spi: sirf: Add missing spi_master_{resume,suspend} calls to PM callbacks
[cascardo/linux.git] / arch / x86 / kernel / cpu / perf_event.c
1 /*
2  * Performance events x86 architecture code
3  *
4  *  Copyright (C) 2008 Thomas Gleixner <tglx@linutronix.de>
5  *  Copyright (C) 2008-2009 Red Hat, Inc., Ingo Molnar
6  *  Copyright (C) 2009 Jaswinder Singh Rajput
7  *  Copyright (C) 2009 Advanced Micro Devices, Inc., Robert Richter
8  *  Copyright (C) 2008-2009 Red Hat, Inc., Peter Zijlstra <pzijlstr@redhat.com>
9  *  Copyright (C) 2009 Intel Corporation, <markus.t.metzger@intel.com>
10  *  Copyright (C) 2009 Google, Inc., Stephane Eranian
11  *
12  *  For licencing details see kernel-base/COPYING
13  */
14
15 #include <linux/perf_event.h>
16 #include <linux/capability.h>
17 #include <linux/notifier.h>
18 #include <linux/hardirq.h>
19 #include <linux/kprobes.h>
20 #include <linux/module.h>
21 #include <linux/kdebug.h>
22 #include <linux/sched.h>
23 #include <linux/uaccess.h>
24 #include <linux/slab.h>
25 #include <linux/cpu.h>
26 #include <linux/bitops.h>
27 #include <linux/device.h>
28
29 #include <asm/apic.h>
30 #include <asm/stacktrace.h>
31 #include <asm/nmi.h>
32 #include <asm/smp.h>
33 #include <asm/alternative.h>
34 #include <asm/timer.h>
35 #include <asm/desc.h>
36 #include <asm/ldt.h>
37
38 #include "perf_event.h"
39
40 struct x86_pmu x86_pmu __read_mostly;
41
42 DEFINE_PER_CPU(struct cpu_hw_events, cpu_hw_events) = {
43         .enabled = 1,
44 };
45
46 u64 __read_mostly hw_cache_event_ids
47                                 [PERF_COUNT_HW_CACHE_MAX]
48                                 [PERF_COUNT_HW_CACHE_OP_MAX]
49                                 [PERF_COUNT_HW_CACHE_RESULT_MAX];
50 u64 __read_mostly hw_cache_extra_regs
51                                 [PERF_COUNT_HW_CACHE_MAX]
52                                 [PERF_COUNT_HW_CACHE_OP_MAX]
53                                 [PERF_COUNT_HW_CACHE_RESULT_MAX];
54
55 /*
56  * Propagate event elapsed time into the generic event.
57  * Can only be executed on the CPU where the event is active.
58  * Returns the delta events processed.
59  */
60 u64 x86_perf_event_update(struct perf_event *event)
61 {
62         struct hw_perf_event *hwc = &event->hw;
63         int shift = 64 - x86_pmu.cntval_bits;
64         u64 prev_raw_count, new_raw_count;
65         int idx = hwc->idx;
66         s64 delta;
67
68         if (idx == INTEL_PMC_IDX_FIXED_BTS)
69                 return 0;
70
71         /*
72          * Careful: an NMI might modify the previous event value.
73          *
74          * Our tactic to handle this is to first atomically read and
75          * exchange a new raw count - then add that new-prev delta
76          * count to the generic event atomically:
77          */
78 again:
79         prev_raw_count = local64_read(&hwc->prev_count);
80         rdpmcl(hwc->event_base_rdpmc, new_raw_count);
81
82         if (local64_cmpxchg(&hwc->prev_count, prev_raw_count,
83                                         new_raw_count) != prev_raw_count)
84                 goto again;
85
86         /*
87          * Now we have the new raw value and have updated the prev
88          * timestamp already. We can now calculate the elapsed delta
89          * (event-)time and add that to the generic event.
90          *
91          * Careful, not all hw sign-extends above the physical width
92          * of the count.
93          */
94         delta = (new_raw_count << shift) - (prev_raw_count << shift);
95         delta >>= shift;
96
97         local64_add(delta, &event->count);
98         local64_sub(delta, &hwc->period_left);
99
100         return new_raw_count;
101 }
102
103 /*
104  * Find and validate any extra registers to set up.
105  */
106 static int x86_pmu_extra_regs(u64 config, struct perf_event *event)
107 {
108         struct hw_perf_event_extra *reg;
109         struct extra_reg *er;
110
111         reg = &event->hw.extra_reg;
112
113         if (!x86_pmu.extra_regs)
114                 return 0;
115
116         for (er = x86_pmu.extra_regs; er->msr; er++) {
117                 if (er->event != (config & er->config_mask))
118                         continue;
119                 if (event->attr.config1 & ~er->valid_mask)
120                         return -EINVAL;
121
122                 reg->idx = er->idx;
123                 reg->config = event->attr.config1;
124                 reg->reg = er->msr;
125                 break;
126         }
127         return 0;
128 }
129
130 static atomic_t active_events;
131 static DEFINE_MUTEX(pmc_reserve_mutex);
132
133 #ifdef CONFIG_X86_LOCAL_APIC
134
135 static bool reserve_pmc_hardware(void)
136 {
137         int i;
138
139         for (i = 0; i < x86_pmu.num_counters; i++) {
140                 if (!reserve_perfctr_nmi(x86_pmu_event_addr(i)))
141                         goto perfctr_fail;
142         }
143
144         for (i = 0; i < x86_pmu.num_counters; i++) {
145                 if (!reserve_evntsel_nmi(x86_pmu_config_addr(i)))
146                         goto eventsel_fail;
147         }
148
149         return true;
150
151 eventsel_fail:
152         for (i--; i >= 0; i--)
153                 release_evntsel_nmi(x86_pmu_config_addr(i));
154
155         i = x86_pmu.num_counters;
156
157 perfctr_fail:
158         for (i--; i >= 0; i--)
159                 release_perfctr_nmi(x86_pmu_event_addr(i));
160
161         return false;
162 }
163
164 static void release_pmc_hardware(void)
165 {
166         int i;
167
168         for (i = 0; i < x86_pmu.num_counters; i++) {
169                 release_perfctr_nmi(x86_pmu_event_addr(i));
170                 release_evntsel_nmi(x86_pmu_config_addr(i));
171         }
172 }
173
174 #else
175
176 static bool reserve_pmc_hardware(void) { return true; }
177 static void release_pmc_hardware(void) {}
178
179 #endif
180
181 static bool check_hw_exists(void)
182 {
183         u64 val, val_fail, val_new= ~0;
184         int i, reg, reg_fail, ret = 0;
185         int bios_fail = 0;
186
187         /*
188          * Check to see if the BIOS enabled any of the counters, if so
189          * complain and bail.
