1 // SPDX-License-Identifier: GPL-2.0 2 #include <linux/perf_event.h> 3 #include <asm/intel-family.h> 4 5 enum perf_msr_id { 6 PERF_MSR_TSC = 0, 7 PERF_MSR_APERF = 1, 8 PERF_MSR_MPERF = 2, 9 PERF_MSR_PPERF = 3, 10 PERF_MSR_SMI = 4, 11 PERF_MSR_PTSC = 5, 12 PERF_MSR_IRPERF = 6, 13 PERF_MSR_THERM = 7, 14 PERF_MSR_THERM_SNAP = 8, 15 PERF_MSR_THERM_UNIT = 9, 16 PERF_MSR_EVENT_MAX, 17 }; 18 19 static bool test_aperfmperf(int idx) 20 { 21 return boot_cpu_has(X86_FEATURE_APERFMPERF); 22 } 23 24 static bool test_ptsc(int idx) 25 { 26 return boot_cpu_has(X86_FEATURE_PTSC); 27 } 28 29 static bool test_irperf(int idx) 30 { 31 return boot_cpu_has(X86_FEATURE_IRPERF); 32 } 33 34 static bool test_therm_status(int idx) 35 { 36 return boot_cpu_has(X86_FEATURE_DTHERM); 37 } 38 39 static bool test_intel(int idx) 40 { 41 if (boot_cpu_data.x86_vendor != X86_VENDOR_INTEL || 42 boot_cpu_data.x86 != 6) 43 return false; 44 45 switch (boot_cpu_data.x86_model) { 46 case INTEL_FAM6_NEHALEM: 47 case INTEL_FAM6_NEHALEM_G: 48 case INTEL_FAM6_NEHALEM_EP: 49 case INTEL_FAM6_NEHALEM_EX: 50 51 case INTEL_FAM6_WESTMERE: 52 case INTEL_FAM6_WESTMERE_EP: 53 case INTEL_FAM6_WESTMERE_EX: 54 55 case INTEL_FAM6_SANDYBRIDGE: 56 case INTEL_FAM6_SANDYBRIDGE_X: 57 58 case INTEL_FAM6_IVYBRIDGE: 59 case INTEL_FAM6_IVYBRIDGE_X: 60 61 case INTEL_FAM6_HASWELL_CORE: 62 case INTEL_FAM6_HASWELL_X: 63 case INTEL_FAM6_HASWELL_ULT: 64 case INTEL_FAM6_HASWELL_GT3E: 65 66 case INTEL_FAM6_BROADWELL_CORE: 67 case INTEL_FAM6_BROADWELL_XEON_D: 68 case INTEL_FAM6_BROADWELL_GT3E: 69 case INTEL_FAM6_BROADWELL_X: 70 71 case INTEL_FAM6_ATOM_SILVERMONT1: 72 case INTEL_FAM6_ATOM_SILVERMONT2: 73 case INTEL_FAM6_ATOM_AIRMONT: 74 75 case INTEL_FAM6_ATOM_GOLDMONT: 76 case INTEL_FAM6_ATOM_DENVERTON: 77 78 case INTEL_FAM6_ATOM_GEMINI_LAKE: 79 80 case INTEL_FAM6_XEON_PHI_KNL: 81 case INTEL_FAM6_XEON_PHI_KNM: 82 if (idx == PERF_MSR_SMI) 83 return true; 84 break; 85 86 case INTEL_FAM6_SKYLAKE_MOBILE: 87 case INTEL_FAM6_SKYLAKE_DESKTOP: 88 case INTEL_FAM6_SKYLAKE_X: 89 case INTEL_FAM6_KABYLAKE_MOBILE: 90 case INTEL_FAM6_KABYLAKE_DESKTOP: 91 if (idx == PERF_MSR_SMI || idx == PERF_MSR_PPERF) 92 return true; 93 break; 94 } 95 96 return false; 97 } 98 99 struct perf_msr { 100 u64 msr; 101 struct perf_pmu_events_attr *attr; 102 bool (*test)(int idx); 103 }; 104 105 PMU_EVENT_ATTR_STRING(tsc, evattr_tsc, "event=0x00" ); 106 PMU_EVENT_ATTR_STRING(aperf, evattr_aperf, "event=0x01" ); 107 PMU_EVENT_ATTR_STRING(mperf, evattr_mperf, "event=0x02" ); 108 PMU_EVENT_ATTR_STRING(pperf, evattr_pperf, "event=0x03" ); 109 PMU_EVENT_ATTR_STRING(smi, evattr_smi, "event=0x04" ); 110 PMU_EVENT_ATTR_STRING(ptsc, evattr_ptsc, "event=0x05" ); 111 PMU_EVENT_ATTR_STRING(irperf, evattr_irperf, "event=0x06" ); 112 PMU_EVENT_ATTR_STRING(cpu_thermal_margin, evattr_therm, "event=0x07" ); 113 PMU_EVENT_ATTR_STRING(cpu_thermal_margin.snapshot, evattr_therm_snap, "1" ); 114 PMU_EVENT_ATTR_STRING(cpu_thermal_margin.unit, evattr_therm_unit, "C" ); 115 116 static struct perf_msr msr[] = { 117 [PERF_MSR_TSC] = { 0, &evattr_tsc, NULL, }, 118 [PERF_MSR_APERF] = { MSR_IA32_APERF, &evattr_aperf, test_aperfmperf, }, 119 [PERF_MSR_MPERF] = { MSR_IA32_MPERF, &evattr_mperf, test_aperfmperf, }, 120 [PERF_MSR_PPERF] = { MSR_PPERF, &evattr_pperf, test_intel, }, 121 [PERF_MSR_SMI] = { MSR_SMI_COUNT, &evattr_smi, test_intel, }, 122 [PERF_MSR_PTSC] = { MSR_F15H_PTSC, &evattr_ptsc, test_ptsc, }, 123 [PERF_MSR_IRPERF] = { MSR_F17H_IRPERF, &evattr_irperf, test_irperf, }, 124 [PERF_MSR_THERM] = { MSR_IA32_THERM_STATUS, &evattr_therm, test_therm_status, }, 125 [PERF_MSR_THERM_SNAP] = { MSR_IA32_THERM_STATUS, &evattr_therm_snap, test_therm_status, }, 126 [PERF_MSR_THERM_UNIT] = { MSR_IA32_THERM_STATUS, &evattr_therm_unit, test_therm_status, }, 127 }; 128 129 static struct attribute *events_attrs[PERF_MSR_EVENT_MAX + 1] = { 130 NULL, 131 }; 132 133 