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perf tools: Handle failure case in trace_report()
[~andy/linux] / tools / perf / util / header.c
1 #include "util.h"
2 #include <sys/types.h>
3 #include <byteswap.h>
4 #include <unistd.h>
5 #include <stdio.h>
6 #include <stdlib.h>
7 #include <linux/list.h>
8 #include <linux/kernel.h>
9 #include <linux/bitops.h>
10 #include <sys/utsname.h>
11
12 #include "evlist.h"
13 #include "evsel.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 #include "cpumap.h"
21 #include "pmu.h"
22 #include "vdso.h"
23 #include "strbuf.h"
24 #include "build-id.h"
25
26 static bool no_buildid_cache = false;
27
28 static int trace_event_count;
29 static struct perf_trace_event_type *trace_events;
30
31 static u32 header_argc;
32 static const char **header_argv;
33
34 int perf_header__push_event(u64 id, const char *name)
35 {
36         struct perf_trace_event_type *nevents;
37
38         if (strlen(name) > MAX_EVENT_NAME)
39                 pr_warning("Event %s will be truncated\n", name);
40
41         nevents = realloc(trace_events, (trace_event_count + 1) * sizeof(*trace_events));
42         if (nevents == NULL)
43                 return -ENOMEM;
44         trace_events = nevents;
45
46         memset(&trace_events[trace_event_count], 0, sizeof(struct perf_trace_event_type));
47         trace_events[trace_event_count].event_id = id;
48         strncpy(trace_events[trace_event_count].name, name, MAX_EVENT_NAME - 1);
49         trace_event_count++;
50         return 0;
51 }
52
53 char *perf_header__find_event(u64 id)
54 {
55         int i;
56         for (i = 0 ; i < trace_event_count; i++) {
57                 if (trace_events[i].event_id == id)
58                         return trace_events[i].name;
59         }
60         return NULL;
61 }
62
63 /*
64  * magic2 = "PERFILE2"
65  * must be a numerical value to let the endianness
66  * determine the memory layout. That way we are able
67  * to detect endianness when reading the perf.data file
68  * back.
69  *
70  * we check for legacy (PERFFILE) format.
71  */
72 static const char *__perf_magic1 = "PERFFILE";
73 static const u64 __perf_magic2    = 0x32454c4946524550ULL;
74 static const u64 __perf_magic2_sw = 0x50455246494c4532ULL;
75
76 #define PERF_MAGIC      __perf_magic2
77
78 struct perf_file_attr {
79         struct perf_event_attr  attr;
80         struct perf_file_section        ids;
81 };
82
83 void perf_header__set_feat(struct perf_header *header, int feat)
84 {
85         set_bit(feat, header->adds_features);
86 }
87
88 void perf_header__clear_feat(struct perf_header *header, int feat)
89 {
90         clear_bit(feat, header->adds_features);
91 }
92
93 bool perf_header__has_feat(const struct perf_header *header, int feat)
94 {
95         return test_bit(feat, header->adds_features);
96 }
97
98 static int do_write(int fd, const void *buf, size_t size)
99 {
100         while (size) {
101                 int ret = write(fd, buf, size);
102
103                 if (ret < 0)
104                         return -errno;
105
106                 size -= ret;
107                 buf += ret;
108         }
109
110         return 0;
111 }
112
113 #define NAME_ALIGN 64
114
115 static int write_padded(int fd, const void *bf, size_t count,
116                         size_t count_aligned)
117 {
118         static const char zero_buf[NAME_ALIGN];
119         int err = do_write(fd, bf, count);
120
121         if (!err)
122                 err = do_write(fd, zero_buf, count_aligned - count);
123
124         return err;
125 }
126
127 static int do_write_string(int fd, const char *str)
128 {
129         u32 len, olen;
130         int ret;
131
132         olen = strlen(str) + 1;
133         len = PERF_ALIGN(olen, NAME_ALIGN);
134
135         /* write len, incl. \0 */
136         ret = do_write(fd, &len, sizeof(len));
137         if (ret < 0)
138                 return ret;
139
140         return write_padded(fd, str, olen, len);
141 }
142
143 static char *do_read_string(int fd, struct perf_header *ph)
144 {
145         ssize_t sz, ret;
146         u32 len;
147         char *buf;
148
149         sz = readn(fd, &len, sizeof(len));
150         if (sz < (ssize_t)sizeof(len))
151                 return NULL;
152
153         if (ph->needs_swap)
154                 len = bswap_32(len);
155
156         buf = malloc(len);
157         if (!buf)
158                 return NULL;
159
160         ret = readn(fd, buf, len);
161         if (ret == (ssize_t)len) {
162                 /*
163                  * strings are padded by zeroes
164                  * thus the actual strlen of buf
165                  * may be less than len
166                  */
167                 return buf;
168         }
169
170         free(buf);
171         return NULL;
172 }
173
174 int
175 perf_header__set_cmdline(int argc, const char **argv)
176 {
177         int i;
178
179         /*
180          * If header_argv has already been set, do not override it.
181          * This allows a command to set the cmdline, parse args and
182          * then call another builtin function that implements a
183          * command -- e.g, cmd_kvm calling cmd_record.
184          */
185         if (header_argv)
186                 return 0;
187
188         header_argc = (u32)argc;
189
190         /* do not include NULL termination */
191         header_argv = calloc(argc, sizeof(char *));
192         if (!header_argv)
193                 return -ENOMEM;
194
195         /*
196          * must copy argv contents because it gets moved
197          * around during option parsing
198          */
199         for (i = 0; i < argc ; i++)
200                 header_argv[i] = argv[i];
201
202         return 0;
203 }
204
205 #define dsos__for_each_with_build_id(pos, head) \
206         list_for_each_entry(pos, head, node)    \
207                 if (!pos->has_build_id)         \
208                         continue;               \
209                 else
210
211 static int write_buildid(char *name, size_t name_len, u8 *build_id,
212                          pid_t pid, u16 misc, int fd)
213 {
214         int err;
215         struct build_id_event b;
216         size_t len;
217
218         len = name_len + 1;
219         len = PERF_ALIGN(len, NAME_ALIGN);
220
221         memset(&b, 0, sizeof(b));
222         memcpy(&b.build_id, build_id, BUILD_ID_SIZE);
223         b.pid = pid;
224         b.header.misc = misc;
225         b.header.size = sizeof(b) + len;
226
227         err = do_write(fd, &b, sizeof(b));
228         if (err < 0)
229                 return err;
230
231         return write_padded(fd, name, name_len + 1, len);
232 }
233
234 static int __dsos__write_buildid_table(struct list_head *head, pid_t pid,
235                                 u16 misc, int fd)
236 {
237         struct dso *pos;
238
239         dsos__for_each_with_build_id(pos, head) {
240                 int err;
241                 char  *name;
242                 size_t name_len;
243
244                 if (!pos->hit)
245                         continue;
246
247                 if (is_vdso_map(pos->short_name)) {
248                         name = (char *) VDSO__MAP_NAME;
249                         name_len = sizeof(VDSO__MAP_NAME) + 1;
250                 } else {
251                         name = pos->long_name;
252                         name_len = pos->long_name_len + 1;
253                 }
254
255                 err = write_buildid(name, name_len, pos->build_id,
256                                     pid, misc, fd);
257                 if (err)
258                         return err;
259         }
260
261         return 0;
262 }
263
264 static int machine__write_buildid_table(struct machine *machine, int fd)
265 {
266         int err;
267         u16 kmisc = PERF_RECORD_MISC_KERNEL,
268             umisc = PERF_RECORD_MISC_USER;
269
270         if (!machine__is_host(machine)) {
271                 kmisc = PERF_RECORD_MISC_GUEST_KERNEL;
272                 umisc = PERF_RECORD_MISC_GUEST_USER;
273         }
274
275         err = __dsos__write_buildid_table(&machine->kernel_dsos, machine->pid,
276                                           kmisc, fd);
277         if (err == 0)
278                 err = __dsos__write_buildid_table(&machine->user_dsos,
279                                                   machine->pid, umisc, fd);
280         return err;
281 }
282
283 static int dsos__write_buildid_table(struct perf_header *header, int fd)
284 {
285         struct perf_session *session = container_of(header,
286                         struct perf_session, header);
287         struct rb_node *nd;
288         int err = machine__write_buildid_table(&session->machines.host, fd);
289
290         if (err)
291                 return err;
292
293         for (nd = rb_first(&session->machines.guests); nd; nd = rb_next(nd)) {
294                 struct machine *pos = rb_entry(nd, struct machine, rb_node);
295                 err = machine__write_buildid_table(pos, fd);
296                 if (err)
297                         break;
298         }
299         return err;
300 }
301
302 int build_id_cache__add_s(const char *sbuild_id, const char *debugdir,
303                           const char *name, bool is_kallsyms, bool is_vdso)
304 {
305         const size_t size = PATH_MAX;
306         char *realname, *filename = zalloc(size),
307              *linkname = zalloc(size), *targetname;
308         int len, err = -1;
309         bool slash = is_kallsyms || is_vdso;
310
311         if (is_kallsyms) {
312                 if (symbol_conf.kptr_restrict) {
313                         pr_debug("Not caching a kptr_restrict'ed /proc/kallsyms\n");
314                         err = 0;
315                         goto out_free;
316                 }
317                 realname = (char *) name;
318         } else
319                 realname = realpath(name, NULL);
320
321         if (realname == NULL || filename == NULL || linkname == NULL)
322                 goto out_free;
323
324         len = scnprintf(filename, size, "%s%s%s",
325                        debugdir, slash ? "/" : "",
326                        is_vdso ? VDSO__MAP_NAME : realname);
327         if (mkdir_p(filename, 0755))
328                 goto out_free;
329
330         snprintf(filename + len, size - len, "/%s", sbuild_id);
331
332         if (access(filename, F_OK)) {
333                 if (is_kallsyms) {
334                          if (copyfile("/proc/kallsyms", filename))
335                                 goto out_free;
336                 } else if (link(realname, filename) && copyfile(name, filename))
337                         goto out_free;
338         }
339
340         len = scnprintf(linkname, size, "%s/.build-id/%.2s",
341                        debugdir, sbuild_id);
342
343         if (access(linkname, X_OK) && mkdir_p(linkname, 0755))
344                 goto out_free;
345
346         snprintf(linkname + len, size - len, "/%s", sbuild_id + 2);
347         targetname = filename + strlen(debugdir) - 5;
348         memcpy(targetname, "../..", 5);
349
350         if (symlink(targetname, linkname) == 0)
351                 err = 0;
352 out_free:
353         if (!is_kallsyms)
354                 free(realname);
355         free(filename);
356         free(linkname);
357         return err;
358 }
359
360 static int build_id_cache__add_b(const u8 *build_id, size_t build_id_size,
361                                  const char *name, const char *debugdir,
362                                  bool is_kallsyms, bool is_vdso)
363 {
364         char sbuild_id[BUILD_ID_SIZE * 2 + 1];
365
366         build_id__sprintf(build_id, build_id_size, sbuild_id);
367
368         return build_id_cache__add_s(sbuild_id, debugdir, name,
369                                      is_kallsyms, is_vdso);
370 }
371
372 int build_id_cache__remove_s(const char *sbuild_id, const char *debugdir)
373 {
374         const size_t size = PATH_MAX;
375         char *filename = zalloc(size),
376              *linkname = zalloc(size);
377         int err = -1;
378
379         if (filename == NULL || linkname == NULL)
380                 goto out_free;
381
382         snprintf(linkname, size, "%s/.build-id/%.2s/%s",
383                  debugdir, sbuild_id, sbuild_id + 2);
384
385         if (access(linkname, F_OK))
386                 goto out_free;
387
388         if (readlink(linkname, filename, size - 1) < 0)
389                 goto out_free;
390
391         if (unlink(linkname))
392                 goto out_free;
393
394         /*
395          * Since the link is relative, we must make it absolute:
396          */
397         snprintf(linkname, size, "%s/.build-id/%.2s/%s",
398                  debugdir, sbuild_id, filename);
399
400         if (unlink(linkname))
401                 goto out_free;
402
403         err = 0;
404 out_free:
405         free(filename);
406         free(linkname);
407         return err;
408 }
409
410 static int dso__cache_build_id(struct dso *dso, const char *debugdir)
411 {
412         bool is_kallsyms = dso->kernel && dso->long_name[0] != '/';
413         bool is_vdso = is_vdso_map(dso->short_name);
414
415         return build_id_cache__add_b(dso->build_id, sizeof(dso->build_id),
416                                      dso->long_name, debugdir,
417                                      is_kallsyms, is_vdso);
418 }
419