190          */
191         for (i = 0; i < x86_pmu.num_counters; i++) {
192                 reg = x86_pmu_config_addr(i);
193                 ret = rdmsrl_safe(reg, &val);
194                 if (ret)
195                         goto msr_fail;
196                 if (val & ARCH_PERFMON_EVENTSEL_ENABLE) {
197                         bios_fail = 1;
198                         val_fail = val;
199                         reg_fail = reg;
200                 }
201         }
202
203         if (x86_pmu.num_counters_fixed) {
204                 reg = MSR_ARCH_PERFMON_FIXED_CTR_CTRL;
205                 ret = rdmsrl_safe(reg, &val);
206                 if (ret)
207                         goto msr_fail;
208                 for (i = 0; i < x86_pmu.num_counters_fixed; i++) {
209                         if (val & (0x03 << i*4)) {
210                                 bios_fail = 1;
211                                 val_fail = val;
212                                 reg_fail = reg;
213                         }
214                 }
215         }
216
217         /*
218          * Read the current value, change it and read it back to see if it
219          * matches, this is needed to detect certain hardware emulators
220          * (qemu/kvm) that don't trap on the MSR access and always return 0s.
221          */
222         reg = x86_pmu_event_addr(0);
223         if (rdmsrl_safe(reg, &val))
224                 goto msr_fail;
225         val ^= 0xffffUL;
226         ret = wrmsrl_safe(reg, val);
227         ret |= rdmsrl_safe(reg, &val_new);
228         if (ret || val != val_new)
229                 goto msr_fail;
230
231         /*
232          * We still allow the PMU driver to operate:
233          */
234         if (bios_fail) {
235                 printk(KERN_CONT "Broken BIOS detected, complain to your hardware vendor.\n");
236                 printk(KERN_ERR FW_BUG "the BIOS has corrupted hw-PMU resources (MSR %x is %Lx)\n", reg_fail, val_fail);
237         }
238
239         return true;
240
241 msr_fail:
242         printk(KERN_CONT "Broken PMU hardware detected, using software events only.\n");
243         printk(KERN_ERR "Failed to access perfctr msr (MSR %x is %Lx)\n", reg, val_new);
244
245         return false;
246 }
247
248 static void hw_perf_event_destroy(struct perf_event *event)
249 {
250         if (atomic_dec_and_mutex_lock(&active_events, &pmc_reserve_mutex)) {
251                 release_pmc_hardware();
252                 release_ds_buffers();
253                 mutex_unlock(&pmc_reserve_mutex);
254         }
255 }
256
257 static inline int x86_pmu_initialized(void)
258 {
259         return x86_pmu.handle_irq != NULL;
260 }
261
262 static inline int
263 set_ext_hw_attr(struct hw_perf_event *hwc, struct perf_event *event)
264 {
265         struct perf_event_attr *attr = &event->attr;
266         unsigned int cache_type, cache_op, cache_result;
267         u64 config, val;
268
269         config = attr->config;
270
271         cache_type = (config >>  0) & 0xff;
272         if (cache_type >= PERF_COUNT_HW_CACHE_MAX)
273                 return -EINVAL;
274
275         cache_op = (config >>  8) & 0xff;
276         if (cache_op >= PERF_COUNT_HW_CACHE_OP_MAX)
277                 return -EINVAL;
278
279         cache_result = (config >> 16) & 0xff;
280         if (cache_result >= PERF_COUNT_HW_CACHE_RESULT_MAX)
281                 return -EINVAL;
282
283         val = hw_cache_event_ids[cache_type][cache_op][cache_result];
284
285         if (val == 0)
286                 return -ENOENT;
287
288         if (val == -1)
289                 return -EINVAL;
290
291         hwc->config |= val;
292         attr->config1 = hw_cache_extra_regs[cache_type][cache_op][cache_result];
293         return x86_pmu_extra_regs(val, event);
294 }
295
296 int x86_setup_perfctr(struct perf_event *event)
297 {
298         struct perf_event_attr *attr = &event->attr;
299         struct hw_perf_event *hwc = &event->hw;
300         u64 config;
301
302         if (!is_sampling_event(event)) {
303                 hwc->sample_period = x86_pmu.max_period;
304                 hwc->last_period = hwc->sample_period;
305                 local64_set(&hwc->period_left, hwc->sample_period);
306         } else {
307                 /*
308                  * If we have a PMU initialized but no APIC
309                  * interrupts, we cannot sample hardware
310                  * events (user-space has to fall back and
311                  * sample via a hrtimer based software event):
312                  */
313                 if (!x86_pmu.apic)
314                         return -EOPNOTSUPP;
315         }
316
317         if (attr->type == PERF_TYPE_RAW)
318                 return x86_pmu_extra_regs(event->attr.config, event);
319
320         if (attr->type == PERF_TYPE_HW_CACHE)
321                 return set_ext_hw_attr(hwc, event);
322
323         if (attr->config >= x86_pmu.max_events)
324                 return -EINVAL;
325
326         /*
327          * The generic map:
328          */
329         config = x86_pmu.event_map(attr->config);
330
331         if (config == 0)
332                 return -ENOENT;
333
334         if (config == -1LL)
335                 return -EINVAL;
336
337         /*
338          * Branch tracing:
339          */
340         if (attr->config == PERF_COUNT_HW_BRANCH_INSTRUCTIONS &&
341             !attr->freq && hwc->sample_period == 1) {
342                 /* BTS is not supported by this architecture. */
343                 if (!x86_pmu.bts_active)
344                         return -EOPNOTSUPP;
345
346                 /* BTS is currently only allowed for user-mode. */
347                 if (!attr->exclude_kernel)
348                         return -EOPNOTSUPP;
349         }
350
351         hwc->config |= config;
352
353         return 0;
354 }
355
356 /*
357  * check that branch_sample_type is compatible with
358  * settings needed for precise_ip > 1 which implies
359  * using the LBR to capture ALL taken branches at the
360  * priv levels of the measurement
361  */
362 static inline int precise_br_compat(struct perf_event *event)
363 {
364         u64 m = event->attr.branch_sample_type;
365         u64 b = 0;
366
367         /* must capture all branches */
368         if (!(m & PERF_SAMPLE_BRANCH_ANY))
369                 return 0;
370
371         m &= PERF_SAMPLE_BRANCH_KERNEL | PERF_SAMPLE_BRANCH_USER;
372
373         if (!event->attr.exclude_user)
374                 b |= PERF_SAMPLE_BRANCH_USER;
375
376         if (!event->attr.exclude_kernel)
377                 b |= PERF_SAMPLE_BRANCH_KERNEL;
378
379         /*
380          * ignore PERF_SAMPLE_BRANCH_HV, not supported on x86
381          */
382
383         return m == b;
384 }
385
386 int x86_pmu_hw_config(struct perf_event *event)
387 {
388         if (event->attr.precise_ip) {
389                 int precise = 0;
390
391                 /* Support for constant skid */
392                 if (x86_pmu.pebs_active && !x86_pmu.pebs_broken) {
393                         precise++;
394
395                         /* Support for IP fixup */
396                         if (x86_pmu.lbr_nr)
397                                 precise++;
398                 }
399
400                 if (event->attr.precise_ip > precise)
401                         return -EOPNOTSUPP;
402                 /*
403                  * check that PEBS LBR correction does not conflict with
404                  * whatever the user is asking with attr->branch_sample_type
405                  */
406                 if (event->attr.precise_ip > 1 &&
407                     x86_pmu.intel_cap.pebs_format < 2) {
408                         u64 *br_type = &event->attr.branch_sample_type;
409
410                         if (has_branch_stack(event)) {
411                                 if (!precise_br_compat(event))
412                                         return -EOPNOTSUPP;
413
414                                 /* branch_sample_type is compatible */
415
416                         } else {
417                                 /*
418                                  * user did not specify  branch_sample_type
419                                  *
420                                  * For PEBS fixups, we capture all
421                                  * the branches at the priv level of the
422                                  * event.
