xref: /linux/arch/x86/events/amd/core.c (revision a36e9f5cfe9eb3a1dce8769c7058251c42705357)
1 // SPDX-License-Identifier: GPL-2.0-only
2 #include <linux/perf_event.h>
3 #include <linux/jump_label.h>
4 #include <linux/export.h>
5 #include <linux/types.h>
6 #include <linux/init.h>
7 #include <linux/slab.h>
8 #include <linux/delay.h>
9 #include <linux/jiffies.h>
10 #include <asm/apicdef.h>
11 #include <asm/apic.h>
12 #include <asm/nmi.h>
13 
14 #include "../perf_event.h"
15 
16 static DEFINE_PER_CPU(unsigned long, perf_nmi_tstamp);
17 static unsigned long perf_nmi_window;
18 
19 /* AMD Event 0xFFF: Merge.  Used with Large Increment per Cycle events */
20 #define AMD_MERGE_EVENT ((0xFULL << 32) | 0xFFULL)
21 #define AMD_MERGE_EVENT_ENABLE (AMD_MERGE_EVENT | ARCH_PERFMON_EVENTSEL_ENABLE)
22 
23 /* PMC Enable and Overflow bits for PerfCntrGlobal* registers */
24 static u64 amd_pmu_global_cntr_mask __read_mostly;
25 
26 static __initconst const u64 amd_hw_cache_event_ids
27 				[PERF_COUNT_HW_CACHE_MAX]
28 				[PERF_COUNT_HW_CACHE_OP_MAX]
29 				[PERF_COUNT_HW_CACHE_RESULT_MAX] =
30 {
31  [ C(L1D) ] = {
32 	[ C(OP_READ) ] = {
33 		[ C(RESULT_ACCESS) ] = 0x0040, /* Data Cache Accesses        */
34 		[ C(RESULT_MISS)   ] = 0x0141, /* Data Cache Misses          */
35 	},
36 	[ C(OP_WRITE) ] = {
37 		[ C(RESULT_ACCESS) ] = 0,
38 		[ C(RESULT_MISS)   ] = 0,
39 	},
40 	[ C(OP_PREFETCH) ] = {
41 		[ C(RESULT_ACCESS) ] = 0x0267, /* Data Prefetcher :attempts  */
42 		[ C(RESULT_MISS)   ] = 0x0167, /* Data Prefetcher :cancelled */
43 	},
44  },
45  [ C(L1I ) ] = {
46 	[ C(OP_READ) ] = {
47 		[ C(RESULT_ACCESS) ] = 0x0080, /* Instruction cache fetches  */
48 		[ C(RESULT_MISS)   ] = 0x0081, /* Instruction cache misses   */
49 	},
50 	[ C(OP_WRITE) ] = {
51 		[ C(RESULT_ACCESS) ] = -1,
52 		[ C(RESULT_MISS)   ] = -1,
53 	},
54 	[ C(OP_PREFETCH) ] = {
55 		[ C(RESULT_ACCESS) ] = 0x014B, /* Prefetch Instructions :Load */
56 		[ C(RESULT_MISS)   ] = 0,
57 	},
58  },
59  [ C(LL  ) ] = {
60 	[ C(OP_READ) ] = {
61 		[ C(RESULT_ACCESS) ] = 0x037D, /* Requests to L2 Cache :IC+DC */
62 		[ C(RESULT_MISS)   ] = 0x037E, /* L2 Cache Misses : IC+DC     */
63 	},
64 	[ C(OP_WRITE) ] = {
65 		[ C(RESULT_ACCESS) ] = 0x017F, /* L2 Fill/Writeback           */
66 		[ C(RESULT_MISS)   ] = 0,
67 	},
68 	[ C(OP_PREFETCH) ] = {
69 		[ C(RESULT_ACCESS) ] = 0,
70 		[ C(RESULT_MISS)   ] = 0,
71 	},
72  },
73  [ C(DTLB) ] = {
74 	[ C(OP_READ) ] = {
75 		[ C(RESULT_ACCESS) ] = 0x0040, /* Data Cache Accesses        */
76 		[ C(RESULT_MISS)   ] = 0x0746, /* L1_DTLB_AND_L2_DLTB_MISS.ALL */
77 	},
78 	[ C(OP_WRITE) ] = {
79 		[ C(RESULT_ACCESS) ] = 0,
80 		[ C(RESULT_MISS)   ] = 0,
81 	},
82 	[ C(OP_PREFETCH) ] = {
83 		[ C(RESULT_ACCESS) ] = 0,
84 		[ C(RESULT_MISS)   ] = 0,
85 	},
86  },
87  [ C(ITLB) ] = {
88 	[ C(OP_READ) ] = {
89 		[ C(RESULT_ACCESS) ] = 0x0080, /* Instruction fecthes        */
90 		[ C(RESULT_MISS)   ] = 0x0385, /* L1_ITLB_AND_L2_ITLB_MISS.ALL */
91 	},
92 	[ C(OP_WRITE) ] = {
93 		[ C(RESULT_ACCESS) ] = -1,
94 		[ C(RESULT_MISS)   ] = -1,
95 	},
96 	[ C(OP_PREFETCH) ] = {
97 		[ C(RESULT_ACCESS) ] = -1,
98 		[ C(RESULT_MISS)   ] = -1,
99 	},
100  },
101  [ C(BPU ) ] = {
102 	[ C(OP_READ) ] = {
103 		[ C(RESULT_ACCESS) ] = 0x00c2, /* Retired Branch Instr.      */
104 		[ C(RESULT_MISS)   ] = 0x00c3, /* Retired Mispredicted BI    */
105 	},
106 	[ C(OP_WRITE) ] = {
107 		[ C(RESULT_ACCESS) ] = -1,
108 		[ C(RESULT_MISS)   ] = -1,
109 	},
110 	[ C(OP_PREFETCH) ] = {
111 		[ C(RESULT_ACCESS) ] = -1,
112 		[ C(RESULT_MISS)   ] = -1,
113 	},
114  },
115  [ C(NODE) ] = {
116 	[ C(OP_READ) ] = {
117 		[ C(RESULT_ACCESS) ] = 0xb8e9, /* CPU Request to Memory, l+r */
118 		[ C(RESULT_MISS)   ] = 0x98e9, /* CPU Request to Memory, r   */
119 	},
120 	[ C(OP_WRITE) ] = {
121 		[ C(RESULT_ACCESS) ] = -1,
122 		[ C(RESULT_MISS)   ] = -1,
123 	},
124 	[ C(OP_PREFETCH) ] = {
125 		[ C(RESULT_ACCESS) ] = -1,
126 		[ C(RESULT_MISS)   ] = -1,
127 	},
128  },
129 };
130 
131 static __initconst const u64 amd_hw_cache_event_ids_f17h
132 				[PERF_COUNT_HW_CACHE_MAX]
133 				[PERF_COUNT_HW_CACHE_OP_MAX]
134 				[PERF_COUNT_HW_CACHE_RESULT_MAX] = {
135 [C(L1D)] = {
136 	[C(OP_READ)] = {
137 		[C(RESULT_ACCESS)] = 0x0040, /* Data Cache Accesses */
138 		[C(RESULT_MISS)]   = 0xc860, /* L2$ access from DC Miss */
139 	},
140 	[C(OP_WRITE)] = {
141 		[C(RESULT_ACCESS)] = 0,
142 		[C(RESULT_MISS)]   = 0,
143 	},
144 	[C(OP_PREFETCH)] = {
145 		[C(RESULT_ACCESS)] = 0xff5a, /* h/w prefetch DC Fills */
146 		[C(RESULT_MISS)]   = 0,
147 	},
148 },
149 [C(L1I)] = {
150 	[C(OP_READ)] = {
151 		[C(RESULT_ACCESS)] = 0x0080, /* Instruction cache fetches  */
152 		[C(RESULT_MISS)]   = 0x0081, /* Instruction cache misses   */
153 	},
154 	[C(OP_WRITE)] = {
155 		[C(RESULT_ACCESS)] = -1,
156 		[C(RESULT_MISS)]   = -1,
157 	},
158 	[C(OP_PREFETCH)] = {
159 		[C(RESULT_ACCESS)] = 0,
160 		[C(RESULT_MISS)]   = 0,
161 	},
162 },
163 [C(LL)] = {
164 	[C(OP_READ)] = {
165 		[C(RESULT_ACCESS)] = 0,
166 		[C(RESULT_MISS)]   = 0,
167 	},
168 	[C(OP_WRITE)] = {
169 		[C(RESULT_ACCESS)] = 0,
170 		[C(RESULT_MISS)]   = 0,