420 static int __dsos__cache_build_ids(struct list_head *head, const char *debugdir)
421 {
422         struct dso *pos;
423         int err = 0;
424
425         dsos__for_each_with_build_id(pos, head)
426                 if (dso__cache_build_id(pos, debugdir))
427                         err = -1;
428
429         return err;
430 }
431
432 static int machine__cache_build_ids(struct machine *machine, const char *debugdir)
433 {
434         int ret = __dsos__cache_build_ids(&machine->kernel_dsos, debugdir);
435         ret |= __dsos__cache_build_ids(&machine->user_dsos, debugdir);
436         return ret;
437 }
438
439 static int perf_session__cache_build_ids(struct perf_session *session)
440 {
441         struct rb_node *nd;
442         int ret;
443         char debugdir[PATH_MAX];
444
445         snprintf(debugdir, sizeof(debugdir), "%s", buildid_dir);
446
447         if (mkdir(debugdir, 0755) != 0 && errno != EEXIST)
448                 return -1;
449
450         ret = machine__cache_build_ids(&session->machines.host, debugdir);
451
452         for (nd = rb_first(&session->machines.guests); nd; nd = rb_next(nd)) {
453                 struct machine *pos = rb_entry(nd, struct machine, rb_node);
454                 ret |= machine__cache_build_ids(pos, debugdir);
455         }
456         return ret ? -1 : 0;
457 }
458
459 static bool machine__read_build_ids(struct machine *machine, bool with_hits)
460 {
461         bool ret = __dsos__read_build_ids(&machine->kernel_dsos, with_hits);
462         ret |= __dsos__read_build_ids(&machine->user_dsos, with_hits);
463         return ret;
464 }
465
466 static bool perf_session__read_build_ids(struct perf_session *session, bool with_hits)
467 {
468         struct rb_node *nd;
469         bool ret = machine__read_build_ids(&session->machines.host, with_hits);
470
471         for (nd = rb_first(&session->machines.guests); nd; nd = rb_next(nd)) {
472                 struct machine *pos = rb_entry(nd, struct machine, rb_node);
473                 ret |= machine__read_build_ids(pos, with_hits);
474         }
475
476         return ret;
477 }
478
479 static int write_tracing_data(int fd, struct perf_header *h __maybe_unused,
480                             struct perf_evlist *evlist)
481 {
482         return read_tracing_data(fd, &evlist->entries);
483 }
484
485
486 static int write_build_id(int fd, struct perf_header *h,
487                           struct perf_evlist *evlist __maybe_unused)
488 {
489         struct perf_session *session;
490         int err;
491
492         session = container_of(h, struct perf_session, header);
493
494         if (!perf_session__read_build_ids(session, true))
495                 return -1;
496
497         err = dsos__write_buildid_table(h, fd);
498         if (err < 0) {
499                 pr_debug("failed to write buildid table\n");
500                 return err;
501         }
502         if (!no_buildid_cache)
503                 perf_session__cache_build_ids(session);
504
505         return 0;
506 }
507
508 static int write_hostname(int fd, struct perf_header *h __maybe_unused,
509                           struct perf_evlist *evlist __maybe_unused)
510 {
511         struct utsname uts;
512         int ret;
513
514         ret = uname(&uts);
515         if (ret < 0)
516                 return -1;
517
518         return do_write_string(fd, uts.nodename);
519 }
520
521 static int write_osrelease(int fd, struct perf_header *h __maybe_unused,
522                            struct perf_evlist *evlist __maybe_unused)
523 {
524         struct utsname uts;
525         int ret;
526
527         ret = uname(&uts);
528         if (ret < 0)
529                 return -1;
530
531         return do_write_string(fd, uts.release);
532 }
533
534 static int write_arch(int fd, struct perf_header *h __maybe_unused,
535                       struct perf_evlist *evlist __maybe_unused)
536 {
537         struct utsname uts;
538         int ret;
539
540         ret = uname(&uts);
541         if (ret < 0)
542                 return -1;
543
544         return do_write_string(fd, uts.machine);
545 }
546
547 static int write_version(int fd, struct perf_header *h __maybe_unused,
548                          struct perf_evlist *evlist __maybe_unused)
549 {
550         return do_write_string(fd, perf_version_string);
551 }
552
553 static int write_cpudesc(int fd, struct perf_header *h __maybe_unused,
554                        struct perf_evlist *evlist __maybe_unused)
555 {
556 #ifndef CPUINFO_PROC
557 #define CPUINFO_PROC NULL
558 #endif
559         FILE *file;
560         char *buf = NULL;
561         char *s, *p;
562         const char *search = CPUINFO_PROC;
563         size_t len = 0;
564         int ret = -1;
565
566         if (!search)
567                 return -1;
568
569         file = fopen("/proc/cpuinfo", "r");
570         if (!file)
571                 return -1;
572
573         while (getline(&buf, &len, file) > 0) {
574                 ret = strncmp(buf, search, strlen(search));
575                 if (!ret)
576                         break;
577         }
578
579         if (ret)
580                 goto done;
581
582         s = buf;
583
584         p = strchr(buf, ':');
585         if (p && *(p+1) == ' ' && *(p+2))
586                 s = p + 2;
587         p = strchr(s, '\n');
588         if (p)
589                 *p = '\0';
590
591         /* squash extra space characters (branding string) */
592         p = s;
593         while (*p) {
594                 if (isspace(*p)) {
595                         char *r = p + 1;
596                         char *q = r;
597                         *p = ' ';
598                         while (*q && isspace(*q))
599                                 q++;
600                         if (q != (p+1))
601                                 while ((*r++ = *q++));
602                 }
603                 p++;
604         }
605         ret = do_write_string(fd, s);
606 done:
607         free(buf);
608         fclose(file);
609         return ret;
610 }
611
612 static int write_nrcpus(int fd, struct perf_header *h __maybe_unused,
613                         struct perf_evlist *evlist __maybe_unused)
614 {
615         long nr;
616         u32 nrc, nra;
617         int ret;
618
619         nr = sysconf(_SC_NPROCESSORS_CONF);
620         if (nr < 0)
621                 return -1;
622
623         nrc = (u32)(nr & UINT_MAX);
624
625         nr = sysconf(_SC_NPROCESSORS_ONLN);
626         if (nr < 0)
627                 return -1;
628
629         nra = (u32)(nr & UINT_MAX);
630
631         ret = do_write(fd, &nrc, sizeof(nrc));
632         if (ret < 0)
633                 return ret;
634
635         return do_write(fd, &nra, sizeof(nra));
636 }
637
638 static int write_event_desc(int fd, struct perf_header *h __maybe_unused,
639                             struct perf_evlist *evlist)
640 {
641         struct perf_evsel *evsel;
642         u32 nre, nri, sz;
643         int ret;
644
645         nre = evlist->nr_entries;
646
647         /*
648          * write number of events
649          */
650         ret = do_write(fd, &nre, sizeof(nre));
651         if (ret < 0)
652                 return ret;
653
654         /*
655          * size of perf_event_attr struct
656          */
657         sz = (u32)sizeof(evsel->attr);
658         ret = do_write(fd, &sz, sizeof(sz));
659         if (ret < 0)
660                 return ret;
661
662         list_for_each_entry(evsel, &evlist->entries, node) {
663
664                 ret = do_write(fd, &evsel->attr, sz);
665                 if (ret < 0)
666                         return ret;
667                 /*
668                  * write number of unique id per event
669                  * there is one id per instance of an event
670                  *
671                  * copy into an nri to be independent of the
672                  * type of ids,
673                  */
674                 nri = evsel->ids;
675                 ret = do_write(fd, &nri, sizeof(nri));
676                 if (ret < 0)
677                         return ret;
678
679                 /*
680                  * write event string as passed on cmdline
681                  */
682                 ret = do_write_string(fd, perf_evsel__name(evsel));
683                 if (ret < 0)
684                         return ret;
685                 /*
686                  * write unique ids for this event
687                  */
688                 ret = do_write(fd, evsel->id, evsel->ids * sizeof(u64));
689                 if (ret < 0)
690                         return ret;
691         }
692         return 0;
693 }
694
695 static int write_cmdline(int fd, struct perf_header *h __maybe_unused,
696                          struct perf_evlist *evlist __maybe_unused)
697 {
698         char buf[MAXPATHLEN];
699         char proc[32];
700         u32 i, n;
701         int ret;
702
703         /*
704          * actual atual path to perf binary
705          */
706         sprintf(proc, "/proc/%d/exe", getpid());
707         ret = readlink(proc, buf, sizeof(buf));
708         if (ret <= 0)
709                 return -1;
710
711         /* readlink() does not add null termination */
712         buf[ret] = '\0';
713
714         /* account for binary path */
715         n = header_argc + 1;
716
717         ret = do_write(fd, &n, sizeof(n));
718         if (ret < 0)
719                 return ret;
720
721         ret = do_write_string(fd, buf);
722         if (ret < 0)
723                 return ret;
724
725         for (i = 0 ; i < header_argc; i++) {
726                 ret = do_write_string(fd, header_argv[i]);
727                 if (ret < 0)
728                         return ret;
729         }
730         return 0;
731 }
732
733 #define CORE_SIB_FMT \
734         "/sys/devices/system/cpu/cpu%d/topology/core_siblings_list"
735 #define THRD_SIB_FMT \
736         "/sys/devices/system/cpu/cpu%d/topology/thread_siblings_list"
737
738 struct cpu_topo {
739         u32 core_sib;
740         u32 thread_sib;
741         char **core_siblings;
742         char **thread_siblings;
743 };
744
745 static int build_cpu_topo(struct cpu_topo *tp, int cpu)
746 {
747         FILE *fp;
748         char filename[MAXPATHLEN];
749         char *buf = NULL, *p;
750         size_t len = 0;
751         u32 i = 0;
752         int ret = -1;
753
754         sprintf(filename, CORE_SIB_FMT, cpu);
755         fp = fopen(filename, "r");
756         if (!fp)
757                 return -1;
758
759         if (getline(&buf, &len, fp) <= 0)
760                 goto done;
761
762         fclose(fp);
763
764         p = strchr(buf, '\n');
765         if (p)
766                 *p = '\0';
767
768         for (i = 0; i < tp->core_sib; i++) {
769                 if (!strcmp(buf, tp->core_siblings[i]))
770                         break;
771         }
772         if (i == tp->core_sib) {
773                 tp->core_siblings[i] = buf;
774                 tp->core_sib++;
775                 buf = NULL;
776                 len = 0;
777         }
778
779         sprintf(filename, THRD_SIB_FMT, cpu);
780         fp = fopen(filename, "r");
781         if (!fp)
782                 goto done;
783
784         if (getline(&buf, &len, fp) <= 0)
785                 goto done;
786
787         p = strchr(buf, '\n');
788         if (p)
789                 *p = '\0';
790
791         for (i = 0; i < tp->thread_sib; i++) {
792                 if (!strcmp(buf, tp->thread_siblings[i]))
793                         break;
794         }
795         if (i == tp->thread_sib) {
796                 tp->thread_siblings[i] = buf;
797                 tp->thread_sib++;
798                 buf = NULL;
799         }
800         ret = 0;
801 done:
802         if(fp)
803                 fclose(fp);
804         free(buf);
805         return ret;
806 }
807
808 static void free_cpu_topo(struct cpu_topo *tp)
809 {
810         u32 i;
811
812         if (!tp)
813                 return;
814
815         for (i = 0 ; i < tp->core_sib; i++)
816                 free(tp->core_siblings[i]);
817
818         for (i = 0 ; i < tp->thread_sib; i++)
819                 free(tp->thread_siblings[i]);
820
821         free(tp);
822 }
823
824 static struct cpu_topo *build_cpu_topology(void)
825 {
826         struct cpu_topo *tp;
827         void *addr;
828         u32 nr, i;
829         size_t sz;
830         long ncpus;
831         int ret = -1;
832
833         ncpus = sysconf(_SC_NPROCESSORS_CONF);
834         if (ncpus < 0)
835                 return NULL;
836
837         nr = (u32)(ncpus & UINT_MAX);
838
839         sz = nr * sizeof(char *);
840
841         addr = calloc(1, sizeof(*tp) + 2 * sz);
842         if (!addr)
843                 return NULL;
844
845         tp = addr;
846
847         addr += sizeof(*tp);
848         tp->core_siblings = addr;
849         addr += sz;
850         tp->thread_siblings = addr;
851
852         for (i = 0; i < nr; i++) {
853                 ret = build_cpu_topo(tp, i);
854                 if (ret < 0)
855                         break;
856         }
857         if (ret) {
858                 free_cpu_topo(tp);
859                 tp = NULL;
860         }
861         return tp;
862 }
863
864 static int write_cpu_topology(int fd, struct perf_header *h __maybe_unused,
865                           struct perf_evlist *evlist __maybe_unused)
866 {
