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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 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 	if (has_branch_stack(event))
291 		return -EOPNOTSUPP;
292 
293 	ret = validate_group(event);
294 	if (ret)
295 		return ret;
296 
297 	if (hwc->sample_period) {
298 		if (config & perf_ibs->cnt_mask)
299 			/* raw max_cnt may not be set */
300 			return -EINVAL;
301 		if (!event->attr.sample_freq && hwc->sample_period & 0x0f)
302 			/*
303 			 * lower 4 bits can not be set in ibs max cnt,
304 			 * but allowing it in case we adjust the
305 			 * sample period to set a frequency.
306 			 */
307 			return -EINVAL;
308 		hwc->sample_period &= ~0x0FULL;
309 		if (!hwc->sample_period)
310 			hwc->sample_period = 0x10;
311 	} else {
312 		u64 period = 0;
313 
314 		if (perf_ibs == &perf_ibs_op) {
315 			period = (config & IBS_OP_MAX_CNT) << 4;
316 			if (ibs_caps & IBS_CAPS_OPCNTEXT)
317 				period |= config & IBS_OP_MAX_CNT_EXT_MASK;
318 		} else {
319 			period = (config & IBS_FETCH_MAX_CNT) << 4;
320 		}
321 
322 		config &= ~perf_ibs->cnt_mask;
323 		event->attr.sample_period = period;
324 		hwc->sample_period = period;
325 	}
326 
327 	if (!hwc->sample_period)
328 		return -EINVAL;
329 
330 	/*
331 	 * If we modify hwc->sample_period, we also need to update
332 	 * hwc->last_period and hwc->period_left.
333 	 */
334 	hwc->last_period = hwc->sample_period;
335 	local64_set(&hwc->period_left, hwc->sample_period);
336 
337 	hwc->config_base = perf_ibs->msr;
338 	hwc->config = config;
339 
340 	return 0;
341 }
342 
perf_ibs_set_period(struct perf_ibs * perf_ibs,struct hw_perf_event * hwc,u64 * period)343 static int perf_ibs_set_period(struct perf_ibs *perf_ibs,
344 			       struct hw_perf_event *hwc, u64 *period)
345 {
346 	int overflow;
347 
348 	/* ignore lower 4 bits in min count: */
349 	overflow = perf_event_set_period(hwc, 1<<4, perf_ibs->max_period, period);
350 	local64_set(&hwc->prev_count, 0);
351 
352 	return overflow;
353 }
354 
get_ibs_fetch_count(u64 config)355 static u64 get_ibs_fetch_count(u64 config)
356 {
357 	union ibs_fetch_ctl fetch_ctl = (union ibs_fetch_ctl)config;
358 
359 	return fetch_ctl.fetch_cnt << 4;
360 }
361 
get_ibs_op_count(u64 config)362 static u64 get_ibs_op_count(u64 config)
363 {
364 	union ibs_op_ctl op_ctl = (union ibs_op_ctl)config;
365 	u64 count = 0;
366 
367 	/*
368 	 * If the internal 27-bit counter rolled over, the count is MaxCnt
369 	 * and the lower 7 bits of CurCnt are randomized.
370 	 * Otherwise CurCnt has the full 27-bit current counter value.
371 	 */
372 	if (op_ctl.op_val) {
373 		count = op_ctl.opmaxcnt << 4;
374 		if (ibs_caps & IBS_CAPS_OPCNTEXT)
375 			count += op_ctl.opmaxcnt_ext << 20;
376 	} else if (ibs_caps & IBS_CAPS_RDWROPCNT) {
377 		count = op_ctl.opcurcnt;
378 	}
379 
380 	return count;
381 }
382 
383 static void
perf_ibs_event_update(struct perf_ibs * perf_ibs,struct perf_event * event,u64 * config)384 perf_ibs_event_update(struct perf_ibs *perf_ibs, struct perf_event *event,
385 		      u64 *config)
386 {
387 	u64 count = perf_ibs->get_count(*config);
388 
389 	/*
390 	 * Set width to 64 since we do not overflow on max width but
391 	 * instead on max count. In perf_ibs_set_period() we clear
392 	 * prev count manually on overflow.
393 	 */
394 	while (!perf_event_try_update(event, count, 64)) {
395 		rdmsrl(event->hw.config_base, *config);
396 		count = perf_ibs->get_count(*config);
397 	}
398 }
399 
perf_ibs_enable_event(struct perf_ibs * perf_ibs,struct hw_perf_event * hwc,u64 config)400 static inline void perf_ibs_enable_event(struct perf_ibs *perf_ibs,
401 					 struct hw_perf_event *hwc, u64 config)
402 {
403 	u64 tmp = hwc->config | config;
404 
405 	if (perf_ibs->fetch_count_reset_broken)
406 		wrmsrl(hwc->config_base, tmp & ~perf_ibs->enable_mask);
407 
408 	wrmsrl(hwc->config_base, tmp | perf_ibs->enable_mask);
409 }
410 
411 /*
412  * Erratum #420 Instruction-Based Sampling Engine May Generate
413  * Interrupt that Cannot Be Cleared:
414  *
415  * Must clear counter mask first, then clear the enable bit. See
416  * Revision Guide for AMD Family 10h Processors, Publication #41322.
417  */
perf_ibs_disable_event(struct perf_ibs * perf_ibs,struct hw_perf_event * hwc,u64 config)418 static inline void perf_ibs_disable_event(struct perf_ibs *perf_ibs,
419 					  struct hw_perf_event *hwc, u64 config)
420 {
421 	config &= ~perf_ibs->cnt_mask;
422 	if (boot_cpu_data.x86 == 0x10)
423 		wrmsrl(hwc->config_base, config);
424 	config &= ~perf_ibs->enable_mask;
425 	wrmsrl(hwc->config_base, config);
426 }
427 
428 /*
429  * We cannot restore the ibs pmu state, so we always needs to update
430  * the event while stopping it and then reset the state when starting
431  * again. Thus, ignoring PERF_EF_RELOAD and PERF_EF_UPDATE flags in
432  * perf_ibs_start()/perf_ibs_stop() and instead always do it.
433  */
perf_ibs_start(struct perf_event * event,int flags)434 static void perf_ibs_start(struct perf_event *event, int flags)
435 {
436 	struct hw_perf_event *hwc = &event->hw;
437 	struct perf_ibs *perf_ibs = container_of(event->pmu, struct perf_ibs, pmu);
438 	struct cpu_perf_ibs *pcpu = this_cpu_ptr(perf_ibs->pcpu);
439 	u64 period, config = 0;
440 
441 	if (WARN_ON_ONCE(!(hwc->state & PERF_HES_STOPPED)))
442 		return;
443 
444 	WARN_ON_ONCE(!(hwc->state & PERF_HES_UPTODATE));
445 	hwc->state = 0;
446 
447 	perf_ibs_set_period(perf_ibs, hwc, &period);
448 	if (perf_ibs == &perf_ibs_op && (ibs_caps & IBS_CAPS_OPCNTEXT)) {
449 		config |= period & IBS_OP_MAX_CNT_EXT_MASK;
450 		period &= ~IBS_OP_MAX_CNT_EXT_MASK;
451 	}
452 	config |= period >> 4;
453 
454 	/*
455 	 * Set STARTED before enabling the hardware, such that a subsequent NMI
456 	 * must observe it.
