1 // SPDX-License-Identifier: GPL-2.0-only
3 * KVM PMU support for Intel CPUs
5 * Copyright 2011 Red Hat, Inc. and/or its affiliates.
8 * Avi Kivity <avi@redhat.com>
9 * Gleb Natapov <gleb@redhat.com>
11 #include <linux/types.h>
12 #include <linux/kvm_host.h>
13 #include <linux/perf_event.h>
14 #include <asm/perf_event.h>
21 #define MSR_PMC_FULL_WIDTH_BIT (MSR_IA32_PMC0 - MSR_IA32_PERFCTR0)
23 static struct kvm_event_hw_type_mapping intel_arch_events[] = {
24 /* Index must match CPUID 0x0A.EBX bit vector */
25 [0] = { 0x3c, 0x00, PERF_COUNT_HW_CPU_CYCLES },
26 [1] = { 0xc0, 0x00, PERF_COUNT_HW_INSTRUCTIONS },
27 [2] = { 0x3c, 0x01, PERF_COUNT_HW_BUS_CYCLES },
28 [3] = { 0x2e, 0x4f, PERF_COUNT_HW_CACHE_REFERENCES },
29 [4] = { 0x2e, 0x41, PERF_COUNT_HW_CACHE_MISSES },
30 [5] = { 0xc4, 0x00, PERF_COUNT_HW_BRANCH_INSTRUCTIONS },
31 [6] = { 0xc5, 0x00, PERF_COUNT_HW_BRANCH_MISSES },
32 [7] = { 0x00, 0x30, PERF_COUNT_HW_REF_CPU_CYCLES },
35 /* mapping between fixed pmc index and intel_arch_events array */
36 static int fixed_pmc_events[] = {1, 0, 7};
38 static void reprogram_fixed_counters(struct kvm_pmu *pmu, u64 data)
42 for (i = 0; i < pmu->nr_arch_fixed_counters; i++) {
43 u8 new_ctrl = fixed_ctrl_field(data, i);
44 u8 old_ctrl = fixed_ctrl_field(pmu->fixed_ctr_ctrl, i);
47 pmc = get_fixed_pmc(pmu, MSR_CORE_PERF_FIXED_CTR0 + i);
49 if (old_ctrl == new_ctrl)
52 __set_bit(INTEL_PMC_IDX_FIXED + i, pmu->pmc_in_use);
53 reprogram_fixed_counter(pmc, new_ctrl, i);
56 pmu->fixed_ctr_ctrl = data;
59 /* function is called when global control register has been updated. */
60 static void global_ctrl_changed(struct kvm_pmu *pmu, u64 data)
63 u64 diff = pmu->global_ctrl ^ data;
65 pmu->global_ctrl = data;
67 for_each_set_bit(bit, (unsigned long *)&diff, X86_PMC_IDX_MAX)
68 reprogram_counter(pmu, bit);
71 static unsigned intel_find_arch_event(struct kvm_pmu *pmu,
77 for (i = 0; i < ARRAY_SIZE(intel_arch_events); i++)
78 if (intel_arch_events[i].eventsel == event_select
79 && intel_arch_events[i].unit_mask == unit_mask
80 && (pmu->available_event_types & (1 << i)))
83 if (i == ARRAY_SIZE(intel_arch_events))
84 return PERF_COUNT_HW_MAX;
86 return intel_arch_events[i].event_type;
89 static unsigned intel_find_fixed_event(int idx)
92 size_t size = ARRAY_SIZE(fixed_pmc_events);
95 return PERF_COUNT_HW_MAX;
97 event = fixed_pmc_events[array_index_nospec(idx, size)];
98 return intel_arch_events[event].event_type;
101 /* check if a PMC is enabled by comparing it with globl_ctrl bits. */
102 static bool intel_pmc_is_enabled(struct kvm_pmc *pmc)
104 struct kvm_pmu *pmu = pmc_to_pmu(pmc);
106 return test_bit(pmc->idx, (unsigned long *)&pmu->global_ctrl);
109 static struct kvm_pmc *intel_pmc_idx_to_pmc(struct kvm_pmu *pmu, int pmc_idx)
111 if (pmc_idx < INTEL_PMC_IDX_FIXED)