867         struct cpu_topo *tp;
868         u32 i;
869         int ret;
870
871         tp = build_cpu_topology();
872         if (!tp)
873                 return -1;
874
875         ret = do_write(fd, &tp->core_sib, sizeof(tp->core_sib));
876         if (ret < 0)
877                 goto done;
878
879         for (i = 0; i < tp->core_sib; i++) {
880                 ret = do_write_string(fd, tp->core_siblings[i]);
881                 if (ret < 0)
882                         goto done;
883         }
884         ret = do_write(fd, &tp->thread_sib, sizeof(tp->thread_sib));
885         if (ret < 0)
886                 goto done;
887
888         for (i = 0; i < tp->thread_sib; i++) {
889                 ret = do_write_string(fd, tp->thread_siblings[i]);
890                 if (ret < 0)
891                         break;
892         }
893 done:
894         free_cpu_topo(tp);
895         return ret;
896 }
897
898
899
900 static int write_total_mem(int fd, struct perf_header *h __maybe_unused,
901                           struct perf_evlist *evlist __maybe_unused)
902 {
903         char *buf = NULL;
904         FILE *fp;
905         size_t len = 0;
906         int ret = -1, n;
907         uint64_t mem;
908
909         fp = fopen("/proc/meminfo", "r");
910         if (!fp)
911                 return -1;
912
913         while (getline(&buf, &len, fp) > 0) {
914                 ret = strncmp(buf, "MemTotal:", 9);
915                 if (!ret)
916                         break;
917         }
918         if (!ret) {
919                 n = sscanf(buf, "%*s %"PRIu64, &mem);
920                 if (n == 1)
921                         ret = do_write(fd, &mem, sizeof(mem));
922         }
923         free(buf);
924         fclose(fp);
925         return ret;
926 }
927
928 static int write_topo_node(int fd, int node)
929 {
930         char str[MAXPATHLEN];
931         char field[32];
932         char *buf = NULL, *p;
933         size_t len = 0;
934         FILE *fp;
935         u64 mem_total, mem_free, mem;
936         int ret = -1;
937
938         sprintf(str, "/sys/devices/system/node/node%d/meminfo", node);
939         fp = fopen(str, "r");
940         if (!fp)
941                 return -1;
942
943         while (getline(&buf, &len, fp) > 0) {
944                 /* skip over invalid lines */
945                 if (!strchr(buf, ':'))
946                         continue;
947                 if (sscanf(buf, "%*s %*d %s %"PRIu64, field, &mem) != 2)
948                         goto done;
949                 if (!strcmp(field, "MemTotal:"))
950                         mem_total = mem;
951                 if (!strcmp(field, "MemFree:"))
952                         mem_free = mem;
953         }
954
955         fclose(fp);
956         fp = NULL;
957
958         ret = do_write(fd, &mem_total, sizeof(u64));
959         if (ret)
960                 goto done;
961
962         ret = do_write(fd, &mem_free, sizeof(u64));
963         if (ret)
964                 goto done;
965
966         ret = -1;
967         sprintf(str, "/sys/devices/system/node/node%d/cpulist", node);
968
969         fp = fopen(str, "r");
970         if (!fp)
971                 goto done;
972
973         if (getline(&buf, &len, fp) <= 0)
974                 goto done;
975
976         p = strchr(buf, '\n');
977         if (p)
978                 *p = '\0';
979
980         ret = do_write_string(fd, buf);
981 done:
982         free(buf);
983         if (fp)
984                 fclose(fp);
985         return ret;
986 }
987
988 static int write_numa_topology(int fd, struct perf_header *h __maybe_unused,
989                           struct perf_evlist *evlist __maybe_unused)
990 {
991         char *buf = NULL;
992         size_t len = 0;
993         FILE *fp;
994         struct cpu_map *node_map = NULL;
995         char *c;
996         u32 nr, i, j;
997         int ret = -1;
998
999         fp = fopen("/sys/devices/system/node/online", "r");
1000         if (!fp)
1001                 return -1;
1002
1003         if (getline(&buf, &len, fp) <= 0)
1004                 goto done;
1005
1006         c = strchr(buf, '\n');
1007         if (c)
1008                 *c = '\0';
1009
1010         node_map = cpu_map__new(buf);
1011         if (!node_map)
1012                 goto done;
1013
1014         nr = (u32)node_map->nr;
1015
1016         ret = do_write(fd, &nr, sizeof(nr));
1017         if (ret < 0)
1018                 goto done;
1019
1020         for (i = 0; i < nr; i++) {
1021                 j = (u32)node_map->map[i];
1022                 ret = do_write(fd, &j, sizeof(j));
1023                 if (ret < 0)
1024                         break;
1025
1026                 ret = write_topo_node(fd, i);
1027                 if (ret < 0)
1028                         break;
1029         }
1030 done:
1031         free(buf);
1032         fclose(fp);
1033         free(node_map);
1034         return ret;
1035 }
1036
1037 /*
1038  * File format:
1039  *
1040  * struct pmu_mappings {
1041  *      u32     pmu_num;
1042  *      struct pmu_map {
1043  *              u32     type;
1044  *              char    name[];
1045  *      }[pmu_num];
1046  * };
1047  */
1048
1049 static int write_pmu_mappings(int fd, struct perf_header *h __maybe_unused,
1050                               struct perf_evlist *evlist __maybe_unused)
1051 {
1052         struct perf_pmu *pmu = NULL;
1053         off_t offset = lseek(fd, 0, SEEK_CUR);
1054         __u32 pmu_num = 0;
1055         int ret;
1056
1057         /* write real pmu_num later */
1058         ret = do_write(fd, &pmu_num, sizeof(pmu_num));
1059         if (ret < 0)
1060                 return ret;
1061
1062         while ((pmu = perf_pmu__scan(pmu))) {
1063                 if (!pmu->name)
1064                         continue;
1065                 pmu_num++;
1066
1067                 ret = do_write(fd, &pmu->type, sizeof(pmu->type));
1068                 if (ret < 0)
1069                         return ret;
1070
1071                 ret = do_write_string(fd, pmu->name);
1072                 if (ret < 0)
1073                         return ret;
1074         }
1075
1076         if (pwrite(fd, &pmu_num, sizeof(pmu_num), offset) != sizeof(pmu_num)) {
1077                 /* discard all */
1078                 lseek(fd, offset, SEEK_SET);
1079                 return -1;
1080         }
1081
1082         return 0;
1083 }
1084
1085 /*
1086  * File format:
1087  *
1088  * struct group_descs {
1089  *      u32     nr_groups;
1090  *      struct group_desc {
1091  *              char    name[];
1092  *              u32     leader_idx;
1093  *              u32     nr_members;
1094  *      }[nr_groups];
1095  * };
1096  */
1097 static int write_group_desc(int fd, struct perf_header *h __maybe_unused,
1098                             struct perf_evlist *evlist)
1099 {
1100         u32 nr_groups = evlist->nr_groups;
1101         struct perf_evsel *evsel;
1102         int ret;
1103
1104         ret = do_write(fd, &nr_groups, sizeof(nr_groups));
1105         if (ret < 0)
1106                 return ret;
1107
1108         list_for_each_entry(evsel, &evlist->entries, node) {
1109                 if (perf_evsel__is_group_leader(evsel) &&
1110                     evsel->nr_members > 1) {
1111                         const char *name = evsel->group_name ?: "{anon_group}";
1112                         u32 leader_idx = evsel->idx;
1113                         u32 nr_members = evsel->nr_members;
1114
1115                         ret = do_write_string(fd, name);
1116                         if (ret < 0)
1117                                 return ret;
1118
1119                         ret = do_write(fd, &leader_idx, sizeof(leader_idx));
1120                         if (ret < 0)
1121                                 return ret;
1122
1123                         ret = do_write(fd, &nr_members, sizeof(nr_members));
1124                         if (ret < 0)
1125                                 return ret;
1126                 }
1127         }
1128         return 0;
1129 }
1130
1131 /*
1132  * default get_cpuid(): nothing gets recorded
1133  * actual implementation must be in arch/$(ARCH)/util/header.c
1134  */
1135 int __attribute__ ((weak)) get_cpuid(char *buffer __maybe_unused,
1136                                      size_t sz __maybe_unused)
1137 {
1138         return -1;
1139 }
1140
1141 static int write_cpuid(int fd, struct perf_header *h __maybe_unused,
1142                        struct perf_evlist *evlist __maybe_unused)
1143 {
1144         char buffer[64];
1145         int ret;
1146
1147         ret = get_cpuid(buffer, sizeof(buffer));
1148         if (!ret)
1149                 goto write_it;
1150
1151         return -1;
1152 write_it:
1153         return do_write_string(fd, buffer);
1154 }
1155
1156 static int write_branch_stack(int fd __maybe_unused,
1157                               struct perf_header *h __maybe_unused,
1158                        struct perf_evlist *evlist __maybe_unused)
1159 {
1160         return 0;
1161 }
1162
1163 static void print_hostname(struct perf_header *ph, int fd __maybe_unused,
1164                            FILE *fp)
1165 {
1166         fprintf(fp, "# hostname : %s\n", ph->env.hostname);
1167 }
1168
1169 static void print_osrelease(struct perf_header *ph, int fd __maybe_unused,
1170                             FILE *fp)
1171 {
1172         fprintf(fp, "# os release : %s\n", ph->env.os_release);
1173 }
1174
1175 static void print_arch(struct perf_header *ph, int fd __maybe_unused, FILE *fp)
1176 {
1177         fprintf(fp, "# arch : %s\n", ph->env.arch);
1178 }
1179
1180 static void print_cpudesc(struct perf_header *ph, int fd __maybe_unused,
1181                           FILE *fp)
1182 {
1183         fprintf(fp, "# cpudesc : %s\n", ph->env.cpu_desc);
1184 }
1185
1186 static void print_nrcpus(struct perf_header *ph, int fd __maybe_unused,
1187                          FILE *fp)
1188 {
1189         fprintf(fp, "# nrcpus online : %u\n", ph->env.nr_cpus_online);
1190         fprintf(fp, "# nrcpus avail : %u\n", ph->env.nr_cpus_avail);
1191 }
1192
1193 static void print_version(struct perf_header *ph, int fd __maybe_unused,
1194                           FILE *fp)
1195 {
1196         fprintf(fp, "# perf version : %s\n", ph->env.version);
1197 }
1198
1199 static void print_cmdline(struct perf_header *ph, int fd __maybe_unused,
1200                           FILE *fp)
1201 {
1202         int nr, i;
1203         char *str;
1204
1205         nr = ph->env.nr_cmdline;
1206         str = ph->env.cmdline;
1207
1208         fprintf(fp, "# cmdline : ");
1209
1210         for (i = 0; i < nr; i++) {
1211                 fprintf(fp, "%s ", str);
1212                 str += strlen(str) + 1;
1213         }
1214         fputc('\n', fp);
1215 }
1216
1217 static void print_cpu_topology(struct perf_header *ph, int fd __maybe_unused,
1218                                FILE *fp)
1219 {
1220         int nr, i;
1221         char *str;
1222
1223         nr = ph->env.nr_sibling_cores;
1224         str = ph->env.sibling_cores;
1225
1226         for (i = 0; i < nr; i++) {
1227                 fprintf(fp, "# sibling cores   : %s\n", str);
1228                 str += strlen(str) + 1;
1229         }
1230
1231         nr = ph->env.nr_sibling_threads;
1232         str = ph->env.sibling_threads;
1233
1234         for (i = 0; i < nr; i++) {
1235                 fprintf(fp, "# sibling threads : %s\n", str);
1236                 str += strlen(str) + 1;
1237         }
1238 }
1239
1240 static void free_event_desc(struct perf_evsel *events)
1241 {
1242         struct perf_evsel *evsel;
1243
1244         if (!events)
1245                 return;
1246
1247         for (evsel = events; evsel->attr.size; evsel++) {
1248                 if (evsel->name)
1249                         free(evsel->name);
1250                 if (evsel->id)
1251                         free(evsel->id);
1252         }
1253
1254         free(events);
1255 }
1256
1257 static struct perf_evsel *
1258 read_event_desc(struct perf_header *ph, int fd)
1259 {
1260         struct perf_evsel *evsel, *events = NULL;
1261         u64 *id;
1262         void *buf = NULL;
1263         u32 nre, sz, nr, i, j;
1264         ssize_t ret;
1265         size_t msz;
1266
1267         /* number of events */
1268         ret = readn(fd, &nre, sizeof(nre));
1269         if (ret != (ssize_t)sizeof(nre))
1270                 goto error;
1271
1272         if (ph->needs_swap)
1273                 nre = bswap_32(nre);
1274
1275         ret = readn(fd, &sz, sizeof(sz));
1276         if (ret != (ssize_t)sizeof(sz))
1277                 goto error;
1278
1279         if (ph->needs_swap)
1280                 sz = bswap_32(sz);
1281
1282         /* buffer to hold on file attr struct */
1283         buf = malloc(sz);
1284         if (!buf)
1285                 goto error;
1286
1287         /* the last event terminates with evsel->attr.size == 0: */
1288         events = calloc(nre + 1, sizeof(*events));
1289         if (!events)
1290                 goto error;
1291
1292         msz = sizeof(evsel->attr);
1293         if (sz < msz)
1294                 msz = sz;
1295
1296         for (i = 0, evsel = events; i < nre; evsel++, i++) {
1297                 evsel->idx = i;
1298
1299                 /*
1300                  * must read entire on-file attr struct to
1301                  * sync up with layout.
