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>
40 #include <linux/string.h>
43 static bool no_buildid_cache;
45 int build_id__mark_dso_hit(struct perf_tool *tool __maybe_unused,
46 union perf_event *event,
47 struct perf_sample *sample,
48 struct evsel *evsel __maybe_unused,
49 struct machine *machine)
51 struct addr_location al;
52 struct thread *thread = machine__findnew_thread(machine, sample->pid,
56 pr_err("problem processing %d event, skipping it.\n",
61 addr_location__init(&al);
62 if (thread__find_map(thread, sample->cpumode, sample->ip, &al))
63 map__dso(al.map)->hit = 1;
65 addr_location__exit(&al);
70 static int perf_event__exit_del_thread(struct perf_tool *tool __maybe_unused,
71 union perf_event *event,
72 struct perf_sample *sample
74 struct machine *machine)
76 struct thread *thread = machine__findnew_thread(machine,
80 dump_printf("(%d:%d):(%d:%d)\n", event->fork.pid, event->fork.tid,
81 event->fork.ppid, event->fork.ptid);
84 machine__remove_thread(machine, thread);
91 struct perf_tool build_id__mark_dso_hit_ops = {
92 .sample = build_id__mark_dso_hit,
93 .mmap = perf_event__process_mmap,
94 .mmap2 = perf_event__process_mmap2,
95 .fork = perf_event__process_fork,
96 .exit = perf_event__exit_del_thread,
97 .attr = perf_event__process_attr,
98 .build_id = perf_event__process_build_id,
99 .ordered_events = true,
102 int build_id__sprintf(const struct build_id *build_id, char *bf)
105 const u8 *raw = build_id->data;
110 for (i = 0; i < build_id->size; ++i) {
111 sprintf(bid, "%02x", *raw);
116 return (bid - bf) + 1;
119 int sysfs__sprintf_build_id(const char *root_dir, char *sbuild_id)
121 char notes[PATH_MAX];
128 scnprintf(notes, sizeof(notes), "%s/sys/kernel/notes", root_dir);
130 ret = sysfs__read_build_id(notes, &bid);
134 return build_id__sprintf(&bid, sbuild_id);
137 int filename__sprintf_build_id(const char *pathname, char *sbuild_id)
142 ret = filename__read_build_id(pathname, &bid);
146 return build_id__sprintf(&bid, sbuild_id);
149 /* asnprintf consolidates asprintf and snprintf */
150 static int asnprintf(char **strp, size_t size, const char *fmt, ...)
160 ret = vsnprintf(*strp, size, fmt, ap);
162 ret = vasprintf(strp, fmt, ap);
168 char *build_id_cache__kallsyms_path(const char *sbuild_id, char *bf,
171 bool retry_old = true;
173 snprintf(bf, size, "%s/%s/%s/kallsyms",
174 buildid_dir, DSO__NAME_KALLSYMS, sbuild_id);
176 if (!access(bf, F_OK))
179 /* Try old style kallsyms cache */
180 snprintf(bf, size, "%s/%s/%s",
181 buildid_dir, DSO__NAME_KALLSYMS, sbuild_id);
189 char *build_id_cache__linkname(const char *sbuild_id, char *bf, size_t size)
192 int ret = asnprintf(&bf, size, "%s/.build-id/%.2s/%s", buildid_dir,
193 sbuild_id, sbuild_id + 2);
194 if (ret < 0 || (tmp && size < (unsigned int)ret))
199 /* The caller is responsible to free the returned buffer. */
200 char *build_id_cache__origname(const char *sbuild_id)
204 char *ret = NULL, *p;
205 size_t offs = 5; /* == strlen("../..") */
208 linkname = build_id_cache__linkname(sbuild_id, NULL, 0);
212 len = readlink(linkname, buf, sizeof(buf) - 1);
217 /* The link should be "../..<origpath>/<sbuild_id>" */
218 p = strrchr(buf, '/'); /* Cut off the "/<sbuild_id>" */
219 if (p && (p > buf + offs)) {
221 if (buf[offs + 1] == '[')
223 * This is a DSO name, like [kernel.kallsyms].
224 * Skip the first '/', since this is not the
225 * cache of a regular file.