457 	 */
458 	set_bit(IBS_STARTED,    pcpu->state);
459 	clear_bit(IBS_STOPPING, pcpu->state);
460 	perf_ibs_enable_event(perf_ibs, hwc, config);
461 
462 	perf_event_update_userpage(event);
463 }
464 
perf_ibs_stop(struct perf_event * event,int flags)465 static void perf_ibs_stop(struct perf_event *event, int flags)
466 {
467 	struct hw_perf_event *hwc = &event->hw;
468 	struct perf_ibs *perf_ibs = container_of(event->pmu, struct perf_ibs, pmu);
469 	struct cpu_perf_ibs *pcpu = this_cpu_ptr(perf_ibs->pcpu);
470 	u64 config;
471 	int stopping;
472 
473 	if (test_and_set_bit(IBS_STOPPING, pcpu->state))
474 		return;
475 
476 	stopping = test_bit(IBS_STARTED, pcpu->state);
477 
478 	if (!stopping && (hwc->state & PERF_HES_UPTODATE))
479 		return;
480 
481 	rdmsrl(hwc->config_base, config);
482 
483 	if (stopping) {
484 		/*
485 		 * Set STOPPED before disabling the hardware, such that it
486 		 * must be visible to NMIs the moment we clear the EN bit,
487 		 * at which point we can generate an !VALID sample which
488 		 * we need to consume.
489 		 */
490 		set_bit(IBS_STOPPED, pcpu->state);
491 		perf_ibs_disable_event(perf_ibs, hwc, config);
492 		/*
493 		 * Clear STARTED after disabling the hardware; if it were
494 		 * cleared before an NMI hitting after the clear but before
495 		 * clearing the EN bit might think it a spurious NMI and not
496 		 * handle it.
497 		 *
498 		 * Clearing it after, however, creates the problem of the NMI
499 		 * handler seeing STARTED but not having a valid sample.
500 		 */
501 		clear_bit(IBS_STARTED, pcpu->state);
502 		WARN_ON_ONCE(hwc->state & PERF_HES_STOPPED);
503 		hwc->state |= PERF_HES_STOPPED;
504 	}
505 
506 	if (hwc->state & PERF_HES_UPTODATE)
507 		return;
508 
509 	/*
510 	 * Clear valid bit to not count rollovers on update, rollovers
511 	 * are only updated in the irq handler.
512 	 */
513 	config &= ~perf_ibs->valid_mask;
514 
515 	perf_ibs_event_update(perf_ibs, event, &config);
516 	hwc->state |= PERF_HES_UPTODATE;
517 }
518 
perf_ibs_add(struct perf_event * event,int flags)519 static int perf_ibs_add(struct perf_event *event, int flags)
520 {
521 	struct perf_ibs *perf_ibs = container_of(event->pmu, struct perf_ibs, pmu);
522 	struct cpu_perf_ibs *pcpu = this_cpu_ptr(perf_ibs->pcpu);
523 
524 	if (test_and_set_bit(IBS_ENABLED, pcpu->state))
525 		return -ENOSPC;
526 
527 	event->hw.state = PERF_HES_UPTODATE | PERF_HES_STOPPED;
528 
529 	pcpu->event = event;
530 
531 	if (flags & PERF_EF_START)
532 		perf_ibs_start(event, PERF_EF_RELOAD);
533 
534 	return 0;
535 }
536 
perf_ibs_del(struct perf_event * event,int flags)537 static void perf_ibs_del(struct perf_event *event, int flags)
538 {
539 	struct perf_ibs *perf_ibs = container_of(event->pmu, struct perf_ibs, pmu);
540 	struct cpu_perf_ibs *pcpu = this_cpu_ptr(perf_ibs->pcpu);
541 
542 	if (!test_and_clear_bit(IBS_ENABLED, pcpu->state))
543 		return;
544 
545 	perf_ibs_stop(event, PERF_EF_UPDATE);
546 
547 	pcpu->event = NULL;
548 
549 	perf_event_update_userpage(event);
550 }
551 
perf_ibs_read(struct perf_event * event)552 static void perf_ibs_read(struct perf_event *event) { }
553 
554 /*
555  * We need to initialize with empty group if all attributes in the
556  * group are dynamic.
557  */
558 static struct attribute *attrs_empty[] = {
559 	NULL,
560 };
561 
562 static struct attribute_group empty_format_group = {
563 	.name = "format",
564 	.attrs = attrs_empty,
565 };
566 
567 static struct attribute_group empty_caps_group = {
568 	.name = "caps",
569 	.attrs = attrs_empty,
570 };
571 
572 static const struct attribute_group *empty_attr_groups[] = {
573 	&empty_format_group,
574 	&empty_caps_group,
575 	NULL,
576 };
577 
578 PMU_FORMAT_ATTR(rand_en,	"config:57");
579 PMU_FORMAT_ATTR(cnt_ctl,	"config:19");
580 PMU_EVENT_ATTR_STRING(l3missonly, fetch_l3missonly, "config:59");
581 PMU_EVENT_ATTR_STRING(l3missonly, op_l3missonly, "config:16");
582 PMU_EVENT_ATTR_STRING(zen4_ibs_extensions, zen4_ibs_extensions, "1");
583 
584 static umode_t
zen4_ibs_extensions_is_visible(struct kobject * kobj,struct attribute * attr,int i)585 zen4_ibs_extensions_is_visible(struct kobject *kobj, struct attribute *attr, int i)
586 {
587 	return ibs_caps & IBS_CAPS_ZEN4 ? attr->mode : 0;
588 }
589 
590 static struct attribute *rand_en_attrs[] = {
591 	&format_attr_rand_en.attr,
592 	NULL,
593 };
594 
595 static struct attribute *fetch_l3missonly_attrs[] = {
596 	&fetch_l3missonly.attr.attr,
597 	NULL,
598 };
599 
600 static struct attribute *zen4_ibs_extensions_attrs[] = {
601 	&zen4_ibs_extensions.attr.attr,
602 	NULL,
603 };
604 
605 static struct attribute_group group_rand_en = {
606 	.name = "format",
607 	.attrs = rand_en_attrs,
608 };
609 
610 static struct attribute_group group_fetch_l3missonly = {
611 	.name = "format",
612 	.attrs = fetch_l3missonly_attrs,
613 	.is_visible = zen4_ibs_extensions_is_visible,
614 };
615 
616 static struct attribute_group group_zen4_ibs_extensions = {
617 	.name = "caps",
618 	.attrs = zen4_ibs_extensions_attrs,
619 	.is_visible = zen4_ibs_extensions_is_visible,
620 };
621 
622 static const struct attribute_group *fetch_attr_groups[] = {
623 	&group_rand_en,
624 	&empty_caps_group,
625 	NULL,
626 };
627 
628 static const struct attribute_group *fetch_attr_update[] = {