112 return get_gp_pmc(pmu, MSR_P6_EVNTSEL0 + pmc_idx,
115 u32 idx = pmc_idx - INTEL_PMC_IDX_FIXED;
117 return get_fixed_pmc(pmu, idx + MSR_CORE_PERF_FIXED_CTR0);
121 /* returns 0 if idx's corresponding MSR exists; otherwise returns 1. */
122 static int intel_is_valid_rdpmc_ecx(struct kvm_vcpu *vcpu, unsigned int idx)
124 struct kvm_pmu *pmu = vcpu_to_pmu(vcpu);
125 bool fixed = idx & (1u << 30);
129 return (!fixed && idx >= pmu->nr_arch_gp_counters) ||
130 (fixed && idx >= pmu->nr_arch_fixed_counters);
133 static struct kvm_pmc *intel_rdpmc_ecx_to_pmc(struct kvm_vcpu *vcpu,
134 unsigned int idx, u64 *mask)
136 struct kvm_pmu *pmu = vcpu_to_pmu(vcpu);
137 bool fixed = idx & (1u << 30);
138 struct kvm_pmc *counters;
139 unsigned int num_counters;
143 counters = pmu->fixed_counters;
144 num_counters = pmu->nr_arch_fixed_counters;
146 counters = pmu->gp_counters;
147 num_counters = pmu->nr_arch_gp_counters;
149 if (idx >= num_counters)
151 *mask &= pmu->counter_bitmask[fixed ? KVM_PMC_FIXED : KVM_PMC_GP];
152 return &counters[array_index_nospec(idx, num_counters)];
155 static inline bool fw_writes_is_enabled(struct kvm_vcpu *vcpu)
157 if (!guest_cpuid_has(vcpu, X86_FEATURE_PDCM))
160 return vcpu->arch.perf_capabilities & PMU_CAP_FW_WRITES;
163 static inline struct kvm_pmc *get_fw_gp_pmc(struct kvm_pmu *pmu, u32 msr)
165 if (!fw_writes_is_enabled(pmu_to_vcpu(pmu)))
168 return get_gp_pmc(pmu, msr, MSR_IA32_PMC0);
171 static bool intel_is_valid_msr(struct kvm_vcpu *vcpu, u32 msr)
173 struct kvm_pmu *pmu = vcpu_to_pmu(vcpu);
177 case MSR_CORE_PERF_FIXED_CTR_CTRL:
178 case MSR_CORE_PERF_GLOBAL_STATUS:
179 case MSR_CORE_PERF_GLOBAL_CTRL:
180 case MSR_CORE_PERF_GLOBAL_OVF_CTRL:
181 ret = pmu->version > 1;
184 ret = get_gp_pmc(pmu, msr, MSR_IA32_PERFCTR0) ||
185 get_gp_pmc(pmu, msr, MSR_P6_EVNTSEL0) ||
186 get_fixed_pmc(pmu, msr) || get_fw_gp_pmc(pmu, msr);
193 static struct kvm_pmc *intel_msr_idx_to_pmc(struct kvm_vcpu *vcpu, u32 msr)
195 struct kvm_pmu *pmu = vcpu_to_pmu(vcpu);
198 pmc = get_fixed_pmc(pmu, msr);
199 pmc = pmc ? pmc : get_gp_pmc(pmu, msr, MSR_P6_EVNTSEL0);
200 pmc = pmc ? pmc : get_gp_pmc(pmu, msr, MSR_IA32_PERFCTR0);
205 static int intel_pmu_get_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
207 struct kvm_pmu *pmu = vcpu_to_pmu(vcpu);
209 u32 msr = msr_info->index;
212 case MSR_CORE_PERF_FIXED_CTR_CTRL:
213 msr_info->data = pmu->fixed_ctr_ctrl;
215 case MSR_CORE_PERF_GLOBAL_STATUS:
216 msr_info->data = pmu->global_status;
218 case MSR_CORE_PERF_GLOBAL_CTRL:
219 msr_info->data = pmu->global_ctrl;
221 case MSR_CORE_PERF_GLOBAL_OVF_CTRL:
222 msr_info->data = pmu->global_ovf_ctrl;
225 if ((pmc = get_gp_pmc(pmu, msr, MSR_IA32_PERFCTR0)) ||
226 (pmc = get_gp_pmc(pmu, msr, MSR_IA32_PMC0))) {
227 u64 val = pmc_read_counter(pmc);
229 val & pmu->counter_bitmask[KVM_PMC_GP];
