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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/kprobes.h>
12#include <linux/sched/clock.h>
13#include <linux/sched/mm.h>
14#include <linux/idr.h>
15
16#include "trace_output.h"
17
18/* must be a power of 2 */
19#define EVENT_HASHSIZE 128
20
21DECLARE_RWSEM(trace_event_sem);
22
23static struct hlist_head event_hash[EVENT_HASHSIZE] __read_mostly;
24
25enum 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
38enum 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
51enum 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
64const char *
65trace_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}
100EXPORT_SYMBOL(trace_print_flags_seq);
101
102const char *
103trace_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}
125EXPORT_SYMBOL(trace_print_symbols_seq);
126
127#if BITS_PER_LONG == 32
128const char *
129trace_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}
164EXPORT_SYMBOL(trace_print_flags_seq_u64);
165
166const char *
167trace_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}
189EXPORT_SYMBOL(trace_print_symbols_seq_u64);
190#endif
191
192const char *
193trace_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}
203EXPORT_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 */
216const char *
217trace_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 const char *fmt = concatenate ? "%*phN" : "%*ph";
223
224 for (i = 0; i < buf_len; i += 16)
225 trace_seq_printf(p, fmt, min(buf_len - i, 16), &buf[i]);
226 trace_seq_putc(p, 0);
227
228 return ret;
229}
230EXPORT_SYMBOL(trace_print_hex_seq);
231
232const char *
233trace_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}
275EXPORT_SYMBOL(trace_print_array_seq);
276
277const char *
278trace_print_hex_dump_seq(struct trace_seq *p, const char *prefix_str,
279 int prefix_type, int rowsize, int groupsize,
280 const void *buf, size_t len, bool ascii)
281{
282 const char *ret = trace_seq_buffer_ptr(p);
283
284 trace_seq_putc(p, '\n');
285 trace_seq_hex_dump(p, prefix_str, prefix_type,
286 rowsize, groupsize, buf, len, ascii);
287 trace_seq_putc(p, 0);
288 return ret;
289}
290EXPORT_SYMBOL(trace_print_hex_dump_seq);
291
292int trace_raw_output_prep(struct trace_iterator *iter,
293 struct trace_event *trace_event)
294{
295 struct trace_event_call *event;
296 struct trace_seq *s = &iter->seq;
297 struct trace_seq *p = &iter->tmp_seq;
298 struct trace_entry *entry;
299
300 event = container_of(trace_event, struct trace_event_call, event);
301 entry = iter->ent;
302
303 if (entry->type != event->event.type) {
304 WARN_ON_ONCE(1);
305 return TRACE_TYPE_UNHANDLED;
306 }
307
308 trace_seq_init(p);
309 trace_seq_printf(s, "%s: ", trace_event_name(event));
310
311 return trace_handle_return(s);
312}
313EXPORT_SYMBOL(trace_raw_output_prep);
314
315void trace_event_printf(struct trace_iterator *iter, const char *fmt, ...)
316{
317 va_list ap;
318
319 va_start(ap, fmt);
320 trace_check_vprintf(iter, trace_event_format(iter, fmt), ap);
321 va_end(ap);
322}
323EXPORT_SYMBOL(trace_event_printf);
324
325static __printf(3, 0)
326int trace_output_raw(struct trace_iterator *iter, char *name,
327 char *fmt, va_list ap)
328{
329 struct trace_seq *s = &iter->seq;
330
331 trace_seq_printf(s, "%s: ", name);
332 trace_seq_vprintf(s, trace_event_format(iter, fmt), ap);
333
334 return trace_handle_return(s);
335}
336
337int trace_output_call(struct trace_iterator *iter, char *name, char *fmt, ...)
338{
339 va_list ap;
340 int ret;
341
342 va_start(ap, fmt);
343 ret = trace_output_raw(iter, name, fmt, ap);
344 va_end(ap);
345
346 return ret;
347}
348EXPORT_SYMBOL_GPL(trace_output_call);
349
350static inline const char *kretprobed(const char *name, unsigned long addr)
351{
352 if (is_kretprobe_trampoline(addr))
353 return "[unknown/kretprobe'd]";
354 return name;
355}
356
357void
358trace_seq_print_sym(struct trace_seq *s, unsigned long address, bool offset)
359{
360#ifdef CONFIG_KALLSYMS
361 char str[KSYM_SYMBOL_LEN];
362 const char *name;
363
364 if (offset)
365 sprint_symbol(str, address);
366 else
367 kallsyms_lookup(address, NULL, NULL, NULL, str);
368 name = kretprobed(str, address);
369
370 if (name && strlen(name)) {
371 trace_seq_puts(s, name);
372 return;
373 }
374#endif
375 trace_seq_printf(s, "0x%08lx", address);
376}
377
378#ifndef CONFIG_64BIT
379# define IP_FMT "%08lx"
380#else
381# define IP_FMT "%016lx"
382#endif
383
384static int seq_print_user_ip(struct trace_seq *s, struct mm_struct *mm,
385 unsigned long ip, unsigned long sym_flags)
386{
387 struct file *file = NULL;
388 unsigned long vmstart = 0;
389 int ret = 1;
390
391 if (s->full)
392 return 0;
393
394 if (mm) {
395 const struct vm_area_struct *vma;
396
397 mmap_read_lock(mm);
398 vma = find_vma(mm, ip);
399 if (vma) {
400 file = vma->vm_file;
401 vmstart = vma->vm_start;
402 }
403 if (file) {
404 ret = trace_seq_path(s, &file->f_path);
405 if (ret)
406 trace_seq_printf(s, "[+0x%lx]",
407 ip - vmstart);
408 }
409 mmap_read_unlock(mm);
410 }
411 if (ret && ((sym_flags & TRACE_ITER_SYM_ADDR) || !file))
412 trace_seq_printf(s, " <" IP_FMT ">", ip);
413 return !trace_seq_has_overflowed(s);
414}
415
416int
417seq_print_ip_sym(struct trace_seq *s, unsigned long ip, unsigned long sym_flags)
418{
419 if (!ip) {
420 trace_seq_putc(s, '0');
421 goto out;
422 }
423
424 trace_seq_print_sym(s, ip, sym_flags & TRACE_ITER_SYM_OFFSET);
425
426 if (sym_flags & TRACE_ITER_SYM_ADDR)
427 trace_seq_printf(s, " <" IP_FMT ">", ip);
428
429 out:
430 return !trace_seq_has_overflowed(s);
431}
432
433/**
434 * trace_print_lat_fmt - print the irq, preempt and lockdep fields
435 * @s: trace seq struct to write to
436 * @entry: The trace entry field from the ring buffer
437 *
438 * Prints the generic fields of irqs off, in hard or softirq, preempt
439 * count.
440 */
441int trace_print_lat_fmt(struct trace_seq *s, struct trace_entry *entry)
442{
443 char hardsoft_irq;
444 char need_resched;
445 char irqs_off;
446 int hardirq;
447 int softirq;
448 int bh_off;
449 int nmi;
450
451 nmi = entry->flags & TRACE_FLAG_NMI;
452 hardirq = entry->flags & TRACE_FLAG_HARDIRQ;
453 softirq = entry->flags & TRACE_FLAG_SOFTIRQ;
454 bh_off = entry->flags & TRACE_FLAG_BH_OFF;
455
456 irqs_off =
457 (entry->flags & TRACE_FLAG_IRQS_OFF && bh_off) ? 'D' :
458 (entry->flags & TRACE_FLAG_IRQS_OFF) ? 'd' :
459 bh_off ? 'b' :
460 (entry->flags & TRACE_FLAG_IRQS_NOSUPPORT) ? 'X' :
461 '.';
462
463 switch (entry->flags & (TRACE_FLAG_NEED_RESCHED |
464 TRACE_FLAG_PREEMPT_RESCHED)) {
465 case TRACE_FLAG_NEED_RESCHED | TRACE_FLAG_PREEMPT_RESCHED:
466 need_resched = 'N';
467 break;
468 case TRACE_FLAG_NEED_RESCHED:
469 need_resched = 'n';
470 break;
471 case TRACE_FLAG_PREEMPT_RESCHED:
472 need_resched = 'p';
473 break;
474 default:
475 need_resched = '.';
476 break;
477 }
478
479 hardsoft_irq =
480 (nmi && hardirq) ? 'Z' :
481 nmi ? 'z' :
482 (hardirq && softirq) ? 'H' :
483 hardirq ? 'h' :
484 softirq ? 's' :
485 '.' ;
486
487 trace_seq_printf(s, "%c%c%c",
488 irqs_off, need_resched, hardsoft_irq);
489
490 if (entry->preempt_count & 0xf)
491 trace_seq_printf(s, "%x", entry->preempt_count & 0xf);
492 else
493 trace_seq_putc(s, '.');
494
495 if (entry->preempt_count & 0xf0)
496 trace_seq_printf(s, "%x", entry->preempt_count >> 4);
497 else
498 trace_seq_putc(s, '.');
499
500 return !trace_seq_has_overflowed(s);
501}
502
503static int
504lat_print_generic(struct trace_seq *s, struct trace_entry *entry, int cpu)
505{
506 char comm[TASK_COMM_LEN];
507
508 trace_find_cmdline(entry->pid, comm);
509
510 trace_seq_printf(s, "%8.8s-%-7d %3d",
511 comm, entry->pid, cpu);
512
513 return trace_print_lat_fmt(s, entry);
514}
515
516#undef MARK
517#define MARK(v, s) {.val = v, .sym = s}
518/* trace overhead mark */
519static const struct trace_mark {
520 unsigned long long val; /* unit: nsec */
521 char sym;
522} mark[] = {
523 MARK(1000000000ULL , '$'), /* 1 sec */
524 MARK(100000000ULL , '@'), /* 100 msec */
525 MARK(10000000ULL , '*'), /* 10 msec */
526 MARK(1000000ULL , '#'), /* 1000 usecs */
527 MARK(100000ULL , '!'), /* 100 usecs */
528 MARK(10000ULL , '+'), /* 10 usecs */
529};
530#undef MARK
531
532char trace_find_mark(unsigned long long d)
533{
534 int i;
535 int size = ARRAY_SIZE(mark);
536
537 for (i = 0; i < size; i++) {
538 if (d > mark[i].val)
539 break;
540 }
541
542 return (i == size) ? ' ' : mark[i].sym;
543}
544
545static int
546lat_print_timestamp(struct trace_iterator *iter, u64 next_ts)
547{
548 struct trace_array *tr = iter->tr;
549 unsigned long verbose = tr->trace_flags & TRACE_ITER_VERBOSE;
550 unsigned long in_ns = iter->iter_flags & TRACE_FILE_TIME_IN_NS;
551 unsigned long long abs_ts = iter->ts - iter->array_buffer->time_start;
