diff options
Diffstat (limited to 'drivers/md/raid10.c')
| -rw-r--r-- | drivers/md/raid10.c | 87 |
1 files changed, 60 insertions, 27 deletions
diff --git a/drivers/md/raid10.c b/drivers/md/raid10.c index 017f58113c3..32389d2f18f 100644 --- a/drivers/md/raid10.c +++ b/drivers/md/raid10.c @@ -537,7 +537,8 @@ static int read_balance(conf_t *conf, r10bio_t *r10_bio) current_distance = abs(r10_bio->devs[slot].addr - conf->mirrors[disk].head_position); - /* Find the disk whose head is closest */ + /* Find the disk whose head is closest, + * or - for far > 1 - find the closest to partition beginning */ for (nslot = slot; nslot < conf->copies; nslot++) { int ndisk = r10_bio->devs[nslot].devnum; @@ -557,8 +558,13 @@ static int read_balance(conf_t *conf, r10bio_t *r10_bio) slot = nslot; break; } - new_distance = abs(r10_bio->devs[nslot].addr - - conf->mirrors[ndisk].head_position); + + /* for far > 1 always use the lowest address */ + if (conf->far_copies > 1) + new_distance = r10_bio->devs[nslot].addr; + else + new_distance = abs(r10_bio->devs[nslot].addr - + conf->mirrors[ndisk].head_position); if (new_distance < current_distance) { current_distance = new_distance; disk = ndisk; @@ -629,7 +635,36 @@ static int raid10_congested(void *data, int bits) return ret; } - +static int flush_pending_writes(conf_t *conf) +{ + /* Any writes that have been queued but are awaiting + * bitmap updates get flushed here. + * We return 1 if any requests were actually submitted. + */ + int rv = 0; + + spin_lock_irq(&conf->device_lock); + + if (conf->pending_bio_list.head) { + struct bio *bio; + bio = bio_list_get(&conf->pending_bio_list); + blk_remove_plug(conf->mddev->queue); + spin_unlock_irq(&conf->device_lock); + /* flush any pending bitmap writes to disk + * before proceeding w/ I/O */ + bitmap_unplug(conf->mddev->bitmap); + + while (bio) { /* submit pending writes */ + struct bio *next = bio->bi_next; + bio->bi_next = NULL; + generic_make_request(bio); + bio = next; + } + rv = 1; + } else + spin_unlock_irq(&conf->device_lock); + return rv; +} /* Barriers.... * Sometimes we need to suspend IO while we do something else, * either some resync/recovery, or reconfigure the array. @@ -712,15 +747,23 @@ static void freeze_array(conf_t *conf) /* stop syncio and normal IO and wait for everything to * go quiet. * We increment barrier and nr_waiting, and then - * wait until barrier+nr_pending match nr_queued+2 + * wait until nr_pending match nr_queued+1 + * This is called in the context of one normal IO request + * that has failed. Thus any sync request that might be pending + * will be blocked by nr_pending, and we need to wait for + * pending IO requests to complete or be queued for re-try. + * Thus the number queued (nr_queued) plus this request (1) + * must match the number of pending IOs (nr_pending) before + * we continue. */ spin_lock_irq(&conf->resync_lock); conf->barrier++; conf->nr_waiting++; wait_event_lock_irq(conf->wait_barrier, - conf->barrier+conf->nr_pending == conf->nr_queued+2, + conf->nr_pending == conf->nr_queued+1, conf->resync_lock, - raid10_unplug(conf->mddev->queue)); + ({ flush_pending_writes(conf); + raid10_unplug(conf->mddev->queue); })); spin_unlock_irq(&conf->resync_lock); } @@ -892,6 +935,9 @@ static int make_request(struct request_queue *q, struct bio * bio) blk_plug_device(mddev->queue); spin_unlock_irqrestore(&conf->device_lock, flags); + /* In case raid10d snuck in to freeze_array */ + wake_up(&conf->wait_barrier); + if (do_sync) md_wakeup_thread(mddev->thread); @@ -1464,28 +1510,14 @@ static void raid10d(mddev_t *mddev) for (;;) { char b[BDEVNAME_SIZE]; - spin_lock_irqsave(&conf->device_lock, flags); - if (conf->pending_bio_list.head) { - bio = bio_list_get(&conf->pending_bio_list); - blk_remove_plug(mddev->queue); - spin_unlock_irqrestore(&conf->device_lock, flags); - /* flush any pending bitmap writes to disk before proceeding w/ I/O */ - bitmap_unplug(mddev->bitmap); - - while (bio) { /* submit pending writes */ - struct bio *next = bio->bi_next; - bio->bi_next = NULL; - generic_make_request(bio); - bio = next; - } - unplug = 1; - - continue; - } + unplug += flush_pending_writes(conf); - if (list_empty(head)) + spin_lock_irqsave(&conf->device_lock, flags); + if (list_empty(head)) { + spin_unlock_irqrestore(&conf->device_lock, flags); break; + } r10_bio = list_entry(head->prev, r10bio_t, retry_list); list_del(head->prev); conf->nr_queued--; @@ -1548,7 +1580,6 @@ static void raid10d(mddev_t *mddev) } } } - spin_unlock_irqrestore(&conf->device_lock, flags); if (unplug) unplug_slaves(mddev); } @@ -1787,6 +1818,8 @@ static sector_t sync_request(mddev_t *mddev, sector_t sector_nr, int *skipped, i if (j == conf->copies) { /* Cannot recover, so abort the recovery */ put_buf(r10_bio); + if (rb2) + atomic_dec(&rb2->remaining); r10_bio = rb2; if (!test_and_set_bit(MD_RECOVERY_ERR, &mddev->recovery)) printk(KERN_INFO "raid10: %s: insufficient working devices for recovery.\n", |