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1/*
2 * SPDX-License-Identifier: MIT
3 *
4 * Copyright © 2017-2018 Intel Corporation
5 */
6
7#include <linux/pm_runtime.h>
8
9#include "gt/intel_engine.h"
10#include "gt/intel_engine_pm.h"
11#include "gt/intel_engine_user.h"
12#include "gt/intel_gt_pm.h"
13#include "gt/intel_rc6.h"
14#include "gt/intel_rps.h"
15
16#include "i915_drv.h"
17#include "i915_pmu.h"
18#include "intel_pm.h"
19
20/* Frequency for the sampling timer for events which need it. */
21#define FREQUENCY 200
22#define PERIOD max_t(u64, 10000, NSEC_PER_SEC / FREQUENCY)
23
24#define ENGINE_SAMPLE_MASK \
25 (BIT(I915_SAMPLE_BUSY) | \
26 BIT(I915_SAMPLE_WAIT) | \
27 BIT(I915_SAMPLE_SEMA))
28
29static cpumask_t i915_pmu_cpumask;
30static unsigned int i915_pmu_target_cpu = -1;
31
32static u8 engine_config_sample(u64 config)
33{
34 return config & I915_PMU_SAMPLE_MASK;
35}
36
37static u8 engine_event_sample(struct perf_event *event)
38{
39 return engine_config_sample(event->attr.config);
40}
41
42static u8 engine_event_class(struct perf_event *event)
43{
44 return (event->attr.config >> I915_PMU_CLASS_SHIFT) & 0xff;
45}
46
47static u8 engine_event_instance(struct perf_event *event)
48{
49 return (event->attr.config >> I915_PMU_SAMPLE_BITS) & 0xff;
50}
51
52static bool is_engine_config(u64 config)
53{
54 return config < __I915_PMU_OTHER(0);
55}
56
57static unsigned int other_bit(const u64 config)
58{
59 unsigned int val;
60
61 switch (config) {
62 case I915_PMU_ACTUAL_FREQUENCY:
63 val = __I915_PMU_ACTUAL_FREQUENCY_ENABLED;
64 break;
65 case I915_PMU_REQUESTED_FREQUENCY:
66 val = __I915_PMU_REQUESTED_FREQUENCY_ENABLED;
67 break;
68 case I915_PMU_RC6_RESIDENCY:
69 val = __I915_PMU_RC6_RESIDENCY_ENABLED;
70 break;
71 default:
72 /*
73 * Events that do not require sampling, or tracking state
74 * transitions between enabled and disabled can be ignored.
75 */
76 return -1;
77 }
78
79 return I915_ENGINE_SAMPLE_COUNT + val;
80}
81
82static unsigned int config_bit(const u64 config)
83{
84 if (is_engine_config(config))
85 return engine_config_sample(config);
86 else
87 return other_bit(config);
88}
89
90static u64 config_mask(u64 config)
91{
92 return BIT_ULL(config_bit(config));
93}
94
95static bool is_engine_event(struct perf_event *event)
96{
97 return is_engine_config(event->attr.config);
98}
99
100static unsigned int event_bit(struct perf_event *event)
101{
102 return config_bit(event->attr.config);
103}
104
105static bool pmu_needs_timer(struct i915_pmu *pmu, bool gpu_active)
106{
107 struct drm_i915_private *i915 = container_of(pmu, typeof(*i915), pmu);
108 u32 enable;
109
110 /*
111 * Only some counters need the sampling timer.
112 *
113 * We start with a bitmask of all currently enabled events.
114 */
115 enable = pmu->enable;
116
117 /*
118 * Mask out all the ones which do not need the timer, or in
119 * other words keep all the ones that could need the timer.
120 */
121 enable &= config_mask(I915_PMU_ACTUAL_FREQUENCY) |
122 config_mask(I915_PMU_REQUESTED_FREQUENCY) |
123 ENGINE_SAMPLE_MASK;
124
125 /*
126 * When the GPU is idle per-engine counters do not need to be
127 * running so clear those bits out.
128 */
129 if (!gpu_active)
130 enable &= ~ENGINE_SAMPLE_MASK;
131 /*
132 * Also there is software busyness tracking available we do not
133 * need the timer for I915_SAMPLE_BUSY counter.
134 */
135 else if (i915->caps.scheduler & I915_SCHEDULER_CAP_ENGINE_BUSY_STATS)
136 enable &= ~BIT(I915_SAMPLE_BUSY);
137
138 /*
139 * If some bits remain it means we need the sampling timer running.
140 */
141 return enable;
142}
143
144static u64 __get_rc6(struct intel_gt *gt)
145{
146 struct drm_i915_private *i915 = gt->i915;
147 u64 val;
148
149 val = intel_rc6_residency_ns(>->rc6,
150 IS_VALLEYVIEW(i915) ?
151 VLV_GT_RENDER_RC6 :
152 GEN6_GT_GFX_RC6);
153
154 if (HAS_RC6p(i915))
155 val += intel_rc6_residency_ns(>->rc6, GEN6_GT_GFX_RC6p);
156
157 if (HAS_RC6pp(i915))
158 val += intel_rc6_residency_ns(>->rc6, GEN6_GT_GFX_RC6pp);
159
160 return val;
161}
162
163static inline s64 ktime_since_raw(const ktime_t kt)
164{
165 return ktime_to_ns(ktime_sub(ktime_get_raw(), kt));
166}
167
168static u64 get_rc6(struct intel_gt *gt)
169{
170 struct drm_i915_private *i915 = gt->i915;
171 struct i915_pmu *pmu = &i915->pmu;
172 unsigned long flags;
173 bool awake = false;
174 u64 val;
175
176 if (intel_gt_pm_get_if_awake(gt)) {
177 val = __get_rc6(gt);
178 intel_gt_pm_put_async(gt);
179 awake = true;
180 }
181
182 spin_lock_irqsave(&pmu->lock, flags);
183
184 if (awake) {
185 pmu->sample[__I915_SAMPLE_RC6].cur = val;
186 } else {
187 /*
188 * We think we are runtime suspended.
