Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/vapier...
[cascardo/linux.git] / tools / perf / util / header.c
1 #define _FILE_OFFSET_BITS 64
2
3 #include <sys/types.h>
4 #include <byteswap.h>
5 #include <unistd.h>
6 #include <stdio.h>
7 #include <stdlib.h>
8 #include <linux/list.h>
9 #include <linux/kernel.h>
10
11 #include "evlist.h"
12 #include "evsel.h"
13 #include "util.h"
14 #include "header.h"
15 #include "../perf.h"
16 #include "trace-event.h"
17 #include "session.h"
18 #include "symbol.h"
19 #include "debug.h"
20
21 static bool no_buildid_cache = false;
22
23 static int event_count;
24 static struct perf_trace_event_type *events;
25
26 int perf_header__push_event(u64 id, const char *name)
27 {
28         if (strlen(name) > MAX_EVENT_NAME)
29                 pr_warning("Event %s will be truncated\n", name);
30
31         if (!events) {
32                 events = malloc(sizeof(struct perf_trace_event_type));
33                 if (events == NULL)
34                         return -ENOMEM;
35         } else {
36                 struct perf_trace_event_type *nevents;
37
38                 nevents = realloc(events, (event_count + 1) * sizeof(*events));
39                 if (nevents == NULL)
40                         return -ENOMEM;
41                 events = nevents;
42         }
43         memset(&events[event_count], 0, sizeof(struct perf_trace_event_type));
44         events[event_count].event_id = id;
45         strncpy(events[event_count].name, name, MAX_EVENT_NAME - 1);
46         event_count++;
47         return 0;
48 }
49
50 char *perf_header__find_event(u64 id)
51 {
52         int i;
53         for (i = 0 ; i < event_count; i++) {
54                 if (events[i].event_id == id)
55                         return events[i].name;
56         }
57         return NULL;
58 }
59
60 static const char *__perf_magic = "PERFFILE";
61
62 #define PERF_MAGIC      (*(u64 *)__perf_magic)
63
64 struct perf_file_attr {
65         struct perf_event_attr  attr;
66         struct perf_file_section        ids;
67 };
68
69 void perf_header__set_feat(struct perf_header *header, int feat)
70 {
71         set_bit(feat, header->adds_features);
72 }
73
74 void perf_header__clear_feat(struct perf_header *header, int feat)
75 {
76         clear_bit(feat, header->adds_features);
77 }
78
79 bool perf_header__has_feat(const struct perf_header *header, int feat)
80 {
81         return test_bit(feat, header->adds_features);
82 }
83
84 static int do_write(int fd, const void *buf, size_t size)
85 {
86         while (size) {
87                 int ret = write(fd, buf, size);
88
89                 if (ret < 0)
90                         return -errno;
91
92                 size -= ret;
93                 buf += ret;
94         }
95
96         return 0;
97 }
98
99 #define NAME_ALIGN 64
100
101 static int write_padded(int fd, const void *bf, size_t count,
102                         size_t count_aligned)
103 {
104         static const char zero_buf[NAME_ALIGN];
105         int err = do_write(fd, bf, count);
106
107         if (!err)
108                 err = do_write(fd, zero_buf, count_aligned - count);
109
110         return err;
111 }
112
113 #define dsos__for_each_with_build_id(pos, head) \
114         list_for_each_entry(pos, head, node)    \
115                 if (!pos->has_build_id)         \
116                         continue;               \
117                 else
118
119 static int __dsos__write_buildid_table(struct list_head *head, pid_t pid,
120                                 u16 misc, int fd)
121 {
122         struct dso *pos;
123
124         dsos__for_each_with_build_id(pos, head) {
125                 int err;
126                 struct build_id_event b;
127                 size_t len;
128
129                 if (!pos->hit)
130                         continue;
131                 len = pos->long_name_len + 1;
132                 len = ALIGN(len, NAME_ALIGN);
133                 memset(&b, 0, sizeof(b));
134                 memcpy(&b.build_id, pos->build_id, sizeof(pos->build_id));
135                 b.pid = pid;
136                 b.header.misc = misc;
137                 b.header.size = sizeof(b) + len;
138                 err = do_write(fd, &b, sizeof(b));
139                 if (err < 0)
140                         return err;
141                 err = write_padded(fd, pos->long_name,
142                                    pos->long_name_len + 1, len);
143                 if (err < 0)
144                         return err;
145         }
146
147         return 0;
148 }
149
150 static int machine__write_buildid_table(struct machine *machine, int fd)
151 {
152         int err;
153         u16 kmisc = PERF_RECORD_MISC_KERNEL,
154             umisc = PERF_RECORD_MISC_USER;
155
156         if (!machine__is_host(machine)) {
157                 kmisc = PERF_RECORD_MISC_GUEST_KERNEL;
158                 umisc = PERF_RECORD_MISC_GUEST_USER;
159         }
160
161         err = __dsos__write_buildid_table(&machine->kernel_dsos, machine->pid,
162                                           kmisc, fd);
163         if (err == 0)
164                 err = __dsos__write_buildid_table(&machine->user_dsos,
165                                                   machine->pid, umisc, fd);
166         return err;
167 }
168
169 static int dsos__write_buildid_table(struct perf_header *header, int fd)
170 {
171         struct perf_session *session = container_of(header,
172                         struct perf_session, header);
173         struct rb_node *nd;
174         int err = machine__write_buildid_table(&session->host_machine, fd);
175
176         if (err)
