hugetlbfs: fix mmap failure in unaligned size request
[linux-2.6.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, const struct path *path)
268 {
269         unsigned char *p;
270
271         if (s->full)
272                 return 0;
273
274         if (s->len >= (PAGE_SIZE - 1)) {
275                 s->full = 1;
276                 return 0;
277         }
278
279         p = d_path(path, s->buffer + s->len, PAGE_SIZE - s->len);
280         if (!IS_ERR(p)) {
281                 p = mangle_path(s->buffer + s->len, p, "\n");
282                 if (p) {
283                         s->len = p - s->buffer;
284                         return 1;
285                 }
286         } else {
287                 s->buffer[s->len++] = '?';
288                 return 1;
289         }
290
291         s->full = 1;
292         return 0;
293 }
294
295 const char *
296 ftrace_print_flags_seq(struct trace_seq *p, const char *delim,
297                        unsigned long flags,
298                        const struct trace_print_flags *flag_array)
299 {
300         unsigned long mask;
301         const char *str;
302         const char *ret = p->buffer + p->len;
303         int i, first = 1;
304
305         for (i = 0;  flag_array[i].name && flags; i++) {
306
307                 mask = flag_array[i].mask;
308                 if ((flags & mask) != mask)
309                         continue;
310
311                 str = flag_array[i].name;
312                 flags &= ~mask;
313                 if (!first && delim)
314                         trace_seq_puts(p, delim);
315                 else
316                         first = 0;
317                 trace_seq_puts(p, str);
318         }
319
320         /* check for left over flags */
321         if (flags) {
322                 if (!first && delim)
323                         trace_seq_puts(p, delim);
324                 trace_seq_printf(p, "0x%lx", flags);
325         }
326
327         trace_seq_putc(p, 0);
328
329         return ret;
330 }
331 EXPORT_SYMBOL(ftrace_print_flags_seq);
332
333 const char *
334 ftrace_print_symbols_seq(struct trace_seq *p, unsigned long val,
335                          const struct trace_print_flags *symbol_array)
336 {
337         int i;
338         const char *ret = p->buffer + p->len;
339
340         for (i = 0;  symbol_array[i].name; i++) {
341
342                 if (val != symbol_array[i].mask)
343                         continue;
344
345                 trace_seq_puts(p, symbol_array[i].name);
346                 break;
347         }
348
349         if (ret == (const char *)(p->buffer + p->len))
350                 trace_seq_printf(p, "0x%lx", val);
351                 
352         trace_seq_putc(p, 0);
353
354         return ret;
355 }
356 EXPORT_SYMBOL(ftrace_print_symbols_seq);
357
358 #if BITS_PER_LONG == 32
359 const char *
360 ftrace_print_symbols_seq_u64(struct trace_seq *p, unsigned long long val,
361                          const struct trace_print_flags_u64 *symbol_array)
362 {
363         int i;
364         const char *ret = p->buffer + p->len;
365
366         for (i = 0;  symbol_array[i].name; i++) {
367
368                 if (val != symbol_array[i].mask)
369                         continue;
370
371                 trace_seq_puts(p, symbol_array[i].name);
372                 break;
373         }
374
375         if (ret == (const char *)(p->buffer + p->len))
376                 trace_seq_printf(p, "0x%llx", val);
377
378         trace_seq_putc(p, 0);
379
380         return ret;
381 }
382 EXPORT_SYMBOL(ftrace_print_symbols_seq_u64);
383 #endif
384
385 const char *
386 ftrace_print_hex_seq(struct trace_seq *p, const unsigned char *buf, int buf_len)
387 {
388         int i;
389         const char *ret = p->buffer + p->len;
390
391         for (i = 0; i < buf_len; i++)
392                 trace_seq_printf(p, "%s%2.2x", i == 0 ? "" : " ", buf[i]);
393
394         trace_seq_putc(p, 0);
395
396         return ret;
397 }
398 EXPORT_SYMBOL(ftrace_print_hex_seq);
399
400 #ifdef CONFIG_KRETPROBES
401 static inline const char *kretprobed(const char *name)
402 {
403         static const char tramp_name[] = "kretprobe_trampoline";
404         int size = sizeof(tramp_name);
405
406         if (strncmp(tramp_name, name, size) == 0)
407                 return "[unknown/kretprobe'd]";
408         return name;
409 }
410 #else
411 static inline const char *kretprobed(const char *name)
412 {
413         return name;
414 }
415 #endif /* CONFIG_KRETPROBES */
416
417 static int
418 seq_print_sym_short(struct trace_seq *s, const char *fmt, unsigned long address)
