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" // copyfile_ns(), lsdir(), mkdir_p(), rm_rf()
15 #include <sys/types.h>
19 #include "namespaces.h"
23 #include <linux/kernel.h>
30 #include "probe-file.h"
33 #include <linux/ctype.h>
34 #include <linux/zalloc.h>
36 static bool no_buildid_cache;
38 int build_id__mark_dso_hit(struct perf_tool *tool __maybe_unused,
39 union perf_event *event,
40 struct perf_sample *sample,
41 struct evsel *evsel __maybe_unused,
42 struct machine *machine)
44 struct addr_location al;
45 struct thread *thread = machine__findnew_thread(machine, sample->pid,
49 pr_err("problem processing %d event, skipping it.\n",
54 if (thread__find_map(thread, sample->cpumode, sample->ip, &al))
61 static int perf_event__exit_del_thread(struct perf_tool *tool __maybe_unused,
62 union perf_event *event,
63 struct perf_sample *sample
65 struct machine *machine)
67 struct thread *thread = machine__findnew_thread(machine,
71 dump_printf("(%d:%d):(%d:%d)\n", event->fork.pid, event->fork.tid,
72 event->fork.ppid, event->fork.ptid);
75 machine__remove_thread(machine, thread);
82 struct perf_tool build_id__mark_dso_hit_ops = {
83 .sample = build_id__mark_dso_hit,
84 .mmap = perf_event__process_mmap,
85 .mmap2 = perf_event__process_mmap2,
86 .fork = perf_event__process_fork,
87 .exit = perf_event__exit_del_thread,
88 .attr = perf_event__process_attr,
89 .build_id = perf_event__process_build_id,
90 .ordered_events = true,
93 int build_id__sprintf(const u8 *build_id, int len, char *bf)
96 const u8 *raw = build_id;
99 for (i = 0; i < len; ++i) {
100 sprintf(bid, "%02x", *raw);
105 return (bid - bf) + 1;
108 int sysfs__sprintf_build_id(const char *root_dir, char *sbuild_id)
110 char notes[PATH_MAX];
111 u8 build_id[BUILD_ID_SIZE];
117 scnprintf(notes, sizeof(notes), "%s/sys/kernel/notes", root_dir);
119 ret = sysfs__read_build_id(notes, build_id, sizeof(build_id));
123 return build_id__sprintf(build_id, sizeof(build_id), sbuild_id);
126 int filename__sprintf_build_id(const char *pathname, char *sbuild_id)
128 u8 build_id[BUILD_ID_SIZE];
131 ret = filename__read_build_id(pathname, build_id, sizeof(build_id));
134 else if (ret != sizeof(build_id))
137 return build_id__sprintf(build_id, sizeof(build_id), sbuild_id);
140 /* asnprintf consolidates asprintf and snprintf */
141 static int asnprintf(char **strp, size_t size, const char *fmt, ...)
151 ret = vsnprintf(*strp, size, fmt, ap);
153 ret = vasprintf(strp, fmt, ap);
159 char *build_id_cache__kallsyms_path(const char *sbuild_id, char *bf,
162 bool retry_old = true;
164 snprintf(bf, size, "%s/%s/%s/kallsyms",
165 buildid_dir, DSO__NAME_KALLSYMS, sbuild_id);
167 if (!access(bf, F_OK))
170 /* Try old style kallsyms cache */
171 snprintf(bf, size, "%s/%s/%s",
172 buildid_dir, DSO__NAME_KALLSYMS, sbuild_id);
180 char *build_id_cache__linkname(const char *sbuild_id, char *bf, size_t size)
183 int ret = asnprintf(&bf, size, "%s/.build-id/%.2s/%s", buildid_dir,
184 sbuild_id, sbuild_id + 2);
185 if (ret < 0 || (tmp && size < (unsigned int)ret))
190 /* The caller is responsible to free the returned buffer. */
191 char *build_id_cache__origname(const char *sbuild_id)
195 char *ret = NULL, *p;
196 size_t offs = 5; /* == strlen("../..") */
199 linkname = build_id_cache__linkname(sbuild_id, NULL, 0);
203 len = readlink(linkname, buf, sizeof(buf) - 1);
208 /* The link should be "../..<origpath>/<sbuild_id>" */
209 p = strrchr(buf, '/'); /* Cut off the "/<sbuild_id>" */
210 if (p && (p > buf + offs)) {
212 if (buf[offs + 1] == '[')
214 * This is a DSO name, like [kernel.kallsyms].