static struct attribute_group events_attr_group = { 134 .name = "events", 135 .attrs = events_attrs, 136 }; 137 138 PMU_FORMAT_ATTR(event, "config:0-63"); 139 static struct attribute *format_attrs[] = { 140 &format_attr_event.attr, 141 NULL, 142 }; 143 static struct attribute_group format_attr_group = { 144 .name = "format", 145 .attrs = format_attrs, 146 }; 147 148 static const struct attribute_group *attr_groups[] = { 149 &events_attr_group, 150 &format_attr_group, 151 NULL, 152 }; 153 154 static int msr_event_init(struct perf_event *event) 155 { 156 u64 cfg = event->attr.config; 157 158 if (event->attr.type != event->pmu->type) 159 return -ENOENT; 160 161 if (cfg >= PERF_MSR_EVENT_MAX) 162 return -EINVAL; 163 164 /* unsupported modes and filters */ 165 if (event->attr.exclude_user || 166 event->attr.exclude_kernel || 167 event->attr.exclude_hv || 168 event->attr.exclude_idle || 169 event->attr.exclude_host || 170 event->attr.exclude_guest || 171 event->attr.sample_period) /* no sampling */ 172 return -EINVAL; 173 174 if (!msr[cfg].attr) 175 return -EINVAL; 176 177 event->hw.idx = -1; 178 event->hw.event_base = msr[cfg].msr; 179 event->hw.config = cfg; 180 181 return 0; 182 } 183 184 static inline u64 msr_read_counter(struct perf_event *event) 185 { 186 u64 now; 187 188 if (event->hw.event_base) 189 rdmsrl(event->hw.event_base, now); 190 else 191 now = rdtsc_ordered(); 192 193 return now; 194 } 195 196 static void msr_event_update(struct perf_event *event) 197 { 198 u64 prev, now; 199 s64 delta; 200 201 /* Careful, an NMI might modify the previous event value: */ 202 again: 203 prev = local64_read(&event->hw.prev_count); 204 now = msr_read_counter(event); 205 206 if (local64_cmpxchg(&event->hw.prev_count, prev, now) != prev) 207 goto again; 208 209 delta = now - prev; 210 if (unlikely(event->hw.event_base == MSR_SMI_COUNT)) { 211 delta = sign_extend64(delta, 31); 212 local64_add(delta, &event->count); 213 } else if (unlikely(event->hw.event_base == MSR_IA32_THERM_STATUS)) { 214 /* If valid, extract digital readout, otherwise set to -1: */ 215 now = now & (1ULL << 31) ? (now >> 16) & 0x3f : -1; 216 local64_set(&event->count, now); 217 } else { 218 local64_add(delta, &event->count); 219 } 220 } 221 222 static void msr_event_start(struct perf_event *event, int flags) 223 { 224 u64 now = msr_read_counter(event); 225 226 local64_set(&event->hw.prev_count, now); 227 } 228 229 static void msr_event_stop(struct perf_event *event, int flags) 230 { 231 msr_event_update(event); 232 } 233 234 static void msr_event_del(struct perf_event *event, int flags) 235 { 236 msr_event_stop(event, PERF_EF_UPDATE); 237 } 238 239 static int msr_event_add(struct perf_event *event, int flags) 240 { 241 if (flags & PERF_EF_START) 242 msr_event_start(event, flags); 243 244 return 0; 245 } 246 247 static struct pmu pmu_msr = { 248 .task_ctx_nr = perf_sw_context, 249 .attr_groups = attr_groups, 250 .event_init = msr_event_init, 251 .add = msr_event_add, 252 .del = msr_event_del, 253 .start = msr_event_start, 254 .stop = msr_event_stop, 255 .read = msr_event_update, 256 .capabilities = PERF_PMU_CAP_NO_INTERRUPT, 257 }; 258 259 static int __init msr_init(void) 260 { 261 int i, j = 0; 262 263 if (!boot_cpu_has(X86_FEATURE_TSC)) { 264 pr_cont("no MSR PMU driver.\n"); 265 return 0; 266 } 267 268 /* Probe the MSRs. */ 269 for (i = PERF_MSR_TSC + 1; i < PERF_MSR_EVENT_MAX; i++) { 270 u64 val; 271 272 /* Virt sucks; you cannot tell if a R/O MSR is present :/ */ 273 if (!msr[i].test(i) || rdmsrl_safe(msr[i].msr, &val)) 274 msr[i].attr = NULL; 275 } 276 277 /* List remaining MSRs in the sysfs attrs. */ 278 for (i = 0; i < PERF_MSR_EVENT_MAX; i++) { 279 if (msr[i].attr) 280 events_attrs[j++] = &msr[i].attr->attr.attr; 281 } 282 events_attrs[j] = NULL; 283 284 perf_pmu_register(&pmu_msr, "msr", -1); 285 286 return 0; 287 } 288 device_initcall(msr_init); 289