xref: /linux/arch/x86/kvm/pmu.h (revision 9a4e47ef98a3041f6d2869ba2cd3401701776275)
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 #define vcpu_to_pmu(vcpu) (&(vcpu)->arch.pmu)
8 #define pmu_to_vcpu(pmu)  (container_of((pmu), struct kvm_vcpu, arch.pmu))
9 #define pmc_to_pmu(pmc)   (&(pmc)->vcpu->arch.pmu)
10 
11 #define MSR_IA32_MISC_ENABLE_PMU_RO_MASK (MSR_IA32_MISC_ENABLE_PEBS_UNAVAIL |	\
12 					  MSR_IA32_MISC_ENABLE_BTS_UNAVAIL)
13 
14 /* retrieve the 4 bits for EN and PMI out of IA32_FIXED_CTR_CTRL */
15 #define fixed_ctrl_field(ctrl_reg, idx) (((ctrl_reg) >> ((idx)*4)) & 0xf)
16 
17 #define VMWARE_BACKDOOR_PMC_HOST_TSC		0x10000
18 #define VMWARE_BACKDOOR_PMC_REAL_TIME		0x10001
19 #define VMWARE_BACKDOOR_PMC_APPARENT_TIME	0x10002
20 
21 struct kvm_pmu_ops {
22 	bool (*hw_event_available)(struct kvm_pmc *pmc);
23 	struct kvm_pmc *(*pmc_idx_to_pmc)(struct kvm_pmu *pmu, int pmc_idx);
24 	struct kvm_pmc *(*rdpmc_ecx_to_pmc)(struct kvm_vcpu *vcpu,
25 		unsigned int idx, u64 *mask);
26 	struct kvm_pmc *(*msr_idx_to_pmc)(struct kvm_vcpu *vcpu, u32 msr);
27 	bool (*is_valid_rdpmc_ecx)(struct kvm_vcpu *vcpu, unsigned int idx);
28 	bool (*is_valid_msr)(struct kvm_vcpu *vcpu, u32 msr);
29 	int (*get_msr)(struct kvm_vcpu *vcpu, struct msr_data *msr_info);
30 	int (*set_msr)(struct kvm_vcpu *vcpu, struct msr_data *msr_info);
31 	void (*refresh)(struct kvm_vcpu *vcpu);
32 	void (*init)(struct kvm_vcpu *vcpu);
33 	void (*reset)(struct kvm_vcpu *vcpu);
34 	void (*deliver_pmi)(struct kvm_vcpu *vcpu);
35 	void (*cleanup)(struct kvm_vcpu *vcpu);
36 
37 	const u64 EVENTSEL_EVENT;
38 	const int MAX_NR_GP_COUNTERS;
39 	const int MIN_NR_GP_COUNTERS;
40 };
41 
42 void kvm_pmu_ops_update(const struct kvm_pmu_ops *pmu_ops);
43 
44 static inline bool kvm_pmu_has_perf_global_ctrl(struct kvm_pmu *pmu)
45 {
46 	/*
47 	 * Architecturally, Intel's SDM states that IA32_PERF_GLOBAL_CTRL is
48 	 * supported if "CPUID.0AH: EAX[7:0] > 0", i.e. if the PMU version is
49 	 * greater than zero.  However, KVM only exposes and emulates the MSR
50 	 * to/for the guest if the guest PMU supports at least "Architectural
51 	 * Performance Monitoring Version 2".
52 	 *
53 	 * AMD's version of PERF_GLOBAL_CTRL conveniently shows up with v2.
