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1/*
2 * perf_event_intel_rapl.c: support Intel RAPL energy consumption counters
3 * Copyright (C) 2013 Google, Inc., Stephane Eranian
4 *
5 * Intel RAPL interface is specified in the IA-32 Manual Vol3b
6 * section 14.7.1 (September 2013)
7 *
8 * RAPL provides more controls than just reporting energy consumption
9 * however here we only expose the 3 energy consumption free running
10 * counters (pp0, pkg, dram).
11 *
12 * Each of those counters increments in a power unit defined by the
13 * RAPL_POWER_UNIT MSR. On SandyBridge, this unit is 1/(2^16) Joules
14 * but it can vary.
15 *
16 * Counter to rapl events mappings:
17 *
18 * pp0 counter: consumption of all physical cores (power plane 0)
19 * event: rapl_energy_cores
20 * perf code: 0x1
21 *
22 * pkg counter: consumption of the whole processor package
23 * event: rapl_energy_pkg
24 * perf code: 0x2
25 *
26 * dram counter: consumption of the dram domain (servers only)
27 * event: rapl_energy_dram
28 * perf code: 0x3
29 *
30 * dram counter: consumption of the builtin-gpu domain (client only)
31 * event: rapl_energy_gpu
32 * perf code: 0x4
33 *
34 * We manage those counters as free running (read-only). They may be
35 * use simultaneously by other tools, such as turbostat.
36 *
37 * The events only support system-wide mode counting. There is no
38 * sampling support because it does not make sense and is not
39 * supported by the RAPL hardware.
40 *
41 * Because we want to avoid floating-point operations in the kernel,
42 * the events are all reported in fixed point arithmetic (32.32).
43 * Tools must adjust the counts to convert them to Watts using
44 * the duration of the measurement. Tools may use a function such as
45 * ldexp(raw_count, -32);
46 */
47#include <linux/module.h>
48#include <linux/slab.h>
49#include <linux/perf_event.h>
50#include <asm/cpu_device_id.h>
51#include "perf_event.h"
52
53/*
54 * RAPL energy status counters
55 */
56#define RAPL_IDX_PP0_NRG_STAT 0 /* all cores */
57#define INTEL_RAPL_PP0 0x1 /* pseudo-encoding */
58#define RAPL_IDX_PKG_NRG_STAT 1 /* entire package */
59#define INTEL_RAPL_PKG 0x2 /* pseudo-encoding */
60#define RAPL_IDX_RAM_NRG_STAT 2 /* DRAM */
61#define INTEL_RAPL_RAM 0x3 /* pseudo-encoding */
62#define RAPL_IDX_PP1_NRG_STAT 3 /* gpu */
63#define INTEL_RAPL_PP1 0x4 /* pseudo-encoding */
64
65/* Clients have PP0, PKG */
66#define RAPL_IDX_CLN (1<<RAPL_IDX_PP0_NRG_STAT|\
67 1<<RAPL_IDX_PKG_NRG_STAT|\
68 1<<RAPL_IDX_PP1_NRG_STAT)
69
70/* Servers have PP0, PKG, RAM */
71#define RAPL_IDX_SRV (1<<RAPL_IDX_PP0_NRG_STAT|\
72 1<<RAPL_IDX_PKG_NRG_STAT|\
73 1<<RAPL_IDX_RAM_NRG_STAT)
74
75/* Servers have PP0, PKG, RAM, PP1 */
76#define RAPL_IDX_HSW (1<<RAPL_IDX_PP0_NRG_STAT|\
77 1<<RAPL_IDX_PKG_NRG_STAT|\
78 1<<RAPL_IDX_RAM_NRG_STAT|\
79 1<<RAPL_IDX_PP1_NRG_STAT)
80
81/*
82 * event code: LSB 8 bits, passed in attr->config
83 * any other bit is reserved
84 */
85#define RAPL_EVENT_MASK 0xFFULL
86
87#define DEFINE_RAPL_FORMAT_ATTR(_var, _name, _format) \
88static ssize_t __rapl_##_var##_show(struct kobject *kobj, \
89 struct kobj_attribute *attr, \
90 char *page) \
91{ \
92 BUILD_BUG_ON(sizeof(_format) >= PAGE_SIZE); \