177                 return err;
178
179         for (nd = rb_first(&session->machines); nd; nd = rb_next(nd)) {
180                 struct machine *pos = rb_entry(nd, struct machine, rb_node);
181                 err = machine__write_buildid_table(pos, fd);
182                 if (err)
183                         break;
184         }
185         return err;
186 }
187
188 int build_id_cache__add_s(const char *sbuild_id, const char *debugdir,
189                           const char *name, bool is_kallsyms)
190 {
191         const size_t size = PATH_MAX;
192         char *realname, *filename = malloc(size),
193              *linkname = malloc(size), *targetname;
194         int len, err = -1;
195
196         if (is_kallsyms)
197                 realname = (char *)name;
198         else
199                 realname = realpath(name, NULL);
200
201         if (realname == NULL || filename == NULL || linkname == NULL)
202                 goto out_free;
203
204         len = snprintf(filename, size, "%s%s%s",
205                        debugdir, is_kallsyms ? "/" : "", realname);
206         if (mkdir_p(filename, 0755))
207                 goto out_free;
208
209         snprintf(filename + len, sizeof(filename) - len, "/%s", sbuild_id);
210
211         if (access(filename, F_OK)) {
212                 if (is_kallsyms) {
213                          if (copyfile("/proc/kallsyms", filename))
214                                 goto out_free;
215                 } else if (link(realname, filename) && copyfile(name, filename))
216                         goto out_free;
217         }
218
219         len = snprintf(linkname, size, "%s/.build-id/%.2s",
220                        debugdir, sbuild_id);
221
222         if (access(linkname, X_OK) && mkdir_p(linkname, 0755))
223                 goto out_free;
224
225         snprintf(linkname + len, size - len, "/%s", sbuild_id + 2);
226         targetname = filename + strlen(debugdir) - 5;
227         memcpy(targetname, "../..", 5);
228
229         if (symlink(targetname, linkname) == 0)
230                 err = 0;
231 out_free:
232         if (!is_kallsyms)
233                 free(realname);
234         free(filename);
235         free(linkname);
236         return err;
237 }
238
239 static int build_id_cache__add_b(const u8 *build_id, size_t build_id_size,
240                                  const char *name, const char *debugdir,
241                                  bool is_kallsyms)
242 {
243         char sbuild_id[BUILD_ID_SIZE * 2 + 1];
244
245         build_id__sprintf(build_id, build_id_size, sbuild_id);
246
247         return build_id_cache__add_s(sbuild_id, debugdir, name, is_kallsyms);
248 }
249
250 int build_id_cache__remove_s(const char *sbuild_id, const char *debugdir)
251 {
252         const size_t size = PATH_MAX;
253         char *filename = malloc(size),
254              *linkname = malloc(size);
255         int err = -1;
256
257         if (filename == NULL || linkname == NULL)
258                 goto out_free;
259
260         snprintf(linkname, size, "%s/.build-id/%.2s/%s",
261                  debugdir, sbuild_id, sbuild_id + 2);
262
263         if (access(linkname, F_OK))
264                 goto out_free;
265
266         if (readlink(linkname, filename, size) < 0)
267                 goto out_free;
268
269         if (unlink(linkname))
270                 goto out_free;
271
272         /*
273          * Since the link is relative, we must make it absolute:
274          */
275         snprintf(linkname, size, "%s/.build-id/%.2s/%s",
276                  debugdir, sbuild_id, filename);
277
278         if (unlink(linkname))
279                 goto out_free;
280
281         err = 0;
282 out_free:
283         free(filename);
284         free(linkname);
285         return err;
286 }
287
288 static int dso__cache_build_id(struct dso *dso, const char *debugdir)
289 {
290         bool is_kallsyms = dso->kernel && dso->long_name[0] != '/';
291
292         return build_id_cache__add_b(dso->build_id, sizeof(dso->build_id),
293                                      dso->long_name, debugdir, is_kallsyms);
294 }
295
296 static int __dsos__cache_build_ids(struct list_head *head, const char *debugdir)
297 {
298         struct dso *pos;
299         int err = 0;
300
301         dsos__for_each_with_build_id(pos, head)
302                 if (dso__cache_build_id(pos, debugdir))
303                         err = -1;
304
305         return err;
306 }
307
308 static int machine__cache_build_ids(struct machine *machine, const char *debugdir)
309 {
310         int ret = __dsos__cache_build_ids(&machine->kernel_dsos, debugdir);
311         ret |= __dsos__cache_build_ids(&machine->user_dsos, debugdir);
312         return ret;
313 }
314
315 static int perf_session__cache_build_ids(struct perf_session *session)
316 {
317         struct rb_node *nd;
318         int ret;
319         char debugdir[PATH_MAX];
320
321         snprintf(debugdir, sizeof(debugdir), "%s", buildid_dir);
322
323         if (mkdir(debugdir, 0755) != 0 && errno != EEXIST)
324                 return -1;
325
326         ret = machine__cache_build_ids(&session->host_machine, debugdir);
327
328         for (nd = rb_first(&session->machines); nd; nd = rb_next(nd)) {
329                 struct machine *pos = rb_entry(nd, struct machine, rb_node);
330                 ret |= machine__cache_build_ids(pos, debugdir);
331         }
332         return ret ? -1 : 0;
333 }
334
335 static bool machine__read_build_ids(struct machine *machine, bool with_hits)
336 {
337         bool ret = __dsos__read_build_ids(&machine->kernel_dsos, with_hits);
