From: Srivatsa Vaddagiri <vatsa@xxxxxxxxxxxxxxxxxx> KVM_HC_KICK_CPU allows the calling vcpu to kick another vcpu out of halt state. The presence of these hypercalls is indicated to guest via KVM_FEATURE_PV_UNHALT/KVM_CAP_PV_UNHALT. Signed-off-by: Srivatsa Vaddagiri <vatsa@xxxxxxxxxxxxxxxxxx> Signed-off-by: Suzuki Poulose <suzuki@xxxxxxxxxx> Signed-off-by: Raghavendra K T <raghavendra.kt@xxxxxxxxxxxxxxxxxx> --- diff --git a/arch/x86/include/asm/kvm_para.h b/arch/x86/include/asm/kvm_para.h index 734c376..9234f13 100644 --- a/arch/x86/include/asm/kvm_para.h +++ b/arch/x86/include/asm/kvm_para.h @@ -16,12 +16,14 @@ #define KVM_FEATURE_CLOCKSOURCE 0 #define KVM_FEATURE_NOP_IO_DELAY 1 #define KVM_FEATURE_MMU_OP 2 + /* This indicates that the new set of kvmclock msrs * are available. The use of 0x11 and 0x12 is deprecated */ #define KVM_FEATURE_CLOCKSOURCE2 3 #define KVM_FEATURE_ASYNC_PF 4 #define KVM_FEATURE_STEAL_TIME 5 +#define KVM_FEATURE_PV_UNHALT 6 /* The last 8 bits are used to indicate how to interpret the flags field * in pvclock structure. If no bits are set, all flags are ignored. @@ -32,6 +34,7 @@ #define MSR_KVM_SYSTEM_TIME 0x12 #define KVM_MSR_ENABLED 1 + /* Custom MSRs falls in the range 0x4b564d00-0x4b564dff */ #define MSR_KVM_WALL_CLOCK_NEW 0x4b564d00 #define MSR_KVM_SYSTEM_TIME_NEW 0x4b564d01 diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c index 89b02bf..61388b9 100644 --- a/arch/x86/kvm/cpuid.c +++ b/arch/x86/kvm/cpuid.c @@ -408,7 +408,8 @@ static int do_cpuid_ent(struct kvm_cpuid_entry2 *entry, u32 function, (1 << KVM_FEATURE_NOP_IO_DELAY) | (1 << KVM_FEATURE_CLOCKSOURCE2) | (1 << KVM_FEATURE_ASYNC_PF) | - (1 << KVM_FEATURE_CLOCKSOURCE_STABLE_BIT); + (1 << KVM_FEATURE_CLOCKSOURCE_STABLE_BIT) | + (1 << KVM_FEATURE_PV_UNHALT); if (sched_info_on()) entry->eax |= (1 << KVM_FEATURE_STEAL_TIME); diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 9cbfc06..bd5ef91 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -2079,6 +2079,7 @@ int kvm_dev_ioctl_check_extension(long ext) case KVM_CAP_XSAVE: case KVM_CAP_ASYNC_PF: case KVM_CAP_GET_TSC_KHZ: + case KVM_CAP_PV_UNHALT: r = 1; break; case KVM_CAP_COALESCED_MMIO: @@ -4913,6 +4914,30 @@ int kvm_hv_hypercall(struct kvm_vcpu *vcpu) return 1; } +/* + * kvm_pv_kick_cpu_op: Kick a vcpu. + * + * @apicid - apicid of vcpu to be kicked. + */ +static void kvm_pv_kick_cpu_op(struct kvm *kvm, int apicid) +{ + struct kvm_vcpu *vcpu = NULL; + int i; + + kvm_for_each_vcpu(i, vcpu, kvm) { + if (!kvm_apic_present(vcpu)) + continue; + + if (kvm_apic_match_dest(vcpu, 0, 0, apicid, 0)) + break; + } + if (vcpu) { + vcpu->pv_unhalted = 1; + smp_mb(); + kvm_vcpu_kick(vcpu); + } +} + int kvm_emulate_hypercall(struct kvm_vcpu *vcpu) { unsigned long nr, a0, a1, a2, a3, ret; @@ -4946,6 +4971,10 @@ int kvm_emulate_hypercall(struct kvm_vcpu *vcpu) case KVM_HC_VAPIC_POLL_IRQ: ret = 0; break; + case KVM_HC_KICK_CPU: + kvm_pv_kick_cpu_op(vcpu->kvm, a0); + ret = 0; + break; default: ret = -KVM_ENOSYS; break; @@ -6174,6 +6203,7 @@ int kvm_arch_vcpu_runnable(struct kvm_vcpu *vcpu) !vcpu->arch.apf.halted) || !list_empty_careful(&vcpu->async_pf.done) || vcpu->arch.mp_state == KVM_MP_STATE_SIPI_RECEIVED + || vcpu->pv_unhalted || atomic_read(&vcpu->arch.nmi_queued) || (kvm_arch_interrupt_allowed(vcpu) && kvm_cpu_has_interrupt(vcpu)); diff --git a/include/linux/kvm.h b/include/linux/kvm.h index 68e67e5..e822d96 100644 --- a/include/linux/kvm.h +++ b/include/linux/kvm.h @@ -558,6 +558,7 @@ struct kvm_ppc_pvinfo { #define KVM_CAP_PPC_PAPR 68 #define KVM_CAP_S390_GMAP 71 #define KVM_CAP_TSC_DEADLINE_TIMER 72 +#define KVM_CAP_PV_UNHALT 73 #ifdef KVM_CAP_IRQ_ROUTING diff --git a/include/linux/kvm_host.h b/include/linux/kvm_host.h index 900c763..433ae97 100644 --- a/include/linux/kvm_host.h +++ b/include/linux/kvm_host.h @@ -158,6 +158,7 @@ struct kvm_vcpu { #endif struct kvm_vcpu_arch arch; + int pv_unhalted; }; static inline int kvm_vcpu_exiting_guest_mode(struct kvm_vcpu *vcpu) diff --git a/include/linux/kvm_para.h b/include/linux/kvm_para.h index ff476dd..38226e1 100644 --- a/include/linux/kvm_para.h +++ b/include/linux/kvm_para.h @@ -19,6 +19,7 @@ #define KVM_HC_MMU_OP 2 #define KVM_HC_FEATURES 3 #define KVM_HC_PPC_MAP_MAGIC_PAGE 4 +#define KVM_HC_KICK_CPU 5 /* * hypercalls use architecture specific diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index a91f980..d3b98b1 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -226,6 +226,7 @@ int kvm_vcpu_init(struct kvm_vcpu *vcpu, struct kvm *kvm, unsigned id) vcpu->kvm = kvm; vcpu->vcpu_id = id; vcpu->pid = NULL; + vcpu->pv_unhalted = 0; init_waitqueue_head(&vcpu->wq); kvm_async_pf_vcpu_init(vcpu); @@ -1567,6 +1568,9 @@ void kvm_vcpu_block(struct kvm_vcpu *vcpu) prepare_to_wait(&vcpu->wq, &wait, TASK_INTERRUPTIBLE); if (kvm_arch_vcpu_runnable(vcpu)) { + vcpu->pv_unhalted = 0; + /* preventing reordering should be enough here */ + barrier(); kvm_make_request(KVM_REQ_UNHALT, vcpu); break; } -- To unsubscribe from this list: send the line "unsubscribe linux-doc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html