171 	},
172 	[C(OP_PREFETCH)] = {
173 		[C(RESULT_ACCESS)] = 0,
174 		[C(RESULT_MISS)]   = 0,
175 	},
176 },
177 [C(DTLB)] = {
178 	[C(OP_READ)] = {
179 		[C(RESULT_ACCESS)] = 0xff45, /* All L2 DTLB accesses */
180 		[C(RESULT_MISS)]   = 0xf045, /* L2 DTLB misses (PT walks) */
181 	},
182 	[C(OP_WRITE)] = {
183 		[C(RESULT_ACCESS)] = 0,
184 		[C(RESULT_MISS)]   = 0,
185 	},
186 	[C(OP_PREFETCH)] = {
187 		[C(RESULT_ACCESS)] = 0,
188 		[C(RESULT_MISS)]   = 0,
189 	},
190 },
191 [C(ITLB)] = {
192 	[C(OP_READ)] = {
193 		[C(RESULT_ACCESS)] = 0x0084, /* L1 ITLB misses, L2 ITLB hits */
194 		[C(RESULT_MISS)]   = 0xff85, /* L1 ITLB misses, L2 misses */
195 	},
196 	[C(OP_WRITE)] = {
197 		[C(RESULT_ACCESS)] = -1,
198 		[C(RESULT_MISS)]   = -1,
199 	},
200 	[C(OP_PREFETCH)] = {
201 		[C(RESULT_ACCESS)] = -1,
202 		[C(RESULT_MISS)]   = -1,
203 	},
204 },
205 [C(BPU)] = {
206 	[C(OP_READ)] = {
207 		[C(RESULT_ACCESS)] = 0x00c2, /* Retired Branch Instr.      */
208 		[C(RESULT_MISS)]   = 0x00c3, /* Retired Mispredicted BI    */
209 	},
210 	[C(OP_WRITE)] = {
211 		[C(RESULT_ACCESS)] = -1,
212 		[C(RESULT_MISS)]   = -1,
213 	},
214 	[C(OP_PREFETCH)] = {
215 		[C(RESULT_ACCESS)] = -1,
216 		[C(RESULT_MISS)]   = -1,
217 	},
218 },
219 [C(NODE)] = {
220 	[C(OP_READ)] = {
221 		[C(RESULT_ACCESS)] = 0,
222 		[C(RESULT_MISS)]   = 0,
223 	},
224 	[C(OP_WRITE)] = {
225 		[C(RESULT_ACCESS)] = -1,
226 		[C(RESULT_MISS)]   = -1,
227 	},
228 	[C(OP_PREFETCH)] = {
229 		[C(RESULT_ACCESS)] = -1,
230 		[C(RESULT_MISS)]   = -1,
231 	},
232 },
233 };
234 
235 /*
236  * AMD Performance Monitor K7 and later, up to and including Family 16h:
237  */
238 static const u64 amd_perfmon_event_map[PERF_COUNT_HW_MAX] =
239 {
240 	[PERF_COUNT_HW_CPU_CYCLES]		= 0x0076,
241 	[PERF_COUNT_HW_INSTRUCTIONS]		= 0x00c0,
242 	[PERF_COUNT_HW_CACHE_REFERENCES]	= 0x077d,
243 	[PERF_COUNT_HW_CACHE_MISSES]		= 0x077e,
244 	[PERF_COUNT_HW_BRANCH_INSTRUCTIONS]	= 0x00c2,
245 	[PERF_COUNT_HW_BRANCH_MISSES]		= 0x00c3,
246 	[PERF_COUNT_HW_STALLED_CYCLES_FRONTEND]	= 0x00d0, /* "Decoder empty" event */
247 	[PERF_COUNT_HW_STALLED_CYCLES_BACKEND]	= 0x00d1, /* "Dispatch stalls" event */
248 };
249 
250 /*
251  * AMD Performance Monitor Family 17h and later:
252  */
253 static const u64 amd_zen1_perfmon_event_map[PERF_COUNT_HW_MAX] =
254 {
255 	[PERF_COUNT_HW_CPU_CYCLES]		= 0x0076,
256 	[PERF_COUNT_HW_INSTRUCTIONS]		= 0x00c0,
257 	[PERF_COUNT_HW_CACHE_REFERENCES]	= 0xff60,
258 	[PERF_COUNT_HW_CACHE_MISSES]		= 0x0964,
259 	[PERF_COUNT_HW_BRANCH_INSTRUCTIONS]	= 0x00c2,
260 	[PERF_COUNT_HW_BRANCH_MISSES]		= 0x00c3,
261 	[PERF_COUNT_HW_STALLED_CYCLES_FRONTEND]	= 0x0287,
262 	[PERF_COUNT_HW_STALLED_CYCLES_BACKEND]	= 0x0187,
263 };
264 
265 static const u64 amd_zen2_perfmon_event_map[PERF_COUNT_HW_MAX] =
266 {
267 	[PERF_COUNT_HW_CPU_CYCLES]		= 0x0076,
268 	[PERF_COUNT_HW_INSTRUCTIONS]		= 0x00c0,
269 	[PERF_COUNT_HW_CACHE_REFERENCES]	= 0xff60,
270 	[PERF_COUNT_HW_CACHE_MISSES]		= 0x0964,
271 	[PERF_COUNT_HW_BRANCH_INSTRUCTIONS]	= 0x00c2,
272 	[PERF_COUNT_HW_BRANCH_MISSES]		= 0x00c3,
273 	[PERF_COUNT_HW_STALLED_CYCLES_FRONTEND]	= 0x00a9,
274 };
275 
276 static const u64 amd_zen4_perfmon_event_map[PERF_COUNT_HW_MAX] =
277 {
278 	[PERF_COUNT_HW_CPU_CYCLES]		= 0x0076,
279 	[PERF_COUNT_HW_INSTRUCTIONS]		= 0x00c0,
280 	[PERF_COUNT_HW_CACHE_REFERENCES]	= 0xff60,
281 	[PERF_COUNT_HW_CACHE_MISSES]		= 0x0964,
282 	[PERF_COUNT_HW_BRANCH_INSTRUCTIONS]	= 0x00c2,
283 	[PERF_COUNT_HW_BRANCH_MISSES]		= 0x00c3,
284 	[PERF_COUNT_HW_STALLED_CYCLES_FRONTEND]	= 0x00a9,
285 	[PERF_COUNT_HW_REF_CPU_CYCLES]		= 0x100000120,
286 };
287 
288 static u64 amd_pmu_event_map(int hw_event)
289 {
290 	if (cpu_feature_enabled(X86_FEATURE_ZEN4) || boot_cpu_data.x86 >= 0x1a)
291 		return amd_zen4_perfmon_event_map[hw_event];
292 
293 	if (cpu_feature_enabled(X86_FEATURE_ZEN2) || boot_cpu_data.x86 >= 0x19)
294 		return amd_zen2_perfmon_event_map[hw_event];
295 
296 	if (cpu_feature_enabled(X86_FEATURE_ZEN1))
297 		return amd_zen1_perfmon_event_map[hw_event];
298 
299 	return amd_perfmon_event_map[hw_event];
300 }
301 
302 /*
303  * Previously calculated offsets
304  */
305 static unsigned int event_offsets[X86_PMC_IDX_MAX] __read_mostly;
306 static unsigned int count_offsets[X86_PMC_IDX_MAX] __read_mostly;
307 
308 /*
309  * Legacy CPUs:
310  *   4 counters starting at 0xc0010000 each offset by 1
311  *
312  * CPUs with core performance counter extensions:
313  *   6 counters starting at 0xc0010200 each offset by 2
314  */
315 static inline int amd_pmu_addr_offset(int index, bool eventsel)
316 {
317 	int offset;
318 
319 	if (!index)
320 		return index;
321 
322 	if (eventsel)
323 		offset = event_offsets[index];
324 	else
325 		offset = count_offsets[index];
326 
327 	if (offset)
328 		return offset;
329 
330 	if (!boot_cpu_has(X86_FEATURE_PERFCTR_CORE))
331 		offset = index;
332 	else
333 		offset = index << 1;
334 
335 	if (eventsel)
336 		event_offsets[index] = offset;
337 	else
338 		count_offsets[index] = offset;
339 
340 	return offset;
341 }
342 
343 /*
344  * AMD64 events are detected based on their event codes.
