xref: /openbmc/linux/drivers/perf/arm_pmuv3.c (revision cabce92d)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * ARMv8 PMUv3 Performance Events handling code.
4  *
5  * Copyright (C) 2012 ARM Limited
6  * Author: Will Deacon <will.deacon@arm.com>
7  *
8  * This code is based heavily on the ARMv7 perf event code.
9  */
10 
11 #include <asm/irq_regs.h>
12 #include <asm/perf_event.h>
13 #include <asm/virt.h>
14 
15 #include <clocksource/arm_arch_timer.h>
16 
17 #include <linux/acpi.h>
18 #include <linux/clocksource.h>
19 #include <linux/of.h>
20 #include <linux/perf/arm_pmu.h>
21 #include <linux/perf/arm_pmuv3.h>
22 #include <linux/platform_device.h>
23 #include <linux/sched_clock.h>
24 #include <linux/smp.h>
25 #include <linux/nmi.h>
26 
27 #include <asm/arm_pmuv3.h>
28 
29 /* ARMv8 Cortex-A53 specific event types. */
30 #define ARMV8_A53_PERFCTR_PREF_LINEFILL				0xC2
31 
32 /* ARMv8 Cavium ThunderX specific event types. */
33 #define ARMV8_THUNDER_PERFCTR_L1D_CACHE_MISS_ST			0xE9
34 #define ARMV8_THUNDER_PERFCTR_L1D_CACHE_PREF_ACCESS		0xEA
35 #define ARMV8_THUNDER_PERFCTR_L1D_CACHE_PREF_MISS		0xEB
36 #define ARMV8_THUNDER_PERFCTR_L1I_CACHE_PREF_ACCESS		0xEC
37 #define ARMV8_THUNDER_PERFCTR_L1I_CACHE_PREF_MISS		0xED
38 
39 /*
40  * ARMv8 Architectural defined events, not all of these may
41  * be supported on any given implementation. Unsupported events will
42  * be disabled at run-time based on the PMCEID registers.
43  */
44 static const unsigned armv8_pmuv3_perf_map[PERF_COUNT_HW_MAX] = {
45 	PERF_MAP_ALL_UNSUPPORTED,
46 	[PERF_COUNT_HW_CPU_CYCLES]		= ARMV8_PMUV3_PERFCTR_CPU_CYCLES,
47 	[PERF_COUNT_HW_INSTRUCTIONS]		= ARMV8_PMUV3_PERFCTR_INST_RETIRED,
48 	[PERF_COUNT_HW_CACHE_REFERENCES]	= ARMV8_PMUV3_PERFCTR_L1D_CACHE,
49 	[PERF_COUNT_HW_CACHE_MISSES]		= ARMV8_PMUV3_PERFCTR_L1D_CACHE_REFILL,
50 	[PERF_COUNT_HW_BRANCH_MISSES]		= ARMV8_PMUV3_PERFCTR_BR_MIS_PRED,
51 	[PERF_COUNT_HW_BUS_CYCLES]		= ARMV8_PMUV3_PERFCTR_BUS_CYCLES,
52 	[PERF_COUNT_HW_STALLED_CYCLES_FRONTEND]	= ARMV8_PMUV3_PERFCTR_STALL_FRONTEND,
53 	[PERF_COUNT_HW_STALLED_CYCLES_BACKEND]	= ARMV8_PMUV3_PERFCTR_STALL_BACKEND,
54 };
55 
56 static const unsigned armv8_pmuv3_perf_cache_map[PERF_COUNT_HW_CACHE_MAX]
57 						[PERF_COUNT_HW_CACHE_OP_MAX]
58 						[PERF_COUNT_HW_CACHE_RESULT_MAX] = {
59 	PERF_CACHE_MAP_ALL_UNSUPPORTED,
60 
61 	[C(L1D)][C(OP_READ)][C(RESULT_ACCESS)]	= ARMV8_PMUV3_PERFCTR_L1D_CACHE,
62 	[C(L1D)][C(OP_READ)][C(RESULT_MISS)]	= ARMV8_PMUV3_PERFCTR_L1D_CACHE_REFILL,
63 
64 	[C(L1I)][C(OP_READ)][C(RESULT_ACCESS)]	= ARMV8_PMUV3_PERFCTR_L1I_CACHE,
65 	[C(L1I)][C(OP_READ)][C(RESULT_MISS)]	= ARMV8_PMUV3_PERFCTR_L1I_CACHE_REFILL,
66 
67 	[C(DTLB)][C(OP_READ)][C(RESULT_MISS)]	= ARMV8_PMUV3_PERFCTR_L1D_TLB_REFILL,
68 	[C(DTLB)][C(OP_READ)][C(RESULT_ACCESS)]	= ARMV8_PMUV3_PERFCTR_L1D_TLB,
69 
70 	[C(ITLB)][C(OP_READ)][C(RESULT_MISS)]	= ARMV8_PMUV3_PERFCTR_L1I_TLB_REFILL,
71 	[C(ITLB)][C(OP_READ)][C(RESULT_ACCESS)]	= ARMV8_PMUV3_PERFCTR_L1I_TLB,
72 
73 	[C(LL)][C(OP_READ)][C(RESULT_MISS)]	= ARMV8_PMUV3_PERFCTR_LL_CACHE_MISS_RD,
74 	[C(LL)][C(OP_READ)][C(RESULT_ACCESS)]	= ARMV8_PMUV3_PERFCTR_LL_CACHE_RD,
75 
76 	[C(BPU)][C(OP_READ)][C(RESULT_ACCESS)]	= ARMV8_PMUV3_PERFCTR_BR_PRED,
77 	[C(BPU)][C(OP_READ)][C(RESULT_MISS)]	= ARMV8_PMUV3_PERFCTR_BR_MIS_PRED,
78 };
79 
80 static const unsigned armv8_a53_perf_cache_map[PERF_COUNT_HW_CACHE_MAX]
81 					      [PERF_COUNT_HW_CACHE_OP_MAX]
82 					      [PERF_COUNT_HW_CACHE_RESULT_MAX] = {
83 	PERF_CACHE_MAP_ALL_UNSUPPORTED,
84 
85 	[C(L1D)][C(OP_PREFETCH)][C(RESULT_MISS)] = ARMV8_A53_PERFCTR_PREF_LINEFILL,
86 
87 	[C(NODE)][C(OP_READ)][C(RESULT_ACCESS)]	= ARMV8_IMPDEF_PERFCTR_BUS_ACCESS_RD,
88 	[C(NODE)][C(OP_WRITE)][C(RESULT_ACCESS)] = ARMV8_IMPDEF_PERFCTR_BUS_ACCESS_WR,
89 };
90 
91 static const unsigned armv8_a57_perf_cache_map[PERF_COUNT_HW_CACHE_MAX]
92 					      [PERF_COUNT_HW_CACHE_OP_MAX]
93 					      [PERF_COUNT_HW_CACHE_RESULT_MAX] = {
94 	PERF_CACHE_MAP_ALL_UNSUPPORTED,
95 
96 	[C(L1D)][C(OP_READ)][C(RESULT_ACCESS)]	= ARMV8_IMPDEF_PERFCTR_L1D_CACHE_RD,
97 	[C(L1D)][C(OP_READ)][C(RESULT_MISS)]	= ARMV8_IMPDEF_PERFCTR_L1D_CACHE_REFILL_RD,
98 	[C(L1D)][C(OP_WRITE)][C(RESULT_ACCESS)]	= ARMV8_IMPDEF_PERFCTR_L1D_CACHE_WR,
99 	[C(L1D)][C(OP_WRITE)][C(RESULT_MISS)]	= ARMV8_IMPDEF_PERFCTR_L1D_CACHE_REFILL_WR,
100 
101 	[C(DTLB)][C(OP_READ)][C(RESULT_MISS)]	= ARMV8_IMPDEF_PERFCTR_L1D_TLB_REFILL_RD,
102 	[C(DTLB)][C(OP_WRITE)][C(RESULT_MISS)]	= ARMV8_IMPDEF_PERFCTR_L1D_TLB_REFILL_WR,
103 
104 	[C(NODE)][C(OP_READ)][C(RESULT_ACCESS)]	= ARMV8_IMPDEF_PERFCTR_BUS_ACCESS_RD,
105 	[C(NODE)][C(OP_WRITE)][C(RESULT_ACCESS)] = ARMV8_IMPDEF_PERFCTR_BUS_ACCESS_WR,
106 };
107 
108 static const unsigned armv8_a73_perf_cache_map[PERF_COUNT_HW_CACHE_MAX]
109 					      [PERF_COUNT_HW_CACHE_OP_MAX]
110 					      [PERF_COUNT_HW_CACHE_RESULT_MAX] = {
111 	PERF_CACHE_MAP_ALL_UNSUPPORTED,
112 
113 	[C(L1D)][C(OP_READ)][C(RESULT_ACCESS)]	= ARMV8_IMPDEF_PERFCTR_L1D_CACHE_RD,
114 	[C(L1D)][C(OP_WRITE)][C(RESULT_ACCESS)]	= ARMV8_IMPDEF_PERFCTR_L1D_CACHE_WR,
115 };
116 
117 static const unsigned armv8_thunder_perf_cache_map[PERF_COUNT_HW_CACHE_MAX]
118 						   [PERF_COUNT_HW_CACHE_OP_MAX]
119 						   [PERF_COUNT_HW_CACHE_RESULT_MAX] = {
120 	PERF_CACHE_MAP_ALL_UNSUPPORTED,
121 
122 	[C(L1D)][C(OP_READ)][C(RESULT_ACCESS)]	= ARMV8_IMPDEF_PERFCTR_L1D_CACHE_RD,
123 	[C(L1D)][C(OP_READ)][C(RESULT_MISS)]	= ARMV8_IMPDEF_PERFCTR_L1D_CACHE_REFILL_RD,
124 	[C(L1D)][C(OP_WRITE)][C(RESULT_ACCESS)]	= ARMV8_IMPDEF_PERFCTR_L1D_CACHE_WR,
125 	[C(L1D)][C(OP_WRITE)][C(RESULT_MISS)]	= ARMV8_THUNDER_PERFCTR_L1D_CACHE_MISS_ST,
126 	[C(L1D)][C(OP_PREFETCH)][C(RESULT_ACCESS)] = ARMV8_THUNDER_PERFCTR_L1D_CACHE_PREF_ACCESS,
127 	[C(L1D)][C(OP_PREFETCH)][C(RESULT_MISS)] = ARMV8_THUNDER_PERFCTR_L1D_CACHE_PREF_MISS,
128 
129 	[C(L1I)][C(OP_PREFETCH)][C(RESULT_ACCESS)] = ARMV8_THUNDER_PERFCTR_L1I_CACHE_PREF_ACCESS,
