diff mbox series

[v2,2/2] arm64: stacktrace: use non-atomic __set_bit

Message ID 23dfa36d1cc91e4a1059945b7834eac22fb9854d.1653317461.git.andreyknvl@google.com (mailing list archive)
State New, archived
Headers show
Series [v2,1/2] arm64: kasan: do not instrument stacktrace.c | expand

Commit Message

andrey.konovalov@linux.dev May 23, 2022, 2:51 p.m. UTC 
From: Andrey Konovalov <andreyknvl@google.com>

Use the non-atomic version of set_bit() in arch/arm64/kernel/stacktrace.c,
as there is no concurrent accesses to frame->prev_type.

This speeds up stack trace collection and improves the boot time of
Generic KASAN by 2-5%.

Suggested-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
---
 arch/arm64/kernel/stacktrace.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
diff mbox series

Patch

diff --git a/arch/arm64/kernel/stacktrace.c b/arch/arm64/kernel/stacktrace.c
index 33e96ae4b15f..03593d451b0a 100644
--- a/arch/arm64/kernel/stacktrace.c
+++ b/arch/arm64/kernel/stacktrace.c
@@ -103,7 +103,7 @@  static int notrace unwind_frame(struct task_struct *tsk,
 		if (fp <= frame->prev_fp)
 			return -EINVAL;
 	} else {
-		set_bit(frame->prev_type, frame->stacks_done);
+		__set_bit(frame->prev_type, frame->stacks_done);
 	}
 
 	/*