diff options
| author | NeilBrown <neilb@suse.de> | 2006-10-03 01:15:53 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@g5.osdl.org> | 2006-10-03 08:04:18 -0700 |
| commit | c04be0aa82ff535e3676ab3e573957bdeef41879 (patch) | |
| tree | 8481ab270218bed246eb02b3ba04a4b84d4e90d0 /drivers/md/raid10.c | |
| parent | 11ce99e625fe2718ad2682bfdd99070b337e6252 (diff) | |
[PATCH] md: Improve locking around error handling
The error handling routines don't use proper locking, and so two concurrent
errors could trigger a problem.
So:
- use test-and-set and test-and-clear to synchonise
the In_sync bits with the ->degraded count
- use the spinlock to protect updates to the
degraded count (could use an atomic_t but that
would be a bigger change in code, and isn't
really justified)
- remove un-necessary locking in raid5
Signed-off-by: Neil Brown <neilb@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to 'drivers/md/raid10.c')
| -rw-r--r-- | drivers/md/raid10.c | 12 |
1 files changed, 8 insertions, 4 deletions
diff --git a/drivers/md/raid10.c b/drivers/md/raid10.c index 233a4faede9..64f8016ab74 100644 --- a/drivers/md/raid10.c +++ b/drivers/md/raid10.c @@ -950,14 +950,16 @@ static void error(mddev_t *mddev, mdk_rdev_t *rdev) * really dead" tests... */ return; - if (test_bit(In_sync, &rdev->flags)) { + if (test_and_clear_bit(In_sync, &rdev->flags)) { + unsigned long flags; + spin_lock_irqsave(&conf->device_lock, flags); mddev->degraded++; + spin_unlock_irqrestore(&conf->device_lock, flags); /* * if recovery is running, make sure it aborts. */ set_bit(MD_RECOVERY_ERR, &mddev->recovery); } - clear_bit(In_sync, &rdev->flags); set_bit(Faulty, &rdev->flags); set_bit(MD_CHANGE_DEVS, &mddev->flags); printk(KERN_ALERT "raid10: Disk failure on %s, disabling device. \n" @@ -1033,9 +1035,11 @@ static int raid10_spare_active(mddev_t *mddev) tmp = conf->mirrors + i; if (tmp->rdev && !test_bit(Faulty, &tmp->rdev->flags) - && !test_bit(In_sync, &tmp->rdev->flags)) { + && !test_and_set_bit(In_sync, &tmp->rdev->flags)) { + unsigned long flags; + spin_lock_irqsave(&conf->device_lock, flags); mddev->degraded--; - set_bit(In_sync, &tmp->rdev->flags); + spin_unlock_irqrestore(&conf->device_lock, flags); } } |