rcu: Remove redundant check for rcu_head misalignment
[deliverable/linux.git] / kernel / trace / trace_output.c
CommitLineData
f0868d1e
SR
1/*
2 * trace_output.c
3 *
4 * Copyright (C) 2008 Red Hat Inc, Steven Rostedt <srostedt@redhat.com>
5 *
6 */
7
8#include <linux/module.h>
9#include <linux/mutex.h>
10#include <linux/ftrace.h>
11
12#include "trace_output.h"
13
14/* must be a power of 2 */
15#define EVENT_HASHSIZE 128
16
110bf2b7 17DECLARE_RWSEM(trace_event_mutex);
be74b73a 18
f0868d1e
SR
19static struct hlist_head event_hash[EVENT_HASHSIZE] __read_mostly;
20
21static int next_event_type = __TRACE_LAST_TYPE + 1;
22
a63ce5b3 23int trace_print_seq(struct seq_file *m, struct trace_seq *s)
0706f1c4
SR
24{
25 int len = s->len >= PAGE_SIZE ? PAGE_SIZE - 1 : s->len;
a63ce5b3
SR
26 int ret;
27
28 ret = seq_write(m, s->buffer, len);
0706f1c4 29
a63ce5b3
SR
30 /*
31 * Only reset this buffer if we successfully wrote to the
32 * seq_file buffer.
33 */
34 if (!ret)
35 trace_seq_init(s);
0706f1c4 36
a63ce5b3 37 return ret;
0706f1c4
SR
38}
39
5ef841f6
SR
40enum print_line_t trace_print_bprintk_msg_only(struct trace_iterator *iter)
41{
42 struct trace_seq *s = &iter->seq;
43 struct trace_entry *entry = iter->ent;
44 struct bprint_entry *field;
45 int ret;
46
47 trace_assign_type(field, entry);
48
49 ret = trace_seq_bprintf(s, field->fmt, field->buf);
50 if (!ret)
51 return TRACE_TYPE_PARTIAL_LINE;
52
53 return TRACE_TYPE_HANDLED;
54}
55
56enum print_line_t trace_print_printk_msg_only(struct trace_iterator *iter)
57{
58 struct trace_seq *s = &iter->seq;
59 struct trace_entry *entry = iter->ent;
60 struct print_entry *field;
61 int ret;
62
63 trace_assign_type(field, entry);
64
65 ret = trace_seq_printf(s, "%s", field->buf);
66 if (!ret)
67 return TRACE_TYPE_PARTIAL_LINE;
68
69 return TRACE_TYPE_HANDLED;
70}
71
f0868d1e
SR
72/**
73 * trace_seq_printf - sequence printing of trace information
74 * @s: trace sequence descriptor
75 * @fmt: printf format string
76 *
3e69533b
JO
77 * It returns 0 if the trace oversizes the buffer's free
78 * space, 1 otherwise.
79 *
f0868d1e
SR
80 * The tracer may use either sequence operations or its own
81 * copy to user routines. To simplify formating of a trace
82 * trace_seq_printf is used to store strings into a special
83 * buffer (@s). Then the output may be either used by
84 * the sequencer or pulled into another buffer.
85 */
86int
87trace_seq_printf(struct trace_seq *s, const char *fmt, ...)
88{
89 int len = (PAGE_SIZE - 1) - s->len;
90 va_list ap;
91 int ret;
92
d184b31c 93 if (s->full || !len)
f0868d1e
SR
94 return 0;
95
96 va_start(ap, fmt);
97 ret = vsnprintf(s->buffer + s->len, len, fmt, ap);
98 va_end(ap);
99
100 /* If we can't write it all, don't bother writing anything */
d184b31c
JB
101 if (ret >= len) {
102 s->full = 1;
f0868d1e 103 return 0;
d184b31c 104 }
f0868d1e
SR
105
106 s->len += ret;
107
3e69533b 108 return 1;
f0868d1e 109}
17c873ec 110EXPORT_SYMBOL_GPL(trace_seq_printf);
f0868d1e 111
725c624a
SR
112/**
113 * trace_seq_vprintf - sequence printing of trace information
114 * @s: trace sequence descriptor
115 * @fmt: printf format string
116 *
117 * The tracer may use either sequence operations or its own
118 * copy to user routines. To simplify formating of a trace
119 * trace_seq_printf is used to store strings into a special
120 * buffer (@s). Then the output may be either used by
121 * the sequencer or pulled into another buffer.
122 */
123int
124trace_seq_vprintf(struct trace_seq *s, const char *fmt, va_list args)
125{
126 int len = (PAGE_SIZE - 1) - s->len;
127 int ret;
128
d184b31c 129 if (s->full || !len)
725c624a
SR
130 return 0;
131
132 ret = vsnprintf(s->buffer + s->len, len, fmt, args);
133
134 /* If we can't write it all, don't bother writing anything */
d184b31c
JB
135 if (ret >= len) {
136 s->full = 1;
725c624a 137 return 0;
d184b31c 138 }
725c624a
SR
139
140 s->len += ret;
141
142 return len;
143}
144EXPORT_SYMBOL_GPL(trace_seq_vprintf);
145
769b0441 146int trace_seq_bprintf(struct trace_seq *s, const char *fmt, const u32 *binary)
1427cdf0
LJ
147{
148 int len = (PAGE_SIZE - 1) - s->len;
149 int ret;
150
d184b31c 151 if (s->full || !len)
1427cdf0
LJ
152 return 0;
153
154 ret = bstr_printf(s->buffer + s->len, len, fmt, binary);
155
156 /* If we can't write it all, don't bother writing anything */
d184b31c
JB
157 if (ret >= len) {
158 s->full = 1;
1427cdf0 159 return 0;
d184b31c 160 }
1427cdf0
LJ
161
162 s->len += ret;
163
164 return len;
165}
166
f0868d1e
SR
167/**
168 * trace_seq_puts - trace sequence printing of simple string
169 * @s: trace sequence descriptor
170 * @str: simple string to record
171 *
172 * The tracer may use either the sequence operations or its own
173 * copy to user routines. This function records a simple string
174 * into a special buffer (@s) for later retrieval by a sequencer
175 * or other mechanism.
