xref: /linux/kernel/trace/trace_output.c (revision e27ecdd94d81e5bc3d1f68591701db5adb342f0d)
1 /*
2  * trace_output.c
3  *
4  * Copyright (C) 2008 Red Hat Inc, Steven Rostedt <srostedt@redhat.com>
5  *
6  */
7 
8 #include <linux/module.h>
9 #include <linux/mutex.h>
10 #include <linux/ftrace.h>
11 
12 #include "trace_output.h"
13 
14 /* must be a power of 2 */
15 #define EVENT_HASHSIZE	128
16 
17 DECLARE_RWSEM(trace_event_mutex);
18 
19 DEFINE_PER_CPU(struct trace_seq, ftrace_event_seq);
20 EXPORT_PER_CPU_SYMBOL(ftrace_event_seq);
21 
22 static struct hlist_head event_hash[EVENT_HASHSIZE] __read_mostly;
23 
24 static int next_event_type = __TRACE_LAST_TYPE + 1;
25 
26 void trace_print_seq(struct seq_file *m, struct trace_seq *s)
27 {
28 	int len = s->len >= PAGE_SIZE ? PAGE_SIZE - 1 : s->len;
29 
30 	s->buffer[len] = 0;
31 	seq_puts(m, s->buffer);
32 
33 	trace_seq_init(s);
34 }
35 
36 enum print_line_t trace_print_bprintk_msg_only(struct trace_iterator *iter)
37 {
38 	struct trace_seq *s = &iter->seq;
39 	struct trace_entry *entry = iter->ent;
40 	struct bprint_entry *field;
41 	int ret;
42 
43 	trace_assign_type(field, entry);
44 
45 	ret = trace_seq_bprintf(s, field->fmt, field->buf);
46 	if (!ret)
47 		return TRACE_TYPE_PARTIAL_LINE;
48 
49 	return TRACE_TYPE_HANDLED;
50 }
51 
52 enum print_line_t trace_print_printk_msg_only(struct trace_iterator *iter)
53 {
54 	struct trace_seq *s = &iter->seq;
55 	struct trace_entry *entry = iter->ent;
56 	struct print_entry *field;
57 	int ret;
58 
59 	trace_assign_type(field, entry);
60 
61 	ret = trace_seq_printf(s, "%s", field->buf);
62 	if (!ret)
63 		return TRACE_TYPE_PARTIAL_LINE;
64 
65 	return TRACE_TYPE_HANDLED;
66 }
67 
68 /**
69  * trace_seq_printf - sequence printing of trace information
70  * @s: trace sequence descriptor
71  * @fmt: printf format string
72  *
73  * The tracer may use either sequence operations or its own
74  * copy to user routines. To simplify formating of a trace
75  * trace_seq_printf is used to store strings into a special
76  * buffer (@s). Then the output may be either used by
77  * the sequencer or pulled into another buffer.
78  */
79 int
80 trace_seq_printf(struct trace_seq *s, const char *fmt, ...)
81 {
82 	int len = (PAGE_SIZE - 1) - s->len;
83 	va_list ap;
84 	int ret;
85 
86 	if (!len)
87 		return 0;
88 
89 	va_start(ap, fmt);
90 	ret = vsnprintf(s->buffer + s->len, len, fmt, ap);
91 	va_end(ap);
92 
93 	/* If we can't write it all, don't bother writing anything */
94 	if (ret >= len)
95 		return 0;
96 
97 	s->len += ret;
98 
99 	return len;
100 }
101 EXPORT_SYMBOL_GPL(trace_seq_printf);
102 
103 /**
104  * trace_seq_vprintf - sequence printing of trace information
105  * @s: trace sequence descriptor
106  * @fmt: printf format string
107  *
108  * The tracer may use either sequence operations or its own
109  * copy to user routines. To simplify formating of a trace
110  * trace_seq_printf is used to store strings into a special
111  * buffer (@s). Then the output may be either used by
112  * the sequencer or pulled into another buffer.
113  */
114 int
115 trace_seq_vprintf(struct trace_seq *s, const char *fmt, va_list args)
116 {
117 	int len = (PAGE_SIZE - 1) - s->len;
118 	int ret;
119 
120 	if (!len)
121 		return 0;
122 
123 	ret = vsnprintf(s->buffer + s->len, len, fmt, args);
124 
125 	/* If we can't write it all, don't bother writing anything */
126 	if (ret >= len)
127 		return 0;
128 
129 	s->len += ret;
130 
131 	return len;
132 }
133 EXPORT_SYMBOL_GPL(trace_seq_vprintf);
134 
135 int trace_seq_bprintf(struct trace_seq *s, const char *fmt, const u32 *binary)
136 {
137 	int len = (PAGE_SIZE - 1) - s->len;
138 	int ret;
139 
140 	if (!len)
141 		return 0;
142 
143 	ret = bstr_printf(s->buffer + s->len, len, fmt, binary);
144 
145 	/* If we can't write it all, don't bother writing anything */
146 	if (ret >= len)
147 		return 0;
148 
149 	s->len += ret;
150 
151 	return len;
152 }
153 
154 /**
155  * trace_seq_puts - trace sequence printing of simple string
156  * @s: trace sequence descriptor
157  * @str: simple string to record
158  *
159  * The tracer may use either the sequence operations or its own
160  * copy to user routines. This function records a simple string
161  * into a special buffer (@s) for later retrieval by a sequencer
162  * or other mechanism.
