v4.19.13 snapshot.
diff --git a/tools/perf/util/build-id.c b/tools/perf/util/build-id.c
new file mode 100644
index 0000000..04b1d53
--- /dev/null
+++ b/tools/perf/util/build-id.c
@@ -0,0 +1,875 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * build-id.c
+ *
+ * build-id support
+ *
+ * Copyright (C) 2009, 2010 Red Hat Inc.
+ * Copyright (C) 2009, 2010 Arnaldo Carvalho de Melo <acme@redhat.com>
+ */
+#include "util.h"
+#include <dirent.h>
+#include <errno.h>
+#include <stdio.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include "build-id.h"
+#include "event.h"
+#include "symbol.h"
+#include "thread.h"
+#include <linux/kernel.h>
+#include "debug.h"
+#include "session.h"
+#include "tool.h"
+#include "header.h"
+#include "vdso.h"
+#include "path.h"
+#include "probe-file.h"
+#include "strlist.h"
+
+#include "sane_ctype.h"
+
+static bool no_buildid_cache;
+
+int build_id__mark_dso_hit(struct perf_tool *tool __maybe_unused,
+ union perf_event *event,
+ struct perf_sample *sample,
+ struct perf_evsel *evsel __maybe_unused,
+ struct machine *machine)
+{
+ struct addr_location al;
+ struct thread *thread = machine__findnew_thread(machine, sample->pid,
+ sample->tid);
+
+ if (thread == NULL) {
+ pr_err("problem processing %d event, skipping it.\n",
+ event->header.type);
+ return -1;
+ }
+
+ if (thread__find_map(thread, sample->cpumode, sample->ip, &al))
+ al.map->dso->hit = 1;
+
+ thread__put(thread);
+ return 0;
+}
+
+static int perf_event__exit_del_thread(struct perf_tool *tool __maybe_unused,
+ union perf_event *event,
+ struct perf_sample *sample
+ __maybe_unused,
+ struct machine *machine)
+{
+ struct thread *thread = machine__findnew_thread(machine,
+ event->fork.pid,
+ event->fork.tid);
+
+ dump_printf("(%d:%d):(%d:%d)\n", event->fork.pid, event->fork.tid,
+ event->fork.ppid, event->fork.ptid);
+
+ if (thread) {
+ machine__remove_thread(machine, thread);
+ thread__put(thread);
+ }
+
+ return 0;
+}
+
+struct perf_tool build_id__mark_dso_hit_ops = {
+ .sample = build_id__mark_dso_hit,
+ .mmap = perf_event__process_mmap,
+ .mmap2 = perf_event__process_mmap2,
+ .fork = perf_event__process_fork,
+ .exit = perf_event__exit_del_thread,
+ .attr = perf_event__process_attr,
+ .build_id = perf_event__process_build_id,
+ .ordered_events = true,
+};
+
+int build_id__sprintf(const u8 *build_id, int len, char *bf)
+{
+ char *bid = bf;
+ const u8 *raw = build_id;
+ int i;
+
+ for (i = 0; i < len; ++i) {
+ sprintf(bid, "%02x", *raw);
+ ++raw;
+ bid += 2;
+ }
+
+ return (bid - bf) + 1;
+}
+
+int sysfs__sprintf_build_id(const char *root_dir, char *sbuild_id)
+{
+ char notes[PATH_MAX];
+ u8 build_id[BUILD_ID_SIZE];
+ int ret;
+
+ if (!root_dir)
+ root_dir = "";
+
+ scnprintf(notes, sizeof(notes), "%s/sys/kernel/notes", root_dir);
+
+ ret = sysfs__read_build_id(notes, build_id, sizeof(build_id));
+ if (ret < 0)
+ return ret;
+
+ return build_id__sprintf(build_id, sizeof(build_id), sbuild_id);
+}
+
+int filename__sprintf_build_id(const char *pathname, char *sbuild_id)
+{
+ u8 build_id[BUILD_ID_SIZE];
+ int ret;
+
+ ret = filename__read_build_id(pathname, build_id, sizeof(build_id));
+ if (ret < 0)
+ return ret;
+ else if (ret != sizeof(build_id))
+ return -EINVAL;
+
+ return build_id__sprintf(build_id, sizeof(build_id), sbuild_id);
+}
+
+/* asnprintf consolidates asprintf and snprintf */
+static int asnprintf(char **strp, size_t size, const char *fmt, ...)
