1 // SPDX-License-Identifier: GPL-2.0
7 * Copyright (C) 2009, 2010 Red Hat Inc.
8 * Copyright (C) 2009, 2010 Arnaldo Carvalho de Melo <acme@redhat.com>
10 #include "util.h" // lsdir(), mkdir_p(), rm_rf()
15 #include <sys/types.h>
16 #include "util/copyfile.h"
20 #include "namespaces.h"
24 #include <linux/kernel.h>
31 #include "probe-file.h"
34 #ifdef HAVE_DEBUGINFOD_SUPPORT
35 #include <elfutils/debuginfod.h>
38 #include <linux/ctype.h>
39 #include <linux/zalloc.h>
42 static bool no_buildid_cache;
44 int build_id__mark_dso_hit(struct perf_tool *tool __maybe_unused,
45 union perf_event *event,
46 struct perf_sample *sample,
47 struct evsel *evsel __maybe_unused,
48 struct machine *machine)
50 struct addr_location al;
51 struct thread *thread = machine__findnew_thread(machine, sample->pid,
55 pr_err("problem processing %d event, skipping it.\n",
60 if (thread__find_map(thread, sample->cpumode, sample->ip, &al))
67 static int perf_event__exit_del_thread(struct perf_tool *tool __maybe_unused,
68 union perf_event *event,
69 struct perf_sample *sample
71 struct machine *machine)
73 struct thread *thread = machine__findnew_thread(machine,
77 dump_printf("(%d:%d):(%d:%d)\n", event->fork.pid, event->fork.tid,
78 event->fork.ppid, event->fork.ptid);
81 machine__remove_thread(machine, thread);
88 struct perf_tool build_id__mark_dso_hit_ops = {
89 .sample = build_id__mark_dso_hit,
90 .mmap = perf_event__process_mmap,
91 .mmap2 = perf_event__process_mmap2,
92 .fork = perf_event__process_fork,
93 .exit = perf_event__exit_del_thread,
94 .attr = perf_event__process_attr,
95 .build_id = perf_event__process_build_id,
96 .ordered_events = true,
99 int build_id__sprintf(const struct build_id *build_id, char *bf)
102 const u8 *raw = build_id->data;
107 for (i = 0; i < build_id->size; ++i) {
108 sprintf(bid, "%02x", *raw);
113 return (bid - bf) + 1;
116 int sysfs__sprintf_build_id(const char *root_dir, char *sbuild_id)
118 char notes[PATH_MAX];
125 scnprintf(notes, sizeof(notes), "%s/sys/kernel/notes", root_dir);
127 ret = sysfs__read_build_id(notes, &bid);
131 return build_id__sprintf(&bid, sbuild_id);
134 int filename__sprintf_build_id(const char *pathname, char *sbuild_id)
139 ret = filename__read_build_id(pathname, &bid);
143 return build_id__sprintf(&bid, sbuild_id);
146 /* asnprintf consolidates asprintf and snprintf */
147 static int asnprintf(char **strp, size_t size, const char *fmt, ...)
157 ret = vsnprintf(*strp, size, fmt, ap);
159 ret = vasprintf(strp, fmt, ap);
165 char *build_id_cache__kallsyms_path(const char *sbuild_id, char *bf,
168 bool retry_old = true;
170 snprintf(bf, size, "%s/%s/%s/kallsyms",
171 buildid_dir, DSO__NAME_KALLSYMS, sbuild_id);
173 if (!access(bf, F_OK))
176 /* Try old style kallsyms cache */
177 snprintf(bf, size, "%s/%s/%s",
178 buildid_dir, DSO__NAME_KALLSYMS, sbuild_id);
186 char *build_id_cache__linkname(const char *sbuild_id, char *bf, size_t size)
189 int ret = asnprintf(&bf, size, "%s/.build-id/%.2s/%s", buildid_dir,
190 sbuild_id, sbuild_id + 2);
191 if (ret < 0 || (tmp && size < (unsigned int)ret))
196 /* The caller is responsible to free the returned buffer. */
197 char *build_id_cache__origname(const char *sbuild_id)
201 char *ret = NULL, *p;
202 size_t offs = 5; /* == strlen("../..") */
205 linkname = build_id_cache__linkname(sbuild_id, NULL, 0);
209 len = readlink(linkname, buf, sizeof(buf) - 1);
214 /* The link should be "../..<origpath>/<sbuild_id>" */
215 p = strrchr(buf, '/'); /* Cut off the "/<sbuild_id>" */
216 if (p && (p > buf + offs)) {
218 if (buf[offs + 1] == '[')
220 * This is a DSO name, like [kernel.kallsyms].