93 return sprintf(page, _format "\n"); \
94} \
95static struct kobj_attribute format_attr_##_var = \
96 __ATTR(_name, 0444, __rapl_##_var##_show, NULL)
97
98#define RAPL_EVENT_DESC(_name, _config) \
99{ \
100 .attr = __ATTR(_name, 0444, rapl_event_show, NULL), \
101 .config = _config, \
102}
103
104#define RAPL_CNTR_WIDTH 32 /* 32-bit rapl counters */
105
106struct rapl_pmu {
107 spinlock_t lock;
108 int hw_unit; /* 1/2^hw_unit Joule */
109 int n_active; /* number of active events */
110 struct list_head active_list;
111 struct pmu *pmu; /* pointer to rapl_pmu_class */
112 ktime_t timer_interval; /* in ktime_t unit */
113 struct hrtimer hrtimer;
114};
115
116static struct pmu rapl_pmu_class;
117static cpumask_t rapl_cpu_mask;
118static int rapl_cntr_mask;
119
120static DEFINE_PER_CPU(struct rapl_pmu *, rapl_pmu);
121static DEFINE_PER_CPU(struct rapl_pmu *, rapl_pmu_to_free);
122
123static inline u64 rapl_read_counter(struct perf_event *event)
124{
125 u64 raw;
126 rdmsrl(event->hw.event_base, raw);
127 return raw;
128}
129
130static inline u64 rapl_scale(u64 v)
131{
132 /*
133 * scale delta to smallest unit (1/2^32)
134 * users must then scale back: count * 1/(1e9*2^32) to get Joules
135 * or use ldexp(count, -32).
136 * Watts = Joules/Time delta
137 */
138 return v << (32 - __get_cpu_var(rapl_pmu)->hw_unit);
139}
140
141static u64 rapl_event_update(struct perf_event *event)
142{
143 struct hw_perf_event *hwc = &event->hw;
144 u64 prev_raw_count, new_raw_count;
145 s64 delta, sdelta;
146 int shift = RAPL_CNTR_WIDTH;
147
148again:
149 prev_raw_count = local64_read(&hwc->prev_count);
150 rdmsrl(event->hw.event_base, new_raw_count);
151
152 if (local64_cmpxchg(&hwc->prev_count, prev_raw_count,
153 new_raw_count) != prev_raw_count) {
154 cpu_relax();
155 goto again;
156 }
157
158 /*
159 * Now we have the new raw value and have updated the prev
160 * timestamp already. We can now calculate the elapsed delta
161 * (event-)time and add that to the generic event.
162 *
163 * Careful, not all hw sign-extends above the physical width
164 * of the count.
165 */
166 delta = (new_raw_count << shift) - (prev_raw_count << shift);
167 delta >>= shift;
168
169 sdelta = rapl_scale(delta);
170
171 local64_add(sdelta, &event->count);
172
173 return new_raw_count;
174}
175
176static void rapl_start_hrtimer(struct rapl_pmu *pmu)
177{
178 __hrtimer_start_range_ns(&pmu->hrtimer,
179 pmu->timer_interval, 0,
180 HRTIMER_MODE_REL_PINNED, 0);
181}
182
183static void rapl_stop_hrtimer(struct rapl_pmu *pmu)
184{
185 hrtimer_cancel(&pmu->hrtimer);
186}
187
188static enum hrtimer_restart rapl_hrtimer_handle(struct hrtimer *hrtimer)
189{
190 struct rapl_pmu *pmu = __get_cpu_var(rapl_pmu);
191 struct perf_event *event;
192 unsigned long flags;
193
194 if (!pmu->n_active)
195 return HRTIMER_NORESTART;
196
197 spin_lock_irqsave(&pmu->lock, flags);
198
199 list_for_each_entry(event, &pmu->active_list, active_entry) {
200 rapl_event_update(event);
201 }
202
203 spin_unlock_irqrestore(&pmu->lock, flags);
204
205 hrtimer_forward_now(hrtimer, pmu->timer_interval);
206
207 return HRTIMER_RESTART;
208}
209
210static void rapl_hrtimer_init(struct rapl_pmu *pmu)
211{
