Re: [PATCH v3] checkpatch: ignore warning designated initializers using NR_CPUS

From: Joe Perches
Date: Wed Dec 30 2020 - 07:40:07 EST


On Wed, 2020-12-30 at 20:29 +0800, Peng Wang wrote:
> Some max_length wants to hold as large room as possible to
> ensure enough size to tackle with the biggest NR_CPUS.
> An example below:
>
> kernel/cgroup/cpuset.c:
> static struct cftype legacy_files[] = {
>         {
>                 .name = "cpus",
>                 .seq_show = cpuset_common_seq_show,
>                 .write = cpuset_write_resmask,
>                 .max_write_len = (100U + 6 * NR_CPUS),
>                 .private = FILE_CPULIST,
>         },
> ...
> }
>
> Signed-off-by: Peng Wang <rocking@xxxxxxxxxxxxxxxxx>
> ---
[]
> diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
[]
> @@ -7028,12 +7028,14 @@ sub process {
>  
>  # use of NR_CPUS is usually wrong
>  # ignore definitions of NR_CPUS and usage to define arrays as likely right
> +# ignore designated initializers using NR_CPUS
>   if ($line =~ /\bNR_CPUS\b/ &&
>   $line !~ /^.\s*\s*#\s*if\b.*\bNR_CPUS\b/ &&
>   $line !~ /^.\s*\s*#\s*define\b.*\bNR_CPUS\b/ &&
>   $line !~ /^.\s*$Declare\s.*\[[^\]]*NR_CPUS[^\]]*\]/ &&
>   $line !~ /\[[^\]]*\.\.\.[^\]]*NR_CPUS[^\]]*\]/ &&
> - $line !~ /\[[^\]]*NR_CPUS[^\]]*\.\.\.[^\]]*\]/)
> + $line !~ /\[[^\]]*NR_CPUS[^\]]*\.\.\.[^\]]*\]/ &&
> + $line !~ /^.\s*\.\w+\s*=\s*.*\bNR_CPUS\b/)
>   {
>   WARN("NR_CPUS",
>   "usage of NR_CPUS is often wrong - consider using cpu_possible(), num_possible_cpus(), for_each_possible_cpu(), etc\n" . $herecurr);

Thanks.

Acked-by: Joe Perches <joe@xxxxxxxxxxx>