1302                  */
1303                 ret = readn(fd, buf, sz);
1304                 if (ret != (ssize_t)sz)
1305                         goto error;
1306
1307                 if (ph->needs_swap)
1308                         perf_event__attr_swap(buf);
1309
1310                 memcpy(&evsel->attr, buf, msz);
1311
1312                 ret = readn(fd, &nr, sizeof(nr));
1313                 if (ret != (ssize_t)sizeof(nr))
1314                         goto error;
1315
1316                 if (ph->needs_swap) {
1317                         nr = bswap_32(nr);
1318                         evsel->needs_swap = true;
1319                 }
1320
1321                 evsel->name = do_read_string(fd, ph);
1322
1323                 if (!nr)
1324                         continue;
1325
1326                 id = calloc(nr, sizeof(*id));
1327                 if (!id)
1328                         goto error;
1329                 evsel->ids = nr;
1330                 evsel->id = id;
1331
1332                 for (j = 0 ; j < nr; j++) {
1333                         ret = readn(fd, id, sizeof(*id));
1334                         if (ret != (ssize_t)sizeof(*id))
1335                                 goto error;
1336                         if (ph->needs_swap)
1337                                 *id = bswap_64(*id);
1338                         id++;
1339                 }
1340         }
1341 out:
1342         if (buf)
1343                 free(buf);
1344         return events;
1345 error:
1346         if (events)
1347                 free_event_desc(events);
1348         events = NULL;
1349         goto out;
1350 }
1351
1352 static void print_event_desc(struct perf_header *ph, int fd, FILE *fp)
1353 {
1354         struct perf_evsel *evsel, *events = read_event_desc(ph, fd);
1355         u32 j;
1356         u64 *id;
1357
1358         if (!events) {
1359                 fprintf(fp, "# event desc: not available or unable to read\n");
1360                 return;
1361         }
1362
1363         for (evsel = events; evsel->attr.size; evsel++) {
1364                 fprintf(fp, "# event : name = %s, ", evsel->name);
1365
1366                 fprintf(fp, "type = %d, config = 0x%"PRIx64
1367                             ", config1 = 0x%"PRIx64", config2 = 0x%"PRIx64,
1368                                 evsel->attr.type,
1369                                 (u64)evsel->attr.config,
1370                                 (u64)evsel->attr.config1,
1371                                 (u64)evsel->attr.config2);
1372
1373                 fprintf(fp, ", excl_usr = %d, excl_kern = %d",
1374                                 evsel->attr.exclude_user,
1375                                 evsel->attr.exclude_kernel);
1376
1377                 fprintf(fp, ", excl_host = %d, excl_guest = %d",
1378                                 evsel->attr.exclude_host,
1379                                 evsel->attr.exclude_guest);
1380
1381                 fprintf(fp, ", precise_ip = %d", evsel->attr.precise_ip);
1382
1383                 if (evsel->ids) {
1384                         fprintf(fp, ", id = {");
1385                         for (j = 0, id = evsel->id; j < evsel->ids; j++, id++) {
1386                                 if (j)
1387                                         fputc(',', fp);
1388                                 fprintf(fp, " %"PRIu64, *id);
1389                         }
1390                         fprintf(fp, " }");
1391                 }
1392
1393                 fputc('\n', fp);
1394         }
1395
1396         free_event_desc(events);
1397 }
1398
1399 static void print_total_mem(struct perf_header *ph, int fd __maybe_unused,
1400                             FILE *fp)
1401 {
1402         fprintf(fp, "# total memory : %Lu kB\n", ph->env.total_mem);
1403 }
1404
1405 static void print_numa_topology(struct perf_header *ph, int fd __maybe_unused,
1406                                 FILE *fp)
1407 {
1408         u32 nr, c, i;
1409         char *str, *tmp;
1410         uint64_t mem_total, mem_free;
1411
1412         /* nr nodes */
1413         nr = ph->env.nr_numa_nodes;
1414         str = ph->env.numa_nodes;
1415
1416         for (i = 0; i < nr; i++) {
1417                 /* node number */
1418                 c = strtoul(str, &tmp, 0);
1419                 if (*tmp != ':')
1420                         goto error;
1421
1422                 str = tmp + 1;
1423                 mem_total = strtoull(str, &tmp, 0);
1424                 if (*tmp != ':')
1425                         goto error;
1426
1427                 str = tmp + 1;
1428                 mem_free = strtoull(str, &tmp, 0);
1429                 if (*tmp != ':')
1430                         goto error;
1431
1432                 fprintf(fp, "# node%u meminfo  : total = %"PRIu64" kB,"
1433                             " free = %"PRIu64" kB\n",
1434                         c, mem_total, mem_free);
1435
1436                 str = tmp + 1;
1437                 fprintf(fp, "# node%u cpu list : %s\n", c, str);
1438
1439                 str += strlen(str) + 1;
1440         }
1441         return;
1442 error:
1443         fprintf(fp, "# numa topology : not available\n");
1444 }
1445
1446 static void print_cpuid(struct perf_header *ph, int fd __maybe_unused, FILE *fp)
1447 {
1448         fprintf(fp, "# cpuid : %s\n", ph->env.cpuid);
1449 }
1450
1451 static void print_branch_stack(struct perf_header *ph __maybe_unused,
1452                                int fd __maybe_unused, FILE *fp)
1453 {
1454         fprintf(fp, "# contains samples with branch stack\n");
1455 }
1456
1457 static void print_pmu_mappings(struct perf_header *ph, int fd __maybe_unused,
1458                                FILE *fp)
1459 {
1460         const char *delimiter = "# pmu mappings: ";
1461         char *str, *tmp;
1462         u32 pmu_num;
1463         u32 type;
1464
1465         pmu_num = ph->env.nr_pmu_mappings;
1466         if (!pmu_num) {
1467                 fprintf(fp, "# pmu mappings: not available\n");
1468                 return;
1469         }
1470
1471         str = ph->env.pmu_mappings;
1472
1473         while (pmu_num) {
1474                 type = strtoul(str, &tmp, 0);
1475                 if (*tmp != ':')
1476                         goto error;
1477
1478                 str = tmp + 1;
1479                 fprintf(fp, "%s%s = %" PRIu32, delimiter, str, type);
1480
1481                 delimiter = ", ";
1482                 str += strlen(str) + 1;
1483                 pmu_num--;
1484         }
1485
1486         fprintf(fp, "\n");
1487
1488         if (!pmu_num)
1489                 return;
1490 error:
1491         fprintf(fp, "# pmu mappings: unable to read\n");
1492 }
1493
1494 static void print_group_desc(struct perf_header *ph, int fd __maybe_unused,
1495                              FILE *fp)
1496 {
1497         struct perf_session *session;
1498         struct perf_evsel *evsel;
1499         u32 nr = 0;
1500
1501         session = container_of(ph, struct perf_session, header);
1502
1503         list_for_each_entry(evsel, &session->evlist->entries, node) {
1504                 if (perf_evsel__is_group_leader(evsel) &&
1505                     evsel->nr_members > 1) {
1506                         fprintf(fp, "# group: %s{%s", evsel->group_name ?: "",
1507                                 perf_evsel__name(evsel));
1508
1509                         nr = evsel->nr_members - 1;
1510                 } else if (nr) {
1511                         fprintf(fp, ",%s", perf_evsel__name(evsel));
1512
1513                         if (--nr == 0)
1514                                 fprintf(fp, "}\n");
1515                 }
1516         }
1517 }
1518
1519 static int __event_process_build_id(struct build_id_event *bev,
1520                                     char *filename,
1521                                     struct perf_session *session)
1522 {
1523         int err = -1;
1524         struct list_head *head;
1525         struct machine *machine;
1526         u16 misc;
1527         struct dso *dso;
1528         enum dso_kernel_type dso_type;
1529
1530         machine = perf_session__findnew_machine(session, bev->pid);
1531         if (!machine)
1532                 goto out;
1533
1534         misc = bev->header.misc & PERF_RECORD_MISC_CPUMODE_MASK;
1535
1536         switch (misc) {
1537         case PERF_RECORD_MISC_KERNEL:
1538                 dso_type = DSO_TYPE_KERNEL;
1539                 head = &machine->kernel_dsos;
1540                 break;
1541         case PERF_RECORD_MISC_GUEST_KERNEL:
1542                 dso_type = DSO_TYPE_GUEST_KERNEL;
1543                 head = &machine->kernel_dsos;
1544                 break;
1545         case PERF_RECORD_MISC_USER:
1546         case PERF_RECORD_MISC_GUEST_USER:
1547                 dso_type = DSO_TYPE_USER;
1548                 head = &machine->user_dsos;
1549                 break;
1550         default:
1551                 goto out;
1552         }
1553
1554         dso = __dsos__findnew(head, filename);
1555         if (dso != NULL) {
1556                 char sbuild_id[BUILD_ID_SIZE * 2 + 1];
1557
1558                 dso__set_build_id(dso, &bev->build_id);
1559
1560                 if (filename[0] == '[')
1561                         dso->kernel = dso_type;
1562
1563                 build_id__sprintf(dso->build_id, sizeof(dso->build_id),
1564                                   sbuild_id);
1565                 pr_debug("build id event received for %s: %s\n",
1566                          dso->long_name, sbuild_id);
1567         }
1568
1569         err = 0;
1570 out:
1571         return err;
1572 }
1573
1574 static int perf_header__read_build_ids_abi_quirk(struct perf_header *header,
1575                                                  int input, u64 offset, u64 size)
1576 {
1577         struct perf_session *session = container_of(header, struct perf_session, header);
1578         struct {
1579                 struct perf_event_header   header;
1580                 u8                         build_id[PERF_ALIGN(BUILD_ID_SIZE, sizeof(u64))];
1581                 char                       filename[0];
1582         } old_bev;
1583         struct build_id_event bev;
1584         char filename[PATH_MAX];
1585         u64 limit = offset + size;
1586
1587         while (offset < limit) {
1588                 ssize_t len;
1589
1590                 if (readn(input, &old_bev, sizeof(old_bev)) != sizeof(old_bev))
1591                         return -1;
1592
1593                 if (header->needs_swap)
1594                         perf_event_header__bswap(&old_bev.header);
1595
1596                 len = old_bev.header.size - sizeof(old_bev);
1597                 if (readn(input, filename, len) != len)
1598                         return -1;
1599
1600                 bev.header = old_bev.header;
1601
1602                 /*
1603                  * As the pid is the missing value, we need to fill
1604                  * it properly. The header.misc value give us nice hint.
1605                  */
1606                 bev.pid = HOST_KERNEL_ID;
1607                 if (bev.header.misc == PERF_RECORD_MISC_GUEST_USER ||
1608                     bev.header.misc == PERF_RECORD_MISC_GUEST_KERNEL)
1609                         bev.pid = DEFAULT_GUEST_KERNEL_ID;
1610
1611                 memcpy(bev.build_id, old_bev.build_id, sizeof(bev.build_id));
1612                 __event_process_build_id(&bev, filename, session);
1613
1614                 offset += bev.header.size;
1615         }
1616
1617         return 0;
1618 }
1619
1620 static int perf_header__read_build_ids(struct perf_header *header,
1621                                        int input, u64 offset, u64 size)
1622 {
1623         struct perf_session *session = container_of(header, struct perf_session, header);
1624         struct build_id_event bev;
1625         char filename[PATH_MAX];
1626         u64 limit = offset + size, orig_offset = offset;
1627         int err = -1;
1628
1629         while (offset < limit) {
1630                 ssize_t len;
1631
1632                 if (readn(input, &bev, sizeof(bev)) != sizeof(bev))
1633                         goto out;
1634
1635                 if (header->needs_swap)
1636                         perf_event_header__bswap(&bev.header);
1637
1638                 len = bev.header.size - sizeof(bev);
1639                 if (readn(input, filename, len) != len)
1640                         goto out;
1641                 /*
1642                  * The a1645ce1 changeset:
1643                  *
1644                  * "perf: 'perf kvm' tool for monitoring guest performance from host"
1645                  *
1646                  * Added a field to struct build_id_event that broke the file
1647                  * format.
1648                  *
1649                  * Since the kernel build-id is the first entry, process the
1650                  * table using the old format if the well known
1651                  * '[kernel.kallsyms]' string for the kernel build-id has the
1652                  * first 4 characters chopped off (where the pid_t sits).
