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	Wed, 10 May 2006 11:47:28 -0400
Date: Wed, 10 May 2006 08:47:02 -0700
From: Richard Henderson <rth@twiddle.net>
Subject: Re: [RFC/PATCH] Make powerpc64 use __thread for per-cpu variables
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To: Paul Mackerras <paulus@samba.org>, t@twiddle.net
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On Wed, May 10, 2006 at 02:03:59PM +1000, Paul Mackerras wrote:
> With this patch, 64-bit powerpc uses __thread for per-cpu variables.

How do you plan to address the compiler optimizing

	__thread int foo;
	{
	  use(foo);
	  schedule();
	  use(foo);
	}

into

	{
	  int *tmp = &foo;	// tls arithmetic here
	  use(*tmp);
	  schedule();
	  use(*tmp);
	}

Across the schedule, we may have changed cpus, making the cached
address invalid.


r~