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) (((ctrl_reg) >> ((idx)*4)) & 0xf)
18
19#define VMWARE_BACKDOOR_PMC_HOST_TSC 0x10000
20#define VMWARE_BACKDOOR_PMC_REAL_TIME 0x10001
21#define VMWARE_BACKDOOR_PMC_APPARENT_TIME 0x10002
22
23#define KVM_FIXED_PMC_BASE_IDX INTEL_PMC_IDX_FIXED
24
25struct kvm_pmu_emulated_event_selectors {
26 u64 INSTRUCTIONS_RETIRED;
27 u64 BRANCH_INSTRUCTIONS_RETIRED;
28};
29
30struct kvm_pmu_ops {
31 struct kvm_pmc *(*rdpmc_ecx_to_pmc)(struct kvm_vcpu *vcpu,
32 unsigned int idx, u64 *mask);
33 struct kvm_pmc *(*msr_idx_to_pmc)(struct kvm_vcpu *vcpu, u32 msr);
34 int (*check_rdpmc_early)(struct kvm_vcpu *vcpu, unsigned int idx);
35 bool (*is_valid_msr)(struct kvm_vcpu *vcpu, u32 msr);
36 int (*get_msr)(struct kvm_vcpu *vcpu, struct msr_data *msr_info);
37 int (*set_msr)(struct kvm_vcpu *vcpu, struct msr_data *msr_info);
38 void (*refresh)(struct kvm_vcpu *vcpu);
39 void (*init)(struct kvm_vcpu *vcpu);
40 void (*reset)(struct kvm_vcpu *vcpu);
41 void (*deliver_pmi)(struct kvm_vcpu *vcpu);
42 void (*cleanup)(struct kvm_vcpu *vcpu);
43
44 const u64 EVENTSEL_EVENT;
45 const int MAX_NR_GP_COUNTERS;
46 const int MIN_NR_GP_COUNTERS;
47};
48
49void kvm_pmu_ops_update(const struct kvm_pmu_ops *pmu_ops);
50
51static inline bool kvm_pmu_has_perf_global_ctrl(struct kvm_pmu *pmu)
52{
53 /*
54 * Architecturally, Intel's SDM states that IA32_PERF_GLOBAL_CTRL is
55 * supported if "CPUID.0AH: EAX[7:0] > 0", i.e. if the PMU version is
56 * greater than zero. However, KVM only exposes and emulates the MSR
57 * to/for the guest if the guest PMU supports at least "Architectural
58 * Performance Monitoring Version 2".
59 *
60 * AMD's version of PERF_GLOBAL_CTRL conveniently shows up with v2.
61 */
62 return pmu->version > 1;
63}
64
65/*
66 * KVM tracks all counters in 64-bit bitmaps, with general purpose counters
67 * mapped to bits 31:0 and fixed counters mapped to 63:32, e.g. fixed counter 0
68 * is tracked internally via index 32. On Intel, (AMD doesn't support fixed
69 * counters), this mirrors how fixed counters are mapped to PERF_GLOBAL_CTRL
70 * and similar MSRs, i.e. tracking fixed counters at base index 32 reduces the
71 * amounter of boilerplate needed to iterate over PMCs *and* simplifies common
72 * enabling/disable/reset operations.
73 *
74 * WARNING! This helper is only for lookups that are initiated by KVM, it is
75 * NOT safe for guest lookups, e.g. will do the wrong thing if passed a raw
76 * ECX value from RDPMC (fixed counters are accessed by setting bit 30 in ECX
77 * for RDPMC, not by adding 32 to the fixed counter index).