629 	&group_fetch_l3missonly,
630 	&group_zen4_ibs_extensions,
631 	NULL,
632 };
633 
634 static umode_t
cnt_ctl_is_visible(struct kobject * kobj,struct attribute * attr,int i)635 cnt_ctl_is_visible(struct kobject *kobj, struct attribute *attr, int i)
636 {
637 	return ibs_caps & IBS_CAPS_OPCNT ? attr->mode : 0;
638 }
639 
640 static struct attribute *cnt_ctl_attrs[] = {
641 	&format_attr_cnt_ctl.attr,
642 	NULL,
643 };
644 
645 static struct attribute *op_l3missonly_attrs[] = {
646 	&op_l3missonly.attr.attr,
647 	NULL,
648 };
649 
650 static struct attribute_group group_cnt_ctl = {
651 	.name = "format",
652 	.attrs = cnt_ctl_attrs,
653 	.is_visible = cnt_ctl_is_visible,
654 };
655 
656 static struct attribute_group group_op_l3missonly = {
657 	.name = "format",
658 	.attrs = op_l3missonly_attrs,
659 	.is_visible = zen4_ibs_extensions_is_visible,
660 };
661 
662 static const struct attribute_group *op_attr_update[] = {
663 	&group_cnt_ctl,
664 	&group_op_l3missonly,
665 	&group_zen4_ibs_extensions,
666 	NULL,
667 };
668 
669 static struct perf_ibs perf_ibs_fetch = {
670 	.pmu = {
671 		.task_ctx_nr	= perf_hw_context,
672 
673 		.event_init	= perf_ibs_init,
674 		.add		= perf_ibs_add,
675 		.del		= perf_ibs_del,
676 		.start		= perf_ibs_start,
677 		.stop		= perf_ibs_stop,
678 		.read		= perf_ibs_read,
679 		.capabilities	= PERF_PMU_CAP_NO_EXCLUDE,
680 	},
681 	.msr			= MSR_AMD64_IBSFETCHCTL,
682 	.config_mask		= IBS_FETCH_CONFIG_MASK,
683 	.cnt_mask		= IBS_FETCH_MAX_CNT,
684 	.enable_mask		= IBS_FETCH_ENABLE,
685 	.valid_mask		= IBS_FETCH_VAL,
686 	.max_period		= IBS_FETCH_MAX_CNT << 4,
687 	.offset_mask		= { MSR_AMD64_IBSFETCH_REG_MASK },
688 	.offset_max		= MSR_AMD64_IBSFETCH_REG_COUNT,
689 
690 	.get_count		= get_ibs_fetch_count,
691 };
692 
693 static struct perf_ibs perf_ibs_op = {
694 	.pmu = {
695 		.task_ctx_nr	= perf_hw_context,
696 
697 		.event_init	= perf_ibs_init,
698 		.add		= perf_ibs_add,
699 		.del		= perf_ibs_del,
700 		.start		= perf_ibs_start,
701 		.stop		= perf_ibs_stop,
702 		.read		= perf_ibs_read,
703 		.capabilities	= PERF_PMU_CAP_NO_EXCLUDE,
704 	},
705 	.msr			= MSR_AMD64_IBSOPCTL,
706 	.config_mask		= IBS_OP_CONFIG_MASK,
707 	.cnt_mask		= IBS_OP_MAX_CNT | IBS_OP_CUR_CNT |
708 				  IBS_OP_CUR_CNT_RAND,
709 	.enable_mask		= IBS_OP_ENABLE,
710 	.valid_mask		= IBS_OP_VAL,
711 	.max_period		= IBS_OP_MAX_CNT << 4,
712 	.offset_mask		= { MSR_AMD64_IBSOP_REG_MASK },
713 	.offset_max		= MSR_AMD64_IBSOP_REG_COUNT,
714 
715 	.get_count		= get_ibs_op_count,
716 };
717 
perf_ibs_get_mem_op(union ibs_op_data3 * op_data3,struct perf_sample_data * data)718 static void perf_ibs_get_mem_op(union ibs_op_data3 *op_data3,
719 				struct perf_sample_data *data)
720 {
721 	union perf_mem_data_src *data_src = &data->data_src;
722 
723 	data_src->mem_op = PERF_MEM_OP_NA;
724 
725 	if (op_data3->ld_op)
726 		data_src->mem_op = PERF_MEM_OP_LOAD;
727 	else if (op_data3->st_op)
728 		data_src->mem_op = PERF_MEM_OP_STORE;
729 }
730 
731 /*
732  * Processors having CPUID_Fn8000001B_EAX[11] aka IBS_CAPS_ZEN4 has
733  * more fine granular DataSrc encodings. Others have coarse.
734  */
perf_ibs_data_src(union ibs_op_data2 * op_data2)735 static u8 perf_ibs_data_src(union ibs_op_data2 *op_data2)
736 {
737 	if (ibs_caps & IBS_CAPS_ZEN4)
738 		return (op_data2->data_src_hi << 3) | op_data2->data_src_lo;
739 
740 	return op_data2->data_src_lo;
741 }
742 
743 #define	L(x)		(PERF_MEM_S(LVL, x) | PERF_MEM_S(LVL, HIT))
744 #define	LN(x)		PERF_MEM_S(LVLNUM, x)
745 #define	REM		PERF_MEM_S(REMOTE, REMOTE)
746 #define	HOPS(x)		PERF_MEM_S(HOPS, x)
747 
748 static u64 g_data_src[8] = {
749 	[IBS_DATA_SRC_LOC_CACHE]	  = L(L3) | L(REM_CCE1) | LN(ANY_CACHE) | HOPS(0),
750 	[IBS_DATA_SRC_DRAM]		  = L(LOC_RAM) | LN(RAM),
751 	[IBS_DATA_SRC_REM_CACHE]	  = L(REM_CCE2) | LN(ANY_CACHE) | REM | HOPS(1),
752 	[IBS_DATA_SRC_IO]		  = L(IO) | LN(IO),
753 };
754 
755 #define RMT_NODE_BITS			(1 << IBS_DATA_SRC_DRAM)
756 #define RMT_NODE_APPLICABLE(x)		(RMT_NODE_BITS & (1 << x))
757 
758 static u64 g_zen4_data_src[32] = {
759 	[IBS_DATA_SRC_EXT_LOC_CACHE]	  = L(L3) | LN(L3),
760 	[IBS_DATA_SRC_EXT_NEAR_CCX_CACHE] = L(REM_CCE1) | LN(ANY_CACHE) | REM | HOPS(0),
761 	[IBS_DATA_SRC_EXT_DRAM]		  = L(LOC_RAM) | LN(RAM),
762 	[IBS_DATA_SRC_EXT_FAR_CCX_CACHE]  = L(REM_CCE2) | LN(ANY_CACHE) | REM | HOPS(1),
763 	[IBS_DATA_SRC_EXT_PMEM]		  = LN(PMEM),
764 	[IBS_DATA_SRC_EXT_IO]		  = L(IO) | LN(IO),
765 	[IBS_DATA_SRC_EXT_EXT_MEM]	  = LN(CXL),
766 };
767 
768 #define ZEN4_RMT_NODE_BITS		((1 << IBS_DATA_SRC_EXT_DRAM) | \
769 					 (1 << IBS_DATA_SRC_EXT_PMEM) | \
770 					 (1 << IBS_DATA_SRC_EXT_EXT_MEM))
771 #define ZEN4_RMT_NODE_APPLICABLE(x)	(ZEN4_RMT_NODE_BITS & (1 << x))
772 
perf_ibs_get_mem_lvl(union ibs_op_data2 * op_data2,union ibs_op_data3 * op_data3,struct perf_sample_data * data)773 static __u64 perf_ibs_get_mem_lvl(union ibs_op_data2 *op_data2,
774 				  union ibs_op_data3 *op_data3,
775 				  struct perf_sample_data *data)
776 {
777 	union perf_mem_data_src *data_src = &data->data_src;
778 	u8 ibs_data_src = perf_ibs_data_src(op_data2);
779 
780 	data_src->mem_lvl = 0;
781 	data_src->mem_lvl_num = 0;
782 
783 	/*
784 	 * DcMiss, L2Miss, DataSrc, DcMissLat etc. are all invalid for Uncached
785 	 * memory accesses. So, check DcUcMemAcc bit early.