231 } else if ((pmc = get_fixed_pmc(pmu, msr))) {
232 u64 val = pmc_read_counter(pmc);
234 val & pmu->counter_bitmask[KVM_PMC_FIXED];
236 } else if ((pmc = get_gp_pmc(pmu, msr, MSR_P6_EVNTSEL0))) {
237 msr_info->data = pmc->eventsel;
245 static int intel_pmu_set_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
247 struct kvm_pmu *pmu = vcpu_to_pmu(vcpu);
249 u32 msr = msr_info->index;
250 u64 data = msr_info->data;
253 case MSR_CORE_PERF_FIXED_CTR_CTRL:
254 if (pmu->fixed_ctr_ctrl == data)
256 if (!(data & 0xfffffffffffff444ull)) {
257 reprogram_fixed_counters(pmu, data);
261 case MSR_CORE_PERF_GLOBAL_STATUS:
262 if (msr_info->host_initiated) {
263 pmu->global_status = data;
267 case MSR_CORE_PERF_GLOBAL_CTRL:
268 if (pmu->global_ctrl == data)
270 if (kvm_valid_perf_global_ctrl(pmu, data)) {
271 global_ctrl_changed(pmu, data);
275 case MSR_CORE_PERF_GLOBAL_OVF_CTRL:
276 if (!(data & pmu->global_ovf_ctrl_mask)) {
277 if (!msr_info->host_initiated)
278 pmu->global_status &= ~data;
279 pmu->global_ovf_ctrl = data;
284 if ((pmc = get_gp_pmc(pmu, msr, MSR_IA32_PERFCTR0)) ||
285 (pmc = get_gp_pmc(pmu, msr, MSR_IA32_PMC0))) {
286 if ((msr & MSR_PMC_FULL_WIDTH_BIT) &&
287 (data & ~pmu->counter_bitmask[KVM_PMC_GP]))
289 if (!msr_info->host_initiated &&
290 !(msr & MSR_PMC_FULL_WIDTH_BIT))
291 data = (s64)(s32)data;
292 pmc->counter += data - pmc_read_counter(pmc);
294 perf_event_period(pmc->perf_event,
295 get_sample_period(pmc, data));
297 } else if ((pmc = get_fixed_pmc(pmu, msr))) {
298 pmc->counter += data - pmc_read_counter(pmc);
300 perf_event_period(pmc->perf_event,
301 get_sample_period(pmc, data));
303 } else if ((pmc = get_gp_pmc(pmu, msr, MSR_P6_EVNTSEL0))) {
304 if (data == pmc->eventsel)
306 if (!(data & pmu->reserved_bits)) {
307 reprogram_gp_counter(pmc, data);
316 static void intel_pmu_refresh(struct kvm_vcpu *vcpu)
318 struct kvm_pmu *pmu = vcpu_to_pmu(vcpu);
319 struct x86_pmu_capability x86_pmu;
320 struct kvm_cpuid_entry2 *entry;
321 union cpuid10_eax eax;
322 union cpuid10_edx edx;
324 pmu->nr_arch_gp_counters = 0;
325 pmu->nr_arch_fixed_counters = 0;
326 pmu->counter_bitmask[KVM_PMC_GP] = 0;
327 pmu->counter_bitmask[KVM_PMC_FIXED] = 0;
329 pmu->reserved_bits = 0xffffffff00200000ull;
330 vcpu->arch.perf_capabilities = 0;
332 entry = kvm_find_cpuid_entry(vcpu, 0xa, 0);
335 eax.full = entry->eax;
336 edx.full = entry->edx;
338 pmu->version = eax.split.version_id;
342 perf_get_x86_pmu_capability(&x86_pmu);
343 if (guest_cpuid_has(vcpu, X86_FEATURE_PDCM))
344 vcpu->arch.perf_capabilities = vmx_get_perf_capabilities();
346 pmu->nr_arch_gp_counters = min_t(int, eax.split.num_counters,
347 x86_pmu.num_counters_gp);
348 pmu->counter_bitmask[KVM_PMC_GP] = ((u64)1 << eax.split.bit_width) - 1;
349 pmu->available_event_types = ~entry->ebx &