189 *
190 * Report the delta from when the device was suspended to now,
191 * on top of the last known real value, as the approximated RC6
192 * counter value.
193 */
194 val = ktime_since_raw(pmu->sleep_last);
195 val += pmu->sample[__I915_SAMPLE_RC6].cur;
196 }
197
198 if (val < pmu->sample[__I915_SAMPLE_RC6_LAST_REPORTED].cur)
199 val = pmu->sample[__I915_SAMPLE_RC6_LAST_REPORTED].cur;
200 else
201 pmu->sample[__I915_SAMPLE_RC6_LAST_REPORTED].cur = val;
202
203 spin_unlock_irqrestore(&pmu->lock, flags);
204
205 return val;
206}
207
208static void init_rc6(struct i915_pmu *pmu)
209{
210 struct drm_i915_private *i915 = container_of(pmu, typeof(*i915), pmu);
211 intel_wakeref_t wakeref;
212
213 with_intel_runtime_pm(i915->gt.uncore->rpm, wakeref) {
214 pmu->sample[__I915_SAMPLE_RC6].cur = __get_rc6(&i915->gt);
215 pmu->sample[__I915_SAMPLE_RC6_LAST_REPORTED].cur =
216 pmu->sample[__I915_SAMPLE_RC6].cur;
217 pmu->sleep_last = ktime_get_raw();
218 }
219}
220
221static void park_rc6(struct drm_i915_private *i915)
222{
223 struct i915_pmu *pmu = &i915->pmu;
224
225 pmu->sample[__I915_SAMPLE_RC6].cur = __get_rc6(&i915->gt);
226 pmu->sleep_last = ktime_get_raw();
227}
228
229static void __i915_pmu_maybe_start_timer(struct i915_pmu *pmu)
230{
231 if (!pmu->timer_enabled && pmu_needs_timer(pmu, true)) {
232 pmu->timer_enabled = true;
233 pmu->timer_last = ktime_get();
234 hrtimer_start_range_ns(&pmu->timer,
235 ns_to_ktime(PERIOD), 0,
236 HRTIMER_MODE_REL_PINNED);
237 }
238}
239
240void i915_pmu_gt_parked(struct drm_i915_private *i915)
241{
242 struct i915_pmu *pmu = &i915->pmu;
243
244 if (!pmu->base.event_init)
245 return;
246
247 spin_lock_irq(&pmu->lock);
248
249 park_rc6(i915);
250
251 /*
252 * Signal sampling timer to stop if only engine events are enabled and
253 * GPU went idle.
254 */
255 pmu->timer_enabled = pmu_needs_timer(pmu, false);
256
257 spin_unlock_irq(&pmu->lock);
258}
259
260void i915_pmu_gt_unparked(struct drm_i915_private *i915)
261{
262 struct i915_pmu *pmu = &i915->pmu;
263
264 if (!pmu->base.event_init)
265 return;
266
267 spin_lock_irq(&pmu->lock);
268
269 /*
270 * Re-enable sampling timer when GPU goes active.
271 */
272 __i915_pmu_maybe_start_timer(pmu);
273
274 spin_unlock_irq(&pmu->lock);
275}
276
277static void
278add_sample(struct i915_pmu_sample *sample, u32 val)
279{
280 sample->cur += val;
281}
282
283static bool exclusive_mmio_access(const struct drm_i915_private *i915)
284{
285 /*
286 * We have to avoid concurrent mmio cache line access on gen7 or
287 * risk a machine hang. For a fun history lesson dig out the old
288 * userspace intel_gpu_top and run it on Ivybridge or Haswell!
289 */
290 return GRAPHICS_VER(i915) == 7;
291}
292
293static void engine_sample(struct intel_engine_cs *engine, unsigned int period_ns)
294{
295 struct intel_engine_pmu *pmu = &engine->pmu;
296 bool busy;
297 u32 val;
298
299 val = ENGINE_READ_FW(engine, RING_CTL);
300 if (val == 0) /* powerwell off => engine idle */
301 return;
302
303 if (val & RING_WAIT)
304 add_sample(&pmu->sample[I915_SAMPLE_WAIT], period_ns);
305 if (val & RING_WAIT_SEMAPHORE)
306 add_sample(&pmu->sample[I915_SAMPLE_SEMA], period_ns);
307
308 /* No need to sample when busy stats are supported. */
309 if (intel_engine_supports_stats(engine))
310 return;
311
312 /*
313 * While waiting on a semaphore or event, MI_MODE reports the
314 * ring as idle. However, previously using the seqno, and with
315 * execlists sampling, we account for the ring waiting as the
316 * engine being busy. Therefore, we record the sample as being
317 * busy if either waiting or !idle.