338         ret |= __dsos__read_build_ids(&machine->user_dsos, with_hits);
339         return ret;
340 }
341
342 static bool perf_session__read_build_ids(struct perf_session *session, bool with_hits)
343 {
344         struct rb_node *nd;
345         bool ret = machine__read_build_ids(&session->host_machine, with_hits);
346
347         for (nd = rb_first(&session->machines); nd; nd = rb_next(nd)) {
348                 struct machine *pos = rb_entry(nd, struct machine, rb_node);
349                 ret |= machine__read_build_ids(pos, with_hits);
350         }
351
352         return ret;
353 }
354
355 static int perf_header__adds_write(struct perf_header *header,
356                                    struct perf_evlist *evlist, int fd)
357 {
358         int nr_sections;
359         struct perf_session *session;
360         struct perf_file_section *feat_sec;
361         int sec_size;
362         u64 sec_start;
363         int idx = 0, err;
364
365         session = container_of(header, struct perf_session, header);
366
367         if (perf_header__has_feat(header, HEADER_BUILD_ID &&
368             !perf_session__read_build_ids(session, true)))
369                 perf_header__clear_feat(header, HEADER_BUILD_ID);
370
371         nr_sections = bitmap_weight(header->adds_features, HEADER_FEAT_BITS);
372         if (!nr_sections)
373                 return 0;
374
375         feat_sec = calloc(sizeof(*feat_sec), nr_sections);
376         if (feat_sec == NULL)
377                 return -ENOMEM;
378
379         sec_size = sizeof(*feat_sec) * nr_sections;
380
381         sec_start = header->data_offset + header->data_size;
382         lseek(fd, sec_start + sec_size, SEEK_SET);
383
384         if (perf_header__has_feat(header, HEADER_TRACE_INFO)) {
385                 struct perf_file_section *trace_sec;
386
387                 trace_sec = &feat_sec[idx++];
388
389                 /* Write trace info */
390                 trace_sec->offset = lseek(fd, 0, SEEK_CUR);
391                 read_tracing_data(fd, &evlist->entries);
392                 trace_sec->size = lseek(fd, 0, SEEK_CUR) - trace_sec->offset;
393         }
394
395         if (perf_header__has_feat(header, HEADER_BUILD_ID)) {
396                 struct perf_file_section *buildid_sec;
397
398                 buildid_sec = &feat_sec[idx++];
399
400                 /* Write build-ids */
401                 buildid_sec->offset = lseek(fd, 0, SEEK_CUR);
402                 err = dsos__write_buildid_table(header, fd);
403                 if (err < 0) {
404                         pr_debug("failed to write buildid table\n");
405                         goto out_free;
406                 }
407                 buildid_sec->size = lseek(fd, 0, SEEK_CUR) -
408                                           buildid_sec->offset;
409                 if (!no_buildid_cache)
410                         perf_session__cache_build_ids(session);
411         }
412
413         lseek(fd, sec_start, SEEK_SET);
414         err = do_write(fd, feat_sec, sec_size);
415         if (err < 0)
416                 pr_debug("failed to write feature section\n");
417 out_free:
418         free(feat_sec);
419         return err;
420 }
421
422 int perf_header__write_pipe(int fd)
423 {
424         struct perf_pipe_file_header f_header;
425         int err;
426
427         f_header = (struct perf_pipe_file_header){
428                 .magic     = PERF_MAGIC,
429                 .size      = sizeof(f_header),
430         };
431
432         err = do_write(fd, &f_header, sizeof(f_header));
433         if (err < 0) {
434                 pr_debug("failed to write perf pipe header\n");
435                 return err;
436         }
437
438         return 0;
439 }
440
441 int perf_session__write_header(struct perf_session *session,
442                                struct perf_evlist *evlist,
443                                int fd, bool at_exit)
444 {
445         struct perf_file_header f_header;
446         struct perf_file_attr   f_attr;
447         struct perf_header *header = &session->header;
448         struct perf_evsel *attr, *pair = NULL;
449         int err;
450
451         lseek(fd, sizeof(f_header), SEEK_SET);
452
453         if (session->evlist != evlist)
454                 pair = list_entry(session->evlist->entries.next, struct perf_evsel, node);
455
456         list_for_each_entry(attr, &evlist->entries, node) {
457                 attr->id_offset = lseek(fd, 0, SEEK_CUR);
458                 err = do_write(fd, attr->id, attr->ids * sizeof(u64));
459                 if (err < 0) {
460 out_err_write:
461                         pr_debug("failed to write perf header\n");
462                         return err;
463                 }
464                 if (session->evlist != evlist) {
465                         err = do_write(fd, pair->id, pair->ids * sizeof(u64));
466                         if (err < 0)
467                                 goto out_err_write;
468                         attr->ids += pair->ids;
469                         pair = list_entry(pair->node.next, struct perf_evsel, node);
470                 }
471         }
472
473         header->attr_offset = lseek(fd, 0, SEEK_CUR);
474
475         list_for_each_entry(attr, &evlist->entries, node) {
476                 f_attr = (struct perf_file_attr){
477                         .attr = attr->attr,
478                         .ids  = {
479                                 .offset = attr->id_offset,
480                                 .size   = attr->ids * sizeof(u64),
481                         }
482                 };
483                 err = do_write(fd, &f_attr, sizeof(f_attr));
