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Diffstat (limited to 'arch/x86/kvm/pmu_amd.c')
-rw-r--r--arch/x86/kvm/pmu_amd.c207
1 files changed, 207 insertions, 0 deletions
diff --git a/arch/x86/kvm/pmu_amd.c b/arch/x86/kvm/pmu_amd.c
new file mode 100644
index 000000000..886aa25a7
--- /dev/null
+++ b/arch/x86/kvm/pmu_amd.c
@@ -0,0 +1,207 @@
+/*
+ * KVM PMU support for AMD
+ *
+ * Copyright 2015, Red Hat, Inc. and/or its affiliates.
+ *
+ * Author:
+ * Wei Huang <wei@redhat.com>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2. See
+ * the COPYING file in the top-level directory.
+ *
+ * Implementation is based on pmu_intel.c file
+ */
+#include <linux/types.h>
+#include <linux/kvm_host.h>
+#include <linux/perf_event.h>
+#include "x86.h"
+#include "cpuid.h"
+#include "lapic.h"
+#include "pmu.h"
+
+/* duplicated from amd_perfmon_event_map, K7 and above should work. */
+static struct kvm_event_hw_type_mapping amd_event_mapping[] = {
+ [0] = { 0x76, 0x00, PERF_COUNT_HW_CPU_CYCLES },
+ [1] = { 0xc0, 0x00, PERF_COUNT_HW_INSTRUCTIONS },
+ [2] = { 0x80, 0x00, PERF_COUNT_HW_CACHE_REFERENCES },
+ [3] = { 0x81, 0x00, PERF_COUNT_HW_CACHE_MISSES },
+ [4] = { 0xc2, 0x00, PERF_COUNT_HW_BRANCH_INSTRUCTIONS },
+ [5] = { 0xc3, 0x00, PERF_COUNT_HW_BRANCH_MISSES },
+ [6] = { 0xd0, 0x00, PERF_COUNT_HW_STALLED_CYCLES_FRONTEND },
+ [7] = { 0xd1, 0x00, PERF_COUNT_HW_STALLED_CYCLES_BACKEND },
+};
+
+static unsigned amd_find_arch_event(struct kvm_pmu *pmu,
+ u8 event_select,
+ u8 unit_mask)
+{
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(amd_event_mapping); i++)
+ if (amd_event_mapping[i].eventsel == event_select
+ && amd_event_mapping[i].unit_mask == unit_mask)
+ break;
+
+ if (i == ARRAY_SIZE(amd_event_mapping))
+ return PERF_COUNT_HW_MAX;
+
+ return amd_event_mapping[i].event_type;
+}
+
+/* return PERF_COUNT_HW_MAX as AMD doesn't have fixed events */
+static unsigned amd_find_fixed_event(int idx)
+{
+ return PERF_COUNT_HW_MAX;
+}
+
+/* check if a PMC is enabled by comparing it against global_ctrl bits. Because
+ * AMD CPU doesn't have global_ctrl MSR, all PMCs are enabled (return TRUE).
+ */
+static bool amd_pmc_is_enabled(struct kvm_pmc *pmc)
+{
+ return true;
+}
+
+static struct kvm_pmc *amd_pmc_idx_to_pmc(struct kvm_pmu *pmu, int pmc_idx)
+{
+ return get_gp_pmc(pmu, MSR_K7_EVNTSEL0 + pmc_idx, MSR_K7_EVNTSEL0);
+}
+
+/* returns 0 if idx's corresponding MSR exists; otherwise returns 1. */
+static int amd_is_valid_msr_idx(struct kvm_vcpu *vcpu, unsigned idx)
+{
+ struct kvm_pmu *pmu = vcpu_to_pmu(vcpu);
+
+ idx &= ~(3u << 30);
+
+ return (idx >= pmu->nr_arch_gp_counters);
+}
+
+/* idx is the ECX register of RDPMC instruction */
+static struct kvm_pmc *amd_msr_idx_to_pmc(struct kvm_vcpu *vcpu, unsigned idx)
+{
+ struct kvm_pmu *pmu = vcpu_to_pmu(vcpu);
+ struct kvm_pmc *counters;
+
+ idx &= ~(3u << 30);
