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1/*
2 * build-id.c
3 *
4 * build-id support
5 *
6 * Copyright (C) 2009, 2010 Red Hat Inc.
7 * Copyright (C) 2009, 2010 Arnaldo Carvalho de Melo <acme@redhat.com>
8 */
9#include "util.h"
10#include <stdio.h>
11#include "build-id.h"
12#include "event.h"
13#include "symbol.h"
14#include <linux/kernel.h>
15#include "debug.h"
16#include "session.h"
17#include "tool.h"
18#include "header.h"
19#include "vdso.h"
20
21
22static bool no_buildid_cache;
23
24int build_id__mark_dso_hit(struct perf_tool *tool __maybe_unused,
25 union perf_event *event,
26 struct perf_sample *sample,
27 struct perf_evsel *evsel __maybe_unused,
28 struct machine *machine)
29{
30 struct addr_location al;
31 struct thread *thread = machine__findnew_thread(machine, sample->pid,
32 sample->tid);
33
34 if (thread == NULL) {
35 pr_err("problem processing %d event, skipping it.\n",
36 event->header.type);
37 return -1;
38 }
39
40 thread__find_addr_map(thread, sample->cpumode, MAP__FUNCTION, sample->ip, &al);
41
42 if (al.map != NULL)
43 al.map->dso->hit = 1;
44
45 thread__put(thread);
46 return 0;
47}
48
49static int perf_event__exit_del_thread(struct perf_tool *tool __maybe_unused,
50 union perf_event *event,
51 struct perf_sample *sample
52 __maybe_unused,
53 struct machine *machine)
54{
55 struct thread *thread = machine__findnew_thread(machine,
56 event->fork.pid,
57 event->fork.tid);
58
59 dump_printf("(%d:%d):(%d:%d)\n", event->fork.pid, event->fork.tid,
60 event->fork.ppid, event->fork.ptid);
61
62 if (thread) {
63 machine__remove_thread(machine, thread);
64 thread__put(thread);
65 }
66
67 return 0;
68}
69
70struct perf_tool build_id__mark_dso_hit_ops = {
71 .sample = build_id__mark_dso_hit,
72 .mmap = perf_event__process_mmap,
73 .mmap2 = perf_event__process_mmap2,
74 .fork = perf_event__process_fork,
75 .exit = perf_event__exit_del_thread,
76 .attr = perf_event__process_attr,
77 .build_id = perf_event__process_build_id,
78 .ordered_events = true,
79};
80
81int build_id__sprintf(const u8 *build_id, int len, char *bf)
82{
83 char *bid = bf;
84 const u8 *raw = build_id;
85 int i;
86
87 for (i = 0; i < len; ++i) {
88 sprintf(bid, "%02x", *raw);
89 ++raw;
90 bid += 2;
91 }
92
93 return (bid - bf) + 1;
94}
95
96int sysfs__sprintf_build_id(const char *root_dir, char *sbuild_id)
97{
98 char notes[PATH_MAX];
99 u8 build_id[BUILD_ID_SIZE];
100 int ret;
101
102 if (!root_dir)
103 root_dir = "";
104
105 scnprintf(notes, sizeof(notes), "%s/sys/kernel/notes", root_dir);
106
107 ret = sysfs__read_build_id(notes, build_id, sizeof(build_id));
108 if (ret < 0)
109 return ret;
110
111 return build_id__sprintf(build_id, sizeof(build_id), sbuild_id);
112}
113
114int filename__sprintf_build_id(const char *pathname, char *sbuild_id)
115{
116 u8 build_id[BUILD_ID_SIZE];
117 int ret;
118
119 ret = filename__read_build_id(pathname, build_id, sizeof(build_id));
120 if (ret < 0)
121 return ret;
122 else if (ret != sizeof(build_id))
123 return -EINVAL;
124
125 return build_id__sprintf(build_id, sizeof(build_id), sbuild_id);
126}
127
128/* asnprintf consolidates asprintf and snprintf */
129static int asnprintf(char **strp, size_t size, const char *fmt, ...)
