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
17 DECLARE_RWSEM(trace_event_mutex);
18
19 static struct hlist_head event_hash[EVENT_HASHSIZE] __read_mostly;
20
21 static int next_event_type = __TRACE_LAST_TYPE + 1;
22
trace_print_seq(struct seq_file * m,struct trace_seq * s)23 int trace_print_seq(struct seq_file *m, struct trace_seq *s)
24 {
25 int len = s->len >= PAGE_SIZE ? PAGE_SIZE - 1 : s->len;
26 int ret;
27
28 ret = seq_write(m, s->buffer, len);
29
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);
36
37 return ret;
38 }
39
trace_print_bprintk_msg_only(struct trace_iterator * iter)40 enum 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
trace_print_printk_msg_only(struct trace_iterator * iter)56 enum 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
72 /**
73 * trace_seq_printf - sequence printing of trace information
74 * @s: trace sequence descriptor
75 * @fmt: printf format string
76 *
77 * It returns 0 if the trace oversizes the buffer's free
78 * space, 1 otherwise.
79 *
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 */
86 int
trace_seq_printf(struct trace_seq * s,const char * fmt,...)87 trace_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
93 if (s->full || !len)
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 */
101 if (ret >= len) {
102 s->full = 1;
103 return 0;
104 }
105
106 s->len += ret;
107
108 return 1;
109 }
110 EXPORT_SYMBOL_GPL(trace_seq_printf);
111
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 */
123 int
trace_seq_vprintf(struct trace_seq * s,const char * fmt,va_list args)124 trace_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
129 if (s->full || !len)
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 */
135 if (ret >= len) {
136 s->full = 1;
137 return 0;
138 }
139
140 s->len += ret;
141
142 return len;
143 }
144 EXPORT_SYMBOL_GPL(trace_seq_vprintf);
145
trace_seq_bprintf(struct trace_seq * s,const char * fmt,const u32 * binary)146 int trace_seq_bprintf(struct trace_seq *s, const char *fmt, const u32 *binary)
147 {
148 int len = (PAGE_SIZE - 1) - s->len;
149 int ret;
150
151 if (s->full || !len)
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 */
157 if (ret >= len) {
158 s->full = 1;
159 return 0;
160 }
161
162 s->len += ret;
163
164 return len;
165 }
166
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 */
trace_seq_puts(struct trace_seq * s,const char * str)177 int trace_seq_puts(struct trace_seq *s, const char *str)
178 {
179 int len = strlen(str);
180
181 if (s->full)
182 return 0;
183
184 if (len > ((PAGE_SIZE - 1) - s->len)) {
185 s->full = 1;
186 return 0;
187 }
188
189 memcpy(s->buffer + s->len, str, len);
190 s->len += len;
191
192 return len;
193 }
194
trace_seq_putc(struct trace_seq * s,unsigned char c)195 int trace_seq_putc(struct trace_seq *s, unsigned char c)
196 {
197 if (s->full)
198 return 0;
199
200 if (s->len >= (PAGE_SIZE - 1)) {
201 s->full = 1;
202 return 0;
203 }
204
205 s->buffer[s->len++] = c;
206
207 return 1;
208 }
209 EXPORT_SYMBOL(trace_seq_putc);
210
trace_seq_putmem(struct trace_seq * s,const void * mem,size_t len)211 int trace_seq_putmem(struct trace_seq *s, const void *mem, size_t len)
212 {
213 if (s->full)
214 return 0;
215
216 if (len > ((PAGE_SIZE - 1) - s->len)) {
217 s->full = 1;
218 return 0;
219 }
220
221 memcpy(s->buffer + s->len, mem, len);
222 s->len += len;
223
224 return len;
225 }
226
trace_seq_putmem_hex(struct trace_seq * s,const void * mem,size_t len)227 int trace_seq_putmem_hex(struct trace_seq *s, const void *mem, size_t len)
228 {
229 unsigned char hex[HEX_CHARS];
230 const unsigned char *data = mem;
231 int i, j;
232
233 if (s->full)
234 return 0;
235
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
249 void *trace_seq_reserve(struct trace_seq *s, size_t len)
250 {
251 void *ret;
252
253 if (s->full)
254 return NULL;
255
256 if (len > ((PAGE_SIZE - 1) - s->len)) {
257 s->full = 1;
258 return NULL;
259 }
260
261 ret = s->buffer + s->len;
262 s->len += len;
263
264 return ret;
265 }
266
267 int trace_seq_path(struct trace_seq *s, const struct path *path)
268 {
269 unsigned char *p;
270
271 if (s->full)
272 return 0;
273
274 if (s->len >= (PAGE_SIZE - 1)) {
275 s->full = 1;
276 return 0;
277 }
278
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
291 s->full = 1;
292 return 0;
293 }
294
295 const char *
296 ftrace_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;
