Merge branch 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1...
[pandora-kernel.git] / kernel / trace / trace_output.c
1 /*
2  * trace_output.c
3  *
4  * Copyright (C) 2008 Red Hat Inc, Steven Rostedt <srostedt@redhat.com>
5  *
6  */
7
8 #include <linux/module.h>
9 #include <linux/mutex.h>
10 #include <linux/ftrace.h>
11
12 #include "trace_output.h"
13
14 /* must be a power of 2 */
15 #define EVENT_HASHSIZE  128
16
17 DECLARE_RWSEM(trace_event_mutex);
18
19 static struct hlist_head event_hash[EVENT_HASHSIZE] __read_mostly;
20
21 static int next_event_type = __TRACE_LAST_TYPE + 1;
22
23 int trace_print_seq(struct seq_file *m, struct trace_seq *s)
24 {
25         int len = s->len >= PAGE_SIZE ? PAGE_SIZE - 1 : s->len;
26         int ret;
27
28         ret = seq_write(m, s->buffer, len);
29
30         /*
31          * Only reset this buffer if we successfully wrote to the
32          * seq_file buffer.
33          */
34         if (!ret)
35                 trace_seq_init(s);
36
37         return ret;
38 }
39
40 enum print_line_t trace_print_bprintk_msg_only(struct trace_iterator *iter)
41 {
42         struct trace_seq *s = &iter->seq;
43         struct trace_entry *entry = iter->ent;
44         struct bprint_entry *field;
45         int ret;
46
47         trace_assign_type(field, entry);
48
49         ret = trace_seq_bprintf(s, field->fmt, field->buf);
50         if (!ret)
51                 return TRACE_TYPE_PARTIAL_LINE;
52
53         return TRACE_TYPE_HANDLED;
54 }
55
56 enum print_line_t trace_print_printk_msg_only(struct trace_iterator *iter)
57 {
58         struct trace_seq *s = &iter->seq;
59         struct trace_entry *entry = iter->ent;
60         struct print_entry *field;
61         int ret;
62
63         trace_assign_type(field, entry);
64
65         ret = trace_seq_printf(s, "%s", field->buf);
66         if (!ret)
67                 return TRACE_TYPE_PARTIAL_LINE;
68
69         return TRACE_TYPE_HANDLED;
70 }
71
72 /**
73  * trace_seq_printf - sequence printing of trace information
74  * @s: trace sequence descriptor
75  * @fmt: printf format string
76  *
77  * It returns 0 if the trace oversizes the buffer's free
78  * space, 1 otherwise.
79  *
80  * The tracer may use either sequence operations or its own
81  * copy to user routines. To simplify formating of a trace
82  * trace_seq_printf is used to store strings into a special
83  * buffer (@s). Then the output may be either used by
84  * the sequencer or pulled into another buffer.
85  */
86 int
87 trace_seq_printf(struct trace_seq *s, const char *fmt, ...)
88 {
89         int len = (PAGE_SIZE - 1) - s->len;
90         va_list ap;
91         int ret;
92
93         if (s->full || !len)
94                 return 0;
95
96         va_start(ap, fmt);
97         ret = vsnprintf(s->buffer + s->len, len, fmt, ap);
98         va_end(ap);
99
100         /* If we can't write it all, don't bother writing anything */
101         if (ret >= len) {
102                 s->full = 1;
103                 return 0;
104         }
105
106         s->len += ret;
107
108         return 1;
109 }
110 EXPORT_SYMBOL_GPL(trace_seq_printf);
111
112 /**
113  * trace_seq_vprintf - sequence printing of trace information
114  * @s: trace sequence descriptor
115  * @fmt: printf format string
116  *
117  * The tracer may use either sequence operations or its own
118  * copy to user routines. To simplify formating of a trace
119  * trace_seq_printf is used to store strings into a special
120  * buffer (@s). Then the output may be either used by
121  * the sequencer or pulled into another buffer.
122  */
123 int
124 trace_seq_vprintf(struct trace_seq *s, const char *fmt, va_list args)
125 {
126         int len = (PAGE_SIZE - 1) - s->len;
127         int ret;
128
129         if (s->full || !len)
130                 return 0;
131
132         ret = vsnprintf(s->buffer + s->len, len, fmt, args);
133
134         /* If we can't write it all, don't bother writing anything */
135         if (ret >= len) {
136                 s->full = 1;
137                 return 0;
138         }
139
140         s->len += ret;
141
142         return len;
143 }
144 EXPORT_SYMBOL_GPL(trace_seq_vprintf);
145
146 int trace_seq_bprintf(struct trace_seq *s, const char *fmt, const u32 *binary)
147 {
148         int len = (PAGE_SIZE - 1) - s->len;
149         int ret;
150
151         if (s->full || !len)
152                 return 0;
153
154         ret = bstr_printf(s->buffer + s->len, len, fmt, binary);
155
156         /* If we can't write it all, don't bother writing anything */
157         if (ret >= len) {
158                 s->full = 1;
159                 return 0;
160         }
161
162         s->len += ret;
163
164         return len;
165 }
166
167 /**
168  * trace_seq_puts - trace sequence printing of simple string
169  * @s: trace sequence descriptor
170  * @str: simple string to record
171  *
172  * The tracer may use either the sequence operations or its own
173  * copy to user routines. This function records a simple string
174  * into a special buffer (@s) for later retrieval by a sequencer
175  * or other mechanism.
