From a13b8c5f2381495879e6facd3b3ada51c9e68194 Mon Sep 17 00:00:00 2001 From: Wendy Cheng Date: Mon, 20 Aug 2007 09:29:53 -0400 Subject: [PATCH] [GFS2] Reduce truncate IO traffic Current GFS2 setattr call unconditionally invokes do_shrink even the requested size and actual file size are equal. This has generated large amount of extra IOs found during NFS benchmark runs. This patch moves the relevant logic out of shrink code path. Since setattr is a system call, the time stamps update is still required. Signed-off-by: S. Wendy Cheng Signed-off-by: Steven Whitehouse --- fs/gfs2/bmap.c | 32 +++++++++++++++++++++++++++++++- 1 file changed, 31 insertions(+), 1 deletion(-) diff --git a/fs/gfs2/bmap.c b/fs/gfs2/bmap.c index cd805a66880d..9b8990444e6c 100644 --- a/fs/gfs2/bmap.c +++ b/fs/gfs2/bmap.c @@ -1085,6 +1085,33 @@ static int do_shrink(struct gfs2_inode *ip, u64 size) return error; } +static int do_touch(struct gfs2_inode *ip, u64 size) +{ + struct gfs2_sbd *sdp = GFS2_SB(&ip->i_inode); + struct buffer_head *dibh; + int error; + + error = gfs2_trans_begin(sdp, RES_DINODE, 0); + if (error) + return error; + + down_write(&ip->i_rw_mutex); + + error = gfs2_meta_inode_buffer(ip, &dibh); + if (error) + goto do_touch_out; + + ip->i_inode.i_mtime = ip->i_inode.i_ctime = CURRENT_TIME; + gfs2_trans_add_bh(ip->i_gl, dibh, 1); + gfs2_dinode_out(ip, dibh->b_data); + brelse(dibh); + +do_touch_out: + up_write(&ip->i_rw_mutex); + gfs2_trans_end(sdp); + return error; +} + /** * gfs2_truncatei - make a file a given size * @ip: the inode @@ -1105,8 +1132,11 @@ int gfs2_truncatei(struct gfs2_inode *ip, u64 size) if (size > ip->i_di.di_size) error = do_grow(ip, size); - else + else if (size < ip->i_di.di_size) error = do_shrink(ip, size); + else + /* update time stamps */ + error = do_touch(ip, size); return error; } -- 2.39.5