302 const char *ret = p->buffer + p->len;
303 int i, first = 1;
304
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 (!first && delim)
314 trace_seq_puts(p, delim);
315 else
316 first = 0;
317 trace_seq_puts(p, str);
318 }
319
320 /* check for left over flags */
321 if (flags) {
322 if (!first && delim)
323 trace_seq_puts(p, delim);
324 trace_seq_printf(p, "0x%lx", flags);
325 }
326
327 trace_seq_putc(p, 0);
328
329 return ret;
330 }
331 EXPORT_SYMBOL(ftrace_print_flags_seq);
332
333 const char *
334 ftrace_print_symbols_seq(struct trace_seq *p, unsigned long val,
335 const struct trace_print_flags *symbol_array)
336 {
337 int i;
338 const char *ret = p->buffer + p->len;
339
340 for (i = 0; symbol_array[i].name; i++) {
341
342 if (val != symbol_array[i].mask)
343 continue;
344
345 trace_seq_puts(p, symbol_array[i].name);
346 break;
347 }
348
349 if (ret == (const char *)(p->buffer + p->len))
350 trace_seq_printf(p, "0x%lx", val);
351
352 trace_seq_putc(p, 0);
353
354 return ret;
355 }
356 EXPORT_SYMBOL(ftrace_print_symbols_seq);
357
358 #if BITS_PER_LONG == 32
359 const char *
360 ftrace_print_symbols_seq_u64(struct trace_seq *p, unsigned long long val,
361 const struct trace_print_flags_u64 *symbol_array)
362 {
363 int i;
364 const char *ret = p->buffer + p->len;
365
366 for (i = 0; symbol_array[i].name; i++) {
367
368 if (val != symbol_array[i].mask)
369 continue;
370
371 trace_seq_puts(p, symbol_array[i].name);
372 break;
373 }
374
375 if (ret == (const char *)(p->buffer + p->len))
376 trace_seq_printf(p, "0x%llx", val);
377
378 trace_seq_putc(p, 0);
379
380 return ret;
381 }
382 EXPORT_SYMBOL(ftrace_print_symbols_seq_u64);
383 #endif
384
385 const char *
386 ftrace_print_hex_seq(struct trace_seq *p, const unsigned char *buf, int buf_len)
387 {
388 int i;
389 const char *ret = p->buffer + p->len;
390
391 for (i = 0; i < buf_len; i++)
392 trace_seq_printf(p, "%s%2.2x", i == 0 ? "" : " ", buf[i]);
393
394 trace_seq_putc(p, 0);
395
396 return ret;
397 }
398 EXPORT_SYMBOL(ftrace_print_hex_seq);
399
400 #ifdef CONFIG_KRETPROBES
401 static inline const char *kretprobed(const char *name)
402 {
403 static const char tramp_name[] = "kretprobe_trampoline";
404 int size = sizeof(tramp_name);
405
406 if (strncmp(tramp_name, name, size) == 0)
407 return "[unknown/kretprobe'd]";
408 return name;
409 }
410 #else
411 static inline const char *kretprobed(const char *name)
412 {
413 return name;
414 }
415 #endif /* CONFIG_KRETPROBES */
416
417 static int
418 seq_print_sym_short(struct trace_seq *s, const char *fmt, unsigned long address)
419 {
420 #ifdef CONFIG_KALLSYMS
421 char str[KSYM_SYMBOL_LEN];
422 const char *name;
423
424 kallsyms_lookup(address, NULL, NULL, NULL, str);
425
426 name = kretprobed(str);
427
428 return trace_seq_printf(s, fmt, name);
429 #endif
430 return 1;
431 }
432
433 static int
434 seq_print_sym_offset(struct trace_seq *s, const char *fmt,
435 unsigned long address)
436 {
437 #ifdef CONFIG_KALLSYMS
438 char str[KSYM_SYMBOL_LEN];
439 const char *name;
440
441 sprint_symbol(str, address);
442 name = kretprobed(str);
443
444 return trace_seq_printf(s, fmt, name);
445 #endif
446 return 1;
447 }
448
449 #ifndef CONFIG_64BIT
450 # define IP_FMT "%08lx"
451 #else
452 # define IP_FMT "%016lx"
453 #endif
454
455 int seq_print_user_ip(struct trace_seq *s, struct mm_struct *mm,
456 unsigned long ip, unsigned long sym_flags)
457 {
458 struct file *file = NULL;
459 unsigned long vmstart = 0;
460 int ret = 1;
461
462 if (s->full)
463 return 0;
464
465 if (mm) {
466 const struct vm_area_struct *vma;
467
468 down_read(&mm->mmap_sem);
469 vma = find_vma(mm, ip);
470 if (vma) {
471 file = vma->vm_file;
472 vmstart = vma->vm_start;
473 }
474 if (file) {
475 ret = trace_seq_path(s, &file->f_path);
476 if (ret)
477 ret = trace_seq_printf(s, "[+0x%lx]",
478 ip - vmstart);
479 }
480 up_read(&mm->mmap_sem);
481 }
482 if (ret && ((sym_flags & TRACE_ITER_SYM_ADDR) || !file))
483 ret = trace_seq_printf(s, " <" IP_FMT ">", ip);
484 return ret;
485 }
486
487 int
488 seq_print_userip_objs(const struct userstack_entry *entry, struct trace_seq *s,
489 unsigned long sym_flags)
490 {
491 struct mm_struct *mm = NULL;
492 int ret = 1;
493 unsigned int i;
494
495 if (trace_flags & TRACE_ITER_SYM_USEROBJ) {
496 struct task_struct *task;
497 /*
498 * we do the lookup on the thread group leader,
499 * since individual threads might have already quit!
