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Linux 4.19-rc7
[linux-2.6/btrfs-unstable.git] / kernel / trace / trace_output.c
blob6e6cc64faa389b72012f58912a32114ad45cf704
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * trace_output.c
4 *
5 * Copyright (C) 2008 Red Hat Inc, Steven Rostedt <srostedt@redhat.com>
6 *
7 */
8 #include <linux/module.h>
9 #include <linux/mutex.h>
10 #include <linux/ftrace.h>
11 #include <linux/sched/clock.h>
12 #include <linux/sched/mm.h>
13
14 #include "trace_output.h"
15
16 /* must be a power of 2 */
17 #define EVENT_HASHSIZE 128
18
19 DECLARE_RWSEM(trace_event_sem);
20
21 static struct hlist_head event_hash[EVENT_HASHSIZE] __read_mostly;
22
23 static int next_event_type = __TRACE_LAST_TYPE + 1;
24
25 enum print_line_t trace_print_bputs_msg_only(struct trace_iterator *iter)
26 {
27 struct trace_seq *s = &iter->seq;
28 struct trace_entry *entry = iter->ent;
29 struct bputs_entry *field;
30
31 trace_assign_type(field, entry);
32
33 trace_seq_puts(s, field->str);
34
35 return trace_handle_return(s);
36 }
37
38 enum print_line_t trace_print_bprintk_msg_only(struct trace_iterator *iter)
39 {
40 struct trace_seq *s = &iter->seq;
41 struct trace_entry *entry = iter->ent;
42 struct bprint_entry *field;
43
44 trace_assign_type(field, entry);
45
46 trace_seq_bprintf(s, field->fmt, field->buf);
47
48 return trace_handle_return(s);
49 }
50
51 enum print_line_t trace_print_printk_msg_only(struct trace_iterator *iter)
52 {
53 struct trace_seq *s = &iter->seq;
54 struct trace_entry *entry = iter->ent;
55 struct print_entry *field;
56
57 trace_assign_type(field, entry);
58
59 trace_seq_puts(s, field->buf);
60
61 return trace_handle_return(s);
62 }
63
64 const char *
65 trace_print_flags_seq(struct trace_seq *p, const char *delim,
66 unsigned long flags,
67 const struct trace_print_flags *flag_array)
68 {
69 unsigned long mask;
70 const char *str;
71 const char *ret = trace_seq_buffer_ptr(p);
72 int i, first = 1;
73
74 for (i = 0; flag_array[i].name && flags; i++) {
75
76 mask = flag_array[i].mask;
77 if ((flags & mask) != mask)
78 continue;
79
80 str = flag_array[i].name;
81 flags &= ~mask;
82 if (!first && delim)
83 trace_seq_puts(p, delim);
84 else
85 first = 0;
86 trace_seq_puts(p, str);
87 }
88
89 /* check for left over flags */
90 if (flags) {
91 if (!first && delim)
92 trace_seq_puts(p, delim);
93 trace_seq_printf(p, "0x%lx", flags);
94 }
95
96 trace_seq_putc(p, 0);
97
98 return ret;
99 }
100 EXPORT_SYMBOL(trace_print_flags_seq);
101
102 const char *
103 trace_print_symbols_seq(struct trace_seq *p, unsigned long val,
104 const struct trace_print_flags *symbol_array)
105 {
106 int i;
107 const char *ret = trace_seq_buffer_ptr(p);
108
109 for (i = 0; symbol_array[i].name; i++) {
110
111 if (val != symbol_array[i].mask)
112 continue;
113
114 trace_seq_puts(p, symbol_array[i].name);
115 break;
116 }
117
118 if (ret == (const char *)(trace_seq_buffer_ptr(p)))
119 trace_seq_printf(p, "0x%lx", val);
120
121 trace_seq_putc(p, 0);
122
123 return ret;
124 }
125 EXPORT_SYMBOL(trace_print_symbols_seq);
126
127 #if BITS_PER_LONG == 32
128 const char *
129 trace_print_flags_seq_u64(struct trace_seq *p, const char *delim,
130 unsigned long long flags,
131 const struct trace_print_flags_u64 *flag_array)
132 {
133 unsigned long long mask;
134 const char *str;
135 const char *ret = trace_seq_buffer_ptr(p);
136 int i, first = 1;
137
138 for (i = 0; flag_array[i].name && flags; i++) {
139
140 mask = flag_array[i].mask;
141 if ((flags & mask) != mask)
142 continue;
143
144 str = flag_array[i].name;
145 flags &= ~mask;
146 if (!first && delim)
147 trace_seq_puts(p, delim);
148 else
149 first = 0;
150 trace_seq_puts(p, str);
151 }
152
153 /* check for left over flags */
154 if (flags) {
155 if (!first && delim)
156 trace_seq_puts(p, delim);
157 trace_seq_printf(p, "0x%llx", flags);
158 }
159
160 trace_seq_putc(p, 0);
161
162 return ret;
163 }
164 EXPORT_SYMBOL(trace_print_flags_seq_u64);
165
166 const char *
167 trace_print_symbols_seq_u64(struct trace_seq *p, unsigned long long val,
168 const struct trace_print_flags_u64 *symbol_array)
169 {
170 int i;
171 const char *ret = trace_seq_buffer_ptr(p);
172
173 for (i = 0; symbol_array[i].name; i++) {
174
175 if (val != symbol_array[i].mask)
176 continue;
177
178 trace_seq_puts(p, symbol_array[i].name);
179 break;
180 }
181
182 if (ret == (const char *)(trace_seq_buffer_ptr(p)))
183 trace_seq_printf(p, "0x%llx", val);
184
185 trace_seq_putc(p, 0);
186
187 return ret;
188 }
189 EXPORT_SYMBOL(trace_print_symbols_seq_u64);
190 #endif
191
192 const char *
193 trace_print_bitmask_seq(struct trace_seq *p, void *bitmask_ptr,
194 unsigned int bitmask_size)
195 {
196 const char *ret = trace_seq_buffer_ptr(p);
197
198 trace_seq_bitmask(p, bitmask_ptr, bitmask_size * 8);
199 trace_seq_putc(p, 0);
200
201 return ret;
202 }
203 EXPORT_SYMBOL_GPL(trace_print_bitmask_seq);
204
205 /**
206 * trace_print_hex_seq - print buffer as hex sequence
207 * @p: trace seq struct to write to
208 * @buf: The buffer to print
209 * @buf_len: Length of @buf in bytes
210 * @concatenate: Print @buf as single hex string or with spacing
211 *
212 * Prints the passed buffer as a hex sequence either as a whole,
213 * single hex string if @concatenate is true or with spacing after
214 * each byte in case @concatenate is false.