+{
+ va_list ap;
+ int ret;
+
+ if (!strp)
+ return -EINVAL;
+
+ va_start(ap, fmt);
+ if (*strp)
+ ret = vsnprintf(*strp, size, fmt, ap);
+ else
+ ret = vasprintf(strp, fmt, ap);
+ va_end(ap);
+
+ return ret;
+}
+
+char *build_id_cache__kallsyms_path(const char *sbuild_id, char *bf,
+ size_t size)
+{
+ bool retry_old = true;
+
+ snprintf(bf, size, "%s/%s/%s/kallsyms",
+ buildid_dir, DSO__NAME_KALLSYMS, sbuild_id);
+retry:
+ if (!access(bf, F_OK))
+ return bf;
+ if (retry_old) {
+ /* Try old style kallsyms cache */
+ snprintf(bf, size, "%s/%s/%s",
+ buildid_dir, DSO__NAME_KALLSYMS, sbuild_id);
+ retry_old = false;
+ goto retry;
+ }
+
+ return NULL;
+}
+
+char *build_id_cache__linkname(const char *sbuild_id, char *bf, size_t size)
+{
+ char *tmp = bf;
+ int ret = asnprintf(&bf, size, "%s/.build-id/%.2s/%s", buildid_dir,
+ sbuild_id, sbuild_id + 2);
+ if (ret < 0 || (tmp && size < (unsigned int)ret))
+ return NULL;
+ return bf;
+}
+
+char *build_id_cache__origname(const char *sbuild_id)
+{
+ char *linkname;
+ char buf[PATH_MAX];
+ char *ret = NULL, *p;
+ size_t offs = 5; /* == strlen("../..") */
+ ssize_t len;
+
+ linkname = build_id_cache__linkname(sbuild_id, NULL, 0);
+ if (!linkname)
+ return NULL;
+
+ len = readlink(linkname, buf, sizeof(buf) - 1);
+ if (len <= 0)
+ goto out;
+ buf[len] = '\0';
+
+ /* The link should be "../..<origpath>/<sbuild_id>" */
+ p = strrchr(buf, '/'); /* Cut off the "/<sbuild_id>" */
+ if (p && (p > buf + offs)) {
+ *p = '\0';
+ if (buf[offs + 1] == '[')
+ offs++; /*
+ * This is a DSO name, like [kernel.kallsyms].
+ * Skip the first '/', since this is not the
+ * cache of a regular file.
+ */
+ ret = strdup(buf + offs); /* Skip "../..[/]" */
+ }
+out:
+ free(linkname);
+ return ret;
+}
+
+/* Check if the given build_id cache is valid on current running system */
+static bool build_id_cache__valid_id(char *sbuild_id)
+{
+ char real_sbuild_id[SBUILD_ID_SIZE] = "";
+ char *pathname;
+ int ret = 0;
+ bool result = false;
+
+ pathname = build_id_cache__origname(sbuild_id);
+ if (!pathname)
+ return false;
+
+ if (!strcmp(pathname, DSO__NAME_KALLSYMS))
+ ret = sysfs__sprintf_build_id("/", real_sbuild_id);
+ else if (pathname[0] == '/')
+ ret = filename__sprintf_build_id(pathname, real_sbuild_id);
+ else
+ ret = -EINVAL; /* Should we support other special DSO cache? */
+ if (ret >= 0)
+ result = (strcmp(sbuild_id, real_sbuild_id) == 0);
+ free(pathname);
+
+ return result;
+}
+
+static const char *build_id_cache__basename(bool is_kallsyms, bool is_vdso,
+ bool is_debug)
+{
+ return is_kallsyms ? "kallsyms" : (is_vdso ? "vdso" : (is_debug ?