318 */
319 busy = val & (RING_WAIT_SEMAPHORE | RING_WAIT);
320 if (!busy) {
321 val = ENGINE_READ_FW(engine, RING_MI_MODE);
322 busy = !(val & MODE_IDLE);
323 }
324 if (busy)
325 add_sample(&pmu->sample[I915_SAMPLE_BUSY], period_ns);
326}
327
328static void
329engines_sample(struct intel_gt *gt, unsigned int period_ns)
330{
331 struct drm_i915_private *i915 = gt->i915;
332 struct intel_engine_cs *engine;
333 enum intel_engine_id id;
334 unsigned long flags;
335
336 if ((i915->pmu.enable & ENGINE_SAMPLE_MASK) == 0)
337 return;
338
339 if (!intel_gt_pm_is_awake(gt))
340 return;
341
342 for_each_engine(engine, gt, id) {
343 if (!intel_engine_pm_get_if_awake(engine))
344 continue;
345
346 if (exclusive_mmio_access(i915)) {
347 spin_lock_irqsave(&engine->uncore->lock, flags);
348 engine_sample(engine, period_ns);
349 spin_unlock_irqrestore(&engine->uncore->lock, flags);
350 } else {
351 engine_sample(engine, period_ns);
352 }
353
354 intel_engine_pm_put_async(engine);
355 }
356}
357
358static void
359add_sample_mult(struct i915_pmu_sample *sample, u32 val, u32 mul)
360{
361 sample->cur += mul_u32_u32(val, mul);
362}
363
364static bool frequency_sampling_enabled(struct i915_pmu *pmu)
365{
366 return pmu->enable &
367 (config_mask(I915_PMU_ACTUAL_FREQUENCY) |
368 config_mask(I915_PMU_REQUESTED_FREQUENCY));
369}
370
371static void
372frequency_sample(struct intel_gt *gt, unsigned int period_ns)
373{
374 struct drm_i915_private *i915 = gt->i915;
375 struct intel_uncore *uncore = gt->uncore;
376 struct i915_pmu *pmu = &i915->pmu;
377 struct intel_rps *rps = >->rps;
378
379 if (!frequency_sampling_enabled(pmu))
380 return;
381
382 /* Report 0/0 (actual/requested) frequency while parked. */
383 if (!intel_gt_pm_get_if_awake(gt))
384 return;
385
386 if (pmu->enable & config_mask(I915_PMU_ACTUAL_FREQUENCY)) {
387 u32 val;
388
389 /*
390 * We take a quick peek here without using forcewake
391 * so that we don't perturb the system under observation
392 * (forcewake => !rc6 => increased power use). We expect
393 * that if the read fails because it is outside of the
394 * mmio power well, then it will return 0 -- in which
395 * case we assume the system is running at the intended
396 * frequency. Fortunately, the read should rarely fail!
397 */
398 val = intel_uncore_read_fw(uncore, GEN6_RPSTAT1);
399 if (val)
400 val = intel_rps_get_cagf(rps, val);
401 else
402 val = rps->cur_freq;
403
404 add_sample_mult(&pmu->sample[__I915_SAMPLE_FREQ_ACT],
405 intel_gpu_freq(rps, val), period_ns / 1000);
406 }
407
408 if (pmu->enable & config_mask(I915_PMU_REQUESTED_FREQUENCY)) {
409 add_sample_mult(&pmu->sample[__I915_SAMPLE_FREQ_REQ],
410 intel_gpu_freq(rps, rps->cur_freq),
411 period_ns / 1000);
412 }
413
414 intel_gt_pm_put_async(gt);
415}
416
417static enum hrtimer_restart i915_sample(struct hrtimer *hrtimer)
418{
419 struct drm_i915_private *i915 =
420 container_of(hrtimer, struct drm_i915_private, pmu.timer);
421 struct i915_pmu *pmu = &i915->pmu;
422 struct intel_gt *gt = &i915->gt;
423 unsigned int period_ns;
424 ktime_t now;
425
426 if (!READ_ONCE(pmu->timer_enabled))
427 return HRTIMER_NORESTART;
428
429 now = ktime_get();
430 period_ns = ktime_to_ns(ktime_sub(now, pmu->timer_last));
431 pmu->timer_last = now;
432
433 /*
434 * Strictly speaking the passed in period may not be 100% accurate for
435 * all internal calculation, since some amount of time can be spent on
436 * grabbing the forcewake. However the potential error from timer call-
437 * back delay greatly dominates this so we keep it simple.
