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[J-linux.git] / arch / x86 / kvm / vmx / pmu_intel.c
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * KVM PMU support for Intel CPUs
4  *
5  * Copyright 2011 Red Hat, Inc. and/or its affiliates.
6  *
7  * Authors:
8  *   Avi Kivity   <[email protected]>
9  *   Gleb Natapov <[email protected]>
10  */
11 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
12
13 #include <linux/types.h>
14 #include <linux/kvm_host.h>
15 #include <linux/perf_event.h>
16 #include <asm/perf_event.h>
17 #include "x86.h"
18 #include "cpuid.h"
19 #include "lapic.h"
20 #include "nested.h"
21 #include "pmu.h"
22
23 /*
24  * Perf's "BASE" is wildly misleading, architectural PMUs use bits 31:16 of ECX
25  * to encode the "type" of counter to read, i.e. this is not a "base".  And to
26  * further confuse things, non-architectural PMUs use bit 31 as a flag for
27  * "fast" reads, whereas the "type" is an explicit value.
28  */
29 #define INTEL_RDPMC_GP          0
30 #define INTEL_RDPMC_FIXED       INTEL_PMC_FIXED_RDPMC_BASE
31
32 #define INTEL_RDPMC_TYPE_MASK   GENMASK(31, 16)
33 #define INTEL_RDPMC_INDEX_MASK  GENMASK(15, 0)
34
35 #define MSR_PMC_FULL_WIDTH_BIT      (MSR_IA32_PMC0 - MSR_IA32_PERFCTR0)
36
37 static void reprogram_fixed_counters(struct kvm_pmu *pmu, u64 data)
38 {
39         struct kvm_pmc *pmc;
40         u64 old_fixed_ctr_ctrl = pmu->fixed_ctr_ctrl;
41         int i;
42
43         pmu->fixed_ctr_ctrl = data;
44         for (i = 0; i < pmu->nr_arch_fixed_counters; i++) {
45                 u8 new_ctrl = fixed_ctrl_field(data, i);
46                 u8 old_ctrl = fixed_ctrl_field(old_fixed_ctr_ctrl, i);
47
48                 if (old_ctrl == new_ctrl)
49                         continue;
50
51                 pmc = get_fixed_pmc(pmu, MSR_CORE_PERF_FIXED_CTR0 + i);
52
53                 __set_bit(KVM_FIXED_PMC_BASE_IDX + i, pmu->pmc_in_use);
54                 kvm_pmu_request_counter_reprogram(pmc);
55         }
56 }
57
58 static struct kvm_pmc *intel_rdpmc_ecx_to_pmc(struct kvm_vcpu *vcpu,
59                                             unsigned int idx, u64 *mask)
60 {
61         unsigned int type = idx & INTEL_RDPMC_TYPE_MASK;
62         struct kvm_pmu *pmu = vcpu_to_pmu(vcpu);
63         struct kvm_pmc *counters;
64         unsigned int num_counters;
65         u64 bitmask;
66
67         /*
68          * The encoding of ECX for RDPMC is different for architectural versus
69          * non-architecturals PMUs (PMUs with version '0').  For architectural
70          * PMUs, bits 31:16 specify the PMC type and bits 15:0 specify the PMC
71          * index.  For non-architectural PMUs, bit 31 is a "fast" flag, and
72          * bits 30:0 specify the PMC index.
73          *
74          * Yell and reject attempts to read PMCs for a non-architectural PMU,
75          * as KVM doesn't support such PMUs.
76          */
77         if (WARN_ON_ONCE(!pmu->version))
78                 return NULL;
79
80         /*
81          * General Purpose (GP) PMCs are supported on all PMUs, and fixed PMCs
82          * are supported on all architectural PMUs, i.e. on all virtual PMUs
83          * supported by KVM.  Note, KVM only emulates fixed PMCs for PMU v2+,
84          * but the type itself is still valid, i.e. let RDPMC fail due to
85          * accessing a non-existent counter.  Reject attempts to read all other
86          * types, which are unknown/unsupported.