+ "debug" : "elf"));
+}
+
+char *dso__build_id_filename(const struct dso *dso, char *bf, size_t size,
+ bool is_debug)
+{
+ bool is_kallsyms = dso__is_kallsyms((struct dso *)dso);
+ bool is_vdso = dso__is_vdso((struct dso *)dso);
+ char sbuild_id[SBUILD_ID_SIZE];
+ char *linkname;
+ bool alloc = (bf == NULL);
+ int ret;
+
+ if (!dso->has_build_id)
+ return NULL;
+
+ build_id__sprintf(dso->build_id, sizeof(dso->build_id), sbuild_id);
+ linkname = build_id_cache__linkname(sbuild_id, NULL, 0);
+ if (!linkname)
+ return NULL;
+
+ /* Check if old style build_id cache */
+ if (is_regular_file(linkname))
+ ret = asnprintf(&bf, size, "%s", linkname);
+ else
+ ret = asnprintf(&bf, size, "%s/%s", linkname,
+ build_id_cache__basename(is_kallsyms, is_vdso,
+ is_debug));
+ if (ret < 0 || (!alloc && size < (unsigned int)ret))
+ bf = NULL;
+ free(linkname);
+
+ return bf;
+}
+
+#define dsos__for_each_with_build_id(pos, head) \
+ list_for_each_entry(pos, head, node) \
+ if (!pos->has_build_id) \
+ continue; \
+ else
+
+static int write_buildid(const char *name, size_t name_len, u8 *build_id,
+ pid_t pid, u16 misc, struct feat_fd *fd)
+{
+ int err;
+ struct build_id_event b;
+ size_t len;
+
+ len = name_len + 1;
+ len = PERF_ALIGN(len, NAME_ALIGN);
+
+ memset(&b, 0, sizeof(b));
+ memcpy(&b.build_id, build_id, BUILD_ID_SIZE);
+ b.pid = pid;
+ b.header.misc = misc;
+ b.header.size = sizeof(b) + len;
+
+ err = do_write(fd, &b, sizeof(b));
+ if (err < 0)
+ return err;
+
+ return write_padded(fd, name, name_len + 1, len);
+}
+
+static int machine__write_buildid_table(struct machine *machine,
+ struct feat_fd *fd)
+{
+ int err = 0;
+ struct dso *pos;
+ u16 kmisc = PERF_RECORD_MISC_KERNEL,
+ umisc = PERF_RECORD_MISC_USER;
+
+ if (!machine__is_host(machine)) {
+ kmisc = PERF_RECORD_MISC_GUEST_KERNEL;
+ umisc = PERF_RECORD_MISC_GUEST_USER;
+ }
+
+ dsos__for_each_with_build_id(pos, &machine->dsos.head) {
+ const char *name;
+ size_t name_len;
+ bool in_kernel = false;
+
+ if (!pos->hit && !dso__is_vdso(pos))
+ continue;
+
+ if (dso__is_vdso(pos)) {
+ name = pos->short_name;
+ name_len = pos->short_name_len;
+ } else if (dso__is_kcore(pos)) {
+ name = machine->mmap_name;
+ name_len = strlen(name);
+ } else {
+ name = pos->long_name;
+ name_len = pos->long_name_len;
+ }
+
+ in_kernel = pos->kernel ||
+ is_kernel_module(name,
+ PERF_RECORD_MISC_CPUMODE_UNKNOWN);
+ err = write_buildid(name, name_len, pos->build_id, machine->pid,
+ in_kernel ? kmisc : umisc, fd);
+ if (err)
+ break;
+ }
+
+ return err;
+}
+
+int perf_session__write_buildid_table(struct perf_session *session,
+ struct feat_fd *fd)
+{
+ struct rb_node *nd;
+ int err = machine__write_buildid_table(&session->machines.host, fd);
+
+ if (err)
+ return err;
+
+ for (nd = rb_first(&session->machines.guests); nd; nd = rb_next(nd)) {
+ struct machine *pos = rb_entry(nd, struct machine, rb_node);
+ err = machine__write_buildid_table(pos, fd);
+ if (err)
+ break;