419 {
420 #ifdef CONFIG_KALLSYMS
421         char str[KSYM_SYMBOL_LEN];
422         const char *name;
423
424         kallsyms_lookup(address, NULL, NULL, NULL, str);
425
426         name = kretprobed(str);
427
428         return trace_seq_printf(s, fmt, name);
429 #endif
430         return 1;
431 }
432
433 static int
434 seq_print_sym_offset(struct trace_seq *s, const char *fmt,
435                      unsigned long address)
436 {
437 #ifdef CONFIG_KALLSYMS
438         char str[KSYM_SYMBOL_LEN];
439         const char *name;
440
441         sprint_symbol(str, address);
442         name = kretprobed(str);
443
444         return trace_seq_printf(s, fmt, name);
445 #endif
446         return 1;
447 }
448
449 #ifndef CONFIG_64BIT
450 # define IP_FMT "%08lx"
451 #else
452 # define IP_FMT "%016lx"
453 #endif
454
455 int seq_print_user_ip(struct trace_seq *s, struct mm_struct *mm,
456                       unsigned long ip, unsigned long sym_flags)
457 {
458         struct file *file = NULL;
459         unsigned long vmstart = 0;
460         int ret = 1;
461
462         if (s->full)
463                 return 0;
464
465         if (mm) {
466                 const struct vm_area_struct *vma;
467
468                 down_read(&mm->mmap_sem);
469                 vma = find_vma(mm, ip);
470                 if (vma) {
471                         file = vma->vm_file;
472                         vmstart = vma->vm_start;
473                 }
474                 if (file) {
475                         ret = trace_seq_path(s, &file->f_path);
476                         if (ret)
477                                 ret = trace_seq_printf(s, "[+0x%lx]",
478                                                        ip - vmstart);
479                 }
480                 up_read(&mm->mmap_sem);
481         }
482         if (ret && ((sym_flags & TRACE_ITER_SYM_ADDR) || !file))
483                 ret = trace_seq_printf(s, " <" IP_FMT ">", ip);
484         return ret;
485 }
486
487 int
488 seq_print_userip_objs(const struct userstack_entry *entry, struct trace_seq *s,
489                       unsigned long sym_flags)
490 {
491         struct mm_struct *mm = NULL;
492         int ret = 1;
493         unsigned int i;
494
495         if (trace_flags & TRACE_ITER_SYM_USEROBJ) {
496                 struct task_struct *task;
497                 /*
498                  * we do the lookup on the thread group leader,
499                  * since individual threads might have already quit!
500                  */
501                 rcu_read_lock();
502                 task = find_task_by_vpid(entry->tgid);
503                 if (task)
504                         mm = get_task_mm(task);
505                 rcu_read_unlock();
506         }
507
508         for (i = 0; i < FTRACE_STACK_ENTRIES; i++) {
509                 unsigned long ip = entry->caller[i];
510
511                 if (ip == ULONG_MAX || !ret)
512                         break;
513                 if (ret)
514                         ret = trace_seq_puts(s, " => ");
515                 if (!ip) {
516                         if (ret)
517                                 ret = trace_seq_puts(s, "??");
518                         if (ret)
519                                 ret = trace_seq_puts(s, "\n");
520                         continue;
521                 }
522                 if (!ret)
523                         break;
524                 if (ret)
525                         ret = seq_print_user_ip(s, mm, ip, sym_flags);
526                 ret = trace_seq_puts(s, "\n");
527         }
528
529         if (mm)
530                 mmput(mm);
531         return ret;
532 }
533
534 int
535 seq_print_ip_sym(struct trace_seq *s, unsigned long ip, unsigned long sym_flags)
536 {
537         int ret;
538
539         if (!ip)
540                 return trace_seq_printf(s, "0");
541
542         if (sym_flags & TRACE_ITER_SYM_OFFSET)
543                 ret = seq_print_sym_offset(s, "%s", ip);
544         else
545                 ret = seq_print_sym_short(s, "%s", ip);
546
547         if (!ret)
548                 return 0;
549
550         if (sym_flags & TRACE_ITER_SYM_ADDR)
551                 ret = trace_seq_printf(s, " <" IP_FMT ">", ip);
552         return ret;
553 }
554
555 /**
556  * trace_print_lat_fmt - print the irq, preempt and lockdep fields
557  * @s: trace seq struct to write to
558  * @entry: The trace entry field from the ring buffer
559  *
560  * Prints the generic fields of irqs off, in hard or softirq, preempt
561  * count.
