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Date: Sat, 23 Feb 2002 14:10:25 -0800
From: Andrew Morton <akpm@zip.com.au>
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To: Roman Zippel <zippel@linux-m68k.org>
CC: yodaiken@fsmlabs.com, Robert Love <rml@tech9.net>,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH] only irq-safe atomic ops
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Roman Zippel wrote:
> 
> Hi,
> 
> yodaiken@fsmlabs.com wrote:
> 
> > Right. Without preemption it is safe to do
> >         c = smp_get_cpuid();
> >        ...
> >         x = ++local_cache[c]
> >        ..
> >
> >        y = ++different_local_cache[c];
> >       ..
> 
> Just add:
>         smp_put_cpuid();
> 
> Is that so much worse?
> 

ooh.  me likee.

#define smp_get_cpuid() ({ preempt_disable(); smp_processor_id(); })
#define smp_put_cpuid() preempt_enable()

Does rml likee?

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