423                                  */
424                                 *br_type = PERF_SAMPLE_BRANCH_ANY;
425
426                                 if (!event->attr.exclude_user)
427                                         *br_type |= PERF_SAMPLE_BRANCH_USER;
428
429                                 if (!event->attr.exclude_kernel)
430                                         *br_type |= PERF_SAMPLE_BRANCH_KERNEL;
431                         }
432                 }
433         }
434
435         /*
436          * Generate PMC IRQs:
437          * (keep 'enabled' bit clear for now)
438          */
439         event->hw.config = ARCH_PERFMON_EVENTSEL_INT;
440
441         /*
442          * Count user and OS events unless requested not to
443          */
444         if (!event->attr.exclude_user)
445                 event->hw.config |= ARCH_PERFMON_EVENTSEL_USR;
446         if (!event->attr.exclude_kernel)
447                 event->hw.config |= ARCH_PERFMON_EVENTSEL_OS;
448
449         if (event->attr.type == PERF_TYPE_RAW)
450                 event->hw.config |= event->attr.config & X86_RAW_EVENT_MASK;
451
452         return x86_setup_perfctr(event);
453 }
454
455 /*
456  * Setup the hardware configuration for a given attr_type
457  */
458 static int __x86_pmu_event_init(struct perf_event *event)
459 {
460         int err;
461
462         if (!x86_pmu_initialized())
463                 return -ENODEV;
464
465         err = 0;
466         if (!atomic_inc_not_zero(&active_events)) {
467                 mutex_lock(&pmc_reserve_mutex);
468                 if (atomic_read(&active_events) == 0) {
469                         if (!reserve_pmc_hardware())
470                                 err = -EBUSY;
471                         else
472                                 reserve_ds_buffers();
473                 }
474                 if (!err)
475                         atomic_inc(&active_events);
476                 mutex_unlock(&pmc_reserve_mutex);
477         }
478         if (err)
479                 return err;
480
481         event->destroy = hw_perf_event_destroy;
482
483         event->hw.idx = -1;
484         event->hw.last_cpu = -1;
485         event->hw.last_tag = ~0ULL;
486
487         /* mark unused */
488         event->hw.extra_reg.idx = EXTRA_REG_NONE;
489         event->hw.branch_reg.idx = EXTRA_REG_NONE;
490
491         return x86_pmu.hw_config(event);
492 }
493
494 void x86_pmu_disable_all(void)
495 {
496         struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events);
497         int idx;
498
499         for (idx = 0; idx < x86_pmu.num_counters; idx++) {
500                 u64 val;
501
502                 if (!test_bit(idx, cpuc->active_mask))
503                         continue;
504                 rdmsrl(x86_pmu_config_addr(idx), val);
505                 if (!(val & ARCH_PERFMON_EVENTSEL_ENABLE))
506                         continue;
507                 val &= ~ARCH_PERFMON_EVENTSEL_ENABLE;
508                 wrmsrl(x86_pmu_config_addr(idx), val);
509         }
510 }
511
512 static void x86_pmu_disable(struct pmu *pmu)
513 {
514         struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events);
515
516         if (!x86_pmu_initialized())
517                 return;
518
519         if (!cpuc->enabled)
520                 return;
521
522         cpuc->n_added = 0;
523         cpuc->enabled = 0;
524         barrier();
525
526         x86_pmu.disable_all();
527 }
528
529 void x86_pmu_enable_all(int added)
530 {
531         struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events);
532         int idx;
533
534         for (idx = 0; idx < x86_pmu.num_counters; idx++) {
535                 struct hw_perf_event *hwc = &cpuc->events[idx]->hw;
536
537                 if (!test_bit(idx, cpuc->active_mask))
538                         continue;
539
540                 __x86_pmu_enable_event(hwc, ARCH_PERFMON_EVENTSEL_ENABLE);
541         }
542 }
543
544 static struct pmu pmu;
545
546 static inline int is_x86_event(struct perf_event *event)
547 {
548         return event->pmu == &pmu;
549 }
550
551 /*
552  * Event scheduler state:
553  *
554  * Assign events iterating over all events and counters, beginning
555  * with events with least weights first. Keep the current iterator
556  * state in struct sched_state.
557  */
558 struct sched_state {
559         int     weight;
560         int     event;          /* event index */
561         int     counter;        /* counter index */
562         int     unassigned;     /* number of events to be assigned left */
563         unsigned long used[BITS_TO_LONGS(X86_PMC_IDX_MAX)];
564 };
565
566 /* Total max is X86_PMC_IDX_MAX, but we are O(n!) limited */
567 #define SCHED_STATES_MAX        2
568
569 struct perf_sched {
570         int                     max_weight;
571         int                     max_events;
572         struct perf_event       **events;
573         struct sched_state      state;
574         int                     saved_states;
575         struct sched_state      saved[SCHED_STATES_MAX];
576 };
577
578 /*
579  * Initialize interator that runs through all events and counters.
580  */
581 static void perf_sched_init(struct perf_sched *sched, struct perf_event **events,
582                             int num, int wmin, int wmax)
583 {
584         int idx;
585
586         memset(sched, 0, sizeof(*sched));
587         sched->max_events       = num;
588         sched->max_weight       = wmax;
589         sched->events           = events;
590
591         for (idx = 0; idx < num; idx++) {
592                 if (events[idx]->hw.constraint->weight == wmin)
593                         break;
594         }
595
596         sched->state.event      = idx;          /* start with min weight */
597         sched->state.weight     = wmin;
598         sched->state.unassigned = num;
599 }
600
601 static void perf_sched_save_state(struct perf_sched *sched)
602 {
603         if (WARN_ON_ONCE(sched->saved_states >= SCHED_STATES_MAX))
604                 return;
605
606         sched->saved[sched->saved_states] = sched->state;
607         sched->saved_states++;
608 }
609
610 static bool perf_sched_restore_state(struct perf_sched *sched)
611 {
612         if (!sched->saved_states)
613                 return false;
614
615         sched->saved_states--;
616         sched->state = sched->saved[sched->saved_states];
617
618         /* continue with next counter: */
619         clear_bit(sched->state.counter++, sched->state.used);
620
621         return true;
622 }
623
624 /*
625  * Select a counter for the current event to schedule. Return true on
626  * success.
