xref: /linux/arch/x86/kvm/pmu.h (revision f7a65e58d64340c3c0e390ea4e1c4857cd451f1f)
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 a fixed counter bits 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_ops {
27 	struct kvm_pmc *(*rdpmc_ecx_to_pmc)(struct kvm_vcpu *vcpu,
28 		unsigned int idx, u64 *mask);
29 	struct kvm_pmc *(*msr_idx_to_pmc)(struct kvm_vcpu *vcpu, u32 msr);
30 	int (*check_rdpmc_early)(struct kvm_vcpu *vcpu, unsigned int idx);
31 	bool (*is_valid_msr)(struct kvm_vcpu *vcpu, u32 msr);
32 	int (*get_msr)(struct kvm_vcpu *vcpu, struct msr_data *msr_info);
33 	int (*set_msr)(struct kvm_vcpu *vcpu, struct msr_data *msr_info);
34 	void (*refresh)(struct kvm_vcpu *vcpu);
35 	void (*init)(struct kvm_vcpu *vcpu);
36 	void (*reset)(struct kvm_vcpu *vcpu);
37 	void (*deliver_pmi)(struct kvm_vcpu *vcpu);
38 	void (*cleanup)(struct kvm_vcpu *vcpu);
39 
40 	bool (*is_mediated_pmu_supported)(struct x86_pmu_capability *host_pmu);
41 	void (*mediated_load)(struct kvm_vcpu *vcpu);
42 	void (*mediated_put)(struct kvm_vcpu *vcpu);
43 	void (*write_global_ctrl)(u64 global_ctrl);
44 
45 	const u64 EVENTSEL_EVENT;
46 	const int MAX_NR_GP_COUNTERS;
47 	const int MIN_NR_GP_COUNTERS;
48 
49 	const u32 PERF_GLOBAL_CTRL;
50 	const u32 GP_EVENTSEL_BASE;
51 	const u32 GP_COUNTER_BASE;
52 	const u32 FIXED_COUNTER_BASE;
53 	const u32 MSR_STRIDE;
54 };
55 
56 void kvm_pmu_ops_update(const struct kvm_pmu_ops *pmu_ops);
57 
58 void kvm_handle_guest_mediated_pmi(void);
59 
60 static inline bool kvm_pmu_has_perf_global_ctrl(struct kvm_pmu *pmu)
61 {
62 	/*
63 	 * Architecturally, Intel's SDM states that IA32_PERF_GLOBAL_CTRL is
64 	 * supported if "CPUID.0AH: EAX[7:0] > 0", i.e. if the PMU version is
65 	 * greater than zero.  However, KVM only exposes and emulates the MSR
66 	 * to/for the guest if the guest PMU supports at least "Architectural
67 	 * Performance Monitoring Version 2".
68 	 *
69 	 * AMD's version of PERF_GLOBAL_CTRL conveniently shows up with v2.
70 	 */
71 	return pmu->version > 1;
72 }
73 
74 static inline bool kvm_vcpu_has_mediated_pmu(struct kvm_vcpu *vcpu)
75 {
76 	return enable_mediated_pmu && vcpu_to_pmu(vcpu)->version;
77 }
78 
79 /*
80  * KVM tracks all counters in 64-bit bitmaps, with general purpose counters
81  * mapped to bits 31:0 and fixed counters mapped to 63:32, e.g. fixed counter 0
82  * is tracked internally via index 32.  On Intel, (AMD doesn't support fixed
83  * counters), this mirrors how fixed counters are mapped to PERF_GLOBAL_CTRL
84  * and similar MSRs, i.e. tracking fixed counters at base index 32 reduces the
85  * amounter of boilerplate needed to iterate over PMCs *and* simplifies common
86  * enabling/disable/reset operations.
87  *
88  * WARNING!  This helper is only for lookups that are initiated by KVM, it is
89  * NOT safe for guest lookups, e.g. will do the wrong thing if passed a raw
90  * ECX value from RDPMC (fixed counters are accessed by setting bit 30 in ECX
91  * for RDPMC, not by adding 32 to the fixed counter index).
