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Date:   Fri, 26 Aug 2022 14:29:14 +0100
From:   Aaron Tomlin <atomlin@redhat.com>
To:     Andrew Morton <akpm@linux-foundation.org>
Cc:     Marcelo Tosatti <mtosatti@redhat.com>, frederic@kernel.org,
        cl@linux.com, tglx@linutronix.de, mingo@kernel.org,
        peterz@infradead.org, pauld@redhat.com, neelx@redhat.com,
        oleksandr@natalenko.name, linux-kernel@vger.kernel.org,
        linux-mm@kvack.org
Subject: Re: [PATCH v7 1/3] mm/vmstat: Use per cpu variable to track a vmstat
 discrepancy
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 <20220817191524.140710201@redhat.com>
 <20220824132054.54ec0472496db153223282c4@linux-foundation.org>
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On Wed 2022-08-24 13:20 -0700, Andrew Morton wrote:
> > --- linux-2.6.orig/mm/vmstat.c
> > +++ linux-2.6/mm/vmstat.c
> > @@ -195,6 +195,12 @@ void fold_vm_numa_events(void)
> >  #endif
> >  
> >  #ifdef CONFIG_SMP
> > +static DEFINE_PER_CPU_ALIGNED(bool, vmstat_dirty);
> > +
> > +static inline void mark_vmstat_dirty(void)
> > +{
> > +	this_cpu_write(vmstat_dirty, true);
> > +}
> 
> If we're to have a helper for this then how about helpers for clearing
> it and reading it?
> 
> Also, vmstat_mark_dirty(), vmstat_clear_dirty() and vmstat_dirty()
> would be better identifiers.
> 
> Then those helper functions become good sites for comments explaining
> what's going on.
> 

Hi Andrew,

Fair enough. I'll work on that.


Kind regards,

-- 
Aaron Tomlin