484                 if (err < 0) {
485                         pr_debug("failed to write perf header attribute\n");
486                         return err;
487                 }
488         }
489
490         header->event_offset = lseek(fd, 0, SEEK_CUR);
491         header->event_size = event_count * sizeof(struct perf_trace_event_type);
492         if (events) {
493                 err = do_write(fd, events, header->event_size);
494                 if (err < 0) {
495                         pr_debug("failed to write perf header events\n");
496                         return err;
497                 }
498         }
499
500         header->data_offset = lseek(fd, 0, SEEK_CUR);
501
502         if (at_exit) {
503                 err = perf_header__adds_write(header, evlist, fd);
504                 if (err < 0)
505                         return err;
506         }
507
508         f_header = (struct perf_file_header){
509                 .magic     = PERF_MAGIC,
510                 .size      = sizeof(f_header),
511                 .attr_size = sizeof(f_attr),
512                 .attrs = {
513                         .offset = header->attr_offset,
514                         .size   = evlist->nr_entries * sizeof(f_attr),
515                 },
516                 .data = {
517                         .offset = header->data_offset,
518                         .size   = header->data_size,
519                 },
520                 .event_types = {
521                         .offset = header->event_offset,
522                         .size   = header->event_size,
523                 },
524         };
525
526         memcpy(&f_header.adds_features, &header->adds_features, sizeof(header->adds_features));
527
528         lseek(fd, 0, SEEK_SET);
529         err = do_write(fd, &f_header, sizeof(f_header));
530         if (err < 0) {
531                 pr_debug("failed to write perf header\n");
532                 return err;
533         }
534         lseek(fd, header->data_offset + header->data_size, SEEK_SET);
535
536         header->frozen = 1;
537         return 0;
538 }
539
540 static int perf_header__getbuffer64(struct perf_header *header,
541                                     int fd, void *buf, size_t size)
542 {
543         if (readn(fd, buf, size) <= 0)
544                 return -1;
545
546         if (header->needs_swap)
547                 mem_bswap_64(buf, size);
548
549         return 0;
550 }
551
552 int perf_header__process_sections(struct perf_header *header, int fd,
553                                   int (*process)(struct perf_file_section *section,
554                                                  struct perf_header *ph,
555                                                  int feat, int fd))
556 {
557         struct perf_file_section *feat_sec;
558         int nr_sections;
559         int sec_size;
560         int idx = 0;
561         int err = -1, feat = 1;
562
563         nr_sections = bitmap_weight(header->adds_features, HEADER_FEAT_BITS);
564         if (!nr_sections)
565                 return 0;
566
567         feat_sec = calloc(sizeof(*feat_sec), nr_sections);
568         if (!feat_sec)
569                 return -1;
570
571         sec_size = sizeof(*feat_sec) * nr_sections;
572
573         lseek(fd, header->data_offset + header->data_size, SEEK_SET);
574
575         if (perf_header__getbuffer64(header, fd, feat_sec, sec_size))
576                 goto out_free;
577
578         err = 0;
579         while (idx < nr_sections && feat < HEADER_LAST_FEATURE) {
580                 if (perf_header__has_feat(header, feat)) {
581                         struct perf_file_section *sec = &feat_sec[idx++];
582
583                         err = process(sec, header, feat, fd);
584                         if (err < 0)
585                                 break;
586                 }
587                 ++feat;
588         }
589 out_free:
590         free(feat_sec);
591         return err;
592 }
593
594 int perf_file_header__read(struct perf_file_header *header,
595                            struct perf_header *ph, int fd)
596 {
597         lseek(fd, 0, SEEK_SET);
598
599         if (readn(fd, header, sizeof(*header)) <= 0 ||
600             memcmp(&header->magic, __perf_magic, sizeof(header->magic)))
601                 return -1;
602
603         if (header->attr_size != sizeof(struct perf_file_attr)) {
604                 u64 attr_size = bswap_64(header->attr_size);
605
606                 if (attr_size != sizeof(struct perf_file_attr))
607                         return -1;
608
609                 mem_bswap_64(header, offsetof(struct perf_file_header,
610                                             adds_features));
611                 ph->needs_swap = true;
612         }
613
614         if (header->size != sizeof(*header)) {
615                 /* Support the previous format */
616                 if (header->size == offsetof(typeof(*header), adds_features))
617                         bitmap_zero(header->adds_features, HEADER_FEAT_BITS);
618                 else
619                         return -1;
620         }
621
622         memcpy(&ph->adds_features, &header->adds_features,
623                sizeof(ph->adds_features));
624         /*
625          * FIXME: hack that assumes that if we need swap the perf.data file
626          * may be coming from an arch with a different word-size, ergo different
627          * DEFINE_BITMAP format, investigate more later, but for now its mostly
628          * safe to assume that we have a build-id section. Trace files probably
629          * have several other issues in this realm anyway...
