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Commit 103af0a9 authored by Andi Kleen's avatar Andi Kleen Committed by Paolo Bonzini
Browse files

perf, kvm: Support the in_tx/in_tx_cp modifiers in KVM arch perfmon emulation v5 



[KVM maintainers:
The underlying support for this is in perf/core now. So please merge
this patch into the KVM tree.]

This is not arch perfmon, but older CPUs will just ignore it. This makes
it possible to do at least some TSX measurements from a KVM guest

v2: Various fixes to address review feedback
v3: Ignore the bits when no CPUID. No #GP. Force raw events with TSX bits.
v4: Use reserved bits for #GP
v5: Remove obsolete argument
Acked-by: default avatarGleb Natapov <gleb@redhat.com>
Signed-off-by: default avatarAndi Kleen <ak@linux.intel.com>
Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent 21feb4eb

arch/x86/include/asm/kvm_host.h

+1 −0
Original line number Diff line number Diff line
@@ -323,6 +323,7 @@ struct kvm_pmu { 
	u64 global_ovf_ctrl;

	u64 counter_bitmask[2];

	u64 global_ctrl_mask;

	u64 reserved_bits;

	u8 version;

	struct kvm_pmc gp_counters[INTEL_PMC_MAX_GENERIC];

	struct kvm_pmc fixed_counters[INTEL_PMC_MAX_FIXED];

arch/x86/kvm/pmu.c

+20 −5
Original line number Diff line number Diff line
@@ -160,7 +160,7 @@ static void stop_counter(struct kvm_pmc *pmc) 


static void reprogram_counter(struct kvm_pmc *pmc, u32 type,

		unsigned config, bool exclude_user, bool exclude_kernel,

		bool intr)

		bool intr, bool in_tx, bool in_tx_cp)

{

	struct perf_event *event;

	struct perf_event_attr attr = {
@@ -173,6 +173,10 @@ static void reprogram_counter(struct kvm_pmc *pmc, u32 type, 
		.exclude_kernel = exclude_kernel,

		.config = config,

	};

	if (in_tx)

		attr.config |= HSW_IN_TX;

	if (in_tx_cp)

		attr.config |= HSW_IN_TX_CHECKPOINTED;



	attr.sample_period = (-pmc->counter) & pmc_bitmask(pmc);
@@ -226,7 +230,9 @@ static void reprogram_gp_counter(struct kvm_pmc *pmc, u64 eventsel) 


	if (!(eventsel & (ARCH_PERFMON_EVENTSEL_EDGE |

				ARCH_PERFMON_EVENTSEL_INV |

				ARCH_PERFMON_EVENTSEL_CMASK))) {

				ARCH_PERFMON_EVENTSEL_CMASK |

				HSW_IN_TX |

				HSW_IN_TX_CHECKPOINTED))) {

		config = find_arch_event(&pmc->vcpu->arch.pmu, event_select,

				unit_mask);

		if (config != PERF_COUNT_HW_MAX)
@@ -239,7 +245,9 @@ static void reprogram_gp_counter(struct kvm_pmc *pmc, u64 eventsel) 
	reprogram_counter(pmc, type, config,

			!(eventsel & ARCH_PERFMON_EVENTSEL_USR),

			!(eventsel & ARCH_PERFMON_EVENTSEL_OS),

			eventsel & ARCH_PERFMON_EVENTSEL_INT);

			eventsel & ARCH_PERFMON_EVENTSEL_INT,

			(eventsel & HSW_IN_TX),

			(eventsel & HSW_IN_TX_CHECKPOINTED));

}



static void reprogram_fixed_counter(struct kvm_pmc *pmc, u8 en_pmi, int idx)
@@ -256,7 +264,7 @@ static void reprogram_fixed_counter(struct kvm_pmc *pmc, u8 en_pmi, int idx) 
			arch_events[fixed_pmc_events[idx]].event_type,

			!(en & 0x2), /* exclude user */

			!(en & 0x1), /* exclude kernel */

			pmi);

			pmi, false, false);

}



static inline u8 fixed_en_pmi(u64 ctrl, int idx)
@@ -408,7 +416,7 @@ int kvm_pmu_set_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info) 
		} else if ((pmc = get_gp_pmc(pmu, index, MSR_P6_EVNTSEL0))) {

			if (data == pmc->eventsel)

				return 0;

			if (!(data & 0xffffffff00200000ull)) {

			if (!(data & pmu->reserved_bits)) {

				reprogram_gp_counter(pmc, data);

				return 0;

			}
@@ -450,6 +458,7 @@ void kvm_pmu_cpuid_update(struct kvm_vcpu *vcpu) 
	pmu->counter_bitmask[KVM_PMC_GP] = 0;

	pmu->counter_bitmask[KVM_PMC_FIXED] = 0;

	pmu->version = 0;

	pmu->reserved_bits = 0xffffffff00200000ull;



	entry = kvm_find_cpuid_entry(vcpu, 0xa, 0);

	if (!entry)
@@ -478,6 +487,12 @@ void kvm_pmu_cpuid_update(struct kvm_vcpu *vcpu) 
	pmu->global_ctrl = ((1 << pmu->nr_arch_gp_counters) - 1) |

		(((1ull << pmu->nr_arch_fixed_counters) - 1) << INTEL_PMC_IDX_FIXED);

	pmu->global_ctrl_mask = ~pmu->global_ctrl;



	entry = kvm_find_cpuid_entry(vcpu, 7, 0);

	if (entry &&

	    (boot_cpu_has(X86_FEATURE_HLE) || boot_cpu_has(X86_FEATURE_RTM)) &&

	    (entry->ebx & (X86_FEATURE_HLE|X86_FEATURE_RTM)))

		pmu->reserved_bits ^= HSW_IN_TX|HSW_IN_TX_CHECKPOINTED;

}



void kvm_pmu_init(struct kvm_vcpu *vcpu)