500 */
501 rcu_read_lock();
502 task = find_task_by_vpid(entry->tgid);
503 if (task)
504 mm = get_task_mm(task);
505 rcu_read_unlock();
506 }
507
508 for (i = 0; i < FTRACE_STACK_ENTRIES; i++) {
509 unsigned long ip = entry->caller[i];
510
511 if (ip == ULONG_MAX || !ret)
512 break;
513 if (ret)
514 ret = trace_seq_puts(s, " => ");
515 if (!ip) {
516 if (ret)
517 ret = trace_seq_puts(s, "??");
518 if (ret)
519 ret = trace_seq_puts(s, "\n");
520 continue;
521 }
522 if (!ret)
523 break;
524 if (ret)
525 ret = seq_print_user_ip(s, mm, ip, sym_flags);
526 ret = trace_seq_puts(s, "\n");
527 }
528
529 if (mm)
530 mmput(mm);
531 return ret;
532 }
533
534 int
535 seq_print_ip_sym(struct trace_seq *s, unsigned long ip, unsigned long sym_flags)
536 {
537 int ret;
538
539 if (!ip)
540 return trace_seq_printf(s, "0");
541
542 if (sym_flags & TRACE_ITER_SYM_OFFSET)
543 ret = seq_print_sym_offset(s, "%s", ip);
544 else
545 ret = seq_print_sym_short(s, "%s", ip);
546
547 if (!ret)
548 return 0;
549
550 if (sym_flags & TRACE_ITER_SYM_ADDR)
551 ret = trace_seq_printf(s, " <" IP_FMT ">", ip);
552 return ret;
553 }
554
555 /**
556 * trace_print_lat_fmt - print the irq, preempt and lockdep fields
557 * @s: trace seq struct to write to
558 * @entry: The trace entry field from the ring buffer
559 *
560 * Prints the generic fields of irqs off, in hard or softirq, preempt
561 * count.
562 */
563 int trace_print_lat_fmt(struct trace_seq *s, struct trace_entry *entry)
564 {
565 char hardsoft_irq;
566 char need_resched;
567 char irqs_off;
568 int hardirq;
569 int softirq;
570 int ret;
571
572 hardirq = entry->flags & TRACE_FLAG_HARDIRQ;
573 softirq = entry->flags & TRACE_FLAG_SOFTIRQ;
574
575 irqs_off =
576 (entry->flags & TRACE_FLAG_IRQS_OFF) ? 'd' :
577 (entry->flags & TRACE_FLAG_IRQS_NOSUPPORT) ? 'X' :
578 '.';
579 need_resched =
580 (entry->flags & TRACE_FLAG_NEED_RESCHED) ? 'N' : '.';
581 hardsoft_irq =
582 (hardirq && softirq) ? 'H' :
583 hardirq ? 'h' :
584 softirq ? 's' :
585 '.';
586
587 if (!trace_seq_printf(s, "%c%c%c",
588 irqs_off, need_resched, hardsoft_irq))
589 return 0;
590
591 if (entry->preempt_count)
592 ret = trace_seq_printf(s, "%x", entry->preempt_count);
593 else
594 ret = trace_seq_putc(s, '.');
595
596 return ret;
597 }
598
599 static int
600 lat_print_generic(struct trace_seq *s, struct trace_entry *entry, int cpu)
601 {
602 char comm[TASK_COMM_LEN];
603
604 trace_find_cmdline(entry->pid, comm);
605
606 if (!trace_seq_printf(s, "%8.8s-%-5d %3d",
607 comm, entry->pid, cpu))
608 return 0;
609
610 return trace_print_lat_fmt(s, entry);
611 }
612
613 static unsigned long preempt_mark_thresh = 100;
614
615 static int
616 lat_print_timestamp(struct trace_seq *s, u64 abs_usecs,
617 unsigned long rel_usecs)
618 {
619 return trace_seq_printf(s, " %4lldus%c: ", abs_usecs,
620 rel_usecs > preempt_mark_thresh ? '!' :
621 rel_usecs > 1 ? '+' : ' ');
622 }
623
624 int trace_print_context(struct trace_iterator *iter)
625 {
626 struct trace_seq *s = &iter->seq;