87          */
88         switch (type) {
89         case INTEL_RDPMC_FIXED:
90                 counters = pmu->fixed_counters;
91                 num_counters = pmu->nr_arch_fixed_counters;
92                 bitmask = pmu->counter_bitmask[KVM_PMC_FIXED];
93                 break;
94         case INTEL_RDPMC_GP:
95                 counters = pmu->gp_counters;
96                 num_counters = pmu->nr_arch_gp_counters;
97                 bitmask = pmu->counter_bitmask[KVM_PMC_GP];
98                 break;
99         default:
100                 return NULL;
101         }
102
103         idx &= INTEL_RDPMC_INDEX_MASK;
104         if (idx >= num_counters)
105                 return NULL;
106
107         *mask &= bitmask;
108         return &counters[array_index_nospec(idx, num_counters)];
109 }
110
111 static inline u64 vcpu_get_perf_capabilities(struct kvm_vcpu *vcpu)
112 {
113         if (!guest_cpuid_has(vcpu, X86_FEATURE_PDCM))
114                 return 0;
115
116         return vcpu->arch.perf_capabilities;
117 }
118
119 static inline bool fw_writes_is_enabled(struct kvm_vcpu *vcpu)
120 {
121         return (vcpu_get_perf_capabilities(vcpu) & PMU_CAP_FW_WRITES) != 0;
122 }
123
124 static inline struct kvm_pmc *get_fw_gp_pmc(struct kvm_pmu *pmu, u32 msr)
125 {
126         if (!fw_writes_is_enabled(pmu_to_vcpu(pmu)))
127                 return NULL;
128
129         return get_gp_pmc(pmu, msr, MSR_IA32_PMC0);
130 }
131
132 static bool intel_pmu_is_valid_lbr_msr(struct kvm_vcpu *vcpu, u32 index)
133 {
134         struct x86_pmu_lbr *records = vcpu_to_lbr_records(vcpu);
135         bool ret = false;
136
137         if (!intel_pmu_lbr_is_enabled(vcpu))
138                 return ret;
139
140         ret = (index == MSR_LBR_SELECT) || (index == MSR_LBR_TOS) ||
141                 (index >= records->from && index < records->from + records->nr) ||
142                 (index >= records->to && index < records->to + records->nr);
143
144         if (!ret && records->info)
145                 ret = (index >= records->info && index < records->info + records->nr);
146
147         return ret;
148 }
149
150 static bool intel_is_valid_msr(struct kvm_vcpu *vcpu, u32 msr)
151 {
152         struct kvm_pmu *pmu = vcpu_to_pmu(vcpu);
153         u64 perf_capabilities;
154         int ret;
155
156         switch (msr) {
157         case MSR_CORE_PERF_FIXED_CTR_CTRL:
158                 return kvm_pmu_has_perf_global_ctrl(pmu);
159         case MSR_IA32_PEBS_ENABLE:
160                 ret = vcpu_get_perf_capabilities(vcpu) & PERF_CAP_PEBS_FORMAT;
161                 break;
162         case MSR_IA32_DS_AREA:
163                 ret = guest_cpuid_has(vcpu, X86_FEATURE_DS);
164                 break;
165         case MSR_PEBS_DATA_CFG:
166                 perf_capabilities = vcpu_get_perf_capabilities(vcpu);
167                 ret = (perf_capabilities & PERF_CAP_PEBS_BASELINE) &&
168                         ((perf_capabilities & PERF_CAP_PEBS_FORMAT) > 3);
169                 break;
170         default:
171                 ret = get_gp_pmc(pmu, msr, MSR_IA32_PERFCTR0) ||
172                         get_gp_pmc(pmu, msr, MSR_P6_EVNTSEL0) ||
173                         get_fixed_pmc(pmu, msr) || get_fw_gp_pmc(pmu, msr) ||
174                         intel_pmu_is_valid_lbr_msr(vcpu, msr);
175                 break;
176         }
177
178         return ret;
179 }
180
181 static struct kvm_pmc *intel_msr_idx_to_pmc(struct kvm_vcpu *vcpu, u32 msr)
182 {
183         struct kvm_pmu *pmu = vcpu_to_pmu(vcpu);
184         struct kvm_pmc *pmc;
185
186         pmc = get_fixed_pmc(pmu, msr);
187         pmc = pmc ? pmc : get_gp_pmc(pmu, msr, MSR_P6_EVNTSEL0);
188         pmc = pmc ? pmc : get_gp_pmc(pmu, msr, MSR_IA32_PERFCTR0);
189
190         return pmc;
191 }
192
