From mboxrd@z Thu Jan  1 00:00:00 1970
Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43)
	id 1NjaD0-0006dE-Hd
	for qemu-devel@nongnu.org; Mon, 22 Feb 2010 10:28:30 -0500
Received: from [199.232.76.173] (port=43835 helo=monty-python.gnu.org)
	by lists.gnu.org with esmtp (Exim 4.43) id 1NjaD0-0006cl-0e
	for qemu-devel@nongnu.org; Mon, 22 Feb 2010 10:28:30 -0500
Received: from Debian-exim by monty-python.gnu.org with spam-scanned (Exim
	4.60) (envelope-from <avi@redhat.com>) id 1NjaCy-0004QU-RU
	for qemu-devel@nongnu.org; Mon, 22 Feb 2010 10:28:29 -0500
Received: from mx1.redhat.com ([209.132.183.28]:63499)
	by monty-python.gnu.org with esmtp (Exim 4.60)
	(envelope-from <avi@redhat.com>) id 1NjaCy-0004Q8-BL
	for qemu-devel@nongnu.org; Mon, 22 Feb 2010 10:28:28 -0500
Message-ID: <4B82A299.4090608@redhat.com>
Date: Mon, 22 Feb 2010 17:28:25 +0200
From: Avi Kivity <avi@redhat.com>
MIME-Version: 1.0
References: <20100222135906.347393434@amt.cnet>
	<20100222140210.130087300@amt.cnet>
	<4B829364.7020300@redhat.com> <20100222144541.GC18992@amt.cnet>
	<4B829B59.3020803@redhat.com> <20100222145739.GC20580@redhat.com>
	<4B829DD0.4010009@redhat.com> <20100222150848.GD20580@redhat.com>
In-Reply-To: <20100222150848.GD20580@redhat.com>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
Content-Transfer-Encoding: 7bit
Subject: [Qemu-devel] Re: [patch uq/master 2/2] kvm-all.c: define smp_wmb
 and use it for coalesced mmio
List-Id: qemu-devel.nongnu.org
List-Unsubscribe: <http://lists.nongnu.org/mailman/listinfo/qemu-devel>,
	<mailto:qemu-devel-request@nongnu.org?subject=unsubscribe>
List-Archive: <http://lists.gnu.org/pipermail/qemu-devel>
List-Post: <mailto:qemu-devel@nongnu.org>
List-Help: <mailto:qemu-devel-request@nongnu.org?subject=help>
List-Subscribe: <http://lists.nongnu.org/mailman/listinfo/qemu-devel>,
	<mailto:qemu-devel-request@nongnu.org?subject=subscribe>
To: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>, qemu-devel@nongnu.org, kvm@vger.kernel.org

On 02/22/2010 05:08 PM, Michael S. Tsirkin wrote:
>
>>
>>>> I imagine all arches need an instruction.  For reads as well.
>>>>
>>>> Note, gcc has a __sync_synchronize() builtin that compiles to mfence on
>>>> x86.  We might use that as a baseline for both rmb and wmb, and let each
>>>> arch override it incrementally.
>>>>
>>>>          
>>> This it what my patch did. Note it only works well for recent gcc.
>>>
>>>        
>> Do you know how recent?
>>      
> IIRC 4.3 has broken implementation.
> 4.4 seems OK as far as I can tell.
>    

Well, so that idea's down.

-- 
error compiling committee.c: too many arguments to function