xref: /openbmc/linux/arch/x86/events/amd/ibs.c (revision 8bfc20ba)
1 /*
2  * Performance events - AMD IBS
3  *
4  *  Copyright (C) 2011 Advanced Micro Devices, Inc., Robert Richter
5  *
6  *  For licencing details see kernel-base/COPYING
7  */
8 
9 #include <linux/perf_event.h>
10 #include <linux/init.h>
11 #include <linux/export.h>
12 #include <linux/pci.h>
13 #include <linux/ptrace.h>
14 #include <linux/syscore_ops.h>
15 #include <linux/sched/clock.h>
16 
17 #include <asm/apic.h>
18 
19 #include "../perf_event.h"
20 
21 static u32 ibs_caps;
22 
23 #if defined(CONFIG_PERF_EVENTS) && defined(CONFIG_CPU_SUP_AMD)
24 
25 #include <linux/kprobes.h>
26 #include <linux/hardirq.h>
27 
28 #include <asm/nmi.h>
29 #include <asm/amd-ibs.h>
30 
31 #define IBS_FETCH_CONFIG_MASK	(IBS_FETCH_RAND_EN | IBS_FETCH_MAX_CNT)
32 #define IBS_OP_CONFIG_MASK	IBS_OP_MAX_CNT
33 
34 
35 /*
36  * IBS states:
37  *
38  * ENABLED; tracks the pmu::add(), pmu::del() state, when set the counter is taken
39  * and any further add()s must fail.
40  *
41  * STARTED/STOPPING/STOPPED; deal with pmu::start(), pmu::stop() state but are
42  * complicated by the fact that the IBS hardware can send late NMIs (ie. after
43  * we've cleared the EN bit).
44  *
45  * In order to consume these late NMIs we have the STOPPED state, any NMI that
46  * happens after we've cleared the EN state will clear this bit and report the
47  * NMI handled (this is fundamentally racy in the face or multiple NMI sources,
48  * someone else can consume our BIT and our NMI will go unhandled).
49  *
50  * And since we cannot set/clear this separate bit together with the EN bit,
51  * there are races; if we cleared STARTED early, an NMI could land in
52  * between clearing STARTED and clearing the EN bit (in fact multiple NMIs
53  * could happen if the period is small enough), and consume our STOPPED bit
54  * and trigger streams of unhandled NMIs.
55  *
56  * If, however, we clear STARTED late, an NMI can hit between clearing the
57  * EN bit and clearing STARTED, still see STARTED set and process the event.
58  * If this event will have the VALID bit clear, we bail properly, but this
59  * is not a given. With VALID set we can end up calling pmu::stop() again
60  * (the throttle logic) and trigger the WARNs in there.
61  *
62  * So what we do is set STOPPING before clearing EN to avoid the pmu::stop()
63  * nesting, and clear STARTED late, so that we have a well defined state over
64  * the clearing of the EN bit.
65  *
66  * XXX: we could probably be using !atomic bitops for all this.
67  */
68 
69 enum ibs_states {
70 	IBS_ENABLED	= 0,
71 	IBS_STARTED	= 1,
72 	IBS_STOPPING	= 2,
73 	IBS_STOPPED	= 3,
74 
75 	IBS_MAX_STATES,
76 };
77 
78 struct cpu_perf_ibs {
79 	struct perf_event	*event;
80 	unsigned long		state[BITS_TO_LONGS(IBS_MAX_STATES)];
81 };
82 
83 struct perf_ibs {
84 	struct pmu			pmu;
85 	unsigned int			msr;
86 	u64				config_mask;
87 	u64				cnt_mask;
88 	u64				enable_mask;
89 	u64				valid_mask;
90 	u64				max_period;
91 	unsigned long			offset_mask[1];
92 	int				offset_max;
93 	unsigned int			fetch_count_reset_broken : 1;
94 	unsigned int			fetch_ignore_if_zero_rip : 1;
95 	struct cpu_perf_ibs __percpu	*pcpu;
96 
97 	u64				(*get_count)(u64 config);
98 };
99 
100 static int
perf_event_set_period(struct hw_perf_event * hwc,u64 min,u64 max,u64 * hw_period)101 perf_event_set_period(struct hw_perf_event *hwc, u64 min, u64 max, u64 *hw_period)
102 {
103 	s64 left = local64_read(&hwc->period_left);
104 	s64 period = hwc->sample_period;
105 	int overflow = 0;
106 
107 	/*
108 	 * If we are way outside a reasonable range then just skip forward:
109 	 */
110 	if (unlikely(left <= -period)) {
111 		left = period;
112 		local64_set(&hwc->period_left, left);
113 		hwc->last_period = period;
114 		overflow = 1;
115 	}
116 
117 	if (unlikely(left < (s64)min)) {
118 		left += period;
119 		local64_set(&hwc->period_left, left);
120 		hwc->last_period = period;
121 		overflow = 1;
122 	}
123 
124 	/*
125 	 * If the hw period that triggers the sw overflow is too short
126 	 * we might hit the irq handler. This biases the results.
127 	 * Thus we shorten the next-to-last period and set the last
128 	 * period to the max period.
129 	 */
130 	if (left > max) {
131 		left -= max;
132 		if (left > max)
133 			left = max;
134 		else if (left < min)
135 			left = min;
136 	}
137 
138 	*hw_period = (u64)left;
139 
140 	return overflow;
141 }
142 
143 static  int
perf_event_try_update(struct perf_event * event,u64 new_raw_count,int width)144 perf_event_try_update(struct perf_event *event, u64 new_raw_count, int width)
145 {
146 	struct hw_perf_event *hwc = &event->hw;
147 	int shift = 64 - width;
148 	u64 prev_raw_count;
149 	u64 delta;
150 
151 	/*
152 	 * Careful: an NMI might modify the previous event value.
153 	 *
154 	 * Our tactic to handle this is to first atomically read and
155 	 * exchange a new raw count - then add that new-prev delta
156 	 * count to the generic event atomically:
157 	 */
158 	prev_raw_count = local64_read(&hwc->prev_count);
159 	if (!local64_try_cmpxchg(&hwc->prev_count,
160 				 &prev_raw_count, new_raw_count))
161 		return 0;
162 
163 	/*
164 	 * Now we have the new raw value and have updated the prev
165 	 * timestamp already. We can now calculate the elapsed delta
166 	 * (event-)time and add that to the generic event.
167 	 *
168 	 * Careful, not all hw sign-extends above the physical width
169 	 * of the count.
170 	 */
171 	delta = (new_raw_count << shift) - (prev_raw_count << shift);
172 	delta >>= shift;
173 
174 	local64_add(delta, &event->count);
175 	local64_sub(delta, &hwc->period_left);
176 
177 	return 1;
178 }
179 
180 static struct perf_ibs perf_ibs_fetch;
181 static struct perf_ibs perf_ibs_op;
182 
get_ibs_pmu(int type)183 static struct perf_ibs *get_ibs_pmu(int type)
184 {
185 	if (perf_ibs_fetch.pmu.type == type)
186 		return &perf_ibs_fetch;
187 	if (perf_ibs_op.pmu.type == type)
188 		return &perf_ibs_op;
189 	return NULL;
190 }
191 
192 /*
193  * core pmu config -> IBS config
194  *
195  *  perf record -a -e cpu-cycles:p ...    # use ibs op counting cycle count
196  *  perf record -a -e r076:p ...          # same as -e cpu-cycles:p
197  *  perf record -a -e r0C1:p ...          # use ibs op counting micro-ops
198  *
199  * IbsOpCntCtl (bit 19) of IBS Execution Control Register (IbsOpCtl,
200  * MSRC001_1033) is used to select either cycle or micro-ops counting
201  * mode.
202  */
core_pmu_ibs_config(struct perf_event * event,u64 * config)203 static int core_pmu_ibs_config(struct perf_event *event, u64 *config)
204 {
205 	switch (event->attr.type) {
206 	case PERF_TYPE_HARDWARE:
207 		switch (event->attr.config) {
208 		case PERF_COUNT_HW_CPU_CYCLES:
209 			*config = 0;
210 			return 0;
211 		}
212 		break;
213 	case PERF_TYPE_RAW:
214 		switch (event->attr.config) {
215 		case 0x0076:
216 			*config = 0;
217 			return 0;
218 		case 0x00C1:
219 			*config = IBS_OP_CNT_CTL;
220 			return 0;
221 		}
222 		break;
223 	default:
224 		return -ENOENT;
225 	}
226 
227 	return -EOPNOTSUPP;
228 }
229 
230 /*
231  * The rip of IBS samples has skid 0. Thus, IBS supports precise
232  * levels 1 and 2 and the PERF_EFLAGS_EXACT is set. In rare cases the
233  * rip is invalid when IBS was not able to record the rip correctly.