92  */
93 static inline struct kvm_pmc *kvm_pmc_idx_to_pmc(struct kvm_pmu *pmu, int idx)
94 {
95 	if (idx < pmu->nr_arch_gp_counters)
96 		return &pmu->gp_counters[idx];
97 
98 	idx -= KVM_FIXED_PMC_BASE_IDX;
99 	if (idx >= 0 && idx < pmu->nr_arch_fixed_counters)
100 		return &pmu->fixed_counters[idx];
101 
102 	return NULL;
103 }
104 
105 #define kvm_for_each_pmc(pmu, pmc, i, bitmap)			\
106 	for_each_set_bit(i, bitmap, X86_PMC_IDX_MAX)		\
107 		if (!(pmc = kvm_pmc_idx_to_pmc(pmu, i)))	\
108 			continue;				\
109 		else						\
110 
111 static inline u64 pmc_bitmask(struct kvm_pmc *pmc)
112 {
113 	struct kvm_pmu *pmu = pmc_to_pmu(pmc);
114 
115 	return pmu->counter_bitmask[pmc->type];
116 }
117 
118 static inline u64 pmc_read_counter(struct kvm_pmc *pmc)
119 {
120 	u64 counter, enabled, running;
121 
122 	if (kvm_vcpu_has_mediated_pmu(pmc->vcpu))
123 		return pmc->counter & pmc_bitmask(pmc);
124 
125 	counter = pmc->counter + pmc->emulated_counter;
126 
127 	if (pmc->perf_event && !pmc->is_paused)
128 		counter += perf_event_read_value(pmc->perf_event,
129 						 &enabled, &running);
130 	/* FIXME: Scaling needed? */
131 	return counter & pmc_bitmask(pmc);
132 }
133 
134 void pmc_write_counter(struct kvm_pmc *pmc, u64 val);
135 
136 static inline bool pmc_is_gp(struct kvm_pmc *pmc)
137 {
138 	return pmc->type == KVM_PMC_GP;
139 }
140 
141 static inline bool pmc_is_fixed(struct kvm_pmc *pmc)
142 {
143 	return pmc->type == KVM_PMC_FIXED;
144 }
145 
146 static inline bool kvm_valid_perf_global_ctrl(struct kvm_pmu *pmu,
147 						 u64 data)
148 {
149 	return !(pmu->global_ctrl_rsvd & data);
150 }
151 
152 /* returns general purpose PMC with the specified MSR. Note that it can be
153  * used for both PERFCTRn and EVNTSELn; that is why it accepts base as a
154  * parameter to tell them apart.
155  */
156 static inline struct kvm_pmc *get_gp_pmc(struct kvm_pmu *pmu, u32 msr,
157 					 u32 base)
158 {
159 	if (msr >= base && msr < base + pmu->nr_arch_gp_counters) {
160 		u32 index = array_index_nospec(msr - base,
161 					       pmu->nr_arch_gp_counters);
162 
163 		return &pmu->gp_counters[index];
164 	}
165 
166 	return NULL;
167 }
168 
169 /* returns fixed PMC with the specified MSR */
170 static inline struct kvm_pmc *get_fixed_pmc(struct kvm_pmu *pmu, u32 msr)
171 {
172 	int base = MSR_CORE_PERF_FIXED_CTR0;
173 
174 	if (msr >= base && msr < base + pmu->nr_arch_fixed_counters) {
175 		u32 index = array_index_nospec(msr - base,
176 					       pmu->nr_arch_fixed_counters);
177 
178 		return &pmu->fixed_counters[index];
179 	}
180 
181 	return NULL;
182 }
183 
184 static inline bool pmc_is_locally_enabled(struct kvm_pmc *pmc)
185 {
186 	struct kvm_pmu *pmu = pmc_to_pmu(pmc);
187 
188 	if (pmc_is_fixed(pmc))
189 		return fixed_ctrl_field(pmu->fixed_ctr_ctrl,
190 					pmc->idx - KVM_FIXED_PMC_BASE_IDX) &
191 					(INTEL_FIXED_0_KERNEL | INTEL_FIXED_0_USER);