163  */
164 int trace_seq_puts(struct trace_seq *s, const char *str)
165 {
166 	int len = strlen(str);
167 
168 	if (len > ((PAGE_SIZE - 1) - s->len))
169 		return 0;
170 
171 	memcpy(s->buffer + s->len, str, len);
172 	s->len += len;
173 
174 	return len;
175 }
176 
177 int trace_seq_putc(struct trace_seq *s, unsigned char c)
178 {
179 	if (s->len >= (PAGE_SIZE - 1))
180 		return 0;
181 
182 	s->buffer[s->len++] = c;
183 
184 	return 1;
185 }
186 
187 int trace_seq_putmem(struct trace_seq *s, const void *mem, size_t len)
188 {
189 	if (len > ((PAGE_SIZE - 1) - s->len))
190 		return 0;
191 
192 	memcpy(s->buffer + s->len, mem, len);
193 	s->len += len;
194 
195 	return len;
196 }
197 
198 int trace_seq_putmem_hex(struct trace_seq *s, const void *mem, size_t len)
199 {
200 	unsigned char hex[HEX_CHARS];
201 	const unsigned char *data = mem;
202 	int i, j;
203 
204 #ifdef __BIG_ENDIAN
205 	for (i = 0, j = 0; i < len; i++) {
206 #else
207 	for (i = len-1, j = 0; i >= 0; i--) {
208 #endif
209 		hex[j++] = hex_asc_hi(data[i]);
210 		hex[j++] = hex_asc_lo(data[i]);
211 	}
212 	hex[j++] = ' ';
213 
214 	return trace_seq_putmem(s, hex, j);
215 }
216 
217 void *trace_seq_reserve(struct trace_seq *s, size_t len)
218 {
219 	void *ret;
220 
221 	if (len > ((PAGE_SIZE - 1) - s->len))
222 		return NULL;
223 
224 	ret = s->buffer + s->len;
225 	s->len += len;
226 
227 	return ret;
228 }
229 
230 int trace_seq_path(struct trace_seq *s, struct path *path)
231 {
232 	unsigned char *p;
233 
234 	if (s->len >= (PAGE_SIZE - 1))
235 		return 0;
236 	p = d_path(path, s->buffer + s->len, PAGE_SIZE - s->len);
237 	if (!IS_ERR(p)) {
238 		p = mangle_path(s->buffer + s->len, p, "\n");
239 		if (p) {
240 			s->len = p - s->buffer;
241 			return 1;
242 		}
243 	} else {
244 		s->buffer[s->len++] = '?';
245 		return 1;
246 	}
247 
248 	return 0;
249 }
250 
251 const char *
252 ftrace_print_flags_seq(struct trace_seq *p, const char *delim,
253 		       unsigned long flags,
254 		       const struct trace_print_flags *flag_array)
255 {
256 	unsigned long mask;
257 	const char *str;
258 	const char *ret = p->buffer + p->len;
259 	int i;
260 
261 	for (i = 0;  flag_array[i].name && flags; i++) {
262 
263 		mask = flag_array[i].mask;
264 		if ((flags & mask) != mask)
265 			continue;
266 
267 		str = flag_array[i].name;
268 		flags &= ~mask;
269 		if (p->len && delim)
270 			trace_seq_puts(p, delim);
271 		trace_seq_puts(p, str);
272 	}
273 
274 	/* check for left over flags */
275 	if (flags) {
276 		if (p->len && delim)
277 			trace_seq_puts(p, delim);
278 		trace_seq_printf(p, "0x%lx", flags);
279 	}
280 
281 	trace_seq_putc(p, 0);
282 
283 	return ret;
284 }
285 EXPORT_SYMBOL(ftrace_print_flags_seq);
286 
287 const char *
288 ftrace_print_symbols_seq(struct trace_seq *p, unsigned long val,
289 			 const struct trace_print_flags *symbol_array)
290 {
291 	int i;
292 	const char *ret = p->buffer + p->len;
293 
294 	for (i = 0;  symbol_array[i].name; i++) {
295 
296 		if (val != symbol_array[i].mask)
297 			continue;
298 
299 		trace_seq_puts(p, symbol_array[i].name);
300 		break;
301 	}
302 
303 	if (!p->len)
304 		trace_seq_printf(p, "0x%lx", val);
305 
306 	trace_seq_putc(p, 0);
307 
308 	return ret;
309 }
310 EXPORT_SYMBOL(ftrace_print_symbols_seq);
311 
312 #ifdef CONFIG_KRETPROBES
313 static inline const char *kretprobed(const char *name)
314 {
315 	static const char tramp_name[] = "kretprobe_trampoline";
316 	int size = sizeof(tramp_name);
317 
318 	if (strncmp(tramp_name, name, size) == 0)
319 		return "[unknown/kretprobe'd]";
320 	return name;
321 }
322 #else
323 static inline const char *kretprobed(const char *name)
324 {
325 	return name;
326 }
327 #endif /* CONFIG_KRETPROBES */
328 