438 */
439 engines_sample(gt, period_ns);
440 frequency_sample(gt, period_ns);
441
442 hrtimer_forward(hrtimer, now, ns_to_ktime(PERIOD));
443
444 return HRTIMER_RESTART;
445}
446
447static void i915_pmu_event_destroy(struct perf_event *event)
448{
449 struct drm_i915_private *i915 =
450 container_of(event->pmu, typeof(*i915), pmu.base);
451
452 drm_WARN_ON(&i915->drm, event->parent);
453
454 drm_dev_put(&i915->drm);
455}
456
457static int
458engine_event_status(struct intel_engine_cs *engine,
459 enum drm_i915_pmu_engine_sample sample)
460{
461 switch (sample) {
462 case I915_SAMPLE_BUSY:
463 case I915_SAMPLE_WAIT:
464 break;
465 case I915_SAMPLE_SEMA:
466 if (GRAPHICS_VER(engine->i915) < 6)
467 return -ENODEV;
468 break;
469 default:
470 return -ENOENT;
471 }
472
473 return 0;
474}
475
476static int
477config_status(struct drm_i915_private *i915, u64 config)
478{
479 struct intel_gt *gt = &i915->gt;
480
481 switch (config) {
482 case I915_PMU_ACTUAL_FREQUENCY:
483 if (IS_VALLEYVIEW(i915) || IS_CHERRYVIEW(i915))
484 /* Requires a mutex for sampling! */
485 return -ENODEV;
486 fallthrough;
487 case I915_PMU_REQUESTED_FREQUENCY:
488 if (GRAPHICS_VER(i915) < 6)
489 return -ENODEV;
490 break;
491 case I915_PMU_INTERRUPTS:
492 break;
493 case I915_PMU_RC6_RESIDENCY:
494 if (!gt->rc6.supported)
495 return -ENODEV;
496 break;
497 case I915_PMU_SOFTWARE_GT_AWAKE_TIME:
498 break;
499 default:
500 return -ENOENT;
501 }
502
503 return 0;
504}
505
506static int engine_event_init(struct perf_event *event)
507{
508 struct drm_i915_private *i915 =
509 container_of(event->pmu, typeof(*i915), pmu.base);
510 struct intel_engine_cs *engine;
511
512 engine = intel_engine_lookup_user(i915, engine_event_class(event),
513 engine_event_instance(event));
514 if (!engine)
515 return -ENODEV;
516
517 return engine_event_status(engine, engine_event_sample(event));
518}
519
520static int i915_pmu_event_init(struct perf_event *event)
521{
522 struct drm_i915_private *i915 =
523 container_of(event->pmu, typeof(*i915), pmu.base);
524 struct i915_pmu *pmu = &i915->pmu;
525 int ret;
526
527 if (pmu->closed)
528 return -ENODEV;
529
530 if (event->attr.type != event->pmu->type)
531 return -ENOENT;
532
533 /* unsupported modes and filters */
534 if (event->attr.sample_period) /* no sampling */
535 return -EINVAL;
536
537 if (has_branch_stack(event))
538 return -EOPNOTSUPP;
539
540 if (event->cpu < 0)
541 return -EINVAL;
542
543 /* only allow running on one cpu at a time */
544 if (!cpumask_test_cpu(event->cpu, &i915_pmu_cpumask))
545 return -EINVAL;
546
547 if (is_engine_event(event))
548 ret = engine_event_init(event);
549 else
550 ret = config_status(i915, event->attr.config);
551 if (ret)
552 return ret;
553
554 if (!event->parent) {
555 drm_dev_get(&i915->drm);
556 event->destroy = i915_pmu_event_destroy;
557 }
558
559 return 0;
560}
561
562static u64 __i915_pmu_event_read(struct perf_event *event)
563{
564 struct drm_i915_private *i915 =
565 container_of(event->pmu, typeof(*i915), pmu.base);
566 struct i915_pmu *pmu = &i915->pmu;
567 u64 val = 0;
568
569 if (is_engine_event(event)) {
570 u8 sample = engine_event_sample(event);
571 struct intel_engine_cs *engine;
572
573 engine = intel_engine_lookup_user(i915,
574 engine_event_class(event),
575 engine_event_instance(event));
576
577 if (drm_WARN_ON_ONCE(&i915->drm, !engine)) {
578 /* Do nothing */
579 } else if (sample == I915_SAMPLE_BUSY &&
580 intel_engine_supports_stats(engine)) {
581 ktime_t unused;
582
583 val = ktime_to_ns(intel_engine_get_busy_time(engine,
584 &unused));
585 } else {
586 val = engine->pmu.sample[sample].cur;
587 }
588 } else {
589 switch (event->attr.config) {
590 case I915_PMU_ACTUAL_FREQUENCY:
591 val =
592 div_u64(pmu->sample[__I915_SAMPLE_FREQ_ACT].cur,
593 USEC_PER_SEC /* to MHz */);
594 break;
595 case I915_PMU_REQUESTED_FREQUENCY:
596 val =
597 div_u64(pmu->sample[__I915_SAMPLE_FREQ_REQ].cur,
598 USEC_PER_SEC /* to MHz */);
599 break;
600 case I915_PMU_INTERRUPTS:
601 val = READ_ONCE(pmu->irq_count);
602 break;
603 case I915_PMU_RC6_RESIDENCY:
604 val = get_rc6(&i915->gt);
605 break;
606 case I915_PMU_SOFTWARE_GT_AWAKE_TIME:
607 val = ktime_to_ns(intel_gt_get_awake_time(&i915->gt));
608 break;
609 }
610 }
611
612 return val;
613}
614
615static void i915_pmu_event_read(struct perf_event *event)
616{
617 struct drm_i915_private *i915 =
618 container_of(event->pmu, typeof(*i915), pmu.base);
619 struct hw_perf_event *hwc = &event->hw;
620 struct i915_pmu *pmu = &i915->pmu;
621 u64 prev, new;
622
623 if (pmu->closed) {
624 event->hw.state = PERF_HES_STOPPED;
625 return;
626 }
627again:
628 prev = local64_read(&hwc->prev_count);
629 new = __i915_pmu_event_read(event);
630
631 if (local64_cmpxchg(&hwc->prev_count, prev, new) != prev)
632 goto again;
633
634 local64_add(new - prev, &event->count);
635}
636
637static void i915_pmu_enable(struct perf_event *event)
638{
639 struct drm_i915_private *i915 =
640 container_of(event->pmu, typeof(*i915), pmu.base);
641 struct i915_pmu *pmu = &i915->pmu;
642 unsigned long flags;
643 unsigned int bit;
644
645 bit = event_bit(event);
646 if (bit == -1)
647 goto update;
648
649 spin_lock_irqsave(&pmu->lock, flags);
650
651 /*
652 * Update the bitmask of enabled events and increment
653 * the event reference counter.
