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