193 static inline void intel_pmu_release_guest_lbr_event(struct kvm_vcpu *vcpu)
194 {
195         struct lbr_desc *lbr_desc = vcpu_to_lbr_desc(vcpu);
196
197         if (lbr_desc->event) {
198                 perf_event_release_kernel(lbr_desc->event);
199                 lbr_desc->event = NULL;
200                 vcpu_to_pmu(vcpu)->event_count--;
201         }
202 }
203
204 int intel_pmu_create_guest_lbr_event(struct kvm_vcpu *vcpu)
205 {
206         struct lbr_desc *lbr_desc = vcpu_to_lbr_desc(vcpu);
207         struct kvm_pmu *pmu = vcpu_to_pmu(vcpu);
208         struct perf_event *event;
209
210         /*
211          * The perf_event_attr is constructed in the minimum efficient way:
212          * - set 'pinned = true' to make it task pinned so that if another
213          *   cpu pinned event reclaims LBR, the event->oncpu will be set to -1;
214          * - set '.exclude_host = true' to record guest branches behavior;
215          *
216          * - set '.config = INTEL_FIXED_VLBR_EVENT' to indicates host perf
217          *   schedule the event without a real HW counter but a fake one;
218          *   check is_guest_lbr_event() and __intel_get_event_constraints();
219          *
220          * - set 'sample_type = PERF_SAMPLE_BRANCH_STACK' and
221          *   'branch_sample_type = PERF_SAMPLE_BRANCH_CALL_STACK |
222          *   PERF_SAMPLE_BRANCH_USER' to configure it as a LBR callstack
223          *   event, which helps KVM to save/restore guest LBR records
224          *   during host context switches and reduces quite a lot overhead,
225          *   check branch_user_callstack() and intel_pmu_lbr_sched_task();
226          */
227         struct perf_event_attr attr = {
228                 .type = PERF_TYPE_RAW,
229                 .size = sizeof(attr),
230                 .config = INTEL_FIXED_VLBR_EVENT,
231                 .sample_type = PERF_SAMPLE_BRANCH_STACK,
232                 .pinned = true,
233                 .exclude_host = true,
234                 .branch_sample_type = PERF_SAMPLE_BRANCH_CALL_STACK |
235                                         PERF_SAMPLE_BRANCH_USER,
236         };
237
238         if (unlikely(lbr_desc->event)) {
239                 __set_bit(INTEL_PMC_IDX_FIXED_VLBR, pmu->pmc_in_use);
240                 return 0;
241         }
242
243         event = perf_event_create_kernel_counter(&attr, -1,
244                                                 current, NULL, NULL);
245         if (IS_ERR(event)) {
246                 pr_debug_ratelimited("%s: failed %ld\n",
247                                         __func__, PTR_ERR(event));
248                 return PTR_ERR(event);
249         }
250         lbr_desc->event = event;
251         pmu->event_count++;
252         __set_bit(INTEL_PMC_IDX_FIXED_VLBR, pmu->pmc_in_use);
253         return 0;
254 }
255
256 /*
257  * It's safe to access LBR msrs from guest when they have not
258  * been passthrough since the host would help restore or reset
259  * the LBR msrs records when the guest LBR event is scheduled in.
260  */
261 static bool intel_pmu_handle_lbr_msrs_access(struct kvm_vcpu *vcpu,
262                                      struct msr_data *msr_info, bool read)
263 {
264         struct lbr_desc *lbr_desc = vcpu_to_lbr_desc(vcpu);
265         u32 index = msr_info->index;
266
267         if (!intel_pmu_is_valid_lbr_msr(vcpu, index))
268                 return false;
269
270         if (!lbr_desc->event && intel_pmu_create_guest_lbr_event(vcpu) < 0)
271                 goto dummy;
272
273         /*
274          * Disable irq to ensure the LBR feature doesn't get reclaimed by the
275          * host at the time the value is read from the msr, and this avoids the
276          * host LBR value to be leaked to the guest. If LBR has been reclaimed,
277          * return 0 on guest reads.