234  * We clear PERF_EFLAGS_EXACT and take the rip from pt_regs then.
235  */
forward_event_to_ibs(struct perf_event * event)236 int forward_event_to_ibs(struct perf_event *event)
237 {
238 	u64 config = 0;
239 
240 	if (!event->attr.precise_ip || event->attr.precise_ip > 2)
241 		return -EOPNOTSUPP;
242 
243 	if (!core_pmu_ibs_config(event, &config)) {
244 		event->attr.type = perf_ibs_op.pmu.type;
245 		event->attr.config = config;
246 	}
247 	return -ENOENT;
248 }
249 
250 /*
251  * Grouping of IBS events is not possible since IBS can have only
252  * one event active at any point in time.
253  */
validate_group(struct perf_event * event)254 static int validate_group(struct perf_event *event)
255 {
256 	struct perf_event *sibling;
257 
258 	if (event->group_leader == event)
259 		return 0;
260 
261 	if (event->group_leader->pmu == event->pmu)
262 		return -EINVAL;
263 
264 	for_each_sibling_event(sibling, event->group_leader) {
265 		if (sibling->pmu == event->pmu)
266 			return -EINVAL;
267 	}
268 	return 0;
269 }
270 
perf_ibs_init(struct perf_event * event)271 static int perf_ibs_init(struct perf_event *event)
272 {
273 	struct hw_perf_event *hwc = &event->hw;
274 	struct perf_ibs *perf_ibs;
275 	u64 max_cnt, config;
276 	int ret;
277 
278 	perf_ibs = get_ibs_pmu(event->attr.type);
279 	if (!perf_ibs)
280 		return -ENOENT;
281 
282 	config = event->attr.config;
283 
284 	if (event->pmu != &perf_ibs->pmu)
285 		return -ENOENT;
286 
287 	if (config & ~perf_ibs->config_mask)
288 		return -EINVAL;
289 
290 	ret = validate_group(event);
291 	if (ret)
292 		return ret;
293 
294 	if (hwc->sample_period) {
295 		if (config & perf_ibs->cnt_mask)
296 			/* raw max_cnt may not be set */
297 			return -EINVAL;
298 		if (!event->attr.sample_freq && hwc->sample_period & 0x0f)
299 			/*
300 			 * lower 4 bits can not be set in ibs max cnt,
301 			 * but allowing it in case we adjust the
302 			 * sample period to set a frequency.
303 			 */
304 			return -EINVAL;
305 		hwc->sample_period &= ~0x0FULL;
306 		if (!hwc->sample_period)
307 			hwc->sample_period = 0x10;
308 	} else {
309 		max_cnt = config & perf_ibs->cnt_mask;
310 		config &= ~perf_ibs->cnt_mask;
311 		event->attr.sample_period = max_cnt << 4;
312 		hwc->sample_period = event->attr.sample_period;
313 	}
314 
315 	if (!hwc->sample_period)
316 		return -EINVAL;
317 
318 	/*
319 	 * If we modify hwc->sample_period, we also need to update
320 	 * hwc->last_period and hwc->period_left.
321 	 */
322 	hwc->last_period = hwc->sample_period;
323 	local64_set(&hwc->period_left, hwc->sample_period);
324 
325 	hwc->config_base = perf_ibs->msr;
326 	hwc->config = config;
327 
328 	return 0;
329 }
330 
perf_ibs_set_period(struct perf_ibs * perf_ibs,struct hw_perf_event * hwc,u64 * period)331 static int perf_ibs_set_period(struct perf_ibs *perf_ibs,
332 			       struct hw_perf_event *hwc, u64 *period)
333 {
334 	int overflow;
335 
336 	/* ignore lower 4 bits in min count: */
337 	overflow = perf_event_set_period(hwc, 1<<4, perf_ibs->max_period, period);
338 	local64_set(&hwc->prev_count, 0);
339 
340 	return overflow;
341 }
342 
get_ibs_fetch_count(u64 config)343 static u64 get_ibs_fetch_count(u64 config)
344 {
345 	union ibs_fetch_ctl fetch_ctl = (union ibs_fetch_ctl)config;
346 
347 	return fetch_ctl.fetch_cnt << 4;
348 }
349 
get_ibs_op_count(u64 config)350 static u64 get_ibs_op_count(u64 config)
351 {
352 	union ibs_op_ctl op_ctl = (union ibs_op_ctl)config;
353 	u64 count = 0;
354 
355 	/*
356 	 * If the internal 27-bit counter rolled over, the count is MaxCnt
357 	 * and the lower 7 bits of CurCnt are randomized.
358 	 * Otherwise CurCnt has the full 27-bit current counter value.
359 	 */
360 	if (op_ctl.op_val) {
361 		count = op_ctl.opmaxcnt << 4;
362 		if (ibs_caps & IBS_CAPS_OPCNTEXT)
363 			count += op_ctl.opmaxcnt_ext << 20;
364 	} else if (ibs_caps & IBS_CAPS_RDWROPCNT) {
365 		count = op_ctl.opcurcnt;
366 	}
367 
368 	return count;
369 }
370 
371 static void
perf_ibs_event_update(struct perf_ibs * perf_ibs,struct perf_event * event,u64 * config)372 perf_ibs_event_update(struct perf_ibs *perf_ibs, struct perf_event *event,
373 		      u64 *config)
374 {
375 	u64 count = perf_ibs->get_count(*config);
376 
377 	/*
378 	 * Set width to 64 since we do not overflow on max width but
379 	 * instead on max count. In perf_ibs_set_period() we clear
380 	 * prev count manually on overflow.
381 	 */
382 	while (!perf_event_try_update(event, count, 64)) {
383 		rdmsrl(event->hw.config_base, *config);
384 		count = perf_ibs->get_count(*config);
385 	}
386 }
387 
perf_ibs_enable_event(struct perf_ibs * perf_ibs,struct hw_perf_event * hwc,u64 config)388 static inline void perf_ibs_enable_event(struct perf_ibs *perf_ibs,
389 					 struct hw_perf_event *hwc, u64 config)
390 {
391 	u64 tmp = hwc->config | config;
392 
393 	if (perf_ibs->fetch_count_reset_broken)
394 		wrmsrl(hwc->config_base, tmp & ~perf_ibs->enable_mask);
395 
396 	wrmsrl(hwc->config_base, tmp | perf_ibs->enable_mask);
397 }
398 
399 /*
400  * Erratum #420 Instruction-Based Sampling Engine May Generate
401  * Interrupt that Cannot Be Cleared:
402  *
403  * Must clear counter mask first, then clear the enable bit. See
404  * Revision Guide for AMD Family 10h Processors, Publication #41322.
405  */
perf_ibs_disable_event(struct perf_ibs * perf_ibs,struct hw_perf_event * hwc,u64 config)406 static inline void perf_ibs_disable_event(struct perf_ibs *perf_ibs,
407 					  struct hw_perf_event *hwc, u64 config)
408 {
409 	config &= ~perf_ibs->cnt_mask;
410 	if (boot_cpu_data.x86 == 0x10)
411 		wrmsrl(hwc->config_base, config);
412 	config &= ~perf_ibs->enable_mask;
413 	wrmsrl(hwc->config_base, config);
414 }
415 
416 /*
417  * We cannot restore the ibs pmu state, so we always needs to update
418  * the event while stopping it and then reset the state when starting
419  * again. Thus, ignoring PERF_EF_RELOAD and PERF_EF_UPDATE flags in
420  * perf_ibs_start()/perf_ibs_stop() and instead always do it.