130{
131 va_list ap;
132 int ret;
133
134 if (!strp)
135 return -EINVAL;
136
137 va_start(ap, fmt);
138 if (*strp)
139 ret = vsnprintf(*strp, size, fmt, ap);
140 else
141 ret = vasprintf(strp, fmt, ap);
142 va_end(ap);
143
144 return ret;
145}
146
147static char *build_id__filename(const char *sbuild_id, char *bf, size_t size)
148{
149 char *tmp = bf;
150 int ret = asnprintf(&bf, size, "%s/.build-id/%.2s/%s", buildid_dir,
151 sbuild_id, sbuild_id + 2);
152 if (ret < 0 || (tmp && size < (unsigned int)ret))
153 return NULL;
154 return bf;
155}
156
157char *dso__build_id_filename(const struct dso *dso, char *bf, size_t size)
158{
159 char build_id_hex[SBUILD_ID_SIZE];
160
161 if (!dso->has_build_id)
162 return NULL;
163
164 build_id__sprintf(dso->build_id, sizeof(dso->build_id), build_id_hex);
165 return build_id__filename(build_id_hex, bf, size);
166}
167
168bool dso__build_id_is_kmod(const struct dso *dso, char *bf, size_t size)
169{
170 char *id_name, *ch;
171 struct stat sb;
172
173 id_name = dso__build_id_filename(dso, bf, size);
174 if (!id_name)
175 goto err;
176 if (access(id_name, F_OK))
177 goto err;
178 if (lstat(id_name, &sb) == -1)
179 goto err;
180 if ((size_t)sb.st_size > size - 1)
181 goto err;
182 if (readlink(id_name, bf, size - 1) < 0)
183 goto err;
184
185 bf[sb.st_size] = '\0';
186
187 /*
188 * link should be:
189 * ../../lib/modules/4.4.0-rc4/kernel/net/ipv4/netfilter/nf_nat_ipv4.ko/a09fe3eb3147dafa4e3b31dbd6257e4d696bdc92
190 */
191 ch = strrchr(bf, '/');
192 if (!ch)
193 goto err;
194 if (ch - 3 < bf)
195 goto err;
196
197 return strncmp(".ko", ch - 3, 3) == 0;
198err:
199 /*
200 * If dso__build_id_filename work, get id_name again,
201 * because id_name points to bf and is broken.
202 */
203 if (id_name)
204 id_name = dso__build_id_filename(dso, bf, size);
205 pr_err("Invalid build id: %s\n", id_name ? :
206 dso->long_name ? :
207 dso->short_name ? :
208 "[unknown]");
209 return false;
210}
211
212#define dsos__for_each_with_build_id(pos, head) \
213 list_for_each_entry(pos, head, node) \
214 if (!pos->has_build_id) \
215 continue; \
216 else
217
218static int write_buildid(const char *name, size_t name_len, u8 *build_id,
219 pid_t pid, u16 misc, int fd)
220{
221 int err;
222 struct build_id_event b;
223 size_t len;
224
225 len = name_len + 1;
226 len = PERF_ALIGN(len, NAME_ALIGN);
227
228 memset(&b, 0, sizeof(b));
229 memcpy(&b.build_id, build_id, BUILD_ID_SIZE);
230 b.pid = pid;
231 b.header.misc = misc;
232 b.header.size = sizeof(b) + len;
233
234 err = writen(fd, &b, sizeof(b));
235 if (err < 0)
236 return err;
237
238 return write_padded(fd, name, name_len + 1, len);
239}
240
241static int machine__write_buildid_table(struct machine *machine, int fd)
242{
243 int err = 0;
244 char nm[PATH_MAX];
245 struct dso *pos;
246 u16 kmisc = PERF_RECORD_MISC_KERNEL,
247 umisc = PERF_RECORD_MISC_USER;
248
249 if (!machine__is_host(machine)) {
250 kmisc = PERF_RECORD_MISC_GUEST_KERNEL;
251 umisc = PERF_RECORD_MISC_GUEST_USER;
252 }
253
254 dsos__for_each_with_build_id(pos, &machine->dsos.head) {