278          */
279         local_irq_disable();
280         if (lbr_desc->event->state == PERF_EVENT_STATE_ACTIVE) {
281                 if (read)
282                         rdmsrl(index, msr_info->data);
283                 else
284                         wrmsrl(index, msr_info->data);
285                 __set_bit(INTEL_PMC_IDX_FIXED_VLBR, vcpu_to_pmu(vcpu)->pmc_in_use);
286                 local_irq_enable();
287                 return true;
288         }
289         clear_bit(INTEL_PMC_IDX_FIXED_VLBR, vcpu_to_pmu(vcpu)->pmc_in_use);
290         local_irq_enable();
291
292 dummy:
293         if (read)
294                 msr_info->data = 0;
295         return true;
296 }
297
298 static int intel_pmu_get_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
299 {
300         struct kvm_pmu *pmu = vcpu_to_pmu(vcpu);
301         struct kvm_pmc *pmc;
302         u32 msr = msr_info->index;
303
304         switch (msr) {
305         case MSR_CORE_PERF_FIXED_CTR_CTRL:
306                 msr_info->data = pmu->fixed_ctr_ctrl;
307                 break;
308         case MSR_IA32_PEBS_ENABLE:
309                 msr_info->data = pmu->pebs_enable;
310                 break;
311         case MSR_IA32_DS_AREA:
312                 msr_info->data = pmu->ds_area;
313                 break;
314         case MSR_PEBS_DATA_CFG:
315                 msr_info->data = pmu->pebs_data_cfg;
316                 break;
317         default:
318                 if ((pmc = get_gp_pmc(pmu, msr, MSR_IA32_PERFCTR0)) ||
319                     (pmc = get_gp_pmc(pmu, msr, MSR_IA32_PMC0))) {
320                         u64 val = pmc_read_counter(pmc);
321                         msr_info->data =
322                                 val & pmu->counter_bitmask[KVM_PMC_GP];
323                         break;
324                 } else if ((pmc = get_fixed_pmc(pmu, msr))) {
325                         u64 val = pmc_read_counter(pmc);
326                         msr_info->data =
327                                 val & pmu->counter_bitmask[KVM_PMC_FIXED];
328                         break;
329                 } else if ((pmc = get_gp_pmc(pmu, msr, MSR_P6_EVNTSEL0))) {
330                         msr_info->data = pmc->eventsel;
331                         break;
332                 } else if (intel_pmu_handle_lbr_msrs_access(vcpu, msr_info, true)) {
333                         break;
334                 }
335                 return 1;
336         }
337
338         return 0;
339 }
340
341 static int intel_pmu_set_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
342 {
343         struct kvm_pmu *pmu = vcpu_to_pmu(vcpu);
344         struct kvm_pmc *pmc;
345         u32 msr = msr_info->index;
346         u64 data = msr_info->data;
347         u64 reserved_bits, diff;
348
349         switch (msr) {
350         case MSR_CORE_PERF_FIXED_CTR_CTRL:
351                 if (data & pmu->fixed_ctr_ctrl_rsvd)
352                         return 1;
353
354                 if (pmu->fixed_ctr_ctrl != data)
355                         reprogram_fixed_counters(pmu, data);
356                 break;
357         case MSR_IA32_PEBS_ENABLE:
358                 if (data & pmu->pebs_enable_rsvd)
359                         return 1;
360
361                 if (pmu->pebs_enable != data) {
362                         diff = pmu->pebs_enable ^ data;
363                         pmu->pebs_enable = data;
364                         reprogram_counters(pmu, diff);
365                 }
366                 break;
367         case MSR_IA32_DS_AREA:
368                 if (is_noncanonical_msr_address(data, vcpu))
369                         return 1;
370
371                 pmu->ds_area = data;
372                 break;
373         case MSR_PEBS_DATA_CFG:
374                 if (data & pmu->pebs_data_cfg_rsvd)
375                         return 1;
376
377                 pmu->pebs_data_cfg = data;
378                 break;
379         default:
380                 if ((pmc = get_gp_pmc(pmu, msr, MSR_IA32_PERFCTR0)) ||
381                     (pmc = get_gp_pmc(pmu, msr, MSR_IA32_PMC0))) {
382                         if ((msr & MSR_PMC_FULL_WIDTH_BIT) &&
383                             (data & ~pmu->counter_bitmask[KVM_PMC_GP]))
384                                 return 1;
385
386                         if (!msr_info->host_initiated &&
387                             !(msr & MSR_PMC_FULL_WIDTH_BIT))
388                                 data = (s64)(s32)data;
389                         pmc_write_counter(pmc, data);
390                         break;
391                 } else if ((pmc = get_fixed_pmc(pmu, msr))) {
392                         pmc_write_counter(pmc, data);
393                         break;
394                 } else if ((pmc = get_gp_pmc(pmu, msr, MSR_P6_EVNTSEL0))) {
395                         reserved_bits = pmu->reserved_bits;
396                         if ((pmc->idx == 2) &&
397                             (pmu->raw_event_mask & HSW_IN_TX_CHECKPOINTED))
398                                 reserved_bits ^= HSW_IN_TX_CHECKPOINTED;
399                         if (data & reserved_bits)
400                                 return 1;
401
402                         if (data != pmc->eventsel) {
403                                 pmc->eventsel = data;
404                                 kvm_pmu_request_counter_reprogram(pmc);
405                         }
406                         break;
407                 } else if (intel_pmu_handle_lbr_msrs_access(vcpu, msr_info, false)) {
408                         break;
409                 }
410                 /* Not a known PMU MSR. */
411                 return 1;
412         }
413
414         return 0;
415 }
416
417 /*
418  * Map fixed counter events to architectural general purpose event encodings.