227 ret = strdup(buf + offs); /* Skip "../..[/]" */
234 /* Check if the given build_id cache is valid on current running system */
235 static bool build_id_cache__valid_id(char *sbuild_id)
237 char real_sbuild_id[SBUILD_ID_SIZE] = "";
242 pathname = build_id_cache__origname(sbuild_id);
246 if (!strcmp(pathname, DSO__NAME_KALLSYMS))
247 ret = sysfs__sprintf_build_id("/", real_sbuild_id);
248 else if (pathname[0] == '/')
249 ret = filename__sprintf_build_id(pathname, real_sbuild_id);
251 ret = -EINVAL; /* Should we support other special DSO cache? */
253 result = (strcmp(sbuild_id, real_sbuild_id) == 0);
259 static const char *build_id_cache__basename(bool is_kallsyms, bool is_vdso,
262 return is_kallsyms ? "kallsyms" : (is_vdso ? "vdso" : (is_debug ?
266 char *__dso__build_id_filename(const struct dso *dso, char *bf, size_t size,
267 bool is_debug, bool is_kallsyms)
269 bool is_vdso = dso__is_vdso((struct dso *)dso);
270 char sbuild_id[SBUILD_ID_SIZE];
272 bool alloc = (bf == NULL);
275 if (!dso->has_build_id)
278 build_id__sprintf(&dso->bid, sbuild_id);
279 linkname = build_id_cache__linkname(sbuild_id, NULL, 0);
283 /* Check if old style build_id cache */
284 if (is_regular_file(linkname))
285 ret = asnprintf(&bf, size, "%s", linkname);
287 ret = asnprintf(&bf, size, "%s/%s", linkname,
288 build_id_cache__basename(is_kallsyms, is_vdso,
290 if (ret < 0 || (!alloc && size < (unsigned int)ret))
297 char *dso__build_id_filename(const struct dso *dso, char *bf, size_t size,
300 bool is_kallsyms = dso__is_kallsyms((struct dso *)dso);
302 return __dso__build_id_filename(dso, bf, size, is_debug, is_kallsyms);
305 static int write_buildid(const char *name, size_t name_len, struct build_id *bid,
306 pid_t pid, u16 misc, struct feat_fd *fd)
309 struct perf_record_header_build_id b;
313 len = PERF_ALIGN(len, NAME_ALIGN);
315 memset(&b, 0, sizeof(b));
316 memcpy(&b.data, bid->data, bid->size);
317 b.size = (u8) bid->size;
318 misc |= PERF_RECORD_MISC_BUILD_ID_SIZE;
320 b.header.misc = misc;
321 b.header.size = sizeof(b) + len;
323 err = do_write(fd, &b, sizeof(b));
327 return write_padded(fd, name, name_len + 1, len);
330 static int machine__write_buildid_table(struct machine *machine,
335 u16 kmisc = PERF_RECORD_MISC_KERNEL,
336 umisc = PERF_RECORD_MISC_USER;
338 if (!machine__is_host(machine)) {
339 kmisc = PERF_RECORD_MISC_GUEST_KERNEL;
340 umisc = PERF_RECORD_MISC_GUEST_USER;
343 dsos__for_each_with_build_id(pos, &machine->dsos.head) {
346 bool in_kernel = false;
348 if (!pos->hit && !dso__is_vdso(pos))
351 if (dso__is_vdso(pos)) {
352 name = pos->short_name;
353 name_len = pos->short_name_len;
354 } else if (dso__is_kcore(pos)) {
355 name = machine->mmap_name;
356 name_len = strlen(name);
358 name = pos->long_name;
359 name_len = pos->long_name_len;
362 in_kernel = pos->kernel ||
363 is_kernel_module(name,
364 PERF_RECORD_MISC_CPUMODE_UNKNOWN);
365 err = write_buildid(name, name_len, &pos->bid, machine->pid,
366 in_kernel ? kmisc : umisc, fd);
374 int perf_session__write_buildid_table(struct perf_session *session,
378 int err = machine__write_buildid_table(&session->machines.host, fd);
383 for (nd = rb_first_cached(&session->machines.guests); nd;
385 struct machine *pos = rb_entry(nd, struct machine, rb_node);
386 err = machine__write_buildid_table(pos, fd);
393 static int __dsos__hit_all(struct list_head *head)
397 list_for_each_entry(pos, head, node)
403 static int machine__hit_all_dsos(struct machine *machine)
405 return __dsos__hit_all(&machine->dsos.head);
408 int dsos__hit_all(struct perf_session *session)
