From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([140.186.70.92]:60280) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1QzHnD-0001DU-No for qemu-devel@nongnu.org; Thu, 01 Sep 2011 20:39:37 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1QzHn9-0000m5-Kn for qemu-devel@nongnu.org; Thu, 01 Sep 2011 20:39:35 -0400 Received: from e23smtp07.au.ibm.com ([202.81.31.140]:33498) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1QzHn8-0000lR-Pt for qemu-devel@nongnu.org; Thu, 01 Sep 2011 20:39:31 -0400 Received: from d23relay05.au.ibm.com (d23relay05.au.ibm.com [202.81.31.247]) by e23smtp07.au.ibm.com (8.14.4/8.13.1) with ESMTP id p820dGb1028071 for ; Fri, 2 Sep 2011 10:39:16 +1000 Received: from d23av01.au.ibm.com (d23av01.au.ibm.com [9.190.234.96]) by d23relay05.au.ibm.com (8.13.8/8.13.8/NCO v10.0) with ESMTP id p820bhXg1470576 for ; Fri, 2 Sep 2011 10:37:46 +1000 Received: from d23av01.au.ibm.com (loopback [127.0.0.1]) by d23av01.au.ibm.com (8.14.4/8.13.1/NCO v10.0 AVout) with ESMTP id p820dDT5013620 for ; Fri, 2 Sep 2011 10:39:13 +1000 Date: Fri, 2 Sep 2011 10:08:50 +1000 From: David Gibson Message-ID: <20110902000850.GL11906@yookeroo.fritz.box> References: <1314857389-13363-1-git-send-email-david@gibson.dropbear.id.au> <4E5F2A95.6000403@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4E5F2A95.6000403@redhat.com> Subject: Re: [Qemu-devel] [PATCH] virtio: Make memory barriers be memory barriers List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Paolo Bonzini Cc: aik@ozlabs.ru, aliguori@us.ibm.com, rusty@rustcorp.com.au, qemu-devel@nongnu.org, agraf@suse.de On Thu, Sep 01, 2011 at 08:47:49AM +0200, Paolo Bonzini wrote: > On 09/01/2011 08:09 AM, David Gibson wrote: > >The patch defines wmb() as __sync_synchronize(), a cross platform memory > >barrier primitive available in sufficiently recent gcc versions (gcc 4.2 > >and after?). If we care about older gccs then this patch will need to > >be updated with some sort of fallback. > > Yes, though RHEL5's 4.1 has it backported. > > >Signed-off-by: Alexey Kardashevskiy > >Signed-off-by: David Gibson > > It will most definitely break OpenBSD, but anyway: Uh, why? -- David Gibson | I'll have my music baroque, and my code david AT gibson.dropbear.id.au | minimalist, thank you. NOT _the_ _other_ | _way_ _around_! http://www.ozlabs.org/~dgibson