419  * Perf doesn't provide APIs to allow KVM to directly program a fixed counter,
420  * and so KVM instead programs the architectural event to effectively request
421  * the fixed counter.  Perf isn't guaranteed to use a fixed counter and may
422  * instead program the encoding into a general purpose counter, e.g. if a
423  * different perf_event is already utilizing the requested counter, but the end
424  * result is the same (ignoring the fact that using a general purpose counter
425  * will likely exacerbate counter contention).
426  *
427  * Forcibly inlined to allow asserting on @index at build time, and there should
428  * never be more than one user.
429  */
430 static __always_inline u64 intel_get_fixed_pmc_eventsel(unsigned int index)
431 {
432         const enum perf_hw_id fixed_pmc_perf_ids[] = {
433                 [0] = PERF_COUNT_HW_INSTRUCTIONS,
434                 [1] = PERF_COUNT_HW_CPU_CYCLES,
435                 [2] = PERF_COUNT_HW_REF_CPU_CYCLES,
436         };
437         u64 eventsel;
438
439         BUILD_BUG_ON(ARRAY_SIZE(fixed_pmc_perf_ids) != KVM_MAX_NR_INTEL_FIXED_COUTNERS);
440         BUILD_BUG_ON(index >= KVM_MAX_NR_INTEL_FIXED_COUTNERS);
441
442         /*
443          * Yell if perf reports support for a fixed counter but perf doesn't
444          * have a known encoding for the associated general purpose event.
445          */
446         eventsel = perf_get_hw_event_config(fixed_pmc_perf_ids[index]);
447         WARN_ON_ONCE(!eventsel && index < kvm_pmu_cap.num_counters_fixed);
448         return eventsel;
449 }
450
451 static void intel_pmu_enable_fixed_counter_bits(struct kvm_pmu *pmu, u64 bits)
452 {
453         int i;
454
455         for (i = 0; i < pmu->nr_arch_fixed_counters; i++)
456                 pmu->fixed_ctr_ctrl_rsvd &= ~intel_fixed_bits_by_idx(i, bits);
457 }
458
459 static void intel_pmu_refresh(struct kvm_vcpu *vcpu)
460 {
461         struct kvm_pmu *pmu = vcpu_to_pmu(vcpu);
462         struct lbr_desc *lbr_desc = vcpu_to_lbr_desc(vcpu);
463         struct kvm_cpuid_entry2 *entry;
464         union cpuid10_eax eax;
465         union cpuid10_edx edx;
466         u64 perf_capabilities;
467         u64 counter_rsvd;
468
469         memset(&lbr_desc->records, 0, sizeof(lbr_desc->records));
470
471         /*
472          * Setting passthrough of LBR MSRs is done only in the VM-Entry loop,
473          * and PMU refresh is disallowed after the vCPU has run, i.e. this code
474          * should never be reached while KVM is passing through MSRs.
