From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-4.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 60AC6C0650E for ; Wed, 3 Jul 2019 11:04:39 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3FE38218A3 for ; Wed, 3 Jul 2019 11:04:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727205AbfGCLES (ORCPT ); Wed, 3 Jul 2019 07:04:18 -0400 Received: from Galois.linutronix.de ([193.142.43.55]:51630 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727079AbfGCLEL (ORCPT ); Wed, 3 Jul 2019 07:04:11 -0400 Received: from localhost ([127.0.0.1] helo=nanos.tec.linutronix.de) by Galois.linutronix.de with esmtp (Exim 4.80) (envelope-from ) id 1hid3a-0002c6-0k; Wed, 03 Jul 2019 13:04:10 +0200 Message-Id: <20190703105916.377516522@linutronix.de> User-Agent: quilt/0.65 Date: Wed, 03 Jul 2019 12:54:40 +0200 From: Thomas Gleixner To: LKML Cc: x86@kernel.org, Nadav Amit , Ricardo Neri , Stephane Eranian , Feng Tang Subject: [patch 09/18] smp/hotplug: Track booted once CPUs in a cpumask References: <20190703105431.096822793@linutronix.de> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The booted once information which is required to deal with the MCE broadcast issue on X86 correctly is stored in the per cpu hotplug state, which is perfectly fine for the intended purpose. X86 needs that information for supporting NMI broadcasting via shortcuts, but retrieving it from per cpu data is cumbersome. Move it to a cpumask so the information can be checked against the cpu_present_mask quickly. No functional change intended. Signed-off-by: Thomas Gleixner --- include/linux/cpumask.h | 2 ++ kernel/cpu.c | 11 +++++++---- 2 files changed, 9 insertions(+), 4 deletions(-) --- a/include/linux/cpumask.h +++ b/include/linux/cpumask.h @@ -115,6 +115,8 @@ extern struct cpumask __cpu_active_mask; #define cpu_active(cpu) ((cpu) == 0) #endif +extern cpumask_t cpus_booted_once_mask; + static inline void cpu_max_bits_warn(unsigned int cpu, unsigned int bits) { #ifdef CONFIG_DEBUG_PER_CPU_MAPS --- a/kernel/cpu.c +++ b/kernel/cpu.c @@ -62,7 +62,6 @@ struct cpuhp_cpu_state { bool rollback; bool single; bool bringup; - bool booted_once; struct hlist_node *node; struct hlist_node *last; enum cpuhp_state cb_state; @@ -76,6 +75,10 @@ static DEFINE_PER_CPU(struct cpuhp_cpu_s .fail = CPUHP_INVALID, }; +#ifdef CONFIG_SMP +cpumask_t cpus_booted_once_mask; +#endif + #if defined(CONFIG_LOCKDEP) && defined(CONFIG_SMP) static struct lockdep_map cpuhp_state_up_map = STATIC_LOCKDEP_MAP_INIT("cpuhp_state-up", &cpuhp_state_up_map); @@ -433,7 +436,7 @@ static inline bool cpu_smt_allowed(unsig * CPU. Otherwise, a broadacasted MCE observing CR4.MCE=0b on any * core will shutdown the machine. */ - return !per_cpu(cpuhp_state, cpu).booted_once; + return !cpumask_test_cpu(cpu, &cpus_booted_once_mask); } #else static inline bool cpu_smt_allowed(unsigned int cpu) { return true; } @@ -1066,7 +1069,7 @@ void notify_cpu_starting(unsigned int cp int ret; rcu_cpu_starting(cpu); /* Enables RCU usage on this CPU. */ - st->booted_once = true; + cpumask_set_cpu(cpu, &cpus_booted_once_mask); while (st->state < target) { st->state++; ret = cpuhp_invoke_callback(cpu, st->state, true, NULL, NULL); @@ -2324,7 +2327,7 @@ void __init boot_cpu_init(void) void __init boot_cpu_hotplug_init(void) { #ifdef CONFIG_SMP - this_cpu_write(cpuhp_state.booted_once, true); + cpumask_set_cpu(smp_processor_id(), &cpus_booted_once_mask); #endif this_cpu_write(cpuhp_state.state, CPUHP_ONLINE); }