From mboxrd@z Thu Jan 1 00:00:00 1970 From: Chao Peng Subject: Re: [PATCH v10 02/13] x86: detect and initialize Intel CAT feature Date: Wed, 8 Jul 2015 10:24:16 +0800 Message-ID: <20150708022416.GA3333@pengc-linux.bj.intel.com> References: <1435308227-30586-1-git-send-email-chao.p.peng@linux.intel.com> <1435308227-30586-3-git-send-email-chao.p.peng@linux.intel.com> <559BC54A020000780008D46E@mail.emea.novell.com> Reply-To: Chao Peng Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: Content-Disposition: inline In-Reply-To: <559BC54A020000780008D46E@mail.emea.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: wei.liu2@citrix.com, Ian.Campbell@citrix.com, stefano.stabellini@eu.citrix.com, andrew.cooper3@citrix.com, dario.faggioli@citrix.com, Ian.Jackson@eu.citrix.com, xen-devel@lists.xen.org, will.auld@intel.com, keir@xen.org, dgdegra@tycho.nsa.gov List-Id: xen-devel@lists.xenproject.org On Tue, Jul 07, 2015 at 11:25:46AM +0100, Jan Beulich wrote: > >>> On 26.06.15 at 10:43, wrote: > > Detect Intel Cache Allocation Technology(CAT) feature and store the > > cpuid information for later use. Currently only L3 cache allocation is > > supported. The L3 CAT features may vary among sockets so per-socket > > feature information is stored. The initialization can happen either at > > boot time or when CPU(s) is hot plugged after booting. > > > > Signed-off-by: Chao Peng > > Reviewed-by: Andrew Cooper > > --- > > Changes in v0: > > * Add comment for cpu notification priority. > > I'm afraid you did this just mechanically, while I implied you to also > verify that what you chose is correct: > > > static struct notifier_block cpu_nfb = { > > - .notifier_call = cpu_callback > > + .notifier_call = cpu_callback, > > + /* > > + * Ensure socket_cpumask is still valid in CPU_DEAD notification > > + * (E.g. the CPU_DEAD notification should be called ahead of > > + * cpu_smpboot_free). > > + */ > > + .priority = 1 > > CPU_DEAD is a NOTIFY_REVERSE notification, i.e. lowest priority > first. I.e. your comment now contradicts the code afaict. Unless > I'm mistaken with that, I assume you didn't really test this code > path? Since everything else is fine with this patch, I'd be fine > with doing the adjustment while committing, but I need your > confirmation which variant actually works. > Sorry for this. But It's really your change is correct. Also see your typo fix, looks much better and thanks. Chao