Commit | Line | Data |
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bc0c38d1 SR |
1 | /* |
2 | * ring buffer based function tracer | |
3 | * | |
4 | * Copyright (C) 2007-2008 Steven Rostedt <srostedt@redhat.com> | |
5 | * Copyright (C) 2008 Ingo Molnar <mingo@redhat.com> | |
6 | * | |
7 | * Originally taken from the RT patch by: | |
8 | * Arnaldo Carvalho de Melo <acme@redhat.com> | |
9 | * | |
10 | * Based on code from the latency_tracer, that is: | |
11 | * Copyright (C) 2004-2006 Ingo Molnar | |
12 | * Copyright (C) 2004 William Lee Irwin III | |
13 | */ | |
14 | #include <linux/utsrelease.h> | |
15 | #include <linux/kallsyms.h> | |
16 | #include <linux/seq_file.h> | |
17 | #include <linux/debugfs.h> | |
4c11d7ae | 18 | #include <linux/pagemap.h> |
bc0c38d1 SR |
19 | #include <linux/hardirq.h> |
20 | #include <linux/linkage.h> | |
21 | #include <linux/uaccess.h> | |
22 | #include <linux/ftrace.h> | |
23 | #include <linux/module.h> | |
24 | #include <linux/percpu.h> | |
25 | #include <linux/ctype.h> | |
26 | #include <linux/init.h> | |
2a2cc8f7 | 27 | #include <linux/poll.h> |
bc0c38d1 SR |
28 | #include <linux/gfp.h> |
29 | #include <linux/fs.h> | |
3eefae99 | 30 | #include <linux/writeback.h> |
bc0c38d1 | 31 | |
86387f7e IM |
32 | #include <linux/stacktrace.h> |
33 | ||
bc0c38d1 SR |
34 | #include "trace.h" |
35 | ||
36 | unsigned long __read_mostly tracing_max_latency = (cycle_t)ULONG_MAX; | |
37 | unsigned long __read_mostly tracing_thresh; | |
38 | ||
ab46428c SR |
39 | static unsigned long __read_mostly tracing_nr_buffers; |
40 | static cpumask_t __read_mostly tracing_buffer_mask; | |
41 | ||
42 | #define for_each_tracing_cpu(cpu) \ | |
43 | for_each_cpu_mask(cpu, tracing_buffer_mask) | |
44 | ||
a98a3c3f | 45 | /* dummy trace to disable tracing */ |
cffae437 | 46 | static struct tracer no_tracer __read_mostly = { |
a98a3c3f SR |
47 | .name = "none", |
48 | }; | |
49 | ||
50 | static int trace_alloc_page(void); | |
51 | static int trace_free_page(void); | |
52 | ||
60a11774 SR |
53 | static int tracing_disabled = 1; |
54 | ||
3eefae99 SR |
55 | static unsigned long tracing_pages_allocated; |
56 | ||
72829bc3 | 57 | long |
bc0c38d1 SR |
58 | ns2usecs(cycle_t nsec) |
59 | { | |
60 | nsec += 500; | |
61 | do_div(nsec, 1000); | |
62 | return nsec; | |
63 | } | |
64 | ||
e309b41d | 65 | cycle_t ftrace_now(int cpu) |
750ed1a4 | 66 | { |
0fd9e0da | 67 | return cpu_clock(cpu); |
750ed1a4 IM |
68 | } |
69 | ||
4fcdae83 SR |
70 | /* |
71 | * The global_trace is the descriptor that holds the tracing | |
72 | * buffers for the live tracing. For each CPU, it contains | |
73 | * a link list of pages that will store trace entries. The | |
74 | * page descriptor of the pages in the memory is used to hold | |
75 | * the link list by linking the lru item in the page descriptor | |
76 | * to each of the pages in the buffer per CPU. | |
77 | * | |
78 | * For each active CPU there is a data field that holds the | |
79 | * pages for the buffer for that CPU. Each CPU has the same number | |
80 | * of pages allocated for its buffer. | |
81 | */ | |
bc0c38d1 SR |
82 | static struct trace_array global_trace; |
83 | ||
84 | static DEFINE_PER_CPU(struct trace_array_cpu, global_trace_cpu); | |
85 | ||
4fcdae83 SR |
86 | /* |
87 | * The max_tr is used to snapshot the global_trace when a maximum | |
88 | * latency is reached. Some tracers will use this to store a maximum | |
89 | * trace while it continues examining live traces. | |
90 | * | |
91 | * The buffers for the max_tr are set up the same as the global_trace. | |
92 | * When a snapshot is taken, the link list of the max_tr is swapped | |
93 | * with the link list of the global_trace and the buffers are reset for | |
94 | * the global_trace so the tracing can continue. | |
95 | */ | |
bc0c38d1 SR |
96 | static struct trace_array max_tr; |
97 | ||
98 | static DEFINE_PER_CPU(struct trace_array_cpu, max_data); | |
99 | ||
4fcdae83 | 100 | /* tracer_enabled is used to toggle activation of a tracer */ |
26994ead | 101 | static int tracer_enabled = 1; |
4fcdae83 SR |
102 | |
103 | /* | |
104 | * trace_nr_entries is the number of entries that is allocated | |
105 | * for a buffer. Note, the number of entries is always rounded | |
106 | * to ENTRIES_PER_PAGE. | |
107 | */ | |
57422797 | 108 | static unsigned long trace_nr_entries = 65536UL; |
bc0c38d1 | 109 | |
4fcdae83 | 110 | /* trace_types holds a link list of available tracers. */ |
bc0c38d1 | 111 | static struct tracer *trace_types __read_mostly; |
4fcdae83 SR |
112 | |
113 | /* current_trace points to the tracer that is currently active */ | |
bc0c38d1 | 114 | static struct tracer *current_trace __read_mostly; |
4fcdae83 SR |
115 | |
116 | /* | |
117 | * max_tracer_type_len is used to simplify the allocating of | |
118 | * buffers to read userspace tracer names. We keep track of | |
119 | * the longest tracer name registered. | |
120 | */ | |
bc0c38d1 SR |
121 | static int max_tracer_type_len; |
122 | ||
4fcdae83 SR |
123 | /* |
124 | * trace_types_lock is used to protect the trace_types list. | |
125 | * This lock is also used to keep user access serialized. | |
126 | * Accesses from userspace will grab this lock while userspace | |
127 | * activities happen inside the kernel. | |
128 | */ | |
bc0c38d1 | 129 | static DEFINE_MUTEX(trace_types_lock); |
4fcdae83 SR |
130 | |
131 | /* trace_wait is a waitqueue for tasks blocked on trace_poll */ | |
4e655519 IM |
132 | static DECLARE_WAIT_QUEUE_HEAD(trace_wait); |
133 | ||
4fcdae83 | 134 | /* trace_flags holds iter_ctrl options */ |
4e655519 IM |
135 | unsigned long trace_flags = TRACE_ITER_PRINT_PARENT; |
136 | ||
4fcdae83 SR |
137 | /** |
138 | * trace_wake_up - wake up tasks waiting for trace input | |
139 | * | |
140 | * Simply wakes up any task that is blocked on the trace_wait | |
141 | * queue. These is used with trace_poll for tasks polling the trace. | |
142 | */ | |
4e655519 IM |
143 | void trace_wake_up(void) |
144 | { | |
017730c1 IM |
145 | /* |
146 | * The runqueue_is_locked() can fail, but this is the best we | |
147 | * have for now: | |
148 | */ | |
149 | if (!(trace_flags & TRACE_ITER_BLOCK) && !runqueue_is_locked()) | |
4e655519 IM |
150 | wake_up(&trace_wait); |
151 | } | |
bc0c38d1 | 152 | |
4c11d7ae SR |
153 | #define ENTRIES_PER_PAGE (PAGE_SIZE / sizeof(struct trace_entry)) |
154 | ||
bc0c38d1 SR |
155 | static int __init set_nr_entries(char *str) |
156 | { | |
c6caeeb1 SR |
157 | unsigned long nr_entries; |
158 | int ret; | |
159 | ||
bc0c38d1 SR |
160 | if (!str) |
161 | return 0; | |
c6caeeb1 SR |
162 | ret = strict_strtoul(str, 0, &nr_entries); |
163 | /* nr_entries can not be zero */ | |
164 | if (ret < 0 || nr_entries == 0) | |
165 | return 0; | |
166 | trace_nr_entries = nr_entries; | |
bc0c38d1 SR |
167 | return 1; |
168 | } | |
169 | __setup("trace_entries=", set_nr_entries); | |
170 | ||
57f50be1 SR |
171 | unsigned long nsecs_to_usecs(unsigned long nsecs) |
172 | { | |
173 | return nsecs / 1000; | |
174 | } | |
175 | ||
4fcdae83 SR |
176 | /* |
177 | * trace_flag_type is an enumeration that holds different | |
178 | * states when a trace occurs. These are: | |
179 | * IRQS_OFF - interrupts were disabled | |
180 | * NEED_RESCED - reschedule is requested | |
181 | * HARDIRQ - inside an interrupt handler | |
182 | * SOFTIRQ - inside a softirq handler | |
183 | */ | |
bc0c38d1 SR |
184 | enum trace_flag_type { |
185 | TRACE_FLAG_IRQS_OFF = 0x01, | |
186 | TRACE_FLAG_NEED_RESCHED = 0x02, | |
187 | TRACE_FLAG_HARDIRQ = 0x04, | |
188 | TRACE_FLAG_SOFTIRQ = 0x08, | |
189 | }; | |
190 | ||
4fcdae83 SR |
191 | /* |
192 | * TRACE_ITER_SYM_MASK masks the options in trace_flags that | |
193 | * control the output of kernel symbols. | |
194 | */ | |
bc0c38d1 SR |
195 | #define TRACE_ITER_SYM_MASK \ |
196 | (TRACE_ITER_PRINT_PARENT|TRACE_ITER_SYM_OFFSET|TRACE_ITER_SYM_ADDR) | |
197 | ||
4fcdae83 | 198 | /* These must match the bit postions in trace_iterator_flags */ |
bc0c38d1 SR |
199 | static const char *trace_options[] = { |
200 | "print-parent", | |
201 | "sym-offset", | |
202 | "sym-addr", | |
203 | "verbose", | |
f9896bf3 | 204 | "raw", |
5e3ca0ec | 205 | "hex", |
cb0f12aa | 206 | "bin", |
2a2cc8f7 | 207 | "block", |
86387f7e | 208 | "stacktrace", |
4ac3ba41 | 209 | "sched-tree", |
bc0c38d1 SR |
210 | NULL |
211 | }; | |
212 | ||
4fcdae83 SR |
213 | /* |
214 | * ftrace_max_lock is used to protect the swapping of buffers | |
215 | * when taking a max snapshot. The buffers themselves are | |
216 | * protected by per_cpu spinlocks. But the action of the swap | |
217 | * needs its own lock. | |
218 | * | |
219 | * This is defined as a raw_spinlock_t in order to help | |
220 | * with performance when lockdep debugging is enabled. | |
221 | */ | |
92205c23 SR |
222 | static raw_spinlock_t ftrace_max_lock = |
223 | (raw_spinlock_t)__RAW_SPIN_LOCK_UNLOCKED; | |
bc0c38d1 SR |
224 | |
225 | /* | |
226 | * Copy the new maximum trace into the separate maximum-trace | |
227 | * structure. (this way the maximum trace is permanently saved, | |
228 | * for later retrieval via /debugfs/tracing/latency_trace) | |
229 | */ | |
e309b41d | 230 | static void |
bc0c38d1 SR |
231 | __update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) |
232 | { | |
233 | struct trace_array_cpu *data = tr->data[cpu]; | |
234 | ||
235 | max_tr.cpu = cpu; | |
236 | max_tr.time_start = data->preempt_timestamp; | |
237 | ||
238 | data = max_tr.data[cpu]; | |
239 | data->saved_latency = tracing_max_latency; | |
240 | ||
241 | memcpy(data->comm, tsk->comm, TASK_COMM_LEN); | |
242 | data->pid = tsk->pid; | |
243 | data->uid = tsk->uid; | |
244 | data->nice = tsk->static_prio - 20 - MAX_RT_PRIO; | |
245 | data->policy = tsk->policy; | |
246 | data->rt_priority = tsk->rt_priority; | |
247 | ||
248 | /* record this tasks comm */ | |
249 | tracing_record_cmdline(current); | |
250 | } | |
251 | ||
4fcdae83 SR |
252 | /** |
253 | * check_pages - integrity check of trace buffers | |
254 | * | |
255 | * As a safty measure we check to make sure the data pages have not | |
256 | * been corrupted. TODO: configure to disable this because it adds | |
257 | * a bit of overhead. | |
258 | */ | |
c7aafc54 IM |
259 | void check_pages(struct trace_array_cpu *data) |
260 | { | |
261 | struct page *page, *tmp; | |
262 | ||
263 | BUG_ON(data->trace_pages.next->prev != &data->trace_pages); | |
264 | BUG_ON(data->trace_pages.prev->next != &data->trace_pages); | |
265 | ||
266 | list_for_each_entry_safe(page, tmp, &data->trace_pages, lru) { | |
267 | BUG_ON(page->lru.next->prev != &page->lru); | |
268 | BUG_ON(page->lru.prev->next != &page->lru); | |
269 | } | |
270 | } | |
271 | ||
4fcdae83 SR |
272 | /** |
273 | * head_page - page address of the first page in per_cpu buffer. | |
274 | * | |
275 | * head_page returns the page address of the first page in | |
276 | * a per_cpu buffer. This also preforms various consistency | |
277 | * checks to make sure the buffer has not been corrupted. | |
278 | */ | |
c7aafc54 IM |
279 | void *head_page(struct trace_array_cpu *data) |
280 | { | |
281 | struct page *page; | |
282 | ||
283 | check_pages(data); | |
284 | if (list_empty(&data->trace_pages)) | |
285 | return NULL; | |
286 | ||
287 | page = list_entry(data->trace_pages.next, struct page, lru); | |
288 | BUG_ON(&page->lru == &data->trace_pages); | |
289 | ||
290 | return page_address(page); | |
291 | } | |
292 | ||
4fcdae83 SR |
293 | /** |
294 | * trace_seq_printf - sequence printing of trace information | |
295 | * @s: trace sequence descriptor | |
296 | * @fmt: printf format string | |
297 | * | |
298 | * The tracer may use either sequence operations or its own | |
299 | * copy to user routines. To simplify formating of a trace | |
300 | * trace_seq_printf is used to store strings into a special | |
301 | * buffer (@s). Then the output may be either used by | |
302 | * the sequencer or pulled into another buffer. | |
303 | */ | |
72829bc3 | 304 | int |
214023c3 SR |
305 | trace_seq_printf(struct trace_seq *s, const char *fmt, ...) |
306 | { | |
307 | int len = (PAGE_SIZE - 1) - s->len; | |
308 | va_list ap; | |
b3806b43 | 309 | int ret; |
214023c3 SR |
310 | |
311 | if (!len) | |
312 | return 0; | |
313 | ||
314 | va_start(ap, fmt); | |
b3806b43 | 315 | ret = vsnprintf(s->buffer + s->len, len, fmt, ap); |
214023c3 SR |
316 | va_end(ap); |
317 | ||
b3806b43 | 318 | /* If we can't write it all, don't bother writing anything */ |
72829bc3 | 319 | if (ret >= len) |
b3806b43 SR |
320 | return 0; |
321 | ||
322 | s->len += ret; | |
214023c3 SR |
323 | |
324 | return len; | |
325 | } | |
326 | ||
4fcdae83 SR |
327 | /** |
328 | * trace_seq_puts - trace sequence printing of simple string | |
329 | * @s: trace sequence descriptor | |
330 | * @str: simple string to record | |
331 | * | |
332 | * The tracer may use either the sequence operations or its own | |
333 | * copy to user routines. This function records a simple string | |
334 | * into a special buffer (@s) for later retrieval by a sequencer | |
335 | * or other mechanism. | |
336 | */ | |
e309b41d | 337 | static int |
214023c3 SR |
338 | trace_seq_puts(struct trace_seq *s, const char *str) |
339 | { | |
340 | int len = strlen(str); | |
341 | ||
