Btrfs: Make defrag check nodes against the progress key to prevent repeating work

Signed-off-by: Chris Mason <chris.mason@oracle.com>

2 files changed, 34 insertions, 25 deletions

diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c
index eef9c92f86d5..ea9b46699349 100644
--- a/fs/btrfs/ctree.c
+++ b/fs/btrfs/ctree.c
@@ -161,6 +161,31 @@ static int close_blocks(u64 blocknr, u64 other, u32 blocksize)
         return 0;
 }
 
+/*
+ * compare two keys in a memcmp fashion
+ */
+static int comp_keys(struct btrfs_disk_key *disk, struct btrfs_key *k2)
+{
+        struct btrfs_key k1;
+
+        btrfs_disk_key_to_cpu(&k1, disk);
+
+        if (k1.objectid > k2->objectid)
+                return 1;
+        if (k1.objectid < k2->objectid)
+                return -1;
+        if (k1.type > k2->type)
+                return 1;
+        if (k1.type < k2->type)
+                return -1;
+        if (k1.offset > k2->offset)
+                return 1;
+        if (k1.offset < k2->offset)
+                return -1;
+        return 0;
+}
+
+
 int btrfs_realloc_node(struct btrfs_trans_handle *trans,
                        struct btrfs_root *root, struct extent_buffer *parent,
                        int start_slot, int cache_only, u64 *last_ret,
@@ -179,6 +204,8 @@ int btrfs_realloc_node(struct btrfs_trans_handle *trans,
         int parent_level;
         int uptodate;
         u32 blocksize;
+        int progress_passed = 0;
+        struct btrfs_disk_key disk_key;
 
         parent_level = btrfs_header_level(parent);
         if (cache_only && parent_level != 1)
@@ -213,6 +240,11 @@ int btrfs_realloc_node(struct btrfs_trans_handle *trans,
                                         &parent->map_start, &parent->map_len,
                                         KM_USER1);
                 }
+                btrfs_node_key(parent, &disk_key, i);
+                if (!progress_passed && comp_keys(&disk_key, progress) < 0)
+                        continue;
+
+                progress_passed = 1;
                 blocknr = btrfs_node_blockptr(parent, i);
                 if (last_block == 0)
                         last_block = blocknr;
@@ -292,30 +324,6 @@ static inline unsigned int leaf_data_end(struct btrfs_root *root,
         return btrfs_item_offset_nr(leaf, nr - 1);
 }
 
-/*
- * compare two keys in a memcmp fashion
- */
-static int comp_keys(struct btrfs_disk_key *disk, struct btrfs_key *k2)
-{
-        struct btrfs_key k1;
-
-        btrfs_disk_key_to_cpu(&k1, disk);
-
-        if (k1.objectid > k2->objectid)
-                return 1;
-        if (k1.objectid < k2->objectid)
-                return -1;
-        if (k1.type > k2->type)
-                return 1;
-        if (k1.type < k2->type)
-                return -1;
-        if (k1.offset > k2->offset)
-                return 1;
-        if (k1.offset < k2->offset)
-                return -1;
-        return 0;
-}
-
 static int check_node(struct btrfs_root *root, struct btrfs_path *path,
                       int level)
 {
diff --git a/fs/btrfs/tree-defrag.c b/fs/btrfs/tree-defrag.c
index 65ef12351566..6ef1ba5f9c2f 100644
--- a/fs/btrfs/tree-defrag.c
+++ b/fs/btrfs/tree-defrag.c
@@ -227,7 +227,8 @@ int btrfs_defrag_leaves(struct btrfs_trans_handle *trans,
                         break;
                 if (wret < 0)
                         ret = wret;
-                ret = -EAGAIN;
+                else
+                        ret = -EAGAIN;
                 break;
         }
         for (i = 0; i <= orig_level; i++) {