From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1947245AbcHRM7C (ORCPT ); Thu, 18 Aug 2016 08:59:02 -0400 Received: from Galois.linutronix.de ([146.0.238.70]:44073 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1947167AbcHRM6T (ORCPT ); Thu, 18 Aug 2016 08:58:19 -0400 From: Sebastian Andrzej Siewior To: linux-kernel@vger.kernel.org Cc: Peter Zijlstra , Ingo Molnar , rt@linutronix.de, Sebastian Andrzej Siewior , Gleb Natapov , Paolo Bonzini , kvm@vger.kernel.org Subject: [PATCH 14/16] x86: kvm: Convert to hotplug state machine Date: Thu, 18 Aug 2016 14:57:29 +0200 Message-Id: <20160818125731.27256-15-bigeasy@linutronix.de> X-Mailer: git-send-email 2.9.3 In-Reply-To: <20160818125731.27256-1-bigeasy@linutronix.de> References: <20160818125731.27256-1-bigeasy@linutronix.de> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Install the callbacks via the state machine. The online & down callbacks are invoke on the target CPU so we can avoid using smp_call_function_single(). local_irq_disable() is used because smp_call_function_single() used to invoke the function with interrupts disabled. Cc: Gleb Natapov Cc: Paolo Bonzini Cc: kvm@vger.kernel.org Signed-off-by: Sebastian Andrzej Siewior --- arch/x86/kernel/kvm.c | 42 +++++++++++++++--------------------------- 1 file changed, 15 insertions(+), 27 deletions(-) diff --git a/arch/x86/kernel/kvm.c b/arch/x86/kernel/kvm.c index 1726c4c12336..d1fcb2d3c976 100644 --- a/arch/x86/kernel/kvm.c +++ b/arch/x86/kernel/kvm.c @@ -423,12 +423,7 @@ static void __init kvm_smp_prepare_boot_cpu(void) kvm_spinlock_init(); } -static void kvm_guest_cpu_online(void *dummy) -{ - kvm_guest_cpu_init(); -} - -static void kvm_guest_cpu_offline(void *dummy) +static void kvm_guest_cpu_offline(void) { kvm_disable_steal_time(); if (kvm_para_has_feature(KVM_FEATURE_PV_EOI)) @@ -437,29 +432,21 @@ static void kvm_guest_cpu_offline(void *dummy) apf_task_wake_all(); } -static int kvm_cpu_notify(struct notifier_block *self, unsigned long action, - void *hcpu) +static int kvm_cpu_online(unsigned int cpu) { - int cpu = (unsigned long)hcpu; - switch (action) { - case CPU_ONLINE: - case CPU_DOWN_FAILED: - case CPU_ONLINE_FROZEN: - smp_call_function_single(cpu, kvm_guest_cpu_online, NULL, 0); - break; - case CPU_DOWN_PREPARE: - case CPU_DOWN_PREPARE_FROZEN: - smp_call_function_single(cpu, kvm_guest_cpu_offline, NULL, 1); - break; - default: - break; - } - return NOTIFY_OK; + local_irq_disable(); + kvm_guest_cpu_init(); + local_irq_enable(); + return 0; } -static struct notifier_block kvm_cpu_notifier = { - .notifier_call = kvm_cpu_notify, -}; +static int kvm_cpu_down_prepare(unsigned int cpu) +{ + local_irq_disable(); + kvm_guest_cpu_offline(); + local_irq_enable(); + return 0; +} #endif static void __init kvm_apf_trap_init(void) @@ -494,7 +481,8 @@ void __init kvm_guest_init(void) #ifdef CONFIG_SMP smp_ops.smp_prepare_boot_cpu = kvm_smp_prepare_boot_cpu; - register_cpu_notifier(&kvm_cpu_notifier); + cpuhp_setup_state_nocalls(CPUHP_AP_ONLINE_DYN, "X86_KVM_ONLINE", + kvm_cpu_online, kvm_cpu_down_prepare); #else kvm_guest_cpu_init(); #endif -- 2.9.3