[PATCH] perf_counter: more barrier in blank weak function

Yinghai Lu
2008-12-27T05:06:36Z

Impact: fix panic possible panic etc

some compiler seems to inline the weak global function if no line in it

Signed-off-by: Yinghai Lu <yinghai@kernel.org>

diff --git a/kernel/perf_counter.c b/kernel/perf_counter.c
index d7a79f3..37f7716 100644
--- a/kernel/perf_counter.c
+++ b/kernel/perf_counter.c
@@ -45,8 +45,8 @@ hw_perf_counter_init(struct perf_counter *counter)
}

u64 __weak hw_perf_save_disable(void) { return 0; }
-void __weak hw_perf_restore(u64 ctrl) { }
-void __weak hw_perf_counter_setup(void) { }
+void __weak hw_perf_restore(u64 ctrl) { barrier(); }
+void __weak hw_perf_counter_setup(void) { barrier(); }

static void
list_add_counter(struct perf_counter *counter, struct perf_counter_context *ctx)