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	Mon, 26 May 2025 00:25:20 +0000
Date: Mon, 26 May 2025 01:25:19 +0100
From: Al Viro <viro@zeniv.linux.org.uk>
To: Collin Funk <collin.funk1@gmail.com>
Cc: linux-kernel@vger.kernel.org
Subject: Re: [PATCH] groups: Use bsearch instead of hand rolled implementation
Message-ID: <20250526002519.GX2023217@ZenIV>
References: <ab5708c1e35e1b2a54a1d83fafda1b3f8fa01103.1748218528.git.collin.funk1@gmail.com>
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Sender: Al Viro <viro@ftp.linux.org.uk>

On Sun, May 25, 2025 at 05:17:46PM -0700, Collin Funk wrote:
> This code predates <linux/bsearch.h>. Now that the bsearch function
> exists there we can use it to reduce code duplication.

Careful - that really needs profiling with setups where processes have
a bunch of supplementary groups.

It *is* on hot paths, and while the current version will be inlined,
yours will do a bunch of indirect calls.  These days that can be
costly.

Reducing code duplication is a good thing, but not when it creates
measurable regressions...