1 /* SPDX-License-Identifier: GPL-2.0 */ 2 #ifndef __KVM_X86_PMU_H 3 #define __KVM_X86_PMU_H 4 5 #include <linux/nospec.h> 6 7 #include <asm/kvm_host.h> 8 9 #define vcpu_to_pmu(vcpu) (&(vcpu)->arch.pmu) 10 #define pmu_to_vcpu(pmu) (container_of((pmu), struct kvm_vcpu, arch.pmu)) 11 #define pmc_to_pmu(pmc) (&(pmc)->vcpu->arch.pmu) 12 13 #define MSR_IA32_MISC_ENABLE_PMU_RO_MASK (MSR_IA32_MISC_ENABLE_PEBS_UNAVAIL | \ 14 MSR_IA32_MISC_ENABLE_BTS_UNAVAIL) 15 16 /* retrieve the 4 bits for EN and PMI out of IA32_FIXED_CTR_CTRL */ 17 #define fixed_ctrl_field(ctrl_reg, idx) \ 18 (((ctrl_reg) >> ((idx) * INTEL_FIXED_BITS_STRIDE)) & INTEL_FIXED_BITS_MASK) 19 20 #define VMWARE_BACKDOOR_PMC_HOST_TSC 0x10000 21 #define VMWARE_BACKDOOR_PMC_REAL_TIME 0x10001 22 #define VMWARE_BACKDOOR_PMC_APPARENT_TIME 0x10002 23 24 #define KVM_FIXED_PMC_BASE_IDX INTEL_PMC_IDX_FIXED 25 26 struct kvm_pmu_emulated_event_selectors { 27 u64 INSTRUCTIONS_RETIRED; 28 u64 BRANCH_INSTRUCTIONS_RETIRED; 29 }; 30 31 struct kvm_pmu_ops { 32 struct kvm_pmc *(*rdpmc_ecx_to_pmc)(struct kvm_vcpu *vcpu, 33 unsigned int idx, u64 *mask); 34 struct kvm_pmc *(*msr_idx_to_pmc)(struct kvm_vcpu *vcpu, u32 msr); 35 int (*check_rdpmc_early)(struct kvm_vcpu *vcpu, unsigned int idx); 36 bool (*is_valid_msr)(struct kvm_vcpu *vcpu, u32 msr); 37 int (*get_msr)(struct kvm_vcpu *vcpu, struct msr_data *msr_info); 38 int (*set_msr)(struct kvm_vcpu *vcpu, struct msr_data *msr_info); 39 void (*refresh)(struct kvm_vcpu *vcpu); 40 void (*init)(struct kvm_vcpu *vcpu); 41 void (*reset)(struct kvm_vcpu *vcpu); 42 void (*deliver_pmi)(struct kvm_vcpu *vcpu); 43 void (*cleanup)(struct kvm_vcpu *vcpu); 44 45 const u64 EVENTSEL_EVENT; 46 const int MAX_NR_GP_COUNTERS; 47 const int MIN_NR_GP_COUNTERS; 48 }; 49 50 void kvm_pmu_ops_update(const struct kvm_pmu_ops *pmu_ops); 51 kvm_pmu_has_perf_global_ctrl(struct kvm_pmu * pmu)52 static inline bool kvm_pmu_has_perf_global_ctrl(struct kvm_pmu *pmu) 53 { 54 /* 55 * Architecturally, Intel's SDM states that IA32_PERF_GLOBAL_CTRL is 56 * supported if "CPUID.0AH: EAX[7:0] > 0", i.e. if the PMU version is 57 * greater than zero. However, KVM only exposes and emulates the MSR 58 * to/for the guest if the guest PMU supports at least "Architectural 59 * Performance Monitoring Version 2". 60 * 61 * AMD's version of PERF_GLOBAL_CTRL conveniently shows up with v2. 62 */ 63 return pmu->version > 1; 64 } 65 66 /* 67 * KVM tracks all counters in 64-bit bitmaps, with general purpose counters 68 * mapped to bits 31:0 and fixed counters mapped to 63:32, e.g. fixed counter 0 69 * is tracked internally via index 32. On Intel, (AMD doesn't support fixed 70 * counters), this mirrors how fixed counters are mapped to PERF_GLOBAL_CTRL 71 * and similar MSRs, i.e. tracking fixed counters at base index 32 reduces the 72 * amounter of boilerplate needed to iterate over PMCs *and* simplifies common 73 * enabling/disable/reset operations. 74 * 75 * WARNING! This helper is only for lookups that are initiated by KVM, it is 76 * NOT safe for guest lookups, e.g. will do the wrong thing if passed a raw 77 * ECX value from RDPMC (fixed counters are accessed by setting bit 30 in ECX 78 * for RDPMC, not by adding 32 to the fixed counter index). 