From mboxrd@z Thu Jan 1 00:00:00 1970 From: Li Zefan Subject: Re: [PATCH] Btrfs: check free space in block group before searching for a cluster Date: Mon, 21 Mar 2011 10:39:00 +0800 Message-ID: <4D86BA44.1040004@cn.fujitsu.com> References: <1300475786-1836-1-git-send-email-josef@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Cc: linux-btrfs@vger.kernel.org To: Josef Bacik Return-path: In-Reply-To: <1300475786-1836-1-git-send-email-josef@redhat.com> List-ID: Josef Bacik wrote: > The free space cluster stuff is heavy duty, so there is no sense in going > through the entire song and dance if there isn't enough space in the block group > to begin with. Thanks, > > Signed-off-by: Josef Bacik Reviewed-by: Li Zefan > --- > fs/btrfs/free-space-cache.c | 10 ++++++++++ > 1 files changed, 10 insertions(+), 0 deletions(-) > > diff --git a/fs/btrfs/free-space-cache.c b/fs/btrfs/free-space-cache.c > index 0282033..f631df8 100644 > --- a/fs/btrfs/free-space-cache.c > +++ b/fs/btrfs/free-space-cache.c > @@ -1999,6 +1999,16 @@ int btrfs_find_space_cluster(struct btrfs_trans_handle *trans, > min_bytes = max(bytes, (bytes + empty_size) >> 2); > > spin_lock(&block_group->tree_lock); > + > + /* > + * If we know we don't have enough space to make a cluster don't even > + * bother doing all the work to try and find one. > + */ > + if (block_group->free_space < min_bytes) { > + spin_unlock(&block_group->tree_lock); > + return -ENOSPC; > + } > + > spin_lock(&cluster->lock); > > /* someone already found a cluster, hooray */