475          */
476         if (KVM_BUG_ON(lbr_desc->msr_passthrough, vcpu->kvm))
477                 return;
478
479         entry = kvm_find_cpuid_entry(vcpu, 0xa);
480         if (!entry)
481                 return;
482
483         eax.full = entry->eax;
484         edx.full = entry->edx;
485
486         pmu->version = eax.split.version_id;
487         if (!pmu->version)
488                 return;
489
490         pmu->nr_arch_gp_counters = min_t(int, eax.split.num_counters,
491                                          kvm_pmu_cap.num_counters_gp);
492         eax.split.bit_width = min_t(int, eax.split.bit_width,
493                                     kvm_pmu_cap.bit_width_gp);
494         pmu->counter_bitmask[KVM_PMC_GP] = ((u64)1 << eax.split.bit_width) - 1;
495         eax.split.mask_length = min_t(int, eax.split.mask_length,
496                                       kvm_pmu_cap.events_mask_len);
497         pmu->available_event_types = ~entry->ebx &
498                                         ((1ull << eax.split.mask_length) - 1);
499
500         if (pmu->version == 1) {
501                 pmu->nr_arch_fixed_counters = 0;
502         } else {
503                 pmu->nr_arch_fixed_counters = min_t(int, edx.split.num_counters_fixed,
504                                                     kvm_pmu_cap.num_counters_fixed);
505                 edx.split.bit_width_fixed = min_t(int, edx.split.bit_width_fixed,
506                                                   kvm_pmu_cap.bit_width_fixed);
507                 pmu->counter_bitmask[KVM_PMC_FIXED] =
508                         ((u64)1 << edx.split.bit_width_fixed) - 1;
509         }
510
511         intel_pmu_enable_fixed_counter_bits(pmu, INTEL_FIXED_0_KERNEL |
512                                                  INTEL_FIXED_0_USER |
513                                                  INTEL_FIXED_0_ENABLE_PMI);
514
515         counter_rsvd = ~(((1ull << pmu->nr_arch_gp_counters) - 1) |
516                 (((1ull << pmu->nr_arch_fixed_counters) - 1) << KVM_FIXED_PMC_BASE_IDX));
517         pmu->global_ctrl_rsvd = counter_rsvd;
518
519         /*
520          * GLOBAL_STATUS and GLOBAL_OVF_CONTROL (a.k.a. GLOBAL_STATUS_RESET)
521          * share reserved bit definitions.  The kernel just happens to use
522          * OVF_CTRL for the names.
523          */
524         pmu->global_status_rsvd = pmu->global_ctrl_rsvd
525                         & ~(MSR_CORE_PERF_GLOBAL_OVF_CTRL_OVF_BUF |
526                             MSR_CORE_PERF_GLOBAL_OVF_CTRL_COND_CHGD);
527         if (vmx_pt_mode_is_host_guest())
528                 pmu->global_status_rsvd &=
529                                 ~MSR_CORE_PERF_GLOBAL_OVF_CTRL_TRACE_TOPA_PMI;
530
531         entry = kvm_find_cpuid_entry_index(vcpu, 7, 0);
532         if (entry &&
533             (boot_cpu_has(X86_FEATURE_HLE) || boot_cpu_has(X86_FEATURE_RTM)) &&
534             (entry->ebx & (X86_FEATURE_HLE|X86_FEATURE_RTM))) {
535                 pmu->reserved_bits ^= HSW_IN_TX;
536                 pmu->raw_event_mask |= (HSW_IN_TX|HSW_IN_TX_CHECKPOINTED);
537         }
538
539         bitmap_set(pmu->all_valid_pmc_idx,
540                 0, pmu->nr_arch_gp_counters);
541         bitmap_set(pmu->all_valid_pmc_idx,
542                 INTEL_PMC_MAX_GENERIC, pmu->nr_arch_fixed_counters);
543
544         perf_capabilities = vcpu_get_perf_capabilities(vcpu);
545         if (cpuid_model_is_consistent(vcpu) &&
546             (perf_capabilities & PMU_CAP_LBR_FMT))
547                 memcpy(&lbr_desc->records, &vmx_lbr_caps, sizeof(vmx_lbr_caps));
548         else
549                 lbr_desc->records.nr = 0;
550
551         if (lbr_desc->records.nr)
552                 bitmap_set(pmu->all_valid_pmc_idx, INTEL_PMC_IDX_FIXED_VLBR, 1);
553
554         if (perf_capabilities & PERF_CAP_PEBS_FORMAT) {
555                 if (perf_capabilities & PERF_CAP_PEBS_BASELINE) {
556                         pmu->pebs_enable_rsvd = counter_rsvd;
557                         pmu->reserved_bits &= ~ICL_EVENTSEL_ADAPTIVE;