215 */
216 const char *
217 trace_print_hex_seq(struct trace_seq *p, const unsigned char *buf, int buf_len,
218 bool concatenate)
219 {
220 int i;
221 const char *ret = trace_seq_buffer_ptr(p);
222
223 for (i = 0; i < buf_len; i++)
224 trace_seq_printf(p, "%s%2.2x", concatenate || i == 0 ? "" : " ",
225 buf[i]);
226 trace_seq_putc(p, 0);
227
228 return ret;
229 }
230 EXPORT_SYMBOL(trace_print_hex_seq);
231
232 const char *
233 trace_print_array_seq(struct trace_seq *p, const void *buf, int count,
234 size_t el_size)
235 {
236 const char *ret = trace_seq_buffer_ptr(p);
237 const char *prefix = "";
238 void *ptr = (void *)buf;
239 size_t buf_len = count * el_size;
240
241 trace_seq_putc(p, '{');
242
243 while (ptr < buf + buf_len) {
244 switch (el_size) {
245 case 1:
246 trace_seq_printf(p, "%s0x%x", prefix,
247 *(u8 *)ptr);
248 break;
249 case 2:
250 trace_seq_printf(p, "%s0x%x", prefix,
251 *(u16 *)ptr);
252 break;
253 case 4:
254 trace_seq_printf(p, "%s0x%x", prefix,
255 *(u32 *)ptr);
256 break;
257 case 8:
258 trace_seq_printf(p, "%s0x%llx", prefix,
259 *(u64 *)ptr);
260 break;
261 default:
262 trace_seq_printf(p, "BAD SIZE:%zu 0x%x", el_size,
263 *(u8 *)ptr);
264 el_size = 1;
265 }
266 prefix = ",";
267 ptr += el_size;
268 }
269
270 trace_seq_putc(p, '}');
271 trace_seq_putc(p, 0);
272
273 return ret;
274 }
275 EXPORT_SYMBOL(trace_print_array_seq);
276
277 int trace_raw_output_prep(struct trace_iterator *iter,
278 struct trace_event *trace_event)
279 {
280 struct trace_event_call *event;
281 struct trace_seq *s = &iter->seq;
282 struct trace_seq *p = &iter->tmp_seq;
283 struct trace_entry *entry;
284
285 event = container_of(trace_event, struct trace_event_call, event);
286 entry = iter->ent;
287
288 if (entry->type != event->event.type) {
289 WARN_ON_ONCE(1);
290 return TRACE_TYPE_UNHANDLED;
291 }
292
293 trace_seq_init(p);
294 trace_seq_printf(s, "%s: ", trace_event_name(event));
295
296 return trace_handle_return(s);
297 }
298 EXPORT_SYMBOL(trace_raw_output_prep);
299
300 static int trace_output_raw(struct trace_iterator *iter, char *name,
301 char *fmt, va_list ap)
302 {
303 struct trace_seq *s = &iter->seq;
304
305 trace_seq_printf(s, "%s: ", name);
306 trace_seq_vprintf(s, fmt, ap);
307
308 return trace_handle_return(s);
309 }
310
311 int trace_output_call(struct trace_iterator *iter, char *name, char *fmt, ...)