421  */
perf_ibs_start(struct perf_event * event,int flags)422 static void perf_ibs_start(struct perf_event *event, int flags)
423 {
424 	struct hw_perf_event *hwc = &event->hw;
425 	struct perf_ibs *perf_ibs = container_of(event->pmu, struct perf_ibs, pmu);
426 	struct cpu_perf_ibs *pcpu = this_cpu_ptr(perf_ibs->pcpu);
427 	u64 period, config = 0;
428 
429 	if (WARN_ON_ONCE(!(hwc->state & PERF_HES_STOPPED)))
430 		return;
431 
432 	WARN_ON_ONCE(!(hwc->state & PERF_HES_UPTODATE));
433 	hwc->state = 0;
434 
435 	perf_ibs_set_period(perf_ibs, hwc, &period);
436 	if (perf_ibs == &perf_ibs_op && (ibs_caps & IBS_CAPS_OPCNTEXT)) {
437 		config |= period & IBS_OP_MAX_CNT_EXT_MASK;
438 		period &= ~IBS_OP_MAX_CNT_EXT_MASK;
439 	}
440 	config |= period >> 4;
441 
442 	/*
443 	 * Set STARTED before enabling the hardware, such that a subsequent NMI
444 	 * must observe it.
445 	 */
446 	set_bit(IBS_STARTED,    pcpu->state);
447 	clear_bit(IBS_STOPPING, pcpu->state);
448 	perf_ibs_enable_event(perf_ibs, hwc, config);
449 
450 	perf_event_update_userpage(event);
451 }
452 
perf_ibs_stop(struct perf_event * event,int flags)453 static void perf_ibs_stop(struct perf_event *event, int flags)
454 {
455 	struct hw_perf_event *hwc = &event->hw;
456 	struct perf_ibs *perf_ibs = container_of(event->pmu, struct perf_ibs, pmu);
457 	struct cpu_perf_ibs *pcpu = this_cpu_ptr(perf_ibs->pcpu);
458 	u64 config;
459 	int stopping;
460 
461 	if (test_and_set_bit(IBS_STOPPING, pcpu->state))
462 		return;
463 
464 	stopping = test_bit(IBS_STARTED, pcpu->state);
465 
466 	if (!stopping && (hwc->state & PERF_HES_UPTODATE))
467 		return;
468 
469 	rdmsrl(hwc->config_base, config);
470 
471 	if (stopping) {
472 		/*
473 		 * Set STOPPED before disabling the hardware, such that it
474 		 * must be visible to NMIs the moment we clear the EN bit,
475 		 * at which point we can generate an !VALID sample which
476 		 * we need to consume.
477 		 */
478 		set_bit(IBS_STOPPED, pcpu->state);
479 		perf_ibs_disable_event(perf_ibs, hwc, config);
480 		/*
481 		 * Clear STARTED after disabling the hardware; if it were
482 		 * cleared before an NMI hitting after the clear but before
483 		 * clearing the EN bit might think it a spurious NMI and not
484 		 * handle it.
485 		 *
486 		 * Clearing it after, however, creates the problem of the NMI
487 		 * handler seeing STARTED but not having a valid sample.
488 		 */
489 		clear_bit(IBS_STARTED, pcpu->state);
490 		WARN_ON_ONCE(hwc->state & PERF_HES_STOPPED);
491 		hwc->state |= PERF_HES_STOPPED;
492 	}
493 
494 	if (hwc->state & PERF_HES_UPTODATE)
495 		return;
496 
497 	/*
498 	 * Clear valid bit to not count rollovers on update, rollovers
499 	 * are only updated in the irq handler.
500 	 */
501 	config &= ~perf_ibs->valid_mask;
502 
503 	perf_ibs_event_update(perf_ibs, event, &config);
504 	hwc->state |= PERF_HES_UPTODATE;
505 }
506 
perf_ibs_add(struct perf_event * event,int flags)507 static int perf_ibs_add(struct perf_event *event, int flags)
508 {
509 	struct perf_ibs *perf_ibs = container_of(event->pmu, struct perf_ibs, pmu);
510 	struct cpu_perf_ibs *pcpu = this_cpu_ptr(perf_ibs->pcpu);
511 
512 	if (test_and_set_bit(IBS_ENABLED, pcpu->state))
513 		return -ENOSPC;
514 
515 	event->hw.state = PERF_HES_UPTODATE | PERF_HES_STOPPED;
516 
517 	pcpu->event = event;
518 
519 	if (flags & PERF_EF_START)
520 		perf_ibs_start(event, PERF_EF_RELOAD);
521 
522 	return 0;
523 }
524 
perf_ibs_del(struct perf_event * event,int flags)525 static void perf_ibs_del(struct perf_event *event, int flags)
526 {
527 	struct perf_ibs *perf_ibs = container_of(event->pmu, struct perf_ibs, pmu);
528 	struct cpu_perf_ibs *pcpu = this_cpu_ptr(perf_ibs->pcpu);
529 
530 	if (!test_and_clear_bit(IBS_ENABLED, pcpu->state))
531 		return;
532 
533 	perf_ibs_stop(event, PERF_EF_UPDATE);
534 
535 	pcpu->event = NULL;
536 
537 	perf_event_update_userpage(event);
538 }
539 
perf_ibs_read(struct perf_event * event)540 static void perf_ibs_read(struct perf_event *event) { }
541 
542 /*
543  * We need to initialize with empty group if all attributes in the
544  * group are dynamic.
545  */
546 static struct attribute *attrs_empty[] = {
547 	NULL,
548 };
549 
550 static struct attribute_group empty_format_group = {
551 	.name = "format",
552 	.attrs = attrs_empty,
553 };
554 
555 static struct attribute_group empty_caps_group = {
556 	.name = "caps",
557 	.attrs = attrs_empty,
558 };
559 
560 static const struct attribute_group *empty_attr_groups[] = {
561 	&empty_format_group,
562 	&empty_caps_group,
563 	NULL,
564 };
565 
566 PMU_FORMAT_ATTR(rand_en,	"config:57");
567 PMU_FORMAT_ATTR(cnt_ctl,	"config:19");
568 PMU_EVENT_ATTR_STRING(l3missonly, fetch_l3missonly, "config:59");
569 PMU_EVENT_ATTR_STRING(l3missonly, op_l3missonly, "config:16");
570 PMU_EVENT_ATTR_STRING(zen4_ibs_extensions, zen4_ibs_extensions, "1");
571 
572 static umode_t
zen4_ibs_extensions_is_visible(struct kobject * kobj,struct attribute * attr,int i)573 zen4_ibs_extensions_is_visible(struct kobject *kobj, struct attribute *attr, int i)
574 {
575 	return ibs_caps & IBS_CAPS_ZEN4 ? attr->mode : 0;
576 }
577 
578 static struct attribute *rand_en_attrs[] = {
579 	&format_attr_rand_en.attr,
580 	NULL,
581 };
582 
583 static struct attribute *fetch_l3missonly_attrs[] = {
584 	&fetch_l3missonly.attr.attr,
585 	NULL,
586 };
587 
588 static struct attribute *zen4_ibs_extensions_attrs[] = {
589 	&zen4_ibs_extensions.attr.attr,
590 	NULL,
591 };
592 
593 static struct attribute_group group_rand_en = {
594 	.name = "format",
595 	.attrs = rand_en_attrs,
596 };
597 
598 static struct attribute_group group_fetch_l3missonly = {
599 	.name = "format",
600 	.attrs = fetch_l3missonly_attrs,
601 	.is_visible = zen4_ibs_extensions_is_visible,
602 };
603 
604 static struct attribute_group group_zen4_ibs_extensions = {
605 	.name = "caps",
606 	.attrs = zen4_ibs_extensions_attrs,
607 	.is_visible = zen4_ibs_extensions_is_visible,
608 };
609 
610 static const struct attribute_group *fetch_attr_groups[] = {
