From mboxrd@z Thu Jan 1 00:00:00 1970 From: "Jan Beulich" Subject: Re: [PATCH v5 2/6] x86: allow reading MSR_IA32_TSC with XENPF_resource_op Date: Thu, 22 Jan 2015 13:36:53 +0000 Message-ID: <54C10B05020000780005824E@mail.emea.novell.com> References: <1421839164-26037-1-git-send-email-chao.p.peng@linux.intel.com> <1421839164-26037-3-git-send-email-chao.p.peng@linux.intel.com> <54C0EAFF0200007800058100@mail.emea.novell.com> <20150122125314.GD28428@pengc-linux.bj.intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20150122125314.GD28428@pengc-linux.bj.intel.com> Content-Disposition: inline List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: Chao Peng Cc: wei.liu2@citrix.com, Ian.Campbell@citrix.com, stefano.stabellini@eu.citrix.com, Ian.Jackson@eu.citrix.com, xen-devel@lists.xen.org, will.auld@intel.com, keir@xen.org List-Id: xen-devel@lists.xenproject.org >>> On 22.01.15 at 13:53, wrote: > On Thu, Jan 22, 2015 at 11:20:15AM +0000, Jan Beulich wrote: >> >>> On 21.01.15 at 12:19, wrote: >> > --- a/xen/arch/x86/platform_hypercall.c >> > +++ b/xen/arch/x86/platform_hypercall.c >> > @@ -61,7 +61,7 @@ long cpu_down_helper(void *data); >> > long core_parking_helper(void *data); >> > uint32_t get_cur_idle_nums(void); >> > >> > -#define RESOURCE_ACCESS_MAX_ENTRIES 2 >> > +#define RESOURCE_ACCESS_MAX_ENTRIES 3 >> >> See my comment on an earlier version. > The new added MSR_IA32_TSC and existed MSR_IA32_CMT_CTR should be > read in an atomic unit. How to achieve this if not increase > MAX_ENTRIES? These are just two entries nevertheless. Jan