From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:51973) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZOM9m-0001tE-6L for qemu-devel@nongnu.org; Sun, 09 Aug 2015 04:40:39 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ZOM9j-00047v-01 for qemu-devel@nongnu.org; Sun, 09 Aug 2015 04:40:38 -0400 Received: from hall.aurel32.net ([2001:bc8:30d7:100::1]:43227) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZOM9i-00047o-Lj for qemu-devel@nongnu.org; Sun, 09 Aug 2015 04:40:34 -0400 Date: Sun, 9 Aug 2015 10:40:20 +0200 From: Aurelien Jarno Message-ID: <20150809084020.GA5883@aurel32.net> References: <1438966995-5913-1-git-send-email-a.rigo@virtualopensystems.com> <1438966995-5913-6-git-send-email-a.rigo@virtualopensystems.com> <20150808124401.GA18166@aurel32.net> <871tfcnann.fsf@linaro.org> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-15 Content-Disposition: inline Content-Transfer-Encoding: quoted-printable In-Reply-To: <871tfcnann.fsf@linaro.org> Subject: Re: [Qemu-devel] [RFC v4 5/9] configure: Enable/disable new qemu_{ld, st} excl insns List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Alex =?iso-8859-15?Q?Benn=E9e?= Cc: mttcg@listserver.greensocs.com, claudio.fontana@huawei.com, Alvise Rigo , qemu-devel@nongnu.org, pbonzini@redhat.com, jani.kokkonen@huawei.com, tech@virtualopensystems.com On 2015-08-09 09:11, Alex Benn=E9e wrote: >=20 > Aurelien Jarno writes: >=20 > > On 2015-08-07 19:03, Alvise Rigo wrote: > >> Introduce the new --enable-tcg-ldst-excl configure option to enable the > >> LL/SC operations only for those backends that support them. > >>=20 > >> Suggested-by: Jani Kokkonen > >> Suggested-by: Claudio Fontana > >> Signed-off-by: Alvise Rigo > >> --- > >> configure | 21 +++++++++++++++++++++ > >> 1 file changed, 21 insertions(+) > > > > We have seen that for this kind of patch, it's better to add support in > > all backends, otherwise it takes ages to get all the backends converted. > > I think you should involve the backend maintainers. I can try to provide > > the corresponding patches for mips and ia64. >=20 > We discussed this on the last MTTCG call and agree. However we will need > help from the other TCG maintainers for the backends. The changes should > be fairly mechanical though. >=20 > However in the spirit of keeping trees building in the meantime should > we change this from a configure option to just a static option for each > given backend as it is converted? I am not even sure we need a static option. I guess providing we are doing that early enough in the 2.5 cycle, we can just add the new ops and start using them. Of course we should put the backends maintainers in the loop so they can fix that quickly and don't get a surprise weeks afters. That said, please see my other email, I am not sure we actually need to modify backends, I think we can implement these new "ops" through tcg-runtime. Aurelien --=20 Aurelien Jarno GPG: 4096R/1DDD8C9B aurelien@aurel32.net http://www.aurel32.net