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>
15 #include <sys/types.h>
18 #include "namespaces.h"
22 #include <linux/kernel.h>
29 #include "probe-file.h"
32 #include <linux/ctype.h>
34 static bool no_buildid_cache;
36 int build_id__mark_dso_hit(struct perf_tool *tool __maybe_unused,
37 union perf_event *event,
38 struct perf_sample *sample,
39 struct perf_evsel *evsel __maybe_unused,
40 struct machine *machine)
42 struct addr_location al;
43 struct thread *thread = machine__findnew_thread(machine, sample->pid,
47 pr_err("problem processing %d event, skipping it.\n",
52 if (thread__find_map(thread, sample->cpumode, sample->ip, &al))
59 static int perf_event__exit_del_thread(struct perf_tool *tool __maybe_unused,
60 union perf_event *event,
61 struct perf_sample *sample
63 struct machine *machine)
65 struct thread *thread = machine__findnew_thread(machine,
69 dump_printf("(%d:%d):(%d:%d)\n", event->fork.pid, event->fork.tid,
70 event->fork.ppid, event->fork.ptid);
73 machine__remove_thread(machine, thread);
80 struct perf_tool build_id__mark_dso_hit_ops = {
81 .sample = build_id__mark_dso_hit,
82 .mmap = perf_event__process_mmap,
83 .mmap2 = perf_event__process_mmap2,
84 .fork = perf_event__process_fork,
85 .exit = perf_event__exit_del_thread,
86 .attr = perf_event__process_attr,
87 .build_id = perf_event__process_build_id,
88 .ordered_events = true,
91 int build_id__sprintf(const u8 *build_id, int len, char *bf)
94 const u8 *raw = build_id;
97 for (i = 0; i < len; ++i) {
98 sprintf(bid, "%02x", *raw);
103 return (bid - bf) + 1;
106 int sysfs__sprintf_build_id(const char *root_dir, char *sbuild_id)
108 char notes[PATH_MAX];
109 u8 build_id[BUILD_ID_SIZE];
115 scnprintf(notes, sizeof(notes), "%s/sys/kernel/notes", root_dir);
117 ret = sysfs__read_build_id(notes, build_id, sizeof(build_id));
121 return build_id__sprintf(build_id, sizeof(build_id), sbuild_id);
124 int filename__sprintf_build_id(const char *pathname, char *sbuild_id)
126 u8 build_id[BUILD_ID_SIZE];
129 ret = filename__read_build_id(pathname, build_id, sizeof(build_id));
132 else if (ret != sizeof(build_id))
135 return build_id__sprintf(build_id, sizeof(build_id), sbuild_id);
138 /* asnprintf consolidates asprintf and snprintf */
139 static int asnprintf(char **strp, size_t size, const char *fmt, ...)
149 ret = vsnprintf(*strp, size, fmt, ap);
151 ret = vasprintf(strp, fmt, ap);
157 char *build_id_cache__kallsyms_path(const char *sbuild_id, char *bf,
160 bool retry_old = true;
162 snprintf(bf, size, "%s/%s/%s/kallsyms",
163 buildid_dir, DSO__NAME_KALLSYMS, sbuild_id);
165 if (!access(bf, F_OK))
168 /* Try old style kallsyms cache */
169 snprintf(bf, size, "%s/%s/%s",
170 buildid_dir, DSO__NAME_KALLSYMS, sbuild_id);
178 char *build_id_cache__linkname(const char *sbuild_id, char *bf, size_t size)
181 int ret = asnprintf(&bf, size, "%s/.build-id/%.2s/%s", buildid_dir,
182 sbuild_id, sbuild_id + 2);
183 if (ret < 0 || (tmp && size < (unsigned int)ret))
188 /* The caller is responsible to free the returned buffer. */
189 char *build_id_cache__origname(const char *sbuild_id)
193 char *ret = NULL, *p;
194 size_t offs = 5; /* == strlen("../..") */
197 linkname = build_id_cache__linkname(sbuild_id, NULL, 0);
201 len = readlink(linkname, buf, sizeof(buf) - 1);
206 /* The link should be "../..<origpath>/<sbuild_id>" */
207 p = strrchr(buf, '/'); /* Cut off the "/<sbuild_id>" */
208 if (p && (p > buf + offs)) {
210 if (buf[offs + 1] == '[')
212 * This is a DSO name, like [kernel.kallsyms].
