Linux XFS filesystem development
 help / color / mirror / Atom feed
From: Christoph Hellwig <hch@lst.de>
To: Joanne Koong <joannelkoong@gmail.com>
Cc: hch@lst.de, willy@infradead.org, djwong@kernel.org,
	linux-fsdevel@vger.kernel.org, linux-xfs@vger.kernel.org
Subject: Re: [RFC PATCH v1 0/3] iomap: convert to in-iter ->iomap_next() model
Date: Thu, 25 Jun 2026 15:03:36 +0200	[thread overview]
Message-ID: <20260625130336.GD22620@lst.de> (raw)
In-Reply-To: <20260625024723.1611000-1-joannelkoong@gmail.com>

On Wed, Jun 24, 2026 at 07:47:20PM -0700, Joanne Koong wrote:
> A few questions:
> * is this roughly the in-iter direction you had in mind?

I like it.

> * is removing the indirect call still worth it? My understanding is that
>   indirect calls are cheap on modern eIBRS hardware and the conversion adds
>   some per-filesystem boilerplate, so I'm unsure if it carries its weight. If
>   not, do you think the in-iter model is still worth having on its own?

Indirect calls have always been relatively slow, even without spectre.
So if we can easily avoid them that's always a win.  That doesn't mean we
should do stupid things just to avoid them, but I think we have a win/win
here.


      parent reply	other threads:[~2026-06-25 13:03 UTC|newest]

Thread overview: 15+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2026-06-25  2:47 [RFC PATCH v1 0/3] iomap: convert to in-iter ->iomap_next() model Joanne Koong
2026-06-25  2:47 ` [RFC PATCH v1 1/3] iomap: add ->iomap_next() and iomap_process() helper Joanne Koong
2026-06-25 12:56   ` Christoph Hellwig
2026-06-25 21:03     ` Joanne Koong
2026-06-25  2:47 ` [RFC PATCH v1 2/3] xfs: convert read and buffered write iomap ops to ->iomap_next() Joanne Koong
2026-06-25  2:47 ` [RFC PATCH v1 3/3] xfs: example of devirtualizing buffered write iomap callbacks Joanne Koong
2026-06-25 13:00   ` Christoph Hellwig
2026-06-25 20:46     ` Joanne Koong
2026-06-25  3:25 ` [RFC PATCH v1 0/3] iomap: convert to in-iter ->iomap_next() model Gao Xiang
2026-06-25  3:37   ` Gao Xiang
2026-06-25 13:02   ` Christoph Hellwig
2026-06-25 13:21     ` Gao Xiang
2026-06-25 21:33       ` Joanne Koong
2026-06-26  2:22         ` Gao Xiang
2026-06-25 13:03 ` Christoph Hellwig [this message]

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=20260625130336.GD22620@lst.de \
    --to=hch@lst.de \
    --cc=djwong@kernel.org \
    --cc=joannelkoong@gmail.com \
    --cc=linux-fsdevel@vger.kernel.org \
    --cc=linux-xfs@vger.kernel.org \
    --cc=willy@infradead.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