176  */
177 int trace_seq_puts(struct trace_seq *s, const char *str)
178 {
179         int len = strlen(str);
180
181         if (s->full)
182                 return 0;
183
184         if (len > ((PAGE_SIZE - 1) - s->len)) {
185                 s->full = 1;
186                 return 0;
187         }
188
189         memcpy(s->buffer + s->len, str, len);
190         s->len += len;
191
192         return len;
193 }
194
195 int trace_seq_putc(struct trace_seq *s, unsigned char c)
196 {
197         if (s->full)
198                 return 0;
199
200         if (s->len >= (PAGE_SIZE - 1)) {
201                 s->full = 1;
202                 return 0;
203         }
204
205         s->buffer[s->len++] = c;
206
207         return 1;
208 }
209 EXPORT_SYMBOL(trace_seq_putc);
210
211 int trace_seq_putmem(struct trace_seq *s, const void *mem, size_t len)
212 {
213         if (s->full)
214                 return 0;
215
216         if (len > ((PAGE_SIZE - 1) - s->len)) {
217                 s->full = 1;
218                 return 0;
219         }
220
221         memcpy(s->buffer + s->len, mem, len);
222         s->len += len;
223
224         return len;
225 }
226
227 int trace_seq_putmem_hex(struct trace_seq *s, const void *mem, size_t len)
228 {
229         unsigned char hex[HEX_CHARS];
230         const unsigned char *data = mem;
231         int i, j;
232
233         if (s->full)
234                 return 0;
235
236 #ifdef __BIG_ENDIAN
237         for (i = 0, j = 0; i < len; i++) {
238 #else
239         for (i = len-1, j = 0; i >= 0; i--) {
240 #endif
241                 hex[j++] = hex_asc_hi(data[i]);
242                 hex[j++] = hex_asc_lo(data[i]);
243         }
244         hex[j++] = ' ';
245
246         return trace_seq_putmem(s, hex, j);
247 }
248
249 void *trace_seq_reserve(struct trace_seq *s, size_t len)
250 {
251         void *ret;
252
253         if (s->full)
254                 return NULL;
255
256         if (len > ((PAGE_SIZE - 1) - s->len)) {
257                 s->full = 1;
258                 return NULL;
259         }
260
261         ret = s->buffer + s->len;
262         s->len += len;
263
264         return ret;
265 }
266
267 int trace_seq_path(struct trace_seq *s, struct path *path)
268 {
269         unsigned char *p;
270
271         if (s->full)
272                 return 0;
273
274         if (s->len >= (PAGE_SIZE - 1)) {
275                 s->full = 1;
276                 return 0;
277         }
278
279         p = d_path(path, s->buffer + s->len, PAGE_SIZE - s->len);
280         if (!IS_ERR(p)) {
281                 p = mangle_path(s->buffer + s->len, p, "\n");
282                 if (p) {
283                         s->len = p - s->buffer;
284                         return 1;
285                 }
286         } else {
287                 s->buffer[s->len++] = '?';
288                 return 1;
289         }
290
291         s->full = 1;
292         return 0;
293 }
294
295 const char *
296 ftrace_print_flags_seq(struct trace_seq *p, const char *delim,
297                        unsigned long flags,
298                        const struct trace_print_flags *flag_array)
299 {
300         unsigned long mask;
301         const char *str;
302         const char *ret = p->buffer + p->len;
303         int i;
304
305         for (i = 0;  flag_array[i].name && flags; i++) {
306
307                 mask = flag_array[i].mask;
308                 if ((flags & mask) != mask)
309                         continue;
310
311                 str = flag_array[i].name;
312                 flags &= ~mask;
313                 if (p->len && delim)
314                         trace_seq_puts(p, delim);
315                 trace_seq_puts(p, str);
316         }
317
318         /* check for left over flags */
319         if (flags) {
320                 if (p->len && delim)
321                         trace_seq_puts(p, delim);
322                 trace_seq_printf(p, "0x%lx", flags);
323         }
324
325         trace_seq_putc(p, 0);
326
327         return ret;
328 }
329 EXPORT_SYMBOL(ftrace_print_flags_seq);
330
331 const char *
332 ftrace_print_symbols_seq(struct trace_seq *p, unsigned long val,
333                          const struct trace_print_flags *symbol_array)
334 {
335         int i;
336         const char *ret = p->buffer + p->len;
337
338         for (i = 0;  symbol_array[i].name; i++) {
339
340                 if (val != symbol_array[i].mask)
341                         continue;
342
343                 trace_seq_puts(p, symbol_array[i].name);
344                 break;
345         }
346
347         if (!p->len)
348                 trace_seq_printf(p, "0x%lx", val);
349                 
350         trace_seq_putc(p, 0);
351
352         return ret;
353 }
354 EXPORT_SYMBOL(ftrace_print_symbols_seq);
355
356 #if BITS_PER_LONG == 32
357 const char *
358 ftrace_print_symbols_seq_u64(struct trace_seq *p, unsigned long long val,
359                          const struct trace_print_flags_u64 *symbol_array)
360 {
361         int i;
362         const char *ret = p->buffer + p->len;
363
364         for (i = 0;  symbol_array[i].name; i++) {
365
366                 if (val != symbol_array[i].mask)
367                         continue;
368
369                 trace_seq_puts(p, symbol_array[i].name);
370                 break;
371         }
372
373         if (!p->len)
374                 trace_seq_printf(p, "0x%llx", val);
375
376         trace_seq_putc(p, 0);
377
378         return ret;
379 }
380 EXPORT_SYMBOL(ftrace_print_symbols_seq_u64);
381 #endif
382