221 * Skip the first '/', since this is not the
222 * cache of a regular file.
224 ret = strdup(buf + offs); /* Skip "../..[/]" */
231 /* Check if the given build_id cache is valid on current running system */
232 static bool build_id_cache__valid_id(char *sbuild_id)
234 char real_sbuild_id[SBUILD_ID_SIZE] = "";
239 pathname = build_id_cache__origname(sbuild_id);
243 if (!strcmp(pathname, DSO__NAME_KALLSYMS))
244 ret = sysfs__sprintf_build_id("/", real_sbuild_id);
245 else if (pathname[0] == '/')
246 ret = filename__sprintf_build_id(pathname, real_sbuild_id);
248 ret = -EINVAL; /* Should we support other special DSO cache? */
250 result = (strcmp(sbuild_id, real_sbuild_id) == 0);
256 static const char *build_id_cache__basename(bool is_kallsyms, bool is_vdso,
259 return is_kallsyms ? "kallsyms" : (is_vdso ? "vdso" : (is_debug ?
263 char *dso__build_id_filename(const struct dso *dso, char *bf, size_t size,
266 bool is_kallsyms = dso__is_kallsyms((struct dso *)dso);
267 bool is_vdso = dso__is_vdso((struct dso *)dso);
268 char sbuild_id[SBUILD_ID_SIZE];
270 bool alloc = (bf == NULL);
273 if (!dso->has_build_id)
276 build_id__sprintf(&dso->bid, sbuild_id);
277 linkname = build_id_cache__linkname(sbuild_id, NULL, 0);
281 /* Check if old style build_id cache */
282 if (is_regular_file(linkname))
283 ret = asnprintf(&bf, size, "%s", linkname);
285 ret = asnprintf(&bf, size, "%s/%s", linkname,
286 build_id_cache__basename(is_kallsyms, is_vdso,
288 if (ret < 0 || (!alloc && size < (unsigned int)ret))
295 #define dsos__for_each_with_build_id(pos, head) \
296 list_for_each_entry(pos, head, node) \
297 if (!pos->has_build_id) \
301 static int write_buildid(const char *name, size_t name_len, struct build_id *bid,
302 pid_t pid, u16 misc, struct feat_fd *fd)
305 struct perf_record_header_build_id b;
309 len = PERF_ALIGN(len, NAME_ALIGN);
311 memset(&b, 0, sizeof(b));
312 memcpy(&b.data, bid->data, bid->size);
313 b.size = (u8) bid->size;
314 misc |= PERF_RECORD_MISC_BUILD_ID_SIZE;
316 b.header.misc = misc;
317 b.header.size = sizeof(b) + len;
319 err = do_write(fd, &b, sizeof(b));
323 return write_padded(fd, name, name_len + 1, len);
326 static int machine__write_buildid_table(struct machine *machine,
331 u16 kmisc = PERF_RECORD_MISC_KERNEL,
332 umisc = PERF_RECORD_MISC_USER;
334 if (!machine__is_host(machine)) {
335 kmisc = PERF_RECORD_MISC_GUEST_KERNEL;
336 umisc = PERF_RECORD_MISC_GUEST_USER;
339 dsos__for_each_with_build_id(pos, &machine->dsos.head) {
342 bool in_kernel = false;
344 if (!pos->hit && !dso__is_vdso(pos))
347 if (dso__is_vdso(pos)) {
348 name = pos->short_name;
349 name_len = pos->short_name_len;
350 } else if (dso__is_kcore(pos)) {
351 name = machine->mmap_name;
352 name_len = strlen(name);
354 name = pos->long_name;
355 name_len = pos->long_name_len;
358 in_kernel = pos->kernel ||
359 is_kernel_module(name,
360 PERF_RECORD_MISC_CPUMODE_UNKNOWN);
361 err = write_buildid(name, name_len, &pos->bid, machine->pid,
362 in_kernel ? kmisc : umisc, fd);
370 int perf_session__write_buildid_table(struct perf_session *session,
374 int err = machine__write_buildid_table(&session->machines.host, fd);
379 for (nd = rb_first_cached(&session->machines.guests); nd;