562  */
563 int trace_print_lat_fmt(struct trace_seq *s, struct trace_entry *entry)
564 {
565         char hardsoft_irq;
566         char need_resched;
567         char irqs_off;
568         int hardirq;
569         int softirq;
570         int ret;
571
572         hardirq = entry->flags & TRACE_FLAG_HARDIRQ;
573         softirq = entry->flags & TRACE_FLAG_SOFTIRQ;
574
575         irqs_off =
576                 (entry->flags & TRACE_FLAG_IRQS_OFF) ? 'd' :
577                 (entry->flags & TRACE_FLAG_IRQS_NOSUPPORT) ? 'X' :
578                 '.';
579         need_resched =
580                 (entry->flags & TRACE_FLAG_NEED_RESCHED) ? 'N' : '.';
581         hardsoft_irq =
582                 (hardirq && softirq) ? 'H' :
583                 hardirq ? 'h' :
584                 softirq ? 's' :
585                 '.';
586
587         if (!trace_seq_printf(s, "%c%c%c",
588                               irqs_off, need_resched, hardsoft_irq))
589                 return 0;
590
591         if (entry->preempt_count)
592                 ret = trace_seq_printf(s, "%x", entry->preempt_count);
593         else
594                 ret = trace_seq_putc(s, '.');
595
596         return ret;
597 }
598
599 static int
600 lat_print_generic(struct trace_seq *s, struct trace_entry *entry, int cpu)
601 {
602         char comm[TASK_COMM_LEN];
603
604         trace_find_cmdline(entry->pid, comm);
605
606         if (!trace_seq_printf(s, "%8.8s-%-5d %3d",
607                               comm, entry->pid, cpu))
608                 return 0;
609
610         return trace_print_lat_fmt(s, entry);
611 }
612
613 static unsigned long preempt_mark_thresh = 100;
614
615 static int
616 lat_print_timestamp(struct trace_seq *s, u64 abs_usecs,
617                     unsigned long rel_usecs)
618 {
619         return trace_seq_printf(s, " %4lldus%c: ", abs_usecs,
620                                 rel_usecs > preempt_mark_thresh ? '!' :
621                                   rel_usecs > 1 ? '+' : ' ');
622 }
623
624 int trace_print_context(struct trace_iterator *iter)
625 {
626         struct trace_seq *s = &iter->seq;
627         struct trace_entry *entry = iter->ent;
628         unsigned long long t = ns2usecs(iter->ts);
629         unsigned long usec_rem = do_div(t, USEC_PER_SEC);
630         unsigned long secs = (unsigned long)t;
631         char comm[TASK_COMM_LEN];
632         int ret;
633
634         trace_find_cmdline(entry->pid, comm);
635
636         ret = trace_seq_printf(s, "%16s-%-5d [%03d] ",
637                                comm, entry->pid, iter->cpu);
638         if (!ret)
639                 return 0;
640
641         if (trace_flags & TRACE_ITER_IRQ_INFO) {
642                 ret = trace_print_lat_fmt(s, entry);
643                 if (!ret)
644                         return 0;
645         }
646
647         return trace_seq_printf(s, " %5lu.%06lu: ",
648                                 secs, usec_rem);
649 }
650
651 int trace_print_lat_context(struct trace_iterator *iter)
652 {
653         u64 next_ts;
654         int ret;
655         /* trace_find_next_entry will reset ent_size */
656         int ent_size = iter->ent_size;
657         struct trace_seq *s = &iter->seq;
658         struct trace_entry *entry = iter->ent,
659                            *next_entry = trace_find_next_entry(iter, NULL,
660                                                                &next_ts);
661         unsigned long verbose = (trace_flags & TRACE_ITER_VERBOSE);
662         unsigned long abs_usecs = ns2usecs(iter->ts - iter->tr->time_start);
663         unsigned long rel_usecs;
664
665         /* Restore the original ent_size */
666         iter->ent_size = ent_size;
667
668         if (!next_entry)
669                 next_ts = iter->ts;
670         rel_usecs = ns2usecs(next_ts - iter->ts);
671
672         if (verbose) {
673                 char comm[TASK_COMM_LEN];
674
675                 trace_find_cmdline(entry->pid, comm);
676
677                 ret = trace_seq_printf(s, "%16s %5d %3d %d %08x %08lx [%08llx]"
678                                        " %ld.%03ldms (+%ld.%03ldms): ", comm,
679                                        entry->pid, iter->cpu, entry->flags,
680                                        entry->preempt_count, iter->idx,
681                                        ns2usecs(iter->ts),
682                                        abs_usecs / USEC_PER_MSEC,
683                                        abs_usecs % USEC_PER_MSEC,
684                                        rel_usecs / USEC_PER_MSEC,
685                                        rel_usecs % USEC_PER_MSEC);
686         } else {
687                 ret = lat_print_generic(s, entry, iter->cpu);
688                 if (ret)
689                         ret = lat_print_timestamp(s, abs_usecs, rel_usecs);