552 unsigned long long rel_ts = next_ts - iter->ts;
553 struct trace_seq *s = &iter->seq;
554
555 if (in_ns) {
556 abs_ts = ns2usecs(abs_ts);
557 rel_ts = ns2usecs(rel_ts);
558 }
559
560 if (verbose && in_ns) {
561 unsigned long abs_usec = do_div(abs_ts, USEC_PER_MSEC);
562 unsigned long abs_msec = (unsigned long)abs_ts;
563 unsigned long rel_usec = do_div(rel_ts, USEC_PER_MSEC);
564 unsigned long rel_msec = (unsigned long)rel_ts;
565
566 trace_seq_printf(
567 s, "[%08llx] %ld.%03ldms (+%ld.%03ldms): ",
568 ns2usecs(iter->ts),
569 abs_msec, abs_usec,
570 rel_msec, rel_usec);
571
572 } else if (verbose && !in_ns) {
573 trace_seq_printf(
574 s, "[%016llx] %lld (+%lld): ",
575 iter->ts, abs_ts, rel_ts);
576
577 } else if (!verbose && in_ns) {
578 trace_seq_printf(
579 s, " %4lldus%c: ",
580 abs_ts,
581 trace_find_mark(rel_ts * NSEC_PER_USEC));
582
583 } else { /* !verbose && !in_ns */
584 trace_seq_printf(s, " %4lld: ", abs_ts);
585 }
586
587 return !trace_seq_has_overflowed(s);
588}
589
590static void trace_print_time(struct trace_seq *s, struct trace_iterator *iter,
591 unsigned long long ts)
592{
593 unsigned long secs, usec_rem;
594 unsigned long long t;
595
596 if (iter->iter_flags & TRACE_FILE_TIME_IN_NS) {
597 t = ns2usecs(ts);
598 usec_rem = do_div(t, USEC_PER_SEC);
599 secs = (unsigned long)t;
600 trace_seq_printf(s, " %5lu.%06lu", secs, usec_rem);
601 } else
602 trace_seq_printf(s, " %12llu", ts);
603}
604
605int trace_print_context(struct trace_iterator *iter)
606{
607 struct trace_array *tr = iter->tr;
608 struct trace_seq *s = &iter->seq;
609 struct trace_entry *entry = iter->ent;
610 char comm[TASK_COMM_LEN];
611
612 trace_find_cmdline(entry->pid, comm);
613
614 trace_seq_printf(s, "%16s-%-7d ", comm, entry->pid);
615
616 if (tr->trace_flags & TRACE_ITER_RECORD_TGID) {
617 unsigned int tgid = trace_find_tgid(entry->pid);
618
619 if (!tgid)
620 trace_seq_printf(s, "(-------) ");
621 else
622 trace_seq_printf(s, "(%7d) ", tgid);
623 }
624
625 trace_seq_printf(s, "[%03d] ", iter->cpu);
626
627 if (tr->trace_flags & TRACE_ITER_IRQ_INFO)
628 trace_print_lat_fmt(s, entry);
629
630 trace_print_time(s, iter, iter->ts);
631 trace_seq_puts(s, ": ");
632
633 return !trace_seq_has_overflowed(s);
634}
635
636int trace_print_lat_context(struct trace_iterator *iter)
637{
638 struct trace_entry *entry, *next_entry;
639 struct trace_array *tr = iter->tr;
640 struct trace_seq *s = &iter->seq;
641 unsigned long verbose = (tr->trace_flags & TRACE_ITER_VERBOSE);
642 u64 next_ts;
643
644 next_entry = trace_find_next_entry(iter, NULL, &next_ts);
645 if (!next_entry)
646 next_ts = iter->ts;
647
648 /* trace_find_next_entry() may change iter->ent */
649 entry = iter->ent;
650
651 if (verbose) {
652 char comm[TASK_COMM_LEN];
653
654 trace_find_cmdline(entry->pid, comm);
655
656 trace_seq_printf(
657 s, "%16s %7d %3d %d %08x %08lx ",
658 comm, entry->pid, iter->cpu, entry->flags,
659 entry->preempt_count & 0xf, iter->idx);
660 } else {
661 lat_print_generic(s, entry, iter->cpu);
662 }
663
664 lat_print_timestamp(iter, next_ts);
665
666 return !trace_seq_has_overflowed(s);
667}
668
669/**
670 * ftrace_find_event - find a registered event
671 * @type: the type of event to look for
672 *
673 * Returns an event of type @type otherwise NULL
674 * Called with trace_event_read_lock() held.
675 */
676struct trace_event *ftrace_find_event(int type)
677{
678 struct trace_event *event;
679 unsigned key;
680
681 key = type & (EVENT_HASHSIZE - 1);
682
683 hlist_for_each_entry(event, &event_hash[key], node) {
684 if (event->type == type)
685 return event;
686 }
687
688 return NULL;
689}
690
691static DEFINE_IDA(trace_event_ida);
692
693static void free_trace_event_type(int type)
694{
695 if (type >= __TRACE_LAST_TYPE)
696 ida_free(&trace_event_ida, type);
697}
698
699static int alloc_trace_event_type(void)
700{
701 int next;
702
703 /* Skip static defined type numbers */
704 next = ida_alloc_range(&trace_event_ida, __TRACE_LAST_TYPE,
705 TRACE_EVENT_TYPE_MAX, GFP_KERNEL);
706 if (next < 0)
707 return 0;
708 return next;
709}
710
711void trace_event_read_lock(void)
712{
713 down_read(&trace_event_sem);
714}
715
716void trace_event_read_unlock(void)
717{
718 up_read(&trace_event_sem);
719}
720
721/**
722 * register_trace_event - register output for an event type
723 * @event: the event type to register
724 *
725 * Event types are stored in a hash and this hash is used to
726 * find a way to print an event. If the @event->type is set
727 * then it will use that type, otherwise it will assign a
728 * type to use.
729 *
730 * If you assign your own type, please make sure it is added
731 * to the trace_type enum in trace.h, to avoid collisions
732 * with the dynamic types.
733 *
734 * Returns the event type number or zero on error.
735 */
736int register_trace_event(struct trace_event *event)
737{
738 unsigned key;
739 int ret = 0;
740
741 down_write(&trace_event_sem);
742
743 if (WARN_ON(!event))
744 goto out;
745
746 if (WARN_ON(!event->funcs))
747 goto out;
748
749 if (!event->type) {
750 event->type = alloc_trace_event_type();
751 if (!event->type)
752 goto out;
753 } else if (WARN(event->type > __TRACE_LAST_TYPE,
754 "Need to add type to trace.h")) {
755 goto out;
756 } else {
757 /* Is this event already used */
758 if (ftrace_find_event(event->type))
759 goto out;
760 }
761
762 if (event->funcs->trace == NULL)
763 event->funcs->trace = trace_nop_print;
764 if (event->funcs->raw == NULL)
765 event->funcs->raw = trace_nop_print;
766 if (event->funcs->hex == NULL)
767 event->funcs->hex = trace_nop_print;
768 if (event->funcs->binary == NULL)
769 event->funcs->binary = trace_nop_print;
770
771 key = event->type & (EVENT_HASHSIZE - 1);
772
773 hlist_add_head(&event->node, &event_hash[key]);
774
775 ret = event->type;
776 out:
777 up_write(&trace_event_sem);
778
779 return ret;
780}
781EXPORT_SYMBOL_GPL(register_trace_event);
782
783/*
784 * Used by module code with the trace_event_sem held for write.
785 */
786int __unregister_trace_event(struct trace_event *event)
787{
788 hlist_del(&event->node);
789 free_trace_event_type(event->type);
790 return 0;
791}
792
793/**
794 * unregister_trace_event - remove a no longer used event
795 * @event: the event to remove
796 */
797int unregister_trace_event(struct trace_event *event)
798{
799 down_write(&trace_event_sem);
800 __unregister_trace_event(event);
801 up_write(&trace_event_sem);
802
803 return 0;
804}
805EXPORT_SYMBOL_GPL(unregister_trace_event);
806
807/*
808 * Standard events
809 */
810
811enum print_line_t trace_nop_print(struct trace_iterator *iter, int flags,
812 struct trace_event *event)
813{
814 trace_seq_printf(&iter->seq, "type: %d\n", iter->ent->type);
815
816 return trace_handle_return(&iter->seq);
817}
818
819static void print_fn_trace(struct trace_seq *s, unsigned long ip,
820 unsigned long parent_ip, int flags)
821{
822 seq_print_ip_sym(s, ip, flags);
823
824 if ((flags & TRACE_ITER_PRINT_PARENT) && parent_ip) {
825 trace_seq_puts(s, " <-");
826 seq_print_ip_sym(s, parent_ip, flags);
827 }
828}
829
830/* TRACE_FN */
831static enum print_line_t trace_fn_trace(struct trace_iterator *iter, int flags,
832 struct trace_event *event)
833{
834 struct ftrace_entry *field;
835 struct trace_seq *s = &iter->seq;
836
837 trace_assign_type(field, iter->ent);
838
839 print_fn_trace(s, field->ip, field->parent_ip, flags);
840 trace_seq_putc(s, '\n');
841
842 return trace_handle_return(s);
843}
844
845static enum print_line_t trace_fn_raw(struct trace_iterator *iter, int flags,
846 struct trace_event *event)
847{
848 struct ftrace_entry *field;
849
850 trace_assign_type(field, iter->ent);
851
852 trace_seq_printf(&iter->seq, "%lx %lx\n",
853 field->ip,
854 field->parent_ip);
855
856 return trace_handle_return(&iter->seq);
857}
858
859static enum print_line_t trace_fn_hex(struct trace_iterator *iter, int flags,
860 struct trace_event *event)
861{
862 struct ftrace_entry *field;
863 struct trace_seq *s = &iter->seq;
864
865 trace_assign_type(field, iter->ent);
866
867 SEQ_PUT_HEX_FIELD(s, field->ip);
868 SEQ_PUT_HEX_FIELD(s, field->parent_ip);
869
870 return trace_handle_return(s);
871}
872
873static enum print_line_t trace_fn_bin(struct trace_iterator *iter, int flags,
874 struct trace_event *event)
875{
876 struct ftrace_entry *field;
877 struct trace_seq *s = &iter->seq;
878
879 trace_assign_type(field, iter->ent);
880
881 SEQ_PUT_FIELD(s, field->ip);
882 SEQ_PUT_FIELD(s, field->parent_ip);
883
884 return trace_handle_return(s);
885}
886
887static struct trace_event_functions trace_fn_funcs = {
888 .trace = trace_fn_trace,
889 .raw = trace_fn_raw,
890 .hex = trace_fn_hex,
891 .binary = trace_fn_bin,
892};
893
