From: "Theodore Y. Ts'o" <tytso@mit.edu>
To: Jens Axboe <axboe@kernel.dk>
Cc: linux-fsdevel@vger.kernel.org, viro@zeniv.linux.org.uk,
akpm@linux-foundation.org
Subject: Re: [PATCH 3/3] ext4: readpages() should submit IO as read-ahead
Date: Thu, 24 May 2018 16:47:30 -0400 [thread overview]
Message-ID: <20180524204730.GC7712@thunk.org> (raw)
In-Reply-To: <1527177774-21414-4-git-send-email-axboe@kernel.dk>
On Thu, May 24, 2018 at 10:02:54AM -0600, Jens Axboe wrote:
> a_ops->readpages() is only ever used for read-ahead. Ensure that we
> pass this information down to the block layer.
>
> Signed-off-by: Jens Axboe <axboe@kernel.dk>
> ---
> fs/ext4/readpage.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/fs/ext4/readpage.c b/fs/ext4/readpage.c
> index 9ffa6fad18db..92b28273b223 100644
> --- a/fs/ext4/readpage.c
> +++ b/fs/ext4/readpage.c
> @@ -259,7 +259,7 @@ int ext4_mpage_readpages(struct address_space *mapping,
> bio->bi_iter.bi_sector = blocks[0] << (blkbits - 9);
> bio->bi_end_io = mpage_end_io;
> bio->bi_private = ctx;
> - bio_set_op_attrs(bio, REQ_OP_READ, 0);
> + bio_set_op_attrs(bio, REQ_OP_READ, REQ_RAHEAD);
> }
The problem is that ext4_readpage() also calls ext4_mpage_readpages().
So you can't set REQ_RAHEAD unconditionally here.
- Ted
next prev parent reply other threads:[~2018-05-24 20:47 UTC|newest]
Thread overview: 16+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-05-24 16:02 [PATCHSET 0/3] Submit ->readpages() IO as read-ahead Jens Axboe
2018-05-24 16:02 ` [PATCH 1/3] mpage: mpage_readpages() should submit " Jens Axboe
2018-05-24 19:43 ` Andrew Morton
2018-05-24 19:57 ` Matthew Wilcox
2018-05-24 20:24 ` Jens Axboe
2018-05-29 14:36 ` Jens Axboe
2018-05-29 21:59 ` Andrew Morton
2018-05-29 22:18 ` Jens Axboe
2018-05-29 22:37 ` Jens Axboe
2018-05-24 16:02 ` [PATCH 2/3] btrfs: readpages() " Jens Axboe
2018-05-24 16:02 ` [PATCH 3/3] ext4: " Jens Axboe
2018-05-24 20:47 ` Theodore Y. Ts'o [this message]
2018-05-24 20:53 ` Jens Axboe
2018-05-24 21:05 ` Jens Axboe
2018-05-25 8:32 ` [PATCHSET 0/3] Submit ->readpages() " Christoph Hellwig
2018-05-25 14:21 ` Jens Axboe
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20180524204730.GC7712@thunk.org \
--to=tytso@mit.edu \
--cc=akpm@linux-foundation.org \
--cc=axboe@kernel.dk \
--cc=linux-fsdevel@vger.kernel.org \
--cc=viro@zeniv.linux.org.uk \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.