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Date: Thu, 25 Jun 2026 15:03:36 +0200
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
Message-ID: <20260625130336.GD22620@lst.de>
References: <20260625024723.1611000-1-joannelkoong@gmail.com>
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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.