xref: /openbmc/linux/arch/x86/events/amd/ibs.c (revision 4d75f5c664195b970e1cd2fd25b65b5eff257a0a)
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 	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 		u64 period = 0;
310 
311 		if (perf_ibs == &perf_ibs_op) {
312 			period = (config & IBS_OP_MAX_CNT) << 4;
313 			if (ibs_caps & IBS_CAPS_OPCNTEXT)
314 				period |= config & IBS_OP_MAX_CNT_EXT_MASK;
315 		} else {
316 			period = (config & IBS_FETCH_MAX_CNT) << 4;
317 		}
318 
319 		config &= ~perf_ibs->cnt_mask;
320 		event->attr.sample_period = period;
321 		hwc->sample_period = period;
322 	}
323 
324 	if (!hwc->sample_period)
325 		return -EINVAL;
326 
327 	/*
328 	 * If we modify hwc->sample_period, we also need to update
329 	 * hwc->last_period and hwc->period_left.
330 	 */
331 	hwc->last_period = hwc->sample_period;
332 	local64_set(&hwc->period_left, hwc->sample_period);
333 
334 	hwc->config_base = perf_ibs->msr;
335 	hwc->config = config;
336 
337 	return 0;
338 }
339 
perf_ibs_set_period(struct perf_ibs * perf_ibs,struct hw_perf_event * hwc,u64 * period)340 static int perf_ibs_set_period(struct perf_ibs *perf_ibs,
341 			       struct hw_perf_event *hwc, u64 *period)
342 {
343 	int overflow;
344 
345 	/* ignore lower 4 bits in min count: */
346 	overflow = perf_event_set_period(hwc, 1<<4, perf_ibs->max_period, period);
347 	local64_set(&hwc->prev_count, 0);
348 
349 	return overflow;
350 }
351 
get_ibs_fetch_count(u64 config)352 static u64 get_ibs_fetch_count(u64 config)
353 {
354 	union ibs_fetch_ctl fetch_ctl = (union ibs_fetch_ctl)config;
355 
356 	return fetch_ctl.fetch_cnt << 4;
357 }
358 
get_ibs_op_count(u64 config)359 static u64 get_ibs_op_count(u64 config)
360 {
361 	union ibs_op_ctl op_ctl = (union ibs_op_ctl)config;
362 	u64 count = 0;
363 
364 	/*
365 	 * If the internal 27-bit counter rolled over, the count is MaxCnt
366 	 * and the lower 7 bits of CurCnt are randomized.
367 	 * Otherwise CurCnt has the full 27-bit current counter value.
368 	 */
369 	if (op_ctl.op_val) {
370 		count = op_ctl.opmaxcnt << 4;
371 		if (ibs_caps & IBS_CAPS_OPCNTEXT)
372 			count += op_ctl.opmaxcnt_ext << 20;
373 	} else if (ibs_caps & IBS_CAPS_RDWROPCNT) {
374 		count = op_ctl.opcurcnt;
375 	}
376 
377 	return count;
378 }
379 
380 static void
perf_ibs_event_update(struct perf_ibs * perf_ibs,struct perf_event * event,u64 * config)381 perf_ibs_event_update(struct perf_ibs *perf_ibs, struct perf_event *event,
382 		      u64 *config)
383 {
384 	u64 count = perf_ibs->get_count(*config);
385 
386 	/*
387 	 * Set width to 64 since we do not overflow on max width but
388 	 * instead on max count. In perf_ibs_set_period() we clear
389 	 * prev count manually on overflow.
390 	 */
391 	while (!perf_event_try_update(event, count, 64)) {
392 		rdmsrl(event->hw.config_base, *config);
393 		count = perf_ibs->get_count(*config);
394 	}
395 }
396 
perf_ibs_enable_event(struct perf_ibs * perf_ibs,struct hw_perf_event * hwc,u64 config)397 static inline void perf_ibs_enable_event(struct perf_ibs *perf_ibs,
398 					 struct hw_perf_event *hwc, u64 config)
399 {
400 	u64 tmp = hwc->config | config;
401 
402 	if (perf_ibs->fetch_count_reset_broken)
403 		wrmsrl(hwc->config_base, tmp & ~perf_ibs->enable_mask);
404 
405 	wrmsrl(hwc->config_base, tmp | perf_ibs->enable_mask);
406 }
407 
408 /*
409  * Erratum #420 Instruction-Based Sampling Engine May Generate
410  * Interrupt that Cannot Be Cleared:
411  *
412  * Must clear counter mask first, then clear the enable bit. See
413  * Revision Guide for AMD Family 10h Processors, Publication #41322.
414  */
perf_ibs_disable_event(struct perf_ibs * perf_ibs,struct hw_perf_event * hwc,u64 config)415 static inline void perf_ibs_disable_event(struct perf_ibs *perf_ibs,
416 					  struct hw_perf_event *hwc, u64 config)
417 {
418 	config &= ~perf_ibs->cnt_mask;
419 	if (boot_cpu_data.x86 == 0x10)
420 		wrmsrl(hwc->config_base, config);
421 	config &= ~perf_ibs->enable_mask;
422 	wrmsrl(hwc->config_base, config);
423 }
424 
425 /*
426  * We cannot restore the ibs pmu state, so we always needs to update
427  * the event while stopping it and then reset the state when starting
428  * again. Thus, ignoring PERF_EF_RELOAD and PERF_EF_UPDATE flags in
429  * perf_ibs_start()/perf_ibs_stop() and instead always do it.
430  */
perf_ibs_start(struct perf_event * event,int flags)431 static void perf_ibs_start(struct perf_event *event, int flags)
432 {
433 	struct hw_perf_event *hwc = &event->hw;
434 	struct perf_ibs *perf_ibs = container_of(event->pmu, struct perf_ibs, pmu);
435 	struct cpu_perf_ibs *pcpu = this_cpu_ptr(perf_ibs->pcpu);
436 	u64 period, config = 0;
437 
438 	if (WARN_ON_ONCE(!(hwc->state & PERF_HES_STOPPED)))
439 		return;
440 
441 	WARN_ON_ONCE(!(hwc->state & PERF_HES_UPTODATE));
442 	hwc->state = 0;
443 
444 	perf_ibs_set_period(perf_ibs, hwc, &period);
445 	if (perf_ibs == &perf_ibs_op && (ibs_caps & IBS_CAPS_OPCNTEXT)) {
446 		config |= period & IBS_OP_MAX_CNT_EXT_MASK;
447 		period &= ~IBS_OP_MAX_CNT_EXT_MASK;
448 	}
449 	config |= period >> 4;
450 
451 	/*
452 	 * Set STARTED before enabling the hardware, such that a subsequent NMI
453 	 * must observe it.