654 */
655 BUILD_BUG_ON(ARRAY_SIZE(pmu->enable_count) != I915_PMU_MASK_BITS);
656 GEM_BUG_ON(bit >= ARRAY_SIZE(pmu->enable_count));
657 GEM_BUG_ON(pmu->enable_count[bit] == ~0);
658
659 pmu->enable |= BIT_ULL(bit);
660 pmu->enable_count[bit]++;
661
662 /*
663 * Start the sampling timer if needed and not already enabled.
664 */
665 __i915_pmu_maybe_start_timer(pmu);
666
667 /*
668 * For per-engine events the bitmask and reference counting
669 * is stored per engine.
670 */
671 if (is_engine_event(event)) {
672 u8 sample = engine_event_sample(event);
673 struct intel_engine_cs *engine;
674
675 engine = intel_engine_lookup_user(i915,
676 engine_event_class(event),
677 engine_event_instance(event));
678
679 BUILD_BUG_ON(ARRAY_SIZE(engine->pmu.enable_count) !=
680 I915_ENGINE_SAMPLE_COUNT);
681 BUILD_BUG_ON(ARRAY_SIZE(engine->pmu.sample) !=
682 I915_ENGINE_SAMPLE_COUNT);
683 GEM_BUG_ON(sample >= ARRAY_SIZE(engine->pmu.enable_count));
684 GEM_BUG_ON(sample >= ARRAY_SIZE(engine->pmu.sample));
685 GEM_BUG_ON(engine->pmu.enable_count[sample] == ~0);
686
687 engine->pmu.enable |= BIT(sample);
688 engine->pmu.enable_count[sample]++;
689 }
690
691 spin_unlock_irqrestore(&pmu->lock, flags);
692
693update:
694 /*
695 * Store the current counter value so we can report the correct delta
696 * for all listeners. Even when the event was already enabled and has
697 * an existing non-zero value.
698 */
699 local64_set(&event->hw.prev_count, __i915_pmu_event_read(event));
700}
701
702static void i915_pmu_disable(struct perf_event *event)
703{
704 struct drm_i915_private *i915 =
705 container_of(event->pmu, typeof(*i915), pmu.base);
706 unsigned int bit = event_bit(event);
707 struct i915_pmu *pmu = &i915->pmu;
708 unsigned long flags;
709
710 if (bit == -1)
711 return;
712
713 spin_lock_irqsave(&pmu->lock, flags);
714
715 if (is_engine_event(event)) {
716 u8 sample = engine_event_sample(event);
717 struct intel_engine_cs *engine;
718
719 engine = intel_engine_lookup_user(i915,
720 engine_event_class(event),
721 engine_event_instance(event));
722
723 GEM_BUG_ON(sample >= ARRAY_SIZE(engine->pmu.enable_count));
724 GEM_BUG_ON(sample >= ARRAY_SIZE(engine->pmu.sample));
725 GEM_BUG_ON(engine->pmu.enable_count[sample] == 0);
726
727 /*
728 * Decrement the reference count and clear the enabled
729 * bitmask when the last listener on an event goes away.
730 */
731 if (--engine->pmu.enable_count[sample] == 0)
732 engine->pmu.enable &= ~BIT(sample);
733 }
734
735 GEM_BUG_ON(bit >= ARRAY_SIZE(pmu->enable_count));
736 GEM_BUG_ON(pmu->enable_count[bit] == 0);
737 /*
738 * Decrement the reference count and clear the enabled
739 * bitmask when the last listener on an event goes away.
740 */
741 if (--pmu->enable_count[bit] == 0) {
742 pmu->enable &= ~BIT_ULL(bit);
743 pmu->timer_enabled &= pmu_needs_timer(pmu, true);
744 }
745
746 spin_unlock_irqrestore(&pmu->lock, flags);
747}
748
749static void i915_pmu_event_start(struct perf_event *event, int flags)
750{
751 struct drm_i915_private *i915 =
752 container_of(event->pmu, typeof(*i915), pmu.base);
753 struct i915_pmu *pmu = &i915->pmu;
754
755 if (pmu->closed)
756 return;
757
758 i915_pmu_enable(event);
759 event->hw.state = 0;
760}
761
762static void i915_pmu_event_stop(struct perf_event *event, int flags)
763{
764 if (flags & PERF_EF_UPDATE)
765 i915_pmu_event_read(event);
766 i915_pmu_disable(event);
767 event->hw.state = PERF_HES_STOPPED;
768}
769
770static int i915_pmu_event_add(struct perf_event *event, int flags)
771{
772 struct drm_i915_private *i915 =
773 container_of(event->pmu, typeof(*i915), pmu.base);
774 struct i915_pmu *pmu = &i915->pmu;
775
776 if (pmu->closed)
777 return -ENODEV;
778
779 if (flags & PERF_EF_START)
780 i915_pmu_event_start(event, flags);
781
782 return 0;
783}
784
785static void i915_pmu_event_del(struct perf_event *event, int flags)