212 struct hrtimer *hr = &pmu->hrtimer;
213
214 hrtimer_init(hr, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
215 hr->function = rapl_hrtimer_handle;
216}
217
218static void __rapl_pmu_event_start(struct rapl_pmu *pmu,
219 struct perf_event *event)
220{
221 if (WARN_ON_ONCE(!(event->hw.state & PERF_HES_STOPPED)))
222 return;
223
224 event->hw.state = 0;
225
226 list_add_tail(&event->active_entry, &pmu->active_list);
227
228 local64_set(&event->hw.prev_count, rapl_read_counter(event));
229
230 pmu->n_active++;
231 if (pmu->n_active == 1)
232 rapl_start_hrtimer(pmu);
233}
234
235static void rapl_pmu_event_start(struct perf_event *event, int mode)
236{
237 struct rapl_pmu *pmu = __get_cpu_var(rapl_pmu);
238 unsigned long flags;
239
240 spin_lock_irqsave(&pmu->lock, flags);
241 __rapl_pmu_event_start(pmu, event);
242 spin_unlock_irqrestore(&pmu->lock, flags);
243}
244
245static void rapl_pmu_event_stop(struct perf_event *event, int mode)
246{
247 struct rapl_pmu *pmu = __get_cpu_var(rapl_pmu);
248 struct hw_perf_event *hwc = &event->hw;
249 unsigned long flags;
250
251 spin_lock_irqsave(&pmu->lock, flags);
252
253 /* mark event as deactivated and stopped */
254 if (!(hwc->state & PERF_HES_STOPPED)) {
255 WARN_ON_ONCE(pmu->n_active <= 0);
256 pmu->n_active--;
257 if (pmu->n_active == 0)
258 rapl_stop_hrtimer(pmu);
259
260 list_del(&event->active_entry);
261
262 WARN_ON_ONCE(hwc->state & PERF_HES_STOPPED);
263 hwc->state |= PERF_HES_STOPPED;
264 }
265
266 /* check if update of sw counter is necessary */
267 if ((mode & PERF_EF_UPDATE) && !(hwc->state & PERF_HES_UPTODATE)) {
268 /*
269 * Drain the remaining delta count out of a event
270 * that we are disabling:
271 */
272 rapl_event_update(event);
273 hwc->state |= PERF_HES_UPTODATE;
274 }
275
276 spin_unlock_irqrestore(&pmu->lock, flags);
277}
278
279static int rapl_pmu_event_add(struct perf_event *event, int mode)
280{
281 struct rapl_pmu *pmu = __get_cpu_var(rapl_pmu);
282 struct hw_perf_event *hwc = &event->hw;
283 unsigned long flags;
284
285 spin_lock_irqsave(&pmu->lock, flags);
286
287 hwc->state = PERF_HES_UPTODATE | PERF_HES_STOPPED;
288
289 if (mode & PERF_EF_START)
290 __rapl_pmu_event_start(pmu, event);
291
292 spin_unlock_irqrestore(&pmu->lock, flags);
293
294 return 0;
295}
296
297static void rapl_pmu_event_del(struct perf_event *event, int flags)
298{
299 rapl_pmu_event_stop(event, PERF_EF_UPDATE);
300}
301
302static int rapl_pmu_event_init(struct perf_event *event)
303{
304 u64 cfg = event->attr.config & RAPL_EVENT_MASK;
305 int bit, msr, ret = 0;
306
307 /* only look at RAPL events */
308 if (event->attr.type != rapl_pmu_class.type)
309 return -ENOENT;
310
311 /* check only supported bits are set */
312 if (event->attr.config & ~RAPL_EVENT_MASK)
313 return -EINVAL;
314
315 /*
316 * check event is known (determines counter)
317 */
318 switch (cfg) {
319 case INTEL_RAPL_PP0:
320 bit = RAPL_IDX_PP0_NRG_STAT;
321 msr = MSR_PP0_ENERGY_STATUS;
322 break;
323 case INTEL_RAPL_PKG:
324 bit = RAPL_IDX_PKG_NRG_STAT;
325 msr = MSR_PKG_ENERGY_STATUS;
326 break;
327 case INTEL_RAPL_RAM:
328 bit = RAPL_IDX_RAM_NRG_STAT;
329 msr = MSR_DRAM_ENERGY_STATUS;
330 break;
331 case INTEL_RAPL_PP1:
332 bit = RAPL_IDX_PP1_NRG_STAT;
333 msr = MSR_PP1_ENERGY_STATUS;
334 break;
335 default:
336 return -EINVAL;
337 }
338 /* check event supported */
339 if (!(rapl_cntr_mask & (1 << bit)))
340 return -EINVAL;
341
342 /* unsupported modes and filters */
343 if (event->attr.exclude_user ||
344 event->attr.exclude_kernel ||
345 event->attr.exclude_hv ||
346 event->attr.exclude_idle ||
347 event->attr.exclude_host ||
348 event->attr.exclude_guest ||
349 event->attr.sample_period) /* no sampling */
350 return -EINVAL;
351
352 /* must be done before validate_group */
353 event->hw.event_base = msr;
354 event->hw.config = cfg;
355 event->hw.idx = bit;
356
357 return ret;
358}
359
360static void rapl_pmu_event_read(struct perf_event *event)
361{
362 rapl_event_update(event);
363}
364
365static ssize_t rapl_get_attr_cpumask(struct device *dev,
366 struct device_attribute *attr, char *buf)
367{
368 int n = cpulist_scnprintf(buf, PAGE_SIZE - 2, &rapl_cpu_mask);
369
370 buf[n++] = '\n';
371 buf[n] = '\0';
372 return n;
373}
374
375static DEVICE_ATTR(cpumask, S_IRUGO, rapl_get_attr_cpumask, NULL);
376
377static struct attribute *rapl_pmu_attrs[] = {
378 &dev_attr_cpumask.attr,
379 NULL,
380};
381
382static struct attribute_group rapl_pmu_attr_group = {
383 .attrs = rapl_pmu_attrs,
384};
385
386EVENT_ATTR_STR(energy-cores, rapl_cores, "event=0x01");
387EVENT_ATTR_STR(energy-pkg , rapl_pkg, "event=0x02");
388EVENT_ATTR_STR(energy-ram , rapl_ram, "event=0x03");
389EVENT_ATTR_STR(energy-gpu , rapl_gpu, "event=0x04");
390
391EVENT_ATTR_STR(energy-cores.unit, rapl_cores_unit, "Joules");
392EVENT_ATTR_STR(energy-pkg.unit , rapl_pkg_unit, "Joules");
393EVENT_ATTR_STR(energy-ram.unit , rapl_ram_unit, "Joules");
394EVENT_ATTR_STR(energy-gpu.unit , rapl_gpu_unit, "Joules");
395
396/*
397 * we compute in 0.23 nJ increments regardless of MSR
398 */
399EVENT_ATTR_STR(energy-cores.scale, rapl_cores_scale, "2.3283064365386962890625e-10");
400EVENT_ATTR_STR(energy-pkg.scale, rapl_pkg_scale, "2.3283064365386962890625e-10");
401EVENT_ATTR_STR(energy-ram.scale, rapl_ram_scale, "2.3283064365386962890625e-10");
402EVENT_ATTR_STR(energy-gpu.scale, rapl_gpu_scale, "2.3283064365386962890625e-10");
403
404static struct attribute *rapl_events_srv_attr[] = {
405 EVENT_PTR(rapl_cores),
406 EVENT_PTR(rapl_pkg),
407 EVENT_PTR(rapl_ram),
408
409 EVENT_PTR(rapl_cores_unit),
410 EVENT_PTR(rapl_pkg_unit),
411 EVENT_PTR(rapl_ram_unit),
412
413 EVENT_PTR(rapl_cores_scale),
414 EVENT_PTR(rapl_pkg_scale),
415 EVENT_PTR(rapl_ram_scale),
416 NULL,
417};
418
419static struct attribute *rapl_events_cln_attr[] = {
420 EVENT_PTR(rapl_cores),
421 EVENT_PTR(rapl_pkg),
422 EVENT_PTR(rapl_gpu),
423
424 EVENT_PTR(rapl_cores_unit),
425 EVENT_PTR(rapl_pkg_unit),
426 EVENT_PTR(rapl_gpu_unit),
427
428 EVENT_PTR(rapl_cores_scale),
429 EVENT_PTR(rapl_pkg_scale),
430 EVENT_PTR(rapl_gpu_scale),
431 NULL,
432};
433
434static struct attribute *rapl_events_hsw_attr[] = {
435 EVENT_PTR(rapl_cores),
436 EVENT_PTR(rapl_pkg),
437 EVENT_PTR(rapl_gpu),
438 EVENT_PTR(rapl_ram),
439
440 EVENT_PTR(rapl_cores_unit),
441 EVENT_PTR(rapl_pkg_unit),
442 EVENT_PTR(rapl_gpu_unit),
443 EVENT_PTR(rapl_ram_unit),
444
445 EVENT_PTR(rapl_cores_scale),