213 * Skip the first '/', since this is not the
214 * cache of a regular file.
216 ret = strdup(buf + offs); /* Skip "../..[/]" */
223 /* Check if the given build_id cache is valid on current running system */
224 static bool build_id_cache__valid_id(char *sbuild_id)
226 char real_sbuild_id[SBUILD_ID_SIZE] = "";
231 pathname = build_id_cache__origname(sbuild_id);
235 if (!strcmp(pathname, DSO__NAME_KALLSYMS))
236 ret = sysfs__sprintf_build_id("/", real_sbuild_id);
237 else if (pathname[0] == '/')
238 ret = filename__sprintf_build_id(pathname, real_sbuild_id);
240 ret = -EINVAL; /* Should we support other special DSO cache? */
242 result = (strcmp(sbuild_id, real_sbuild_id) == 0);
248 static const char *build_id_cache__basename(bool is_kallsyms, bool is_vdso,
251 return is_kallsyms ? "kallsyms" : (is_vdso ? "vdso" : (is_debug ?
255 char *dso__build_id_filename(const struct dso *dso, char *bf, size_t size,
258 bool is_kallsyms = dso__is_kallsyms((struct dso *)dso);
259 bool is_vdso = dso__is_vdso((struct dso *)dso);
260 char sbuild_id[SBUILD_ID_SIZE];
262 bool alloc = (bf == NULL);
265 if (!dso->has_build_id)
268 build_id__sprintf(dso->build_id, sizeof(dso->build_id), sbuild_id);
269 linkname = build_id_cache__linkname(sbuild_id, NULL, 0);
273 /* Check if old style build_id cache */
274 if (is_regular_file(linkname))
275 ret = asnprintf(&bf, size, "%s", linkname);
277 ret = asnprintf(&bf, size, "%s/%s", linkname,
278 build_id_cache__basename(is_kallsyms, is_vdso,
280 if (ret < 0 || (!alloc && size < (unsigned int)ret))
287 #define dsos__for_each_with_build_id(pos, head) \
288 list_for_each_entry(pos, head, node) \
289 if (!pos->has_build_id) \
293 static int write_buildid(const char *name, size_t name_len, u8 *build_id,
294 pid_t pid, u16 misc, struct feat_fd *fd)
297 struct build_id_event b;
301 len = PERF_ALIGN(len, NAME_ALIGN);
303 memset(&b, 0, sizeof(b));
304 memcpy(&b.build_id, build_id, BUILD_ID_SIZE);
306 b.header.misc = misc;
307 b.header.size = sizeof(b) + len;
309 err = do_write(fd, &b, sizeof(b));
313 return write_padded(fd, name, name_len + 1, len);
316 static int machine__write_buildid_table(struct machine *machine,
321 u16 kmisc = PERF_RECORD_MISC_KERNEL,
322 umisc = PERF_RECORD_MISC_USER;
324 if (!machine__is_host(machine)) {
325 kmisc = PERF_RECORD_MISC_GUEST_KERNEL;
326 umisc = PERF_RECORD_MISC_GUEST_USER;
329 dsos__for_each_with_build_id(pos, &machine->dsos.head) {
332 bool in_kernel = false;
334 if (!pos->hit && !dso__is_vdso(pos))
337 if (dso__is_vdso(pos)) {
338 name = pos->short_name;
339 name_len = pos->short_name_len;
340 } else if (dso__is_kcore(pos)) {
341 name = machine->mmap_name;
342 name_len = strlen(name);
344 name = pos->long_name;
345 name_len = pos->long_name_len;
348 in_kernel = pos->kernel ||
349 is_kernel_module(name,
350 PERF_RECORD_MISC_CPUMODE_UNKNOWN);
351 err = write_buildid(name, name_len, pos->build_id, machine->pid,
352 in_kernel ? kmisc : umisc, fd);
360 int perf_session__write_buildid_table(struct perf_session *session,
364 int err = machine__write_buildid_table(&session->machines.host, fd);