215 * Skip the first '/', since this is not the
216 * cache of a regular file.
218 ret = strdup(buf + offs); /* Skip "../..[/]" */
225 /* Check if the given build_id cache is valid on current running system */
226 static bool build_id_cache__valid_id(char *sbuild_id)
228 char real_sbuild_id[SBUILD_ID_SIZE] = "";
233 pathname = build_id_cache__origname(sbuild_id);
237 if (!strcmp(pathname, DSO__NAME_KALLSYMS))
238 ret = sysfs__sprintf_build_id("/", real_sbuild_id);
239 else if (pathname[0] == '/')
240 ret = filename__sprintf_build_id(pathname, real_sbuild_id);
242 ret = -EINVAL; /* Should we support other special DSO cache? */
244 result = (strcmp(sbuild_id, real_sbuild_id) == 0);
250 static const char *build_id_cache__basename(bool is_kallsyms, bool is_vdso,
253 return is_kallsyms ? "kallsyms" : (is_vdso ? "vdso" : (is_debug ?
257 char *dso__build_id_filename(const struct dso *dso, char *bf, size_t size,
260 bool is_kallsyms = dso__is_kallsyms((struct dso *)dso);
261 bool is_vdso = dso__is_vdso((struct dso *)dso);
262 char sbuild_id[SBUILD_ID_SIZE];
264 bool alloc = (bf == NULL);
267 if (!dso->has_build_id)
270 build_id__sprintf(dso->build_id, sizeof(dso->build_id), sbuild_id);
271 linkname = build_id_cache__linkname(sbuild_id, NULL, 0);
275 /* Check if old style build_id cache */
276 if (is_regular_file(linkname))
277 ret = asnprintf(&bf, size, "%s", linkname);
279 ret = asnprintf(&bf, size, "%s/%s", linkname,
280 build_id_cache__basename(is_kallsyms, is_vdso,
282 if (ret < 0 || (!alloc && size < (unsigned int)ret))
289 #define dsos__for_each_with_build_id(pos, head) \
290 list_for_each_entry(pos, head, node) \
291 if (!pos->has_build_id) \
295 static int write_buildid(const char *name, size_t name_len, u8 *build_id,
296 pid_t pid, u16 misc, struct feat_fd *fd)
299 struct perf_record_header_build_id b;
303 len = PERF_ALIGN(len, NAME_ALIGN);
305 memset(&b, 0, sizeof(b));
306 memcpy(&b.build_id, build_id, BUILD_ID_SIZE);
308 b.header.misc = misc;
309 b.header.size = sizeof(b) + len;
311 err = do_write(fd, &b, sizeof(b));
315 return write_padded(fd, name, name_len + 1, len);
318 static int machine__write_buildid_table(struct machine *machine,
323 u16 kmisc = PERF_RECORD_MISC_KERNEL,
324 umisc = PERF_RECORD_MISC_USER;
326 if (!machine__is_host(machine)) {
327 kmisc = PERF_RECORD_MISC_GUEST_KERNEL;
328 umisc = PERF_RECORD_MISC_GUEST_USER;
331 dsos__for_each_with_build_id(pos, &machine->dsos.head) {
334 bool in_kernel = false;
336 if (!pos->hit && !dso__is_vdso(pos))
339 if (dso__is_vdso(pos)) {
340 name = pos->short_name;
341 name_len = pos->short_name_len;
342 } else if (dso__is_kcore(pos)) {
343 name = machine->mmap_name;
344 name_len = strlen(name);
346 name = pos->long_name;
347 name_len = pos->long_name_len;
350 in_kernel = pos->kernel ||
351 is_kernel_module(name,
352 PERF_RECORD_MISC_CPUMODE_UNKNOWN);
353 err = write_buildid(name, name_len, pos->build_id, machine->pid,
354 in_kernel ? kmisc : umisc, fd);
362 int perf_session__write_buildid_table(struct perf_session *session,
366 int err = machine__write_buildid_table(&session->machines.host, fd);