627  */
628 static bool __perf_sched_find_counter(struct perf_sched *sched)
629 {
630         struct event_constraint *c;
631         int idx;
632
633         if (!sched->state.unassigned)
634                 return false;
635
636         if (sched->state.event >= sched->max_events)
637                 return false;
638
639         c = sched->events[sched->state.event]->hw.constraint;
640         /* Prefer fixed purpose counters */
641         if (c->idxmsk64 & (~0ULL << INTEL_PMC_IDX_FIXED)) {
642                 idx = INTEL_PMC_IDX_FIXED;
643                 for_each_set_bit_from(idx, c->idxmsk, X86_PMC_IDX_MAX) {
644                         if (!__test_and_set_bit(idx, sched->state.used))
645                                 goto done;
646                 }
647         }
648         /* Grab the first unused counter starting with idx */
649         idx = sched->state.counter;
650         for_each_set_bit_from(idx, c->idxmsk, INTEL_PMC_IDX_FIXED) {
651                 if (!__test_and_set_bit(idx, sched->state.used))
652                         goto done;
653         }
654
655         return false;
656
657 done:
658         sched->state.counter = idx;
659
660         if (c->overlap)
661                 perf_sched_save_state(sched);
662
663         return true;
664 }
665
666 static bool perf_sched_find_counter(struct perf_sched *sched)
667 {
668         while (!__perf_sched_find_counter(sched)) {
669                 if (!perf_sched_restore_state(sched))
670                         return false;
671         }
672
673         return true;
674 }
675
676 /*
677  * Go through all unassigned events and find the next one to schedule.
678  * Take events with the least weight first. Return true on success.
679  */
680 static bool perf_sched_next_event(struct perf_sched *sched)
681 {
682         struct event_constraint *c;
683
684         if (!sched->state.unassigned || !--sched->state.unassigned)
685                 return false;
686
687         do {
688                 /* next event */
689                 sched->state.event++;
690                 if (sched->state.event >= sched->max_events) {
691                         /* next weight */
692                         sched->state.event = 0;
693                         sched->state.weight++;
694                         if (sched->state.weight > sched->max_weight)
695                                 return false;
696                 }
697                 c = sched->events[sched->state.event]->hw.constraint;
698         } while (c->weight != sched->state.weight);
699
700         sched->state.counter = 0;       /* start with first counter */
701
702         return true;
703 }
704
705 /*
706  * Assign a counter for each event.
707  */
708 int perf_assign_events(struct perf_event **events, int n,
709                         int wmin, int wmax, int *assign)
710 {
711         struct perf_sched sched;
712
713         perf_sched_init(&sched, events, n, wmin, wmax);
714
715         do {
716                 if (!perf_sched_find_counter(&sched))
717                         break;  /* failed */
718                 if (assign)
719                         assign[sched.state.event] = sched.state.counter;
720         } while (perf_sched_next_event(&sched));
721
722         return sched.state.unassigned;
723 }
724
725 int x86_schedule_events(struct cpu_hw_events *cpuc, int n, int *assign)
726 {
727         struct event_constraint *c;
728         unsigned long used_mask[BITS_TO_LONGS(X86_PMC_IDX_MAX)];
729         struct perf_event *e;
730         int i, wmin, wmax, num = 0;
731         struct hw_perf_event *hwc;
732
733         bitmap_zero(used_mask, X86_PMC_IDX_MAX);
734
735         for (i = 0, wmin = X86_PMC_IDX_MAX, wmax = 0; i < n; i++) {
736                 hwc = &cpuc->event_list[i]->hw;
737                 c = x86_pmu.get_event_constraints(cpuc, cpuc->event_list[i]);
738                 hwc->constraint = c;
739
740                 wmin = min(wmin, c->weight);
741                 wmax = max(wmax, c->weight);
742         }
743
744         /*
745          * fastpath, try to reuse previous register
746          */
747         for (i = 0; i < n; i++) {
748                 hwc = &cpuc->event_list[i]->hw;
749                 c = hwc->constraint;
750
751                 /* never assigned */
752                 if (hwc->idx == -1)
753                         break;
754
755                 /* constraint still honored */
756                 if (!test_bit(hwc->idx, c->idxmsk))
757                         break;
758
759                 /* not already used */
760                 if (test_bit(hwc->idx, used_mask))
761                         break;
762
763                 __set_bit(hwc->idx, used_mask);
764                 if (assign)
765                         assign[i] = hwc->idx;
766         }
767
768         /* slow path */
769         if (i != n)
770                 num = perf_assign_events(cpuc->event_list, n, wmin,
771                                          wmax, assign);
772
773         /*
774          * Mark the event as committed, so we do not put_constraint()
775          * in case new events are added and fail scheduling.
776          */
777         if (!num && assign) {
778                 for (i = 0; i < n; i++) {
779                         e = cpuc->event_list[i];
780                         e->hw.flags |= PERF_X86_EVENT_COMMITTED;
781                 }
782         }
783         /*
784          * scheduling failed or is just a simulation,
785          * free resources if necessary
786          */
787         if (!assign || num) {
788                 for (i = 0; i < n; i++) {
789                         e = cpuc->event_list[i];
790                         /*
791                          * do not put_constraint() on comitted events,
792                          * because they are good to go
793                          */
794                         if ((e->hw.flags & PERF_X86_EVENT_COMMITTED))
795                                 continue;
796
797                         if (x86_pmu.put_event_constraints)
798                                 x86_pmu.put_event_constraints(cpuc, e);
799                 }
800         }
801         return num ? -EINVAL : 0;
802 }
803
804 /*
805  * dogrp: true if must collect siblings events (group)
806  * returns total number of events and error code
807  */
808 static int collect_events(struct cpu_hw_events *cpuc, struct perf_event *leader, bool dogrp)
809 {
810         struct perf_event *event;
811         int n, max_count;
812
813         max_count = x86_pmu.num_counters + x86_pmu.num_counters_fixed;
814
815         /* current number of events already accepted */
816         n = cpuc->n_events;
817
818         if (is_x86_event(leader)) {
819                 if (n >= max_count)
820                         return -EINVAL;
821                 cpuc->event_list[n] = leader;
822                 n++;
823         }
824         if (!dogrp)
825                 return n;
826
827         list_for_each_entry(event, &leader->sibling_list, group_entry) {
828                 if (!is_x86_event(event) ||
829                     event->state <= PERF_EVENT_STATE_OFF)