690         }
691
692         return ret;
693 }
694
695 static const char state_to_char[] = TASK_STATE_TO_CHAR_STR;
696
697 static int task_state_char(unsigned long state)
698 {
699         int bit = state ? __ffs(state) + 1 : 0;
700
701         return bit < sizeof(state_to_char) - 1 ? state_to_char[bit] : '?';
702 }
703
704 /**
705  * ftrace_find_event - find a registered event
706  * @type: the type of event to look for
707  *
708  * Returns an event of type @type otherwise NULL
709  * Called with trace_event_read_lock() held.
710  */
711 struct trace_event *ftrace_find_event(int type)
712 {
713         struct trace_event *event;
714         struct hlist_node *n;
715         unsigned key;
716
717         key = type & (EVENT_HASHSIZE - 1);
718
719         hlist_for_each_entry(event, n, &event_hash[key], node) {
720                 if (event->type == type)
721                         return event;
722         }
723
724         return NULL;
725 }
726
727 static LIST_HEAD(ftrace_event_list);
728
729 static int trace_search_list(struct list_head **list)
730 {
731         struct trace_event *e;
732         int last = __TRACE_LAST_TYPE;
733
734         if (list_empty(&ftrace_event_list)) {
735                 *list = &ftrace_event_list;
736                 return last + 1;
737         }
738
739         /*
740          * We used up all possible max events,
741          * lets see if somebody freed one.
742          */
743         list_for_each_entry(e, &ftrace_event_list, list) {
744                 if (e->type != last + 1)
745                         break;
746                 last++;
747         }
748
749         /* Did we used up all 65 thousand events??? */
750         if ((last + 1) > FTRACE_MAX_EVENT)
751                 return 0;
752
753         *list = &e->list;
754         return last + 1;
755 }
756
757 void trace_event_read_lock(void)
758 {
759         down_read(&trace_event_mutex);
760 }
761
762 void trace_event_read_unlock(void)
763 {
764         up_read(&trace_event_mutex);
765 }
766
767 /**
768  * register_ftrace_event - register output for an event type
769  * @event: the event type to register
770  *
771  * Event types are stored in a hash and this hash is used to
772  * find a way to print an event. If the @event->type is set
773  * then it will use that type, otherwise it will assign a
774  * type to use.
775  *
776  * If you assign your own type, please make sure it is added
777  * to the trace_type enum in trace.h, to avoid collisions
778  * with the dynamic types.
779  *
780  * Returns the event type number or zero on error.
781  */
782 int register_ftrace_event(struct trace_event *event)
783 {
784         unsigned key;
785         int ret = 0;
786
787         down_write(&trace_event_mutex);
788
789         if (WARN_ON(!event))
790                 goto out;
791
792         if (WARN_ON(!event->funcs))
793                 goto out;
794
795         INIT_LIST_HEAD(&event->list);
796
797         if (!event->type) {
798                 struct list_head *list = NULL;
799
800                 if (next_event_type > FTRACE_MAX_EVENT) {
801
802                         event->type = trace_search_list(&list);
803                         if (!event->type)
804                                 goto out;
805
806                 } else {
807                         
808                         event->type = next_event_type++;
809                         list = &ftrace_event_list;
810                 }
811
812                 if (WARN_ON(ftrace_find_event(event->type)))
813                         goto out;
814
815                 list_add_tail(&event->list, list);
816
817         } else if (event->type > __TRACE_LAST_TYPE) {
818                 printk(KERN_WARNING "Need to add type to trace.h\n");
819                 WARN_ON(1);
820                 goto out;
821         } else {
822                 /* Is this event already used */
823                 if (ftrace_find_event(event->type))
824                         goto out;
825         }
826
827         if (event->funcs->trace == NULL)
828                 event->funcs->trace = trace_nop_print;
829         if (event->funcs->raw == NULL)
830                 event->funcs->raw = trace_nop_print;
831         if (event->funcs->hex == NULL)
832                 event->funcs->hex = trace_nop_print;
833         if (event->funcs->binary == NULL)
834                 event->funcs->binary = trace_nop_print;
835
836         key = event->type & (EVENT_HASHSIZE - 1);
837
838         hlist_add_head(&event->node, &event_hash[key]);
839
840         ret = event->type;
841  out:
842         up_write(&trace_event_mutex);
843
844         return ret;
845 }
846 EXPORT_SYMBOL_GPL(register_ftrace_event);
847
848 /*
849  * Used by module code with the trace_event_mutex held for write.