329 static int
330 seq_print_sym_short(struct trace_seq *s, const char *fmt, unsigned long address)
331 {
332 #ifdef CONFIG_KALLSYMS
333 	char str[KSYM_SYMBOL_LEN];
334 	const char *name;
335 
336 	kallsyms_lookup(address, NULL, NULL, NULL, str);
337 
338 	name = kretprobed(str);
339 
340 	return trace_seq_printf(s, fmt, name);
341 #endif
342 	return 1;
343 }
344 
345 static int
346 seq_print_sym_offset(struct trace_seq *s, const char *fmt,
347 		     unsigned long address)
348 {
349 #ifdef CONFIG_KALLSYMS
350 	char str[KSYM_SYMBOL_LEN];
351 	const char *name;
352 
353 	sprint_symbol(str, address);
354 	name = kretprobed(str);
355 
356 	return trace_seq_printf(s, fmt, name);
357 #endif
358 	return 1;
359 }
360 
361 #ifndef CONFIG_64BIT
362 # define IP_FMT "%08lx"
363 #else
364 # define IP_FMT "%016lx"
365 #endif
366 
367 int seq_print_user_ip(struct trace_seq *s, struct mm_struct *mm,
368 		      unsigned long ip, unsigned long sym_flags)
369 {
370 	struct file *file = NULL;
371 	unsigned long vmstart = 0;
372 	int ret = 1;
373 
374 	if (mm) {
375 		const struct vm_area_struct *vma;
376 
377 		down_read(&mm->mmap_sem);
378 		vma = find_vma(mm, ip);
379 		if (vma) {
380 			file = vma->vm_file;
381 			vmstart = vma->vm_start;
382 		}
383 		if (file) {
384 			ret = trace_seq_path(s, &file->f_path);
385 			if (ret)
386 				ret = trace_seq_printf(s, "[+0x%lx]",
387 						       ip - vmstart);
388 		}
389 		up_read(&mm->mmap_sem);
390 	}
391 	if (ret && ((sym_flags & TRACE_ITER_SYM_ADDR) || !file))
392 		ret = trace_seq_printf(s, " <" IP_FMT ">", ip);
393 	return ret;
394 }
395 
396 int
397 seq_print_userip_objs(const struct userstack_entry *entry, struct trace_seq *s,
398 		      unsigned long sym_flags)
399 {
400 	struct mm_struct *mm = NULL;
401 	int ret = 1;
402 	unsigned int i;
403 
404 	if (trace_flags & TRACE_ITER_SYM_USEROBJ) {
405 		struct task_struct *task;
406 		/*
407 		 * we do the lookup on the thread group leader,
408 		 * since individual threads might have already quit!
409 		 */
410 		rcu_read_lock();
411 		task = find_task_by_vpid(entry->ent.tgid);
412 		if (task)
413 			mm = get_task_mm(task);
414 		rcu_read_unlock();
415 	}
416 
417 	for (i = 0; i < FTRACE_STACK_ENTRIES; i++) {
418 		unsigned long ip = entry->caller[i];
419 
420 		if (ip == ULONG_MAX || !ret)
421 			break;
422 		if (ret)
423 			ret = trace_seq_puts(s, " => ");
424 		if (!ip) {
425 			if (ret)
426 				ret = trace_seq_puts(s, "??");
427 			if (ret)
428 				ret = trace_seq_puts(s, "\n");
429 			continue;
430 		}
431 		if (!ret)
432 			break;
433 		if (ret)
434 			ret = seq_print_user_ip(s, mm, ip, sym_flags);
435 		ret = trace_seq_puts(s, "\n");
436 	}
437 
438 	if (mm)
439 		mmput(mm);
440 	return ret;
441 }
442 
443 int
444 seq_print_ip_sym(struct trace_seq *s, unsigned long ip, unsigned long sym_flags)
445 {
446 	int ret;
447 
448 	if (!ip)
449 		return trace_seq_printf(s, "0");
450 
451 	if (sym_flags & TRACE_ITER_SYM_OFFSET)
452 		ret = seq_print_sym_offset(s, "%s", ip);
453 	else
454 		ret = seq_print_sym_short(s, "%s", ip);
455 
456 	if (!ret)
457 		return 0;
458 
459 	if (sym_flags & TRACE_ITER_SYM_ADDR)
460 		ret = trace_seq_printf(s, " <" IP_FMT ">", ip);
461 	return ret;
462 }
463 
464 static int
465 lat_print_generic(struct trace_seq *s, struct trace_entry *entry, int cpu)
466 {
467 	int hardirq, softirq;
468 	char comm[TASK_COMM_LEN];
469 
470 	trace_find_cmdline(entry->pid, comm);
471 	hardirq = entry->flags & TRACE_FLAG_HARDIRQ;
472 	softirq = entry->flags & TRACE_FLAG_SOFTIRQ;
473 
474 	if (!trace_seq_printf(s, "%8.8s-%-5d %3d%c%c%c",
475 			      comm, entry->pid, cpu,
476 			      (entry->flags & TRACE_FLAG_IRQS_OFF) ? 'd' :
477 				(entry->flags & TRACE_FLAG_IRQS_NOSUPPORT) ?