312 {
313 va_list ap;
314 int ret;
315
316 va_start(ap, fmt);
317 ret = trace_output_raw(iter, name, fmt, ap);
318 va_end(ap);
319
320 return ret;
321 }
322 EXPORT_SYMBOL_GPL(trace_output_call);
323
324 #ifdef CONFIG_KRETPROBES
325 static inline const char *kretprobed(const char *name)
326 {
327 static const char tramp_name[] = "kretprobe_trampoline";
328 int size = sizeof(tramp_name);
329
330 if (strncmp(tramp_name, name, size) == 0)
331 return "[unknown/kretprobe'd]";
332 return name;
333 }
334 #else
335 static inline const char *kretprobed(const char *name)
336 {
337 return name;
338 }
339 #endif /* CONFIG_KRETPROBES */
340
341 static void
342 seq_print_sym_short(struct trace_seq *s, const char *fmt, unsigned long address)
343 {
344 char str[KSYM_SYMBOL_LEN];
345 #ifdef CONFIG_KALLSYMS
346 const char *name;
347
348 kallsyms_lookup(address, NULL, NULL, NULL, str);
349
350 name = kretprobed(str);
351
352 if (name && strlen(name)) {
353 trace_seq_printf(s, fmt, name);
354 return;
355 }
356 #endif
357 snprintf(str, KSYM_SYMBOL_LEN, "0x%08lx", address);
358 trace_seq_printf(s, fmt, str);
359 }
360
361 static void
362 seq_print_sym_offset(struct trace_seq *s, const char *fmt,
363 unsigned long address)
364 {
365 char str[KSYM_SYMBOL_LEN];
366 #ifdef CONFIG_KALLSYMS
367 const char *name;
368
369 sprint_symbol(str, address);
370 name = kretprobed(str);
371
372 if (name && strlen(name)) {
373 trace_seq_printf(s, fmt, name);
374 return;
375 }
376 #endif
377 snprintf(str, KSYM_SYMBOL_LEN, "0x%08lx", address);
378 trace_seq_printf(s, fmt, str);
379 }
380
381 #ifndef CONFIG_64BIT
382 # define IP_FMT "%08lx"
383 #else
384 # define IP_FMT "%016lx"
385 #endif
386
387 static int seq_print_user_ip(struct trace_seq *s, struct mm_struct *mm,
388 unsigned long ip, unsigned long sym_flags)
389 {
390 struct file *file = NULL;
391 unsigned long vmstart = 0;
392 int ret = 1;
393
394 if (s->full)
395 return 0;
396
397 if (mm) {
398 const struct vm_area_struct *vma;
399
400 down_read(&mm->mmap_sem);
401 vma = find_vma(mm, ip);
402 if (vma) {
403 file = vma->vm_file;
404 vmstart = vma->vm_start;
405 }
406 if (file) {
407 ret = trace_seq_path(s, &file->f_path);
408 if (ret)
409 trace_seq_printf(s, "[+0x%lx]",
410 ip - vmstart);
411 }
412 up_read(&mm->mmap_sem);
413 }
414 if (ret && ((sym_flags & TRACE_ITER_SYM_ADDR) || !file))
415 trace_seq_printf(s, " <" IP_FMT ">", ip);
416 return !trace_seq_has_overflowed(s);
417 }
418
419 int
420 seq_print_ip_sym(struct trace_seq *s, unsigned long ip, unsigned long sym_flags)
421 {
422 if (!ip) {
423 trace_seq_putc(s, '0');
424 goto out;
425 }
426
427 if (sym_flags & TRACE_ITER_SYM_OFFSET)
428 seq_print_sym_offset(s, "%s", ip);
429 else
430 seq_print_sym_short(s, "%s", ip);
431
432 if (sym_flags & TRACE_ITER_SYM_ADDR)
433 trace_seq_printf(s, " <" IP_FMT ">", ip);
434
435 out:
436 return !trace_seq_has_overflowed(s);
437 }
438
439 /**
440 * trace_print_lat_fmt - print the irq, preempt and lockdep fields
441 * @s: trace seq struct to write to
442 * @entry: The trace entry field from the ring buffer
443 *
444 * Prints the generic fields of irqs off, in hard or softirq, preempt
445 * count.
446 */
447 int trace_print_lat_fmt(struct trace_seq *s, struct trace_entry *entry)
448 {
449 char hardsoft_irq;
450 char need_resched;
451 char irqs_off;
452 int hardirq;
453 int softirq;
454 int nmi;
455
456 nmi = entry->flags & TRACE_FLAG_NMI;
457 hardirq = entry->flags & TRACE_FLAG_HARDIRQ;
458 softirq = entry->flags & TRACE_FLAG_SOFTIRQ;
459
460 irqs_off =
461 (entry->flags & TRACE_FLAG_IRQS_OFF) ? 'd' :
462 (entry->flags & TRACE_FLAG_IRQS_NOSUPPORT) ? 'X' :
463 '.';
464
465 switch (entry->flags & (TRACE_FLAG_NEED_RESCHED |
466 TRACE_FLAG_PREEMPT_RESCHED)) {
467 case TRACE_FLAG_NEED_RESCHED | TRACE_FLAG_PREEMPT_RESCHED:
468 need_resched = 'N';
469 break;
470 case TRACE_FLAG_NEED_RESCHED:
471 need_resched = 'n';
472 break;
473 case TRACE_FLAG_PREEMPT_RESCHED:
474 need_resched = 'p';
475 break;
476 default:
477 need_resched = '.';
478 break;
479 }
480
481 hardsoft_irq =
482 (nmi && hardirq) ? 'Z' :
483 nmi ? 'z' :
484 (hardirq && softirq) ? 'H' :
485 hardirq ? 'h' :
486 softirq ? 's' :
487 '.' ;
488
489 trace_seq_printf(s, "%c%c%c",
490 irqs_off, need_resched, hardsoft_irq);
491
492 if (entry->preempt_count)
493 trace_seq_printf(s, "%x", entry->preempt_count);
494 else
495 trace_seq_putc(s, '.');
496
497 return !trace_seq_has_overflowed(s);
498 }
499
500 static int
501 lat_print_generic(struct trace_seq *s, struct trace_entry *entry, int cpu)
502 {
503 char comm[TASK_COMM_LEN];
504
505 trace_find_cmdline(entry->pid, comm);
506
507 trace_seq_printf(s, "%8.8s-%-5d %3d",
508 comm, entry->pid, cpu);
509
510 return trace_print_lat_fmt(s, entry);
511 }
512
513 #undef MARK
514 #define MARK(v, s) {.val = v, .sym = s}
515 /* trace overhead mark */
516 static const struct trace_mark {
