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;
105 for (i = 0; i < build_id->size; ++i) {
106 sprintf(bid, "%02x", *raw);
111 return (bid - bf) + 1;
114 int sysfs__sprintf_build_id(const char *root_dir, char *sbuild_id)
116 char notes[PATH_MAX];
123 scnprintf(notes, sizeof(notes), "%s/sys/kernel/notes", root_dir);
125 ret = sysfs__read_build_id(notes, &bid);
129 return build_id__sprintf(&bid, sbuild_id);
132 int filename__sprintf_build_id(const char *pathname, char *sbuild_id)
137 ret = filename__read_build_id(pathname, &bid);
141 return build_id__sprintf(&bid, sbuild_id);
144 /* asnprintf consolidates asprintf and snprintf */
145 static int asnprintf(char **strp, size_t size, const char *fmt, ...)
155 ret = vsnprintf(*strp, size, fmt, ap);
157 ret = vasprintf(strp, fmt, ap);
163 char *build_id_cache__kallsyms_path(const char *sbuild_id, char *bf,
166 bool retry_old = true;
168 snprintf(bf, size, "%s/%s/%s/kallsyms",
169 buildid_dir, DSO__NAME_KALLSYMS, sbuild_id);
171 if (!access(bf, F_OK))
174 /* Try old style kallsyms cache */
175 snprintf(bf, size, "%s/%s/%s",
176 buildid_dir, DSO__NAME_KALLSYMS, sbuild_id);
184 char *build_id_cache__linkname(const char *sbuild_id, char *bf, size_t size)
187 int ret = asnprintf(&bf, size, "%s/.build-id/%.2s/%s", buildid_dir,
188 sbuild_id, sbuild_id + 2);
189 if (ret < 0 || (tmp && size < (unsigned int)ret))
194 /* The caller is responsible to free the returned buffer. */
195 char *build_id_cache__origname(const char *sbuild_id)
199 char *ret = NULL, *p;
200 size_t offs = 5; /* == strlen("../..") */
203 linkname = build_id_cache__linkname(sbuild_id, NULL, 0);
207 len = readlink(linkname, buf, sizeof(buf) - 1);
212 /* The link should be "../..<origpath>/<sbuild_id>" */
213 p = strrchr(buf, '/'); /* Cut off the "/<sbuild_id>" */
214 if (p && (p > buf + offs)) {
216 if (buf[offs + 1] == '[')
218 * This is a DSO name, like [kernel.kallsyms].
219 * Skip the first '/', since this is not the
220 * cache of a regular file.
222 ret = strdup(buf + offs); /* Skip "../..[/]" */
229 /* Check if the given build_id cache is valid on current running system */
230 static bool build_id_cache__valid_id(char *sbuild_id)
232 char real_sbuild_id[SBUILD_ID_SIZE] = "";
237 pathname = build_id_cache__origname(sbuild_id);
241 if (!strcmp(pathname, DSO__NAME_KALLSYMS))
242 ret = sysfs__sprintf_build_id("/", real_sbuild_id);
243 else if (pathname[0] == '/')
244 ret = filename__sprintf_build_id(pathname, real_sbuild_id);
246 ret = -EINVAL; /* Should we support other special DSO cache? */
248 result = (strcmp(sbuild_id, real_sbuild_id) == 0);
254 static const char *build_id_cache__basename(bool is_kallsyms, bool is_vdso,
257 return is_kallsyms ? "kallsyms" : (is_vdso ? "vdso" : (is_debug ?
