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