786 	 */
787 	if (op_data3->dc_uc_mem_acc && ibs_data_src != IBS_DATA_SRC_EXT_IO)
788 		return L(UNC) | LN(UNC);
789 
790 	/* L1 Hit */
791 	if (op_data3->dc_miss == 0)
792 		return L(L1) | LN(L1);
793 
794 	/* L2 Hit */
795 	if (op_data3->l2_miss == 0) {
796 		/* Erratum #1293 */
797 		if (boot_cpu_data.x86 != 0x19 || boot_cpu_data.x86_model > 0xF ||
798 		    !(op_data3->sw_pf || op_data3->dc_miss_no_mab_alloc))
799 			return L(L2) | LN(L2);
800 	}
801 
802 	/*
803 	 * OP_DATA2 is valid only for load ops. Skip all checks which
804 	 * uses OP_DATA2[DataSrc].
805 	 */
806 	if (data_src->mem_op != PERF_MEM_OP_LOAD)
807 		goto check_mab;
808 
809 	if (ibs_caps & IBS_CAPS_ZEN4) {
810 		u64 val = g_zen4_data_src[ibs_data_src];
811 
812 		if (!val)
813 			goto check_mab;
814 
815 		/* HOPS_1 because IBS doesn't provide remote socket detail */
816 		if (op_data2->rmt_node && ZEN4_RMT_NODE_APPLICABLE(ibs_data_src)) {
817 			if (ibs_data_src == IBS_DATA_SRC_EXT_DRAM)
818 				val = L(REM_RAM1) | LN(RAM) | REM | HOPS(1);
819 			else
820 				val |= REM | HOPS(1);
821 		}
822 
823 		return val;
824 	} else {
825 		u64 val = g_data_src[ibs_data_src];
826 
827 		if (!val)
828 			goto check_mab;
829 
830 		/* HOPS_1 because IBS doesn't provide remote socket detail */
831 		if (op_data2->rmt_node && RMT_NODE_APPLICABLE(ibs_data_src)) {
832 			if (ibs_data_src == IBS_DATA_SRC_DRAM)
833 				val = L(REM_RAM1) | LN(RAM) | REM | HOPS(1);
834 			else
835 				val |= REM | HOPS(1);
836 		}
837 
838 		return val;
839 	}
840 
841 check_mab:
842 	/*
843 	 * MAB (Miss Address Buffer) Hit. MAB keeps track of outstanding
844 	 * DC misses. However, such data may come from any level in mem
845 	 * hierarchy. IBS provides detail about both MAB as well as actual
846 	 * DataSrc simultaneously. Prioritize DataSrc over MAB, i.e. set
847 	 * MAB only when IBS fails to provide DataSrc.
848 	 */
849 	if (op_data3->dc_miss_no_mab_alloc)
850 		return L(LFB) | LN(LFB);
851 
852 	/* Don't set HIT with NA */
853 	return PERF_MEM_S(LVL, NA) | LN(NA);
854 }
855 
perf_ibs_cache_hit_st_valid(void)856 static bool perf_ibs_cache_hit_st_valid(void)
857 {
858 	/* 0: Uninitialized, 1: Valid, -1: Invalid */
859 	static int cache_hit_st_valid;
860 
861 	if (unlikely(!cache_hit_st_valid)) {
862 		if (boot_cpu_data.x86 == 0x19 &&
863 		    (boot_cpu_data.x86_model <= 0xF ||
864 		    (boot_cpu_data.x86_model >= 0x20 &&
865 		     boot_cpu_data.x86_model <= 0x5F))) {
866 			cache_hit_st_valid = -1;
867 		} else {
868 			cache_hit_st_valid = 1;
869 		}
870 	}
871 
872 	return cache_hit_st_valid == 1;
873 }
874 
perf_ibs_get_mem_snoop(union ibs_op_data2 * op_data2,struct perf_sample_data * data)875 static void perf_ibs_get_mem_snoop(union ibs_op_data2 *op_data2,
876 				   struct perf_sample_data *data)
877 {
878 	union perf_mem_data_src *data_src = &data->data_src;
879 	u8 ibs_data_src;
880 
881 	data_src->mem_snoop = PERF_MEM_SNOOP_NA;
882 
883 	if (!perf_ibs_cache_hit_st_valid() ||
884 	    data_src->mem_op != PERF_MEM_OP_LOAD ||
885 	    data_src->mem_lvl & PERF_MEM_LVL_L1 ||
886 	    data_src->mem_lvl & PERF_MEM_LVL_L2 ||
887 	    op_data2->cache_hit_st)
888 		return;
889 
890 	ibs_data_src = perf_ibs_data_src(op_data2);
891 
892 	if (ibs_caps & IBS_CAPS_ZEN4) {
893 		if (ibs_data_src == IBS_DATA_SRC_EXT_LOC_CACHE ||
894 		    ibs_data_src == IBS_DATA_SRC_EXT_NEAR_CCX_CACHE ||
895 		    ibs_data_src == IBS_DATA_SRC_EXT_FAR_CCX_CACHE)
896 			data_src->mem_snoop = PERF_MEM_SNOOP_HITM;
897 	} else if (ibs_data_src == IBS_DATA_SRC_LOC_CACHE) {
898 		data_src->mem_snoop = PERF_MEM_SNOOP_HITM;
899 	}
900 }
901 
perf_ibs_get_tlb_lvl(union ibs_op_data3 * op_data3,struct perf_sample_data * data)902 static void perf_ibs_get_tlb_lvl(union ibs_op_data3 *op_data3,
903 				 struct perf_sample_data *data)
904 {
905 	union perf_mem_data_src *data_src = &data->data_src;
906 
907 	data_src->mem_dtlb = PERF_MEM_TLB_NA;
908 
909 	if (!op_data3->dc_lin_addr_valid)
910 		return;
911 
912 	if (!op_data3->dc_l1tlb_miss) {
913 		data_src->mem_dtlb = PERF_MEM_TLB_L1 | PERF_MEM_TLB_HIT;
914 		return;
915 	}
916 
917 	if (!op_data3->dc_l2tlb_miss) {
918 		data_src->mem_dtlb = PERF_MEM_TLB_L2 | PERF_MEM_TLB_HIT;
919 		return;
920 	}
921 
922 	data_src->mem_dtlb = PERF_MEM_TLB_L2 | PERF_MEM_TLB_MISS;
923 }
924 
perf_ibs_get_mem_lock(union ibs_op_data3 * op_data3,struct perf_sample_data * data)925 static void perf_ibs_get_mem_lock(union ibs_op_data3 *op_data3,
926 				  struct perf_sample_data *data)
927 {
928 	union perf_mem_data_src *data_src = &data->data_src;
929 
930 	data_src->mem_lock = PERF_MEM_LOCK_NA;
931 