192 
193 	return pmc->eventsel & ARCH_PERFMON_EVENTSEL_ENABLE;
194 }
195 
196 extern struct x86_pmu_capability kvm_pmu_cap;
197 
198 void kvm_init_pmu_capability(struct kvm_pmu_ops *pmu_ops);
199 
200 void kvm_pmu_recalc_pmc_emulation(struct kvm_pmu *pmu, struct kvm_pmc *pmc);
201 
202 static inline void kvm_pmu_request_counter_reprogram(struct kvm_pmc *pmc)
203 {
204 	kvm_pmu_recalc_pmc_emulation(pmc_to_pmu(pmc), pmc);
205 
206 	set_bit(pmc->idx, pmc_to_pmu(pmc)->reprogram_pmi);
207 	kvm_make_request(KVM_REQ_PMU, pmc->vcpu);
208 }
209 
210 static inline void reprogram_counters(struct kvm_pmu *pmu, u64 diff)
211 {
212 	int bit;
213 
214 	if (!diff)
215 		return;
216 
217 	for_each_set_bit(bit, (unsigned long *)&diff, X86_PMC_IDX_MAX)
218 		set_bit(bit, pmu->reprogram_pmi);
219 	kvm_make_request(KVM_REQ_PMU, pmu_to_vcpu(pmu));
220 }
221 
222 /*
223  * Check if a PMC is enabled by comparing it against global_ctrl bits.
224  *
225  * If the vPMU doesn't have global_ctrl MSR, all vPMCs are enabled.
226  */
227 static inline bool pmc_is_globally_enabled(struct kvm_pmc *pmc)
228 {
229 	struct kvm_pmu *pmu = pmc_to_pmu(pmc);
230 
231 	if (!kvm_pmu_has_perf_global_ctrl(pmu))
232 		return true;
233 
234 	return test_bit(pmc->idx, (unsigned long *)&pmu->global_ctrl);
235 }
236 
237 static inline bool kvm_pmu_is_fastpath_emulation_allowed(struct kvm_vcpu *vcpu)
238 {
239 	struct kvm_pmu *pmu = vcpu_to_pmu(vcpu);
240 
241 	return !kvm_vcpu_has_mediated_pmu(vcpu) ||
242 	       !bitmap_intersects(pmu->pmc_counting_instructions,
243 				  (unsigned long *)&pmu->global_ctrl,
244 				  X86_PMC_IDX_MAX);
245 }
246 
247 void kvm_pmu_deliver_pmi(struct kvm_vcpu *vcpu);
248 void kvm_pmu_handle_event(struct kvm_vcpu *vcpu);
249 int kvm_pmu_rdpmc(struct kvm_vcpu *vcpu, unsigned pmc, u64 *data);
250 int kvm_pmu_check_rdpmc_early(struct kvm_vcpu *vcpu, unsigned int idx);
251 bool kvm_pmu_is_valid_msr(struct kvm_vcpu *vcpu, u32 msr);
252 int kvm_pmu_get_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info);
253 int kvm_pmu_set_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info);
254 void kvm_pmu_refresh(struct kvm_vcpu *vcpu);
255 void kvm_pmu_init(struct kvm_vcpu *vcpu);
256 void kvm_pmu_cleanup(struct kvm_vcpu *vcpu);
257 void kvm_pmu_destroy(struct kvm_vcpu *vcpu);
258 int kvm_vm_ioctl_set_pmu_event_filter(struct kvm *kvm, void __user *argp);
259 void kvm_pmu_instruction_retired(struct kvm_vcpu *vcpu);
260 void kvm_pmu_branch_retired(struct kvm_vcpu *vcpu);
261 void kvm_mediated_pmu_load(struct kvm_vcpu *vcpu);
262 void kvm_mediated_pmu_put(struct kvm_vcpu *vcpu);
263 
264 bool is_vmware_backdoor_pmc(u32 pmc_idx);
265 bool kvm_need_perf_global_ctrl_intercept(struct kvm_vcpu *vcpu);
266 bool kvm_need_rdpmc_intercept(struct kvm_vcpu *vcpu);
267 
268 extern struct kvm_pmu_ops intel_pmu_ops;
269 extern struct kvm_pmu_ops amd_pmu_ops;
270 #endif /* __KVM_X86_PMU_H */
271