478 				  'X' : '.',
479 			      (entry->flags & TRACE_FLAG_NEED_RESCHED) ?
480 				'N' : '.',
481 			      (hardirq && softirq) ? 'H' :
482 				hardirq ? 'h' : softirq ? 's' : '.'))
483 		return 0;
484 
485 	if (entry->preempt_count)
486 		return trace_seq_printf(s, "%x", entry->preempt_count);
487 	return trace_seq_puts(s, ".");
488 }
489 
490 static unsigned long preempt_mark_thresh = 100;
491 
492 static int
493 lat_print_timestamp(struct trace_seq *s, u64 abs_usecs,
494 		    unsigned long rel_usecs)
495 {
496 	return trace_seq_printf(s, " %4lldus%c: ", abs_usecs,
497 				rel_usecs > preempt_mark_thresh ? '!' :
498 				  rel_usecs > 1 ? '+' : ' ');
499 }
500 
501 int trace_print_context(struct trace_iterator *iter)
502 {
503 	struct trace_seq *s = &iter->seq;
504 	struct trace_entry *entry = iter->ent;
505 	unsigned long long t = ns2usecs(iter->ts);
506 	unsigned long usec_rem = do_div(t, USEC_PER_SEC);
507 	unsigned long secs = (unsigned long)t;
508 	char comm[TASK_COMM_LEN];
509 
510 	trace_find_cmdline(entry->pid, comm);
511 
512 	return trace_seq_printf(s, "%16s-%-5d [%03d] %5lu.%06lu: ",
513 				comm, entry->pid, iter->cpu, secs, usec_rem);
514 }
515 
516 int trace_print_lat_context(struct trace_iterator *iter)
517 {
518 	u64 next_ts;
519 	int ret;
520 	struct trace_seq *s = &iter->seq;
521 	struct trace_entry *entry = iter->ent,
522 			   *next_entry = trace_find_next_entry(iter, NULL,
523 							       &next_ts);
524 	unsigned long verbose = (trace_flags & TRACE_ITER_VERBOSE);
525 	unsigned long abs_usecs = ns2usecs(iter->ts - iter->tr->time_start);
526 	unsigned long rel_usecs;
527 
528 	if (!next_entry)
529 		next_ts = iter->ts;
530 	rel_usecs = ns2usecs(next_ts - iter->ts);
531 
532 	if (verbose) {
533 		char comm[TASK_COMM_LEN];
534 
535 		trace_find_cmdline(entry->pid, comm);
536 
537 		ret = trace_seq_printf(s, "%16s %5d %3d %d %08x %08lx [%08llx]"
538 				       " %ld.%03ldms (+%ld.%03ldms): ", comm,
539 				       entry->pid, iter->cpu, entry->flags,
540 				       entry->preempt_count, iter->idx,
541 				       ns2usecs(iter->ts),
542 				       abs_usecs / USEC_PER_MSEC,
543 				       abs_usecs % USEC_PER_MSEC,
544 				       rel_usecs / USEC_PER_MSEC,
545 				       rel_usecs % USEC_PER_MSEC);
546 	} else {
547 		ret = lat_print_generic(s, entry, iter->cpu);
548 		if (ret)
549 			ret = lat_print_timestamp(s, abs_usecs, rel_usecs);
550 	}
551 
552 	return ret;
553 }
554 
555 static const char state_to_char[] = TASK_STATE_TO_CHAR_STR;
556 
557 static int task_state_char(unsigned long state)
558 {
559 	int bit = state ? __ffs(state) + 1 : 0;
560 
561 	return bit < sizeof(state_to_char) - 1 ? state_to_char[bit] : '?';
562 }
563 
564 /**
565  * ftrace_find_event - find a registered event
566  * @type: the type of event to look for
567  *
568  * Returns an event of type @type otherwise NULL
569  * Called with trace_event_read_lock() held.
570  */
571 struct trace_event *ftrace_find_event(int type)
572 {
573 	struct trace_event *event;
574 	struct hlist_node *n;
575 	unsigned key;
576 
577 	key = type & (EVENT_HASHSIZE - 1);
578 
579 	hlist_for_each_entry(event, n, &event_hash[key], node) {
580 		if (event->type == type)
581 			return event;
582 	}
583 
584 	return NULL;
585 }
586 
587 static LIST_HEAD(ftrace_event_list);
588 
589 static int trace_search_list(struct list_head **list)
590 {
591 	struct trace_event *e;
592 	int last = __TRACE_LAST_TYPE;
593 
594 	if (list_empty(&ftrace_event_list)) {
595 		*list = &ftrace_event_list;
596 		return last + 1;
597 	}
598 
599 	/*
600 	 * We used up all possible max events,
601 	 * lets see if somebody freed one.