345  */
346 static inline unsigned int amd_get_event_code(struct hw_perf_event *hwc)
347 {
348 	return ((hwc->config >> 24) & 0x0f00) | (hwc->config & 0x00ff);
349 }
350 
351 static inline bool amd_is_pair_event_code(struct hw_perf_event *hwc)
352 {
353 	if (!(x86_pmu.flags & PMU_FL_PAIR))
354 		return false;
355 
356 	switch (amd_get_event_code(hwc)) {
357 	case 0x003:	return true;	/* Retired SSE/AVX FLOPs */
358 	default:	return false;
359 	}
360 }
361 
362 DEFINE_STATIC_CALL_RET0(amd_pmu_branch_hw_config, *x86_pmu.hw_config);
363 
364 static int amd_core_hw_config(struct perf_event *event)
365 {
366 	if (event->attr.exclude_host && event->attr.exclude_guest)
367 		/*
368 		 * When HO == GO == 1 the hardware treats that as GO == HO == 0
369 		 * and will count in both modes. We don't want to count in that
370 		 * case so we emulate no-counting by setting US = OS = 0.
371 		 */
372 		event->hw.config &= ~(ARCH_PERFMON_EVENTSEL_USR |
373 				      ARCH_PERFMON_EVENTSEL_OS);
374 	else if (event->attr.exclude_host)
375 		event->hw.config |= AMD64_EVENTSEL_GUESTONLY;
376 	else if (event->attr.exclude_guest)
377 		event->hw.config |= AMD64_EVENTSEL_HOSTONLY;
378 
379 	if ((x86_pmu.flags & PMU_FL_PAIR) && amd_is_pair_event_code(&event->hw))
380 		event->hw.flags |= PERF_X86_EVENT_PAIR;
381 
382 	if (has_branch_stack(event))
383 		return static_call(amd_pmu_branch_hw_config)(event);
384 
385 	return 0;
386 }
387 
388 static inline int amd_is_nb_event(struct hw_perf_event *hwc)
389 {
390 	return (hwc->config & 0xe0) == 0xe0;
391 }
392 
393 static inline int amd_has_nb(struct cpu_hw_events *cpuc)
394 {
395 	struct amd_nb *nb = cpuc->amd_nb;
396 
397 	return nb && nb->nb_id != -1;
398 }
399 
400 static int amd_pmu_hw_config(struct perf_event *event)
401 {
402 	int ret;
403 
404 	/* pass precise event sampling to ibs: */
405 	if (event->attr.precise_ip && get_ibs_caps())
406 		return forward_event_to_ibs(event);
407 
408 	if (has_branch_stack(event) && !x86_pmu.lbr_nr)
409 		return -EOPNOTSUPP;
410 
411 	ret = x86_pmu_hw_config(event);
412 	if (ret)
413 		return ret;
414 
415 	if (event->attr.type == PERF_TYPE_RAW)
416 		event->hw.config |= event->attr.config & AMD64_RAW_EVENT_MASK;
417 
418 	return amd_core_hw_config(event);
419 }
420 
421 static void __amd_put_nb_event_constraints(struct cpu_hw_events *cpuc,
422 					   struct perf_event *event)
423 {
424 	struct amd_nb *nb = cpuc->amd_nb;
425 	int i;
426 
427 	/*
428 	 * need to scan whole list because event may not have
429 	 * been assigned during scheduling
430 	 *
431 	 * no race condition possible because event can only
432 	 * be removed on one CPU at a time AND PMU is disabled
433 	 * when we come here
434 	 */
435 	for_each_set_bit(i, x86_pmu.cntr_mask, X86_PMC_IDX_MAX) {
436 		struct perf_event *tmp = event;
437 
438 		if (try_cmpxchg(nb->owners + i, &tmp, NULL))
439 			break;
440 	}
441 }
442 
443  /*
444   * AMD64 NorthBridge events need special treatment because
445   * counter access needs to be synchronized across all cores
446   * of a package. Refer to BKDG section 3.12
447   *
448   * NB events are events measuring L3 cache, Hypertransport
449   * traffic. They are identified by an event code >= 0xe00.
450   * They measure events on the NorthBride which is shared
451   * by all cores on a package. NB events are counted on a
452   * shared set of counters. When a NB event is programmed
453   * in a counter, the data actually comes from a shared
454   * counter. Thus, access to those counters needs to be
455   * synchronized.
456   *
457   * We implement the synchronization such that no two cores
458   * can be measuring NB events using the same counters. Thus,
459   * we maintain a per-NB allocation table. The available slot
460   * is propagated using the event_constraint structure.
461   *
462   * We provide only one choice for each NB event based on
463   * the fact that only NB events have restrictions. Consequently,
464   * if a counter is available, there is a guarantee the NB event
465   * will be assigned to it. If no slot is available, an empty
466   * constraint is returned and scheduling will eventually fail
467   * for this event.
468   *
469   * Note that all cores attached the same NB compete for the same
470   * counters to host NB events, this is why we use atomic ops. Some
471   * multi-chip CPUs may have more than one NB.
472   *
473   * Given that resources are allocated (cmpxchg), they must be
474   * eventually freed for others to use. This is accomplished by
475   * calling __amd_put_nb_event_constraints()
476   *
477   * Non NB events are not impacted by this restriction.
478   */
479 static struct event_constraint *
480 __amd_get_nb_event_constraints(struct cpu_hw_events *cpuc, struct perf_event *event,
481 			       struct event_constraint *c)
482 {
483 	struct hw_perf_event *hwc = &event->hw;
484 	struct amd_nb *nb = cpuc->amd_nb;
485 	struct perf_event *old;
486 	int idx, new = -1;
487 
488 	if (!c)
489 		c = &unconstrained;
490 
491 	if (cpuc->is_fake)
492 		return c;
493 
494 	/*
495 	 * detect if already present, if so reuse
496 	 *
497 	 * cannot merge with actual allocation
498 	 * because of possible holes
499 	 *
500 	 * event can already be present yet not assigned (in hwc->idx)
501 	 * because of successive calls to x86_schedule_events() from
502 	 * hw_perf_group_sched_in() without hw_perf_enable()
503 	 */
504 	for_each_set_bit(idx, c->idxmsk, x86_pmu_max_num_counters(NULL)) {
505 		if (new == -1 || hwc->idx == idx)
506 			/* assign free slot, prefer hwc->idx */
507 			old = cmpxchg(nb->owners + idx, NULL, event);
508 		else if (nb->owners[idx] == event)
509 			/* event already present */
510 			old = event;
511 		else
512 			continue;
513 
514 		if (old && old != event)
515 			continue;
516 
517 		/* reassign to this slot */
518 		if (new != -1)
519 			cmpxchg(nb->owners + new, event, NULL);
520 		new = idx;
521 
522 		/* already present, reuse */
523 		if (old == event)
524 			break;
525 	}
526 
527 	if (new == -1)
528 		return &emptyconstraint;
529 
530 	return &nb->event_constraints[new];
531 }
532 
533 static struct amd_nb *amd_alloc_nb(int cpu)
534 {
535 	struct amd_nb *nb;
536 	int i;
537 
538 	nb = kzalloc_node(sizeof(struct amd_nb), GFP_KERNEL, cpu_to_node(cpu));
539 	if (!nb)
540 		return NULL;
541 
542 	nb->nb_id = -1;
543 
544 	/*
545 	 * initialize all possible NB constraints
546 	 */
547 	for_each_set_bit(i, x86_pmu.cntr_mask, X86_PMC_IDX_MAX) {
548 		__set_bit(i, nb->event_constraints[i].idxmsk);
549 		nb->event_constraints[i].weight = 1;
550 	}
551 	return nb;
552 }
553 
554 typedef void (amd_pmu_branch_reset_t)(void);
555 DEFINE_STATIC_CALL_NULL(amd_pmu_branch_reset, amd_pmu_branch_reset_t);
556 
557 static void amd_pmu_cpu_reset(int cpu)
558 {
559 	if (x86_pmu.lbr_nr)
560 		static_call(amd_pmu_branch_reset)();
561 