786{
787 i915_pmu_event_stop(event, PERF_EF_UPDATE);
788}
789
790static int i915_pmu_event_event_idx(struct perf_event *event)
791{
792 return 0;
793}
794
795struct i915_str_attribute {
796 struct device_attribute attr;
797 const char *str;
798};
799
800static ssize_t i915_pmu_format_show(struct device *dev,
801 struct device_attribute *attr, char *buf)
802{
803 struct i915_str_attribute *eattr;
804
805 eattr = container_of(attr, struct i915_str_attribute, attr);
806 return sprintf(buf, "%s\n", eattr->str);
807}
808
809#define I915_PMU_FORMAT_ATTR(_name, _config) \
810 (&((struct i915_str_attribute[]) { \
811 { .attr = __ATTR(_name, 0444, i915_pmu_format_show, NULL), \
812 .str = _config, } \
813 })[0].attr.attr)
814
815static struct attribute *i915_pmu_format_attrs[] = {
816 I915_PMU_FORMAT_ATTR(i915_eventid, "config:0-20"),
817 NULL,
818};
819
820static const struct attribute_group i915_pmu_format_attr_group = {
821 .name = "format",
822 .attrs = i915_pmu_format_attrs,
823};
824
825struct i915_ext_attribute {
826 struct device_attribute attr;
827 unsigned long val;
828};
829
830static ssize_t i915_pmu_event_show(struct device *dev,
831 struct device_attribute *attr, char *buf)
832{
833 struct i915_ext_attribute *eattr;
834
835 eattr = container_of(attr, struct i915_ext_attribute, attr);
836 return sprintf(buf, "config=0x%lx\n", eattr->val);
837}
838
839static ssize_t cpumask_show(struct device *dev,
840 struct device_attribute *attr, char *buf)
841{
842 return cpumap_print_to_pagebuf(true, buf, &i915_pmu_cpumask);
843}
844
845static DEVICE_ATTR_RO(cpumask);
846
847static struct attribute *i915_cpumask_attrs[] = {
848 &dev_attr_cpumask.attr,
849 NULL,
850};
851
852static const struct attribute_group i915_pmu_cpumask_attr_group = {
853 .attrs = i915_cpumask_attrs,
854};
855
856#define __event(__config, __name, __unit) \
857{ \
858 .config = (__config), \
859 .name = (__name), \
860 .unit = (__unit), \
861}
862
863#define __engine_event(__sample, __name) \
864{ \
865 .sample = (__sample), \
866 .name = (__name), \
867}
868
869static struct i915_ext_attribute *
870add_i915_attr(struct i915_ext_attribute *attr, const char *name, u64 config)
871{
872 sysfs_attr_init(&attr->attr.attr);
873 attr->attr.attr.name = name;
874 attr->attr.attr.mode = 0444;
875 attr->attr.show = i915_pmu_event_show;
876 attr->val = config;
877
878 return ++attr;
879}
880
881static struct perf_pmu_events_attr *
882add_pmu_attr(struct perf_pmu_events_attr *attr, const char *name,
883 const char *str)
884{
885 sysfs_attr_init(&attr->attr.attr);
886 attr->attr.attr.name = name;
887 attr->attr.attr.mode = 0444;
888 attr->attr.show = perf_event_sysfs_show;
889 attr->event_str = str;
890
891 return ++attr;
892}
893
894static struct attribute **
895create_event_attributes(struct i915_pmu *pmu)
896{
897 struct drm_i915_private *i915 = container_of(pmu, typeof(*i915), pmu);
898 static const struct {
899 u64 config;
900 const char *name;
901 const char *unit;
902 } events[] = {
903 __event(I915_PMU_ACTUAL_FREQUENCY, "actual-frequency", "M"),
904 __event(I915_PMU_REQUESTED_FREQUENCY, "requested-frequency", "M"),
905 __event(I915_PMU_INTERRUPTS, "interrupts", NULL),
906 __event(I915_PMU_RC6_RESIDENCY, "rc6-residency", "ns"),
907 __event(I915_PMU_SOFTWARE_GT_AWAKE_TIME, "software-gt-awake-time", "ns"),
908 };
909 static const struct {
910 enum drm_i915_pmu_engine_sample sample;
911 char *name;
912 } engine_events[] = {
913 __engine_event(I915_SAMPLE_BUSY, "busy"),
914 __engine_event(I915_SAMPLE_SEMA, "sema"),
915 __engine_event(I915_SAMPLE_WAIT, "wait"),
916 };
917 unsigned int count = 0;
918 struct perf_pmu_events_attr *pmu_attr = NULL, *pmu_iter;
919 struct i915_ext_attribute *i915_attr = NULL, *i915_iter;
920 struct attribute **attr = NULL, **attr_iter;
921 struct intel_engine_cs *engine;