611 	&group_rand_en,
612 	&empty_caps_group,
613 	NULL,
614 };
615 
616 static const struct attribute_group *fetch_attr_update[] = {
617 	&group_fetch_l3missonly,
618 	&group_zen4_ibs_extensions,
619 	NULL,
620 };
621 
622 static umode_t
cnt_ctl_is_visible(struct kobject * kobj,struct attribute * attr,int i)623 cnt_ctl_is_visible(struct kobject *kobj, struct attribute *attr, int i)
624 {
625 	return ibs_caps & IBS_CAPS_OPCNT ? attr->mode : 0;
626 }
627 
628 static struct attribute *cnt_ctl_attrs[] = {
629 	&format_attr_cnt_ctl.attr,
630 	NULL,
631 };
632 
633 static struct attribute *op_l3missonly_attrs[] = {
634 	&op_l3missonly.attr.attr,
635 	NULL,
636 };
637 
638 static struct attribute_group group_cnt_ctl = {
639 	.name = "format",
640 	.attrs = cnt_ctl_attrs,
641 	.is_visible = cnt_ctl_is_visible,
642 };
643 
644 static struct attribute_group group_op_l3missonly = {
645 	.name = "format",
646 	.attrs = op_l3missonly_attrs,
647 	.is_visible = zen4_ibs_extensions_is_visible,
648 };
649 
650 static const struct attribute_group *op_attr_update[] = {
651 	&group_cnt_ctl,
652 	&group_op_l3missonly,
653 	&group_zen4_ibs_extensions,
654 	NULL,
655 };
656 
657 static struct perf_ibs perf_ibs_fetch = {
658 	.pmu = {
659 		.task_ctx_nr	= perf_hw_context,
660 
661 		.event_init	= perf_ibs_init,
662 		.add		= perf_ibs_add,
663 		.del		= perf_ibs_del,
664 		.start		= perf_ibs_start,
665 		.stop		= perf_ibs_stop,
666 		.read		= perf_ibs_read,
667 		.capabilities	= PERF_PMU_CAP_NO_EXCLUDE,
668 	},
669 	.msr			= MSR_AMD64_IBSFETCHCTL,
670 	.config_mask		= IBS_FETCH_CONFIG_MASK,
671 	.cnt_mask		= IBS_FETCH_MAX_CNT,
672 	.enable_mask		= IBS_FETCH_ENABLE,
673 	.valid_mask		= IBS_FETCH_VAL,
674 	.max_period		= IBS_FETCH_MAX_CNT << 4,
675 	.offset_mask		= { MSR_AMD64_IBSFETCH_REG_MASK },
676 	.offset_max		= MSR_AMD64_IBSFETCH_REG_COUNT,
677 
678 	.get_count		= get_ibs_fetch_count,
679 };
680 
681 static struct perf_ibs perf_ibs_op = {
682 	.pmu = {
683 		.task_ctx_nr	= perf_hw_context,
684 
685 		.event_init	= perf_ibs_init,
686 		.add		= perf_ibs_add,
687 		.del		= perf_ibs_del,
688 		.start		= perf_ibs_start,
689 		.stop		= perf_ibs_stop,
690 		.read		= perf_ibs_read,
691 		.capabilities	= PERF_PMU_CAP_NO_EXCLUDE,
692 	},
693 	.msr			= MSR_AMD64_IBSOPCTL,
694 	.config_mask		= IBS_OP_CONFIG_MASK,
695 	.cnt_mask		= IBS_OP_MAX_CNT | IBS_OP_CUR_CNT |
696 				  IBS_OP_CUR_CNT_RAND,
697 	.enable_mask		= IBS_OP_ENABLE,
698 	.valid_mask		= IBS_OP_VAL,
699 	.max_period		= IBS_OP_MAX_CNT << 4,
700 	.offset_mask		= { MSR_AMD64_IBSOP_REG_MASK },
701 	.offset_max		= MSR_AMD64_IBSOP_REG_COUNT,
702 
703 	.get_count		= get_ibs_op_count,
704 };
705 
perf_ibs_get_mem_op(union ibs_op_data3 * op_data3,struct perf_sample_data * data)706 static void perf_ibs_get_mem_op(union ibs_op_data3 *op_data3,
707 				struct perf_sample_data *data)
708 {
709 	union perf_mem_data_src *data_src = &data->data_src;
710 
711 	data_src->mem_op = PERF_MEM_OP_NA;
712 
713 	if (op_data3->ld_op)
714 		data_src->mem_op = PERF_MEM_OP_LOAD;
715 	else if (op_data3->st_op)
716 		data_src->mem_op = PERF_MEM_OP_STORE;
717 }
718 
719 /*
720  * Processors having CPUID_Fn8000001B_EAX[11] aka IBS_CAPS_ZEN4 has
721  * more fine granular DataSrc encodings. Others have coarse.
722  */
perf_ibs_data_src(union ibs_op_data2 * op_data2)723 static u8 perf_ibs_data_src(union ibs_op_data2 *op_data2)
724 {
725 	if (ibs_caps & IBS_CAPS_ZEN4)
726 		return (op_data2->data_src_hi << 3) | op_data2->data_src_lo;
727 
728 	return op_data2->data_src_lo;
729 }
730 
731 #define	L(x)		(PERF_MEM_S(LVL, x) | PERF_MEM_S(LVL, HIT))
732 #define	LN(x)		PERF_MEM_S(LVLNUM, x)
733 #define	REM		PERF_MEM_S(REMOTE, REMOTE)
734 #define	HOPS(x)		PERF_MEM_S(HOPS, x)
735 
736 static u64 g_data_src[8] = {
737 	[IBS_DATA_SRC_LOC_CACHE]	  = L(L3) | L(REM_CCE1) | LN(ANY_CACHE) | HOPS(0),
738 	[IBS_DATA_SRC_DRAM]		  = L(LOC_RAM) | LN(RAM),
739 	[IBS_DATA_SRC_REM_CACHE]	  = L(REM_CCE2) | LN(ANY_CACHE) | REM | HOPS(1),
740 	[IBS_DATA_SRC_IO]		  = L(IO) | LN(IO),
741 };
742 
743 #define RMT_NODE_BITS			(1 << IBS_DATA_SRC_DRAM)
744 #define RMT_NODE_APPLICABLE(x)		(RMT_NODE_BITS & (1 << x))
745 
746 static u64 g_zen4_data_src[32] = {
747 	[IBS_DATA_SRC_EXT_LOC_CACHE]	  = L(L3) | LN(L3),
748 	[IBS_DATA_SRC_EXT_NEAR_CCX_CACHE] = L(REM_CCE1) | LN(ANY_CACHE) | REM | HOPS(0),
749 	[IBS_DATA_SRC_EXT_DRAM]		  = L(LOC_RAM) | LN(RAM),
750 	[IBS_DATA_SRC_EXT_FAR_CCX_CACHE]  = L(REM_CCE2) | LN(ANY_CACHE) | REM | HOPS(1),
751 	[IBS_DATA_SRC_EXT_PMEM]		  = LN(PMEM),
752 	[IBS_DATA_SRC_EXT_IO]		  = L(IO) | LN(IO),
753 	[IBS_DATA_SRC_EXT_EXT_MEM]	  = LN(CXL),
754 };
755 
756 #define ZEN4_RMT_NODE_BITS		((1 << IBS_DATA_SRC_EXT_DRAM) | \
757 					 (1 << IBS_DATA_SRC_EXT_PMEM) | \
758 					 (1 << IBS_DATA_SRC_EXT_EXT_MEM))
759 #define ZEN4_RMT_NODE_APPLICABLE(x)	(ZEN4_RMT_NODE_BITS & (1 << x))
760 
perf_ibs_get_mem_lvl(union ibs_op_data2 * op_data2,union ibs_op_data3 * op_data3,struct perf_sample_data * data)761 static __u64 perf_ibs_get_mem_lvl(union ibs_op_data2 *op_data2,
762 				  union ibs_op_data3 *op_data3,
763 				  struct perf_sample_data *data)
764 {
765 	union perf_mem_data_src *data_src = &data->data_src;
766 	u8 ibs_data_src = perf_ibs_data_src(op_data2);
767 
768 	data_src->mem_lvl = 0;
769 	data_src->mem_lvl_num = 0;
770 
771 	/*
772 	 * DcMiss, L2Miss, DataSrc, DcMissLat etc. are all invalid for Uncached
773 	 * memory accesses. So, check DcUcMemAcc bit early.
774 	 */
775 	if (op_data3->dc_uc_mem_acc && ibs_data_src != IBS_DATA_SRC_EXT_IO)
776 		return L(UNC) | LN(UNC);
777 
778 	/* L1 Hit */
779 	if (op_data3->dc_miss == 0)
780 		return L(L1) | LN(L1);
781 
782 	/* L2 Hit */
783 	if (op_data3->l2_miss == 0) {
784 		/* Erratum #1293 */
785 		if (boot_cpu_data.x86 != 0x19 || boot_cpu_data.x86_model > 0xF ||
786 		    !(op_data3->sw_pf || op_data3->dc_miss_no_mab_alloc))
787 			return L(L2) | LN(L2);
788 	}
789 
790 	/*
791 	 * OP_DATA2 is valid only for load ops. Skip all checks which
792 	 * uses OP_DATA2[DataSrc].
