From 257a4b42af7586fab4eaec7f04e6896b86551843 Mon Sep 17 00:00:00 2001 From: Dan Williams Date: Tue, 8 Nov 2011 16:22:06 +1100 Subject: [PATCH] md/raid5: STRIPE_ACTIVE has lock semantics, add barriers All updates that occur under STRIPE_ACTIVE should be globally visible when STRIPE_ACTIVE clears. test_and_set_bit() implies a barrier, but clear_bit() does not. This is suitable for 3.1-stable. Signed-off-by: Dan Williams Signed-off-by: NeilBrown Cc: stable@kernel.org --- drivers/md/raid5.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c index 318bdae9b56c..297e26092178 100644 --- a/drivers/md/raid5.c +++ b/drivers/md/raid5.c @@ -3110,7 +3110,7 @@ static void handle_stripe(struct stripe_head *sh) struct r5dev *pdev, *qdev; clear_bit(STRIPE_HANDLE, &sh->state); - if (test_and_set_bit(STRIPE_ACTIVE, &sh->state)) { + if (test_and_set_bit_lock(STRIPE_ACTIVE, &sh->state)) { /* already being handled, ensure it gets handled * again when current action finishes */ set_bit(STRIPE_HANDLE, &sh->state); @@ -3375,7 +3375,7 @@ finish: return_io(s.return_bi); - clear_bit(STRIPE_ACTIVE, &sh->state); + clear_bit_unlock(STRIPE_ACTIVE, &sh->state); } static void raid5_activate_delayed(struct r5conf *conf) -- 2.39.5