arm64: KVM: Add PMU overflow interrupt routing

When calling perf_event_create_kernel_counter to create perf_event,
assign a overflow handler. Then when the perf event overflows, set the
corresponding bit of guest PMOVSSET register. If this counter is enabled
and its interrupt is enabled as well, kick the vcpu to sync the
interrupt.

On VM entry, if there is counter overflowed and interrupt level is
changed, inject the interrupt with corresponding level. On VM exit, sync
the interrupt level as well if it has been changed.

Signed-off-by: Shannon Zhao <shannon.zhao@linaro.org>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Reviewed-by: Andrew Jones <drjones@redhat.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

1 files changed, 6 insertions, 2 deletions

diff --git a/arch/arm/kvm/arm.c b/arch/arm/kvm/arm.c
index 686350d05174..c5e959187abd 100644
--- a/arch/arm/kvm/arm.c
+++ b/arch/arm/kvm/arm.c
@@ -28,6 +28,7 @@
 #include <linux/sched.h>
 #include <linux/kvm.h>
 #include <trace/events/kvm.h>
+#include <kvm/arm_pmu.h>
 
 #define CREATE_TRACE_POINTS
 #include "trace.h"
@@ -577,6 +578,7 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *run)
                  * non-preemptible context.
                  */
                 preempt_disable();
+                kvm_pmu_flush_hwstate(vcpu);
                 kvm_timer_flush_hwstate(vcpu);
                 kvm_vgic_flush_hwstate(vcpu);
 
@@ -593,6 +595,7 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *run)
                 if (ret <= 0 || need_new_vmid_gen(vcpu->kvm) ||
                         vcpu->arch.power_off || vcpu->arch.pause) {
                         local_irq_enable();
+                        kvm_pmu_sync_hwstate(vcpu);
                         kvm_timer_sync_hwstate(vcpu);
                         kvm_vgic_sync_hwstate(vcpu);
                         preempt_enable();
@@ -642,10 +645,11 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *run)
                 trace_kvm_exit(ret, kvm_vcpu_trap_get_class(vcpu), *vcpu_pc(vcpu));
 
                 /*
-                 * We must sync the timer state before the vgic state so that
-                 * the vgic can properly sample the updated state of the
+                 * We must sync the PMU and timer state before the vgic state so
+                 * that the vgic can properly sample the updated state of the
                  * interrupt line.
                  */
+                kvm_pmu_sync_hwstate(vcpu);
                 kvm_timer_sync_hwstate(vcpu);
 
                 kvm_vgic_sync_hwstate(vcpu);