830                         continue;
831
832                 if (n >= max_count)
833                         return -EINVAL;
834
835                 cpuc->event_list[n] = event;
836                 n++;
837         }
838         return n;
839 }
840
841 static inline void x86_assign_hw_event(struct perf_event *event,
842                                 struct cpu_hw_events *cpuc, int i)
843 {
844         struct hw_perf_event *hwc = &event->hw;
845
846         hwc->idx = cpuc->assign[i];
847         hwc->last_cpu = smp_processor_id();
848         hwc->last_tag = ++cpuc->tags[i];
849
850         if (hwc->idx == INTEL_PMC_IDX_FIXED_BTS) {
851                 hwc->config_base = 0;
852                 hwc->event_base = 0;
853         } else if (hwc->idx >= INTEL_PMC_IDX_FIXED) {
854                 hwc->config_base = MSR_ARCH_PERFMON_FIXED_CTR_CTRL;
855                 hwc->event_base = MSR_ARCH_PERFMON_FIXED_CTR0 + (hwc->idx - INTEL_PMC_IDX_FIXED);
856                 hwc->event_base_rdpmc = (hwc->idx - INTEL_PMC_IDX_FIXED) | 1<<30;
857         } else {
858                 hwc->config_base = x86_pmu_config_addr(hwc->idx);
859                 hwc->event_base  = x86_pmu_event_addr(hwc->idx);
860                 hwc->event_base_rdpmc = x86_pmu_rdpmc_index(hwc->idx);
861         }
862 }
863
864 static inline int match_prev_assignment(struct hw_perf_event *hwc,
865                                         struct cpu_hw_events *cpuc,
866                                         int i)
867 {
868         return hwc->idx == cpuc->assign[i] &&
869                 hwc->last_cpu == smp_processor_id() &&
870                 hwc->last_tag == cpuc->tags[i];
871 }
872
873 static void x86_pmu_start(struct perf_event *event, int flags);
874
875 static void x86_pmu_enable(struct pmu *pmu)
876 {
877         struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events);
878         struct perf_event *event;
879         struct hw_perf_event *hwc;
880         int i, added = cpuc->n_added;
881
882         if (!x86_pmu_initialized())
883                 return;
884
885         if (cpuc->enabled)
886                 return;
887
888         if (cpuc->n_added) {
889                 int n_running = cpuc->n_events - cpuc->n_added;
890                 /*
891                  * apply assignment obtained either from
892                  * hw_perf_group_sched_in() or x86_pmu_enable()
893                  *
894                  * step1: save events moving to new counters
895                  * step2: reprogram moved events into new counters
896                  */
897                 for (i = 0; i < n_running; i++) {
898                         event = cpuc->event_list[i];
899                         hwc = &event->hw;
900
901                         /*
902                          * we can avoid reprogramming counter if:
903                          * - assigned same counter as last time
904                          * - running on same CPU as last time
905                          * - no other event has used the counter since
906                          */
907                         if (hwc->idx == -1 ||
908                             match_prev_assignment(hwc, cpuc, i))
909                                 continue;
910
911                         /*
912                          * Ensure we don't accidentally enable a stopped
913                          * counter simply because we rescheduled.
914                          */
915                         if (hwc->state & PERF_HES_STOPPED)
916                                 hwc->state |= PERF_HES_ARCH;
917
918                         x86_pmu_stop(event, PERF_EF_UPDATE);
919                 }
920
921                 for (i = 0; i < cpuc->n_events; i++) {
922                         event = cpuc->event_list[i];
923                         hwc = &event->hw;
924
925                         if (!match_prev_assignment(hwc, cpuc, i))
926                                 x86_assign_hw_event(event, cpuc, i);
927                         else if (i < n_running)
928                                 continue;
929
930                         if (hwc->state & PERF_HES_ARCH)
931                                 continue;
932
933                         x86_pmu_start(event, PERF_EF_RELOAD);
934                 }
935                 cpuc->n_added = 0;
936                 perf_events_lapic_init();
937         }
938
939         cpuc->enabled = 1;
940         barrier();
941
942         x86_pmu.enable_all(added);
943 }
944
945 static DEFINE_PER_CPU(u64 [X86_PMC_IDX_MAX], pmc_prev_left);
946
947 /*
948  * Set the next IRQ period, based on the hwc->period_left value.
949  * To be called with the event disabled in hw:
950  */
951 int x86_perf_event_set_period(struct perf_event *event)
952 {
953         struct hw_perf_event *hwc = &event->hw;
954         s64 left = local64_read(&hwc->period_left);
955         s64 period = hwc->sample_period;
956         int ret = 0, idx = hwc->idx;
957
958         if (idx == INTEL_PMC_IDX_FIXED_BTS)
959                 return 0;
960
961         /*
962          * If we are way outside a reasonable range then just skip forward:
963          */
964         if (unlikely(left <= -period)) {
965                 left = period;
966                 local64_set(&hwc->period_left, left);
967                 hwc->last_period = period;
968                 ret = 1;
969         }
970
971         if (unlikely(left <= 0)) {
972                 left += period;
973                 local64_set(&hwc->period_left, left);
974                 hwc->last_period = period;
975                 ret = 1;
976         }
977         /*
978          * Quirk: certain CPUs dont like it if just 1 hw_event is left:
979          */
980         if (unlikely(left < 2))
981                 left = 2;
982
983         if (left > x86_pmu.max_period)
984                 left = x86_pmu.max_period;
985
986         per_cpu(pmc_prev_left[idx], smp_processor_id()) = left;
987
988         /*
989          * The hw event starts counting from this event offset,
990          * mark it to be able to extra future deltas:
991          */
992         local64_set(&hwc->prev_count, (u64)-left);
993
994         wrmsrl(hwc->event_base, (u64)(-left) & x86_pmu.cntval_mask);
995
996         /*
997          * Due to erratum on certan cpu we need
998          * a second write to be sure the register
999          * is updated properly
1000          */
1001         if (x86_pmu.perfctr_second_write) {
1002                 wrmsrl(hwc->event_base,
1003                         (u64)(-left) & x86_pmu.cntval_mask);
1004         }
1005
1006         perf_event_update_userpage(event);
1007
1008         return ret;
1009 }
1010
1011 void x86_pmu_enable_event(struct perf_event *event)
1012 {
1013         if (__this_cpu_read(cpu_hw_events.enabled))
1014                 __x86_pmu_enable_event(&event->hw,
1015                                        ARCH_PERFMON_EVENTSEL_ENABLE);
1016 }
1017
1018 /*
1019  * Add a single event to the PMU.
1020  *
1021  * The event is added to the group of enabled events
1022  * but only if it can be scehduled with existing events.