1653                  */
1654                 if (memcmp(filename, "nel.kallsyms]", 13) == 0) {
1655                         if (lseek(input, orig_offset, SEEK_SET) == (off_t)-1)
1656                                 return -1;
1657                         return perf_header__read_build_ids_abi_quirk(header, input, offset, size);
1658                 }
1659
1660                 __event_process_build_id(&bev, filename, session);
1661
1662                 offset += bev.header.size;
1663         }
1664         err = 0;
1665 out:
1666         return err;
1667 }
1668
1669 static int process_tracing_data(struct perf_file_section *section __maybe_unused,
1670                                 struct perf_header *ph __maybe_unused,
1671                                 int fd, void *data)
1672 {
1673         ssize_t ret = trace_report(fd, data, false);
1674         return ret < 0 ? -1 : 0;
1675 }
1676
1677 static int process_build_id(struct perf_file_section *section,
1678                             struct perf_header *ph, int fd,
1679                             void *data __maybe_unused)
1680 {
1681         if (perf_header__read_build_ids(ph, fd, section->offset, section->size))
1682                 pr_debug("Failed to read buildids, continuing...\n");
1683         return 0;
1684 }
1685
1686 static int process_hostname(struct perf_file_section *section __maybe_unused,
1687                             struct perf_header *ph, int fd,
1688                             void *data __maybe_unused)
1689 {
1690         ph->env.hostname = do_read_string(fd, ph);
1691         return ph->env.hostname ? 0 : -ENOMEM;
1692 }
1693
1694 static int process_osrelease(struct perf_file_section *section __maybe_unused,
1695                              struct perf_header *ph, int fd,
1696                              void *data __maybe_unused)
1697 {
1698         ph->env.os_release = do_read_string(fd, ph);
1699         return ph->env.os_release ? 0 : -ENOMEM;
1700 }
1701
1702 static int process_version(struct perf_file_section *section __maybe_unused,
1703                            struct perf_header *ph, int fd,
1704                            void *data __maybe_unused)
1705 {
1706         ph->env.version = do_read_string(fd, ph);
1707         return ph->env.version ? 0 : -ENOMEM;
1708 }
1709
1710 static int process_arch(struct perf_file_section *section __maybe_unused,
1711                         struct perf_header *ph, int fd,
1712                         void *data __maybe_unused)
1713 {
1714         ph->env.arch = do_read_string(fd, ph);
1715         return ph->env.arch ? 0 : -ENOMEM;
1716 }
1717
1718 static int process_nrcpus(struct perf_file_section *section __maybe_unused,
1719                           struct perf_header *ph, int fd,
1720                           void *data __maybe_unused)
1721 {
1722         size_t ret;
1723         u32 nr;
1724
1725         ret = readn(fd, &nr, sizeof(nr));
1726         if (ret != sizeof(nr))
1727                 return -1;
1728
1729         if (ph->needs_swap)
1730                 nr = bswap_32(nr);
1731
1732         ph->env.nr_cpus_online = nr;
1733
1734         ret = readn(fd, &nr, sizeof(nr));
1735         if (ret != sizeof(nr))
1736                 return -1;
1737
1738         if (ph->needs_swap)
1739                 nr = bswap_32(nr);
1740
1741         ph->env.nr_cpus_avail = nr;
1742         return 0;
1743 }
1744
1745 static int process_cpudesc(struct perf_file_section *section __maybe_unused,
1746                            struct perf_header *ph, int fd,
1747                            void *data __maybe_unused)
1748 {
1749         ph->env.cpu_desc = do_read_string(fd, ph);
1750         return ph->env.cpu_desc ? 0 : -ENOMEM;
1751 }
1752
1753 static int process_cpuid(struct perf_file_section *section __maybe_unused,
1754                          struct perf_header *ph,  int fd,
1755                          void *data __maybe_unused)
1756 {
1757         ph->env.cpuid = do_read_string(fd, ph);
1758         return ph->env.cpuid ? 0 : -ENOMEM;
1759 }
1760
1761 static int process_total_mem(struct perf_file_section *section __maybe_unused,
1762                              struct perf_header *ph, int fd,
1763                              void *data __maybe_unused)
1764 {
1765         uint64_t mem;
1766         size_t ret;
1767
1768         ret = readn(fd, &mem, sizeof(mem));
1769         if (ret != sizeof(mem))
1770                 return -1;
1771
1772         if (ph->needs_swap)
1773                 mem = bswap_64(mem);
1774
1775         ph->env.total_mem = mem;
1776         return 0;
1777 }
1778
1779 static struct perf_evsel *
1780 perf_evlist__find_by_index(struct perf_evlist *evlist, int idx)
1781 {
1782         struct perf_evsel *evsel;
1783
1784         list_for_each_entry(evsel, &evlist->entries, node) {
1785                 if (evsel->idx == idx)
1786                         return evsel;
1787         }
1788
1789         return NULL;
1790 }
1791
1792 static void
1793 perf_evlist__set_event_name(struct perf_evlist *evlist,
1794                             struct perf_evsel *event)
1795 {
1796         struct perf_evsel *evsel;
1797
1798         if (!event->name)
1799                 return;
1800
1801         evsel = perf_evlist__find_by_index(evlist, event->idx);
1802         if (!evsel)
1803                 return;
1804
1805         if (evsel->name)
1806                 return;
1807
1808         evsel->name = strdup(event->name);
1809 }
1810
1811 static int
1812 process_event_desc(struct perf_file_section *section __maybe_unused,
1813                    struct perf_header *header, int fd,
1814                    void *data __maybe_unused)
1815 {
1816         struct perf_session *session;
1817         struct perf_evsel *evsel, *events = read_event_desc(header, fd);
1818
1819         if (!events)
1820                 return 0;
1821
1822         session = container_of(header, struct perf_session, header);
1823         for (evsel = events; evsel->attr.size; evsel++)
1824                 perf_evlist__set_event_name(session->evlist, evsel);
1825
1826         free_event_desc(events);
1827
1828         return 0;
1829 }
1830
1831 static int process_cmdline(struct perf_file_section *section __maybe_unused,
1832                            struct perf_header *ph, int fd,
1833                            void *data __maybe_unused)
1834 {
1835         size_t ret;
1836         char *str;
1837         u32 nr, i;
1838         struct strbuf sb;
1839
1840         ret = readn(fd, &nr, sizeof(nr));
1841         if (ret != sizeof(nr))
1842                 return -1;
1843
1844         if (ph->needs_swap)
1845                 nr = bswap_32(nr);
1846
1847         ph->env.nr_cmdline = nr;
1848         strbuf_init(&sb, 128);
1849
1850         for (i = 0; i < nr; i++) {
1851                 str = do_read_string(fd, ph);
1852                 if (!str)
1853                         goto error;
1854
1855                 /* include a NULL character at the end */
1856                 strbuf_add(&sb, str, strlen(str) + 1);
1857                 free(str);
1858         }
1859         ph->env.cmdline = strbuf_detach(&sb, NULL);
1860         return 0;
1861
1862 error:
1863         strbuf_release(&sb);
1864         return -1;
1865 }
1866
1867 static int process_cpu_topology(struct perf_file_section *section __maybe_unused,
1868                                 struct perf_header *ph, int fd,
1869                                 void *data __maybe_unused)
1870 {
1871         size_t ret;
1872         u32 nr, i;
1873         char *str;
1874         struct strbuf sb;
1875
1876         ret = readn(fd, &nr, sizeof(nr));
1877         if (ret != sizeof(nr))
1878                 return -1;
1879
1880         if (ph->needs_swap)
1881                 nr = bswap_32(nr);
1882
1883         ph->env.nr_sibling_cores = nr;
1884         strbuf_init(&sb, 128);
1885
1886         for (i = 0; i < nr; i++) {
1887                 str = do_read_string(fd, ph);
1888                 if (!str)
1889                         goto error;
1890
1891                 /* include a NULL character at the end */
1892                 strbuf_add(&sb, str, strlen(str) + 1);
1893                 free(str);
1894         }
1895         ph->env.sibling_cores = strbuf_detach(&sb, NULL);
1896
1897         ret = readn(fd, &nr, sizeof(nr));
1898         if (ret != sizeof(nr))
1899                 return -1;
1900
1901         if (ph->needs_swap)
1902                 nr = bswap_32(nr);
1903
1904         ph->env.nr_sibling_threads = nr;
1905
1906         for (i = 0; i < nr; i++) {
1907                 str = do_read_string(fd, ph);
1908                 if (!str)
1909                         goto error;
1910
1911                 /* include a NULL character at the end */
1912                 strbuf_add(&sb, str, strlen(str) + 1);
1913                 free(str);
1914         }
1915         ph->env.sibling_threads = strbuf_detach(&sb, NULL);
1916         return 0;
1917
1918 error:
1919         strbuf_release(&sb);
1920         return -1;
1921 }
1922
1923 static int process_numa_topology(struct perf_file_section *section __maybe_unused,
1924                                  struct perf_header *ph, int fd,
1925                                  void *data __maybe_unused)
1926 {
1927         size_t ret;
1928         u32 nr, node, i;
1929         char *str;
1930         uint64_t mem_total, mem_free;
1931         struct strbuf sb;
1932
1933         /* nr nodes */
1934         ret = readn(fd, &nr, sizeof(nr));
1935         if (ret != sizeof(nr))
1936                 goto error;
1937
1938         if (ph->needs_swap)
1939                 nr = bswap_32(nr);
1940
1941         ph->env.nr_numa_nodes = nr;
1942         strbuf_init(&sb, 256);
1943
1944         for (i = 0; i < nr; i++) {
1945                 /* node number */
1946                 ret = readn(fd, &node, sizeof(node));
1947                 if (ret != sizeof(node))
1948                         goto error;
1949
1950                 ret = readn(fd, &mem_total, sizeof(u64));
1951                 if (ret != sizeof(u64))
1952                         goto error;
1953
1954                 ret = readn(fd, &mem_free, sizeof(u64));
1955                 if (ret != sizeof(u64))
1956                         goto error;
1957
1958                 if (ph->needs_swap) {
1959                         node = bswap_32(node);
1960                         mem_total = bswap_64(mem_total);
1961                         mem_free = bswap_64(mem_free);
1962                 }
1963
1964                 strbuf_addf(&sb, "%u:%"PRIu64":%"PRIu64":",
1965                             node, mem_total, mem_free);
1966
1967                 str = do_read_string(fd, ph);
1968                 if (!str)
1969                         goto error;
1970
1971                 /* include a NULL character at the end */
1972                 strbuf_add(&sb, str, strlen(str) + 1);
1973                 free(str);
1974         }
1975         ph->env.numa_nodes = strbuf_detach(&sb, NULL);
1976         return 0;
1977
1978 error:
1979         strbuf_release(&sb);
1980         return -1;
1981 }
1982
1983 static int process_pmu_mappings(struct perf_file_section *section __maybe_unused,
1984                                 struct perf_header *ph, int fd,
1985                                 void *data __maybe_unused)
1986 {
1987         size_t ret;
1988         char *name;
1989         u32 pmu_num;
1990         u32 type;
1991         struct strbuf sb;
1992
1993         ret = readn(fd, &pmu_num, sizeof(pmu_num));
1994         if (ret != sizeof(pmu_num))
1995                 return -1;
1996
1997         if (ph->needs_swap)
1998                 pmu_num = bswap_32(pmu_num);
1999
2000         if (!pmu_num) {
2001                 pr_debug("pmu mappings not available\n");
2002                 return 0;
2003         }
2004
2005         ph->env.nr_pmu_mappings = pmu_num;
2006         strbuf_init(&sb, 128);
2007
2008         while (pmu_num) {
2009                 if (readn(fd, &type, sizeof(type)) != sizeof(type))
2010                         goto error;
2011                 if (ph->needs_swap)
2012                         type = bswap_32(type);
2013
2014                 name = do_read_string(fd, ph);
2015                 if (!name)
2016                         goto error;
2017
2018                 strbuf_addf(&sb, "%u:%s", type, name);
2019                 /* include a NULL character at the end */
2020                 strbuf_add(&sb, "", 1);
2021
2022                 free(name);
2023                 pmu_num--;
2024         }
2025         ph->env.pmu_mappings = strbuf_detach(&sb, NULL);
2026         return 0;
2027
2028 error:
2029         strbuf_release(&sb);
2030         return -1;
2031 }
2032
2033 static int process_group_desc(struct perf_file_section *section __maybe_unused,
2034                               struct perf_header *ph, int fd,
2035                               void *data __maybe_unused)
2036 {
2037         size_t ret = -1;
2038         u32 i, nr, nr_groups;
2039         struct perf_session *session;
2040         struct perf_evsel *evsel, *leader = NULL;
2041         struct group_desc {
2042                 char *name;
2043                 u32 leader_idx;
2044                 u32 nr_members;
2045         } *desc;
2046
2047         if (readn(fd, &nr_groups, sizeof(nr_groups)) != sizeof(nr_groups))
2048                 return -1;
2049
2050         if (ph->needs_swap)
2051                 nr_groups = bswap_32(nr_groups);
2052
2053         ph->env.nr_groups = nr_groups;
2054         if (!nr_groups) {
2055                 pr_debug("group desc not available\n");
2056                 return 0;
2057         }
2058
2059         desc = calloc(nr_groups, sizeof(*desc));
2060         if (!desc)
2061                 return -1;
2062
2063         for (i = 0; i < nr_groups; i++) {
2064                 desc[i].name = do_read_string(fd, ph);
2065                 if (!desc[i].name)
2066                         goto out_free;
2067
2068                 if (readn(fd, &desc[i].leader_idx, sizeof(u32)) != sizeof(u32))
2069                         goto out_free;
2070
2071                 if (readn(fd, &desc[i].nr_members, sizeof(u32)) != sizeof(u32))
2072                         goto out_free;
2073
2074                 if (ph->needs_swap) {
2075                         desc[i].leader_idx = bswap_32(desc[i].leader_idx);
2076                         desc[i].nr_members = bswap_32(desc[i].nr_members);
2077                 }
2078         }
2079
2080         /*
2081          * Rebuild group relationship based on the group_desc