602 	 */
603 	list_for_each_entry(e, &ftrace_event_list, list) {
604 		if (e->type != last + 1)
605 			break;
606 		last++;
607 	}
608 
609 	/* Did we used up all 65 thousand events??? */
610 	if ((last + 1) > FTRACE_MAX_EVENT)
611 		return 0;
612 
613 	*list = &e->list;
614 	return last + 1;
615 }
616 
617 void trace_event_read_lock(void)
618 {
619 	down_read(&trace_event_mutex);
620 }
621 
622 void trace_event_read_unlock(void)
623 {
624 	up_read(&trace_event_mutex);
625 }
626 
627 /**
628  * register_ftrace_event - register output for an event type
629  * @event: the event type to register
630  *
631  * Event types are stored in a hash and this hash is used to
632  * find a way to print an event. If the @event->type is set
633  * then it will use that type, otherwise it will assign a
634  * type to use.
635  *
636  * If you assign your own type, please make sure it is added
637  * to the trace_type enum in trace.h, to avoid collisions
638  * with the dynamic types.
639  *
640  * Returns the event type number or zero on error.
641  */
642 int register_ftrace_event(struct trace_event *event)
643 {
644 	unsigned key;
645 	int ret = 0;
646 
647 	down_write(&trace_event_mutex);
648 
649 	if (WARN_ON(!event))
650 		goto out;
651 
652 	INIT_LIST_HEAD(&event->list);
653 
654 	if (!event->type) {
655 		struct list_head *list = NULL;
656 
657 		if (next_event_type > FTRACE_MAX_EVENT) {
658 
659 			event->type = trace_search_list(&list);
660 			if (!event->type)
661 				goto out;
662 
663 		} else {
664 
665 			event->type = next_event_type++;
666 			list = &ftrace_event_list;
667 		}
668 
669 		if (WARN_ON(ftrace_find_event(event->type)))
670 			goto out;
671 
672 		list_add_tail(&event->list, list);
673 
674 	} else if (event->type > __TRACE_LAST_TYPE) {
675 		printk(KERN_WARNING "Need to add type to trace.h\n");
676 		WARN_ON(1);
677 		goto out;
678 	} else {
679 		/* Is this event already used */
680 		if (ftrace_find_event(event->type))
681 			goto out;
682 	}
683 
684 	if (event->trace == NULL)
685 		event->trace = trace_nop_print;
686 	if (event->raw == NULL)
687 		event->raw = trace_nop_print;
688 	if (event->hex == NULL)
689 		event->hex = trace_nop_print;
690 	if (event->binary == NULL)
691 		event->binary = trace_nop_print;
692 
693 	key = event->type & (EVENT_HASHSIZE - 1);
694 
695 	hlist_add_head(&event->node, &event_hash[key]);
696 
697 	ret = event->type;
698  out:
699 	up_write(&trace_event_mutex);
700 
701 	return ret;
702 }
703 EXPORT_SYMBOL_GPL(register_ftrace_event);
704 
705 /*
706  * Used by module code with the trace_event_mutex held for write.
707  */
708 int __unregister_ftrace_event(struct trace_event *event)
709 {
710 	hlist_del(&event->node);
711 	list_del(&event->list);
712 	return 0;
713 }
714 
715 /**
716  * unregister_ftrace_event - remove a no longer used event
717  * @event: the event to remove
718  */
719 int unregister_ftrace_event(struct trace_event *event)
720 {
721 	down_write(&trace_event_mutex);
722 	__unregister_ftrace_event(event);
723 	up_write(&trace_event_mutex);
724 
725 	return 0;
726 }
727 EXPORT_SYMBOL_GPL(unregister_ftrace_event);
728 
729 /*
730  * Standard events
731  */
732 
733 enum print_line_t trace_nop_print(struct trace_iterator *iter, int flags)
734 {
735 	return TRACE_TYPE_HANDLED;
736 }
737 
738 /* TRACE_FN */
739 static enum print_line_t trace_fn_trace(struct trace_iterator *iter, int flags)
740 {
741 	struct ftrace_entry *field;
742 	struct trace_seq *s = &iter->seq;
743 
744 	trace_assign_type(field, iter->ent);
745 
746 	if (!seq_print_ip_sym(s, field->ip, flags))
747 		goto partial;
748 
749 	if ((flags & TRACE_ITER_PRINT_PARENT) && field->parent_ip) {
750 		if (!trace_seq_printf(s, " <-"))
751 			goto partial;
752 		if (!seq_print_ip_sym(s,
753 				      field->parent_ip,
754 				      flags))
755 			goto partial;
756 	}
757 	if (!trace_seq_printf(s, "\n"))
758 		goto partial;
