From mboxrd@z Thu Jan  1 00:00:00 1970
From: Chris Down <chris-6Bi1550iOqEnzZ6mRAm98g@public.gmane.org>
Subject: Re: [PATCH] mm: Make mem_cgroup_id_get_many dependent on MMU and
 MEMCG_SWAP
Date: Thu, 5 Mar 2020 18:34:26 +0000
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To: Johannes Weiner <hannes-druUgvl0LCNAfugRpC6u6w@public.gmane.org>
Cc: Vincenzo Frascino <vincenzo.frascino-5wv7dgnIgG8@public.gmane.org>, Michal Hocko <mhocko-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>, cgroups-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-mm-Bw31MaZKKs3YtjvyW6yDsg@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Vladimir Davydov <vdavydov.dev-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>, Andrew Morton <akpm-de/tnXTf+JLsfHDXvbKv3WD2FQJk+8+b@public.gmane.org>

Johannes Weiner writes:
>I would ack a patch that adds __maybe_unused.
>
>This is a tiny function. If we keep it around a few releases after
>removing the last user, it costs us absolutely nothing. Eventually
>somebody will notice and send a patch to remove it. No big deal.
>
>There is, however, real cost in keeping bogus warnings around and
>telling people to ignore them. It's actively lowering the
>signal-to-noise ratio and normalizing warnings to developers. That's
>the kind of thing that will actually hide problems in the kernel.
>
>We know that the function can be unused in certain scenarios. It's
>silly to let the compiler continue to warn about it. That's exactly
>what __maybe_unused is for, so let's use it here.

Yeah, this is exactly what I was trying to express in the first one[0]. The 
fact that this patch came around a second time, as expected, just solidifies my 
concern around the waste to human time.

I would also ack a patch that adds __maybe_unused.

0: https://lore.kernel.org/linux-mm/20191217143720.GB131030-6Bi1550iOqEnzZ6mRAm98g@public.gmane.org/