517 unsigned long long val; /* unit: nsec */
518 char sym;
519 } mark[] = {
520 MARK(1000000000ULL , '$'), /* 1 sec */
521 MARK(100000000ULL , '@'), /* 100 msec */
522 MARK(10000000ULL , '*'), /* 10 msec */
523 MARK(1000000ULL , '#'), /* 1000 usecs */
524 MARK(100000ULL , '!'), /* 100 usecs */
525 MARK(10000ULL , '+'), /* 10 usecs */
526 };
527 #undef MARK
528
529 char trace_find_mark(unsigned long long d)
530 {
531 int i;
532 int size = ARRAY_SIZE(mark);
533
534 for (i = 0; i < size; i++) {
535 if (d > mark[i].val)
536 break;
537 }
538
539 return (i == size) ? ' ' : mark[i].sym;
540 }
541
542 static int
543 lat_print_timestamp(struct trace_iterator *iter, u64 next_ts)
544 {
545 struct trace_array *tr = iter->tr;
546 unsigned long verbose = tr->trace_flags & TRACE_ITER_VERBOSE;
547 unsigned long in_ns = iter->iter_flags & TRACE_FILE_TIME_IN_NS;
548 unsigned long long abs_ts = iter->ts - iter->trace_buffer->time_start;
549 unsigned long long rel_ts = next_ts - iter->ts;
550 struct trace_seq *s = &iter->seq;
551
552 if (in_ns) {
553 abs_ts = ns2usecs(abs_ts);
554 rel_ts = ns2usecs(rel_ts);
555 }
556
557 if (verbose && in_ns) {
558 unsigned long abs_usec = do_div(abs_ts, USEC_PER_MSEC);
559 unsigned long abs_msec = (unsigned long)abs_ts;
560 unsigned long rel_usec = do_div(rel_ts, USEC_PER_MSEC);
561 unsigned long rel_msec = (unsigned long)rel_ts;
562
563 trace_seq_printf(
564 s, "[%08llx] %ld.%03ldms (+%ld.%03ldms): ",
565 ns2usecs(iter->ts),
566 abs_msec, abs_usec,
567 rel_msec, rel_usec);
568
569 } else if (verbose && !in_ns) {
570 trace_seq_printf(
571 s, "[%016llx] %lld (+%lld): ",
572 iter->ts, abs_ts, rel_ts);
573
574 } else if (!verbose && in_ns) {
575 trace_seq_printf(
576 s, " %4lldus%c: ",
577 abs_ts,
578 trace_find_mark(rel_ts * NSEC_PER_USEC));
579
580 } else { /* !verbose && !in_ns */
581 trace_seq_printf(s, " %4lld: ", abs_ts);
582 }
583
584 return !trace_seq_has_overflowed(s);
585 }
586
587 int trace_print_context(struct trace_iterator *iter)
588 {
589 struct trace_array *tr = iter->tr;
590 struct trace_seq *s = &iter->seq;
591 struct trace_entry *entry = iter->ent;
592 unsigned long long t;
593 unsigned long secs, usec_rem;
594 char comm[TASK_COMM_LEN];
595
596 trace_find_cmdline(entry->pid, comm);
597
598 trace_seq_printf(s, "%16s-%-5d ", comm, entry->pid);
599
600 if (tr->trace_flags & TRACE_ITER_RECORD_TGID) {
601 unsigned int tgid = trace_find_tgid(entry->pid);
602
603 if (!tgid)
604 trace_seq_printf(s, "(-----) ");
605 else
606 trace_seq_printf(s, "(%5d) ", tgid);
607 }
608
609 trace_seq_printf(s, "[%03d] ", iter->cpu);
610
611 if (tr->trace_flags & TRACE_ITER_IRQ_INFO)
612 trace_print_lat_fmt(s, entry);
613
614 if (iter->iter_flags & TRACE_FILE_TIME_IN_NS) {
615 t = ns2usecs(iter->ts);
616 usec_rem = do_div(t, USEC_PER_SEC);
617 secs = (unsigned long)t;
618 trace_seq_printf(s, " %5lu.%06lu: ", secs, usec_rem);
619 } else
620 trace_seq_printf(s, " %12llu: ", iter->ts);
621
622 return !trace_seq_has_overflowed(s);
623 }
624
625 int trace_print_lat_context(struct trace_iterator *iter)
626 {
627 struct trace_array *tr = iter->tr;
628 /* trace_find_next_entry will reset ent_size */
629 int ent_size = iter->ent_size;
630 struct trace_seq *s = &iter->seq;
631 u64 next_ts;
632 struct trace_entry *entry = iter->ent,
633 *next_entry = trace_find_next_entry(iter, NULL,
634 &next_ts);
635 unsigned long verbose = (tr->trace_flags & TRACE_ITER_VERBOSE);
636
637 /* Restore the original ent_size */
638 iter->ent_size = ent_size;
639
640 if (!next_entry)
641 next_ts = iter->ts;
642
643 if (verbose) {
644 char comm[TASK_COMM_LEN];
645
646 trace_find_cmdline(entry->pid, comm);
647
648 trace_seq_printf(
649 s, "%16s %5d %3d %d %08x %08lx ",
650 comm, entry->pid, iter->cpu, entry->flags,
651 entry->preempt_count, iter->idx);
652 } else {
653 lat_print_generic(s, entry, iter->cpu);
654 }
655
656 lat_print_timestamp(iter, next_ts);
657
658 return !trace_seq_has_overflowed(s);
659 }
660
661 /**
662 * ftrace_find_event - find a registered event
663 * @type: the type of event to look for
664 *
665 * Returns an event of type @type otherwise NULL
666 * Called with trace_event_read_lock() held.
667 */
668 struct trace_event *ftrace_find_event(int type)
669 {
670 struct trace_event *event;
671 unsigned key;
672
673 key = type & (EVENT_HASHSIZE - 1);
674
675 hlist_for_each_entry(event, &event_hash[key], node) {
676 if (event->type == type)
677 return event;
678 }
679
680 return NULL;
681 }
682
683 static LIST_HEAD(ftrace_event_list);
684
685 static int trace_search_list(struct list_head **list)
686 {
687 struct trace_event *e;
688 int last = __TRACE_LAST_TYPE;
689
690 if (list_empty(&ftrace_event_list)) {
691 *list = &ftrace_event_list;
692 return last + 1;
693 }
694
695 /*
696 * We used up all possible max events,
697 * lets see if somebody freed one.