894static struct trace_event trace_fn_event = {
895 .type = TRACE_FN,
896 .funcs = &trace_fn_funcs,
897};
898
899/* TRACE_CTX an TRACE_WAKE */
900static enum print_line_t trace_ctxwake_print(struct trace_iterator *iter,
901 char *delim)
902{
903 struct ctx_switch_entry *field;
904 char comm[TASK_COMM_LEN];
905 int S, T;
906
907
908 trace_assign_type(field, iter->ent);
909
910 T = task_index_to_char(field->next_state);
911 S = task_index_to_char(field->prev_state);
912 trace_find_cmdline(field->next_pid, comm);
913 trace_seq_printf(&iter->seq,
914 " %7d:%3d:%c %s [%03d] %7d:%3d:%c %s\n",
915 field->prev_pid,
916 field->prev_prio,
917 S, delim,
918 field->next_cpu,
919 field->next_pid,
920 field->next_prio,
921 T, comm);
922
923 return trace_handle_return(&iter->seq);
924}
925
926static enum print_line_t trace_ctx_print(struct trace_iterator *iter, int flags,
927 struct trace_event *event)
928{
929 return trace_ctxwake_print(iter, "==>");
930}
931
932static enum print_line_t trace_wake_print(struct trace_iterator *iter,
933 int flags, struct trace_event *event)
934{
935 return trace_ctxwake_print(iter, " +");
936}
937
938static int trace_ctxwake_raw(struct trace_iterator *iter, char S)
939{
940 struct ctx_switch_entry *field;
941 int T;
942
943 trace_assign_type(field, iter->ent);
944
945 if (!S)
946 S = task_index_to_char(field->prev_state);
947 T = task_index_to_char(field->next_state);
948 trace_seq_printf(&iter->seq, "%d %d %c %d %d %d %c\n",
949 field->prev_pid,
950 field->prev_prio,
951 S,
952 field->next_cpu,
953 field->next_pid,
954 field->next_prio,
955 T);
956
957 return trace_handle_return(&iter->seq);
958}
959
960static enum print_line_t trace_ctx_raw(struct trace_iterator *iter, int flags,
961 struct trace_event *event)
962{
963 return trace_ctxwake_raw(iter, 0);
964}
965
966static enum print_line_t trace_wake_raw(struct trace_iterator *iter, int flags,
967 struct trace_event *event)
968{
969 return trace_ctxwake_raw(iter, '+');
970}
971
972
973static int trace_ctxwake_hex(struct trace_iterator *iter, char S)
974{
975 struct ctx_switch_entry *field;
976 struct trace_seq *s = &iter->seq;
977 int T;
978
979 trace_assign_type(field, iter->ent);
980
981 if (!S)
982 S = task_index_to_char(field->prev_state);
983 T = task_index_to_char(field->next_state);
984
985 SEQ_PUT_HEX_FIELD(s, field->prev_pid);
986 SEQ_PUT_HEX_FIELD(s, field->prev_prio);
987 SEQ_PUT_HEX_FIELD(s, S);
988 SEQ_PUT_HEX_FIELD(s, field->next_cpu);
989 SEQ_PUT_HEX_FIELD(s, field->next_pid);
990 SEQ_PUT_HEX_FIELD(s, field->next_prio);
991 SEQ_PUT_HEX_FIELD(s, T);
992
993 return trace_handle_return(s);
994}
995
996static enum print_line_t trace_ctx_hex(struct trace_iterator *iter, int flags,
997 struct trace_event *event)
998{
999 return trace_ctxwake_hex(iter, 0);
1000}
1001
1002static enum print_line_t trace_wake_hex(struct trace_iterator *iter, int flags,
1003 struct trace_event *event)
1004{
1005 return trace_ctxwake_hex(iter, '+');
1006}
1007
1008static enum print_line_t trace_ctxwake_bin(struct trace_iterator *iter,
1009 int flags, struct trace_event *event)
1010{
1011 struct ctx_switch_entry *field;
1012 struct trace_seq *s = &iter->seq;
1013
1014 trace_assign_type(field, iter->ent);
1015
1016 SEQ_PUT_FIELD(s, field->prev_pid);
1017 SEQ_PUT_FIELD(s, field->prev_prio);
1018 SEQ_PUT_FIELD(s, field->prev_state);
1019 SEQ_PUT_FIELD(s, field->next_cpu);
1020 SEQ_PUT_FIELD(s, field->next_pid);
1021 SEQ_PUT_FIELD(s, field->next_prio);
1022 SEQ_PUT_FIELD(s, field->next_state);
1023
1024 return trace_handle_return(s);
1025}
1026
1027static struct trace_event_functions trace_ctx_funcs = {
1028 .trace = trace_ctx_print,
1029 .raw = trace_ctx_raw,
1030 .hex = trace_ctx_hex,
1031 .binary = trace_ctxwake_bin,
1032};
1033
1034static struct trace_event trace_ctx_event = {
1035 .type = TRACE_CTX,
1036 .funcs = &trace_ctx_funcs,
1037};
1038
1039static struct trace_event_functions trace_wake_funcs = {
1040 .trace = trace_wake_print,
1041 .raw = trace_wake_raw,
1042 .hex = trace_wake_hex,
1043 .binary = trace_ctxwake_bin,
1044};
1045
1046static struct trace_event trace_wake_event = {
1047 .type = TRACE_WAKE,
1048 .funcs = &trace_wake_funcs,
1049};
1050
1051/* TRACE_STACK */
1052
1053static enum print_line_t trace_stack_print(struct trace_iterator *iter,
1054 int flags, struct trace_event *event)
1055{
1056 struct stack_entry *field;
1057 struct trace_seq *s = &iter->seq;
1058 unsigned long *p;
1059 unsigned long *end;
1060
1061 trace_assign_type(field, iter->ent);
1062 end = (unsigned long *)((long)iter->ent + iter->ent_size);
1063
1064 trace_seq_puts(s, "<stack trace>\n");
1065
1066 for (p = field->caller; p && p < end && *p != ULONG_MAX; p++) {
1067
1068 if (trace_seq_has_overflowed(s))
1069 break;
1070
1071 trace_seq_puts(s, " => ");
1072 seq_print_ip_sym(s, *p, flags);
1073 trace_seq_putc(s, '\n');
1074 }
1075
1076 return trace_handle_return(s);
1077}
1078
1079static struct trace_event_functions trace_stack_funcs = {
1080 .trace = trace_stack_print,
1081};
1082
1083static struct trace_event trace_stack_event = {
1084 .type = TRACE_STACK,
1085 .funcs = &trace_stack_funcs,
1086};
1087
1088/* TRACE_USER_STACK */
1089static enum print_line_t trace_user_stack_print(struct trace_iterator *iter,
1090 int flags, struct trace_event *event)
1091{
1092 struct trace_array *tr = iter->tr;
1093 struct userstack_entry *field;
1094 struct trace_seq *s = &iter->seq;
1095 struct mm_struct *mm = NULL;
1096 unsigned int i;
1097
1098 trace_assign_type(field, iter->ent);
1099
1100 trace_seq_puts(s, "<user stack trace>\n");
1101
1102 if (tr->trace_flags & TRACE_ITER_SYM_USEROBJ) {
1103 struct task_struct *task;
1104 /*
1105 * we do the lookup on the thread group leader,
1106 * since individual threads might have already quit!
1107 */
1108 rcu_read_lock();
1109 task = find_task_by_vpid(field->tgid);
1110 if (task)
1111 mm = get_task_mm(task);
1112 rcu_read_unlock();
1113 }
1114
1115 for (i = 0; i < FTRACE_STACK_ENTRIES; i++) {
1116 unsigned long ip = field->caller[i];
1117
1118 if (!ip || trace_seq_has_overflowed(s))
1119 break;
1120
1121 trace_seq_puts(s, " => ");
1122 seq_print_user_ip(s, mm, ip, flags);
1123 trace_seq_putc(s, '\n');
1124 }
1125
1126 if (mm)
1127 mmput(mm);
1128
1129 return trace_handle_return(s);
1130}
1131
1132static struct trace_event_functions trace_user_stack_funcs = {
1133 .trace = trace_user_stack_print,
1134};
1135
1136static struct trace_event trace_user_stack_event = {
1137 .type = TRACE_USER_STACK,
1138 .funcs = &trace_user_stack_funcs,
1139};
1140
1141/* TRACE_HWLAT */
1142static enum print_line_t
1143trace_hwlat_print(struct trace_iterator *iter, int flags,
1144 struct trace_event *event)
1145{
1146 struct trace_entry *entry = iter->ent;
1147 struct trace_seq *s = &iter->seq;
1148 struct hwlat_entry *field;
1149
1150 trace_assign_type(field, entry);
1151
1152 trace_seq_printf(s, "#%-5u inner/outer(us): %4llu/%-5llu ts:%lld.%09ld count:%d",
1153 field->seqnum,
1154 field->duration,
1155 field->outer_duration,
1156 (long long)field->timestamp.tv_sec,
1157 field->timestamp.tv_nsec, field->count);
1158
1159 if (field->nmi_count) {
1160 /*
1161 * The generic sched_clock() is not NMI safe, thus
1162 * we only record the count and not the time.
1163 */
1164 if (!IS_ENABLED(CONFIG_GENERIC_SCHED_CLOCK))
1165 trace_seq_printf(s, " nmi-total:%llu",
1166 field->nmi_total_ts);
1167 trace_seq_printf(s, " nmi-count:%u",
1168 field->nmi_count);
1169 }
1170
1171 trace_seq_putc(s, '\n');
1172
1173 return trace_handle_return(s);
1174}
1175
1176static enum print_line_t
1177trace_hwlat_raw(struct trace_iterator *iter, int flags,
1178 struct trace_event *event)
1179{
1180 struct hwlat_entry *field;
1181 struct trace_seq *s = &iter->seq;
1182
1183 trace_assign_type(field, iter->ent);
1184
1185 trace_seq_printf(s, "%llu %lld %lld %09ld %u\n",
1186 field->duration,
1187 field->outer_duration,
1188 (long long)field->timestamp.tv_sec,
1189 field->timestamp.tv_nsec,
1190 field->seqnum);
1191
1192 return trace_handle_return(s);
1193}
1194
1195static struct trace_event_functions trace_hwlat_funcs = {
1196 .trace = trace_hwlat_print,
1197 .raw = trace_hwlat_raw,
1198};
1199
1200static struct trace_event trace_hwlat_event = {
1201 .type = TRACE_HWLAT,
1202 .funcs = &trace_hwlat_funcs,
1203};
1204
1205/* TRACE_OSNOISE */
1206static enum print_line_t
1207trace_osnoise_print(struct trace_iterator *iter, int flags,
1208 struct trace_event *event)
1209{
1210 struct trace_entry *entry = iter->ent;
1211 struct trace_seq *s = &iter->seq;
1212 struct osnoise_entry *field;
1213 u64 ratio, ratio_dec;
1214 u64 net_runtime;
1215
1216 trace_assign_type(field, entry);
1217
1218 /*
1219 * compute the available % of cpu time.
