Subject: Re: [PATCH] mm/percpu: mark pcpu_chunk_type() as __maybe_unused

From: Stephen Rothwell <[email-masked]>
Date: Tue, 14 Jul 2020 22:53:11 +1000

Hi Bixuan,

On Tue, 14 Jul 2020 13:41:01 +0000 Bixuan Cui <[email-masked]> wrote:
>
> Gcc report the following warning without CONFIG_MEMCG_KMEM:
> 
> mm/percpu-internal.h:145:29: warning: ‘pcpu_chunk_type’ defined
> but not used [-Wunused-function]
>  static enum pcpu_chunk_type pcpu_chunk_type(struct pcpu_chunk *chunk)
>                              ^~~~~~~~~~~~~~~
> 
> Mark pcpu_chunk_type() as __maybe_unused to make it clear.

Given that it is in a header file, it should probably just be "static
inline" (which will also suppress the warning).  As should
pcpu_is_memcg_chunk() and pcpu_chunk_list().  Also, without them being
inline, there will be a new copy for each file that
mm/percpu-internal.h is included in.

And that should be considered a fix for "mm: memcg/percpu: account
percpu memory to memory cgroups".

-- 
Cheers,
Stephen Rothwell