698 */
699 list_for_each_entry(e, &ftrace_event_list, list) {
700 if (e->type != last + 1)
701 break;
702 last++;
703 }
704
705 /* Did we used up all 65 thousand events??? */
706 if ((last + 1) > TRACE_EVENT_TYPE_MAX)
707 return 0;
708
709 *list = &e->list;
710 return last + 1;
711 }
712
713 void trace_event_read_lock(void)
714 {
715 down_read(&trace_event_sem);
716 }
717
718 void trace_event_read_unlock(void)
719 {
720 up_read(&trace_event_sem);
721 }
722
723 /**
724 * register_trace_event - register output for an event type
725 * @event: the event type to register
726 *
727 * Event types are stored in a hash and this hash is used to
728 * find a way to print an event. If the @event->type is set
729 * then it will use that type, otherwise it will assign a
730 * type to use.
731 *
732 * If you assign your own type, please make sure it is added
733 * to the trace_type enum in trace.h, to avoid collisions
734 * with the dynamic types.
735 *
736 * Returns the event type number or zero on error.
737 */
738 int register_trace_event(struct trace_event *event)
739 {
740 unsigned key;
741 int ret = 0;
742
743 down_write(&trace_event_sem);
744
745 if (WARN_ON(!event))
746 goto out;
747
748 if (WARN_ON(!event->funcs))
749 goto out;
750
751 INIT_LIST_HEAD(&event->list);
752
753 if (!event->type) {
754 struct list_head *list = NULL;
755
756 if (next_event_type > TRACE_EVENT_TYPE_MAX) {
757
758 event->type = trace_search_list(&list);
759 if (!event->type)
760 goto out;
761
762 } else {
763
764 event->type = next_event_type++;
765 list = &ftrace_event_list;
766 }
767
768 if (WARN_ON(ftrace_find_event(event->type)))
769 goto out;
770
771 list_add_tail(&event->list, list);
772
773 } else if (event->type > __TRACE_LAST_TYPE) {
774 printk(KERN_WARNING "Need to add type to trace.h\n");
775 WARN_ON(1);
776 goto out;
777 } else {
778 /* Is this event already used */
779 if (ftrace_find_event(event->type))
780 goto out;
781 }
782
783 if (event->funcs->trace == NULL)
784 event->funcs->trace = trace_nop_print;
785 if (event->funcs->raw == NULL)
786 event->funcs->raw = trace_nop_print;
787 if (event->funcs->hex == NULL)
788 event->funcs->hex = trace_nop_print;
789 if (event->funcs->binary == NULL)
790 event->funcs->binary = trace_nop_print;
791
792 key = event->type & (EVENT_HASHSIZE - 1);
793
794 hlist_add_head(&event->node, &event_hash[key]);
795
796 ret = event->type;
797 out:
798 up_write(&trace_event_sem);
799
800 return ret;
801 }
802 EXPORT_SYMBOL_GPL(register_trace_event);
803
804 /*
805 * Used by module code with the trace_event_sem held for write.
806 */
807 int __unregister_trace_event(struct trace_event *event)
808 {
809 hlist_del(&event->node);
810 list_del(&event->list);
811 return 0;
812 }
813
814 /**
815 * unregister_trace_event - remove a no longer used event
816 * @event: the event to remove
817 */
818 int unregister_trace_event(struct trace_event *event)
819 {
820 down_write(&trace_event_sem);
821 __unregister_trace_event(event);
822 up_write(&trace_event_sem);
823
824 return 0;
825 }
826 EXPORT_SYMBOL_GPL(unregister_trace_event);
827
828 /*
829 * Standard events
830 */
831
832 enum print_line_t trace_nop_print(struct trace_iterator *iter, int flags,
833 struct trace_event *event)
834 {
835 trace_seq_printf(&iter->seq, "type: %d\n", iter->ent->type);
836
837 return trace_handle_return(&iter->seq);
838 }
839
840 /* TRACE_FN */
841 static enum print_line_t trace_fn_trace(struct trace_iterator *iter, int flags,
842 struct trace_event *event)
843 {
844 struct ftrace_entry *field;
845 struct trace_seq *s = &iter->seq;
846
847 trace_assign_type(field, iter->ent);
848
849 seq_print_ip_sym(s, field->ip, flags);
850
851 if ((flags & TRACE_ITER_PRINT_PARENT) && field->parent_ip) {
852 trace_seq_puts(s, " <-");
853 seq_print_ip_sym(s, field->parent_ip, flags);
854 }
855
856 trace_seq_putc(s, '\n');
857
858 return trace_handle_return(s);
859 }
860
861 static enum print_line_t trace_fn_raw(struct trace_iterator *iter, int flags,
862 struct trace_event *event)
863 {
864 struct ftrace_entry *field;
865
866 trace_assign_type(field, iter->ent);
867
868 trace_seq_printf(&iter->seq, "%lx %lx\n",
869 field->ip,
870 field->parent_ip);
871
872 return trace_handle_return(&iter->seq);
873 }
874
875 static enum print_line_t trace_fn_hex(struct trace_iterator *iter, int flags,
876 struct trace_event *event)
877 {
878 struct ftrace_entry *field;
879 struct trace_seq *s = &iter->seq;
880
881 trace_assign_type(field, iter->ent);
882
883 SEQ_PUT_HEX_FIELD(s, field->ip);
884 SEQ_PUT_HEX_FIELD(s, field->parent_ip);
885
886 return trace_handle_return(s);
887 }
888