130 	[C(L1I)][C(OP_PREFETCH)][C(RESULT_MISS)] = ARMV8_THUNDER_PERFCTR_L1I_CACHE_PREF_MISS,
131 
132 	[C(DTLB)][C(OP_READ)][C(RESULT_ACCESS)]	= ARMV8_IMPDEF_PERFCTR_L1D_TLB_RD,
133 	[C(DTLB)][C(OP_READ)][C(RESULT_MISS)]	= ARMV8_IMPDEF_PERFCTR_L1D_TLB_REFILL_RD,
134 	[C(DTLB)][C(OP_WRITE)][C(RESULT_ACCESS)] = ARMV8_IMPDEF_PERFCTR_L1D_TLB_WR,
135 	[C(DTLB)][C(OP_WRITE)][C(RESULT_MISS)]	= ARMV8_IMPDEF_PERFCTR_L1D_TLB_REFILL_WR,
136 };
137 
138 static const unsigned armv8_vulcan_perf_cache_map[PERF_COUNT_HW_CACHE_MAX]
139 					      [PERF_COUNT_HW_CACHE_OP_MAX]
140 					      [PERF_COUNT_HW_CACHE_RESULT_MAX] = {
141 	PERF_CACHE_MAP_ALL_UNSUPPORTED,
142 
143 	[C(L1D)][C(OP_READ)][C(RESULT_ACCESS)]	= ARMV8_IMPDEF_PERFCTR_L1D_CACHE_RD,
144 	[C(L1D)][C(OP_READ)][C(RESULT_MISS)]	= ARMV8_IMPDEF_PERFCTR_L1D_CACHE_REFILL_RD,
145 	[C(L1D)][C(OP_WRITE)][C(RESULT_ACCESS)]	= ARMV8_IMPDEF_PERFCTR_L1D_CACHE_WR,
146 	[C(L1D)][C(OP_WRITE)][C(RESULT_MISS)]	= ARMV8_IMPDEF_PERFCTR_L1D_CACHE_REFILL_WR,
147 
148 	[C(DTLB)][C(OP_READ)][C(RESULT_ACCESS)]	= ARMV8_IMPDEF_PERFCTR_L1D_TLB_RD,
149 	[C(DTLB)][C(OP_WRITE)][C(RESULT_ACCESS)] = ARMV8_IMPDEF_PERFCTR_L1D_TLB_WR,
150 	[C(DTLB)][C(OP_READ)][C(RESULT_MISS)]	= ARMV8_IMPDEF_PERFCTR_L1D_TLB_REFILL_RD,
151 	[C(DTLB)][C(OP_WRITE)][C(RESULT_MISS)]	= ARMV8_IMPDEF_PERFCTR_L1D_TLB_REFILL_WR,
152 
153 	[C(NODE)][C(OP_READ)][C(RESULT_ACCESS)]	= ARMV8_IMPDEF_PERFCTR_BUS_ACCESS_RD,
154 	[C(NODE)][C(OP_WRITE)][C(RESULT_ACCESS)] = ARMV8_IMPDEF_PERFCTR_BUS_ACCESS_WR,
155 };
156 
157 static ssize_t
158 armv8pmu_events_sysfs_show(struct device *dev,
159 			   struct device_attribute *attr, char *page)
160 {
161 	struct perf_pmu_events_attr *pmu_attr;
162 
163 	pmu_attr = container_of(attr, struct perf_pmu_events_attr, attr);
164 
165 	return sprintf(page, "event=0x%04llx\n", pmu_attr->id);
166 }
167 
168 #define ARMV8_EVENT_ATTR(name, config)						\
169 	PMU_EVENT_ATTR_ID(name, armv8pmu_events_sysfs_show, config)
170 
171 static struct attribute *armv8_pmuv3_event_attrs[] = {
172 	ARMV8_EVENT_ATTR(sw_incr, ARMV8_PMUV3_PERFCTR_SW_INCR),
173 	ARMV8_EVENT_ATTR(l1i_cache_refill, ARMV8_PMUV3_PERFCTR_L1I_CACHE_REFILL),
174 	ARMV8_EVENT_ATTR(l1i_tlb_refill, ARMV8_PMUV3_PERFCTR_L1I_TLB_REFILL),
175 	ARMV8_EVENT_ATTR(l1d_cache_refill, ARMV8_PMUV3_PERFCTR_L1D_CACHE_REFILL),
176 	ARMV8_EVENT_ATTR(l1d_cache, ARMV8_PMUV3_PERFCTR_L1D_CACHE),
177 	ARMV8_EVENT_ATTR(l1d_tlb_refill, ARMV8_PMUV3_PERFCTR_L1D_TLB_REFILL),
178 	ARMV8_EVENT_ATTR(ld_retired, ARMV8_PMUV3_PERFCTR_LD_RETIRED),
179 	ARMV8_EVENT_ATTR(st_retired, ARMV8_PMUV3_PERFCTR_ST_RETIRED),
180 	ARMV8_EVENT_ATTR(inst_retired, ARMV8_PMUV3_PERFCTR_INST_RETIRED),
181 	ARMV8_EVENT_ATTR(exc_taken, ARMV8_PMUV3_PERFCTR_EXC_TAKEN),
182 	ARMV8_EVENT_ATTR(exc_return, ARMV8_PMUV3_PERFCTR_EXC_RETURN),
183 	ARMV8_EVENT_ATTR(cid_write_retired, ARMV8_PMUV3_PERFCTR_CID_WRITE_RETIRED),
184 	ARMV8_EVENT_ATTR(pc_write_retired, ARMV8_PMUV3_PERFCTR_PC_WRITE_RETIRED),
185 	ARMV8_EVENT_ATTR(br_immed_retired, ARMV8_PMUV3_PERFCTR_BR_IMMED_RETIRED),
186 	ARMV8_EVENT_ATTR(br_return_retired, ARMV8_PMUV3_PERFCTR_BR_RETURN_RETIRED),
187 	ARMV8_EVENT_ATTR(unaligned_ldst_retired, ARMV8_PMUV3_PERFCTR_UNALIGNED_LDST_RETIRED),
188 	ARMV8_EVENT_ATTR(br_mis_pred, ARMV8_PMUV3_PERFCTR_BR_MIS_PRED),
189 	ARMV8_EVENT_ATTR(cpu_cycles, ARMV8_PMUV3_PERFCTR_CPU_CYCLES),
190 	ARMV8_EVENT_ATTR(br_pred, ARMV8_PMUV3_PERFCTR_BR_PRED),
191 	ARMV8_EVENT_ATTR(mem_access, ARMV8_PMUV3_PERFCTR_MEM_ACCESS),
192 	ARMV8_EVENT_ATTR(l1i_cache, ARMV8_PMUV3_PERFCTR_L1I_CACHE),
193 	ARMV8_EVENT_ATTR(l1d_cache_wb, ARMV8_PMUV3_PERFCTR_L1D_CACHE_WB),
194 	ARMV8_EVENT_ATTR(l2d_cache, ARMV8_PMUV3_PERFCTR_L2D_CACHE),
195 	ARMV8_EVENT_ATTR(l2d_cache_refill, ARMV8_PMUV3_PERFCTR_L2D_CACHE_REFILL),
196 	ARMV8_EVENT_ATTR(l2d_cache_wb, ARMV8_PMUV3_PERFCTR_L2D_CACHE_WB),
197 	ARMV8_EVENT_ATTR(bus_access, ARMV8_PMUV3_PERFCTR_BUS_ACCESS),
198 	ARMV8_EVENT_ATTR(memory_error, ARMV8_PMUV3_PERFCTR_MEMORY_ERROR),
199 	ARMV8_EVENT_ATTR(inst_spec, ARMV8_PMUV3_PERFCTR_INST_SPEC),
200 	ARMV8_EVENT_ATTR(ttbr_write_retired, ARMV8_PMUV3_PERFCTR_TTBR_WRITE_RETIRED),
201 	ARMV8_EVENT_ATTR(bus_cycles, ARMV8_PMUV3_PERFCTR_BUS_CYCLES),
202 	/* Don't expose the chain event in /sys, since it's useless in isolation */
203 	ARMV8_EVENT_ATTR(l1d_cache_allocate, ARMV8_PMUV3_PERFCTR_L1D_CACHE_ALLOCATE),
204 	ARMV8_EVENT_ATTR(l2d_cache_allocate, ARMV8_PMUV3_PERFCTR_L2D_CACHE_ALLOCATE),
205 	ARMV8_EVENT_ATTR(br_retired, ARMV8_PMUV3_PERFCTR_BR_RETIRED),
206 	ARMV8_EVENT_ATTR(br_mis_pred_retired, ARMV8_PMUV3_PERFCTR_BR_MIS_PRED_RETIRED),
207 	ARMV8_EVENT_ATTR(stall_frontend, ARMV8_PMUV3_PERFCTR_STALL_FRONTEND),
208 	ARMV8_EVENT_ATTR(stall_backend, ARMV8_PMUV3_PERFCTR_STALL_BACKEND),
209 	ARMV8_EVENT_ATTR(l1d_tlb, ARMV8_PMUV3_PERFCTR_L1D_TLB),
210 	ARMV8_EVENT_ATTR(l1i_tlb, ARMV8_PMUV3_PERFCTR_L1I_TLB),
211 	ARMV8_EVENT_ATTR(l2i_cache, ARMV8_PMUV3_PERFCTR_L2I_CACHE),
212 	ARMV8_EVENT_ATTR(l2i_cache_refill, ARMV8_PMUV3_PERFCTR_L2I_CACHE_REFILL),
213 	ARMV8_EVENT_ATTR(l3d_cache_allocate, ARMV8_PMUV3_PERFCTR_L3D_CACHE_ALLOCATE),
214 	ARMV8_EVENT_ATTR(l3d_cache_refill, ARMV8_PMUV3_PERFCTR_L3D_CACHE_REFILL),
215 	ARMV8_EVENT_ATTR(l3d_cache, ARMV8_PMUV3_PERFCTR_L3D_CACHE),
216 	ARMV8_EVENT_ATTR(l3d_cache_wb, ARMV8_PMUV3_PERFCTR_L3D_CACHE_WB),
217 	ARMV8_EVENT_ATTR(l2d_tlb_refill, ARMV8_PMUV3_PERFCTR_L2D_TLB_REFILL),
218 	ARMV8_EVENT_ATTR(l2i_tlb_refill, ARMV8_PMUV3_PERFCTR_L2I_TLB_REFILL),
219 	ARMV8_EVENT_ATTR(l2d_tlb, ARMV8_PMUV3_PERFCTR_L2D_TLB),
220 	ARMV8_EVENT_ATTR(l2i_tlb, ARMV8_PMUV3_PERFCTR_L2I_TLB),
221 	ARMV8_EVENT_ATTR(remote_access, ARMV8_PMUV3_PERFCTR_REMOTE_ACCESS),
222 	ARMV8_EVENT_ATTR(ll_cache, ARMV8_PMUV3_PERFCTR_LL_CACHE),
223 	ARMV8_EVENT_ATTR(ll_cache_miss, ARMV8_PMUV3_PERFCTR_LL_CACHE_MISS),
224 	ARMV8_EVENT_ATTR(dtlb_walk, ARMV8_PMUV3_PERFCTR_DTLB_WALK),