381 struct machine *pos = rb_entry(nd, struct machine, rb_node);
382 err = machine__write_buildid_table(pos, fd);
389 static int __dsos__hit_all(struct list_head *head)
393 list_for_each_entry(pos, head, node)
399 static int machine__hit_all_dsos(struct machine *machine)
401 return __dsos__hit_all(&machine->dsos.head);
404 int dsos__hit_all(struct perf_session *session)
409 err = machine__hit_all_dsos(&session->machines.host);
413 for (nd = rb_first_cached(&session->machines.guests); nd;
415 struct machine *pos = rb_entry(nd, struct machine, rb_node);
417 err = machine__hit_all_dsos(pos);
425 void disable_buildid_cache(void)
427 no_buildid_cache = true;
430 static bool lsdir_bid_head_filter(const char *name __maybe_unused,
433 return (strlen(d->d_name) == 2) &&
434 isxdigit(d->d_name[0]) && isxdigit(d->d_name[1]);
437 static bool lsdir_bid_tail_filter(const char *name __maybe_unused,
441 while (isxdigit(d->d_name[i]) && i < SBUILD_ID_SIZE - 3)
443 return (i == SBUILD_ID_SIZE - 3) && (d->d_name[i] == '\0');
446 struct strlist *build_id_cache__list_all(bool validonly)
448 struct strlist *toplist, *linklist = NULL, *bidlist;
449 struct str_node *nd, *nd2;
450 char *topdir, *linkdir = NULL;
451 char sbuild_id[SBUILD_ID_SIZE];
453 /* for filename__ functions */
457 /* Open the top-level directory */
458 if (asprintf(&topdir, "%s/.build-id/", buildid_dir) < 0)
461 bidlist = strlist__new(NULL, NULL);
465 toplist = lsdir(topdir, lsdir_bid_head_filter);
467 pr_debug("Error in lsdir(%s): %d\n", topdir, errno);
468 /* If there is no buildid cache, return an empty list */
474 strlist__for_each_entry(nd, toplist) {
475 if (asprintf(&linkdir, "%s/%s", topdir, nd->s) < 0)
477 /* Open the lower-level directory */
478 linklist = lsdir(linkdir, lsdir_bid_tail_filter);
480 pr_debug("Error in lsdir(%s): %d\n", linkdir, errno);
483 strlist__for_each_entry(nd2, linklist) {
484 if (snprintf(sbuild_id, SBUILD_ID_SIZE, "%s%s",
485 nd->s, nd2->s) != SBUILD_ID_SIZE - 1)
487 if (validonly && !build_id_cache__valid_id(sbuild_id))
489 if (strlist__add(bidlist, sbuild_id) < 0)
492 strlist__delete(linklist);
497 strlist__delete(toplist);
504 strlist__delete(linklist);
506 strlist__delete(bidlist);
511 static bool str_is_build_id(const char *maybe_sbuild_id, size_t len)
515 for (i = 0; i < len; i++) {
516 if (!isxdigit(maybe_sbuild_id[i]))
522 /* Return the valid complete build-id */
523 char *build_id_cache__complement(const char *incomplete_sbuild_id)
525 struct strlist *bidlist;
526 struct str_node *nd, *cand = NULL;
527 char *sbuild_id = NULL;
528 size_t len = strlen(incomplete_sbuild_id);
530 if (len >= SBUILD_ID_SIZE ||
531 !str_is_build_id(incomplete_sbuild_id, len))
534 bidlist = build_id_cache__list_all(true);
538 strlist__for_each_entry(nd, bidlist) {
539 if (strncmp(nd->s, incomplete_sbuild_id, len) != 0)
541 if (cand) { /* Error: There are more than 2 candidates. */
548 sbuild_id = strdup(cand->s);
549 strlist__delete(bidlist);
554 char *build_id_cache__cachedir(const char *sbuild_id, const char *name,
555 struct nsinfo *nsi, bool is_kallsyms,
558 char *realname = (char *)name, *filename;
559 bool slash = is_kallsyms || is_vdso;
562 realname = nsinfo__realpath(name, nsi);