562 	if (x86_pmu.version < 2)
563 		return;
564 
565 	/* Clear enable bits i.e. PerfCntrGlobalCtl.PerfCntrEn */
566 	wrmsrl(MSR_AMD64_PERF_CNTR_GLOBAL_CTL, 0);
567 
568 	/*
569 	 * Clear freeze and overflow bits i.e. PerfCntrGLobalStatus.LbrFreeze
570 	 * and PerfCntrGLobalStatus.PerfCntrOvfl
571 	 */
572 	wrmsrl(MSR_AMD64_PERF_CNTR_GLOBAL_STATUS_CLR,
573 	       GLOBAL_STATUS_LBRS_FROZEN | amd_pmu_global_cntr_mask);
574 }
575 
576 static int amd_pmu_cpu_prepare(int cpu)
577 {
578 	struct cpu_hw_events *cpuc = &per_cpu(cpu_hw_events, cpu);
579 
580 	cpuc->lbr_sel = kzalloc_node(sizeof(struct er_account), GFP_KERNEL,
581 				     cpu_to_node(cpu));
582 	if (!cpuc->lbr_sel)
583 		return -ENOMEM;
584 
585 	WARN_ON_ONCE(cpuc->amd_nb);
586 
587 	if (!x86_pmu.amd_nb_constraints)
588 		return 0;
589 
590 	cpuc->amd_nb = amd_alloc_nb(cpu);
591 	if (cpuc->amd_nb)
592 		return 0;
593 
594 	kfree(cpuc->lbr_sel);
595 	cpuc->lbr_sel = NULL;
596 
597 	return -ENOMEM;
598 }
599 
600 static void amd_pmu_cpu_starting(int cpu)
601 {
602 	struct cpu_hw_events *cpuc = &per_cpu(cpu_hw_events, cpu);
603 	void **onln = &cpuc->kfree_on_online[X86_PERF_KFREE_SHARED];
604 	struct amd_nb *nb;
605 	int i, nb_id;
606 
607 	cpuc->perf_ctr_virt_mask = AMD64_EVENTSEL_HOSTONLY;
608 	amd_pmu_cpu_reset(cpu);
609 
610 	if (!x86_pmu.amd_nb_constraints)
611 		return;
612 
613 	nb_id = topology_amd_node_id(cpu);
614 	WARN_ON_ONCE(nb_id == BAD_APICID);
615 
616 	for_each_online_cpu(i) {
617 		nb = per_cpu(cpu_hw_events, i).amd_nb;
618 		if (WARN_ON_ONCE(!nb))
619 			continue;
620 
621 		if (nb->nb_id == nb_id) {
622 			*onln = cpuc->amd_nb;
623 			cpuc->amd_nb = nb;
624 			break;
625 		}
626 	}
627 
628 	cpuc->amd_nb->nb_id = nb_id;
629 	cpuc->amd_nb->refcnt++;
630 }
631 
632 static void amd_pmu_cpu_dead(int cpu)
633 {
634 	struct cpu_hw_events *cpuhw = &per_cpu(cpu_hw_events, cpu);
635 
636 	kfree(cpuhw->lbr_sel);
637 	cpuhw->lbr_sel = NULL;
638 
639 	if (!x86_pmu.amd_nb_constraints)
640 		return;
641 
642 	if (cpuhw->amd_nb) {
643 		struct amd_nb *nb = cpuhw->amd_nb;
644 
645 		if (nb->nb_id == -1 || --nb->refcnt == 0)
646 			kfree(nb);
647 
648 		cpuhw->amd_nb = NULL;
649 	}
650 }
651 
652 static __always_inline void amd_pmu_set_global_ctl(u64 ctl)
653 {
654 	wrmsrl(MSR_AMD64_PERF_CNTR_GLOBAL_CTL, ctl);
655 }
656 
657 static inline u64 amd_pmu_get_global_status(void)
658 {
659 	u64 status;
660 
661 	/* PerfCntrGlobalStatus is read-only */
662 	rdmsrl(MSR_AMD64_PERF_CNTR_GLOBAL_STATUS, status);
663 
664 	return status;
665 }
666 
667 static inline void amd_pmu_ack_global_status(u64 status)
668 {
669 	/*
670 	 * PerfCntrGlobalStatus is read-only but an overflow acknowledgment
671 	 * mechanism exists; writing 1 to a bit in PerfCntrGlobalStatusClr
672 	 * clears the same bit in PerfCntrGlobalStatus
673 	 */
674 
675 	wrmsrl(MSR_AMD64_PERF_CNTR_GLOBAL_STATUS_CLR, status);
676 }
677 
678 static bool amd_pmu_test_overflow_topbit(int idx)
679 {
680 	u64 counter;
681 
682 	rdmsrl(x86_pmu_event_addr(idx), counter);
683 
684 	return !(counter & BIT_ULL(x86_pmu.cntval_bits - 1));
685 }
686 
687 static bool amd_pmu_test_overflow_status(int idx)
688 {
689 	return amd_pmu_get_global_status() & BIT_ULL(idx);
690 }
691 
692 DEFINE_STATIC_CALL(amd_pmu_test_overflow, amd_pmu_test_overflow_topbit);
693 
694 /*
695  * When a PMC counter overflows, an NMI is used to process the event and
696  * reset the counter. NMI latency can result in the counter being updated
697  * before the NMI can run, which can result in what appear to be spurious
698  * NMIs. This function is intended to wait for the NMI to run and reset
699  * the counter to avoid possible unhandled NMI messages.
700  */
701 #define OVERFLOW_WAIT_COUNT	50
702 
703 static void amd_pmu_wait_on_overflow(int idx)
704 {
705 	unsigned int i;
706 
707 	/*
708 	 * Wait for the counter to be reset if it has overflowed. This loop
709 	 * should exit very, very quickly, but just in case, don't wait
710 	 * forever...
711 	 */
712 	for (i = 0; i < OVERFLOW_WAIT_COUNT; i++) {
713 		if (!static_call(amd_pmu_test_overflow)(idx))
714 			break;
715 
716 		/* Might be in IRQ context, so can't sleep */
717 		udelay(1);
718 	}
719 }
720 
721 static void amd_pmu_check_overflow(void)
722 {
723 	struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events);
724 	int idx;
725 
726 	/*
727 	 * This shouldn't be called from NMI context, but add a safeguard here
728 	 * to return, since if we're in NMI context we can't wait for an NMI
729 	 * to reset an overflowed counter value.
730 	 */
731 	if (in_nmi())
732 		return;
733 
734 	/*
735 	 * Check each counter for overflow and wait for it to be reset by the
736 	 * NMI if it has overflowed. This relies on the fact that all active
737 	 * counters are always enabled when this function is called and
738 	 * ARCH_PERFMON_EVENTSEL_INT is always set.
739 	 */
740 	for_each_set_bit(idx, x86_pmu.cntr_mask, X86_PMC_IDX_MAX) {
741 		if (!test_bit(idx, cpuc->active_mask))
742 			continue;
743 
744 		amd_pmu_wait_on_overflow(idx);
745 	}
746 }
747 
748 static void amd_pmu_enable_event(struct perf_event *event)
749 {
750 	x86_pmu_enable_event(event);
751 }
752 
753 static void amd_pmu_enable_all(int added)
754 {
755 	struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events);
756 	int idx;
757 
758 	amd_brs_enable_all();
759 
760 	for_each_set_bit(idx, x86_pmu.cntr_mask, X86_PMC_IDX_MAX) {
761 		/* only activate events which are marked as active */
762 		if (!test_bit(idx, cpuc->active_mask))
763 			continue;
764 
765 		amd_pmu_enable_event(cpuc->events[idx]);
766 	}
767 }
768 
769 static void amd_pmu_v2_enable_event(struct perf_event *event)
770 {
771 	struct hw_perf_event *hwc = &event->hw;
772 
773 	/*
774 	 * Testing cpu_hw_events.enabled should be skipped in this case unlike
775 	 * in x86_pmu_enable_event().
776 	 *
777 	 * Since cpu_hw_events.enabled is set only after returning from
778 	 * x86_pmu_start(), the PMCs must be programmed and kept ready.
779 	 * Counting starts only after x86_pmu_enable_all() is called.
780 	 */
781 	__x86_pmu_enable_event(hwc, ARCH_PERFMON_EVENTSEL_ENABLE);
782 }
783 
784 static __always_inline void amd_pmu_core_enable_all(void)
785 {
786 	amd_pmu_set_global_ctl(amd_pmu_global_cntr_mask);
787 }
788 
789 static void amd_pmu_v2_enable_all(int added)
790 {
791 	amd_pmu_lbr_enable_all();
792 	amd_pmu_core_enable_all();
793 }
794 
795 static void amd_pmu_disable_event(struct perf_event *event)
796 {
797 	x86_pmu_disable_event(event);
798 
799 	/*
800 	 * This can be called from NMI context (via x86_pmu_stop). The counter
801 	 * may have overflowed, but either way, we'll never see it get reset
802 	 * by the NMI if we're already in the NMI. And the NMI latency support
803 	 * below will take care of any pending NMI that might have been
804 	 * generated by the overflow.
