From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751832AbbFXVQN (ORCPT ); Wed, 24 Jun 2015 17:16:13 -0400 Received: from mga14.intel.com ([192.55.52.115]:21580 "EHLO mga14.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750966AbbFXVQD (ORCPT ); Wed, 24 Jun 2015 17:16:03 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.13,673,1427785200"; d="scan'208";a="734022290" Date: Wed, 24 Jun 2015 14:13:21 -0700 (PDT) From: Vikas Shivappa X-X-Sender: vikas@vshiva-Udesk To: Thomas Gleixner cc: Vikas Shivappa , linux-kernel@vger.kernel.org, x86@kernel.org, hpa@zytor.com, mingo@kernel.org, tj@kernel.org, peterz@infradead.org, matt.fleming@intel.com, will.auld@intel.com, glenn.p.williamson@intel.com, kanaka.d.juvva@intel.com, priya.v.autee@intel.com Subject: Re: [PATCH 02/10] x86/intel_cqm: Modify hot cpu notification handling In-Reply-To: Message-ID: References: <1435100183-21720-1-git-send-email-vikas.shivappa@linux.intel.com> <1435100183-21720-3-git-send-email-vikas.shivappa@linux.intel.com> User-Agent: Alpine 2.10 (DEB 1266 2009-07-14) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII; format=flowed Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 24 Jun 2015, Thomas Gleixner wrote: > On Tue, 23 Jun 2015, Vikas Shivappa wrote: > >> This patch modifies hot cpu notification handling in Intel cache >> monitoring: >> >> - to add a new cpu to the cqm_cpumask(which has one cpu per package) >> during cpu start, it uses the existing package<->core map instead of >> looping through all cpus in cqm_cpumask. >> - to search for the next online sibling during cpu exit, it uses the >> cpumask_any_online_but instead of looping through all online cpus. In >> large systems with large number of cpus the time taken to loop may be >> expensive and also the time increase linearly. > > Of course, you forgot to mention that you added the mutex around it > and changed the hotplug logic by moving the calls to different hotplug > events. That part wants to be a seperate patch anyway. Will do. will send them as seperate patches. Thanks, Vikas