54 	 */
55 	return pmu->version > 1;
56 }
57 
58 static inline u64 pmc_bitmask(struct kvm_pmc *pmc)
59 {
60 	struct kvm_pmu *pmu = pmc_to_pmu(pmc);
61 
62 	return pmu->counter_bitmask[pmc->type];
63 }
64 
65 static inline u64 pmc_read_counter(struct kvm_pmc *pmc)
66 {
67 	u64 counter, enabled, running;
68 
69 	counter = pmc->counter + pmc->emulated_counter;
70 
71 	if (pmc->perf_event && !pmc->is_paused)
72 		counter += perf_event_read_value(pmc->perf_event,
73 						 &enabled, &running);
74 	/* FIXME: Scaling needed? */
75 	return counter & pmc_bitmask(pmc);
76 }
77 
78 void pmc_write_counter(struct kvm_pmc *pmc, u64 val);
79 
80 static inline bool pmc_is_gp(struct kvm_pmc *pmc)
81 {
82 	return pmc->type == KVM_PMC_GP;
83 }
84 
85 static inline bool pmc_is_fixed(struct kvm_pmc *pmc)
86 {
87 	return pmc->type == KVM_PMC_FIXED;
88 }
89 
90 static inline bool kvm_valid_perf_global_ctrl(struct kvm_pmu *pmu,
91 						 u64 data)
92 {
93 	return !(pmu->global_ctrl_mask & data);
94 }
95 
96 /* returns general purpose PMC with the specified MSR. Note that it can be
97  * used for both PERFCTRn and EVNTSELn; that is why it accepts base as a
98  * parameter to tell them apart.
99  */
100 static inline struct kvm_pmc *get_gp_pmc(struct kvm_pmu *pmu, u32 msr,
101 					 u32 base)
102 {
103 	if (msr >= base && msr < base + pmu->nr_arch_gp_counters) {
104 		u32 index = array_index_nospec(msr - base,
105 					       pmu->nr_arch_gp_counters);
106 
107 		return &pmu->gp_counters[index];
108 	}
109 
110 	return NULL;
111 }
112 
113 /* returns fixed PMC with the specified MSR */
114 static inline struct kvm_pmc *get_fixed_pmc(struct kvm_pmu *pmu, u32 msr)
115 {
116 	int base = MSR_CORE_PERF_FIXED_CTR0;
117 
118 	if (msr >= base && msr < base + pmu->nr_arch_fixed_counters) {
119 		u32 index = array_index_nospec(msr - base,
120 					       pmu->nr_arch_fixed_counters);
121 
122 		return &pmu->fixed_counters[index];
123 	}
124 
125 	return NULL;
126 }
127 
128 static inline bool pmc_speculative_in_use(struct kvm_pmc *pmc)
129 {
130 	struct kvm_pmu *pmu = pmc_to_pmu(pmc);
131 
132 	if (pmc_is_fixed(pmc))
133 		return fixed_ctrl_field(pmu->fixed_ctr_ctrl,
134 					pmc->idx - INTEL_PMC_IDX_FIXED) & 0x3;
135 
136 	return pmc->eventsel & ARCH_PERFMON_EVENTSEL_ENABLE;
137 }
138 
139 extern struct x86_pmu_capability kvm_pmu_cap;
140 
141 static inline void kvm_init_pmu_capability(const struct kvm_pmu_ops *pmu_ops)
142 {
143 	bool is_intel = boot_cpu_data.x86_vendor == X86_VENDOR_INTEL;
144 	int min_nr_gp_ctrs = pmu_ops->MIN_NR_GP_COUNTERS;
145 
146 	/*
147 	 * Hybrid PMUs don't play nice with virtualization without careful
148 	 * configuration by userspace, and KVM's APIs for reporting supported
149 	 * vPMU features do not account for hybrid PMUs.  Disable vPMU support
150 	 * for hybrid PMUs until KVM gains a way to let userspace opt-in.
151 	 */
152 	if (cpu_feature_enabled(X86_FEATURE_HYBRID_CPU))
153 		enable_pmu = false;
154 
155 	if (enable_pmu) {
156 		perf_get_x86_pmu_capability(&kvm_pmu_cap);
157 
158 		/*
159 		 * WARN if perf did NOT disable hardware PMU if the number of
160 		 * architecturally required GP counters aren't present, i.e. if
161 		 * there are a non-zero number of counters, but fewer than what
162 		 * is architecturally required.