1220 */
1221 net_runtime = field->runtime - field->noise;
1222 ratio = net_runtime * 10000000;
1223 do_div(ratio, field->runtime);
1224 ratio_dec = do_div(ratio, 100000);
1225
1226 trace_seq_printf(s, "%llu %10llu %3llu.%05llu %7llu",
1227 field->runtime,
1228 field->noise,
1229 ratio, ratio_dec,
1230 field->max_sample);
1231
1232 trace_seq_printf(s, " %6u", field->hw_count);
1233 trace_seq_printf(s, " %6u", field->nmi_count);
1234 trace_seq_printf(s, " %6u", field->irq_count);
1235 trace_seq_printf(s, " %6u", field->softirq_count);
1236 trace_seq_printf(s, " %6u", field->thread_count);
1237
1238 trace_seq_putc(s, '\n');
1239
1240 return trace_handle_return(s);
1241}
1242
1243static enum print_line_t
1244trace_osnoise_raw(struct trace_iterator *iter, int flags,
1245 struct trace_event *event)
1246{
1247 struct osnoise_entry *field;
1248 struct trace_seq *s = &iter->seq;
1249
1250 trace_assign_type(field, iter->ent);
1251
1252 trace_seq_printf(s, "%lld %llu %llu %u %u %u %u %u\n",
1253 field->runtime,
1254 field->noise,
1255 field->max_sample,
1256 field->hw_count,
1257 field->nmi_count,
1258 field->irq_count,
1259 field->softirq_count,
1260 field->thread_count);
1261
1262 return trace_handle_return(s);
1263}
1264
1265static struct trace_event_functions trace_osnoise_funcs = {
1266 .trace = trace_osnoise_print,
1267 .raw = trace_osnoise_raw,
1268};
1269
1270static struct trace_event trace_osnoise_event = {
1271 .type = TRACE_OSNOISE,
1272 .funcs = &trace_osnoise_funcs,
1273};
1274
1275/* TRACE_TIMERLAT */
1276static enum print_line_t
1277trace_timerlat_print(struct trace_iterator *iter, int flags,
1278 struct trace_event *event)
1279{
1280 struct trace_entry *entry = iter->ent;
1281 struct trace_seq *s = &iter->seq;
1282 struct timerlat_entry *field;
1283
1284 trace_assign_type(field, entry);
1285
1286 trace_seq_printf(s, "#%-5u context %6s timer_latency %9llu ns\n",
1287 field->seqnum,
1288 field->context ? "thread" : "irq",
1289 field->timer_latency);
1290
1291 return trace_handle_return(s);
1292}
1293
1294static enum print_line_t
1295trace_timerlat_raw(struct trace_iterator *iter, int flags,
1296 struct trace_event *event)
1297{
1298 struct timerlat_entry *field;
1299 struct trace_seq *s = &iter->seq;
1300
1301 trace_assign_type(field, iter->ent);
1302
1303 trace_seq_printf(s, "%u %d %llu\n",
1304 field->seqnum,
1305 field->context,
1306 field->timer_latency);
1307
1308 return trace_handle_return(s);
1309}
1310
1311static struct trace_event_functions trace_timerlat_funcs = {
1312 .trace = trace_timerlat_print,
1313 .raw = trace_timerlat_raw,
1314};
1315
1316static struct trace_event trace_timerlat_event = {
1317 .type = TRACE_TIMERLAT,
1318 .funcs = &trace_timerlat_funcs,
1319};
1320
1321/* TRACE_BPUTS */
1322static enum print_line_t
1323trace_bputs_print(struct trace_iterator *iter, int flags,
1324 struct trace_event *event)
1325{
1326 struct trace_entry *entry = iter->ent;
1327 struct trace_seq *s = &iter->seq;
1328 struct bputs_entry *field;
1329
1330 trace_assign_type(field, entry);
1331
1332 seq_print_ip_sym(s, field->ip, flags);
1333 trace_seq_puts(s, ": ");
1334 trace_seq_puts(s, field->str);
1335
1336 return trace_handle_return(s);
1337}
1338
1339
1340static enum print_line_t
1341trace_bputs_raw(struct trace_iterator *iter, int flags,
1342 struct trace_event *event)
1343{
1344 struct bputs_entry *field;
1345 struct trace_seq *s = &iter->seq;
1346
1347 trace_assign_type(field, iter->ent);
1348
1349 trace_seq_printf(s, ": %lx : ", field->ip);
1350 trace_seq_puts(s, field->str);
1351
1352 return trace_handle_return(s);
1353}
1354
1355static struct trace_event_functions trace_bputs_funcs = {
1356 .trace = trace_bputs_print,
1357 .raw = trace_bputs_raw,
1358};
1359
1360static struct trace_event trace_bputs_event = {
1361 .type = TRACE_BPUTS,
1362 .funcs = &trace_bputs_funcs,
1363};
1364
1365/* TRACE_BPRINT */
1366static enum print_line_t
1367trace_bprint_print(struct trace_iterator *iter, int flags,
1368 struct trace_event *event)
1369{
1370 struct trace_entry *entry = iter->ent;
1371 struct trace_seq *s = &iter->seq;
1372 struct bprint_entry *field;
1373
1374 trace_assign_type(field, entry);
1375
1376 seq_print_ip_sym(s, field->ip, flags);
1377 trace_seq_puts(s, ": ");
1378 trace_seq_bprintf(s, field->fmt, field->buf);
1379
1380 return trace_handle_return(s);
1381}
1382
1383
1384static enum print_line_t
1385trace_bprint_raw(struct trace_iterator *iter, int flags,
1386 struct trace_event *event)
1387{
1388 struct bprint_entry *field;
1389 struct trace_seq *s = &iter->seq;
1390
1391 trace_assign_type(field, iter->ent);
1392
1393 trace_seq_printf(s, ": %lx : ", field->ip);
1394 trace_seq_bprintf(s, field->fmt, field->buf);
1395
1396 return trace_handle_return(s);
1397}
1398
1399static struct trace_event_functions trace_bprint_funcs = {
1400 .trace = trace_bprint_print,
1401 .raw = trace_bprint_raw,
1402};
1403
1404static struct trace_event trace_bprint_event = {
1405 .type = TRACE_BPRINT,
1406 .funcs = &trace_bprint_funcs,
1407};
1408
1409/* TRACE_PRINT */
1410static enum print_line_t trace_print_print(struct trace_iterator *iter,
1411 int flags, struct trace_event *event)
1412{
1413 struct print_entry *field;
1414 struct trace_seq *s = &iter->seq;
1415
1416 trace_assign_type(field, iter->ent);
1417
1418 seq_print_ip_sym(s, field->ip, flags);
1419 trace_seq_printf(s, ": %s", field->buf);
1420
1421 return trace_handle_return(s);
1422}
1423
1424static enum print_line_t trace_print_raw(struct trace_iterator *iter, int flags,
1425 struct trace_event *event)
1426{
1427 struct print_entry *field;
1428
1429 trace_assign_type(field, iter->ent);
1430
1431 trace_seq_printf(&iter->seq, "# %lx %s", field->ip, field->buf);
1432
1433 return trace_handle_return(&iter->seq);
1434}
1435
1436static struct trace_event_functions trace_print_funcs = {
1437 .trace = trace_print_print,
1438 .raw = trace_print_raw,
1439};
1440
1441static struct trace_event trace_print_event = {
1442 .type = TRACE_PRINT,
1443 .funcs = &trace_print_funcs,
1444};
1445
1446static enum print_line_t trace_raw_data(struct trace_iterator *iter, int flags,
1447 struct trace_event *event)
1448{
1449 struct raw_data_entry *field;
1450 int i;
1451
1452 trace_assign_type(field, iter->ent);
1453
1454 trace_seq_printf(&iter->seq, "# %x buf:", field->id);
1455
1456 for (i = 0; i < iter->ent_size - offsetof(struct raw_data_entry, buf); i++)
1457 trace_seq_printf(&iter->seq, " %02x",
1458 (unsigned char)field->buf[i]);
1459
1460 trace_seq_putc(&iter->seq, '\n');
1461
1462 return trace_handle_return(&iter->seq);
1463}
1464
1465static struct trace_event_functions trace_raw_data_funcs = {
1466 .trace = trace_raw_data,
1467 .raw = trace_raw_data,
1468};
1469
1470static struct trace_event trace_raw_data_event = {
1471 .type = TRACE_RAW_DATA,
1472 .funcs = &trace_raw_data_funcs,
1473};
1474
1475static enum print_line_t
1476trace_func_repeats_raw(struct trace_iterator *iter, int flags,
1477 struct trace_event *event)
1478{
1479 struct func_repeats_entry *field;
1480 struct trace_seq *s = &iter->seq;
1481
1482 trace_assign_type(field, iter->ent);
1483
1484 trace_seq_printf(s, "%lu %lu %u %llu\n",
1485 field->ip,
1486 field->parent_ip,
1487 field->count,
1488 FUNC_REPEATS_GET_DELTA_TS(field));
1489
1490 return trace_handle_return(s);
1491}
1492
1493static enum print_line_t
1494trace_func_repeats_print(struct trace_iterator *iter, int flags,
1495 struct trace_event *event)
1496{
1497 struct func_repeats_entry *field;
1498 struct trace_seq *s = &iter->seq;
1499
1500 trace_assign_type(field, iter->ent);
1501
1502 print_fn_trace(s, field->ip, field->parent_ip, flags);
1503 trace_seq_printf(s, " (repeats: %u, last_ts:", field->count);
1504 trace_print_time(s, iter,
1505 iter->ts - FUNC_REPEATS_GET_DELTA_TS(field));
1506 trace_seq_puts(s, ")\n");
1507
1508 return trace_handle_return(s);
1509}
1510
1511static struct trace_event_functions trace_func_repeats_funcs = {
1512 .trace = trace_func_repeats_print,
1513 .raw = trace_func_repeats_raw,
1514};
1515
1516static struct trace_event trace_func_repeats_event = {
1517 .type = TRACE_FUNC_REPEATS,
1518 .funcs = &trace_func_repeats_funcs,
1519};
1520
1521static struct trace_event *events[] __initdata = {
1522 &trace_fn_event,
1523 &trace_ctx_event,
1524 &trace_wake_event,
1525 &trace_stack_event,
1526 &trace_user_stack_event,
1527 &trace_bputs_event,
1528 &trace_bprint_event,
1529 &trace_print_event,
1530 &trace_hwlat_event,
1531 &trace_osnoise_event,
1532 &trace_timerlat_event,
1533 &trace_raw_data_event,
1534 &trace_func_repeats_event,
1535 NULL
1536};
1537
1538__init int init_events(void)
1539{
1540 struct trace_event *event;
1541 int i, ret;
1542
1543 for (i = 0; events[i]; i++) {
1544 event = events[i];
1545 ret = register_trace_event(event);
1546 WARN_ONCE(!ret, "event %d failed to register", event->type);
1547 }
1548
1549 return 0;
1550}
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
19DECLARE_RWSEM(trace_event_sem);
20
21static struct hlist_head event_hash[EVENT_HASHSIZE] __read_mostly;
22
23static int next_event_type = __TRACE_LAST_TYPE;
24
25enum 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
38enum 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
51enum 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
64const char *
65trace_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}
100EXPORT_SYMBOL(trace_print_flags_seq);
101
102const char *
103trace_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}
125EXPORT_SYMBOL(trace_print_symbols_seq);
126
127#if BITS_PER_LONG == 32
128const char *
129trace_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}
164EXPORT_SYMBOL(trace_print_flags_seq_u64);
165
166const char *
167trace_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}
189EXPORT_SYMBOL(trace_print_symbols_seq_u64);
190#endif
191
192const char *
193trace_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}
203EXPORT_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 */
216const char *
217trace_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 const char *fmt = concatenate ? "%*phN" : "%*ph";
223
224 for (i = 0; i < buf_len; i += 16)
225 trace_seq_printf(p, fmt, min(buf_len - i, 16), &buf[i]);
226 trace_seq_putc(p, 0);
227
228 return ret;
229}
230EXPORT_SYMBOL(trace_print_hex_seq);
231
232const char *
233trace_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}
275EXPORT_SYMBOL(trace_print_array_seq);
276
277const char *
278trace_print_hex_dump_seq(struct trace_seq *p, const char *prefix_str,
279 int prefix_type, int rowsize, int groupsize,
280 const void *buf, size_t len, bool ascii)
281{
282 const char *ret = trace_seq_buffer_ptr(p);
283
284 trace_seq_putc(p, '\n');
285 trace_seq_hex_dump(p, prefix_str, prefix_type,
286 rowsize, groupsize, buf, len, ascii);
287 trace_seq_putc(p, 0);
288 return ret;
289}
290EXPORT_SYMBOL(trace_print_hex_dump_seq);
291
292int trace_raw_output_prep(struct trace_iterator *iter,
293 struct trace_event *trace_event)
294{
295 struct trace_event_call *event;
296 struct trace_seq *s = &iter->seq;
297 struct trace_seq *p = &iter->tmp_seq;
298 struct trace_entry *entry;
299
300 event = container_of(trace_event, struct trace_event_call, event);
301 entry = iter->ent;
302
303 if (entry->type != event->event.type) {
304 WARN_ON_ONCE(1);
305 return TRACE_TYPE_UNHANDLED;
306 }
307
308 trace_seq_init(p);
309 trace_seq_printf(s, "%s: ", trace_event_name(event));
310
311 return trace_handle_return(s);
312}
313EXPORT_SYMBOL(trace_raw_output_prep);
314
315void trace_event_printf(struct trace_iterator *iter, const char *fmt, ...)
