Btrfs: Less aggressive readahead on deletes

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

1 files changed, 11 insertions, 9 deletions

diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c
index 7f764455f26e..2b3ffa707eae 100644
--- a/fs/btrfs/ctree.c
+++ b/fs/btrfs/ctree.c
@@ -987,9 +987,10 @@ static int push_nodes_for_insert(struct btrfs_trans_handle *trans,
  * readahead one full node of leaves
  */
 static void reada_for_search(struct btrfs_root *root, struct btrfs_path *path,
-                             int level, int slot)
+                             int level, int slot, u64 objectid)
 {
         struct extent_buffer *node;
+        struct btrfs_disk_key disk_key;
         u32 nritems;
         u64 search;
         u64 lowest_read;
@@ -1031,6 +1032,11 @@ static void reada_for_search(struct btrfs_root *root, struct btrfs_path *path,
                         if (nr >= nritems)
                                 break;
                 }
+                if (path->reada < 0 && objectid) {
+                        btrfs_node_key(node, &disk_key, nr);
+                        if (btrfs_disk_key_objectid(&disk_key) != objectid)
+                                break;
+                }
                 search = btrfs_node_blockptr(node, nr);
                 if ((search >= lowest_read && search <= highest_read) ||
                     (search < lowest_read && lowest_read - search <= 32768) ||
@@ -1136,7 +1142,8 @@ again:
                         bytenr = btrfs_node_blockptr(b, slot);
                         ptr_gen = btrfs_node_ptr_generation(b, slot);
                         if (should_reada)
-                                reada_for_search(root, p, level, slot);
+                                reada_for_search(root, p, level, slot,
+                                                 key->objectid);
                         b = read_tree_block(root, bytenr,
                                             btrfs_level_size(root, level - 1));
                         if (ptr_gen != btrfs_header_generation(b)) {
@@ -2671,9 +2678,6 @@ int btrfs_prev_leaf(struct btrfs_root *root, struct btrfs_path *path)
                 if (next)
                         free_extent_buffer(next);
 
-                if (path->reada < 0)
-                        reada_for_search(root, path, level, slot);
-
                 next = read_tree_block(root, bytenr,
                                        btrfs_level_size(root, level - 1));
                 break;
@@ -2687,8 +2691,6 @@ int btrfs_prev_leaf(struct btrfs_root *root, struct btrfs_path *path)
                 path->slots[level] = 0;
                 if (!level)
                         break;
-                if (path->reada)
-                        reada_for_search(root, path, level, 0);
                 next = read_tree_block(root, btrfs_node_blockptr(next, 0),
                                        btrfs_level_size(root, level - 1));
         }
@@ -2726,7 +2728,7 @@ int btrfs_next_leaf(struct btrfs_root *root, struct btrfs_path *path)
                         free_extent_buffer(next);
 
                 if (path->reada)
-                        reada_for_search(root, path, level, slot);
+                        reada_for_search(root, path, level, slot, 0);
 
                 next = read_tree_block(root, bytenr,
                                        btrfs_level_size(root, level -1));
@@ -2742,7 +2744,7 @@ int btrfs_next_leaf(struct btrfs_root *root, struct btrfs_path *path)
                 if (!level)
                         break;
                 if (path->reada)
-                        reada_for_search(root, path, level, 0);
+                        reada_for_search(root, path, level, 0, 0);
                 next = read_tree_block(root, btrfs_node_blockptr(next, 0),
                                        btrfs_level_size(root, level - 1));
         }