454 	 */
455 	set_bit(IBS_STARTED,    pcpu->state);
456 	clear_bit(IBS_STOPPING, pcpu->state);
457 	perf_ibs_enable_event(perf_ibs, hwc, config);
458 
459 	perf_event_update_userpage(event);
460 }
461 
perf_ibs_stop(struct perf_event * event,int flags)462 static void perf_ibs_stop(struct perf_event *event, int flags)
463 {
464 	struct hw_perf_event *hwc = &event->hw;
465 	struct perf_ibs *perf_ibs = container_of(event->pmu, struct perf_ibs, pmu);
466 	struct cpu_perf_ibs *pcpu = this_cpu_ptr(perf_ibs->pcpu);
467 	u64 config;
468 	int stopping;
469 
470 	if (test_and_set_bit(IBS_STOPPING, pcpu->state))
471 		return;
472 
473 	stopping = test_bit(IBS_STARTED, pcpu->state);
474 
475 	if (!stopping && (hwc->state & PERF_HES_UPTODATE))
476 		return;
477 
478 	rdmsrl(hwc->config_base, config);
479 
480 	if (stopping) {
481 		/*
482 		 * Set STOPPED before disabling the hardware, such that it
483 		 * must be visible to NMIs the moment we clear the EN bit,
484 		 * at which point we can generate an !VALID sample which
485 		 * we need to consume.
486 		 */
487 		set_bit(IBS_STOPPED, pcpu->state);
488 		perf_ibs_disable_event(perf_ibs, hwc, config);
489 		/*
490 		 * Clear STARTED after disabling the hardware; if it were
491 		 * cleared before an NMI hitting after the clear but before
492 		 * clearing the EN bit might think it a spurious NMI and not
493 		 * handle it.
494 		 *
495 		 * Clearing it after, however, creates the problem of the NMI
496 		 * handler seeing STARTED but not having a valid sample.
497 		 */
498 		clear_bit(IBS_STARTED, pcpu->state);
499 		WARN_ON_ONCE(hwc->state & PERF_HES_STOPPED);
500 		hwc->state |= PERF_HES_STOPPED;
501 	}
502 
503 	if (hwc->state & PERF_HES_UPTODATE)
504 		return;
505 
506 	/*
507 	 * Clear valid bit to not count rollovers on update, rollovers
508 	 * are only updated in the irq handler.
509 	 */
510 	config &= ~perf_ibs->valid_mask;
511 
512 	perf_ibs_event_update(perf_ibs, event, &config);
513 	hwc->state |= PERF_HES_UPTODATE;
514 }
515 
perf_ibs_add(struct perf_event * event,int flags)516 static int perf_ibs_add(struct perf_event *event, int flags)
517 {
518 	struct perf_ibs *perf_ibs = container_of(event->pmu, struct perf_ibs, pmu);
519 	struct cpu_perf_ibs *pcpu = this_cpu_ptr(perf_ibs->pcpu);
520 
521 	if (test_and_set_bit(IBS_ENABLED, pcpu->state))
522 		return -ENOSPC;
523 
524 	event->hw.state = PERF_HES_UPTODATE | PERF_HES_STOPPED;
525 
526 	pcpu->event = event;
527 
528 	if (flags & PERF_EF_START)
529 		perf_ibs_start(event, PERF_EF_RELOAD);
530 
531 	return 0;
532 }
533 
perf_ibs_del(struct perf_event * event,int flags)534 static void perf_ibs_del(struct perf_event *event, int flags)
535 {
536 	struct perf_ibs *perf_ibs = container_of(event->pmu, struct perf_ibs, pmu);
537 	struct cpu_perf_ibs *pcpu = this_cpu_ptr(perf_ibs->pcpu);
538 
539 	if (!test_and_clear_bit(IBS_ENABLED, pcpu->state))
540 		return;
541 
542 	perf_ibs_stop(event, PERF_EF_UPDATE);
543 
544 	pcpu->event = NULL;
545 
546 	perf_event_update_userpage(event);
547 }
548 
perf_ibs_read(struct perf_event * event)549 static void perf_ibs_read(struct perf_event *event) { }
550 
551 /*
552  * We need to initialize with empty group if all attributes in the
553  * group are dynamic.
554  */
555 static struct attribute *attrs_empty[] = {
556 	NULL,
557 };
558 
559 static struct attribute_group empty_format_group = {
560 	.name = "format",
561 	.attrs = attrs_empty,
562 };
563 
564 static struct attribute_group empty_caps_group = {
565 	.name = "caps",
566 	.attrs = attrs_empty,
567 };
568 
569 static const struct attribute_group *empty_attr_groups[] = {
570 	&empty_format_group,
571 	&empty_caps_group,
572 	NULL,
573 };
574 
575 PMU_FORMAT_ATTR(rand_en,	"config:57");
576 PMU_FORMAT_ATTR(cnt_ctl,	"config:19");
577 PMU_EVENT_ATTR_STRING(l3missonly, fetch_l3missonly, "config:59");
578 PMU_EVENT_ATTR_STRING(l3missonly, op_l3missonly, "config:16");
579 PMU_EVENT_ATTR_STRING(zen4_ibs_extensions, zen4_ibs_extensions, "1");
580 
581 static umode_t
zen4_ibs_extensions_is_visible(struct kobject * kobj,struct attribute * attr,int i)582 zen4_ibs_extensions_is_visible(struct kobject *kobj, struct attribute *attr, int i)
583 {
584 	return ibs_caps & IBS_CAPS_ZEN4 ? attr->mode : 0;
585 }
586 
587 static struct attribute *rand_en_attrs[] = {
588 	&format_attr_rand_en.attr,
589 	NULL,
590 };
591 
592 static struct attribute *fetch_l3missonly_attrs[] = {
593 	&fetch_l3missonly.attr.attr,
594 	NULL,
595 };
596 
597 static struct attribute *zen4_ibs_extensions_attrs[] = {
598 	&zen4_ibs_extensions.attr.attr,
599 	NULL,
600 };
601 
602 static struct attribute_group group_rand_en = {
603 	.name = "format",
604 	.attrs = rand_en_attrs,
605 };
606 
607 static struct attribute_group group_fetch_l3missonly = {
608 	.name = "format",
609 	.attrs = fetch_l3missonly_attrs,
610 	.is_visible = zen4_ibs_extensions_is_visible,
611 };
612 
613 static struct attribute_group group_zen4_ibs_extensions = {
614 	.name = "caps",
615 	.attrs = zen4_ibs_extensions_attrs,
616 	.is_visible = zen4_ibs_extensions_is_visible,
617 };
618 
619 static const struct attribute_group *fetch_attr_groups[] = {
620 	&group_rand_en,
621 	&empty_caps_group,
622 	NULL,
623 };
624 
625 static const struct attribute_group *fetch_attr_update[] = {