176 */
177int trace_seq_puts(struct trace_seq *s, const char *str)
178{
179 int len = strlen(str);
180
d184b31c 181 if (s->full)
f0868d1e
SR
182 return 0;
183
d184b31c
JB
184 if (len > ((PAGE_SIZE - 1) - s->len)) {
185 s->full = 1;
186 return 0;
187 }
188
f0868d1e
SR
189 memcpy(s->buffer + s->len, str, len);
190 s->len += len;
191
192 return len;
193}
194
195int trace_seq_putc(struct trace_seq *s, unsigned char c)
196{
d184b31c 197 if (s->full)
f0868d1e
SR
198 return 0;
199
d184b31c
JB
200 if (s->len >= (PAGE_SIZE - 1)) {
201 s->full = 1;
202 return 0;
203 }
204
f0868d1e
SR
205 s->buffer[s->len++] = c;
206
207 return 1;
208}
bf816235 209EXPORT_SYMBOL(trace_seq_putc);
f0868d1e 210
b14b70a6 211int trace_seq_putmem(struct trace_seq *s, const void *mem, size_t len)
f0868d1e 212{
d184b31c 213 if (s->full)
f0868d1e
SR
214 return 0;
215
d184b31c
JB
216 if (len > ((PAGE_SIZE - 1) - s->len)) {
217 s->full = 1;
218 return 0;
219 }
220
f0868d1e
SR
221 memcpy(s->buffer + s->len, mem, len);
222 s->len += len;
223
224 return len;
225}
226
b14b70a6 227int trace_seq_putmem_hex(struct trace_seq *s, const void *mem, size_t len)
f0868d1e
SR
228{
229 unsigned char hex[HEX_CHARS];
b14b70a6 230 const unsigned char *data = mem;
f0868d1e
SR
231 int i, j;
232
d184b31c
JB
233 if (s->full)
234 return 0;
235
f0868d1e
SR
236#ifdef __BIG_ENDIAN
237 for (i = 0, j = 0; i < len; i++) {
238#else
239 for (i = len-1, j = 0; i >= 0; i--) {
240#endif
241 hex[j++] = hex_asc_hi(data[i]);
242 hex[j++] = hex_asc_lo(data[i]);
243 }
244 hex[j++] = ' ';
245
246 return trace_seq_putmem(s, hex, j);
247}
248
bdd6df6a
EGM
249void *trace_seq_reserve(struct trace_seq *s, size_t len)
250{
251 void *ret;
252
d184b31c 253 if (s->full)
668eb65f 254 return NULL;
d184b31c
JB
255
256 if (len > ((PAGE_SIZE - 1) - s->len)) {
257 s->full = 1;
bdd6df6a 258 return NULL;
d184b31c 259 }
bdd6df6a
EGM
260
261 ret = s->buffer + s->len;
262 s->len += len;
263
264 return ret;
265}
266
f0868d1e
SR
267int trace_seq_path(struct trace_seq *s, struct path *path)
268{
269 unsigned char *p;
270
d184b31c 271 if (s->full)
f0868d1e 272 return 0;
d184b31c
JB
273
274 if (s->len >= (PAGE_SIZE - 1)) {
275 s->full = 1;
276 return 0;
277 }
278
f0868d1e
SR
279 p = d_path(path, s->buffer + s->len, PAGE_SIZE - s->len);
280 if (!IS_ERR(p)) {
281 p = mangle_path(s->buffer + s->len, p, "\n");
282 if (p) {
283 s->len = p - s->buffer;
284 return 1;
285 }
286 } else {
287 s->buffer[s->len++] = '?';
288 return 1;
289 }
290
d184b31c 291 s->full = 1;
f0868d1e
SR
292 return 0;
293}
294
be74b73a
SR
295const char *
296ftrace_print_flags_seq(struct trace_seq *p, const char *delim,
297 unsigned long flags,
298 const struct trace_print_flags *flag_array)
299{
300 unsigned long mask;
301 const char *str;
56d8bd3f 302 const char *ret = p->buffer + p->len;
be74b73a
SR
303 int i;
304
be74b73a
SR
305 for (i = 0; flag_array[i].name && flags; i++) {
306
307 mask = flag_array[i].mask;
308 if ((flags & mask) != mask)
309 continue;
310
311 str = flag_array[i].name;
312 flags &= ~mask;
313 if (p->len && delim)
314 trace_seq_puts(p, delim);
315 trace_seq_puts(p, str);
316 }
317
318 /* check for left over flags */
319 if (flags) {
320 if (p->len && delim)
321 trace_seq_puts(p, delim);
322 trace_seq_printf(p, "0x%lx", flags);
323 }
324
325 trace_seq_putc(p, 0);
326
56d8bd3f 327 return ret;
be74b73a 328}
ec081ddc 329EXPORT_SYMBOL(ftrace_print_flags_seq);
be74b73a 330
0f4fc29d
SR
331const char *
332ftrace_print_symbols_seq(struct trace_seq *p, unsigned long val,
333 const struct trace_print_flags *symbol_array)
334{
335 int i;
56d8bd3f 336 const char *ret = p->buffer + p->len;
0f4fc29d
SR
337
338 for (i = 0; symbol_array[i].name; i++) {
339
340 if (val != symbol_array[i].mask)
341 continue;
342
343 trace_seq_puts(p, symbol_array[i].name);
344 break;
345 }
346
347 if (!p->len)
348 trace_seq_printf(p, "0x%lx", val);
349
350 trace_seq_putc(p, 0);
351
56d8bd3f 352 return ret;
0f4fc29d 353}
ec081ddc 354EXPORT_SYMBOL(ftrace_print_symbols_seq);
0f4fc29d 355
2fc1b6f0 356#if BITS_PER_LONG == 32
357const char *
358ftrace_print_symbols_seq_u64(struct trace_seq *p, unsigned long long val,
359 const struct trace_print_flags_u64 *symbol_array)
360{
361 int i;
362 const char *ret = p->buffer + p->len;
363
364 for (i = 0; symbol_array[i].name; i++) {
365
366 if (val != symbol_array[i].mask)
367 continue;
368
369 trace_seq_puts(p, symbol_array[i].name);
370 break;
