Commit 47cca3d6 authored Apr 04, 2018 by Chao Yu Committed by Jaegeuk Kim May 31, 2018

f2fs: remove redundant block plug



For buffered IO, we don't need to use block plug to cache bio,
for direct IO, generic f2fs_direct_IO has already added block
plug, so let's remove redundant one in .write_iter.

As Yunlei described in his patch:

-f2fs_file_write_iter
  -blk_start_plug
    -__generic_file_write_iter
	...
	  -do_blockdev_direct_IO
	    -blk_start_plug
		...
	    -blk_finish_plug
	...
  -blk_finish_plug

which may conduct performance decrease in our platform

Signed-off-by: Yunlei He <heyunlei@huawei.com>
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>

parent 80452498

fs/f2fs/file.c

+0 −3

Original line number	Diff line number	Diff line
		@@ -2886,7 +2886,6 @@ static ssize_t f2fs_file_write_iter(struct kiocb iocb, struct iov_iter from)
		{
		struct file *file = iocb->ki_filp;
		struct inode *inode = file_inode(file);
		struct blk_plug plug;
		ssize_t ret;

		if (unlikely(f2fs_cp_error(F2FS_I_SB(inode))))
		@@ -2931,9 +2930,7 @@ static ssize_t f2fs_file_write_iter(struct kiocb iocb, struct iov_iter from)
		return err;
		}
		}
		blk_start_plug(&plug);
		ret = __generic_file_write_iter(iocb, from);
		blk_finish_plug(&plug);
		clear_inode_flag(inode, FI_NO_PREALLOC);

		/* if we couldn't write data, we should deallocate blocks. */

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