From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1030630AbcGKMjd (ORCPT ); Mon, 11 Jul 2016 08:39:33 -0400 Received: from www.linutronix.de ([62.245.132.108]:57288 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758699AbcGKMbB (ORCPT ); Mon, 11 Jul 2016 08:31:01 -0400 Message-Id: <20160711122533.574124290@linutronix.de> User-Agent: quilt/0.63-1 Date: Mon, 11 Jul 2016 12:28:47 -0000 From: Anna-Maria Gleixner To: LKML Cc: Peter Zijlstra , Ingo Molnar , Sebastian Andrzej Siewior , Gleb Natapov , Paolo Bonzini , kvm@vger.kernel.org, Anna-Maria Gleixner Subject: [patch 35/66] virt: Convert kvm hotplug to state machine References: <20160711122450.923603742@linutronix.de> MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-15 Content-Disposition: inline; filename=0029-virt-Convert-kvm-hotplug-to-state-machine.patch X-Linutronix-Spam-Score: -1.0 X-Linutronix-Spam-Level: - X-Linutronix-Spam-Status: No , -1.0 points, 5.0 required, ALL_TRUSTED=-1,SHORTCIRCUIT=-0.0001,URIBL_BLOCKED=0.001 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Thomas Gleixner Install the callbacks via the state machine. The core won't invoke the callbacks on already online CPUs. Signed-off-by: Thomas Gleixner Reviewed-by: Sebastian Andrzej Siewior Cc: Gleb Natapov Cc: Paolo Bonzini Cc: kvm@vger.kernel.org Signed-off-by: Anna-Maria Gleixner --- include/linux/cpuhotplug.h | 1 + virt/kvm/kvm_main.c | 32 ++++++++------------------------ 2 files changed, 9 insertions(+), 24 deletions(-) --- a/include/linux/cpuhotplug.h +++ b/include/linux/cpuhotplug.h @@ -37,6 +37,7 @@ enum cpuhp_state { CPUHP_AP_PERF_XTENSA_STARTING, CPUHP_AP_ARM_VFP_STARTING, CPUHP_AP_PERF_ARM_STARTING, + CPUHP_AP_KVM_STARTING, CPUHP_AP_NOTIFY_STARTING, CPUHP_AP_ONLINE, CPUHP_TEARDOWN_CPU, --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -3144,12 +3144,13 @@ static void hardware_enable_nolock(void } } -static void hardware_enable(void) +static int kvm_starting_cpu(unsigned int cpu) { raw_spin_lock(&kvm_count_lock); if (kvm_usage_count) hardware_enable_nolock(NULL); raw_spin_unlock(&kvm_count_lock); + return 0; } static void hardware_disable_nolock(void *junk) @@ -3162,12 +3163,13 @@ static void hardware_disable_nolock(void kvm_arch_hardware_disable(); } -static void hardware_disable(void) +static int kvm_dying_cpu(unsigned int cpu) { raw_spin_lock(&kvm_count_lock); if (kvm_usage_count) hardware_disable_nolock(NULL); raw_spin_unlock(&kvm_count_lock); + return 0; } static void hardware_disable_all_nolock(void) @@ -3208,21 +3210,6 @@ static int hardware_enable_all(void) return r; } -static int kvm_cpu_hotplug(struct notifier_block *notifier, unsigned long val, - void *v) -{ - val &= ~CPU_TASKS_FROZEN; - switch (val) { - case CPU_DYING: - hardware_disable(); - break; - case CPU_STARTING: - hardware_enable(); - break; - } - return NOTIFY_OK; -} - static int kvm_reboot(struct notifier_block *notifier, unsigned long val, void *v) { @@ -3489,10 +3476,6 @@ int kvm_io_bus_unregister_dev(struct kvm return r; } -static struct notifier_block kvm_cpu_notifier = { - .notifier_call = kvm_cpu_hotplug, -}; - static int kvm_debugfs_open(struct inode *inode, struct file *file, int (*get)(void *, u64 *), int (*set)(void *, u64), const char *fmt) @@ -3743,7 +3726,8 @@ int kvm_init(void *opaque, unsigned vcpu goto out_free_1; } - r = register_cpu_notifier(&kvm_cpu_notifier); + r = cpuhp_setup_state_nocalls(CPUHP_AP_KVM_STARTING, "AP_KVM_STARTING", + kvm_starting_cpu, kvm_dying_cpu); if (r) goto out_free_2; register_reboot_notifier(&kvm_reboot_notifier); @@ -3797,7 +3781,7 @@ int kvm_init(void *opaque, unsigned vcpu kmem_cache_destroy(kvm_vcpu_cache); out_free_3: unregister_reboot_notifier(&kvm_reboot_notifier); - unregister_cpu_notifier(&kvm_cpu_notifier); + cpuhp_remove_state_nocalls(CPUHP_AP_KVM_STARTING); out_free_2: out_free_1: kvm_arch_hardware_unsetup(); @@ -3820,7 +3804,7 @@ void kvm_exit(void) kvm_async_pf_deinit(); unregister_syscore_ops(&kvm_syscore_ops); unregister_reboot_notifier(&kvm_reboot_notifier); - unregister_cpu_notifier(&kvm_cpu_notifier); + cpuhp_remove_state_nocalls(CPUHP_AP_KVM_STARTING); on_each_cpu(hardware_disable_nolock, NULL, 1); kvm_arch_hardware_unsetup(); kvm_arch_exit();