255 const char *name;
256 size_t name_len;
257 bool in_kernel = false;
258
259 if (!pos->hit)
260 continue;
261
262 if (dso__is_vdso(pos)) {
263 name = pos->short_name;
264 name_len = pos->short_name_len + 1;
265 } else if (dso__is_kcore(pos)) {
266 machine__mmap_name(machine, nm, sizeof(nm));
267 name = nm;
268 name_len = strlen(nm) + 1;
269 } else {
270 name = pos->long_name;
271 name_len = pos->long_name_len + 1;
272 }
273
274 in_kernel = pos->kernel ||
275 is_kernel_module(name,
276 PERF_RECORD_MISC_CPUMODE_UNKNOWN);
277 err = write_buildid(name, name_len, pos->build_id, machine->pid,
278 in_kernel ? kmisc : umisc, fd);
279 if (err)
280 break;
281 }
282
283 return err;
284}
285
286int perf_session__write_buildid_table(struct perf_session *session, int fd)
287{
288 struct rb_node *nd;
289 int err = machine__write_buildid_table(&session->machines.host, fd);
290
291 if (err)
292 return err;
293
294 for (nd = rb_first(&session->machines.guests); nd; nd = rb_next(nd)) {
295 struct machine *pos = rb_entry(nd, struct machine, rb_node);
296 err = machine__write_buildid_table(pos, fd);
297 if (err)
298 break;
299 }
300 return err;
301}
302
303static int __dsos__hit_all(struct list_head *head)
304{
305 struct dso *pos;
306
307 list_for_each_entry(pos, head, node)
308 pos->hit = true;
309
310 return 0;
311}
312
313static int machine__hit_all_dsos(struct machine *machine)
314{
315 return __dsos__hit_all(&machine->dsos.head);
316}
317
318int dsos__hit_all(struct perf_session *session)
319{
320 struct rb_node *nd;
321 int err;
322
323 err = machine__hit_all_dsos(&session->machines.host);
324 if (err)
325 return err;
326
327 for (nd = rb_first(&session->machines.guests); nd; nd = rb_next(nd)) {
328 struct machine *pos = rb_entry(nd, struct machine, rb_node);
329
330 err = machine__hit_all_dsos(pos);
331 if (err)
332 return err;
333 }
334
335 return 0;
336}
337
338void disable_buildid_cache(void)
339{
340 no_buildid_cache = true;
341}
342
343static char *build_id_cache__dirname_from_path(const char *name,
344 bool is_kallsyms, bool is_vdso)
345{
346 char *realname = (char *)name, *filename;
347 bool slash = is_kallsyms || is_vdso;
348
349 if (!slash) {
350 realname = realpath(name, NULL);
351 if (!realname)
352 return NULL;
353 }
354
355 if (asprintf(&filename, "%s%s%s", buildid_dir, slash ? "/" : "",
356 is_vdso ? DSO__NAME_VDSO : realname) < 0)
357 filename = NULL;
358
359 if (!slash)
360 free(realname);
361
362 return filename;
363}
364
365int build_id_cache__list_build_ids(const char *pathname,
366 struct strlist **result)
367{
368 struct strlist *list;
369 char *dir_name;
370 DIR *dir;
371 struct dirent *d;
372 int ret = 0;
373
374 list = strlist__new(NULL, NULL);
375 dir_name = build_id_cache__dirname_from_path(pathname, false, false);
376 if (!list || !dir_name) {
377 ret = -ENOMEM;
378 goto out;
379 }
380
381 /* List up all dirents */
382 dir = opendir(dir_name);
383 if (!dir) {
384 ret = -errno;
385 goto out;
386 }
387
388 while ((d = readdir(dir)) != NULL) {
389 if (!strcmp(d->d_name, ".") || !strcmp(d->d_name, ".."))