371 }
372
373 if (!p->len)
374 trace_seq_printf(p, "0x%llx", val);
375
376 trace_seq_putc(p, 0);
377
378 return ret;
379}
380EXPORT_SYMBOL(ftrace_print_symbols_seq_u64);
381#endif
382
5a2e3995
KT
383const char *
384ftrace_print_hex_seq(struct trace_seq *p, const unsigned char *buf, int buf_len)
385{
386 int i;
387 const char *ret = p->buffer + p->len;
388
389 for (i = 0; i < buf_len; i++)
390 trace_seq_printf(p, "%s%2.2x", i == 0 ? "" : " ", buf[i]);
391
392 trace_seq_putc(p, 0);
393
394 return ret;
395}
396EXPORT_SYMBOL(ftrace_print_hex_seq);
397
f0868d1e
SR
398#ifdef CONFIG_KRETPROBES
399static inline const char *kretprobed(const char *name)
400{
401 static const char tramp_name[] = "kretprobe_trampoline";
402 int size = sizeof(tramp_name);
403
404 if (strncmp(tramp_name, name, size) == 0)
405 return "[unknown/kretprobe'd]";
406 return name;
407}
408#else
409static inline const char *kretprobed(const char *name)
410{
411 return name;
412}
413#endif /* CONFIG_KRETPROBES */
414
415static int
416seq_print_sym_short(struct trace_seq *s, const char *fmt, unsigned long address)
417{
418#ifdef CONFIG_KALLSYMS
419 char str[KSYM_SYMBOL_LEN];
420 const char *name;
421
422 kallsyms_lookup(address, NULL, NULL, NULL, str);
423
424 name = kretprobed(str);
425
426 return trace_seq_printf(s, fmt, name);
427#endif
428 return 1;
429}
430
431static int
432seq_print_sym_offset(struct trace_seq *s, const char *fmt,
433 unsigned long address)
434{
435#ifdef CONFIG_KALLSYMS
436 char str[KSYM_SYMBOL_LEN];
437 const char *name;
438
439 sprint_symbol(str, address);
440 name = kretprobed(str);
441
442 return trace_seq_printf(s, fmt, name);
443#endif
444 return 1;
445}
446
447#ifndef CONFIG_64BIT
448# define IP_FMT "%08lx"
449#else
450# define IP_FMT "%016lx"
451#endif
452
453int seq_print_user_ip(struct trace_seq *s, struct mm_struct *mm,
454 unsigned long ip, unsigned long sym_flags)
455{
456 struct file *file = NULL;
457 unsigned long vmstart = 0;
458 int ret = 1;
459
d184b31c
JB
460 if (s->full)
461 return 0;
462
f0868d1e
SR
463 if (mm) {
464 const struct vm_area_struct *vma;
465
466 down_read(&mm->mmap_sem);
467 vma = find_vma(mm, ip);
468 if (vma) {
469 file = vma->vm_file;
470 vmstart = vma->vm_start;
471 }
472 if (file) {
473 ret = trace_seq_path(s, &file->f_path);
474 if (ret)
475 ret = trace_seq_printf(s, "[+0x%lx]",
476 ip - vmstart);
477 }
478 up_read(&mm->mmap_sem);
479 }
480 if (ret && ((sym_flags & TRACE_ITER_SYM_ADDR) || !file))
481 ret = trace_seq_printf(s, " <" IP_FMT ">", ip);
482 return ret;
483}
484
485int
486seq_print_userip_objs(const struct userstack_entry *entry, struct trace_seq *s,
487 unsigned long sym_flags)
488{
489 struct mm_struct *mm = NULL;
490 int ret = 1;
491 unsigned int i;
492
493 if (trace_flags & TRACE_ITER_SYM_USEROBJ) {
494 struct task_struct *task;
495 /*
496 * we do the lookup on the thread group leader,
497 * since individual threads might have already quit!
498 */
499 rcu_read_lock();
48659d31 500 task = find_task_by_vpid(entry->tgid);
f0868d1e
SR
501 if (task)
502 mm = get_task_mm(task);
503 rcu_read_unlock();
504 }
505
506 for (i = 0; i < FTRACE_STACK_ENTRIES; i++) {
507 unsigned long ip = entry->caller[i];
508
509 if (ip == ULONG_MAX || !ret)
510 break;
048dc50c 511 if (ret)
512 ret = trace_seq_puts(s, " => ");
f0868d1e
SR
513 if (!ip) {
514 if (ret)
515 ret = trace_seq_puts(s, "??");
048dc50c 516 if (ret)
517 ret = trace_seq_puts(s, "\n");
f0868d1e
SR
518 continue;
519 }
520 if (!ret)
521 break;
522 if (ret)
523 ret = seq_print_user_ip(s, mm, ip, sym_flags);
048dc50c 524 ret = trace_seq_puts(s, "\n");
f0868d1e
SR
525 }
526
527 if (mm)
528 mmput(mm);
529 return ret;
530}
531
532int
533seq_print_ip_sym(struct trace_seq *s, unsigned long ip, unsigned long sym_flags)
534{
535 int ret;
536
537 if (!ip)
538 return trace_seq_printf(s, "0");
539
540 if (sym_flags & TRACE_ITER_SYM_OFFSET)
541 ret = seq_print_sym_offset(s, "%s", ip);
542 else
543 ret = seq_print_sym_short(s, "%s", ip);
544
545 if (!ret)
546 return 0;
547
548 if (sym_flags & TRACE_ITER_SYM_ADDR)
549 ret = trace_seq_printf(s, " <" IP_FMT ">", ip);
550 return ret;
551}
552
f81c972d
SR
553/**
554 * trace_print_lat_fmt - print the irq, preempt and lockdep fields
555 * @s: trace seq struct to write to
556 * @entry: The trace entry field from the ring buffer
557 *
558 * Prints the generic fields of irqs off, in hard or softirq, preempt
e6e1e259 559 * count.
