4 files changed, 59 insertions, 24 deletions

diff --git a/tools/perf/util/event.h b/tools/perf/util/event.h
index 34c6fcb82d92..1f771ce3a957 100644
--- a/tools/perf/util/event.h
+++ b/tools/perf/util/event.h
@@ -69,6 +69,13 @@ struct build_id_event {
         char                     filename[];
 };
 
+struct build_id_list {
+        struct build_id_event   event;
+        struct list_head        list;
+        const char              *dso_name;
+        int                     len;
+};
+
 typedef union event_union {
         struct perf_event_header        header;
         struct ip_event                 ip;
diff --git a/tools/perf/util/header.c b/tools/perf/util/header.c
index a4d0bbef9a43..2f702c23f71a 100644
--- a/tools/perf/util/header.c
+++ b/tools/perf/util/header.c
@@ -174,29 +174,18 @@ static void do_write(int fd, void *buf, size_t size)
         }
 }
 
-static bool write_buildid_table(int fd)
+static void write_buildid_table(int fd, struct list_head *id_head)
 {
-        struct dso *pos;
-        bool have_buildid = false;
-
-        list_for_each_entry(pos, &dsos, node) {
-                struct build_id_event b;
-                size_t len;
-
-                if (filename__read_build_id(pos->long_name,
-                                            &b.build_id,
-                                            sizeof(b.build_id)) < 0)
-                        continue;
-                have_buildid = true;
-                memset(&b.header, 0, sizeof(b.header));
-                len = strlen(pos->long_name) + 1;
-                len = ALIGN(len, 64);
-                b.header.size = sizeof(b) + len;
-                do_write(fd, &b, sizeof(b));
-                do_write(fd, pos->long_name, len);
-        }
+        struct build_id_list *iter, *next;
+
+        list_for_each_entry_safe(iter, next, id_head, list) {
+                struct build_id_event *b = &iter->event;
 
-        return have_buildid;
+                do_write(fd, b, sizeof(*b));
+                do_write(fd, (void *)iter->dso_name, iter->len);
+                list_del(&iter->list);
+                free(iter);
+        }
 }
 
 static void
@@ -226,10 +215,14 @@ perf_header__adds_write(struct perf_header *self, int fd, bool at_exit)
         }
 
         if (at_exit) {
-                lseek(fd, self->data_offset + self->data_size, SEEK_SET);
-                if (write_buildid_table(fd))
+                LIST_HEAD(id_list);
+
+                if (fetch_build_id_table(&id_list)) {
+                        lseek(fd, self->data_offset + self->data_size, SEEK_SET);
                         perf_header__set_feat(self, HEADER_BUILD_ID);
-                lseek(fd, cur_offset, SEEK_SET);
+                        write_buildid_table(fd, &id_list);
+                        lseek(fd, cur_offset, SEEK_SET);
+                }
         }
 };
 
diff --git a/tools/perf/util/symbol.c b/tools/perf/util/symbol.c
index a2e95ce1f223..9c286db62003 100644
--- a/tools/perf/util/symbol.c
+++ b/tools/perf/util/symbol.c
@@ -851,6 +851,40 @@ out_close:
         return err;
 }
 
+bool fetch_build_id_table(struct list_head *head)
+{
+        bool have_buildid = false;
+        struct dso *pos;
+
+        list_for_each_entry(pos, &dsos, node) {
+                struct build_id_list *new;
+                struct build_id_event b;
+                size_t len;
+
+                if (filename__read_build_id(pos->long_name,
+                                            &b.build_id,
+                                            sizeof(b.build_id)) < 0)
+                        continue;
+                have_buildid = true;
+                memset(&b.header, 0, sizeof(b.header));
+                len = strlen(pos->long_name) + 1;
+                len = ALIGN(len, 64);
+                b.header.size = sizeof(b) + len;
+
+                new = malloc(sizeof(*new));
+                if (!new)
+                        die("No memory\n");
+
+                memcpy(&new->event, &b, sizeof(b));
+                new->dso_name = pos->long_name;
+                new->len = len;
+
+                list_add_tail(&new->list, head);
+        }
+
+        return have_buildid;
+}
+
 int filename__read_build_id(const char *filename, void *bf, size_t size)
 {
         int fd, err = -1;
diff --git a/tools/perf/util/symbol.h b/tools/perf/util/symbol.h
index f8c1899af483..0a34a5493f1b 100644
--- a/tools/perf/util/symbol.h
+++ b/tools/perf/util/symbol.h
@@ -86,6 +86,7 @@ char dso__symtab_origin(const struct dso *self);
 void dso__set_build_id(struct dso *self, void *build_id);
 
 int filename__read_build_id(const char *filename, void *bf, size_t size);
+bool fetch_build_id_table(struct list_head *head);
 int build_id__sprintf(u8 *self, int len, char *bf);
 
 int load_kernel(symbol_filter_t filter);