From fc0063c4474599b7a066ba76b90902abe21bc675 Mon Sep 17 00:00:00 2001 From: Christoph Hellwig Date: Tue, 23 Aug 2011 08:28:11 +0000 Subject: [PATCH] xfs: reduce ioend latency There is no reason to queue up ioends for processing in user context unless we actually need it. Just complete ioends that do not convert unwritten extents or need a size update from the end_io context. Signed-off-by: Christoph Hellwig Reviewed-by: Dave Chinner Signed-off-by: Alex Elder --- fs/xfs/xfs_aops.c | 16 +++++++++++++++- 1 file changed, 15 insertions(+), 1 deletion(-) diff --git a/fs/xfs/xfs_aops.c b/fs/xfs/xfs_aops.c index 10660c364105..e1ff0770784e 100644 --- a/fs/xfs/xfs_aops.c +++ b/fs/xfs/xfs_aops.c @@ -149,6 +149,15 @@ xfs_ioend_new_eof( return isize > ip->i_d.di_size ? isize : 0; } +/* + * Fast and loose check if this write could update the on-disk inode size. + */ +static inline bool xfs_ioend_is_append(struct xfs_ioend *ioend) +{ + return ioend->io_offset + ioend->io_size > + XFS_I(ioend->io_inode)->i_d.di_size; +} + /* * Update on-disk file size now that data has been written to disk. The * current in-memory file size is i_size. If a write is beyond eof i_new_size @@ -186,6 +195,9 @@ xfs_setfilesize( /* * Schedule IO completion handling on the final put of an ioend. + * + * If there is no work to do we might as well call it a day and free the + * ioend right now. */ STATIC void xfs_finish_ioend( @@ -194,8 +206,10 @@ xfs_finish_ioend( if (atomic_dec_and_test(&ioend->io_remaining)) { if (ioend->io_type == IO_UNWRITTEN) queue_work(xfsconvertd_workqueue, &ioend->io_work); - else + else if (xfs_ioend_is_append(ioend)) queue_work(xfsdatad_workqueue, &ioend->io_work); + else + xfs_destroy_ioend(ioend); } } -- 2.20.1