diff options
author | NeilBrown <neilb@suse.de> | 2011-07-26 11:19:49 +1000 |
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committer | NeilBrown <neilb@suse.de> | 2011-07-26 11:19:49 +1000 |
commit | 83206d66b65118d995c38746f21edc2bb8564b49 (patch) | |
tree | 69e1c082cb33d19a508c764da613e0c6b5ced27b | |
parent | ffd96e35c16a99fdb490cc5723b8e32135ae5883 (diff) | |
download | linux-3.10-83206d66b65118d995c38746f21edc2bb8564b49.tar.gz linux-3.10-83206d66b65118d995c38746f21edc2bb8564b49.tar.bz2 linux-3.10-83206d66b65118d995c38746f21edc2bb8564b49.zip |
md/raid5: Remove use of sh->lock in sync_request
This is the start of a series of patches to remove sh->lock.
sync_request takes sh->lock before setting STRIPE_SYNCING to ensure
there is no race with testing it in handle_stripe[56].
Instead, use a new flag STRIPE_SYNC_REQUESTED and test it early
in handle_stripe[56] (after getting the same lock) and perform the
same set/clear operations if it was set.
Signed-off-by: NeilBrown <neilb@suse.de>
Reviewed-by: Namhyung Kim <namhyung@gmail.com>
-rw-r--r-- | drivers/md/raid5.c | 13 | ||||
-rw-r--r-- | drivers/md/raid5.h | 33 |
2 files changed, 27 insertions, 19 deletions
diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c index 71480646a45..f2f2ab32969 100644 --- a/drivers/md/raid5.c +++ b/drivers/md/raid5.c @@ -3022,6 +3022,10 @@ static void handle_stripe5(struct stripe_head *sh) sh->reconstruct_state); spin_lock(&sh->lock); + if (test_and_clear_bit(STRIPE_SYNC_REQUESTED, &sh->state)) { + set_bit(STRIPE_SYNCING, &sh->state); + clear_bit(STRIPE_INSYNC, &sh->state); + } clear_bit(STRIPE_HANDLE, &sh->state); clear_bit(STRIPE_DELAYED, &sh->state); @@ -3313,6 +3317,10 @@ static void handle_stripe6(struct stripe_head *sh) memset(&s, 0, sizeof(s)); spin_lock(&sh->lock); + if (test_and_clear_bit(STRIPE_SYNC_REQUESTED, &sh->state)) { + set_bit(STRIPE_SYNCING, &sh->state); + clear_bit(STRIPE_INSYNC, &sh->state); + } clear_bit(STRIPE_HANDLE, &sh->state); clear_bit(STRIPE_DELAYED, &sh->state); @@ -4373,10 +4381,7 @@ static inline sector_t sync_request(mddev_t *mddev, sector_t sector_nr, int *ski bitmap_start_sync(mddev->bitmap, sector_nr, &sync_blocks, still_degraded); - spin_lock(&sh->lock); - set_bit(STRIPE_SYNCING, &sh->state); - clear_bit(STRIPE_INSYNC, &sh->state); - spin_unlock(&sh->lock); + set_bit(STRIPE_SYNC_REQUESTED, &sh->state); handle_stripe(sh); release_stripe(sh); diff --git a/drivers/md/raid5.h b/drivers/md/raid5.h index 3ca77a2613b..a33001137bf 100644 --- a/drivers/md/raid5.h +++ b/drivers/md/raid5.h @@ -289,21 +289,24 @@ struct r6_state { /* * Stripe state */ -#define STRIPE_HANDLE 2 -#define STRIPE_SYNCING 3 -#define STRIPE_INSYNC 4 -#define STRIPE_PREREAD_ACTIVE 5 -#define STRIPE_DELAYED 6 -#define STRIPE_DEGRADED 7 -#define STRIPE_BIT_DELAY 8 -#define STRIPE_EXPANDING 9 -#define STRIPE_EXPAND_SOURCE 10 -#define STRIPE_EXPAND_READY 11 -#define STRIPE_IO_STARTED 12 /* do not count towards 'bypass_count' */ -#define STRIPE_FULL_WRITE 13 /* all blocks are set to be overwritten */ -#define STRIPE_BIOFILL_RUN 14 -#define STRIPE_COMPUTE_RUN 15 -#define STRIPE_OPS_REQ_PENDING 16 +enum { + STRIPE_HANDLE, + STRIPE_SYNC_REQUESTED, + STRIPE_SYNCING, + STRIPE_INSYNC, + STRIPE_PREREAD_ACTIVE, + STRIPE_DELAYED, + STRIPE_DEGRADED, + STRIPE_BIT_DELAY, + STRIPE_EXPANDING, + STRIPE_EXPAND_SOURCE, + STRIPE_EXPAND_READY, + STRIPE_IO_STARTED, /* do not count towards 'bypass_count' */ + STRIPE_FULL_WRITE, /* all blocks are set to be overwritten */ + STRIPE_BIOFILL_RUN, + STRIPE_COMPUTE_RUN, + STRIPE_OPS_REQ_PENDING, +}; /* * Operation request flags |