1023  */
1024 static int x86_pmu_add(struct perf_event *event, int flags)
1025 {
1026         struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events);
1027         struct hw_perf_event *hwc;
1028         int assign[X86_PMC_IDX_MAX];
1029         int n, n0, ret;
1030
1031         hwc = &event->hw;
1032
1033         perf_pmu_disable(event->pmu);
1034         n0 = cpuc->n_events;
1035         ret = n = collect_events(cpuc, event, false);
1036         if (ret < 0)
1037                 goto out;
1038
1039         hwc->state = PERF_HES_UPTODATE | PERF_HES_STOPPED;
1040         if (!(flags & PERF_EF_START))
1041                 hwc->state |= PERF_HES_ARCH;
1042
1043         /*
1044          * If group events scheduling transaction was started,
1045          * skip the schedulability test here, it will be performed
1046          * at commit time (->commit_txn) as a whole
1047          */
1048         if (cpuc->group_flag & PERF_EVENT_TXN)
1049                 goto done_collect;
1050
1051         ret = x86_pmu.schedule_events(cpuc, n, assign);
1052         if (ret)
1053                 goto out;
1054         /*
1055          * copy new assignment, now we know it is possible
1056          * will be used by hw_perf_enable()
1057          */
1058         memcpy(cpuc->assign, assign, n*sizeof(int));
1059
1060 done_collect:
1061         cpuc->n_events = n;
1062         cpuc->n_added += n - n0;
1063         cpuc->n_txn += n - n0;
1064
1065         ret = 0;
1066 out:
1067         perf_pmu_enable(event->pmu);
1068         return ret;
1069 }
1070
1071 static void x86_pmu_start(struct perf_event *event, int flags)
1072 {
1073         struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events);
1074         int idx = event->hw.idx;
1075
1076         if (WARN_ON_ONCE(!(event->hw.state & PERF_HES_STOPPED)))
1077                 return;
1078
1079         if (WARN_ON_ONCE(idx == -1))
1080                 return;
1081
1082         if (flags & PERF_EF_RELOAD) {
1083                 WARN_ON_ONCE(!(event->hw.state & PERF_HES_UPTODATE));
1084                 x86_perf_event_set_period(event);
1085         }
1086
1087         event->hw.state = 0;
1088
1089         cpuc->events[idx] = event;
1090         __set_bit(idx, cpuc->active_mask);
1091         __set_bit(idx, cpuc->running);
1092         x86_pmu.enable(event);
1093         perf_event_update_userpage(event);
1094 }
1095
1096 void perf_event_print_debug(void)
1097 {
1098         u64 ctrl, status, overflow, pmc_ctrl, pmc_count, prev_left, fixed;
1099         u64 pebs;
1100         struct cpu_hw_events *cpuc;
1101         unsigned long flags;
1102         int cpu, idx;
1103
1104         if (!x86_pmu.num_counters)
1105                 return;
1106
1107         local_irq_save(flags);
1108
1109         cpu = smp_processor_id();
1110         cpuc = &per_cpu(cpu_hw_events, cpu);
1111
1112         if (x86_pmu.version >= 2) {
1113                 rdmsrl(MSR_CORE_PERF_GLOBAL_CTRL, ctrl);
1114                 rdmsrl(MSR_CORE_PERF_GLOBAL_STATUS, status);
1115                 rdmsrl(MSR_CORE_PERF_GLOBAL_OVF_CTRL, overflow);
1116                 rdmsrl(MSR_ARCH_PERFMON_FIXED_CTR_CTRL, fixed);
1117                 rdmsrl(MSR_IA32_PEBS_ENABLE, pebs);
1118
1119                 pr_info("\n");
1120                 pr_info("CPU#%d: ctrl:       %016llx\n", cpu, ctrl);
1121                 pr_info("CPU#%d: status:     %016llx\n", cpu, status);
1122                 pr_info("CPU#%d: overflow:   %016llx\n", cpu, overflow);
1123                 pr_info("CPU#%d: fixed:      %016llx\n", cpu, fixed);
1124                 pr_info("CPU#%d: pebs:       %016llx\n", cpu, pebs);
1125         }
1126         pr_info("CPU#%d: active:     %016llx\n", cpu, *(u64 *)cpuc->active_mask);
1127
1128         for (idx = 0; idx < x86_pmu.num_counters; idx++) {
1129                 rdmsrl(x86_pmu_config_addr(idx), pmc_ctrl);
1130                 rdmsrl(x86_pmu_event_addr(idx), pmc_count);
1131
1132                 prev_left = per_cpu(pmc_prev_left[idx], cpu);
1133
1134                 pr_info("CPU#%d:   gen-PMC%d ctrl:  %016llx\n",
1135                         cpu, idx, pmc_ctrl);
1136                 pr_info("CPU#%d:   gen-PMC%d count: %016llx\n",
1137                         cpu, idx, pmc_count);
1138                 pr_info("CPU#%d:   gen-PMC%d left:  %016llx\n",
1139                         cpu, idx, prev_left);
1140         }
1141         for (idx = 0; idx < x86_pmu.num_counters_fixed; idx++) {
1142                 rdmsrl(MSR_ARCH_PERFMON_FIXED_CTR0 + idx, pmc_count);
1143
1144                 pr_info("CPU#%d: fixed-PMC%d count: %016llx\n",
1145                         cpu, idx, pmc_count);
1146         }
1147         local_irq_restore(flags);
1148 }
1149
1150 void x86_pmu_stop(struct perf_event *event, int flags)
1151 {
1152         struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events);
1153         struct hw_perf_event *hwc = &event->hw;
1154
1155         if (__test_and_clear_bit(hwc->idx, cpuc->active_mask)) {
1156                 x86_pmu.disable(event);
1157                 cpuc->events[hwc->idx] = NULL;
1158                 WARN_ON_ONCE(hwc->state & PERF_HES_STOPPED);
1159                 hwc->state |= PERF_HES_STOPPED;
1160         }
1161
1162         if ((flags & PERF_EF_UPDATE) && !(hwc->state & PERF_HES_UPTODATE)) {
1163                 /*
1164                  * Drain the remaining delta count out of a event
1165                  * that we are disabling:
1166                  */
1167                 x86_perf_event_update(event);
1168                 hwc->state |= PERF_HES_UPTODATE;
1169         }
1170 }
1171
1172 static void x86_pmu_del(struct perf_event *event, int flags)
1173 {
1174         struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events);
1175         int i;
1176
1177         /*
1178          * event is descheduled
1179          */
1180         event->hw.flags &= ~PERF_X86_EVENT_COMMITTED;
1181
1182         /*
1183          * If we're called during a txn, we don't need to do anything.
1184          * The events never got scheduled and ->cancel_txn will truncate
1185          * the event_list.
1186          */
1187         if (cpuc->group_flag & PERF_EVENT_TXN)
1188                 return;
1189
1190         x86_pmu_stop(event, PERF_EF_UPDATE);
1191
1192         for (i = 0; i < cpuc->n_events; i++) {
1193                 if (event == cpuc->event_list[i]) {
1194
1195                         if (x86_pmu.put_event_constraints)
1196                                 x86_pmu.put_event_constraints(cpuc, event);
1197
1198                         while (++i < cpuc->n_events)
1199                                 cpuc->event_list[i-1] = cpuc->event_list[i];
1200
1201                         --cpuc->n_events;
1202                         break;
1203                 }
1204         }
1205         perf_event_update_userpage(event);
1206 }
1207
1208 int x86_pmu_handle_irq(struct pt_regs *regs)
1209 {
1210         struct perf_sample_data data;
1211         struct cpu_hw_events *cpuc;
1212         struct perf_event *event;
1213         int idx, handled = 0;
1214         u64 val;
1215
1216         cpuc = &__get_cpu_var(cpu_hw_events);
1217
1218         /*
1219          * Some chipsets need to unmask the LVTPC in a particular spot
1220          * inside the nmi handler.  As a result, the unmasking was pushed
1221          * into all the nmi handlers.