2082          */
2083         session = container_of(ph, struct perf_session, header);
2084         session->evlist->nr_groups = nr_groups;
2085
2086         i = nr = 0;
2087         list_for_each_entry(evsel, &session->evlist->entries, node) {
2088                 if (evsel->idx == (int) desc[i].leader_idx) {
2089                         evsel->leader = evsel;
2090                         /* {anon_group} is a dummy name */
2091                         if (strcmp(desc[i].name, "{anon_group}"))
2092                                 evsel->group_name = desc[i].name;
2093                         evsel->nr_members = desc[i].nr_members;
2094
2095                         if (i >= nr_groups || nr > 0) {
2096                                 pr_debug("invalid group desc\n");
2097                                 goto out_free;
2098                         }
2099
2100                         leader = evsel;
2101                         nr = evsel->nr_members - 1;
2102                         i++;
2103                 } else if (nr) {
2104                         /* This is a group member */
2105                         evsel->leader = leader;
2106
2107                         nr--;
2108                 }
2109         }
2110
2111         if (i != nr_groups || nr != 0) {
2112                 pr_debug("invalid group desc\n");
2113                 goto out_free;
2114         }
2115
2116         ret = 0;
2117 out_free:
2118         while ((int) --i >= 0)
2119                 free(desc[i].name);
2120         free(desc);
2121
2122         return ret;
2123 }
2124
2125 struct feature_ops {
2126         int (*write)(int fd, struct perf_header *h, struct perf_evlist *evlist);
2127         void (*print)(struct perf_header *h, int fd, FILE *fp);
2128         int (*process)(struct perf_file_section *section,
2129                        struct perf_header *h, int fd, void *data);
2130         const char *name;
2131         bool full_only;
2132 };
2133
2134 #define FEAT_OPA(n, func) \
2135         [n] = { .name = #n, .write = write_##func, .print = print_##func }
2136 #define FEAT_OPP(n, func) \
2137         [n] = { .name = #n, .write = write_##func, .print = print_##func, \
2138                 .process = process_##func }
2139 #define FEAT_OPF(n, func) \
2140         [n] = { .name = #n, .write = write_##func, .print = print_##func, \
2141                 .process = process_##func, .full_only = true }
2142
2143 /* feature_ops not implemented: */
2144 #define print_tracing_data      NULL
2145 #define print_build_id          NULL
2146
2147 static const struct feature_ops feat_ops[HEADER_LAST_FEATURE] = {
2148         FEAT_OPP(HEADER_TRACING_DATA,   tracing_data),
2149         FEAT_OPP(HEADER_BUILD_ID,       build_id),
2150         FEAT_OPP(HEADER_HOSTNAME,       hostname),
2151         FEAT_OPP(HEADER_OSRELEASE,      osrelease),
2152         FEAT_OPP(HEADER_VERSION,        version),
2153         FEAT_OPP(HEADER_ARCH,           arch),
2154         FEAT_OPP(HEADER_NRCPUS,         nrcpus),
2155         FEAT_OPP(HEADER_CPUDESC,        cpudesc),
2156         FEAT_OPP(HEADER_CPUID,          cpuid),
2157         FEAT_OPP(HEADER_TOTAL_MEM,      total_mem),
2158         FEAT_OPP(HEADER_EVENT_DESC,     event_desc),
2159         FEAT_OPP(HEADER_CMDLINE,        cmdline),
2160         FEAT_OPF(HEADER_CPU_TOPOLOGY,   cpu_topology),
2161         FEAT_OPF(HEADER_NUMA_TOPOLOGY,  numa_topology),
2162         FEAT_OPA(HEADER_BRANCH_STACK,   branch_stack),
2163         FEAT_OPP(HEADER_PMU_MAPPINGS,   pmu_mappings),
2164         FEAT_OPP(HEADER_GROUP_DESC,     group_desc),
2165 };
2166
2167 struct header_print_data {
2168         FILE *fp;
2169         bool full; /* extended list of headers */
2170 };
2171
2172 static int perf_file_section__fprintf_info(struct perf_file_section *section,
2173                                            struct perf_header *ph,
2174                                            int feat, int fd, void *data)
2175 {
2176         struct header_print_data *hd = data;
2177
2178         if (lseek(fd, section->offset, SEEK_SET) == (off_t)-1) {
2179                 pr_debug("Failed to lseek to %" PRIu64 " offset for feature "
2180                                 "%d, continuing...\n", section->offset, feat);
2181                 return 0;
2182         }
2183         if (feat >= HEADER_LAST_FEATURE) {
2184                 pr_warning("unknown feature %d\n", feat);
2185                 return 0;
2186         }
2187         if (!feat_ops[feat].print)
2188                 return 0;
2189
2190         if (!feat_ops[feat].full_only || hd->full)
2191                 feat_ops[feat].print(ph, fd, hd->fp);
2192         else
2193                 fprintf(hd->fp, "# %s info available, use -I to display\n",
2194                         feat_ops[feat].name);
2195
2196         return 0;
2197 }
2198
2199 int perf_header__fprintf_info(struct perf_session *session, FILE *fp, bool full)
2200 {
2201         struct header_print_data hd;
2202         struct perf_header *header = &session->header;
2203         int fd = session->fd;
2204         hd.fp = fp;
2205         hd.full = full;
2206
2207         perf_header__process_sections(header, fd, &hd,
2208                                       perf_file_section__fprintf_info);
2209         return 0;
2210 }
2211
2212 static int do_write_feat(int fd, struct perf_header *h, int type,
2213                          struct perf_file_section **p,
2214                          struct perf_evlist *evlist)
2215 {
2216         int err;
2217         int ret = 0;
2218
2219         if (perf_header__has_feat(h, type)) {
2220                 if (!feat_ops[type].write)
2221                         return -1;
2222
2223                 (*p)->offset = lseek(fd, 0, SEEK_CUR);
2224
2225                 err = feat_ops[type].write(fd, h, evlist);
2226                 if (err < 0) {
2227                         pr_debug("failed to write feature %d\n", type);
2228
2229                         /* undo anything written */
2230                         lseek(fd, (*p)->offset, SEEK_SET);
2231
2232                         return -1;
2233                 }
2234                 (*p)->size = lseek(fd, 0, SEEK_CUR) - (*p)->offset;
2235                 (*p)++;
2236         }
2237         return ret;
2238 }
2239
2240 static int perf_header__adds_write(struct perf_header *header,
2241                                    struct perf_evlist *evlist, int fd)
2242 {
2243         int nr_sections;
2244         struct perf_file_section *feat_sec, *p;
2245         int sec_size;
2246         u64 sec_start;
2247         int feat;
2248         int err;
2249
2250         nr_sections = bitmap_weight(header->adds_features, HEADER_FEAT_BITS);
2251         if (!nr_sections)
2252                 return 0;
2253
2254         feat_sec = p = calloc(nr_sections, sizeof(*feat_sec));
2255         if (feat_sec == NULL)
2256                 return -ENOMEM;
2257
2258         sec_size = sizeof(*feat_sec) * nr_sections;
2259
2260         sec_start = header->data_offset + header->data_size;
2261         lseek(fd, sec_start + sec_size, SEEK_SET);
2262
2263         for_each_set_bit(feat, header->adds_features, HEADER_FEAT_BITS) {
2264                 if (do_write_feat(fd, header, feat, &p, evlist))
2265                         perf_header__clear_feat(header, feat);
2266         }
2267
2268         lseek(fd, sec_start, SEEK_SET);
2269         /*
2270          * may write more than needed due to dropped feature, but
2271          * this is okay, reader will skip the mising entries
2272          */
2273         err = do_write(fd, feat_sec, sec_size);
2274         if (err < 0)
2275                 pr_debug("failed to write feature section\n");
2276         free(feat_sec);
2277         return err;
2278 }
2279
2280 int perf_header__write_pipe(int fd)
2281 {
2282         struct perf_pipe_file_header f_header;
2283         int err;
2284
2285         f_header = (struct perf_pipe_file_header){
2286                 .magic     = PERF_MAGIC,
2287                 .size      = sizeof(f_header),
2288         };
2289
2290         err = do_write(fd, &f_header, sizeof(f_header));
2291         if (err < 0) {
2292                 pr_debug("failed to write perf pipe header\n");
2293                 return err;
2294         }
2295
2296         return 0;
2297 }
2298
2299 int perf_session__write_header(struct perf_session *session,
2300                                struct perf_evlist *evlist,
2301                                int fd, bool at_exit)
2302 {
2303         struct perf_file_header f_header;
2304         struct perf_file_attr   f_attr;
2305         struct perf_header *header = &session->header;
2306         struct perf_evsel *evsel, *pair = NULL;
2307         int err;
2308
2309         lseek(fd, sizeof(f_header), SEEK_SET);
2310
2311         if (session->evlist != evlist)
2312                 pair = perf_evlist__first(session->evlist);
2313
2314         list_for_each_entry(evsel, &evlist->entries, node) {
2315                 evsel->id_offset = lseek(fd, 0, SEEK_CUR);
2316                 err = do_write(fd, evsel->id, evsel->ids * sizeof(u64));
2317                 if (err < 0) {
2318 out_err_write:
2319                         pr_debug("failed to write perf header\n");
2320                         return err;
2321                 }
2322                 if (session->evlist != evlist) {
2323                         err = do_write(fd, pair->id, pair->ids * sizeof(u64));
2324                         if (err < 0)
2325                                 goto out_err_write;
2326                         evsel->ids += pair->ids;
2327                         pair = perf_evsel__next(pair);
2328                 }
2329         }
2330
2331         header->attr_offset = lseek(fd, 0, SEEK_CUR);
2332
2333         list_for_each_entry(evsel, &evlist->entries, node) {
2334                 f_attr = (struct perf_file_attr){
2335                         .attr = evsel->attr,
2336                         .ids  = {
2337                                 .offset = evsel->id_offset,
2338                                 .size   = evsel->ids * sizeof(u64),
2339                         }
2340                 };
2341                 err = do_write(fd, &f_attr, sizeof(f_attr));
2342                 if (err < 0) {
2343                         pr_debug("failed to write perf header attribute\n");
2344                         return err;
2345                 }
2346         }
2347
2348         header->event_offset = lseek(fd, 0, SEEK_CUR);
2349         header->event_size = trace_event_count * sizeof(struct perf_trace_event_type);
2350         if (trace_events) {
2351                 err = do_write(fd, trace_events, header->event_size);
2352                 if (err < 0) {
2353                         pr_debug("failed to write perf header events\n");
2354                         return err;
2355                 }
2356         }
2357
2358         header->data_offset = lseek(fd, 0, SEEK_CUR);
2359
2360         if (at_exit) {
2361                 err = perf_header__adds_write(header, evlist, fd);
2362                 if (err < 0)
2363                         return err;
2364         }
2365
2366         f_header = (struct perf_file_header){
2367                 .magic     = PERF_MAGIC,
2368                 .size      = sizeof(f_header),
2369                 .attr_size = sizeof(f_attr),
2370                 .attrs = {
2371                         .offset = header->attr_offset,
2372                         .size   = evlist->nr_entries * sizeof(f_attr),
2373                 },
2374                 .data = {
2375                         .offset = header->data_offset,
2376                         .size   = header->data_size,
2377                 },
2378                 .event_types = {
2379                         .offset = header->event_offset,
2380                         .size   = header->event_size,
2381                 },
2382         };
2383
2384         memcpy(&f_header.adds_features, &header->adds_features, sizeof(header->adds_features));
2385
2386         lseek(fd, 0, SEEK_SET);
2387         err = do_write(fd, &f_header, sizeof(f_header));
2388         if (err < 0) {
2389                 pr_debug("failed to write perf header\n");
2390                 return err;
2391         }
2392         lseek(fd, header->data_offset + header->data_size, SEEK_SET);
2393
2394         header->frozen = 1;
2395         return 0;
2396 }
2397
2398 static int perf_header__getbuffer64(struct perf_header *header,
2399                                     int fd, void *buf, size_t size)
2400 {
2401         if (readn(fd, buf, size) <= 0)
2402                 return -1;
2403
2404         if (header->needs_swap)
2405                 mem_bswap_64(buf, size);
2406
2407         return 0;
2408 }
2409
2410 int perf_header__process_sections(struct perf_header *header, int fd,
2411                                   void *data,
2412                                   int (*process)(struct perf_file_section *section,
2413                                                  struct perf_header *ph,
2414                                                  int feat, int fd, void *data))
2415 {
2416         struct perf_file_section *feat_sec, *sec;
2417         int nr_sections;
2418         int sec_size;
2419         int feat;
2420         int err;
2421
2422         nr_sections = bitmap_weight(header->adds_features, HEADER_FEAT_BITS);
2423         if (!nr_sections)
2424                 return 0;
2425
2426         feat_sec = sec = calloc(nr_sections, sizeof(*feat_sec));
2427         if (!feat_sec)
2428                 return -1;
2429
2430         sec_size = sizeof(*feat_sec) * nr_sections;
2431
2432         lseek(fd, header->data_offset + header->data_size, SEEK_SET);
2433
2434         err = perf_header__getbuffer64(header, fd, feat_sec, sec_size);
2435         if (err < 0)
2436                 goto out_free;
2437
2438         for_each_set_bit(feat, header->adds_features, HEADER_LAST_FEATURE) {
2439                 err = process(sec++, header, feat, fd, data);
2440                 if (err < 0)
2441                         goto out_free;
2442         }
2443         err = 0;
2444 out_free:
2445         free(feat_sec);
2446         return err;
2447 }
2448
2449 static const int attr_file_abi_sizes[] = {
2450         [0] = PERF_ATTR_SIZE_VER0,
2451         [1] = PERF_ATTR_SIZE_VER1,
2452         [2] = PERF_ATTR_SIZE_VER2,
2453         [3] = PERF_ATTR_SIZE_VER3,
2454         0,
2455 };
2456
2457 /*
2458  * In the legacy file format, the magic number is not used to encode endianness.