793 	 */
794 	if (data_src->mem_op != PERF_MEM_OP_LOAD)
795 		goto check_mab;
796 
797 	if (ibs_caps & IBS_CAPS_ZEN4) {
798 		u64 val = g_zen4_data_src[ibs_data_src];
799 
800 		if (!val)
801 			goto check_mab;
802 
803 		/* HOPS_1 because IBS doesn't provide remote socket detail */
804 		if (op_data2->rmt_node && ZEN4_RMT_NODE_APPLICABLE(ibs_data_src)) {
805 			if (ibs_data_src == IBS_DATA_SRC_EXT_DRAM)
806 				val = L(REM_RAM1) | LN(RAM) | REM | HOPS(1);
807 			else
808 				val |= REM | HOPS(1);
809 		}
810 
811 		return val;
812 	} else {
813 		u64 val = g_data_src[ibs_data_src];
814 
815 		if (!val)
816 			goto check_mab;
817 
818 		/* HOPS_1 because IBS doesn't provide remote socket detail */
819 		if (op_data2->rmt_node && RMT_NODE_APPLICABLE(ibs_data_src)) {
820 			if (ibs_data_src == IBS_DATA_SRC_DRAM)
821 				val = L(REM_RAM1) | LN(RAM) | REM | HOPS(1);
822 			else
823 				val |= REM | HOPS(1);
824 		}
825 
826 		return val;
827 	}
828 
829 check_mab:
830 	/*
831 	 * MAB (Miss Address Buffer) Hit. MAB keeps track of outstanding
832 	 * DC misses. However, such data may come from any level in mem
833 	 * hierarchy. IBS provides detail about both MAB as well as actual
834 	 * DataSrc simultaneously. Prioritize DataSrc over MAB, i.e. set
835 	 * MAB only when IBS fails to provide DataSrc.
836 	 */
837 	if (op_data3->dc_miss_no_mab_alloc)
838 		return L(LFB) | LN(LFB);
839 
840 	/* Don't set HIT with NA */
841 	return PERF_MEM_S(LVL, NA) | LN(NA);
842 }
843 
perf_ibs_cache_hit_st_valid(void)844 static bool perf_ibs_cache_hit_st_valid(void)
845 {
846 	/* 0: Uninitialized, 1: Valid, -1: Invalid */
847 	static int cache_hit_st_valid;
848 
849 	if (unlikely(!cache_hit_st_valid)) {
850 		if (boot_cpu_data.x86 == 0x19 &&
851 		    (boot_cpu_data.x86_model <= 0xF ||
852 		    (boot_cpu_data.x86_model >= 0x20 &&
853 		     boot_cpu_data.x86_model <= 0x5F))) {
854 			cache_hit_st_valid = -1;
855 		} else {
856 			cache_hit_st_valid = 1;
857 		}
858 	}
859 
860 	return cache_hit_st_valid == 1;
861 }
862 
perf_ibs_get_mem_snoop(union ibs_op_data2 * op_data2,struct perf_sample_data * data)863 static void perf_ibs_get_mem_snoop(union ibs_op_data2 *op_data2,
864 				   struct perf_sample_data *data)
865 {
866 	union perf_mem_data_src *data_src = &data->data_src;
867 	u8 ibs_data_src;
868 
869 	data_src->mem_snoop = PERF_MEM_SNOOP_NA;
870 
871 	if (!perf_ibs_cache_hit_st_valid() ||
872 	    data_src->mem_op != PERF_MEM_OP_LOAD ||
873 	    data_src->mem_lvl & PERF_MEM_LVL_L1 ||
874 	    data_src->mem_lvl & PERF_MEM_LVL_L2 ||
875 	    op_data2->cache_hit_st)
876 		return;
877 
878 	ibs_data_src = perf_ibs_data_src(op_data2);
879 
880 	if (ibs_caps & IBS_CAPS_ZEN4) {
881 		if (ibs_data_src == IBS_DATA_SRC_EXT_LOC_CACHE ||
882 		    ibs_data_src == IBS_DATA_SRC_EXT_NEAR_CCX_CACHE ||
883 		    ibs_data_src == IBS_DATA_SRC_EXT_FAR_CCX_CACHE)
884 			data_src->mem_snoop = PERF_MEM_SNOOP_HITM;
885 	} else if (ibs_data_src == IBS_DATA_SRC_LOC_CACHE) {
886 		data_src->mem_snoop = PERF_MEM_SNOOP_HITM;
887 	}
888 }
889 
perf_ibs_get_tlb_lvl(union ibs_op_data3 * op_data3,struct perf_sample_data * data)890 static void perf_ibs_get_tlb_lvl(union ibs_op_data3 *op_data3,
891 				 struct perf_sample_data *data)
892 {
893 	union perf_mem_data_src *data_src = &data->data_src;
894 
895 	data_src->mem_dtlb = PERF_MEM_TLB_NA;
896 
897 	if (!op_data3->dc_lin_addr_valid)
898 		return;
899 
900 	if (!op_data3->dc_l1tlb_miss) {
901 		data_src->mem_dtlb = PERF_MEM_TLB_L1 | PERF_MEM_TLB_HIT;
902 		return;
903 	}
904 
905 	if (!op_data3->dc_l2tlb_miss) {
906 		data_src->mem_dtlb = PERF_MEM_TLB_L2 | PERF_MEM_TLB_HIT;
907 		return;
908 	}
909 
910 	data_src->mem_dtlb = PERF_MEM_TLB_L2 | PERF_MEM_TLB_MISS;
911 }
912 
perf_ibs_get_mem_lock(union ibs_op_data3 * op_data3,struct perf_sample_data * data)913 static void perf_ibs_get_mem_lock(union ibs_op_data3 *op_data3,
914 				  struct perf_sample_data *data)
915 {
916 	union perf_mem_data_src *data_src = &data->data_src;
917 
918 	data_src->mem_lock = PERF_MEM_LOCK_NA;
919 
920 	if (op_data3->dc_locked_op)
921 		data_src->mem_lock = PERF_MEM_LOCK_LOCKED;
922 }
923 
924 #define ibs_op_msr_idx(msr)	(msr - MSR_AMD64_IBSOPCTL)
925 
perf_ibs_get_data_src(struct perf_ibs_data * ibs_data,struct perf_sample_data * data,union ibs_op_data2 * op_data2,union ibs_op_data3 * op_data3)926 static void perf_ibs_get_data_src(struct perf_ibs_data *ibs_data,
927 				  struct perf_sample_data *data,
928 				  union ibs_op_data2 *op_data2,
929 				  union ibs_op_data3 *op_data3)
930 {
931 	union perf_mem_data_src *data_src = &data->data_src;
932 
933 	data_src->val |= perf_ibs_get_mem_lvl(op_data2, op_data3, data);
934 	perf_ibs_get_mem_snoop(op_data2, data);
935 	perf_ibs_get_tlb_lvl(op_data3, data);
936 	perf_ibs_get_mem_lock(op_data3, data);
937 }
938 
perf_ibs_get_op_data2(struct perf_ibs_data * ibs_data,union ibs_op_data3 * op_data3)939 static __u64 perf_ibs_get_op_data2(struct perf_ibs_data *ibs_data,
940 				   union ibs_op_data3 *op_data3)
941 {
942 	__u64 val = ibs_data->regs[ibs_op_msr_idx(MSR_AMD64_IBSOPDATA2)];
943 
944 	/* Erratum #1293 */
945 	if (boot_cpu_data.x86 == 0x19 && boot_cpu_data.x86_model <= 0xF &&
946 	    (op_data3->sw_pf || op_data3->dc_miss_no_mab_alloc)) {
947 		/*
948 		 * OP_DATA2 has only two fields on Zen3: DataSrc and RmtNode.
949 		 * DataSrc=0 is 'No valid status' and RmtNode is invalid when
950 		 * DataSrc=0.
