[PATCH 05/32] perf, kvm: Support the intx/intx_cp modifiers in KVM arch perfmon emulation v3

[Andi Kleen]

From: Andi Kleen <ak@xxxxxxxxxxxxxxx>

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

Cc: avi@xxxxxxxxxx
Cc: gleb@xxxxxxxxxx
v2: Various fixes to address review feedback
v3: Ignore the bits when no CPUID. No #GP. Force raw events with TSX bits.
Cc: gleb@xxxxxxxxxx
Signed-off-by: Andi Kleen <ak@xxxxxxxxxxxxxxx>
---
 arch/x86/include/asm/kvm_host.h |    1 +
 arch/x86/kvm/pmu.c              |   34 ++++++++++++++++++++++++++--------
 2 files changed, 27 insertions(+), 8 deletions(-)

diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index b2e11f4..6783289 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -318,6 +318,7 @@ struct kvm_pmu {
 	u64 global_ovf_ctrl;
 	u64 counter_bitmask[2];
 	u64 global_ctrl_mask;
+	u64 cpuid_word9;
 	u8 version;
 	struct kvm_pmc gp_counters[INTEL_PMC_MAX_GENERIC];
 	struct kvm_pmc fixed_counters[INTEL_PMC_MAX_FIXED];
diff --git a/arch/x86/kvm/pmu.c b/arch/x86/kvm/pmu.c
index cfc258a..8bc954a 100644
--- a/arch/x86/kvm/pmu.c
+++ b/arch/x86/kvm/pmu.c
@@ -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 intx, bool intx_cp)
 {
 	struct perf_event *event;
 	struct perf_event_attr attr = {
@@ -173,6 +173,11 @@ static void reprogram_counter(struct kvm_pmc *pmc, u32 type,
 		.exclude_kernel = exclude_kernel,
 		.config = config,
 	};
+	/* Will be ignored on CPUs that don't support this. */
+	if (intx)
+		attr.config |= HSW_INTX;
+	if (intx_cp)
+		attr.config |= HSW_INTX_CHECKPOINTED;
 
 	attr.sample_period = (-pmc->counter) & pmc_bitmask(pmc);
 
@@ -206,7 +211,8 @@ static unsigned find_arch_event(struct kvm_pmu *pmu, u8 event_select,
 	return arch_events[i].event_type;
 }
 
-static void reprogram_gp_counter(struct kvm_pmc *pmc, u64 eventsel)
+static void reprogram_gp_counter(struct kvm_pmu *pmu, struct kvm_pmc *pmc, 
+				 u64 eventsel)
 {
 	unsigned config, type = PERF_TYPE_RAW;
 	u8 event_select, unit_mask;
@@ -224,9 +230,16 @@ static void reprogram_gp_counter(struct kvm_pmc *pmc, u64 eventsel)
 	event_select = eventsel & ARCH_PERFMON_EVENTSEL_EVENT;
 	unit_mask = (eventsel & ARCH_PERFMON_EVENTSEL_UMASK) >> 8;
 
+	if (!(boot_cpu_has(X86_FEATURE_HLE) ||
+	      boot_cpu_has(X86_FEATURE_RTM)) ||
+	    !(pmu->cpuid_word9 & (X86_FEATURE_HLE|X86_FEATURE_RTM)))
+		eventsel &= ~(HSW_INTX|HSW_INTX_CHECKPOINTED);
+
 	if (!(eventsel & (ARCH_PERFMON_EVENTSEL_EDGE |
 				ARCH_PERFMON_EVENTSEL_INV |
-				ARCH_PERFMON_EVENTSEL_CMASK))) {
+				ARCH_PERFMON_EVENTSEL_CMASK |
+				HSW_INTX |
+				HSW_INTX_CHECKPOINTED))) {
 		config = find_arch_event(&pmc->vcpu->arch.pmu, event_select,
 				unit_mask);
 		if (config != PERF_COUNT_HW_MAX)
@@ -239,7 +252,9 @@ 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_INTX),
+			(eventsel & HSW_INTX_CHECKPOINTED));
 }
 
 static void reprogram_fixed_counter(struct kvm_pmc *pmc, u8 en_pmi, int idx)
@@ -256,7 +271,7 @@ 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)
@@ -289,7 +304,7 @@ static void reprogram_idx(struct kvm_pmu *pmu, int idx)
 		return;
 
 	if (pmc_is_gp(pmc))
-		reprogram_gp_counter(pmc, pmc->eventsel);
+		reprogram_gp_counter(pmu, pmc, pmc->eventsel);
 	else {
 		int fidx = idx - INTEL_PMC_IDX_FIXED;
 		reprogram_fixed_counter(pmc,
@@ -400,8 +415,8 @@ int kvm_pmu_set_msr(struct kvm_vcpu *vcpu, u32 index, u64 data)
 		} else if ((pmc = get_gp_pmc(pmu, index, MSR_P6_EVNTSEL0))) {
 			if (data == pmc->eventsel)
 				return 0;
-			if (!(data & 0xffffffff00200000ull)) {
-				reprogram_gp_counter(pmc, data);
+			if (!(data & 0xfffffffc00200000ull)) {
+				reprogram_gp_counter(pmu, pmc, data);
 				return 0;
 			}
 		}
@@ -470,6 +485,9 @@ 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);
+	pmu->cpuid_word9 = entry ? entry->ebx : 0;
 }
 
 void kvm_pmu_init(struct kvm_vcpu *vcpu)
-- 
1.7.7.6

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