From mboxrd@z Thu Jan 1 00:00:00 1970 From: =?UTF-8?Q?Roger_Pau_Monn=c3=a9?= Subject: Re: [PATCH v6 18/29] xen/x86: allow disabling the emulated pmu Date: Fri, 25 Sep 2015 17:07:40 +0200 Message-ID: <5605633C.8000708@citrix.com> References: <1441368548-43465-1-git-send-email-roger.pau@citrix.com> <1441368548-43465-19-git-send-email-roger.pau@citrix.com> <560031F602000078000A4186@prv-mh.provo.novell.com> <560018C7.9040004@oracle.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Received: from mail6.bemta3.messagelabs.com ([195.245.230.39]) by lists.xen.org with esmtp (Exim 4.72) (envelope-from ) id 1ZfUbB-0001vc-OQ for xen-devel@lists.xenproject.org; Fri, 25 Sep 2015 15:07:45 +0000 In-Reply-To: <560018C7.9040004@oracle.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: Boris Ostrovsky , Jan Beulich Cc: Andrew Cooper , xen-devel@lists.xenproject.org List-Id: xen-devel@lists.xenproject.org El 21/09/15 a les 16.48, Boris Ostrovsky ha escrit: > On 09/21/2015 10:36 AM, Jan Beulich wrote: >>>>> On 04.09.15 at 14:08, wrote: >> Hmm - this seems questionable to me: Isn't the vPMU an optional >> feature anyway? I.e. doesn't need separate handling here? Boris? > > It is optional system-wise, not per-guest, which is what I think Roger > is trying to do. I in fact wanted to add ability to disable VPMU per > guest myself. > > However, VPMU has nothing to do with device model so I don't think it > should be part of this series from that perspective. vpmu is enabled globally on the xen command line, there's no way to disable it on a per-guest basis, so AFAICS it will be enabled for HMVlite guests which is wrong because we don't have a vlapic. IMHO, there's no need to add a flag to specifically disable the vpmu, we can just decide whether to enable it based on vlapic presence and the global vpmu flag. Roger.