Wanpeng Li <kernellwp@xxxxxxxxx> writes:
> From: Wanpeng Li <wanpengli@xxxxxxxxxxx>
>
> Implement PV IPIs in guest kernel.
>
> Cc: Paolo Bonzini <pbonzini@xxxxxxxxxx>
> Cc: Radim Krčmář <rkrcmar@xxxxxxxxxx>
> Cc: Vitaly Kuznetsov <vkuznets@xxxxxxxxxx>
> Signed-off-by: Wanpeng Li <wanpengli@xxxxxxxxxxx>
> ---
> arch/x86/include/uapi/asm/kvm_para.h | 1 +
> arch/x86/kernel/kvm.c | 63 ++++++++++++++++++++++++++++++++++++
> 2 files changed, 64 insertions(+)
>
> diff --git a/arch/x86/include/uapi/asm/kvm_para.h b/arch/x86/include/uapi/asm/kvm_para.h
> index 0ede697..19980ec 100644
> --- a/arch/x86/include/uapi/asm/kvm_para.h
> +++ b/arch/x86/include/uapi/asm/kvm_para.h
> @@ -28,6 +28,7 @@
> #define KVM_FEATURE_PV_UNHALT 7
> #define KVM_FEATURE_PV_TLB_FLUSH 9
> #define KVM_FEATURE_ASYNC_PF_VMEXIT 10
> +#define KVM_FEATURE_PV_SEND_IPI 11
>
> #define KVM_HINTS_REALTIME 0
>
> diff --git a/arch/x86/kernel/kvm.c b/arch/x86/kernel/kvm.c
> index 5b2300b..b4f8dc3 100644
> --- a/arch/x86/kernel/kvm.c
> +++ b/arch/x86/kernel/kvm.c
> @@ -454,6 +454,57 @@ static void __init sev_map_percpu_data(void)
> }
>
> #ifdef CONFIG_SMP
> +
> +static void __send_ipi_mask(const struct cpumask *mask, int vector)
> +{
> + unsigned long flags, ipi_bitmap = 0;
> + int cpu;
> +
> + local_irq_save(flags);
> +
> + for_each_cpu(cpu, mask)
> + __set_bit(per_cpu(x86_cpu_to_apicid, cpu), &ipi_bitmap);
We need a protection against per_cpu(x86_cpu_to_apicid, cpu) > here.
> + kvm_hypercall2(KVM_HC_SEND_IPI, ipi_bitmap, vector);
> +
> + local_irq_restore(flags);
> +}
> +
> +static void kvm_send_ipi_mask(const struct cpumask *mask, int vector)
> +{
> + __send_ipi_mask(mask, vector);
> +}
> +
> +static void kvm_send_ipi_mask_allbutself(const struct cpumask *mask, int vector)
> +{
> + unsigned int this_cpu = smp_processor_id();
> + struct cpumask new_mask;
> + const struct cpumask *local_mask;
> +
> + cpumask_copy(&new_mask, mask);
> + cpumask_clear_cpu(this_cpu, &new_mask);
> + local_mask = &new_mask;
> + __send_ipi_mask(local_mask, vector);
> +}
> +
> +static void kvm_send_ipi_allbutself(int vector)
> +{
> + kvm_send_ipi_mask_allbutself(cpu_online_mask, vector);
> +}
> +
> +static void kvm_send_ipi_all(int vector)
> +{
> + __send_ipi_mask(cpu_online_mask, vector);
> +}
> +
> +static void kvm_setup_pv_ipi(void)
> +{
> + apic->send_IPI_mask = kvm_send_ipi_mask;
> + apic->send_IPI_mask_allbutself = kvm_send_ipi_mask_allbutself;
> + apic->send_IPI_allbutself = kvm_send_ipi_allbutself;
> + apic->send_IPI_all = kvm_send_ipi_all;
> + printk("KVM setup pv IPIs\n");
> +}
> +
> static void __init kvm_smp_prepare_cpus(unsigned int max_cpus)
> {
> native_smp_prepare_cpus(max_cpus);
> @@ -624,12 +675,24 @@ static uint32_t __init kvm_detect(void)
> return kvm_cpuid_base();
> }
>
> +static void __init kvm_apic_init(void)
> +{
> + if (kvm_para_has_feature(KVM_FEATURE_PV_SEND_IPI))
> + kvm_setup_pv_ipi();
> +}
> +
> +static void __init kvm_init_platform(void)
> +{
> + x86_platform.apic_post_init = kvm_apic_init;
> +}
> +
> const __initconst struct hypervisor_x86 x86_hyper_kvm = {
> .name = "KVM",
> .detect = kvm_detect,
> .type = X86_HYPER_KVM,
> .init.guest_late_init = kvm_guest_init,
> .init.x2apic_available = kvm_para_available,
> + .init.init_platform = kvm_init_platform,
> };
>
> static __init int activate_jump_labels(void)
--
Vitaly