1222          *
1223          * This generic handler doesn't seem to have any issues where the
1224          * unmasking occurs so it was left at the top.
1225          */
1226         apic_write(APIC_LVTPC, APIC_DM_NMI);
1227
1228         for (idx = 0; idx < x86_pmu.num_counters; idx++) {
1229                 if (!test_bit(idx, cpuc->active_mask)) {
1230                         /*
1231                          * Though we deactivated the counter some cpus
1232                          * might still deliver spurious interrupts still
1233                          * in flight. Catch them:
1234                          */
1235                         if (__test_and_clear_bit(idx, cpuc->running))
1236                                 handled++;
1237                         continue;
1238                 }
1239
1240                 event = cpuc->events[idx];
1241
1242                 val = x86_perf_event_update(event);
1243                 if (val & (1ULL << (x86_pmu.cntval_bits - 1)))
1244                         continue;
1245
1246                 /*
1247                  * event overflow
1248                  */
1249                 handled++;
1250                 perf_sample_data_init(&data, 0, event->hw.last_period);
1251
1252                 if (!x86_perf_event_set_period(event))
1253                         continue;
1254
1255                 if (perf_event_overflow(event, &data, regs))
1256                         x86_pmu_stop(event, 0);
1257         }
1258
1259         if (handled)
1260                 inc_irq_stat(apic_perf_irqs);
1261
1262         return handled;
1263 }
1264
1265 void perf_events_lapic_init(void)
1266 {
1267         if (!x86_pmu.apic || !x86_pmu_initialized())
1268                 return;
1269
1270         /*
1271          * Always use NMI for PMU
1272          */
1273         apic_write(APIC_LVTPC, APIC_DM_NMI);
1274 }
1275
1276 static int __kprobes
1277 perf_event_nmi_handler(unsigned int cmd, struct pt_regs *regs)
1278 {
1279         u64 start_clock;
1280         u64 finish_clock;
1281         int ret;
1282
1283         if (!atomic_read(&active_events))
1284                 return NMI_DONE;
1285
1286         start_clock = sched_clock();
1287         ret = x86_pmu.handle_irq(regs);
1288         finish_clock = sched_clock();
1289
1290         perf_sample_event_took(finish_clock - start_clock);
1291
1292         return ret;
1293 }
1294
1295 struct event_constraint emptyconstraint;
1296 struct event_constraint unconstrained;
1297
1298 static int
1299 x86_pmu_notifier(struct notifier_block *self, unsigned long action, void *hcpu)
1300 {
1301         unsigned int cpu = (long)hcpu;
1302         struct cpu_hw_events *cpuc = &per_cpu(cpu_hw_events, cpu);
1303         int ret = NOTIFY_OK;
1304
1305         switch (action & ~CPU_TASKS_FROZEN) {
1306         case CPU_UP_PREPARE:
1307                 cpuc->kfree_on_online = NULL;
1308                 if (x86_pmu.cpu_prepare)
1309                         ret = x86_pmu.cpu_prepare(cpu);
1310                 break;
1311
1312         case CPU_STARTING:
1313                 if (x86_pmu.attr_rdpmc)
1314                         set_in_cr4(X86_CR4_PCE);
1315                 if (x86_pmu.cpu_starting)
1316                         x86_pmu.cpu_starting(cpu);
1317                 break;
1318
1319         case CPU_ONLINE:
1320                 kfree(cpuc->kfree_on_online);
1321                 break;
1322
1323         case CPU_DYING:
1324                 if (x86_pmu.cpu_dying)
1325                         x86_pmu.cpu_dying(cpu);
1326                 break;
1327
1328         case CPU_UP_CANCELED:
1329         case CPU_DEAD:
1330                 if (x86_pmu.cpu_dead)
1331                         x86_pmu.cpu_dead(cpu);
1332                 break;
1333
1334         default:
1335                 break;
1336         }
1337
1338         return ret;
1339 }
1340
1341 static void __init pmu_check_apic(void)
1342 {
1343         if (cpu_has_apic)
1344                 return;
1345
1346         x86_pmu.apic = 0;
1347         pr_info("no APIC, boot with the \"lapic\" boot parameter to force-enable it.\n");
1348         pr_info("no hardware sampling interrupt available.\n");
1349 }
1350
1351 static struct attribute_group x86_pmu_format_group = {
1352         .name = "format",
1353         .attrs = NULL,
1354 };
1355
1356 /*
1357  * Remove all undefined events (x86_pmu.event_map(id) == 0)
1358  * out of events_attr attributes.
1359  */
1360 static void __init filter_events(struct attribute **attrs)
1361 {
1362         struct device_attribute *d;
1363         struct perf_pmu_events_attr *pmu_attr;
1364         int i, j;
1365
1366         for (i = 0; attrs[i]; i++) {
1367                 d = (struct device_attribute *)attrs[i];
1368                 pmu_attr = container_of(d, struct perf_pmu_events_attr, attr);
1369                 /* str trumps id */
1370                 if (pmu_attr->event_str)
1371                         continue;
1372                 if (x86_pmu.event_map(i))
1373                         continue;
1374
1375                 for (j = i; attrs[j]; j++)
1376                         attrs[j] = attrs[j + 1];
1377
1378                 /* Check the shifted attr. */
1379                 i--;
1380         }
1381 }
1382
1383 /* Merge two pointer arrays */
1384 static __init struct attribute **merge_attr(struct attribute **a, struct attribute **b)
1385 {
1386         struct attribute **new;
1387         int j, i;
1388
1389         for (j = 0; a[j]; j++)
1390                 ;
1391         for (i = 0; b[i]; i++)
1392                 j++;
1393         j++;
1394
1395         new = kmalloc(sizeof(struct attribute *) * j, GFP_KERNEL);
1396         if (!new)
1397                 return NULL;
1398
1399         j = 0;
1400         for (i = 0; a[i]; i++)
1401                 new[j++] = a[i];
1402         for (i = 0; b[i]; i++)
1403                 new[j++] = b[i];
1404         new[j] = NULL;
1405
1406         return new;
1407 }
1408
1409 ssize_t events_sysfs_show(struct device *dev, struct device_attribute *attr,
1410                           char *page)
1411 {
1412         struct perf_pmu_events_attr *pmu_attr = \
1413                 container_of(attr, struct perf_pmu_events_attr, attr);
1414         u64 config = x86_pmu.event_map(pmu_attr->id);
1415
1416         /* string trumps id */
1417         if (pmu_attr->event_str)
1418                 return sprintf(page, "%s", pmu_attr->event_str);
