cnt)) | |
2573 | return -EFAULT; | |
2574 | ||
2575 | buf[cnt] = 0; | |
2576 | ||
c6caeeb1 SR |
2577 | ret = strict_strtoul(buf, 10, &val); |
2578 | if (ret < 0) | |
2579 | return ret; | |
bc0c38d1 SR |
2580 | |
2581 | *ptr = val * 1000; | |
2582 | ||
2583 | return cnt; | |
2584 | } | |
2585 | ||
b3806b43 SR |
2586 | static atomic_t tracing_reader; |
2587 | ||
2588 | static int tracing_open_pipe(struct inode *inode, struct file *filp) | |
2589 | { | |
2590 | struct trace_iterator *iter; | |
2591 | ||
2592 | if (tracing_disabled) | |
2593 | return -ENODEV; | |
2594 | ||
2595 | /* We only allow for reader of the pipe */ | |
2596 | if (atomic_inc_return(&tracing_reader) != 1) { | |
2597 | atomic_dec(&tracing_reader); | |
2598 | return -EBUSY; | |
2599 | } | |
2600 | ||
2601 | /* create a buffer to store the information to pass to userspace */ | |
2602 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); | |
2603 | if (!iter) | |
2604 | return -ENOMEM; | |
2605 | ||
107bad8b | 2606 | mutex_lock(&trace_types_lock); |
b3806b43 | 2607 | iter->tr = &global_trace; |
72829bc3 | 2608 | iter->trace = current_trace; |
b3806b43 SR |
2609 | filp->private_data = iter; |
2610 | ||
107bad8b SR |
2611 | if (iter->trace->pipe_open) |
2612 | iter->trace->pipe_open(iter); | |
2613 | mutex_unlock(&trace_types_lock); | |
2614 | ||
b3806b43 SR |
2615 | return 0; |
2616 | } | |
2617 | ||
2618 | static int tracing_release_pipe(struct inode *inode, struct file *file) | |
2619 | { | |
2620 | struct trace_iterator *iter = file->private_data; | |
2621 | ||
2622 | kfree(iter); | |
2623 | atomic_dec(&tracing_reader); | |
2624 | ||
2625 | return 0; | |
2626 | } | |
2627 | ||
2a2cc8f7 SSP |
2628 | static unsigned int |
2629 | tracing_poll_pipe(struct file *filp, poll_table *poll_table) | |
2630 | { | |
2631 | struct trace_iterator *iter = filp->private_data; | |
2632 | ||
2633 | if (trace_flags & TRACE_ITER_BLOCK) { | |
2634 | /* | |
2635 | * Always select as readable when in blocking mode | |
2636 | */ | |
2637 | return POLLIN | POLLRDNORM; | |
afc2abc0 | 2638 | } else { |
2a2cc8f7 SSP |
2639 | if (!trace_empty(iter)) |
2640 | return POLLIN | POLLRDNORM; | |
2641 | poll_wait(filp, &trace_wait, poll_table); | |
2642 | if (!trace_empty(iter)) | |
2643 | return POLLIN | POLLRDNORM; | |
2644 | ||
2645 | return 0; | |
2646 | } | |
2647 | } | |
2648 | ||
b3806b43 SR |
2649 | /* |
2650 | * Consumer reader. | |
2651 | */ | |
2652 | static ssize_t | |
2653 | tracing_read_pipe(struct file *filp, char __user *ubuf, | |
2654 | size_t cnt, loff_t *ppos) | |
2655 | { | |
2656 | struct trace_iterator *iter = filp->private_data; | |
2657 | struct trace_array_cpu *data; | |
2658 | static cpumask_t mask; | |
b3806b43 | 2659 | unsigned long flags; |
25770467 | 2660 | #ifdef CONFIG_FTRACE |
2e0f5761 | 2661 | int ftrace_save; |
25770467 | 2662 | #endif |
b3806b43 | 2663 | int cpu; |
6c6c2796 | 2664 | ssize_t sret; |
b3806b43 SR |
2665 | |
2666 | /* return any leftover data */ | |
6c6c2796 PP |
2667 | sret = trace_seq_to_user(&iter->seq, ubuf, cnt); |
2668 | if (sret != -EBUSY) | |
2669 | return sret; | |
2670 | sret = 0; | |
b3806b43 | 2671 | |
6c6c2796 | 2672 | trace_seq_reset(&iter->seq); |
b3806b43 | 2673 | |
107bad8b SR |
2674 | mutex_lock(&trace_types_lock); |
2675 | if (iter->trace->read) { | |
6c6c2796 PP |
2676 | sret = iter->trace->read(iter, filp, ubuf, cnt, ppos); |
2677 | if (sret) | |
107bad8b | 2678 | goto out; |
107bad8b SR |
2679 | } |
2680 | ||
b3806b43 | 2681 | while (trace_empty(iter)) { |
2dc8f095 | 2682 | |
107bad8b | 2683 | if ((filp->f_flags & O_NONBLOCK)) { |
6c6c2796 | 2684 | sret = -EAGAIN; |
107bad8b SR |
2685 | goto out; |
2686 | } | |
2dc8f095 | 2687 | |
b3806b43 SR |
2688 | /* |
2689 | * This is a make-shift waitqueue. The reason we don't use | |
2690 | * an actual wait queue is because: | |
2691 | * 1) we only ever have one waiter | |
2692 | * 2) the tracing, traces all functions, we don't want | |
2693 | * the overhead of calling wake_up and friends | |
2694 | * (and tracing them too) | |
2695 | * Anyway, this is really very primitive wakeup. | |
2696 | */ | |
2697 | set_current_state(TASK_INTERRUPTIBLE); | |
2698 | iter->tr->waiter = current; | |
2699 | ||