850  */
851 int __unregister_ftrace_event(struct trace_event *event)
852 {
853         hlist_del(&event->node);
854         list_del(&event->list);
855         return 0;
856 }
857
858 /**
859  * unregister_ftrace_event - remove a no longer used event
860  * @event: the event to remove
861  */
862 int unregister_ftrace_event(struct trace_event *event)
863 {
864         down_write(&trace_event_mutex);
865         __unregister_ftrace_event(event);
866         up_write(&trace_event_mutex);
867
868         return 0;
869 }
870 EXPORT_SYMBOL_GPL(unregister_ftrace_event);
871
872 /*
873  * Standard events
874  */
875
876 enum print_line_t trace_nop_print(struct trace_iterator *iter, int flags,
877                                   struct trace_event *event)
878 {
879         if (!trace_seq_printf(&iter->seq, "type: %d\n", iter->ent->type))
880                 return TRACE_TYPE_PARTIAL_LINE;
881
882         return TRACE_TYPE_HANDLED;
883 }
884
885 /* TRACE_FN */
886 static enum print_line_t trace_fn_trace(struct trace_iterator *iter, int flags,
887                                         struct trace_event *event)
888 {
889         struct ftrace_entry *field;
890         struct trace_seq *s = &iter->seq;
891
892         trace_assign_type(field, iter->ent);
893
894         if (!seq_print_ip_sym(s, field->ip, flags))
895                 goto partial;
896
897         if ((flags & TRACE_ITER_PRINT_PARENT) && field->parent_ip) {
898                 if (!trace_seq_printf(s, " <-"))
899                         goto partial;
900                 if (!seq_print_ip_sym(s,
901                                       field->parent_ip,
902                                       flags))
903                         goto partial;
904         }
905         if (!trace_seq_printf(s, "\n"))
906                 goto partial;
907
908         return TRACE_TYPE_HANDLED;
909
910  partial:
911         return TRACE_TYPE_PARTIAL_LINE;
912 }
913
914 static enum print_line_t trace_fn_raw(struct trace_iterator *iter, int flags,
915                                       struct trace_event *event)
916 {
917         struct ftrace_entry *field;
918
919         trace_assign_type(field, iter->ent);
920
921         if (!trace_seq_printf(&iter->seq, "%lx %lx\n",
922                               field->ip,
923                               field->parent_ip))
924                 return TRACE_TYPE_PARTIAL_LINE;
925
926         return TRACE_TYPE_HANDLED;
927 }
928
929 static enum print_line_t trace_fn_hex(struct trace_iterator *iter, int flags,
930                                       struct trace_event *event)
931 {
932         struct ftrace_entry *field;
933         struct trace_seq *s = &iter->seq;
934
935         trace_assign_type(field, iter->ent);
936
937         SEQ_PUT_HEX_FIELD_RET(s, field->ip);
938         SEQ_PUT_HEX_FIELD_RET(s, field->parent_ip);
939
940         return TRACE_TYPE_HANDLED;
941 }
942
943 static enum print_line_t trace_fn_bin(struct trace_iterator *iter, int flags,
944                                       struct trace_event *event)
945 {
946         struct ftrace_entry *field;
947         struct trace_seq *s = &iter->seq;
948
949         trace_assign_type(field, iter->ent);
950
951         SEQ_PUT_FIELD_RET(s, field->ip);
952         SEQ_PUT_FIELD_RET(s, field->parent_ip);
953
954         return TRACE_TYPE_HANDLED;
955 }
956
957 static struct trace_event_functions trace_fn_funcs = {
958         .trace          = trace_fn_trace,
959         .raw            = trace_fn_raw,
960         .hex            = trace_fn_hex,
961         .binary         = trace_fn_bin,
962 };
963
964 static struct trace_event trace_fn_event = {
965         .type           = TRACE_FN,
966         .funcs          = &trace_fn_funcs,
967 };
968
969 /* TRACE_CTX an TRACE_WAKE */
970 static enum print_line_t trace_ctxwake_print(struct trace_iterator *iter,
971                                              char *delim)
972 {
973         struct ctx_switch_entry *field;