371 for (nd = rb_first_cached(&session->machines.guests); nd;
373 struct machine *pos = rb_entry(nd, struct machine, rb_node);
374 err = machine__write_buildid_table(pos, fd);
381 static int __dsos__hit_all(struct list_head *head)
385 list_for_each_entry(pos, head, node)
391 static int machine__hit_all_dsos(struct machine *machine)
393 return __dsos__hit_all(&machine->dsos.head);
396 int dsos__hit_all(struct perf_session *session)
401 err = machine__hit_all_dsos(&session->machines.host);
405 for (nd = rb_first_cached(&session->machines.guests); nd;
407 struct machine *pos = rb_entry(nd, struct machine, rb_node);
409 err = machine__hit_all_dsos(pos);
417 void disable_buildid_cache(void)
419 no_buildid_cache = true;
422 static bool lsdir_bid_head_filter(const char *name __maybe_unused,
425 return (strlen(d->d_name) == 2) &&
426 isxdigit(d->d_name[0]) && isxdigit(d->d_name[1]);
429 static bool lsdir_bid_tail_filter(const char *name __maybe_unused,
433 while (isxdigit(d->d_name[i]) && i < SBUILD_ID_SIZE - 3)
435 return (i == SBUILD_ID_SIZE - 3) && (d->d_name[i] == '\0');
438 struct strlist *build_id_cache__list_all(bool validonly)
440 struct strlist *toplist, *linklist = NULL, *bidlist;
441 struct str_node *nd, *nd2;
442 char *topdir, *linkdir = NULL;
443 char sbuild_id[SBUILD_ID_SIZE];
445 /* for filename__ functions */
449 /* Open the top-level directory */
450 if (asprintf(&topdir, "%s/.build-id/", buildid_dir) < 0)
453 bidlist = strlist__new(NULL, NULL);
457 toplist = lsdir(topdir, lsdir_bid_head_filter);
459 pr_debug("Error in lsdir(%s): %d\n", topdir, errno);
460 /* If there is no buildid cache, return an empty list */
466 strlist__for_each_entry(nd, toplist) {
467 if (asprintf(&linkdir, "%s/%s", topdir, nd->s) < 0)
469 /* Open the lower-level directory */
470 linklist = lsdir(linkdir, lsdir_bid_tail_filter);
472 pr_debug("Error in lsdir(%s): %d\n", linkdir, errno);
475 strlist__for_each_entry(nd2, linklist) {
476 if (snprintf(sbuild_id, SBUILD_ID_SIZE, "%s%s",
477 nd->s, nd2->s) != SBUILD_ID_SIZE - 1)
479 if (validonly && !build_id_cache__valid_id(sbuild_id))
481 if (strlist__add(bidlist, sbuild_id) < 0)
484 strlist__delete(linklist);
489 strlist__delete(toplist);
496 strlist__delete(linklist);
498 strlist__delete(bidlist);
503 static bool str_is_build_id(const char *maybe_sbuild_id, size_t len)
507 for (i = 0; i < len; i++) {
508 if (!isxdigit(maybe_sbuild_id[i]))
514 /* Return the valid complete build-id */
515 char *build_id_cache__complement(const char *incomplete_sbuild_id)
517 struct strlist *bidlist;
518 struct str_node *nd, *cand = NULL;
519 char *sbuild_id = NULL;
520 size_t len = strlen(incomplete_sbuild_id);
522 if (len >= SBUILD_ID_SIZE ||
523 !str_is_build_id(incomplete_sbuild_id, len))
526 bidlist = build_id_cache__list_all(true);
530 strlist__for_each_entry(nd, bidlist) {
531 if (strncmp(nd->s, incomplete_sbuild_id, len) != 0)
533 if (cand) { /* Error: There are more than 2 candidates. */
540 sbuild_id = strdup(cand->s);
541 strlist__delete(bidlist);
546 char *build_id_cache__cachedir(const char *sbuild_id, const char *name,
547 struct nsinfo *nsi, bool is_kallsyms,