316{
317 va_list ap;
318
319 va_start(ap, fmt);
320 trace_check_vprintf(iter, trace_event_format(iter, fmt), ap);
321 va_end(ap);
322}
323EXPORT_SYMBOL(trace_event_printf);
324
325static int trace_output_raw(struct trace_iterator *iter, char *name,
326 char *fmt, va_list ap)
327{
328 struct trace_seq *s = &iter->seq;
329
330 trace_seq_printf(s, "%s: ", name);
331 trace_seq_vprintf(s, trace_event_format(iter, fmt), ap);
332
333 return trace_handle_return(s);
334}
335
336int trace_output_call(struct trace_iterator *iter, char *name, char *fmt, ...)
337{
338 va_list ap;
339 int ret;
340
341 va_start(ap, fmt);
342 ret = trace_output_raw(iter, name, fmt, ap);
343 va_end(ap);
344
345 return ret;
346}
347EXPORT_SYMBOL_GPL(trace_output_call);
348
349#ifdef CONFIG_KRETPROBES
350static inline const char *kretprobed(const char *name)
351{
352 static const char tramp_name[] = "kretprobe_trampoline";
353 int size = sizeof(tramp_name);
354
355 if (strncmp(tramp_name, name, size) == 0)
356 return "[unknown/kretprobe'd]";
357 return name;
358}
359#else
360static inline const char *kretprobed(const char *name)
361{
362 return name;
363}
364#endif /* CONFIG_KRETPROBES */
365
366void
367trace_seq_print_sym(struct trace_seq *s, unsigned long address, bool offset)
368{
369#ifdef CONFIG_KALLSYMS
370 char str[KSYM_SYMBOL_LEN];
371 const char *name;
372
373 if (offset)
374 sprint_symbol(str, address);
375 else
376 kallsyms_lookup(address, NULL, NULL, NULL, str);
377 name = kretprobed(str);
378
379 if (name && strlen(name)) {
380 trace_seq_puts(s, name);
381 return;
382 }
383#endif
384 trace_seq_printf(s, "0x%08lx", address);
385}
386
387#ifndef CONFIG_64BIT
388# define IP_FMT "%08lx"
389#else
390# define IP_FMT "%016lx"
391#endif
392
393static int seq_print_user_ip(struct trace_seq *s, struct mm_struct *mm,
394 unsigned long ip, unsigned long sym_flags)
395{
396 struct file *file = NULL;
397 unsigned long vmstart = 0;
398 int ret = 1;
399
400 if (s->full)
401 return 0;
402
403 if (mm) {
404 const struct vm_area_struct *vma;
405
406 mmap_read_lock(mm);
407 vma = find_vma(mm, ip);
408 if (vma) {
409 file = vma->vm_file;
410 vmstart = vma->vm_start;
411 }
412 if (file) {
413 ret = trace_seq_path(s, &file->f_path);
414 if (ret)
415 trace_seq_printf(s, "[+0x%lx]",
416 ip - vmstart);
417 }
418 mmap_read_unlock(mm);
419 }
420 if (ret && ((sym_flags & TRACE_ITER_SYM_ADDR) || !file))
421 trace_seq_printf(s, " <" IP_FMT ">", ip);
422 return !trace_seq_has_overflowed(s);
423}
424
425int
426seq_print_ip_sym(struct trace_seq *s, unsigned long ip, unsigned long sym_flags)
427{
428 if (!ip) {
429 trace_seq_putc(s, '0');
430 goto out;
431 }
432
433 trace_seq_print_sym(s, ip, sym_flags & TRACE_ITER_SYM_OFFSET);
434
435 if (sym_flags & TRACE_ITER_SYM_ADDR)
436 trace_seq_printf(s, " <" IP_FMT ">", ip);
437
438 out:
439 return !trace_seq_has_overflowed(s);
440}
441
442/**
443 * trace_print_lat_fmt - print the irq, preempt and lockdep fields
444 * @s: trace seq struct to write to
445 * @entry: The trace entry field from the ring buffer
446 *
447 * Prints the generic fields of irqs off, in hard or softirq, preempt
448 * count.
449 */
450int trace_print_lat_fmt(struct trace_seq *s, struct trace_entry *entry)
451{
452 char hardsoft_irq;
453 char need_resched;
454 char irqs_off;
455 int hardirq;
456 int softirq;
457 int nmi;
458
459 nmi = entry->flags & TRACE_FLAG_NMI;
460 hardirq = entry->flags & TRACE_FLAG_HARDIRQ;
461 softirq = entry->flags & TRACE_FLAG_SOFTIRQ;
462
463 irqs_off =
464 (entry->flags & TRACE_FLAG_IRQS_OFF) ? 'd' :
465 (entry->flags & TRACE_FLAG_IRQS_NOSUPPORT) ? 'X' :
466 '.';
467
468 switch (entry->flags & (TRACE_FLAG_NEED_RESCHED |
469 TRACE_FLAG_PREEMPT_RESCHED)) {
470 case TRACE_FLAG_NEED_RESCHED | TRACE_FLAG_PREEMPT_RESCHED:
471 need_resched = 'N';
472 break;
473 case TRACE_FLAG_NEED_RESCHED:
474 need_resched = 'n';
475 break;
476 case TRACE_FLAG_PREEMPT_RESCHED:
477 need_resched = 'p';
478 break;
479 default:
480 need_resched = '.';
481 break;
482 }
483
484 hardsoft_irq =
485 (nmi && hardirq) ? 'Z' :
486 nmi ? 'z' :
487 (hardirq && softirq) ? 'H' :
488 hardirq ? 'h' :
489 softirq ? 's' :
490 '.' ;
491
492 trace_seq_printf(s, "%c%c%c",
493 irqs_off, need_resched, hardsoft_irq);
494
495 if (entry->preempt_count)
496 trace_seq_printf(s, "%x", entry->preempt_count);
497 else
498 trace_seq_putc(s, '.');
499
500 return !trace_seq_has_overflowed(s);
501}
502
503static int
504lat_print_generic(struct trace_seq *s, struct trace_entry *entry, int cpu)
505{
506 char comm[TASK_COMM_LEN];
507
508 trace_find_cmdline(entry->pid, comm);
509
510 trace_seq_printf(s, "%8.8s-%-7d %3d",
511 comm, entry->pid, cpu);
512
513 return trace_print_lat_fmt(s, entry);
514}
515
516#undef MARK
517#define MARK(v, s) {.val = v, .sym = s}
518/* trace overhead mark */
519static const struct trace_mark {
520 unsigned long long val; /* unit: nsec */
521 char sym;
522} mark[] = {
523 MARK(1000000000ULL , '$'), /* 1 sec */
524 MARK(100000000ULL , '@'), /* 100 msec */
525 MARK(10000000ULL , '*'), /* 10 msec */
526 MARK(1000000ULL , '#'), /* 1000 usecs */
527 MARK(100000ULL , '!'), /* 100 usecs */
528 MARK(10000ULL , '+'), /* 10 usecs */
529};
530#undef MARK
531
532char trace_find_mark(unsigned long long d)
533{
534 int i;
535 int size = ARRAY_SIZE(mark);
536
537 for (i = 0; i < size; i++) {
538 if (d > mark[i].val)
539 break;
540 }
541
542 return (i == size) ? ' ' : mark[i].sym;
543}
544
545static int
546lat_print_timestamp(struct trace_iterator *iter, u64 next_ts)
547{
548 struct trace_array *tr = iter->tr;
549 unsigned long verbose = tr->trace_flags & TRACE_ITER_VERBOSE;
550 unsigned long in_ns = iter->iter_flags & TRACE_FILE_TIME_IN_NS;
551 unsigned long long abs_ts = iter->ts - iter->array_buffer->time_start;
552 unsigned long long rel_ts = next_ts - iter->ts;
553 struct trace_seq *s = &iter->seq;
554
555 if (in_ns) {
556 abs_ts = ns2usecs(abs_ts);
557 rel_ts = ns2usecs(rel_ts);
558 }
559
560 if (verbose && in_ns) {
561 unsigned long abs_usec = do_div(abs_ts, USEC_PER_MSEC);
562 unsigned long abs_msec = (unsigned long)abs_ts;
563 unsigned long rel_usec = do_div(rel_ts, USEC_PER_MSEC);
564 unsigned long rel_msec = (unsigned long)rel_ts;
565
566 trace_seq_printf(
567 s, "[%08llx] %ld.%03ldms (+%ld.%03ldms): ",
568 ns2usecs(iter->ts),
569 abs_msec, abs_usec,
570 rel_msec, rel_usec);
571
572 } else if (verbose && !in_ns) {
573 trace_seq_printf(
574 s, "[%016llx] %lld (+%lld): ",
575 iter->ts, abs_ts, rel_ts);
576
577 } else if (!verbose && in_ns) {
578 trace_seq_printf(
579 s, " %4lldus%c: ",
580 abs_ts,
581 trace_find_mark(rel_ts * NSEC_PER_USEC));
582
583 } else { /* !verbose && !in_ns */
584 trace_seq_printf(s, " %4lld: ", abs_ts);
585 }
586
587 return !trace_seq_has_overflowed(s);
588}
589
590static void trace_print_time(struct trace_seq *s, struct trace_iterator *iter,
591 unsigned long long ts)
592{
593 unsigned long secs, usec_rem;
594 unsigned long long t;
595
596 if (iter->iter_flags & TRACE_FILE_TIME_IN_NS) {
597 t = ns2usecs(ts);
598 usec_rem = do_div(t, USEC_PER_SEC);
599 secs = (unsigned long)t;
600 trace_seq_printf(s, " %5lu.%06lu", secs, usec_rem);
601 } else
602 trace_seq_printf(s, " %12llu", ts);
603}
604
605int trace_print_context(struct trace_iterator *iter)
606{
607 struct trace_array *tr = iter->tr;
608 struct trace_seq *s = &iter->seq;
609 struct trace_entry *entry = iter->ent;
610 char comm[TASK_COMM_LEN];
611
612 trace_find_cmdline(entry->pid, comm);
613
614 trace_seq_printf(s, "%16s-%-7d ", comm, entry->pid);
615
616 if (tr->trace_flags & TRACE_ITER_RECORD_TGID) {
617 unsigned int tgid = trace_find_tgid(entry->pid);
618
619 if (!tgid)
620 trace_seq_printf(s, "(-------) ");
621 else
622 trace_seq_printf(s, "(%7d) ", tgid);
623 }
624
625 trace_seq_printf(s, "[%03d] ", iter->cpu);
626
627 if (tr->trace_flags & TRACE_ITER_IRQ_INFO)
628 trace_print_lat_fmt(s, entry);
629
630 trace_print_time(s, iter, iter->ts);