558                         pmu->pebs_data_cfg_rsvd = ~0xff00000full;
559                         intel_pmu_enable_fixed_counter_bits(pmu, ICL_FIXED_0_ADAPTIVE);
560                 } else {
561                         pmu->pebs_enable_rsvd =
562                                 ~((1ull << pmu->nr_arch_gp_counters) - 1);
563                 }
564         }
565 }
566
567 static void intel_pmu_init(struct kvm_vcpu *vcpu)
568 {
569         int i;
570         struct kvm_pmu *pmu = vcpu_to_pmu(vcpu);
571         struct lbr_desc *lbr_desc = vcpu_to_lbr_desc(vcpu);
572
573         for (i = 0; i < KVM_MAX_NR_INTEL_GP_COUNTERS; i++) {
574                 pmu->gp_counters[i].type = KVM_PMC_GP;
575                 pmu->gp_counters[i].vcpu = vcpu;
576                 pmu->gp_counters[i].idx = i;
577                 pmu->gp_counters[i].current_config = 0;
578         }
579
580         for (i = 0; i < KVM_MAX_NR_INTEL_FIXED_COUTNERS; i++) {
581                 pmu->fixed_counters[i].type = KVM_PMC_FIXED;
582                 pmu->fixed_counters[i].vcpu = vcpu;
583                 pmu->fixed_counters[i].idx = i + KVM_FIXED_PMC_BASE_IDX;
584                 pmu->fixed_counters[i].current_config = 0;
585                 pmu->fixed_counters[i].eventsel = intel_get_fixed_pmc_eventsel(i);
586         }
587
588         lbr_desc->records.nr = 0;
589         lbr_desc->event = NULL;
590         lbr_desc->msr_passthrough = false;
591 }
592
593 static void intel_pmu_reset(struct kvm_vcpu *vcpu)
594 {
595         intel_pmu_release_guest_lbr_event(vcpu);
596 }
597
598 /*
599  * Emulate LBR_On_PMI behavior for 1 < pmu.version < 4.
600  *
601  * If Freeze_LBR_On_PMI = 1, the LBR is frozen on PMI and
602  * the KVM emulates to clear the LBR bit (bit 0) in IA32_DEBUGCTL.
603  *
604  * Guest needs to re-enable LBR to resume branches recording.
605  */
606 static void intel_pmu_legacy_freezing_lbrs_on_pmi(struct kvm_vcpu *vcpu)
607 {
608         u64 data = vmcs_read64(GUEST_IA32_DEBUGCTL);
609
610         if (data & DEBUGCTLMSR_FREEZE_LBRS_ON_PMI) {
611                 data &= ~DEBUGCTLMSR_LBR;
612                 vmcs_write64(GUEST_IA32_DEBUGCTL, data);
613         }
614 }
615
616 static void intel_pmu_deliver_pmi(struct kvm_vcpu *vcpu)
617 {
618         u8 version = vcpu_to_pmu(vcpu)->version;
619
620         if (!intel_pmu_lbr_is_enabled(vcpu))
621                 return;
622
623         if (version > 1 && version < 4)
624                 intel_pmu_legacy_freezing_lbrs_on_pmi(vcpu);
625 }
626
627 static void vmx_update_intercept_for_lbr_msrs(struct kvm_vcpu *vcpu, bool set)
628 {
629         struct x86_pmu_lbr *lbr = vcpu_to_lbr_records(vcpu);
630         int i;
631
632         for (i = 0; i < lbr->nr; i++) {
633                 vmx_set_intercept_for_msr(vcpu, lbr->from + i, MSR_TYPE_RW, set);
634                 vmx_set_intercept_for_msr(vcpu, lbr->to + i, MSR_TYPE_RW, set);
635                 if (lbr->info)
636                         vmx_set_intercept_for_msr(vcpu, lbr->info + i, MSR_TYPE_RW, set);
637         }
638
639         vmx_set_intercept_for_msr(vcpu, MSR_LBR_SELECT, MSR_TYPE_RW, set);
640         vmx_set_intercept_for_msr(vcpu, MSR_LBR_TOS, MSR_TYPE_RW, set);
641 }
642
643 static inline void vmx_disable_lbr_msrs_passthrough(struct kvm_vcpu *vcpu)
644 {
645         struct lbr_desc *lbr_desc = vcpu_to_lbr_desc(vcpu);
646
647         if (!lbr_desc->msr_passthrough)
648                 return;
649
650         vmx_update_intercept_for_lbr_msrs(vcpu, true);
651         lbr_desc->msr_passthrough = false;
652 }
653
654 static inline void vmx_enable_lbr_msrs_passthrough(struct kvm_vcpu *vcpu)
655 {
656         struct lbr_desc *lbr_desc = vcpu_to_lbr_desc(vcpu);
657
658         if (lbr_desc->msr_passthrough)
659                 return;
660
661         vmx_update_intercept_for_lbr_msrs(vcpu, false);
662         lbr_desc->msr_passthrough = true;
663 }
664
665 /*
666  * Higher priority host perf events (e.g. cpu pinned) could reclaim the
667  * pmu resources (e.g. LBR) that were assigned to the guest. This is
668  * usually done via ipi calls (more details in perf_install_in_context).