+ }
+ return err;
+}
+
+static int __dsos__hit_all(struct list_head *head)
+{
+ struct dso *pos;
+
+ list_for_each_entry(pos, head, node)
+ pos->hit = true;
+
+ return 0;
+}
+
+static int machine__hit_all_dsos(struct machine *machine)
+{
+ return __dsos__hit_all(&machine->dsos.head);
+}
+
+int dsos__hit_all(struct perf_session *session)
+{
+ struct rb_node *nd;
+ int err;
+
+ err = machine__hit_all_dsos(&session->machines.host);
+ if (err)
+ return err;
+
+ for (nd = rb_first(&session->machines.guests); nd; nd = rb_next(nd)) {
+ struct machine *pos = rb_entry(nd, struct machine, rb_node);
+
+ err = machine__hit_all_dsos(pos);
+ if (err)
+ return err;
+ }
+
+ return 0;
+}
+
+void disable_buildid_cache(void)
+{
+ no_buildid_cache = true;
+}
+
+static bool lsdir_bid_head_filter(const char *name __maybe_unused,
+ struct dirent *d)
+{
+ return (strlen(d->d_name) == 2) &&
+ isxdigit(d->d_name[0]) && isxdigit(d->d_name[1]);
+}
+
+static bool lsdir_bid_tail_filter(const char *name __maybe_unused,
+ struct dirent *d)
+{
+ int i = 0;
+ while (isxdigit(d->d_name[i]) && i < SBUILD_ID_SIZE - 3)
+ i++;
+ return (i == SBUILD_ID_SIZE - 3) && (d->d_name[i] == '\0');
+}
+
+struct strlist *build_id_cache__list_all(bool validonly)
+{
+ struct strlist *toplist, *linklist = NULL, *bidlist;
+ struct str_node *nd, *nd2;
+ char *topdir, *linkdir = NULL;
+ char sbuild_id[SBUILD_ID_SIZE];
+
+ /* for filename__ functions */
+ if (validonly)
+ symbol__init(NULL);
+
+ /* Open the top-level directory */
+ if (asprintf(&topdir, "%s/.build-id/", buildid_dir) < 0)
+ return NULL;
+
+ bidlist = strlist__new(NULL, NULL);
+ if (!bidlist)
+ goto out;
+
+ toplist = lsdir(topdir, lsdir_bid_head_filter);
+ if (!toplist) {
+ pr_debug("Error in lsdir(%s): %d\n", topdir, errno);
+ /* If there is no buildid cache, return an empty list */
+ if (errno == ENOENT)
+ goto out;
+ goto err_out;
+ }
+
+ strlist__for_each_entry(nd, toplist) {
+ if (asprintf(&linkdir, "%s/%s", topdir, nd->s) < 0)
+ goto err_out;
+ /* Open the lower-level directory */
+ linklist = lsdir(linkdir, lsdir_bid_tail_filter);
+ if (!linklist) {
+ pr_debug("Error in lsdir(%s): %d\n", linkdir, errno);
+ goto err_out;
+ }
+ strlist__for_each_entry(nd2, linklist) {
+ if (snprintf(sbuild_id, SBUILD_ID_SIZE, "%s%s",
+ nd->s, nd2->s) != SBUILD_ID_SIZE - 1)
+ goto err_out;
+ if (validonly && !build_id_cache__valid_id(sbuild_id))
+ continue;
+ if (strlist__add(bidlist, sbuild_id) < 0)
+ goto err_out;
+ }
+ strlist__delete(linklist);
+ zfree(&linkdir);
+ }
+
+out_free:
+ strlist__delete(toplist);
+out:
+ free(topdir);
+
+ return bidlist;
+
+err_out:
+ strlist__delete(linklist);
+ zfree(&linkdir);
+ strlist__delete(bidlist);
+ bidlist = NULL;
+ goto out_free;
+}
+
+static bool str_is_build_id(const char *maybe_sbuild_id, size_t len)
+{
+ size_t i;
+
+ for (i = 0; i < len; i++) {
+ if (!isxdigit(maybe_sbuild_id[i]))
+ return false;
+ }
+ return true;
+}
+
+/* Return the valid complete build-id */
