From 1ef30be142d2cc60e2687ef267de864cf31be995 Mon Sep 17 00:00:00 2001 From: Josef Bacik Date: Tue, 5 Apr 2011 19:25:36 -0400 Subject: [PATCH] Btrfs: do not call btrfs_update_inode in endio if nothing changed In the DIO code we often don't update the i_disk_size because the i_size isn't updated until after the DIO is completed, so basically we are allocating a path, doing a search, and updating the inode item for no reason since nothing changed. btrfs_ordered_update_i_size will return 1 if it didn't update i_disk_size, so only run btrfs_update_inode if btrfs_ordered_update_i_size returns 0. Thanks, Signed-off-by: Josef Bacik --- fs/btrfs/inode.c | 15 ++++++++++----- 1 file changed, 10 insertions(+), 5 deletions(-) diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index da2680263d9f..4a238d676e5b 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -1769,9 +1769,12 @@ static int btrfs_finish_ordered_io(struct inode *inode, u64 start, u64 end) add_pending_csums(trans, inode, ordered_extent->file_offset, &ordered_extent->list); - btrfs_ordered_update_i_size(inode, 0, ordered_extent); - ret = btrfs_update_inode(trans, root, inode); - BUG_ON(ret); + ret = btrfs_ordered_update_i_size(inode, 0, ordered_extent); + if (!ret) { + ret = btrfs_update_inode(trans, root, inode); + BUG_ON(ret); + } + ret = 0; out: if (nolock) { if (trans) @@ -5865,8 +5868,10 @@ again: } add_pending_csums(trans, inode, ordered->file_offset, &ordered->list); - btrfs_ordered_update_i_size(inode, 0, ordered); - btrfs_update_inode(trans, root, inode); + ret = btrfs_ordered_update_i_size(inode, 0, ordered); + if (!ret) + btrfs_update_inode(trans, root, inode); + ret = 0; out_unlock: unlock_extent_cached(&BTRFS_I(inode)->io_tree, ordered->file_offset, ordered->file_offset + ordered->len - 1,