xref: /linux/arch/x86/kvm/pmu.h (revision 3a2c4d55e32ad65efebdb6de44eef3bfa08bb49d)
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 	bool (*pmc_is_disabled_in_current_mode)(struct kvm_pmc *pmc);
40 
41 	bool (*is_mediated_pmu_supported)(struct x86_pmu_capability *host_pmu);
42 	void (*mediated_load)(struct kvm_vcpu *vcpu);
43 	void (*mediated_put)(struct kvm_vcpu *vcpu);
44 	void (*write_global_ctrl)(u64 global_ctrl);
45 
46 	const u64 EVENTSEL_EVENT;
47 	const int MAX_NR_GP_COUNTERS;
48 	const int MIN_NR_GP_COUNTERS;
49 
50 	const u32 PERF_GLOBAL_CTRL;
51 	const u32 GP_EVENTSEL_BASE;
52 	const u32 GP_COUNTER_BASE;
53 	const u32 FIXED_COUNTER_BASE;
54 	const u32 MSR_STRIDE;
55 };
56 
57 #define kvm_pmu_call(func) static_call(kvm_x86_pmu_##func)
58 
59 #define KVM_X86_PMU_OP(func) \
60 	DECLARE_STATIC_CALL(kvm_x86_pmu_##func, *(((struct kvm_pmu_ops *)0)->func));
61 #define KVM_X86_PMU_OP_OPTIONAL KVM_X86_PMU_OP
62 #define KVM_X86_PMU_OP_OPTIONAL_RET0 KVM_X86_PMU_OP
63 #include <asm/kvm-x86-pmu-ops.h>
64 
65 extern bool enable_pmu;
66 extern bool enable_mediated_pmu;
67 
68 void kvm_pmu_ops_update(const struct kvm_pmu_ops *pmu_ops);
69 
70 void kvm_handle_guest_mediated_pmi(void);
71 
72 static inline bool kvm_pmu_has_perf_global_ctrl(struct kvm_pmu *pmu)
73 {
74 	/*
75 	 * Architecturally, Intel's SDM states that IA32_PERF_GLOBAL_CTRL is
76 	 * supported if "CPUID.0AH: EAX[7:0] > 0", i.e. if the PMU version is
77 	 * greater than zero.  However, KVM only exposes and emulates the MSR
78 	 * to/for the guest if the guest PMU supports at least "Architectural
79 	 * Performance Monitoring Version 2".
80 	 *
81 	 * AMD's version of PERF_GLOBAL_CTRL conveniently shows up with v2.
82 	 */
83 	return pmu->version > 1;
84 }
85 
86 static inline bool kvm_vcpu_has_mediated_pmu(struct kvm_vcpu *vcpu)
87 {
88 	return enable_mediated_pmu && vcpu_to_pmu(vcpu)->version;
89 }
90 
91 /*
92  * KVM tracks all counters in 64-bit bitmaps, with general purpose counters
93  * mapped to bits 31:0 and fixed counters mapped to 63:32, e.g. fixed counter 0
94  * is tracked internally via index 32.  On Intel, (AMD doesn't support fixed
95  * counters), this mirrors how fixed counters are mapped to PERF_GLOBAL_CTRL
96  * and similar MSRs, i.e. tracking fixed counters at base index 32 reduces the
97  * amount of boilerplate needed to iterate over PMCs *and* simplifies common
98  * enable/disable/reset operations.
99  *
100  * WARNING!  This helper is only for lookups that are initiated by KVM, it is
101  * NOT safe for guest lookups, e.g. will do the wrong thing if passed a raw
102  * ECX value from RDPMC (fixed counters are accessed by setting bit 30 in ECX
103  * for RDPMC, not by adding 32 to the fixed counter index).