974         char comm[TASK_COMM_LEN];
975         int S, T;
976
977
978         trace_assign_type(field, iter->ent);
979
980         T = task_state_char(field->next_state);
981         S = task_state_char(field->prev_state);
982         trace_find_cmdline(field->next_pid, comm);
983         if (!trace_seq_printf(&iter->seq,
984                               " %5d:%3d:%c %s [%03d] %5d:%3d:%c %s\n",
985                               field->prev_pid,
986                               field->prev_prio,
987                               S, delim,
988                               field->next_cpu,
989                               field->next_pid,
990                               field->next_prio,
991                               T, comm))
992                 return TRACE_TYPE_PARTIAL_LINE;
993
994         return TRACE_TYPE_HANDLED;
995 }
996
997 static enum print_line_t trace_ctx_print(struct trace_iterator *iter, int flags,
998                                          struct trace_event *event)
999 {
1000         return trace_ctxwake_print(iter, "==>");
1001 }
1002
1003 static enum print_line_t trace_wake_print(struct trace_iterator *iter,
1004                                           int flags, struct trace_event *event)
1005 {
1006         return trace_ctxwake_print(iter, "  +");
1007 }
1008
1009 static int trace_ctxwake_raw(struct trace_iterator *iter, char S)
1010 {
1011         struct ctx_switch_entry *field;
1012         int T;
1013
1014         trace_assign_type(field, iter->ent);
1015
1016         if (!S)
1017                 S = task_state_char(field->prev_state);
1018         T = task_state_char(field->next_state);
1019         if (!trace_seq_printf(&iter->seq, "%d %d %c %d %d %d %c\n",
1020                               field->prev_pid,
1021                               field->prev_prio,
1022                               S,
1023                               field->next_cpu,
1024                               field->next_pid,
1025                               field->next_prio,
1026                               T))
1027                 return TRACE_TYPE_PARTIAL_LINE;
1028
1029         return TRACE_TYPE_HANDLED;
1030 }
1031
1032 static enum print_line_t trace_ctx_raw(struct trace_iterator *iter, int flags,
1033                                        struct trace_event *event)
1034 {
1035         return trace_ctxwake_raw(iter, 0);
1036 }
1037
1038 static enum print_line_t trace_wake_raw(struct trace_iterator *iter, int flags,
1039                                         struct trace_event *event)
1040 {
1041         return trace_ctxwake_raw(iter, '+');
1042 }
1043
1044
1045 static int trace_ctxwake_hex(struct trace_iterator *iter, char S)
1046 {
1047         struct ctx_switch_entry *field;
1048         struct trace_seq *s = &iter->seq;
1049         int T;
1050
1051         trace_assign_type(field, iter->ent);
1052
1053         if (!S)
1054                 S = task_state_char(field->prev_state);
1055         T = task_state_char(field->next_state);
1056
1057         SEQ_PUT_HEX_FIELD_RET(s, field->prev_pid);
1058         SEQ_PUT_HEX_FIELD_RET(s, field->prev_prio);
1059         SEQ_PUT_HEX_FIELD_RET(s, S);
1060         SEQ_PUT_HEX_FIELD_RET(s, field->next_cpu);
1061         SEQ_PUT_HEX_FIELD_RET(s, field->next_pid);
1062         SEQ_PUT_HEX_FIELD_RET(s, field->next_prio);
1063         SEQ_PUT_HEX_FIELD_RET(s, T);
1064
1065         return TRACE_TYPE_HANDLED;
1066 }
1067
1068 static enum print_line_t trace_ctx_hex(struct trace_iterator *iter, int flags,
1069                                        struct trace_event *event)
1070 {
1071         return trace_ctxwake_hex(iter, 0);
1072 }
1073
1074 static enum print_line_t trace_wake_hex(struct trace_iterator *iter, int flags,
1075                                         struct trace_event *event)
1076 {
1077         return trace_ctxwake_hex(iter, '+');
1078 }
1079
1080 static enum print_line_t trace_ctxwake_bin(struct trace_iterator *iter,