369 for (nd = rb_first_cached(&session->machines.guests); nd;
371 struct machine *pos = rb_entry(nd, struct machine, rb_node);
372 err = machine__write_buildid_table(pos, fd);
379 static int __dsos__hit_all(struct list_head *head)
383 list_for_each_entry(pos, head, node)
389 static int machine__hit_all_dsos(struct machine *machine)
391 return __dsos__hit_all(&machine->dsos.head);
394 int dsos__hit_all(struct perf_session *session)
399 err = machine__hit_all_dsos(&session->machines.host);
403 for (nd = rb_first_cached(&session->machines.guests); nd;
405 struct machine *pos = rb_entry(nd, struct machine, rb_node);
407 err = machine__hit_all_dsos(pos);
415 void disable_buildid_cache(void)
417 no_buildid_cache = true;
420 static bool lsdir_bid_head_filter(const char *name __maybe_unused,
423 return (strlen(d->d_name) == 2) &&
424 isxdigit(d->d_name[0]) && isxdigit(d->d_name[1]);
427 static bool lsdir_bid_tail_filter(const char *name __maybe_unused,
431 while (isxdigit(d->d_name[i]) && i < SBUILD_ID_SIZE - 3)
433 return (i == SBUILD_ID_SIZE - 3) && (d->d_name[i] == '\0');
436 struct strlist *build_id_cache__list_all(bool validonly)
438 struct strlist *toplist, *linklist = NULL, *bidlist;
439 struct str_node *nd, *nd2;
440 char *topdir, *linkdir = NULL;
441 char sbuild_id[SBUILD_ID_SIZE];
443 /* for filename__ functions */
447 /* Open the top-level directory */
448 if (asprintf(&topdir, "%s/.build-id/", buildid_dir) < 0)
451 bidlist = strlist__new(NULL, NULL);
455 toplist = lsdir(topdir, lsdir_bid_head_filter);
457 pr_debug("Error in lsdir(%s): %d\n", topdir, errno);
458 /* If there is no buildid cache, return an empty list */
464 strlist__for_each_entry(nd, toplist) {
465 if (asprintf(&linkdir, "%s/%s", topdir, nd->s) < 0)
467 /* Open the lower-level directory */
468 linklist = lsdir(linkdir, lsdir_bid_tail_filter);
470 pr_debug("Error in lsdir(%s): %d\n", linkdir, errno);
473 strlist__for_each_entry(nd2, linklist) {
474 if (snprintf(sbuild_id, SBUILD_ID_SIZE, "%s%s",
475 nd->s, nd2->s) != SBUILD_ID_SIZE - 1)
477 if (validonly && !build_id_cache__valid_id(sbuild_id))
479 if (strlist__add(bidlist, sbuild_id) < 0)
482 strlist__delete(linklist);
487 strlist__delete(toplist);
494 strlist__delete(linklist);
496 strlist__delete(bidlist);
501 static bool str_is_build_id(const char *maybe_sbuild_id, size_t len)
505 for (i = 0; i < len; i++) {
506 if (!isxdigit(maybe_sbuild_id[i]))
512 /* Return the valid complete build-id */
513 char *build_id_cache__complement(const char *incomplete_sbuild_id)
515 struct strlist *bidlist;
516 struct str_node *nd, *cand = NULL;
517 char *sbuild_id = NULL;
518 size_t len = strlen(incomplete_sbuild_id);
520 if (len >= SBUILD_ID_SIZE ||
521 !str_is_build_id(incomplete_sbuild_id, len))
524 bidlist = build_id_cache__list_all(true);
528 strlist__for_each_entry(nd, bidlist) {
529 if (strncmp(nd->s, incomplete_sbuild_id, len) != 0)
531 if (cand) { /* Error: There are more than 2 candidates. */
538 sbuild_id = strdup(cand->s);
539 strlist__delete(bidlist);
544 char *build_id_cache__cachedir(const char *sbuild_id, const char *name,
545 struct nsinfo *nsi, bool is_kallsyms,