631 trace_seq_puts(s, ": ");
632
633 return !trace_seq_has_overflowed(s);
634}
635
636int trace_print_lat_context(struct trace_iterator *iter)
637{
638 struct trace_entry *entry, *next_entry;
639 struct trace_array *tr = iter->tr;
640 struct trace_seq *s = &iter->seq;
641 unsigned long verbose = (tr->trace_flags & TRACE_ITER_VERBOSE);
642 u64 next_ts;
643
644 next_entry = trace_find_next_entry(iter, NULL, &next_ts);
645 if (!next_entry)
646 next_ts = iter->ts;
647
648 /* trace_find_next_entry() may change iter->ent */
649 entry = iter->ent;
650
651 if (verbose) {
652 char comm[TASK_COMM_LEN];
653
654 trace_find_cmdline(entry->pid, comm);
655
656 trace_seq_printf(
657 s, "%16s %7d %3d %d %08x %08lx ",
658 comm, entry->pid, iter->cpu, entry->flags,
659 entry->preempt_count, iter->idx);
660 } else {
661 lat_print_generic(s, entry, iter->cpu);
662 }
663
664 lat_print_timestamp(iter, next_ts);
665
666 return !trace_seq_has_overflowed(s);
667}
668
669/**
670 * ftrace_find_event - find a registered event
671 * @type: the type of event to look for
672 *
673 * Returns an event of type @type otherwise NULL
674 * Called with trace_event_read_lock() held.
675 */
676struct trace_event *ftrace_find_event(int type)
677{
678 struct trace_event *event;
679 unsigned key;
680
681 key = type & (EVENT_HASHSIZE - 1);
682
683 hlist_for_each_entry(event, &event_hash[key], node) {
684 if (event->type == type)
685 return event;
686 }
687
688 return NULL;
689}
690
691static LIST_HEAD(ftrace_event_list);
692
693static int trace_search_list(struct list_head **list)
694{
695 struct trace_event *e;
696 int next = __TRACE_LAST_TYPE;
697
698 if (list_empty(&ftrace_event_list)) {
699 *list = &ftrace_event_list;
700 return next;
701 }
702
703 /*
704 * We used up all possible max events,
705 * lets see if somebody freed one.
706 */
707 list_for_each_entry(e, &ftrace_event_list, list) {
708 if (e->type != next)
709 break;
710 next++;
711 }
712
713 /* Did we used up all 65 thousand events??? */
714 if (next > TRACE_EVENT_TYPE_MAX)
715 return 0;
716
717 *list = &e->list;
718 return next;
719}
720
721void trace_event_read_lock(void)
722{
723 down_read(&trace_event_sem);
724}
725
726void trace_event_read_unlock(void)
727{
728 up_read(&trace_event_sem);
729}
730
731/**
732 * register_trace_event - register output for an event type
733 * @event: the event type to register
734 *
735 * Event types are stored in a hash and this hash is used to
736 * find a way to print an event. If the @event->type is set
737 * then it will use that type, otherwise it will assign a
738 * type to use.
739 *
740 * If you assign your own type, please make sure it is added
741 * to the trace_type enum in trace.h, to avoid collisions
742 * with the dynamic types.
743 *
744 * Returns the event type number or zero on error.
745 */
746int register_trace_event(struct trace_event *event)
747{
748 unsigned key;
749 int ret = 0;
750
751 down_write(&trace_event_sem);
752
753 if (WARN_ON(!event))
754 goto out;
755
756 if (WARN_ON(!event->funcs))
757 goto out;
758
759 INIT_LIST_HEAD(&event->list);
760
761 if (!event->type) {
762 struct list_head *list = NULL;
763
764 if (next_event_type > TRACE_EVENT_TYPE_MAX) {
765
766 event->type = trace_search_list(&list);
767 if (!event->type)
768 goto out;
769
770 } else {
771
772 event->type = next_event_type++;
773 list = &ftrace_event_list;
774 }
775
776 if (WARN_ON(ftrace_find_event(event->type)))
777 goto out;
778
779 list_add_tail(&event->list, list);
780
781 } else if (event->type > __TRACE_LAST_TYPE) {
782 printk(KERN_WARNING "Need to add type to trace.h\n");
783 WARN_ON(1);
784 goto out;
785 } else {
786 /* Is this event already used */
787 if (ftrace_find_event(event->type))
788 goto out;
789 }
790
791 if (event->funcs->trace == NULL)
792 event->funcs->trace = trace_nop_print;
793 if (event->funcs->raw == NULL)
794 event->funcs->raw = trace_nop_print;
795 if (event->funcs->hex == NULL)
796 event->funcs->hex = trace_nop_print;
797 if (event->funcs->binary == NULL)
798 event->funcs->binary = trace_nop_print;
799
800 key = event->type & (EVENT_HASHSIZE - 1);
801
802 hlist_add_head(&event->node, &event_hash[key]);
803
804 ret = event->type;
805 out:
806 up_write(&trace_event_sem);
807
808 return ret;
809}
810EXPORT_SYMBOL_GPL(register_trace_event);
811
812/*
813 * Used by module code with the trace_event_sem held for write.
814 */
815int __unregister_trace_event(struct trace_event *event)
816{
817 hlist_del(&event->node);
818 list_del(&event->list);
819 return 0;
820}
821
822/**
823 * unregister_trace_event - remove a no longer used event
824 * @event: the event to remove
825 */
826int unregister_trace_event(struct trace_event *event)
827{
828 down_write(&trace_event_sem);
829 __unregister_trace_event(event);
830 up_write(&trace_event_sem);
831
832 return 0;
833}
834EXPORT_SYMBOL_GPL(unregister_trace_event);
835
836/*
837 * Standard events
838 */
839
840enum print_line_t trace_nop_print(struct trace_iterator *iter, int flags,
841 struct trace_event *event)
842{
843 trace_seq_printf(&iter->seq, "type: %d\n", iter->ent->type);
844
845 return trace_handle_return(&iter->seq);
846}
847
848static void print_fn_trace(struct trace_seq *s, unsigned long ip,
849 unsigned long parent_ip, int flags)
850{
851 seq_print_ip_sym(s, ip, flags);
852
853 if ((flags & TRACE_ITER_PRINT_PARENT) && parent_ip) {
854 trace_seq_puts(s, " <-");
855 seq_print_ip_sym(s, parent_ip, flags);
856 }
857}
858
859/* TRACE_FN */
860static enum print_line_t trace_fn_trace(struct trace_iterator *iter, int flags,
861 struct trace_event *event)
862{
863 struct ftrace_entry *field;
864 struct trace_seq *s = &iter->seq;
865
866 trace_assign_type(field, iter->ent);
867
868 print_fn_trace(s, field->ip, field->parent_ip, flags);
869 trace_seq_putc(s, '\n');
870
871 return trace_handle_return(s);
872}
873
874static enum print_line_t trace_fn_raw(struct trace_iterator *iter, int flags,
875 struct trace_event *event)
876{
877 struct ftrace_entry *field;
878
879 trace_assign_type(field, iter->ent);
880
881 trace_seq_printf(&iter->seq, "%lx %lx\n",
882 field->ip,
883 field->parent_ip);
884
885 return trace_handle_return(&iter->seq);
886}
887
888static enum print_line_t trace_fn_hex(struct trace_iterator *iter, int flags,
889 struct trace_event *event)
890{
891 struct ftrace_entry *field;
892 struct trace_seq *s = &iter->seq;
893
894 trace_assign_type(field, iter->ent);
895
896 SEQ_PUT_HEX_FIELD(s, field->ip);
897 SEQ_PUT_HEX_FIELD(s, field->parent_ip);
898
899 return trace_handle_return(s);
900}
901
902static enum print_line_t trace_fn_bin(struct trace_iterator *iter, int flags,
903 struct trace_event *event)
904{
905 struct ftrace_entry *field;
906 struct trace_seq *s = &iter->seq;
907
908 trace_assign_type(field, iter->ent);
909
910 SEQ_PUT_FIELD(s, field->ip);
911 SEQ_PUT_FIELD(s, field->parent_ip);
912
913 return trace_handle_return(s);
914}
915
916static struct trace_event_functions trace_fn_funcs = {
917 .trace = trace_fn_trace,
918 .raw = trace_fn_raw,
919 .hex = trace_fn_hex,
920 .binary = trace_fn_bin,
921};
922
923static struct trace_event trace_fn_event = {
924 .type = TRACE_FN,
925 .funcs = &trace_fn_funcs,
926};
927
928/* TRACE_CTX an TRACE_WAKE */
929static enum print_line_t trace_ctxwake_print(struct trace_iterator *iter,
930 char *delim)
931{
932 struct ctx_switch_entry *field;
933 char comm[TASK_COMM_LEN];
934 int S, T;
935
936
937 trace_assign_type(field, iter->ent);
938
939 T = task_index_to_char(field->next_state);
940 S = task_index_to_char(field->prev_state);
941 trace_find_cmdline(field->next_pid, comm);
942 trace_seq_printf(&iter->seq,
943 " %7d:%3d:%c %s [%03d] %7d:%3d:%c %s\n",
944 field->prev_pid,
945 field->prev_prio,
946 S, delim,
947 field->next_cpu,
948 field->next_pid,
949 field->next_prio,
950 T, comm);
951
952 return trace_handle_return(&iter->seq);
953}
954
955static enum print_line_t trace_ctx_print(struct trace_iterator *iter, int flags,