630          */
631         if (ph->needs_swap) {
632                 memset(&ph->adds_features, 0, sizeof(ph->adds_features));
633                 perf_header__set_feat(ph, HEADER_BUILD_ID);
634         }
635
636         ph->event_offset = header->event_types.offset;
637         ph->event_size   = header->event_types.size;
638         ph->data_offset  = header->data.offset;
639         ph->data_size    = header->data.size;
640         return 0;
641 }
642
643 static int __event_process_build_id(struct build_id_event *bev,
644                                     char *filename,
645                                     struct perf_session *session)
646 {
647         int err = -1;
648         struct list_head *head;
649         struct machine *machine;
650         u16 misc;
651         struct dso *dso;
652         enum dso_kernel_type dso_type;
653
654         machine = perf_session__findnew_machine(session, bev->pid);
655         if (!machine)
656                 goto out;
657
658         misc = bev->header.misc & PERF_RECORD_MISC_CPUMODE_MASK;
659
660         switch (misc) {
661         case PERF_RECORD_MISC_KERNEL:
662                 dso_type = DSO_TYPE_KERNEL;
663                 head = &machine->kernel_dsos;
664                 break;
665         case PERF_RECORD_MISC_GUEST_KERNEL:
666                 dso_type = DSO_TYPE_GUEST_KERNEL;
667                 head = &machine->kernel_dsos;
668                 break;
669         case PERF_RECORD_MISC_USER:
670         case PERF_RECORD_MISC_GUEST_USER:
671                 dso_type = DSO_TYPE_USER;
672                 head = &machine->user_dsos;
673                 break;
674         default:
675                 goto out;
676         }
677
678         dso = __dsos__findnew(head, filename);
679         if (dso != NULL) {
680                 char sbuild_id[BUILD_ID_SIZE * 2 + 1];
681
682                 dso__set_build_id(dso, &bev->build_id);
683
684                 if (filename[0] == '[')
685                         dso->kernel = dso_type;
686
687                 build_id__sprintf(dso->build_id, sizeof(dso->build_id),
688                                   sbuild_id);
689                 pr_debug("build id event received for %s: %s\n",
690                          dso->long_name, sbuild_id);
691         }
692
693         err = 0;
694 out:
695         return err;
696 }
697
698 static int perf_header__read_build_ids_abi_quirk(struct perf_header *header,
699                                                  int input, u64 offset, u64 size)
700 {
701         struct perf_session *session = container_of(header, struct perf_session, header);
702         struct {
703                 struct perf_event_header   header;
704                 u8                         build_id[ALIGN(BUILD_ID_SIZE, sizeof(u64))];
705                 char                       filename[0];
706         } old_bev;
707         struct build_id_event bev;
708         char filename[PATH_MAX];
709         u64 limit = offset + size;
710
711         while (offset < limit) {
712                 ssize_t len;
713
714                 if (read(input, &old_bev, sizeof(old_bev)) != sizeof(old_bev))
715                         return -1;
716
717                 if (header->needs_swap)
718                         perf_event_header__bswap(&old_bev.header);
719
720                 len = old_bev.header.size - sizeof(old_bev);
721                 if (read(input, filename, len) != len)
722                         return -1;
723
724                 bev.header = old_bev.header;
725                 bev.pid    = 0;
726                 memcpy(bev.build_id, old_bev.build_id, sizeof(bev.build_id));
727                 __event_process_build_id(&bev, filename, session);
728
729                 offset += bev.header.size;
730         }
731
732         return 0;
733 }
734
735 static int perf_header__read_build_ids(struct perf_header *header,
736                                        int input, u64 offset, u64 size)
737 {
738         struct perf_session *session = container_of(header, struct perf_session, header);
739         struct build_id_event bev;
740         char filename[PATH_MAX];
741         u64 limit = offset + size, orig_offset = offset;
742         int err = -1;
743
744         while (offset < limit) {
745                 ssize_t len;
746
747                 if (read(input, &bev, sizeof(bev)) != sizeof(bev))
748                         goto out;
749
750                 if (header->needs_swap)
751                         perf_event_header__bswap(&bev.header);
752
753                 len = bev.header.size - sizeof(bev);
754                 if (read(input, filename, len) != len)
755                         goto out;
756                 /*
757                  * The a1645ce1 changeset:
758                  *
759                  * "perf: 'perf kvm' tool for monitoring guest performance from host"
760                  *
761                  * Added a field to struct build_id_event that broke the file
762                  * format.