805 	 */
806 	if (in_nmi())
807 		return;
808 
809 	amd_pmu_wait_on_overflow(event->hw.idx);
810 }
811 
812 static void amd_pmu_disable_all(void)
813 {
814 	amd_brs_disable_all();
815 	x86_pmu_disable_all();
816 	amd_pmu_check_overflow();
817 }
818 
819 static __always_inline void amd_pmu_core_disable_all(void)
820 {
821 	amd_pmu_set_global_ctl(0);
822 }
823 
824 static void amd_pmu_v2_disable_all(void)
825 {
826 	amd_pmu_core_disable_all();
827 	amd_pmu_lbr_disable_all();
828 	amd_pmu_check_overflow();
829 }
830 
831 DEFINE_STATIC_CALL_NULL(amd_pmu_branch_add, *x86_pmu.add);
832 
833 static void amd_pmu_add_event(struct perf_event *event)
834 {
835 	if (needs_branch_stack(event))
836 		static_call(amd_pmu_branch_add)(event);
837 }
838 
839 DEFINE_STATIC_CALL_NULL(amd_pmu_branch_del, *x86_pmu.del);
840 
841 static void amd_pmu_del_event(struct perf_event *event)
842 {
843 	if (needs_branch_stack(event))
844 		static_call(amd_pmu_branch_del)(event);
845 }
846 
847 /*
848  * Because of NMI latency, if multiple PMC counters are active or other sources
849  * of NMIs are received, the perf NMI handler can handle one or more overflowed
850  * PMC counters outside of the NMI associated with the PMC overflow. If the NMI
851  * doesn't arrive at the LAPIC in time to become a pending NMI, then the kernel
852  * back-to-back NMI support won't be active. This PMC handler needs to take into
853  * account that this can occur, otherwise this could result in unknown NMI
854  * messages being issued. Examples of this is PMC overflow while in the NMI
855  * handler when multiple PMCs are active or PMC overflow while handling some
856  * other source of an NMI.
857  *
858  * Attempt to mitigate this by creating an NMI window in which un-handled NMIs
859  * received during this window will be claimed. This prevents extending the
860  * window past when it is possible that latent NMIs should be received. The
861  * per-CPU perf_nmi_tstamp will be set to the window end time whenever perf has
862  * handled a counter. When an un-handled NMI is received, it will be claimed
863  * only if arriving within that window.
864  */
865 static inline int amd_pmu_adjust_nmi_window(int handled)
866 {
867 	/*
868 	 * If a counter was handled, record a timestamp such that un-handled
869 	 * NMIs will be claimed if arriving within that window.
870 	 */
871 	if (handled) {
872 		this_cpu_write(perf_nmi_tstamp, jiffies + perf_nmi_window);
873 
874 		return handled;
875 	}
876 
877 	if (time_after(jiffies, this_cpu_read(perf_nmi_tstamp)))
878 		return NMI_DONE;
879 
880 	return NMI_HANDLED;
881 }
882 
883 static int amd_pmu_handle_irq(struct pt_regs *regs)
884 {
885 	struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events);
886 	int handled;
887 	int pmu_enabled;
888 
889 	/*
890 	 * Save the PMU state.
891 	 * It needs to be restored when leaving the handler.
892 	 */
893 	pmu_enabled = cpuc->enabled;
894 	cpuc->enabled = 0;
895 
896 	amd_brs_disable_all();
897 
898 	/* Drain BRS is in use (could be inactive) */
899 	if (cpuc->lbr_users)
900 		amd_brs_drain();
901 
902 	/* Process any counter overflows */
903 	handled = x86_pmu_handle_irq(regs);
904 
905 	cpuc->enabled = pmu_enabled;
906 	if (pmu_enabled)
907 		amd_brs_enable_all();
908 
909 	return amd_pmu_adjust_nmi_window(handled);
910 }
911 
912 /*
913  * AMD-specific callback invoked through perf_snapshot_branch_stack static
914  * call, defined in include/linux/perf_event.h. See its definition for API
915  * details. It's up to caller to provide enough space in *entries* to fit all
916  * LBR records, otherwise returned result will be truncated to *cnt* entries.
917  */
918 static int amd_pmu_v2_snapshot_branch_stack(struct perf_branch_entry *entries, unsigned int cnt)
919 {
920 	struct cpu_hw_events *cpuc;
921 	unsigned long flags;
922 
923 	/*
924 	 * The sequence of steps to freeze LBR should be completely inlined
925 	 * and contain no branches to minimize contamination of LBR snapshot
926 	 */
927 	local_irq_save(flags);
928 	amd_pmu_core_disable_all();
929 	__amd_pmu_lbr_disable();
930 
931 	cpuc = this_cpu_ptr(&cpu_hw_events);
932 
933 	amd_pmu_lbr_read();
934 	cnt = min(cnt, x86_pmu.lbr_nr);
935 	memcpy(entries, cpuc->lbr_entries, sizeof(struct perf_branch_entry) * cnt);
936 
937 	amd_pmu_v2_enable_all(0);
938 	local_irq_restore(flags);
939 
940 	return cnt;
941 }
942 
943 static int amd_pmu_v2_handle_irq(struct pt_regs *regs)
944 {
945 	struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events);
946 	struct perf_sample_data data;
947 	struct hw_perf_event *hwc;
948 	struct perf_event *event;
949 	int handled = 0, idx;
950 	u64 reserved, status, mask;
951 	bool pmu_enabled;
952 
953 	/*
954 	 * Save the PMU state as it needs to be restored when leaving the
955 	 * handler
956 	 */
957 	pmu_enabled = cpuc->enabled;
958 	cpuc->enabled = 0;
959 
960 	/* Stop counting but do not disable LBR */
961 	amd_pmu_core_disable_all();
962 
963 	status = amd_pmu_get_global_status();
964 
965 	/* Check if any overflows are pending */
966 	if (!status)
967 		goto done;
968 
969 	/* Read branch records */
970 	if (x86_pmu.lbr_nr) {
971 		amd_pmu_lbr_read();
972 		status &= ~GLOBAL_STATUS_LBRS_FROZEN;
973 	}
974 
975 	reserved = status & ~amd_pmu_global_cntr_mask;
976 	if (reserved)
977 		pr_warn_once("Reserved PerfCntrGlobalStatus bits are set (0x%llx), please consider updating microcode\n",
978 			     reserved);
979 
980 	/* Clear any reserved bits set by buggy microcode */
981 	status &= amd_pmu_global_cntr_mask;
982 
983 	for_each_set_bit(idx, x86_pmu.cntr_mask, X86_PMC_IDX_MAX) {
984 		if (!test_bit(idx, cpuc->active_mask))
985 			continue;
986 
987 		event = cpuc->events[idx];
988 		hwc = &event->hw;
989 		x86_perf_event_update(event);
990 		mask = BIT_ULL(idx);
991 
992 		if (!(status & mask))
993 			continue;
994 
995 		/* Event overflow */
996 		handled++;
997 		status &= ~mask;
998 		perf_sample_data_init(&data, 0, hwc->last_period);
999 
1000 		if (!x86_perf_event_set_period(event))
1001 			continue;
1002 
1003 		if (has_branch_stack(event))
1004 			perf_sample_save_brstack(&data, event, &cpuc->lbr_stack, NULL);
1005 
1006 		if (perf_event_overflow(event, &data, regs))
1007 			x86_pmu_stop(event, 0);
1008 	}
1009 
1010 	/*
1011 	 * It should never be the case that some overflows are not handled as
1012 	 * the corresponding PMCs are expected to be inactive according to the
1013 	 * active_mask
1014 	 */
1015 	WARN_ON(status > 0);
1016 
1017 	/* Clear overflow and freeze bits */
1018 	amd_pmu_ack_global_status(~status);
1019 
1020 	/*
1021 	 * Unmasking the LVTPC is not required as the Mask (M) bit of the LVT
1022 	 * PMI entry is not set by the local APIC when a PMC overflow occurs
1023 	 */
1024 	inc_irq_stat(apic_perf_irqs);
1025 
1026 done:
1027 	cpuc->enabled = pmu_enabled;
1028 
1029 	/* Resume counting only if PMU is active */