2459  * hdr_sz was used to encode endianness. But given that hdr_sz can vary based
2460  * on ABI revisions, we need to try all combinations for all endianness to
2461  * detect the endianness.
2462  */
2463 static int try_all_file_abis(uint64_t hdr_sz, struct perf_header *ph)
2464 {
2465         uint64_t ref_size, attr_size;
2466         int i;
2467
2468         for (i = 0 ; attr_file_abi_sizes[i]; i++) {
2469                 ref_size = attr_file_abi_sizes[i]
2470                          + sizeof(struct perf_file_section);
2471                 if (hdr_sz != ref_size) {
2472                         attr_size = bswap_64(hdr_sz);
2473                         if (attr_size != ref_size)
2474                                 continue;
2475
2476                         ph->needs_swap = true;
2477                 }
2478                 pr_debug("ABI%d perf.data file detected, need_swap=%d\n",
2479                          i,
2480                          ph->needs_swap);
2481                 return 0;
2482         }
2483         /* could not determine endianness */
2484         return -1;
2485 }
2486
2487 #define PERF_PIPE_HDR_VER0      16
2488
2489 static const size_t attr_pipe_abi_sizes[] = {
2490         [0] = PERF_PIPE_HDR_VER0,
2491         0,
2492 };
2493
2494 /*
2495  * In the legacy pipe format, there is an implicit assumption that endiannesss
2496  * between host recording the samples, and host parsing the samples is the
2497  * same. This is not always the case given that the pipe output may always be
2498  * redirected into a file and analyzed on a different machine with possibly a
2499  * different endianness and perf_event ABI revsions in the perf tool itself.
2500  */
2501 static int try_all_pipe_abis(uint64_t hdr_sz, struct perf_header *ph)
2502 {
2503         u64 attr_size;
2504         int i;
2505
2506         for (i = 0 ; attr_pipe_abi_sizes[i]; i++) {
2507                 if (hdr_sz != attr_pipe_abi_sizes[i]) {
2508                         attr_size = bswap_64(hdr_sz);
2509                         if (attr_size != hdr_sz)
2510                                 continue;
2511
2512                         ph->needs_swap = true;
2513                 }
2514                 pr_debug("Pipe ABI%d perf.data file detected\n", i);
2515                 return 0;
2516         }
2517         return -1;
2518 }
2519
2520 bool is_perf_magic(u64 magic)
2521 {
2522         if (!memcmp(&magic, __perf_magic1, sizeof(magic))
2523                 || magic == __perf_magic2
2524                 || magic == __perf_magic2_sw)
2525                 return true;
2526
2527         return false;
2528 }
2529
2530 static int check_magic_endian(u64 magic, uint64_t hdr_sz,
2531                               bool is_pipe, struct perf_header *ph)
2532 {
2533         int ret;
2534
2535         /* check for legacy format */
2536         ret = memcmp(&magic, __perf_magic1, sizeof(magic));
2537         if (ret == 0) {
2538                 pr_debug("legacy perf.data format\n");
2539                 if (is_pipe)
2540                         return try_all_pipe_abis(hdr_sz, ph);
2541
2542                 return try_all_file_abis(hdr_sz, ph);
2543         }
2544         /*
2545          * the new magic number serves two purposes:
2546          * - unique number to identify actual perf.data files
2547          * - encode endianness of file
2548          */
2549
2550         /* check magic number with one endianness */
2551         if (magic == __perf_magic2)
2552                 return 0;
2553
2554         /* check magic number with opposite endianness */
2555         if (magic != __perf_magic2_sw)
2556                 return -1;
2557
2558         ph->needs_swap = true;
2559
2560         return 0;
2561 }
2562
2563 int perf_file_header__read(struct perf_file_header *header,
2564                            struct perf_header *ph, int fd)
2565 {
2566         int ret;
2567
2568         lseek(fd, 0, SEEK_SET);
2569
2570         ret = readn(fd, header, sizeof(*header));
2571         if (ret <= 0)
2572                 return -1;
2573
2574         if (check_magic_endian(header->magic,
2575                                header->attr_size, false, ph) < 0) {
2576                 pr_debug("magic/endian check failed\n");
2577                 return -1;
2578         }
2579
2580         if (ph->needs_swap) {
2581                 mem_bswap_64(header, offsetof(struct perf_file_header,
2582                              adds_features));
2583         }
2584
2585         if (header->size != sizeof(*header)) {
2586                 /* Support the previous format */
2587                 if (header->size == offsetof(typeof(*header), adds_features))
2588                         bitmap_zero(header->adds_features, HEADER_FEAT_BITS);
2589                 else
2590                         return -1;
2591         } else if (ph->needs_swap) {
2592                 /*
2593                  * feature bitmap is declared as an array of unsigned longs --
2594                  * not good since its size can differ between the host that
2595                  * generated the data file and the host analyzing the file.
2596                  *
2597                  * We need to handle endianness, but we don't know the size of
2598                  * the unsigned long where the file was generated. Take a best
2599                  * guess at determining it: try 64-bit swap first (ie., file
2600                  * created on a 64-bit host), and check if the hostname feature
2601                  * bit is set (this feature bit is forced on as of fbe96f2).
2602                  * If the bit is not, undo the 64-bit swap and try a 32-bit
2603                  * swap. If the hostname bit is still not set (e.g., older data
2604                  * file), punt and fallback to the original behavior --
2605                  * clearing all feature bits and setting buildid.
2606                  */
2607                 mem_bswap_64(&header->adds_features,
2608                             BITS_TO_U64(HEADER_FEAT_BITS));
2609
2610                 if (!test_bit(HEADER_HOSTNAME, header->adds_features)) {
2611                         /* unswap as u64 */
2612                         mem_bswap_64(&header->adds_features,
2613                                     BITS_TO_U64(HEADER_FEAT_BITS));
2614
2615                         /* unswap as u32 */
2616                         mem_bswap_32(&header->adds_features,
2617                                     BITS_TO_U32(HEADER_FEAT_BITS));
2618                 }
2619
2620                 if (!test_bit(HEADER_HOSTNAME, header->adds_features)) {
2621                         bitmap_zero(header->adds_features, HEADER_FEAT_BITS);
2622                         set_bit(HEADER_BUILD_ID, header->adds_features);
2623                 }
2624         }
2625
2626         memcpy(&ph->adds_features, &header->adds_features,
2627                sizeof(ph->adds_features));
2628
2629         ph->event_offset = header->event_types.offset;
2630         ph->event_size   = header->event_types.size;
2631         ph->data_offset  = header->data.offset;
2632         ph->data_size    = header->data.size;
2633         return 0;
2634 }
2635
2636 static int perf_file_section__process(struct perf_file_section *section,
2637                                       struct perf_header *ph,
2638                                       int feat, int fd, void *data)
2639 {
2640         if (lseek(fd, section->offset, SEEK_SET) == (off_t)-1) {
2641                 pr_debug("Failed to lseek to %" PRIu64 " offset for feature "
2642                           "%d, continuing...\n", section->offset, feat);
2643                 return 0;
2644         }
2645
2646         if (feat >= HEADER_LAST_FEATURE) {
2647                 pr_debug("unknown feature %d, continuing...\n", feat);
2648                 return 0;
2649         }
2650
2651         if (!feat_ops[feat].process)
2652                 return 0;
2653
2654         return feat_ops[feat].process(section, ph, fd, data);
2655 }
2656
2657 static int perf_file_header__read_pipe(struct perf_pipe_file_header *header,
2658                                        struct perf_header *ph, int fd,
2659                                        bool repipe)
2660 {
2661         int ret;
2662
2663         ret = readn(fd, header, sizeof(*header));
2664         if (ret <= 0)
2665                 return -1;
2666
2667         if (check_magic_endian(header->magic, header->size, true, ph) < 0) {
2668                 pr_debug("endian/magic failed\n");
2669                 return -1;
2670         }
2671
2672         if (ph->needs_swap)
2673                 header->size = bswap_64(header->size);
2674
2675         if (repipe && do_write(STDOUT_FILENO, header, sizeof(*header)) < 0)
2676                 return -1;
2677
2678         return 0;
2679 }
2680
2681 static int perf_header__read_pipe(struct perf_session *session, int fd)
2682 {
2683         struct perf_header *header = &session->header;
2684         struct perf_pipe_file_header f_header;
2685
2686         if (perf_file_header__read_pipe(&f_header, header, fd,
2687                                         session->repipe) < 0) {
2688                 pr_debug("incompatible file format\n");
2689                 return -EINVAL;
2690         }
2691
2692         session->fd = fd;
2693
2694         return 0;
2695 }
2696
2697 static int read_attr(int fd, struct perf_header *ph,
2698                      struct perf_file_attr *f_attr)
2699 {
2700         struct perf_event_attr *attr = &f_attr->attr;
2701         size_t sz, left;
2702         size_t our_sz = sizeof(f_attr->attr);
2703         int ret;
2704
2705         memset(f_attr, 0, sizeof(*f_attr));
2706
2707         /* read minimal guaranteed structure */
2708         ret = readn(fd, attr, PERF_ATTR_SIZE_VER0);
2709         if (ret <= 0) {
2710                 pr_debug("cannot read %d bytes of header attr\n",
2711                          PERF_ATTR_SIZE_VER0);
2712                 return -1;
2713         }
2714
2715         /* on file perf_event_attr size */
2716         sz = attr->size;
2717
2718         if (ph->needs_swap)
2719                 sz = bswap_32(sz);
2720
2721         if (sz == 0) {
2722                 /* assume ABI0 */
2723                 sz =  PERF_ATTR_SIZE_VER0;
2724         } else if (sz > our_sz) {
2725                 pr_debug("file uses a more recent and unsupported ABI"
2726                          " (%zu bytes extra)\n", sz - our_sz);
2727                 return -1;
2728         }
2729         /* what we have not yet read and that we know about */
2730         left = sz - PERF_ATTR_SIZE_VER0;
2731         if (left) {
2732                 void *ptr = attr;
2733                 ptr += PERF_ATTR_SIZE_VER0;
2734
2735                 ret = readn(fd, ptr, left);
2736         }
2737         /* read perf_file_section, ids are read in caller */
2738         ret = readn(fd, &f_attr->ids, sizeof(f_attr->ids));
2739
2740         return ret <= 0 ? -1 : 0;
2741 }
2742
2743 static int perf_evsel__prepare_tracepoint_event(struct perf_evsel *evsel,
2744                                                 struct pevent *pevent)
2745 {
2746         struct event_format *event;
2747         char bf[128];
2748
2749         /* already prepared */
2750         if (evsel->tp_format)
2751                 return 0;
2752
2753         if (pevent == NULL) {
2754                 pr_debug("broken or missing trace data\n");
2755                 return -1;
2756         }
2757
2758         event = pevent_find_event(pevent, evsel->attr.config);
2759         if (event == NULL)
2760                 return -1;
2761
2762         if (!evsel->name) {
2763                 snprintf(bf, sizeof(bf), "%s:%s", event->system, event->name);
2764                 evsel->name = strdup(bf);
2765                 if (evsel->name == NULL)
2766                         return -1;
2767         }
2768
2769         evsel->tp_format = event;
2770         return 0;
2771 }
2772
2773 static int perf_evlist__prepare_tracepoint_events(struct perf_evlist *evlist,
2774                                                   struct pevent *pevent)
2775 {
2776         struct perf_evsel *pos;
2777
2778         list_for_each_entry(pos, &evlist->entries, node) {
2779                 if (pos->attr.type == PERF_TYPE_TRACEPOINT &&
2780                     perf_evsel__prepare_tracepoint_event(pos, pevent))
2781                         return -1;
2782         }
2783
2784         return 0;
2785 }
2786
2787 int perf_session__read_header(struct perf_session *session, int fd)
2788 {
2789         struct perf_header *header = &session->header;
2790         struct perf_file_header f_header;
2791         struct perf_file_attr   f_attr;
2792         u64                     f_id;
2793         int nr_attrs, nr_ids, i, j;
2794
2795         session->evlist = perf_evlist__new();
2796         if (session->evlist == NULL)
2797                 return -ENOMEM;
2798
2799         if (session->fd_pipe)
2800                 return perf_header__read_pipe(session, fd);
2801
2802         if (perf_file_header__read(&f_header, header, fd) < 0)
2803                 return -EINVAL;
2804
2805         nr_attrs = f_header.attrs.size / f_header.attr_size;
2806         lseek(fd, f_header.attrs.offset, SEEK_SET);
2807
2808         for (i = 0; i < nr_attrs; i++) {
2809                 struct perf_evsel *evsel;
2810                 off_t tmp;
2811
2812                 if (read_attr(fd, header, &f_attr) < 0)
2813                         goto out_errno;
2814
2815                 if (header->needs_swap)
2816                         perf_event__attr_swap(&f_attr.attr);
2817
2818                 tmp = lseek(fd, 0, SEEK_CUR);
2819                 evsel = perf_evsel__new(&f_attr.attr, i);
2820
2821                 if (evsel == NULL)
2822                         goto out_delete_evlist;
2823
2824                 evsel->needs_swap = header->needs_swap;
2825                 /*
2826                  * Do it before so that if perf_evsel__alloc_id fails, this
2827                  * entry gets purged too at perf_evlist__delete().
