Commit 1af60fbd authored by Jeff Moyer's avatar Jeff Moyer Committed by Jens Axboe
Browse files

block: get rid of the WRITE_ODIRECT flag 



Hi,

The WRITE_ODIRECT flag is only used in one place, and that code path
happens to also call blk_run_address_space.  The introduction of this
flag, then, could result in the device being unplugged twice for every
I/O.

Further, with the batching changes in the next patch, we don't want an
O_DIRECT write to imply a queue unplug.

Signed-off-by: default avatarJeff Moyer <jmoyer@redhat.com>
Signed-off-by: default avatarJens Axboe <jens.axboe@oracle.com>
parent 1a1238a7

fs/direct-io.c

+1 −1
Original line number Diff line number Diff line
@@ -1124,7 +1124,7 @@ __blockdev_direct_IO(int rw, struct kiocb *iocb, struct inode *inode, 
	int acquire_i_mutex = 0;



	if (rw & WRITE)

		rw = WRITE_ODIRECT;

		rw = WRITE_SYNC_PLUG;



	if (bdev)

		bdev_blkbits = blksize_bits(bdev_logical_block_size(bdev));

include/linux/fs.h

+0 −2
Original line number Diff line number Diff line
@@ -129,7 +129,6 @@ struct inodes_stat_t { 
 * WRITE_SYNC		Like WRITE_SYNC_PLUG, but also unplugs the device

 *			immediately after submission. The write equivalent

 *			of READ_SYNC.

 * WRITE_ODIRECT	Special case write for O_DIRECT only.

 * SWRITE_SYNC

 * SWRITE_SYNC_PLUG	Like WRITE_SYNC/WRITE_SYNC_PLUG, but locks the buffer.

 *			See SWRITE.
@@ -151,7 +150,6 @@ struct inodes_stat_t { 
#define READ_META	(READ | (1 << BIO_RW_META))

#define WRITE_SYNC_PLUG	(WRITE | (1 << BIO_RW_SYNCIO) | (1 << BIO_RW_NOIDLE))

#define WRITE_SYNC	(WRITE_SYNC_PLUG | (1 << BIO_RW_UNPLUG))

#define WRITE_ODIRECT	(WRITE | (1 << BIO_RW_SYNCIO) | (1 << BIO_RW_UNPLUG))

#define SWRITE_SYNC_PLUG	\

			(SWRITE | (1 << BIO_RW_SYNCIO) | (1 << BIO_RW_NOIDLE))

#define SWRITE_SYNC	(SWRITE_SYNC_PLUG | (1 << BIO_RW_UNPLUG))

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