From mboxrd@z Thu Jan 1 00:00:00 1970 From: Stephane Eranian Date: Wed, 08 Mar 2006 21:22:21 +0000 Subject: Re: 2.6.16-rc5 perfmon2 new code base + libpfm with Montecito support Message-Id: <20060308212221.GB14435@frankl.hpl.hp.com> List-Id: References: <20060308155311.GD13168@frankl.hpl.hp.com> <440F4130.5040703@redhat.com> In-Reply-To: <440F4130.5040703@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: William Cohen Cc: linux-kernel@vger.kernel.org, perfmon@napali.hpl.hp.com, perfctr-devel@lists.sourceforge.net, linux-ia64@vger.kernel.org Will, On Wed, Mar 08, 2006 at 03:40:16PM -0500, William Cohen wrote: > > > >I have released another version of the perfmon new base package. > >This release is relative to 2.6.16-rc5 > > Hello Stephane, > > Is there any thoughts on how perfmon2 is going to work with xen enabled > kernels or processors that support virtualization? > AFAIK, there is currently no Xen support for PMU on any platforms. By "support" I mean suport for guests using the PMU. As such, I do not think this works. I am planning on looking at this next because this is becoming a pressing matter and not just on IA-64. My first goal is to ensure that a guest using perfmon2 works once it is virtualized. That implies that the Xen VMM does save/restore PMU state on guest switch. That's a bare minimum. As for HW virutlization support, I think it helps a little bit but there still needs to be some additional code in the VMM to make this work correctly. This is also something I want to look at. -- -Stephane