From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andre Przywara Subject: Re: [PATCH] RFC: Linux: disable APERF/MPERF feature in PV kernels Date: Wed, 23 May 2012 11:52:57 +0200 Message-ID: <4FBCB379.90908@amd.com> References: <4FBBB9AF.6020704@amd.com> <4FBCAF1902000078000855C5@nat28.tlf.novell.com> <4FBCAA6F.2060708@amd.com> <4FBCCD76020000780008569E@nat28.tlf.novell.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii"; Format="flowed" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <4FBCCD76020000780008569E@nat28.tlf.novell.com> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: Jan Beulich Cc: Jeremy Fitzhardinge , xen-devel , Konrad Rzeszutek Wilk List-Id: xen-devel@lists.xenproject.org On 05/23/2012 11:43 AM, Jan Beulich wrote: >>>> On 23.05.12 at 11:14, Andre Przywara wrote: >> On 05/23/2012 09:34 AM, Jan Beulich wrote: >>> Next I'd like to note that in our kernels we simply don't build >>> arch/x86/kernel/cpu/sched.o. Together with CPU_FREQ being >>> suppressed, there's no consumer of the feature flag in our >>> kernels. >> >> With "our kernels" you mean OpenSuSE/SLES kernels? I quickly checked >> upstream as well as the repos on kernel.opensuse.org. In all of them >> sched.o is unconditionally included in the Makefile. >> So is there a build patch to exclude this file for builds of distro Xen >> kernels? > > Did you perhaps overlook > > disabled-obj-$(CONFIG_XEN) := hypervisor.o mshyperv.o perfctr-watchdog.o \ > perf_event.o sched.o vmware.o > > in that very Makefile? No, I just utterly ignored it ;-) Thanks for the hint. But this works only for SuSE since you build different kernels for Xen and without Xen, right? Starting with 3.x I now have only a single kernel image which I use for both native and as Dom0. So the patch to disable APERFMPERF is still useful, at least for upstream, right? Regards, Andre. -- Andre Przywara AMD-Operating System Research Center (OSRC), Dresden, Germany