f81c972d
SR
560 */
561int trace_print_lat_fmt(struct trace_seq *s, struct trace_entry *entry)
c4a8e8be 562{
10da37a6
DS
563 char hardsoft_irq;
564 char need_resched;
565 char irqs_off;
566 int hardirq;
567 int softirq;
637e7e86 568 int ret;
c4a8e8be 569
c4a8e8be
FW
570 hardirq = entry->flags & TRACE_FLAG_HARDIRQ;
571 softirq = entry->flags & TRACE_FLAG_SOFTIRQ;
d9793bd8 572
10da37a6
DS
573 irqs_off =
574 (entry->flags & TRACE_FLAG_IRQS_OFF) ? 'd' :
575 (entry->flags & TRACE_FLAG_IRQS_NOSUPPORT) ? 'X' :
576 '.';
577 need_resched =
578 (entry->flags & TRACE_FLAG_NEED_RESCHED) ? 'N' : '.';
579 hardsoft_irq =
580 (hardirq && softirq) ? 'H' :
581 hardirq ? 'h' :
582 softirq ? 's' :
583 '.';
584
f81c972d 585 if (!trace_seq_printf(s, "%c%c%c",
10da37a6 586 irqs_off, need_resched, hardsoft_irq))
d9793bd8 587 return 0;
c4a8e8be 588
829b876d
SR
589 if (entry->preempt_count)
590 ret = trace_seq_printf(s, "%x", entry->preempt_count);
637e7e86 591 else
829b876d
SR
592 ret = trace_seq_putc(s, '.');
593
e6e1e259 594 return ret;
c4a8e8be
FW
595}
596
f81c972d
SR
597static int
598lat_print_generic(struct trace_seq *s, struct trace_entry *entry, int cpu)
599{
600 char comm[TASK_COMM_LEN];
601
602 trace_find_cmdline(entry->pid, comm);
603
604 if (!trace_seq_printf(s, "%8.8s-%-5d %3d",
605 comm, entry->pid, cpu))
606 return 0;
607
608 return trace_print_lat_fmt(s, entry);
609}
610
c4a8e8be
FW
611static unsigned long preempt_mark_thresh = 100;
612
d9793bd8 613static int
c4a8e8be
FW
614lat_print_timestamp(struct trace_seq *s, u64 abs_usecs,
615 unsigned long rel_usecs)
616{
d9793bd8
ACM
617 return trace_seq_printf(s, " %4lldus%c: ", abs_usecs,
618 rel_usecs > preempt_mark_thresh ? '!' :
619 rel_usecs > 1 ? '+' : ' ');
c4a8e8be
FW
620}
621
622int trace_print_context(struct trace_iterator *iter)
623{
624 struct trace_seq *s = &iter->seq;
625 struct trace_entry *entry = iter->ent;
c4a8e8be
FW
626 unsigned long long t = ns2usecs(iter->ts);
627 unsigned long usec_rem = do_div(t, USEC_PER_SEC);
628 unsigned long secs = (unsigned long)t;
4ca53085 629 char comm[TASK_COMM_LEN];
77271ce4 630 int ret;
4ca53085
SR
631
632 trace_find_cmdline(entry->pid, comm);
c4a8e8be 633
77271ce4
SR
634 ret = trace_seq_printf(s, "%16s-%-5d [%03d] ",
635 comm, entry->pid, iter->cpu);
636 if (!ret)
637 return 0;
638
639 if (trace_flags & TRACE_ITER_IRQ_INFO) {
640 ret = trace_print_lat_fmt(s, entry);
641 if (!ret)
642 return 0;
643 }
644
645 return trace_seq_printf(s, " %5lu.%06lu: ",
646 secs, usec_rem);
c4a8e8be
FW
647}
648
649int trace_print_lat_context(struct trace_iterator *iter)
650{
651 u64 next_ts;
d9793bd8 652 int ret;
c4a8e8be
FW
653 struct trace_seq *s = &iter->seq;
654 struct trace_entry *entry = iter->ent,
655 *next_entry = trace_find_next_entry(iter, NULL,
656 &next_ts);
657 unsigned long verbose = (trace_flags & TRACE_ITER_VERBOSE);
658 unsigned long abs_usecs = ns2usecs(iter->ts - iter->tr->time_start);
659 unsigned long rel_usecs;
660
661 if (!next_entry)
662 next_ts = iter->ts;
663 rel_usecs = ns2usecs(next_ts - iter->ts);
664
665 if (verbose) {
4ca53085
SR
666 char comm[TASK_COMM_LEN];
667
668 trace_find_cmdline(entry->pid, comm);
669
cf8e3474 670 ret = trace_seq_printf(s, "%16s %5d %3d %d %08x %08lx [%08llx]"
d9793bd8 671 " %ld.%03ldms (+%ld.%03ldms): ", comm,
1830b52d 672 entry->pid, iter->cpu, entry->flags,
d9793bd8
ACM
673 entry->preempt_count, iter->idx,
674 ns2usecs(iter->ts),
675 abs_usecs / USEC_PER_MSEC,
676 abs_usecs % USEC_PER_MSEC,
677 rel_usecs / USEC_PER_MSEC,
678 rel_usecs % USEC_PER_MSEC);
c4a8e8be 679 } else {
1830b52d 680 ret = lat_print_generic(s, entry, iter->cpu);
d9793bd8
ACM
681 if (ret)
682 ret = lat_print_timestamp(s, abs_usecs, rel_usecs);
c4a8e8be
FW
683 }
684
d9793bd8 685 return ret;
c4a8e8be
FW
686}
687
f633cef0
SR
688static const char state_to_char[] = TASK_STATE_TO_CHAR_STR;
689
690static int task_state_char(unsigned long state)
691{
692 int bit = state ? __ffs(state) + 1 : 0;
693
694 return bit < sizeof(state_to_char) - 1 ? state_to_char[bit] : '?';
695}
696
f0868d1e
SR
697/**
698 * ftrace_find_event - find a registered event
699 * @type: the type of event to look for
700 *
701 * Returns an event of type @type otherwise NULL
4f535968 702 * Called with trace_event_read_lock() held.