225 	ARMV8_EVENT_ATTR(itlb_walk, ARMV8_PMUV3_PERFCTR_ITLB_WALK),
226 	ARMV8_EVENT_ATTR(ll_cache_rd, ARMV8_PMUV3_PERFCTR_LL_CACHE_RD),
227 	ARMV8_EVENT_ATTR(ll_cache_miss_rd, ARMV8_PMUV3_PERFCTR_LL_CACHE_MISS_RD),
228 	ARMV8_EVENT_ATTR(remote_access_rd, ARMV8_PMUV3_PERFCTR_REMOTE_ACCESS_RD),
229 	ARMV8_EVENT_ATTR(l1d_cache_lmiss_rd, ARMV8_PMUV3_PERFCTR_L1D_CACHE_LMISS_RD),
230 	ARMV8_EVENT_ATTR(op_retired, ARMV8_PMUV3_PERFCTR_OP_RETIRED),
231 	ARMV8_EVENT_ATTR(op_spec, ARMV8_PMUV3_PERFCTR_OP_SPEC),
232 	ARMV8_EVENT_ATTR(stall, ARMV8_PMUV3_PERFCTR_STALL),
233 	ARMV8_EVENT_ATTR(stall_slot_backend, ARMV8_PMUV3_PERFCTR_STALL_SLOT_BACKEND),
234 	ARMV8_EVENT_ATTR(stall_slot_frontend, ARMV8_PMUV3_PERFCTR_STALL_SLOT_FRONTEND),
235 	ARMV8_EVENT_ATTR(stall_slot, ARMV8_PMUV3_PERFCTR_STALL_SLOT),
236 	ARMV8_EVENT_ATTR(sample_pop, ARMV8_SPE_PERFCTR_SAMPLE_POP),
237 	ARMV8_EVENT_ATTR(sample_feed, ARMV8_SPE_PERFCTR_SAMPLE_FEED),
238 	ARMV8_EVENT_ATTR(sample_filtrate, ARMV8_SPE_PERFCTR_SAMPLE_FILTRATE),
239 	ARMV8_EVENT_ATTR(sample_collision, ARMV8_SPE_PERFCTR_SAMPLE_COLLISION),
240 	ARMV8_EVENT_ATTR(cnt_cycles, ARMV8_AMU_PERFCTR_CNT_CYCLES),
241 	ARMV8_EVENT_ATTR(stall_backend_mem, ARMV8_AMU_PERFCTR_STALL_BACKEND_MEM),
242 	ARMV8_EVENT_ATTR(l1i_cache_lmiss, ARMV8_PMUV3_PERFCTR_L1I_CACHE_LMISS),
243 	ARMV8_EVENT_ATTR(l2d_cache_lmiss_rd, ARMV8_PMUV3_PERFCTR_L2D_CACHE_LMISS_RD),
244 	ARMV8_EVENT_ATTR(l2i_cache_lmiss, ARMV8_PMUV3_PERFCTR_L2I_CACHE_LMISS),
245 	ARMV8_EVENT_ATTR(l3d_cache_lmiss_rd, ARMV8_PMUV3_PERFCTR_L3D_CACHE_LMISS_RD),
246 	ARMV8_EVENT_ATTR(trb_wrap, ARMV8_PMUV3_PERFCTR_TRB_WRAP),
247 	ARMV8_EVENT_ATTR(trb_trig, ARMV8_PMUV3_PERFCTR_TRB_TRIG),
248 	ARMV8_EVENT_ATTR(trcextout0, ARMV8_PMUV3_PERFCTR_TRCEXTOUT0),
249 	ARMV8_EVENT_ATTR(trcextout1, ARMV8_PMUV3_PERFCTR_TRCEXTOUT1),
250 	ARMV8_EVENT_ATTR(trcextout2, ARMV8_PMUV3_PERFCTR_TRCEXTOUT2),
251 	ARMV8_EVENT_ATTR(trcextout3, ARMV8_PMUV3_PERFCTR_TRCEXTOUT3),
252 	ARMV8_EVENT_ATTR(cti_trigout4, ARMV8_PMUV3_PERFCTR_CTI_TRIGOUT4),
253 	ARMV8_EVENT_ATTR(cti_trigout5, ARMV8_PMUV3_PERFCTR_CTI_TRIGOUT5),
254 	ARMV8_EVENT_ATTR(cti_trigout6, ARMV8_PMUV3_PERFCTR_CTI_TRIGOUT6),
255 	ARMV8_EVENT_ATTR(cti_trigout7, ARMV8_PMUV3_PERFCTR_CTI_TRIGOUT7),
256 	ARMV8_EVENT_ATTR(ldst_align_lat, ARMV8_PMUV3_PERFCTR_LDST_ALIGN_LAT),
257 	ARMV8_EVENT_ATTR(ld_align_lat, ARMV8_PMUV3_PERFCTR_LD_ALIGN_LAT),
258 	ARMV8_EVENT_ATTR(st_align_lat, ARMV8_PMUV3_PERFCTR_ST_ALIGN_LAT),
259 	ARMV8_EVENT_ATTR(mem_access_checked, ARMV8_MTE_PERFCTR_MEM_ACCESS_CHECKED),
260 	ARMV8_EVENT_ATTR(mem_access_checked_rd, ARMV8_MTE_PERFCTR_MEM_ACCESS_CHECKED_RD),
261 	ARMV8_EVENT_ATTR(mem_access_checked_wr, ARMV8_MTE_PERFCTR_MEM_ACCESS_CHECKED_WR),
262 	NULL,
263 };
264 
265 static umode_t
266 armv8pmu_event_attr_is_visible(struct kobject *kobj,
267 			       struct attribute *attr, int unused)
268 {
269 	struct device *dev = kobj_to_dev(kobj);
270 	struct pmu *pmu = dev_get_drvdata(dev);
271 	struct arm_pmu *cpu_pmu = container_of(pmu, struct arm_pmu, pmu);
272 	struct perf_pmu_events_attr *pmu_attr;
273 
274 	pmu_attr = container_of(attr, struct perf_pmu_events_attr, attr.attr);
275 
276 	if (pmu_attr->id < ARMV8_PMUV3_MAX_COMMON_EVENTS &&
277 	    test_bit(pmu_attr->id, cpu_pmu->pmceid_bitmap))
278 		return attr->mode;
279 
280 	if (pmu_attr->id >= ARMV8_PMUV3_EXT_COMMON_EVENT_BASE) {
281 		u64 id = pmu_attr->id - ARMV8_PMUV3_EXT_COMMON_EVENT_BASE;
282 
283 		if (id < ARMV8_PMUV3_MAX_COMMON_EVENTS &&
284 		    test_bit(id, cpu_pmu->pmceid_ext_bitmap))
285 			return attr->mode;
286 	}
287 
288 	return 0;
289 }
290 
291 static const struct attribute_group armv8_pmuv3_events_attr_group = {
292 	.name = "events",
293 	.attrs = armv8_pmuv3_event_attrs,
294 	.is_visible = armv8pmu_event_attr_is_visible,
295 };
296 
297 PMU_FORMAT_ATTR(event, "config:0-15");
298 PMU_FORMAT_ATTR(long, "config1:0");
299 PMU_FORMAT_ATTR(rdpmc, "config1:1");
300 
301 static int sysctl_perf_user_access __read_mostly;
302 
303 static inline bool armv8pmu_event_is_64bit(struct perf_event *event)
304 {
305 	return event->attr.config1 & 0x1;
306 }
307 
308 static inline bool armv8pmu_event_want_user_access(struct perf_event *event)
309 {
310 	return event->attr.config1 & 0x2;
311 }
312 
313 static struct attribute *armv8_pmuv3_format_attrs[] = {
314 	&format_attr_event.attr,
315 	&format_attr_long.attr,
316 	&format_attr_rdpmc.attr,
317 	NULL,
318 };
319 
320 static const struct attribute_group armv8_pmuv3_format_attr_group = {
321 	.name = "format",
322 	.attrs = armv8_pmuv3_format_attrs,
323 };
324 
325 static ssize_t slots_show(struct device *dev, struct device_attribute *attr,
326 			  char *page)
327 {
328 	struct pmu *pmu = dev_get_drvdata(dev);
329 	struct arm_pmu *cpu_pmu = container_of(pmu, struct arm_pmu, pmu);
330 	u32 slots = cpu_pmu->reg_pmmir & ARMV8_PMU_SLOTS_MASK;
331 
332 	return sysfs_emit(page, "0x%08x\n", slots);
333 }
334 
335 static DEVICE_ATTR_RO(slots);
336 
337 static ssize_t bus_slots_show(struct device *dev, struct device_attribute *attr,
338 			      char *page)
339 {
340 	struct pmu *pmu = dev_get_drvdata(dev);
341 	struct arm_pmu *cpu_pmu = container_of(pmu, struct arm_pmu, pmu);
342 	u32 bus_slots = (cpu_pmu->reg_pmmir >> ARMV8_PMU_BUS_SLOTS_SHIFT)
343 			& ARMV8_PMU_BUS_SLOTS_MASK;
344 
345 	return sysfs_emit(page, "0x%08x\n", bus_slots);
346 }
347 
348 static DEVICE_ATTR_RO(bus_slots);
349 
350 static ssize_t bus_width_show(struct device *dev, struct device_attribute *attr,
351 			      char *page)
352 {
353 	struct pmu *pmu = dev_get_drvdata(dev);
354 	struct arm_pmu *cpu_pmu = container_of(pmu, struct arm_pmu, pmu);
355 	u32 bus_width = (cpu_pmu->reg_pmmir >> ARMV8_PMU_BUS_WIDTH_SHIFT)
356 			& ARMV8_PMU_BUS_WIDTH_MASK;
357 	u32 val = 0;
358 
359 	/* Encoded as Log2(number of bytes), plus one */
360 	if (bus_width > 2 && bus_width < 13)
361 		val = 1 << (bus_width - 1);
362 
