From: Christoph Hellwig <hch@infradead.org>
To: Pavel Begunkov <asml.silence@gmail.com>
Cc: Christoph Hellwig <hch@infradead.org>,
Jens Axboe <axboe@kernel.dk>,
linux-block@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH v2 2/3] block: don't hide inode from block_device users
Date: Thu, 14 Oct 2021 05:51:13 +0100 [thread overview]
Message-ID: <YWe3QZD+g8MSoCtT@infradead.org> (raw)
In-Reply-To: <194577df-0402-6e3c-3534-af289b5494e0@gmail.com>
On Wed, Oct 13, 2021 at 07:44:20PM +0100, Pavel Begunkov wrote:
> Mildly hot in io_uring w/o fixed files, but that's not peak perf,
> but would also be great to get rid of bdev->bd_inode dereference,
> e.g. lots of in fops.c.
>
> Are you going to just hid the dereference in helpers or kill it
> with some offseting magic?
The only real hot path uses I found is the size (which you and Jens
already seem to have moved to use something out of the inode for the
fast path), and maybe the blkbits for which we could do the same.
So basically the idea is to not touch the inode in the hot path,
and use accessors helpers in bdev.c that could do the offsetof trick.
next prev parent reply other threads:[~2021-10-14 4:54 UTC|newest]
Thread overview: 16+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-10-13 8:57 [PATCH v2 0/3] on top of for-5.16/block Pavel Begunkov
2021-10-13 8:57 ` [PATCH v2 1/3] block: cache bdev in struct file for raw bdev IO Pavel Begunkov
2021-10-13 15:19 ` Christoph Hellwig
2021-10-13 8:57 ` [PATCH v2 2/3] block: don't hide inode from block_device users Pavel Begunkov
2021-10-13 14:03 ` kernel test robot
2021-10-13 15:03 ` kernel test robot
2021-10-13 15:12 ` Pavel Begunkov
2021-10-15 0:40 ` [kbuild-all] " Chen, Rong A
2021-10-13 15:25 ` Christoph Hellwig
2021-10-13 18:44 ` Pavel Begunkov
2021-10-14 4:51 ` Christoph Hellwig [this message]
2021-10-14 9:35 ` Pavel Begunkov
2021-10-13 8:57 ` [PATCH v2 3/3] blk-mq: optimise *end_request non-stat path Pavel Begunkov
2021-10-13 15:30 ` Christoph Hellwig
2021-10-13 9:15 ` [PATCH v2 0/3] on top of for-5.16/block Pavel Begunkov
2021-10-13 15:53 ` (subset) " 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=YWe3QZD+g8MSoCtT@infradead.org \
--to=hch@infradead.org \
--cc=asml.silence@gmail.com \
--cc=axboe@kernel.dk \
--cc=linux-block@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
/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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).