383 const char *
384 ftrace_print_hex_seq(struct trace_seq *p, const unsigned char *buf, int buf_len)
385 {
386         int i;
387         const char *ret = p->buffer + p->len;
388
389         for (i = 0; i < buf_len; i++)
390                 trace_seq_printf(p, "%s%2.2x", i == 0 ? "" : " ", buf[i]);
391
392         trace_seq_putc(p, 0);
393
394         return ret;
395 }
396 EXPORT_SYMBOL(ftrace_print_hex_seq);
397
398 #ifdef CONFIG_KRETPROBES
399 static inline const char *kretprobed(const char *name)
400 {
401         static const char tramp_name[] = "kretprobe_trampoline";
402         int size = sizeof(tramp_name);
403
404         if (strncmp(tramp_name, name, size) == 0)
405                 return "[unknown/kretprobe'd]";
406         return name;
407 }
408 #else
409 static inline const char *kretprobed(const char *name)
410 {
411         return name;
412 }
413 #endif /* CONFIG_KRETPROBES */
414
415 static int
416 seq_print_sym_short(struct trace_seq *s, const char *fmt, unsigned long address)
417 {
418 #ifdef CONFIG_KALLSYMS
419         char str[KSYM_SYMBOL_LEN];
420         const char *name;
421
422         kallsyms_lookup(address, NULL, NULL, NULL, str);
423
424         name = kretprobed(str);
425
426         return trace_seq_printf(s, fmt, name);
427 #endif
428         return 1;
429 }
430
431 static int
432 seq_print_sym_offset(struct trace_seq *s, const char *fmt,
433                      unsigned long address)
434 {
435 #ifdef CONFIG_KALLSYMS
436         char str[KSYM_SYMBOL_LEN];
437         const char *name;
438
439         sprint_symbol(str, address);
440         name = kretprobed(str);
441
442         return trace_seq_printf(s, fmt, name);
443 #endif
444         return 1;
445 }
446
447 #ifndef CONFIG_64BIT
448 # define IP_FMT "%08lx"
449 #else
450 # define IP_FMT "%016lx"
451 #endif
452
453 int seq_print_user_ip(struct trace_seq *s, struct mm_struct *mm,
454                       unsigned long ip, unsigned long sym_flags)
455 {
456         struct file *file = NULL;
457         unsigned long vmstart = 0;
458         int ret = 1;
459
460         if (s->full)
461                 return 0;
462
463         if (mm) {
464                 const struct vm_area_struct *vma;
465
466                 down_read(&mm->mmap_sem);
467                 vma = find_vma(mm, ip);
468                 if (vma) {
469                         file = vma->vm_file;
470                         vmstart = vma->vm_start;
471                 }
472                 if (file) {
473                         ret = trace_seq_path(s, &file->f_path);
474                         if (ret)
475                                 ret = trace_seq_printf(s, "[+0x%lx]",
476                                                        ip - vmstart);
477                 }
478                 up_read(&mm->mmap_sem);
479         }
480         if (ret && ((sym_flags & TRACE_ITER_SYM_ADDR) || !file))
481                 ret = trace_seq_printf(s, " <" IP_FMT ">", ip);
482         return ret;
483 }
484
485 int
486 seq_print_userip_objs(const struct userstack_entry *entry, struct trace_seq *s,
487                       unsigned long sym_flags)
488 {
489         struct mm_struct *mm = NULL;
490         int ret = 1;
491         unsigned int i;
492
493         if (trace_flags & TRACE_ITER_SYM_USEROBJ) {
494                 struct task_struct *task;
495                 /*
496                  * we do the lookup on the thread group leader,
497                  * since individual threads might have already quit!
498                  */
499                 rcu_read_lock();
500                 task = find_task_by_vpid(entry->tgid);
501                 if (task)
502                         mm = get_task_mm(task);
503                 rcu_read_unlock();
504         }
505
506         for (i = 0; i < FTRACE_STACK_ENTRIES; i++) {
507                 unsigned long ip = entry->caller[i];
508
509                 if (ip == ULONG_MAX || !ret)
510                         break;
511                 if (ret)
512                         ret = trace_seq_puts(s, " => ");
513                 if (!ip) {
514                         if (ret)
515                                 ret = trace_seq_puts(s, "??");
516                         if (ret)
517                                 ret = trace_seq_puts(s, "\n");
518                         continue;
519                 }
520                 if (!ret)
521                         break;
522                 if (ret)
523                         ret = seq_print_user_ip(s, mm, ip, sym_flags);
524                 ret = trace_seq_puts(s, "\n");
525         }
526
527         if (mm)
528                 mmput(mm);
529         return ret;
530 }
531
532 int
533 seq_print_ip_sym(struct trace_seq *s, unsigned long ip, unsigned long sym_flags)
534 {
535         int ret;
536
537         if (!ip)
538                 return trace_seq_printf(s, "0");
539
540         if (sym_flags & TRACE_ITER_SYM_OFFSET)
541                 ret = seq_print_sym_offset(s, "%s", ip);
542         else
543                 ret = seq_print_sym_short(s, "%s", ip);
544
545         if (!ret)
546                 return 0;
547
548         if (sym_flags & TRACE_ITER_SYM_ADDR)
549                 ret = trace_seq_printf(s, " <" IP_FMT ">", ip);
550         return ret;
551 }
552
553 /**
554  * trace_print_lat_fmt - print the irq, preempt and lockdep fields
555  * @s: trace seq struct to write to
556  * @entry: The trace entry field from the ring buffer
557  *
558  * Prints the generic fields of irqs off, in hard or softirq, preempt
559  * count.
