From patchwork Mon Jun 6 23:43:41 2011 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Subject: PATCH 1/2 v2] EXT4: Skip un-needed extent lookup Date: Mon, 06 Jun 2011 13:43:41 -0000 From: Allison Henderson X-Patchwork-Id: 99061 Message-Id: <4DED662D.2090109@vnet.ibm.com> To: Ext4 Developers List This patch optimizes the punch hole operation by skipping the tree walking code that is used by truncate. Since punch hole is done through map blocks, the path to the extent is already known in this function, so we do not need to look it up again. Signed-off-by: Allison Henderson --- :100644 100644 5199bac... ecaa767... M fs/ext4/extents.c fs/ext4/extents.c | 23 +++++++++++++++++++++-- 1 files changed, 21 insertions(+), 2 deletions(-) diff --git a/fs/ext4/extents.c b/fs/ext4/extents.c index 5199bac..ecaa767 100644 --- a/fs/ext4/extents.c +++ b/fs/ext4/extents.c @@ -3497,8 +3497,27 @@ int ext4_ext_map_blocks(handle_t *handle, struct inode *inode, ext4_ext_mark_uninitialized(ex); - err = ext4_ext_remove_space(inode, map->m_lblk, - map->m_lblk + punched_out); + ext4_ext_invalidate_cache(inode); + + err = ext4_ext_rm_leaf(handle, inode, path, + map->m_lblk, map->m_lblk + punched_out); + + if (!err && path->p_hdr->eh_entries == 0) { + /* + * Punch hole freed all of this sub tree, + * so we need to correct eh_depth + */ + err = ext4_ext_get_access(handle, inode, path); + if (err == 0) { + ext_inode_hdr(inode)->eh_depth = 0; + ext_inode_hdr(inode)->eh_max = + cpu_to_le16(ext4_ext_space_root( + inode, 0)); + + err = ext4_ext_dirty( + handle, inode, path); + } + } goto out2; }