2828                  */
2829                 perf_evlist__add(session->evlist, evsel);
2830
2831                 nr_ids = f_attr.ids.size / sizeof(u64);
2832                 /*
2833                  * We don't have the cpu and thread maps on the header, so
2834                  * for allocating the perf_sample_id table we fake 1 cpu and
2835                  * hattr->ids threads.
2836                  */
2837                 if (perf_evsel__alloc_id(evsel, 1, nr_ids))
2838                         goto out_delete_evlist;
2839
2840                 lseek(fd, f_attr.ids.offset, SEEK_SET);
2841
2842                 for (j = 0; j < nr_ids; j++) {
2843                         if (perf_header__getbuffer64(header, fd, &f_id, sizeof(f_id)))
2844                                 goto out_errno;
2845
2846                         perf_evlist__id_add(session->evlist, evsel, 0, j, f_id);
2847                 }
2848
2849                 lseek(fd, tmp, SEEK_SET);
2850         }
2851
2852         symbol_conf.nr_events = nr_attrs;
2853
2854         if (f_header.event_types.size) {
2855                 lseek(fd, f_header.event_types.offset, SEEK_SET);
2856                 trace_events = malloc(f_header.event_types.size);
2857                 if (trace_events == NULL)
2858                         return -ENOMEM;
2859                 if (perf_header__getbuffer64(header, fd, trace_events,
2860                                              f_header.event_types.size))
2861                         goto out_errno;
2862                 trace_event_count =  f_header.event_types.size / sizeof(struct perf_trace_event_type);
2863         }
2864
2865         perf_header__process_sections(header, fd, &session->pevent,
2866                                       perf_file_section__process);
2867
2868         lseek(fd, header->data_offset, SEEK_SET);
2869
2870         if (perf_evlist__prepare_tracepoint_events(session->evlist,
2871                                                    session->pevent))
2872                 goto out_delete_evlist;
2873
2874         header->frozen = 1;
2875         return 0;
2876 out_errno:
2877         return -errno;
2878
2879 out_delete_evlist:
2880         perf_evlist__delete(session->evlist);
2881         session->evlist = NULL;
2882         return -ENOMEM;
2883 }
2884
2885 int perf_event__synthesize_attr(struct perf_tool *tool,
2886                                 struct perf_event_attr *attr, u32 ids, u64 *id,
2887                                 perf_event__handler_t process)
2888 {
2889         union perf_event *ev;
2890         size_t size;
2891         int err;
2892
2893         size = sizeof(struct perf_event_attr);
2894         size = PERF_ALIGN(size, sizeof(u64));
2895         size += sizeof(struct perf_event_header);
2896         size += ids * sizeof(u64);
2897
2898         ev = malloc(size);
2899
2900         if (ev == NULL)
2901                 return -ENOMEM;
2902
2903         ev->attr.attr = *attr;
2904         memcpy(ev->attr.id, id, ids * sizeof(u64));
2905
2906         ev->attr.header.type = PERF_RECORD_HEADER_ATTR;
2907         ev->attr.header.size = (u16)size;
2908
2909         if (ev->attr.header.size == size)
2910                 err = process(tool, ev, NULL, NULL);
2911         else
2912                 err = -E2BIG;
2913
2914         free(ev);
2915
2916         return err;
2917 }
2918
2919 int perf_event__synthesize_attrs(struct perf_tool *tool,
2920                                    struct perf_session *session,
2921                                    perf_event__handler_t process)
2922 {
2923         struct perf_evsel *evsel;
2924         int err = 0;
2925
2926         list_for_each_entry(evsel, &session->evlist->entries, node) {
2927                 err = perf_event__synthesize_attr(tool, &evsel->attr, evsel->ids,
2928                                                   evsel->id, process);
2929                 if (err) {
2930                         pr_debug("failed to create perf header attribute\n");
2931                         return err;
2932                 }
2933         }
2934
2935         return err;
2936 }
2937
2938 int perf_event__process_attr(union perf_event *event,
2939                              struct perf_evlist **pevlist)
2940 {
2941         u32 i, ids, n_ids;
2942         struct perf_evsel *evsel;
2943         struct perf_evlist *evlist = *pevlist;
2944
2945         if (evlist == NULL) {
2946                 *pevlist = evlist = perf_evlist__new();
2947                 if (evlist == NULL)
2948                         return -ENOMEM;
2949         }
2950
2951         evsel = perf_evsel__new(&event->attr.attr, evlist->nr_entries);
2952         if (evsel == NULL)
2953                 return -ENOMEM;
2954
2955         perf_evlist__add(evlist, evsel);
2956
2957         ids = event->header.size;
2958         ids -= (void *)&event->attr.id - (void *)event;
2959         n_ids = ids / sizeof(u64);
2960         /*
2961          * We don't have the cpu and thread maps on the header, so
2962          * for allocating the perf_sample_id table we fake 1 cpu and
2963          * hattr->ids threads.
2964          */
2965         if (perf_evsel__alloc_id(evsel, 1, n_ids))
2966                 return -ENOMEM;
2967
2968         for (i = 0; i < n_ids; i++) {
2969                 perf_evlist__id_add(evlist, evsel, 0, i, event->attr.id[i]);
2970         }
2971
2972         return 0;
2973 }
2974
2975 int perf_event__synthesize_event_type(struct perf_tool *tool,
2976                                       u64 event_id, char *name,
2977                                       perf_event__handler_t process,
2978                                       struct machine *machine)
2979 {
2980         union perf_event ev;
2981         size_t size = 0;
2982         int err = 0;
2983
2984         memset(&ev, 0, sizeof(ev));
2985
2986         ev.event_type.event_type.event_id = event_id;
2987         memset(ev.event_type.event_type.name, 0, MAX_EVENT_NAME);
2988         strncpy(ev.event_type.event_type.name, name, MAX_EVENT_NAME - 1);
2989
2990         ev.event_type.header.type = PERF_RECORD_HEADER_EVENT_TYPE;
2991         size = strlen(ev.event_type.event_type.name);
2992         size = PERF_ALIGN(size, sizeof(u64));
2993         ev.event_type.header.size = sizeof(ev.event_type) -
2994                 (sizeof(ev.event_type.event_type.name) - size);
2995
2996         err = process(tool, &ev, NULL, machine);
2997
2998         return err;
2999 }
3000
3001 int perf_event__synthesize_event_types(struct perf_tool *tool,
3002                                        perf_event__handler_t process,
3003                                        struct machine *machine)
3004 {
3005         struct perf_trace_event_type *type;
3006         int i, err = 0;
3007
3008         for (i = 0; i < trace_event_count; i++) {
3009                 type = &trace_events[i];
3010
3011                 err = perf_event__synthesize_event_type(tool, type->event_id,
3012                                                         type->name, process,
3013                                                         machine);
3014                 if (err) {
3015                         pr_debug("failed to create perf header event type\n");
3016                         return err;
3017                 }
3018         }
3019
3020         return err;
3021 }
3022
3023 int perf_event__process_event_type(struct perf_tool *tool __maybe_unused,
3024                                    union perf_event *event)
3025 {
3026         if (perf_header__push_event(event->event_type.event_type.event_id,
3027                                     event->event_type.event_type.name) < 0)
3028                 return -ENOMEM;
3029
3030         return 0;
3031 }
3032
3033 int perf_event__synthesize_tracing_data(struct perf_tool *tool, int fd,
3034                                         struct perf_evlist *evlist,
3035                                         perf_event__handler_t process)
3036 {
3037         union perf_event ev;
3038         struct tracing_data *tdata;
3039         ssize_t size = 0, aligned_size = 0, padding;
3040         int err __maybe_unused = 0;
3041
3042         /*
3043          * We are going to store the size of the data followed
3044          * by the data contents. Since the fd descriptor is a pipe,
3045          * we cannot seek back to store the size of the data once
3046          * we know it. Instead we:
3047          *
3048          * - write the tracing data to the temp file
3049          * - get/write the data size to pipe
3050          * - write the tracing data from the temp file
3051          *   to the pipe
3052          */
3053         tdata = tracing_data_get(&evlist->entries, fd, true);
3054         if (!tdata)
3055                 return -1;
3056
3057         memset(&ev, 0, sizeof(ev));
3058
3059         ev.tracing_data.header.type = PERF_RECORD_HEADER_TRACING_DATA;
3060         size = tdata->size;
3061         aligned_size = PERF_ALIGN(size, sizeof(u64));
3062         padding = aligned_size - size;
3063         ev.tracing_data.header.size = sizeof(ev.tracing_data);
3064         ev.tracing_data.size = aligned_size;
3065
3066         process(tool, &ev, NULL, NULL);
3067
3068         /*
3069          * The put function will copy all the tracing data
3070          * stored in temp file to the pipe.
3071          */
3072         tracing_data_put(tdata);
3073
3074         write_padded(fd, NULL, 0, padding);
3075
3076         return aligned_size;
3077 }
3078
3079 int perf_event__process_tracing_data(union perf_event *event,
3080                                      struct perf_session *session)
3081 {
3082         ssize_t size_read, padding, size = event->tracing_data.size;
3083         off_t offset = lseek(session->fd, 0, SEEK_CUR);
3084         char buf[BUFSIZ];
3085
3086         /* setup for reading amidst mmap */
3087         lseek(session->fd, offset + sizeof(struct tracing_data_event),
3088               SEEK_SET);
3089
3090         size_read = trace_report(session->fd, &session->pevent,
3091                                  session->repipe);
3092         padding = PERF_ALIGN(size_read, sizeof(u64)) - size_read;
3093
3094         if (readn(session->fd, buf, padding) < 0) {
3095                 pr_err("%s: reading input file", __func__);
3096                 return -1;
3097         }
3098         if (session->repipe) {
3099                 int retw = write(STDOUT_FILENO, buf, padding);
3100                 if (retw <= 0 || retw != padding) {
3101                         pr_err("%s: repiping tracing data padding", __func__);
3102                         return -1;
3103                 }
3104         }
3105
3106         if (size_read + padding != size) {
3107                 pr_err("%s: tracing data size mismatch", __func__);
3108                 return -1;
3109         }
3110
3111         perf_evlist__prepare_tracepoint_events(session->evlist,
3112                                                session->pevent);
3113
3114         return size_read + padding;
3115 }
3116
3117 int perf_event__synthesize_build_id(struct perf_tool *tool,
3118                                     struct dso *pos, u16 misc,
3119                                     perf_event__handler_t process,
3120                                     struct machine *machine)
3121 {
3122         union perf_event ev;
3123         size_t len;
3124         int err = 0;
3125
3126         if (!pos->hit)
3127                 return err;
3128
3129         memset(&ev, 0, sizeof(ev));
3130
3131         len = pos->long_name_len + 1;
3132         len = PERF_ALIGN(len, NAME_ALIGN);
3133         memcpy(&ev.build_id.build_id, pos->build_id, sizeof(pos->build_id));
3134         ev.build_id.header.type = PERF_RECORD_HEADER_BUILD_ID;
3135         ev.build_id.header.misc = misc;
3136         ev.build_id.pid = machine->pid;
3137         ev.build_id.header.size = sizeof(ev.build_id) + len;
3138         memcpy(&ev.build_id.filename, pos->long_name, pos->long_name_len);
3139
3140         err = process(tool, &ev, NULL, machine);
3141
3142         return err;
3143 }
3144
3145 int perf_event__process_build_id(struct perf_tool *tool __maybe_unused,
3146                                  union perf_event *event,
3147                                  struct perf_session *session)
3148 {
3149         __event_process_build_id(&event->build_id,
3150                                  event->build_id.filename,
3151                                  session);
3152         return 0;
3153 }
3154
3155 void disable_buildid_cache(void)
3156 {
3157         no_buildid_cache = true;
3158 }