560  */
561 int trace_print_lat_fmt(struct trace_seq *s, struct trace_entry *entry)
562 {
563         char hardsoft_irq;
564         char need_resched;
565         char irqs_off;
566         int hardirq;
567         int softirq;
568         int ret;
569
570         hardirq = entry->flags & TRACE_FLAG_HARDIRQ;
571         softirq = entry->flags & TRACE_FLAG_SOFTIRQ;
572
573         irqs_off =
574                 (entry->flags & TRACE_FLAG_IRQS_OFF) ? 'd' :
575                 (entry->flags & TRACE_FLAG_IRQS_NOSUPPORT) ? 'X' :
576                 '.';
577         need_resched =
578                 (entry->flags & TRACE_FLAG_NEED_RESCHED) ? 'N' : '.';
579         hardsoft_irq =
580                 (hardirq && softirq) ? 'H' :
581                 hardirq ? 'h' :
582                 softirq ? 's' :
583                 '.';
584
585         if (!trace_seq_printf(s, "%c%c%c",
586                               irqs_off, need_resched, hardsoft_irq))
587                 return 0;
588
589         if (entry->preempt_count)
590                 ret = trace_seq_printf(s, "%x", entry->preempt_count);
591         else
592                 ret = trace_seq_putc(s, '.');
593
594         return ret;
595 }
596
597 static int
598 lat_print_generic(struct trace_seq *s, struct trace_entry *entry, int cpu)
599 {
600         char comm[TASK_COMM_LEN];
601
602         trace_find_cmdline(entry->pid, comm);
603
604         if (!trace_seq_printf(s, "%8.8s-%-5d %3d",
605                               comm, entry->pid, cpu))
606                 return 0;
607
608         return trace_print_lat_fmt(s, entry);
609 }
610
611 static unsigned long preempt_mark_thresh = 100;
612
613 static int
614 lat_print_timestamp(struct trace_seq *s, u64 abs_usecs,
615                     unsigned long rel_usecs)
616 {
617         return trace_seq_printf(s, " %4lldus%c: ", abs_usecs,
618                                 rel_usecs > preempt_mark_thresh ? '!' :
619                                   rel_usecs > 1 ? '+' : ' ');
620 }
621
622 int trace_print_context(struct trace_iterator *iter)
623 {
624         struct trace_seq *s = &iter->seq;
625         struct trace_entry *entry = iter->ent;
626         unsigned long long t = ns2usecs(iter->ts);
627         unsigned long usec_rem = do_div(t, USEC_PER_SEC);
628         unsigned long secs = (unsigned long)t;
629         char comm[TASK_COMM_LEN];
630
631         trace_find_cmdline(entry->pid, comm);
632
633         return trace_seq_printf(s, "%16s-%-5d [%03d] %5lu.%06lu: ",
634                                 comm, entry->pid, iter->cpu, secs, usec_rem);
635 }
636
637 int trace_print_lat_context(struct trace_iterator *iter)
638 {
639         u64 next_ts;
640         int ret;
641         struct trace_seq *s = &iter->seq;
642         struct trace_entry *entry = iter->ent,
643                            *next_entry = trace_find_next_entry(iter, NULL,
644                                                                &next_ts);
645         unsigned long verbose = (trace_flags & TRACE_ITER_VERBOSE);
646         unsigned long abs_usecs = ns2usecs(iter->ts - iter->tr->time_start);
647         unsigned long rel_usecs;
648
649         if (!next_entry)
650                 next_ts = iter->ts;
651         rel_usecs = ns2usecs(next_ts - iter->ts);
652
653         if (verbose) {
654                 char comm[TASK_COMM_LEN];
655
656                 trace_find_cmdline(entry->pid, comm);
657
658                 ret = trace_seq_printf(s, "%16s %5d %3d %d %08x %08lx [%08llx]"
659                                        " %ld.%03ldms (+%ld.%03ldms): ", comm,
660                                        entry->pid, iter->cpu, entry->flags,
661                                        entry->preempt_count, iter->idx,
662                                        ns2usecs(iter->ts),
663                                        abs_usecs / USEC_PER_MSEC,
664                                        abs_usecs % USEC_PER_MSEC,
665                                        rel_usecs / USEC_PER_MSEC,
666                                        rel_usecs % USEC_PER_MSEC);
667         } else {
668                 ret = lat_print_generic(s, entry, iter->cpu);
669                 if (ret)
670                         ret = lat_print_timestamp(s, abs_usecs, rel_usecs);
671         }
672
673         return ret;
674 }
675
676 static const char state_to_char[] = TASK_STATE_TO_CHAR_STR;
677
678 static int task_state_char(unsigned long state)
679 {
680         int bit = state ? __ffs(state) + 1 : 0;
681
682         return bit < sizeof(state_to_char) - 1 ? state_to_char[bit] : '?';
683 }
684
685 /**
686  * ftrace_find_event - find a registered event
687  * @type: the type of event to look for
688  *
689  * Returns an event of type @type otherwise NULL
690  * Called with trace_event_read_lock() held.
