xref: /openbmc/linux/arch/x86/kvm/pmu.h (revision 709f34b4)
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 	bool (*pmc_is_enabled)(struct kvm_pmc *pmc);
24 	struct kvm_pmc *(*pmc_idx_to_pmc)(struct kvm_pmu *pmu, int pmc_idx);
25 	struct kvm_pmc *(*rdpmc_ecx_to_pmc)(struct kvm_vcpu *vcpu,
26 		unsigned int idx, u64 *mask);
27 	struct kvm_pmc *(*msr_idx_to_pmc)(struct kvm_vcpu *vcpu, u32 msr);
28 	bool (*is_valid_rdpmc_ecx)(struct kvm_vcpu *vcpu, unsigned int idx);
29 	bool (*is_valid_msr)(struct kvm_vcpu *vcpu, u32 msr);
30 	int (*get_msr)(struct kvm_vcpu *vcpu, struct msr_data *msr_info);
31 	int (*set_msr)(struct kvm_vcpu *vcpu, struct msr_data *msr_info);
32 	void (*refresh)(struct kvm_vcpu *vcpu);
33 	void (*init)(struct kvm_vcpu *vcpu);
34 	void (*reset)(struct kvm_vcpu *vcpu);
35 	void (*deliver_pmi)(struct kvm_vcpu *vcpu);
36 	void (*cleanup)(struct kvm_vcpu *vcpu);
37 
38 	const u64 EVENTSEL_EVENT;
39 	const int MAX_NR_GP_COUNTERS;
40 };
41 
42 void kvm_pmu_ops_update(const struct kvm_pmu_ops *pmu_ops);
43 
44 static inline u64 pmc_bitmask(struct kvm_pmc *pmc)
45 {
46 	struct kvm_pmu *pmu = pmc_to_pmu(pmc);
47 
48 	return pmu->counter_bitmask[pmc->type];
49 }
50 
51 static inline u64 pmc_read_counter(struct kvm_pmc *pmc)
52 {
53 	u64 counter, enabled, running;
54 
55 	counter = pmc->counter;
56 	if (pmc->perf_event && !pmc->is_paused)
57 		counter += perf_event_read_value(pmc->perf_event,
58 						 &enabled, &running);
59 	/* FIXME: Scaling needed? */
60 	return counter & pmc_bitmask(pmc);
61 }
62 
63 static inline void pmc_release_perf_event(struct kvm_pmc *pmc)
64 {
65 	if (pmc->perf_event) {
66 		perf_event_release_kernel(pmc->perf_event);
67 		pmc->perf_event = NULL;
68 		pmc->current_config = 0;
69 		pmc_to_pmu(pmc)->event_count--;
70 	}
71 }
72 
73 static inline void pmc_stop_counter(struct kvm_pmc *pmc)
74 {
75 	if (pmc->perf_event) {
76 		pmc->counter = pmc_read_counter(pmc);
77 		pmc_release_perf_event(pmc);
78 	}
79 }
80 
81 static inline bool pmc_is_gp(struct kvm_pmc *pmc)
82 {
83 	return pmc->type == KVM_PMC_GP;
84 }
85 
86 static inline bool pmc_is_fixed(struct kvm_pmc *pmc)
87 {
88 	return pmc->type == KVM_PMC_FIXED;
89 }
90 
91 static inline bool kvm_valid_perf_global_ctrl(struct kvm_pmu *pmu,
92 						 u64 data)
93 {
94 	return !(pmu->global_ctrl_mask & data);
95 }
96 
97 /* returns general purpose PMC with the specified MSR. Note that it can be
98  * used for both PERFCTRn and EVNTSELn; that is why it accepts base as a
99  * parameter to tell them apart.
