From: Filipe Manana Date: Mon, 4 Aug 2014 18:37:21 +0000 (+0100) Subject: Btrfs: make btrfs_search_forward return with nodes unlocked X-Git-Tag: fixes-against-v3.18-rc2~120^2~77 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=f98de9b9c07485f7e21edfd5b2b20c89d662af3c;p=pandora-kernel.git Btrfs: make btrfs_search_forward return with nodes unlocked None of the uses of btrfs_search_forward() need to have the path nodes (level >= 1) read locked, only the leaf needs to be locked while the caller processes it. Therefore make it return a path with all nodes unlocked, except for the leaf. This change is motivated by the observation that during a file fsync we repeatdly call btrfs_search_forward() and process the returned leaf while upper nodes of the returned path (level >= 1) are read locked, which unnecessarily blocks other tasks that want to write to the same fs/subvol btree. Therefore instead of modifying the fsync code to unlock all nodes with level >= 1 immediately after calling btrfs_search_forward(), change btrfs_search_forward() to do it, so that it benefits all callers. Signed-off-by: Filipe Manana Signed-off-by: Chris Mason --- Reading git-diff-tree failed