342 | if (len > ((PAGE_SIZE - 1) - s->len)) | |
b3806b43 | 343 | return 0; |
214023c3 SR |
344 | |
345 | memcpy(s->buffer + s->len, str, len); | |
346 | s->len += len; | |
347 | ||
348 | return len; | |
349 | } | |
350 | ||
e309b41d | 351 | static int |
214023c3 SR |
352 | trace_seq_putc(struct trace_seq *s, unsigned char c) |
353 | { | |
354 | if (s->len >= (PAGE_SIZE - 1)) | |
355 | return 0; | |
356 | ||
357 | s->buffer[s->len++] = c; | |
358 | ||
359 | return 1; | |
360 | } | |
361 | ||
e309b41d | 362 | static int |
cb0f12aa IM |
363 | trace_seq_putmem(struct trace_seq *s, void *mem, size_t len) |
364 | { | |
365 | if (len > ((PAGE_SIZE - 1) - s->len)) | |
366 | return 0; | |
367 | ||
368 | memcpy(s->buffer + s->len, mem, len); | |
369 | s->len += len; | |
370 | ||
371 | return len; | |
372 | } | |
373 | ||
5e3ca0ec | 374 | #define HEX_CHARS 17 |
93dcc6ea | 375 | static const char hex2asc[] = "0123456789abcdef"; |
5e3ca0ec | 376 | |
e309b41d | 377 | static int |
5e3ca0ec IM |
378 | trace_seq_putmem_hex(struct trace_seq *s, void *mem, size_t len) |
379 | { | |
380 | unsigned char hex[HEX_CHARS]; | |
93dcc6ea | 381 | unsigned char *data = mem; |
5e3ca0ec IM |
382 | unsigned char byte; |
383 | int i, j; | |
384 | ||
385 | BUG_ON(len >= HEX_CHARS); | |
386 | ||
5e3ca0ec IM |
387 | #ifdef __BIG_ENDIAN |
388 | for (i = 0, j = 0; i < len; i++) { | |
389 | #else | |
390 | for (i = len-1, j = 0; i >= 0; i--) { | |
391 | #endif | |
392 | byte = data[i]; | |
393 | ||
93dcc6ea TG |
394 | hex[j++] = hex2asc[byte & 0x0f]; |
395 | hex[j++] = hex2asc[byte >> 4]; | |
5e3ca0ec | 396 | } |
93dcc6ea | 397 | hex[j++] = ' '; |
5e3ca0ec IM |
398 | |
399 | return trace_seq_putmem(s, hex, j); | |
400 | } | |
401 | ||
e309b41d | 402 | static void |
214023c3 SR |
403 | trace_seq_reset(struct trace_seq *s) |
404 | { | |
405 | s->len = 0; | |
6c6c2796 PP |
406 | s->readpos = 0; |
407 | } | |
408 | ||
409 | ssize_t trace_seq_to_user(struct trace_seq *s, char __user *ubuf, size_t cnt) | |
410 | { | |
411 | int len; | |
412 | int ret; | |
413 | ||
414 | if (s->len <= s->readpos) | |
415 | return -EBUSY; | |
416 | ||
417 | len = s->len - s->readpos; | |
418 | if (cnt > len) | |
419 | cnt = len; | |
420 | ret = copy_to_user(ubuf, s->buffer + s->readpos, cnt); | |
421 | if (ret) | |
422 | return -EFAULT; | |
423 | ||
424 | s->readpos += len; | |
425 | return cnt; | |
214023c3 SR |
426 | } |
427 | ||
e309b41d | 428 | static void |
214023c3 SR |
429 | trace_print_seq(struct seq_file *m, struct trace_seq *s) |
430 | { | |
431 | int len = s->len >= PAGE_SIZE ? PAGE_SIZE - 1 : s->len; | |
432 | ||
433 | s->buffer[len] = 0; | |
434 | seq_puts(m, s->buffer); | |
435 | ||
436 | trace_seq_reset(s); | |
437 | } | |
438 | ||
4fcdae83 SR |
439 | /* |
440 | * flip the trace buffers between two trace descriptors. | |
441 | * This usually is the buffers between the global_trace and | |
442 | * the max_tr to record a snapshot of a current trace. | |
443 | * | |
444 | * The ftrace_max_lock must be held. | |
445 | */ | |
e309b41d | 446 | static void |
c7aafc54 IM |
447 | flip_trace(struct trace_array_cpu *tr1, struct trace_array_cpu *tr2) |
448 | { | |
449 | struct list_head flip_pages; | |
450 | ||
451 | INIT_LIST_HEAD(&flip_pages); | |
452 | ||
93a588f4 | 453 | memcpy(&tr1->trace_head_idx, &tr2->trace_head_idx, |
c7aafc54 | 454 | sizeof(struct trace_array_cpu) - |
93a588f4 | 455 | offsetof(struct trace_array_cpu, trace_head_idx)); |
c7aafc54 IM |
456 | |
457 | check_pages(tr1); | |
458 | check_pages(tr2); | |
459 | list_splice_init(&tr1->trace_pages, &flip_pages); | |
460 | list_splice_init(&tr2->trace_pages, &tr1->trace_pages); | |
461 | list_splice_init(&flip_pages, &tr2->trace_pages); | |
462 | BUG_ON(!list_empty(&flip_pages)); | |
463 | check_pages(tr1); | |
464 | check_pages(tr2); | |
465 | } | |
466 | ||
4fcdae83 SR |
467 | /** |
468 | * update_max_tr - snapshot all trace buffers from global_trace to max_tr | |
469 | * @tr: tracer | |
470 | * @tsk: the task with the latency | |
471 | * @cpu: The cpu that initiated the trace. | |
472 | * | |
473 | * Flip the buffers between the @tr and the max_tr and record information | |
474 | * about which task was the cause of this latency. | |
475 | */ | |
e309b41d | 476 | void |
bc0c38d1 SR |
477 | update_max_tr(struct trace_array *tr, struct task_struct *tsk, int cpu) |
478 | { | |
479 | struct trace_array_cpu *data; | |
bc0c38d1 SR |
480 | int i; |
481 | ||
4c11d7ae | 482 | WARN_ON_ONCE(!irqs_disabled()); |
92205c23 | 483 | __raw_spin_lock(&ftrace_max_lock); |
bc0c38d1 | 484 | /* clear out all the previous traces */ |
ab46428c | 485 | for_each_tracing_cpu(i) { |
bc0c38d1 | 486 | data = tr->data[i]; |
c7aafc54 | 487 | flip_trace(max_tr.data[i], data); |
89b2f978 | 488 | tracing_reset(data); |
bc0c38d1 SR |
489 | } |
490 | ||
491 | __update_max_tr(tr, tsk, cpu); | |
92205c23 | 492 | __raw_spin_unlock(&ftrace_max_lock); |
bc0c38d1 SR |
493 | } |
494 | ||
495 | /** | |
496 | * update_max_tr_single - only copy one trace over, and reset the rest | |
497 | * @tr - tracer | |
498 | * @tsk - task with the latency | |
499 | * @cpu - the cpu of the buffer to copy. | |
4fcdae83 SR |
500 | * |
501 | * Flip the trace of a single CPU buffer between the @tr and the max_tr. | |
bc0c38d1 | 502 | */ |
e309b41d | 503 | void |
bc0c38d1 SR |
504 | update_max_tr_single(struct trace_array *tr, struct task_struct *tsk, int cpu) |
505 | { | |
506 | struct trace_array_cpu *data = tr->data[cpu]; | |
bc0c38d1 SR |
507 | int i; |
508 | ||
4c11d7ae | 509 | WARN_ON_ONCE(!irqs_disabled()); |
92205c23 | 510 | __raw_spin_lock(&ftrace_max_lock); |
ab46428c | 511 | for_each_tracing_cpu(i) |
bc0c38d1 SR |
512 | tracing_reset(max_tr.data[i]); |
513 | ||
c7aafc54 | 514 | flip_trace(max_tr.data[cpu], data); |
89b2f978 | 515 | tracing_reset(data); |
bc0c38d1 SR |
516 | |
517 | __update_max_tr(tr, tsk, cpu); | |
92205c23 | 518 | __raw_spin_unlock(&ftrace_max_lock); |
bc0c38d1 SR |
519 | } |
520 | ||
4fcdae83 SR |
521 | /** |
522 | * register_tracer - register a tracer with the ftrace system. | |
523 | * @type - the plugin for the tracer | |
524 | * | |
525 | * Register a new plugin tracer. | |
526 | */ | |
bc0c38d1 SR |
527 | int register_tracer(struct tracer *type) |
528 | { | |
529 | struct tracer *t; | |
530 | int len; | |
531 | int ret = 0; | |
532 | ||
533 | if (!type->name) { | |
534 | pr_info("Tracer must have a name\n"); | |
535 | return -1; | |
536 | } | |
537 | ||
538 | mutex_lock(&trace_types_lock); | |
539 | for (t = trace_types; t; t = t->next) { | |
540 | if (strcmp(type->name, t->name) == 0) { | |
541 | /* already found */ | |
542 | pr_info("Trace %s already registered\n", | |
543 | type->name); | |
544 | ret = -1; | |
545 | goto out; | |
546 | } | |
547 | } | |
548 | ||
60a11774 SR |
549 | #ifdef CONFIG_FTRACE_STARTUP_TEST |
550 | if (type->selftest) { | |
551 | struct tracer *saved_tracer = current_trace; | |
552 | struct trace_array_cpu *data; | |
553 | struct trace_array *tr = &global_trace; | |
554 | int saved_ctrl = tr->ctrl; | |
555 | int i; | |
556 | /* | |
557 | * Run a selftest on this tracer. | |
558 | * Here we reset the trace buffer, and set the current | |
559 | * tracer to be this tracer. The tracer can then run some | |
560 | * internal tracing to verify that everything is in order. | |
561 | * If we fail, we do not register this tracer. | |
562 | */ | |
ab46428c | 563 | for_each_tracing_cpu(i) { |
60a11774 | 564 | data = tr->data[i]; |
c7aafc54 IM |
565 | if (!head_page(data)) |
566 | continue; | |
60a11774 SR |
567 | tracing_reset(data); |
568 | } | |
569 | current_trace = type; | |
570 | tr->ctrl = 0; | |
571 | /* the test is responsible for initializing and enabling */ | |
572 | pr_info("Testing tracer %s: ", type->name); | |
573 | ret = type->selftest(type, tr); | |
574 | /* the test is responsible for resetting too */ | |
575 | current_trace = saved_tracer; | |
576 | tr->ctrl = saved_ctrl; | |
577 | if (ret) { | |
578 | printk(KERN_CONT "FAILED!\n"); | |
579 | goto out; | |
580 | } | |
1d4db00a | 581 | /* Only reset on passing, to avoid touching corrupted buffers */ |
ab46428c | 582 | for_each_tracing_cpu(i) { |
1d4db00a SR |
583 | data = tr->data[i]; |
584 | if (!head_page(data)) | |
585 | continue; | |
586 | tracing_reset(data); | |
587 | } | |
60a11774 SR |
588 | printk(KERN_CONT "PASSED\n"); |
589 | } | |
590 | #endif | |
591 | ||
bc0c38d1 SR |
592 | type->next = trace_types; |
593 | trace_types = type; | |
594 | len = strlen(type->name); | |
595 | if (len > max_tracer_type_len) | |
596 | max_tracer_type_len = len; | |
60a11774 | 597 | |
bc0c38d1 SR |
598 | out: |
599 | mutex_unlock(&trace_types_lock); | |
600 | ||
601 | return ret; | |
602 | } | |
603 | ||
604 | void unregister_tracer(struct tracer *type) | |
605 | { | |
606 | struct tracer **t; | |
607 | int len; | |
608 | ||
609 | mutex_lock(&trace_types_lock); | |
610 | for (t = &trace_types; *t; t = &(*t)->next) { | |
611 | if (*t == type) | |
612 | goto found; | |
613 | } | |
614 | pr_info("Trace %s not registered\n", type->name); | |
615 | goto out; | |
616 | ||
617 | found: | |
618 | *t = (*t)->next; | |
619 | if (strlen(type->name) != max_tracer_type_len) | |
620 | goto out; | |
621 | ||
622 | max_tracer_type_len = 0; | |
623 | for (t = &trace_types; *t; t = &(*t)->next) { | |
624 | len = strlen((*t)->name); | |
625 | if (len > max_tracer_type_len) | |
626 | max_tracer_type_len = len; | |
627 | } | |
628 | out: | |
629 | mutex_unlock(&trace_types_lock); | |
630 | } | |
631 | ||
e309b41d | 632 | void tracing_reset(struct trace_array_cpu *data) |
bc0c38d1 SR |
633 | { |
634 | data->trace_idx = 0; | |
53d0aa77 | 635 | data->overrun = 0; |
93a588f4 SR |
636 | data->trace_head = data->trace_tail = head_page(data); |
637 | data->trace_head_idx = 0; | |
638 | data->trace_tail_idx = 0; | |
bc0c38d1 SR |
639 | } |
640 | ||
bc0c38d1 SR |
641 | #define SAVED_CMDLINES 128 |
642 | static unsigned map_pid_to_cmdline[PID_MAX_DEFAULT+1]; | |
643 | static unsigned map_cmdline_to_pid[SAVED_CMDLINES]; | |
644 | static char saved_cmdlines[SAVED_CMDLINES][TASK_COMM_LEN]; | |
645 | static int cmdline_idx; | |
646 | static DEFINE_SPINLOCK(trace_cmdline_lock); | |
25b0b44a SR |
647 | |
648 | /* trace in all context switches */ | |
649 | atomic_t trace_record_cmdline_enabled __read_mostly; | |
650 | ||
651 | /* temporary disable recording */ | |
652 | atomic_t trace_record_cmdline_disabled __read_mostly; | |
bc0c38d1 SR |
653 | |
654 | static void trace_init_cmdlines(void) | |
655 | { | |
656 | memset(&map_pid_to_cmdline, -1, sizeof(map_pid_to_cmdline)); | |
657 | memset(&map_cmdline_to_pid, -1, sizeof(map_cmdline_to_pid)); | |
658 | cmdline_idx = 0; | |
659 | } | |
660 | ||
e309b41d | 661 | void trace_stop_cmdline_recording(void); |
bc0c38d1 | 662 | |
e309b41d | 663 | static void trace_save_cmdline(struct task_struct *tsk) |
bc0c38d1 SR |
664 | { |
665 | unsigned map; | |
666 | unsigned idx; | |
667 | ||
668 | if (!tsk->pid || unlikely(tsk->pid > PID_MAX_DEFAULT)) | |
669 | return; | |
670 | ||
671 | /* | |
672 | * It's not the end of the world if we don't get | |
673 | * the lock, but we also don't want to spin | |
674 | * nor do we want to disable interrupts, | |
675 | * so if we miss here, then better luck next time. | |
676 | */ | |
677 | if (!spin_trylock(&trace_cmdline_lock)) | |
678 | return; | |
679 | ||
680 | idx = map_pid_to_cmdline[tsk->pid]; | |
681 | if (idx >= SAVED_CMDLINES) { | |
682 | idx = (cmdline_idx + 1) % SAVED_CMDLINES; | |
683 | ||
684 | map = map_cmdline_to_pid[idx]; | |
685 | if (map <= PID_MAX_DEFAULT) | |
686 | map_pid_to_cmdline[map] = (unsigned)-1; | |
687 | ||
688 | map_pid_to_cmdline[tsk->pid] = idx; | |
689 | ||
690 | cmdline_idx = idx; | |
691 | } | |
692 | ||
693 | memcpy(&saved_cmdlines[idx], tsk->comm, TASK_COMM_LEN); | |
694 | ||
695 | spin_unlock(&trace_cmdline_lock); | |
696 | } | |
697 | ||
e309b41d | 698 | static char *trace_find_cmdline(int pid) |
bc0c38d1 SR |
699 | { |
700 | char *cmdline = "<...>"; | |
701 | unsigned map; | |
702 | ||
703 | if (!pid) | |
704 | return "<idle>"; | |
705 | ||
706 | if (pid > PID_MAX_DEFAULT) | |
707 | goto out; | |
708 | ||
709 | map = map_pid_to_cmdline[pid]; | |
710 | if (map >= SAVED_CMDLINES) | |
711 | goto out; | |
712 | ||
713 | cmdline = saved_cmdlines[map]; | |
714 | ||
715 | out: | |
716 | return cmdline; | |
717 | } | |
718 | ||
e309b41d | 719 | void tracing_record_cmdline(struct task_struct *tsk) |
bc0c38d1 SR |
720 | { |
721 | if (atomic_read(&trace_record_cmdline_disabled)) | |
722 | return; | |
723 | ||
724 | trace_save_cmdline(tsk); | |
725 | } | |
726 | ||
e309b41d | 727 | static inline struct list_head * |
93a588f4 SR |
728 | trace_next_list(struct trace_array_cpu *data, struct list_head *next) |
729 | { | |
730 | /* | |
731 | * Roundrobin - but skip the head (which is not a real page): | |
732 | */ | |
733 | next = next->next; | |
734 | if (unlikely(next == &data->trace_pages)) | |
735 | next = next->next; | |
736 | BUG_ON(next == &data->trace_pages); | |
737 | ||
738 | return next; | |
739 | } | |
740 | ||
e309b41d | 741 | static inline void * |
93a588f4 SR |
742 | trace_next_page(struct trace_array_cpu *data, void *addr) |
743 | { | |
744 | struct list_head *next; | |
745 | struct page *page; | |