932 	if (op_data3->dc_locked_op)
933 		data_src->mem_lock = PERF_MEM_LOCK_LOCKED;
934 }
935 
936 #define ibs_op_msr_idx(msr)	(msr - MSR_AMD64_IBSOPCTL)
937 
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)938 static void perf_ibs_get_data_src(struct perf_ibs_data *ibs_data,
939 				  struct perf_sample_data *data,
940 				  union ibs_op_data2 *op_data2,
941 				  union ibs_op_data3 *op_data3)
942 {
943 	union perf_mem_data_src *data_src = &data->data_src;
944 
945 	data_src->val |= perf_ibs_get_mem_lvl(op_data2, op_data3, data);
946 	perf_ibs_get_mem_snoop(op_data2, data);
947 	perf_ibs_get_tlb_lvl(op_data3, data);
948 	perf_ibs_get_mem_lock(op_data3, data);
949 }
950 
perf_ibs_get_op_data2(struct perf_ibs_data * ibs_data,union ibs_op_data3 * op_data3)951 static __u64 perf_ibs_get_op_data2(struct perf_ibs_data *ibs_data,
952 				   union ibs_op_data3 *op_data3)
953 {
954 	__u64 val = ibs_data->regs[ibs_op_msr_idx(MSR_AMD64_IBSOPDATA2)];
955 
956 	/* Erratum #1293 */
957 	if (boot_cpu_data.x86 == 0x19 && boot_cpu_data.x86_model <= 0xF &&
958 	    (op_data3->sw_pf || op_data3->dc_miss_no_mab_alloc)) {
959 		/*
960 		 * OP_DATA2 has only two fields on Zen3: DataSrc and RmtNode.
961 		 * DataSrc=0 is 'No valid status' and RmtNode is invalid when
962 		 * DataSrc=0.
963 		 */
964 		val = 0;
965 	}
966 	return val;
967 }
968 
perf_ibs_parse_ld_st_data(__u64 sample_type,struct perf_ibs_data * ibs_data,struct perf_sample_data * data)969 static void perf_ibs_parse_ld_st_data(__u64 sample_type,
970 				      struct perf_ibs_data *ibs_data,
971 				      struct perf_sample_data *data)
972 {
973 	union ibs_op_data3 op_data3;
974 	union ibs_op_data2 op_data2;
975 	union ibs_op_data op_data;
976 
977 	data->data_src.val = PERF_MEM_NA;
978 	op_data3.val = ibs_data->regs[ibs_op_msr_idx(MSR_AMD64_IBSOPDATA3)];
979 
980 	perf_ibs_get_mem_op(&op_data3, data);
981 	if (data->data_src.mem_op != PERF_MEM_OP_LOAD &&
982 	    data->data_src.mem_op != PERF_MEM_OP_STORE)
983 		return;
984 
985 	op_data2.val = perf_ibs_get_op_data2(ibs_data, &op_data3);
986 
987 	if (sample_type & PERF_SAMPLE_DATA_SRC) {
988 		perf_ibs_get_data_src(ibs_data, data, &op_data2, &op_data3);
989 		data->sample_flags |= PERF_SAMPLE_DATA_SRC;
990 	}
991 
992 	if (sample_type & PERF_SAMPLE_WEIGHT_TYPE && op_data3.dc_miss &&
993 	    data->data_src.mem_op == PERF_MEM_OP_LOAD) {
994 		op_data.val = ibs_data->regs[ibs_op_msr_idx(MSR_AMD64_IBSOPDATA)];
995 
996 		if (sample_type & PERF_SAMPLE_WEIGHT_STRUCT) {
997 			data->weight.var1_dw = op_data3.dc_miss_lat;
998 			data->weight.var2_w = op_data.tag_to_ret_ctr;
999 		} else if (sample_type & PERF_SAMPLE_WEIGHT) {
1000 			data->weight.full = op_data3.dc_miss_lat;
1001 		}
1002 		data->sample_flags |= PERF_SAMPLE_WEIGHT_TYPE;
1003 	}
1004 
1005 	if (sample_type & PERF_SAMPLE_ADDR && op_data3.dc_lin_addr_valid) {
1006 		data->addr = ibs_data->regs[ibs_op_msr_idx(MSR_AMD64_IBSDCLINAD)];
1007 		data->sample_flags |= PERF_SAMPLE_ADDR;
1008 	}
1009 
1010 	if (sample_type & PERF_SAMPLE_PHYS_ADDR && op_data3.dc_phy_addr_valid) {
1011 		data->phys_addr = ibs_data->regs[ibs_op_msr_idx(MSR_AMD64_IBSDCPHYSAD)];
1012 		data->sample_flags |= PERF_SAMPLE_PHYS_ADDR;
1013 	}
1014 }
1015 
perf_ibs_get_offset_max(struct perf_ibs * perf_ibs,u64 sample_type,int check_rip)1016 static int perf_ibs_get_offset_max(struct perf_ibs *perf_ibs, u64 sample_type,
1017 				   int check_rip)
1018 {
1019 	if (sample_type & PERF_SAMPLE_RAW ||
1020 	    (perf_ibs == &perf_ibs_op &&
1021 	     (sample_type & PERF_SAMPLE_DATA_SRC ||
1022 	      sample_type & PERF_SAMPLE_WEIGHT_TYPE ||
1023 	      sample_type & PERF_SAMPLE_ADDR ||
1024 	      sample_type & PERF_SAMPLE_PHYS_ADDR)))
1025 		return perf_ibs->offset_max;
1026 	else if (check_rip)
1027 		return 3;
1028 	return 1;
1029 }
1030 
perf_ibs_handle_irq(struct perf_ibs * perf_ibs,struct pt_regs * iregs)1031 static int perf_ibs_handle_irq(struct perf_ibs *perf_ibs, struct pt_regs *iregs)
1032 {
1033 	struct cpu_perf_ibs *pcpu = this_cpu_ptr(perf_ibs->pcpu);
1034 	struct perf_event *event = pcpu->event;
1035 	struct hw_perf_event *hwc;
1036 	struct perf_sample_data data;
1037 	struct perf_raw_record raw;
1038 	struct pt_regs regs;
1039 	struct perf_ibs_data ibs_data;
1040 	int offset, size, check_rip, offset_max, throttle = 0;
1041 	unsigned int msr;
1042 	u64 *buf, *config, period, new_config = 0;
1043 
1044 	if (!test_bit(IBS_STARTED, pcpu->state)) {
1045 fail:
1046 		/*
1047 		 * Catch spurious interrupts after stopping IBS: After
1048 		 * disabling IBS there could be still incoming NMIs
1049 		 * with samples that even have the valid bit cleared.