350 ((1ull << eax.split.mask_length) - 1);
352 if (pmu->version == 1) {
353 pmu->nr_arch_fixed_counters = 0;
355 pmu->nr_arch_fixed_counters =
356 min_t(int, edx.split.num_counters_fixed,
357 x86_pmu.num_counters_fixed);
358 pmu->counter_bitmask[KVM_PMC_FIXED] =
359 ((u64)1 << edx.split.bit_width_fixed) - 1;
362 pmu->global_ctrl = ((1ull << pmu->nr_arch_gp_counters) - 1) |
363 (((1ull << pmu->nr_arch_fixed_counters) - 1) << INTEL_PMC_IDX_FIXED);
364 pmu->global_ctrl_mask = ~pmu->global_ctrl;
365 pmu->global_ovf_ctrl_mask = pmu->global_ctrl_mask
366 & ~(MSR_CORE_PERF_GLOBAL_OVF_CTRL_OVF_BUF |
367 MSR_CORE_PERF_GLOBAL_OVF_CTRL_COND_CHGD);
368 if (vmx_pt_mode_is_host_guest())
369 pmu->global_ovf_ctrl_mask &=
370 ~MSR_CORE_PERF_GLOBAL_OVF_CTRL_TRACE_TOPA_PMI;
372 entry = kvm_find_cpuid_entry(vcpu, 7, 0);
374 (boot_cpu_has(X86_FEATURE_HLE) || boot_cpu_has(X86_FEATURE_RTM)) &&
375 (entry->ebx & (X86_FEATURE_HLE|X86_FEATURE_RTM)))
376 pmu->reserved_bits ^= HSW_IN_TX|HSW_IN_TX_CHECKPOINTED;
378 bitmap_set(pmu->all_valid_pmc_idx,
379 0, pmu->nr_arch_gp_counters);
380 bitmap_set(pmu->all_valid_pmc_idx,
381 INTEL_PMC_MAX_GENERIC, pmu->nr_arch_fixed_counters);
383 nested_vmx_pmu_entry_exit_ctls_update(vcpu);
386 static void intel_pmu_init(struct kvm_vcpu *vcpu)
389 struct kvm_pmu *pmu = vcpu_to_pmu(vcpu);
391 for (i = 0; i < INTEL_PMC_MAX_GENERIC; i++) {
392 pmu->gp_counters[i].type = KVM_PMC_GP;
393 pmu->gp_counters[i].vcpu = vcpu;
394 pmu->gp_counters[i].idx = i;
395 pmu->gp_counters[i].current_config = 0;
398 for (i = 0; i < INTEL_PMC_MAX_FIXED; i++) {
399 pmu->fixed_counters[i].type = KVM_PMC_FIXED;
400 pmu->fixed_counters[i].vcpu = vcpu;
401 pmu->fixed_counters[i].idx = i + INTEL_PMC_IDX_FIXED;
402 pmu->fixed_counters[i].current_config = 0;
406 static void intel_pmu_reset(struct kvm_vcpu *vcpu)
408 struct kvm_pmu *pmu = vcpu_to_pmu(vcpu);
409 struct kvm_pmc *pmc = NULL;
412 for (i = 0; i < INTEL_PMC_MAX_GENERIC; i++) {
413 pmc = &pmu->gp_counters[i];
415 pmc_stop_counter(pmc);
416 pmc->counter = pmc->eventsel = 0;
419 for (i = 0; i < INTEL_PMC_MAX_FIXED; i++) {
420 pmc = &pmu->fixed_counters[i];
422 pmc_stop_counter(pmc);
426 pmu->fixed_ctr_ctrl = pmu->global_ctrl = pmu->global_status =
427 pmu->global_ovf_ctrl = 0;
430 struct kvm_pmu_ops intel_pmu_ops = {
431 .find_arch_event = intel_find_arch_event,
432 .find_fixed_event = intel_find_fixed_event,
433 .pmc_is_enabled = intel_pmc_is_enabled,
434 .pmc_idx_to_pmc = intel_pmc_idx_to_pmc,
435 .rdpmc_ecx_to_pmc = intel_rdpmc_ecx_to_pmc,
436 .msr_idx_to_pmc = intel_msr_idx_to_pmc,
437 .is_valid_rdpmc_ecx = intel_is_valid_rdpmc_ecx,
438 .is_valid_msr = intel_is_valid_msr,
439 .get_msr = intel_pmu_get_msr,
440 .set_msr = intel_pmu_set_msr,
441 .refresh = intel_pmu_refresh,
442 .init = intel_pmu_init,
443 .reset = intel_pmu_reset,