bcache: wait for buckets when allocating new btree root

Tested: - sometimes bcache_tier test would hang on startup with a failure to allocate the btree root -- no longer seeing this Signed-off-by: Kent Overstreet <kmo@daterainc.com>

bcache: wait for buckets when allocating new btree root
Tested: - sometimes bcache_tier test would hang on startup with a failure to allocate the btree root -- no longer seeing this Signed-off-by: Kent Overstreet <kmo@daterainc.com>
Slava Pestov · Kent Overstreet
1 parent a664d0f05a
Showing 3 changed files with 12 additions and 5 deletions Side-by-side Diff
drivers/md/bcache/btree.c
drivers/md/bcache/btree.h
drivers/md/bcache/super.c
@@ -1060,15 +1060,15 @@
 	mutex_unlock(&b->c->bucket_lock);
 }
  
-struct btree *bch_btree_node_alloc(struct cache_set *c, struct btree_op *op,
-				   int level)
+struct btree *__bch_btree_node_alloc(struct cache_set *c, struct btree_op *op,
+				     int level, bool wait)
 {
 	BKEY_PADDED(key) k;
 	struct btree *b = ERR_PTR(-EAGAIN);
  
 	mutex_lock(&c->bucket_lock);
 retry:
-	if (__bch_bucket_alloc_set(c, RESERVE_BTREE, &k.key, 1, op != NULL))
+	if (__bch_bucket_alloc_set(c, RESERVE_BTREE, &k.key, 1, wait))
 		goto err;
  
 	bkey_put(c, &k.key);
@@ -1098,6 +1098,12 @@
  
 	trace_bcache_btree_node_alloc_fail(b);
 	return b;
+}
+
+static struct btree *bch_btree_node_alloc(struct cache_set *c,
+					  struct btree_op *op, int level)
+{
+	return __bch_btree_node_alloc(c, op, level, op != NULL);
 }
  
 static struct btree *btree_node_alloc_replacement(struct btree *b,
@@ -242,7 +242,8 @@
 void bch_btree_node_write(struct btree *, struct closure *);
  
 void bch_btree_set_root(struct btree *);
-struct btree *bch_btree_node_alloc(struct cache_set *, struct btree_op *, int);
+struct btree *__bch_btree_node_alloc(struct cache_set *, struct btree_op *,
+				     int, bool);
 struct btree *bch_btree_node_get(struct cache_set *, struct btree_op *,
 				 struct bkey *, int, bool);
  
@@ -1669,7 +1669,7 @@
 			goto err;
  
 		err = "cannot allocate new btree root";
-		c->root = bch_btree_node_alloc(c, NULL, 0);
+		c->root = __bch_btree_node_alloc(c, NULL, 0, true);
 		if (IS_ERR_OR_NULL(c->root))
 			goto err;
...	...	@@ -1060,15 +1060,15 @@
1060	1060	mutex_unlock(&b->c->bucket_lock);
1061	1061	}
1062	1062
1063		-struct btree bch_btree_node_alloc(struct cache_set c, struct btree_op *op,
1064		- int level)
	1063	+struct btree __bch_btree_node_alloc(struct cache_set c, struct btree_op *op,
	1064	+ int level, bool wait)
1065	1065	{
1066	1066	BKEY_PADDED(key) k;
1067	1067	struct btree *b = ERR_PTR(-EAGAIN);
1068	1068
1069	1069	mutex_lock(&c->bucket_lock);
1070	1070	retry:
1071		- if (__bch_bucket_alloc_set(c, RESERVE_BTREE, &k.key, 1, op != NULL))
	1071	+ if (__bch_bucket_alloc_set(c, RESERVE_BTREE, &k.key, 1, wait))
1072	1072	goto err;
1073	1073
1074	1074	bkey_put(c, &k.key);
...	...	@@ -1098,6 +1098,12 @@
1098	1098
1099	1099	trace_bcache_btree_node_alloc_fail(b);
1100	1100	return b;
	1101	+}
	1102	+
	1103	+static struct btree bch_btree_node_alloc(struct cache_set c,
	1104	+ struct btree_op *op, int level)
	1105	+{
	1106	+ return __bch_btree_node_alloc(c, op, level, op != NULL);
1101	1107	}
1102	1108
1103	1109	static struct btree btree_node_alloc_replacement(struct btree b,
...	...	@@ -242,7 +242,8 @@
242	242	void bch_btree_node_write(struct btree , struct closure );
243	243
244	244	void bch_btree_set_root(struct btree *);
245		-struct btree bch_btree_node_alloc(struct cache_set , struct btree_op *, int);
	245	+struct btree __bch_btree_node_alloc(struct cache_set , struct btree_op *,
	246	+ int, bool);
246	247	struct btree bch_btree_node_get(struct cache_set , struct btree_op *,
247	248	struct bkey *, int, bool);
248	249
...	...	@@ -1669,7 +1669,7 @@
1669	1669	goto err;
1670	1670
1671	1671	err = "cannot allocate new btree root";
1672		- c->root = bch_btree_node_alloc(c, NULL, 0);
	1672	+ c->root = __bch_btree_node_alloc(c, NULL, 0, true);
1673	1673	if (IS_ERR_OR_NULL(c->root))
1674	1674	goto err;
1675	1675