1050 		 * Mark all this NMIs as handled.
1051 		 */
1052 		if (test_and_clear_bit(IBS_STOPPED, pcpu->state))
1053 			return 1;
1054 
1055 		return 0;
1056 	}
1057 
1058 	if (WARN_ON_ONCE(!event))
1059 		goto fail;
1060 
1061 	hwc = &event->hw;
1062 	msr = hwc->config_base;
1063 	buf = ibs_data.regs;
1064 	rdmsrl(msr, *buf);
1065 	if (!(*buf++ & perf_ibs->valid_mask))
1066 		goto fail;
1067 
1068 	config = &ibs_data.regs[0];
1069 	perf_ibs_event_update(perf_ibs, event, config);
1070 	perf_sample_data_init(&data, 0, hwc->last_period);
1071 	if (!perf_ibs_set_period(perf_ibs, hwc, &period))
1072 		goto out;	/* no sw counter overflow */
1073 
1074 	ibs_data.caps = ibs_caps;
1075 	size = 1;
1076 	offset = 1;
1077 	check_rip = (perf_ibs == &perf_ibs_op && (ibs_caps & IBS_CAPS_RIPINVALIDCHK));
1078 
1079 	offset_max = perf_ibs_get_offset_max(perf_ibs, event->attr.sample_type, check_rip);
1080 
1081 	do {
1082 		rdmsrl(msr + offset, *buf++);
1083 		size++;
1084 		offset = find_next_bit(perf_ibs->offset_mask,
1085 				       perf_ibs->offset_max,
1086 				       offset + 1);
1087 	} while (offset < offset_max);
1088 	/*
1089 	 * Read IbsBrTarget, IbsOpData4, and IbsExtdCtl separately
1090 	 * depending on their availability.
1091 	 * Can't add to offset_max as they are staggered
1092 	 */
1093 	if (event->attr.sample_type & PERF_SAMPLE_RAW) {
1094 		if (perf_ibs == &perf_ibs_op) {
1095 			if (ibs_caps & IBS_CAPS_BRNTRGT) {
1096 				rdmsrl(MSR_AMD64_IBSBRTARGET, *buf++);
1097 				size++;
1098 			}
1099 			if (ibs_caps & IBS_CAPS_OPDATA4) {
1100 				rdmsrl(MSR_AMD64_IBSOPDATA4, *buf++);
1101 				size++;
1102 			}
1103 		}
1104 		if (perf_ibs == &perf_ibs_fetch && (ibs_caps & IBS_CAPS_FETCHCTLEXTD)) {
1105 			rdmsrl(MSR_AMD64_ICIBSEXTDCTL, *buf++);
1106 			size++;
1107 		}
1108 	}
1109 	ibs_data.size = sizeof(u64) * size;
1110 
1111 	regs = *iregs;
1112 	if (check_rip && (ibs_data.regs[2] & IBS_RIP_INVALID)) {
1113 		regs.flags &= ~PERF_EFLAGS_EXACT;
1114 	} else {
1115 		/* Workaround for erratum #1197 */
1116 		if (perf_ibs->fetch_ignore_if_zero_rip && !(ibs_data.regs[1]))
1117 			goto out;
1118 
1119 		set_linear_ip(&regs, ibs_data.regs[1]);
1120 		regs.flags |= PERF_EFLAGS_EXACT;
1121 	}
1122 
1123 	if (event->attr.sample_type & PERF_SAMPLE_RAW) {
1124 		raw = (struct perf_raw_record){
1125 			.frag = {
1126 				.size = sizeof(u32) + ibs_data.size,
1127 				.data = ibs_data.data,
1128 			},
1129 		};
1130 		perf_sample_save_raw_data(&data, event, &raw);
1131 	}
1132 
1133 	if (perf_ibs == &perf_ibs_op)
1134 		perf_ibs_parse_ld_st_data(event->attr.sample_type, &ibs_data, &data);
1135 
1136 	/*
1137 	 * rip recorded by IbsOpRip will not be consistent with rsp and rbp
1138 	 * recorded as part of interrupt regs. Thus we need to use rip from
1139 	 * interrupt regs while unwinding call stack.
1140 	 */
1141 	if (event->attr.sample_type & PERF_SAMPLE_CALLCHAIN)
1142 		perf_sample_save_callchain(&data, event, iregs);
1143 
1144 	throttle = perf_event_overflow(event, &data, &regs);
1145 out:
1146 	if (throttle) {
1147 		perf_ibs_stop(event, 0);
1148 	} else {
1149 		if (perf_ibs == &perf_ibs_op) {
1150 			if (ibs_caps & IBS_CAPS_OPCNTEXT) {
1151 				new_config = period & IBS_OP_MAX_CNT_EXT_MASK;
1152 				period &= ~IBS_OP_MAX_CNT_EXT_MASK;
1153 			}
1154 			if ((ibs_caps & IBS_CAPS_RDWROPCNT) && (*config & IBS_OP_CNT_CTL))
1155 				new_config |= *config & IBS_OP_CUR_CNT_RAND;
1156 		}
1157 		new_config |= period >> 4;
1158 
1159 		perf_ibs_enable_event(perf_ibs, hwc, new_config);
1160 	}
1161 
1162 	perf_event_update_userpage(event);
1163 
1164 	return 1;
1165 }
1166 
1167 static int
perf_ibs_nmi_handler(unsigned int cmd,struct pt_regs * regs)1168 perf_ibs_nmi_handler(unsigned int cmd, struct pt_regs *regs)
1169 {
1170 	u64 stamp = sched_clock();
1171 	int handled = 0;
1172 
1173 	handled += perf_ibs_handle_irq(&perf_ibs_fetch, regs);
1174 	handled += perf_ibs_handle_irq(&perf_ibs_op, regs);
1175 
1176 	if (handled)
1177 		inc_irq_stat(apic_perf_irqs);
1178 
1179 	perf_sample_event_took(sched_clock() - stamp);
1180 
1181 	return handled;
1182 }
1183 NOKPROBE_SYMBOL(perf_ibs_nmi_handler);
1184 
perf_ibs_pmu_init(struct perf_ibs * perf_ibs,char * name)1185 static __init int perf_ibs_pmu_init(struct perf_ibs *perf_ibs, char *name)
1186 {
1187 	struct cpu_perf_ibs __percpu *pcpu;
1188 	int ret;
1189 
1190 	pcpu = alloc_percpu(struct cpu_perf_ibs);
1191 	if (!pcpu)
1192 		return -ENOMEM;
1193 
1194 	perf_ibs->pcpu = pcpu;
1195 
1196 	ret = perf_pmu_register(&perf_ibs->pmu, name, -1);
1197 	if (ret) {
1198 		perf_ibs->pcpu = NULL;
1199 		free_percpu(pcpu);
1200 	}
1201 
1202 	return ret;
1203 }
1204 
perf_ibs_fetch_init(void)1205 static __init int perf_ibs_fetch_init(void)
1206 {
1207 	/*
1208 	 * Some chips fail to reset the fetch count when it is written; instead
1209 	 * they need a 0-1 transition of IbsFetchEn.
