diff options
author | Guoqing Jiang <gqjiang@suse.com> | 2016-05-03 22:22:13 -0400 |
---|---|---|
committer | Shaohua Li <shli@fb.com> | 2016-05-09 09:24:02 -0700 |
commit | 85ad1d13ee9b3db00615ea24b031c15e5ba14fd1 (patch) | |
tree | ff8cd0a32ae44fa7d306cee622c9eea96a9de076 /drivers/md/raid10.c | |
parent | fe67d19a2d7b31f1c29efbe1819c921d4a9bb012 (diff) | |
download | linux-85ad1d13ee9b3db00615ea24b031c15e5ba14fd1.tar.bz2 |
md: set MD_CHANGE_PENDING in a atomic region
Some code waits for a metadata update by:
1. flagging that it is needed (MD_CHANGE_DEVS or MD_CHANGE_CLEAN)
2. setting MD_CHANGE_PENDING and waking the management thread
3. waiting for MD_CHANGE_PENDING to be cleared
If the first two are done without locking, the code in md_update_sb()
which checks if it needs to repeat might test if an update is needed
before step 1, then clear MD_CHANGE_PENDING after step 2, resulting
in the wait returning early.
So make sure all places that set MD_CHANGE_PENDING are atomicial, and
bit_clear_unless (suggested by Neil) is introduced for the purpose.
Cc: Martin Kepplinger <martink@posteo.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Sasha Levin <sasha.levin@oracle.com>
Cc: <linux-kernel@vger.kernel.org>
Reviewed-by: NeilBrown <neilb@suse.com>
Signed-off-by: Guoqing Jiang <gqjiang@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
Diffstat (limited to 'drivers/md/raid10.c')
-rw-r--r-- | drivers/md/raid10.c | 8 |
1 files changed, 4 insertions, 4 deletions
diff --git a/drivers/md/raid10.c b/drivers/md/raid10.c index 84e24e648165..c7de2a53e625 100644 --- a/drivers/md/raid10.c +++ b/drivers/md/raid10.c @@ -1102,8 +1102,8 @@ static void __make_request(struct mddev *mddev, struct bio *bio) bio->bi_iter.bi_sector < conf->reshape_progress))) { /* Need to update reshape_position in metadata */ mddev->reshape_position = conf->reshape_progress; - set_bit(MD_CHANGE_DEVS, &mddev->flags); - set_bit(MD_CHANGE_PENDING, &mddev->flags); + set_mask_bits(&mddev->flags, 0, + BIT(MD_CHANGE_DEVS) | BIT(MD_CHANGE_PENDING)); md_wakeup_thread(mddev->thread); wait_event(mddev->sb_wait, !test_bit(MD_CHANGE_PENDING, &mddev->flags)); @@ -1591,8 +1591,8 @@ static void raid10_error(struct mddev *mddev, struct md_rdev *rdev) set_bit(MD_RECOVERY_INTR, &mddev->recovery); set_bit(Blocked, &rdev->flags); set_bit(Faulty, &rdev->flags); - set_bit(MD_CHANGE_DEVS, &mddev->flags); - set_bit(MD_CHANGE_PENDING, &mddev->flags); + set_mask_bits(&mddev->flags, 0, + BIT(MD_CHANGE_DEVS) | BIT(MD_CHANGE_PENDING)); spin_unlock_irqrestore(&conf->device_lock, flags); printk(KERN_ALERT "md/raid10:%s: Disk failure on %s, disabling device.\n" |