691  */
692 struct trace_event *ftrace_find_event(int type)
693 {
694         struct trace_event *event;
695         struct hlist_node *n;
696         unsigned key;
697
698         key = type & (EVENT_HASHSIZE - 1);
699
700         hlist_for_each_entry(event, n, &event_hash[key], node) {
701                 if (event->type == type)
702                         return event;
703         }
704
705         return NULL;
706 }
707
708 static LIST_HEAD(ftrace_event_list);
709
710 static int trace_search_list(struct list_head **list)
711 {
712         struct trace_event *e;
713         int last = __TRACE_LAST_TYPE;
714
715         if (list_empty(&ftrace_event_list)) {
716                 *list = &ftrace_event_list;
717                 return last + 1;
718         }
719
720         /*
721          * We used up all possible max events,
722          * lets see if somebody freed one.
723          */
724         list_for_each_entry(e, &ftrace_event_list, list) {
725                 if (e->type != last + 1)
726                         break;
727                 last++;
728         }
729
730         /* Did we used up all 65 thousand events??? */
731         if ((last + 1) > FTRACE_MAX_EVENT)
732                 return 0;
733
734         *list = &e->list;
735         return last + 1;
736 }
737
738 void trace_event_read_lock(void)
739 {
740         down_read(&trace_event_mutex);
741 }
742
743 void trace_event_read_unlock(void)
744 {
745         up_read(&trace_event_mutex);
746 }
747
748 /**
749  * register_ftrace_event - register output for an event type
750  * @event: the event type to register
751  *
752  * Event types are stored in a hash and this hash is used to
753  * find a way to print an event. If the @event->type is set
754  * then it will use that type, otherwise it will assign a
755  * type to use.
756  *
757  * If you assign your own type, please make sure it is added
758  * to the trace_type enum in trace.h, to avoid collisions
759  * with the dynamic types.
760  *
761  * Returns the event type number or zero on error.
762  */
763 int register_ftrace_event(struct trace_event *event)
764 {
765         unsigned key;
766         int ret = 0;
767
768         down_write(&trace_event_mutex);
769
770         if (WARN_ON(!event))
771                 goto out;
772
773         if (WARN_ON(!event->funcs))
774                 goto out;
775
776         INIT_LIST_HEAD(&event->list);
777
778         if (!event->type) {
779                 struct list_head *list = NULL;
780
781                 if (next_event_type > FTRACE_MAX_EVENT) {
782
783                         event->type = trace_search_list(&list);
784                         if (!event->type)
785                                 goto out;
786
787                 } else {
788                         
789                         event->type = next_event_type++;
790                         list = &ftrace_event_list;
791                 }
792
793                 if (WARN_ON(ftrace_find_event(event->type)))
794                         goto out;
795
796                 list_add_tail(&event->list, list);
797
798         } else if (event->type > __TRACE_LAST_TYPE) {
799                 printk(KERN_WARNING "Need to add type to trace.h\n");
800                 WARN_ON(1);
801                 goto out;
802         } else {
803                 /* Is this event already used */
804                 if (ftrace_find_event(event->type))
805                         goto out;
806         }
807
808         if (event->funcs->trace == NULL)
809                 event->funcs->trace = trace_nop_print;
810         if (event->funcs->raw == NULL)
811                 event->funcs->raw = trace_nop_print;
812         if (event->funcs->hex == NULL)
813                 event->funcs->hex = trace_nop_print;
814         if (event->funcs->binary == NULL)
815                 event->funcs->binary = trace_nop_print;
816
817         key = event->type & (EVENT_HASHSIZE - 1);
818
819         hlist_add_head(&event->node, &event_hash[key]);
820
821         ret = event->type;
822  out:
823         up_write(&trace_event_mutex);
824
825         return ret;
826 }
827 EXPORT_SYMBOL_GPL(register_ftrace_event);
828
829 /*
830  * Used by module code with the trace_event_mutex held for write.