413 err = machine__hit_all_dsos(&session->machines.host);
417 for (nd = rb_first_cached(&session->machines.guests); nd;
419 struct machine *pos = rb_entry(nd, struct machine, rb_node);
421 err = machine__hit_all_dsos(pos);
429 void disable_buildid_cache(void)
431 no_buildid_cache = true;
434 static bool lsdir_bid_head_filter(const char *name __maybe_unused,
437 return (strlen(d->d_name) == 2) &&
438 isxdigit(d->d_name[0]) && isxdigit(d->d_name[1]);
441 static bool lsdir_bid_tail_filter(const char *name __maybe_unused,
445 while (isxdigit(d->d_name[i]) && i < SBUILD_ID_SIZE - 3)
447 return (i >= SBUILD_ID_MIN_SIZE - 3) && (i <= SBUILD_ID_SIZE - 3) &&
448 (d->d_name[i] == '\0');
451 struct strlist *build_id_cache__list_all(bool validonly)
453 struct strlist *toplist, *linklist = NULL, *bidlist;
454 struct str_node *nd, *nd2;
455 char *topdir, *linkdir = NULL;
456 char sbuild_id[SBUILD_ID_SIZE];
458 /* for filename__ functions */
462 /* Open the top-level directory */
463 if (asprintf(&topdir, "%s/.build-id/", buildid_dir) < 0)
466 bidlist = strlist__new(NULL, NULL);
470 toplist = lsdir(topdir, lsdir_bid_head_filter);
472 pr_debug("Error in lsdir(%s): %d\n", topdir, errno);
473 /* If there is no buildid cache, return an empty list */
479 strlist__for_each_entry(nd, toplist) {
480 if (asprintf(&linkdir, "%s/%s", topdir, nd->s) < 0)
482 /* Open the lower-level directory */
483 linklist = lsdir(linkdir, lsdir_bid_tail_filter);
485 pr_debug("Error in lsdir(%s): %d\n", linkdir, errno);
488 strlist__for_each_entry(nd2, linklist) {
489 if (snprintf(sbuild_id, SBUILD_ID_SIZE, "%s%s",
490 nd->s, nd2->s) > SBUILD_ID_SIZE - 1)
492 if (validonly && !build_id_cache__valid_id(sbuild_id))
494 if (strlist__add(bidlist, sbuild_id) < 0)
497 strlist__delete(linklist);
502 strlist__delete(toplist);
509 strlist__delete(linklist);
511 strlist__delete(bidlist);
516 static bool str_is_build_id(const char *maybe_sbuild_id, size_t len)
520 for (i = 0; i < len; i++) {
521 if (!isxdigit(maybe_sbuild_id[i]))
527 /* Return the valid complete build-id */
528 char *build_id_cache__complement(const char *incomplete_sbuild_id)
530 struct strlist *bidlist;
531 struct str_node *nd, *cand = NULL;
532 char *sbuild_id = NULL;
533 size_t len = strlen(incomplete_sbuild_id);
535 if (len >= SBUILD_ID_SIZE ||
536 !str_is_build_id(incomplete_sbuild_id, len))
539 bidlist = build_id_cache__list_all(true);
543 strlist__for_each_entry(nd, bidlist) {
544 if (strncmp(nd->s, incomplete_sbuild_id, len) != 0)
546 if (cand) { /* Error: There are more than 2 candidates. */
553 sbuild_id = strdup(cand->s);
554 strlist__delete(bidlist);
559 char *build_id_cache__cachedir(const char *sbuild_id, const char *name,
560 struct nsinfo *nsi, bool is_kallsyms,
563 char *realname = NULL, *filename;
564 bool slash = is_kallsyms || is_vdso;
567 realname = nsinfo__realpath(name, nsi);
569 if (asprintf(&filename, "%s%s%s%s%s", buildid_dir, slash ? "/" : "",
570 is_vdso ? DSO__NAME_VDSO : (realname ? realname : name),
571 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,
626 const char *root_dir)
628 const char *dirname = "/usr/lib/debug/.build-id/";
629 char *realname = NULL;
630 char dirbuf[PATH_MAX];
635 debugfile = calloc(1, PATH_MAX);
640 path__join(dirbuf, PATH_MAX, root_dir, dirname);
644 len = __symbol__join_symfs(debugfile, PATH_MAX, dirname);
645 snprintf(debugfile + len, PATH_MAX - len, "%.2s/%s.debug", sbuild_id,
648 nsinfo__mountns_enter(nsi, &nsc);
649 realname = realpath(debugfile, NULL);
650 if (realname && access(realname, R_OK))