f0868d1e
SR
703 */
704struct trace_event *ftrace_find_event(int type)
705{
706 struct trace_event *event;
707 struct hlist_node *n;
708 unsigned key;
709
710 key = type & (EVENT_HASHSIZE - 1);
711
4f535968 712 hlist_for_each_entry(event, n, &event_hash[key], node) {
f0868d1e
SR
713 if (event->type == type)
714 return event;
715 }
716
717 return NULL;
718}
719
060fa5c8
SR
720static LIST_HEAD(ftrace_event_list);
721
722static int trace_search_list(struct list_head **list)
723{
724 struct trace_event *e;
725 int last = __TRACE_LAST_TYPE;
726
727 if (list_empty(&ftrace_event_list)) {
728 *list = &ftrace_event_list;
729 return last + 1;
730 }
731
732 /*
733 * We used up all possible max events,
734 * lets see if somebody freed one.
735 */
736 list_for_each_entry(e, &ftrace_event_list, list) {
737 if (e->type != last + 1)
738 break;
739 last++;
740 }
741
742 /* Did we used up all 65 thousand events??? */
743 if ((last + 1) > FTRACE_MAX_EVENT)
744 return 0;
745
746 *list = &e->list;
747 return last + 1;
748}
749
4f535968
LJ
750void trace_event_read_lock(void)
751{
752 down_read(&trace_event_mutex);
753}
754
755void trace_event_read_unlock(void)
756{
757 up_read(&trace_event_mutex);
758}
759
f0868d1e
SR
760/**
761 * register_ftrace_event - register output for an event type
762 * @event: the event type to register
763 *
764 * Event types are stored in a hash and this hash is used to
765 * find a way to print an event. If the @event->type is set
766 * then it will use that type, otherwise it will assign a
767 * type to use.
768 *
769 * If you assign your own type, please make sure it is added
770 * to the trace_type enum in trace.h, to avoid collisions
771 * with the dynamic types.
772 *
773 * Returns the event type number or zero on error.
774 */
775int register_ftrace_event(struct trace_event *event)
776{
777 unsigned key;
778 int ret = 0;
779
4f535968 780 down_write(&trace_event_mutex);
f0868d1e 781
060fa5c8 782 if (WARN_ON(!event))
28bea271 783 goto out;
28bea271 784
a9a57763
SR
785 if (WARN_ON(!event->funcs))
786 goto out;
787
060fa5c8
SR
788 INIT_LIST_HEAD(&event->list);
789
790 if (!event->type) {
48dd0fed 791 struct list_head *list = NULL;
060fa5c8
SR
792
793 if (next_event_type > FTRACE_MAX_EVENT) {
794
795 event->type = trace_search_list(&list);
796 if (!event->type)
797 goto out;
798
799 } else {
800
801 event->type = next_event_type++;
802 list = &ftrace_event_list;
803 }
804
805 if (WARN_ON(ftrace_find_event(event->type)))
806 goto out;
807
808 list_add_tail(&event->list, list);
809
810 } else if (event->type > __TRACE_LAST_TYPE) {
f0868d1e
SR
811 printk(KERN_WARNING "Need to add type to trace.h\n");
812 WARN_ON(1);
f0868d1e 813 goto out;
060fa5c8
SR
814 } else {
815 /* Is this event already used */
816 if (ftrace_find_event(event->type))
817 goto out;
818 }
f0868d1e 819
a9a57763
SR
820 if (event->funcs->trace == NULL)
821 event->funcs->trace = trace_nop_print;
822 if (event->funcs->raw == NULL)
823 event->funcs->raw = trace_nop_print;
824 if (event->funcs->hex == NULL)
825 event->funcs->hex = trace_nop_print;
826 if (event->funcs->binary == NULL)
827 event->funcs->binary = trace_nop_print;
268ccda0 828
f0868d1e
SR
829 key = event->type & (EVENT_HASHSIZE - 1);
830
4f535968 831 hlist_add_head(&event->node, &event_hash[key]);
f0868d1e
SR
832
833 ret = event->type;
834 out:
4f535968 835 up_write(&trace_event_mutex);
f0868d1e
SR
836
837 return ret;
838}
17c873ec 839EXPORT_SYMBOL_GPL(register_ftrace_event);
f0868d1e 840
110bf2b7
SR
841/*
842 * Used by module code with the trace_event_mutex held for write.