107bad8b SR |
2700 | mutex_unlock(&trace_types_lock); |
2701 | ||
9fe068e9 IM |
2702 | /* sleep for 100 msecs, and try again. */ |
2703 | schedule_timeout(HZ/10); | |
b3806b43 | 2704 | |
107bad8b SR |
2705 | mutex_lock(&trace_types_lock); |
2706 | ||
b3806b43 SR |
2707 | iter->tr->waiter = NULL; |
2708 | ||
107bad8b | 2709 | if (signal_pending(current)) { |
6c6c2796 | 2710 | sret = -EINTR; |
107bad8b SR |
2711 | goto out; |
2712 | } | |
b3806b43 | 2713 | |
84527997 | 2714 | if (iter->trace != current_trace) |
107bad8b | 2715 | goto out; |
84527997 | 2716 | |
b3806b43 SR |
2717 | /* |
2718 | * We block until we read something and tracing is disabled. | |
2719 | * We still block if tracing is disabled, but we have never | |
2720 | * read anything. This allows a user to cat this file, and | |
2721 | * then enable tracing. But after we have read something, | |
2722 | * we give an EOF when tracing is again disabled. | |
2723 | * | |
2724 | * iter->pos will be 0 if we haven't read anything. | |
2725 | */ | |
2726 | if (!tracer_enabled && iter->pos) | |
2727 | break; | |
2728 | ||
2729 | continue; | |
2730 | } | |
2731 | ||
2732 | /* stop when tracing is finished */ | |
2733 | if (trace_empty(iter)) | |
107bad8b | 2734 | goto out; |
b3806b43 SR |
2735 | |
2736 | if (cnt >= PAGE_SIZE) | |
2737 | cnt = PAGE_SIZE - 1; | |
2738 | ||
53d0aa77 | 2739 | /* reset all but tr, trace, and overruns */ |
53d0aa77 SR |
2740 | memset(&iter->seq, 0, |
2741 | sizeof(struct trace_iterator) - | |
2742 | offsetof(struct trace_iterator, seq)); | |
4823ed7e | 2743 | iter->pos = -1; |
b3806b43 SR |
2744 | |
2745 | /* | |
2746 | * We need to stop all tracing on all CPUS to read the | |
2747 | * the next buffer. This is a bit expensive, but is | |
2748 | * not done often. We fill all what we can read, | |
2749 | * and then release the locks again. | |
2750 | */ | |
2751 | ||
2752 | cpus_clear(mask); | |
2753 | local_irq_save(flags); | |
25770467 | 2754 | #ifdef CONFIG_FTRACE |
2e0f5761 IM |
2755 | ftrace_save = ftrace_enabled; |
2756 | ftrace_enabled = 0; | |
25770467 | 2757 | #endif |
2e0f5761 | 2758 | smp_wmb(); |
ab46428c | 2759 | for_each_tracing_cpu(cpu) { |
b3806b43 SR |
2760 | data = iter->tr->data[cpu]; |
2761 | ||
2762 | if (!head_page(data) || !data->trace_idx) | |
2763 | continue; | |
2764 | ||
2765 | atomic_inc(&data->disabled); | |
b3806b43 SR |
2766 | cpu_set(cpu, mask); |
2767 | } | |
2768 | ||
2e0f5761 IM |
2769 | for_each_cpu_mask(cpu, mask) { |
2770 | data = iter->tr->data[cpu]; | |
92205c23 | 2771 | __raw_spin_lock(&data->lock); |
53d0aa77 SR |
2772 | |
2773 | if (data->overrun > iter->last_overrun[cpu]) | |
2774 | iter->overrun[cpu] += | |
2775 | data->overrun - iter->last_overrun[cpu]; | |
2776 | iter->last_overrun[cpu] = data->overrun; | |
2e0f5761 IM |
2777 | } |
2778 | ||
088b1e42 | 2779 | while (find_next_entry_inc(iter) != NULL) { |
6c6c2796 | 2780 | int ret; |
088b1e42 SR |
2781 | int len = iter->seq.len; |
2782 | ||
f9896bf3 | 2783 | ret = print_trace_line(iter); |
088b1e42 SR |
2784 | if (!ret) { |
2785 | /* don't print partial lines */ | |
2786 | iter->seq.len = len; | |
b3806b43 | 2787 | break; |
088b1e42 | 2788 | } |
b3806b43 SR |
2789 | |
2790 | trace_consume(iter); | |
2791 | ||
2792 | if (iter->seq.len >= cnt) | |
2793 | break; | |
b3806b43 SR |
2794 | } |
2795 | ||
d4c5a2f5 | 2796 | for_each_cpu_mask(cpu, mask) { |
b3806b43 | 2797 | data = iter->tr->data[cpu]; |
92205c23 | 2798 | __raw_spin_unlock(&data->lock); |
2e0f5761 IM |
2799 | } |
2800 | ||
2801 | for_each_cpu_mask(cpu, mask) { | |
2802 | data = iter->tr->data[cpu]; | |
b3806b43 SR |
2803 | atomic_dec(&data->disabled); |
2804 | } | |
25770467 | 2805 | #ifdef CONFIG_FTRACE |
2e0f5761 | 2806 | ftrace_enabled = ftrace_save; |
25770467 | 2807 | #endif |
b3806b43 SR |
2808 | local_irq_restore(flags); |
2809 | ||
2810 | /* Now copy what we have to the user */ | |
6c6c2796 PP |
2811 | sret = trace_seq_to_user(&iter->seq, ubuf, cnt); |
2812 | if (iter->seq.readpos >= iter->seq.len) | |
b3806b43 | 2813 | trace_seq_reset(&iter->seq); |
6c6c2796 PP |
2814 | if (sret == -EBUSY) |
2815 | sret = 0; | |
b3806b43 | 2816 | |
107bad8b SR |
2817 | out: |
2818 | mutex_unlock(&trace_types_lock); | |