+char *build_id_cache__complement(const char *incomplete_sbuild_id)
+{
+ struct strlist *bidlist;
+ struct str_node *nd, *cand = NULL;
+ char *sbuild_id = NULL;
+ size_t len = strlen(incomplete_sbuild_id);
+
+ if (len >= SBUILD_ID_SIZE ||
+ !str_is_build_id(incomplete_sbuild_id, len))
+ return NULL;
+
+ bidlist = build_id_cache__list_all(true);
+ if (!bidlist)
+ return NULL;
+
+ strlist__for_each_entry(nd, bidlist) {
+ if (strncmp(nd->s, incomplete_sbuild_id, len) != 0)
+ continue;
+ if (cand) { /* Error: There are more than 2 candidates. */
+ cand = NULL;
+ break;
+ }
+ cand = nd;
+ }
+ if (cand)
+ sbuild_id = strdup(cand->s);
+ strlist__delete(bidlist);
+
+ return sbuild_id;
+}
+
+char *build_id_cache__cachedir(const char *sbuild_id, const char *name,
+ struct nsinfo *nsi, bool is_kallsyms,
+ bool is_vdso)
+{
+ char *realname = (char *)name, *filename;
+ bool slash = is_kallsyms || is_vdso;
+
+ if (!slash) {
+ realname = nsinfo__realpath(name, nsi);
+ if (!realname)
+ return NULL;
+ }
+
+ if (asprintf(&filename, "%s%s%s%s%s", buildid_dir, slash ? "/" : "",
+ is_vdso ? DSO__NAME_VDSO : realname,
+ sbuild_id ? "/" : "", sbuild_id ?: "") < 0)
+ filename = NULL;
+
+ if (!slash)
+ free(realname);
+
+ return filename;
+}
+
+int build_id_cache__list_build_ids(const char *pathname, struct nsinfo *nsi,
+ struct strlist **result)
+{
+ char *dir_name;
+ int ret = 0;
+
+ dir_name = build_id_cache__cachedir(NULL, pathname, nsi, false, false);
+ if (!dir_name)
+ return -ENOMEM;
+
+ *result = lsdir(dir_name, lsdir_no_dot_filter);
+ if (!*result)
+ ret = -errno;
+ free(dir_name);
+
+ return ret;
+}
+
+#if defined(HAVE_LIBELF_SUPPORT) && defined(HAVE_GELF_GETNOTE_SUPPORT)
+static int build_id_cache__add_sdt_cache(const char *sbuild_id,
+ const char *realname,
+ struct nsinfo *nsi)
+{
+ struct probe_cache *cache;
+ int ret;
+ struct nscookie nsc;
+
+ cache = probe_cache__new(sbuild_id, nsi);
+ if (!cache)
+ return -1;
+
+ nsinfo__mountns_enter(nsi, &nsc);
+ ret = probe_cache__scan_sdt(cache, realname);
+ nsinfo__mountns_exit(&nsc);
+ if (ret >= 0) {
+ pr_debug4("Found %d SDTs in %s\n", ret, realname);
+ if (probe_cache__commit(cache) < 0)
+ ret = -1;
+ }
+ probe_cache__delete(cache);
+ return ret;
+}
+#else
+#define build_id_cache__add_sdt_cache(sbuild_id, realname, nsi) (0)
+#endif
+
+static char *build_id_cache__find_debug(const char *sbuild_id,
+ struct nsinfo *nsi)
+{
+ char *realname = NULL;
+ char *debugfile;
+ struct nscookie nsc;
+ size_t len = 0;
+
+ debugfile = calloc(1, PATH_MAX);
+ if (!debugfile)
+ goto out;
+
+ len = __symbol__join_symfs(debugfile, PATH_MAX,
+ "/usr/lib/debug/.build-id/");
+ snprintf(debugfile + len, PATH_MAX - len, "%.2s/%s.debug", sbuild_id,
+ sbuild_id + 2);
+
+ nsinfo__mountns_enter(nsi, &nsc);
+ realname = realpath(debugfile, NULL);
+ if (realname && access(realname, R_OK))
+ zfree(&realname);
+ nsinfo__mountns_exit(&nsc);
+out:
+ free(debugfile);