+ if (idx >= pmu->nr_arch_gp_counters)
+ return NULL;
+ counters = pmu->gp_counters;
+
+ return &counters[idx];
+}
+
+static bool amd_is_valid_msr(struct kvm_vcpu *vcpu, u32 msr)
+{
+ struct kvm_pmu *pmu = vcpu_to_pmu(vcpu);
+ int ret = false;
+
+ ret = get_gp_pmc(pmu, msr, MSR_K7_PERFCTR0) ||
+ get_gp_pmc(pmu, msr, MSR_K7_EVNTSEL0);
+
+ return ret;
+}
+
+static int amd_pmu_get_msr(struct kvm_vcpu *vcpu, u32 msr, u64 *data)
+{
+ struct kvm_pmu *pmu = vcpu_to_pmu(vcpu);
+ struct kvm_pmc *pmc;
+
+ /* MSR_K7_PERFCTRn */
+ pmc = get_gp_pmc(pmu, msr, MSR_K7_PERFCTR0);
+ if (pmc) {
+ *data = pmc_read_counter(pmc);
+ return 0;
+ }
+ /* MSR_K7_EVNTSELn */
+ pmc = get_gp_pmc(pmu, msr, MSR_K7_EVNTSEL0);
+ if (pmc) {
+ *data = pmc->eventsel;
+ return 0;
+ }
+
+ return 1;
+}
+
+static int amd_pmu_set_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
+{
+ struct kvm_pmu *pmu = vcpu_to_pmu(vcpu);
+ struct kvm_pmc *pmc;
+ u32 msr = msr_info->index;
+ u64 data = msr_info->data;
+
+ /* MSR_K7_PERFCTRn */
+ pmc = get_gp_pmc(pmu, msr, MSR_K7_PERFCTR0);
+ if (pmc) {
+ if (!msr_info->host_initiated)
+ data = (s64)data;
+ pmc->counter += data - pmc_read_counter(pmc);
+ return 0;
+ }
+ /* MSR_K7_EVNTSELn */
+ pmc = get_gp_pmc(pmu, msr, MSR_K7_EVNTSEL0);
+ if (pmc) {
+ if (data == pmc->eventsel)
+ return 0;
+ if (!(data & pmu->reserved_bits)) {
+ reprogram_gp_counter(pmc, data);
+ return 0;
+ }
+ }
+
+ return 1;
+}
+
+static void amd_pmu_refresh(struct kvm_vcpu *vcpu)
+{
+ struct kvm_pmu *pmu = vcpu_to_pmu(vcpu);
+
+ pmu->nr_arch_gp_counters = AMD64_NUM_COUNTERS;
+ pmu->counter_bitmask[KVM_PMC_GP] = ((u64)1 << 48) - 1;
+ pmu->reserved_bits = 0xffffffff00200000ull;
+ /* not applicable to AMD; but clean them to prevent any fall out */
+ pmu->counter_bitmask[KVM_PMC_FIXED] = 0;
+ pmu->nr_arch_fixed_counters = 0;
+ pmu->version = 0;
+ pmu->global_status = 0;
+}
+
+static void amd_pmu_init(struct kvm_vcpu *vcpu)
+{
+ struct kvm_pmu *pmu = vcpu_to_pmu(vcpu);
+ int i;
+
+ for (i = 0; i < AMD64_NUM_COUNTERS ; i++) {
+ pmu->gp_counters[i].type = KVM_PMC_GP;
+ pmu->gp_counters[i].vcpu = vcpu;
+ pmu->gp_counters[i].idx = i;
+ }
+}
+
+static void amd_pmu_reset(struct kvm_vcpu *vcpu)
+{
+ struct kvm_pmu *pmu = vcpu_to_pmu(vcpu);
+ int i;
+
+ for (i = 0; i < AMD64_NUM_COUNTERS; i++) {
+ struct kvm_pmc *pmc = &pmu->gp_counters[i];
+
+ pmc_stop_counter(pmc);
+ pmc->counter = pmc->eventsel = 0;
+ }
+}
+
+struct kvm_pmu_ops amd_pmu_ops = {
+ .find_arch_event = amd_find_arch_event,
+ .find_fixed_event = amd_find_fixed_event,
+ .pmc_is_enabled = amd_pmc_is_enabled,
+ .pmc_idx_to_pmc = amd_pmc_idx_to_pmc,
+ .msr_idx_to_pmc = amd_msr_idx_to_pmc,
+ .is_valid_msr_idx = amd_is_valid_msr_idx,
+ .is_valid_msr = amd_is_valid_msr,
+ .get_msr = amd_pmu_get_msr,
+ .set_msr = amd_pmu_set_msr,
+ .refresh = amd_pmu_refresh,
+ .init = amd_pmu_init,
+ .reset = amd_pmu_reset,
+};