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Subject[PATCH 2/7] KVM: x86/pmu: Fix available_event_types check for REF_CPU_CYCLES event
Date
From: Like Xu <likexu@tencent.com>

For the CPUID 0x0A.EBX bit vector, the [7] event should be the Intel
unrealized architectural performance events "Topdown Slots" instead
of the *kernel* generalized common hardware event "REF_CPU_CYCLES", so
we can skip the cpuid unavaliblity check in the intel_find_arch_event()
for the last REF_CPU_CYCLES event and update the confusing comment.

Fixes: 62079d8a43128 ("KVM: PMU: add proper support for fixed counter 2")
Signed-off-by: Like Xu <likexu@tencent.com>
---
arch/x86/kvm/vmx/pmu_intel.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/arch/x86/kvm/vmx/pmu_intel.c b/arch/x86/kvm/vmx/pmu_intel.c
index b8e0d21b7c8a..bc6845265362 100644
--- a/arch/x86/kvm/vmx/pmu_intel.c
+++ b/arch/x86/kvm/vmx/pmu_intel.c
@@ -21,7 +21,6 @@
#define MSR_PMC_FULL_WIDTH_BIT (MSR_IA32_PMC0 - MSR_IA32_PERFCTR0)

static struct kvm_event_hw_type_mapping intel_arch_events[] = {
- /* Index must match CPUID 0x0A.EBX bit vector */
[0] = { 0x3c, 0x00, PERF_COUNT_HW_CPU_CYCLES },
[1] = { 0xc0, 0x00, PERF_COUNT_HW_INSTRUCTIONS },
[2] = { 0x3c, 0x01, PERF_COUNT_HW_BUS_CYCLES },
@@ -29,6 +28,7 @@ static struct kvm_event_hw_type_mapping intel_arch_events[] = {
[4] = { 0x2e, 0x41, PERF_COUNT_HW_CACHE_MISSES },
[5] = { 0xc4, 0x00, PERF_COUNT_HW_BRANCH_INSTRUCTIONS },
[6] = { 0xc5, 0x00, PERF_COUNT_HW_BRANCH_MISSES },
+ /* The above index must match CPUID 0x0A.EBX bit vector */
[7] = { 0x00, 0x03, PERF_COUNT_HW_REF_CPU_CYCLES },
};

@@ -75,9 +75,9 @@ static unsigned intel_find_arch_event(struct kvm_pmu *pmu,
int i;

for (i = 0; i < ARRAY_SIZE(intel_arch_events); i++)
- if (intel_arch_events[i].eventsel == event_select
- && intel_arch_events[i].unit_mask == unit_mask
- && (pmu->available_event_types & (1 << i)))
+ if (intel_arch_events[i].eventsel == event_select &&
+ intel_arch_events[i].unit_mask == unit_mask &&
+ ((i > 6) || pmu->available_event_types & (1 << i)))
break;

if (i == ARRAY_SIZE(intel_arch_events))
--
2.33.0
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