746 | ||
747 | page = virt_to_page(addr); | |
748 | ||
749 | next = trace_next_list(data, &page->lru); | |
750 | page = list_entry(next, struct page, lru); | |
751 | ||
752 | return page_address(page); | |
753 | } | |
754 | ||
e309b41d | 755 | static inline struct trace_entry * |
c7aafc54 | 756 | tracing_get_trace_entry(struct trace_array *tr, struct trace_array_cpu *data) |
bc0c38d1 SR |
757 | { |
758 | unsigned long idx, idx_next; | |
759 | struct trace_entry *entry; | |
760 | ||
4c11d7ae | 761 | data->trace_idx++; |
93a588f4 | 762 | idx = data->trace_head_idx; |
bc0c38d1 SR |
763 | idx_next = idx + 1; |
764 | ||
c7aafc54 IM |
765 | BUG_ON(idx * TRACE_ENTRY_SIZE >= PAGE_SIZE); |
766 | ||
93a588f4 | 767 | entry = data->trace_head + idx * TRACE_ENTRY_SIZE; |
4c11d7ae SR |
768 | |
769 | if (unlikely(idx_next >= ENTRIES_PER_PAGE)) { | |
93a588f4 | 770 | data->trace_head = trace_next_page(data, data->trace_head); |
bc0c38d1 SR |
771 | idx_next = 0; |
772 | } | |
773 | ||
93a588f4 SR |
774 | if (data->trace_head == data->trace_tail && |
775 | idx_next == data->trace_tail_idx) { | |
776 | /* overrun */ | |
53d0aa77 | 777 | data->overrun++; |
93a588f4 SR |
778 | data->trace_tail_idx++; |
779 | if (data->trace_tail_idx >= ENTRIES_PER_PAGE) { | |
780 | data->trace_tail = | |
781 | trace_next_page(data, data->trace_tail); | |
782 | data->trace_tail_idx = 0; | |
783 | } | |
784 | } | |
785 | ||
786 | data->trace_head_idx = idx_next; | |
bc0c38d1 SR |
787 | |
788 | return entry; | |
789 | } | |
790 | ||
e309b41d | 791 | static inline void |
c7aafc54 | 792 | tracing_generic_entry_update(struct trace_entry *entry, unsigned long flags) |
bc0c38d1 SR |
793 | { |
794 | struct task_struct *tsk = current; | |
795 | unsigned long pc; | |
796 | ||
797 | pc = preempt_count(); | |
798 | ||
c7aafc54 | 799 | entry->preempt_count = pc & 0xff; |
72829bc3 | 800 | entry->pid = (tsk) ? tsk->pid : 0; |
750ed1a4 | 801 | entry->t = ftrace_now(raw_smp_processor_id()); |
bc0c38d1 SR |
802 | entry->flags = (irqs_disabled_flags(flags) ? TRACE_FLAG_IRQS_OFF : 0) | |
803 | ((pc & HARDIRQ_MASK) ? TRACE_FLAG_HARDIRQ : 0) | | |
804 | ((pc & SOFTIRQ_MASK) ? TRACE_FLAG_SOFTIRQ : 0) | | |
805 | (need_resched() ? TRACE_FLAG_NEED_RESCHED : 0); | |
806 | } | |
807 | ||
e309b41d | 808 | void |
6fb44b71 SR |
809 | trace_function(struct trace_array *tr, struct trace_array_cpu *data, |
810 | unsigned long ip, unsigned long parent_ip, unsigned long flags) | |
bc0c38d1 SR |
811 | { |
812 | struct trace_entry *entry; | |
dcb6308f | 813 | unsigned long irq_flags; |
bc0c38d1 | 814 | |
92205c23 SR |
815 | raw_local_irq_save(irq_flags); |
816 | __raw_spin_lock(&data->lock); | |
c7aafc54 | 817 | entry = tracing_get_trace_entry(tr, data); |
bc0c38d1 | 818 | tracing_generic_entry_update(entry, flags); |
c7aafc54 IM |
819 | entry->type = TRACE_FN; |
820 | entry->fn.ip = ip; | |
821 | entry->fn.parent_ip = parent_ip; | |
92205c23 SR |
822 | __raw_spin_unlock(&data->lock); |
823 | raw_local_irq_restore(irq_flags); | |
bc0c38d1 SR |
824 | } |
825 | ||
e309b41d | 826 | void |
2e0f5761 IM |
827 | ftrace(struct trace_array *tr, struct trace_array_cpu *data, |
828 | unsigned long ip, unsigned long parent_ip, unsigned long flags) | |
829 | { | |
830 | if (likely(!atomic_read(&data->disabled))) | |
6fb44b71 | 831 | trace_function(tr, data, ip, parent_ip, flags); |
2e0f5761 IM |
832 | } |
833 | ||
86387f7e IM |
834 | void __trace_stack(struct trace_array *tr, |
835 | struct trace_array_cpu *data, | |
836 | unsigned long flags, | |
837 | int skip) | |
838 | { | |
839 | struct trace_entry *entry; | |
840 | struct stack_trace trace; | |
841 | ||
842 | if (!(trace_flags & TRACE_ITER_STACKTRACE)) | |
843 | return; | |
844 | ||
845 | entry = tracing_get_trace_entry(tr, data); | |
846 | tracing_generic_entry_update(entry, flags); | |
847 | entry->type = TRACE_STACK; | |
848 | ||
849 | memset(&entry->stack, 0, sizeof(entry->stack)); | |
850 | ||
851 | trace.nr_entries = 0; | |
852 | trace.max_entries = FTRACE_STACK_ENTRIES; | |
853 | trace.skip = skip; | |
854 | trace.entries = entry->stack.caller; | |
855 | ||
856 | save_stack_trace(&trace); | |
f0a920d5 IM |
857 | } |
858 | ||
a4feb834 IM |
859 | void |
860 | __trace_special(void *__tr, void *__data, | |
861 | unsigned long arg1, unsigned long arg2, unsigned long arg3) | |
862 | { | |
863 | struct trace_array_cpu *data = __data; | |
864 | struct trace_array *tr = __tr; | |
865 | struct trace_entry *entry; | |
866 | unsigned long irq_flags; | |
867 | ||
868 | raw_local_irq_save(irq_flags); | |
869 | __raw_spin_lock(&data->lock); | |
870 | entry = tracing_get_trace_entry(tr, data); | |
871 | tracing_generic_entry_update(entry, 0); | |
872 | entry->type = TRACE_SPECIAL; | |
873 | entry->special.arg1 = arg1; | |
874 | entry->special.arg2 = arg2; | |
875 | entry->special.arg3 = arg3; | |
876 | __trace_stack(tr, data, irq_flags, 4); | |
877 | __raw_spin_unlock(&data->lock); | |
878 | raw_local_irq_restore(irq_flags); | |
879 | ||
880 | trace_wake_up(); | |
881 | } | |
882 | ||
e309b41d | 883 | void |
bc0c38d1 SR |
884 | tracing_sched_switch_trace(struct trace_array *tr, |
885 | struct trace_array_cpu *data, | |
86387f7e IM |
886 | struct task_struct *prev, |
887 | struct task_struct *next, | |
bc0c38d1 SR |
888 | unsigned long flags) |
889 | { | |
890 | struct trace_entry *entry; | |
dcb6308f | 891 | unsigned long irq_flags; |
bc0c38d1 | 892 | |
92205c23 SR |
893 | raw_local_irq_save(irq_flags); |
894 | __raw_spin_lock(&data->lock); | |
c7aafc54 | 895 | entry = tracing_get_trace_entry(tr, data); |
bc0c38d1 SR |
896 | tracing_generic_entry_update(entry, flags); |
897 | entry->type = TRACE_CTX; | |
898 | entry->ctx.prev_pid = prev->pid; | |
899 | entry->ctx.prev_prio = prev->prio; | |
900 | entry->ctx.prev_state = prev->state; | |
901 | entry->ctx.next_pid = next->pid; | |
902 | entry->ctx.next_prio = next->prio; | |
bac524d3 | 903 | entry->ctx.next_state = next->state; |
74f4e369 | 904 | __trace_stack(tr, data, flags, 5); |
92205c23 SR |
905 | __raw_spin_unlock(&data->lock); |
906 | raw_local_irq_restore(irq_flags); | |
bc0c38d1 SR |
907 | } |
908 | ||
57422797 IM |
909 | void |
910 | tracing_sched_wakeup_trace(struct trace_array *tr, | |
911 | struct trace_array_cpu *data, | |
86387f7e IM |
912 | struct task_struct *wakee, |
913 | struct task_struct *curr, | |
57422797 IM |
914 | unsigned long flags) |
915 | { | |
916 | struct trace_entry *entry; | |
917 | unsigned long irq_flags; | |
918 | ||
92205c23 SR |
919 | raw_local_irq_save(irq_flags); |
920 | __raw_spin_lock(&data->lock); | |
57422797 IM |
921 | entry = tracing_get_trace_entry(tr, data); |
922 | tracing_generic_entry_update(entry, flags); | |
923 | entry->type = TRACE_WAKE; | |
924 | entry->ctx.prev_pid = curr->pid; | |
925 | entry->ctx.prev_prio = curr->prio; | |
926 | entry->ctx.prev_state = curr->state; | |
927 | entry->ctx.next_pid = wakee->pid; | |
928 | entry->ctx.next_prio = wakee->prio; | |
bac524d3 | 929 | entry->ctx.next_state = wakee->state; |
74f4e369 | 930 | __trace_stack(tr, data, flags, 6); |
92205c23 SR |
931 | __raw_spin_unlock(&data->lock); |
932 | raw_local_irq_restore(irq_flags); | |
017730c1 IM |
933 | |
934 | trace_wake_up(); | |
57422797 IM |
935 | } |
936 | ||
2e0f5761 | 937 | #ifdef CONFIG_FTRACE |
e309b41d | 938 | static void |
2e0f5761 IM |
939 | function_trace_call(unsigned long ip, unsigned long parent_ip) |
940 | { | |
941 | struct trace_array *tr = &global_trace; | |
942 | struct trace_array_cpu *data; | |
943 | unsigned long flags; | |
944 | long disabled; | |
945 | int cpu; | |
946 | ||
947 | if (unlikely(!tracer_enabled)) | |
948 | return; | |
949 | ||
950 | local_irq_save(flags); | |
951 | cpu = raw_smp_processor_id(); | |
952 | data = tr->data[cpu]; | |
953 | disabled = atomic_inc_return(&data->disabled); | |
954 | ||
955 | if (likely(disabled == 1)) | |
6fb44b71 | 956 | trace_function(tr, data, ip, parent_ip, flags); |
2e0f5761 IM |
957 | |
958 | atomic_dec(&data->disabled); | |
959 | local_irq_restore(flags); | |
960 | } | |
961 | ||
962 | static struct ftrace_ops trace_ops __read_mostly = | |
963 | { | |
964 | .func = function_trace_call, | |
965 | }; | |
966 | ||
e309b41d | 967 | void tracing_start_function_trace(void) |
2e0f5761 IM |
968 | { |
969 | register_ftrace_function(&trace_ops); | |
970 | } | |
971 | ||
e309b41d | 972 | void tracing_stop_function_trace(void) |
2e0f5761 IM |
973 | { |
974 | unregister_ftrace_function(&trace_ops); | |
975 | } | |
976 | #endif | |
977 | ||
bc0c38d1 SR |
978 | enum trace_file_type { |
979 | TRACE_FILE_LAT_FMT = 1, | |
980 | }; | |
981 | ||
982 | static struct trace_entry * | |
4c11d7ae SR |
983 | trace_entry_idx(struct trace_array *tr, struct trace_array_cpu *data, |
984 | struct trace_iterator *iter, int cpu) | |
bc0c38d1 | 985 | { |
4c11d7ae SR |
986 | struct page *page; |
987 | struct trace_entry *array; | |
bc0c38d1 | 988 | |
4c11d7ae | 989 | if (iter->next_idx[cpu] >= tr->entries || |
b3806b43 SR |
990 | iter->next_idx[cpu] >= data->trace_idx || |
991 | (data->trace_head == data->trace_tail && | |
992 | data->trace_head_idx == data->trace_tail_idx)) | |
bc0c38d1 SR |
993 | return NULL; |
994 | ||
4c11d7ae | 995 | if (!iter->next_page[cpu]) { |
93a588f4 SR |
996 | /* Initialize the iterator for this cpu trace buffer */ |
997 | WARN_ON(!data->trace_tail); | |
998 | page = virt_to_page(data->trace_tail); | |
999 | iter->next_page[cpu] = &page->lru; | |
1000 | iter->next_page_idx[cpu] = data->trace_tail_idx; | |
4c11d7ae | 1001 | } |
bc0c38d1 | 1002 | |
4c11d7ae | 1003 | page = list_entry(iter->next_page[cpu], struct page, lru); |
c7aafc54 IM |
1004 | BUG_ON(&data->trace_pages == &page->lru); |
1005 | ||
4c11d7ae SR |
1006 | array = page_address(page); |
1007 | ||
93a588f4 | 1008 | WARN_ON(iter->next_page_idx[cpu] >= ENTRIES_PER_PAGE); |
4c11d7ae | 1009 | return &array[iter->next_page_idx[cpu]]; |
bc0c38d1 SR |
1010 | } |
1011 | ||
e309b41d | 1012 | static struct trace_entry * |
bc0c38d1 SR |
1013 | find_next_entry(struct trace_iterator *iter, int *ent_cpu) |
1014 | { | |
1015 | struct trace_array *tr = iter->tr; | |
1016 | struct trace_entry *ent, *next = NULL; | |
1017 | int next_cpu = -1; | |
1018 | int cpu; | |
1019 | ||
ab46428c | 1020 | for_each_tracing_cpu(cpu) { |
c7aafc54 | 1021 | if (!head_page(tr->data[cpu])) |
bc0c38d1 | 1022 | continue; |
4c11d7ae | 1023 | ent = trace_entry_idx(tr, tr->data[cpu], iter, cpu); |
cdd31cd2 IM |
1024 | /* |
1025 | * Pick the entry with the smallest timestamp: | |
1026 | */ | |
1027 | if (ent && (!next || ent->t < next->t)) { | |
bc0c38d1 SR |
1028 | next = ent; |
1029 | next_cpu = cpu; | |
1030 | } | |
1031 | } | |
1032 | ||
1033 | if (ent_cpu) | |
1034 | *ent_cpu = next_cpu; | |
1035 | ||
1036 | return next; | |
1037 | } | |
1038 | ||
e309b41d | 1039 | static void trace_iterator_increment(struct trace_iterator *iter) |
bc0c38d1 | 1040 | { |
b3806b43 SR |
1041 | iter->idx++; |
1042 | iter->next_idx[iter->cpu]++; | |
1043 | iter->next_page_idx[iter->cpu]++; | |
8c523a9d | 1044 | |
b3806b43 SR |
1045 | if (iter->next_page_idx[iter->cpu] >= ENTRIES_PER_PAGE) { |
1046 | struct trace_array_cpu *data = iter->tr->data[iter->cpu]; | |
bc0c38d1 | 1047 | |
b3806b43 SR |
1048 | iter->next_page_idx[iter->cpu] = 0; |
1049 | iter->next_page[iter->cpu] = | |
1050 | trace_next_list(data, iter->next_page[iter->cpu]); | |
1051 | } | |
1052 | } | |
bc0c38d1 | 1053 | |
e309b41d | 1054 | static void trace_consume(struct trace_iterator *iter) |
b3806b43 SR |
1055 | { |
1056 | struct trace_array_cpu *data = iter->tr->data[iter->cpu]; | |
1057 | ||
1058 | data->trace_tail_idx++; | |
1059 | if (data->trace_tail_idx >= ENTRIES_PER_PAGE) { | |
1060 | data->trace_tail = trace_next_page(data, data->trace_tail); | |
1061 | data->trace_tail_idx = 0; | |
1062 | } | |
4e3c3333 | 1063 | |
b3806b43 SR |
1064 | /* Check if we empty it, then reset the index */ |
1065 | if (data->trace_head == data->trace_tail && | |
1066 | data->trace_head_idx == data->trace_tail_idx) | |
1067 | data->trace_idx = 0; | |
b3806b43 SR |
1068 | } |
1069 | ||
e309b41d | 1070 | static void *find_next_entry_inc(struct trace_iterator *iter) |
b3806b43 SR |
1071 | { |
1072 | struct trace_entry *next; | |
1073 | int next_cpu = -1; | |
1074 | ||
1075 | next = find_next_entry(iter, &next_cpu); | |
93a588f4 | 1076 | |
4e3c3333 IM |
1077 | iter->prev_ent = iter->ent; |
1078 | iter->prev_cpu = iter->cpu; | |
1079 | ||
bc0c38d1 SR |
1080 | iter->ent = next; |
1081 | iter->cpu = next_cpu; | |
1082 | ||
b3806b43 SR |
1083 | if (next) |
1084 | trace_iterator_increment(iter); | |
1085 | ||
bc0c38d1 SR |
1086 | return next ? iter : NULL; |
1087 | } | |
1088 | ||
e309b41d | 1089 | static void *s_next(struct seq_file *m, void *v, loff_t *pos) |
bc0c38d1 SR |
1090 | { |
1091 | struct trace_iterator *iter = m->private; | |
bc0c38d1 SR |
1092 | void *last_ent = iter->ent; |
1093 | int i = (int)*pos; | |
4e3c3333 | 1094 | void *ent; |
bc0c38d1 SR |
1095 | |
1096 | (*pos)++; | |
1097 | ||
1098 | /* can't go backwards */ | |
1099 | if (iter->idx > i) | |
1100 | return NULL; | |
1101 | ||
1102 | if (iter->idx < 0) | |
1103 | ent = find_next_entry_inc(iter); | |
1104 | else | |
1105 | ent = iter; | |
1106 | ||
1107 | while (ent && iter->idx < i) | |
