From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:52992) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1X794s-0003Vt-4Q for qemu-devel@nongnu.org; Tue, 15 Jul 2014 16:12:00 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1X794h-00049L-W1 for qemu-devel@nongnu.org; Tue, 15 Jul 2014 16:11:54 -0400 Received: from mx1.redhat.com ([209.132.183.28]:50536) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1X794h-00049G-Nk for qemu-devel@nongnu.org; Tue, 15 Jul 2014 16:11:43 -0400 Message-ID: <53C58AF6.40206@redhat.com> Date: Tue, 15 Jul 2014 22:11:34 +0200 From: Paolo Bonzini MIME-Version: 1.0 References: <1405424541-21803-1-git-send-email-alex.bennee@linaro.org> <1405424541-21803-4-git-send-email-alex.bennee@linaro.org> <53C52A66.5000906@redhat.com> <871ttmyabr.fsf@linaro.org> In-Reply-To: <871ttmyabr.fsf@linaro.org> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: quoted-printable Subject: Re: [Qemu-devel] [PATCH v2 3/3] trace: instrument and trace tcg tb flush activity List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: =?UTF-8?B?QWxleCBCZW5uw6ll?= Cc: mohamad.gebai@gmail.com, qemu-devel@nongnu.org, stefanha@redhat.com, =?UTF-8?B?QW5kcmVhcyBGw6Ry?= =?UTF-8?B?YmVy?= Il 15/07/2014 16:16, Alex Benn=C3=A9e ha scritto: >> > I think this is premature optimization... > How do you mean? It's not really an optimization as much as an > instrumentation. It should compile away to nothing if you don't have > tracing enabled in your build. I think it's not a big deal if you always enable the counting, and=20 perhaps show them in "info jit". Paolo > OTOH the numbers I'm seeing are very interesting in so far as the fast > path could be a potential waste of code in a lot of cases.