diff options
Diffstat (limited to 'drivers/md/raid5.c')
| -rw-r--r-- | drivers/md/raid5.c | 34 |
1 files changed, 27 insertions, 7 deletions
diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c index 47413f7f02b9..a90d5876fdad 100644 --- a/drivers/md/raid5.c +++ b/drivers/md/raid5.c @@ -2153,6 +2153,9 @@ static int resize_stripes(struct r5conf *conf, int newsize) if (!sc) return -ENOMEM; + /* Need to ensure auto-resizing doesn't interfere */ + mutex_lock(&conf->cache_size_mutex); + for (i = conf->max_nr_stripes; i; i--) { nsh = alloc_stripe(sc, GFP_KERNEL); if (!nsh) @@ -2169,6 +2172,7 @@ static int resize_stripes(struct r5conf *conf, int newsize) kmem_cache_free(sc, nsh); } kmem_cache_destroy(sc); + mutex_unlock(&conf->cache_size_mutex); return -ENOMEM; } /* Step 2 - Must use GFP_NOIO now. @@ -2215,6 +2219,7 @@ static int resize_stripes(struct r5conf *conf, int newsize) } else err = -ENOMEM; + mutex_unlock(&conf->cache_size_mutex); /* Step 4, return new stripes to service */ while(!list_empty(&newstripes)) { nsh = list_entry(newstripes.next, struct stripe_head, lru); @@ -2242,7 +2247,7 @@ static int resize_stripes(struct r5conf *conf, int newsize) static int drop_one_stripe(struct r5conf *conf) { struct stripe_head *sh; - int hash = (conf->max_nr_stripes - 1) % NR_STRIPE_HASH_LOCKS; + int hash = (conf->max_nr_stripes - 1) & STRIPE_HASH_LOCKS_MASK; spin_lock_irq(conf->hash_locks + hash); sh = get_free_stripe(conf, hash); @@ -5848,12 +5853,14 @@ static void raid5d(struct md_thread *thread) pr_debug("%d stripes handled\n", handled); spin_unlock_irq(&conf->device_lock); - if (test_and_clear_bit(R5_ALLOC_MORE, &conf->cache_state)) { + if (test_and_clear_bit(R5_ALLOC_MORE, &conf->cache_state) && + mutex_trylock(&conf->cache_size_mutex)) { grow_one_stripe(conf, __GFP_NOWARN); /* Set flag even if allocation failed. This helps * slow down allocation requests when mem is short */ set_bit(R5_DID_ALLOC, &conf->cache_state); + mutex_unlock(&conf->cache_size_mutex); } async_tx_issue_pending_all(); @@ -5885,18 +5892,22 @@ raid5_set_cache_size(struct mddev *mddev, int size) return -EINVAL; conf->min_nr_stripes = size; + mutex_lock(&conf->cache_size_mutex); while (size < conf->max_nr_stripes && drop_one_stripe(conf)) ; + mutex_unlock(&conf->cache_size_mutex); err = md_allow_write(mddev); if (err) return err; + mutex_lock(&conf->cache_size_mutex); while (size > conf->max_nr_stripes) if (!grow_one_stripe(conf, GFP_KERNEL)) break; + mutex_unlock(&conf->cache_size_mutex); return 0; } @@ -6363,11 +6374,19 @@ static unsigned long raid5_cache_scan(struct shrinker *shrink, struct shrink_control *sc) { struct r5conf *conf = container_of(shrink, struct r5conf, shrinker); - int ret = 0; - while (ret < sc->nr_to_scan) { - if (drop_one_stripe(conf) == 0) - return SHRINK_STOP; - ret++; + unsigned long ret = SHRINK_STOP; + + if (mutex_trylock(&conf->cache_size_mutex)) { + ret= 0; + while (ret < sc->nr_to_scan && + conf->max_nr_stripes > conf->min_nr_stripes) { + if (drop_one_stripe(conf) == 0) { + ret = SHRINK_STOP; + break; + } + ret++; + } + mutex_unlock(&conf->cache_size_mutex); } return ret; } @@ -6436,6 +6455,7 @@ static struct r5conf *setup_conf(struct mddev *mddev) goto abort; spin_lock_init(&conf->device_lock); seqcount_init(&conf->gen_lock); + mutex_init(&conf->cache_size_mutex); init_waitqueue_head(&conf->wait_for_stripe); init_waitqueue_head(&conf->wait_for_overlap); INIT_LIST_HEAD(&conf->handle_list); |