889 static enum print_line_t trace_fn_bin(struct trace_iterator *iter, int flags,
890 struct trace_event *event)
891 {
892 struct ftrace_entry *field;
893 struct trace_seq *s = &iter->seq;
894
895 trace_assign_type(field, iter->ent);
896
897 SEQ_PUT_FIELD(s, field->ip);
898 SEQ_PUT_FIELD(s, field->parent_ip);
899
900 return trace_handle_return(s);
901 }
902
903 static struct trace_event_functions trace_fn_funcs = {
904 .trace = trace_fn_trace,
905 .raw = trace_fn_raw,
906 .hex = trace_fn_hex,
907 .binary = trace_fn_bin,
908 };
909
910 static struct trace_event trace_fn_event = {
911 .type = TRACE_FN,
912 .funcs = &trace_fn_funcs,
913 };
914
915 /* TRACE_CTX an TRACE_WAKE */
916 static enum print_line_t trace_ctxwake_print(struct trace_iterator *iter,
917 char *delim)
918 {
919 struct ctx_switch_entry *field;
920 char comm[TASK_COMM_LEN];
921 int S, T;
922
923
924 trace_assign_type(field, iter->ent);
925
926 T = task_index_to_char(field->next_state);
927 S = task_index_to_char(field->prev_state);
928 trace_find_cmdline(field->next_pid, comm);
929 trace_seq_printf(&iter->seq,
930 " %5d:%3d:%c %s [%03d] %5d:%3d:%c %s\n",
931 field->prev_pid,
932 field->prev_prio,
933 S, delim,
934 field->next_cpu,
935 field->next_pid,
936 field->next_prio,
937 T, comm);
938
939 return trace_handle_return(&iter->seq);
940 }
941
942 static enum print_line_t trace_ctx_print(struct trace_iterator *iter, int flags,
943 struct trace_event *event)
944 {
945 return trace_ctxwake_print(iter, "==>");
946 }
947
948 static enum print_line_t trace_wake_print(struct trace_iterator *iter,
949 int flags, struct trace_event *event)
950 {
951 return trace_ctxwake_print(iter, " +");
952 }
953
954 static int trace_ctxwake_raw(struct trace_iterator *iter, char S)
955 {
956 struct ctx_switch_entry *field;
957 int T;
958
959 trace_assign_type(field, iter->ent);
960
961 if (!S)
962 S = task_index_to_char(field->prev_state);
963 T = task_index_to_char(field->next_state);
964 trace_seq_printf(&iter->seq, "%d %d %c %d %d %d %c\n",
965 field->prev_pid,
966 field->prev_prio,
967 S,
968 field->next_cpu,
969 field->next_pid,
970 field->next_prio,
971 T);
972
973 return trace_handle_return(&iter->seq);
974 }
975
976 static enum print_line_t trace_ctx_raw(struct trace_iterator *iter, int flags,
977 struct trace_event *event)
978 {
979 return trace_ctxwake_raw(iter, 0);
980 }
981
982 static enum print_line_t trace_wake_raw(struct trace_iterator *iter, int flags,
983 struct trace_event *event)
984 {
985 return trace_ctxwake_raw(iter, '+');
986 }
987
988
989 static int trace_ctxwake_hex(struct trace_iterator *iter, char S)
990 {
991 struct ctx_switch_entry *field;
992 struct trace_seq *s = &iter->seq;
993 int T;
994
995 trace_assign_type(field, iter->ent);
996
997 if (!S)
998 S = task_index_to_char(field->prev_state);
999 T = task_index_to_char(field->next_state);
1000
1001 SEQ_PUT_HEX_FIELD(s, field->prev_pid);
1002 SEQ_PUT_HEX_FIELD(s, field->prev_prio);
1003 SEQ_PUT_HEX_FIELD(s, S);
1004 SEQ_PUT_HEX_FIELD(s, field->next_cpu);
1005 SEQ_PUT_HEX_FIELD(s, field->next_pid);
1006 SEQ_PUT_HEX_FIELD(s, field->next_prio);
1007 SEQ_PUT_HEX_FIELD(s, T);
1008
1009 return trace_handle_return(s);
1010 }
1011
1012 static enum print_line_t trace_ctx_hex(struct trace_iterator *iter, int flags,
1013 struct trace_event *event)
1014 {
1015 return trace_ctxwake_hex(iter, 0);
1016 }
1017
1018 static enum print_line_t trace_wake_hex(struct trace_iterator *iter, int flags,
1019 struct trace_event *event)
1020 {
1021 return trace_ctxwake_hex(iter, '+');
1022 }
1023
1024 static enum print_line_t trace_ctxwake_bin(struct trace_iterator *iter,
1025 int flags, struct trace_event *event)
1026 {
1027 struct ctx_switch_entry *field;
1028 struct trace_seq *s = &iter->seq;
1029
1030 trace_assign_type(field, iter->ent);
1031
1032 SEQ_PUT_FIELD(s, field->prev_pid);
1033 SEQ_PUT_FIELD(s, field->prev_prio);
1034 SEQ_PUT_FIELD(s, field->prev_state);
1035 SEQ_PUT_FIELD(s, field->next_cpu);
1036 SEQ_PUT_FIELD(s, field->next_pid);
1037 SEQ_PUT_FIELD(s, field->next_prio);
1038 SEQ_PUT_FIELD(s, field->next_state);
1039
1040 return trace_handle_return(s);
1041 }
1042
1043 static struct trace_event_functions trace_ctx_funcs = {
1044 .trace = trace_ctx_print,
1045 .raw = trace_ctx_raw,
1046 .hex = trace_ctx_hex,
1047 .binary = trace_ctxwake_bin,
1048 };
1049
1050 static struct trace_event trace_ctx_event = {
1051 .type = TRACE_CTX,
1052 .funcs = &trace_ctx_funcs,
1053 };
1054
1055 static struct trace_event_functions trace_wake_funcs = {
1056 .trace = trace_wake_print,
1057 .raw = trace_wake_raw,
1058 .hex = trace_wake_hex,
1059 .binary = trace_ctxwake_bin,
1060 };
1061