261 char *dso__build_id_filename(const struct dso *dso, char *bf, size_t size,
264 bool is_kallsyms = dso__is_kallsyms((struct dso *)dso);
265 bool is_vdso = dso__is_vdso((struct dso *)dso);
266 char sbuild_id[SBUILD_ID_SIZE];
268 bool alloc = (bf == NULL);
271 if (!dso->has_build_id)
274 build_id__sprintf(&dso->bid, sbuild_id);
275 linkname = build_id_cache__linkname(sbuild_id, NULL, 0);
279 /* Check if old style build_id cache */
280 if (is_regular_file(linkname))
281 ret = asnprintf(&bf, size, "%s", linkname);
283 ret = asnprintf(&bf, size, "%s/%s", linkname,
284 build_id_cache__basename(is_kallsyms, is_vdso,
286 if (ret < 0 || (!alloc && size < (unsigned int)ret))
293 #define dsos__for_each_with_build_id(pos, head) \
294 list_for_each_entry(pos, head, node) \
295 if (!pos->has_build_id) \
299 static int write_buildid(const char *name, size_t name_len, struct build_id *bid,
300 pid_t pid, u16 misc, struct feat_fd *fd)
303 struct perf_record_header_build_id b;
307 len = PERF_ALIGN(len, NAME_ALIGN);
309 memset(&b, 0, sizeof(b));
310 memcpy(&b.data, bid->data, bid->size);
311 b.size = (u8) bid->size;
312 misc |= PERF_RECORD_MISC_BUILD_ID_SIZE;
314 b.header.misc = misc;
315 b.header.size = sizeof(b) + len;
317 err = do_write(fd, &b, sizeof(b));
321 return write_padded(fd, name, name_len + 1, len);
324 static int machine__write_buildid_table(struct machine *machine,
329 u16 kmisc = PERF_RECORD_MISC_KERNEL,
330 umisc = PERF_RECORD_MISC_USER;
332 if (!machine__is_host(machine)) {
333 kmisc = PERF_RECORD_MISC_GUEST_KERNEL;
334 umisc = PERF_RECORD_MISC_GUEST_USER;
337 dsos__for_each_with_build_id(pos, &machine->dsos.head) {
340 bool in_kernel = false;
342 if (!pos->hit && !dso__is_vdso(pos))
345 if (dso__is_vdso(pos)) {
346 name = pos->short_name;
347 name_len = pos->short_name_len;
348 } else if (dso__is_kcore(pos)) {
349 name = machine->mmap_name;
350 name_len = strlen(name);
352 name = pos->long_name;
353 name_len = pos->long_name_len;
356 in_kernel = pos->kernel ||
357 is_kernel_module(name,
358 PERF_RECORD_MISC_CPUMODE_UNKNOWN);
359 err = write_buildid(name, name_len, &pos->bid, machine->pid,
360 in_kernel ? kmisc : umisc, fd);
368 int perf_session__write_buildid_table(struct perf_session *session,
372 int err = machine__write_buildid_table(&session->machines.host, fd);
377 for (nd = rb_first_cached(&session->machines.guests); nd;
379 struct machine *pos = rb_entry(nd, struct machine, rb_node);
380 err = machine__write_buildid_table(pos, fd);
387 static int __dsos__hit_all(struct list_head *head)
391 list_for_each_entry(pos, head, node)
397 static int machine__hit_all_dsos(struct machine *machine)
399 return __dsos__hit_all(&machine->dsos.head);
402 int dsos__hit_all(struct perf_session *session)
407 err = machine__hit_all_dsos(&session->machines.host);
411 for (nd = rb_first_cached(&session->machines.guests); nd;
413 struct machine *pos = rb_entry(nd, struct machine, rb_node);
415 err = machine__hit_all_dsos(pos);
423 void disable_buildid_cache(void)
425 no_buildid_cache = true;
428 static bool lsdir_bid_head_filter(const char *name __maybe_unused,
431 return (strlen(d->d_name) == 2) &&
432 isxdigit(d->d_name[0]) && isxdigit(d->d_name[1]);
435 static bool lsdir_bid_tail_filter(const char *name __maybe_unused,
439 while (isxdigit(d->d_name[i]) && i < SBUILD_ID_SIZE - 3)
441 return (i == SBUILD_ID_SIZE - 3) && (d->d_name[i] == '\0');
444 struct strlist *build_id_cache__list_all(bool validonly)
446 struct strlist *toplist, *linklist = NULL, *bidlist;
447 struct str_node *nd, *nd2;
448 char *topdir, *linkdir = NULL;
449 char sbuild_id[SBUILD_ID_SIZE];
451 /* for filename__ functions */
455 /* Open the top-level directory */
456 if (asprintf(&topdir, "%s/.build-id/", buildid_dir) < 0)
459 bidlist = strlist__new(NULL, NULL);
463 toplist = lsdir(topdir, lsdir_bid_head_filter);
465 pr_debug("Error in lsdir(%s): %d\n", topdir, errno);
466 /* If there is no buildid cache, return an empty list */
472 strlist__for_each_entry(nd, toplist) {