831  */
832 int __unregister_ftrace_event(struct trace_event *event)
833 {
834         hlist_del(&event->node);
835         list_del(&event->list);
836         return 0;
837 }
838
839 /**
840  * unregister_ftrace_event - remove a no longer used event
841  * @event: the event to remove
842  */
843 int unregister_ftrace_event(struct trace_event *event)
844 {
845         down_write(&trace_event_mutex);
846         __unregister_ftrace_event(event);
847         up_write(&trace_event_mutex);
848
849         return 0;
850 }
851 EXPORT_SYMBOL_GPL(unregister_ftrace_event);
852
853 /*
854  * Standard events
855  */
856
857 enum print_line_t trace_nop_print(struct trace_iterator *iter, int flags,
858                                   struct trace_event *event)
859 {
860         if (!trace_seq_printf(&iter->seq, "type: %d\n", iter->ent->type))
861                 return TRACE_TYPE_PARTIAL_LINE;
862
863         return TRACE_TYPE_HANDLED;
864 }
865
866 /* TRACE_FN */
867 static enum print_line_t trace_fn_trace(struct trace_iterator *iter, int flags,
868                                         struct trace_event *event)
869 {
870         struct ftrace_entry *field;
871         struct trace_seq *s = &iter->seq;
872
873         trace_assign_type(field, iter->ent);
874
875         if (!seq_print_ip_sym(s, field->ip, flags))
876                 goto partial;
877
878         if ((flags & TRACE_ITER_PRINT_PARENT) && field->parent_ip) {
879                 if (!trace_seq_printf(s, " <-"))
880                         goto partial;
881                 if (!seq_print_ip_sym(s,
882                                       field->parent_ip,
883                                       flags))
884                         goto partial;
885         }
886         if (!trace_seq_printf(s, "\n"))
887                 goto partial;
888
889         return TRACE_TYPE_HANDLED;
890
891  partial:
892         return TRACE_TYPE_PARTIAL_LINE;
893 }
894
895 static enum print_line_t trace_fn_raw(struct trace_iterator *iter, int flags,
896                                       struct trace_event *event)
897 {
898         struct ftrace_entry *field;
899
900         trace_assign_type(field, iter->ent);
901
902         if (!trace_seq_printf(&iter->seq, "%lx %lx\n",
903                               field->ip,
904                               field->parent_ip))
905                 return TRACE_TYPE_PARTIAL_LINE;
906
907         return TRACE_TYPE_HANDLED;
908 }
909
910 static enum print_line_t trace_fn_hex(struct trace_iterator *iter, int flags,
911                                       struct trace_event *event)
912 {
913         struct ftrace_entry *field;
914         struct trace_seq *s = &iter->seq;
915
916         trace_assign_type(field, iter->ent);
917
918         SEQ_PUT_HEX_FIELD_RET(s, field->ip);
919         SEQ_PUT_HEX_FIELD_RET(s, field->parent_ip);
920
921         return TRACE_TYPE_HANDLED;
922 }
923
924 static enum print_line_t trace_fn_bin(struct trace_iterator *iter, int flags,
925                                       struct trace_event *event)
926 {
927         struct ftrace_entry *field;
928         struct trace_seq *s = &iter->seq;
929
930         trace_assign_type(field, iter->ent);
931
932         SEQ_PUT_FIELD_RET(s, field->ip);
933         SEQ_PUT_FIELD_RET(s, field->parent_ip);
934
935         return TRACE_TYPE_HANDLED;
936 }
937
938 static struct trace_event_functions trace_fn_funcs = {
939         .trace          = trace_fn_trace,
940         .raw            = trace_fn_raw,
941         .hex            = trace_fn_hex,
942         .binary         = trace_fn_bin,
943 };
944
945 static struct trace_event trace_fn_event = {
946         .type           = TRACE_FN,
947         .funcs          = &trace_fn_funcs,
948 };
949
950 /* TRACE_CTX an TRACE_WAKE */
951 static enum print_line_t trace_ctxwake_print(struct trace_iterator *iter,
952                                              char *delim)
953 {
954         struct ctx_switch_entry *field;
955         char comm[TASK_COMM_LEN];
956         int S, T;
957
958
959         trace_assign_type(field, iter->ent);
960
961         T = task_state_char(field->next_state);
962         S = task_state_char(field->prev_state);
963         trace_find_cmdline(field->next_pid, comm);
964         if (!trace_seq_printf(&iter->seq,
965                               " %5d:%3d:%c %s [%03d] %5d:%3d:%c %s\n",
966                               field->prev_pid,
967                               field->prev_prio,
968                               S, delim,
969                               field->next_cpu,
970                               field->next_pid,
971                               field->next_prio,
972                               T, comm))
973                 return TRACE_TYPE_PARTIAL_LINE;
974
975         return TRACE_TYPE_HANDLED;
976 }
977
978 static enum print_line_t trace_ctx_print(struct trace_iterator *iter, int flags,
979                                          struct trace_event *event)
980 {
981         return trace_ctxwake_print(iter, "==>");
982 }
983
984 static enum print_line_t trace_wake_print(struct trace_iterator *iter,
985                                           int flags, struct trace_event *event)
986 {
987         return trace_ctxwake_print(iter, "  +");
988 }
989
