Enable async PF in a guest if async PF capability is discovered. Signed-off-by: Gleb Natapov <gleb@xxxxxxxxxx> --- arch/x86/include/asm/kvm_para.h | 5 +++ arch/x86/kernel/kvm.c | 68 +++++++++++++++++++++++++++++++++++++++ 2 files changed, 73 insertions(+), 0 deletions(-) diff --git a/arch/x86/include/asm/kvm_para.h b/arch/x86/include/asm/kvm_para.h index 5b05e9f..f1662d7 100644 --- a/arch/x86/include/asm/kvm_para.h +++ b/arch/x86/include/asm/kvm_para.h @@ -65,6 +65,11 @@ struct kvm_mmu_op_release_pt { __u64 pt_phys; }; +struct kvm_vcpu_pv_apf_data { + __u32 reason; + __u32 enabled; +}; + #ifdef __KERNEL__ #include <asm/processor.h> diff --git a/arch/x86/kernel/kvm.c b/arch/x86/kernel/kvm.c index e6db179..5177dd1 100644 --- a/arch/x86/kernel/kvm.c +++ b/arch/x86/kernel/kvm.c @@ -27,7 +27,10 @@ #include <linux/mm.h> #include <linux/highmem.h> #include <linux/hardirq.h> +#include <linux/notifier.h> +#include <linux/reboot.h> #include <asm/timer.h> +#include <asm/cpu.h> #define MMU_QUEUE_SIZE 1024 @@ -37,6 +40,7 @@ struct kvm_para_state { }; static DEFINE_PER_CPU(struct kvm_para_state, para_state); +static DEFINE_PER_CPU(struct kvm_vcpu_pv_apf_data, apf_reason) __aligned(64); static struct kvm_para_state *kvm_para_state(void) { @@ -231,12 +235,72 @@ static void __init paravirt_ops_setup(void) #endif } +void __cpuinit kvm_guest_cpu_init(void) +{ + if (!kvm_para_available()) + return; + + if (kvm_para_has_feature(KVM_FEATURE_ASYNC_PF)) { + u64 pa = __pa(&__get_cpu_var(apf_reason)); + + if (native_write_msr_safe(MSR_KVM_ASYNC_PF_EN, + pa | KVM_ASYNC_PF_ENABLED, pa >> 32)) + return; + __get_cpu_var(apf_reason).enabled = 1; + printk(KERN_INFO"KVM setup async PF for cpu %d\n", + smp_processor_id()); + } +} + +static void kvm_pv_disable_apf(void *unused) +{ + if (!__get_cpu_var(apf_reason).enabled) + return; + + wrmsrl(MSR_KVM_ASYNC_PF_EN, 0); + __get_cpu_var(apf_reason).enabled = 0; + + printk(KERN_INFO"Unregister pv shared memory for cpu %d\n", + smp_processor_id()); +} + +static int kvm_pv_reboot_notify(struct notifier_block *nb, + unsigned long code, void *unused) +{ + if (code == SYS_RESTART) + on_each_cpu(kvm_pv_disable_apf, NULL, 1); + return NOTIFY_DONE; +} + +static struct notifier_block kvm_pv_reboot_nb = { + .notifier_call = kvm_pv_reboot_notify, +}; + #ifdef CONFIG_SMP static void __init kvm_smp_prepare_boot_cpu(void) { WARN_ON(kvm_register_clock("primary cpu clock")); + kvm_guest_cpu_init(); native_smp_prepare_boot_cpu(); } + +static int __cpuinit kvm_cpu_notify(struct notifier_block *self, + unsigned long action, void *hcpu) +{ + switch (action) { + case CPU_ONLINE: + case CPU_ONLINE_FROZEN: + kvm_guest_cpu_init(); + break; + default: + break; + } + return NOTIFY_OK; +} + +static struct notifier_block __cpuinitdata kvm_cpu_notifier = { + .notifier_call = kvm_cpu_notify, +}; #endif void __init kvm_guest_init(void) @@ -245,7 +309,11 @@ void __init kvm_guest_init(void) return; paravirt_ops_setup(); + register_reboot_notifier(&kvm_pv_reboot_nb); #ifdef CONFIG_SMP smp_ops.smp_prepare_boot_cpu = kvm_smp_prepare_boot_cpu; + register_cpu_notifier(&kvm_cpu_notifier); +#else + kvm_guest_cpu_init(); #endif } -- 1.7.1 -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html