922 unsigned int i;
923
924 /* Count how many counters we will be exposing. */
925 for (i = 0; i < ARRAY_SIZE(events); i++) {
926 if (!config_status(i915, events[i].config))
927 count++;
928 }
929
930 for_each_uabi_engine(engine, i915) {
931 for (i = 0; i < ARRAY_SIZE(engine_events); i++) {
932 if (!engine_event_status(engine,
933 engine_events[i].sample))
934 count++;
935 }
936 }
937
938 /* Allocate attribute objects and table. */
939 i915_attr = kcalloc(count, sizeof(*i915_attr), GFP_KERNEL);
940 if (!i915_attr)
941 goto err_alloc;
942
943 pmu_attr = kcalloc(count, sizeof(*pmu_attr), GFP_KERNEL);
944 if (!pmu_attr)
945 goto err_alloc;
946
947 /* Max one pointer of each attribute type plus a termination entry. */
948 attr = kcalloc(count * 2 + 1, sizeof(*attr), GFP_KERNEL);
949 if (!attr)
950 goto err_alloc;
951
952 i915_iter = i915_attr;
953 pmu_iter = pmu_attr;
954 attr_iter = attr;
955
956 /* Initialize supported non-engine counters. */
957 for (i = 0; i < ARRAY_SIZE(events); i++) {
958 char *str;
959
960 if (config_status(i915, events[i].config))
961 continue;
962
963 str = kstrdup(events[i].name, GFP_KERNEL);
964 if (!str)
965 goto err;
966
967 *attr_iter++ = &i915_iter->attr.attr;
968 i915_iter = add_i915_attr(i915_iter, str, events[i].config);
969
970 if (events[i].unit) {
971 str = kasprintf(GFP_KERNEL, "%s.unit", events[i].name);
972 if (!str)
973 goto err;
974
975 *attr_iter++ = &pmu_iter->attr.attr;
976 pmu_iter = add_pmu_attr(pmu_iter, str, events[i].unit);
977 }
978 }
979
980 /* Initialize supported engine counters. */
981 for_each_uabi_engine(engine, i915) {
982 for (i = 0; i < ARRAY_SIZE(engine_events); i++) {
983 char *str;
984
985 if (engine_event_status(engine,
986 engine_events[i].sample))
987 continue;
988
989 str = kasprintf(GFP_KERNEL, "%s-%s",
990 engine->name, engine_events[i].name);
991 if (!str)
992 goto err;
993
994 *attr_iter++ = &i915_iter->attr.attr;
995 i915_iter =
996 add_i915_attr(i915_iter, str,
997 __I915_PMU_ENGINE(engine->uabi_class,
998 engine->uabi_instance,
999 engine_events[i].sample));
1000
1001 str = kasprintf(GFP_KERNEL, "%s-%s.unit",
1002 engine->name, engine_events[i].name);
1003 if (!str)
1004 goto err;
1005
1006 *attr_iter++ = &pmu_iter->attr.attr;
1007 pmu_iter = add_pmu_attr(pmu_iter, str, "ns");
1008 }
1009 }
1010
1011 pmu->i915_attr = i915_attr;
1012 pmu->pmu_attr = pmu_attr;
1013
1014 return attr;
1015
1016err:;
1017 for (attr_iter = attr; *attr_iter; attr_iter++)
1018 kfree((*attr_iter)->name);
1019
1020err_alloc:
1021 kfree(attr);
1022 kfree(i915_attr);
1023 kfree(pmu_attr);
1024
1025 return NULL;
1026}
1027
1028static void free_event_attributes(struct i915_pmu *pmu)
1029{
1030 struct attribute **attr_iter = pmu->events_attr_group.attrs;
1031
1032 for (; *attr_iter; attr_iter++)
1033 kfree((*attr_iter)->name);
1034
1035 kfree(pmu->events_attr_group.attrs);
1036 kfree(pmu->i915_attr);
1037 kfree(pmu->pmu_attr);
1038
1039 pmu->events_attr_group.attrs = NULL;
1040 pmu->i915_attr = NULL;
1041 pmu->pmu_attr = NULL;
1042}
1043
1044static int i915_pmu_cpu_online(unsigned int cpu, struct hlist_node *node)
1045{
1046 struct i915_pmu *pmu = hlist_entry_safe(node, typeof(*pmu), cpuhp.node);
1047
1048 GEM_BUG_ON(!pmu->base.event_init);
1049
1050 /* Select the first online CPU as a designated reader. */
1051 if (!cpumask_weight(&i915_pmu_cpumask))
1052 cpumask_set_cpu(cpu, &i915_pmu_cpumask);
1053
1054 return 0;
1055}
1056
1057static int i915_pmu_cpu_offline(unsigned int cpu, struct hlist_node *node)
1058{
1059 struct i915_pmu *pmu = hlist_entry_safe(node, typeof(*pmu), cpuhp.node);
1060 unsigned int target = i915_pmu_target_cpu;
1061
1062 GEM_BUG_ON(!pmu->base.event_init);
1063
1064 /*
1065 * Unregistering an instance generates a CPU offline event which we must
1066 * ignore to avoid incorrectly modifying the shared i915_pmu_cpumask.