79 */ kvm_pmc_idx_to_pmc(struct kvm_pmu * pmu,int idx)80 static inline struct kvm_pmc *kvm_pmc_idx_to_pmc(struct kvm_pmu *pmu, int idx) 81 { 82 if (idx < pmu->nr_arch_gp_counters) 83 return &pmu->gp_counters[idx]; 84 85 idx -= KVM_FIXED_PMC_BASE_IDX; 86 if (idx >= 0 && idx < pmu->nr_arch_fixed_counters) 87 return &pmu->fixed_counters[idx]; 88 89 return NULL; 90 } 91 92 #define kvm_for_each_pmc(pmu, pmc, i, bitmap) \ 93 for_each_set_bit(i, bitmap, X86_PMC_IDX_MAX) \ 94 if (!(pmc = kvm_pmc_idx_to_pmc(pmu, i))) \ 95 continue; \ 96 else \ 97 pmc_bitmask(struct kvm_pmc * pmc)98 static inline u64 pmc_bitmask(struct kvm_pmc *pmc) 99 { 100 struct kvm_pmu *pmu = pmc_to_pmu(pmc); 101 102 return pmu->counter_bitmask[pmc->type]; 103 } 104 pmc_read_counter(struct kvm_pmc * pmc)105 static inline u64 pmc_read_counter(struct kvm_pmc *pmc) 106 { 107 u64 counter, enabled, running; 108 109 counter = pmc->counter + pmc->emulated_counter; 110 111 if (pmc->perf_event && !pmc->is_paused) 112 counter += perf_event_read_value(pmc->perf_event, 113 &enabled, &running); 114 /* FIXME: Scaling needed? */ 115 return counter & pmc_bitmask(pmc); 116 } 117 118 void pmc_write_counter(struct kvm_pmc *pmc, u64 val); 119 pmc_is_gp(struct kvm_pmc * pmc)120 static inline bool pmc_is_gp(struct kvm_pmc *pmc) 121 { 122 return pmc->type == KVM_PMC_GP; 123 } 124 pmc_is_fixed(struct kvm_pmc * pmc)125 static inline bool pmc_is_fixed(struct kvm_pmc *pmc) 126 { 127 return pmc->type == KVM_PMC_FIXED; 128 } 129 kvm_valid_perf_global_ctrl(struct kvm_pmu * pmu,u64 data)130 static inline bool kvm_valid_perf_global_ctrl(struct kvm_pmu *pmu, 131 u64 data) 132 { 133 return !(pmu->global_ctrl_rsvd & data); 134 } 135 136 /* returns general purpose PMC with the specified MSR. Note that it can be 137 * used for both PERFCTRn and EVNTSELn; that is why it accepts base as a 138 * parameter to tell them apart. 139 */ get_gp_pmc(struct kvm_pmu * pmu,u32 msr,u32 base)140 static inline struct kvm_pmc *get_gp_pmc(struct kvm_pmu *pmu, u32 msr, 141 u32 base) 142 { 143 if (msr >= base && msr < base + pmu->nr_arch_gp_counters) { 144 u32 index = array_index_nospec(msr - base, 145 pmu->nr_arch_gp_counters); 146 147 return &pmu->gp_counters[index]; 148 } 149 150 return NULL; 151 } 152 153 /* returns fixed PMC with the specified MSR */ get_fixed_pmc(struct kvm_pmu * pmu,u32 msr)154 static inline struct kvm_pmc *get_fixed_pmc(struct kvm_pmu *pmu, u32 msr) 155 { 156 int base = MSR_CORE_PERF_FIXED_CTR0; 157 158 if (msr >= base && msr < base + pmu->nr_arch_fixed_counters) { 159 u32 index = array_index_nospec(msr - base, 160 pmu->nr_arch_fixed_counters); 161 162 return &pmu->fixed_counters[index]; 163 } 164 165 return NULL; 166 } 167 pmc_speculative_in_use(struct kvm_pmc * pmc)168 static inline bool pmc_speculative_in_use(struct kvm_pmc *pmc) 169 { 170 struct kvm_pmu *pmu = pmc_to_pmu(pmc); 171 172 if (pmc_is_fixed(pmc)) 173 return fixed_ctrl_field(pmu->fixed_ctr_ctrl, 174 pmc->idx - KVM_FIXED_PMC_BASE_IDX) & 175 (INTEL_FIXED_0_KERNEL | INTEL_FIXED_0_USER); 176 177 return pmc->eventsel & ARCH_PERFMON_EVENTSEL_ENABLE; 178 } 179 180 extern struct x86_pmu_capability kvm_pmu_cap; 181 extern struct kvm_pmu_emulated_event_selectors kvm_pmu_eventsel; 182 kvm_init_pmu_capability(const struct kvm_pmu_ops * pmu_ops)183 static inline void kvm_init_pmu_capability(const struct kvm_pmu_ops *pmu_ops) 184 { 185 bool is_intel = boot_cpu_data.x86_vendor == X86_VENDOR_INTEL; 186 int min_nr_gp_ctrs = pmu_ops->MIN_NR_GP_COUNTERS; 187 188 /* 189 * Hybrid PMUs don't play nice with virtualization without careful 190 * configuration by userspace, and KVM's APIs for