1108 | ent = find_next_entry_inc(iter); | |
1109 | ||
1110 | iter->pos = *pos; | |
1111 | ||
1112 | if (last_ent && !ent) | |
1113 | seq_puts(m, "\n\nvim:ft=help\n"); | |
1114 | ||
1115 | return ent; | |
1116 | } | |
1117 | ||
1118 | static void *s_start(struct seq_file *m, loff_t *pos) | |
1119 | { | |
1120 | struct trace_iterator *iter = m->private; | |
1121 | void *p = NULL; | |
1122 | loff_t l = 0; | |
1123 | int i; | |
1124 | ||
1125 | mutex_lock(&trace_types_lock); | |
1126 | ||
d15f57f2 SR |
1127 | if (!current_trace || current_trace != iter->trace) { |
1128 | mutex_unlock(&trace_types_lock); | |
bc0c38d1 | 1129 | return NULL; |
d15f57f2 | 1130 | } |
bc0c38d1 SR |
1131 | |
1132 | atomic_inc(&trace_record_cmdline_disabled); | |
1133 | ||
1134 | /* let the tracer grab locks here if needed */ | |
1135 | if (current_trace->start) | |
1136 | current_trace->start(iter); | |
1137 | ||
1138 | if (*pos != iter->pos) { | |
1139 | iter->ent = NULL; | |
1140 | iter->cpu = 0; | |
1141 | iter->idx = -1; | |
4e3c3333 IM |
1142 | iter->prev_ent = NULL; |
1143 | iter->prev_cpu = -1; | |
bc0c38d1 | 1144 | |
ab46428c | 1145 | for_each_tracing_cpu(i) { |
bc0c38d1 | 1146 | iter->next_idx[i] = 0; |
4c11d7ae SR |
1147 | iter->next_page[i] = NULL; |
1148 | } | |
bc0c38d1 SR |
1149 | |
1150 | for (p = iter; p && l < *pos; p = s_next(m, p, &l)) | |
1151 | ; | |
1152 | ||
1153 | } else { | |
4c11d7ae | 1154 | l = *pos - 1; |
bc0c38d1 SR |
1155 | p = s_next(m, p, &l); |
1156 | } | |
1157 | ||
1158 | return p; | |
1159 | } | |
1160 | ||
1161 | static void s_stop(struct seq_file *m, void *p) | |
1162 | { | |
1163 | struct trace_iterator *iter = m->private; | |
1164 | ||
1165 | atomic_dec(&trace_record_cmdline_disabled); | |
1166 | ||
1167 | /* let the tracer release locks here if needed */ | |
1168 | if (current_trace && current_trace == iter->trace && iter->trace->stop) | |
1169 | iter->trace->stop(iter); | |
1170 | ||
1171 | mutex_unlock(&trace_types_lock); | |
1172 | } | |
1173 | ||
b3806b43 | 1174 | static int |
214023c3 | 1175 | seq_print_sym_short(struct trace_seq *s, const char *fmt, unsigned long address) |
bc0c38d1 SR |
1176 | { |
1177 | #ifdef CONFIG_KALLSYMS | |
1178 | char str[KSYM_SYMBOL_LEN]; | |
1179 | ||
1180 | kallsyms_lookup(address, NULL, NULL, NULL, str); | |
1181 | ||
b3806b43 | 1182 | return trace_seq_printf(s, fmt, str); |
bc0c38d1 | 1183 | #endif |
b3806b43 | 1184 | return 1; |
bc0c38d1 SR |
1185 | } |
1186 | ||
b3806b43 | 1187 | static int |
214023c3 SR |
1188 | seq_print_sym_offset(struct trace_seq *s, const char *fmt, |
1189 | unsigned long address) | |
bc0c38d1 SR |
1190 | { |
1191 | #ifdef CONFIG_KALLSYMS | |
1192 | char str[KSYM_SYMBOL_LEN]; | |
1193 | ||
1194 | sprint_symbol(str, address); | |
b3806b43 | 1195 | return trace_seq_printf(s, fmt, str); |
bc0c38d1 | 1196 | #endif |
b3806b43 | 1197 | return 1; |
bc0c38d1 SR |
1198 | } |
1199 | ||
1200 | #ifndef CONFIG_64BIT | |
1201 | # define IP_FMT "%08lx" | |
1202 | #else | |
1203 | # define IP_FMT "%016lx" | |
1204 | #endif | |
1205 | ||
e309b41d | 1206 | static int |
214023c3 | 1207 | seq_print_ip_sym(struct trace_seq *s, unsigned long ip, unsigned long sym_flags) |
bc0c38d1 | 1208 | { |
b3806b43 SR |
1209 | int ret; |
1210 | ||
1211 | if (!ip) | |
1212 | return trace_seq_printf(s, "0"); | |
bc0c38d1 SR |
1213 | |
1214 | if (sym_flags & TRACE_ITER_SYM_OFFSET) | |
b3806b43 | 1215 | ret = seq_print_sym_offset(s, "%s", ip); |
bc0c38d1 | 1216 | else |
b3806b43 SR |
1217 | ret = seq_print_sym_short(s, "%s", ip); |
1218 | ||
1219 | if (!ret) | |
1220 | return 0; | |
bc0c38d1 SR |
1221 | |
1222 | if (sym_flags & TRACE_ITER_SYM_ADDR) | |
b3806b43 SR |
1223 | ret = trace_seq_printf(s, " <" IP_FMT ">", ip); |
1224 | return ret; | |
bc0c38d1 SR |
1225 | } |
1226 | ||
e309b41d | 1227 | static void print_lat_help_header(struct seq_file *m) |
bc0c38d1 SR |
1228 | { |
1229 | seq_puts(m, "# _------=> CPU# \n"); | |
1230 | seq_puts(m, "# / _-----=> irqs-off \n"); | |
1231 | seq_puts(m, "# | / _----=> need-resched \n"); | |
1232 | seq_puts(m, "# || / _---=> hardirq/softirq \n"); | |
1233 | seq_puts(m, "# ||| / _--=> preempt-depth \n"); | |
1234 | seq_puts(m, "# |||| / \n"); | |
1235 | seq_puts(m, "# ||||| delay \n"); | |
1236 | seq_puts(m, "# cmd pid ||||| time | caller \n"); | |
1237 | seq_puts(m, "# \\ / ||||| \\ | / \n"); | |
1238 | } | |
1239 | ||
e309b41d | 1240 | static void print_func_help_header(struct seq_file *m) |
bc0c38d1 SR |
1241 | { |
1242 | seq_puts(m, "# TASK-PID CPU# TIMESTAMP FUNCTION\n"); | |
1243 | seq_puts(m, "# | | | | |\n"); | |
1244 | } | |
1245 | ||
1246 | ||
e309b41d | 1247 | static void |
bc0c38d1 SR |
1248 | print_trace_header(struct seq_file *m, struct trace_iterator *iter) |
1249 | { | |
1250 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); | |
1251 | struct trace_array *tr = iter->tr; | |
1252 | struct trace_array_cpu *data = tr->data[tr->cpu]; | |
1253 | struct tracer *type = current_trace; | |
4c11d7ae SR |
1254 | unsigned long total = 0; |
1255 | unsigned long entries = 0; | |
bc0c38d1 SR |
1256 | int cpu; |
1257 | const char *name = "preemption"; | |
1258 | ||
1259 | if (type) | |
1260 | name = type->name; | |
1261 | ||
ab46428c | 1262 | for_each_tracing_cpu(cpu) { |
c7aafc54 | 1263 | if (head_page(tr->data[cpu])) { |
4c11d7ae SR |
1264 | total += tr->data[cpu]->trace_idx; |
1265 | if (tr->data[cpu]->trace_idx > tr->entries) | |
bc0c38d1 | 1266 | entries += tr->entries; |
4c11d7ae | 1267 | else |
bc0c38d1 SR |
1268 | entries += tr->data[cpu]->trace_idx; |
1269 | } | |
1270 | } | |
1271 | ||
1272 | seq_printf(m, "%s latency trace v1.1.5 on %s\n", | |
1273 | name, UTS_RELEASE); | |
1274 | seq_puts(m, "-----------------------------------" | |
1275 | "---------------------------------\n"); | |
1276 | seq_printf(m, " latency: %lu us, #%lu/%lu, CPU#%d |" | |
1277 | " (M:%s VP:%d, KP:%d, SP:%d HP:%d", | |
57f50be1 | 1278 | nsecs_to_usecs(data->saved_latency), |
bc0c38d1 | 1279 | entries, |
4c11d7ae | 1280 | total, |
bc0c38d1 SR |
1281 | tr->cpu, |
1282 | #if defined(CONFIG_PREEMPT_NONE) | |
1283 | "server", | |
1284 | #elif defined(CONFIG_PREEMPT_VOLUNTARY) | |
1285 | "desktop", | |
1286 | #elif defined(CONFIG_PREEMPT_DESKTOP) | |
1287 | "preempt", | |
1288 | #else | |
1289 | "unknown", | |
1290 | #endif | |
1291 | /* These are reserved for later use */ | |
1292 | 0, 0, 0, 0); | |
1293 | #ifdef CONFIG_SMP | |
1294 | seq_printf(m, " #P:%d)\n", num_online_cpus()); | |
1295 | #else | |
1296 | seq_puts(m, ")\n"); | |
1297 | #endif | |
1298 | seq_puts(m, " -----------------\n"); | |
1299 | seq_printf(m, " | task: %.16s-%d " | |
1300 | "(uid:%d nice:%ld policy:%ld rt_prio:%ld)\n", | |
1301 | data->comm, data->pid, data->uid, data->nice, | |
1302 | data->policy, data->rt_priority); | |
1303 | seq_puts(m, " -----------------\n"); | |
1304 | ||
1305 | if (data->critical_start) { | |
1306 | seq_puts(m, " => started at: "); | |
214023c3 SR |
1307 | seq_print_ip_sym(&iter->seq, data->critical_start, sym_flags); |
1308 | trace_print_seq(m, &iter->seq); | |
bc0c38d1 | 1309 | seq_puts(m, "\n => ended at: "); |
214023c3 SR |
1310 | seq_print_ip_sym(&iter->seq, data->critical_end, sym_flags); |
1311 | trace_print_seq(m, &iter->seq); | |
bc0c38d1 SR |
1312 | seq_puts(m, "\n"); |
1313 | } | |
1314 | ||
1315 | seq_puts(m, "\n"); | |
1316 | } | |
1317 | ||
e309b41d | 1318 | static void |
214023c3 | 1319 | lat_print_generic(struct trace_seq *s, struct trace_entry *entry, int cpu) |
bc0c38d1 SR |
1320 | { |
1321 | int hardirq, softirq; | |
1322 | char *comm; | |
1323 | ||
1324 | comm = trace_find_cmdline(entry->pid); | |
1325 | ||
214023c3 SR |
1326 | trace_seq_printf(s, "%8.8s-%-5d ", comm, entry->pid); |
1327 | trace_seq_printf(s, "%d", cpu); | |
1328 | trace_seq_printf(s, "%c%c", | |
1329 | (entry->flags & TRACE_FLAG_IRQS_OFF) ? 'd' : '.', | |
1330 | ((entry->flags & TRACE_FLAG_NEED_RESCHED) ? 'N' : '.')); | |
bc0c38d1 SR |
1331 | |
1332 | hardirq = entry->flags & TRACE_FLAG_HARDIRQ; | |
1333 | softirq = entry->flags & TRACE_FLAG_SOFTIRQ; | |
afc2abc0 | 1334 | if (hardirq && softirq) { |
214023c3 | 1335 | trace_seq_putc(s, 'H'); |
afc2abc0 IM |
1336 | } else { |
1337 | if (hardirq) { | |
214023c3 | 1338 | trace_seq_putc(s, 'h'); |
afc2abc0 | 1339 | } else { |
bc0c38d1 | 1340 | if (softirq) |
214023c3 | 1341 | trace_seq_putc(s, 's'); |
bc0c38d1 | 1342 | else |
214023c3 | 1343 | trace_seq_putc(s, '.'); |
bc0c38d1 SR |
1344 | } |
1345 | } | |
1346 | ||
1347 | if (entry->preempt_count) | |
214023c3 | 1348 | trace_seq_printf(s, "%x", entry->preempt_count); |
bc0c38d1 | 1349 | else |
214023c3 | 1350 | trace_seq_puts(s, "."); |
bc0c38d1 SR |
1351 | } |
1352 | ||
1353 | unsigned long preempt_mark_thresh = 100; | |
1354 | ||
e309b41d | 1355 | static void |
214023c3 | 1356 | lat_print_timestamp(struct trace_seq *s, unsigned long long abs_usecs, |
bc0c38d1 SR |
1357 | unsigned long rel_usecs) |
1358 | { | |
214023c3 | 1359 | trace_seq_printf(s, " %4lldus", abs_usecs); |
bc0c38d1 | 1360 | if (rel_usecs > preempt_mark_thresh) |
214023c3 | 1361 | trace_seq_puts(s, "!: "); |
bc0c38d1 | 1362 | else if (rel_usecs > 1) |
214023c3 | 1363 | trace_seq_puts(s, "+: "); |
bc0c38d1 | 1364 | else |
214023c3 | 1365 | trace_seq_puts(s, " : "); |
bc0c38d1 SR |
1366 | } |
1367 | ||
1368 | static const char state_to_char[] = TASK_STATE_TO_CHAR_STR; | |
1369 | ||
e309b41d | 1370 | static int |
214023c3 | 1371 | print_lat_fmt(struct trace_iterator *iter, unsigned int trace_idx, int cpu) |
bc0c38d1 | 1372 | { |
214023c3 | 1373 | struct trace_seq *s = &iter->seq; |
bc0c38d1 SR |
1374 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); |
1375 | struct trace_entry *next_entry = find_next_entry(iter, NULL); | |
1376 | unsigned long verbose = (trace_flags & TRACE_ITER_VERBOSE); | |
1377 | struct trace_entry *entry = iter->ent; | |
1378 | unsigned long abs_usecs; | |
1379 | unsigned long rel_usecs; | |
1380 | char *comm; | |
bac524d3 | 1381 | int S, T; |
86387f7e | 1382 | int i; |
d17d9691 | 1383 | unsigned state; |
bc0c38d1 SR |
1384 | |
1385 | if (!next_entry) | |
1386 | next_entry = entry; | |
1387 | rel_usecs = ns2usecs(next_entry->t - entry->t); | |
1388 | abs_usecs = ns2usecs(entry->t - iter->tr->time_start); | |
1389 | ||
1390 | if (verbose) { | |
1391 | comm = trace_find_cmdline(entry->pid); | |
214023c3 SR |
1392 | trace_seq_printf(s, "%16s %5d %d %d %08x %08x [%08lx]" |
1393 | " %ld.%03ldms (+%ld.%03ldms): ", | |
1394 | comm, | |
1395 | entry->pid, cpu, entry->flags, | |
1396 | entry->preempt_count, trace_idx, | |
1397 | ns2usecs(entry->t), | |
1398 | abs_usecs/1000, | |
1399 | abs_usecs % 1000, rel_usecs/1000, | |
1400 | rel_usecs % 1000); | |
bc0c38d1 | 1401 | } else { |
f29c73fe IM |
1402 | lat_print_generic(s, entry, cpu); |
1403 | lat_print_timestamp(s, abs_usecs, rel_usecs); | |
bc0c38d1 SR |
1404 | } |
1405 | switch (entry->type) { | |
1406 | case TRACE_FN: | |
214023c3 SR |
1407 | seq_print_ip_sym(s, entry->fn.ip, sym_flags); |
1408 | trace_seq_puts(s, " ("); | |
1409 | seq_print_ip_sym(s, entry->fn.parent_ip, sym_flags); | |
1410 | trace_seq_puts(s, ")\n"); | |
bc0c38d1 SR |
1411 | break; |
1412 | case TRACE_CTX: | |
57422797 | 1413 | case TRACE_WAKE: |
bac524d3 PZ |
1414 | T = entry->ctx.next_state < sizeof(state_to_char) ? |
1415 | state_to_char[entry->ctx.next_state] : 'X'; | |
1416 | ||
d17d9691 AG |
1417 | state = entry->ctx.prev_state ? __ffs(entry->ctx.prev_state) + 1 : 0; |
1418 | S = state < sizeof(state_to_char) - 1 ? state_to_char[state] : 'X'; | |
bc0c38d1 | 1419 | comm = trace_find_cmdline(entry->ctx.next_pid); |
bac524d3 | 1420 | trace_seq_printf(s, " %5d:%3d:%c %s %5d:%3d:%c %s\n", |
214023c3 SR |
1421 | entry->ctx.prev_pid, |
1422 | entry->ctx.prev_prio, | |
57422797 | 1423 | S, entry->type == TRACE_CTX ? "==>" : " +", |
214023c3 SR |
1424 | entry->ctx.next_pid, |
1425 | entry->ctx.next_prio, | |
bac524d3 | 1426 | T, comm); |
bc0c38d1 | 1427 | break; |
f0a920d5 | 1428 | case TRACE_SPECIAL: |
88a4216c | 1429 | trace_seq_printf(s, "# %ld %ld %ld\n", |
f0a920d5 IM |
1430 | entry->special.arg1, |
1431 | entry->special.arg2, | |
1432 | entry->special.arg3); | |
1433 | break; | |
86387f7e IM |
1434 | case TRACE_STACK: |
1435 | for (i = 0; i < FTRACE_STACK_ENTRIES; i++) { | |
1436 | if (i) | |
1437 | trace_seq_puts(s, " <= "); | |
1438 | seq_print_ip_sym(s, entry->stack.caller[i], sym_flags); | |
1439 | } | |
1440 | trace_seq_puts(s, "\n"); | |
1441 | break; | |
89b2f978 | 1442 | default: |
214023c3 | 1443 | trace_seq_printf(s, "Unknown type %d\n", entry->type); |
bc0c38d1 | 1444 | } |
f9896bf3 | 1445 | return 1; |
bc0c38d1 SR |
1446 | } |
1447 | ||
e309b41d | 1448 | static int print_trace_fmt(struct trace_iterator *iter) |
bc0c38d1 | 1449 | { |
214023c3 | 1450 | struct trace_seq *s = &iter->seq; |
bc0c38d1 | 1451 | unsigned long sym_flags = (trace_flags & TRACE_ITER_SYM_MASK); |
4e3c3333 | 1452 | struct trace_entry *entry; |
bc0c38d1 SR |
1453 | unsigned long usec_rem; |
1454 | unsigned long long t; | |
1455 | unsigned long secs; | |
1456 | char *comm; | |
b3806b43 | 1457 | int ret; |
bac524d3 | 1458 | int S, T; |
86387f7e | 1459 | int i; |
bc0c38d1 | 1460 | |
4e3c3333 IM |
1461 | entry = iter->ent; |
1462 | ||
bc0c38d1 SR |
1463 | comm = trace_find_cmdline(iter->ent->pid); |