550 char *realname = (char *)name, *filename;
551 bool slash = is_kallsyms || is_vdso;
554 realname = nsinfo__realpath(name, nsi);
559 if (asprintf(&filename, "%s%s%s%s%s", buildid_dir, slash ? "/" : "",
560 is_vdso ? DSO__NAME_VDSO : realname,
561 sbuild_id ? "/" : "", sbuild_id ?: "") < 0)
570 int build_id_cache__list_build_ids(const char *pathname, struct nsinfo *nsi,
571 struct strlist **result)
576 dir_name = build_id_cache__cachedir(NULL, pathname, nsi, false, false);
580 *result = lsdir(dir_name, lsdir_no_dot_filter);
588 #if defined(HAVE_LIBELF_SUPPORT) && defined(HAVE_GELF_GETNOTE_SUPPORT)
589 static int build_id_cache__add_sdt_cache(const char *sbuild_id,
590 const char *realname,
593 struct probe_cache *cache;
597 cache = probe_cache__new(sbuild_id, nsi);
601 nsinfo__mountns_enter(nsi, &nsc);
602 ret = probe_cache__scan_sdt(cache, realname);
603 nsinfo__mountns_exit(&nsc);
605 pr_debug4("Found %d SDTs in %s\n", ret, realname);
606 if (probe_cache__commit(cache) < 0)
609 probe_cache__delete(cache);
613 #define build_id_cache__add_sdt_cache(sbuild_id, realname, nsi) (0)
616 static char *build_id_cache__find_debug(const char *sbuild_id,
619 char *realname = NULL;
624 debugfile = calloc(1, PATH_MAX);
628 len = __symbol__join_symfs(debugfile, PATH_MAX,
629 "/usr/lib/debug/.build-id/");
630 snprintf(debugfile + len, PATH_MAX - len, "%.2s/%s.debug", sbuild_id,
633 nsinfo__mountns_enter(nsi, &nsc);
634 realname = realpath(debugfile, NULL);
635 if (realname && access(realname, R_OK))
637 nsinfo__mountns_exit(&nsc);
643 int build_id_cache__add_s(const char *sbuild_id, const char *name,
644 struct nsinfo *nsi, bool is_kallsyms, bool is_vdso)
646 const size_t size = PATH_MAX;
647 char *realname = NULL, *filename = NULL, *dir_name = NULL,
648 *linkname = zalloc(size), *tmp;
649 char *debugfile = NULL;
654 realname = nsinfo__realpath(name, nsi);
656 realname = realpath(name, NULL);
661 dir_name = build_id_cache__cachedir(sbuild_id, name, nsi, is_kallsyms,
666 /* Remove old style build-id cache */
667 if (is_regular_file(dir_name))
668 if (unlink(dir_name))
671 if (mkdir_p(dir_name, 0755))
674 /* Save the allocated buildid dirname */
675 if (asprintf(&filename, "%s/%s", dir_name,
676 build_id_cache__basename(is_kallsyms, is_vdso,
682 if (access(filename, F_OK)) {
684 if (copyfile("/proc/kallsyms", filename))
686 } else if (nsi && nsi->need_setns) {
687 if (copyfile_ns(name, filename, nsi))
689 } else if (link(realname, filename) && errno != EEXIST &&
690 copyfile(name, filename))
694 /* Some binaries are stripped, but have .debug files with their symbol
695 * table. Check to see if we can locate one of those, since the elf
696 * file itself may not be very useful to users of our tools without a
699 if (!is_kallsyms && !is_vdso &&
700 strncmp(".ko", name + strlen(name) - 3, 3)) {
701 debugfile = build_id_cache__find_debug(sbuild_id, nsi);
704 if (asprintf(&filename, "%s/%s", dir_name,
705 build_id_cache__basename(false, false, true)) < 0) {
709 if (access(filename, F_OK)) {
710 if (nsi && nsi->need_setns) {
711 if (copyfile_ns(debugfile, filename,