78 */
79static inline struct kvm_pmc *kvm_pmc_idx_to_pmc(struct kvm_pmu *pmu, int idx)
80{
81 if (idx < pmu->nr_arch_gp_counters)
82 return &pmu->gp_counters[idx];
83
84 idx -= KVM_FIXED_PMC_BASE_IDX;
85 if (idx >= 0 && idx < pmu->nr_arch_fixed_counters)
86 return &pmu->fixed_counters[idx];
87
88 return NULL;
89}
90
91#define kvm_for_each_pmc(pmu, pmc, i, bitmap) \
92 for_each_set_bit(i, bitmap, X86_PMC_IDX_MAX) \
93 if (!(pmc = kvm_pmc_idx_to_pmc(pmu, i))) \
94 continue; \
95 else \
96
97static inline u64 pmc_bitmask(struct kvm_pmc *pmc)
98{
99 struct kvm_pmu *pmu = pmc_to_pmu(pmc);
100
101 return pmu->counter_bitmask[pmc->type];
102}
103
104static inline u64 pmc_read_counter(struct kvm_pmc *pmc)
105{
106 u64 counter, enabled, running;
107
108 counter = pmc->counter + pmc->emulated_counter;
109
110 if (pmc->perf_event && !pmc->is_paused)
111 counter += perf_event_read_value(event: pmc->perf_event,
112 enabled: &enabled, running: &running);
113 /* FIXME: Scaling needed? */
114 return counter & pmc_bitmask(pmc);
115}
116
117void pmc_write_counter(struct kvm_pmc *pmc, u64 val);
118
119static inline bool pmc_is_gp(struct kvm_pmc *pmc)
120{
121 return pmc->type == KVM_PMC_GP;
122}
123
124static inline bool pmc_is_fixed(struct kvm_pmc *pmc)
125{
126 return pmc->type == KVM_PMC_FIXED;
127}
128
129static inline bool kvm_valid_perf_global_ctrl(struct kvm_pmu *pmu,
130 u64 data)
131{
132 return !(pmu->global_ctrl_mask & data);
133}
134
135/* returns general purpose PMC with the specified MSR. Note that it can be
136 * used for both PERFCTRn and EVNTSELn; that is why it accepts base as a
137 * parameter to tell them apart.
138 */
139static inline struct kvm_pmc *get_gp_pmc(struct kvm_pmu *pmu, u32 msr,
140 u32 base)
141{
142 if (msr >= base && msr < base + pmu->nr_arch_gp_counters) {
143 u32 index = array_index_nospec(msr - base,
144 pmu->nr_arch_gp_counters);
145
146 return &pmu->gp_counters[index];
147 }
148
149 return NULL;
150}
151
152/* returns fixed PMC with the specified MSR */
153static inline struct kvm_pmc *get_fixed_pmc(struct kvm_pmu *pmu, u32 msr)
154{
155 int base = MSR_CORE_PERF_FIXED_CTR0;
156
157 if (msr >= base && msr < base + pmu->nr_arch_fixed_counters) {
158 u32 index = array_index_nospec(msr - base,
159 pmu->nr_arch_fixed_counters);
160
161 return &pmu->fixed_counters[index];
162 }
163
164 return NULL;
165}
166
167static inline bool pmc_speculative_in_use(struct kvm_pmc *pmc)
168{
169 struct kvm_pmu *pmu = pmc_to_pmu(pmc);
170
171 if (pmc_is_fixed(pmc))
172 return fixed_ctrl_field(pmu->fixed_ctr_ctrl,
173 pmc->idx - KVM_FIXED_PMC_BASE_IDX) & 0x3;
174
175 return pmc->eventsel & ARCH_PERFMON_EVENTSEL_ENABLE;
176}
177
178extern struct x86_pmu_capability kvm_pmu_cap;
179extern struct kvm_pmu_emulated_event_selectors kvm_pmu_eventsel;
180
181static inline void kvm_init_pmu_capability(const struct kvm_pmu_ops *pmu_ops)
182{
183 bool is_intel = boot_cpu_data.x86_vendor == X86_VENDOR_INTEL;
184 int min_nr_gp_ctrs = pmu_ops->MIN_NR_GP_COUNTERS;
185
186 /*
187 * Hybrid PMUs don't play nice with virtualization without careful
188 * configuration by userspace, and KVM's APIs for reporting supported
189 * vPMU features do not account for hybrid PMUs. Disable vPMU support
190 * for hybrid PMUs until KVM gains a way to let userspace opt-in.
191 */
192 if (cpu_feature_enabled(X86_FEATURE_HYBRID_CPU))
193 enable_pmu = false;
194
195 if (enable_pmu) {
196 perf_get_x86_pmu_capability(cap: &kvm_pmu_cap);
197
198 /*
199 * WARN if perf did NOT disable hardware PMU if the number of
200 * architecturally required GP counters aren't present, i.e. if
201 * there are a non-zero number of counters, but fewer than what
202 * is architecturally required.