+ return realname;
+}
+
+int build_id_cache__add_s(const char *sbuild_id, const char *name,
+ struct nsinfo *nsi, bool is_kallsyms, bool is_vdso)
+{
+ const size_t size = PATH_MAX;
+ char *realname = NULL, *filename = NULL, *dir_name = NULL,
+ *linkname = zalloc(size), *tmp;
+ char *debugfile = NULL;
+ int err = -1;
+
+ if (!is_kallsyms) {
+ if (!is_vdso)
+ realname = nsinfo__realpath(name, nsi);
+ else
+ realname = realpath(name, NULL);
+ if (!realname)
+ goto out_free;
+ }
+
+ dir_name = build_id_cache__cachedir(sbuild_id, name, nsi, is_kallsyms,
+ is_vdso);
+ if (!dir_name)
+ goto out_free;
+
+ /* Remove old style build-id cache */
+ if (is_regular_file(dir_name))
+ if (unlink(dir_name))
+ goto out_free;
+
+ if (mkdir_p(dir_name, 0755))
+ goto out_free;
+
+ /* Save the allocated buildid dirname */
+ if (asprintf(&filename, "%s/%s", dir_name,
+ build_id_cache__basename(is_kallsyms, is_vdso,
+ false)) < 0) {
+ filename = NULL;
+ goto out_free;
+ }
+
+ if (access(filename, F_OK)) {
+ if (is_kallsyms) {
+ if (copyfile("/proc/kallsyms", filename))
+ goto out_free;
+ } else if (nsi && nsi->need_setns) {
+ if (copyfile_ns(name, filename, nsi))
+ goto out_free;
+ } else if (link(realname, filename) && errno != EEXIST &&
+ copyfile(name, filename))
+ goto out_free;
+ }
+
+ /* Some binaries are stripped, but have .debug files with their symbol
+ * table. Check to see if we can locate one of those, since the elf
+ * file itself may not be very useful to users of our tools without a
+ * symtab.
+ */
+ if (!is_kallsyms && !is_vdso &&
+ strncmp(".ko", name + strlen(name) - 3, 3)) {
+ debugfile = build_id_cache__find_debug(sbuild_id, nsi);
+ if (debugfile) {
+ zfree(&filename);
+ if (asprintf(&filename, "%s/%s", dir_name,
+ build_id_cache__basename(false, false, true)) < 0) {
+ filename = NULL;
+ goto out_free;
+ }
+ if (access(filename, F_OK)) {
+ if (nsi && nsi->need_setns) {
+ if (copyfile_ns(debugfile, filename,
+ nsi))
+ goto out_free;
+ } else if (link(debugfile, filename) &&
+ errno != EEXIST &&
+ copyfile(debugfile, filename))
+ goto out_free;
+ }
+ }
+ }
+
+ if (!build_id_cache__linkname(sbuild_id, linkname, size))
+ goto out_free;
+ tmp = strrchr(linkname, '/');
+ *tmp = '\0';
+
+ if (access(linkname, X_OK) && mkdir_p(linkname, 0755))
+ goto out_free;
+
+ *tmp = '/';
+ tmp = dir_name + strlen(buildid_dir) - 5;
+ memcpy(tmp, "../..", 5);
+
+ if (symlink(tmp, linkname) == 0)
+ err = 0;
+
+ /* Update SDT cache : error is just warned */
+ if (realname &&
+ build_id_cache__add_sdt_cache(sbuild_id, realname, nsi) < 0)
+ pr_debug4("Failed to update/scan SDT cache for %s\n", realname);
+
+out_free:
+ if (!is_kallsyms)
+ free(realname);
+ free(filename);
+ free(debugfile);
+ free(dir_name);
+ free(linkname);
+ return err;
+}
+
+static int build_id_cache__add_b(const u8 *build_id, size_t build_id_size,
+ const char *name, struct nsinfo *nsi,
+ bool is_kallsyms, bool is_vdso)
+{
+ char sbuild_id[SBUILD_ID_SIZE];