763                  *
764                  * Since the kernel build-id is the first entry, process the
765                  * table using the old format if the well known
766                  * '[kernel.kallsyms]' string for the kernel build-id has the
767                  * first 4 characters chopped off (where the pid_t sits).
768                  */
769                 if (memcmp(filename, "nel.kallsyms]", 13) == 0) {
770                         if (lseek(input, orig_offset, SEEK_SET) == (off_t)-1)
771                                 return -1;
772                         return perf_header__read_build_ids_abi_quirk(header, input, offset, size);
773                 }
774
775                 __event_process_build_id(&bev, filename, session);
776
777                 offset += bev.header.size;
778         }
779         err = 0;
780 out:
781         return err;
782 }
783
784 static int perf_file_section__process(struct perf_file_section *section,
785                                       struct perf_header *ph,
786                                       int feat, int fd)
787 {
788         if (lseek(fd, section->offset, SEEK_SET) == (off_t)-1) {
789                 pr_debug("Failed to lseek to %" PRIu64 " offset for feature "
790                           "%d, continuing...\n", section->offset, feat);
791                 return 0;
792         }
793
794         switch (feat) {
795         case HEADER_TRACE_INFO:
796                 trace_report(fd, false);
797                 break;
798
799         case HEADER_BUILD_ID:
800                 if (perf_header__read_build_ids(ph, fd, section->offset, section->size))
801                         pr_debug("Failed to read buildids, continuing...\n");
802                 break;
803         default:
804                 pr_debug("unknown feature %d, continuing...\n", feat);
805         }
806
807         return 0;
808 }
809
810 static int perf_file_header__read_pipe(struct perf_pipe_file_header *header,
811                                        struct perf_header *ph, int fd,
812                                        bool repipe)
813 {
814         if (readn(fd, header, sizeof(*header)) <= 0 ||
815             memcmp(&header->magic, __perf_magic, sizeof(header->magic)))
816                 return -1;
817
818         if (repipe && do_write(STDOUT_FILENO, header, sizeof(*header)) < 0)
819                 return -1;
820
821         if (header->size != sizeof(*header)) {
822                 u64 size = bswap_64(header->size);
823
824                 if (size != sizeof(*header))
825                         return -1;
826
827                 ph->needs_swap = true;
828         }
829
830         return 0;
831 }
832
833 static int perf_header__read_pipe(struct perf_session *session, int fd)
834 {
835         struct perf_header *header = &session->header;
836         struct perf_pipe_file_header f_header;
837
838         if (perf_file_header__read_pipe(&f_header, header, fd,
839                                         session->repipe) < 0) {
840                 pr_debug("incompatible file format\n");
841                 return -EINVAL;
842         }
843
844         session->fd = fd;
845
846         return 0;
847 }
848
849 int perf_session__read_header(struct perf_session *session, int fd)
850 {
851         struct perf_header *header = &session->header;
852         struct perf_file_header f_header;
853         struct perf_file_attr   f_attr;
854         u64                     f_id;
855         int nr_attrs, nr_ids, i, j;
856
857         session->evlist = perf_evlist__new(NULL, NULL);
858         if (session->evlist == NULL)
859                 return -ENOMEM;
860
861         if (session->fd_pipe)
862                 return perf_header__read_pipe(session, fd);
863
864         if (perf_file_header__read(&f_header, header, fd) < 0) {
865                 pr_debug("incompatible file format\n");
866                 return -EINVAL;
867         }
868
869         nr_attrs = f_header.attrs.size / sizeof(f_attr);
870         lseek(fd, f_header.attrs.offset, SEEK_SET);
871
872         for (i = 0; i < nr_attrs; i++) {
873                 struct perf_evsel *evsel;
874                 off_t tmp;
875
876                 if (perf_header__getbuffer64(header, fd, &f_attr, sizeof(f_attr)))
877                         goto out_errno;
878
879                 tmp = lseek(fd, 0, SEEK_CUR);
880                 evsel = perf_evsel__new(&f_attr.attr, i);
881
882                 if (evsel == NULL)
883                         goto out_delete_evlist;
884                 /*
885                  * Do it before so that if perf_evsel__alloc_id fails, this
886                  * entry gets purged too at perf_evlist__delete().
887                  */
888                 perf_evlist__add(session->evlist, evsel);
889
890                 nr_ids = f_attr.ids.size / sizeof(u64);
891                 /*
892                  * We don't have the cpu and thread maps on the header, so
893                  * for allocating the perf_sample_id table we fake 1 cpu and
894                  * hattr->ids threads.