956 struct trace_event *event)
957{
958 return trace_ctxwake_print(iter, "==>");
959}
960
961static enum print_line_t trace_wake_print(struct trace_iterator *iter,
962 int flags, struct trace_event *event)
963{
964 return trace_ctxwake_print(iter, " +");
965}
966
967static int trace_ctxwake_raw(struct trace_iterator *iter, char S)
968{
969 struct ctx_switch_entry *field;
970 int T;
971
972 trace_assign_type(field, iter->ent);
973
974 if (!S)
975 S = task_index_to_char(field->prev_state);
976 T = task_index_to_char(field->next_state);
977 trace_seq_printf(&iter->seq, "%d %d %c %d %d %d %c\n",
978 field->prev_pid,
979 field->prev_prio,
980 S,
981 field->next_cpu,
982 field->next_pid,
983 field->next_prio,
984 T);
985
986 return trace_handle_return(&iter->seq);
987}
988
989static enum print_line_t trace_ctx_raw(struct trace_iterator *iter, int flags,
990 struct trace_event *event)
991{
992 return trace_ctxwake_raw(iter, 0);
993}
994
995static enum print_line_t trace_wake_raw(struct trace_iterator *iter, int flags,
996 struct trace_event *event)
997{
998 return trace_ctxwake_raw(iter, '+');
999}
1000
1001
1002static int trace_ctxwake_hex(struct trace_iterator *iter, char S)
1003{
1004 struct ctx_switch_entry *field;
1005 struct trace_seq *s = &iter->seq;
1006 int T;
1007
1008 trace_assign_type(field, iter->ent);
1009
1010 if (!S)
1011 S = task_index_to_char(field->prev_state);
1012 T = task_index_to_char(field->next_state);
1013
1014 SEQ_PUT_HEX_FIELD(s, field->prev_pid);
1015 SEQ_PUT_HEX_FIELD(s, field->prev_prio);
1016 SEQ_PUT_HEX_FIELD(s, S);
1017 SEQ_PUT_HEX_FIELD(s, field->next_cpu);
1018 SEQ_PUT_HEX_FIELD(s, field->next_pid);
1019 SEQ_PUT_HEX_FIELD(s, field->next_prio);
1020 SEQ_PUT_HEX_FIELD(s, T);
1021
1022 return trace_handle_return(s);
1023}
1024
1025static enum print_line_t trace_ctx_hex(struct trace_iterator *iter, int flags,
1026 struct trace_event *event)
1027{
1028 return trace_ctxwake_hex(iter, 0);
1029}
1030
1031static enum print_line_t trace_wake_hex(struct trace_iterator *iter, int flags,
1032 struct trace_event *event)
1033{
1034 return trace_ctxwake_hex(iter, '+');
1035}
1036
1037static enum print_line_t trace_ctxwake_bin(struct trace_iterator *iter,
1038 int flags, struct trace_event *event)
1039{
1040 struct ctx_switch_entry *field;
1041 struct trace_seq *s = &iter->seq;
1042
1043 trace_assign_type(field, iter->ent);
1044
1045 SEQ_PUT_FIELD(s, field->prev_pid);
1046 SEQ_PUT_FIELD(s, field->prev_prio);
1047 SEQ_PUT_FIELD(s, field->prev_state);
1048 SEQ_PUT_FIELD(s, field->next_cpu);
1049 SEQ_PUT_FIELD(s, field->next_pid);
1050 SEQ_PUT_FIELD(s, field->next_prio);
1051 SEQ_PUT_FIELD(s, field->next_state);
1052
1053 return trace_handle_return(s);
1054}
1055
1056static struct trace_event_functions trace_ctx_funcs = {
1057 .trace = trace_ctx_print,
1058 .raw = trace_ctx_raw,
1059 .hex = trace_ctx_hex,
1060 .binary = trace_ctxwake_bin,
1061};
1062
1063static struct trace_event trace_ctx_event = {
1064 .type = TRACE_CTX,
1065 .funcs = &trace_ctx_funcs,
1066};
1067
1068static struct trace_event_functions trace_wake_funcs = {
1069 .trace = trace_wake_print,
1070 .raw = trace_wake_raw,
1071 .hex = trace_wake_hex,
1072 .binary = trace_ctxwake_bin,
1073};
1074
1075static struct trace_event trace_wake_event = {
1076 .type = TRACE_WAKE,
1077 .funcs = &trace_wake_funcs,
1078};
1079
1080/* TRACE_STACK */
1081
1082static enum print_line_t trace_stack_print(struct trace_iterator *iter,
1083 int flags, struct trace_event *event)
1084{
1085 struct stack_entry *field;
1086 struct trace_seq *s = &iter->seq;
1087 unsigned long *p;
1088 unsigned long *end;
1089
1090 trace_assign_type(field, iter->ent);
1091 end = (unsigned long *)((long)iter->ent + iter->ent_size);
1092
1093 trace_seq_puts(s, "<stack trace>\n");
1094
1095 for (p = field->caller; p && p < end && *p != ULONG_MAX; p++) {
1096
1097 if (trace_seq_has_overflowed(s))
1098 break;
1099
1100 trace_seq_puts(s, " => ");
1101 seq_print_ip_sym(s, *p, flags);
1102 trace_seq_putc(s, '\n');
1103 }
1104
1105 return trace_handle_return(s);
1106}
1107
1108static struct trace_event_functions trace_stack_funcs = {
1109 .trace = trace_stack_print,
1110};
1111
1112static struct trace_event trace_stack_event = {
1113 .type = TRACE_STACK,
1114 .funcs = &trace_stack_funcs,
1115};
1116
1117/* TRACE_USER_STACK */
1118static enum print_line_t trace_user_stack_print(struct trace_iterator *iter,
1119 int flags, struct trace_event *event)
1120{
1121 struct trace_array *tr = iter->tr;
1122 struct userstack_entry *field;
1123 struct trace_seq *s = &iter->seq;
1124 struct mm_struct *mm = NULL;
1125 unsigned int i;
1126
1127 trace_assign_type(field, iter->ent);
1128
1129 trace_seq_puts(s, "<user stack trace>\n");
1130
1131 if (tr->trace_flags & TRACE_ITER_SYM_USEROBJ) {
1132 struct task_struct *task;
1133 /*
1134 * we do the lookup on the thread group leader,
1135 * since individual threads might have already quit!
1136 */
1137 rcu_read_lock();
1138 task = find_task_by_vpid(field->tgid);
1139 if (task)
1140 mm = get_task_mm(task);
1141 rcu_read_unlock();
1142 }
1143
1144 for (i = 0; i < FTRACE_STACK_ENTRIES; i++) {
1145 unsigned long ip = field->caller[i];
1146
1147 if (!ip || trace_seq_has_overflowed(s))
1148 break;
1149
1150 trace_seq_puts(s, " => ");
1151 seq_print_user_ip(s, mm, ip, flags);
1152 trace_seq_putc(s, '\n');
1153 }
1154
1155 if (mm)
1156 mmput(mm);
1157
1158 return trace_handle_return(s);
1159}
1160
1161static struct trace_event_functions trace_user_stack_funcs = {
1162 .trace = trace_user_stack_print,
1163};
1164
1165static struct trace_event trace_user_stack_event = {
1166 .type = TRACE_USER_STACK,
1167 .funcs = &trace_user_stack_funcs,
1168};
1169
1170/* TRACE_HWLAT */
1171static enum print_line_t
1172trace_hwlat_print(struct trace_iterator *iter, int flags,
1173 struct trace_event *event)
1174{
1175 struct trace_entry *entry = iter->ent;
1176 struct trace_seq *s = &iter->seq;
1177 struct hwlat_entry *field;
1178
1179 trace_assign_type(field, entry);
1180
1181 trace_seq_printf(s, "#%-5u inner/outer(us): %4llu/%-5llu ts:%lld.%09ld count:%d",
1182 field->seqnum,
1183 field->duration,
1184 field->outer_duration,
1185 (long long)field->timestamp.tv_sec,
1186 field->timestamp.tv_nsec, field->count);
1187
1188 if (field->nmi_count) {
1189 /*
1190 * The generic sched_clock() is not NMI safe, thus
1191 * we only record the count and not the time.
1192 */
1193 if (!IS_ENABLED(CONFIG_GENERIC_SCHED_CLOCK))
1194 trace_seq_printf(s, " nmi-total:%llu",
1195 field->nmi_total_ts);
1196 trace_seq_printf(s, " nmi-count:%u",
1197 field->nmi_count);
1198 }
1199
1200 trace_seq_putc(s, '\n');
1201
1202 return trace_handle_return(s);
1203}
1204
1205static enum print_line_t
1206trace_hwlat_raw(struct trace_iterator *iter, int flags,
1207 struct trace_event *event)
1208{
1209 struct hwlat_entry *field;
1210 struct trace_seq *s = &iter->seq;
1211
1212 trace_assign_type(field, iter->ent);
1213
1214 trace_seq_printf(s, "%llu %lld %lld %09ld %u\n",
1215 field->duration,
1216 field->outer_duration,
1217 (long long)field->timestamp.tv_sec,
1218 field->timestamp.tv_nsec,
1219 field->seqnum);
1220
1221 return trace_handle_return(s);
1222}
1223
1224static struct trace_event_functions trace_hwlat_funcs = {
1225 .trace = trace_hwlat_print,
1226 .raw = trace_hwlat_raw,
1227};
1228
1229static struct trace_event trace_hwlat_event = {
1230 .type = TRACE_HWLAT,
1231 .funcs = &trace_hwlat_funcs,
1232};
1233
1234/* TRACE_OSNOISE */
1235static enum print_line_t
1236trace_osnoise_print(struct trace_iterator *iter, int flags,
1237 struct trace_event *event)
1238{
1239 struct trace_entry *entry = iter->ent;
1240 struct trace_seq *s = &iter->seq;
1241 struct osnoise_entry *field;
1242 u64 ratio, ratio_dec;
1243 u64 net_runtime;
1244
1245 trace_assign_type(field, entry);
1246
1247 /*
1248 * compute the available % of cpu time.
