Linux-libre 4.2-gnu

1 files changed, 60 insertions, 24 deletions

diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c
index b6793d2e0..f757023fc 100644
--- a/drivers/md/raid5.c
+++ b/drivers/md/raid5.c
@@ -344,7 +344,8 @@ static void release_inactive_stripe_list(struct r5conf *conf,
 					 int hash)
 {
 	int size;
-	bool do_wakeup = false;
+	unsigned long do_wakeup = 0;
+	int i = 0;
 	unsigned long flags;
 
 	if (hash == NR_STRIPE_HASH_LOCKS) {
@@ -365,15 +366,21 @@ static void release_inactive_stripe_list(struct r5conf *conf,
 			    !list_empty(list))
 				atomic_dec(&conf->empty_inactive_list_nr);
 			list_splice_tail_init(list, conf->inactive_list + hash);
-			do_wakeup = true;
+			do_wakeup |= 1 << hash;
 			spin_unlock_irqrestore(conf->hash_locks + hash, flags);
 		}
 		size--;
 		hash--;
 	}
 
+	for (i = 0; i < NR_STRIPE_HASH_LOCKS; i++) {
+		if (do_wakeup & (1 << i))
+			wake_up(&conf->wait_for_stripe[i]);
+	}
+
 	if (do_wakeup) {
-		wake_up(&conf->wait_for_stripe);
+		if (atomic_read(&conf->active_stripes) == 0)
+			wake_up(&conf->wait_for_quiescent);
 		if (conf->retry_read_aligned)
 			md_wakeup_thread(conf->mddev->thread);
 	}
@@ -667,15 +674,15 @@ get_active_stripe(struct r5conf *conf, sector_t sector,
 	spin_lock_irq(conf->hash_locks + hash);
 
 	do {
-		wait_event_lock_irq(conf->wait_for_stripe,
+		wait_event_lock_irq(conf->wait_for_quiescent,
 				    conf->quiesce == 0 || noquiesce,
 				    *(conf->hash_locks + hash));
 		sh = __find_stripe(conf, sector, conf->generation - previous);
 		if (!sh) {
 			if (!test_bit(R5_INACTIVE_BLOCKED, &conf->cache_state)) {
 				sh = get_free_stripe(conf, hash);
-				if (!sh && llist_empty(&conf->released_stripes) &&
-				    !test_bit(R5_DID_ALLOC, &conf->cache_state))
+				if (!sh && !test_bit(R5_DID_ALLOC,
+						     &conf->cache_state))
 					set_bit(R5_ALLOC_MORE,
 						&conf->cache_state);
 			}
@@ -684,14 +691,15 @@ get_active_stripe(struct r5conf *conf, sector_t sector,
 			if (!sh) {
 				set_bit(R5_INACTIVE_BLOCKED,
 					&conf->cache_state);
-				wait_event_lock_irq(
-					conf->wait_for_stripe,
+				wait_event_exclusive_cmd(
+					conf->wait_for_stripe[hash],
 					!list_empty(conf->inactive_list + hash) &&
 					(atomic_read(&conf->active_stripes)
 					 < (conf->max_nr_stripes * 3 / 4)
 					 || !test_bit(R5_INACTIVE_BLOCKED,
 						      &conf->cache_state)),
-					*(conf->hash_locks + hash));
+					spin_unlock_irq(conf->hash_locks + hash),
+					spin_lock_irq(conf->hash_locks + hash));
 				clear_bit(R5_INACTIVE_BLOCKED,
 					  &conf->cache_state);
 			} else {
@@ -716,6 +724,9 @@ get_active_stripe(struct r5conf *conf, sector_t sector,
 		}
 	} while (sh == NULL);
 