627 struct trace_entry *entry = iter->ent;
628 unsigned long long t = ns2usecs(iter->ts);
629 unsigned long usec_rem = do_div(t, USEC_PER_SEC);
630 unsigned long secs = (unsigned long)t;
631 char comm[TASK_COMM_LEN];
632 int ret;
633
634 trace_find_cmdline(entry->pid, comm);
635
636 ret = trace_seq_printf(s, "%16s-%-5d [%03d] ",
637 comm, entry->pid, iter->cpu);
638 if (!ret)
639 return 0;
640
641 if (trace_flags & TRACE_ITER_IRQ_INFO) {
642 ret = trace_print_lat_fmt(s, entry);
643 if (!ret)
644 return 0;
645 }
646
647 return trace_seq_printf(s, " %5lu.%06lu: ",
648 secs, usec_rem);
649 }
650
651 int trace_print_lat_context(struct trace_iterator *iter)
652 {
653 u64 next_ts;
654 int ret;
655 /* trace_find_next_entry will reset ent_size */
656 int ent_size = iter->ent_size;
657 struct trace_seq *s = &iter->seq;
658 struct trace_entry *entry = iter->ent,
659 *next_entry = trace_find_next_entry(iter, NULL,
660 &next_ts);
661 unsigned long verbose = (trace_flags & TRACE_ITER_VERBOSE);
662 unsigned long abs_usecs = ns2usecs(iter->ts - iter->tr->time_start);
663 unsigned long rel_usecs;
664
665 /* Restore the original ent_size */
666 iter->ent_size = ent_size;
667
668 if (!next_entry)
669 next_ts = iter->ts;
670 rel_usecs = ns2usecs(next_ts - iter->ts);
671
672 if (verbose) {
673 char comm[TASK_COMM_LEN];
674
675 trace_find_cmdline(entry->pid, comm);
676
677 ret = trace_seq_printf(s, "%16s %5d %3d %d %08x %08lx [%08llx]"
678 " %ld.%03ldms (+%ld.%03ldms): ", comm,
679 entry->pid, iter->cpu, entry->flags,
680 entry->preempt_count, iter->idx,
681 ns2usecs(iter->ts),
682 abs_usecs / USEC_PER_MSEC,
683 abs_usecs % USEC_PER_MSEC,
684 rel_usecs / USEC_PER_MSEC,
685 rel_usecs % USEC_PER_MSEC);
686 } else {
687 ret = lat_print_generic(s, entry, iter->cpu);
688 if (ret)
689 ret = lat_print_timestamp(s, abs_usecs, rel_usecs);
690 }
691
692 return ret;
693 }
694
695 static const char state_to_char[] = TASK_STATE_TO_CHAR_STR;
696
697 static int task_state_char(unsigned long state)
698 {
699 int bit = state ? __ffs(state) + 1 : 0;
700
701 return bit < sizeof(state_to_char) - 1 ? state_to_char[bit] : '?';
702 }
703
704 /**
705 * ftrace_find_event - find a registered event
706 * @type: the type of event to look for
707 *
708 * Returns an event of type @type otherwise NULL
709 * Called with trace_event_read_lock() held.
710 */
711 struct trace_event *ftrace_find_event(int type)
712 {
713 struct trace_event *event;
714 struct hlist_node *n;
715 unsigned key;
716
717 key = type & (EVENT_HASHSIZE - 1);
718
719 hlist_for_each_entry(event, n, &event_hash[key], node) {
720 if (event->type == type)
721 return event;
722 }
723
724 return NULL;
725 }
726
727 static LIST_HEAD(ftrace_event_list);
728
729 static int trace_search_list(struct list_head **list)
730 {
731 struct trace_event *e;
732 int last = __TRACE_LAST_TYPE;
733
734 if (list_empty(&ftrace_event_list)) {
735 *list = &ftrace_event_list;
736 return last + 1;
737 }
738
739 /*
740 * We used up all possible max events,
741 * lets see if somebody freed one.