626 	&group_fetch_l3missonly,
627 	&group_zen4_ibs_extensions,
628 	NULL,
629 };
630 
631 static umode_t
cnt_ctl_is_visible(struct kobject * kobj,struct attribute * attr,int i)632 cnt_ctl_is_visible(struct kobject *kobj, struct attribute *attr, int i)
633 {
634 	return ibs_caps & IBS_CAPS_OPCNT ? attr->mode : 0;
635 }
636 
637 static struct attribute *cnt_ctl_attrs[] = {
638 	&format_attr_cnt_ctl.attr,
639 	NULL,
640 };
641 
642 static struct attribute *op_l3missonly_attrs[] = {
643 	&op_l3missonly.attr.attr,
644 	NULL,
645 };
646 
647 static struct attribute_group group_cnt_ctl = {
648 	.name = "format",
649 	.attrs = cnt_ctl_attrs,
650 	.is_visible = cnt_ctl_is_visible,
651 };
652 
653 static struct attribute_group group_op_l3missonly = {
654 	.name = "format",
655 	.attrs = op_l3missonly_attrs,
656 	.is_visible = zen4_ibs_extensions_is_visible,
657 };
658 
659 static const struct attribute_group *op_attr_update[] = {
660 	&group_cnt_ctl,
661 	&group_op_l3missonly,
662 	&group_zen4_ibs_extensions,
663 	NULL,
664 };
665 
666 static struct perf_ibs perf_ibs_fetch = {
667 	.pmu = {
668 		.task_ctx_nr	= perf_hw_context,
669 
670 		.event_init	= perf_ibs_init,
671 		.add		= perf_ibs_add,
672 		.del		= perf_ibs_del,
673 		.start		= perf_ibs_start,
674 		.stop		= perf_ibs_stop,
675 		.read		= perf_ibs_read,
676 		.capabilities	= PERF_PMU_CAP_NO_EXCLUDE,
677 	},
678 	.msr			= MSR_AMD64_IBSFETCHCTL,
679 	.config_mask		= IBS_FETCH_CONFIG_MASK,
680 	.cnt_mask		= IBS_FETCH_MAX_CNT,
681 	.enable_mask		= IBS_FETCH_ENABLE,
682 	.valid_mask		= IBS_FETCH_VAL,
683 	.max_period		= IBS_FETCH_MAX_CNT << 4,
684 	.offset_mask		= { MSR_AMD64_IBSFETCH_REG_MASK },
685 	.offset_max		= MSR_AMD64_IBSFETCH_REG_COUNT,
686 
687 	.get_count		= get_ibs_fetch_count,
688 };
689 
690 static struct perf_ibs perf_ibs_op = {
691 	.pmu = {
692 		.task_ctx_nr	= perf_hw_context,
693 
694 		.event_init	= perf_ibs_init,
695 		.add		= perf_ibs_add,
696 		.del		= perf_ibs_del,
697 		.start		= perf_ibs_start,
698 		.stop		= perf_ibs_stop,
699 		.read		= perf_ibs_read,
700 		.capabilities	= PERF_PMU_CAP_NO_EXCLUDE,
701 	},
702 	.msr			= MSR_AMD64_IBSOPCTL,
703 	.config_mask		= IBS_OP_CONFIG_MASK,
704 	.cnt_mask		= IBS_OP_MAX_CNT | IBS_OP_CUR_CNT |
705 				  IBS_OP_CUR_CNT_RAND,
706 	.enable_mask		= IBS_OP_ENABLE,
707 	.valid_mask		= IBS_OP_VAL,
708 	.max_period		= IBS_OP_MAX_CNT << 4,
709 	.offset_mask		= { MSR_AMD64_IBSOP_REG_MASK },
710 	.offset_max		= MSR_AMD64_IBSOP_REG_COUNT,
711 
712 	.get_count		= get_ibs_op_count,
713 };
714 
perf_ibs_get_mem_op(union ibs_op_data3 * op_data3,struct perf_sample_data * data)715 static void perf_ibs_get_mem_op(union ibs_op_data3 *op_data3,
716 				struct perf_sample_data *data)
717 {
718 	union perf_mem_data_src *data_src = &data->data_src;
719 
720 	data_src->mem_op = PERF_MEM_OP_NA;
721 
722 	if (op_data3->ld_op)
723 		data_src->mem_op = PERF_MEM_OP_LOAD;
724 	else if (op_data3->st_op)
725 		data_src->mem_op = PERF_MEM_OP_STORE;
726 }
727 
728 /*
729  * Processors having CPUID_Fn8000001B_EAX[11] aka IBS_CAPS_ZEN4 has
730  * more fine granular DataSrc encodings. Others have coarse.
731  */
perf_ibs_data_src(union ibs_op_data2 * op_data2)732 static u8 perf_ibs_data_src(union ibs_op_data2 *op_data2)
733 {
734 	if (ibs_caps & IBS_CAPS_ZEN4)
735 		return (op_data2->data_src_hi << 3) | op_data2->data_src_lo;
736 
737 	return op_data2->data_src_lo;
738 }
739 
740 #define	L(x)		(PERF_MEM_S(LVL, x) | PERF_MEM_S(LVL, HIT))
741 #define	LN(x)		PERF_MEM_S(LVLNUM, x)
742 #define	REM		PERF_MEM_S(REMOTE, REMOTE)
743 #define	HOPS(x)		PERF_MEM_S(HOPS, x)
744 
745 static u64 g_data_src[8] = {
746 	[IBS_DATA_SRC_LOC_CACHE]	  = L(L3) | L(REM_CCE1) | LN(ANY_CACHE) | HOPS(0),
747 	[IBS_DATA_SRC_DRAM]		  = L(LOC_RAM) | LN(RAM),
748 	[IBS_DATA_SRC_REM_CACHE]	  = L(REM_CCE2) | LN(ANY_CACHE) | REM | HOPS(1),
749 	[IBS_DATA_SRC_IO]		  = L(IO) | LN(IO),
750 };
751 
752 #define RMT_NODE_BITS			(1 << IBS_DATA_SRC_DRAM)
753 #define RMT_NODE_APPLICABLE(x)		(RMT_NODE_BITS & (1 << x))
754 
755 static u64 g_zen4_data_src[32] = {
756 	[IBS_DATA_SRC_EXT_LOC_CACHE]	  = L(L3) | LN(L3),
757 	[IBS_DATA_SRC_EXT_NEAR_CCX_CACHE] = L(REM_CCE1) | LN(ANY_CACHE) | REM | HOPS(0),
758 	[IBS_DATA_SRC_EXT_DRAM]		  = L(LOC_RAM) | LN(RAM),
759 	[IBS_DATA_SRC_EXT_FAR_CCX_CACHE]  = L(REM_CCE2) | LN(ANY_CACHE) | REM | HOPS(1),
760 	[IBS_DATA_SRC_EXT_PMEM]		  = LN(PMEM),
761 	[IBS_DATA_SRC_EXT_IO]		  = L(IO) | LN(IO),
762 	[IBS_DATA_SRC_EXT_EXT_MEM]	  = LN(CXL),
763 };
764 
765 #define ZEN4_RMT_NODE_BITS		((1 << IBS_DATA_SRC_EXT_DRAM) | \
766 					 (1 << IBS_DATA_SRC_EXT_PMEM) | \
767 					 (1 << IBS_DATA_SRC_EXT_EXT_MEM))
768 #define ZEN4_RMT_NODE_APPLICABLE(x)	(ZEN4_RMT_NODE_BITS & (1 << x))
769 
perf_ibs_get_mem_lvl(union ibs_op_data2 * op_data2,union ibs_op_data3 * op_data3,struct perf_sample_data * data)770 static __u64 perf_ibs_get_mem_lvl(union ibs_op_data2 *op_data2,
771 				  union ibs_op_data3 *op_data3,
772 				  struct perf_sample_data *data)
773 {
774 	union perf_mem_data_src *data_src = &data->data_src;
775 	u8 ibs_data_src = perf_ibs_data_src(op_data2);
776 
777 	data_src->mem_lvl = 0;
778 	data_src->mem_lvl_num = 0;
779 
780 	/*
781 	 * DcMiss, L2Miss, DataSrc, DcMissLat etc. are all invalid for Uncached
782 	 * memory accesses. So, check DcUcMemAcc bit early.