1062 static struct trace_event trace_wake_event = {
1063 .type = TRACE_WAKE,
1064 .funcs = &trace_wake_funcs,
1065 };
1066
1067 /* TRACE_STACK */
1068
1069 static enum print_line_t trace_stack_print(struct trace_iterator *iter,
1070 int flags, struct trace_event *event)
1071 {
1072 struct stack_entry *field;
1073 struct trace_seq *s = &iter->seq;
1074 unsigned long *p;
1075 unsigned long *end;
1076
1077 trace_assign_type(field, iter->ent);
1078 end = (unsigned long *)((long)iter->ent + iter->ent_size);
1079
1080 trace_seq_puts(s, "<stack trace>\n");
1081
1082 for (p = field->caller; p && *p != ULONG_MAX && p < end; p++) {
1083
1084 if (trace_seq_has_overflowed(s))
1085 break;
1086
1087 trace_seq_puts(s, " => ");
1088 seq_print_ip_sym(s, *p, flags);
1089 trace_seq_putc(s, '\n');
1090 }
1091
1092 return trace_handle_return(s);
1093 }
1094
1095 static struct trace_event_functions trace_stack_funcs = {
1096 .trace = trace_stack_print,
1097 };
1098
1099 static struct trace_event trace_stack_event = {
1100 .type = TRACE_STACK,
1101 .funcs = &trace_stack_funcs,
1102 };
1103
1104 /* TRACE_USER_STACK */
1105 static enum print_line_t trace_user_stack_print(struct trace_iterator *iter,
1106 int flags, struct trace_event *event)
1107 {
1108 struct trace_array *tr = iter->tr;
1109 struct userstack_entry *field;
1110 struct trace_seq *s = &iter->seq;
1111 struct mm_struct *mm = NULL;
1112 unsigned int i;
1113
1114 trace_assign_type(field, iter->ent);
1115
1116 trace_seq_puts(s, "<user stack trace>\n");
1117
1118 if (tr->trace_flags & TRACE_ITER_SYM_USEROBJ) {
1119 struct task_struct *task;
1120 /*
1121 * we do the lookup on the thread group leader,
1122 * since individual threads might have already quit!
1123 */
1124 rcu_read_lock();
1125 task = find_task_by_vpid(field->tgid);
1126 if (task)
1127 mm = get_task_mm(task);
1128 rcu_read_unlock();
1129 }
1130
1131 for (i = 0; i < FTRACE_STACK_ENTRIES; i++) {
1132 unsigned long ip = field->caller[i];
1133
1134 if (ip == ULONG_MAX || trace_seq_has_overflowed(s))
1135 break;
1136
1137 trace_seq_puts(s, " => ");
1138
1139 if (!ip) {
1140 trace_seq_puts(s, "??");
1141 trace_seq_putc(s, '\n');
1142 continue;
1143 }
1144
1145 seq_print_user_ip(s, mm, ip, flags);
1146 trace_seq_putc(s, '\n');
1147 }
1148
1149 if (mm)
1150 mmput(mm);
1151
1152 return trace_handle_return(s);
1153 }
1154
1155 static struct trace_event_functions trace_user_stack_funcs = {
1156 .trace = trace_user_stack_print,
1157 };
1158
1159 static struct trace_event trace_user_stack_event = {
1160 .type = TRACE_USER_STACK,
1161 .funcs = &trace_user_stack_funcs,
1162 };
1163
1164 /* TRACE_HWLAT */
1165 static enum print_line_t
1166 trace_hwlat_print(struct trace_iterator *iter, int flags,
1167 struct trace_event *event)
1168 {
1169 struct trace_entry *entry = iter->ent;
1170 struct trace_seq *s = &iter->seq;
1171 struct hwlat_entry *field;
1172
1173 trace_assign_type(field, entry);
1174
1175 trace_seq_printf(s, "#%-5u inner/outer(us): %4llu/%-5llu ts:%lld.%09ld",
1176 field->seqnum,
1177 field->duration,
1178 field->outer_duration,
1179 (long long)field->timestamp.tv_sec,
1180 field->timestamp.tv_nsec);
1181
1182 if (field->nmi_count) {
1183 /*
1184 * The generic sched_clock() is not NMI safe, thus
1185 * we only record the count and not the time.
1186 */
1187 if (!IS_ENABLED(CONFIG_GENERIC_SCHED_CLOCK))
1188 trace_seq_printf(s, " nmi-total:%llu",
1189 field->nmi_total_ts);
1190 trace_seq_printf(s, " nmi-count:%u",
1191 field->nmi_count);
1192 }
1193
1194 trace_seq_putc(s, '\n');
1195
1196 return trace_handle_return(s);
1197 }
1198
1199
1200 static enum print_line_t
1201 trace_hwlat_raw(struct trace_iterator *iter, int flags,
1202 struct trace_event *event)
1203 {
1204 struct hwlat_entry *field;
1205 struct trace_seq *s = &iter->seq;
1206
1207 trace_assign_type(field, iter->ent);
1208
1209 trace_seq_printf(s, "%llu %lld %lld %09ld %u\n",
1210 field->duration,
1211 field->outer_duration,
1212 (long long)field->timestamp.tv_sec,
1213 field->timestamp.tv_nsec,
1214 field->seqnum);
1215
1216 return trace_handle_return(s);
1217 }
1218
1219 static struct trace_event_functions trace_hwlat_funcs = {
1220 .trace = trace_hwlat_print,
1221 .raw = trace_hwlat_raw,
1222 };
1223
1224 static struct trace_event trace_hwlat_event = {
1225 .type = TRACE_HWLAT,
1226 .funcs = &trace_hwlat_funcs,
1227 };
1228
1229 /* TRACE_BPUTS */
1230 static enum print_line_t
1231 trace_bputs_print(struct trace_iterator *iter, int flags,
1232 struct trace_event *event)
1233 {
1234 struct trace_entry *entry = iter->ent;
1235 struct trace_seq *s = &iter->seq;
1236 struct bputs_entry *field;
1237
1238 trace_assign_type(field, entry);
