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Date:   Fri, 10 Jul 2020 16:57:19 +0100
From:   Matthew Wilcox <willy@infradead.org>
To:     Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc:     Cyrill Gorcunov <gorcunov@gmail.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] kcmp: add separate Kconfig symbol for kcmp syscall
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On Fri, Jul 10, 2020 at 09:56:31AM +0200, Rasmus Villemoes wrote:
> The ability to check open file descriptions for equality (without
> resorting to unreliable fstat() and fcntl(F_GETFL) comparisons) can be
> useful outside of the checkpoint/restore use case - for example,
> systemd uses kcmp() to deduplicate the per-service file descriptor
> store.
> 
> Make it possible to have the kcmp() syscall without the full
> CONFIG_CHECKPOINT_RESTORE.

If systemd is using it, is it even worth making it conditional any more?
Maybe for CONFIG_EXPERT builds, it could be de-selectable.