390 continue;
391 strlist__add(list, d->d_name);
392 }
393 closedir(dir);
394
395out:
396 free(dir_name);
397 if (ret)
398 strlist__delete(list);
399 else
400 *result = list;
401
402 return ret;
403}
404
405int build_id_cache__add_s(const char *sbuild_id, const char *name,
406 bool is_kallsyms, bool is_vdso)
407{
408 const size_t size = PATH_MAX;
409 char *realname = NULL, *filename = NULL, *dir_name = NULL,
410 *linkname = zalloc(size), *targetname, *tmp;
411 int err = -1;
412
413 if (!is_kallsyms) {
414 realname = realpath(name, NULL);
415 if (!realname)
416 goto out_free;
417 }
418
419 dir_name = build_id_cache__dirname_from_path(name, is_kallsyms, is_vdso);
420 if (!dir_name)
421 goto out_free;
422
423 if (mkdir_p(dir_name, 0755))
424 goto out_free;
425
426 if (asprintf(&filename, "%s/%s", dir_name, sbuild_id) < 0) {
427 filename = NULL;
428 goto out_free;
429 }
430
431 if (access(filename, F_OK)) {
432 if (is_kallsyms) {
433 if (copyfile("/proc/kallsyms", filename))
434 goto out_free;
435 } else if (link(realname, filename) && errno != EEXIST &&
436 copyfile(name, filename))
437 goto out_free;
438 }
439
440 if (!build_id__filename(sbuild_id, linkname, size))
441 goto out_free;
442 tmp = strrchr(linkname, '/');
443 *tmp = '\0';
444
445 if (access(linkname, X_OK) && mkdir_p(linkname, 0755))
446 goto out_free;
447
448 *tmp = '/';
449 targetname = filename + strlen(buildid_dir) - 5;
450 memcpy(targetname, "../..", 5);
451
452 if (symlink(targetname, linkname) == 0)
453 err = 0;
454out_free:
455 if (!is_kallsyms)
456 free(realname);
457 free(filename);
458 free(dir_name);
459 free(linkname);
460 return err;
461}
462
463static int build_id_cache__add_b(const u8 *build_id, size_t build_id_size,
464 const char *name, bool is_kallsyms,
465 bool is_vdso)
466{
467 char sbuild_id[SBUILD_ID_SIZE];
468
469 build_id__sprintf(build_id, build_id_size, sbuild_id);
470
471 return build_id_cache__add_s(sbuild_id, name, is_kallsyms, is_vdso);
472}
473
474bool build_id_cache__cached(const char *sbuild_id)
475{
476 bool ret = false;
477 char *filename = build_id__filename(sbuild_id, NULL, 0);
478
479 if (filename && !access(filename, F_OK))
480 ret = true;
481 free(filename);
482
483 return ret;
484}
485
486int build_id_cache__remove_s(const char *sbuild_id)
487{
488 const size_t size = PATH_MAX;
489 char *filename = zalloc(size),
490 *linkname = zalloc(size), *tmp;
491 int err = -1;
492
493 if (filename == NULL || linkname == NULL)
494 goto out_free;
495
496 if (!build_id__filename(sbuild_id, linkname, size))
497 goto out_free;
498
499 if (access(linkname, F_OK))
500 goto out_free;
501
502 if (readlink(linkname, filename, size - 1) < 0)
503 goto out_free;
504
505 if (unlink(linkname))
506 goto out_free;
507
508 /*
509 * Since the link is relative, we must make it absolute:
510 */
511 tmp = strrchr(linkname, '/') + 1;
512 snprintf(tmp, size - (tmp - linkname), "%s", filename);
513
514 if (unlink(linkname))
515 goto out_free;
516
517 err = 0;
518out_free:
519 free(filename);
520 free(linkname);
521 return err;
522}
523
524static int dso__cache_build_id(struct dso *dso, struct machine *machine)
525{
526 bool is_kallsyms = dso->kernel && dso->long_name[0] != '/';
527 bool is_vdso = dso__is_vdso(dso);
528 const char *name = dso->long_name;
529 char nm[PATH_MAX];
530
531 if (dso__is_kcore(dso)) {
532 is_kallsyms = true;
533 machine__mmap_name(machine, nm, sizeof(nm));
534 name = nm;
535 }
536 return build_id_cache__add_b(dso->build_id, sizeof(dso->build_id), name,
537 is_kallsyms, is_vdso);
538}
539
540static int __dsos__cache_build_ids(struct list_head *head,
541 struct machine *machine)
542{
543 struct dso *pos;
544 int err = 0;
545