1067 */
1068 if (pmu->closed)
1069 return 0;
1070
1071 if (cpumask_test_and_clear_cpu(cpu, &i915_pmu_cpumask)) {
1072 target = cpumask_any_but(topology_sibling_cpumask(cpu), cpu);
1073
1074 /* Migrate events if there is a valid target */
1075 if (target < nr_cpu_ids) {
1076 cpumask_set_cpu(target, &i915_pmu_cpumask);
1077 i915_pmu_target_cpu = target;
1078 }
1079 }
1080
1081 if (target < nr_cpu_ids && target != pmu->cpuhp.cpu) {
1082 perf_pmu_migrate_context(&pmu->base, cpu, target);
1083 pmu->cpuhp.cpu = target;
1084 }
1085
1086 return 0;
1087}
1088
1089static enum cpuhp_state cpuhp_slot = CPUHP_INVALID;
1090
1091void i915_pmu_init(void)
1092{
1093 int ret;
1094
1095 ret = cpuhp_setup_state_multi(CPUHP_AP_ONLINE_DYN,
1096 "perf/x86/intel/i915:online",
1097 i915_pmu_cpu_online,
1098 i915_pmu_cpu_offline);
1099 if (ret < 0)
1100 pr_notice("Failed to setup cpuhp state for i915 PMU! (%d)\n",
1101 ret);
1102 else
1103 cpuhp_slot = ret;
1104}
1105
1106void i915_pmu_exit(void)
1107{
1108 if (cpuhp_slot != CPUHP_INVALID)
1109 cpuhp_remove_multi_state(cpuhp_slot);
1110}
1111
1112static int i915_pmu_register_cpuhp_state(struct i915_pmu *pmu)
1113{
1114 if (cpuhp_slot == CPUHP_INVALID)
1115 return -EINVAL;
1116
1117 return cpuhp_state_add_instance(cpuhp_slot, &pmu->cpuhp.node);
1118}
1119
1120static void i915_pmu_unregister_cpuhp_state(struct i915_pmu *pmu)
1121{
1122 cpuhp_state_remove_instance(cpuhp_slot, &pmu->cpuhp.node);
1123}
1124
1125static bool is_igp(struct drm_i915_private *i915)
1126{
1127 struct pci_dev *pdev = to_pci_dev(i915->drm.dev);
1128
1129 /* IGP is 0000:00:02.0 */
1130 return pci_domain_nr(pdev->bus) == 0 &&
1131 pdev->bus->number == 0 &&
1132 PCI_SLOT(pdev->devfn) == 2 &&
1133 PCI_FUNC(pdev->devfn) == 0;
1134}
1135
1136void i915_pmu_register(struct drm_i915_private *i915)
1137{
1138 struct i915_pmu *pmu = &i915->pmu;
1139 const struct attribute_group *attr_groups[] = {
1140 &i915_pmu_format_attr_group,
1141 &pmu->events_attr_group,
1142 &i915_pmu_cpumask_attr_group,
1143 NULL
1144 };
1145
1146 int ret = -ENOMEM;
1147
1148 if (GRAPHICS_VER(i915) <= 2) {
1149 drm_info(&i915->drm, "PMU not supported for this GPU.");
1150 return;
1151 }
1152
1153 spin_lock_init(&pmu->lock);
1154 hrtimer_init(&pmu->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
1155 pmu->timer.function = i915_sample;
1156 pmu->cpuhp.cpu = -1;
1157 init_rc6(pmu);
1158
1159 if (!is_igp(i915)) {
1160 pmu->name = kasprintf(GFP_KERNEL,
1161 "i915_%s",
1162 dev_name(i915->drm.dev));
1163 if (pmu->name) {
1164 /* tools/perf reserves colons as special. */
1165 strreplace((char *)pmu->name, ':', '_');
1166 }
1167 } else {
1168 pmu->name = "i915";
1169 }
1170 if (!pmu->name)
1171 goto err;
1172
1173 pmu->events_attr_group.name = "events";
1174 pmu->events_attr_group.attrs = create_event_attributes(pmu);
1175 if (!pmu->events_attr_group.attrs)
1176 goto err_name;
1177
1178 pmu->base.attr_groups = kmemdup(attr_groups, sizeof(attr_groups),
1179 GFP_KERNEL);
1180 if (!pmu->base.attr_groups)
1181 goto err_attr;
1182
1183 pmu->base.module = THIS_MODULE;
1184 pmu->base.task_ctx_nr = perf_invalid_context;
1185 pmu->base.event_init = i915_pmu_event_init;
1186 pmu->base.add = i915_pmu_event_add;
1187 pmu->base.del = i915_pmu_event_del;
1188 pmu->base.start = i915_pmu_event_start;
1189 pmu->base.stop = i915_pmu_event_stop;
1190 pmu->base.read = i915_pmu_event_read;
1191 pmu->base.event_idx = i915_pmu_event_event_idx;
1192
1193 ret = perf_pmu_register(&pmu->base, pmu->name, -1);
1194 if (ret)
1195 goto err_groups;
1196
1197 ret = i915_pmu_register_cpuhp_state(pmu);
1198 if (ret)
1199 goto err_unreg;
1200
1201 return;
1202
1203err_unreg:
1204 perf_pmu_unregister(&pmu->base);
1205err_groups:
1206 kfree(pmu->base.attr_groups);
1207err_attr:
1208 pmu->base.event_init = NULL;
1209 free_event_attributes(pmu);
1210err_name:
1211 if (!is_igp(i915))
1212 kfree(pmu->name);
1213err:
1214 drm_notice(&i915->drm, "Failed to register PMU!\n");
1215}
1216
1217void i915_pmu_unregister(struct drm_i915_private *i915)
1218{
1219 struct i915_pmu *pmu = &i915->pmu;
1220
1221 if (!pmu->base.event_init)
1222 return;
1223
1224 /*
1225 * "Disconnect" the PMU callbacks - since all are atomic synchronize_rcu
1226 * ensures all currently executing ones will have exited before we
1227 * proceed with unregistration.
1228 */
1229 pmu->closed = true;
1230 synchronize_rcu();
1231
1232 hrtimer_cancel(&pmu->timer);
1233
1234 i915_pmu_unregister_cpuhp_state(pmu);
1235
1236 perf_pmu_unregister(&pmu->base);
1237 pmu->base.event_init = NULL;
1238 kfree(pmu->base.attr_groups);
1239 if (!is_igp(i915))
1240 kfree(pmu->name);
1241 free_event_attributes(pmu);
1242}