1464 | ||
cdd31cd2 | 1465 | t = ns2usecs(entry->t); |
bc0c38d1 SR |
1466 | usec_rem = do_div(t, 1000000ULL); |
1467 | secs = (unsigned long)t; | |
1468 | ||
f29c73fe IM |
1469 | ret = trace_seq_printf(s, "%16s-%-5d ", comm, entry->pid); |
1470 | if (!ret) | |
1471 | return 0; | |
1472 | ret = trace_seq_printf(s, "[%02d] ", iter->cpu); | |
1473 | if (!ret) | |
1474 | return 0; | |
1475 | ret = trace_seq_printf(s, "%5lu.%06lu: ", secs, usec_rem); | |
1476 | if (!ret) | |
1477 | return 0; | |
bc0c38d1 SR |
1478 | |
1479 | switch (entry->type) { | |
1480 | case TRACE_FN: | |
b3806b43 SR |
1481 | ret = seq_print_ip_sym(s, entry->fn.ip, sym_flags); |
1482 | if (!ret) | |
1483 | return 0; | |
bc0c38d1 SR |
1484 | if ((sym_flags & TRACE_ITER_PRINT_PARENT) && |
1485 | entry->fn.parent_ip) { | |
b3806b43 SR |
1486 | ret = trace_seq_printf(s, " <-"); |
1487 | if (!ret) | |
1488 | return 0; | |
1489 | ret = seq_print_ip_sym(s, entry->fn.parent_ip, | |
1490 | sym_flags); | |
1491 | if (!ret) | |
1492 | return 0; | |
bc0c38d1 | 1493 | } |
b3806b43 SR |
1494 | ret = trace_seq_printf(s, "\n"); |
1495 | if (!ret) | |
1496 | return 0; | |
bc0c38d1 SR |
1497 | break; |
1498 | case TRACE_CTX: | |
57422797 | 1499 | case TRACE_WAKE: |
bc0c38d1 SR |
1500 | S = entry->ctx.prev_state < sizeof(state_to_char) ? |
1501 | state_to_char[entry->ctx.prev_state] : 'X'; | |
bac524d3 PZ |
1502 | T = entry->ctx.next_state < sizeof(state_to_char) ? |
1503 | state_to_char[entry->ctx.next_state] : 'X'; | |
1504 | ret = trace_seq_printf(s, " %5d:%3d:%c %s %5d:%3d:%c\n", | |
b3806b43 SR |
1505 | entry->ctx.prev_pid, |
1506 | entry->ctx.prev_prio, | |
1507 | S, | |
57422797 | 1508 | entry->type == TRACE_CTX ? "==>" : " +", |
b3806b43 | 1509 | entry->ctx.next_pid, |
bac524d3 PZ |
1510 | entry->ctx.next_prio, |
1511 | T); | |
b3806b43 SR |
1512 | if (!ret) |
1513 | return 0; | |
bc0c38d1 | 1514 | break; |
f0a920d5 | 1515 | case TRACE_SPECIAL: |
88a4216c | 1516 | ret = trace_seq_printf(s, "# %ld %ld %ld\n", |
f0a920d5 IM |
1517 | entry->special.arg1, |
1518 | entry->special.arg2, | |
1519 | entry->special.arg3); | |
1520 | if (!ret) | |
1521 | return 0; | |
1522 | break; | |
86387f7e IM |
1523 | case TRACE_STACK: |
1524 | for (i = 0; i < FTRACE_STACK_ENTRIES; i++) { | |
1525 | if (i) { | |
1526 | ret = trace_seq_puts(s, " <= "); | |
1527 | if (!ret) | |
1528 | return 0; | |
1529 | } | |
1530 | ret = seq_print_ip_sym(s, entry->stack.caller[i], | |
1531 | sym_flags); | |
1532 | if (!ret) | |
1533 | return 0; | |
1534 | } | |
1535 | ret = trace_seq_puts(s, "\n"); | |
1536 | if (!ret) | |
1537 | return 0; | |
1538 | break; | |
bc0c38d1 | 1539 | } |
b3806b43 | 1540 | return 1; |
bc0c38d1 SR |
1541 | } |
1542 | ||
e309b41d | 1543 | static int print_raw_fmt(struct trace_iterator *iter) |
f9896bf3 IM |
1544 | { |
1545 | struct trace_seq *s = &iter->seq; | |
1546 | struct trace_entry *entry; | |
1547 | int ret; | |
bac524d3 | 1548 | int S, T; |
f9896bf3 IM |
1549 | |
1550 | entry = iter->ent; | |
1551 | ||
1552 | ret = trace_seq_printf(s, "%d %d %llu ", | |
1553 | entry->pid, iter->cpu, entry->t); | |
1554 | if (!ret) | |
1555 | return 0; | |
1556 | ||
1557 | switch (entry->type) { | |
1558 | case TRACE_FN: | |
1559 | ret = trace_seq_printf(s, "%x %x\n", | |
1560 | entry->fn.ip, entry->fn.parent_ip); | |
1561 | if (!ret) | |
1562 | return 0; | |
1563 | break; | |
1564 | case TRACE_CTX: | |
57422797 | 1565 | case TRACE_WAKE: |
f9896bf3 IM |
1566 | S = entry->ctx.prev_state < sizeof(state_to_char) ? |
1567 | state_to_char[entry->ctx.prev_state] : 'X'; | |
bac524d3 PZ |
1568 | T = entry->ctx.next_state < sizeof(state_to_char) ? |
1569 | state_to_char[entry->ctx.next_state] : 'X'; | |
57422797 IM |
1570 | if (entry->type == TRACE_WAKE) |
1571 | S = '+'; | |
bac524d3 | 1572 | ret = trace_seq_printf(s, "%d %d %c %d %d %c\n", |
f9896bf3 IM |
1573 | entry->ctx.prev_pid, |
1574 | entry->ctx.prev_prio, | |
1575 | S, | |
1576 | entry->ctx.next_pid, | |
bac524d3 PZ |
1577 | entry->ctx.next_prio, |
1578 | T); | |
f9896bf3 IM |
1579 | if (!ret) |
1580 | return 0; | |
1581 | break; | |
f0a920d5 | 1582 | case TRACE_SPECIAL: |
86387f7e | 1583 | case TRACE_STACK: |
88a4216c | 1584 | ret = trace_seq_printf(s, "# %ld %ld %ld\n", |
f0a920d5 IM |
1585 | entry->special.arg1, |
1586 | entry->special.arg2, | |
1587 | entry->special.arg3); | |
1588 | if (!ret) | |
1589 | return 0; | |
1590 | break; | |
f9896bf3 IM |
1591 | } |
1592 | return 1; | |
1593 | } | |
1594 | ||
cb0f12aa IM |
1595 | #define SEQ_PUT_FIELD_RET(s, x) \ |
1596 | do { \ | |
1597 | if (!trace_seq_putmem(s, &(x), sizeof(x))) \ | |
1598 | return 0; \ | |
1599 | } while (0) | |
1600 | ||
5e3ca0ec IM |
1601 | #define SEQ_PUT_HEX_FIELD_RET(s, x) \ |
1602 | do { \ | |
1603 | if (!trace_seq_putmem_hex(s, &(x), sizeof(x))) \ | |
1604 | return 0; \ | |
1605 | } while (0) | |
1606 | ||
e309b41d | 1607 | static int print_hex_fmt(struct trace_iterator *iter) |
5e3ca0ec IM |
1608 | { |
1609 | struct trace_seq *s = &iter->seq; | |
1610 | unsigned char newline = '\n'; | |
1611 | struct trace_entry *entry; | |
bac524d3 | 1612 | int S, T; |
5e3ca0ec IM |
1613 | |
1614 | entry = iter->ent; | |
1615 | ||
1616 | SEQ_PUT_HEX_FIELD_RET(s, entry->pid); | |
1617 | SEQ_PUT_HEX_FIELD_RET(s, iter->cpu); | |
1618 | SEQ_PUT_HEX_FIELD_RET(s, entry->t); | |
1619 | ||
1620 | switch (entry->type) { | |
1621 | case TRACE_FN: | |
1622 | SEQ_PUT_HEX_FIELD_RET(s, entry->fn.ip); | |
1623 | SEQ_PUT_HEX_FIELD_RET(s, entry->fn.parent_ip); | |
1624 | break; | |
1625 | case TRACE_CTX: | |
57422797 | 1626 | case TRACE_WAKE: |
5e3ca0ec IM |
1627 | S = entry->ctx.prev_state < sizeof(state_to_char) ? |
1628 | state_to_char[entry->ctx.prev_state] : 'X'; | |
bac524d3 PZ |
1629 | T = entry->ctx.next_state < sizeof(state_to_char) ? |
1630 | state_to_char[entry->ctx.next_state] : 'X'; | |
57422797 IM |
1631 | if (entry->type == TRACE_WAKE) |
1632 | S = '+'; | |
5e3ca0ec IM |
1633 | SEQ_PUT_HEX_FIELD_RET(s, entry->ctx.prev_pid); |
1634 | SEQ_PUT_HEX_FIELD_RET(s, entry->ctx.prev_prio); | |
1635 | SEQ_PUT_HEX_FIELD_RET(s, S); | |
1636 | SEQ_PUT_HEX_FIELD_RET(s, entry->ctx.next_pid); | |
1637 | SEQ_PUT_HEX_FIELD_RET(s, entry->ctx.next_prio); | |
1638 | SEQ_PUT_HEX_FIELD_RET(s, entry->fn.parent_ip); | |
bac524d3 | 1639 | SEQ_PUT_HEX_FIELD_RET(s, T); |
5e3ca0ec IM |
1640 | break; |
1641 | case TRACE_SPECIAL: | |
86387f7e | 1642 | case TRACE_STACK: |
5e3ca0ec IM |
1643 | SEQ_PUT_HEX_FIELD_RET(s, entry->special.arg1); |
1644 | SEQ_PUT_HEX_FIELD_RET(s, entry->special.arg2); | |
1645 | SEQ_PUT_HEX_FIELD_RET(s, entry->special.arg3); | |
1646 | break; | |
1647 | } | |
1648 | SEQ_PUT_FIELD_RET(s, newline); | |
1649 | ||
1650 | return 1; | |
1651 | } | |
1652 | ||
e309b41d | 1653 | static int print_bin_fmt(struct trace_iterator *iter) |
cb0f12aa IM |
1654 | { |
1655 | struct trace_seq *s = &iter->seq; | |
1656 | struct trace_entry *entry; | |
1657 | ||
1658 | entry = iter->ent; | |
1659 | ||
1660 | SEQ_PUT_FIELD_RET(s, entry->pid); | |
1661 | SEQ_PUT_FIELD_RET(s, entry->cpu); | |
1662 | SEQ_PUT_FIELD_RET(s, entry->t); | |
1663 | ||
1664 | switch (entry->type) { | |
1665 | case TRACE_FN: | |
1666 | SEQ_PUT_FIELD_RET(s, entry->fn.ip); | |
1667 | SEQ_PUT_FIELD_RET(s, entry->fn.parent_ip); | |
1668 | break; | |
1669 | case TRACE_CTX: | |
1670 | SEQ_PUT_FIELD_RET(s, entry->ctx.prev_pid); | |
1671 | SEQ_PUT_FIELD_RET(s, entry->ctx.prev_prio); | |
1672 | SEQ_PUT_FIELD_RET(s, entry->ctx.prev_state); | |
1673 | SEQ_PUT_FIELD_RET(s, entry->ctx.next_pid); | |
1674 | SEQ_PUT_FIELD_RET(s, entry->ctx.next_prio); | |
bac524d3 | 1675 | SEQ_PUT_FIELD_RET(s, entry->ctx.next_state); |
cb0f12aa | 1676 | break; |
f0a920d5 | 1677 | case TRACE_SPECIAL: |
86387f7e | 1678 | case TRACE_STACK: |
f0a920d5 IM |
1679 | SEQ_PUT_FIELD_RET(s, entry->special.arg1); |
1680 | SEQ_PUT_FIELD_RET(s, entry->special.arg2); | |
1681 | SEQ_PUT_FIELD_RET(s, entry->special.arg3); | |
1682 | break; | |
cb0f12aa IM |
1683 | } |
1684 | return 1; | |
1685 | } | |
1686 | ||
bc0c38d1 SR |
1687 | static int trace_empty(struct trace_iterator *iter) |
1688 | { | |
1689 | struct trace_array_cpu *data; | |
1690 | int cpu; | |
1691 | ||
ab46428c | 1692 | for_each_tracing_cpu(cpu) { |
bc0c38d1 SR |
1693 | data = iter->tr->data[cpu]; |
1694 | ||
b3806b43 SR |
1695 | if (head_page(data) && data->trace_idx && |
1696 | (data->trace_tail != data->trace_head || | |
1697 | data->trace_tail_idx != data->trace_head_idx)) | |
bc0c38d1 SR |
1698 | return 0; |
1699 | } | |
1700 | return 1; | |
1701 | } | |
1702 | ||
f9896bf3 IM |
1703 | static int print_trace_line(struct trace_iterator *iter) |
1704 | { | |
72829bc3 TG |
1705 | if (iter->trace && iter->trace->print_line) |
1706 | return iter->trace->print_line(iter); | |
1707 | ||
cb0f12aa IM |
1708 | if (trace_flags & TRACE_ITER_BIN) |
1709 | return print_bin_fmt(iter); | |
1710 | ||
5e3ca0ec IM |
1711 | if (trace_flags & TRACE_ITER_HEX) |
1712 | return print_hex_fmt(iter); | |
1713 | ||
f9896bf3 IM |
1714 | if (trace_flags & TRACE_ITER_RAW) |
1715 | return print_raw_fmt(iter); | |
1716 | ||
1717 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) | |
1718 | return print_lat_fmt(iter, iter->idx, iter->cpu); | |
1719 | ||
1720 | return print_trace_fmt(iter); | |
1721 | } | |
1722 | ||
bc0c38d1 SR |
1723 | static int s_show(struct seq_file *m, void *v) |
1724 | { | |
1725 | struct trace_iterator *iter = v; | |
1726 | ||
1727 | if (iter->ent == NULL) { | |
1728 | if (iter->tr) { | |
1729 | seq_printf(m, "# tracer: %s\n", iter->trace->name); | |
1730 | seq_puts(m, "#\n"); | |
1731 | } | |
1732 | if (iter->iter_flags & TRACE_FILE_LAT_FMT) { | |
1733 | /* print nothing if the buffers are empty */ | |
1734 | if (trace_empty(iter)) | |
1735 | return 0; | |
1736 | print_trace_header(m, iter); | |
1737 | if (!(trace_flags & TRACE_ITER_VERBOSE)) | |
1738 | print_lat_help_header(m); | |
1739 | } else { | |
1740 | if (!(trace_flags & TRACE_ITER_VERBOSE)) | |
1741 | print_func_help_header(m); | |
1742 | } | |
1743 | } else { | |
f9896bf3 | 1744 | print_trace_line(iter); |
214023c3 | 1745 | trace_print_seq(m, &iter->seq); |
bc0c38d1 SR |
1746 | } |
1747 | ||
1748 | return 0; | |
1749 | } | |
1750 | ||
1751 | static struct seq_operations tracer_seq_ops = { | |
4bf39a94 IM |
1752 | .start = s_start, |
1753 | .next = s_next, | |
1754 | .stop = s_stop, | |
1755 | .show = s_show, | |
bc0c38d1 SR |
1756 | }; |
1757 | ||
e309b41d | 1758 | static struct trace_iterator * |
bc0c38d1 SR |
1759 | __tracing_open(struct inode *inode, struct file *file, int *ret) |
1760 | { | |
1761 | struct trace_iterator *iter; | |
1762 | ||
60a11774 SR |
1763 | if (tracing_disabled) { |
1764 | *ret = -ENODEV; | |
1765 | return NULL; | |
1766 | } | |
1767 | ||
bc0c38d1 SR |
1768 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); |
1769 | if (!iter) { | |
1770 | *ret = -ENOMEM; | |
1771 | goto out; | |
1772 | } | |
1773 | ||
1774 | mutex_lock(&trace_types_lock); | |
1775 | if (current_trace && current_trace->print_max) | |
1776 | iter->tr = &max_tr; | |
1777 | else | |
1778 | iter->tr = inode->i_private; | |
1779 | iter->trace = current_trace; | |
1780 | iter->pos = -1; | |
1781 | ||
1782 | /* TODO stop tracer */ | |
1783 | *ret = seq_open(file, &tracer_seq_ops); | |
1784 | if (!*ret) { | |
1785 | struct seq_file *m = file->private_data; | |
1786 | m->private = iter; | |
1787 | ||
1788 | /* stop the trace while dumping */ | |
1789 | if (iter->tr->ctrl) | |
1790 | tracer_enabled = 0; | |
1791 | ||
1792 | if (iter->trace && iter->trace->open) | |
1793 | iter->trace->open(iter); | |
1794 | } else { | |
1795 | kfree(iter); | |
1796 | iter = NULL; | |
1797 | } | |
1798 | mutex_unlock(&trace_types_lock); | |
1799 | ||
1800 | out: | |
1801 | return iter; | |
1802 | } | |
1803 | ||
1804 | int tracing_open_generic(struct inode *inode, struct file *filp) | |
1805 | { | |
60a11774 SR |
1806 | if (tracing_disabled) |
1807 | return -ENODEV; | |
1808 | ||
bc0c38d1 SR |
1809 | filp->private_data = inode->i_private; |
1810 | return 0; | |
1811 | } | |
1812 | ||
1813 | int tracing_release(struct inode *inode, struct file *file) | |
1814 | { | |
1815 | struct seq_file *m = (struct seq_file *)file->private_data; | |
1816 | struct trace_iterator *iter = m->private; | |
1817 | ||
1818 | mutex_lock(&trace_types_lock); | |
1819 | if (iter->trace && iter->trace->close) | |
1820 | iter->trace->close(iter); | |
1821 | ||
1822 | /* reenable tracing if it was previously enabled */ | |
1823 | if (iter->tr->ctrl) | |
1824 | tracer_enabled = 1; | |
1825 | mutex_unlock(&trace_types_lock); | |
1826 | ||
1827 | seq_release(inode, file); | |
1828 | kfree(iter); | |
1829 | return 0; | |
1830 | } | |
1831 | ||
1832 | static int tracing_open(struct inode *inode, struct file *file) | |
1833 | { | |
1834 | int ret; | |
1835 | ||
1836 | __tracing_open(inode, file, &ret); | |
1837 | ||
1838 | return ret; | |
1839 | } | |
1840 | ||
1841 | static int tracing_lt_open(struct inode *inode, struct file *file) | |
1842 | { | |
1843 | struct trace_iterator *iter; | |
1844 | int ret; | |
1845 | ||
1846 | iter = __tracing_open(inode, file, &ret); | |
1847 | ||
1848 | if (!ret) | |
1849 | iter->iter_flags |= TRACE_FILE_LAT_FMT; | |
1850 | ||
1851 | return ret; | |
1852 | } | |
