[PATCH 1/2 V1] [PATCH] fs/block-dev.c:fix performance regression in O_DIRECT writes to md block devices
From: majianpeng <hidden>
Date: 2012-07-16 06:21:03
Also in:
linux-fsdevel
Subsystem:
filesystems (vfs and infrastructure), the rest · Maintainers:
Alexander Viro, Christian Brauner, Linus Torvalds
For regular file, write operaion used blk_plug function.But for block file,write operation did not use blk_plug. This patch is also for write-cache mode for block-device. Signed-off-by: Jianpeng Ma <redacted> --- fs/block_dev.c | 3 +++ 1 files changed, 3 insertions(+), 0 deletions(-)
diff --git a/fs/block_dev.c b/fs/block_dev.c
index c2bbe1f..cf10778 100644
--- a/fs/block_dev.c
+++ b/fs/block_dev.c@@ -1579,9 +1579,11 @@ ssize_t blkdev_aio_write(struct kiocb *iocb, const struct iovec *iov, { struct file *file = iocb->ki_filp; ssize_t ret; + struct blk_plug plug; BUG_ON(iocb->ki_pos != pos); + blk_start_plug(&plug); ret = __generic_file_aio_write(iocb, iov, nr_segs, &iocb->ki_pos); if (ret > 0 || ret == -EIOCBQUEUED) { ssize_t err;
@@ -1590,6 +1592,7 @@ ssize_t blkdev_aio_write(struct kiocb *iocb, const struct iovec *iov, if (err < 0 && ret > 0) ret = err; } + blk_finish_plug(&plug); return ret; } EXPORT_SYMBOL_GPL(blkdev_aio_write);
--
1.7.5.4