1249 */
1250 net_runtime = field->runtime - field->noise;
1251 ratio = net_runtime * 10000000;
1252 do_div(ratio, field->runtime);
1253 ratio_dec = do_div(ratio, 100000);
1254
1255 trace_seq_printf(s, "%llu %10llu %3llu.%05llu %7llu",
1256 field->runtime,
1257 field->noise,
1258 ratio, ratio_dec,
1259 field->max_sample);
1260
1261 trace_seq_printf(s, " %6u", field->hw_count);
1262 trace_seq_printf(s, " %6u", field->nmi_count);
1263 trace_seq_printf(s, " %6u", field->irq_count);
1264 trace_seq_printf(s, " %6u", field->softirq_count);
1265 trace_seq_printf(s, " %6u", field->thread_count);
1266
1267 trace_seq_putc(s, '\n');
1268
1269 return trace_handle_return(s);
1270}
1271
1272static enum print_line_t
1273trace_osnoise_raw(struct trace_iterator *iter, int flags,
1274 struct trace_event *event)
1275{
1276 struct osnoise_entry *field;
1277 struct trace_seq *s = &iter->seq;
1278
1279 trace_assign_type(field, iter->ent);
1280
1281 trace_seq_printf(s, "%lld %llu %llu %u %u %u %u %u\n",
1282 field->runtime,
1283 field->noise,
1284 field->max_sample,
1285 field->hw_count,
1286 field->nmi_count,
1287 field->irq_count,
1288 field->softirq_count,
1289 field->thread_count);
1290
1291 return trace_handle_return(s);
1292}
1293
1294static struct trace_event_functions trace_osnoise_funcs = {
1295 .trace = trace_osnoise_print,
1296 .raw = trace_osnoise_raw,
1297};
1298
1299static struct trace_event trace_osnoise_event = {
1300 .type = TRACE_OSNOISE,
1301 .funcs = &trace_osnoise_funcs,
1302};
1303
1304/* TRACE_TIMERLAT */
1305static enum print_line_t
1306trace_timerlat_print(struct trace_iterator *iter, int flags,
1307 struct trace_event *event)
1308{
1309 struct trace_entry *entry = iter->ent;
1310 struct trace_seq *s = &iter->seq;
1311 struct timerlat_entry *field;
1312
1313 trace_assign_type(field, entry);
1314
1315 trace_seq_printf(s, "#%-5u context %6s timer_latency %9llu ns\n",
1316 field->seqnum,
1317 field->context ? "thread" : "irq",
1318 field->timer_latency);
1319
1320 return trace_handle_return(s);
1321}
1322
1323static enum print_line_t
1324trace_timerlat_raw(struct trace_iterator *iter, int flags,
1325 struct trace_event *event)
1326{
1327 struct timerlat_entry *field;
1328 struct trace_seq *s = &iter->seq;
1329
1330 trace_assign_type(field, iter->ent);
1331
1332 trace_seq_printf(s, "%u %d %llu\n",
1333 field->seqnum,
1334 field->context,
1335 field->timer_latency);
1336
1337 return trace_handle_return(s);
1338}
1339
1340static struct trace_event_functions trace_timerlat_funcs = {
1341 .trace = trace_timerlat_print,
1342 .raw = trace_timerlat_raw,
1343};
1344
1345static struct trace_event trace_timerlat_event = {
1346 .type = TRACE_TIMERLAT,
1347 .funcs = &trace_timerlat_funcs,
1348};
1349
1350/* TRACE_BPUTS */
1351static enum print_line_t
1352trace_bputs_print(struct trace_iterator *iter, int flags,
1353 struct trace_event *event)
1354{
1355 struct trace_entry *entry = iter->ent;
1356 struct trace_seq *s = &iter->seq;
1357 struct bputs_entry *field;
1358
1359 trace_assign_type(field, entry);
1360
1361 seq_print_ip_sym(s, field->ip, flags);
1362 trace_seq_puts(s, ": ");
1363 trace_seq_puts(s, field->str);
1364
1365 return trace_handle_return(s);
1366}
1367
1368
1369static enum print_line_t
1370trace_bputs_raw(struct trace_iterator *iter, int flags,
1371 struct trace_event *event)
1372{
1373 struct bputs_entry *field;
1374 struct trace_seq *s = &iter->seq;
1375
1376 trace_assign_type(field, iter->ent);
1377
1378 trace_seq_printf(s, ": %lx : ", field->ip);
1379 trace_seq_puts(s, field->str);
1380
1381 return trace_handle_return(s);
1382}
1383
1384static struct trace_event_functions trace_bputs_funcs = {
1385 .trace = trace_bputs_print,
1386 .raw = trace_bputs_raw,
1387};
1388
1389static struct trace_event trace_bputs_event = {
1390 .type = TRACE_BPUTS,
1391 .funcs = &trace_bputs_funcs,
1392};
1393
1394/* TRACE_BPRINT */
1395static enum print_line_t
1396trace_bprint_print(struct trace_iterator *iter, int flags,
1397 struct trace_event *event)
1398{
1399 struct trace_entry *entry = iter->ent;
1400 struct trace_seq *s = &iter->seq;
1401 struct bprint_entry *field;
1402
1403 trace_assign_type(field, entry);
1404
1405 seq_print_ip_sym(s, field->ip, flags);
1406 trace_seq_puts(s, ": ");
1407 trace_seq_bprintf(s, field->fmt, field->buf);
1408
1409 return trace_handle_return(s);
1410}
1411
1412
1413static enum print_line_t
1414trace_bprint_raw(struct trace_iterator *iter, int flags,
1415 struct trace_event *event)
1416{
1417 struct bprint_entry *field;
1418 struct trace_seq *s = &iter->seq;
1419
1420 trace_assign_type(field, iter->ent);
1421
1422 trace_seq_printf(s, ": %lx : ", field->ip);
1423 trace_seq_bprintf(s, field->fmt, field->buf);
1424
1425 return trace_handle_return(s);
1426}
1427
1428static struct trace_event_functions trace_bprint_funcs = {
1429 .trace = trace_bprint_print,
1430 .raw = trace_bprint_raw,
1431};
1432
1433static struct trace_event trace_bprint_event = {
1434 .type = TRACE_BPRINT,
1435 .funcs = &trace_bprint_funcs,
1436};
1437
1438/* TRACE_PRINT */
1439static enum print_line_t trace_print_print(struct trace_iterator *iter,
1440 int flags, struct trace_event *event)
1441{
1442 struct print_entry *field;
1443 struct trace_seq *s = &iter->seq;
1444
1445 trace_assign_type(field, iter->ent);
1446
1447 seq_print_ip_sym(s, field->ip, flags);
1448 trace_seq_printf(s, ": %s", field->buf);
1449
1450 return trace_handle_return(s);
1451}
1452
1453static enum print_line_t trace_print_raw(struct trace_iterator *iter, int flags,
1454 struct trace_event *event)
1455{
1456 struct print_entry *field;
1457
1458 trace_assign_type(field, iter->ent);
1459
1460 trace_seq_printf(&iter->seq, "# %lx %s", field->ip, field->buf);
1461
1462 return trace_handle_return(&iter->seq);
1463}
1464
1465static struct trace_event_functions trace_print_funcs = {
1466 .trace = trace_print_print,
1467 .raw = trace_print_raw,
1468};
1469
1470static struct trace_event trace_print_event = {
1471 .type = TRACE_PRINT,
1472 .funcs = &trace_print_funcs,
1473};
1474
1475static enum print_line_t trace_raw_data(struct trace_iterator *iter, int flags,
1476 struct trace_event *event)
1477{
1478 struct raw_data_entry *field;
1479 int i;
1480
1481 trace_assign_type(field, iter->ent);
1482
1483 trace_seq_printf(&iter->seq, "# %x buf:", field->id);
1484
1485 for (i = 0; i < iter->ent_size - offsetof(struct raw_data_entry, buf); i++)
1486 trace_seq_printf(&iter->seq, " %02x",
1487 (unsigned char)field->buf[i]);
1488
1489 trace_seq_putc(&iter->seq, '\n');
1490
1491 return trace_handle_return(&iter->seq);
1492}
1493
1494static struct trace_event_functions trace_raw_data_funcs = {
1495 .trace = trace_raw_data,
1496 .raw = trace_raw_data,
1497};
1498
1499static struct trace_event trace_raw_data_event = {
1500 .type = TRACE_RAW_DATA,
1501 .funcs = &trace_raw_data_funcs,
1502};
1503
1504static enum print_line_t
1505trace_func_repeats_raw(struct trace_iterator *iter, int flags,
1506 struct trace_event *event)
1507{
1508 struct func_repeats_entry *field;
1509 struct trace_seq *s = &iter->seq;
1510
1511 trace_assign_type(field, iter->ent);
1512
1513 trace_seq_printf(s, "%lu %lu %u %llu\n",
1514 field->ip,
1515 field->parent_ip,
1516 field->count,
1517 FUNC_REPEATS_GET_DELTA_TS(field));
1518
1519 return trace_handle_return(s);
1520}
1521
1522static enum print_line_t
1523trace_func_repeats_print(struct trace_iterator *iter, int flags,
1524 struct trace_event *event)
1525{
1526 struct func_repeats_entry *field;
1527 struct trace_seq *s = &iter->seq;
1528
1529 trace_assign_type(field, iter->ent);
1530
1531 print_fn_trace(s, field->ip, field->parent_ip, flags);
1532 trace_seq_printf(s, " (repeats: %u, last_ts:", field->count);
1533 trace_print_time(s, iter,
1534 iter->ts - FUNC_REPEATS_GET_DELTA_TS(field));
1535 trace_seq_puts(s, ")\n");
1536
1537 return trace_handle_return(s);
1538}
1539
1540static struct trace_event_functions trace_func_repeats_funcs = {
1541 .trace = trace_func_repeats_print,
1542 .raw = trace_func_repeats_raw,
1543};
1544
1545static struct trace_event trace_func_repeats_event = {
1546 .type = TRACE_FUNC_REPEATS,
1547 .funcs = &trace_func_repeats_funcs,
1548};
1549
1550static struct trace_event *events[] __initdata = {
1551 &trace_fn_event,
1552 &trace_ctx_event,
1553 &trace_wake_event,
1554 &trace_stack_event,
1555 &trace_user_stack_event,
1556 &trace_bputs_event,
1557 &trace_bprint_event,
1558 &trace_print_event,
1559 &trace_hwlat_event,
1560 &trace_osnoise_event,
1561 &trace_timerlat_event,
1562 &trace_raw_data_event,
1563 &trace_func_repeats_event,
1564 NULL
1565};
1566
1567__init static int init_events(void)
1568{
1569 struct trace_event *event;
1570 int i, ret;
1571
1572 for (i = 0; events[i]; i++) {
1573 event = events[i];
1574
1575 ret = register_trace_event(event);
1576 if (!ret) {
1577 printk(KERN_WARNING "event %d failed to register\n",
1578 event->type);
1579 WARN_ON_ONCE(1);
1580 }
1581 }
1582
1583 return 0;
1584}
1585early_initcall(init_events);