+
+ build_id__sprintf(build_id, build_id_size, sbuild_id);
+
+ return build_id_cache__add_s(sbuild_id, name, nsi, is_kallsyms,
+ is_vdso);
+}
+
+bool build_id_cache__cached(const char *sbuild_id)
+{
+ bool ret = false;
+ char *filename = build_id_cache__linkname(sbuild_id, NULL, 0);
+
+ if (filename && !access(filename, F_OK))
+ ret = true;
+ free(filename);
+
+ return ret;
+}
+
+int build_id_cache__remove_s(const char *sbuild_id)
+{
+ const size_t size = PATH_MAX;
+ char *filename = zalloc(size),
+ *linkname = zalloc(size), *tmp;
+ int err = -1;
+
+ if (filename == NULL || linkname == NULL)
+ goto out_free;
+
+ if (!build_id_cache__linkname(sbuild_id, linkname, size))
+ goto out_free;
+
+ if (access(linkname, F_OK))
+ goto out_free;
+
+ if (readlink(linkname, filename, size - 1) < 0)
+ goto out_free;
+
+ if (unlink(linkname))
+ goto out_free;
+
+ /*
+ * Since the link is relative, we must make it absolute:
+ */
+ tmp = strrchr(linkname, '/') + 1;
+ snprintf(tmp, size - (tmp - linkname), "%s", filename);
+
+ if (rm_rf(linkname))
+ goto out_free;
+
+ err = 0;
+out_free:
+ free(filename);
+ free(linkname);
+ return err;
+}
+
+static int dso__cache_build_id(struct dso *dso, struct machine *machine)
+{
+ bool is_kallsyms = dso__is_kallsyms(dso);
+ bool is_vdso = dso__is_vdso(dso);
+ const char *name = dso->long_name;
+
+ if (dso__is_kcore(dso)) {
+ is_kallsyms = true;
+ name = machine->mmap_name;
+ }
+ return build_id_cache__add_b(dso->build_id, sizeof(dso->build_id), name,
+ dso->nsinfo, is_kallsyms, is_vdso);
+}
+
+static int __dsos__cache_build_ids(struct list_head *head,
+ struct machine *machine)
+{
+ struct dso *pos;
+ int err = 0;
+
+ dsos__for_each_with_build_id(pos, head)
+ if (dso__cache_build_id(pos, machine))
+ err = -1;
+
+ return err;
+}
+
+static int machine__cache_build_ids(struct machine *machine)
+{
+ return __dsos__cache_build_ids(&machine->dsos.head, machine);
+}
+
+int perf_session__cache_build_ids(struct perf_session *session)
+{
+ struct rb_node *nd;
+ int ret;
+
+ if (no_buildid_cache)
+ return 0;
+
+ if (mkdir(buildid_dir, 0755) != 0 && errno != EEXIST)
+ return -1;
+
+ ret = machine__cache_build_ids(&session->machines.host);
+
+ for (nd = rb_first(&session->machines.guests); nd; nd = rb_next(nd)) {
+ struct machine *pos = rb_entry(nd, struct machine, rb_node);
+ ret |= machine__cache_build_ids(pos);
+ }
+ return ret ? -1 : 0;
+}
+
+static bool machine__read_build_ids(struct machine *machine, bool with_hits)
+{
+ return __dsos__read_build_ids(&machine->dsos.head, with_hits);
+}
+
+bool perf_session__read_build_ids(struct perf_session *session, bool with_hits)
+{
+ struct rb_node *nd;
+ bool ret = machine__read_build_ids(&session->machines.host, with_hits);
+
+ for (nd = rb_first(&session->machines.guests); nd; nd = rb_next(nd)) {
+ struct machine *pos = rb_entry(nd, struct machine, rb_node);
+ ret |= machine__read_build_ids(pos, with_hits);
+ }
+
+ return ret;
+}