652 nsinfo__mountns_exit(&nsc);
654 #ifdef HAVE_DEBUGINFOD_SUPPORT
655 if (realname == NULL) {
656 debuginfod_client* c;
658 pr_debug("Downloading debug info with build id %s\n", sbuild_id);
660 c = debuginfod_begin();
662 int fd = debuginfod_find_debuginfo(c,
663 (const unsigned char*)sbuild_id, 0,
666 close(fd); /* retaining reference by realname */
678 build_id_cache__add(const char *sbuild_id, const char *name, const char *realname,
679 struct nsinfo *nsi, bool is_kallsyms, bool is_vdso,
680 const char *proper_name, const char *root_dir)
682 const size_t size = PATH_MAX;
683 char *filename = NULL, *dir_name = NULL, *linkname = zalloc(size), *tmp;
684 char *debugfile = NULL;
690 dir_name = build_id_cache__cachedir(sbuild_id, proper_name, nsi, is_kallsyms,
695 /* Remove old style build-id cache */
696 if (is_regular_file(dir_name))
697 if (unlink(dir_name))
700 if (mkdir_p(dir_name, 0755))
703 /* Save the allocated buildid dirname */
704 if (asprintf(&filename, "%s/%s", dir_name,
705 build_id_cache__basename(is_kallsyms, is_vdso,
711 if (access(filename, F_OK)) {
713 if (copyfile("/proc/kallsyms", filename))
715 } else if (nsi && nsinfo__need_setns(nsi)) {
716 if (copyfile_ns(name, filename, nsi))
718 } else if (link(realname, filename) && errno != EEXIST) {
721 if (!(stat(name, &f_stat) < 0) &&
722 copyfile_mode(name, filename, f_stat.st_mode))
727 /* Some binaries are stripped, but have .debug files with their symbol
728 * table. Check to see if we can locate one of those, since the elf
729 * file itself may not be very useful to users of our tools without a
732 if (!is_kallsyms && !is_vdso &&
733 strncmp(".ko", name + strlen(name) - 3, 3)) {
734 debugfile = build_id_cache__find_debug(sbuild_id, nsi, root_dir);
737 if (asprintf(&filename, "%s/%s", dir_name,
738 build_id_cache__basename(false, false, true)) < 0) {
742 if (access(filename, F_OK)) {
743 if (nsi && nsinfo__need_setns(nsi)) {
744 if (copyfile_ns(debugfile, filename,
747 } else if (link(debugfile, filename) &&
749 copyfile(debugfile, filename))
755 if (!build_id_cache__linkname(sbuild_id, linkname, size))
757 tmp = strrchr(linkname, '/');
760 if (access(linkname, X_OK) && mkdir_p(linkname, 0755))
764 tmp = dir_name + strlen(buildid_dir) - 5;
765 memcpy(tmp, "../..", 5);
767 if (symlink(tmp, linkname) == 0) {
769 } else if (errno == EEXIST) {
773 len = readlink(linkname, path, sizeof(path) - 1);
775 pr_err("Can't read link: %s\n", linkname);
780 if (strcmp(tmp, path)) {
781 pr_debug("build <%s> already linked to %s\n",
782 sbuild_id, linkname);
787 /* Update SDT cache : error is just warned */
789 build_id_cache__add_sdt_cache(sbuild_id, realname, nsi) < 0)
790 pr_debug4("Failed to update/scan SDT cache for %s\n", realname);
800 int __build_id_cache__add_s(const char *sbuild_id, const char *name,
801 struct nsinfo *nsi, bool is_kallsyms, bool is_vdso,
802 const char *proper_name, const char *root_dir)
804 char *realname = NULL;
809 realname = nsinfo__realpath(name, nsi);
811 realname = realpath(name, NULL);
816 err = build_id_cache__add(sbuild_id, name, realname, nsi,
817 is_kallsyms, is_vdso, proper_name, root_dir);
824 static int build_id_cache__add_b(const struct build_id *bid,
825 const char *name, struct nsinfo *nsi,
826 bool is_kallsyms, bool is_vdso,
827 const char *proper_name,
828 const char *root_dir)
830 char sbuild_id[SBUILD_ID_SIZE];
832 build_id__sprintf(bid, sbuild_id);
834 return __build_id_cache__add_s(sbuild_id, name, nsi, is_kallsyms,
835 is_vdso, proper_name, root_dir);
838 bool build_id_cache__cached(const char *sbuild_id)
