1 files changed, 83 insertions, 44 deletions

diff --git a/tools/perf/util/build-id.c b/tools/perf/util/build-id.c
index 6b410c3d52dc..02df36b30ac5 100644
--- a/tools/perf/util/build-id.c
+++ b/tools/perf/util/build-id.c
@@ -37,6 +37,7 @@
 
 #include <linux/ctype.h>
 #include <linux/zalloc.h>
+#include <linux/string.h>
 #include <asm/bug.h>
 
 static bool no_buildid_cache;
@@ -260,10 +261,9 @@ static const char *build_id_cache__basename(bool is_kallsyms, bool is_vdso,
 	    "debug" : "elf"));
 }
 
-char *dso__build_id_filename(const struct dso *dso, char *bf, size_t size,
-			     bool is_debug)
+char *__dso__build_id_filename(const struct dso *dso, char *bf, size_t size,
+			       bool is_debug, bool is_kallsyms)
 {
-	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;
@@ -292,6 +292,14 @@ char *dso__build_id_filename(const struct dso *dso, char *bf, size_t size,
 	return bf;
 }
 
+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);
+
+	return __dso__build_id_filename(dso, bf, size, is_debug, is_kallsyms);
+}
+
 #define dsos__for_each_with_build_id(pos, head)	\
 	list_for_each_entry(pos, head, node)	\
 		if (!pos->has_build_id)		\
@@ -663,24 +671,15 @@ out:
 	return realname;
 }
 
-int build_id_cache__add_s(const char *sbuild_id, const char *name,
-			  struct nsinfo *nsi, bool is_kallsyms, bool is_vdso)
+int
+build_id_cache__add(const char *sbuild_id, const char *name, const char *realname,
+		    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 *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)
@@ -754,8 +753,25 @@ int build_id_cache__add_s(const char *sbuild_id, const char *name,
 	tmp = dir_name + strlen(buildid_dir) - 5;
 	memcpy(tmp, "../..", 5);
 
-	if (symlink(tmp, linkname) == 0)
+	if (symlink(tmp, linkname) == 0) {
+		err = 0;
+	} else if (errno == EEXIST) {
+		char path[PATH_MAX];
+		ssize_t len;
+
+		len = readlink(linkname, path, sizeof(path) - 1);
+		if (len <= 0) {
+			pr_err("Cant read link: %s\n", linkname);
+			goto out_free;
+		}
+		path[len] = '\0';
+
+		if (strcmp(tmp, path)) {
+			pr_debug("build <%s> already linked to %s\n",
+				 sbuild_id, linkname);
+		}
 		err = 0;
+	}
 
 	/* Update SDT cache : error is just warned */
 	if (realname &&
@@ -763,8 +779,6 @@ int build_id_cache__add_s(const char *sbuild_id, const char *name,
 		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);
@@ -772,6 +786,29 @@ out_free:
 	return err;
 }
 
+int build_id_cache__add_s(const char *sbuild_id, const char *name,
+			  struct nsinfo *nsi, bool is_kallsyms, bool is_vdso)
+{
+	char *realname = 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;
+	}
+
+	err = build_id_cache__add(sbuild_id, name, realname, nsi, is_kallsyms, is_vdso);
+
+out_free:
+	if (!is_kallsyms)
+		free(realname);
+	return err;
+}
+
 static int build_id_cache__add_b(const struct build_id *bid,
 				 const char *name, struct nsinfo *nsi,
 				 bool is_kallsyms, bool is_vdso)
@@ -834,12 +871,16 @@ out_free:
 	return err;
 }
 
-static int dso__cache_build_id(struct dso *dso, struct machine *machine)
+static int dso__cache_build_id(struct dso *dso, struct machine *machine,
+			       void *priv __maybe_unused)
 {
 	bool is_kallsyms = dso__is_kallsyms(dso);
 	bool is_vdso = dso__is_vdso(dso);
 	const char *name = dso->long_name;
 
+	if (!dso->has_build_id)
+		return 0;
+
 	if (dso__is_kcore(dso)) {
 		is_kallsyms = true;
 		name = machine->mmap_name;
@@ -848,43 +889,36 @@ static int dso__cache_build_id(struct dso *dso, struct machine *machine)
 				     is_kallsyms, is_vdso);
 }
 
-static int __dsos__cache_build_ids(struct list_head *head,
-				   struct machine *machine)
+static int
+machines__for_each_dso(struct machines *machines, machine__dso_t fn, void *priv)
 {
-	struct dso *pos;
-	int err = 0;
-
-	dsos__for_each_with_build_id(pos, head)
-		if (dso__cache_build_id(pos, machine))
-			err = -1;
+	int ret = machine__for_each_dso(&machines->host, fn, priv);
+	struct rb_node *nd;
 
-	return err;
-}
+	for (nd = rb_first_cached(&machines->guests); nd;
+	     nd = rb_next(nd)) {
+		struct machine *pos = rb_entry(nd, struct machine, rb_node);
 
-static int machine__cache_build_ids(struct machine *machine)
-{
-	return __dsos__cache_build_ids(&machine->dsos.head, machine);
+		ret |= machine__for_each_dso(pos, fn, priv);
+	}
+	return ret ? -1 : 0;
 }
 
-int perf_session__cache_build_ids(struct perf_session *session)
+int __perf_session__cache_build_ids(struct perf_session *session,
+				    machine__dso_t fn, void *priv)
 {
-	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);
+	return machines__for_each_dso(&session->machines, fn, priv) ?  -1 : 0;
+}
 
-	for (nd = rb_first_cached(&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;
+int perf_session__cache_build_ids(struct perf_session *session)
+{
+	return __perf_session__cache_build_ids(session, dso__cache_build_id, NULL);
 }
 
 static bool machine__read_build_ids(struct machine *machine, bool with_hits)
@@ -912,3 +946,8 @@ void build_id__init(struct build_id *bid, const u8 *data, size_t size)
 	memcpy(bid->data, data, size);
 	bid->size = size;
 }
+
+bool build_id__is_defined(const struct build_id *bid)
+{
+	return bid && bid->size ? !!memchr_inv(bid->data, 0, bid->size) : false;
+}