From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:41992) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Z5qlf-0004mY-QC for qemu-devel@nongnu.org; Fri, 19 Jun 2015 03:31:16 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Z5qla-0002LB-V5 for qemu-devel@nongnu.org; Fri, 19 Jun 2015 03:31:15 -0400 Received: from mx1.redhat.com ([209.132.183.28]:58071) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Z5qla-0002L5-P6 for qemu-devel@nongnu.org; Fri, 19 Jun 2015 03:31:10 -0400 Message-ID: <5583C538.6010707@redhat.com> Date: Fri, 19 Jun 2015 09:31:04 +0200 From: Paolo Bonzini MIME-Version: 1.0 References: <1434642290-17610-1-git-send-email-fred.konrad@greensocs.com> <5BED6CA1-C0F5-4F08-A508-0DED044B5AEF@greensocs.com> In-Reply-To: <5BED6CA1-C0F5-4F08-A508-0DED044B5AEF@greensocs.com> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Subject: Re: [Qemu-devel] [RFC PATCH V3] Use atomic cmpxchg to atomically check the exclusive value in a STREX List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Mark Burton , Peter Maydell Cc: mttcg@greensocs.com, Alexander Graf , QEMU Developers , Guillaume Delbergue , =?UTF-8?B?QWxleCBCZQ==?= =?UTF-8?B?bm7DqWU=?= , =?UTF-8?B?S09OUkFEIEZyw6lkw6lyaWM=?= On 19/06/2015 09:29, Mark Burton wrote: > Does anybody know if the current atomic_cmpxchg will support 64 bit > on a (normal) 32 bit x86, or do we need to special case that with > cmpxchg8b ? (I get the impression that it will automatically use > cmpxchg8b, but not cmpxchg16b - but I=E2=80=99m by no means sure). Both cmpxchg8b and cmpxchg16b are used, respectively on 32-bit and 64-bit x86. Paolo