363 	return sysfs_emit(page, "0x%08x\n", val);
364 }
365 
366 static DEVICE_ATTR_RO(bus_width);
367 
368 static struct attribute *armv8_pmuv3_caps_attrs[] = {
369 	&dev_attr_slots.attr,
370 	&dev_attr_bus_slots.attr,
371 	&dev_attr_bus_width.attr,
372 	NULL,
373 };
374 
375 static const struct attribute_group armv8_pmuv3_caps_attr_group = {
376 	.name = "caps",
377 	.attrs = armv8_pmuv3_caps_attrs,
378 };
379 
380 /*
381  * Perf Events' indices
382  */
383 #define	ARMV8_IDX_CYCLE_COUNTER	0
384 #define	ARMV8_IDX_COUNTER0	1
385 #define	ARMV8_IDX_CYCLE_COUNTER_USER	32
386 
387 /*
388  * We unconditionally enable ARMv8.5-PMU long event counter support
389  * (64-bit events) where supported. Indicate if this arm_pmu has long
390  * event counter support.
391  *
392  * On AArch32, long counters make no sense (you can't access the top
393  * bits), so we only enable this on AArch64.
394  */
395 static bool armv8pmu_has_long_event(struct arm_pmu *cpu_pmu)
396 {
397 	return (IS_ENABLED(CONFIG_ARM64) && is_pmuv3p5(cpu_pmu->pmuver));
398 }
399 
400 static inline bool armv8pmu_event_has_user_read(struct perf_event *event)
401 {
402 	return event->hw.flags & PERF_EVENT_FLAG_USER_READ_CNT;
403 }
404 
405 /*
406  * We must chain two programmable counters for 64 bit events,
407  * except when we have allocated the 64bit cycle counter (for CPU
408  * cycles event) or when user space counter access is enabled.
409  */
410 static inline bool armv8pmu_event_is_chained(struct perf_event *event)
411 {
412 	int idx = event->hw.idx;
413 	struct arm_pmu *cpu_pmu = to_arm_pmu(event->pmu);
414 
415 	return !armv8pmu_event_has_user_read(event) &&
416 	       armv8pmu_event_is_64bit(event) &&
417 	       !armv8pmu_has_long_event(cpu_pmu) &&
418 	       (idx != ARMV8_IDX_CYCLE_COUNTER);
419 }
420 
421 /*
422  * ARMv8 low level PMU access
423  */
424 
425 /*
426  * Perf Event to low level counters mapping
427  */
428 #define	ARMV8_IDX_TO_COUNTER(x)	\
429 	(((x) - ARMV8_IDX_COUNTER0) & ARMV8_PMU_COUNTER_MASK)
430 
431 static inline u32 armv8pmu_pmcr_read(void)
432 {
433 	return read_pmcr();
434 }
435 
436 static inline void armv8pmu_pmcr_write(u32 val)
437 {
438 	val &= ARMV8_PMU_PMCR_MASK;
439 	isb();
440 	write_pmcr(val);
441 }
442 
443 static inline int armv8pmu_has_overflowed(u32 pmovsr)
444 {
445 	return pmovsr & ARMV8_PMU_OVERFLOWED_MASK;
446 }
447 
448 static inline int armv8pmu_counter_has_overflowed(u32 pmnc, int idx)
449 {
450 	return pmnc & BIT(ARMV8_IDX_TO_COUNTER(idx));
451 }
452 
453 static inline u64 armv8pmu_read_evcntr(int idx)
454 {
455 	u32 counter = ARMV8_IDX_TO_COUNTER(idx);
456 
457 	return read_pmevcntrn(counter);
458 }
459 
460 static inline u64 armv8pmu_read_hw_counter(struct perf_event *event)
461 {
462 	int idx = event->hw.idx;
463 	u64 val = armv8pmu_read_evcntr(idx);
464 
465 	if (armv8pmu_event_is_chained(event))
466 		val = (val << 32) | armv8pmu_read_evcntr(idx - 1);
467 	return val;
468 }
469 
470 /*
471  * The cycle counter is always a 64-bit counter. When ARMV8_PMU_PMCR_LP
472  * is set the event counters also become 64-bit counters. Unless the
473  * user has requested a long counter (attr.config1) then we want to
474  * interrupt upon 32-bit overflow - we achieve this by applying a bias.
475  */
476 static bool armv8pmu_event_needs_bias(struct perf_event *event)
477 {
478 	struct arm_pmu *cpu_pmu = to_arm_pmu(event->pmu);
479 	struct hw_perf_event *hwc = &event->hw;
480 	int idx = hwc->idx;
481 
482 	if (armv8pmu_event_is_64bit(event))
483 		return false;
484 
485 	if (armv8pmu_has_long_event(cpu_pmu) ||
486 	    idx == ARMV8_IDX_CYCLE_COUNTER)
487 		return true;
488 
489 	return false;
490 }
491 
492 static u64 armv8pmu_bias_long_counter(struct perf_event *event, u64 value)
493 {
494 	if (armv8pmu_event_needs_bias(event))
495 		value |= GENMASK_ULL(63, 32);
496 
497 	return value;
498 }
499 
500 static u64 armv8pmu_unbias_long_counter(struct perf_event *event, u64 value)
501 {
502 	if (armv8pmu_event_needs_bias(event))
503 		value &= ~GENMASK_ULL(63, 32);
504 
505 	return value;
506 }
507 
508 static u64 armv8pmu_read_counter(struct perf_event *event)
509 {
510 	struct hw_perf_event *hwc = &event->hw;
511 	int idx = hwc->idx;
512 	u64 value;
513 
514 	if (idx == ARMV8_IDX_CYCLE_COUNTER)
515 		value = read_pmccntr();
516 	else
517 		value = armv8pmu_read_hw_counter(event);
518 
519 	return  armv8pmu_unbias_long_counter(event, value);
520 }
521 
522 static inline void armv8pmu_write_evcntr(int idx, u64 value)
523 {
524 	u32 counter = ARMV8_IDX_TO_COUNTER(idx);
525 
526 	write_pmevcntrn(counter, value);
527 }
528 
529 static inline void armv8pmu_write_hw_counter(struct perf_event *event,
530 					     u64 value)
531 {
532 	int idx = event->hw.idx;
533 
534 	if (armv8pmu_event_is_chained(event)) {
535 		armv8pmu_write_evcntr(idx, upper_32_bits(value));
536 		armv8pmu_write_evcntr(idx - 1, lower_32_bits(value));
537 	} else {
538 		armv8pmu_write_evcntr(idx, value);
539 	}
540 }
541 
542 static void armv8pmu_write_counter(struct perf_event *event, u64 value)
543 {
544 	struct hw_perf_event *hwc = &event->hw;
545 	int idx = hwc->idx;
546 
547 	value = armv8pmu_bias_long_counter(event, value);
548 
549 	if (idx == ARMV8_IDX_CYCLE_COUNTER)
550 		write_pmccntr(value);
551 	else
552 		armv8pmu_write_hw_counter(event, value);
553 }
554 
555 static inline void armv8pmu_write_evtype(int idx, u32 val)
556 {
557 	u32 counter = ARMV8_IDX_TO_COUNTER(idx);
558 
559 	val &= ARMV8_PMU_EVTYPE_MASK;
560 	write_pmevtypern(counter, val);
561 }
562 
563 static inline void armv8pmu_write_event_type(struct perf_event *event)
564 {
565 	struct hw_perf_event *hwc = &event->hw;
566 	int idx = hwc->idx;
567 
568 	/*
569 	 * For chained events, the low counter is programmed to count
570 	 * the event of interest and the high counter is programmed
571 	 * with CHAIN event code with filters set to count at all ELs.