567 if (asprintf(&filename, "%s%s%s%s%s", buildid_dir, slash ? "/" : "",
568 is_vdso ? DSO__NAME_VDSO : realname,
569 sbuild_id ? "/" : "", sbuild_id ?: "") < 0)
578 int build_id_cache__list_build_ids(const char *pathname, struct nsinfo *nsi,
579 struct strlist **result)
584 dir_name = build_id_cache__cachedir(NULL, pathname, nsi, false, false);
588 *result = lsdir(dir_name, lsdir_no_dot_filter);
596 #if defined(HAVE_LIBELF_SUPPORT) && defined(HAVE_GELF_GETNOTE_SUPPORT)
597 static int build_id_cache__add_sdt_cache(const char *sbuild_id,
598 const char *realname,
601 struct probe_cache *cache;
605 cache = probe_cache__new(sbuild_id, nsi);
609 nsinfo__mountns_enter(nsi, &nsc);
610 ret = probe_cache__scan_sdt(cache, realname);
611 nsinfo__mountns_exit(&nsc);
613 pr_debug4("Found %d SDTs in %s\n", ret, realname);
614 if (probe_cache__commit(cache) < 0)
617 probe_cache__delete(cache);
621 #define build_id_cache__add_sdt_cache(sbuild_id, realname, nsi) (0)
624 static char *build_id_cache__find_debug(const char *sbuild_id,
627 char *realname = NULL;
632 debugfile = calloc(1, PATH_MAX);
636 len = __symbol__join_symfs(debugfile, PATH_MAX,
637 "/usr/lib/debug/.build-id/");
638 snprintf(debugfile + len, PATH_MAX - len, "%.2s/%s.debug", sbuild_id,
641 nsinfo__mountns_enter(nsi, &nsc);
642 realname = realpath(debugfile, NULL);
643 if (realname && access(realname, R_OK))
645 nsinfo__mountns_exit(&nsc);
647 #ifdef HAVE_DEBUGINFOD_SUPPORT
648 if (realname == NULL) {
649 debuginfod_client* c = debuginfod_begin();
651 int fd = debuginfod_find_debuginfo(c,
652 (const unsigned char*)sbuild_id, 0,
655 close(fd); /* retaining reference by realname */
666 int build_id_cache__add_s(const char *sbuild_id, const char *name,
667 struct nsinfo *nsi, bool is_kallsyms, bool is_vdso)
669 const size_t size = PATH_MAX;
670 char *realname = NULL, *filename = NULL, *dir_name = NULL,
671 *linkname = zalloc(size), *tmp;
672 char *debugfile = NULL;
677 realname = nsinfo__realpath(name, nsi);
679 realname = realpath(name, NULL);
684 dir_name = build_id_cache__cachedir(sbuild_id, name, nsi, is_kallsyms,
689 /* Remove old style build-id cache */
690 if (is_regular_file(dir_name))
691 if (unlink(dir_name))
694 if (mkdir_p(dir_name, 0755))
697 /* Save the allocated buildid dirname */
698 if (asprintf(&filename, "%s/%s", dir_name,
699 build_id_cache__basename(is_kallsyms, is_vdso,
705 if (access(filename, F_OK)) {
707 if (copyfile("/proc/kallsyms", filename))
709 } else if (nsi && nsi->need_setns) {
710 if (copyfile_ns(name, filename, nsi))
712 } else if (link(realname, filename) && errno != EEXIST &&
713 copyfile(name, filename))
717 /* Some binaries are stripped, but have .debug files with their symbol
718 * table. Check to see if we can locate one of those, since the elf
719 * file itself may not be very useful to users of our tools without a
722 if (!is_kallsyms && !is_vdso &&
723 strncmp(".ko", name + strlen(name) - 3, 3)) {
724 debugfile = build_id_cache__find_debug(sbuild_id, nsi);
727 if (asprintf(&filename, "%s/%s", dir_name,
728 build_id_cache__basename(false, false, true)) < 0) {
732 if (access(filename, F_OK)) {
733 if (nsi && nsi->need_setns) {
734 if (copyfile_ns(debugfile, filename,
