perf symbols: Protect dso symbol loading using a mutex
Add mutex to protect it from concurrent dso__load().
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: David Ahern <dsahern@gmail.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1431909055-21442-26-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
diff --git a/tools/perf/util/symbol.c b/tools/perf/util/symbol.c
index 45ba48a..9ef8b89 100644
--- a/tools/perf/util/symbol.c
+++ b/tools/perf/util/symbol.c
@@ -1383,12 +1383,22 @@
struct symsrc *syms_ss = NULL, *runtime_ss = NULL;
bool kmod;
- dso__set_loaded(dso, map->type);
+ pthread_mutex_lock(&dso->lock);
- if (dso->kernel == DSO_TYPE_KERNEL)
- return dso__load_kernel_sym(dso, map, filter);
- else if (dso->kernel == DSO_TYPE_GUEST_KERNEL)
- return dso__load_guest_kernel_sym(dso, map, filter);
+ /* check again under the dso->lock */
+ if (dso__loaded(dso, map->type)) {
+ ret = 1;
+ goto out;
+ }
+
+ if (dso->kernel) {
+ if (dso->kernel == DSO_TYPE_KERNEL)
+ ret = dso__load_kernel_sym(dso, map, filter);
+ else if (dso->kernel == DSO_TYPE_GUEST_KERNEL)
+ ret = dso__load_guest_kernel_sym(dso, map, filter);
+
+ goto out;
+ }
if (map->groups && map->groups->machine)
machine = map->groups->machine;
@@ -1401,18 +1411,18 @@
struct stat st;
if (lstat(dso->name, &st) < 0)
- return -1;
+ goto out;
if (st.st_uid && (st.st_uid != geteuid())) {
pr_warning("File %s not owned by current user or root, "
"ignoring it.\n", dso->name);
- return -1;
+ goto out;
}
ret = dso__load_perf_map(dso, map, filter);
dso->symtab_type = ret > 0 ? DSO_BINARY_TYPE__JAVA_JIT :
DSO_BINARY_TYPE__NOT_FOUND;
- return ret;
+ goto out;
}
if (machine)
@@ -1420,7 +1430,7 @@
name = malloc(PATH_MAX);
if (!name)
- return -1;
+ goto out;
kmod = dso->symtab_type == DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE ||
dso->symtab_type == DSO_BINARY_TYPE__SYSTEM_PATH_KMODULE_COMP ||
@@ -1501,7 +1511,11 @@
out_free:
free(name);
if (ret < 0 && strstr(dso->name, " (deleted)") != NULL)
- return 0;
+ ret = 0;
+out:
+ dso__set_loaded(dso, map->type);
+ pthread_mutex_unlock(&dso->lock);
+
return ret;
}