1030 	if (pmu_enabled)
1031 		amd_pmu_core_enable_all();
1032 
1033 	return amd_pmu_adjust_nmi_window(handled);
1034 }
1035 
1036 static struct event_constraint *
1037 amd_get_event_constraints(struct cpu_hw_events *cpuc, int idx,
1038 			  struct perf_event *event)
1039 {
1040 	/*
1041 	 * if not NB event or no NB, then no constraints
1042 	 */
1043 	if (!(amd_has_nb(cpuc) && amd_is_nb_event(&event->hw)))
1044 		return &unconstrained;
1045 
1046 	return __amd_get_nb_event_constraints(cpuc, event, NULL);
1047 }
1048 
1049 static void amd_put_event_constraints(struct cpu_hw_events *cpuc,
1050 				      struct perf_event *event)
1051 {
1052 	if (amd_has_nb(cpuc) && amd_is_nb_event(&event->hw))
1053 		__amd_put_nb_event_constraints(cpuc, event);
1054 }
1055 
1056 PMU_FORMAT_ATTR(event,	"config:0-7,32-35");
1057 PMU_FORMAT_ATTR(umask,	"config:8-15"	);
1058 PMU_FORMAT_ATTR(edge,	"config:18"	);
1059 PMU_FORMAT_ATTR(inv,	"config:23"	);
1060 PMU_FORMAT_ATTR(cmask,	"config:24-31"	);
1061 
1062 static struct attribute *amd_format_attr[] = {
1063 	&format_attr_event.attr,
1064 	&format_attr_umask.attr,
1065 	&format_attr_edge.attr,
1066 	&format_attr_inv.attr,
1067 	&format_attr_cmask.attr,
1068 	NULL,
1069 };
1070 
1071 /* AMD Family 15h */
1072 
1073 #define AMD_EVENT_TYPE_MASK	0x000000F0ULL
1074 
1075 #define AMD_EVENT_FP		0x00000000ULL ... 0x00000010ULL
1076 #define AMD_EVENT_LS		0x00000020ULL ... 0x00000030ULL
1077 #define AMD_EVENT_DC		0x00000040ULL ... 0x00000050ULL
1078 #define AMD_EVENT_CU		0x00000060ULL ... 0x00000070ULL
1079 #define AMD_EVENT_IC_DE		0x00000080ULL ... 0x00000090ULL
1080 #define AMD_EVENT_EX_LS		0x000000C0ULL
1081 #define AMD_EVENT_DE		0x000000D0ULL
1082 #define AMD_EVENT_NB		0x000000E0ULL ... 0x000000F0ULL
1083 
1084 /*
1085  * AMD family 15h event code/PMC mappings:
1086  *
1087  * type = event_code & 0x0F0:
1088  *
1089  * 0x000	FP	PERF_CTL[5:3]
1090  * 0x010	FP	PERF_CTL[5:3]
1091  * 0x020	LS	PERF_CTL[5:0]
1092  * 0x030	LS	PERF_CTL[5:0]
1093  * 0x040	DC	PERF_CTL[5:0]
1094  * 0x050	DC	PERF_CTL[5:0]
1095  * 0x060	CU	PERF_CTL[2:0]
1096  * 0x070	CU	PERF_CTL[2:0]
1097  * 0x080	IC/DE	PERF_CTL[2:0]
1098  * 0x090	IC/DE	PERF_CTL[2:0]
1099  * 0x0A0	---
1100  * 0x0B0	---
1101  * 0x0C0	EX/LS	PERF_CTL[5:0]
1102  * 0x0D0	DE	PERF_CTL[2:0]
1103  * 0x0E0	NB	NB_PERF_CTL[3:0]
1104  * 0x0F0	NB	NB_PERF_CTL[3:0]
1105  *
1106  * Exceptions:
1107  *
1108  * 0x000	FP	PERF_CTL[3], PERF_CTL[5:3] (*)
1109  * 0x003	FP	PERF_CTL[3]
1110  * 0x004	FP	PERF_CTL[3], PERF_CTL[5:3] (*)
1111  * 0x00B	FP	PERF_CTL[3]
1112  * 0x00D	FP	PERF_CTL[3]
1113  * 0x023	DE	PERF_CTL[2:0]
1114  * 0x02D	LS	PERF_CTL[3]
1115  * 0x02E	LS	PERF_CTL[3,0]
1116  * 0x031	LS	PERF_CTL[2:0] (**)
1117  * 0x043	CU	PERF_CTL[2:0]
1118  * 0x045	CU	PERF_CTL[2:0]
1119  * 0x046	CU	PERF_CTL[2:0]
1120  * 0x054	CU	PERF_CTL[2:0]
1121  * 0x055	CU	PERF_CTL[2:0]
1122  * 0x08F	IC	PERF_CTL[0]
1123  * 0x187	DE	PERF_CTL[0]
1124  * 0x188	DE	PERF_CTL[0]
1125  * 0x0DB	EX	PERF_CTL[5:0]
1126  * 0x0DC	LS	PERF_CTL[5:0]
1127  * 0x0DD	LS	PERF_CTL[5:0]
1128  * 0x0DE	LS	PERF_CTL[5:0]
1129  * 0x0DF	LS	PERF_CTL[5:0]
1130  * 0x1C0	EX	PERF_CTL[5:3]
1131  * 0x1D6	EX	PERF_CTL[5:0]
1132  * 0x1D8	EX	PERF_CTL[5:0]
1133  *
1134  * (*)  depending on the umask all FPU counters may be used
1135  * (**) only one unitmask enabled at a time
1136  */
1137 
1138 static struct event_constraint amd_f15_PMC0  = EVENT_CONSTRAINT(0, 0x01, 0);
1139 static struct event_constraint amd_f15_PMC20 = EVENT_CONSTRAINT(0, 0x07, 0);
1140 static struct event_constraint amd_f15_PMC3  = EVENT_CONSTRAINT(0, 0x08, 0);
1141 static struct event_constraint amd_f15_PMC30 = EVENT_CONSTRAINT_OVERLAP(0, 0x09, 0);
1142 static struct event_constraint amd_f15_PMC50 = EVENT_CONSTRAINT(0, 0x3F, 0);
1143 static struct event_constraint amd_f15_PMC53 = EVENT_CONSTRAINT(0, 0x38, 0);
1144 
1145 static struct event_constraint *
1146 amd_get_event_constraints_f15h(struct cpu_hw_events *cpuc, int idx,
1147 			       struct perf_event *event)
1148 {
1149 	struct hw_perf_event *hwc = &event->hw;
1150 	unsigned int event_code = amd_get_event_code(hwc);
1151 
1152 	switch (event_code & AMD_EVENT_TYPE_MASK) {
1153 	case AMD_EVENT_FP:
1154 		switch (event_code) {
1155 		case 0x000:
1156 			if (!(hwc->config & 0x0000F000ULL))
1157 				break;
1158 			if (!(hwc->config & 0x00000F00ULL))
1159 				break;
1160 			return &amd_f15_PMC3;
1161 		case 0x004:
1162 			if (hweight_long(hwc->config & ARCH_PERFMON_EVENTSEL_UMASK) <= 1)
1163 				break;
1164 			return &amd_f15_PMC3;
1165 		case 0x003:
1166 		case 0x00B:
1167 		case 0x00D:
1168 			return &amd_f15_PMC3;
1169 		}
1170 		return &amd_f15_PMC53;
1171 	case AMD_EVENT_LS:
1172 	case AMD_EVENT_DC:
1173 	case AMD_EVENT_EX_LS:
1174 		switch (event_code) {
1175 		case 0x023:
1176 		case 0x043:
1177 		case 0x045:
1178 		case 0x046:
1179 		case 0x054:
1180 		case 0x055:
1181 			return &amd_f15_PMC20;
1182 		case 0x02D:
1183 			return &amd_f15_PMC3;
1184 		case 0x02E:
1185 			return &amd_f15_PMC30;
1186 		case 0x031:
1187 			if (hweight_long(hwc->config & ARCH_PERFMON_EVENTSEL_UMASK) <= 1)
1188 				return &amd_f15_PMC20;
1189 			return &emptyconstraint;
1190 		case 0x1C0:
1191 			return &amd_f15_PMC53;
1192 		default:
1193 			return &amd_f15_PMC50;
1194 		}
1195 	case AMD_EVENT_CU:
1196 	case AMD_EVENT_IC_DE:
1197 	case AMD_EVENT_DE:
1198 		switch (event_code) {
1199 		case 0x08F:
1200 		case 0x187:
1201 		case 0x188:
1202 			return &amd_f15_PMC0;
1203 		case 0x0DB ... 0x0DF:
1204 		case 0x1D6:
1205 		case 0x1D8:
1206 			return &amd_f15_PMC50;
1207 		default:
1208 			return &amd_f15_PMC20;
1209 		}
1210 	case AMD_EVENT_NB:
1211 		/* moved to uncore.c */
1212 		return &emptyconstraint;
1213 	default:
1214 		return &emptyconstraint;
1215 	}
1216 }
1217 
1218 static struct event_constraint pair_constraint;
1219 
1220 static struct event_constraint *
1221 amd_get_event_constraints_f17h(struct cpu_hw_events *cpuc, int idx,
1222 			       struct perf_event *event)
1223 {
1224 	struct hw_perf_event *hwc = &event->hw;
1225 
1226 	if (amd_is_pair_event_code(hwc))
1227 		return &pair_constraint;
1228 
1229 	return &unconstrained;
1230 }
1231 
1232 static void amd_put_event_constraints_f17h(struct cpu_hw_events *cpuc,
1233 					   struct perf_event *event)
1234 {
1235 	struct hw_perf_event *hwc = &event->hw;
1236 
1237 	if (is_counter_pair(hwc))
1238 		--cpuc->n_pair;
1239 }
1240 
1241 /*
1242  * Because of the way BRS operates with an inactive and active phases, and
1243  * the link to one counter, it is not possible to have two events using BRS
1244  * scheduled at the same time. There would be an issue with enforcing the
1245  * period of each one and given that the BRS saturates, it would not be possible
1246  * to guarantee correlated content for all events. Therefore, in situations
1247  * where multiple events want to use BRS, the kernel enforces mutual exclusion.