473 if (asprintf(&linkdir, "%s/%s", topdir, nd->s) < 0)
475 /* Open the lower-level directory */
476 linklist = lsdir(linkdir, lsdir_bid_tail_filter);
478 pr_debug("Error in lsdir(%s): %d\n", linkdir, errno);
481 strlist__for_each_entry(nd2, linklist) {
482 if (snprintf(sbuild_id, SBUILD_ID_SIZE, "%s%s",
483 nd->s, nd2->s) != SBUILD_ID_SIZE - 1)
485 if (validonly && !build_id_cache__valid_id(sbuild_id))
487 if (strlist__add(bidlist, sbuild_id) < 0)
490 strlist__delete(linklist);
495 strlist__delete(toplist);
502 strlist__delete(linklist);
504 strlist__delete(bidlist);
509 static bool str_is_build_id(const char *maybe_sbuild_id, size_t len)
513 for (i = 0; i < len; i++) {
514 if (!isxdigit(maybe_sbuild_id[i]))
520 /* Return the valid complete build-id */
521 char *build_id_cache__complement(const char *incomplete_sbuild_id)
523 struct strlist *bidlist;
524 struct str_node *nd, *cand = NULL;
525 char *sbuild_id = NULL;
526 size_t len = strlen(incomplete_sbuild_id);
528 if (len >= SBUILD_ID_SIZE ||
529 !str_is_build_id(incomplete_sbuild_id, len))
532 bidlist = build_id_cache__list_all(true);
536 strlist__for_each_entry(nd, bidlist) {
537 if (strncmp(nd->s, incomplete_sbuild_id, len) != 0)
539 if (cand) { /* Error: There are more than 2 candidates. */
546 sbuild_id = strdup(cand->s);
547 strlist__delete(bidlist);
552 char *build_id_cache__cachedir(const char *sbuild_id, const char *name,
553 struct nsinfo *nsi, bool is_kallsyms,
556 char *realname = (char *)name, *filename;
557 bool slash = is_kallsyms || is_vdso;
560 realname = nsinfo__realpath(name, nsi);
565 if (asprintf(&filename, "%s%s%s%s%s", buildid_dir, slash ? "/" : "",
566 is_vdso ? DSO__NAME_VDSO : realname,
567 sbuild_id ? "/" : "", sbuild_id ?: "") < 0)
576 int build_id_cache__list_build_ids(const char *pathname, struct nsinfo *nsi,
577 struct strlist **result)
582 dir_name = build_id_cache__cachedir(NULL, pathname, nsi, false, false);
586 *result = lsdir(dir_name, lsdir_no_dot_filter);
594 #if defined(HAVE_LIBELF_SUPPORT) && defined(HAVE_GELF_GETNOTE_SUPPORT)
595 static int build_id_cache__add_sdt_cache(const char *sbuild_id,
596 const char *realname,
599 struct probe_cache *cache;
603 cache = probe_cache__new(sbuild_id, nsi);
607 nsinfo__mountns_enter(nsi, &nsc);
608 ret = probe_cache__scan_sdt(cache, realname);
609 nsinfo__mountns_exit(&nsc);
611 pr_debug4("Found %d SDTs in %s\n", ret, realname);
612 if (probe_cache__commit(cache) < 0)
615 probe_cache__delete(cache);
619 #define build_id_cache__add_sdt_cache(sbuild_id, realname, nsi) (0)
622 static char *build_id_cache__find_debug(const char *sbuild_id,
625 char *realname = NULL;
630 debugfile = calloc(1, PATH_MAX);
634 len = __symbol__join_symfs(debugfile, PATH_MAX,
635 "/usr/lib/debug/.build-id/");
636 snprintf(debugfile + len, PATH_MAX - len, "%.2s/%s.debug", sbuild_id,
639 nsinfo__mountns_enter(nsi, &nsc);
640 realname = realpath(debugfile, NULL);
641 if (realname && access(realname, R_OK))
643 nsinfo__mountns_exit(&nsc);
645 #ifdef HAVE_DEBUGINFOD_SUPPORT
646 if (realname == NULL) {
647 debuginfod_client* c = debuginfod_begin();
649 int fd = debuginfod_find_debuginfo(c,
650 (const unsigned char*)sbuild_id, 0,
653 close(fd); /* retaining reference by realname */
664 int build_id_cache__add_s(const char *sbuild_id, const char *name,
665 struct nsinfo *nsi, bool is_kallsyms, bool is_vdso)
667 const size_t size = PATH_MAX;
668 char *realname = NULL, *filename = NULL, *dir_name = NULL,
669 *linkname = zalloc(size), *tmp;
670 char *debugfile = NULL;
675 realname = nsinfo__realpath(name, nsi);
677 realname = realpath(name, NULL);
682 dir_name = build_id_cache__cachedir(sbuild_id, name, nsi, is_kallsyms,
687 /* Remove old style build-id cache */
688 if (is_regular_file(dir_name))
689 if (unlink(dir_name))
692 if (mkdir_p(dir_name, 0755))
695 /* Save the allocated buildid dirname */
696 if (asprintf(&filename, "%s/%s", dir_name,
697 build_id_cache__basename(is_kallsyms, is_vdso,
703 if (access(filename, F_OK)) {
