From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933652Ab2AKRYj (ORCPT ); Wed, 11 Jan 2012 12:24:39 -0500 Received: from mga01.intel.com ([192.55.52.88]:28779 "EHLO mga01.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755320Ab2AKRYe (ORCPT ); Wed, 11 Jan 2012 12:24:34 -0500 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.71,315,1320652800"; d="scan'208";a="106055438" From: "Fenghua Yu" To: "Ingo Molnar" , "Thomas Gleixner" , "H Peter Anvin" , "Linus Torvalds" , "Andrew Morton" , "Asit K Mallick" , "Tony Luck" , "Arjan van de Ven" , "Suresh B Siddha" , "Len Brown" , "Randy Dunlap" , "Srivatsa S. Bhat" , Konrad Rzeszutek Wilk , Peter Zijlstra , "Chen Gong" , "linux-kernel" , "linux-pm" , "x86" Cc: Fenghua Yu Subject: [PATCH v5 0/12] x86: Arbitrary CPU hot(un)plug support Date: Wed, 11 Jan 2012 09:04:41 -0800 Message-Id: <1326301493-28760-1-git-send-email-fenghua.yu@intel.com> X-Mailer: git-send-email 1.7.2 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Fenghua Yu CPU0 or BSP (Bootstrap Processor) has been the last processor that can not be hot removed on x86. This patch set implements CPU0 or BSP online and offline and removes this obstacle to CPU hotplug. RAS needs the feature. If socket0 needs to be hotplugged for any reason (any thread on socket0 is bad, shared cache issue, uncore issue, etc), CPU0 is required to be offline or hot replaced to keep the system run. For example, starting with Core Duo, if you have a system that is reporting cache problems via the "yellow" status in the MCi_STATUS msr, then there is benefit in simply soft off-lining the cores that share that cache - assuming that leaves you at least one online core. A single socket system with L3 cache troubles is not helped - but problems in L1/L2 cache, or on multi-socket systems can be avoided. They are already being avoided for the cases where CPU0 is not involved. This patchset can help L1/L2 cache problem in CPU0 or L3 cache problem on the socket with CPU0 in a multi-socket system. v5: Add CONFIG_BOOTPARAM_HOTPLUG_CPU0 and CONFIG_DEBUG_HOTPLUG_CPU0. Simplify duplicate xstate_size init check. Wakeup CPU0 via nmi instead INITs. Add mcheck_cpu_init when CPU0 online. Change variable bsp_hotpluggable to cpu0_hotpluggable with __initdata qualifier. v4: Add __read_mostly for internal bsp_hotpluggable variable. Add my email address in cpu-hotplug.txt document. A wording change in comment. v3: Register a pm notifier to check if CPU0 is online before hibernate/suspend. Small wording changes in document and print info. v2: Add locking changes between cpu hotplug and hibernate/suspend. Change PIC irq bound to CPU0 detection. Fenghua Yu (12): Documentations/cpu-hotplug.tx, kernel-parameters.txt: Add x86 CPU0 online/offline feature x86/Kconfig: Add config switch for CPU0 hotplug x86/topology.c: Support functions for CPU0 online/offline x86/smpboot.c: Don't offline CPU0 if any irq can not be migrated out of it and remove CPU0 check in smp_callin() x86/power/cpu.c: Don't hibernate/suspend if CPU0 is offline x86/head_64.S: Define start_cpu0 x86/head_32.S: Define start_cpu0 x86/smpboot.c: Wake up CPU0 via NMI instead of INITs x86/common.c: Init CPU0 data during CPU0 online x86/mtrr/main.c: Ask the first online CPU to save mtrr x86/i387.c: Thread xstate is initialized only on CPU0 once x86/topology.c: debug CPU0 hotplug Documentation/cpu-hotplug.txt | 24 +++++++ Documentation/kernel-parameters.txt | 14 ++++ arch/x86/Kconfig | 44 ++++++++++++ arch/x86/include/asm/cpu.h | 1 + arch/x86/include/asm/processor.h | 1 + arch/x86/kernel/cpu/common.c | 17 ++++- arch/x86/kernel/cpu/mtrr/main.c | 9 ++- arch/x86/kernel/head_32.S | 17 ++++- arch/x86/kernel/head_64.S | 15 ++++ arch/x86/kernel/i387.c | 6 ++- arch/x86/kernel/smpboot.c | 124 +++++++++++++++++++++++++++++++---- arch/x86/kernel/topology.c | 66 +++++++++++++++++-- arch/x86/power/cpu.c | 44 ++++++++++++ 13 files changed, 352 insertions(+), 30 deletions(-)