895                  */
896                 if (perf_evsel__alloc_id(evsel, 1, nr_ids))
897                         goto out_delete_evlist;
898
899                 lseek(fd, f_attr.ids.offset, SEEK_SET);
900
901                 for (j = 0; j < nr_ids; j++) {
902                         if (perf_header__getbuffer64(header, fd, &f_id, sizeof(f_id)))
903                                 goto out_errno;
904
905                         perf_evlist__id_add(session->evlist, evsel, 0, j, f_id);
906                 }
907
908                 lseek(fd, tmp, SEEK_SET);
909         }
910
911         if (f_header.event_types.size) {
912                 lseek(fd, f_header.event_types.offset, SEEK_SET);
913                 events = malloc(f_header.event_types.size);
914                 if (events == NULL)
915                         return -ENOMEM;
916                 if (perf_header__getbuffer64(header, fd, events,
917                                              f_header.event_types.size))
918                         goto out_errno;
919                 event_count =  f_header.event_types.size / sizeof(struct perf_trace_event_type);
920         }
921
922         perf_header__process_sections(header, fd, perf_file_section__process);
923
924         lseek(fd, header->data_offset, SEEK_SET);
925
926         header->frozen = 1;
927         return 0;
928 out_errno:
929         return -errno;
930
931 out_delete_evlist:
932         perf_evlist__delete(session->evlist);
933         session->evlist = NULL;
934         return -ENOMEM;
935 }
936
937 u64 perf_evlist__sample_type(struct perf_evlist *evlist)
938 {
939         struct perf_evsel *pos;
940         u64 type = 0;
941
942         list_for_each_entry(pos, &evlist->entries, node) {
943                 if (!type)
944                         type = pos->attr.sample_type;
945                 else if (type != pos->attr.sample_type)
946                         die("non matching sample_type");
947         }
948
949         return type;
950 }
951
952 bool perf_evlist__sample_id_all(const struct perf_evlist *evlist)
953 {
954         bool value = false, first = true;
955         struct perf_evsel *pos;
956
957         list_for_each_entry(pos, &evlist->entries, node) {
958                 if (first) {
959                         value = pos->attr.sample_id_all;
960                         first = false;
961                 } else if (value != pos->attr.sample_id_all)
962                         die("non matching sample_id_all");
963         }
964
965         return value;
966 }
967
968 int perf_event__synthesize_attr(struct perf_event_attr *attr, u16 ids, u64 *id,
969                                 perf_event__handler_t process,
970                                 struct perf_session *session)
971 {
972         union perf_event *ev;
973         size_t size;
974         int err;
975
976         size = sizeof(struct perf_event_attr);
977         size = ALIGN(size, sizeof(u64));
978         size += sizeof(struct perf_event_header);
979         size += ids * sizeof(u64);
980
981         ev = malloc(size);
982
983         if (ev == NULL)
984                 return -ENOMEM;
985
986         ev->attr.attr = *attr;
987         memcpy(ev->attr.id, id, ids * sizeof(u64));
988
989         ev->attr.header.type = PERF_RECORD_HEADER_ATTR;
990         ev->attr.header.size = size;
991
992         err = process(ev, NULL, session);
993
994         free(ev);
995
996         return err;
997 }
998
999 int perf_session__synthesize_attrs(struct perf_session *session,
1000                                    perf_event__handler_t process)
1001 {
1002         struct perf_evsel *attr;
1003         int err = 0;
1004
1005         list_for_each_entry(attr, &session->evlist->entries, node) {
1006                 err = perf_event__synthesize_attr(&attr->attr, attr->ids,
1007                                                   attr->id, process, session);
1008                 if (err) {
1009                         pr_debug("failed to create perf header attribute\n");
1010                         return err;
1011                 }
1012         }
1013
1014         return err;
1015 }
1016
1017 int perf_event__process_attr(union perf_event *event,
1018                              struct perf_session *session)
1019 {
1020         unsigned int i, ids, n_ids;
1021         struct perf_evsel *evsel;
1022
1023         if (session->evlist == NULL) {
1024                 session->evlist = perf_evlist__new(NULL, NULL);
1025                 if (session->evlist == NULL)
1026                         return -ENOMEM;
1027         }
1028
1029         evsel = perf_evsel__new(&event->attr.attr,
1030                                 session->evlist->nr_entries);
1031         if (evsel == NULL)
1032                 return -ENOMEM;
1033
1034         perf_evlist__add(session->evlist, evsel);
1035
1036         ids = event->header.size;
1037         ids -= (void *)&event->attr.id - (void *)event;
1038         n_ids = ids / sizeof(u64);
1039         /*
1040          * We don't have the cpu and thread maps on the header, so
1041          * for allocating the perf_sample_id table we fake 1 cpu and
1042          * hattr->ids threads.
