[PATCH] f2fs: remove redundant block plug

From: Chao Yu
Date: Sat Apr 07 2018 - 23:38:07 EST


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@xxxxxxxxxx>
Signed-off-by: Chao Yu <yuchao0@xxxxxxxxxx>
---
fs/f2fs/file.c | 3 ---
1 file changed, 3 deletions(-)

diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c
index 7b8fb31086c3..cb315d23c56f 100644
--- a/fs/f2fs/file.c
+++ b/fs/f2fs/file.c
@@ -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. */
--
2.15.0.55.gc2ece9dc4de6