951 		 */
952 		val = 0;
953 	}
954 	return val;
955 }
956 
perf_ibs_parse_ld_st_data(__u64 sample_type,struct perf_ibs_data * ibs_data,struct perf_sample_data * data)957 static void perf_ibs_parse_ld_st_data(__u64 sample_type,
958 				      struct perf_ibs_data *ibs_data,
959 				      struct perf_sample_data *data)
960 {
961 	union ibs_op_data3 op_data3;
962 	union ibs_op_data2 op_data2;
963 	union ibs_op_data op_data;
964 
965 	data->data_src.val = PERF_MEM_NA;
966 	op_data3.val = ibs_data->regs[ibs_op_msr_idx(MSR_AMD64_IBSOPDATA3)];
967 
968 	perf_ibs_get_mem_op(&op_data3, data);
969 	if (data->data_src.mem_op != PERF_MEM_OP_LOAD &&
970 	    data->data_src.mem_op != PERF_MEM_OP_STORE)
971 		return;
972 
973 	op_data2.val = perf_ibs_get_op_data2(ibs_data, &op_data3);
974 
975 	if (sample_type & PERF_SAMPLE_DATA_SRC) {
976 		perf_ibs_get_data_src(ibs_data, data, &op_data2, &op_data3);
977 		data->sample_flags |= PERF_SAMPLE_DATA_SRC;
978 	}
979 
980 	if (sample_type & PERF_SAMPLE_WEIGHT_TYPE && op_data3.dc_miss &&
981 	    data->data_src.mem_op == PERF_MEM_OP_LOAD) {
982 		op_data.val = ibs_data->regs[ibs_op_msr_idx(MSR_AMD64_IBSOPDATA)];
983 
984 		if (sample_type & PERF_SAMPLE_WEIGHT_STRUCT) {
985 			data->weight.var1_dw = op_data3.dc_miss_lat;
986 			data->weight.var2_w = op_data.tag_to_ret_ctr;
987 		} else if (sample_type & PERF_SAMPLE_WEIGHT) {
988 			data->weight.full = op_data3.dc_miss_lat;
989 		}
990 		data->sample_flags |= PERF_SAMPLE_WEIGHT_TYPE;
991 	}
992 
993 	if (sample_type & PERF_SAMPLE_ADDR && op_data3.dc_lin_addr_valid) {
994 		data->addr = ibs_data->regs[ibs_op_msr_idx(MSR_AMD64_IBSDCLINAD)];
995 		data->sample_flags |= PERF_SAMPLE_ADDR;
996 	}
997 
998 	if (sample_type & PERF_SAMPLE_PHYS_ADDR && op_data3.dc_phy_addr_valid) {
999 		data->phys_addr = ibs_data->regs[ibs_op_msr_idx(MSR_AMD64_IBSDCPHYSAD)];
1000 		data->sample_flags |= PERF_SAMPLE_PHYS_ADDR;
1001 	}
1002 }
1003 
perf_ibs_get_offset_max(struct perf_ibs * perf_ibs,u64 sample_type,int check_rip)1004 static int perf_ibs_get_offset_max(struct perf_ibs *perf_ibs, u64 sample_type,
1005 				   int check_rip)
1006 {
1007 	if (sample_type & PERF_SAMPLE_RAW ||
1008 	    (perf_ibs == &perf_ibs_op &&
1009 	     (sample_type & PERF_SAMPLE_DATA_SRC ||
1010 	      sample_type & PERF_SAMPLE_WEIGHT_TYPE ||
1011 	      sample_type & PERF_SAMPLE_ADDR ||
1012 	      sample_type & PERF_SAMPLE_PHYS_ADDR)))
1013 		return perf_ibs->offset_max;
1014 	else if (check_rip)
1015 		return 3;
1016 	return 1;
1017 }
1018 
perf_ibs_handle_irq(struct perf_ibs * perf_ibs,struct pt_regs * iregs)1019 static int perf_ibs_handle_irq(struct perf_ibs *perf_ibs, struct pt_regs *iregs)
1020 {
1021 	struct cpu_perf_ibs *pcpu = this_cpu_ptr(perf_ibs->pcpu);
1022 	struct perf_event *event = pcpu->event;
1023 	struct hw_perf_event *hwc;
1024 	struct perf_sample_data data;
1025 	struct perf_raw_record raw;
1026 	struct pt_regs regs;
1027 	struct perf_ibs_data ibs_data;
1028 	int offset, size, check_rip, offset_max, throttle = 0;
1029 	unsigned int msr;
1030 	u64 *buf, *config, period, new_config = 0;
1031 
1032 	if (!test_bit(IBS_STARTED, pcpu->state)) {
1033 fail:
1034 		/*
1035 		 * Catch spurious interrupts after stopping IBS: After
1036 		 * disabling IBS there could be still incoming NMIs
1037 		 * with samples that even have the valid bit cleared.
1038 		 * Mark all this NMIs as handled.
1039 		 */
1040 		if (test_and_clear_bit(IBS_STOPPED, pcpu->state))
1041 			return 1;
1042 
1043 		return 0;
1044 	}
1045 
1046 	if (WARN_ON_ONCE(!event))
1047 		goto fail;
1048 
1049 	hwc = &event->hw;
1050 	msr = hwc->config_base;
1051 	buf = ibs_data.regs;
1052 	rdmsrl(msr, *buf);
1053 	if (!(*buf++ & perf_ibs->valid_mask))
1054 		goto fail;
1055 
1056 	config = &ibs_data.regs[0];
1057 	perf_ibs_event_update(perf_ibs, event, config);
1058 	perf_sample_data_init(&data, 0, hwc->last_period);
1059 	if (!perf_ibs_set_period(perf_ibs, hwc, &period))
1060 		goto out;	/* no sw counter overflow */
1061 
1062 	ibs_data.caps = ibs_caps;
1063 	size = 1;
1064 	offset = 1;
1065 	check_rip = (perf_ibs == &perf_ibs_op && (ibs_caps & IBS_CAPS_RIPINVALIDCHK));
1066 
1067 	offset_max = perf_ibs_get_offset_max(perf_ibs, event->attr.sample_type, check_rip);
1068 
1069 	do {
1070 		rdmsrl(msr + offset, *buf++);
1071 		size++;
1072 		offset = find_next_bit(perf_ibs->offset_mask,
1073 				       perf_ibs->offset_max,
1074 				       offset + 1);
1075 	} while (offset < offset_max);
1076 	/*
1077 	 * Read IbsBrTarget, IbsOpData4, and IbsExtdCtl separately
1078 	 * depending on their availability.
1079 	 * Can't add to offset_max as they are staggered
1080 	 */
1081 	if (event->attr.sample_type & PERF_SAMPLE_RAW) {
1082 		if (perf_ibs == &perf_ibs_op) {
1083 			if (ibs_caps & IBS_CAPS_BRNTRGT) {
1084 				rdmsrl(MSR_AMD64_IBSBRTARGET, *buf++);
1085 				size++;
1086 			}
1087 			if (ibs_caps & IBS_CAPS_OPDATA4) {
1088 				rdmsrl(MSR_AMD64_IBSOPDATA4, *buf++);
1089 				size++;
1090 			}
1091 		}
1092 		if (perf_ibs == &perf_ibs_fetch && (ibs_caps & IBS_CAPS_FETCHCTLEXTD)) {
1093 			rdmsrl(MSR_AMD64_ICIBSEXTDCTL, *buf++);
1094 			size++;
1095 		}
1096 	}
1097 	ibs_data.size = sizeof(u64) * size;
1098 
1099 	regs = *iregs;
1100 	if (check_rip && (ibs_data.regs[2] & IBS_RIP_INVALID)) {
1101 		regs.flags &= ~PERF_EFLAGS_EXACT;
1102 	} else {
1103 		/* Workaround for erratum #1197 */
1104 		if (perf_ibs->fetch_ignore_if_zero_rip && !(ibs_data.regs[1]))
1105 			goto out;
1106 
1107 		set_linear_ip(&regs, ibs_data.regs[1]);
1108 		regs.flags |= PERF_EFLAGS_EXACT;
1109 	}
1110 
1111 	if (event->attr.sample_type & PERF_SAMPLE_RAW) {
1112 		raw = (struct perf_raw_record){
1113 			.frag = {
1114 				.size = sizeof(u32) + ibs_data.size,
1115 				.data = ibs_data.data,
1116 			},
1117 		};
1118 		perf_sample_save_raw_data(&data, &raw);
1119 	}
1120 
1121 	if (perf_ibs == &perf_ibs_op)
1122 		perf_ibs_parse_ld_st_data(event->attr.sample_type, &ibs_data, &data);
1123 
1124 	/*
1125 	 * rip recorded by IbsOpRip will not be consistent with rsp and rbp
1126 	 * recorded as part of interrupt regs. Thus we need to use rip from
1127 	 * interrupt regs while unwinding call stack.