843 */
844int __unregister_ftrace_event(struct trace_event *event)
845{
846 hlist_del(&event->node);
847 list_del(&event->list);
848 return 0;
849}
850
f0868d1e
SR
851/**
852 * unregister_ftrace_event - remove a no longer used event
853 * @event: the event to remove
854 */
855int unregister_ftrace_event(struct trace_event *event)
856{
4f535968 857 down_write(&trace_event_mutex);
110bf2b7 858 __unregister_ftrace_event(event);
4f535968 859 up_write(&trace_event_mutex);
f0868d1e
SR
860
861 return 0;
862}
17c873ec 863EXPORT_SYMBOL_GPL(unregister_ftrace_event);
f633cef0
SR
864
865/*
866 * Standard events
867 */
868
a9a57763
SR
869enum print_line_t trace_nop_print(struct trace_iterator *iter, int flags,
870 struct trace_event *event)
f633cef0 871{
ee5e51f5
JO
872 if (!trace_seq_printf(&iter->seq, "type: %d\n", iter->ent->type))
873 return TRACE_TYPE_PARTIAL_LINE;
874
d9793bd8 875 return TRACE_TYPE_HANDLED;
f633cef0
SR
876}
877
878/* TRACE_FN */
a9a57763
SR
879static enum print_line_t trace_fn_trace(struct trace_iterator *iter, int flags,
880 struct trace_event *event)
f633cef0
SR
881{
882 struct ftrace_entry *field;
2c9b238e 883 struct trace_seq *s = &iter->seq;
f633cef0 884
2c9b238e 885 trace_assign_type(field, iter->ent);
f633cef0
SR
886
887 if (!seq_print_ip_sym(s, field->ip, flags))
888 goto partial;
889
890 if ((flags & TRACE_ITER_PRINT_PARENT) && field->parent_ip) {
891 if (!trace_seq_printf(s, " <-"))
892 goto partial;
893 if (!seq_print_ip_sym(s,
894 field->parent_ip,
895 flags))
896 goto partial;
897 }
898 if (!trace_seq_printf(s, "\n"))
899 goto partial;
900
d9793bd8 901 return TRACE_TYPE_HANDLED;
f633cef0
SR
902
903 partial:
904 return TRACE_TYPE_PARTIAL_LINE;
905}
906
a9a57763
SR
907static enum print_line_t trace_fn_raw(struct trace_iterator *iter, int flags,
908 struct trace_event *event)
f633cef0
SR
909{
910 struct ftrace_entry *field;
911
2c9b238e 912 trace_assign_type(field, iter->ent);
f633cef0 913
2c9b238e 914 if (!trace_seq_printf(&iter->seq, "%lx %lx\n",
6c1a99af
LJ
915 field->ip,
916 field->parent_ip))
f633cef0
SR
917 return TRACE_TYPE_PARTIAL_LINE;
918
d9793bd8 919 return TRACE_TYPE_HANDLED;
f633cef0
SR
920}
921
a9a57763
SR
922static enum print_line_t trace_fn_hex(struct trace_iterator *iter, int flags,
923 struct trace_event *event)
f633cef0
SR
924{
925 struct ftrace_entry *field;
2c9b238e 926 struct trace_seq *s = &iter->seq;
f633cef0 927
2c9b238e 928 trace_assign_type(field, iter->ent);
f633cef0
SR
929
930 SEQ_PUT_HEX_FIELD_RET(s, field->ip);
931 SEQ_PUT_HEX_FIELD_RET(s, field->parent_ip);
932
d9793bd8 933 return TRACE_TYPE_HANDLED;
f633cef0
SR
934}
935
a9a57763
SR
936static enum print_line_t trace_fn_bin(struct trace_iterator *iter, int flags,
937 struct trace_event *event)
f633cef0
SR
938{
939 struct ftrace_entry *field;
2c9b238e 940 struct trace_seq *s = &iter->seq;
f633cef0 941
2c9b238e 942 trace_assign_type(field, iter->ent);
f633cef0
SR
943
944 SEQ_PUT_FIELD_RET(s, field->ip);
945 SEQ_PUT_FIELD_RET(s, field->parent_ip);
946
d9793bd8 947 return TRACE_TYPE_HANDLED;
f633cef0
SR
948}
949
a9a57763 950static struct trace_event_functions trace_fn_funcs = {
f633cef0 951 .trace = trace_fn_trace,
f633cef0
SR
952 .raw = trace_fn_raw,
953 .hex = trace_fn_hex,
954 .binary = trace_fn_bin,
955};
956
a9a57763
SR
957static struct trace_event trace_fn_event = {
958 .type = TRACE_FN,
959 .funcs = &trace_fn_funcs,
960};
961
f633cef0 962/* TRACE_CTX an TRACE_WAKE */
ae7462b4
ACM
963static enum print_line_t trace_ctxwake_print(struct trace_iterator *iter,
964 char *delim)
f633cef0
SR
965{
966 struct ctx_switch_entry *field;
4ca53085 967 char comm[TASK_COMM_LEN];
f633cef0
SR
968 int S, T;
969
4ca53085 970
2c9b238e 971 trace_assign_type(field, iter->ent);
f633cef0
SR
972
973 T = task_state_char(field->next_state);
974 S = task_state_char(field->prev_state);
4ca53085 975 trace_find_cmdline(field->next_pid, comm);
2c9b238e
ACM
976 if (!trace_seq_printf(&iter->seq,
977 " %5d:%3d:%c %s [%03d] %5d:%3d:%c %s\n",
6c1a99af
LJ
978 field->prev_pid,
979 field->prev_prio,
980 S, delim,
981 field->next_cpu,
982 field->next_pid,
983 field->next_prio,
984 T, comm))
f633cef0
SR
985 return TRACE_TYPE_PARTIAL_LINE;
986
d9793bd8 987 return TRACE_TYPE_HANDLED;
f633cef0
SR
988}
989
a9a57763
SR
990static enum print_line_t trace_ctx_print(struct trace_iterator *iter, int flags,
991 struct trace_event *event)
f633cef0 992{
2c9b238e 993 return trace_ctxwake_print(iter, "==>");
f633cef0
SR
994}
995
ae7462b4 996static enum print_line_t trace_wake_print(struct trace_iterator *iter,
a9a57763 997 int flags, struct trace_event *event)
f633cef0 998{
2c9b238e 999 return trace_ctxwake_print(iter, " +");
f633cef0
SR
1000}
1001
2c9b238e 1002static int trace_ctxwake_raw(struct trace_iterator *iter, char S)