1043          */
1044         if (perf_evsel__alloc_id(evsel, 1, n_ids))
1045                 return -ENOMEM;
1046
1047         for (i = 0; i < n_ids; i++) {
1048                 perf_evlist__id_add(session->evlist, evsel, 0, i,
1049                                     event->attr.id[i]);
1050         }
1051
1052         perf_session__update_sample_type(session);
1053
1054         return 0;
1055 }
1056
1057 int perf_event__synthesize_event_type(u64 event_id, char *name,
1058                                       perf_event__handler_t process,
1059                                       struct perf_session *session)
1060 {
1061         union perf_event ev;
1062         size_t size = 0;
1063         int err = 0;
1064
1065         memset(&ev, 0, sizeof(ev));
1066
1067         ev.event_type.event_type.event_id = event_id;
1068         memset(ev.event_type.event_type.name, 0, MAX_EVENT_NAME);
1069         strncpy(ev.event_type.event_type.name, name, MAX_EVENT_NAME - 1);
1070
1071         ev.event_type.header.type = PERF_RECORD_HEADER_EVENT_TYPE;
1072         size = strlen(name);
1073         size = ALIGN(size, sizeof(u64));
1074         ev.event_type.header.size = sizeof(ev.event_type) -
1075                 (sizeof(ev.event_type.event_type.name) - size);
1076
1077         err = process(&ev, NULL, session);
1078
1079         return err;
1080 }
1081
1082 int perf_event__synthesize_event_types(perf_event__handler_t process,
1083                                        struct perf_session *session)
1084 {
1085         struct perf_trace_event_type *type;
1086         int i, err = 0;
1087
1088         for (i = 0; i < event_count; i++) {
1089                 type = &events[i];
1090
1091                 err = perf_event__synthesize_event_type(type->event_id,
1092                                                         type->name, process,
1093                                                         session);
1094                 if (err) {
1095                         pr_debug("failed to create perf header event type\n");
1096                         return err;
1097                 }
1098         }
1099
1100         return err;
1101 }
1102
1103 int perf_event__process_event_type(union perf_event *event,
1104                                    struct perf_session *session __unused)
1105 {
1106         if (perf_header__push_event(event->event_type.event_type.event_id,
1107                                     event->event_type.event_type.name) < 0)
1108                 return -ENOMEM;
1109
1110         return 0;
1111 }
1112
1113 int perf_event__synthesize_tracing_data(int fd, struct perf_evlist *evlist,
1114                                          perf_event__handler_t process,
1115                                    struct perf_session *session __unused)
1116 {
1117         union perf_event ev;
1118         ssize_t size = 0, aligned_size = 0, padding;
1119         int err __used = 0;
1120
1121         memset(&ev, 0, sizeof(ev));
1122
1123         ev.tracing_data.header.type = PERF_RECORD_HEADER_TRACING_DATA;
1124         size = read_tracing_data_size(fd, &evlist->entries);
1125         if (size <= 0)
1126                 return size;
1127         aligned_size = ALIGN(size, sizeof(u64));
1128         padding = aligned_size - size;
1129         ev.tracing_data.header.size = sizeof(ev.tracing_data);
1130         ev.tracing_data.size = aligned_size;
1131
1132         process(&ev, NULL, session);
1133
1134         err = read_tracing_data(fd, &evlist->entries);
1135         write_padded(fd, NULL, 0, padding);
1136
1137         return aligned_size;
1138 }
1139
1140 int perf_event__process_tracing_data(union perf_event *event,
1141                                      struct perf_session *session)
1142 {
1143         ssize_t size_read, padding, size = event->tracing_data.size;
1144         off_t offset = lseek(session->fd, 0, SEEK_CUR);
1145         char buf[BUFSIZ];
1146
1147         /* setup for reading amidst mmap */
1148         lseek(session->fd, offset + sizeof(struct tracing_data_event),
1149               SEEK_SET);
1150
1151         size_read = trace_report(session->fd, session->repipe);
1152
1153         padding = ALIGN(size_read, sizeof(u64)) - size_read;
1154
1155         if (read(session->fd, buf, padding) < 0)
1156                 die("reading input file");
1157         if (session->repipe) {
1158                 int retw = write(STDOUT_FILENO, buf, padding);
1159                 if (retw <= 0 || retw != padding)
1160                         die("repiping tracing data padding");
1161         }
1162
1163         if (size_read + padding != size)
1164                 die("tracing data size mismatch");
1165
1166         return size_read + padding;
1167 }
1168
1169 int perf_event__synthesize_build_id(struct dso *pos, u16 misc,
1170                                     perf_event__handler_t process,
1171                                     struct machine *machine,
1172                                     struct perf_session *session)
1173 {
1174         union perf_event ev;
1175         size_t len;
1176         int err = 0;
1177
1178         if (!pos->hit)
1179                 return err;
1180
1181         memset(&ev, 0, sizeof(ev));
1182
1183         len = pos->long_name_len + 1;
1184         len = ALIGN(len, NAME_ALIGN);
1185         memcpy(&ev.build_id.build_id, pos->build_id, sizeof(pos->build_id));
1186         ev.build_id.header.type = PERF_RECORD_HEADER_BUILD_ID;
1187         ev.build_id.header.misc = misc;
1188         ev.build_id.pid = machine->pid;
1189         ev.build_id.header.size = sizeof(ev.build_id) + len;
1190         memcpy(&ev.build_id.filename, pos->long_name, pos->long_name_len);
1191
1192         err = process(&ev, NULL, session);
1193
1194         return err;
1195 }
1196
1197 int perf_event__process_build_id(union perf_event *event,
1198                                  struct perf_session *session)
1199 {
1200         __event_process_build_id(&event->build_id,
1201                                  event->build_id.filename,
1202                                  session);
1203         return 0;
1204 }
1205
1206 void disable_buildid_cache(void)
1207 {
1208         no_buildid_cache = true;
1209 }