100  */
101 static inline struct kvm_pmc *get_gp_pmc(struct kvm_pmu *pmu, u32 msr,
102 					 u32 base)
103 {
104 	if (msr >= base && msr < base + pmu->nr_arch_gp_counters) {
105 		u32 index = array_index_nospec(msr - base,
106 					       pmu->nr_arch_gp_counters);
107 
108 		return &pmu->gp_counters[index];
109 	}
110 
111 	return NULL;
112 }
113 
114 /* returns fixed PMC with the specified MSR */
115 static inline struct kvm_pmc *get_fixed_pmc(struct kvm_pmu *pmu, u32 msr)
116 {
117 	int base = MSR_CORE_PERF_FIXED_CTR0;
118 
119 	if (msr >= base && msr < base + pmu->nr_arch_fixed_counters) {
120 		u32 index = array_index_nospec(msr - base,
121 					       pmu->nr_arch_fixed_counters);
122 
123 		return &pmu->fixed_counters[index];
124 	}
125 
126 	return NULL;
127 }
128 
129 static inline u64 get_sample_period(struct kvm_pmc *pmc, u64 counter_value)
130 {
131 	u64 sample_period = (-counter_value) & pmc_bitmask(pmc);
132 
133 	if (!sample_period)
134 		sample_period = pmc_bitmask(pmc) + 1;
135 	return sample_period;
136 }
137 
138 static inline void pmc_update_sample_period(struct kvm_pmc *pmc)
139 {
140 	if (!pmc->perf_event || pmc->is_paused ||
141 	    !is_sampling_event(pmc->perf_event))
142 		return;
143 
144 	perf_event_period(pmc->perf_event,
145 			  get_sample_period(pmc, pmc->counter));
146 }
147 
148 static inline bool pmc_speculative_in_use(struct kvm_pmc *pmc)
149 {
150 	struct kvm_pmu *pmu = pmc_to_pmu(pmc);
151 
152 	if (pmc_is_fixed(pmc))
153 		return fixed_ctrl_field(pmu->fixed_ctr_ctrl,
154 					pmc->idx - INTEL_PMC_IDX_FIXED) & 0x3;
155 
156 	return pmc->eventsel & ARCH_PERFMON_EVENTSEL_ENABLE;
157 }
158 
159 extern struct x86_pmu_capability kvm_pmu_cap;
160 
161 static inline void kvm_init_pmu_capability(const struct kvm_pmu_ops *pmu_ops)
162 {
163 	bool is_intel = boot_cpu_data.x86_vendor == X86_VENDOR_INTEL;
164 
165 	/*
166 	 * Hybrid PMUs don't play nice with virtualization without careful
167 	 * configuration by userspace, and KVM's APIs for reporting supported
168 	 * vPMU features do not account for hybrid PMUs.  Disable vPMU support
169 	 * for hybrid PMUs until KVM gains a way to let userspace opt-in.
170 	 */
171 	if (cpu_feature_enabled(X86_FEATURE_HYBRID_CPU))
172 		enable_pmu = false;
173 
174 	if (enable_pmu) {
175 		perf_get_x86_pmu_capability(&kvm_pmu_cap);
176 
177 		/*
178 		 * For Intel, only support guest architectural pmu
179 		 * on a host with architectural pmu.
180 		 */
181 		if ((is_intel && !kvm_pmu_cap.version) ||
182 		    !kvm_pmu_cap.num_counters_gp)
183 			enable_pmu = false;
184 	}
185 
186 	if (!enable_pmu) {
187 		memset(&kvm_pmu_cap, 0, sizeof(kvm_pmu_cap));
188 		return;
189 	}
190 
191 	kvm_pmu_cap.version = min(kvm_pmu_cap.version, 2);
192 	kvm_pmu_cap.num_counters_gp = min(kvm_pmu_cap.num_counters_gp,
193 					  pmu_ops->MAX_NR_GP_COUNTERS);
194 	kvm_pmu_cap.num_counters_fixed = min(kvm_pmu_cap.num_counters_fixed,
195 					     KVM_PMC_MAX_FIXED);
196 }
197 
198 static inline void kvm_pmu_request_counter_reprogram(struct kvm_pmc *pmc)
199 {
200 	set_bit(pmc->idx, pmc_to_pmu(pmc)->reprogram_pmi);
201 	kvm_make_request(KVM_REQ_PMU, pmc->vcpu);
202 }
203 
204 void kvm_pmu_deliver_pmi(struct kvm_vcpu *vcpu);
205 void kvm_pmu_handle_event(struct kvm_vcpu *vcpu);
206 int kvm_pmu_rdpmc(struct kvm_vcpu *vcpu, unsigned pmc, u64 *data);
207 bool kvm_pmu_is_valid_rdpmc_ecx(struct kvm_vcpu *vcpu, unsigned int idx);
208 bool kvm_pmu_is_valid_msr(struct kvm_vcpu *vcpu, u32 msr);
209 int kvm_pmu_get_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info);
210 int kvm_pmu_set_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info);
211 void kvm_pmu_refresh(struct kvm_vcpu *vcpu);
212 void kvm_pmu_reset(struct kvm_vcpu *vcpu);
213 void kvm_pmu_init(struct kvm_vcpu *vcpu);
214 void kvm_pmu_cleanup(struct kvm_vcpu *vcpu);
215 void kvm_pmu_destroy(struct kvm_vcpu *vcpu);
216 int kvm_vm_ioctl_set_pmu_event_filter(struct kvm *kvm, void __user *argp);
217 void kvm_pmu_trigger_event(struct kvm_vcpu *vcpu, u64 perf_hw_id);
218 
219 bool is_vmware_backdoor_pmc(u32 pmc_idx);
220 
221 extern struct kvm_pmu_ops intel_pmu_ops;
222 extern struct kvm_pmu_ops amd_pmu_ops;
223 #endif /* __KVM_X86_PMU_H */
224