From 4a936edc317005e8cd2b501e7865721bec104544 Mon Sep 17 00:00:00 2001 From: Namhyung Kim Date: Mon, 18 May 2015 09:30:40 +0900 Subject: [PATCH] perf symbols: Protect dso symbol loading using a mutex Add mutex to protect it from concurrent dso__load(). Signed-off-by: Namhyung Kim Cc: Adrian Hunter Cc: Andi Kleen Cc: David Ahern Cc: Frederic Weisbecker Cc: Jiri Olsa Cc: Peter Zijlstra Cc: Stephane Eranian Link: http://lkml.kernel.org/r/1431909055-21442-26-git-send-email-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/util/dso.c | 2 ++ tools/perf/util/dso.h | 1 + tools/perf/util/symbol.c | 34 ++++++++++++++++++++++++---------- 3 files changed, 27 insertions(+), 10 deletions(-) diff --git a/tools/perf/util/dso.c b/tools/perf/util/dso.c index 13d9ae0bd15c..482d6024ef13 100644 --- a/tools/perf/util/dso.c +++ b/tools/perf/util/dso.c @@ -936,6 +936,7 @@ struct dso *dso__new(const char *name) RB_CLEAR_NODE(&dso->rb_node); INIT_LIST_HEAD(&dso->node); INIT_LIST_HEAD(&dso->data.open_entry); + pthread_mutex_init(&dso->lock, NULL); } return dso; @@ -966,6 +967,7 @@ void dso__delete(struct dso *dso) dso_cache__free(&dso->data.cache); dso__free_a2l(dso); zfree(&dso->symsrc_filename); + pthread_mutex_destroy(&dso->lock); free(dso); } diff --git a/tools/perf/util/dso.h b/tools/perf/util/dso.h index 3d79c749934c..b26ec3ab1336 100644 --- a/tools/perf/util/dso.h +++ b/tools/perf/util/dso.h @@ -129,6 +129,7 @@ struct dsos { struct auxtrace_cache; struct dso { + pthread_mutex_t lock; struct list_head node; struct rb_node rb_node; /* rbtree node sorted by long name */ struct rb_root symbols[MAP__NR_TYPES]; diff --git a/tools/perf/util/symbol.c b/tools/perf/util/symbol.c index 45ba48a7acb3..9ef8b8946b11 100644 --- a/tools/perf/util/symbol.c +++ b/tools/perf/util/symbol.c @@ -1383,12 +1383,22 @@ int dso__load(struct dso *dso, struct map *map, symbol_filter_t filter) 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 @@ int dso__load(struct dso *dso, struct map *map, symbol_filter_t filter) 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 @@ int dso__load(struct dso *dso, struct map *map, symbol_filter_t filter) 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 @@ int dso__load(struct dso *dso, struct map *map, symbol_filter_t filter) 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; }