reporting supported 191 * vPMU features do not account for hybrid PMUs. Disable vPMU support 192 * for hybrid PMUs until KVM gains a way to let userspace opt-in. 193 */ 194 if (cpu_feature_enabled(X86_FEATURE_HYBRID_CPU)) 195 enable_pmu = false; 196 197 if (enable_pmu) { 198 perf_get_x86_pmu_capability(&kvm_pmu_cap); 199 200 /* 201 * WARN if perf did NOT disable hardware PMU if the number of 202 * architecturally required GP counters aren't present, i.e. if 203 * there are a non-zero number of counters, but fewer than what 204 * is architecturally required. 205 */ 206 if (!kvm_pmu_cap.num_counters_gp || 207 WARN_ON_ONCE(kvm_pmu_cap.num_counters_gp < min_nr_gp_ctrs)) 208 enable_pmu = false; 209 else if (is_intel && !kvm_pmu_cap.version) 210 enable_pmu = false; 211 } 212 213 if (!enable_pmu) { 214 memset(&kvm_pmu_cap, 0, sizeof(kvm_pmu_cap)); 215 return; 216 } 217 218 kvm_pmu_cap.version = min(kvm_pmu_cap.version, 2); 219 kvm_pmu_cap.num_counters_gp = min(kvm_pmu_cap.num_counters_gp, 220 pmu_ops->MAX_NR_GP_COUNTERS); 221 kvm_pmu_cap.num_counters_fixed = min(kvm_pmu_cap.num_counters_fixed, 222 KVM_MAX_NR_FIXED_COUNTERS); 223 224 kvm_pmu_eventsel.INSTRUCTIONS_RETIRED = 225 perf_get_hw_event_config(PERF_COUNT_HW_INSTRUCTIONS); 226 kvm_pmu_eventsel.BRANCH_INSTRUCTIONS_RETIRED = 227 perf_get_hw_event_config(PERF_COUNT_HW_BRANCH_INSTRUCTIONS); 228 } 229 kvm_pmu_request_counter_reprogram(struct kvm_pmc * pmc)230 static inline void kvm_pmu_request_counter_reprogram(struct kvm_pmc *pmc) 231 { 232 set_bit(pmc->idx, pmc_to_pmu(pmc)->reprogram_pmi); 233 kvm_make_request(KVM_REQ_PMU, pmc->vcpu); 234 } 235 reprogram_counters(struct kvm_pmu * pmu,u64 diff)236 static inline void reprogram_counters(struct kvm_pmu *pmu, u64 diff) 237 { 238 int bit; 239 240 if (!diff) 241 return; 242 243 for_each_set_bit(bit, (unsigned long *)&diff, X86_PMC_IDX_MAX) 244 set_bit(bit, pmu->reprogram_pmi); 245 kvm_make_request(KVM_REQ_PMU, pmu_to_vcpu(pmu)); 246 } 247 248 /* 249 * Check if a PMC is enabled by comparing it against global_ctrl bits. 250 * 251 * If the vPMU doesn't have global_ctrl MSR, all vPMCs are enabled. 252 */ pmc_is_globally_enabled(struct kvm_pmc * pmc)253 static inline bool pmc_is_globally_enabled(struct kvm_pmc *pmc) 254 { 255 struct kvm_pmu *pmu = pmc_to_pmu(pmc); 256 257 if (!kvm_pmu_has_perf_global_ctrl(pmu)) 258 return true; 259 260 return test_bit(pmc->idx, (unsigned long *)&pmu->global_ctrl); 261 } 262 263 void kvm_pmu_deliver_pmi(struct kvm_vcpu *vcpu); 264 void kvm_pmu_handle_event(struct kvm_vcpu *vcpu); 265 int kvm_pmu_rdpmc(struct kvm_vcpu *vcpu, unsigned pmc, u64 *data); 266 int kvm_pmu_check_rdpmc_early(struct kvm_vcpu *vcpu, unsigned int idx); 267 bool kvm_pmu_is_valid_msr(struct kvm_vcpu *vcpu, u32 msr); 268 int kvm_pmu_get_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info); 269 int kvm_pmu_set_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info); 270 void kvm_pmu_refresh(struct kvm_vcpu *vcpu); 271 void kvm_pmu_init(struct kvm_vcpu *vcpu); 272 void kvm_pmu_cleanup(struct kvm_vcpu *vcpu); 273 void kvm_pmu_destroy(struct kvm_vcpu *vcpu); 274 int kvm_vm_ioctl_set_pmu_event_filter(struct kvm *kvm, void __user *argp); 275 void kvm_pmu_trigger_event(struct kvm_vcpu *vcpu, u64 eventsel); 276 277 bool is_vmware_backdoor_pmc(u32 pmc_idx); 278 279 extern struct kvm_pmu_ops intel_pmu_ops; 280 extern struct kvm_pmu_ops amd_pmu_ops; 281 #endif /* __KVM_X86_PMU_H */ 282