linux-mm.kvack.org archive mirror
 help / color / mirror / Atom feed
From: Christoph Hellwig <hch@infradead.org>
To: Jens Axboe <axboe@kernel.dk>
Cc: Andrew Morton <akpm@linux-foundation.org>,
	Dave Chinner <david@fromorbit.com>,
	"linux-fsdevel@vger.kernel.org" <linux-fsdevel@vger.kernel.org>,
	Linux Memory Management List <linux-mm@kvack.org>,
	Chris Mason <clm@fb.com>, Pavel Begunkov <asml.silence@gmail.com>
Subject: Re: mm: don't read i_size of inode unless we need it
Date: Thu, 28 Oct 2021 07:19:09 -0700	[thread overview]
Message-ID: <YXqxXXDYtKetgZY0@infradead.org> (raw)
In-Reply-To: <6b67981f-57d4-c80e-bc07-6020aa601381@kernel.dk>

Btw, given that you're micro-optimizing in this area:

block devices still use ->direct_IO in the I/O path.  It might make
sense to switch to the model of the file systems that use iomap where
we avoid that indirect call and can optimize the code for the direct
I/O fast path.  With that you woudn't even end up using this i_size_read
at all


  parent reply	other threads:[~2021-10-28 14:19 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-10-26 18:15 Jens Axboe
2021-10-26 19:11 ` Chris Mason
2021-10-27 15:50   ` Jens Axboe
2021-10-28 14:19 ` Christoph Hellwig [this message]
2021-10-28 15:00   ` 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=YXqxXXDYtKetgZY0@infradead.org \
    --to=hch@infradead.org \
    --cc=akpm@linux-foundation.org \
    --cc=asml.silence@gmail.com \
    --cc=axboe@kernel.dk \
    --cc=clm@fb.com \
    --cc=david@fromorbit.com \
    --cc=linux-fsdevel@vger.kernel.org \
    --cc=linux-mm@kvack.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