From 20341fd51e03d7fc61bfe125b3ab28c4fbebf637 Mon Sep 17 00:00:00 2001
From: Josef Bacik <josef@redhat.com>
Date: Tue, 6 Oct 2009 10:04:28 -0400
Subject: [PATCH] --- yaml --- r: 167253 b: refs/heads/master c:
 1cdda9b81ac0e6ee986f034fa02f221679e1c11a h: refs/heads/master i:   167251:
 bd7351d77ad09ddfe8a94c48df7a58c9477d4115 v: v3

---
 [refs]                       |  2 +-
 trunk/fs/btrfs/extent-tree.c | 23 +++++++++++++++++------
 2 files changed, 18 insertions(+), 7 deletions(-)

diff --git a/[refs] b/[refs]
index 2e7fb4f64a08..956c0a4b80d3 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 61d92c328c16419fc96dc50dd16f8b8c695409ec
+refs/heads/master: 1cdda9b81ac0e6ee986f034fa02f221679e1c11a
diff --git a/trunk/fs/btrfs/extent-tree.c b/trunk/fs/btrfs/extent-tree.c
index d119c0388af1..2f82fabd7011 100644
--- a/trunk/fs/btrfs/extent-tree.c
+++ b/trunk/fs/btrfs/extent-tree.c
@@ -4028,6 +4028,7 @@ static noinline int find_free_extent(struct btrfs_trans_handle *trans,
 	int loop = 0;
 	bool found_uncached_bg = false;
 	bool failed_cluster_refill = false;
+	bool failed_alloc = false;
 
 	WARN_ON(num_bytes < root->sectorsize);
 	btrfs_set_key_type(ins, BTRFS_EXTENT_ITEM_KEY);
@@ -4232,14 +4233,23 @@ static noinline int find_free_extent(struct btrfs_trans_handle *trans,
 
 		offset = btrfs_find_space_for_alloc(block_group, search_start,
 						    num_bytes, empty_size);
-		if (!offset && (cached || (!cached &&
-					   loop == LOOP_CACHING_NOWAIT))) {
-			goto loop;
-		} else if (!offset && (!cached &&
-				       loop > LOOP_CACHING_NOWAIT)) {
+		/*
+		 * If we didn't find a chunk, and we haven't failed on this
+		 * block group before, and this block group is in the middle of
+		 * caching and we are ok with waiting, then go ahead and wait
+		 * for progress to be made, and set failed_alloc to true.
+		 *
+		 * If failed_alloc is true then we've already waited on this
+		 * block group once and should move on to the next block group.
+		 */
+		if (!offset && !failed_alloc && !cached &&
+		    loop > LOOP_CACHING_NOWAIT) {
 			wait_block_group_cache_progress(block_group,
-					num_bytes + empty_size);
+						num_bytes + empty_size);
+			failed_alloc = true;
 			goto have_block_group;
+		} else if (!offset) {
+			goto loop;
 		}
 checks:
 		search_start = stripe_align(root, offset);
@@ -4287,6 +4297,7 @@ static noinline int find_free_extent(struct btrfs_trans_handle *trans,
 		break;
 loop:
 		failed_cluster_refill = false;
+		failed_alloc = false;
 		btrfs_put_block_group(block_group);
 	}
 	up_read(&space_info->groups_sem);