742 */
743 list_for_each_entry(e, &ftrace_event_list, list) {
744 if (e->type != last + 1)
745 break;
746 last++;
747 }
748
749 /* Did we used up all 65 thousand events??? */
750 if ((last + 1) > FTRACE_MAX_EVENT)
751 return 0;
752
753 *list = &e->list;
754 return last + 1;
755 }
756
757 void trace_event_read_lock(void)
758 {
759 down_read(&trace_event_mutex);
760 }
761
762 void trace_event_read_unlock(void)
763 {
764 up_read(&trace_event_mutex);
765 }
766
767 /**
768 * register_ftrace_event - register output for an event type
769 * @event: the event type to register
770 *
771 * Event types are stored in a hash and this hash is used to
772 * find a way to print an event. If the @event->type is set
773 * then it will use that type, otherwise it will assign a
774 * type to use.
775 *
776 * If you assign your own type, please make sure it is added
777 * to the trace_type enum in trace.h, to avoid collisions
778 * with the dynamic types.
779 *
780 * Returns the event type number or zero on error.
781 */
782 int register_ftrace_event(struct trace_event *event)
783 {
784 unsigned key;
785 int ret = 0;
786
787 down_write(&trace_event_mutex);
788
789 if (WARN_ON(!event))
790 goto out;
791
792 if (WARN_ON(!event->funcs))
793 goto out;
794
795 INIT_LIST_HEAD(&event->list);
796
797 if (!event->type) {
798 struct list_head *list = NULL;
799
800 if (next_event_type > FTRACE_MAX_EVENT) {
801
802 event->type = trace_search_list(&list);
803 if (!event->type)
804 goto out;
805
806 } else {
807
808 event->type = next_event_type++;
809 list = &ftrace_event_list;
810 }
811
812 if (WARN_ON(ftrace_find_event(event->type)))
813 goto out;
814
815 list_add_tail(&event->list, list);
816
817 } else if (event->type > __TRACE_LAST_TYPE) {
818 printk(KERN_WARNING "Need to add type to trace.h\n");
819 WARN_ON(1);
820 goto out;
821 } else {
822 /* Is this event already used */
823 if (ftrace_find_event(event->type))
824 goto out;
825 }
826
827 if (event->funcs->trace == NULL)
828 event->funcs->trace = trace_nop_print;
829 if (event->funcs->raw == NULL)
830 event->funcs->raw = trace_nop_print;
831 if (event->funcs->hex == NULL)
832 event->funcs->hex = trace_nop_print;
833 if (event->funcs->binary == NULL)
834 event->funcs->binary = trace_nop_print;
835
836 key = event->type & (EVENT_HASHSIZE - 1);
837
838 hlist_add_head(&event->node, &event_hash[key]);
839
840 ret = event->type;
841 out:
842 up_write(&trace_event_mutex);
843
844 return ret;
845 }
846 EXPORT_SYMBOL_GPL(register_ftrace_event);
847
848 /*
849 * Used by module code with the trace_event_mutex held for write.
850 */
851 int __unregister_ftrace_event(struct trace_event *event)
852 {
853 hlist_del(&event->node);
854 list_del(&event->list);
855 return 0;
856 }
857
858 /**
859 * unregister_ftrace_event - remove a no longer used event
860 * @event: the event to remove
861 */
862 int unregister_ftrace_event(struct trace_event *event)
863 {
864 down_write(&trace_event_mutex);
865 __unregister_ftrace_event(event);
866 up_write(&trace_event_mutex);
867
868 return 0;
869 }
870 EXPORT_SYMBOL_GPL(unregister_ftrace_event);
871
872 /*
873 * Standard events
874 */
875
876 enum print_line_t trace_nop_print(struct trace_iterator *iter, int flags,
877 struct trace_event *event)
878 {
879 if (!trace_seq_printf(&iter->seq, "type: %d\n", iter->ent->type))
880 return TRACE_TYPE_PARTIAL_LINE;
881
882 return TRACE_TYPE_HANDLED;
883 }
884
885 /* TRACE_FN */
886 static enum print_line_t trace_fn_trace(struct trace_iterator *iter, int flags,
887 struct trace_event *event)
888 {
889 struct ftrace_entry *field;
890 struct trace_seq *s = &iter->seq;
891
892 trace_assign_type(field, iter->ent);
893
894 if (!seq_print_ip_sym(s, field->ip, flags))