783 	 */
784 	if (op_data3->dc_uc_mem_acc && ibs_data_src != IBS_DATA_SRC_EXT_IO)
785 		return L(UNC) | LN(UNC);
786 
787 	/* L1 Hit */
788 	if (op_data3->dc_miss == 0)
789 		return L(L1) | LN(L1);
790 
791 	/* L2 Hit */
792 	if (op_data3->l2_miss == 0) {
793 		/* Erratum #1293 */
794 		if (boot_cpu_data.x86 != 0x19 || boot_cpu_data.x86_model > 0xF ||
795 		    !(op_data3->sw_pf || op_data3->dc_miss_no_mab_alloc))
796 			return L(L2) | LN(L2);
797 	}
798 
799 	/*
800 	 * OP_DATA2 is valid only for load ops. Skip all checks which
801 	 * uses OP_DATA2[DataSrc].
802 	 */
803 	if (data_src->mem_op != PERF_MEM_OP_LOAD)
804 		goto check_mab;
805 
806 	if (ibs_caps & IBS_CAPS_ZEN4) {
807 		u64 val = g_zen4_data_src[ibs_data_src];
808 
809 		if (!val)
810 			goto check_mab;
811 
812 		/* HOPS_1 because IBS doesn't provide remote socket detail */
813 		if (op_data2->rmt_node && ZEN4_RMT_NODE_APPLICABLE(ibs_data_src)) {
814 			if (ibs_data_src == IBS_DATA_SRC_EXT_DRAM)
815 				val = L(REM_RAM1) | LN(RAM) | REM | HOPS(1);
816 			else
817 				val |= REM | HOPS(1);
818 		}
819 
820 		return val;
821 	} else {
822 		u64 val = g_data_src[ibs_data_src];
823 
824 		if (!val)
825 			goto check_mab;
826 
827 		/* HOPS_1 because IBS doesn't provide remote socket detail */
828 		if (op_data2->rmt_node && RMT_NODE_APPLICABLE(ibs_data_src)) {
829 			if (ibs_data_src == IBS_DATA_SRC_DRAM)
830 				val = L(REM_RAM1) | LN(RAM) | REM | HOPS(1);
831 			else
832 				val |= REM | HOPS(1);
833 		}
834 
835 		return val;
836 	}
837 
838 check_mab:
839 	/*
840 	 * MAB (Miss Address Buffer) Hit. MAB keeps track of outstanding
841 	 * DC misses. However, such data may come from any level in mem
842 	 * hierarchy. IBS provides detail about both MAB as well as actual
843 	 * DataSrc simultaneously. Prioritize DataSrc over MAB, i.e. set
844 	 * MAB only when IBS fails to provide DataSrc.
845 	 */
846 	if (op_data3->dc_miss_no_mab_alloc)
847 		return L(LFB) | LN(LFB);
848 
849 	/* Don't set HIT with NA */
850 	return PERF_MEM_S(LVL, NA) | LN(NA);
851 }
852 
perf_ibs_cache_hit_st_valid(void)853 static bool perf_ibs_cache_hit_st_valid(void)
854 {
855 	/* 0: Uninitialized, 1: Valid, -1: Invalid */
856 	static int cache_hit_st_valid;
857 
858 	if (unlikely(!cache_hit_st_valid)) {
859 		if (boot_cpu_data.x86 == 0x19 &&
860 		    (boot_cpu_data.x86_model <= 0xF ||
861 		    (boot_cpu_data.x86_model >= 0x20 &&
862 		     boot_cpu_data.x86_model <= 0x5F))) {
863 			cache_hit_st_valid = -1;
864 		} else {
865 			cache_hit_st_valid = 1;
866 		}
867 	}
868 
869 	return cache_hit_st_valid == 1;
870 }
871 
perf_ibs_get_mem_snoop(union ibs_op_data2 * op_data2,struct perf_sample_data * data)872 static void perf_ibs_get_mem_snoop(union ibs_op_data2 *op_data2,
873 				   struct perf_sample_data *data)
874 {
875 	union perf_mem_data_src *data_src = &data->data_src;
876 	u8 ibs_data_src;
877 
878 	data_src->mem_snoop = PERF_MEM_SNOOP_NA;
879 
880 	if (!perf_ibs_cache_hit_st_valid() ||
881 	    data_src->mem_op != PERF_MEM_OP_LOAD ||
882 	    data_src->mem_lvl & PERF_MEM_LVL_L1 ||
883 	    data_src->mem_lvl & PERF_MEM_LVL_L2 ||
884 	    op_data2->cache_hit_st)
885 		return;
886 
887 	ibs_data_src = perf_ibs_data_src(op_data2);
888 
889 	if (ibs_caps & IBS_CAPS_ZEN4) {
890 		if (ibs_data_src == IBS_DATA_SRC_EXT_LOC_CACHE ||
891 		    ibs_data_src == IBS_DATA_SRC_EXT_NEAR_CCX_CACHE ||
892 		    ibs_data_src == IBS_DATA_SRC_EXT_FAR_CCX_CACHE)
893 			data_src->mem_snoop = PERF_MEM_SNOOP_HITM;
894 	} else if (ibs_data_src == IBS_DATA_SRC_LOC_CACHE) {
895 		data_src->mem_snoop = PERF_MEM_SNOOP_HITM;
896 	}
897 }
898 
perf_ibs_get_tlb_lvl(union ibs_op_data3 * op_data3,struct perf_sample_data * data)899 static void perf_ibs_get_tlb_lvl(union ibs_op_data3 *op_data3,
900 				 struct perf_sample_data *data)
901 {
902 	union perf_mem_data_src *data_src = &data->data_src;
903 
904 	data_src->mem_dtlb = PERF_MEM_TLB_NA;
905 
906 	if (!op_data3->dc_lin_addr_valid)
907 		return;
908 
909 	if (!op_data3->dc_l1tlb_miss) {
910 		data_src->mem_dtlb = PERF_MEM_TLB_L1 | PERF_MEM_TLB_HIT;
911 		return;
912 	}
913 
914 	if (!op_data3->dc_l2tlb_miss) {
915 		data_src->mem_dtlb = PERF_MEM_TLB_L2 | PERF_MEM_TLB_HIT;
916 		return;
917 	}
918 
919 	data_src->mem_dtlb = PERF_MEM_TLB_L2 | PERF_MEM_TLB_MISS;
920 }
921 
perf_ibs_get_mem_lock(union ibs_op_data3 * op_data3,struct perf_sample_data * data)922 static void perf_ibs_get_mem_lock(union ibs_op_data3 *op_data3,
923 				  struct perf_sample_data *data)
924 {
925 	union perf_mem_data_src *data_src = &data->data_src;
926 
927 	data_src->mem_lock = PERF_MEM_LOCK_NA;
928 
