This is a note to let you know that I've just added the patch titled
arm64: stacktrace: use non-atomic __set_bit
to the 5.19-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
arm64-stacktrace-use-non-atomic-__set_bit.patch
and it can be found in the queue-5.19 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit a5ccbbee3b95a0c303ed82515c073b26e363da28
Author: Andrey Konovalov <andreyknvl@xxxxxxxxx>
Date: Mon May 23 16:51:52 2022 +0200
arm64: stacktrace: use non-atomic __set_bit
[ Upstream commit 446297b28a21244e4045026c4599d1b14a67e2ce ]
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@xxxxxxx>
Acked-by: Mark Rutland <mark.rutland@xxxxxxx>
Signed-off-by: Andrey Konovalov <andreyknvl@xxxxxxxxxx>
Link: https://lore.kernel.org/r/23dfa36d1cc91e4a1059945b7834eac22fb9854d.1653317461.git.andreyknvl@xxxxxxxxxx
Signed-off-by: Will Deacon <will@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/arch/arm64/kernel/stacktrace.c b/arch/arm64/kernel/stacktrace.c
index c246e8d9f95b..d6bef106e37e 100644
--- a/arch/arm64/kernel/stacktrace.c
+++ b/arch/arm64/kernel/stacktrace.c
@@ -117,7 +117,7 @@ static int notrace unwind_next(struct task_struct *tsk,
if (fp <= state->prev_fp)
return -EINVAL;
} else {
- set_bit(state->prev_type, state->stacks_done);
+ __set_bit(state->prev_type, state->stacks_done);
}
/*