104  */
105 static inline struct kvm_pmc *kvm_pmc_idx_to_pmc(struct kvm_pmu *pmu, int idx)
106 {
107 	if (idx < pmu->nr_arch_gp_counters)
108 		return &pmu->gp_counters[idx];
109 
110 	idx -= KVM_FIXED_PMC_BASE_IDX;
111 	if (idx >= 0 && idx < pmu->nr_arch_fixed_counters)
112 		return &pmu->fixed_counters[idx];
113 
114 	return NULL;
115 }
116 
117 #define kvm_for_each_pmc(pmu, pmc, i, bitmap)			\
118 	for_each_set_bit(i, bitmap, X86_PMC_IDX_MAX)		\
119 		if (!(pmc = kvm_pmc_idx_to_pmc(pmu, i)))	\
120 			continue;				\
121 		else						\
122 
123 static inline u64 pmc_bitmask(struct kvm_pmc *pmc)
124 {
125 	struct kvm_pmu *pmu = pmc_to_pmu(pmc);
126 
127 	return pmu->counter_bitmask[pmc->type];
128 }
129 
130 static inline u64 pmc_read_counter(struct kvm_pmc *pmc)
131 {
132 	u64 counter, enabled, running;
133 
134 	if (kvm_vcpu_has_mediated_pmu(pmc->vcpu))
135 		return pmc->counter & pmc_bitmask(pmc);
136 
137 	counter = pmc->counter + pmc->emulated_counter;
138 
139 	if (pmc->perf_event && !pmc->is_paused)
140 		counter += perf_event_read_value(pmc->perf_event,
141 						 &enabled, &running);
142 	/* FIXME: Scaling needed? */
143 	return counter & pmc_bitmask(pmc);
144 }
145 
146 void pmc_write_counter(struct kvm_pmc *pmc, u64 val);
147 
148 static inline bool pmc_is_gp(struct kvm_pmc *pmc)
149 {
150 	return pmc->type == KVM_PMC_GP;
151 }
152 
153 static inline bool pmc_is_fixed(struct kvm_pmc *pmc)
154 {
155 	return pmc->type == KVM_PMC_FIXED;
156 }
157 
158 static inline bool kvm_valid_perf_global_ctrl(struct kvm_pmu *pmu,
159 						 u64 data)
160 {
161 	return !(pmu->global_ctrl_rsvd & data);
162 }
163 
164 /* returns general purpose PMC with the specified MSR. Note that it can be
165  * used for both PERFCTRn and EVNTSELn; that is why it accepts base as a
166  * parameter to tell them apart.
167  */
168 static inline struct kvm_pmc *get_gp_pmc(struct kvm_pmu *pmu, u32 msr,
169 					 u32 base)
170 {
171 	if (msr >= base && msr < base + pmu->nr_arch_gp_counters) {
172 		u32 index = array_index_nospec(msr - base,
173 					       pmu->nr_arch_gp_counters);
174 
175 		return &pmu->gp_counters[index];
176 	}
177 
178 	return NULL;
179 }
180 
181 /* returns fixed PMC with the specified MSR */
182 static inline struct kvm_pmc *get_fixed_pmc(struct kvm_pmu *pmu, u32 msr)
183 {
184 	int base = MSR_CORE_PERF_FIXED_CTR0;
185 
186 	if (msr >= base && msr < base + pmu->nr_arch_fixed_counters) {
187 		u32 index = array_index_nospec(msr - base,
188 					       pmu->nr_arch_fixed_counters);
189 
190 		return &pmu->fixed_counters[index];
191 	}
192 
193 	return NULL;
194 }
195 
196 static inline bool pmc_is_locally_enabled(struct kvm_pmc *pmc)
197 {
198 	struct kvm_pmu *pmu = pmc_to_pmu(pmc);
199 
200 	if (pmc_is_fixed(pmc))
201 		return fixed_ctrl_field(pmu->fixed_ctr_ctrl,
202 					pmc->idx - KVM_FIXED_PMC_BASE_IDX) &
203 					(INTEL_FIXED_0_KERNEL | INTEL_FIXED_0_USER);
204 
205 	if (!(pmc->eventsel & ARCH_PERFMON_EVENTSEL_ENABLE))
206 		return false;
207 
208 	if (!test_bit(pmc->idx, pmu->pmc_has_mode_specific_enables))
209 		return true;
210 