929 	if (op_data3->dc_locked_op)
930 		data_src->mem_lock = PERF_MEM_LOCK_LOCKED;
931 }
932 
933 #define ibs_op_msr_idx(msr)	(msr - MSR_AMD64_IBSOPCTL)
934 
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)935 static void perf_ibs_get_data_src(struct perf_ibs_data *ibs_data,
936 				  struct perf_sample_data *data,
937 				  union ibs_op_data2 *op_data2,
938 				  union ibs_op_data3 *op_data3)
939 {
940 	union perf_mem_data_src *data_src = &data->data_src;
941 
942 	data_src->val |= perf_ibs_get_mem_lvl(op_data2, op_data3, data);
943 	perf_ibs_get_mem_snoop(op_data2, data);
944 	perf_ibs_get_tlb_lvl(op_data3, data);
945 	perf_ibs_get_mem_lock(op_data3, data);
946 }
947 
perf_ibs_get_op_data2(struct perf_ibs_data * ibs_data,union ibs_op_data3 * op_data3)948 static __u64 perf_ibs_get_op_data2(struct perf_ibs_data *ibs_data,
949 				   union ibs_op_data3 *op_data3)
950 {
951 	__u64 val = ibs_data->regs[ibs_op_msr_idx(MSR_AMD64_IBSOPDATA2)];
952 
953 	/* Erratum #1293 */
954 	if (boot_cpu_data.x86 == 0x19 && boot_cpu_data.x86_model <= 0xF &&
955 	    (op_data3->sw_pf || op_data3->dc_miss_no_mab_alloc)) {
956 		/*
957 		 * OP_DATA2 has only two fields on Zen3: DataSrc and RmtNode.
958 		 * DataSrc=0 is 'No valid status' and RmtNode is invalid when
959 		 * DataSrc=0.
960 		 */
961 		val = 0;
962 	}
963 	return val;
964 }
965 
perf_ibs_parse_ld_st_data(__u64 sample_type,struct perf_ibs_data * ibs_data,struct perf_sample_data * data)966 static void perf_ibs_parse_ld_st_data(__u64 sample_type,
967 				      struct perf_ibs_data *ibs_data,
968 				      struct perf_sample_data *data)
969 {
970 	union ibs_op_data3 op_data3;
971 	union ibs_op_data2 op_data2;
972 	union ibs_op_data op_data;
973 
974 	data->data_src.val = PERF_MEM_NA;
975 	op_data3.val = ibs_data->regs[ibs_op_msr_idx(MSR_AMD64_IBSOPDATA3)];
976 
977 	perf_ibs_get_mem_op(&op_data3, data);
978 	if (data->data_src.mem_op != PERF_MEM_OP_LOAD &&
979 	    data->data_src.mem_op != PERF_MEM_OP_STORE)
980 		return;
981 
982 	op_data2.val = perf_ibs_get_op_data2(ibs_data, &op_data3);
983 
984 	if (sample_type & PERF_SAMPLE_DATA_SRC) {
985 		perf_ibs_get_data_src(ibs_data, data, &op_data2, &op_data3);
986 		data->sample_flags |= PERF_SAMPLE_DATA_SRC;
987 	}
988 
989 	if (sample_type & PERF_SAMPLE_WEIGHT_TYPE && op_data3.dc_miss &&
990 	    data->data_src.mem_op == PERF_MEM_OP_LOAD) {
991 		op_data.val = ibs_data->regs[ibs_op_msr_idx(MSR_AMD64_IBSOPDATA)];
992 
993 		if (sample_type & PERF_SAMPLE_WEIGHT_STRUCT) {
994 			data->weight.var1_dw = op_data3.dc_miss_lat;
995 			data->weight.var2_w = op_data.tag_to_ret_ctr;
996 		} else if (sample_type & PERF_SAMPLE_WEIGHT) {
997 			data->weight.full = op_data3.dc_miss_lat;
998 		}
999 		data->sample_flags |= PERF_SAMPLE_WEIGHT_TYPE;
1000 	}
1001 
1002 	if (sample_type & PERF_SAMPLE_ADDR && op_data3.dc_lin_addr_valid) {
1003 		data->addr = ibs_data->regs[ibs_op_msr_idx(MSR_AMD64_IBSDCLINAD)];
1004 		data->sample_flags |= PERF_SAMPLE_ADDR;
1005 	}
1006 
1007 	if (sample_type & PERF_SAMPLE_PHYS_ADDR && op_data3.dc_phy_addr_valid) {
1008 		data->phys_addr = ibs_data->regs[ibs_op_msr_idx(MSR_AMD64_IBSDCPHYSAD)];
1009 		data->sample_flags |= PERF_SAMPLE_PHYS_ADDR;
1010 	}
1011 }
1012 
perf_ibs_get_offset_max(struct perf_ibs * perf_ibs,u64 sample_type,int check_rip)1013 static int perf_ibs_get_offset_max(struct perf_ibs *perf_ibs, u64 sample_type,
1014 				   int check_rip)
1015 {
1016 	if (sample_type & PERF_SAMPLE_RAW ||
1017 	    (perf_ibs == &perf_ibs_op &&
1018 	     (sample_type & PERF_SAMPLE_DATA_SRC ||
1019 	      sample_type & PERF_SAMPLE_WEIGHT_TYPE ||
1020 	      sample_type & PERF_SAMPLE_ADDR ||
1021 	      sample_type & PERF_SAMPLE_PHYS_ADDR)))
1022 		return perf_ibs->offset_max;
1023 	else if (check_rip)
1024 		return 3;
1025 	return 1;
1026 }
1027 
perf_ibs_handle_irq(struct perf_ibs * perf_ibs,struct pt_regs * iregs)1028 static int perf_ibs_handle_irq(struct perf_ibs *perf_ibs, struct pt_regs *iregs)
1029 {
1030 	struct cpu_perf_ibs *pcpu = this_cpu_ptr(perf_ibs->pcpu);
1031 	struct perf_event *event = pcpu->event;
1032 	struct hw_perf_event *hwc;
1033 	struct perf_sample_data data;
1034 	struct perf_raw_record raw;
1035 	struct pt_regs regs;
1036 	struct perf_ibs_data ibs_data;
1037 	int offset, size, check_rip, offset_max, throttle = 0;
1038 	unsigned int msr;
1039 	u64 *buf, *config, period, new_config = 0;
1040 
1041 	if (!test_bit(IBS_STARTED, pcpu->state)) {
1042 fail:
1043 		/*
1044 		 * Catch spurious interrupts after stopping IBS: After
1045 		 * disabling IBS there could be still incoming NMIs
1046 		 * with samples that even have the valid bit cleared.
