diff options
| -rw-r--r-- | drivers/md/raid5.c | 62 | ||||
| -rw-r--r-- | drivers/md/raid5.h | 1 |
2 files changed, 60 insertions, 3 deletions
diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c index bde9da2baa39..978ba9b7a3c4 100644 --- a/drivers/md/raid5.c +++ b/drivers/md/raid5.c @@ -471,7 +471,8 @@ get_active_stripe(struct r5conf *conf, sector_t sector, } else { if (atomic_read(&sh->count)) { BUG_ON(!list_empty(&sh->lru) - && !test_bit(STRIPE_EXPANDING, &sh->state)); + && !test_bit(STRIPE_EXPANDING, &sh->state) + && !test_bit(STRIPE_ON_UNPLUG_LIST, &sh->state)); } else { if (!test_bit(STRIPE_HANDLE, &sh->state)) atomic_inc(&conf->active_stripes); @@ -3988,6 +3989,62 @@ static struct stripe_head *__get_priority_stripe(struct r5conf *conf) return sh; } +struct raid5_plug_cb { + struct blk_plug_cb cb; + struct list_head list; +}; + +static void raid5_unplug(struct blk_plug_cb *blk_cb, bool from_schedule) +{ + struct raid5_plug_cb *cb = container_of( + blk_cb, struct raid5_plug_cb, cb); + struct stripe_head *sh; + struct mddev *mddev = cb->cb.data; + struct r5conf *conf = mddev->private; + + if (cb->list.next && !list_empty(&cb->list)) { + spin_lock_irq(&conf->device_lock); + while (!list_empty(&cb->list)) { + sh = list_first_entry(&cb->list, struct stripe_head, lru); + list_del_init(&sh->lru); + /* + * avoid race release_stripe_plug() sees + * STRIPE_ON_UNPLUG_LIST clear but the stripe + * is still in our list + */ + smp_mb__before_clear_bit(); + clear_bit(STRIPE_ON_UNPLUG_LIST, &sh->state); + __release_stripe(conf, sh); + } + spin_unlock_irq(&conf->device_lock); + } + kfree(cb); +} + +static void release_stripe_plug(struct mddev *mddev, + struct stripe_head *sh) +{ + struct blk_plug_cb *blk_cb = blk_check_plugged( + raid5_unplug, mddev, + sizeof(struct raid5_plug_cb)); + struct raid5_plug_cb *cb; + + if (!blk_cb) { + release_stripe(sh); + return; + } + + cb = container_of(blk_cb, struct raid5_plug_cb, cb); + + if (cb->list.next == NULL) + INIT_LIST_HEAD(&cb->list); + + if (!test_and_set_bit(STRIPE_ON_UNPLUG_LIST, &sh->state)) + list_add_tail(&sh->lru, &cb->list); + else + release_stripe(sh); +} + static void make_request(struct mddev *mddev, struct bio * bi) { struct r5conf *conf = mddev->private; @@ -4116,8 +4173,7 @@ static void make_request(struct mddev *mddev, struct bio * bi) if ((bi->bi_rw & REQ_SYNC) && !test_and_set_bit(STRIPE_PREREAD_ACTIVE, &sh->state)) atomic_inc(&conf->preread_active_stripes); - mddev_check_plugged(mddev); - release_stripe(sh); + release_stripe_plug(mddev, sh); } else { /* cannot get stripe for read-ahead, just give-up */ clear_bit(BIO_UPTODATE, &bi->bi_flags); diff --git a/drivers/md/raid5.h b/drivers/md/raid5.h index 2164021f3b5f..9a7b36f0a425 100644 --- a/drivers/md/raid5.h +++ b/drivers/md/raid5.h @@ -319,6 +319,7 @@ enum { STRIPE_BIOFILL_RUN, STRIPE_COMPUTE_RUN, STRIPE_OPS_REQ_PENDING, + STRIPE_ON_UNPLUG_LIST, }; /* |