669  *
670  * Before entering the non-root mode (with irq disabled here), double
671  * confirm that the pmu features enabled to the guest are not reclaimed
672  * by higher priority host events. Otherwise, disallow vcpu's access to
673  * the reclaimed features.
674  */
675 void vmx_passthrough_lbr_msrs(struct kvm_vcpu *vcpu)
676 {
677         struct kvm_pmu *pmu = vcpu_to_pmu(vcpu);
678         struct lbr_desc *lbr_desc = vcpu_to_lbr_desc(vcpu);
679
680         if (!lbr_desc->event) {
681                 vmx_disable_lbr_msrs_passthrough(vcpu);
682                 if (vmcs_read64(GUEST_IA32_DEBUGCTL) & DEBUGCTLMSR_LBR)
683                         goto warn;
684                 if (test_bit(INTEL_PMC_IDX_FIXED_VLBR, pmu->pmc_in_use))
685                         goto warn;
686                 return;
687         }
688
689         if (lbr_desc->event->state < PERF_EVENT_STATE_ACTIVE) {
690                 vmx_disable_lbr_msrs_passthrough(vcpu);
691                 __clear_bit(INTEL_PMC_IDX_FIXED_VLBR, pmu->pmc_in_use);
692                 goto warn;
693         } else
694                 vmx_enable_lbr_msrs_passthrough(vcpu);
695
696         return;
697
698 warn:
699         pr_warn_ratelimited("vcpu-%d: fail to passthrough LBR.\n", vcpu->vcpu_id);
700 }
701
702 static void intel_pmu_cleanup(struct kvm_vcpu *vcpu)
703 {
704         if (!(vmcs_read64(GUEST_IA32_DEBUGCTL) & DEBUGCTLMSR_LBR))
705                 intel_pmu_release_guest_lbr_event(vcpu);
706 }
707
708 void intel_pmu_cross_mapped_check(struct kvm_pmu *pmu)
709 {
710         struct kvm_pmc *pmc = NULL;
711         int bit, hw_idx;
712
713         kvm_for_each_pmc(pmu, pmc, bit, (unsigned long *)&pmu->global_ctrl) {
714                 if (!pmc_speculative_in_use(pmc) ||
715                     !pmc_is_globally_enabled(pmc) || !pmc->perf_event)
716                         continue;
717
718                 /*
719                  * A negative index indicates the event isn't mapped to a
720                  * physical counter in the host, e.g. due to contention.
721                  */
722                 hw_idx = pmc->perf_event->hw.idx;
723                 if (hw_idx != pmc->idx && hw_idx > -1)
724                         pmu->host_cross_mapped_mask |= BIT_ULL(hw_idx);
725         }
726 }
727
728 struct kvm_pmu_ops intel_pmu_ops __initdata = {
729         .rdpmc_ecx_to_pmc = intel_rdpmc_ecx_to_pmc,
730         .msr_idx_to_pmc = intel_msr_idx_to_pmc,
731         .is_valid_msr = intel_is_valid_msr,
732         .get_msr = intel_pmu_get_msr,
733         .set_msr = intel_pmu_set_msr,
734         .refresh = intel_pmu_refresh,
735         .init = intel_pmu_init,
736         .reset = intel_pmu_reset,
737         .deliver_pmi = intel_pmu_deliver_pmi,
738         .cleanup = intel_pmu_cleanup,
739         .EVENTSEL_EVENT = ARCH_PERFMON_EVENTSEL_EVENT,
740         .MAX_NR_GP_COUNTERS = KVM_MAX_NR_INTEL_GP_COUNTERS,
741         .MIN_NR_GP_COUNTERS = 1,
742 };
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