2819 | ||
6c6c2796 | 2820 | return sret; |
b3806b43 SR |
2821 | } |
2822 | ||
a98a3c3f SR |
2823 | static ssize_t |
2824 | tracing_entries_read(struct file *filp, char __user *ubuf, | |
2825 | size_t cnt, loff_t *ppos) | |
2826 | { | |
2827 | struct trace_array *tr = filp->private_data; | |
2828 | char buf[64]; | |
2829 | int r; | |
2830 | ||
2831 | r = sprintf(buf, "%lu\n", tr->entries); | |
2832 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
2833 | } | |
2834 | ||
2835 | static ssize_t | |
2836 | tracing_entries_write(struct file *filp, const char __user *ubuf, | |
2837 | size_t cnt, loff_t *ppos) | |
2838 | { | |
2839 | unsigned long val; | |
2840 | char buf[64]; | |
19384c03 | 2841 | int i, ret; |
a98a3c3f | 2842 | |
cffae437 SR |
2843 | if (cnt >= sizeof(buf)) |
2844 | return -EINVAL; | |
a98a3c3f SR |
2845 | |
2846 | if (copy_from_user(&buf, ubuf, cnt)) | |
2847 | return -EFAULT; | |
2848 | ||
2849 | buf[cnt] = 0; | |
2850 | ||
c6caeeb1 SR |
2851 | ret = strict_strtoul(buf, 10, &val); |
2852 | if (ret < 0) | |
2853 | return ret; | |
a98a3c3f SR |
2854 | |
2855 | /* must have at least 1 entry */ | |
2856 | if (!val) | |
2857 | return -EINVAL; | |
2858 | ||
2859 | mutex_lock(&trace_types_lock); | |
2860 | ||
2861 | if (current_trace != &no_tracer) { | |
2862 | cnt = -EBUSY; | |
2863 | pr_info("ftrace: set current_tracer to none" | |
2864 | " before modifying buffer size\n"); | |
2865 | goto out; | |
2866 | } | |
2867 | ||
2868 | if (val > global_trace.entries) { | |
3eefae99 SR |
2869 | long pages_requested; |
2870 | unsigned long freeable_pages; | |
2871 | ||
2872 | /* make sure we have enough memory before mapping */ | |
2873 | pages_requested = | |
2874 | (val + (ENTRIES_PER_PAGE-1)) / ENTRIES_PER_PAGE; | |
2875 | ||
2876 | /* account for each buffer (and max_tr) */ | |
2877 | pages_requested *= tracing_nr_buffers * 2; | |
2878 | ||
2879 | /* Check for overflow */ | |
2880 | if (pages_requested < 0) { | |
2881 | cnt = -ENOMEM; | |
2882 | goto out; | |
2883 | } | |
2884 | ||
2885 | freeable_pages = determine_dirtyable_memory(); | |
2886 | ||
2887 | /* we only allow to request 1/4 of useable memory */ | |
2888 | if (pages_requested > | |
2889 | ((freeable_pages + tracing_pages_allocated) / 4)) { | |
2890 | cnt = -ENOMEM; | |
2891 | goto out; | |
2892 | } | |
2893 | ||
a98a3c3f SR |
2894 | while (global_trace.entries < val) { |
2895 | if (trace_alloc_page()) { | |
2896 | cnt = -ENOMEM; | |
2897 | goto out; | |
2898 | } | |
3eefae99 SR |
2899 | /* double check that we don't go over the known pages */ |
2900 | if (tracing_pages_allocated > pages_requested) | |
2901 | break; | |
a98a3c3f | 2902 | } |
3eefae99 | 2903 | |
a98a3c3f SR |
2904 | } else { |
2905 | /* include the number of entries in val (inc of page entries) */ | |
2906 | while (global_trace.entries > val + (ENTRIES_PER_PAGE - 1)) | |
2907 | trace_free_page(); | |
2908 | } | |
2909 | ||
19384c03 SR |
2910 | /* check integrity */ |
2911 | for_each_tracing_cpu(i) | |
2912 | check_pages(global_trace.data[i]); | |
2913 | ||
a98a3c3f SR |
2914 | filp->f_pos += cnt; |
2915 | ||
19384c03 SR |
2916 | /* If check pages failed, return ENOMEM */ |
2917 | if (tracing_disabled) | |
2918 | cnt = -ENOMEM; | |
a98a3c3f SR |
2919 | out: |
2920 | max_tr.entries = global_trace.entries; | |
2921 | mutex_unlock(&trace_types_lock); | |
2922 | ||
2923 | return cnt; | |
2924 | } | |
2925 | ||
bc0c38d1 | 2926 | static struct file_operations tracing_max_lat_fops = { |
4bf39a94 IM |
2927 | .open = tracing_open_generic, |
2928 | .read = tracing_max_lat_read, | |
2929 | .write = tracing_max_lat_write, | |
bc0c38d1 SR |
2930 | }; |
2931 | ||
2932 | static struct file_operations tracing_ctrl_fops = { | |
4bf39a94 IM |
2933 | .open = tracing_open_generic, |
2934 | .read = tracing_ctrl_read, | |
2935 | .write = tracing_ctrl_write, | |
bc0c38d1 SR |
2936 | }; |
2937 | ||
2938 | static struct file_operations set_tracer_fops = { | |
4bf39a94 IM |
2939 | .open = tracing_open_generic, |
2940 | .read = tracing_set_trace_read, | |
2941 | .write = tracing_set_trace_write, | |
bc0c38d1 SR |
2942 | }; |
2943 | ||
b3806b43 | 2944 | static struct file_operations tracing_pipe_fops = { |
4bf39a94 | 2945 | .open = tracing_open_pipe, |
