Commit 53362a05 authored by Jianpeng Ma's avatar Jianpeng Ma Committed by Jens Axboe
Browse files

fs/block-dev.c:fix performance regression in O_DIRECT writes to md block devices 



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: default avatarJianpeng Ma <majianpeng@gmail.com>
Reviewed-by: default avatarNeilBrown <neilb@suse.de>
Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent c6e66634

fs/block_dev.c

+3 −0
Original line number Diff line number Diff line
@@ -1578,10 +1578,12 @@ ssize_t blkdev_aio_write(struct kiocb *iocb, const struct iovec *iov, 
			 unsigned long nr_segs, loff_t pos)

{

	struct file *file = iocb->ki_filp;

	struct blk_plug plug;

	ssize_t ret;



	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);