Re: [PATCH v3 02/11] MIPS: Remove unused variable 'lastpfn'

[Ralf Baechle <ralf@linux-mips.org>]

On Mon, Nov 13, 2017 at 10:30:18PM -0600, Steven J. Hill wrote:
> Date:   Mon, 13 Nov 2017 22:30:18 -0600
> From: "Steven J. Hill" <steven.hill@cavium.com>
> To: linux-mips@linux-mips.org
> Cc: "Steven J. Hill" <Steven.Hill@cavium.com>, ralf@linux-mips.org
> Subject: [PATCH v3 02/11] MIPS: Remove unused variable 'lastpfn'
> Content-Type: text/plain
> 
> From: "Steven J. Hill" <Steven.Hill@cavium.com>
> 
> 'lastpfn' is never used for anything. Remove it.
> 
> Signed-off-by: Steven J. Hill <steven.hill@cavium.com>
> Acked-by: David Daney <david.daney@cavium.com
> ---
>  arch/mips/mm/init.c | 4 ----
>  1 file changed, 4 deletions(-)
> 
> diff --git a/arch/mips/mm/init.c b/arch/mips/mm/init.c
> index 5f6ea7d..84b7b59 100644
> --- a/arch/mips/mm/init.c
> +++ b/arch/mips/mm/init.c
> @@ -402,7 +402,6 @@ int page_is_ram(unsigned long pagenr)
>  void __init paging_init(void)
>  {
>  	unsigned long max_zone_pfns[MAX_NR_ZONES];
> -	unsigned long lastpfn __maybe_unused;
>  
>  	pagetable_init();
>  
> @@ -416,17 +415,14 @@ void __init paging_init(void)
>  	max_zone_pfns[ZONE_DMA32] = MAX_DMA32_PFN;
>  #endif
>  	max_zone_pfns[ZONE_NORMAL] = max_low_pfn;
> -	lastpfn = max_low_pfn;
>  #ifdef CONFIG_HIGHMEM
>  	max_zone_pfns[ZONE_HIGHMEM] = highend_pfn;
> -	lastpfn = highend_pfn;
>  
>  	if (cpu_has_dc_aliases && max_low_pfn != highend_pfn) {
>  		printk(KERN_WARNING "This processor doesn't support highmem."
>  		       " %ldk highmem ignored\n",
>  		       (highend_pfn - max_low_pfn) << (PAGE_SHIFT - 10));
>  		max_zone_pfns[ZONE_HIGHMEM] = max_low_pfn;
> -		lastpfn = max_low_pfn;
>  	}
>  #endif

This cleanup is an excellent demonstration for why __maybe_unused is a
less than great idea.

  Ralf