2a2cc8f7 | 2946 | .poll = tracing_poll_pipe, |
4bf39a94 IM |
2947 | .read = tracing_read_pipe, |
2948 | .release = tracing_release_pipe, | |
b3806b43 SR |
2949 | }; |
2950 | ||
a98a3c3f SR |
2951 | static struct file_operations tracing_entries_fops = { |
2952 | .open = tracing_open_generic, | |
2953 | .read = tracing_entries_read, | |
2954 | .write = tracing_entries_write, | |
2955 | }; | |
2956 | ||
bc0c38d1 SR |
2957 | #ifdef CONFIG_DYNAMIC_FTRACE |
2958 | ||
2959 | static ssize_t | |
2960 | tracing_read_long(struct file *filp, char __user *ubuf, | |
2961 | size_t cnt, loff_t *ppos) | |
2962 | { | |
2963 | unsigned long *p = filp->private_data; | |
2964 | char buf[64]; | |
2965 | int r; | |
2966 | ||
2967 | r = sprintf(buf, "%ld\n", *p); | |
4bf39a94 IM |
2968 | |
2969 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
bc0c38d1 SR |
2970 | } |
2971 | ||
2972 | static struct file_operations tracing_read_long_fops = { | |
4bf39a94 IM |
2973 | .open = tracing_open_generic, |
2974 | .read = tracing_read_long, | |
bc0c38d1 SR |
2975 | }; |
2976 | #endif | |
2977 | ||
2978 | static struct dentry *d_tracer; | |
2979 | ||
2980 | struct dentry *tracing_init_dentry(void) | |
2981 | { | |
2982 | static int once; | |
2983 | ||
2984 | if (d_tracer) | |
2985 | return d_tracer; | |
2986 | ||
2987 | d_tracer = debugfs_create_dir("tracing", NULL); | |
2988 | ||
2989 | if (!d_tracer && !once) { | |
2990 | once = 1; | |
2991 | pr_warning("Could not create debugfs directory 'tracing'\n"); | |
2992 | return NULL; | |
2993 | } | |
2994 | ||
2995 | return d_tracer; | |
2996 | } | |
2997 | ||
60a11774 SR |
2998 | #ifdef CONFIG_FTRACE_SELFTEST |
2999 | /* Let selftest have access to static functions in this file */ | |
3000 | #include "trace_selftest.c" | |
3001 | #endif | |
3002 | ||
bc0c38d1 SR |
3003 | static __init void tracer_init_debugfs(void) |
3004 | { | |
3005 | struct dentry *d_tracer; | |
3006 | struct dentry *entry; | |
3007 | ||
3008 | d_tracer = tracing_init_dentry(); | |
3009 | ||
3010 | entry = debugfs_create_file("tracing_enabled", 0644, d_tracer, | |
3011 | &global_trace, &tracing_ctrl_fops); | |
3012 | if (!entry) | |
3013 | pr_warning("Could not create debugfs 'tracing_enabled' entry\n"); | |
3014 | ||
3015 | entry = debugfs_create_file("iter_ctrl", 0644, d_tracer, | |
3016 | NULL, &tracing_iter_fops); | |
3017 | if (!entry) | |
3018 | pr_warning("Could not create debugfs 'iter_ctrl' entry\n"); | |
3019 | ||
c7078de1 IM |
3020 | entry = debugfs_create_file("tracing_cpumask", 0644, d_tracer, |
3021 | NULL, &tracing_cpumask_fops); | |
3022 | if (!entry) | |
3023 | pr_warning("Could not create debugfs 'tracing_cpumask' entry\n"); | |
3024 | ||
bc0c38d1 SR |
3025 | entry = debugfs_create_file("latency_trace", 0444, d_tracer, |
3026 | &global_trace, &tracing_lt_fops); | |
3027 | if (!entry) | |
3028 | pr_warning("Could not create debugfs 'latency_trace' entry\n"); | |
3029 | ||
3030 | entry = debugfs_create_file("trace", 0444, d_tracer, | |
3031 | &global_trace, &tracing_fops); | |
3032 | if (!entry) | |
3033 | pr_warning("Could not create debugfs 'trace' entry\n"); | |
3034 | ||
3035 | entry = debugfs_create_file("available_tracers", 0444, d_tracer, | |
3036 | &global_trace, &show_traces_fops); | |
3037 | if (!entry) | |
98a983aa | 3038 | pr_warning("Could not create debugfs 'available_tracers' entry\n"); |
bc0c38d1 SR |
3039 | |
3040 | entry = debugfs_create_file("current_tracer", 0444, d_tracer, | |
3041 | &global_trace, &set_tracer_fops); | |
3042 | if (!entry) | |
98a983aa | 3043 | pr_warning("Could not create debugfs 'current_tracer' entry\n"); |
bc0c38d1 SR |
3044 | |
3045 | entry = debugfs_create_file("tracing_max_latency", 0644, d_tracer, | |
3046 | &tracing_max_latency, | |
3047 | &tracing_max_lat_fops); | |
3048 | if (!entry) | |
3049 | pr_warning("Could not create debugfs " | |
3050 | "'tracing_max_latency' entry\n"); | |
3051 | ||
3052 | entry = debugfs_create_file("tracing_thresh", 0644, d_tracer, | |
3053 | &tracing_thresh, &tracing_max_lat_fops); | |
3054 | if (!entry) | |
3055 | pr_warning("Could not create debugfs " | |
98a983aa | 3056 | "'tracing_thresh' entry\n"); |
7bd2f24c IM |