1248  * Exclusion is enforced by choosing only one counter for events using BRS.
1249  * The event scheduling logic will then automatically multiplex the
1250  * events and ensure that at most one event is actively using BRS.
1251  *
1252  * The BRS counter could be any counter, but there is no constraint on Fam19h,
1253  * therefore all counters are equal and thus we pick the first one: PMC0
1254  */
1255 static struct event_constraint amd_fam19h_brs_cntr0_constraint =
1256 	EVENT_CONSTRAINT(0, 0x1, AMD64_RAW_EVENT_MASK);
1257 
1258 static struct event_constraint amd_fam19h_brs_pair_cntr0_constraint =
1259 	__EVENT_CONSTRAINT(0, 0x1, AMD64_RAW_EVENT_MASK, 1, 0, PERF_X86_EVENT_PAIR);
1260 
1261 static struct event_constraint *
1262 amd_get_event_constraints_f19h(struct cpu_hw_events *cpuc, int idx,
1263 			  struct perf_event *event)
1264 {
1265 	struct hw_perf_event *hwc = &event->hw;
1266 	bool has_brs = has_amd_brs(hwc);
1267 
1268 	/*
1269 	 * In case BRS is used with an event requiring a counter pair,
1270 	 * the kernel allows it but only on counter 0 & 1 to enforce
1271 	 * multiplexing requiring to protect BRS in case of multiple
1272 	 * BRS users
1273 	 */
1274 	if (amd_is_pair_event_code(hwc)) {
1275 		return has_brs ? &amd_fam19h_brs_pair_cntr0_constraint
1276 			       : &pair_constraint;
1277 	}
1278 
1279 	if (has_brs)
1280 		return &amd_fam19h_brs_cntr0_constraint;
1281 
1282 	return &unconstrained;
1283 }
1284 
1285 
1286 static ssize_t amd_event_sysfs_show(char *page, u64 config)
1287 {
1288 	u64 event = (config & ARCH_PERFMON_EVENTSEL_EVENT) |
1289 		    (config & AMD64_EVENTSEL_EVENT) >> 24;
1290 
1291 	return x86_event_sysfs_show(page, config, event);
1292 }
1293 
1294 static void amd_pmu_limit_period(struct perf_event *event, s64 *left)
1295 {
1296 	/*
1297 	 * Decrease period by the depth of the BRS feature to get the last N
1298 	 * taken branches and approximate the desired period
1299 	 */
1300 	if (has_branch_stack(event) && *left > x86_pmu.lbr_nr)
1301 		*left -= x86_pmu.lbr_nr;
1302 }
1303 
1304 static __initconst const struct x86_pmu amd_pmu = {
1305 	.name			= "AMD",
1306 	.handle_irq		= amd_pmu_handle_irq,
1307 	.disable_all		= amd_pmu_disable_all,
1308 	.enable_all		= amd_pmu_enable_all,
1309 	.enable			= amd_pmu_enable_event,
1310 	.disable		= amd_pmu_disable_event,
1311 	.hw_config		= amd_pmu_hw_config,
1312 	.schedule_events	= x86_schedule_events,
1313 	.eventsel		= MSR_K7_EVNTSEL0,
1314 	.perfctr		= MSR_K7_PERFCTR0,
1315 	.addr_offset            = amd_pmu_addr_offset,
1316 	.event_map		= amd_pmu_event_map,
1317 	.max_events		= ARRAY_SIZE(amd_perfmon_event_map),
1318 	.cntr_mask64		= GENMASK_ULL(AMD64_NUM_COUNTERS - 1, 0),
1319 	.add			= amd_pmu_add_event,
1320 	.del			= amd_pmu_del_event,
1321 	.cntval_bits		= 48,
1322 	.cntval_mask		= (1ULL << 48) - 1,
1323 	.apic			= 1,
1324 	/* use highest bit to detect overflow */
1325 	.max_period		= (1ULL << 47) - 1,
1326 	.get_event_constraints	= amd_get_event_constraints,
1327 	.put_event_constraints	= amd_put_event_constraints,
1328 
1329 	.format_attrs		= amd_format_attr,
1330 	.events_sysfs_show	= amd_event_sysfs_show,
1331 
1332 	.cpu_prepare		= amd_pmu_cpu_prepare,
1333 	.cpu_starting		= amd_pmu_cpu_starting,
1334 	.cpu_dead		= amd_pmu_cpu_dead,
1335 
1336 	.amd_nb_constraints	= 1,
1337 };
1338 
1339 static ssize_t branches_show(struct device *cdev,
1340 			      struct device_attribute *attr,
1341 			      char *buf)
1342 {
1343 	return snprintf(buf, PAGE_SIZE, "%d\n", x86_pmu.lbr_nr);
1344 }
1345 
1346 static DEVICE_ATTR_RO(branches);
1347 
1348 static struct attribute *amd_pmu_branches_attrs[] = {
1349 	&dev_attr_branches.attr,
1350 	NULL,
1351 };
1352 
1353 static umode_t
1354 amd_branches_is_visible(struct kobject *kobj, struct attribute *attr, int i)
1355 {
1356 	return x86_pmu.lbr_nr ? attr->mode : 0;
1357 }
1358 
1359 static struct attribute_group group_caps_amd_branches = {
1360 	.name  = "caps",
1361 	.attrs = amd_pmu_branches_attrs,
1362 	.is_visible = amd_branches_is_visible,
1363 };
1364 
1365 #ifdef CONFIG_PERF_EVENTS_AMD_BRS
1366 
1367 EVENT_ATTR_STR(branch-brs, amd_branch_brs,
1368 	       "event=" __stringify(AMD_FAM19H_BRS_EVENT)"\n");
1369 
1370 static struct attribute *amd_brs_events_attrs[] = {
1371 	EVENT_PTR(amd_branch_brs),
1372 	NULL,
1373 };
1374 
1375 static umode_t
1376 amd_brs_is_visible(struct kobject *kobj, struct attribute *attr, int i)
1377 {
1378 	return static_cpu_has(X86_FEATURE_BRS) && x86_pmu.lbr_nr ?
1379 	       attr->mode : 0;
1380 }
1381 
1382 static struct attribute_group group_events_amd_brs = {
1383 	.name       = "events",
1384 	.attrs      = amd_brs_events_attrs,
1385 	.is_visible = amd_brs_is_visible,
1386 };
1387 
1388 #endif	/* CONFIG_PERF_EVENTS_AMD_BRS */
1389 
1390 static const struct attribute_group *amd_attr_update[] = {
1391 	&group_caps_amd_branches,
1392 #ifdef CONFIG_PERF_EVENTS_AMD_BRS
1393 	&group_events_amd_brs,
1394 #endif
1395 	NULL,
1396 };
1397 
1398 static int __init amd_core_pmu_init(void)
1399 {
1400 	union cpuid_0x80000022_ebx ebx;
1401 	u64 even_ctr_mask = 0ULL;
1402 	int i;
1403 
1404 	if (!boot_cpu_has(X86_FEATURE_PERFCTR_CORE))
1405 		return 0;
1406 
1407 	/* Avoid calculating the value each time in the NMI handler */
1408 	perf_nmi_window = msecs_to_jiffies(100);
1409 
1410 	/*
1411 	 * If core performance counter extensions exists, we must use
1412 	 * MSR_F15H_PERF_CTL/MSR_F15H_PERF_CTR msrs. See also
1413 	 * amd_pmu_addr_offset().
