1 files changed, 18 insertions, 10 deletions

diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index b8c6541c33f..0d73a53c676 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -2116,6 +2116,7 @@ static int noinline find_free_extent(struct btrfs_trans_handle *trans,
         struct btrfs_root * root = orig_root->fs_info->extent_root;
         u64 total_needed = num_bytes;
         u64 *last_ptr = NULL;
+        u64 last_wanted = 0;
         struct btrfs_block_group_cache *block_group = NULL;
         int chunk_alloc_done = 0;
         int empty_cluster = 2 * 1024 * 1024;
@@ -2134,22 +2135,28 @@ static int noinline find_free_extent(struct btrfs_trans_handle *trans,
 
         if (data & BTRFS_BLOCK_GROUP_METADATA) {
                 last_ptr = &root->fs_info->last_alloc;
-                empty_cluster = 256 * 1024;
+                empty_cluster = 64 * 1024;
         }
 
         if ((data & BTRFS_BLOCK_GROUP_DATA) && btrfs_test_opt(root, SSD))
                 last_ptr = &root->fs_info->last_data_alloc;
 
         if (last_ptr) {
-                if (*last_ptr)
+                if (*last_ptr) {
                         hint_byte = *last_ptr;
-                else
+                        last_wanted = *last_ptr;
+                } else
                         empty_size += empty_cluster;
+        } else {
+                empty_cluster = 0;
         }
         search_start = max(search_start, first_logical_byte(root, 0));
         search_start = max(search_start, hint_byte);
         total_needed += empty_size;
 
+        if (search_start != last_wanted)
+                last_wanted = 0;
+
         block_group = btrfs_lookup_block_group(root->fs_info, search_start);
         if (!block_group)
                 block_group = btrfs_lookup_first_block_group(root->fs_info,
@@ -2195,9 +2202,9 @@ static int noinline find_free_extent(struct btrfs_trans_handle *trans,
                         if (search_start + num_bytes > end)
                                 goto new_group;
 
-                        if (last_ptr && *last_ptr && search_start != *last_ptr) {
+                        if (last_wanted && search_start != last_wanted) {
                                 total_needed += empty_cluster;
-                                *last_ptr = 0;
+                                last_wanted = 0;
                                 /*
                                  * if search_start is still in this block group
                                  * then we just re-search this block group
@@ -2223,6 +2230,7 @@ static int noinline find_free_extent(struct btrfs_trans_handle *trans,
                                 if (search_start >= start &&
                                     search_start < end) {
                                         mutex_unlock(&block_group->alloc_mutex);
+                                        last_wanted = 0;
                                         continue;
                                 }
 
@@ -2240,6 +2248,11 @@ static int noinline find_free_extent(struct btrfs_trans_handle *trans,
                         break;
                 }
 new_group:
+                last_wanted = 0;
+                if (loop > 0) {
+                        total_needed -= empty_cluster;
+                        empty_cluster = 0;
+                }
                 mutex_unlock(&block_group->alloc_mutex);
                 /*
                  * Here's how this works.
@@ -2256,11 +2269,6 @@ new_group:
                 if (loop == 0) {
                         head = &space_info->block_groups;
                         cur = head->next;
-
-                        if (last_ptr && *last_ptr) {
-                                total_needed += empty_cluster;
-                                *last_ptr = 0;
-                        }
                         loop++;
                 } else if (loop == 1 && cur == head) {
                         if (allowed_chunk_alloc && !chunk_alloc_done) {