3057 | entry = debugfs_create_file("README", 0644, d_tracer, |
3058 | NULL, &tracing_readme_fops); | |
3059 | if (!entry) | |
3060 | pr_warning("Could not create debugfs 'README' entry\n"); | |
3061 | ||
b3806b43 SR |
3062 | entry = debugfs_create_file("trace_pipe", 0644, d_tracer, |
3063 | NULL, &tracing_pipe_fops); | |
3064 | if (!entry) | |
3065 | pr_warning("Could not create debugfs " | |
98a983aa | 3066 | "'trace_pipe' entry\n"); |
bc0c38d1 | 3067 | |
a98a3c3f SR |
3068 | entry = debugfs_create_file("trace_entries", 0644, d_tracer, |
3069 | &global_trace, &tracing_entries_fops); | |
3070 | if (!entry) | |
3071 | pr_warning("Could not create debugfs " | |
98a983aa | 3072 | "'trace_entries' entry\n"); |
a98a3c3f | 3073 | |
bc0c38d1 SR |
3074 | #ifdef CONFIG_DYNAMIC_FTRACE |
3075 | entry = debugfs_create_file("dyn_ftrace_total_info", 0444, d_tracer, | |
3076 | &ftrace_update_tot_cnt, | |
3077 | &tracing_read_long_fops); | |
3078 | if (!entry) | |
3079 | pr_warning("Could not create debugfs " | |
3080 | "'dyn_ftrace_total_info' entry\n"); | |
3081 | #endif | |
d618b3e6 IM |
3082 | #ifdef CONFIG_SYSPROF_TRACER |
3083 | init_tracer_sysprof_debugfs(d_tracer); | |
3084 | #endif | |
bc0c38d1 SR |
3085 | } |
3086 | ||
dd0e545f SR |
3087 | #define TRACE_BUF_SIZE 1024 |
3088 | #define TRACE_PRINT_BUF_SIZE \ | |
3089 | (sizeof(struct trace_field) - offsetof(struct trace_field, print.buf)) | |
3090 | #define TRACE_CONT_BUF_SIZE sizeof(struct trace_field) | |
3091 | ||
dd0e545f SR |
3092 | int __ftrace_printk(unsigned long ip, const char *fmt, ...) |
3093 | { | |
3094 | struct trace_array *tr = &global_trace; | |
3095 | static DEFINE_SPINLOCK(trace_buf_lock); | |
3096 | static char trace_buf[TRACE_BUF_SIZE]; | |
3097 | struct trace_array_cpu *data; | |
3098 | struct trace_entry *entry; | |
3099 | unsigned long flags; | |
3100 | long disabled; | |
3101 | va_list ap; | |
3102 | int cpu, len = 0, write, written = 0; | |
3103 | ||
3104 | if (likely(!ftrace_function_enabled)) | |
3105 | return 0; | |
3106 | ||
3107 | local_irq_save(flags); | |
3108 | cpu = raw_smp_processor_id(); | |
3109 | data = tr->data[cpu]; | |
3110 | disabled = atomic_inc_return(&data->disabled); | |
3111 | ||
3112 | if (unlikely(disabled != 1 || !ftrace_function_enabled)) | |
3113 | goto out; | |
3114 | ||
3115 | spin_lock(&trace_buf_lock); | |
3116 | va_start(ap, fmt); | |
3117 | len = vsnprintf(trace_buf, TRACE_BUF_SIZE, fmt, ap); | |
3118 | va_end(ap); | |
3119 | ||
3120 | len = min(len, TRACE_BUF_SIZE-1); | |
3121 | trace_buf[len] = 0; | |
3122 | ||
3123 | __raw_spin_lock(&data->lock); | |
3124 | entry = tracing_get_trace_entry(tr, data); | |
3125 | tracing_generic_entry_update(entry, flags); | |
3126 | entry->type = TRACE_PRINT; | |
3127 | entry->field.print.ip = ip; | |
3128 | ||
3129 | write = min(len, (int)(TRACE_PRINT_BUF_SIZE-1)); | |
3130 | ||
3131 | memcpy(&entry->field.print.buf, trace_buf, write); | |
3132 | entry->field.print.buf[write] = 0; | |
3133 | written = write; | |
3134 | ||
3135 | if (written != len) | |
3136 | entry->field.flags |= TRACE_FLAG_CONT; | |
3137 | ||
3138 | while (written != len) { | |
3139 | entry = tracing_get_trace_entry(tr, data); | |
3140 | ||
3141 | entry->type = TRACE_CONT; | |
3142 | write = min(len - written, (int)(TRACE_CONT_BUF_SIZE-1)); | |
3143 | memcpy(&entry->cont.buf, trace_buf+written, write); | |
3144 | entry->cont.buf[write] = 0; | |
3145 | written += write; | |
3146 | } | |
3147 | __raw_spin_unlock(&data->lock); | |
3148 | ||
3149 | spin_unlock(&trace_buf_lock); | |
3150 | ||
3151 | out: | |
3152 | atomic_dec(&data->disabled); | |
3153 | local_irq_restore(flags); | |
3154 | ||
3155 | return len; | |
3156 | } | |
3157 | EXPORT_SYMBOL_GPL(__ftrace_printk); | |
3158 | ||
3f5a54e3 SR |
3159 | static int trace_panic_handler(struct notifier_block *this, |
3160 | unsigned long event, void *unused) | |
3161 | { | |
3162 | ftrace_dump(); | |
3163 | return NOTIFY_OK; | |
3164 | } | |
3165 | ||
3166 | static struct notifier_block trace_panic_notifier = { | |
3167 | .notifier_call = trace_panic_handler, | |
3168 | .next = NULL, | |
3169 | .priority = 150 /* priority: INT_MAX >= x >= 0 */ | |
3170 | }; | |
3171 | ||
3172 | static int trace_die_handler(struct notifier_block *self, | |