+	if (!list_empty(conf->inactive_list + hash))
+		wake_up(&conf->wait_for_stripe[hash]);
+
 	spin_unlock_irq(conf->hash_locks + hash);
 	return sh;
 }
@@ -2151,6 +2162,9 @@ 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)
@@ -2167,6 +2181,7 @@ 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.
@@ -2177,7 +2192,7 @@ static int resize_stripes(struct r5conf *conf, int newsize)
 	cnt = 0;
 	list_for_each_entry(nsh, &newstripes, lru) {
 		lock_device_hash_lock(conf, hash);
-		wait_event_cmd(conf->wait_for_stripe,
+		wait_event_exclusive_cmd(conf->wait_for_stripe[hash],
 				    !list_empty(conf->inactive_list + hash),
 				    unlock_device_hash_lock(conf, hash),
 				    lock_device_hash_lock(conf, hash));
@@ -2213,6 +2228,7 @@ 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);
@@ -2240,7 +2256,7 @@ 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);
@@ -4050,8 +4066,10 @@ static void analyse_stripe(struct stripe_head *sh, struct stripe_head_state *s)
 				 &first_bad, &bad_sectors))
 			set_bit(R5_ReadRepl, &dev->flags);
 		else {
-			if (rdev)
+			if (rdev && !test_bit(Faulty, &rdev->flags))
 				set_bit(R5_NeedReplace, &dev->flags);
+			else
+				clear_bit(R5_NeedReplace, &dev->flags);
 			rdev = rcu_dereference(conf->disks[i].rdev);
 			clear_bit(R5_ReadRepl, &dev->flags);
 		}
@@ -4760,7 +4778,7 @@ static void raid5_align_endio(struct bio *bi, int error)
 					 raid_bi, 0);
 		bio_endio(raid_bi, 0);
 		if (atomic_dec_and_test(&conf->active_aligned_reads))
-			wake_up(&conf->wait_for_stripe);
+			wake_up(&conf->wait_for_quiescent);
 		return;
 	}
 
@@ -4855,7 +4873,7 @@ static int chunk_aligned_read(struct mddev *mddev, struct bio * raid_bio)
 		align_bi->bi_iter.bi_sector += rdev->data_offset;
 
 		spin_lock_irq(&conf->device_lock);
-		wait_event_lock_irq(conf->wait_for_stripe,
+		wait_event_lock_irq(conf->wait_for_quiescent,
 				    conf->quiesce == 0,
 				    conf->device_lock);
 		atomic_inc(&conf->active_aligned_reads);
@@ -5699,7 +5717,7 @@ static int  retry_aligned_read(struct r5conf *conf, struct bio *raid_bio)
 		bio_endio(raid_bio, 0);
 	}
 	if (atomic_dec_and_test(&conf->active_aligned_reads))
-		wake_up(&conf->wait_for_stripe);
+		wake_up(&conf->wait_for_quiescent);
 	return handled;
 }
 
@@ -5846,12 +5864,14 @@ 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();
@@ -5883,18 +5903,22 @@ 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;
 }
@@ -6360,11 +6384,19 @@ 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;
 }
@@ -6433,7 +6465,11 @@ static struct r5conf *setup_conf(struct mddev *mddev)
 		goto abort;
 	spin_lock_init(&conf->device_lock);
 	seqcount_init(&conf->gen_lock);
-	init_waitqueue_head(&conf->wait_for_stripe);
+	mutex_init(&conf->cache_size_mutex);
+	init_waitqueue_head(&conf->wait_for_quiescent);
+	for (i = 0; i < NR_STRIPE_HASH_LOCKS; i++) {
+		init_waitqueue_head(&conf->wait_for_stripe[i]);
+	}
 	init_waitqueue_head(&conf->wait_for_overlap);
 	INIT_LIST_HEAD(&conf->handle_list);
 	INIT_LIST_HEAD(&conf->hold_list);
@@ -7466,7 +7502,7 @@ static void raid5_quiesce(struct mddev *mddev, int state)
 		 * active stripes can drain
 		 */
 		conf->quiesce = 2;
-		wait_event_cmd(conf->wait_for_stripe,
+		wait_event_cmd(conf->wait_for_quiescent,
 				    atomic_read(&conf->active_stripes) == 0 &&
 				    atomic_read(&conf->active_aligned_reads) == 0,
 				    unlock_all_device_hash_locks_irq(conf),
@@ -7480,7 +7516,7 @@ static void raid5_quiesce(struct mddev *mddev, int state)
 	case 0: /* re-enable writes */
 		lock_all_device_hash_locks_irq(conf);
 		conf->quiesce = 0;
-		wake_up(&conf->wait_for_stripe);
+		wake_up(&conf->wait_for_quiescent);
 		wake_up(&conf->wait_for_overlap);
 		unlock_all_device_hash_locks_irq(conf);
 		break;