[PATCH v3 7/9] perf/x86/intel: KVM: Handle cross-mapped PEBS PMCs entirely within KVM

[Sean Christopherson]

Now that perf operates on a KVM-provided snapshot of PMU state, handled
cross-mapped PEBS counters entirely in KVM by clearing unusable counters
from the to-be-enabled mask instead of foisting the work on perf.

No functional change intended.

Signed-off-by: Sean Christopherson <seanjc@xxxxxxxxxx>
---
 arch/x86/events/intel/core.c      |  8 --------
 arch/x86/include/asm/perf_event.h |  1 -
 arch/x86/kvm/vmx/vmx.c            | 10 ++++++++--
 3 files changed, 8 insertions(+), 11 deletions(-)

diff --git a/arch/x86/events/intel/core.c b/arch/x86/events/intel/core.c
index e9acfc3f3a82..8f6be0cc4c4b 100644
--- a/arch/x86/events/intel/core.c
+++ b/arch/x86/events/intel/core.c
@@ -5053,14 +5053,6 @@ static struct perf_guest_switch_msr *intel_guest_get_msrs(int *nr,
 			  ~cpuc->intel_ctrl_exclude_guest_mask &
 			  cpuc->intel_ctrl_exclude_host_mask;
 
-	/*
-	 * Disable counters where the guest PMC is different than the host PMC
-	 * being used on behalf of the guest, as the PEBS record includes
-	 * PERF_GLOBAL_STATUS, i.e. the guest will see overflow status for the
-	 * wrong counter(s).
-	 */
-	guest_pebs_mask &= ~guest_pebs->cross_mapped_mask;
-
 	/*
 	 * FIXME: Allow guest and host usage of PEBS events to co-exist instead
 	 *        of disabling guest PEBS entirely if the host is using PEBS.
diff --git a/arch/x86/include/asm/perf_event.h b/arch/x86/include/asm/perf_event.h
index bc7e48f6f4a8..19f874a79ab0 100644
--- a/arch/x86/include/asm/perf_event.h
+++ b/arch/x86/include/asm/perf_event.h
@@ -790,7 +790,6 @@ struct x86_guest_pebs {
 	u64	enable;
 	u64	ds_area;
 	u64	data_cfg;
-	u64	cross_mapped_mask;
 };
 #if defined(CONFIG_PERF_EVENTS) && defined(CONFIG_CPU_SUP_INTEL)
 extern struct perf_guest_switch_msr *perf_guest_get_msrs(int *nr,
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index 9f0a028cf10b..fbe3ce5f5a51 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -7319,8 +7319,14 @@ static void atomic_switch_perf_msrs(struct vcpu_vmx *vmx)
 		.data_cfg = pmu->pebs_data_cfg,
 	};
 
-	if (pmu->pebs_enable & pmu->global_ctrl)
-		guest_pebs.cross_mapped_mask = intel_pmu_get_cross_mapped_mask(pmu);
+	/*
+	 * Disable counters where the guest PMC is different than the host PMC
+	 * being used on behalf of the guest, as the PEBS record includes
+	 * PERF_GLOBAL_STATUS, i.e. the guest will see overflow status for the
+	 * wrong counter(s).
+	 */
+	if (guest_pebs.enable & pmu->global_ctrl)
+		guest_pebs.enable &= ~intel_pmu_get_cross_mapped_mask(pmu);
 
 	/* Note, nr_msrs may be garbage if perf_guest_get_msrs() returns NULL. */
 	msrs = perf_guest_get_msrs(&nr_msrs, &guest_pebs);
-- 
2.54.0.563.g4f69b47b94-goog