572 	 */
573 	if (armv8pmu_event_is_chained(event)) {
574 		u32 chain_evt = ARMV8_PMUV3_PERFCTR_CHAIN |
575 				ARMV8_PMU_INCLUDE_EL2;
576 
577 		armv8pmu_write_evtype(idx - 1, hwc->config_base);
578 		armv8pmu_write_evtype(idx, chain_evt);
579 	} else {
580 		if (idx == ARMV8_IDX_CYCLE_COUNTER)
581 			write_pmccfiltr(hwc->config_base);
582 		else
583 			armv8pmu_write_evtype(idx, hwc->config_base);
584 	}
585 }
586 
587 static u32 armv8pmu_event_cnten_mask(struct perf_event *event)
588 {
589 	int counter = ARMV8_IDX_TO_COUNTER(event->hw.idx);
590 	u32 mask = BIT(counter);
591 
592 	if (armv8pmu_event_is_chained(event))
593 		mask |= BIT(counter - 1);
594 	return mask;
595 }
596 
597 static inline void armv8pmu_enable_counter(u32 mask)
598 {
599 	/*
600 	 * Make sure event configuration register writes are visible before we
601 	 * enable the counter.
602 	 * */
603 	isb();
604 	write_pmcntenset(mask);
605 }
606 
607 static inline void armv8pmu_enable_event_counter(struct perf_event *event)
608 {
609 	struct perf_event_attr *attr = &event->attr;
610 	u32 mask = armv8pmu_event_cnten_mask(event);
611 
612 	kvm_set_pmu_events(mask, attr);
613 
614 	/* We rely on the hypervisor switch code to enable guest counters */
615 	if (!kvm_pmu_counter_deferred(attr))
616 		armv8pmu_enable_counter(mask);
617 }
618 
619 static inline void armv8pmu_disable_counter(u32 mask)
620 {
621 	write_pmcntenclr(mask);
622 	/*
623 	 * Make sure the effects of disabling the counter are visible before we
624 	 * start configuring the event.
625 	 */
626 	isb();
627 }
628 
629 static inline void armv8pmu_disable_event_counter(struct perf_event *event)
630 {
631 	struct perf_event_attr *attr = &event->attr;
632 	u32 mask = armv8pmu_event_cnten_mask(event);
633 
634 	kvm_clr_pmu_events(mask);
635 
636 	/* We rely on the hypervisor switch code to disable guest counters */
637 	if (!kvm_pmu_counter_deferred(attr))
638 		armv8pmu_disable_counter(mask);
639 }
640 
641 static inline void armv8pmu_enable_intens(u32 mask)
642 {
643 	write_pmintenset(mask);
644 }
645 
646 static inline void armv8pmu_enable_event_irq(struct perf_event *event)
647 {
648 	u32 counter = ARMV8_IDX_TO_COUNTER(event->hw.idx);
649 	armv8pmu_enable_intens(BIT(counter));
650 }
651 
652 static inline void armv8pmu_disable_intens(u32 mask)
653 {
654 	write_pmintenclr(mask);
655 	isb();
656 	/* Clear the overflow flag in case an interrupt is pending. */
657 	write_pmovsclr(mask);
658 	isb();
659 }
660 
661 static inline void armv8pmu_disable_event_irq(struct perf_event *event)
662 {
663 	u32 counter = ARMV8_IDX_TO_COUNTER(event->hw.idx);
664 	armv8pmu_disable_intens(BIT(counter));
665 }
666 
667 static inline u32 armv8pmu_getreset_flags(void)
668 {
669 	u32 value;
670 
671 	/* Read */
672 	value = read_pmovsclr();
673 
674 	/* Write to clear flags */
675 	value &= ARMV8_PMU_OVSR_MASK;
676 	write_pmovsclr(value);
677 
678 	return value;
679 }
680 
681 static void update_pmuserenr(u64 val)
682 {
683 	lockdep_assert_irqs_disabled();
684 
685 	/*
686 	 * The current PMUSERENR_EL0 value might be the value for the guest.
687 	 * If that's the case, have KVM keep tracking of the register value
688 	 * for the host EL0 so that KVM can restore it before returning to
689 	 * the host EL0. Otherwise, update the register now.
690 	 */
691 	if (kvm_set_pmuserenr(val))
692 		return;
693 
694 	write_pmuserenr(val);
695 }
696 
697 static void armv8pmu_disable_user_access(void)
698 {
699 	update_pmuserenr(0);
700 }
701 
702 static void armv8pmu_enable_user_access(struct arm_pmu *cpu_pmu)
703 {
704 	int i;
705 	struct pmu_hw_events *cpuc = this_cpu_ptr(cpu_pmu->hw_events);
706 
707 	/* Clear any unused counters to avoid leaking their contents */
708 	for_each_clear_bit(i, cpuc->used_mask, cpu_pmu->num_events) {
709 		if (i == ARMV8_IDX_CYCLE_COUNTER)
710 			write_pmccntr(0);
711 		else
712 			armv8pmu_write_evcntr(i, 0);
713 	}
714 
715 	update_pmuserenr(ARMV8_PMU_USERENR_ER | ARMV8_PMU_USERENR_CR);
716 }
717 
718 static void armv8pmu_enable_event(struct perf_event *event)
719 {
720 	/*
721 	 * Enable counter and interrupt, and set the counter to count
722 	 * the event that we're interested in.
723 	 */
724 
725 	/*
726 	 * Disable counter
727 	 */
728 	armv8pmu_disable_event_counter(event);
729 
730 	/*
731 	 * Set event.
732 	 */
733 	armv8pmu_write_event_type(event);
734 
735 	/*
736 	 * Enable interrupt for this counter
737 	 */
738 	armv8pmu_enable_event_irq(event);
739 
740 	/*
741 	 * Enable counter
742 	 */
743 	armv8pmu_enable_event_counter(event);
744 }
745 
746 static void armv8pmu_disable_event(struct perf_event *event)
747 {
748 	/*
749 	 * Disable counter
750 	 */
751 	armv8pmu_disable_event_counter(event);
752 
753 	/*
754 	 * Disable interrupt for this counter
755 	 */
756 	armv8pmu_disable_event_irq(event);
757 }
758 
759 static void armv8pmu_start(struct arm_pmu *cpu_pmu)
760 {
761 	struct perf_event_context *ctx;
762 	int nr_user = 0;
763 
764 	ctx = perf_cpu_task_ctx();
765 	if (ctx)
766 		nr_user = ctx->nr_user;
767 
768 	if (sysctl_perf_user_access && nr_user)
769 		armv8pmu_enable_user_access(cpu_pmu);
770 	else
771 		armv8pmu_disable_user_access();
772 
773 	/* Enable all counters */
774 	armv8pmu_pmcr_write(armv8pmu_pmcr_read() | ARMV8_PMU_PMCR_E);
775 }
776 
777 static void armv8pmu_stop(struct arm_pmu *cpu_pmu)
778 {
779 	/* Disable all counters */
780 	armv8pmu_pmcr_write(armv8pmu_pmcr_read() & ~ARMV8_PMU_PMCR_E);
781 }
782 
783 static irqreturn_t armv8pmu_handle_irq(struct arm_pmu *cpu_pmu)
784 {
785 	u32 pmovsr;
786 	struct perf_sample_data data;
787 	struct pmu_hw_events *cpuc = this_cpu_ptr(cpu_pmu->hw_events);
788 	struct pt_regs *regs;
789 	int idx;
790 
791 	/*
792 	 * Get and reset the IRQ flags
793 	 */
794 	pmovsr = armv8pmu_getreset_flags();
795 
796 	/*
797 	 * Did an overflow occur?
798 	 */
799 	if (!armv8pmu_has_overflowed(pmovsr))
800 		return IRQ_NONE;
801 
802 	/*
803 	 * Handle the counter(s) overflow(s)
804 	 */
805 	regs = get_irq_regs();
806 
807 	/*
808 	 * Stop the PMU while processing the counter overflows
809 	 * to prevent skews in group events.
810 	 */
811 	armv8pmu_stop(cpu_pmu);
812 	for (idx = 0; idx < cpu_pmu->num_events; ++idx) {
813 		struct perf_event *event = cpuc->events[idx];
814 		struct hw_perf_event *hwc;
815 
816 		/* Ignore if we don't have an event. */
817 		if (!event)
818 			continue;
819 
820 		/*
821 		 * We have a single interrupt for all counters. Check that
822 		 * each counter has overflowed before we process it.