1081                                            int flags, struct trace_event *event)
1082 {
1083         struct ctx_switch_entry *field;
1084         struct trace_seq *s = &iter->seq;
1085
1086         trace_assign_type(field, iter->ent);
1087
1088         SEQ_PUT_FIELD_RET(s, field->prev_pid);
1089         SEQ_PUT_FIELD_RET(s, field->prev_prio);
1090         SEQ_PUT_FIELD_RET(s, field->prev_state);
1091         SEQ_PUT_FIELD_RET(s, field->next_pid);
1092         SEQ_PUT_FIELD_RET(s, field->next_prio);
1093         SEQ_PUT_FIELD_RET(s, field->next_state);
1094
1095         return TRACE_TYPE_HANDLED;
1096 }
1097
1098 static struct trace_event_functions trace_ctx_funcs = {
1099         .trace          = trace_ctx_print,
1100         .raw            = trace_ctx_raw,
1101         .hex            = trace_ctx_hex,
1102         .binary         = trace_ctxwake_bin,
1103 };
1104
1105 static struct trace_event trace_ctx_event = {
1106         .type           = TRACE_CTX,
1107         .funcs          = &trace_ctx_funcs,
1108 };
1109
1110 static struct trace_event_functions trace_wake_funcs = {
1111         .trace          = trace_wake_print,
1112         .raw            = trace_wake_raw,
1113         .hex            = trace_wake_hex,
1114         .binary         = trace_ctxwake_bin,
1115 };
1116
1117 static struct trace_event trace_wake_event = {
1118         .type           = TRACE_WAKE,
1119         .funcs          = &trace_wake_funcs,
1120 };
1121
1122 /* TRACE_STACK */
1123
1124 static enum print_line_t trace_stack_print(struct trace_iterator *iter,
1125                                            int flags, struct trace_event *event)
1126 {
1127         struct stack_entry *field;
1128         struct trace_seq *s = &iter->seq;
1129         unsigned long *p;
1130         unsigned long *end;
1131
1132         trace_assign_type(field, iter->ent);
1133         end = (unsigned long *)((long)iter->ent + iter->ent_size);
1134
1135         if (!trace_seq_puts(s, "<stack trace>\n"))
1136                 goto partial;
1137
1138         for (p = field->caller; p && *p != ULONG_MAX && p < end; p++) {
1139                 if (!trace_seq_puts(s, " => "))
1140                         goto partial;
1141
1142                 if (!seq_print_ip_sym(s, *p, flags))
1143                         goto partial;
1144                 if (!trace_seq_puts(s, "\n"))
1145                         goto partial;
1146         }
1147
1148         return TRACE_TYPE_HANDLED;
1149
1150  partial:
1151         return TRACE_TYPE_PARTIAL_LINE;
1152 }
1153
1154 static struct trace_event_functions trace_stack_funcs = {
1155         .trace          = trace_stack_print,
1156 };
1157
1158 static struct trace_event trace_stack_event = {
1159         .type           = TRACE_STACK,
1160         .funcs          = &trace_stack_funcs,
1161 };
1162
1163 /* TRACE_USER_STACK */
1164 static enum print_line_t trace_user_stack_print(struct trace_iterator *iter,
1165                                                 int flags, struct trace_event *event)
1166 {
1167         struct userstack_entry *field;
1168         struct trace_seq *s = &iter->seq;
1169
1170         trace_assign_type(field, iter->ent);
1171
1172         if (!trace_seq_puts(s, "<user stack trace>\n"))
1173                 goto partial;
1174
1175         if (!seq_print_userip_objs(field, s, flags))
1176                 goto partial;
1177
1178         return TRACE_TYPE_HANDLED;
1179
1180  partial:
1181         return TRACE_TYPE_PARTIAL_LINE;
1182 }
1183
1184 static struct trace_event_functions trace_user_stack_funcs = {
1185         .trace          = trace_user_stack_print,
1186 };
1187
1188 static struct trace_event trace_user_stack_event = {
1189         .type           = TRACE_USER_STACK,
1190         .funcs          = &trace_user_stack_funcs,
1191 };
1192
1193 /* TRACE_BPRINT */
1194 static enum print_line_t
1195 trace_bprint_print(struct trace_iterator *iter, int flags,
1196                    struct trace_event *event)