705 if (copyfile("/proc/kallsyms", filename))
707 } else if (nsi && nsi->need_setns) {
708 if (copyfile_ns(name, filename, nsi))
710 } else if (link(realname, filename) && errno != EEXIST &&
711 copyfile(name, filename))
715 /* Some binaries are stripped, but have .debug files with their symbol
716 * table. Check to see if we can locate one of those, since the elf
717 * file itself may not be very useful to users of our tools without a
720 if (!is_kallsyms && !is_vdso &&
721 strncmp(".ko", name + strlen(name) - 3, 3)) {
722 debugfile = build_id_cache__find_debug(sbuild_id, nsi);
725 if (asprintf(&filename, "%s/%s", dir_name,
726 build_id_cache__basename(false, false, true)) < 0) {
730 if (access(filename, F_OK)) {
731 if (nsi && nsi->need_setns) {
732 if (copyfile_ns(debugfile, filename,
735 } else if (link(debugfile, filename) &&
737 copyfile(debugfile, filename))
743 if (!build_id_cache__linkname(sbuild_id, linkname, size))
745 tmp = strrchr(linkname, '/');
748 if (access(linkname, X_OK) && mkdir_p(linkname, 0755))
752 tmp = dir_name + strlen(buildid_dir) - 5;
753 memcpy(tmp, "../..", 5);
755 if (symlink(tmp, linkname) == 0)
758 /* Update SDT cache : error is just warned */
760 build_id_cache__add_sdt_cache(sbuild_id, realname, nsi) < 0)
761 pr_debug4("Failed to update/scan SDT cache for %s\n", realname);
773 static int build_id_cache__add_b(const struct build_id *bid,
774 const char *name, struct nsinfo *nsi,
775 bool is_kallsyms, bool is_vdso)
777 char sbuild_id[SBUILD_ID_SIZE];
779 build_id__sprintf(bid, sbuild_id);
781 return build_id_cache__add_s(sbuild_id, name, nsi, is_kallsyms,
785 bool build_id_cache__cached(const char *sbuild_id)
788 char *filename = build_id_cache__linkname(sbuild_id, NULL, 0);
790 if (filename && !access(filename, F_OK))
797 int build_id_cache__remove_s(const char *sbuild_id)
799 const size_t size = PATH_MAX;
800 char *filename = zalloc(size),
801 *linkname = zalloc(size), *tmp;
804 if (filename == NULL || linkname == NULL)
807 if (!build_id_cache__linkname(sbuild_id, linkname, size))
810 if (access(linkname, F_OK))
813 if (readlink(linkname, filename, size - 1) < 0)
816 if (unlink(linkname))
820 * Since the link is relative, we must make it absolute:
822 tmp = strrchr(linkname, '/') + 1;
823 snprintf(tmp, size - (tmp - linkname), "%s", filename);
835 static int dso__cache_build_id(struct dso *dso, struct machine *machine)
837 bool is_kallsyms = dso__is_kallsyms(dso);
838 bool is_vdso = dso__is_vdso(dso);
839 const char *name = dso->long_name;
841 if (dso__is_kcore(dso)) {
843 name = machine->mmap_name;
845 return build_id_cache__add_b(&dso->bid, name, dso->nsinfo,
846 is_kallsyms, is_vdso);
849 static int __dsos__cache_build_ids(struct list_head *head,
850 struct machine *machine)
855 dsos__for_each_with_build_id(pos, head)
856 if (dso__cache_build_id(pos, machine))
862 static int machine__cache_build_ids(struct machine *machine)
864 return __dsos__cache_build_ids(&machine->dsos.head, machine);
867 int perf_session__cache_build_ids(struct perf_session *session)
872 if (no_buildid_cache)
875 if (mkdir(buildid_dir, 0755) != 0 && errno != EEXIST)
878 ret = machine__cache_build_ids(&session->machines.host);
880 for (nd = rb_first_cached(&session->machines.guests); nd;
882 struct machine *pos = rb_entry(nd, struct machine, rb_node);
883 ret |= machine__cache_build_ids(pos);
888 static bool machine__read_build_ids(struct machine *machine, bool with_hits)
890 return __dsos__read_build_ids(&machine->dsos.head, with_hits);
893 bool perf_session__read_build_ids(struct perf_session *session, bool with_hits)
896 bool ret = machine__read_build_ids(&session->machines.host, with_hits);
898 for (nd = rb_first_cached(&session->machines.guests); nd;
900 struct machine *pos = rb_entry(nd, struct machine, rb_node);
901 ret |= machine__read_build_ids(pos, with_hits);
907 void build_id__init(struct build_id *bid, const u8 *data, size_t size)
909 WARN_ON(size > BUILD_ID_SIZE);
910 memcpy(bid->data, data, size);