211 	return !kvm_pmu_call(pmc_is_disabled_in_current_mode)(pmc);
212 }
213 
214 extern struct x86_pmu_capability kvm_pmu_cap;
215 
216 void kvm_init_pmu_capability(struct kvm_pmu_ops *pmu_ops);
217 
218 void kvm_pmu_recalc_pmc_emulation(struct kvm_pmu *pmu, struct kvm_pmc *pmc);
219 void kvm_pmu_handle_event(struct kvm_vcpu *vcpu);
220 
221 static inline void kvm_pmu_request_counter_reprogram(struct kvm_pmc *pmc)
222 {
223 	kvm_pmu_recalc_pmc_emulation(pmc_to_pmu(pmc), pmc);
224 
225 	set_bit(pmc->idx, pmc_to_pmu(pmc)->reprogram_pmi);
226 	kvm_make_request(KVM_REQ_PMU, pmc->vcpu);
227 }
228 
229 static inline void __kvm_pmu_reprogram_counters(struct kvm_pmu *pmu,
230 						u64 counters,
231 						bool defer)
232 {
233 	if (!counters)
234 		return;
235 
236 	atomic64_or(counters, &pmu->__reprogram_pmi);
237 	if (defer)
238 		kvm_make_request(KVM_REQ_PMU, pmu_to_vcpu(pmu));
239 	else
240 		kvm_pmu_handle_event(pmu_to_vcpu(pmu));
241 }
242 
243 static inline void kvm_pmu_request_counters_reprogram(struct kvm_pmu *pmu,
244 						      u64 counters)
245 {
246 	__kvm_pmu_reprogram_counters(pmu, counters, true);
247 }
248 
249 /*
250  * Check if a PMC is enabled by comparing it against global_ctrl bits.
251  *
252  * If the vPMU doesn't have global_ctrl MSR, all vPMCs are enabled.
253  */
254 static inline bool pmc_is_globally_enabled(struct kvm_pmc *pmc)
255 {
256 	struct kvm_pmu *pmu = pmc_to_pmu(pmc);
257 
258 	if (!kvm_pmu_has_perf_global_ctrl(pmu))
259 		return true;
260 
261 	return test_bit(pmc->idx, (unsigned long *)&pmu->global_ctrl);
262 }
263 
264 static inline bool kvm_pmu_is_fastpath_emulation_allowed(struct kvm_vcpu *vcpu)
265 {
266 	struct kvm_pmu *pmu = vcpu_to_pmu(vcpu);
267 
268 	return !kvm_vcpu_has_mediated_pmu(vcpu) ||
269 	       !bitmap_intersects(pmu->pmc_counting_instructions,
270 				  (unsigned long *)&pmu->global_ctrl,
271 				  X86_PMC_IDX_MAX);
272 }
273 
274 void kvm_pmu_deliver_pmi(struct kvm_vcpu *vcpu);
275 int kvm_pmu_rdpmc(struct kvm_vcpu *vcpu, unsigned pmc, u64 *data);
276 int kvm_pmu_check_rdpmc_early(struct kvm_vcpu *vcpu, unsigned int idx);
277 bool kvm_pmu_is_valid_msr(struct kvm_vcpu *vcpu, u32 msr);
278 int kvm_pmu_get_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info);
279 int kvm_pmu_set_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info);
280 void kvm_pmu_refresh(struct kvm_vcpu *vcpu);
281 void kvm_pmu_init(struct kvm_vcpu *vcpu);
282 void kvm_pmu_cleanup(struct kvm_vcpu *vcpu);
283 void kvm_pmu_destroy(struct kvm_vcpu *vcpu);
284 int kvm_vm_ioctl_set_pmu_event_filter(struct kvm *kvm, void __user *argp);
285 void kvm_pmu_instruction_retired(struct kvm_vcpu *vcpu);
286 void kvm_pmu_branch_retired(struct kvm_vcpu *vcpu);
287 void kvm_mediated_pmu_load(struct kvm_vcpu *vcpu);
288 void kvm_mediated_pmu_put(struct kvm_vcpu *vcpu);
289 
290 bool is_vmware_backdoor_pmc(u32 pmc_idx);
291 bool kvm_need_perf_global_ctrl_intercept(struct kvm_vcpu *vcpu);
292 bool kvm_need_rdpmc_intercept(struct kvm_vcpu *vcpu);
293 
294 extern struct kvm_pmu_ops intel_pmu_ops;
295 extern struct kvm_pmu_ops amd_pmu_ops;
296 #endif /* __KVM_X86_PMU_H */
297