759 
760 	return TRACE_TYPE_HANDLED;
761 
762  partial:
763 	return TRACE_TYPE_PARTIAL_LINE;
764 }
765 
766 static enum print_line_t trace_fn_raw(struct trace_iterator *iter, int flags)
767 {
768 	struct ftrace_entry *field;
769 
770 	trace_assign_type(field, iter->ent);
771 
772 	if (!trace_seq_printf(&iter->seq, "%lx %lx\n",
773 			      field->ip,
774 			      field->parent_ip))
775 		return TRACE_TYPE_PARTIAL_LINE;
776 
777 	return TRACE_TYPE_HANDLED;
778 }
779 
780 static enum print_line_t trace_fn_hex(struct trace_iterator *iter, int flags)
781 {
782 	struct ftrace_entry *field;
783 	struct trace_seq *s = &iter->seq;
784 
785 	trace_assign_type(field, iter->ent);
786 
787 	SEQ_PUT_HEX_FIELD_RET(s, field->ip);
788 	SEQ_PUT_HEX_FIELD_RET(s, field->parent_ip);
789 
790 	return TRACE_TYPE_HANDLED;
791 }
792 
793 static enum print_line_t trace_fn_bin(struct trace_iterator *iter, int flags)
794 {
795 	struct ftrace_entry *field;
796 	struct trace_seq *s = &iter->seq;
797 
798 	trace_assign_type(field, iter->ent);
799 
800 	SEQ_PUT_FIELD_RET(s, field->ip);
801 	SEQ_PUT_FIELD_RET(s, field->parent_ip);
802 
803 	return TRACE_TYPE_HANDLED;
804 }
805 
806 static struct trace_event trace_fn_event = {
807 	.type		= TRACE_FN,
808 	.trace		= trace_fn_trace,
809 	.raw		= trace_fn_raw,
810 	.hex		= trace_fn_hex,
811 	.binary		= trace_fn_bin,
812 };
813 
814 /* TRACE_CTX an TRACE_WAKE */
815 static enum print_line_t trace_ctxwake_print(struct trace_iterator *iter,
816 					     char *delim)
817 {
818 	struct ctx_switch_entry *field;
819 	char comm[TASK_COMM_LEN];
820 	int S, T;
821 
822 
823 	trace_assign_type(field, iter->ent);
824 
825 	T = task_state_char(field->next_state);
826 	S = task_state_char(field->prev_state);
827 	trace_find_cmdline(field->next_pid, comm);
828 	if (!trace_seq_printf(&iter->seq,
829 			      " %5d:%3d:%c %s [%03d] %5d:%3d:%c %s\n",
830 			      field->prev_pid,
831 			      field->prev_prio,
832 			      S, delim,
833 			      field->next_cpu,
834 			      field->next_pid,
835 			      field->next_prio,
836 			      T, comm))
837 		return TRACE_TYPE_PARTIAL_LINE;
838 
839 	return TRACE_TYPE_HANDLED;
840 }
841 
842 static enum print_line_t trace_ctx_print(struct trace_iterator *iter, int flags)
843 {
844 	return trace_ctxwake_print(iter, "==>");
845 }
846 
847 static enum print_line_t trace_wake_print(struct trace_iterator *iter,
848 					  int flags)
849 {
850 	return trace_ctxwake_print(iter, "  +");
851 }
852 
853 static int trace_ctxwake_raw(struct trace_iterator *iter, char S)
854 {
855 	struct ctx_switch_entry *field;
856 	int T;
857 
858 	trace_assign_type(field, iter->ent);
859 
860 	if (!S)
861 		task_state_char(field->prev_state);
862 	T = task_state_char(field->next_state);
863 	if (!trace_seq_printf(&iter->seq, "%d %d %c %d %d %d %c\n",
864 			      field->prev_pid,
865 			      field->prev_prio,
866 			      S,
867 			      field->next_cpu,
868 			      field->next_pid,
869 			      field->next_prio,
870 			      T))
871 		return TRACE_TYPE_PARTIAL_LINE;
872 
873 	return TRACE_TYPE_HANDLED;
874 }
875 
876 static enum print_line_t trace_ctx_raw(struct trace_iterator *iter, int flags)
877 {
878 	return trace_ctxwake_raw(iter, 0);
879 }
880 
881 static enum print_line_t trace_wake_raw(struct trace_iterator *iter, int flags)
882 {
883 	return trace_ctxwake_raw(iter, '+');
884 }
885 
886 
887 static int trace_ctxwake_hex(struct trace_iterator *iter, char S)
888 {
889 	struct ctx_switch_entry *field;
890 	struct trace_seq *s = &iter->seq;
891 	int T;
892 
893 	trace_assign_type(field, iter->ent);
894 
895 	if (!S)
896 		task_state_char(field->prev_state);
897 	T = task_state_char(field->next_state);
898 
899 	SEQ_PUT_HEX_FIELD_RET(s, field->prev_pid);
900 	SEQ_PUT_HEX_FIELD_RET(s, field->prev_prio);
901 	SEQ_PUT_HEX_FIELD_RET(s, S);
902 	SEQ_PUT_HEX_FIELD_RET(s, field->next_cpu);
903 	SEQ_PUT_HEX_FIELD_RET(s, field->next_pid);