895 goto partial;
896
897 if ((flags & TRACE_ITER_PRINT_PARENT) && field->parent_ip) {
898 if (!trace_seq_printf(s, " <-"))
899 goto partial;
900 if (!seq_print_ip_sym(s,
901 field->parent_ip,
902 flags))
903 goto partial;
904 }
905 if (!trace_seq_printf(s, "\n"))
906 goto partial;
907
908 return TRACE_TYPE_HANDLED;
909
910 partial:
911 return TRACE_TYPE_PARTIAL_LINE;
912 }
913
914 static enum print_line_t trace_fn_raw(struct trace_iterator *iter, int flags,
915 struct trace_event *event)
916 {
917 struct ftrace_entry *field;
918
919 trace_assign_type(field, iter->ent);
920
921 if (!trace_seq_printf(&iter->seq, "%lx %lx\n",
922 field->ip,
923 field->parent_ip))
924 return TRACE_TYPE_PARTIAL_LINE;
925
926 return TRACE_TYPE_HANDLED;
927 }
928
929 static enum print_line_t trace_fn_hex(struct trace_iterator *iter, int flags,
930 struct trace_event *event)
931 {
932 struct ftrace_entry *field;
933 struct trace_seq *s = &iter->seq;
934
935 trace_assign_type(field, iter->ent);
936
937 SEQ_PUT_HEX_FIELD_RET(s, field->ip);
938 SEQ_PUT_HEX_FIELD_RET(s, field->parent_ip);
939
940 return TRACE_TYPE_HANDLED;
941 }
942
943 static enum print_line_t trace_fn_bin(struct trace_iterator *iter, int flags,
944 struct trace_event *event)
945 {
946 struct ftrace_entry *field;
947 struct trace_seq *s = &iter->seq;
948
949 trace_assign_type(field, iter->ent);
950
951 SEQ_PUT_FIELD_RET(s, field->ip);
952 SEQ_PUT_FIELD_RET(s, field->parent_ip);
953
954 return TRACE_TYPE_HANDLED;
955 }
956
957 static struct trace_event_functions trace_fn_funcs = {
958 .trace = trace_fn_trace,
959 .raw = trace_fn_raw,
960 .hex = trace_fn_hex,
961 .binary = trace_fn_bin,
962 };
963
964 static struct trace_event trace_fn_event = {
965 .type = TRACE_FN,
966 .funcs = &trace_fn_funcs,
967 };
968
969 /* TRACE_CTX an TRACE_WAKE */
970 static enum print_line_t trace_ctxwake_print(struct trace_iterator *iter,
971 char *delim)
972 {
973 struct ctx_switch_entry *field;
974 char comm[TASK_COMM_LEN];
975 int S, T;
976
977
978 trace_assign_type(field, iter->ent);
979
980 T = task_state_char(field->next_state);
981 S = task_state_char(field->prev_state);
982 trace_find_cmdline(field->next_pid, comm);
983 if (!trace_seq_printf(&iter->seq,
984 " %5d:%3d:%c %s [%03d] %5d:%3d:%c %s\n",
985 field->prev_pid,
986 field->prev_prio,
987 S, delim,
988 field->next_cpu,
989 field->next_pid,
990 field->next_prio,
991 T, comm))
992 return TRACE_TYPE_PARTIAL_LINE;
993
994 return TRACE_TYPE_HANDLED;
995 }
996
997 static enum print_line_t trace_ctx_print(struct trace_iterator *iter, int flags,
998 struct trace_event *event)
999 {
1000 return trace_ctxwake_print(iter, "==>");
1001 }
1002
1003 static enum print_line_t trace_wake_print(struct trace_iterator *iter,
1004 int flags, struct trace_event *event)
1005 {
1006 return trace_ctxwake_print(iter, " +");
1007 }
1008
1009 static int trace_ctxwake_raw(struct trace_iterator *iter, char S)
1010 {
1011 struct ctx_switch_entry *field;
1012 int T;
1013
1014 trace_assign_type(field, iter->ent);
1015
1016 if (!S)
1017 S = task_state_char(field->prev_state);
1018 T = task_state_char(field->next_state);
1019 if (!trace_seq_printf(&iter->seq, "%d %d %c %d %d %d %c\n",
1020 field->prev_pid,
1021 field->prev_prio,
1022 S,
1023 field->next_cpu,
1024 field->next_pid,
1025 field->next_prio,
1026 T))
1027 return TRACE_TYPE_PARTIAL_LINE;
1028
1029 return TRACE_TYPE_HANDLED;
1030 }
1031
1032 static enum print_line_t trace_ctx_raw(struct trace_iterator *iter, int flags,
1033 struct trace_event *event)
1034 {
1035 return trace_ctxwake_raw(iter, 0);
1036 }
1037
1038 static enum print_line_t trace_wake_raw(struct trace_iterator *iter, int flags,
1039 struct trace_event *event)
1040 {
