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Date: Mon, 3 Mar 2025 18:37:01 -0800
From: Andrew Morton <akpm@linux-foundation.org>
To: Dave Hansen <dave.hansen@linux.intel.com>
Cc: linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org,
 tytso@mit.edu, willy@infradead.org, mjguzik@gmail.com, david@fromorbit.com
Subject: Re: [PATCH] [v2] filemap: Move prefaulting out of hot write path
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In-Reply-To: <20250228203722.CAEB63AC@davehans-spike.ostc.intel.com>
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On Fri, 28 Feb 2025 12:37:22 -0800 Dave Hansen <dave.hansen@linux.intel.com> wrote:

> There is a generic anti-pattern that shows up in the VFS and several
> filesystems where the hot write paths touch userspace twice when they
> could get away with doing it once.
> 
> Dave Chinner suggested that they should all be fixed up[1]. I agree[2].
> But, the series to do that fixup spans a bunch of filesystems and a lot
> of people. This patch fixes common code that absolutely everyone uses.
> It has measurable performance benefits[3].
> 
> I think this patch can go in and not be held up by the others.

I'll queue this in mm-hotfixes with a view to sneaking it into 6.14-rcX
as a basis for others to work against.