1047 		 * Mark all this NMIs as handled.
1048 		 */
1049 		if (test_and_clear_bit(IBS_STOPPED, pcpu->state))
1050 			return 1;
1051 
1052 		return 0;
1053 	}
1054 
1055 	if (WARN_ON_ONCE(!event))
1056 		goto fail;
1057 
1058 	hwc = &event->hw;
1059 	msr = hwc->config_base;
1060 	buf = ibs_data.regs;
1061 	rdmsrl(msr, *buf);
1062 	if (!(*buf++ & perf_ibs->valid_mask))
1063 		goto fail;
1064 
1065 	config = &ibs_data.regs[0];
1066 	perf_ibs_event_update(perf_ibs, event, config);
1067 	perf_sample_data_init(&data, 0, hwc->last_period);
1068 	if (!perf_ibs_set_period(perf_ibs, hwc, &period))
1069 		goto out;	/* no sw counter overflow */
1070 
1071 	ibs_data.caps = ibs_caps;
1072 	size = 1;
1073 	offset = 1;
1074 	check_rip = (perf_ibs == &perf_ibs_op && (ibs_caps & IBS_CAPS_RIPINVALIDCHK));
1075 
1076 	offset_max = perf_ibs_get_offset_max(perf_ibs, event->attr.sample_type, check_rip);
1077 
1078 	do {
1079 		rdmsrl(msr + offset, *buf++);
1080 		size++;
1081 		offset = find_next_bit(perf_ibs->offset_mask,
1082 				       perf_ibs->offset_max,
1083 				       offset + 1);
1084 	} while (offset < offset_max);
1085 	/*
1086 	 * Read IbsBrTarget, IbsOpData4, and IbsExtdCtl separately
1087 	 * depending on their availability.
1088 	 * Can't add to offset_max as they are staggered
1089 	 */
1090 	if (event->attr.sample_type & PERF_SAMPLE_RAW) {
1091 		if (perf_ibs == &perf_ibs_op) {
1092 			if (ibs_caps & IBS_CAPS_BRNTRGT) {
1093 				rdmsrl(MSR_AMD64_IBSBRTARGET, *buf++);
1094 				size++;
1095 			}
1096 			if (ibs_caps & IBS_CAPS_OPDATA4) {
1097 				rdmsrl(MSR_AMD64_IBSOPDATA4, *buf++);
1098 				size++;
1099 			}
1100 		}
1101 		if (perf_ibs == &perf_ibs_fetch && (ibs_caps & IBS_CAPS_FETCHCTLEXTD)) {
1102 			rdmsrl(MSR_AMD64_ICIBSEXTDCTL, *buf++);
1103 			size++;
1104 		}
1105 	}
1106 	ibs_data.size = sizeof(u64) * size;
1107 
1108 	regs = *iregs;
1109 	if (check_rip && (ibs_data.regs[2] & IBS_RIP_INVALID)) {
1110 		regs.flags &= ~PERF_EFLAGS_EXACT;
1111 	} else {
1112 		/* Workaround for erratum #1197 */
1113 		if (perf_ibs->fetch_ignore_if_zero_rip && !(ibs_data.regs[1]))
1114 			goto out;
1115 
1116 		set_linear_ip(&regs, ibs_data.regs[1]);
1117 		regs.flags |= PERF_EFLAGS_EXACT;
1118 	}
1119 
1120 	if (event->attr.sample_type & PERF_SAMPLE_RAW) {
1121 		raw = (struct perf_raw_record){
1122 			.frag = {
1123 				.size = sizeof(u32) + ibs_data.size,
1124 				.data = ibs_data.data,
1125 			},
1126 		};
1127 		perf_sample_save_raw_data(&data, event, &raw);
1128 	}
1129 
1130 	if (perf_ibs == &perf_ibs_op)
1131 		perf_ibs_parse_ld_st_data(event->attr.sample_type, &ibs_data, &data);
1132 
1133 	/*
1134 	 * rip recorded by IbsOpRip will not be consistent with rsp and rbp
1135 	 * recorded as part of interrupt regs. Thus we need to use rip from
1136 	 * interrupt regs while unwinding call stack.
1137 	 */
1138 	if (event->attr.sample_type & PERF_SAMPLE_CALLCHAIN)
1139 		perf_sample_save_callchain(&data, event, iregs);
1140 
1141 	throttle = perf_event_overflow(event, &data, &regs);
1142 out:
1143 	if (throttle) {
1144 		perf_ibs_stop(event, 0);
1145 	} else {
1146 		if (perf_ibs == &perf_ibs_op) {
1147 			if (ibs_caps & IBS_CAPS_OPCNTEXT) {
1148 				new_config = period & IBS_OP_MAX_CNT_EXT_MASK;
1149 				period &= ~IBS_OP_MAX_CNT_EXT_MASK;
1150 			}
1151 			if ((ibs_caps & IBS_CAPS_RDWROPCNT) && (*config & IBS_OP_CNT_CTL))
1152 				new_config |= *config & IBS_OP_CUR_CNT_RAND;
1153 		}
1154 		new_config |= period >> 4;
1155 
1156 		perf_ibs_enable_event(perf_ibs, hwc, new_config);
1157 	}
1158 
1159 	perf_event_update_userpage(event);
1160 
1161 	return 1;
1162 }
1163 
1164 static int
perf_ibs_nmi_handler(unsigned int cmd,struct pt_regs * regs)1165 perf_ibs_nmi_handler(unsigned int cmd, struct pt_regs *regs)
1166 {
1167 	u64 stamp = sched_clock();
1168 	int handled = 0;
1169 
1170 	handled += perf_ibs_handle_irq(&perf_ibs_fetch, regs);
1171 	handled += perf_ibs_handle_irq(&perf_ibs_op, regs);
1172 
1173 	if (handled)
1174 		inc_irq_stat(apic_perf_irqs);
1175 
1176 	perf_sample_event_took(sched_clock() - stamp);
1177 
1178 	return handled;
1179 }
1180 NOKPROBE_SYMBOL(perf_ibs_nmi_handler);
1181 
perf_ibs_pmu_init(struct perf_ibs * perf_ibs,char * name)1182 static __init int perf_ibs_pmu_init(struct perf_ibs *perf_ibs, char *name)
1183 {
1184 	struct cpu_perf_ibs __percpu *pcpu;
1185 	int ret;
1186 
1187 	pcpu = alloc_percpu(struct cpu_perf_ibs);
1188 	if (!pcpu)
1189 		return -ENOMEM;
1190 
1191 	perf_ibs->pcpu = pcpu;
1192 
1193 	ret = perf_pmu_register(&perf_ibs->pmu, name, -1);
1194 	if (ret) {
1195 		perf_ibs->pcpu = NULL;
1196 		free_percpu(pcpu);
1197 	}
1198 
1199 	return ret;
1200 }
1201 
perf_ibs_fetch_init(void)1202 static __init int perf_ibs_fetch_init(void)
1203 {
1204 	/*
1205 	 * Some chips fail to reset the fetch count when it is written; instead
1206 	 * they need a 0-1 transition of IbsFetchEn.