f633cef0
SR
1003{
1004 struct ctx_switch_entry *field;
1005 int T;
1006
2c9b238e 1007 trace_assign_type(field, iter->ent);
f633cef0
SR
1008
1009 if (!S)
b0f56f1a 1010 S = task_state_char(field->prev_state);
f633cef0 1011 T = task_state_char(field->next_state);
2c9b238e 1012 if (!trace_seq_printf(&iter->seq, "%d %d %c %d %d %d %c\n",
6c1a99af
LJ
1013 field->prev_pid,
1014 field->prev_prio,
1015 S,
1016 field->next_cpu,
1017 field->next_pid,
1018 field->next_prio,
1019 T))
f633cef0
SR
1020 return TRACE_TYPE_PARTIAL_LINE;
1021
d9793bd8 1022 return TRACE_TYPE_HANDLED;
f633cef0
SR
1023}
1024
a9a57763
SR
1025static enum print_line_t trace_ctx_raw(struct trace_iterator *iter, int flags,
1026 struct trace_event *event)
f633cef0 1027{
2c9b238e 1028 return trace_ctxwake_raw(iter, 0);
f633cef0
SR
1029}
1030
a9a57763
SR
1031static enum print_line_t trace_wake_raw(struct trace_iterator *iter, int flags,
1032 struct trace_event *event)
f633cef0 1033{
2c9b238e 1034 return trace_ctxwake_raw(iter, '+');
f633cef0
SR
1035}
1036
1037
2c9b238e 1038static int trace_ctxwake_hex(struct trace_iterator *iter, char S)
f633cef0
SR
1039{
1040 struct ctx_switch_entry *field;
2c9b238e 1041 struct trace_seq *s = &iter->seq;
f633cef0
SR
1042 int T;
1043
2c9b238e 1044 trace_assign_type(field, iter->ent);
f633cef0
SR
1045
1046 if (!S)
b0f56f1a 1047 S = task_state_char(field->prev_state);
f633cef0
SR
1048 T = task_state_char(field->next_state);
1049
1050 SEQ_PUT_HEX_FIELD_RET(s, field->prev_pid);
1051 SEQ_PUT_HEX_FIELD_RET(s, field->prev_prio);
1052 SEQ_PUT_HEX_FIELD_RET(s, S);
1053 SEQ_PUT_HEX_FIELD_RET(s, field->next_cpu);
1054 SEQ_PUT_HEX_FIELD_RET(s, field->next_pid);
1055 SEQ_PUT_HEX_FIELD_RET(s, field->next_prio);
1056 SEQ_PUT_HEX_FIELD_RET(s, T);
1057
d9793bd8 1058 return TRACE_TYPE_HANDLED;
f633cef0
SR
1059}
1060
a9a57763
SR
1061static enum print_line_t trace_ctx_hex(struct trace_iterator *iter, int flags,
1062 struct trace_event *event)
f633cef0 1063{
2c9b238e 1064 return trace_ctxwake_hex(iter, 0);
f633cef0
SR
1065}
1066
a9a57763
SR
1067static enum print_line_t trace_wake_hex(struct trace_iterator *iter, int flags,
1068 struct trace_event *event)
f633cef0 1069{
2c9b238e 1070 return trace_ctxwake_hex(iter, '+');
f633cef0
SR
1071}
1072
ae7462b4 1073static enum print_line_t trace_ctxwake_bin(struct trace_iterator *iter,
a9a57763 1074 int flags, struct trace_event *event)
f633cef0
SR
1075{
1076 struct ctx_switch_entry *field;
2c9b238e 1077 struct trace_seq *s = &iter->seq;
f633cef0 1078
2c9b238e 1079 trace_assign_type(field, iter->ent);
f633cef0
SR
1080
1081 SEQ_PUT_FIELD_RET(s, field->prev_pid);
1082 SEQ_PUT_FIELD_RET(s, field->prev_prio);
1083 SEQ_PUT_FIELD_RET(s, field->prev_state);
1084 SEQ_PUT_FIELD_RET(s, field->next_pid);
1085 SEQ_PUT_FIELD_RET(s, field->next_prio);
1086 SEQ_PUT_FIELD_RET(s, field->next_state);
1087
d9793bd8 1088 return TRACE_TYPE_HANDLED;
f633cef0
SR
1089}
1090
a9a57763 1091static struct trace_event_functions trace_ctx_funcs = {
f633cef0 1092 .trace = trace_ctx_print,
f633cef0
SR
1093 .raw = trace_ctx_raw,
1094 .hex = trace_ctx_hex,
1095 .binary = trace_ctxwake_bin,
1096};
1097
a9a57763
SR
1098static struct trace_event trace_ctx_event = {
1099 .type = TRACE_CTX,
1100 .funcs = &trace_ctx_funcs,
1101};
1102
1103static struct trace_event_functions trace_wake_funcs = {
f633cef0 1104 .trace = trace_wake_print,
f633cef0
SR
1105 .raw = trace_wake_raw,
1106 .hex = trace_wake_hex,
1107 .binary = trace_ctxwake_bin,
1108};
1109
a9a57763
SR
1110static struct trace_event trace_wake_event = {
1111 .type = TRACE_WAKE,
1112 .funcs = &trace_wake_funcs,
1113};
1114
f633cef0
SR
1115/* TRACE_STACK */
1116
ae7462b4 1117static enum print_line_t trace_stack_print(struct trace_iterator *iter,
a9a57763 1118 int flags, struct trace_event *event)
f633cef0
SR
1119{
1120 struct stack_entry *field;
2c9b238e 1121 struct trace_seq *s = &iter->seq;
4a9bd3f1
SR
1122 unsigned long *p;
1123 unsigned long *end;
f633cef0 1124
2c9b238e 1125 trace_assign_type(field, iter->ent);
4a9bd3f1 1126 end = (unsigned long *)((long)iter->ent + iter->ent_size);
f633cef0 1127
563af16c 1128 if (!trace_seq_puts(s, "<stack trace>\n"))
f11b3f4e 1129 goto partial;
4a9bd3f1
SR
1130
1131 for (p = field->caller; p && *p != ULONG_MAX && p < end; p++) {
f11b3f4e 1132 if (!trace_seq_puts(s, " => "))
1133 goto partial;
f633cef0 1134
4a9bd3f1 1135 if (!seq_print_ip_sym(s, *p, flags))
f11b3f4e 1136 goto partial;
6c1a99af 1137 if (!trace_seq_puts(s, "\n"))
f633cef0
SR
1138 goto partial;
1139 }
1140
d9793bd8 1141 return TRACE_TYPE_HANDLED;
f633cef0
SR
1142
1143 partial:
1144 return TRACE_TYPE_PARTIAL_LINE;
1145}
1146
a9a57763 1147static struct trace_event_functions trace_stack_funcs = {
f633cef0 1148 .trace = trace_stack_print,
f633cef0
SR
