| Message ID | 20160818125731.27256-15-bigeasy@linutronix.de (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On 18/08/2016 14:57, Sebastian Andrzej Siewior wrote: > 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 <gleb@kernel.org> > Cc: Paolo Bonzini <pbonzini@redhat.com> > Cc: kvm@vger.kernel.org > Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> > --- > 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 > Reviewed-by: Paolo Bonzini <pbonzini@redhat.com> -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
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
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 <gleb@kernel.org> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: kvm@vger.kernel.org Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> --- arch/x86/kernel/kvm.c | 42 +++++++++++++++--------------------------- 1 file changed, 15 insertions(+), 27 deletions(-)