446 EVENT_PTR(rapl_pkg_scale),
447 EVENT_PTR(rapl_gpu_scale),
448 EVENT_PTR(rapl_ram_scale),
449 NULL,
450};
451
452static struct attribute_group rapl_pmu_events_group = {
453 .name = "events",
454 .attrs = NULL, /* patched at runtime */
455};
456
457DEFINE_RAPL_FORMAT_ATTR(event, event, "config:0-7");
458static struct attribute *rapl_formats_attr[] = {
459 &format_attr_event.attr,
460 NULL,
461};
462
463static struct attribute_group rapl_pmu_format_group = {
464 .name = "format",
465 .attrs = rapl_formats_attr,
466};
467
468const struct attribute_group *rapl_attr_groups[] = {
469 &rapl_pmu_attr_group,
470 &rapl_pmu_format_group,
471 &rapl_pmu_events_group,
472 NULL,
473};
474
475static struct pmu rapl_pmu_class = {
476 .attr_groups = rapl_attr_groups,
477 .task_ctx_nr = perf_invalid_context, /* system-wide only */
478 .event_init = rapl_pmu_event_init,
479 .add = rapl_pmu_event_add, /* must have */
480 .del = rapl_pmu_event_del, /* must have */
481 .start = rapl_pmu_event_start,
482 .stop = rapl_pmu_event_stop,
483 .read = rapl_pmu_event_read,
484};
485
486static void rapl_cpu_exit(int cpu)
487{
488 struct rapl_pmu *pmu = per_cpu(rapl_pmu, cpu);
489 int i, phys_id = topology_physical_package_id(cpu);
490 int target = -1;
491
492 /* find a new cpu on same package */
493 for_each_online_cpu(i) {
494 if (i == cpu)
495 continue;
496 if (phys_id == topology_physical_package_id(i)) {
497 target = i;
498 break;
499 }
500 }
501 /*
502 * clear cpu from cpumask
503 * if was set in cpumask and still some cpu on package,
504 * then move to new cpu
505 */
506 if (cpumask_test_and_clear_cpu(cpu, &rapl_cpu_mask) && target >= 0)
507 cpumask_set_cpu(target, &rapl_cpu_mask);
508
509 WARN_ON(cpumask_empty(&rapl_cpu_mask));
510 /*
511 * migrate events and context to new cpu
512 */
513 if (target >= 0)
514 perf_pmu_migrate_context(pmu->pmu, cpu, target);
515
516 /* cancel overflow polling timer for CPU */
517 rapl_stop_hrtimer(pmu);
518}
519
520static void rapl_cpu_init(int cpu)
521{
522 int i, phys_id = topology_physical_package_id(cpu);
523
524 /* check if phys_is is already covered */
525 for_each_cpu(i, &rapl_cpu_mask) {
526 if (phys_id == topology_physical_package_id(i))
527 return;
528 }
529 /* was not found, so add it */
530 cpumask_set_cpu(cpu, &rapl_cpu_mask);
531}
532
533static int rapl_cpu_prepare(int cpu)
534{
535 struct rapl_pmu *pmu = per_cpu(rapl_pmu, cpu);
536 int phys_id = topology_physical_package_id(cpu);
537 u64 ms;
538 u64 msr_rapl_power_unit_bits;
539
540 if (pmu)
541 return 0;
542
543 if (phys_id < 0)
544 return -1;
545
546 /* protect rdmsrl() to handle virtualization */
547 if (rdmsrl_safe(MSR_RAPL_POWER_UNIT, &msr_rapl_power_unit_bits))
548 return -1;
549
550 pmu = kzalloc_node(sizeof(*pmu), GFP_KERNEL, cpu_to_node(cpu));
551 if (!pmu)
552 return -1;
553
554 spin_lock_init(&pmu->lock);
555
556 INIT_LIST_HEAD(&pmu->active_list);
557
558 /*
559 * grab power unit as: 1/2^unit Joules
560 *
561 * we cache in local PMU instance
562 */
563 pmu->hw_unit = (msr_rapl_power_unit_bits >> 8) & 0x1FULL;
564 pmu->pmu = &rapl_pmu_class;
565
566 /*
567 * use reference of 200W for scaling the timeout
568 * to avoid missing counter overflows.