823 		 */
824 		if (!armv8pmu_counter_has_overflowed(pmovsr, idx))
825 			continue;
826 
827 		hwc = &event->hw;
828 		armpmu_event_update(event);
829 		perf_sample_data_init(&data, 0, hwc->last_period);
830 		if (!armpmu_event_set_period(event))
831 			continue;
832 
833 		/*
834 		 * Perf event overflow will queue the processing of the event as
835 		 * an irq_work which will be taken care of in the handling of
836 		 * IPI_IRQ_WORK.
837 		 */
838 		if (perf_event_overflow(event, &data, regs))
839 			cpu_pmu->disable(event);
840 	}
841 	armv8pmu_start(cpu_pmu);
842 
843 	return IRQ_HANDLED;
844 }
845 
846 static int armv8pmu_get_single_idx(struct pmu_hw_events *cpuc,
847 				    struct arm_pmu *cpu_pmu)
848 {
849 	int idx;
850 
851 	for (idx = ARMV8_IDX_COUNTER0; idx < cpu_pmu->num_events; idx++) {
852 		if (!test_and_set_bit(idx, cpuc->used_mask))
853 			return idx;
854 	}
855 	return -EAGAIN;
856 }
857 
858 static int armv8pmu_get_chain_idx(struct pmu_hw_events *cpuc,
859 				   struct arm_pmu *cpu_pmu)
860 {
861 	int idx;
862 
863 	/*
864 	 * Chaining requires two consecutive event counters, where
865 	 * the lower idx must be even.
866 	 */
867 	for (idx = ARMV8_IDX_COUNTER0 + 1; idx < cpu_pmu->num_events; idx += 2) {
868 		if (!test_and_set_bit(idx, cpuc->used_mask)) {
869 			/* Check if the preceding even counter is available */
870 			if (!test_and_set_bit(idx - 1, cpuc->used_mask))
871 				return idx;
872 			/* Release the Odd counter */
873 			clear_bit(idx, cpuc->used_mask);
874 		}
875 	}
876 	return -EAGAIN;
877 }
878 
879 static int armv8pmu_get_event_idx(struct pmu_hw_events *cpuc,
880 				  struct perf_event *event)
881 {
882 	struct arm_pmu *cpu_pmu = to_arm_pmu(event->pmu);
883 	struct hw_perf_event *hwc = &event->hw;
884 	unsigned long evtype = hwc->config_base & ARMV8_PMU_EVTYPE_EVENT;
885 
886 	/* Always prefer to place a cycle counter into the cycle counter. */
887 	if (evtype == ARMV8_PMUV3_PERFCTR_CPU_CYCLES) {
888 		if (!test_and_set_bit(ARMV8_IDX_CYCLE_COUNTER, cpuc->used_mask))
889 			return ARMV8_IDX_CYCLE_COUNTER;
890 		else if (armv8pmu_event_is_64bit(event) &&
891 			   armv8pmu_event_want_user_access(event) &&
892 			   !armv8pmu_has_long_event(cpu_pmu))
893 				return -EAGAIN;
894 	}
895 
896 	/*
897 	 * Otherwise use events counters
898 	 */
899 	if (armv8pmu_event_is_chained(event))
900 		return	armv8pmu_get_chain_idx(cpuc, cpu_pmu);
901 	else
902 		return armv8pmu_get_single_idx(cpuc, cpu_pmu);
903 }
904 
905 static void armv8pmu_clear_event_idx(struct pmu_hw_events *cpuc,
906 				     struct perf_event *event)
907 {
908 	int idx = event->hw.idx;
909 
910 	clear_bit(idx, cpuc->used_mask);
911 	if (armv8pmu_event_is_chained(event))
912 		clear_bit(idx - 1, cpuc->used_mask);
913 }
914 
915 static int armv8pmu_user_event_idx(struct perf_event *event)
916 {
917 	if (!sysctl_perf_user_access || !armv8pmu_event_has_user_read(event))
918 		return 0;
919 
920 	/*
921 	 * We remap the cycle counter index to 32 to
922 	 * match the offset applied to the rest of
923 	 * the counter indices.
924 	 */
925 	if (event->hw.idx == ARMV8_IDX_CYCLE_COUNTER)
926 		return ARMV8_IDX_CYCLE_COUNTER_USER;
927 
928 	return event->hw.idx;
929 }
930 
931 /*
932  * Add an event filter to a given event.
933  */
934 static int armv8pmu_set_event_filter(struct hw_perf_event *event,
935 				     struct perf_event_attr *attr)
936 {
937 	unsigned long config_base = 0;
938 
939 	if (attr->exclude_idle)
940 		return -EPERM;
941 
942 	/*
943 	 * If we're running in hyp mode, then we *are* the hypervisor.
944 	 * Therefore we ignore exclude_hv in this configuration, since
945 	 * there's no hypervisor to sample anyway. This is consistent
946 	 * with other architectures (x86 and Power).
947 	 */
948 	if (is_kernel_in_hyp_mode()) {
949 		if (!attr->exclude_kernel && !attr->exclude_host)
950 			config_base |= ARMV8_PMU_INCLUDE_EL2;
951 		if (attr->exclude_guest)
952 			config_base |= ARMV8_PMU_EXCLUDE_EL1;
953 		if (attr->exclude_host)
954 			config_base |= ARMV8_PMU_EXCLUDE_EL0;
955 	} else {
956 		if (!attr->exclude_hv && !attr->exclude_host)
957 			config_base |= ARMV8_PMU_INCLUDE_EL2;
958 	}
959 
960 	/*
961 	 * Filter out !VHE kernels and guest kernels
962 	 */
963 	if (attr->exclude_kernel)
964 		config_base |= ARMV8_PMU_EXCLUDE_EL1;
965 
966 	if (attr->exclude_user)
967 		config_base |= ARMV8_PMU_EXCLUDE_EL0;
968 
969 	/*
970 	 * Install the filter into config_base as this is used to
971 	 * construct the event type.
972 	 */
973 	event->config_base = config_base;
974 
975 	return 0;
976 }
977 
978 static void armv8pmu_reset(void *info)
979 {
980 	struct arm_pmu *cpu_pmu = (struct arm_pmu *)info;
981 	u32 pmcr;
982 
983 	/* The counter and interrupt enable registers are unknown at reset. */
984 	armv8pmu_disable_counter(U32_MAX);
985 	armv8pmu_disable_intens(U32_MAX);
986 
987 	/* Clear the counters we flip at guest entry/exit */
988 	kvm_clr_pmu_events(U32_MAX);
989 
990 	/*
991 	 * Initialize & Reset PMNC. Request overflow interrupt for
992 	 * 64 bit cycle counter but cheat in armv8pmu_write_counter().
993 	 */
994 	pmcr = ARMV8_PMU_PMCR_P | ARMV8_PMU_PMCR_C | ARMV8_PMU_PMCR_LC;
995 
996 	/* Enable long event counter support where available */
997 	if (armv8pmu_has_long_event(cpu_pmu))
998 		pmcr |= ARMV8_PMU_PMCR_LP;
999 
1000 	armv8pmu_pmcr_write(pmcr);
1001 }
1002 
1003 static int __armv8_pmuv3_map_event_id(struct arm_pmu *armpmu,
1004 				      struct perf_event *event)
1005 {
1006 	if (event->attr.type == PERF_TYPE_HARDWARE &&
1007 	    event->attr.config == PERF_COUNT_HW_BRANCH_INSTRUCTIONS) {
1008 
1009 		if (test_bit(ARMV8_PMUV3_PERFCTR_PC_WRITE_RETIRED,
1010 			     armpmu->pmceid_bitmap))
1011 			return ARMV8_PMUV3_PERFCTR_PC_WRITE_RETIRED;
1012 
1013 		if (test_bit(ARMV8_PMUV3_PERFCTR_BR_RETIRED,
1014 			     armpmu->pmceid_bitmap))
1015 			return ARMV8_PMUV3_PERFCTR_BR_RETIRED;
1016 
1017 		return HW_OP_UNSUPPORTED;
1018 	}
1019 
1020 	return armpmu_map_event(event, &armv8_pmuv3_perf_map,
1021 				&armv8_pmuv3_perf_cache_map,
1022 				ARMV8_PMU_EVTYPE_EVENT);
1023 }
1024 
1025 static int __armv8_pmuv3_map_event(struct perf_event *event,
1026 				   const unsigned (*extra_event_map)
1027 						  [PERF_COUNT_HW_MAX],
1028 				   const unsigned (*extra_cache_map)
1029 						  [PERF_COUNT_HW_CACHE_MAX]
1030 						  [PERF_COUNT_HW_CACHE_OP_MAX]
1031 						  [PERF_COUNT_HW_CACHE_RESULT_MAX])
1032 {
1033 	int hw_event_id;
1034 	struct arm_pmu *armpmu = to_arm_pmu(event->pmu);
1035 
1036 	hw_event_id = __armv8_pmuv3_map_event_id(armpmu, event);
1037 
1038 	/*
1039 	 * CHAIN events only work when paired with an adjacent counter, and it
1040 	 * never makes sense for a user to open one in isolation, as they'll be
1041 	 * rotated arbitrarily.
1042 	 */
1043 	if (hw_event_id == ARMV8_PMUV3_PERFCTR_CHAIN)
1044 		return -EINVAL;
1045 
1046 	if (armv8pmu_event_is_64bit(event))
1047 		event->hw.flags |= ARMPMU_EVT_64BIT;
1048 
1049 	/*
1050 	 * User events must be allocated into a single counter, and so
1051 	 * must not be chained.
1052 	 *
1053 	 * Most 64-bit events require long counter support, but 64-bit
1054 	 * CPU_CYCLES events can be placed into the dedicated cycle
1055 	 * counter when this is free.