990 static int trace_ctxwake_raw(struct trace_iterator *iter, char S)
991 {
992         struct ctx_switch_entry *field;
993         int T;
994
995         trace_assign_type(field, iter->ent);
996
997         if (!S)
998                 S = task_state_char(field->prev_state);
999         T = task_state_char(field->next_state);
1000         if (!trace_seq_printf(&iter->seq, "%d %d %c %d %d %d %c\n",
1001                               field->prev_pid,
1002                               field->prev_prio,
1003                               S,
1004                               field->next_cpu,
1005                               field->next_pid,
1006                               field->next_prio,
1007                               T))
1008                 return TRACE_TYPE_PARTIAL_LINE;
1009
1010         return TRACE_TYPE_HANDLED;
1011 }
1012
1013 static enum print_line_t trace_ctx_raw(struct trace_iterator *iter, int flags,
1014                                        struct trace_event *event)
1015 {
1016         return trace_ctxwake_raw(iter, 0);
1017 }
1018
1019 static enum print_line_t trace_wake_raw(struct trace_iterator *iter, int flags,
1020                                         struct trace_event *event)
1021 {
1022         return trace_ctxwake_raw(iter, '+');
1023 }
1024
1025
1026 static int trace_ctxwake_hex(struct trace_iterator *iter, char S)
1027 {
1028         struct ctx_switch_entry *field;
1029         struct trace_seq *s = &iter->seq;
1030         int T;
1031
1032         trace_assign_type(field, iter->ent);
1033
1034         if (!S)
1035                 S = task_state_char(field->prev_state);
1036         T = task_state_char(field->next_state);
1037
1038         SEQ_PUT_HEX_FIELD_RET(s, field->prev_pid);
1039         SEQ_PUT_HEX_FIELD_RET(s, field->prev_prio);
1040         SEQ_PUT_HEX_FIELD_RET(s, S);
1041         SEQ_PUT_HEX_FIELD_RET(s, field->next_cpu);
1042         SEQ_PUT_HEX_FIELD_RET(s, field->next_pid);
1043         SEQ_PUT_HEX_FIELD_RET(s, field->next_prio);
1044         SEQ_PUT_HEX_FIELD_RET(s, T);
1045
1046         return TRACE_TYPE_HANDLED;
1047 }
1048
1049 static enum print_line_t trace_ctx_hex(struct trace_iterator *iter, int flags,
1050                                        struct trace_event *event)
1051 {
1052         return trace_ctxwake_hex(iter, 0);
1053 }
1054
1055 static enum print_line_t trace_wake_hex(struct trace_iterator *iter, int flags,
1056                                         struct trace_event *event)
1057 {
1058         return trace_ctxwake_hex(iter, '+');
1059 }
1060
1061 static enum print_line_t trace_ctxwake_bin(struct trace_iterator *iter,
1062                                            int flags, struct trace_event *event)
1063 {
1064         struct ctx_switch_entry *field;
1065         struct trace_seq *s = &iter->seq;
1066
1067         trace_assign_type(field, iter->ent);
1068
1069         SEQ_PUT_FIELD_RET(s, field->prev_pid);
1070         SEQ_PUT_FIELD_RET(s, field->prev_prio);
1071         SEQ_PUT_FIELD_RET(s, field->prev_state);
1072         SEQ_PUT_FIELD_RET(s, field->next_pid);
1073         SEQ_PUT_FIELD_RET(s, field->next_prio);
1074         SEQ_PUT_FIELD_RET(s, field->next_state);
1075
1076         return TRACE_TYPE_HANDLED;
1077 }
1078
1079 static struct trace_event_functions trace_ctx_funcs = {
1080         .trace          = trace_ctx_print,
1081         .raw            = trace_ctx_raw,
1082         .hex            = trace_ctx_hex,
1083         .binary         = trace_ctxwake_bin,
1084 };
1085
1086 static struct trace_event trace_ctx_event = {
1087         .type           = TRACE_CTX,
1088         .funcs          = &trace_ctx_funcs,
1089 };
1090
1091 static struct trace_event_functions trace_wake_funcs = {
1092         .trace          = trace_wake_print,
1093         .raw            = trace_wake_raw,
1094         .hex            = trace_wake_hex,
1095         .binary         = trace_ctxwake_bin,
1096 };
1097
1098 static struct trace_event trace_wake_event = {
1099         .type           = TRACE_WAKE,
1100         .funcs          = &trace_wake_funcs,
1101 };
1102
1103 /* TRACE_STACK */
1104
1105 static enum print_line_t trace_stack_print(struct trace_iterator *iter,
1106                                            int flags, struct trace_event *event)
1107 {
1108         struct stack_entry *field;
1109         struct trace_seq *s = &iter->seq;
1110         unsigned long *p;
1111         unsigned long *end;
1112
1113         trace_assign_type(field, iter->ent);
1114         end = (unsigned long *)((long)iter->ent + iter->ent_size);
1115
1116         if (!trace_seq_puts(s, "<stack trace>\n"))
1117                 goto partial;
1118
1119         for (p = field->caller; p && *p != ULONG_MAX && p < end; p++) {
1120                 if (!trace_seq_puts(s, " => "))
1121                         goto partial;
1122
1123                 if (!seq_print_ip_sym(s, *p, flags))
1124                         goto partial;
1125                 if (!trace_seq_puts(s, "\n"))
1126                         goto partial;
1127         }
1128
1129         return TRACE_TYPE_HANDLED;
1130
1131  partial:
1132         return TRACE_TYPE_PARTIAL_LINE;
1133 }
1134
1135 static struct trace_event_functions trace_stack_funcs = {
1136         .trace          = trace_stack_print,