841 char *filename = build_id_cache__linkname(sbuild_id, NULL, 0);
843 if (filename && !access(filename, F_OK))
850 int build_id_cache__remove_s(const char *sbuild_id)
852 const size_t size = PATH_MAX;
853 char *filename = zalloc(size),
854 *linkname = zalloc(size), *tmp;
857 if (filename == NULL || linkname == NULL)
860 if (!build_id_cache__linkname(sbuild_id, linkname, size))
863 if (access(linkname, F_OK))
866 if (readlink(linkname, filename, size - 1) < 0)
869 if (unlink(linkname))
873 * Since the link is relative, we must make it absolute:
875 tmp = strrchr(linkname, '/') + 1;
876 snprintf(tmp, size - (tmp - linkname), "%s", filename);
888 static int filename__read_build_id_ns(const char *filename,
889 struct build_id *bid,
895 nsinfo__mountns_enter(nsi, &nsc);
896 ret = filename__read_build_id(filename, bid);
897 nsinfo__mountns_exit(&nsc);
902 static bool dso__build_id_mismatch(struct dso *dso, const char *name)
907 mutex_lock(&dso->lock);
908 if (filename__read_build_id_ns(name, &bid, dso->nsinfo) >= 0)
909 ret = !dso__build_id_equal(dso, &bid);
911 mutex_unlock(&dso->lock);
916 static int dso__cache_build_id(struct dso *dso, struct machine *machine,
917 void *priv __maybe_unused)
919 bool is_kallsyms = dso__is_kallsyms(dso);
920 bool is_vdso = dso__is_vdso(dso);
921 const char *name = dso->long_name;
922 const char *proper_name = NULL;
923 const char *root_dir = NULL;
924 char *allocated_name = NULL;
927 if (!dso->has_build_id)
930 if (dso__is_kcore(dso)) {
932 name = machine->mmap_name;
935 if (!machine__is_host(machine)) {
936 if (*machine->root_dir) {
937 root_dir = machine->root_dir;
938 ret = asprintf(&allocated_name, "%s/%s", root_dir, name);
942 name = allocated_name;
943 } else if (is_kallsyms) {
944 /* Cannot get guest kallsyms */
949 if (!is_kallsyms && dso__build_id_mismatch(dso, name))
952 mutex_lock(&dso->lock);
953 ret = build_id_cache__add_b(&dso->bid, name, dso->nsinfo,
954 is_kallsyms, is_vdso, proper_name, root_dir);
955 mutex_unlock(&dso->lock);
957 free(allocated_name);
962 machines__for_each_dso(struct machines *machines, machine__dso_t fn, void *priv)
964 int ret = machine__for_each_dso(&machines->host, fn, priv);
967 for (nd = rb_first_cached(&machines->guests); nd;
969 struct machine *pos = rb_entry(nd, struct machine, rb_node);
971 ret |= machine__for_each_dso(pos, fn, priv);
976 int __perf_session__cache_build_ids(struct perf_session *session,
977 machine__dso_t fn, void *priv)
979 if (no_buildid_cache)
982 if (mkdir(buildid_dir, 0755) != 0 && errno != EEXIST)
985 return machines__for_each_dso(&session->machines, fn, priv) ? -1 : 0;
988 int perf_session__cache_build_ids(struct perf_session *session)
990 return __perf_session__cache_build_ids(session, dso__cache_build_id, NULL);
993 static bool machine__read_build_ids(struct machine *machine, bool with_hits)
995 return __dsos__read_build_ids(&machine->dsos.head, with_hits);
998 bool perf_session__read_build_ids(struct perf_session *session, bool with_hits)
1001 bool ret = machine__read_build_ids(&session->machines.host, with_hits);
1003 for (nd = rb_first_cached(&session->machines.guests); nd;
1005 struct machine *pos = rb_entry(nd, struct machine, rb_node);
1006 ret |= machine__read_build_ids(pos, with_hits);
1012 void build_id__init(struct build_id *bid, const u8 *data, size_t size)
1014 WARN_ON(size > BUILD_ID_SIZE);
1015 memcpy(bid->data, data, size);
1019 bool build_id__is_defined(const struct build_id *bid)
1021 return bid && bid->size ? !!memchr_inv(bid->data, 0, bid->size) : false;