737 } else if (link(debugfile, filename) &&
739 copyfile(debugfile, filename))
745 if (!build_id_cache__linkname(sbuild_id, linkname, size))
747 tmp = strrchr(linkname, '/');
750 if (access(linkname, X_OK) && mkdir_p(linkname, 0755))
754 tmp = dir_name + strlen(buildid_dir) - 5;
755 memcpy(tmp, "../..", 5);
757 if (symlink(tmp, linkname) == 0)
760 /* Update SDT cache : error is just warned */
762 build_id_cache__add_sdt_cache(sbuild_id, realname, nsi) < 0)
763 pr_debug4("Failed to update/scan SDT cache for %s\n", realname);
775 static int build_id_cache__add_b(const struct build_id *bid,
776 const char *name, struct nsinfo *nsi,
777 bool is_kallsyms, bool is_vdso)
779 char sbuild_id[SBUILD_ID_SIZE];
781 build_id__sprintf(bid, sbuild_id);
783 return build_id_cache__add_s(sbuild_id, name, nsi, is_kallsyms,
787 bool build_id_cache__cached(const char *sbuild_id)
790 char *filename = build_id_cache__linkname(sbuild_id, NULL, 0);
792 if (filename && !access(filename, F_OK))
799 int build_id_cache__remove_s(const char *sbuild_id)
801 const size_t size = PATH_MAX;
802 char *filename = zalloc(size),
803 *linkname = zalloc(size), *tmp;
806 if (filename == NULL || linkname == NULL)
809 if (!build_id_cache__linkname(sbuild_id, linkname, size))
812 if (access(linkname, F_OK))
815 if (readlink(linkname, filename, size - 1) < 0)
818 if (unlink(linkname))
822 * Since the link is relative, we must make it absolute:
824 tmp = strrchr(linkname, '/') + 1;
825 snprintf(tmp, size - (tmp - linkname), "%s", filename);
837 static int dso__cache_build_id(struct dso *dso, struct machine *machine)
839 bool is_kallsyms = dso__is_kallsyms(dso);
840 bool is_vdso = dso__is_vdso(dso);
841 const char *name = dso->long_name;
843 if (dso__is_kcore(dso)) {
845 name = machine->mmap_name;
847 return build_id_cache__add_b(&dso->bid, name, dso->nsinfo,
848 is_kallsyms, is_vdso);
851 static int __dsos__cache_build_ids(struct list_head *head,
852 struct machine *machine)
857 dsos__for_each_with_build_id(pos, head)
858 if (dso__cache_build_id(pos, machine))
864 static int machine__cache_build_ids(struct machine *machine)
866 return __dsos__cache_build_ids(&machine->dsos.head, machine);
869 int perf_session__cache_build_ids(struct perf_session *session)
874 if (no_buildid_cache)
877 if (mkdir(buildid_dir, 0755) != 0 && errno != EEXIST)
880 ret = machine__cache_build_ids(&session->machines.host);
882 for (nd = rb_first_cached(&session->machines.guests); nd;
884 struct machine *pos = rb_entry(nd, struct machine, rb_node);
885 ret |= machine__cache_build_ids(pos);
890 static bool machine__read_build_ids(struct machine *machine, bool with_hits)
892 return __dsos__read_build_ids(&machine->dsos.head, with_hits);
895 bool perf_session__read_build_ids(struct perf_session *session, bool with_hits)
898 bool ret = machine__read_build_ids(&session->machines.host, with_hits);
900 for (nd = rb_first_cached(&session->machines.guests); nd;
902 struct machine *pos = rb_entry(nd, struct machine, rb_node);
903 ret |= machine__read_build_ids(pos, with_hits);
909 void build_id__init(struct build_id *bid, const u8 *data, size_t size)
911 WARN_ON(size > BUILD_ID_SIZE);
912 memcpy(bid->data, data, size);