3173 | unsigned long val, | |
3174 | void *data) | |
3175 | { | |
3176 | switch (val) { | |
3177 | case DIE_OOPS: | |
3178 | ftrace_dump(); | |
3179 | break; | |
3180 | default: | |
3181 | break; | |
3182 | } | |
3183 | return NOTIFY_OK; | |
3184 | } | |
3185 | ||
3186 | static struct notifier_block trace_die_notifier = { | |
3187 | .notifier_call = trace_die_handler, | |
3188 | .priority = 200 | |
3189 | }; | |
3190 | ||
3191 | /* | |
3192 | * printk is set to max of 1024, we really don't need it that big. | |
3193 | * Nothing should be printing 1000 characters anyway. | |
3194 | */ | |
3195 | #define TRACE_MAX_PRINT 1000 | |
3196 | ||
3197 | /* | |
3198 | * Define here KERN_TRACE so that we have one place to modify | |
3199 | * it if we decide to change what log level the ftrace dump | |
3200 | * should be at. | |
3201 | */ | |
3202 | #define KERN_TRACE KERN_INFO | |
3203 | ||
3204 | static void | |
3205 | trace_printk_seq(struct trace_seq *s) | |
3206 | { | |
3207 | /* Probably should print a warning here. */ | |
3208 | if (s->len >= 1000) | |
3209 | s->len = 1000; | |
3210 | ||
3211 | /* should be zero ended, but we are paranoid. */ | |
3212 | s->buffer[s->len] = 0; | |
3213 | ||
3214 | printk(KERN_TRACE "%s", s->buffer); | |
3215 | ||
3216 | trace_seq_reset(s); | |
3217 | } | |
3218 | ||
3219 | ||
3220 | void ftrace_dump(void) | |
3221 | { | |
3222 | static DEFINE_SPINLOCK(ftrace_dump_lock); | |
3223 | /* use static because iter can be a bit big for the stack */ | |
3224 | static struct trace_iterator iter; | |
3225 | struct trace_array_cpu *data; | |
3226 | static cpumask_t mask; | |
3227 | static int dump_ran; | |
3228 | unsigned long flags; | |
3229 | int cnt = 0; | |
3230 | int cpu; | |
3231 | ||
3232 | /* only one dump */ | |
3233 | spin_lock_irqsave(&ftrace_dump_lock, flags); | |
3234 | if (dump_ran) | |
3235 | goto out; | |
3236 | ||
3237 | dump_ran = 1; | |
3238 | ||
3239 | /* No turning back! */ | |
3240 | ftrace_kill_atomic(); | |
3241 | ||
3242 | printk(KERN_TRACE "Dumping ftrace buffer:\n"); | |
3243 | ||
3244 | iter.tr = &global_trace; | |
3245 | iter.trace = current_trace; | |
3246 | ||
3247 | /* | |
3248 | * We need to stop all tracing on all CPUS to read the | |
3249 | * the next buffer. This is a bit expensive, but is | |
3250 | * not done often. We fill all what we can read, | |
3251 | * and then release the locks again. | |
3252 | */ | |
3253 | ||
3254 | cpus_clear(mask); | |
3255 | ||
3256 | for_each_tracing_cpu(cpu) { | |
3257 | data = iter.tr->data[cpu]; | |
3258 | ||
3259 | if (!head_page(data) || !data->trace_idx) | |
3260 | continue; | |
3261 | ||
3262 | atomic_inc(&data->disabled); | |
3263 | cpu_set(cpu, mask); | |
3264 | } | |
3265 | ||
3266 | for_each_cpu_mask(cpu, mask) { | |
3267 | data = iter.tr->data[cpu]; | |
3268 | __raw_spin_lock(&data->lock); | |
3269 | ||
3270 | if (data->overrun > iter.last_overrun[cpu]) | |
3271 | iter.overrun[cpu] += | |
3272 | data->overrun - iter.last_overrun[cpu]; | |
3273 | iter.last_overrun[cpu] = data->overrun; | |
3274 | } | |
3275 | ||
3276 | while (!trace_empty(&iter)) { | |
3277 | ||
3278 | if (!cnt) | |
3279 | printk(KERN_TRACE "---------------------------------\n"); | |
3280 | ||
3281 | cnt++; | |
3282 | ||
3283 | /* reset all but tr, trace, and overruns */ | |
3284 | memset(&iter.seq, 0, | |
3285 | sizeof(struct trace_iterator) - | |
3286 | offsetof(struct trace_iterator, seq)); | |
3287 | iter.iter_flags |= TRACE_FILE_LAT_FMT; | |
3288 | iter.pos = -1; | |
3289 | ||
3290 | if (find_next_entry_inc(&iter) != NULL) { | |
3291 | print_trace_line(&iter); | |
3292 | trace_consume(&iter); | |
3293 | } | |
3294 | ||
3295 | trace_printk_seq(&iter.seq); | |
3296 | } | |
3297 | ||
3298 | if (!cnt) | |
3299 | printk(KERN_TRACE " (ftrace buffer empty)\n"); | |
3300 | else | |
3301 | printk(KERN_TRACE "---------------------------------\n"); | |
3302 | ||
3303 | for_each_cpu_mask(cpu, mask) { | |
3304 | data = iter.tr->data[cpu]; | |
3305 | __raw_spin_unlock(&data->lock); | |
3306 | } | |
3307 | ||
3308 | for_each_cpu_mask(cpu, mask) { | |
3309 | data = iter.tr->data[cpu]; | |
3310 | atomic_dec(&data->disabled); | |
3311 | } | |
3312 | ||
3313 | ||
