If we're looking for a metadata item in the tree and the search fails with return value of 1, and the slot doesn't point to the first item in the leaf, check if the previous item in the leaf corresponds to an extent item for the same object id - if it does, then don't do another tree search to get it.
This optimization is already done by btrfs-progs. V2: updated commit message. Signed-off-by: Filipe David Borba Manana <fdman...@gmail.com> --- fs/btrfs/extent-tree.c | 21 +++++++++++++++++---- 1 file changed, 17 insertions(+), 4 deletions(-) diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c index 0236de7..4b19c88 100644 --- a/fs/btrfs/extent-tree.c +++ b/fs/btrfs/extent-tree.c @@ -771,10 +771,23 @@ again: goto out_free; if (ret > 0 && metadata && key.type == BTRFS_METADATA_ITEM_KEY) { - key.type = BTRFS_EXTENT_ITEM_KEY; - key.offset = root->leafsize; - btrfs_release_path(path); - goto again; + metadata = 0; + if (path->slots[0]) { + path->slots[0]--; + btrfs_item_key_to_cpu(path->nodes[0], &key, + path->slots[0]); + if (key.objectid == bytenr && + key.type == BTRFS_EXTENT_ITEM_KEY && + key.offset == root->leafsize) + ret = 0; + } + if (ret) { + key.objectid = bytenr; + key.type = BTRFS_EXTENT_ITEM_KEY; + key.offset = root->leafsize; + btrfs_release_path(path); + goto again; + } } if (ret == 0) { -- 1.7.9.5 -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html