From mboxrd@z Thu Jan  1 00:00:00 1970
Received: from eggs.gnu.org ([2001:4830:134:3::10]:36720)
	by lists.gnu.org with esmtp (Exim 4.71)
	(envelope-from <peter.maydell@linaro.org>) id 1dagRQ-0004cC-1I
	for qemu-devel@nongnu.org; Thu, 27 Jul 2017 06:54:52 -0400
Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71)
	(envelope-from <peter.maydell@linaro.org>) id 1dagRP-0004Tw-BF
	for qemu-devel@nongnu.org; Thu, 27 Jul 2017 06:54:52 -0400
Received: from mail-wm0-x22a.google.com ([2a00:1450:400c:c09::22a]:34964)
	by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_128_CBC_SHA1:16)
	(Exim 4.71) (envelope-from <peter.maydell@linaro.org>)
	id 1dagRP-0004Sv-1q
	for qemu-devel@nongnu.org; Thu, 27 Jul 2017 06:54:51 -0400
Received: by mail-wm0-x22a.google.com with SMTP id c184so101629791wmd.0
	for <qemu-devel@nongnu.org>; Thu, 27 Jul 2017 03:54:50 -0700 (PDT)
MIME-Version: 1.0
In-Reply-To: <20170727104302.GI2555@redhat.com>
References: <150091574424.30739.4131793221953168474.stgit@frigg.lan>
	<20170725131931.GC23343@stefanha-x1.localdomain>
	<CAFEAcA_pmFYZ_y9E5D0c70G2oA62vb+KBXnxbp_Sg39kuNeREA@mail.gmail.com>
	<20170726112633.GE18489@stefanha-x1.localdomain>
	<CAFEAcA_pXX6ZCsBwAQnzQbTSbxzAh=nFpPeEzZoRBhBDt2r+vA@mail.gmail.com>
	<20170727104302.GI2555@redhat.com>
From: Peter Maydell <peter.maydell@linaro.org>
Date: Thu, 27 Jul 2017 11:54:29 +0100
Message-ID: <CAFEAcA8oyHi+7NVCE8YWHY+v0UXLbt2tWHGE4AP_V8TtDBc89g@mail.gmail.com>
Content-Type: text/plain; charset="UTF-8"
Subject: Re: [Qemu-devel] [PATCH 00/13] instrument: Add basic event
 instrumentation
List-Id: <qemu-devel.nongnu.org>
List-Unsubscribe: <https://lists.nongnu.org/mailman/options/qemu-devel>,
	<mailto:qemu-devel-request@nongnu.org?subject=unsubscribe>
List-Archive: <http://lists.nongnu.org/archive/html/qemu-devel/>
List-Post: <mailto:qemu-devel@nongnu.org>
List-Help: <mailto:qemu-devel-request@nongnu.org?subject=help>
List-Subscribe: <https://lists.nongnu.org/mailman/listinfo/qemu-devel>,
	<mailto:qemu-devel-request@nongnu.org?subject=subscribe>
To: "Daniel P. Berrange" <berrange@redhat.com>
Cc: Stefan Hajnoczi <stefanha@redhat.com>, Stefan Hajnoczi <stefanha@gmail.com>, "Emilio G. Cota" <cota@braap.org>, =?UTF-8?Q?Llu=C3=ADs_Vilanova?= <vilanova@ac.upc.edu>, QEMU Developers <qemu-devel@nongnu.org>

On 27 July 2017 at 11:43, Daniel P. Berrange <berrange@redhat.com> wrote:
> Maybe I'm missing something, but aren't all these things
> already possible via either the statically defined tracepoints
> QEMU exposes, or by placing dynamic tracepoints on arbitrary
> code locations using dtrace/systemtap/lttng-ust.

Last time I looked we didn't have tracepoints on most of
the events you'd be interested in.

That said, yes, I was going to ask if we could do this via
leveraging the tracepoint infrastructure and whatever scripting
facilities it provides. Are there any good worked examples of
this sort of thing? Can you do it as an ordinary non-root user?

thanks
-- PMM