548 char *realname = (char *)name, *filename;
549 bool slash = is_kallsyms || is_vdso;
552 realname = nsinfo__realpath(name, nsi);
557 if (asprintf(&filename, "%s%s%s%s%s", buildid_dir, slash ? "/" : "",
558 is_vdso ? DSO__NAME_VDSO : realname,
559 sbuild_id ? "/" : "", sbuild_id ?: "") < 0)
568 int build_id_cache__list_build_ids(const char *pathname, struct nsinfo *nsi,
569 struct strlist **result)
574 dir_name = build_id_cache__cachedir(NULL, pathname, nsi, false, false);
578 *result = lsdir(dir_name, lsdir_no_dot_filter);
586 #if defined(HAVE_LIBELF_SUPPORT) && defined(HAVE_GELF_GETNOTE_SUPPORT)
587 static int build_id_cache__add_sdt_cache(const char *sbuild_id,
588 const char *realname,
591 struct probe_cache *cache;
595 cache = probe_cache__new(sbuild_id, nsi);
599 nsinfo__mountns_enter(nsi, &nsc);
600 ret = probe_cache__scan_sdt(cache, realname);
601 nsinfo__mountns_exit(&nsc);
603 pr_debug4("Found %d SDTs in %s\n", ret, realname);
604 if (probe_cache__commit(cache) < 0)
607 probe_cache__delete(cache);
611 #define build_id_cache__add_sdt_cache(sbuild_id, realname, nsi) (0)
614 static char *build_id_cache__find_debug(const char *sbuild_id,
617 char *realname = NULL;
622 debugfile = calloc(1, PATH_MAX);
626 len = __symbol__join_symfs(debugfile, PATH_MAX,
627 "/usr/lib/debug/.build-id/");
628 snprintf(debugfile + len, PATH_MAX - len, "%.2s/%s.debug", sbuild_id,
631 nsinfo__mountns_enter(nsi, &nsc);
632 realname = realpath(debugfile, NULL);
633 if (realname && access(realname, R_OK))
635 nsinfo__mountns_exit(&nsc);
641 int build_id_cache__add_s(const char *sbuild_id, const char *name,
642 struct nsinfo *nsi, bool is_kallsyms, bool is_vdso)
644 const size_t size = PATH_MAX;
645 char *realname = NULL, *filename = NULL, *dir_name = NULL,
646 *linkname = zalloc(size), *tmp;
647 char *debugfile = NULL;
652 realname = nsinfo__realpath(name, nsi);
654 realname = realpath(name, NULL);
659 dir_name = build_id_cache__cachedir(sbuild_id, name, nsi, is_kallsyms,
664 /* Remove old style build-id cache */
665 if (is_regular_file(dir_name))
666 if (unlink(dir_name))
669 if (mkdir_p(dir_name, 0755))
672 /* Save the allocated buildid dirname */
673 if (asprintf(&filename, "%s/%s", dir_name,
674 build_id_cache__basename(is_kallsyms, is_vdso,
680 if (access(filename, F_OK)) {
682 if (copyfile("/proc/kallsyms", filename))
684 } else if (nsi && nsi->need_setns) {
685 if (copyfile_ns(name, filename, nsi))
687 } else if (link(realname, filename) && errno != EEXIST &&
688 copyfile(name, filename))
692 /* Some binaries are stripped, but have .debug files with their symbol
693 * table. Check to see if we can locate one of those, since the elf
694 * file itself may not be very useful to users of our tools without a
697 if (!is_kallsyms && !is_vdso &&
698 strncmp(".ko", name + strlen(name) - 3, 3)) {
699 debugfile = build_id_cache__find_debug(sbuild_id, nsi);
702 if (asprintf(&filename, "%s/%s", dir_name,
703 build_id_cache__basename(false, false, true)) < 0) {
707 if (access(filename, F_OK)) {
708 if (nsi && nsi->need_setns) {
709 if (copyfile_ns(debugfile, filename,