1239
1240 seq_print_ip_sym(s, field->ip, flags);
1241 trace_seq_puts(s, ": ");
1242 trace_seq_puts(s, field->str);
1243
1244 return trace_handle_return(s);
1245 }
1246
1247
1248 static enum print_line_t
1249 trace_bputs_raw(struct trace_iterator *iter, int flags,
1250 struct trace_event *event)
1251 {
1252 struct bputs_entry *field;
1253 struct trace_seq *s = &iter->seq;
1254
1255 trace_assign_type(field, iter->ent);
1256
1257 trace_seq_printf(s, ": %lx : ", field->ip);
1258 trace_seq_puts(s, field->str);
1259
1260 return trace_handle_return(s);
1261 }
1262
1263 static struct trace_event_functions trace_bputs_funcs = {
1264 .trace = trace_bputs_print,
1265 .raw = trace_bputs_raw,
1266 };
1267
1268 static struct trace_event trace_bputs_event = {
1269 .type = TRACE_BPUTS,
1270 .funcs = &trace_bputs_funcs,
1271 };
1272
1273 /* TRACE_BPRINT */
1274 static enum print_line_t
1275 trace_bprint_print(struct trace_iterator *iter, int flags,
1276 struct trace_event *event)
1277 {
1278 struct trace_entry *entry = iter->ent;
1279 struct trace_seq *s = &iter->seq;
1280 struct bprint_entry *field;
1281
1282 trace_assign_type(field, entry);
1283
1284 seq_print_ip_sym(s, field->ip, flags);
1285 trace_seq_puts(s, ": ");
1286 trace_seq_bprintf(s, field->fmt, field->buf);
1287
1288 return trace_handle_return(s);
1289 }
1290
1291
1292 static enum print_line_t
1293 trace_bprint_raw(struct trace_iterator *iter, int flags,
1294 struct trace_event *event)
1295 {
1296 struct bprint_entry *field;
1297 struct trace_seq *s = &iter->seq;
1298
1299 trace_assign_type(field, iter->ent);
1300
1301 trace_seq_printf(s, ": %lx : ", field->ip);
1302 trace_seq_bprintf(s, field->fmt, field->buf);
1303
1304 return trace_handle_return(s);
1305 }
1306
1307 static struct trace_event_functions trace_bprint_funcs = {
1308 .trace = trace_bprint_print,
1309 .raw = trace_bprint_raw,
1310 };
1311
1312 static struct trace_event trace_bprint_event = {
1313 .type = TRACE_BPRINT,
1314 .funcs = &trace_bprint_funcs,
1315 };
1316
1317 /* TRACE_PRINT */
1318 static enum print_line_t trace_print_print(struct trace_iterator *iter,
1319 int flags, struct trace_event *event)
1320 {
1321 struct print_entry *field;
1322 struct trace_seq *s = &iter->seq;
1323
1324 trace_assign_type(field, iter->ent);
1325
1326 seq_print_ip_sym(s, field->ip, flags);
1327 trace_seq_printf(s, ": %s", field->buf);
1328
1329 return trace_handle_return(s);
1330 }
1331
1332 static enum print_line_t trace_print_raw(struct trace_iterator *iter, int flags,
1333 struct trace_event *event)
1334 {
1335 struct print_entry *field;
1336
1337 trace_assign_type(field, iter->ent);
1338
1339 trace_seq_printf(&iter->seq, "# %lx %s", field->ip, field->buf);
1340
1341 return trace_handle_return(&iter->seq);
1342 }
1343
1344 static struct trace_event_functions trace_print_funcs = {
1345 .trace = trace_print_print,
1346 .raw = trace_print_raw,
1347 };
1348
1349 static struct trace_event trace_print_event = {
1350 .type = TRACE_PRINT,
1351 .funcs = &trace_print_funcs,
1352 };
1353
1354 static enum print_line_t trace_raw_data(struct trace_iterator *iter, int flags,
1355 struct trace_event *event)
1356 {
1357 struct raw_data_entry *field;
1358 int i;
1359
1360 trace_assign_type(field, iter->ent);
1361
1362 trace_seq_printf(&iter->seq, "# %x buf:", field->id);
1363
1364 for (i = 0; i < iter->ent_size - offsetof(struct raw_data_entry, buf); i++)
1365 trace_seq_printf(&iter->seq, " %02x",
1366 (unsigned char)field->buf[i]);
1367
1368 trace_seq_putc(&iter->seq, '\n');
1369
1370 return trace_handle_return(&iter->seq);
1371 }
1372
1373 static struct trace_event_functions trace_raw_data_funcs = {
1374 .trace = trace_raw_data,
1375 .raw = trace_raw_data,
1376 };
1377
1378 static struct trace_event trace_raw_data_event = {
1379 .type = TRACE_RAW_DATA,
1380 .funcs = &trace_raw_data_funcs,
1381 };
1382
1383
1384 static struct trace_event *events[] __initdata = {
1385 &trace_fn_event,
1386 &trace_ctx_event,
1387 &trace_wake_event,
1388 &trace_stack_event,
1389 &trace_user_stack_event,
1390 &trace_bputs_event,
1391 &trace_bprint_event,
1392 &trace_print_event,
1393 &trace_hwlat_event,
1394 &trace_raw_data_event,
1395 NULL
1396 };
1397
1398 __init static int init_events(void)
1399 {
1400 struct trace_event *event;
1401 int i, ret;
1402
1403 for (i = 0; events[i]; i++) {
1404 event = events[i];
1405
1406 ret = register_trace_event(event);
1407 if (!ret) {
1408 printk(KERN_WARNING "event %d failed to register\n",
1409 event->type);
1410 WARN_ON_ONCE(1);
1411 }
1412 }
1413
1414 return 0;
1415 }
1416 early_initcall(init_events);
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