1056 	 */
1057 	if (armv8pmu_event_want_user_access(event)) {
1058 		if (!(event->attach_state & PERF_ATTACH_TASK))
1059 			return -EINVAL;
1060 		if (armv8pmu_event_is_64bit(event) &&
1061 		    (hw_event_id != ARMV8_PMUV3_PERFCTR_CPU_CYCLES) &&
1062 		    !armv8pmu_has_long_event(armpmu))
1063 			return -EOPNOTSUPP;
1064 
1065 		event->hw.flags |= PERF_EVENT_FLAG_USER_READ_CNT;
1066 	}
1067 
1068 	/* Only expose micro/arch events supported by this PMU */
1069 	if ((hw_event_id > 0) && (hw_event_id < ARMV8_PMUV3_MAX_COMMON_EVENTS)
1070 	    && test_bit(hw_event_id, armpmu->pmceid_bitmap)) {
1071 		return hw_event_id;
1072 	}
1073 
1074 	return armpmu_map_event(event, extra_event_map, extra_cache_map,
1075 				ARMV8_PMU_EVTYPE_EVENT);
1076 }
1077 
1078 static int armv8_pmuv3_map_event(struct perf_event *event)
1079 {
1080 	return __armv8_pmuv3_map_event(event, NULL, NULL);
1081 }
1082 
1083 static int armv8_a53_map_event(struct perf_event *event)
1084 {
1085 	return __armv8_pmuv3_map_event(event, NULL, &armv8_a53_perf_cache_map);
1086 }
1087 
1088 static int armv8_a57_map_event(struct perf_event *event)
1089 {
1090 	return __armv8_pmuv3_map_event(event, NULL, &armv8_a57_perf_cache_map);
1091 }
1092 
1093 static int armv8_a73_map_event(struct perf_event *event)
1094 {
1095 	return __armv8_pmuv3_map_event(event, NULL, &armv8_a73_perf_cache_map);
1096 }
1097 
1098 static int armv8_thunder_map_event(struct perf_event *event)
1099 {
1100 	return __armv8_pmuv3_map_event(event, NULL,
1101 				       &armv8_thunder_perf_cache_map);
1102 }
1103 
1104 static int armv8_vulcan_map_event(struct perf_event *event)
1105 {
1106 	return __armv8_pmuv3_map_event(event, NULL,
1107 				       &armv8_vulcan_perf_cache_map);
1108 }
1109 
1110 struct armv8pmu_probe_info {
1111 	struct arm_pmu *pmu;
1112 	bool present;
1113 };
1114 
1115 static void __armv8pmu_probe_pmu(void *info)
1116 {
1117 	struct armv8pmu_probe_info *probe = info;
1118 	struct arm_pmu *cpu_pmu = probe->pmu;
1119 	u64 pmceid_raw[2];
1120 	u32 pmceid[2];
1121 	int pmuver;
1122 
1123 	pmuver = read_pmuver();
1124 	if (!pmuv3_implemented(pmuver))
1125 		return;
1126 
1127 	cpu_pmu->pmuver = pmuver;
1128 	probe->present = true;
1129 
1130 	/* Read the nb of CNTx counters supported from PMNC */
1131 	cpu_pmu->num_events = (armv8pmu_pmcr_read() >> ARMV8_PMU_PMCR_N_SHIFT)
1132 		& ARMV8_PMU_PMCR_N_MASK;
1133 
1134 	/* Add the CPU cycles counter */
1135 	cpu_pmu->num_events += 1;
1136 
1137 	pmceid[0] = pmceid_raw[0] = read_pmceid0();
1138 	pmceid[1] = pmceid_raw[1] = read_pmceid1();
1139 
1140 	bitmap_from_arr32(cpu_pmu->pmceid_bitmap,
1141 			     pmceid, ARMV8_PMUV3_MAX_COMMON_EVENTS);
1142 
1143 	pmceid[0] = pmceid_raw[0] >> 32;
1144 	pmceid[1] = pmceid_raw[1] >> 32;
1145 
1146 	bitmap_from_arr32(cpu_pmu->pmceid_ext_bitmap,
1147 			     pmceid, ARMV8_PMUV3_MAX_COMMON_EVENTS);
1148 
1149 	/* store PMMIR register for sysfs */
1150 	if (is_pmuv3p4(pmuver) && (pmceid_raw[1] & BIT(31)))
1151 		cpu_pmu->reg_pmmir = read_pmmir();
1152 	else
1153 		cpu_pmu->reg_pmmir = 0;
1154 }
1155 
1156 static int armv8pmu_probe_pmu(struct arm_pmu *cpu_pmu)
1157 {
1158 	struct armv8pmu_probe_info probe = {
1159 		.pmu = cpu_pmu,
1160 		.present = false,
1161 	};
1162 	int ret;
1163 
1164 	ret = smp_call_function_any(&cpu_pmu->supported_cpus,
1165 				    __armv8pmu_probe_pmu,
1166 				    &probe, 1);
1167 	if (ret)
1168 		return ret;
1169 
1170 	return probe.present ? 0 : -ENODEV;
1171 }
1172 
1173 static void armv8pmu_disable_user_access_ipi(void *unused)
1174 {
1175 	armv8pmu_disable_user_access();
1176 }
1177 
1178 static int armv8pmu_proc_user_access_handler(struct ctl_table *table, int write,
1179 		void *buffer, size_t *lenp, loff_t *ppos)
1180 {
1181 	int ret = proc_dointvec_minmax(table, write, buffer, lenp, ppos);
1182 	if (ret || !write || sysctl_perf_user_access)
1183 		return ret;
1184 
1185 	on_each_cpu(armv8pmu_disable_user_access_ipi, NULL, 1);
1186 	return 0;
1187 }
1188 
1189 static struct ctl_table armv8_pmu_sysctl_table[] = {
1190 	{
1191 		.procname       = "perf_user_access",
1192 		.data		= &sysctl_perf_user_access,
1193 		.maxlen		= sizeof(unsigned int),
1194 		.mode           = 0644,
1195 		.proc_handler	= armv8pmu_proc_user_access_handler,
1196 		.extra1		= SYSCTL_ZERO,
1197 		.extra2		= SYSCTL_ONE,
1198 	},
1199 	{ }
1200 };
1201 
1202 static void armv8_pmu_register_sysctl_table(void)
1203 {
1204 	static u32 tbl_registered = 0;
1205 
1206 	if (!cmpxchg_relaxed(&tbl_registered, 0, 1))
1207 		register_sysctl("kernel", armv8_pmu_sysctl_table);
1208 }
1209 
1210 static int armv8_pmu_init(struct arm_pmu *cpu_pmu, char *name,
1211 			  int (*map_event)(struct perf_event *event),
1212 			  const struct attribute_group *events,
1213 			  const struct attribute_group *format,
1214 			  const struct attribute_group *caps)
1215 {
1216 	int ret = armv8pmu_probe_pmu(cpu_pmu);
1217 	if (ret)
1218 		return ret;
1219 
1220 	cpu_pmu->handle_irq		= armv8pmu_handle_irq;
1221 	cpu_pmu->enable			= armv8pmu_enable_event;
1222 	cpu_pmu->disable		= armv8pmu_disable_event;
1223 	cpu_pmu->read_counter		= armv8pmu_read_counter;
1224 	cpu_pmu->write_counter		= armv8pmu_write_counter;
1225 	cpu_pmu->get_event_idx		= armv8pmu_get_event_idx;
1226 	cpu_pmu->clear_event_idx	= armv8pmu_clear_event_idx;
1227 	cpu_pmu->start			= armv8pmu_start;
1228 	cpu_pmu->stop			= armv8pmu_stop;
1229 	cpu_pmu->reset			= armv8pmu_reset;
1230 	cpu_pmu->set_event_filter	= armv8pmu_set_event_filter;
1231 
1232 	cpu_pmu->pmu.event_idx		= armv8pmu_user_event_idx;
1233 
1234 	cpu_pmu->name			= name;
1235 	cpu_pmu->map_event		= map_event;
1236 	cpu_pmu->attr_groups[ARMPMU_ATTR_GROUP_EVENTS] = events ?
1237 			events : &armv8_pmuv3_events_attr_group;
1238 	cpu_pmu->attr_groups[ARMPMU_ATTR_GROUP_FORMATS] = format ?
1239 			format : &armv8_pmuv3_format_attr_group;
1240 	cpu_pmu->attr_groups[ARMPMU_ATTR_GROUP_CAPS] = caps ?