714 } else if (link(debugfile, filename) &&
716 copyfile(debugfile, filename))
722 if (!build_id_cache__linkname(sbuild_id, linkname, size))
724 tmp = strrchr(linkname, '/');
727 if (access(linkname, X_OK) && mkdir_p(linkname, 0755))
731 tmp = dir_name + strlen(buildid_dir) - 5;
732 memcpy(tmp, "../..", 5);
734 if (symlink(tmp, linkname) == 0)
737 /* Update SDT cache : error is just warned */
739 build_id_cache__add_sdt_cache(sbuild_id, realname, nsi) < 0)
740 pr_debug4("Failed to update/scan SDT cache for %s\n", realname);
752 static int build_id_cache__add_b(const u8 *build_id, size_t build_id_size,
753 const char *name, struct nsinfo *nsi,
754 bool is_kallsyms, bool is_vdso)
756 char sbuild_id[SBUILD_ID_SIZE];
758 build_id__sprintf(build_id, build_id_size, sbuild_id);
760 return build_id_cache__add_s(sbuild_id, name, nsi, is_kallsyms,
764 bool build_id_cache__cached(const char *sbuild_id)
767 char *filename = build_id_cache__linkname(sbuild_id, NULL, 0);
769 if (filename && !access(filename, F_OK))
776 int build_id_cache__remove_s(const char *sbuild_id)
778 const size_t size = PATH_MAX;
779 char *filename = zalloc(size),
780 *linkname = zalloc(size), *tmp;
783 if (filename == NULL || linkname == NULL)
786 if (!build_id_cache__linkname(sbuild_id, linkname, size))
789 if (access(linkname, F_OK))
792 if (readlink(linkname, filename, size - 1) < 0)
795 if (unlink(linkname))
799 * Since the link is relative, we must make it absolute:
801 tmp = strrchr(linkname, '/') + 1;
802 snprintf(tmp, size - (tmp - linkname), "%s", filename);
814 static int dso__cache_build_id(struct dso *dso, struct machine *machine)
816 bool is_kallsyms = dso__is_kallsyms(dso);
817 bool is_vdso = dso__is_vdso(dso);
818 const char *name = dso->long_name;
820 if (dso__is_kcore(dso)) {
822 name = machine->mmap_name;
824 return build_id_cache__add_b(dso->build_id, sizeof(dso->build_id), name,
825 dso->nsinfo, is_kallsyms, is_vdso);
828 static int __dsos__cache_build_ids(struct list_head *head,
829 struct machine *machine)
834 dsos__for_each_with_build_id(pos, head)
835 if (dso__cache_build_id(pos, machine))
841 static int machine__cache_build_ids(struct machine *machine)
843 return __dsos__cache_build_ids(&machine->dsos.head, machine);
846 int perf_session__cache_build_ids(struct perf_session *session)
851 if (no_buildid_cache)
854 if (mkdir(buildid_dir, 0755) != 0 && errno != EEXIST)
857 ret = machine__cache_build_ids(&session->machines.host);
859 for (nd = rb_first_cached(&session->machines.guests); nd;
861 struct machine *pos = rb_entry(nd, struct machine, rb_node);
862 ret |= machine__cache_build_ids(pos);
867 static bool machine__read_build_ids(struct machine *machine, bool with_hits)
869 return __dsos__read_build_ids(&machine->dsos.head, with_hits);
872 bool perf_session__read_build_ids(struct perf_session *session, bool with_hits)
875 bool ret = machine__read_build_ids(&session->machines.host, with_hits);
877 for (nd = rb_first_cached(&session->machines.guests); nd;
879 struct machine *pos = rb_entry(nd, struct machine, rb_node);
880 ret |= machine__read_build_ids(pos, with_hits);