1853 | ||
1854 | ||
e309b41d | 1855 | static void * |
bc0c38d1 SR |
1856 | t_next(struct seq_file *m, void *v, loff_t *pos) |
1857 | { | |
1858 | struct tracer *t = m->private; | |
1859 | ||
1860 | (*pos)++; | |
1861 | ||
1862 | if (t) | |
1863 | t = t->next; | |
1864 | ||
1865 | m->private = t; | |
1866 | ||
1867 | return t; | |
1868 | } | |
1869 | ||
1870 | static void *t_start(struct seq_file *m, loff_t *pos) | |
1871 | { | |
1872 | struct tracer *t = m->private; | |
1873 | loff_t l = 0; | |
1874 | ||
1875 | mutex_lock(&trace_types_lock); | |
1876 | for (; t && l < *pos; t = t_next(m, t, &l)) | |
1877 | ; | |
1878 | ||
1879 | return t; | |
1880 | } | |
1881 | ||
1882 | static void t_stop(struct seq_file *m, void *p) | |
1883 | { | |
1884 | mutex_unlock(&trace_types_lock); | |
1885 | } | |
1886 | ||
1887 | static int t_show(struct seq_file *m, void *v) | |
1888 | { | |
1889 | struct tracer *t = v; | |
1890 | ||
1891 | if (!t) | |
1892 | return 0; | |
1893 | ||
1894 | seq_printf(m, "%s", t->name); | |
1895 | if (t->next) | |
1896 | seq_putc(m, ' '); | |
1897 | else | |
1898 | seq_putc(m, '\n'); | |
1899 | ||
1900 | return 0; | |
1901 | } | |
1902 | ||
1903 | static struct seq_operations show_traces_seq_ops = { | |
4bf39a94 IM |
1904 | .start = t_start, |
1905 | .next = t_next, | |
1906 | .stop = t_stop, | |
1907 | .show = t_show, | |
bc0c38d1 SR |
1908 | }; |
1909 | ||
1910 | static int show_traces_open(struct inode *inode, struct file *file) | |
1911 | { | |
1912 | int ret; | |
1913 | ||
60a11774 SR |
1914 | if (tracing_disabled) |
1915 | return -ENODEV; | |
1916 | ||
bc0c38d1 SR |
1917 | ret = seq_open(file, &show_traces_seq_ops); |
1918 | if (!ret) { | |
1919 | struct seq_file *m = file->private_data; | |
1920 | m->private = trace_types; | |
1921 | } | |
1922 | ||
1923 | return ret; | |
1924 | } | |
1925 | ||
1926 | static struct file_operations tracing_fops = { | |
4bf39a94 IM |
1927 | .open = tracing_open, |
1928 | .read = seq_read, | |
1929 | .llseek = seq_lseek, | |
1930 | .release = tracing_release, | |
bc0c38d1 SR |
1931 | }; |
1932 | ||
1933 | static struct file_operations tracing_lt_fops = { | |
4bf39a94 IM |
1934 | .open = tracing_lt_open, |
1935 | .read = seq_read, | |
1936 | .llseek = seq_lseek, | |
1937 | .release = tracing_release, | |
bc0c38d1 SR |
1938 | }; |
1939 | ||
1940 | static struct file_operations show_traces_fops = { | |
c7078de1 IM |
1941 | .open = show_traces_open, |
1942 | .read = seq_read, | |
1943 | .release = seq_release, | |
1944 | }; | |
1945 | ||
36dfe925 IM |
1946 | /* |
1947 | * Only trace on a CPU if the bitmask is set: | |
1948 | */ | |
1949 | static cpumask_t tracing_cpumask = CPU_MASK_ALL; | |
1950 | ||
1951 | /* | |
1952 | * When tracing/tracing_cpu_mask is modified then this holds | |
1953 | * the new bitmask we are about to install: | |
1954 | */ | |
1955 | static cpumask_t tracing_cpumask_new; | |
1956 | ||
1957 | /* | |
1958 | * The tracer itself will not take this lock, but still we want | |
1959 | * to provide a consistent cpumask to user-space: | |
1960 | */ | |
1961 | static DEFINE_MUTEX(tracing_cpumask_update_lock); | |
1962 | ||
1963 | /* | |
1964 | * Temporary storage for the character representation of the | |
1965 | * CPU bitmask (and one more byte for the newline): | |
1966 | */ | |
1967 | static char mask_str[NR_CPUS + 1]; | |
1968 | ||
c7078de1 IM |
1969 | static ssize_t |
1970 | tracing_cpumask_read(struct file *filp, char __user *ubuf, | |
1971 | size_t count, loff_t *ppos) | |
1972 | { | |
36dfe925 | 1973 | int len; |
c7078de1 IM |
1974 | |
1975 | mutex_lock(&tracing_cpumask_update_lock); | |
36dfe925 IM |
1976 | |
1977 | len = cpumask_scnprintf(mask_str, count, tracing_cpumask); | |
1978 | if (count - len < 2) { | |
1979 | count = -EINVAL; | |
1980 | goto out_err; | |
1981 | } | |
1982 | len += sprintf(mask_str + len, "\n"); | |
1983 | count = simple_read_from_buffer(ubuf, count, ppos, mask_str, NR_CPUS+1); | |
1984 | ||
1985 | out_err: | |
c7078de1 IM |
1986 | mutex_unlock(&tracing_cpumask_update_lock); |
1987 | ||
1988 | return count; | |
1989 | } | |
1990 | ||
1991 | static ssize_t | |
1992 | tracing_cpumask_write(struct file *filp, const char __user *ubuf, | |
1993 | size_t count, loff_t *ppos) | |
1994 | { | |
36dfe925 | 1995 | int err, cpu; |
c7078de1 IM |
1996 | |
1997 | mutex_lock(&tracing_cpumask_update_lock); | |
36dfe925 | 1998 | err = cpumask_parse_user(ubuf, count, tracing_cpumask_new); |
c7078de1 | 1999 | if (err) |
36dfe925 IM |
2000 | goto err_unlock; |
2001 | ||
92205c23 SR |
2002 | raw_local_irq_disable(); |
2003 | __raw_spin_lock(&ftrace_max_lock); | |
ab46428c | 2004 | for_each_tracing_cpu(cpu) { |
36dfe925 IM |
2005 | /* |
2006 | * Increase/decrease the disabled counter if we are | |
2007 | * about to flip a bit in the cpumask: | |
2008 | */ | |
2009 | if (cpu_isset(cpu, tracing_cpumask) && | |
2010 | !cpu_isset(cpu, tracing_cpumask_new)) { | |
2011 | atomic_inc(&global_trace.data[cpu]->disabled); | |
2012 | } | |
2013 | if (!cpu_isset(cpu, tracing_cpumask) && | |
2014 | cpu_isset(cpu, tracing_cpumask_new)) { | |
2015 | atomic_dec(&global_trace.data[cpu]->disabled); | |
2016 | } | |
2017 | } | |
92205c23 SR |
2018 | __raw_spin_unlock(&ftrace_max_lock); |
2019 | raw_local_irq_enable(); | |
36dfe925 IM |
2020 | |
2021 | tracing_cpumask = tracing_cpumask_new; | |
2022 | ||
2023 | mutex_unlock(&tracing_cpumask_update_lock); | |
c7078de1 IM |
2024 | |
2025 | return count; | |
36dfe925 IM |
2026 | |
2027 | err_unlock: | |
2028 | mutex_unlock(&tracing_cpumask_update_lock); | |
2029 | ||
2030 | return err; | |
c7078de1 IM |
2031 | } |
2032 | ||
2033 | static struct file_operations tracing_cpumask_fops = { | |
2034 | .open = tracing_open_generic, | |
2035 | .read = tracing_cpumask_read, | |
2036 | .write = tracing_cpumask_write, | |
bc0c38d1 SR |
2037 | }; |
2038 | ||
2039 | static ssize_t | |
2040 | tracing_iter_ctrl_read(struct file *filp, char __user *ubuf, | |
2041 | size_t cnt, loff_t *ppos) | |
2042 | { | |
2043 | char *buf; | |
2044 | int r = 0; | |
2045 | int len = 0; | |
2046 | int i; | |
2047 | ||
2048 | /* calulate max size */ | |
2049 | for (i = 0; trace_options[i]; i++) { | |
2050 | len += strlen(trace_options[i]); | |
2051 | len += 3; /* "no" and space */ | |
2052 | } | |
2053 | ||
2054 | /* +2 for \n and \0 */ | |
2055 | buf = kmalloc(len + 2, GFP_KERNEL); | |
2056 | if (!buf) | |
2057 | return -ENOMEM; | |
2058 | ||
2059 | for (i = 0; trace_options[i]; i++) { | |
2060 | if (trace_flags & (1 << i)) | |
2061 | r += sprintf(buf + r, "%s ", trace_options[i]); | |
2062 | else | |
2063 | r += sprintf(buf + r, "no%s ", trace_options[i]); | |
2064 | } | |
2065 | ||
2066 | r += sprintf(buf + r, "\n"); | |
2067 | WARN_ON(r >= len + 2); | |
2068 | ||
36dfe925 | 2069 | r = simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
2070 | |
2071 | kfree(buf); | |
2072 | ||
2073 | return r; | |
2074 | } | |
2075 | ||
2076 | static ssize_t | |
2077 | tracing_iter_ctrl_write(struct file *filp, const char __user *ubuf, | |
2078 | size_t cnt, loff_t *ppos) | |
2079 | { | |
2080 | char buf[64]; | |
2081 | char *cmp = buf; | |
2082 | int neg = 0; | |
2083 | int i; | |
2084 | ||
cffae437 SR |
2085 | if (cnt >= sizeof(buf)) |
2086 | return -EINVAL; | |
bc0c38d1 SR |
2087 | |
2088 | if (copy_from_user(&buf, ubuf, cnt)) | |
2089 | return -EFAULT; | |
2090 | ||
2091 | buf[cnt] = 0; | |
2092 | ||
2093 | if (strncmp(buf, "no", 2) == 0) { | |
2094 | neg = 1; | |
2095 | cmp += 2; | |
2096 | } | |
2097 | ||
2098 | for (i = 0; trace_options[i]; i++) { | |
2099 | int len = strlen(trace_options[i]); | |
2100 | ||
2101 | if (strncmp(cmp, trace_options[i], len) == 0) { | |
2102 | if (neg) | |
2103 | trace_flags &= ~(1 << i); | |
2104 | else | |
2105 | trace_flags |= (1 << i); | |
2106 | break; | |
2107 | } | |
2108 | } | |
442e544c IM |
2109 | /* |
2110 | * If no option could be set, return an error: | |
2111 | */ | |
2112 | if (!trace_options[i]) | |
2113 | return -EINVAL; | |
bc0c38d1 SR |
2114 | |
2115 | filp->f_pos += cnt; | |
2116 | ||
2117 | return cnt; | |
2118 | } | |
2119 | ||
2120 | static struct file_operations tracing_iter_fops = { | |
c7078de1 IM |
2121 | .open = tracing_open_generic, |
2122 | .read = tracing_iter_ctrl_read, | |
2123 | .write = tracing_iter_ctrl_write, | |
bc0c38d1 SR |
2124 | }; |
2125 | ||
7bd2f24c IM |
2126 | static const char readme_msg[] = |
2127 | "tracing mini-HOWTO:\n\n" | |
2128 | "# mkdir /debug\n" | |
2129 | "# mount -t debugfs nodev /debug\n\n" | |
2130 | "# cat /debug/tracing/available_tracers\n" | |
2131 | "wakeup preemptirqsoff preemptoff irqsoff ftrace sched_switch none\n\n" | |
2132 | "# cat /debug/tracing/current_tracer\n" | |
2133 | "none\n" | |
2134 | "# echo sched_switch > /debug/tracing/current_tracer\n" | |
2135 | "# cat /debug/tracing/current_tracer\n" | |
2136 | "sched_switch\n" | |
2137 | "# cat /debug/tracing/iter_ctrl\n" | |
2138 | "noprint-parent nosym-offset nosym-addr noverbose\n" | |
2139 | "# echo print-parent > /debug/tracing/iter_ctrl\n" | |
2140 | "# echo 1 > /debug/tracing/tracing_enabled\n" | |
2141 | "# cat /debug/tracing/trace > /tmp/trace.txt\n" | |
2142 | "echo 0 > /debug/tracing/tracing_enabled\n" | |
2143 | ; | |
2144 | ||
2145 | static ssize_t | |
2146 | tracing_readme_read(struct file *filp, char __user *ubuf, | |
2147 | size_t cnt, loff_t *ppos) | |
2148 | { | |
2149 | return simple_read_from_buffer(ubuf, cnt, ppos, | |
2150 | readme_msg, strlen(readme_msg)); | |
2151 | } | |
2152 | ||
2153 | static struct file_operations tracing_readme_fops = { | |
c7078de1 IM |
2154 | .open = tracing_open_generic, |
2155 | .read = tracing_readme_read, | |
7bd2f24c IM |
2156 | }; |
2157 | ||
bc0c38d1 SR |
2158 | static ssize_t |
2159 | tracing_ctrl_read(struct file *filp, char __user *ubuf, | |
2160 | size_t cnt, loff_t *ppos) | |
2161 | { | |
2162 | struct trace_array *tr = filp->private_data; | |
2163 | char buf[64]; | |
2164 | int r; | |
2165 | ||
2166 | r = sprintf(buf, "%ld\n", tr->ctrl); | |
4e3c3333 | 2167 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
2168 | } |
2169 | ||
2170 | static ssize_t | |
2171 | tracing_ctrl_write(struct file *filp, const char __user *ubuf, | |
2172 | size_t cnt, loff_t *ppos) | |
2173 | { | |
2174 | struct trace_array *tr = filp->private_data; | |
bc0c38d1 | 2175 | char buf[64]; |
c6caeeb1 SR |
2176 | long val; |
2177 | int ret; | |
bc0c38d1 | 2178 | |
cffae437 SR |
2179 | if (cnt >= sizeof(buf)) |
2180 | return -EINVAL; | |
bc0c38d1 SR |
2181 | |
2182 | if (copy_from_user(&buf, ubuf, cnt)) | |
2183 | return -EFAULT; | |
2184 | ||
2185 | buf[cnt] = 0; | |
2186 | ||
c6caeeb1 SR |
2187 | ret = strict_strtoul(buf, 10, &val); |
2188 | if (ret < 0) | |
2189 | return ret; | |
bc0c38d1 SR |
2190 | |
2191 | val = !!val; | |
2192 | ||
2193 | mutex_lock(&trace_types_lock); | |
2194 | if (tr->ctrl ^ val) { | |
2195 | if (val) | |
2196 | tracer_enabled = 1; | |
2197 | else | |
2198 | tracer_enabled = 0; | |
2199 | ||
2200 | tr->ctrl = val; | |
2201 | ||
2202 | if (current_trace && current_trace->ctrl_update) | |
2203 | current_trace->ctrl_update(tr); | |
2204 | } | |
2205 | mutex_unlock(&trace_types_lock); | |
2206 | ||
2207 | filp->f_pos += cnt; | |
2208 | ||
2209 | return cnt; | |
2210 | } | |
2211 | ||
2212 | static ssize_t | |
2213 | tracing_set_trace_read(struct file *filp, char __user *ubuf, | |
2214 | size_t cnt, loff_t *ppos) | |
2215 | { | |
2216 | char buf[max_tracer_type_len+2]; | |
2217 | int r; | |
2218 | ||
2219 | mutex_lock(&trace_types_lock); | |
2220 | if (current_trace) | |
2221 | r = sprintf(buf, "%s\n", current_trace->name); | |
2222 | else | |
2223 | r = sprintf(buf, "\n"); | |
2224 | mutex_unlock(&trace_types_lock); | |
2225 | ||
4bf39a94 | 2226 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
2227 | } |
2228 | ||
2229 | static ssize_t | |
2230 | tracing_set_trace_write(struct file *filp, const char __user *ubuf, | |
2231 | size_t cnt, loff_t *ppos) | |
2232 | { | |
2233 | struct trace_array *tr = &global_trace; | |
2234 | struct tracer *t; | |
2235 | char buf[max_tracer_type_len+1]; | |
2236 | int i; | |
2237 | ||
2238 | if (cnt > max_tracer_type_len) | |
2239 | cnt = max_tracer_type_len; | |
2240 | ||
2241 | if (copy_from_user(&buf, ubuf, cnt)) | |
2242 | return -EFAULT; | |
2243 | ||
2244 | buf[cnt] = 0; | |
2245 | ||
2246 | /* strip ending whitespace. */ | |
2247 | for (i = cnt - 1; i > 0 && isspace(buf[i]); i--) | |
2248 | buf[i] = 0; | |
2249 | ||
2250 | mutex_lock(&trace_types_lock); | |
2251 | for (t = trace_types; t; t = t->next) { | |
2252 | if (strcmp(t->name, buf) == 0) | |
2253 | break; | |
2254 | } | |
2255 | if (!t || t == current_trace) | |
2256 | goto out; | |
2257 | ||
2258 | if (current_trace && current_trace->reset) | |
2259 | current_trace->reset(tr); | |
2260 | ||
2261 | current_trace = t; | |
2262 | if (t->init) | |
2263 | t->init(tr); | |
2264 | ||
2265 | out: | |
2266 | mutex_unlock(&trace_types_lock); | |
2267 | ||
2268 | filp->f_pos += cnt; | |
2269 | ||
2270 | return cnt; | |
2271 | } | |
2272 | ||
2273 | static ssize_t | |
2274 | tracing_max_lat_read(struct file *filp, char __user *ubuf, | |
2275 | size_t cnt, loff_t *ppos) | |
2276 | { | |
2277 | unsigned long *ptr = filp->private_data; | |
2278 | char buf[64]; | |