904 	SEQ_PUT_HEX_FIELD_RET(s, field->next_prio);
905 	SEQ_PUT_HEX_FIELD_RET(s, T);
906 
907 	return TRACE_TYPE_HANDLED;
908 }
909 
910 static enum print_line_t trace_ctx_hex(struct trace_iterator *iter, int flags)
911 {
912 	return trace_ctxwake_hex(iter, 0);
913 }
914 
915 static enum print_line_t trace_wake_hex(struct trace_iterator *iter, int flags)
916 {
917 	return trace_ctxwake_hex(iter, '+');
918 }
919 
920 static enum print_line_t trace_ctxwake_bin(struct trace_iterator *iter,
921 					   int flags)
922 {
923 	struct ctx_switch_entry *field;
924 	struct trace_seq *s = &iter->seq;
925 
926 	trace_assign_type(field, iter->ent);
927 
928 	SEQ_PUT_FIELD_RET(s, field->prev_pid);
929 	SEQ_PUT_FIELD_RET(s, field->prev_prio);
930 	SEQ_PUT_FIELD_RET(s, field->prev_state);
931 	SEQ_PUT_FIELD_RET(s, field->next_pid);
932 	SEQ_PUT_FIELD_RET(s, field->next_prio);
933 	SEQ_PUT_FIELD_RET(s, field->next_state);
934 
935 	return TRACE_TYPE_HANDLED;
936 }
937 
938 static struct trace_event trace_ctx_event = {
939 	.type		= TRACE_CTX,
940 	.trace		= trace_ctx_print,
941 	.raw		= trace_ctx_raw,
942 	.hex		= trace_ctx_hex,
943 	.binary		= trace_ctxwake_bin,
944 };
945 
946 static struct trace_event trace_wake_event = {
947 	.type		= TRACE_WAKE,
948 	.trace		= trace_wake_print,
949 	.raw		= trace_wake_raw,
950 	.hex		= trace_wake_hex,
951 	.binary		= trace_ctxwake_bin,
952 };
953 
954 /* TRACE_SPECIAL */
955 static enum print_line_t trace_special_print(struct trace_iterator *iter,
956 					     int flags)
957 {
958 	struct special_entry *field;
959 
960 	trace_assign_type(field, iter->ent);
961 
962 	if (!trace_seq_printf(&iter->seq, "# %ld %ld %ld\n",
963 			      field->arg1,
964 			      field->arg2,
965 			      field->arg3))
966 		return TRACE_TYPE_PARTIAL_LINE;
967 
968 	return TRACE_TYPE_HANDLED;
969 }
970 
971 static enum print_line_t trace_special_hex(struct trace_iterator *iter,
972 					   int flags)
973 {
974 	struct special_entry *field;
975 	struct trace_seq *s = &iter->seq;
976 
977 	trace_assign_type(field, iter->ent);
978 
979 	SEQ_PUT_HEX_FIELD_RET(s, field->arg1);
980 	SEQ_PUT_HEX_FIELD_RET(s, field->arg2);
981 	SEQ_PUT_HEX_FIELD_RET(s, field->arg3);
982 
983 	return TRACE_TYPE_HANDLED;
984 }
985 
986 static enum print_line_t trace_special_bin(struct trace_iterator *iter,
987 					   int flags)
988 {
989 	struct special_entry *field;
990 	struct trace_seq *s = &iter->seq;
991 
992 	trace_assign_type(field, iter->ent);
993 
994 	SEQ_PUT_FIELD_RET(s, field->arg1);
995 	SEQ_PUT_FIELD_RET(s, field->arg2);
996 	SEQ_PUT_FIELD_RET(s, field->arg3);
997 
998 	return TRACE_TYPE_HANDLED;
999 }
1000 
1001 static struct trace_event trace_special_event = {
1002 	.type		= TRACE_SPECIAL,
1003 	.trace		= trace_special_print,
1004 	.raw		= trace_special_print,
1005 	.hex		= trace_special_hex,
1006 	.binary		= trace_special_bin,
1007 };
1008 
1009 /* TRACE_STACK */
1010 
1011 static enum print_line_t trace_stack_print(struct trace_iterator *iter,
1012 					   int flags)
1013 {
1014 	struct stack_entry *field;
1015 	struct trace_seq *s = &iter->seq;
1016 	int i;
1017 
1018 	trace_assign_type(field, iter->ent);
1019 
1020 	if (!trace_seq_puts(s, "<stack trace>\n"))
1021 		goto partial;
1022 	for (i = 0; i < FTRACE_STACK_ENTRIES; i++) {
1023 		if (!field->caller[i] || (field->caller[i] == ULONG_MAX))
1024 			break;
1025 		if (!trace_seq_puts(s, " => "))
1026 			goto partial;
1027 
1028 		if (!seq_print_ip_sym(s, field->caller[i], flags))
1029 			goto partial;
1030 		if (!trace_seq_puts(s, "\n"))
1031 			goto partial;
1032 	}
1033 
1034 	return TRACE_TYPE_HANDLED;
1035 
1036  partial:
1037 	return TRACE_TYPE_PARTIAL_LINE;
1038 }
1039 
1040 static struct trace_event trace_stack_event = {
1041 	.type		= TRACE_STACK,
1042 	.trace		= trace_stack_print,
1043 	.raw		= trace_special_print,
1044 	.hex		= trace_special_hex,
1045 	.binary		= trace_special_bin,
