| From 257a4b42af7586fab4eaec7f04e6896b86551843 Mon Sep 17 00:00:00 2001 |
| From: Dan Williams <dan.j.williams@intel.com> |
| Date: Tue, 8 Nov 2011 16:22:06 +1100 |
| Subject: md/raid5: STRIPE_ACTIVE has lock semantics, add barriers |
| |
| From: Dan Williams <dan.j.williams@intel.com> |
| |
| commit 257a4b42af7586fab4eaec7f04e6896b86551843 upstream. |
| |
| 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 <dan.j.williams@intel.com> |
| Signed-off-by: NeilBrown <neilb@suse.de> |
| Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de> |
| |
| --- |
| drivers/md/raid5.c | 4 ++-- |
| 1 file changed, 2 insertions(+), 2 deletions(-) |
| |
| --- a/drivers/md/raid5.c |
| +++ b/drivers/md/raid5.c |
| @@ -3116,7 +3116,7 @@ static void handle_stripe(struct stripe_ |
| 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); |
| @@ -3381,7 +3381,7 @@ finish: |
| |
| return_io(s.return_bi); |
| |
| - clear_bit(STRIPE_ACTIVE, &sh->state); |
| + clear_bit_unlock(STRIPE_ACTIVE, &sh->state); |
| } |
| |
| static void raid5_activate_delayed(raid5_conf_t *conf) |