1041 return trace_ctxwake_raw(iter, '+');
1042 }
1043
1044
1045 static int trace_ctxwake_hex(struct trace_iterator *iter, char S)
1046 {
1047 struct ctx_switch_entry *field;
1048 struct trace_seq *s = &iter->seq;
1049 int T;
1050
1051 trace_assign_type(field, iter->ent);
1052
1053 if (!S)
1054 S = task_state_char(field->prev_state);
1055 T = task_state_char(field->next_state);
1056
1057 SEQ_PUT_HEX_FIELD_RET(s, field->prev_pid);
1058 SEQ_PUT_HEX_FIELD_RET(s, field->prev_prio);
1059 SEQ_PUT_HEX_FIELD_RET(s, S);
1060 SEQ_PUT_HEX_FIELD_RET(s, field->next_cpu);
1061 SEQ_PUT_HEX_FIELD_RET(s, field->next_pid);
1062 SEQ_PUT_HEX_FIELD_RET(s, field->next_prio);
1063 SEQ_PUT_HEX_FIELD_RET(s, T);
1064
1065 return TRACE_TYPE_HANDLED;
1066 }
1067
1068 static enum print_line_t trace_ctx_hex(struct trace_iterator *iter, int flags,
1069 struct trace_event *event)
1070 {
1071 return trace_ctxwake_hex(iter, 0);
1072 }
1073
1074 static enum print_line_t trace_wake_hex(struct trace_iterator *iter, int flags,
1075 struct trace_event *event)
1076 {
1077 return trace_ctxwake_hex(iter, '+');
1078 }
1079
1080 static enum print_line_t trace_ctxwake_bin(struct trace_iterator *iter,
1081 int flags, struct trace_event *event)
1082 {
1083 struct ctx_switch_entry *field;
1084 struct trace_seq *s = &iter->seq;
1085
1086 trace_assign_type(field, iter->ent);
1087
1088 SEQ_PUT_FIELD_RET(s, field->prev_pid);
1089 SEQ_PUT_FIELD_RET(s, field->prev_prio);
1090 SEQ_PUT_FIELD_RET(s, field->prev_state);
1091 SEQ_PUT_FIELD_RET(s, field->next_pid);
1092 SEQ_PUT_FIELD_RET(s, field->next_prio);
1093 SEQ_PUT_FIELD_RET(s, field->next_state);
1094
1095 return TRACE_TYPE_HANDLED;
1096 }
1097
1098 static struct trace_event_functions trace_ctx_funcs = {
1099 .trace = trace_ctx_print,
1100 .raw = trace_ctx_raw,
1101 .hex = trace_ctx_hex,
1102 .binary = trace_ctxwake_bin,
1103 };
1104
1105 static struct trace_event trace_ctx_event = {
1106 .type = TRACE_CTX,
1107 .funcs = &trace_ctx_funcs,
1108 };
1109
1110 static struct trace_event_functions trace_wake_funcs = {
1111 .trace = trace_wake_print,
1112 .raw = trace_wake_raw,
1113 .hex = trace_wake_hex,
1114 .binary = trace_ctxwake_bin,
1115 };
1116
1117 static struct trace_event trace_wake_event = {
1118 .type = TRACE_WAKE,
1119 .funcs = &trace_wake_funcs,
1120 };
1121
1122 /* TRACE_STACK */
1123
1124 static enum print_line_t trace_stack_print(struct trace_iterator *iter,
1125 int flags, struct trace_event *event)
1126 {
1127 struct stack_entry *field;
1128 struct trace_seq *s = &iter->seq;
1129 unsigned long *p;
1130 unsigned long *end;
1131
1132 trace_assign_type(field, iter->ent);
1133 end = (unsigned long *)((long)iter->ent + iter->ent_size);
1134
1135 if (!trace_seq_puts(s, "<stack trace>\n"))
1136 goto partial;
1137
1138 for (p = field->caller; p && *p != ULONG_MAX && p < end; p++) {
1139 if (!trace_seq_puts(s, " => "))
1140 goto partial;
1141
1142 if (!seq_print_ip_sym(s, *p, flags))
1143 goto partial;
1144 if (!trace_seq_puts(s, "\n"))
1145 goto partial;
1146 }
1147
1148 return TRACE_TYPE_HANDLED;
1149
1150 partial:
1151 return TRACE_TYPE_PARTIAL_LINE;
1152 }
1153
1154 static struct trace_event_functions trace_stack_funcs = {
1155 .trace = trace_stack_print,
1156 };
1157
1158 static struct trace_event trace_stack_event = {
1159 .type = TRACE_STACK,
1160 .funcs = &trace_stack_funcs,
1161 };
1162
1163 /* TRACE_USER_STACK */
1164 static enum print_line_t trace_user_stack_print(struct trace_iterator *iter,
1165 int flags, struct trace_event *event)
1166 {
1167 struct userstack_entry *field;
1168 struct trace_seq *s = &iter->seq;
1169
1170 trace_assign_type(field, iter->ent);
1171
1172 if (!trace_seq_puts(s, "<user stack trace>\n"))
1173 goto partial;
1174