203 */
204 if (!kvm_pmu_cap.num_counters_gp ||
205 WARN_ON_ONCE(kvm_pmu_cap.num_counters_gp < min_nr_gp_ctrs))
206 enable_pmu = false;
207 else if (is_intel && !kvm_pmu_cap.version)
208 enable_pmu = false;
209 }
210
211 if (!enable_pmu) {
212 memset(&kvm_pmu_cap, 0, sizeof(kvm_pmu_cap));
213 return;
214 }
215
216 kvm_pmu_cap.version = min(kvm_pmu_cap.version, 2);
217 kvm_pmu_cap.num_counters_gp = min(kvm_pmu_cap.num_counters_gp,
218 pmu_ops->MAX_NR_GP_COUNTERS);
219 kvm_pmu_cap.num_counters_fixed = min(kvm_pmu_cap.num_counters_fixed,
220 KVM_PMC_MAX_FIXED);
221
222 kvm_pmu_eventsel.INSTRUCTIONS_RETIRED =
223 perf_get_hw_event_config(hw_event: PERF_COUNT_HW_INSTRUCTIONS);
224 kvm_pmu_eventsel.BRANCH_INSTRUCTIONS_RETIRED =
225 perf_get_hw_event_config(hw_event: PERF_COUNT_HW_BRANCH_INSTRUCTIONS);
226}
227
228static inline void kvm_pmu_request_counter_reprogram(struct kvm_pmc *pmc)
229{
230 set_bit(nr: pmc->idx, pmc_to_pmu(pmc)->reprogram_pmi);
231 kvm_make_request(KVM_REQ_PMU, vcpu: pmc->vcpu);
232}
233
234static inline void reprogram_counters(struct kvm_pmu *pmu, u64 diff)
235{
236 int bit;
237
238 if (!diff)
239 return;
240
241 for_each_set_bit(bit, (unsigned long *)&diff, X86_PMC_IDX_MAX)
242 set_bit(nr: bit, addr: pmu->reprogram_pmi);
243 kvm_make_request(KVM_REQ_PMU, pmu_to_vcpu(pmu));
244}
245
246/*
247 * Check if a PMC is enabled by comparing it against global_ctrl bits.
248 *
249 * If the vPMU doesn't have global_ctrl MSR, all vPMCs are enabled.
250 */
251static inline bool pmc_is_globally_enabled(struct kvm_pmc *pmc)
252{
253 struct kvm_pmu *pmu = pmc_to_pmu(pmc);
254
255 if (!kvm_pmu_has_perf_global_ctrl(pmu))
256 return true;
257
258 return test_bit(pmc->idx, (unsigned long *)&pmu->global_ctrl);
259}
260
261void kvm_pmu_deliver_pmi(struct kvm_vcpu *vcpu);
262void kvm_pmu_handle_event(struct kvm_vcpu *vcpu);
263int kvm_pmu_rdpmc(struct kvm_vcpu *vcpu, unsigned pmc, u64 *data);
264int kvm_pmu_check_rdpmc_early(struct kvm_vcpu *vcpu, unsigned int idx);
265bool kvm_pmu_is_valid_msr(struct kvm_vcpu *vcpu, u32 msr);
266int kvm_pmu_get_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info);
267int kvm_pmu_set_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info);
268void kvm_pmu_refresh(struct kvm_vcpu *vcpu);
269void kvm_pmu_init(struct kvm_vcpu *vcpu);
270void kvm_pmu_cleanup(struct kvm_vcpu *vcpu);
271void kvm_pmu_destroy(struct kvm_vcpu *vcpu);
272int kvm_vm_ioctl_set_pmu_event_filter(struct kvm *kvm, void __user *argp);
273void kvm_pmu_trigger_event(struct kvm_vcpu *vcpu, u64 eventsel);
274
275bool is_vmware_backdoor_pmc(u32 pmc_idx);
276
277extern struct kvm_pmu_ops intel_pmu_ops;
278extern struct kvm_pmu_ops amd_pmu_ops;
279#endif /* __KVM_X86_PMU_H */
280

source code of linux/arch/x86/kvm/pmu.h