KVM: x86/pmu: Move PMU reset logic to common x86 code

Move the common (or at least "ignored") aspects of resetting the vPMU to
common x86 code, along with the stop/release helpers that are no used only
by the common pmu.c.

There is no need to manually handle fixed counters as all_valid_pmc_idx
tracks both fixed and general purpose counters, and resetting the vPMU is
far from a hot path, i.e. the extra bit of overhead to the PMC from the
index is a non-issue.

Zero fixed_ctr_ctrl in common code even though it's Intel specific.
Ensuring it's zero doesn't harm AMD/SVM in any way, and stopping the fixed
counters via all_valid_pmc_idx, but not clearing the associated control
bits, would be odd/confusing.

Make the .reset() hook optional as SVM no longer needs vendor specific
handling.

Cc: stable@vger.kernel.org
Reviewed-by: Dapeng Mi <dapeng1.mi@linux.intel.com>
Link: https://lore.kernel.org/r/20231103230541.352265-2-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>

1 files changed, 0 insertions, 20 deletions

diff --git a/arch/x86/kvm/vmx/pmu_intel.c b/arch/x86/kvm/vmx/pmu_intel.c
index 820d3e1f6b4f..90c1f7f07e53 100644
--- a/arch/x86/kvm/vmx/pmu_intel.c
+++ b/arch/x86/kvm/vmx/pmu_intel.c
@@ -632,26 +632,6 @@ static void intel_pmu_init(struct kvm_vcpu *vcpu)
 
 static void intel_pmu_reset(struct kvm_vcpu *vcpu)
 {
-	struct kvm_pmu *pmu = vcpu_to_pmu(vcpu);
-	struct kvm_pmc *pmc = NULL;
-	int i;
-
-	for (i = 0; i < KVM_INTEL_PMC_MAX_GENERIC; i++) {
-		pmc = &pmu->gp_counters[i];
-
-		pmc_stop_counter(pmc);
-		pmc->counter = pmc->prev_counter = pmc->eventsel = 0;
-	}
-
-	for (i = 0; i < KVM_PMC_MAX_FIXED; i++) {
-		pmc = &pmu->fixed_counters[i];
-
-		pmc_stop_counter(pmc);
-		pmc->counter = pmc->prev_counter = 0;
-	}
-
-	pmu->fixed_ctr_ctrl = pmu->global_ctrl = pmu->global_status = 0;
-
 	intel_pmu_release_guest_lbr_event(vcpu);
 }