569 * 200W = 200 Joules/sec
570 * divide interval by 2 to avoid lockstep (2 * 100)
571 * if hw unit is 32, then we use 2 ms 1/200/2
572 */
573 if (pmu->hw_unit < 32)
574 ms = (1000 / (2 * 100)) * (1ULL << (32 - pmu->hw_unit - 1));
575 else
576 ms = 2;
577
578 pmu->timer_interval = ms_to_ktime(ms);
579
580 rapl_hrtimer_init(pmu);
581
582 /* set RAPL pmu for this cpu for now */
583 per_cpu(rapl_pmu, cpu) = pmu;
584 per_cpu(rapl_pmu_to_free, cpu) = NULL;
585
586 return 0;
587}
588
589static void rapl_cpu_kfree(int cpu)
590{
591 struct rapl_pmu *pmu = per_cpu(rapl_pmu_to_free, cpu);
592
593 kfree(pmu);
594
595 per_cpu(rapl_pmu_to_free, cpu) = NULL;
596}
597
598static int rapl_cpu_dying(int cpu)
599{
600 struct rapl_pmu *pmu = per_cpu(rapl_pmu, cpu);
601
602 if (!pmu)
603 return 0;
604
605 per_cpu(rapl_pmu, cpu) = NULL;
606
607 per_cpu(rapl_pmu_to_free, cpu) = pmu;
608
609 return 0;
610}
611
612static int rapl_cpu_notifier(struct notifier_block *self,
613 unsigned long action, void *hcpu)
614{
615 unsigned int cpu = (long)hcpu;
616
617 switch (action & ~CPU_TASKS_FROZEN) {
618 case CPU_UP_PREPARE:
619 rapl_cpu_prepare(cpu);
620 break;
621 case CPU_STARTING:
622 rapl_cpu_init(cpu);
623 break;
624 case CPU_UP_CANCELED:
625 case CPU_DYING:
626 rapl_cpu_dying(cpu);
627 break;
628 case CPU_ONLINE:
629 case CPU_DEAD:
630 rapl_cpu_kfree(cpu);
631 break;
632 case CPU_DOWN_PREPARE:
633 rapl_cpu_exit(cpu);
634 break;
635 default:
636 break;
637 }
638
639 return NOTIFY_OK;
640}
641
642static const struct x86_cpu_id rapl_cpu_match[] = {
643 [0] = { .vendor = X86_VENDOR_INTEL, .family = 6 },
644 [1] = {},
645};
646
647static int __init rapl_pmu_init(void)
648{
649 struct rapl_pmu *pmu;
650 int cpu, ret;
651
652 /*
653 * check for Intel processor family 6
654 */
655 if (!x86_match_cpu(rapl_cpu_match))
656 return 0;
657
658 /* check supported CPU */
659 switch (boot_cpu_data.x86_model) {
660 case 42: /* Sandy Bridge */
661 case 58: /* Ivy Bridge */
662 rapl_cntr_mask = RAPL_IDX_CLN;
663 rapl_pmu_events_group.attrs = rapl_events_cln_attr;
664 break;
665 case 60: /* Haswell */
666 case 69: /* Haswell-Celeron */
667 rapl_cntr_mask = RAPL_IDX_HSW;
668 rapl_pmu_events_group.attrs = rapl_events_hsw_attr;
669 break;
670 case 45: /* Sandy Bridge-EP */
671 case 62: /* IvyTown */
672 rapl_cntr_mask = RAPL_IDX_SRV;
673 rapl_pmu_events_group.attrs = rapl_events_srv_attr;
674 break;
675
676 default:
677 /* unsupported */
678 return 0;
679 }
680
681 cpu_notifier_register_begin();
682
683 for_each_online_cpu(cpu) {
684 ret = rapl_cpu_prepare(cpu);
685 if (ret)
686 goto out;
687 rapl_cpu_init(cpu);
688 }
689
690 __perf_cpu_notifier(rapl_cpu_notifier);
691
692 ret = perf_pmu_register(&rapl_pmu_class, "power", -1);
693 if (WARN_ON(ret)) {
694 pr_info("RAPL PMU detected, registration failed (%d), RAPL PMU disabled\n", ret);
695 cpu_notifier_register_done();
696 return -1;
697 }
698
699 pmu = __get_cpu_var(rapl_pmu);
700
701 pr_info("RAPL PMU detected, hw unit 2^-%d Joules,"
702 " API unit is 2^-32 Joules,"
703 " %d fixed counters"
704 " %llu ms ovfl timer\n",
705 pmu->hw_unit,
706 hweight32(rapl_cntr_mask),
707 ktime_to_ms(pmu->timer_interval));
708
709out:
710 cpu_notifier_register_done();
711
712 return 0;
713}
714device_initcall(rapl_pmu_init);