1128 	 */
1129 	if (event->attr.sample_type & PERF_SAMPLE_CALLCHAIN)
1130 		perf_sample_save_callchain(&data, event, iregs);
1131 
1132 	throttle = perf_event_overflow(event, &data, &regs);
1133 out:
1134 	if (throttle) {
1135 		perf_ibs_stop(event, 0);
1136 	} else {
1137 		if (perf_ibs == &perf_ibs_op) {
1138 			if (ibs_caps & IBS_CAPS_OPCNTEXT) {
1139 				new_config = period & IBS_OP_MAX_CNT_EXT_MASK;
1140 				period &= ~IBS_OP_MAX_CNT_EXT_MASK;
1141 			}
1142 			if ((ibs_caps & IBS_CAPS_RDWROPCNT) && (*config & IBS_OP_CNT_CTL))
1143 				new_config |= *config & IBS_OP_CUR_CNT_RAND;
1144 		}
1145 		new_config |= period >> 4;
1146 
1147 		perf_ibs_enable_event(perf_ibs, hwc, new_config);
1148 	}
1149 
1150 	perf_event_update_userpage(event);
1151 
1152 	return 1;
1153 }
1154 
1155 static int
perf_ibs_nmi_handler(unsigned int cmd,struct pt_regs * regs)1156 perf_ibs_nmi_handler(unsigned int cmd, struct pt_regs *regs)
1157 {
1158 	u64 stamp = sched_clock();
1159 	int handled = 0;
1160 
1161 	handled += perf_ibs_handle_irq(&perf_ibs_fetch, regs);
1162 	handled += perf_ibs_handle_irq(&perf_ibs_op, regs);
1163 
1164 	if (handled)
1165 		inc_irq_stat(apic_perf_irqs);
1166 
1167 	perf_sample_event_took(sched_clock() - stamp);
1168 
1169 	return handled;
1170 }
1171 NOKPROBE_SYMBOL(perf_ibs_nmi_handler);
1172 
perf_ibs_pmu_init(struct perf_ibs * perf_ibs,char * name)1173 static __init int perf_ibs_pmu_init(struct perf_ibs *perf_ibs, char *name)
1174 {
1175 	struct cpu_perf_ibs __percpu *pcpu;
1176 	int ret;
1177 
1178 	pcpu = alloc_percpu(struct cpu_perf_ibs);
1179 	if (!pcpu)
1180 		return -ENOMEM;
1181 
1182 	perf_ibs->pcpu = pcpu;
1183 
1184 	ret = perf_pmu_register(&perf_ibs->pmu, name, -1);
1185 	if (ret) {
1186 		perf_ibs->pcpu = NULL;
1187 		free_percpu(pcpu);
1188 	}
1189 
1190 	return ret;
1191 }
1192 
perf_ibs_fetch_init(void)1193 static __init int perf_ibs_fetch_init(void)
1194 {
1195 	/*
1196 	 * Some chips fail to reset the fetch count when it is written; instead
1197 	 * they need a 0-1 transition of IbsFetchEn.
1198 	 */
1199 	if (boot_cpu_data.x86 >= 0x16 && boot_cpu_data.x86 <= 0x18)
1200 		perf_ibs_fetch.fetch_count_reset_broken = 1;
1201 
1202 	if (boot_cpu_data.x86 == 0x19 && boot_cpu_data.x86_model < 0x10)
1203 		perf_ibs_fetch.fetch_ignore_if_zero_rip = 1;
1204 
1205 	if (ibs_caps & IBS_CAPS_ZEN4)
1206 		perf_ibs_fetch.config_mask |= IBS_FETCH_L3MISSONLY;
1207 
1208 	perf_ibs_fetch.pmu.attr_groups = fetch_attr_groups;
1209 	perf_ibs_fetch.pmu.attr_update = fetch_attr_update;
1210 
1211 	return perf_ibs_pmu_init(&perf_ibs_fetch, "ibs_fetch");
1212 }
1213 
perf_ibs_op_init(void)1214 static __init int perf_ibs_op_init(void)
1215 {
1216 	if (ibs_caps & IBS_CAPS_OPCNT)
1217 		perf_ibs_op.config_mask |= IBS_OP_CNT_CTL;
1218 
1219 	if (ibs_caps & IBS_CAPS_OPCNTEXT) {
1220 		perf_ibs_op.max_period  |= IBS_OP_MAX_CNT_EXT_MASK;
1221 		perf_ibs_op.config_mask	|= IBS_OP_MAX_CNT_EXT_MASK;
1222 		perf_ibs_op.cnt_mask    |= IBS_OP_MAX_CNT_EXT_MASK;
1223 	}
1224 
1225 	if (ibs_caps & IBS_CAPS_ZEN4)
1226 		perf_ibs_op.config_mask |= IBS_OP_L3MISSONLY;
1227 
1228 	perf_ibs_op.pmu.attr_groups = empty_attr_groups;
1229 	perf_ibs_op.pmu.attr_update = op_attr_update;
1230 
1231 	return perf_ibs_pmu_init(&perf_ibs_op, "ibs_op");
1232 }
1233 
perf_event_ibs_init(void)1234 static __init int perf_event_ibs_init(void)
1235 {
1236 	int ret;
1237 
1238 	ret = perf_ibs_fetch_init();
1239 	if (ret)
1240 		return ret;
1241 
1242 	ret = perf_ibs_op_init();
1243 	if (ret)
1244 		goto err_op;
1245 
1246 	ret = register_nmi_handler(NMI_LOCAL, perf_ibs_nmi_handler, 0, "perf_ibs");
1247 	if (ret)
1248 		goto err_nmi;
1249 
1250 	pr_info("perf: AMD IBS detected (0x%08x)\n", ibs_caps);
1251 	return 0;
1252 
1253 err_nmi:
1254 	perf_pmu_unregister(&perf_ibs_op.pmu);
1255 	free_percpu(perf_ibs_op.pcpu);
1256 	perf_ibs_op.pcpu = NULL;
1257 err_op:
1258 	perf_pmu_unregister(&perf_ibs_fetch.pmu);
1259 	free_percpu(perf_ibs_fetch.pcpu);
1260 	perf_ibs_fetch.pcpu = NULL;
1261 
1262 	return ret;
1263 }
1264 
1265 #else /* defined(CONFIG_PERF_EVENTS) && defined(CONFIG_CPU_SUP_AMD) */
1266 
perf_event_ibs_init(void)1267 static __init int perf_event_ibs_init(void)
1268 {
1269 	return 0;
1270 }
1271 
1272 #endif
1273 
1274 /* IBS - apic initialization, for perf and oprofile */
1275 
__get_ibs_caps(void)1276 static __init u32 __get_ibs_caps(void)
1277 {
1278 	u32 caps;
1279 	unsigned int max_level;
1280 
1281 	if (!boot_cpu_has(X86_FEATURE_IBS))
1282 		return 0;
1283 
1284 	/* check IBS cpuid feature flags */
1285 	max_level = cpuid_eax(0x80000000);
1286 	if (max_level < IBS_CPUID_FEATURES)
1287 		return IBS_CAPS_DEFAULT;
1288 
1289 	caps = cpuid_eax(IBS_CPUID_FEATURES);
1290 	if (!(caps & IBS_CAPS_AVAIL))
1291 		/* cpuid flags not valid */
1292 		return IBS_CAPS_DEFAULT;
1293 
1294 	return caps;
1295 }
1296 
get_ibs_caps(void)1297 u32 get_ibs_caps(void)
1298 {
1299 	return ibs_caps;
1300 }
1301 
1302 EXPORT_SYMBOL(get_ibs_caps);
1303 
get_eilvt(int offset)1304 static inline int get_eilvt(int offset)
1305 {
1306 	return !setup_APIC_eilvt(offset, 0, APIC_EILVT_MSG_NMI, 1);
1307 }
1308 
put_eilvt(int offset)1309 static inline int put_eilvt(int offset)
1310 {
1311 	return !setup_APIC_eilvt(offset, 0, 0, 1);
1312 }
1313 
1314 /*
1315  * Check and reserve APIC extended interrupt LVT offset for IBS if available.
