1 files changed, 15 insertions, 18 deletions

diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index 980d6a3c342c..59c8daaacf0c 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -3328,15 +3328,14 @@ static int shrink_delalloc(struct btrfs_trans_handle *trans,
         u64 reserved;
         u64 max_reclaim;
         u64 reclaimed = 0;
-        int no_reclaim = 0;
         int pause = 1;
-        int ret;
+        int nr_pages = (2 * 1024 * 1024) >> PAGE_CACHE_SHIFT;
 
         block_rsv = &root->fs_info->delalloc_block_rsv;
         space_info = block_rsv->space_info;
-        spin_lock(&space_info->lock);
+
+        smp_mb();
         reserved = space_info->bytes_reserved;
-        spin_unlock(&space_info->lock);
 
         if (reserved == 0)
                 return 0;
@@ -3344,20 +3343,11 @@ static int shrink_delalloc(struct btrfs_trans_handle *trans,
         max_reclaim = min(reserved, to_reclaim);
 
         while (1) {
-                ret = btrfs_start_one_delalloc_inode(root, trans ? 1 : 0, sync);
-                if (!ret) {
-                        if (no_reclaim > 2)
-                                break;
-                        no_reclaim++;
-                        __set_current_state(TASK_INTERRUPTIBLE);
-                        schedule_timeout(pause);
-                        pause <<= 1;
-                        if (pause > HZ / 10)
-                                pause = HZ / 10;
-                } else {
-                        no_reclaim = 0;
-                        pause = 1;
-                }
+                /* have the flusher threads jump in and do some IO */
+                smp_mb();
+                nr_pages = min_t(unsigned long, nr_pages,
+                       root->fs_info->delalloc_bytes >> PAGE_CACHE_SHIFT);
+                writeback_inodes_sb_nr_if_idle(root->fs_info->sb, nr_pages);
 
                 spin_lock(&space_info->lock);
                 if (reserved > space_info->bytes_reserved)
@@ -3370,6 +3360,13 @@ static int shrink_delalloc(struct btrfs_trans_handle *trans,
 
                 if (trans && trans->transaction->blocked)
                         return -EAGAIN;
+
+                __set_current_state(TASK_INTERRUPTIBLE);
+                schedule_timeout(pause);
+                pause <<= 1;
+                if (pause > HZ / 10)
+                        pause = HZ / 10;
+
         }
         return reclaimed >= to_reclaim;
 }