RE: [PATCH 7/7] ext4: add support for write stream IDs

Ming Lin-SSI
2015-03-26T20:36:06Z

> -----Original Message-----
> From: Jens Axboe [mailto:axboe@fb.com]
> Sent: Wednesday, March 25, 2015 8:08 AM
> To: linux-kernel@vger.kernel.org; linux-fsdevel@vger.kernel.org
> Cc: Ming Lin-SSI; david@fromorbit.com; Jens Axboe
> Subject: [PATCH 7/7] ext4: add support for write stream IDs
>
> Signed-off-by: Jens Axboe <axboe@fb.com>
> ---
> fs/ext4/page-io.c | 1 +
> 1 file changed, 1 insertion(+)
>
> diff --git a/fs/ext4/page-io.c b/fs/ext4/page-io.c index
> b24a2541a9ba..f642d0b87a32 100644
> --- a/fs/ext4/page-io.c
> +++ b/fs/ext4/page-io.c
> @@ -390,6 +390,7 @@ submit_and_retry:
> ret = io_submit_init_bio(io, bh);
> if (ret)
> return ret;
> + bio_set_streamid(io->io_bio, inode_streamid(inode));

For "writeback" and "ordered" journal mode, it should be OK.

But for "journal" journal mode,
Step1: data written to journal
Step2: data written from journal to fs

Do we need other code to carry stream_id in step2?

Thanks,
Ming

> }
> ret = bio_add_page(io->io_bio, bh->b_page, bh->b_size,
> bh_offset(bh));
> if (ret != bh->b_size)
> --
> 1.9.1