diff options
| author | Dan Williams <dan.j.williams@intel.com> | 2008-05-12 14:02:12 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2008-05-13 08:02:24 -0700 |
| commit | c8894419acf5e56851de9741c5047bebd78acd1f (patch) | |
| tree | 6294b87ebf31d577cd48880a201ff4b1a6a50ffc /drivers/md/raid5.c | |
| parent | 3f275ea3086054205795972b8e87f2046fd3de98 (diff) | |
| download | lwn-c8894419acf5e56851de9741c5047bebd78acd1f.tar.gz lwn-c8894419acf5e56851de9741c5047bebd78acd1f.zip | |
md: fix raid5 'repair' operations
commit bd2ab67030e9116f1e4aae1289220255412b37fd "md: close a livelock window
in handle_parity_checks5" introduced a bug in handling 'repair' operations.
After a repair operation completes we clear the state bits tracking this
operation. However, they are cleared too early and this results in the code
deciding to re-run the parity check operation. Since we have done the repair
in memory the second check does not find a mismatch and thus does not do a
writeback.
Test results:
$ echo repair > /sys/block/md0/md/sync_action
$ cat /sys/block/md0/md/mismatch_cnt
51072
$ echo repair > /sys/block/md0/md/sync_action
$ cat /sys/block/md0/md/mismatch_cnt
0
(also fix incorrect indentation)
Cc: <stable@kernel.org>
Tested-by: George Spelvin <linux@horizon.com>
Acked-by: NeilBrown <neilb@suse.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'drivers/md/raid5.c')
| -rw-r--r-- | drivers/md/raid5.c | 25 |
1 files changed, 13 insertions, 12 deletions
diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c index 087eee0cb809..ee0ea9183080 100644 --- a/drivers/md/raid5.c +++ b/drivers/md/raid5.c @@ -2369,8 +2369,8 @@ static void handle_parity_checks5(raid5_conf_t *conf, struct stripe_head *sh, /* complete a check operation */ if (test_and_clear_bit(STRIPE_OP_CHECK, &sh->ops.complete)) { - clear_bit(STRIPE_OP_CHECK, &sh->ops.ack); - clear_bit(STRIPE_OP_CHECK, &sh->ops.pending); + clear_bit(STRIPE_OP_CHECK, &sh->ops.ack); + clear_bit(STRIPE_OP_CHECK, &sh->ops.pending); if (s->failed == 0) { if (sh->ops.zero_sum_result == 0) /* parity is correct (on disc, @@ -2400,16 +2400,6 @@ static void handle_parity_checks5(raid5_conf_t *conf, struct stripe_head *sh, canceled_check = 1; /* STRIPE_INSYNC is not set */ } - /* check if we can clear a parity disk reconstruct */ - if (test_bit(STRIPE_OP_COMPUTE_BLK, &sh->ops.complete) && - test_bit(STRIPE_OP_MOD_REPAIR_PD, &sh->ops.pending)) { - - clear_bit(STRIPE_OP_MOD_REPAIR_PD, &sh->ops.pending); - clear_bit(STRIPE_OP_COMPUTE_BLK, &sh->ops.complete); - clear_bit(STRIPE_OP_COMPUTE_BLK, &sh->ops.ack); - clear_bit(STRIPE_OP_COMPUTE_BLK, &sh->ops.pending); - } - /* start a new check operation if there are no failures, the stripe is * not insync, and a repair is not in flight */ @@ -2424,6 +2414,17 @@ static void handle_parity_checks5(raid5_conf_t *conf, struct stripe_head *sh, } } + /* check if we can clear a parity disk reconstruct */ + if (test_bit(STRIPE_OP_COMPUTE_BLK, &sh->ops.complete) && + test_bit(STRIPE_OP_MOD_REPAIR_PD, &sh->ops.pending)) { + + clear_bit(STRIPE_OP_MOD_REPAIR_PD, &sh->ops.pending); + clear_bit(STRIPE_OP_COMPUTE_BLK, &sh->ops.complete); + clear_bit(STRIPE_OP_COMPUTE_BLK, &sh->ops.ack); + clear_bit(STRIPE_OP_COMPUTE_BLK, &sh->ops.pending); + } + + /* Wait for check parity and compute block operations to complete * before write-back. If a failure occurred while the check operation * was in flight we need to cycle this stripe through handle_stripe |