163 		 */
164 		if (!kvm_pmu_cap.num_counters_gp ||
165 		    WARN_ON_ONCE(kvm_pmu_cap.num_counters_gp < min_nr_gp_ctrs))
166 			enable_pmu = false;
167 		else if (is_intel && !kvm_pmu_cap.version)
168 			enable_pmu = false;
169 	}
170 
171 	if (!enable_pmu) {
172 		memset(&kvm_pmu_cap, 0, sizeof(kvm_pmu_cap));
173 		return;
174 	}
175 
176 	kvm_pmu_cap.version = min(kvm_pmu_cap.version, 2);
177 	kvm_pmu_cap.num_counters_gp = min(kvm_pmu_cap.num_counters_gp,
178 					  pmu_ops->MAX_NR_GP_COUNTERS);
179 	kvm_pmu_cap.num_counters_fixed = min(kvm_pmu_cap.num_counters_fixed,
180 					     KVM_PMC_MAX_FIXED);
181 }
182 
183 static inline void kvm_pmu_request_counter_reprogram(struct kvm_pmc *pmc)
184 {
185 	set_bit(pmc->idx, pmc_to_pmu(pmc)->reprogram_pmi);
186 	kvm_make_request(KVM_REQ_PMU, pmc->vcpu);
187 }
188 
189 static inline void reprogram_counters(struct kvm_pmu *pmu, u64 diff)
190 {
191 	int bit;
192 
193 	if (!diff)
194 		return;
195 
196 	for_each_set_bit(bit, (unsigned long *)&diff, X86_PMC_IDX_MAX)
197 		set_bit(bit, pmu->reprogram_pmi);
198 	kvm_make_request(KVM_REQ_PMU, pmu_to_vcpu(pmu));
199 }
200 
201 /*
202  * Check if a PMC is enabled by comparing it against global_ctrl bits.
203  *
204  * If the vPMU doesn't have global_ctrl MSR, all vPMCs are enabled.
205  */
206 static inline bool pmc_is_globally_enabled(struct kvm_pmc *pmc)
207 {
208 	struct kvm_pmu *pmu = pmc_to_pmu(pmc);
209 
210 	if (!kvm_pmu_has_perf_global_ctrl(pmu))
211 		return true;
212 
213 	return test_bit(pmc->idx, (unsigned long *)&pmu->global_ctrl);
214 }
215 
216 void kvm_pmu_deliver_pmi(struct kvm_vcpu *vcpu);
217 void kvm_pmu_handle_event(struct kvm_vcpu *vcpu);
218 int kvm_pmu_rdpmc(struct kvm_vcpu *vcpu, unsigned pmc, u64 *data);
219 bool kvm_pmu_is_valid_rdpmc_ecx(struct kvm_vcpu *vcpu, unsigned int idx);
220 bool kvm_pmu_is_valid_msr(struct kvm_vcpu *vcpu, u32 msr);
221 int kvm_pmu_get_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info);
222 int kvm_pmu_set_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info);
223 void kvm_pmu_refresh(struct kvm_vcpu *vcpu);
224 void kvm_pmu_init(struct kvm_vcpu *vcpu);
225 void kvm_pmu_cleanup(struct kvm_vcpu *vcpu);
226 void kvm_pmu_destroy(struct kvm_vcpu *vcpu);
227 int kvm_vm_ioctl_set_pmu_event_filter(struct kvm *kvm, void __user *argp);
228 void kvm_pmu_trigger_event(struct kvm_vcpu *vcpu, u64 perf_hw_id);
229 
230 bool is_vmware_backdoor_pmc(u32 pmc_idx);
231 
232 extern struct kvm_pmu_ops intel_pmu_ops;
233 extern struct kvm_pmu_ops amd_pmu_ops;
234 #endif /* __KVM_X86_PMU_H */
235