3314 | out: | |
3315 | spin_unlock_irqrestore(&ftrace_dump_lock, flags); | |
3316 | } | |
3317 | ||
4c11d7ae | 3318 | static int trace_alloc_page(void) |
bc0c38d1 | 3319 | { |
4c11d7ae | 3320 | struct trace_array_cpu *data; |
4c11d7ae SR |
3321 | struct page *page, *tmp; |
3322 | LIST_HEAD(pages); | |
c7aafc54 | 3323 | void *array; |
3eefae99 | 3324 | unsigned pages_allocated = 0; |
4c11d7ae SR |
3325 | int i; |
3326 | ||
3327 | /* first allocate a page for each CPU */ | |
ab46428c | 3328 | for_each_tracing_cpu(i) { |
4c11d7ae SR |
3329 | array = (void *)__get_free_page(GFP_KERNEL); |
3330 | if (array == NULL) { | |
3331 | printk(KERN_ERR "tracer: failed to allocate page" | |
3332 | "for trace buffer!\n"); | |
3333 | goto free_pages; | |
3334 | } | |
3335 | ||
3eefae99 | 3336 | pages_allocated++; |
4c11d7ae SR |
3337 | page = virt_to_page(array); |
3338 | list_add(&page->lru, &pages); | |
3339 | ||
3340 | /* Only allocate if we are actually using the max trace */ | |
3341 | #ifdef CONFIG_TRACER_MAX_TRACE | |
3342 | array = (void *)__get_free_page(GFP_KERNEL); | |
3343 | if (array == NULL) { | |
3344 | printk(KERN_ERR "tracer: failed to allocate page" | |
3345 | "for trace buffer!\n"); | |
3346 | goto free_pages; | |
3347 | } | |
3eefae99 | 3348 | pages_allocated++; |
4c11d7ae SR |
3349 | page = virt_to_page(array); |
3350 | list_add(&page->lru, &pages); | |
3351 | #endif | |
3352 | } | |
3353 | ||
3354 | /* Now that we successfully allocate a page per CPU, add them */ | |
ab46428c | 3355 | for_each_tracing_cpu(i) { |
4c11d7ae SR |
3356 | data = global_trace.data[i]; |
3357 | page = list_entry(pages.next, struct page, lru); | |
c7aafc54 | 3358 | list_del_init(&page->lru); |
4c11d7ae SR |
3359 | list_add_tail(&page->lru, &data->trace_pages); |
3360 | ClearPageLRU(page); | |
3361 | ||
3362 | #ifdef CONFIG_TRACER_MAX_TRACE | |
3363 | data = max_tr.data[i]; | |
3364 | page = list_entry(pages.next, struct page, lru); | |
c7aafc54 | 3365 | list_del_init(&page->lru); |
4c11d7ae SR |
3366 | list_add_tail(&page->lru, &data->trace_pages); |
3367 | SetPageLRU(page); | |
3368 | #endif | |
3369 | } | |
3eefae99 | 3370 | tracing_pages_allocated += pages_allocated; |
4c11d7ae SR |
3371 | global_trace.entries += ENTRIES_PER_PAGE; |
3372 | ||
3373 | return 0; | |
3374 | ||
3375 | free_pages: | |
3376 | list_for_each_entry_safe(page, tmp, &pages, lru) { | |
c7aafc54 | 3377 | list_del_init(&page->lru); |
4c11d7ae SR |
3378 | __free_page(page); |
3379 | } | |
3380 | return -ENOMEM; | |
bc0c38d1 SR |
3381 | } |
3382 | ||
a98a3c3f SR |
3383 | static int trace_free_page(void) |
3384 | { | |
3385 | struct trace_array_cpu *data; | |
3386 | struct page *page; | |
3387 | struct list_head *p; | |
3388 | int i; | |
3389 | int ret = 0; | |
3390 | ||
3391 | /* free one page from each buffer */ | |
ab46428c | 3392 | for_each_tracing_cpu(i) { |
a98a3c3f SR |
3393 | data = global_trace.data[i]; |
3394 | p = data->trace_pages.next; | |
3395 | if (p == &data->trace_pages) { | |
3396 | /* should never happen */ | |
3397 | WARN_ON(1); | |
3398 | tracing_disabled = 1; | |
3399 | ret = -1; | |
3400 | break; | |
3401 | } | |
3402 | page = list_entry(p, struct page, lru); | |
3403 | ClearPageLRU(page); | |
3404 | list_del(&page->lru); | |
3eefae99 SR |
3405 | tracing_pages_allocated--; |
3406 | tracing_pages_allocated--; | |
a98a3c3f SR |
3407 | __free_page(page); |
3408 | ||
3409 | tracing_reset(data); | |
3410 | ||
3411 | #ifdef CONFIG_TRACER_MAX_TRACE | |
3412 | data = max_tr.data[i]; | |
3413 | p = data->trace_pages.next; | |
3414 | if (p == &data->trace_pages) { | |
3415 | /* should never happen */ | |
3416 | WARN_ON(1); | |
3417 | tracing_disabled = 1; | |
3418 | ret = -1; | |
3419 | break; | |
3420 | } | |
3421 | page = list_entry(p, struct page, lru); | |
3422 | ClearPageLRU(page); | |
3423 | list_del(&page->lru); | |
3424 | __free_page(page); | |
3425 | ||
3426 | tracing_reset(data); | |
3427 | #endif | |
3428 | } | |
3429 | global_trace.entries -= ENTRIES_PER_PAGE; | |
3430 | ||
3431 | return ret; | |
3432 | } | |
3433 | ||
bc0c38d1 SR |
3434 | __init static int tracer_alloc_buffers(void) |
3435 | { | |
4c11d7ae SR |
3436 | struct trace_array_cpu *data; |
3437 | void *array; | |