2279 | int r; | |
2280 | ||
cffae437 | 2281 | r = snprintf(buf, sizeof(buf), "%ld\n", |
bc0c38d1 | 2282 | *ptr == (unsigned long)-1 ? -1 : nsecs_to_usecs(*ptr)); |
cffae437 SR |
2283 | if (r > sizeof(buf)) |
2284 | r = sizeof(buf); | |
4bf39a94 | 2285 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); |
bc0c38d1 SR |
2286 | } |
2287 | ||
2288 | static ssize_t | |
2289 | tracing_max_lat_write(struct file *filp, const char __user *ubuf, | |
2290 | size_t cnt, loff_t *ppos) | |
2291 | { | |
2292 | long *ptr = filp->private_data; | |
bc0c38d1 | 2293 | char buf[64]; |
c6caeeb1 SR |
2294 | long val; |
2295 | int ret; | |
bc0c38d1 | 2296 | |
cffae437 SR |
2297 | if (cnt >= sizeof(buf)) |
2298 | return -EINVAL; | |
bc0c38d1 SR |
2299 | |
2300 | if (copy_from_user(&buf, ubuf, cnt)) | |
2301 | return -EFAULT; | |
2302 | ||
2303 | buf[cnt] = 0; | |
2304 | ||
c6caeeb1 SR |
2305 | ret = strict_strtoul(buf, 10, &val); |
2306 | if (ret < 0) | |
2307 | return ret; | |
bc0c38d1 SR |
2308 | |
2309 | *ptr = val * 1000; | |
2310 | ||
2311 | return cnt; | |
2312 | } | |
2313 | ||
b3806b43 SR |
2314 | static atomic_t tracing_reader; |
2315 | ||
2316 | static int tracing_open_pipe(struct inode *inode, struct file *filp) | |
2317 | { | |
2318 | struct trace_iterator *iter; | |
2319 | ||
2320 | if (tracing_disabled) | |
2321 | return -ENODEV; | |
2322 | ||
2323 | /* We only allow for reader of the pipe */ | |
2324 | if (atomic_inc_return(&tracing_reader) != 1) { | |
2325 | atomic_dec(&tracing_reader); | |
2326 | return -EBUSY; | |
2327 | } | |
2328 | ||
2329 | /* create a buffer to store the information to pass to userspace */ | |
2330 | iter = kzalloc(sizeof(*iter), GFP_KERNEL); | |
2331 | if (!iter) | |
2332 | return -ENOMEM; | |
2333 | ||
107bad8b | 2334 | mutex_lock(&trace_types_lock); |
b3806b43 | 2335 | iter->tr = &global_trace; |
72829bc3 | 2336 | iter->trace = current_trace; |
b3806b43 SR |
2337 | filp->private_data = iter; |
2338 | ||
107bad8b SR |
2339 | if (iter->trace->pipe_open) |
2340 | iter->trace->pipe_open(iter); | |
2341 | mutex_unlock(&trace_types_lock); | |
2342 | ||
b3806b43 SR |
2343 | return 0; |
2344 | } | |
2345 | ||
2346 | static int tracing_release_pipe(struct inode *inode, struct file *file) | |
2347 | { | |
2348 | struct trace_iterator *iter = file->private_data; | |
2349 | ||
2350 | kfree(iter); | |
2351 | atomic_dec(&tracing_reader); | |
2352 | ||
2353 | return 0; | |
2354 | } | |
2355 | ||
2a2cc8f7 SSP |
2356 | static unsigned int |
2357 | tracing_poll_pipe(struct file *filp, poll_table *poll_table) | |
2358 | { | |
2359 | struct trace_iterator *iter = filp->private_data; | |
2360 | ||
2361 | if (trace_flags & TRACE_ITER_BLOCK) { | |
2362 | /* | |
2363 | * Always select as readable when in blocking mode | |
2364 | */ | |
2365 | return POLLIN | POLLRDNORM; | |
afc2abc0 | 2366 | } else { |
2a2cc8f7 SSP |
2367 | if (!trace_empty(iter)) |
2368 | return POLLIN | POLLRDNORM; | |
2369 | poll_wait(filp, &trace_wait, poll_table); | |
2370 | if (!trace_empty(iter)) | |
2371 | return POLLIN | POLLRDNORM; | |
2372 | ||
2373 | return 0; | |
2374 | } | |
2375 | } | |
2376 | ||
b3806b43 SR |
2377 | /* |
2378 | * Consumer reader. | |
2379 | */ | |
2380 | static ssize_t | |
2381 | tracing_read_pipe(struct file *filp, char __user *ubuf, | |
2382 | size_t cnt, loff_t *ppos) | |
2383 | { | |
2384 | struct trace_iterator *iter = filp->private_data; | |
2385 | struct trace_array_cpu *data; | |
2386 | static cpumask_t mask; | |
b3806b43 | 2387 | unsigned long flags; |
25770467 | 2388 | #ifdef CONFIG_FTRACE |
2e0f5761 | 2389 | int ftrace_save; |
25770467 | 2390 | #endif |
b3806b43 | 2391 | int cpu; |
6c6c2796 | 2392 | ssize_t sret; |
b3806b43 SR |
2393 | |
2394 | /* return any leftover data */ | |
6c6c2796 PP |
2395 | sret = trace_seq_to_user(&iter->seq, ubuf, cnt); |
2396 | if (sret != -EBUSY) | |
2397 | return sret; | |
2398 | sret = 0; | |
b3806b43 | 2399 | |
6c6c2796 | 2400 | trace_seq_reset(&iter->seq); |
b3806b43 | 2401 | |
107bad8b SR |
2402 | mutex_lock(&trace_types_lock); |
2403 | if (iter->trace->read) { | |
6c6c2796 PP |
2404 | sret = iter->trace->read(iter, filp, ubuf, cnt, ppos); |
2405 | if (sret) | |
107bad8b | 2406 | goto out; |
107bad8b SR |
2407 | } |
2408 | ||
b3806b43 | 2409 | while (trace_empty(iter)) { |
2dc8f095 | 2410 | |
107bad8b | 2411 | if ((filp->f_flags & O_NONBLOCK)) { |
6c6c2796 | 2412 | sret = -EAGAIN; |
107bad8b SR |
2413 | goto out; |
2414 | } | |
2dc8f095 | 2415 | |
b3806b43 SR |
2416 | /* |
2417 | * This is a make-shift waitqueue. The reason we don't use | |
2418 | * an actual wait queue is because: | |
2419 | * 1) we only ever have one waiter | |
2420 | * 2) the tracing, traces all functions, we don't want | |
2421 | * the overhead of calling wake_up and friends | |
2422 | * (and tracing them too) | |
2423 | * Anyway, this is really very primitive wakeup. | |
2424 | */ | |
2425 | set_current_state(TASK_INTERRUPTIBLE); | |
2426 | iter->tr->waiter = current; | |
2427 | ||
107bad8b SR |
2428 | mutex_unlock(&trace_types_lock); |
2429 | ||
9fe068e9 IM |
2430 | /* sleep for 100 msecs, and try again. */ |
2431 | schedule_timeout(HZ/10); | |
b3806b43 | 2432 | |
107bad8b SR |
2433 | mutex_lock(&trace_types_lock); |
2434 | ||
b3806b43 SR |
2435 | iter->tr->waiter = NULL; |
2436 | ||
107bad8b | 2437 | if (signal_pending(current)) { |
6c6c2796 | 2438 | sret = -EINTR; |
107bad8b SR |
2439 | goto out; |
2440 | } | |
b3806b43 | 2441 | |
84527997 | 2442 | if (iter->trace != current_trace) |
107bad8b | 2443 | goto out; |
84527997 | 2444 | |
b3806b43 SR |
2445 | /* |
2446 | * We block until we read something and tracing is disabled. | |
2447 | * We still block if tracing is disabled, but we have never | |
2448 | * read anything. This allows a user to cat this file, and | |
2449 | * then enable tracing. But after we have read something, | |
2450 | * we give an EOF when tracing is again disabled. | |
2451 | * | |
2452 | * iter->pos will be 0 if we haven't read anything. | |
2453 | */ | |
2454 | if (!tracer_enabled && iter->pos) | |
2455 | break; | |
2456 | ||
2457 | continue; | |
2458 | } | |
2459 | ||
2460 | /* stop when tracing is finished */ | |
2461 | if (trace_empty(iter)) | |
107bad8b | 2462 | goto out; |
b3806b43 SR |
2463 | |
2464 | if (cnt >= PAGE_SIZE) | |
2465 | cnt = PAGE_SIZE - 1; | |
2466 | ||
53d0aa77 | 2467 | /* reset all but tr, trace, and overruns */ |
53d0aa77 SR |
2468 | memset(&iter->seq, 0, |
2469 | sizeof(struct trace_iterator) - | |
2470 | offsetof(struct trace_iterator, seq)); | |
4823ed7e | 2471 | iter->pos = -1; |
b3806b43 SR |
2472 | |
2473 | /* | |
2474 | * We need to stop all tracing on all CPUS to read the | |
2475 | * the next buffer. This is a bit expensive, but is | |
2476 | * not done often. We fill all what we can read, | |
2477 | * and then release the locks again. | |
2478 | */ | |
2479 | ||
2480 | cpus_clear(mask); | |
2481 | local_irq_save(flags); | |
25770467 | 2482 | #ifdef CONFIG_FTRACE |
2e0f5761 IM |
2483 | ftrace_save = ftrace_enabled; |
2484 | ftrace_enabled = 0; | |
25770467 | 2485 | #endif |
2e0f5761 | 2486 | smp_wmb(); |
ab46428c | 2487 | for_each_tracing_cpu(cpu) { |
b3806b43 SR |
2488 | data = iter->tr->data[cpu]; |
2489 | ||
2490 | if (!head_page(data) || !data->trace_idx) | |
2491 | continue; | |
2492 | ||
2493 | atomic_inc(&data->disabled); | |
b3806b43 SR |
2494 | cpu_set(cpu, mask); |
2495 | } | |
2496 | ||
2e0f5761 IM |
2497 | for_each_cpu_mask(cpu, mask) { |
2498 | data = iter->tr->data[cpu]; | |
92205c23 | 2499 | __raw_spin_lock(&data->lock); |
53d0aa77 SR |
2500 | |
2501 | if (data->overrun > iter->last_overrun[cpu]) | |
2502 | iter->overrun[cpu] += | |
2503 | data->overrun - iter->last_overrun[cpu]; | |
2504 | iter->last_overrun[cpu] = data->overrun; | |
2e0f5761 IM |
2505 | } |
2506 | ||
088b1e42 | 2507 | while (find_next_entry_inc(iter) != NULL) { |
6c6c2796 | 2508 | int ret; |
088b1e42 SR |
2509 | int len = iter->seq.len; |
2510 | ||
f9896bf3 | 2511 | ret = print_trace_line(iter); |
088b1e42 SR |
2512 | if (!ret) { |
2513 | /* don't print partial lines */ | |
2514 | iter->seq.len = len; | |
b3806b43 | 2515 | break; |
088b1e42 | 2516 | } |
b3806b43 SR |
2517 | |
2518 | trace_consume(iter); | |
2519 | ||
2520 | if (iter->seq.len >= cnt) | |
2521 | break; | |
b3806b43 SR |
2522 | } |
2523 | ||
d4c5a2f5 | 2524 | for_each_cpu_mask(cpu, mask) { |
b3806b43 | 2525 | data = iter->tr->data[cpu]; |
92205c23 | 2526 | __raw_spin_unlock(&data->lock); |
2e0f5761 IM |
2527 | } |
2528 | ||
2529 | for_each_cpu_mask(cpu, mask) { | |
2530 | data = iter->tr->data[cpu]; | |
b3806b43 SR |
2531 | atomic_dec(&data->disabled); |
2532 | } | |
25770467 | 2533 | #ifdef CONFIG_FTRACE |
2e0f5761 | 2534 | ftrace_enabled = ftrace_save; |
25770467 | 2535 | #endif |
b3806b43 SR |
2536 | local_irq_restore(flags); |
2537 | ||
2538 | /* Now copy what we have to the user */ | |
6c6c2796 PP |
2539 | sret = trace_seq_to_user(&iter->seq, ubuf, cnt); |
2540 | if (iter->seq.readpos >= iter->seq.len) | |
b3806b43 | 2541 | trace_seq_reset(&iter->seq); |
6c6c2796 PP |
2542 | if (sret == -EBUSY) |
2543 | sret = 0; | |
b3806b43 | 2544 | |
107bad8b SR |
2545 | out: |
2546 | mutex_unlock(&trace_types_lock); | |
2547 | ||
6c6c2796 | 2548 | return sret; |
b3806b43 SR |
2549 | } |
2550 | ||
a98a3c3f SR |
2551 | static ssize_t |
2552 | tracing_entries_read(struct file *filp, char __user *ubuf, | |
2553 | size_t cnt, loff_t *ppos) | |
2554 | { | |
2555 | struct trace_array *tr = filp->private_data; | |
2556 | char buf[64]; | |
2557 | int r; | |
2558 | ||
2559 | r = sprintf(buf, "%lu\n", tr->entries); | |
2560 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
2561 | } | |
2562 | ||
2563 | static ssize_t | |
2564 | tracing_entries_write(struct file *filp, const char __user *ubuf, | |
2565 | size_t cnt, loff_t *ppos) | |
2566 | { | |
2567 | unsigned long val; | |
2568 | char buf[64]; | |
c6caeeb1 | 2569 | int ret; |
a98a3c3f | 2570 | |
cffae437 SR |
2571 | if (cnt >= sizeof(buf)) |
2572 | return -EINVAL; | |
a98a3c3f SR |
2573 | |
2574 | if (copy_from_user(&buf, ubuf, cnt)) | |
2575 | return -EFAULT; | |
2576 | ||
2577 | buf[cnt] = 0; | |
2578 | ||
c6caeeb1 SR |
2579 | ret = strict_strtoul(buf, 10, &val); |
2580 | if (ret < 0) | |
2581 | return ret; | |
a98a3c3f SR |
2582 | |
2583 | /* must have at least 1 entry */ | |
2584 | if (!val) | |
2585 | return -EINVAL; | |
2586 | ||
2587 | mutex_lock(&trace_types_lock); | |
2588 | ||
2589 | if (current_trace != &no_tracer) { | |
2590 | cnt = -EBUSY; | |
2591 | pr_info("ftrace: set current_tracer to none" | |
2592 | " before modifying buffer size\n"); | |
2593 | goto out; | |
2594 | } | |
2595 | ||
2596 | if (val > global_trace.entries) { | |
3eefae99 SR |
2597 | long pages_requested; |
2598 | unsigned long freeable_pages; | |
2599 | ||
2600 | /* make sure we have enough memory before mapping */ | |
2601 | pages_requested = | |
2602 | (val + (ENTRIES_PER_PAGE-1)) / ENTRIES_PER_PAGE; | |
2603 | ||
2604 | /* account for each buffer (and max_tr) */ | |
2605 | pages_requested *= tracing_nr_buffers * 2; | |
2606 | ||
2607 | /* Check for overflow */ | |
2608 | if (pages_requested < 0) { | |
2609 | cnt = -ENOMEM; | |
2610 | goto out; | |
2611 | } | |
2612 | ||
2613 | freeable_pages = determine_dirtyable_memory(); | |
2614 | ||
2615 | /* we only allow to request 1/4 of useable memory */ | |
2616 | if (pages_requested > | |
2617 | ((freeable_pages + tracing_pages_allocated) / 4)) { | |
2618 | cnt = -ENOMEM; | |
2619 | goto out; | |
2620 | } | |
2621 | ||
a98a3c3f SR |
2622 | while (global_trace.entries < val) { |
2623 | if (trace_alloc_page()) { | |
2624 | cnt = -ENOMEM; | |
2625 | goto out; | |
2626 | } | |
3eefae99 SR |
2627 | /* double check that we don't go over the known pages */ |
2628 | if (tracing_pages_allocated > pages_requested) | |
2629 | break; | |
a98a3c3f | 2630 | } |
3eefae99 | 2631 | |
a98a3c3f SR |
2632 | } else { |
2633 | /* include the number of entries in val (inc of page entries) */ | |
2634 | while (global_trace.entries > val + (ENTRIES_PER_PAGE - 1)) | |
2635 | trace_free_page(); | |
2636 | } | |
2637 | ||
2638 | filp->f_pos += cnt; | |
2639 | ||
2640 | out: | |
2641 | max_tr.entries = global_trace.entries; | |
2642 | mutex_unlock(&trace_types_lock); | |
2643 | ||
2644 | return cnt; | |
2645 | } | |
2646 | ||
bc0c38d1 | 2647 | static struct file_operations tracing_max_lat_fops = { |
4bf39a94 IM |
2648 | .open = tracing_open_generic, |
2649 | .read = tracing_max_lat_read, | |
2650 | .write = tracing_max_lat_write, | |
bc0c38d1 SR |
2651 | }; |
2652 | ||
2653 | static struct file_operations tracing_ctrl_fops = { | |
4bf39a94 IM |
2654 | .open = tracing_open_generic, |
2655 | .read = tracing_ctrl_read, | |
2656 | .write = tracing_ctrl_write, | |
bc0c38d1 SR |
2657 | }; |
2658 | ||
2659 | static struct file_operations set_tracer_fops = { | |
4bf39a94 IM |
2660 | .open = tracing_open_generic, |
2661 | .read = tracing_set_trace_read, | |
2662 | .write = tracing_set_trace_write, | |
bc0c38d1 SR |
2663 | }; |
2664 | ||
b3806b43 | 2665 | static struct file_operations tracing_pipe_fops = { |
4bf39a94 | 2666 | .open = tracing_open_pipe, |
2a2cc8f7 | 2667 | .poll = tracing_poll_pipe, |
4bf39a94 IM |
2668 | .read = tracing_read_pipe, |