1149};
1150
a9a57763
SR
1151static struct trace_event trace_stack_event = {
1152 .type = TRACE_STACK,
1153 .funcs = &trace_stack_funcs,
1154};
1155
f633cef0 1156/* TRACE_USER_STACK */
ae7462b4 1157static enum print_line_t trace_user_stack_print(struct trace_iterator *iter,
a9a57763 1158 int flags, struct trace_event *event)
f633cef0
SR
1159{
1160 struct userstack_entry *field;
2c9b238e 1161 struct trace_seq *s = &iter->seq;
f633cef0 1162
2c9b238e 1163 trace_assign_type(field, iter->ent);
f633cef0 1164
563af16c 1165 if (!trace_seq_puts(s, "<user stack trace>\n"))
f633cef0
SR
1166 goto partial;
1167
048dc50c 1168 if (!seq_print_userip_objs(field, s, flags))
f633cef0
SR
1169 goto partial;
1170
d9793bd8 1171 return TRACE_TYPE_HANDLED;
f633cef0
SR
1172
1173 partial:
1174 return TRACE_TYPE_PARTIAL_LINE;
1175}
1176
a9a57763 1177static struct trace_event_functions trace_user_stack_funcs = {
f633cef0 1178 .trace = trace_user_stack_print,
f633cef0
SR
1179};
1180
a9a57763
SR
1181static struct trace_event trace_user_stack_event = {
1182 .type = TRACE_USER_STACK,
1183 .funcs = &trace_user_stack_funcs,
1184};
1185
48ead020 1186/* TRACE_BPRINT */
1427cdf0 1187static enum print_line_t
a9a57763
SR
1188trace_bprint_print(struct trace_iterator *iter, int flags,
1189 struct trace_event *event)
1427cdf0
LJ
1190{
1191 struct trace_entry *entry = iter->ent;
1192 struct trace_seq *s = &iter->seq;
48ead020 1193 struct bprint_entry *field;
1427cdf0
LJ
1194
1195 trace_assign_type(field, entry);
1196
1197 if (!seq_print_ip_sym(s, field->ip, flags))
1198 goto partial;
1199
1200 if (!trace_seq_puts(s, ": "))
1201 goto partial;
1202
1203 if (!trace_seq_bprintf(s, field->fmt, field->buf))
1204 goto partial;
1205
1206 return TRACE_TYPE_HANDLED;
1207
1208 partial:
1209 return TRACE_TYPE_PARTIAL_LINE;
1210}
1211
769b0441 1212
48ead020 1213static enum print_line_t
a9a57763
SR
1214trace_bprint_raw(struct trace_iterator *iter, int flags,
1215 struct trace_event *event)
1427cdf0 1216{
48ead020 1217 struct bprint_entry *field;
1427cdf0 1218 struct trace_seq *s = &iter->seq;
1427cdf0 1219
769b0441 1220 trace_assign_type(field, iter->ent);
1427cdf0
LJ
1221
1222 if (!trace_seq_printf(s, ": %lx : ", field->ip))
1223 goto partial;
1224
1225 if (!trace_seq_bprintf(s, field->fmt, field->buf))
1226 goto partial;
1227
1228 return TRACE_TYPE_HANDLED;
1229
1230 partial:
1231 return TRACE_TYPE_PARTIAL_LINE;
1232}
1233
a9a57763
SR
1234static struct trace_event_functions trace_bprint_funcs = {
1235 .trace = trace_bprint_print,
1236 .raw = trace_bprint_raw,
1237};
769b0441 1238
48ead020
FW
1239static struct trace_event trace_bprint_event = {
1240 .type = TRACE_BPRINT,
a9a57763 1241 .funcs = &trace_bprint_funcs,
48ead020
FW
1242};
1243
1244/* TRACE_PRINT */
1245static enum print_line_t trace_print_print(struct trace_iterator *iter,
a9a57763 1246 int flags, struct trace_event *event)
48ead020
FW
1247{
1248 struct print_entry *field;
1249 struct trace_seq *s = &iter->seq;
1250
1251 trace_assign_type(field, iter->ent);
1252
1253 if (!seq_print_ip_sym(s, field->ip, flags))
1254 goto partial;
1255
1256 if (!trace_seq_printf(s, ": %s", field->buf))
1257 goto partial;
1258
1259 return TRACE_TYPE_HANDLED;
1260
1261 partial:
1262 return TRACE_TYPE_PARTIAL_LINE;
1263}
1264
a9a57763
SR
1265static enum print_line_t trace_print_raw(struct trace_iterator *iter, int flags,
1266 struct trace_event *event)
48ead020
FW
1267{
1268 struct print_entry *field;
1269
1270 trace_assign_type(field, iter->ent);
1271
1272 if (!trace_seq_printf(&iter->seq, "# %lx %s", field->ip, field->buf))
1273 goto partial;
1274
1275 return TRACE_TYPE_HANDLED;
1276
1277 partial:
1278 return TRACE_TYPE_PARTIAL_LINE;
1279}
1280
a9a57763 1281static struct trace_event_functions trace_print_funcs = {
769b0441
FW
1282 .trace = trace_print_print,
1283 .raw = trace_print_raw,
1427cdf0
LJ
1284};
1285
a9a57763
SR
1286static struct trace_event trace_print_event = {
1287 .type = TRACE_PRINT,
1288 .funcs = &trace_print_funcs,
1289};
1290
48ead020 1291
f633cef0
SR
1292static struct trace_event *events[] __initdata = {
1293 &trace_fn_event,
1294 &trace_ctx_event,
1295 &trace_wake_event,
f633cef0
SR
1296 &trace_stack_event,
1297 &trace_user_stack_event,
48ead020 1298 &trace_bprint_event,
f633cef0
SR
1299 &trace_print_event,
1300 NULL
1301};
1302
1303__init static int init_events(void)
1304{
1305 struct trace_event *event;
1306 int i, ret;
1307
1308 for (i = 0; events[i]; i++) {
1309 event = events[i];
1310
1311 ret = register_ftrace_event(event);
1312 if (!ret) {
1313 printk(KERN_WARNING "event %d failed to register\n",
1314 event->type);
1315 WARN_ON_ONCE(1);
1316 }
1317 }
1318
1319 return 0;
1320}
1321device_initcall(init_events);
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