3438 | struct page *page; | |
3439 | int pages = 0; | |
60a11774 | 3440 | int ret = -ENOMEM; |
bc0c38d1 SR |
3441 | int i; |
3442 | ||
ab46428c SR |
3443 | /* TODO: make the number of buffers hot pluggable with CPUS */ |
3444 | tracing_nr_buffers = num_possible_cpus(); | |
3445 | tracing_buffer_mask = cpu_possible_map; | |
3446 | ||
4c11d7ae | 3447 | /* Allocate the first page for all buffers */ |
ab46428c | 3448 | for_each_tracing_cpu(i) { |
4c11d7ae | 3449 | data = global_trace.data[i] = &per_cpu(global_trace_cpu, i); |
bc0c38d1 SR |
3450 | max_tr.data[i] = &per_cpu(max_data, i); |
3451 | ||
4c11d7ae | 3452 | array = (void *)__get_free_page(GFP_KERNEL); |
bc0c38d1 | 3453 | if (array == NULL) { |
4c11d7ae SR |
3454 | printk(KERN_ERR "tracer: failed to allocate page" |
3455 | "for trace buffer!\n"); | |
bc0c38d1 SR |
3456 | goto free_buffers; |
3457 | } | |
4c11d7ae SR |
3458 | |
3459 | /* set the array to the list */ | |
3460 | INIT_LIST_HEAD(&data->trace_pages); | |
3461 | page = virt_to_page(array); | |
3462 | list_add(&page->lru, &data->trace_pages); | |
3463 | /* use the LRU flag to differentiate the two buffers */ | |
3464 | ClearPageLRU(page); | |
bc0c38d1 | 3465 | |
a98a3c3f SR |
3466 | data->lock = (raw_spinlock_t)__RAW_SPIN_LOCK_UNLOCKED; |
3467 | max_tr.data[i]->lock = (raw_spinlock_t)__RAW_SPIN_LOCK_UNLOCKED; | |
3468 | ||
bc0c38d1 SR |
3469 | /* Only allocate if we are actually using the max trace */ |
3470 | #ifdef CONFIG_TRACER_MAX_TRACE | |
4c11d7ae | 3471 | array = (void *)__get_free_page(GFP_KERNEL); |
bc0c38d1 | 3472 | if (array == NULL) { |
4c11d7ae SR |
3473 | printk(KERN_ERR "tracer: failed to allocate page" |
3474 | "for trace buffer!\n"); | |
bc0c38d1 SR |
3475 | goto free_buffers; |
3476 | } | |
4c11d7ae SR |
3477 | |
3478 | INIT_LIST_HEAD(&max_tr.data[i]->trace_pages); | |
3479 | page = virt_to_page(array); | |
3480 | list_add(&page->lru, &max_tr.data[i]->trace_pages); | |
3481 | SetPageLRU(page); | |
bc0c38d1 SR |
3482 | #endif |
3483 | } | |
3484 | ||
3485 | /* | |
3486 | * Since we allocate by orders of pages, we may be able to | |
3487 | * round up a bit. | |
3488 | */ | |
4c11d7ae | 3489 | global_trace.entries = ENTRIES_PER_PAGE; |
4c11d7ae SR |
3490 | pages++; |
3491 | ||
3492 | while (global_trace.entries < trace_nr_entries) { | |
3493 | if (trace_alloc_page()) | |
3494 | break; | |
3495 | pages++; | |
3496 | } | |
89b2f978 | 3497 | max_tr.entries = global_trace.entries; |
bc0c38d1 | 3498 | |
20764ff1 JS |
3499 | pr_info("tracer: %d pages allocated for %ld entries of %ld bytes\n", |
3500 | pages, trace_nr_entries, (long)TRACE_ENTRY_SIZE); | |
bc0c38d1 SR |
3501 | pr_info(" actual entries %ld\n", global_trace.entries); |
3502 | ||
3503 | tracer_init_debugfs(); | |
3504 | ||
3505 | trace_init_cmdlines(); | |
3506 | ||
3507 | register_tracer(&no_tracer); | |
3508 | current_trace = &no_tracer; | |
3509 | ||
60a11774 | 3510 | /* All seems OK, enable tracing */ |
4902f884 | 3511 | global_trace.ctrl = tracer_enabled; |
60a11774 SR |
3512 | tracing_disabled = 0; |
3513 | ||
3f5a54e3 SR |
3514 | atomic_notifier_chain_register(&panic_notifier_list, |
3515 | &trace_panic_notifier); | |
3516 | ||
3517 | register_die_notifier(&trace_die_notifier); | |
3518 | ||
bc0c38d1 SR |
3519 | return 0; |
3520 | ||
3521 | free_buffers: | |
3522 | for (i-- ; i >= 0; i--) { | |
4c11d7ae | 3523 | struct page *page, *tmp; |
bc0c38d1 SR |
3524 | struct trace_array_cpu *data = global_trace.data[i]; |
3525 | ||
c7aafc54 | 3526 | if (data) { |
4c11d7ae SR |
3527 | list_for_each_entry_safe(page, tmp, |
3528 | &data->trace_pages, lru) { | |
c7aafc54 | 3529 | list_del_init(&page->lru); |
4c11d7ae SR |
3530 | __free_page(page); |
3531 | } | |
bc0c38d1 SR |
3532 | } |
3533 | ||
3534 | #ifdef CONFIG_TRACER_MAX_TRACE | |
3535 | data = max_tr.data[i]; | |
c7aafc54 | 3536 | if (data) { |
4c11d7ae SR |
3537 | list_for_each_entry_safe(page, tmp, |
3538 | &data->trace_pages, lru) { | |
c7aafc54 | 3539 | list_del_init(&page->lru); |
4c11d7ae SR |
3540 | __free_page(page); |
3541 | } | |
bc0c38d1 SR |
3542 | } |
3543 | #endif | |
3544 | } | |
60a11774 | 3545 | return ret; |
bc0c38d1 | 3546 | } |
60a11774 | 3547 | fs_initcall(tracer_alloc_buffers); |