546 dsos__for_each_with_build_id(pos, head)
547 if (dso__cache_build_id(pos, machine))
548 err = -1;
549
550 return err;
551}
552
553static int machine__cache_build_ids(struct machine *machine)
554{
555 return __dsos__cache_build_ids(&machine->dsos.head, machine);
556}
557
558int perf_session__cache_build_ids(struct perf_session *session)
559{
560 struct rb_node *nd;
561 int ret;
562
563 if (no_buildid_cache)
564 return 0;
565
566 if (mkdir(buildid_dir, 0755) != 0 && errno != EEXIST)
567 return -1;
568
569 ret = machine__cache_build_ids(&session->machines.host);
570
571 for (nd = rb_first(&session->machines.guests); nd; nd = rb_next(nd)) {
572 struct machine *pos = rb_entry(nd, struct machine, rb_node);
573 ret |= machine__cache_build_ids(pos);
574 }
575 return ret ? -1 : 0;
576}
577
578static bool machine__read_build_ids(struct machine *machine, bool with_hits)
579{
580 return __dsos__read_build_ids(&machine->dsos.head, with_hits);
581}
582
583bool perf_session__read_build_ids(struct perf_session *session, bool with_hits)
584{
585 struct rb_node *nd;
586 bool ret = machine__read_build_ids(&session->machines.host, with_hits);
587
588 for (nd = rb_first(&session->machines.guests); nd; nd = rb_next(nd)) {
589 struct machine *pos = rb_entry(nd, struct machine, rb_node);
590 ret |= machine__read_build_ids(pos, with_hits);
591 }
592
593 return ret;
594}
1/*
2 * build-id.c
3 *
4 * build-id support
5 *
6 * Copyright (C) 2009, 2010 Red Hat Inc.
7 * Copyright (C) 2009, 2010 Arnaldo Carvalho de Melo <acme@redhat.com>
8 */
9#include "util.h"
10#include <stdio.h>
11#include "build-id.h"
12#include "event.h"
13#include "symbol.h"
14#include <linux/kernel.h>
15#include "debug.h"
16#include "session.h"
17#include "tool.h"
18
19static int build_id__mark_dso_hit(struct perf_tool *tool __used,
20 union perf_event *event,
21 struct perf_sample *sample __used,
22 struct perf_evsel *evsel __used,
23 struct machine *machine)
24{
25 struct addr_location al;
26 u8 cpumode = event->header.misc & PERF_RECORD_MISC_CPUMODE_MASK;
27 struct thread *thread = machine__findnew_thread(machine, event->ip.pid);
28
29 if (thread == NULL) {
30 pr_err("problem processing %d event, skipping it.\n",
31 event->header.type);
32 return -1;
33 }
34
35 thread__find_addr_map(thread, machine, cpumode, MAP__FUNCTION,
36 event->ip.ip, &al);
37
38 if (al.map != NULL)
39 al.map->dso->hit = 1;
40
41 return 0;
42}
43
44static int perf_event__exit_del_thread(struct perf_tool *tool __used,
45 union perf_event *event,
46 struct perf_sample *sample __used,
47 struct machine *machine)
48{
49 struct thread *thread = machine__findnew_thread(machine, event->fork.tid);
50
51 dump_printf("(%d:%d):(%d:%d)\n", event->fork.pid, event->fork.tid,
52 event->fork.ppid, event->fork.ptid);
53
54 if (thread) {
55 rb_erase(&thread->rb_node, &machine->threads);
56 machine->last_match = NULL;
57 thread__delete(thread);
58 }
59
60 return 0;
61}
62
63struct perf_tool build_id__mark_dso_hit_ops = {
64 .sample = build_id__mark_dso_hit,
65 .mmap = perf_event__process_mmap,
66 .fork = perf_event__process_task,
67 .exit = perf_event__exit_del_thread,
68 .attr = perf_event__process_attr,
69 .build_id = perf_event__process_build_id,
70};
71
72char *dso__build_id_filename(struct dso *self, char *bf, size_t size)
73{
74 char build_id_hex[BUILD_ID_SIZE * 2 + 1];
75
76 if (!self->has_build_id)
77 return NULL;
78
79 build_id__sprintf(self->build_id, sizeof(self->build_id), build_id_hex);
80 if (bf == NULL) {
81 if (asprintf(&bf, "%s/.build-id/%.2s/%s", buildid_dir,
82 build_id_hex, build_id_hex + 2) < 0)
83 return NULL;
84 } else
85 snprintf(bf, size, "%s/.build-id/%.2s/%s", buildid_dir,
86 build_id_hex, build_id_hex + 2);
87 return bf;
88}