1046 };
1047 
1048 /* TRACE_USER_STACK */
1049 static enum print_line_t trace_user_stack_print(struct trace_iterator *iter,
1050 						int flags)
1051 {
1052 	struct userstack_entry *field;
1053 	struct trace_seq *s = &iter->seq;
1054 
1055 	trace_assign_type(field, iter->ent);
1056 
1057 	if (!trace_seq_puts(s, "<user stack trace>\n"))
1058 		goto partial;
1059 
1060 	if (!seq_print_userip_objs(field, s, flags))
1061 		goto partial;
1062 
1063 	return TRACE_TYPE_HANDLED;
1064 
1065  partial:
1066 	return TRACE_TYPE_PARTIAL_LINE;
1067 }
1068 
1069 static struct trace_event trace_user_stack_event = {
1070 	.type		= TRACE_USER_STACK,
1071 	.trace		= trace_user_stack_print,
1072 	.raw		= trace_special_print,
1073 	.hex		= trace_special_hex,
1074 	.binary		= trace_special_bin,
1075 };
1076 
1077 /* TRACE_BPRINT */
1078 static enum print_line_t
1079 trace_bprint_print(struct trace_iterator *iter, int flags)
1080 {
1081 	struct trace_entry *entry = iter->ent;
1082 	struct trace_seq *s = &iter->seq;
1083 	struct bprint_entry *field;
1084 
1085 	trace_assign_type(field, entry);
1086 
1087 	if (!seq_print_ip_sym(s, field->ip, flags))
1088 		goto partial;
1089 
1090 	if (!trace_seq_puts(s, ": "))
1091 		goto partial;
1092 
1093 	if (!trace_seq_bprintf(s, field->fmt, field->buf))
1094 		goto partial;
1095 
1096 	return TRACE_TYPE_HANDLED;
1097 
1098  partial:
1099 	return TRACE_TYPE_PARTIAL_LINE;
1100 }
1101 
1102 
1103 static enum print_line_t
1104 trace_bprint_raw(struct trace_iterator *iter, int flags)
1105 {
1106 	struct bprint_entry *field;
1107 	struct trace_seq *s = &iter->seq;
1108 
1109 	trace_assign_type(field, iter->ent);
1110 
1111 	if (!trace_seq_printf(s, ": %lx : ", field->ip))
1112 		goto partial;
1113 
1114 	if (!trace_seq_bprintf(s, field->fmt, field->buf))
1115 		goto partial;
1116 
1117 	return TRACE_TYPE_HANDLED;
1118 
1119  partial:
1120 	return TRACE_TYPE_PARTIAL_LINE;
1121 }
1122 
1123 
1124 static struct trace_event trace_bprint_event = {
1125 	.type		= TRACE_BPRINT,
1126 	.trace		= trace_bprint_print,
1127 	.raw		= trace_bprint_raw,
1128 };
1129 
1130 /* TRACE_PRINT */
1131 static enum print_line_t trace_print_print(struct trace_iterator *iter,
1132 					   int flags)
1133 {
1134 	struct print_entry *field;
1135 	struct trace_seq *s = &iter->seq;
1136 
1137 	trace_assign_type(field, iter->ent);
1138 
1139 	if (!seq_print_ip_sym(s, field->ip, flags))
1140 		goto partial;
1141 
1142 	if (!trace_seq_printf(s, ": %s", field->buf))
1143 		goto partial;
1144 
1145 	return TRACE_TYPE_HANDLED;
1146 
1147  partial:
1148 	return TRACE_TYPE_PARTIAL_LINE;
1149 }
1150 
1151 static enum print_line_t trace_print_raw(struct trace_iterator *iter, int flags)
1152 {
1153 	struct print_entry *field;
1154 
1155 	trace_assign_type(field, iter->ent);
1156 
1157 	if (!trace_seq_printf(&iter->seq, "# %lx %s", field->ip, field->buf))
1158 		goto partial;
1159 
1160 	return TRACE_TYPE_HANDLED;
1161 
1162  partial:
1163 	return TRACE_TYPE_PARTIAL_LINE;
1164 }
1165 
1166 static struct trace_event trace_print_event = {
1167 	.type	 	= TRACE_PRINT,
1168 	.trace		= trace_print_print,
1169 	.raw		= trace_print_raw,
1170 };
1171 
1172 
1173 static struct trace_event *events[] __initdata = {
1174 	&trace_fn_event,
1175 	&trace_ctx_event,
1176 	&trace_wake_event,
1177 	&trace_special_event,
1178 	&trace_stack_event,
1179 	&trace_user_stack_event,
1180 	&trace_bprint_event,
1181 	&trace_print_event,
1182 	NULL
1183 };
1184 
1185 __init static int init_events(void)
1186 {
1187 	struct trace_event *event;
1188 	int i, ret;
1189 
1190 	for (i = 0; events[i]; i++) {
1191 		event = events[i];
1192 
1193 		ret = register_ftrace_event(event);
1194 		if (!ret) {
1195 			printk(KERN_WARNING "event %d failed to register\n",
1196 			       event->type);
1197 			WARN_ON_ONCE(1);
1198 		}
1199 	}
1200 
1201 	return 0;
1202 }
1203 device_initcall(init_events);
1204