1210 	 */
1211 	if (boot_cpu_data.x86 >= 0x16 && boot_cpu_data.x86 <= 0x18)
1212 		perf_ibs_fetch.fetch_count_reset_broken = 1;
1213 
1214 	if (boot_cpu_data.x86 == 0x19 && boot_cpu_data.x86_model < 0x10)
1215 		perf_ibs_fetch.fetch_ignore_if_zero_rip = 1;
1216 
1217 	if (ibs_caps & IBS_CAPS_ZEN4)
1218 		perf_ibs_fetch.config_mask |= IBS_FETCH_L3MISSONLY;
1219 
1220 	perf_ibs_fetch.pmu.attr_groups = fetch_attr_groups;
1221 	perf_ibs_fetch.pmu.attr_update = fetch_attr_update;
1222 
1223 	return perf_ibs_pmu_init(&perf_ibs_fetch, "ibs_fetch");
1224 }
1225 
perf_ibs_op_init(void)1226 static __init int perf_ibs_op_init(void)
1227 {
1228 	if (ibs_caps & IBS_CAPS_OPCNT)
1229 		perf_ibs_op.config_mask |= IBS_OP_CNT_CTL;
1230 
1231 	if (ibs_caps & IBS_CAPS_OPCNTEXT) {
1232 		perf_ibs_op.max_period  |= IBS_OP_MAX_CNT_EXT_MASK;
1233 		perf_ibs_op.config_mask	|= IBS_OP_MAX_CNT_EXT_MASK;
1234 		perf_ibs_op.cnt_mask    |= (IBS_OP_MAX_CNT_EXT_MASK |
1235 					    IBS_OP_CUR_CNT_EXT_MASK);
1236 	}
1237 
1238 	if (ibs_caps & IBS_CAPS_ZEN4)
1239 		perf_ibs_op.config_mask |= IBS_OP_L3MISSONLY;
1240 
1241 	perf_ibs_op.pmu.attr_groups = empty_attr_groups;
1242 	perf_ibs_op.pmu.attr_update = op_attr_update;
1243 
1244 	return perf_ibs_pmu_init(&perf_ibs_op, "ibs_op");
1245 }
1246 
perf_event_ibs_init(void)1247 static __init int perf_event_ibs_init(void)
1248 {
1249 	int ret;
1250 
1251 	ret = perf_ibs_fetch_init();
1252 	if (ret)
1253 		return ret;
1254 
1255 	ret = perf_ibs_op_init();
1256 	if (ret)
1257 		goto err_op;
1258 
1259 	ret = register_nmi_handler(NMI_LOCAL, perf_ibs_nmi_handler, 0, "perf_ibs");
1260 	if (ret)
1261 		goto err_nmi;
1262 
1263 	pr_info("perf: AMD IBS detected (0x%08x)\n", ibs_caps);
1264 	return 0;
1265 
1266 err_nmi:
1267 	perf_pmu_unregister(&perf_ibs_op.pmu);
1268 	free_percpu(perf_ibs_op.pcpu);
1269 	perf_ibs_op.pcpu = NULL;
1270 err_op:
1271 	perf_pmu_unregister(&perf_ibs_fetch.pmu);
1272 	free_percpu(perf_ibs_fetch.pcpu);
1273 	perf_ibs_fetch.pcpu = NULL;
1274 
1275 	return ret;
1276 }
1277 
1278 #else /* defined(CONFIG_PERF_EVENTS) && defined(CONFIG_CPU_SUP_AMD) */
1279 
perf_event_ibs_init(void)1280 static __init int perf_event_ibs_init(void)
1281 {
1282 	return 0;
1283 }
1284 
1285 #endif
1286 
1287 /* IBS - apic initialization, for perf and oprofile */
1288 
__get_ibs_caps(void)1289 static __init u32 __get_ibs_caps(void)
1290 {
1291 	u32 caps;
1292 	unsigned int max_level;
1293 
1294 	if (!boot_cpu_has(X86_FEATURE_IBS))
1295 		return 0;
1296 
1297 	/* check IBS cpuid feature flags */
1298 	max_level = cpuid_eax(0x80000000);
1299 	if (max_level < IBS_CPUID_FEATURES)
1300 		return IBS_CAPS_DEFAULT;
1301 
1302 	caps = cpuid_eax(IBS_CPUID_FEATURES);
1303 	if (!(caps & IBS_CAPS_AVAIL))
1304 		/* cpuid flags not valid */
1305 		return IBS_CAPS_DEFAULT;
1306 
1307 	return caps;
1308 }
1309 
get_ibs_caps(void)1310 u32 get_ibs_caps(void)
1311 {
1312 	return ibs_caps;
1313 }
1314 
1315 EXPORT_SYMBOL(get_ibs_caps);
1316 
get_eilvt(int offset)1317 static inline int get_eilvt(int offset)
1318 {
1319 	return !setup_APIC_eilvt(offset, 0, APIC_EILVT_MSG_NMI, 1);
1320 }
1321 
put_eilvt(int offset)1322 static inline int put_eilvt(int offset)
1323 {
1324 	return !setup_APIC_eilvt(offset, 0, 0, 1);
1325 }
1326 
1327 /*
1328  * Check and reserve APIC extended interrupt LVT offset for IBS if available.
1329  */
ibs_eilvt_valid(void)1330 static inline int ibs_eilvt_valid(void)
1331 {
1332 	int offset;
1333 	u64 val;
1334 	int valid = 0;
1335 
1336 	preempt_disable();
1337 
1338 	rdmsrl(MSR_AMD64_IBSCTL, val);
1339 	offset = val & IBSCTL_LVT_OFFSET_MASK;
1340 
1341 	if (!(val & IBSCTL_LVT_OFFSET_VALID)) {
1342 		pr_err(FW_BUG "cpu %d, invalid IBS interrupt offset %d (MSR%08X=0x%016llx)\n",
1343 		       smp_processor_id(), offset, MSR_AMD64_IBSCTL, val);
1344 		goto out;
1345 	}
1346 
1347 	if (!get_eilvt(offset)) {
1348 		pr_err(FW_BUG "cpu %d, IBS interrupt offset %d not available (MSR%08X=0x%016llx)\n",
1349 		       smp_processor_id(), offset, MSR_AMD64_IBSCTL, val);
1350 		goto out;
1351 	}
1352 
1353 	valid = 1;
1354 out:
1355 	preempt_enable();
1356 
1357 	return valid;
1358 }
1359 
setup_ibs_ctl(int ibs_eilvt_off)1360 static int setup_ibs_ctl(int ibs_eilvt_off)
1361 {
1362 	struct pci_dev *cpu_cfg;
1363 	int nodes;
1364 	u32 value = 0;
1365 
1366 	nodes = 0;
1367 	cpu_cfg = NULL;
1368 	do {
1369 		cpu_cfg = pci_get_device(PCI_VENDOR_ID_AMD,
1370 					 PCI_DEVICE_ID_AMD_10H_NB_MISC,
1371 					 cpu_cfg);
1372 		if (!cpu_cfg)
1373 			break;
1374 		++nodes;
1375 		pci_write_config_dword(cpu_cfg, IBSCTL, ibs_eilvt_off
1376 				       | IBSCTL_LVT_OFFSET_VALID);
1377 		pci_read_config_dword(cpu_cfg, IBSCTL, &value);
1378 		if (value != (ibs_eilvt_off | IBSCTL_LVT_OFFSET_VALID)) {
1379 			pci_dev_put(cpu_cfg);
1380 			pr_debug("Failed to setup IBS LVT offset, IBSCTL = 0x%08x\n",
1381 				 value);
1382 			return -EINVAL;
1383 		}
1384 	} while (1);
1385 
1386 	if (!nodes) {
1387 		pr_debug("No CPU node configured for IBS\n");
1388 		return -ENODEV;
1389 	}
1390 
1391 	return 0;
1392 }
1393 
1394 /*
1395  * This runs only on the current cpu. We try to find an LVT offset and
1396  * setup the local APIC. For this we must disable preemption. On
1397  * success we initialize all nodes with this offset. This updates then
1398  * the offset in the IBS_CTL per-node msr. The per-core APIC setup of
1399  * the IBS interrupt vector is handled by perf_ibs_cpu_notifier that
1400  * is using the new offset.