1137 };
1138
1139 static struct trace_event trace_stack_event = {
1140         .type           = TRACE_STACK,
1141         .funcs          = &trace_stack_funcs,
1142 };
1143
1144 /* TRACE_USER_STACK */
1145 static enum print_line_t trace_user_stack_print(struct trace_iterator *iter,
1146                                                 int flags, struct trace_event *event)
1147 {
1148         struct userstack_entry *field;
1149         struct trace_seq *s = &iter->seq;
1150
1151         trace_assign_type(field, iter->ent);
1152
1153         if (!trace_seq_puts(s, "<user stack trace>\n"))
1154                 goto partial;
1155
1156         if (!seq_print_userip_objs(field, s, flags))
1157                 goto partial;
1158
1159         return TRACE_TYPE_HANDLED;
1160
1161  partial:
1162         return TRACE_TYPE_PARTIAL_LINE;
1163 }
1164
1165 static struct trace_event_functions trace_user_stack_funcs = {
1166         .trace          = trace_user_stack_print,
1167 };
1168
1169 static struct trace_event trace_user_stack_event = {
1170         .type           = TRACE_USER_STACK,
1171         .funcs          = &trace_user_stack_funcs,
1172 };
1173
1174 /* TRACE_BPRINT */
1175 static enum print_line_t
1176 trace_bprint_print(struct trace_iterator *iter, int flags,
1177                    struct trace_event *event)
1178 {
1179         struct trace_entry *entry = iter->ent;
1180         struct trace_seq *s = &iter->seq;
1181         struct bprint_entry *field;
1182
1183         trace_assign_type(field, entry);
1184
1185         if (!seq_print_ip_sym(s, field->ip, flags))
1186                 goto partial;
1187
1188         if (!trace_seq_puts(s, ": "))
1189                 goto partial;
1190
1191         if (!trace_seq_bprintf(s, field->fmt, field->buf))
1192                 goto partial;
1193
1194         return TRACE_TYPE_HANDLED;
1195
1196  partial:
1197         return TRACE_TYPE_PARTIAL_LINE;
1198 }
1199
1200
1201 static enum print_line_t
1202 trace_bprint_raw(struct trace_iterator *iter, int flags,
1203                  struct trace_event *event)
1204 {
1205         struct bprint_entry *field;
1206         struct trace_seq *s = &iter->seq;
1207
1208         trace_assign_type(field, iter->ent);
1209
1210         if (!trace_seq_printf(s, ": %lx : ", field->ip))
1211                 goto partial;
1212
1213         if (!trace_seq_bprintf(s, field->fmt, field->buf))
1214                 goto partial;
1215
1216         return TRACE_TYPE_HANDLED;
1217
1218  partial:
1219         return TRACE_TYPE_PARTIAL_LINE;
1220 }
1221
1222 static struct trace_event_functions trace_bprint_funcs = {
1223         .trace          = trace_bprint_print,
1224         .raw            = trace_bprint_raw,
1225 };
1226
1227 static struct trace_event trace_bprint_event = {
1228         .type           = TRACE_BPRINT,
1229         .funcs          = &trace_bprint_funcs,
1230 };
1231
1232 /* TRACE_PRINT */
1233 static enum print_line_t trace_print_print(struct trace_iterator *iter,
1234                                            int flags, struct trace_event *event)
1235 {
1236         struct print_entry *field;
1237         struct trace_seq *s = &iter->seq;
1238
1239         trace_assign_type(field, iter->ent);
1240
1241         if (!seq_print_ip_sym(s, field->ip, flags))
1242                 goto partial;
1243
1244         if (!trace_seq_printf(s, ": %s", field->buf))
1245                 goto partial;
1246
1247         return TRACE_TYPE_HANDLED;
1248
1249  partial:
1250         return TRACE_TYPE_PARTIAL_LINE;
1251 }
1252
1253 static enum print_line_t trace_print_raw(struct trace_iterator *iter, int flags,
1254                                          struct trace_event *event)
1255 {
1256         struct print_entry *field;
1257
1258         trace_assign_type(field, iter->ent);
1259
1260         if (!trace_seq_printf(&iter->seq, "# %lx %s", field->ip, field->buf))
1261                 goto partial;
1262
1263         return TRACE_TYPE_HANDLED;
1264
1265  partial:
1266         return TRACE_TYPE_PARTIAL_LINE;
1267 }
1268
1269 static struct trace_event_functions trace_print_funcs = {
1270         .trace          = trace_print_print,
1271         .raw            = trace_print_raw,
1272 };
1273
1274 static struct trace_event trace_print_event = {
1275         .type           = TRACE_PRINT,
1276         .funcs          = &trace_print_funcs,
1277 };
1278
1279
1280 static struct trace_event *events[] __initdata = {
1281         &trace_fn_event,
1282         &trace_ctx_event,
1283         &trace_wake_event,
1284         &trace_stack_event,
1285         &trace_user_stack_event,
1286         &trace_bprint_event,
1287         &trace_print_event,
1288         NULL
1289 };
1290
1291 __init static int init_events(void)
1292 {
1293         struct trace_event *event;
1294         int i, ret;
1295
1296         for (i = 0; events[i]; i++) {
1297                 event = events[i];
1298
1299                 ret = register_ftrace_event(event);
1300                 if (!ret) {
1301                         printk(KERN_WARNING "event %d failed to register\n",
1302                                event->type);
1303                         WARN_ON_ONCE(1);
1304                 }
1305         }
1306
1307         return 0;
1308 }
1309 device_initcall(init_events);