1207 	 */
1208 	if (boot_cpu_data.x86 >= 0x16 && boot_cpu_data.x86 <= 0x18)
1209 		perf_ibs_fetch.fetch_count_reset_broken = 1;
1210 
1211 	if (boot_cpu_data.x86 == 0x19 && boot_cpu_data.x86_model < 0x10)
1212 		perf_ibs_fetch.fetch_ignore_if_zero_rip = 1;
1213 
1214 	if (ibs_caps & IBS_CAPS_ZEN4)
1215 		perf_ibs_fetch.config_mask |= IBS_FETCH_L3MISSONLY;
1216 
1217 	perf_ibs_fetch.pmu.attr_groups = fetch_attr_groups;
1218 	perf_ibs_fetch.pmu.attr_update = fetch_attr_update;
1219 
1220 	return perf_ibs_pmu_init(&perf_ibs_fetch, "ibs_fetch");
1221 }
1222 
perf_ibs_op_init(void)1223 static __init int perf_ibs_op_init(void)
1224 {
1225 	if (ibs_caps & IBS_CAPS_OPCNT)
1226 		perf_ibs_op.config_mask |= IBS_OP_CNT_CTL;
1227 
1228 	if (ibs_caps & IBS_CAPS_OPCNTEXT) {
1229 		perf_ibs_op.max_period  |= IBS_OP_MAX_CNT_EXT_MASK;
1230 		perf_ibs_op.config_mask	|= IBS_OP_MAX_CNT_EXT_MASK;
1231 		perf_ibs_op.cnt_mask    |= (IBS_OP_MAX_CNT_EXT_MASK |
1232 					    IBS_OP_CUR_CNT_EXT_MASK);
1233 	}
1234 
1235 	if (ibs_caps & IBS_CAPS_ZEN4)
1236 		perf_ibs_op.config_mask |= IBS_OP_L3MISSONLY;
1237 
1238 	perf_ibs_op.pmu.attr_groups = empty_attr_groups;
1239 	perf_ibs_op.pmu.attr_update = op_attr_update;
1240 
1241 	return perf_ibs_pmu_init(&perf_ibs_op, "ibs_op");
1242 }
1243 
perf_event_ibs_init(void)1244 static __init int perf_event_ibs_init(void)
1245 {
1246 	int ret;
1247 
1248 	ret = perf_ibs_fetch_init();
1249 	if (ret)
1250 		return ret;
1251 
1252 	ret = perf_ibs_op_init();
1253 	if (ret)
1254 		goto err_op;
1255 
1256 	ret = register_nmi_handler(NMI_LOCAL, perf_ibs_nmi_handler, 0, "perf_ibs");
1257 	if (ret)
1258 		goto err_nmi;
1259 
1260 	pr_info("perf: AMD IBS detected (0x%08x)\n", ibs_caps);
1261 	return 0;
1262 
1263 err_nmi:
1264 	perf_pmu_unregister(&perf_ibs_op.pmu);
1265 	free_percpu(perf_ibs_op.pcpu);
1266 	perf_ibs_op.pcpu = NULL;
1267 err_op:
1268 	perf_pmu_unregister(&perf_ibs_fetch.pmu);
1269 	free_percpu(perf_ibs_fetch.pcpu);
1270 	perf_ibs_fetch.pcpu = NULL;
1271 
1272 	return ret;
1273 }
1274 
1275 #else /* defined(CONFIG_PERF_EVENTS) && defined(CONFIG_CPU_SUP_AMD) */
1276 
perf_event_ibs_init(void)1277 static __init int perf_event_ibs_init(void)
1278 {
1279 	return 0;
1280 }
1281 
1282 #endif
1283 
1284 /* IBS - apic initialization, for perf and oprofile */
1285 
__get_ibs_caps(void)1286 static __init u32 __get_ibs_caps(void)
1287 {
1288 	u32 caps;
1289 	unsigned int max_level;
1290 
1291 	if (!boot_cpu_has(X86_FEATURE_IBS))
1292 		return 0;
1293 
1294 	/* check IBS cpuid feature flags */
1295 	max_level = cpuid_eax(0x80000000);
1296 	if (max_level < IBS_CPUID_FEATURES)
1297 		return IBS_CAPS_DEFAULT;
1298 
1299 	caps = cpuid_eax(IBS_CPUID_FEATURES);
1300 	if (!(caps & IBS_CAPS_AVAIL))
1301 		/* cpuid flags not valid */
1302 		return IBS_CAPS_DEFAULT;
1303 
1304 	return caps;
1305 }
1306 
get_ibs_caps(void)1307 u32 get_ibs_caps(void)
1308 {
1309 	return ibs_caps;
1310 }
1311 
1312 EXPORT_SYMBOL(get_ibs_caps);
1313 
get_eilvt(int offset)1314 static inline int get_eilvt(int offset)
1315 {
1316 	return !setup_APIC_eilvt(offset, 0, APIC_EILVT_MSG_NMI, 1);
1317 }
1318 
put_eilvt(int offset)1319 static inline int put_eilvt(int offset)
1320 {
1321 	return !setup_APIC_eilvt(offset, 0, 0, 1);
1322 }
1323 
1324 /*
1325  * Check and reserve APIC extended interrupt LVT offset for IBS if available.
1326  */
ibs_eilvt_valid(void)1327 static inline int ibs_eilvt_valid(void)
1328 {
1329 	int offset;
1330 	u64 val;
1331 	int valid = 0;
1332 
1333 	preempt_disable();
1334 
1335 	rdmsrl(MSR_AMD64_IBSCTL, val);
1336 	offset = val & IBSCTL_LVT_OFFSET_MASK;
1337 
1338 	if (!(val & IBSCTL_LVT_OFFSET_VALID)) {
1339 		pr_err(FW_BUG "cpu %d, invalid IBS interrupt offset %d (MSR%08X=0x%016llx)\n",
1340 		       smp_processor_id(), offset, MSR_AMD64_IBSCTL, val);
1341 		goto out;
1342 	}
1343 
1344 	if (!get_eilvt(offset)) {
1345 		pr_err(FW_BUG "cpu %d, IBS interrupt offset %d not available (MSR%08X=0x%016llx)\n",
1346 		       smp_processor_id(), offset, MSR_AMD64_IBSCTL, val);
1347 		goto out;
1348 	}
1349 
1350 	valid = 1;
1351 out:
1352 	preempt_enable();
1353 
1354 	return valid;
1355 }
1356 
setup_ibs_ctl(int ibs_eilvt_off)1357 static int setup_ibs_ctl(int ibs_eilvt_off)
1358 {
1359 	struct pci_dev *cpu_cfg;
1360 	int nodes;
1361 	u32 value = 0;
1362 
1363 	nodes = 0;
1364 	cpu_cfg = NULL;
1365 	do {
1366 		cpu_cfg = pci_get_device(PCI_VENDOR_ID_AMD,
1367 					 PCI_DEVICE_ID_AMD_10H_NB_MISC,
1368 					 cpu_cfg);
1369 		if (!cpu_cfg)
1370 			break;
1371 		++nodes;
1372 		pci_write_config_dword(cpu_cfg, IBSCTL, ibs_eilvt_off
1373 				       | IBSCTL_LVT_OFFSET_VALID);
1374 		pci_read_config_dword(cpu_cfg, IBSCTL, &value);
1375 		if (value != (ibs_eilvt_off | IBSCTL_LVT_OFFSET_VALID)) {
1376 			pci_dev_put(cpu_cfg);
1377 			pr_debug("Failed to setup IBS LVT offset, IBSCTL = 0x%08x\n",
1378 				 value);
1379 			return -EINVAL;
1380 		}
1381 	} while (1);
1382 
1383 	if (!nodes) {
1384 		pr_debug("No CPU node configured for IBS\n");
1385 		return -ENODEV;
1386 	}
1387 
1388 	return 0;
1389 }
1390 
1391 /*
1392  * This runs only on the current cpu. We try to find an LVT offset and
1393  * setup the local APIC. For this we must disable preemption. On
1394  * success we initialize all nodes with this offset. This updates then
1395  * the offset in the IBS_CTL per-node msr. The per-core APIC setup of
1396  * the IBS interrupt vector is handled by perf_ibs_cpu_notifier that
1397  * is using the new offset.
