Re: [mmotm:master 130/230] mm/swap.c:719:2: error: implicit declaration of function 'TestSetPageMlocked'

[Johannes Weiner <hannes@cmpxchg.org>]

On Fri, Jun 20, 2014 at 02:14:16PM -0700, Andrew Morton wrote:
> On Fri, 20 Jun 2014 10:09:27 +0800 kbuild test robot <fengguang.wu@intel.com> wrote:
> 
> > tree:   git://git.cmpxchg.org/linux-mmotm.git master
> > head:   df25ba7db0775d87018e2cd92f26b9b087093840
> > commit: 8d72d7b20fab14a779df2f7ea7632d4ee223dfcc [130/230] mm: memcontrol: rewrite charge API
> > config: make ARCH=m32r m32104ut_defconfig
> > 
> > All error/warnings:
> > 
> >    mm/swap.c: In function 'lru_cache_add_active_or_unevictable':
> > >> mm/swap.c:719:2: error: implicit declaration of function 'TestSetPageMlocked' [-Werror=implicit-function-declaration]
> >    cc1: some warnings being treated as errors
> > 
> > vim +/TestSetPageMlocked +719 mm/swap.c
> > 
> >    713		if (likely((vma->vm_flags & (VM_LOCKED | VM_SPECIAL)) != VM_LOCKED)) {
> >    714			SetPageActive(page);
> >    715			lru_cache_add(page);
> >    716			return;
> >    717		}
> >    718	
> >  > 719		if (!TestSetPageMlocked(page)) {
> >    720			/*
> >    721			 * We use the irq-unsafe __mod_zone_page_stat because this
> >    722			 * counter is not modified from interrupt context, and the pte
> > 
> 
> hm, I can't think of anything very smart here.
> 
> --- a/mm/swap.c~mm-memcontrol-rewrite-charge-api-fix-2
> +++ a/mm/swap.c
> @@ -716,6 +716,7 @@ void lru_cache_add_active_or_unevictable
>  		return;
>  	}
>  
> +#ifdef CONFIG_MMU
>  	if (!TestSetPageMlocked(page)) {
>  		/*
>  		 * We use the irq-unsafe __mod_zone_page_stat because this
> @@ -726,6 +727,7 @@ void lru_cache_add_active_or_unevictable
>  				    hpage_nr_pages(page));
>  		count_vm_event(UNEVICTABLE_PGMLOCKED);
>  	}
> +#else
>  	add_page_to_unevictable_list(page);
>  }

We can define TestSetPageMlocked() for !MMU configurations.  I don't
have a suitable toolchain available right now, so this is untested.

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