1414 	 */
1415 	x86_pmu.eventsel	= MSR_F15H_PERF_CTL;
1416 	x86_pmu.perfctr		= MSR_F15H_PERF_CTR;
1417 	x86_pmu.cntr_mask64	= GENMASK_ULL(AMD64_NUM_COUNTERS_CORE - 1, 0);
1418 
1419 	/* Check for Performance Monitoring v2 support */
1420 	if (boot_cpu_has(X86_FEATURE_PERFMON_V2)) {
1421 		ebx.full = cpuid_ebx(EXT_PERFMON_DEBUG_FEATURES);
1422 
1423 		/* Update PMU version for later usage */
1424 		x86_pmu.version = 2;
1425 
1426 		/* Find the number of available Core PMCs */
1427 		x86_pmu.cntr_mask64 = GENMASK_ULL(ebx.split.num_core_pmc - 1, 0);
1428 
1429 		amd_pmu_global_cntr_mask = x86_pmu.cntr_mask64;
1430 
1431 		/* Update PMC handling functions */
1432 		x86_pmu.enable_all = amd_pmu_v2_enable_all;
1433 		x86_pmu.disable_all = amd_pmu_v2_disable_all;
1434 		x86_pmu.enable = amd_pmu_v2_enable_event;
1435 		x86_pmu.handle_irq = amd_pmu_v2_handle_irq;
1436 		static_call_update(amd_pmu_test_overflow, amd_pmu_test_overflow_status);
1437 	}
1438 
1439 	/*
1440 	 * AMD Core perfctr has separate MSRs for the NB events, see
1441 	 * the amd/uncore.c driver.
1442 	 */
1443 	x86_pmu.amd_nb_constraints = 0;
1444 
1445 	if (boot_cpu_data.x86 == 0x15) {
1446 		pr_cont("Fam15h ");
1447 		x86_pmu.get_event_constraints = amd_get_event_constraints_f15h;
1448 	}
1449 	if (boot_cpu_data.x86 >= 0x17) {
1450 		pr_cont("Fam17h+ ");
1451 		/*
1452 		 * Family 17h and compatibles have constraints for Large
1453 		 * Increment per Cycle events: they may only be assigned an
1454 		 * even numbered counter that has a consecutive adjacent odd
1455 		 * numbered counter following it.
1456 		 */
1457 		for (i = 0; i < x86_pmu_max_num_counters(NULL) - 1; i += 2)
1458 			even_ctr_mask |= BIT_ULL(i);
1459 
1460 		pair_constraint = (struct event_constraint)
1461 				    __EVENT_CONSTRAINT(0, even_ctr_mask, 0,
1462 				    x86_pmu_max_num_counters(NULL) / 2, 0,
1463 				    PERF_X86_EVENT_PAIR);
1464 
1465 		x86_pmu.get_event_constraints = amd_get_event_constraints_f17h;
1466 		x86_pmu.put_event_constraints = amd_put_event_constraints_f17h;
1467 		x86_pmu.perf_ctr_pair_en = AMD_MERGE_EVENT_ENABLE;
1468 		x86_pmu.flags |= PMU_FL_PAIR;
1469 	}
1470 
1471 	/* LBR and BRS are mutually exclusive features */
1472 	if (!amd_pmu_lbr_init()) {
1473 		/* LBR requires flushing on context switch */
1474 		x86_pmu.sched_task = amd_pmu_lbr_sched_task;
1475 		static_call_update(amd_pmu_branch_hw_config, amd_pmu_lbr_hw_config);
1476 		static_call_update(amd_pmu_branch_reset, amd_pmu_lbr_reset);
1477 		static_call_update(amd_pmu_branch_add, amd_pmu_lbr_add);
1478 		static_call_update(amd_pmu_branch_del, amd_pmu_lbr_del);
1479 
1480 		/* Only support branch_stack snapshot on perfmon v2 */
1481 		if (x86_pmu.handle_irq == amd_pmu_v2_handle_irq)
1482 			static_call_update(perf_snapshot_branch_stack, amd_pmu_v2_snapshot_branch_stack);
1483 	} else if (!amd_brs_init()) {
1484 		/*
1485 		 * BRS requires special event constraints and flushing on ctxsw.
1486 		 */
1487 		x86_pmu.get_event_constraints = amd_get_event_constraints_f19h;
1488 		x86_pmu.sched_task = amd_pmu_brs_sched_task;
1489 		x86_pmu.limit_period = amd_pmu_limit_period;
1490 
1491 		static_call_update(amd_pmu_branch_hw_config, amd_brs_hw_config);
1492 		static_call_update(amd_pmu_branch_reset, amd_brs_reset);
1493 		static_call_update(amd_pmu_branch_add, amd_pmu_brs_add);
1494 		static_call_update(amd_pmu_branch_del, amd_pmu_brs_del);
1495 
1496 		/*
1497 		 * put_event_constraints callback same as Fam17h, set above
1498 		 */
1499 
1500 		/* branch sampling must be stopped when entering low power */
1501 		amd_brs_lopwr_init();
1502 	}
1503 
1504 	x86_pmu.attr_update = amd_attr_update;
1505 
1506 	pr_cont("core perfctr, ");
1507 	return 0;
1508 }
1509 
1510 __init int amd_pmu_init(void)
1511 {
1512 	int ret;
1513 
1514 	/* Performance-monitoring supported from K7 and later: */
1515 	if (boot_cpu_data.x86 < 6)
1516 		return -ENODEV;
1517 
1518 	x86_pmu = amd_pmu;
1519 
1520 	ret = amd_core_pmu_init();
1521 	if (ret)
1522 		return ret;
1523 
1524 	if (num_possible_cpus() == 1) {
1525 		/*
1526 		 * No point in allocating data structures to serialize
1527 		 * against other CPUs, when there is only the one CPU.
1528 		 */
1529 		x86_pmu.amd_nb_constraints = 0;
1530 	}
1531 
1532 	if (boot_cpu_data.x86 >= 0x17)
1533 		memcpy(hw_cache_event_ids, amd_hw_cache_event_ids_f17h, sizeof(hw_cache_event_ids));
1534 	else
1535 		memcpy(hw_cache_event_ids, amd_hw_cache_event_ids, sizeof(hw_cache_event_ids));
1536 
1537 	return 0;
1538 }
1539 
1540 static inline void amd_pmu_reload_virt(void)
1541 {
1542 	if (x86_pmu.version >= 2) {
1543 		/*
1544 		 * Clear global enable bits, reprogram the PERF_CTL
1545 		 * registers with updated perf_ctr_virt_mask and then
1546 		 * set global enable bits once again
1547 		 */
1548 		amd_pmu_v2_disable_all();
1549 		amd_pmu_enable_all(0);
1550 		amd_pmu_v2_enable_all(0);
1551 		return;
1552 	}
1553 
1554 	amd_pmu_disable_all();
1555 	amd_pmu_enable_all(0);
1556 }
1557 
1558 void amd_pmu_enable_virt(void)
1559 {
1560 	struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events);
1561 
1562 	cpuc->perf_ctr_virt_mask = 0;
1563 
1564 	/* Reload all events */
1565 	amd_pmu_reload_virt();
1566 }
1567 EXPORT_SYMBOL_GPL(amd_pmu_enable_virt);
1568 
1569 void amd_pmu_disable_virt(void)
1570 {
1571 	struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events);
1572 
1573 	/*
1574 	 * We only mask out the Host-only bit so that host-only counting works
1575 	 * when SVM is disabled. If someone sets up a guest-only counter when
1576 	 * SVM is disabled the Guest-only bits still gets set and the counter
1577 	 * will not count anything.
1578 	 */
1579 	cpuc->perf_ctr_virt_mask = AMD64_EVENTSEL_HOSTONLY;
1580 
1581 	/* Reload all events */
1582 	amd_pmu_reload_virt();
1583 }
1584 EXPORT_SYMBOL_GPL(amd_pmu_disable_virt);
1585