1401  */
force_ibs_eilvt_setup(void)1402 static void force_ibs_eilvt_setup(void)
1403 {
1404 	int offset;
1405 	int ret;
1406 
1407 	preempt_disable();
1408 	/* find the next free available EILVT entry, skip offset 0 */
1409 	for (offset = 1; offset < APIC_EILVT_NR_MAX; offset++) {
1410 		if (get_eilvt(offset))
1411 			break;
1412 	}
1413 	preempt_enable();
1414 
1415 	if (offset == APIC_EILVT_NR_MAX) {
1416 		pr_debug("No EILVT entry available\n");
1417 		return;
1418 	}
1419 
1420 	ret = setup_ibs_ctl(offset);
1421 	if (ret)
1422 		goto out;
1423 
1424 	if (!ibs_eilvt_valid())
1425 		goto out;
1426 
1427 	pr_info("LVT offset %d assigned\n", offset);
1428 
1429 	return;
1430 out:
1431 	preempt_disable();
1432 	put_eilvt(offset);
1433 	preempt_enable();
1434 	return;
1435 }
1436 
ibs_eilvt_setup(void)1437 static void ibs_eilvt_setup(void)
1438 {
1439 	/*
1440 	 * Force LVT offset assignment for family 10h: The offsets are
1441 	 * not assigned by the BIOS for this family, so the OS is
1442 	 * responsible for doing it. If the OS assignment fails, fall
1443 	 * back to BIOS settings and try to setup this.
1444 	 */
1445 	if (boot_cpu_data.x86 == 0x10)
1446 		force_ibs_eilvt_setup();
1447 }
1448 
get_ibs_lvt_offset(void)1449 static inline int get_ibs_lvt_offset(void)
1450 {
1451 	u64 val;
1452 
1453 	rdmsrl(MSR_AMD64_IBSCTL, val);
1454 	if (!(val & IBSCTL_LVT_OFFSET_VALID))
1455 		return -EINVAL;
1456 
1457 	return val & IBSCTL_LVT_OFFSET_MASK;
1458 }
1459 
setup_APIC_ibs(void)1460 static void setup_APIC_ibs(void)
1461 {
1462 	int offset;
1463 
1464 	offset = get_ibs_lvt_offset();
1465 	if (offset < 0)
1466 		goto failed;
1467 
1468 	if (!setup_APIC_eilvt(offset, 0, APIC_EILVT_MSG_NMI, 0))
1469 		return;
1470 failed:
1471 	pr_warn("perf: IBS APIC setup failed on cpu #%d\n",
1472 		smp_processor_id());
1473 }
1474 
clear_APIC_ibs(void)1475 static void clear_APIC_ibs(void)
1476 {
1477 	int offset;
1478 
1479 	offset = get_ibs_lvt_offset();
1480 	if (offset >= 0)
1481 		setup_APIC_eilvt(offset, 0, APIC_EILVT_MSG_FIX, 1);
1482 }
1483 
x86_pmu_amd_ibs_starting_cpu(unsigned int cpu)1484 static int x86_pmu_amd_ibs_starting_cpu(unsigned int cpu)
1485 {
1486 	setup_APIC_ibs();
1487 	return 0;
1488 }
1489 
1490 #ifdef CONFIG_PM
1491 
perf_ibs_suspend(void)1492 static int perf_ibs_suspend(void)
1493 {
1494 	clear_APIC_ibs();
1495 	return 0;
1496 }
1497 
perf_ibs_resume(void)1498 static void perf_ibs_resume(void)
1499 {
1500 	ibs_eilvt_setup();
1501 	setup_APIC_ibs();
1502 }
1503 
1504 static struct syscore_ops perf_ibs_syscore_ops = {
1505 	.resume		= perf_ibs_resume,
1506 	.suspend	= perf_ibs_suspend,
1507 };
1508 
perf_ibs_pm_init(void)1509 static void perf_ibs_pm_init(void)
1510 {
1511 	register_syscore_ops(&perf_ibs_syscore_ops);
1512 }
1513 
1514 #else
1515 
perf_ibs_pm_init(void)1516 static inline void perf_ibs_pm_init(void) { }
1517 
1518 #endif
1519 
x86_pmu_amd_ibs_dying_cpu(unsigned int cpu)1520 static int x86_pmu_amd_ibs_dying_cpu(unsigned int cpu)
1521 {
1522 	clear_APIC_ibs();
1523 	return 0;
1524 }
1525 
amd_ibs_init(void)1526 static __init int amd_ibs_init(void)
1527 {
1528 	u32 caps;
1529 
1530 	caps = __get_ibs_caps();
1531 	if (!caps)
1532 		return -ENODEV;	/* ibs not supported by the cpu */
1533 
1534 	ibs_eilvt_setup();
1535 
1536 	if (!ibs_eilvt_valid())
1537 		return -EINVAL;
1538 
1539 	perf_ibs_pm_init();
1540 
1541 	ibs_caps = caps;
1542 	/* make ibs_caps visible to other cpus: */
1543 	smp_mb();
1544 	/*
1545 	 * x86_pmu_amd_ibs_starting_cpu will be called from core on
1546 	 * all online cpus.
1547 	 */
1548 	cpuhp_setup_state(CPUHP_AP_PERF_X86_AMD_IBS_STARTING,
1549 			  "perf/x86/amd/ibs:starting",
1550 			  x86_pmu_amd_ibs_starting_cpu,
1551 			  x86_pmu_amd_ibs_dying_cpu);
1552 
1553 	return perf_event_ibs_init();
1554 }
1555 
1556 /* Since we need the pci subsystem to init ibs we can't do this earlier: */
1557 device_initcall(amd_ibs_init);
1558