1316  */
ibs_eilvt_valid(void)1317 static inline int ibs_eilvt_valid(void)
1318 {
1319 	int offset;
1320 	u64 val;
1321 	int valid = 0;
1322 
1323 	preempt_disable();
1324 
1325 	rdmsrl(MSR_AMD64_IBSCTL, val);
1326 	offset = val & IBSCTL_LVT_OFFSET_MASK;
1327 
1328 	if (!(val & IBSCTL_LVT_OFFSET_VALID)) {
1329 		pr_err(FW_BUG "cpu %d, invalid IBS interrupt offset %d (MSR%08X=0x%016llx)\n",
1330 		       smp_processor_id(), offset, MSR_AMD64_IBSCTL, val);
1331 		goto out;
1332 	}
1333 
1334 	if (!get_eilvt(offset)) {
1335 		pr_err(FW_BUG "cpu %d, IBS interrupt offset %d not available (MSR%08X=0x%016llx)\n",
1336 		       smp_processor_id(), offset, MSR_AMD64_IBSCTL, val);
1337 		goto out;
1338 	}
1339 
1340 	valid = 1;
1341 out:
1342 	preempt_enable();
1343 
1344 	return valid;
1345 }
1346 
setup_ibs_ctl(int ibs_eilvt_off)1347 static int setup_ibs_ctl(int ibs_eilvt_off)
1348 {
1349 	struct pci_dev *cpu_cfg;
1350 	int nodes;
1351 	u32 value = 0;
1352 
1353 	nodes = 0;
1354 	cpu_cfg = NULL;
1355 	do {
1356 		cpu_cfg = pci_get_device(PCI_VENDOR_ID_AMD,
1357 					 PCI_DEVICE_ID_AMD_10H_NB_MISC,
1358 					 cpu_cfg);
1359 		if (!cpu_cfg)
1360 			break;
1361 		++nodes;
1362 		pci_write_config_dword(cpu_cfg, IBSCTL, ibs_eilvt_off
1363 				       | IBSCTL_LVT_OFFSET_VALID);
1364 		pci_read_config_dword(cpu_cfg, IBSCTL, &value);
1365 		if (value != (ibs_eilvt_off | IBSCTL_LVT_OFFSET_VALID)) {
1366 			pci_dev_put(cpu_cfg);
1367 			pr_debug("Failed to setup IBS LVT offset, IBSCTL = 0x%08x\n",
1368 				 value);
1369 			return -EINVAL;
1370 		}
1371 	} while (1);
1372 
1373 	if (!nodes) {
1374 		pr_debug("No CPU node configured for IBS\n");
1375 		return -ENODEV;
1376 	}
1377 
1378 	return 0;
1379 }
1380 
1381 /*
1382  * This runs only on the current cpu. We try to find an LVT offset and
1383  * setup the local APIC. For this we must disable preemption. On
1384  * success we initialize all nodes with this offset. This updates then
1385  * the offset in the IBS_CTL per-node msr. The per-core APIC setup of
1386  * the IBS interrupt vector is handled by perf_ibs_cpu_notifier that
1387  * is using the new offset.
1388  */
force_ibs_eilvt_setup(void)1389 static void force_ibs_eilvt_setup(void)
1390 {
1391 	int offset;
1392 	int ret;
1393 
1394 	preempt_disable();
1395 	/* find the next free available EILVT entry, skip offset 0 */
1396 	for (offset = 1; offset < APIC_EILVT_NR_MAX; offset++) {
1397 		if (get_eilvt(offset))
1398 			break;
1399 	}
1400 	preempt_enable();
1401 
1402 	if (offset == APIC_EILVT_NR_MAX) {
1403 		pr_debug("No EILVT entry available\n");
1404 		return;
1405 	}
1406 
1407 	ret = setup_ibs_ctl(offset);
1408 	if (ret)
1409 		goto out;
1410 
1411 	if (!ibs_eilvt_valid())
1412 		goto out;
1413 
1414 	pr_info("LVT offset %d assigned\n", offset);
1415 
1416 	return;
1417 out:
1418 	preempt_disable();
1419 	put_eilvt(offset);
1420 	preempt_enable();
1421 	return;
1422 }
1423 
ibs_eilvt_setup(void)1424 static void ibs_eilvt_setup(void)
1425 {
1426 	/*
1427 	 * Force LVT offset assignment for family 10h: The offsets are
1428 	 * not assigned by the BIOS for this family, so the OS is
1429 	 * responsible for doing it. If the OS assignment fails, fall
1430 	 * back to BIOS settings and try to setup this.
1431 	 */
1432 	if (boot_cpu_data.x86 == 0x10)
1433 		force_ibs_eilvt_setup();
1434 }
1435 
get_ibs_lvt_offset(void)1436 static inline int get_ibs_lvt_offset(void)
1437 {
1438 	u64 val;
1439 
1440 	rdmsrl(MSR_AMD64_IBSCTL, val);
1441 	if (!(val & IBSCTL_LVT_OFFSET_VALID))
1442 		return -EINVAL;
1443 
1444 	return val & IBSCTL_LVT_OFFSET_MASK;
1445 }
1446 
setup_APIC_ibs(void)1447 static void setup_APIC_ibs(void)
1448 {
1449 	int offset;
1450 
1451 	offset = get_ibs_lvt_offset();
1452 	if (offset < 0)
1453 		goto failed;
1454 
1455 	if (!setup_APIC_eilvt(offset, 0, APIC_EILVT_MSG_NMI, 0))
1456 		return;
1457 failed:
1458 	pr_warn("perf: IBS APIC setup failed on cpu #%d\n",
1459 		smp_processor_id());
1460 }
1461 
clear_APIC_ibs(void)1462 static void clear_APIC_ibs(void)
1463 {
1464 	int offset;
1465 
1466 	offset = get_ibs_lvt_offset();
1467 	if (offset >= 0)
1468 		setup_APIC_eilvt(offset, 0, APIC_EILVT_MSG_FIX, 1);
1469 }
1470 
x86_pmu_amd_ibs_starting_cpu(unsigned int cpu)1471 static int x86_pmu_amd_ibs_starting_cpu(unsigned int cpu)
1472 {
1473 	setup_APIC_ibs();
1474 	return 0;
1475 }
1476 
1477 #ifdef CONFIG_PM
1478 
perf_ibs_suspend(void)1479 static int perf_ibs_suspend(void)
1480 {
1481 	clear_APIC_ibs();
1482 	return 0;
1483 }
1484 
perf_ibs_resume(void)1485 static void perf_ibs_resume(void)
1486 {
1487 	ibs_eilvt_setup();
1488 	setup_APIC_ibs();
1489 }
1490 
1491 static struct syscore_ops perf_ibs_syscore_ops = {
1492 	.resume		= perf_ibs_resume,
1493 	.suspend	= perf_ibs_suspend,
1494 };
1495 
perf_ibs_pm_init(void)1496 static void perf_ibs_pm_init(void)
1497 {
1498 	register_syscore_ops(&perf_ibs_syscore_ops);
1499 }
1500 
1501 #else
1502 
perf_ibs_pm_init(void)1503 static inline void perf_ibs_pm_init(void) { }
1504 
1505 #endif
1506 
x86_pmu_amd_ibs_dying_cpu(unsigned int cpu)1507 static int x86_pmu_amd_ibs_dying_cpu(unsigned int cpu)
1508 {
1509 	clear_APIC_ibs();
1510 	return 0;
1511 }
1512 
amd_ibs_init(void)1513 static __init int amd_ibs_init(void)
1514 {
1515 	u32 caps;
1516 
1517 	caps = __get_ibs_caps();
1518 	if (!caps)
1519 		return -ENODEV;	/* ibs not supported by the cpu */
1520 
1521 	ibs_eilvt_setup();
1522 
1523 	if (!ibs_eilvt_valid())
1524 		return -EINVAL;
1525 
1526 	perf_ibs_pm_init();
1527 
1528 	ibs_caps = caps;
1529 	/* make ibs_caps visible to other cpus: */
1530 	smp_mb();
1531 	/*
1532 	 * x86_pmu_amd_ibs_starting_cpu will be called from core on
1533 	 * all online cpus.
1534 	 */
1535 	cpuhp_setup_state(CPUHP_AP_PERF_X86_AMD_IBS_STARTING,
1536 			  "perf/x86/amd/ibs:starting",
1537 			  x86_pmu_amd_ibs_starting_cpu,
1538 			  x86_pmu_amd_ibs_dying_cpu);
1539 
1540 	return perf_event_ibs_init();
1541 }
1542 
1543 /* Since we need the pci subsystem to init ibs we can't do this earlier: */
1544 device_initcall(amd_ibs_init);
1545