1398  */
force_ibs_eilvt_setup(void)1399 static void force_ibs_eilvt_setup(void)
1400 {
1401 	int offset;
1402 	int ret;
1403 
1404 	preempt_disable();
1405 	/* find the next free available EILVT entry, skip offset 0 */
1406 	for (offset = 1; offset < APIC_EILVT_NR_MAX; offset++) {
1407 		if (get_eilvt(offset))
1408 			break;
1409 	}
1410 	preempt_enable();
1411 
1412 	if (offset == APIC_EILVT_NR_MAX) {
1413 		pr_debug("No EILVT entry available\n");
1414 		return;
1415 	}
1416 
1417 	ret = setup_ibs_ctl(offset);
1418 	if (ret)
1419 		goto out;
1420 
1421 	if (!ibs_eilvt_valid())
1422 		goto out;
1423 
1424 	pr_info("LVT offset %d assigned\n", offset);
1425 
1426 	return;
1427 out:
1428 	preempt_disable();
1429 	put_eilvt(offset);
1430 	preempt_enable();
1431 	return;
1432 }
1433 
ibs_eilvt_setup(void)1434 static void ibs_eilvt_setup(void)
1435 {
1436 	/*
1437 	 * Force LVT offset assignment for family 10h: The offsets are
1438 	 * not assigned by the BIOS for this family, so the OS is
1439 	 * responsible for doing it. If the OS assignment fails, fall
1440 	 * back to BIOS settings and try to setup this.
1441 	 */
1442 	if (boot_cpu_data.x86 == 0x10)
1443 		force_ibs_eilvt_setup();
1444 }
1445 
get_ibs_lvt_offset(void)1446 static inline int get_ibs_lvt_offset(void)
1447 {
1448 	u64 val;
1449 
1450 	rdmsrl(MSR_AMD64_IBSCTL, val);
1451 	if (!(val & IBSCTL_LVT_OFFSET_VALID))
1452 		return -EINVAL;
1453 
1454 	return val & IBSCTL_LVT_OFFSET_MASK;
1455 }
1456 
setup_APIC_ibs(void)1457 static void setup_APIC_ibs(void)
1458 {
1459 	int offset;
1460 
1461 	offset = get_ibs_lvt_offset();
1462 	if (offset < 0)
1463 		goto failed;
1464 
1465 	if (!setup_APIC_eilvt(offset, 0, APIC_EILVT_MSG_NMI, 0))
1466 		return;
1467 failed:
1468 	pr_warn("perf: IBS APIC setup failed on cpu #%d\n",
1469 		smp_processor_id());
1470 }
1471 
clear_APIC_ibs(void)1472 static void clear_APIC_ibs(void)
1473 {
1474 	int offset;
1475 
1476 	offset = get_ibs_lvt_offset();
1477 	if (offset >= 0)
1478 		setup_APIC_eilvt(offset, 0, APIC_EILVT_MSG_FIX, 1);
1479 }
1480 
x86_pmu_amd_ibs_starting_cpu(unsigned int cpu)1481 static int x86_pmu_amd_ibs_starting_cpu(unsigned int cpu)
1482 {
1483 	setup_APIC_ibs();
1484 	return 0;
1485 }
1486 
1487 #ifdef CONFIG_PM
1488 
perf_ibs_suspend(void)1489 static int perf_ibs_suspend(void)
1490 {
1491 	clear_APIC_ibs();
1492 	return 0;
1493 }
1494 
perf_ibs_resume(void)1495 static void perf_ibs_resume(void)
1496 {
1497 	ibs_eilvt_setup();
1498 	setup_APIC_ibs();
1499 }
1500 
1501 static struct syscore_ops perf_ibs_syscore_ops = {
1502 	.resume		= perf_ibs_resume,
1503 	.suspend	= perf_ibs_suspend,
1504 };
1505 
perf_ibs_pm_init(void)1506 static void perf_ibs_pm_init(void)
1507 {
1508 	register_syscore_ops(&perf_ibs_syscore_ops);
1509 }
1510 
1511 #else
1512 
perf_ibs_pm_init(void)1513 static inline void perf_ibs_pm_init(void) { }
1514 
1515 #endif
1516 
x86_pmu_amd_ibs_dying_cpu(unsigned int cpu)1517 static int x86_pmu_amd_ibs_dying_cpu(unsigned int cpu)
1518 {
1519 	clear_APIC_ibs();
1520 	return 0;
1521 }
1522 
amd_ibs_init(void)1523 static __init int amd_ibs_init(void)
1524 {
1525 	u32 caps;
1526 
1527 	caps = __get_ibs_caps();
1528 	if (!caps)
1529 		return -ENODEV;	/* ibs not supported by the cpu */
1530 
1531 	ibs_eilvt_setup();
1532 
1533 	if (!ibs_eilvt_valid())
1534 		return -EINVAL;
1535 
1536 	perf_ibs_pm_init();
1537 
1538 	ibs_caps = caps;
1539 	/* make ibs_caps visible to other cpus: */
1540 	smp_mb();
1541 	/*
1542 	 * x86_pmu_amd_ibs_starting_cpu will be called from core on
1543 	 * all online cpus.
1544 	 */
1545 	cpuhp_setup_state(CPUHP_AP_PERF_X86_AMD_IBS_STARTING,
1546 			  "perf/x86/amd/ibs:starting",
1547 			  x86_pmu_amd_ibs_starting_cpu,
1548 			  x86_pmu_amd_ibs_dying_cpu);
1549 
1550 	return perf_event_ibs_init();
1551 }
1552 
1553 /* Since we need the pci subsystem to init ibs we can't do this earlier: */
1554 device_initcall(amd_ibs_init);
1555