1197 {
1198         struct trace_entry *entry = iter->ent;
1199         struct trace_seq *s = &iter->seq;
1200         struct bprint_entry *field;
1201
1202         trace_assign_type(field, entry);
1203
1204         if (!seq_print_ip_sym(s, field->ip, flags))
1205                 goto partial;
1206
1207         if (!trace_seq_puts(s, ": "))
1208                 goto partial;
1209
1210         if (!trace_seq_bprintf(s, field->fmt, field->buf))
1211                 goto partial;
1212
1213         return TRACE_TYPE_HANDLED;
1214
1215  partial:
1216         return TRACE_TYPE_PARTIAL_LINE;
1217 }
1218
1219
1220 static enum print_line_t
1221 trace_bprint_raw(struct trace_iterator *iter, int flags,
1222                  struct trace_event *event)
1223 {
1224         struct bprint_entry *field;
1225         struct trace_seq *s = &iter->seq;
1226
1227         trace_assign_type(field, iter->ent);
1228
1229         if (!trace_seq_printf(s, ": %lx : ", field->ip))
1230                 goto partial;
1231
1232         if (!trace_seq_bprintf(s, field->fmt, field->buf))
1233                 goto partial;
1234
1235         return TRACE_TYPE_HANDLED;
1236
1237  partial:
1238         return TRACE_TYPE_PARTIAL_LINE;
1239 }
1240
1241 static struct trace_event_functions trace_bprint_funcs = {
1242         .trace          = trace_bprint_print,
1243         .raw            = trace_bprint_raw,
1244 };
1245
1246 static struct trace_event trace_bprint_event = {
1247         .type           = TRACE_BPRINT,
1248         .funcs          = &trace_bprint_funcs,
1249 };
1250
1251 /* TRACE_PRINT */
1252 static enum print_line_t trace_print_print(struct trace_iterator *iter,
1253                                            int flags, struct trace_event *event)
1254 {
1255         struct print_entry *field;
1256         struct trace_seq *s = &iter->seq;
1257
1258         trace_assign_type(field, iter->ent);
1259
1260         if (!seq_print_ip_sym(s, field->ip, flags))
1261                 goto partial;
1262
1263         if (!trace_seq_printf(s, ": %s", field->buf))
1264                 goto partial;
1265
1266         return TRACE_TYPE_HANDLED;
1267
1268  partial:
1269         return TRACE_TYPE_PARTIAL_LINE;
1270 }
1271
1272 static enum print_line_t trace_print_raw(struct trace_iterator *iter, int flags,
1273                                          struct trace_event *event)
1274 {
1275         struct print_entry *field;
1276
1277         trace_assign_type(field, iter->ent);
1278
1279         if (!trace_seq_printf(&iter->seq, "# %lx %s", field->ip, field->buf))
1280                 goto partial;
1281
1282         return TRACE_TYPE_HANDLED;
1283
1284  partial:
1285         return TRACE_TYPE_PARTIAL_LINE;
1286 }
1287
1288 static struct trace_event_functions trace_print_funcs = {
1289         .trace          = trace_print_print,
1290         .raw            = trace_print_raw,
1291 };
1292
1293 static struct trace_event trace_print_event = {
1294         .type           = TRACE_PRINT,
1295         .funcs          = &trace_print_funcs,
1296 };
1297
1298
1299 static struct trace_event *events[] __initdata = {
1300         &trace_fn_event,
1301         &trace_ctx_event,
1302         &trace_wake_event,
1303         &trace_stack_event,
1304         &trace_user_stack_event,
1305         &trace_bprint_event,
1306         &trace_print_event,
1307         NULL
1308 };
1309
1310 __init static int init_events(void)
1311 {
1312         struct trace_event *event;
1313         int i, ret;
1314
1315         for (i = 0; events[i]; i++) {
1316                 event = events[i];
1317
1318                 ret = register_ftrace_event(event);
1319                 if (!ret) {
1320                         printk(KERN_WARNING "event %d failed to register\n",
1321                                event->type);
1322                         WARN_ON_ONCE(1);
1323                 }
1324         }
1325
1326         return 0;
1327 }
1328 device_initcall(init_events);