712 } else if (link(debugfile, filename) &&
714 copyfile(debugfile, filename))
720 if (!build_id_cache__linkname(sbuild_id, linkname, size))
722 tmp = strrchr(linkname, '/');
725 if (access(linkname, X_OK) && mkdir_p(linkname, 0755))
729 tmp = dir_name + strlen(buildid_dir) - 5;
730 memcpy(tmp, "../..", 5);
732 if (symlink(tmp, linkname) == 0)
735 /* Update SDT cache : error is just warned */
737 build_id_cache__add_sdt_cache(sbuild_id, realname, nsi) < 0)
738 pr_debug4("Failed to update/scan SDT cache for %s\n", realname);
750 static int build_id_cache__add_b(const u8 *build_id, size_t build_id_size,
751 const char *name, struct nsinfo *nsi,
752 bool is_kallsyms, bool is_vdso)
754 char sbuild_id[SBUILD_ID_SIZE];
756 build_id__sprintf(build_id, build_id_size, sbuild_id);
758 return build_id_cache__add_s(sbuild_id, name, nsi, is_kallsyms,
762 bool build_id_cache__cached(const char *sbuild_id)
765 char *filename = build_id_cache__linkname(sbuild_id, NULL, 0);
767 if (filename && !access(filename, F_OK))
774 int build_id_cache__remove_s(const char *sbuild_id)
776 const size_t size = PATH_MAX;
777 char *filename = zalloc(size),
778 *linkname = zalloc(size), *tmp;
781 if (filename == NULL || linkname == NULL)
784 if (!build_id_cache__linkname(sbuild_id, linkname, size))
787 if (access(linkname, F_OK))
790 if (readlink(linkname, filename, size - 1) < 0)
793 if (unlink(linkname))
797 * Since the link is relative, we must make it absolute:
799 tmp = strrchr(linkname, '/') + 1;
800 snprintf(tmp, size - (tmp - linkname), "%s", filename);
812 static int dso__cache_build_id(struct dso *dso, struct machine *machine)
814 bool is_kallsyms = dso__is_kallsyms(dso);
815 bool is_vdso = dso__is_vdso(dso);
816 const char *name = dso->long_name;
818 if (dso__is_kcore(dso)) {
820 name = machine->mmap_name;
822 return build_id_cache__add_b(dso->build_id, sizeof(dso->build_id), name,
823 dso->nsinfo, is_kallsyms, is_vdso);
826 static int __dsos__cache_build_ids(struct list_head *head,
827 struct machine *machine)
832 dsos__for_each_with_build_id(pos, head)
833 if (dso__cache_build_id(pos, machine))
839 static int machine__cache_build_ids(struct machine *machine)
841 return __dsos__cache_build_ids(&machine->dsos.head, machine);
844 int perf_session__cache_build_ids(struct perf_session *session)
849 if (no_buildid_cache)
852 if (mkdir(buildid_dir, 0755) != 0 && errno != EEXIST)
855 ret = machine__cache_build_ids(&session->machines.host);
857 for (nd = rb_first_cached(&session->machines.guests); nd;
859 struct machine *pos = rb_entry(nd, struct machine, rb_node);
860 ret |= machine__cache_build_ids(pos);
865 static bool machine__read_build_ids(struct machine *machine, bool with_hits)
867 return __dsos__read_build_ids(&machine->dsos.head, with_hits);
870 bool perf_session__read_build_ids(struct perf_session *session, bool with_hits)
873 bool ret = machine__read_build_ids(&session->machines.host, with_hits);
875 for (nd = rb_first_cached(&session->machines.guests); nd;
877 struct machine *pos = rb_entry(nd, struct machine, rb_node);
878 ret |= machine__read_build_ids(pos, with_hits);