1175 if (!seq_print_userip_objs(field, s, flags))
1176 goto partial;
1177
1178 return TRACE_TYPE_HANDLED;
1179
1180 partial:
1181 return TRACE_TYPE_PARTIAL_LINE;
1182 }
1183
1184 static struct trace_event_functions trace_user_stack_funcs = {
1185 .trace = trace_user_stack_print,
1186 };
1187
1188 static struct trace_event trace_user_stack_event = {
1189 .type = TRACE_USER_STACK,
1190 .funcs = &trace_user_stack_funcs,
1191 };
1192
1193 /* TRACE_BPRINT */
1194 static enum print_line_t
1195 trace_bprint_print(struct trace_iterator *iter, int flags,
1196 struct trace_event *event)
1197 {
1198 struct trace_entry *entry = iter->ent;
1199 struct trace_seq *s = &iter->seq;
1200 struct bprint_entry *field;
1201
1202 trace_assign_type(field, entry);
1203
1204 if (!seq_print_ip_sym(s, field->ip, flags))
1205 goto partial;
1206
1207 if (!trace_seq_puts(s, ": "))
1208 goto partial;
1209
1210 if (!trace_seq_bprintf(s, field->fmt, field->buf))
1211 goto partial;
1212
1213 return TRACE_TYPE_HANDLED;
1214
1215 partial:
1216 return TRACE_TYPE_PARTIAL_LINE;
1217 }
1218
1219
1220 static enum print_line_t
1221 trace_bprint_raw(struct trace_iterator *iter, int flags,
1222 struct trace_event *event)
1223 {
1224 struct bprint_entry *field;
1225 struct trace_seq *s = &iter->seq;
1226
1227 trace_assign_type(field, iter->ent);
1228
1229 if (!trace_seq_printf(s, ": %lx : ", field->ip))
1230 goto partial;
1231
1232 if (!trace_seq_bprintf(s, field->fmt, field->buf))
1233 goto partial;
1234
1235 return TRACE_TYPE_HANDLED;
1236
1237 partial:
1238 return TRACE_TYPE_PARTIAL_LINE;
1239 }
1240
1241 static struct trace_event_functions trace_bprint_funcs = {
1242 .trace = trace_bprint_print,
1243 .raw = trace_bprint_raw,
1244 };
1245
1246 static struct trace_event trace_bprint_event = {
1247 .type = TRACE_BPRINT,
1248 .funcs = &trace_bprint_funcs,
1249 };
1250
1251 /* TRACE_PRINT */
1252 static enum print_line_t trace_print_print(struct trace_iterator *iter,
1253 int flags, struct trace_event *event)
1254 {
1255 struct print_entry *field;
1256 struct trace_seq *s = &iter->seq;
1257
1258 trace_assign_type(field, iter->ent);
1259
1260 if (!seq_print_ip_sym(s, field->ip, flags))
1261 goto partial;
1262
1263 if (!trace_seq_printf(s, ": %s", field->buf))
1264 goto partial;
1265
1266 return TRACE_TYPE_HANDLED;
1267
1268 partial:
1269 return TRACE_TYPE_PARTIAL_LINE;
1270 }
1271
1272 static enum print_line_t trace_print_raw(struct trace_iterator *iter, int flags,
1273 struct trace_event *event)
1274 {
1275 struct print_entry *field;
1276
1277 trace_assign_type(field, iter->ent);
1278
1279 if (!trace_seq_printf(&iter->seq, "# %lx %s", field->ip, field->buf))
1280 goto partial;
1281
1282 return TRACE_TYPE_HANDLED;
1283
1284 partial:
1285 return TRACE_TYPE_PARTIAL_LINE;
1286 }
1287
1288 static struct trace_event_functions trace_print_funcs = {
1289 .trace = trace_print_print,
1290 .raw = trace_print_raw,
1291 };
1292
1293 static struct trace_event trace_print_event = {
1294 .type = TRACE_PRINT,
1295 .funcs = &trace_print_funcs,
1296 };
1297
1298
1299 static struct trace_event *events[] __initdata = {
1300 &trace_fn_event,
1301 &trace_ctx_event,
1302 &trace_wake_event,
1303 &trace_stack_event,
1304 &trace_user_stack_event,
1305 &trace_bprint_event,
1306 &trace_print_event,
1307 NULL
1308 };
1309
1310 __init static int init_events(void)
1311 {
1312 struct trace_event *event;
1313 int i, ret;
1314
1315 for (i = 0; events[i]; i++) {
1316 event = events[i];
1317
1318 ret = register_ftrace_event(event);
1319 if (!ret) {
1320 printk(KERN_WARNING "event %d failed to register\n",
1321 event->type);
1322 WARN_ON_ONCE(1);
1323 }
1324 }
1325
1326 return 0;
1327 }
1328 device_initcall(init_events);
1329