Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751719AbaJOOyD (ORCPT ); Wed, 15 Oct 2014 10:54:03 -0400 Received: from aserp1040.oracle.com ([141.146.126.69]:30689 "EHLO aserp1040.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751378AbaJOOyB (ORCPT ); Wed, 15 Oct 2014 10:54:01 -0400 From: Boris Ostrovsky To: tglx@linutronix.de, mingo@redhat.com, hpa@zytor.com, konrad.wilk@oracle.com, david.vrabel@citrix.com Cc: tianyu.lan@intel.com, linux-kernel@vger.kernel.org, xen-devel@lists.xenproject.org, boris.ostrovsky@oracle.com Subject: [PATCH] xen/smp: Use die_complete completion when taking CPU down Date: Wed, 15 Oct 2014 10:55:10 -0400 Message-Id: <1413384910-1231-1-git-send-email-boris.ostrovsky@oracle.com> X-Mailer: git-send-email 1.8.1.4 X-Source-IP: acsinet22.oracle.com [141.146.126.238] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Commit 2ed53c0d6cc9 ("x86/smpboot: Speed up suspend/resume by avoiding 100ms sleep for CPU offline during S3") introduced completions to CPU offlining process. These completions are not initialized on Xen kernels causing a panic in play_dead_common(). Add handling of die_complete on Xen (this requires moving die_complete to global scope. While at it, move die_complete definition in arch/x86/kernel/smpboot.c under ifdef CONFIG_HOTPLUG_CPU) Signed-off-by: Boris Ostrovsky --- arch/x86/include/asm/cpu.h | 3 +++ arch/x86/kernel/smpboot.c | 4 +++- arch/x86/xen/smp.c | 4 ++++ 3 files changed, 10 insertions(+), 1 deletion(-) diff --git a/arch/x86/include/asm/cpu.h b/arch/x86/include/asm/cpu.h index d2b1298..b65d5c9 100644 --- a/arch/x86/include/asm/cpu.h +++ b/arch/x86/include/asm/cpu.h @@ -6,6 +6,7 @@ #include #include #include +#include #ifdef CONFIG_SMP @@ -26,6 +27,8 @@ struct x86_cpu { }; #ifdef CONFIG_HOTPLUG_CPU +DECLARE_PER_CPU(struct completion, die_complete); + extern int arch_register_cpu(int num); extern void arch_unregister_cpu(int); extern void start_cpu0(void); diff --git a/arch/x86/kernel/smpboot.c b/arch/x86/kernel/smpboot.c index 2d5200e..abe9005 100644 --- a/arch/x86/kernel/smpboot.c +++ b/arch/x86/kernel/smpboot.c @@ -102,7 +102,9 @@ DEFINE_PER_CPU_READ_MOSTLY(cpumask_var_t, cpu_llc_shared_map); DEFINE_PER_CPU_SHARED_ALIGNED(struct cpuinfo_x86, cpu_info); EXPORT_PER_CPU_SYMBOL(cpu_info); -static DEFINE_PER_CPU(struct completion, die_complete); +#ifdef CONFIG_HOTPLUG_CPU +DEFINE_PER_CPU(struct completion, die_complete); +#endif atomic_t init_deasserted; diff --git a/arch/x86/xen/smp.c b/arch/x86/xen/smp.c index 8650cdb..4da0008 100644 --- a/arch/x86/xen/smp.c +++ b/arch/x86/xen/smp.c @@ -498,6 +498,7 @@ static int xen_cpu_disable(void) if (cpu == 0) return -EBUSY; + init_completion(&per_cpu(die_complete, smp_processor_id())); cpu_disable_common(); load_cr3(swapper_pg_dir); @@ -510,6 +511,9 @@ static void xen_cpu_die(unsigned int cpu) current->state = TASK_UNINTERRUPTIBLE; schedule_timeout(HZ/10); } + + wait_for_completion_timeout(&per_cpu(die_complete, cpu), HZ); + xen_smp_intr_free(cpu); xen_uninit_lock_cpu(cpu); xen_teardown_timer(cpu); -- 1.8.1.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/