1241 			caps : &armv8_pmuv3_caps_attr_group;
1242 
1243 	armv8_pmu_register_sysctl_table();
1244 	return 0;
1245 }
1246 
1247 static int armv8_pmu_init_nogroups(struct arm_pmu *cpu_pmu, char *name,
1248 				   int (*map_event)(struct perf_event *event))
1249 {
1250 	return armv8_pmu_init(cpu_pmu, name, map_event, NULL, NULL, NULL);
1251 }
1252 
1253 #define PMUV3_INIT_SIMPLE(name)						\
1254 static int name##_pmu_init(struct arm_pmu *cpu_pmu)			\
1255 {									\
1256 	return armv8_pmu_init_nogroups(cpu_pmu, #name, armv8_pmuv3_map_event);\
1257 }
1258 
1259 PMUV3_INIT_SIMPLE(armv8_pmuv3)
1260 
1261 PMUV3_INIT_SIMPLE(armv8_cortex_a34)
1262 PMUV3_INIT_SIMPLE(armv8_cortex_a55)
1263 PMUV3_INIT_SIMPLE(armv8_cortex_a65)
1264 PMUV3_INIT_SIMPLE(armv8_cortex_a75)
1265 PMUV3_INIT_SIMPLE(armv8_cortex_a76)
1266 PMUV3_INIT_SIMPLE(armv8_cortex_a77)
1267 PMUV3_INIT_SIMPLE(armv8_cortex_a78)
1268 PMUV3_INIT_SIMPLE(armv9_cortex_a510)
1269 PMUV3_INIT_SIMPLE(armv9_cortex_a710)
1270 PMUV3_INIT_SIMPLE(armv8_cortex_x1)
1271 PMUV3_INIT_SIMPLE(armv9_cortex_x2)
1272 PMUV3_INIT_SIMPLE(armv8_neoverse_e1)
1273 PMUV3_INIT_SIMPLE(armv8_neoverse_n1)
1274 PMUV3_INIT_SIMPLE(armv9_neoverse_n2)
1275 PMUV3_INIT_SIMPLE(armv8_neoverse_v1)
1276 
1277 PMUV3_INIT_SIMPLE(armv8_nvidia_carmel)
1278 PMUV3_INIT_SIMPLE(armv8_nvidia_denver)
1279 
1280 static int armv8_a35_pmu_init(struct arm_pmu *cpu_pmu)
1281 {
1282 	return armv8_pmu_init_nogroups(cpu_pmu, "armv8_cortex_a35",
1283 				       armv8_a53_map_event);
1284 }
1285 
1286 static int armv8_a53_pmu_init(struct arm_pmu *cpu_pmu)
1287 {
1288 	return armv8_pmu_init_nogroups(cpu_pmu, "armv8_cortex_a53",
1289 				       armv8_a53_map_event);
1290 }
1291 
1292 static int armv8_a57_pmu_init(struct arm_pmu *cpu_pmu)
1293 {
1294 	return armv8_pmu_init_nogroups(cpu_pmu, "armv8_cortex_a57",
1295 				       armv8_a57_map_event);
1296 }
1297 
1298 static int armv8_a72_pmu_init(struct arm_pmu *cpu_pmu)
1299 {
1300 	return armv8_pmu_init_nogroups(cpu_pmu, "armv8_cortex_a72",
1301 				       armv8_a57_map_event);
1302 }
1303 
1304 static int armv8_a73_pmu_init(struct arm_pmu *cpu_pmu)
1305 {
1306 	return armv8_pmu_init_nogroups(cpu_pmu, "armv8_cortex_a73",
1307 				       armv8_a73_map_event);
1308 }
1309 
1310 static int armv8_thunder_pmu_init(struct arm_pmu *cpu_pmu)
1311 {
1312 	return armv8_pmu_init_nogroups(cpu_pmu, "armv8_cavium_thunder",
1313 				       armv8_thunder_map_event);
1314 }
1315 
1316 static int armv8_vulcan_pmu_init(struct arm_pmu *cpu_pmu)
1317 {
1318 	return armv8_pmu_init_nogroups(cpu_pmu, "armv8_brcm_vulcan",
1319 				       armv8_vulcan_map_event);
1320 }
1321 
1322 static const struct of_device_id armv8_pmu_of_device_ids[] = {
1323 	{.compatible = "arm,armv8-pmuv3",	.data = armv8_pmuv3_pmu_init},
1324 	{.compatible = "arm,cortex-a34-pmu",	.data = armv8_cortex_a34_pmu_init},
1325 	{.compatible = "arm,cortex-a35-pmu",	.data = armv8_a35_pmu_init},
1326 	{.compatible = "arm,cortex-a53-pmu",	.data = armv8_a53_pmu_init},
1327 	{.compatible = "arm,cortex-a55-pmu",	.data = armv8_cortex_a55_pmu_init},
1328 	{.compatible = "arm,cortex-a57-pmu",	.data = armv8_a57_pmu_init},
1329 	{.compatible = "arm,cortex-a65-pmu",	.data = armv8_cortex_a65_pmu_init},
1330 	{.compatible = "arm,cortex-a72-pmu",	.data = armv8_a72_pmu_init},
1331 	{.compatible = "arm,cortex-a73-pmu",	.data = armv8_a73_pmu_init},
1332 	{.compatible = "arm,cortex-a75-pmu",	.data = armv8_cortex_a75_pmu_init},
1333 	{.compatible = "arm,cortex-a76-pmu",	.data = armv8_cortex_a76_pmu_init},
1334 	{.compatible = "arm,cortex-a77-pmu",	.data = armv8_cortex_a77_pmu_init},
1335 	{.compatible = "arm,cortex-a78-pmu",	.data = armv8_cortex_a78_pmu_init},
1336 	{.compatible = "arm,cortex-a510-pmu",	.data = armv9_cortex_a510_pmu_init},
1337 	{.compatible = "arm,cortex-a710-pmu",	.data = armv9_cortex_a710_pmu_init},
1338 	{.compatible = "arm,cortex-x1-pmu",	.data = armv8_cortex_x1_pmu_init},
1339 	{.compatible = "arm,cortex-x2-pmu",	.data = armv9_cortex_x2_pmu_init},
1340 	{.compatible = "arm,neoverse-e1-pmu",	.data = armv8_neoverse_e1_pmu_init},
1341 	{.compatible = "arm,neoverse-n1-pmu",	.data = armv8_neoverse_n1_pmu_init},
1342 	{.compatible = "arm,neoverse-n2-pmu",	.data = armv9_neoverse_n2_pmu_init},
1343 	{.compatible = "arm,neoverse-v1-pmu",	.data = armv8_neoverse_v1_pmu_init},
1344 	{.compatible = "cavium,thunder-pmu",	.data = armv8_thunder_pmu_init},
1345 	{.compatible = "brcm,vulcan-pmu",	.data = armv8_vulcan_pmu_init},
1346 	{.compatible = "nvidia,carmel-pmu",	.data = armv8_nvidia_carmel_pmu_init},
1347 	{.compatible = "nvidia,denver-pmu",	.data = armv8_nvidia_denver_pmu_init},
1348 	{},
1349 };
1350 
1351 static int armv8_pmu_device_probe(struct platform_device *pdev)
1352 {
1353 	return arm_pmu_device_probe(pdev, armv8_pmu_of_device_ids, NULL);
1354 }
1355 
1356 static struct platform_driver armv8_pmu_driver = {
1357 	.driver		= {
1358 		.name	= ARMV8_PMU_PDEV_NAME,
1359 		.of_match_table = armv8_pmu_of_device_ids,
1360 		.suppress_bind_attrs = true,
1361 	},
1362 	.probe		= armv8_pmu_device_probe,
1363 };
1364 
1365 static int __init armv8_pmu_driver_init(void)
1366 {
1367 	int ret;
1368 
1369 	if (acpi_disabled)
1370 		ret = platform_driver_register(&armv8_pmu_driver);
1371 	else
1372 		ret = arm_pmu_acpi_probe(armv8_pmuv3_pmu_init);
1373 
1374 	if (!ret)
1375 		lockup_detector_retry_init();
1376 
1377 	return ret;
1378 }
1379 device_initcall(armv8_pmu_driver_init)
1380 
1381 void arch_perf_update_userpage(struct perf_event *event,
1382 			       struct perf_event_mmap_page *userpg, u64 now)
1383 {
1384 	struct clock_read_data *rd;
1385 	unsigned int seq;
1386 	u64 ns;
1387 
1388 	userpg->cap_user_time = 0;
1389 	userpg->cap_user_time_zero = 0;
1390 	userpg->cap_user_time_short = 0;
1391 	userpg->cap_user_rdpmc = armv8pmu_event_has_user_read(event);
1392 
1393 	if (userpg->cap_user_rdpmc) {
1394 		if (event->hw.flags & ARMPMU_EVT_64BIT)
1395 			userpg->pmc_width = 64;
1396 		else
1397 			userpg->pmc_width = 32;
1398 	}
1399 
1400 	do {
1401 		rd = sched_clock_read_begin(&seq);
1402 
1403 		if (rd->read_sched_clock != arch_timer_read_counter)
1404 			return;
1405 
1406 		userpg->time_mult = rd->mult;
1407 		userpg->time_shift = rd->shift;
1408 		userpg->time_zero = rd->epoch_ns;
1409 		userpg->time_cycles = rd->epoch_cyc;
1410 		userpg->time_mask = rd->sched_clock_mask;
1411 
1412 		/*
1413 		 * Subtract the cycle base, such that software that
1414 		 * doesn't know about cap_user_time_short still 'works'
1415 		 * assuming no wraps.
1416 		 */
1417 		ns = mul_u64_u32_shr(rd->epoch_cyc, rd->mult, rd->shift);
1418 		userpg->time_zero -= ns;
1419 
1420 	} while (sched_clock_read_retry(seq));
1421 
1422 	userpg->time_offset = userpg->time_zero - now;
1423 
1424 	/*
1425 	 * time_shift is not expected to be greater than 31 due to
1426 	 * the original published conversion algorithm shifting a
1427 	 * 32-bit value (now specifies a 64-bit value) - refer
1428 	 * perf_event_mmap_page documentation in perf_event.h.
1429 	 */
1430 	if (userpg->time_shift == 32) {
1431 		userpg->time_shift = 31;
1432 		userpg->time_mult >>= 1;
1433 	}
1434 
1435 	/*
1436 	 * Internal timekeeping for enabled/running/stopped times
1437 	 * is always computed with the sched_clock.
1438 	 */
1439 	userpg->cap_user_time = 1;
1440 	userpg->cap_user_time_zero = 1;
1441 	userpg->cap_user_time_short = 1;
1442 }
1443