2669 | .release = tracing_release_pipe, | |
b3806b43 SR |
2670 | }; |
2671 | ||
a98a3c3f SR |
2672 | static struct file_operations tracing_entries_fops = { |
2673 | .open = tracing_open_generic, | |
2674 | .read = tracing_entries_read, | |
2675 | .write = tracing_entries_write, | |
2676 | }; | |
2677 | ||
bc0c38d1 SR |
2678 | #ifdef CONFIG_DYNAMIC_FTRACE |
2679 | ||
2680 | static ssize_t | |
2681 | tracing_read_long(struct file *filp, char __user *ubuf, | |
2682 | size_t cnt, loff_t *ppos) | |
2683 | { | |
2684 | unsigned long *p = filp->private_data; | |
2685 | char buf[64]; | |
2686 | int r; | |
2687 | ||
2688 | r = sprintf(buf, "%ld\n", *p); | |
4bf39a94 IM |
2689 | |
2690 | return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); | |
bc0c38d1 SR |
2691 | } |
2692 | ||
2693 | static struct file_operations tracing_read_long_fops = { | |
4bf39a94 IM |
2694 | .open = tracing_open_generic, |
2695 | .read = tracing_read_long, | |
bc0c38d1 SR |
2696 | }; |
2697 | #endif | |
2698 | ||
2699 | static struct dentry *d_tracer; | |
2700 | ||
2701 | struct dentry *tracing_init_dentry(void) | |
2702 | { | |
2703 | static int once; | |
2704 | ||
2705 | if (d_tracer) | |
2706 | return d_tracer; | |
2707 | ||
2708 | d_tracer = debugfs_create_dir("tracing", NULL); | |
2709 | ||
2710 | if (!d_tracer && !once) { | |
2711 | once = 1; | |
2712 | pr_warning("Could not create debugfs directory 'tracing'\n"); | |
2713 | return NULL; | |
2714 | } | |
2715 | ||
2716 | return d_tracer; | |
2717 | } | |
2718 | ||
60a11774 SR |
2719 | #ifdef CONFIG_FTRACE_SELFTEST |
2720 | /* Let selftest have access to static functions in this file */ | |
2721 | #include "trace_selftest.c" | |
2722 | #endif | |
2723 | ||
bc0c38d1 SR |
2724 | static __init void tracer_init_debugfs(void) |
2725 | { | |
2726 | struct dentry *d_tracer; | |
2727 | struct dentry *entry; | |
2728 | ||
2729 | d_tracer = tracing_init_dentry(); | |
2730 | ||
2731 | entry = debugfs_create_file("tracing_enabled", 0644, d_tracer, | |
2732 | &global_trace, &tracing_ctrl_fops); | |
2733 | if (!entry) | |
2734 | pr_warning("Could not create debugfs 'tracing_enabled' entry\n"); | |
2735 | ||
2736 | entry = debugfs_create_file("iter_ctrl", 0644, d_tracer, | |
2737 | NULL, &tracing_iter_fops); | |
2738 | if (!entry) | |
2739 | pr_warning("Could not create debugfs 'iter_ctrl' entry\n"); | |
2740 | ||
c7078de1 IM |
2741 | entry = debugfs_create_file("tracing_cpumask", 0644, d_tracer, |
2742 | NULL, &tracing_cpumask_fops); | |
2743 | if (!entry) | |
2744 | pr_warning("Could not create debugfs 'tracing_cpumask' entry\n"); | |
2745 | ||
bc0c38d1 SR |
2746 | entry = debugfs_create_file("latency_trace", 0444, d_tracer, |
2747 | &global_trace, &tracing_lt_fops); | |
2748 | if (!entry) | |
2749 | pr_warning("Could not create debugfs 'latency_trace' entry\n"); | |
2750 | ||
2751 | entry = debugfs_create_file("trace", 0444, d_tracer, | |
2752 | &global_trace, &tracing_fops); | |
2753 | if (!entry) | |
2754 | pr_warning("Could not create debugfs 'trace' entry\n"); | |
2755 | ||
2756 | entry = debugfs_create_file("available_tracers", 0444, d_tracer, | |
2757 | &global_trace, &show_traces_fops); | |
2758 | if (!entry) | |
2759 | pr_warning("Could not create debugfs 'trace' entry\n"); | |
2760 | ||
2761 | entry = debugfs_create_file("current_tracer", 0444, d_tracer, | |
2762 | &global_trace, &set_tracer_fops); | |
2763 | if (!entry) | |
2764 | pr_warning("Could not create debugfs 'trace' entry\n"); | |
2765 | ||
2766 | entry = debugfs_create_file("tracing_max_latency", 0644, d_tracer, | |
2767 | &tracing_max_latency, | |
2768 | &tracing_max_lat_fops); | |
2769 | if (!entry) | |
2770 | pr_warning("Could not create debugfs " | |
2771 | "'tracing_max_latency' entry\n"); | |
2772 | ||
2773 | entry = debugfs_create_file("tracing_thresh", 0644, d_tracer, | |
2774 | &tracing_thresh, &tracing_max_lat_fops); | |
2775 | if (!entry) | |
2776 | pr_warning("Could not create debugfs " | |
2777 | "'tracing_threash' entry\n"); | |
7bd2f24c IM |
2778 | entry = debugfs_create_file("README", 0644, d_tracer, |
2779 | NULL, &tracing_readme_fops); | |
2780 | if (!entry) | |
2781 | pr_warning("Could not create debugfs 'README' entry\n"); | |
2782 | ||
b3806b43 SR |
2783 | entry = debugfs_create_file("trace_pipe", 0644, d_tracer, |
2784 | NULL, &tracing_pipe_fops); | |
2785 | if (!entry) | |
2786 | pr_warning("Could not create debugfs " | |
2787 | "'tracing_threash' entry\n"); | |
bc0c38d1 | 2788 | |
a98a3c3f SR |
2789 | entry = debugfs_create_file("trace_entries", 0644, d_tracer, |
2790 | &global_trace, &tracing_entries_fops); | |
2791 | if (!entry) | |
2792 | pr_warning("Could not create debugfs " | |
2793 | "'tracing_threash' entry\n"); | |
2794 | ||
bc0c38d1 SR |
2795 | #ifdef CONFIG_DYNAMIC_FTRACE |
2796 | entry = debugfs_create_file("dyn_ftrace_total_info", 0444, d_tracer, | |
2797 | &ftrace_update_tot_cnt, | |
2798 | &tracing_read_long_fops); | |
2799 | if (!entry) | |
2800 | pr_warning("Could not create debugfs " | |
2801 | "'dyn_ftrace_total_info' entry\n"); | |
2802 | #endif | |
2803 | } | |
2804 | ||
4c11d7ae | 2805 | static int trace_alloc_page(void) |
bc0c38d1 | 2806 | { |
4c11d7ae | 2807 | struct trace_array_cpu *data; |
4c11d7ae SR |
2808 | struct page *page, *tmp; |
2809 | LIST_HEAD(pages); | |
c7aafc54 | 2810 | void *array; |
3eefae99 | 2811 | unsigned pages_allocated = 0; |
4c11d7ae SR |
2812 | int i; |
2813 | ||
2814 | /* first allocate a page for each CPU */ | |
ab46428c | 2815 | for_each_tracing_cpu(i) { |
4c11d7ae SR |
2816 | array = (void *)__get_free_page(GFP_KERNEL); |
2817 | if (array == NULL) { | |
2818 | printk(KERN_ERR "tracer: failed to allocate page" | |
2819 | "for trace buffer!\n"); | |
2820 | goto free_pages; | |
2821 | } | |
2822 | ||
3eefae99 | 2823 | pages_allocated++; |
4c11d7ae SR |
2824 | page = virt_to_page(array); |
2825 | list_add(&page->lru, &pages); | |
2826 | ||
2827 | /* Only allocate if we are actually using the max trace */ | |
2828 | #ifdef CONFIG_TRACER_MAX_TRACE | |
2829 | array = (void *)__get_free_page(GFP_KERNEL); | |
2830 | if (array == NULL) { | |
2831 | printk(KERN_ERR "tracer: failed to allocate page" | |
2832 | "for trace buffer!\n"); | |
2833 | goto free_pages; | |
2834 | } | |
3eefae99 | 2835 | pages_allocated++; |
4c11d7ae SR |
2836 | page = virt_to_page(array); |
2837 | list_add(&page->lru, &pages); | |
2838 | #endif | |
2839 | } | |
2840 | ||
2841 | /* Now that we successfully allocate a page per CPU, add them */ | |
ab46428c | 2842 | for_each_tracing_cpu(i) { |
4c11d7ae SR |
2843 | data = global_trace.data[i]; |
2844 | page = list_entry(pages.next, struct page, lru); | |
c7aafc54 | 2845 | list_del_init(&page->lru); |
4c11d7ae SR |
2846 | list_add_tail(&page->lru, &data->trace_pages); |
2847 | ClearPageLRU(page); | |
2848 | ||
2849 | #ifdef CONFIG_TRACER_MAX_TRACE | |
2850 | data = max_tr.data[i]; | |
2851 | page = list_entry(pages.next, struct page, lru); | |
c7aafc54 | 2852 | list_del_init(&page->lru); |
4c11d7ae SR |
2853 | list_add_tail(&page->lru, &data->trace_pages); |
2854 | SetPageLRU(page); | |
2855 | #endif | |
2856 | } | |
3eefae99 | 2857 | tracing_pages_allocated += pages_allocated; |
4c11d7ae SR |
2858 | global_trace.entries += ENTRIES_PER_PAGE; |
2859 | ||
2860 | return 0; | |
2861 | ||
2862 | free_pages: | |
2863 | list_for_each_entry_safe(page, tmp, &pages, lru) { | |
c7aafc54 | 2864 | list_del_init(&page->lru); |
4c11d7ae SR |
2865 | __free_page(page); |
2866 | } | |
2867 | return -ENOMEM; | |
bc0c38d1 SR |
2868 | } |
2869 | ||
a98a3c3f SR |
2870 | static int trace_free_page(void) |
2871 | { | |
2872 | struct trace_array_cpu *data; | |
2873 | struct page *page; | |
2874 | struct list_head *p; | |
2875 | int i; | |
2876 | int ret = 0; | |
2877 | ||
2878 | /* free one page from each buffer */ | |
ab46428c | 2879 | for_each_tracing_cpu(i) { |
a98a3c3f SR |
2880 | data = global_trace.data[i]; |
2881 | p = data->trace_pages.next; | |
2882 | if (p == &data->trace_pages) { | |
2883 | /* should never happen */ | |
2884 | WARN_ON(1); | |
2885 | tracing_disabled = 1; | |
2886 | ret = -1; | |
2887 | break; | |
2888 | } | |
2889 | page = list_entry(p, struct page, lru); | |
2890 | ClearPageLRU(page); | |
2891 | list_del(&page->lru); | |
3eefae99 SR |
2892 | tracing_pages_allocated--; |
2893 | tracing_pages_allocated--; | |
a98a3c3f SR |
2894 | __free_page(page); |
2895 | ||
2896 | tracing_reset(data); | |
2897 | ||
2898 | #ifdef CONFIG_TRACER_MAX_TRACE | |
2899 | data = max_tr.data[i]; | |
2900 | p = data->trace_pages.next; | |
2901 | if (p == &data->trace_pages) { | |
2902 | /* should never happen */ | |
2903 | WARN_ON(1); | |
2904 | tracing_disabled = 1; | |
2905 | ret = -1; | |
2906 | break; | |
2907 | } | |
2908 | page = list_entry(p, struct page, lru); | |
2909 | ClearPageLRU(page); | |
2910 | list_del(&page->lru); | |
2911 | __free_page(page); | |
2912 | ||
2913 | tracing_reset(data); | |
2914 | #endif | |
2915 | } | |
2916 | global_trace.entries -= ENTRIES_PER_PAGE; | |
2917 | ||
2918 | return ret; | |
2919 | } | |
2920 | ||
bc0c38d1 SR |
2921 | __init static int tracer_alloc_buffers(void) |
2922 | { | |
4c11d7ae SR |
2923 | struct trace_array_cpu *data; |
2924 | void *array; | |
2925 | struct page *page; | |
2926 | int pages = 0; | |
60a11774 | 2927 | int ret = -ENOMEM; |
bc0c38d1 SR |
2928 | int i; |
2929 | ||
26994ead SR |
2930 | global_trace.ctrl = tracer_enabled; |
2931 | ||
ab46428c SR |
2932 | /* TODO: make the number of buffers hot pluggable with CPUS */ |
2933 | tracing_nr_buffers = num_possible_cpus(); | |
2934 | tracing_buffer_mask = cpu_possible_map; | |
2935 | ||
4c11d7ae | 2936 | /* Allocate the first page for all buffers */ |
ab46428c | 2937 | for_each_tracing_cpu(i) { |
4c11d7ae | 2938 | data = global_trace.data[i] = &per_cpu(global_trace_cpu, i); |
bc0c38d1 SR |
2939 | max_tr.data[i] = &per_cpu(max_data, i); |
2940 | ||
4c11d7ae | 2941 | array = (void *)__get_free_page(GFP_KERNEL); |
bc0c38d1 | 2942 | if (array == NULL) { |
4c11d7ae SR |
2943 | printk(KERN_ERR "tracer: failed to allocate page" |
2944 | "for trace buffer!\n"); | |
bc0c38d1 SR |
2945 | goto free_buffers; |
2946 | } | |
4c11d7ae SR |
2947 | |
2948 | /* set the array to the list */ | |
2949 | INIT_LIST_HEAD(&data->trace_pages); | |
2950 | page = virt_to_page(array); | |
2951 | list_add(&page->lru, &data->trace_pages); | |
2952 | /* use the LRU flag to differentiate the two buffers */ | |
2953 | ClearPageLRU(page); | |
bc0c38d1 | 2954 | |
a98a3c3f SR |
2955 | data->lock = (raw_spinlock_t)__RAW_SPIN_LOCK_UNLOCKED; |
2956 | max_tr.data[i]->lock = (raw_spinlock_t)__RAW_SPIN_LOCK_UNLOCKED; | |
2957 | ||
bc0c38d1 SR |
2958 | /* Only allocate if we are actually using the max trace */ |
2959 | #ifdef CONFIG_TRACER_MAX_TRACE | |
4c11d7ae | 2960 | array = (void *)__get_free_page(GFP_KERNEL); |
bc0c38d1 | 2961 | if (array == NULL) { |
4c11d7ae SR |
2962 | printk(KERN_ERR "tracer: failed to allocate page" |
2963 | "for trace buffer!\n"); | |
bc0c38d1 SR |
2964 | goto free_buffers; |
2965 | } | |
4c11d7ae SR |
2966 | |
2967 | INIT_LIST_HEAD(&max_tr.data[i]->trace_pages); | |
2968 | page = virt_to_page(array); | |
2969 | list_add(&page->lru, &max_tr.data[i]->trace_pages); | |
2970 | SetPageLRU(page); | |
bc0c38d1 SR |
2971 | #endif |
2972 | } | |
2973 | ||
2974 | /* | |
2975 | * Since we allocate by orders of pages, we may be able to | |
2976 | * round up a bit. | |
2977 | */ | |
4c11d7ae | 2978 | global_trace.entries = ENTRIES_PER_PAGE; |
4c11d7ae SR |
2979 | pages++; |
2980 | ||
2981 | while (global_trace.entries < trace_nr_entries) { | |
2982 | if (trace_alloc_page()) | |
2983 | break; | |
2984 | pages++; | |
2985 | } | |
89b2f978 | 2986 | max_tr.entries = global_trace.entries; |
bc0c38d1 | 2987 | |
4c11d7ae SR |
2988 | pr_info("tracer: %d pages allocated for %ld", |
2989 | pages, trace_nr_entries); | |
bc0c38d1 SR |
2990 | pr_info(" entries of %ld bytes\n", (long)TRACE_ENTRY_SIZE); |
2991 | pr_info(" actual entries %ld\n", global_trace.entries); | |
2992 | ||
2993 | tracer_init_debugfs(); | |
2994 | ||
2995 | trace_init_cmdlines(); | |
2996 | ||
2997 | register_tracer(&no_tracer); | |
2998 | current_trace = &no_tracer; | |
2999 | ||
60a11774 SR |
3000 | /* All seems OK, enable tracing */ |
3001 | tracing_disabled = 0; | |
3002 | ||
bc0c38d1 SR |
3003 | return 0; |
3004 | ||
3005 | free_buffers: | |
3006 | for (i-- ; i >= 0; i--) { | |
4c11d7ae | 3007 | struct page *page, *tmp; |
bc0c38d1 SR |
3008 | struct trace_array_cpu *data = global_trace.data[i]; |
3009 | ||
c7aafc54 | 3010 | if (data) { |
4c11d7ae SR |
3011 | list_for_each_entry_safe(page, tmp, |
3012 | &data->trace_pages, lru) { | |
c7aafc54 | 3013 | list_del_init(&page->lru); |
4c11d7ae SR |
3014 | __free_page(page); |
3015 | } | |
bc0c38d1 SR |
3016 | } |
3017 | ||
3018 | #ifdef CONFIG_TRACER_MAX_TRACE | |
3019 | data = max_tr.data[i]; | |
c7aafc54 | 3020 | if (data) { |
4c11d7ae SR |
3021 | list_for_each_entry_safe(page, tmp, |
3022 | &data->trace_pages, lru) { | |
c7aafc54 | 3023 | list_del_init(&page->lru); |
4c11d7ae SR |
3024 | __free_page(page); |
3025 | } | |
bc0c38d1 SR |
3026 | } |
3027 | #endif | |
3028 | } | |
60a11774 | 3029 | return ret; |
bc0c38d1 | 3030 | } |
60a11774 | 3031 | fs_initcall(tracer_alloc_buffers); |