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Date: Sat, 13 Feb 2010 00:16:58 -0800
From: "H. Peter Anvin" <hpa@zytor.com>
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To: Avi Kivity <avi@redhat.com>
CC: linux-kernel@vger.kernel.org
Subject: Re: [PATCH] x86-64, rwsem: Avoid store forwarding hazzard in __downgrade_write
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On 02/12/2010 11:13 PM, Avi Kivity wrote:
> +#ifndef CONFIG_X86_64
> +		       "i" (-RWSEM_WAITING_BIAS)
> +#else
> +		       "r" (-RWSEM_WAITING_BIAS)
>  #endif
> +		     : "memory", "cc");

Using an "er" constraint here should work on both architectures.

	-hpa

-- 
H. Peter Anvin, Intel Open Source Technology Center
I work for Intel.  I don't speak on their behalf.