1419
1420         return x86_pmu.events_sysfs_show(page, config);
1421 }
1422
1423 EVENT_ATTR(cpu-cycles,                  CPU_CYCLES              );
1424 EVENT_ATTR(instructions,                INSTRUCTIONS            );
1425 EVENT_ATTR(cache-references,            CACHE_REFERENCES        );
1426 EVENT_ATTR(cache-misses,                CACHE_MISSES            );
1427 EVENT_ATTR(branch-instructions,         BRANCH_INSTRUCTIONS     );
1428 EVENT_ATTR(branch-misses,               BRANCH_MISSES           );
1429 EVENT_ATTR(bus-cycles,                  BUS_CYCLES              );
1430 EVENT_ATTR(stalled-cycles-frontend,     STALLED_CYCLES_FRONTEND );
1431 EVENT_ATTR(stalled-cycles-backend,      STALLED_CYCLES_BACKEND  );
1432 EVENT_ATTR(ref-cycles,                  REF_CPU_CYCLES          );
1433
1434 static struct attribute *empty_attrs;
1435
1436 static struct attribute *events_attr[] = {
1437         EVENT_PTR(CPU_CYCLES),
1438         EVENT_PTR(INSTRUCTIONS),
1439         EVENT_PTR(CACHE_REFERENCES),
1440         EVENT_PTR(CACHE_MISSES),
1441         EVENT_PTR(BRANCH_INSTRUCTIONS),
1442         EVENT_PTR(BRANCH_MISSES),
1443         EVENT_PTR(BUS_CYCLES),
1444         EVENT_PTR(STALLED_CYCLES_FRONTEND),
1445         EVENT_PTR(STALLED_CYCLES_BACKEND),
1446         EVENT_PTR(REF_CPU_CYCLES),
1447         NULL,
1448 };
1449
1450 static struct attribute_group x86_pmu_events_group = {
1451         .name = "events",
1452         .attrs = events_attr,
1453 };
1454
1455 ssize_t x86_event_sysfs_show(char *page, u64 config, u64 event)
1456 {
1457         u64 umask  = (config & ARCH_PERFMON_EVENTSEL_UMASK) >> 8;
1458         u64 cmask  = (config & ARCH_PERFMON_EVENTSEL_CMASK) >> 24;
1459         bool edge  = (config & ARCH_PERFMON_EVENTSEL_EDGE);
1460         bool pc    = (config & ARCH_PERFMON_EVENTSEL_PIN_CONTROL);
1461         bool any   = (config & ARCH_PERFMON_EVENTSEL_ANY);
1462         bool inv   = (config & ARCH_PERFMON_EVENTSEL_INV);
1463         ssize_t ret;
1464
1465         /*
1466         * We have whole page size to spend and just little data
1467         * to write, so we can safely use sprintf.
1468         */
1469         ret = sprintf(page, "event=0x%02llx", event);
1470
1471         if (umask)
1472                 ret += sprintf(page + ret, ",umask=0x%02llx", umask);
1473
1474         if (edge)
1475                 ret += sprintf(page + ret, ",edge");
1476
1477         if (pc)
1478                 ret += sprintf(page + ret, ",pc");
1479
1480         if (any)
1481                 ret += sprintf(page + ret, ",any");
1482
1483         if (inv)
1484                 ret += sprintf(page + ret, ",inv");
1485
1486         if (cmask)
1487                 ret += sprintf(page + ret, ",cmask=0x%02llx", cmask);
1488
1489         ret += sprintf(page + ret, "\n");
1490
1491         return ret;
1492 }
1493
1494 static int __init init_hw_perf_events(void)
1495 {
1496         struct x86_pmu_quirk *quirk;
1497         int err;
1498
1499         pr_info("Performance Events: ");
1500
1501         switch (boot_cpu_data.x86_vendor) {
1502         case X86_VENDOR_INTEL:
1503                 err = intel_pmu_init();
1504                 break;
1505         case X86_VENDOR_AMD:
1506                 err = amd_pmu_init();
1507                 break;
1508         default:
1509                 err = -ENOTSUPP;
1510         }
1511         if (err != 0) {
1512                 pr_cont("no PMU driver, software events only.\n");
1513                 return 0;
1514         }
1515
1516         pmu_check_apic();
1517
1518         /* sanity check that the hardware exists or is emulated */
1519         if (!check_hw_exists())
1520                 return 0;
1521
1522         pr_cont("%s PMU driver.\n", x86_pmu.name);
1523
1524         for (quirk = x86_pmu.quirks; quirk; quirk = quirk->next)
1525                 quirk->func();
1526
1527         if (!x86_pmu.intel_ctrl)
1528                 x86_pmu.intel_ctrl = (1 << x86_pmu.num_counters) - 1;
1529
1530         perf_events_lapic_init();
1531         register_nmi_handler(NMI_LOCAL, perf_event_nmi_handler, 0, "PMI");
1532
1533         unconstrained = (struct event_constraint)
1534                 __EVENT_CONSTRAINT(0, (1ULL << x86_pmu.num_counters) - 1,
1535                                    0, x86_pmu.num_counters, 0, 0);
1536
1537         x86_pmu.attr_rdpmc = 1; /* enable userspace RDPMC usage by default */
1538         x86_pmu_format_group.attrs = x86_pmu.format_attrs;
1539
1540         if (x86_pmu.event_attrs)
1541                 x86_pmu_events_group.attrs = x86_pmu.event_attrs;
1542
1543         if (!x86_pmu.events_sysfs_show)
1544                 x86_pmu_events_group.attrs = &empty_attrs;
1545         else
1546                 filter_events(x86_pmu_events_group.attrs);
1547
1548         if (x86_pmu.cpu_events) {
1549                 struct attribute **tmp;
1550
1551                 tmp = merge_attr(x86_pmu_events_group.attrs, x86_pmu.cpu_events);
1552                 if (!WARN_ON(!tmp))
1553                         x86_pmu_events_group.attrs = tmp;
1554         }
1555
1556         pr_info("... version:                %d\n",     x86_pmu.version);
1557         pr_info("... bit width:              %d\n",     x86_pmu.cntval_bits);
1558         pr_info("... generic registers:      %d\n",     x86_pmu.num_counters);
1559         pr_info("... value mask:             %016Lx\n", x86_pmu.cntval_mask);
1560         pr_info("... max period:             %016Lx\n", x86_pmu.max_period);
1561         pr_info("... fixed-purpose events:   %d\n",     x86_pmu.num_counters_fixed);
1562         pr_info("... event mask:             %016Lx\n", x86_pmu.intel_ctrl);
1563
1564         perf_pmu_register(&pmu, "cpu", PERF_TYPE_RAW);
1565         perf_cpu_notifier(x86_pmu_notifier);
1566
1567         return 0;
1568 }
1569 early_initcall(init_hw_perf_events);
1570
1571 static inline void x86_pmu_read(struct perf_event *event)
1572 {
1573         x86_perf_event_update(event);
1574 }
1575
1576 /*
1577  * Start group events scheduling transaction
1578  * Set the flag to make pmu::enable() not perform the
1579  * schedulability test, it will be performed at commit time
1580  */
1581 static void x86_pmu_start_txn(struct pmu *pmu)
1582 {
1583         perf_pmu_disable(pmu);
1584         __this_cpu_or(cpu_hw_events.group_flag, PERF_EVENT_TXN);
1585         __this_cpu_write(cpu_hw_events.n_txn, 0);
1586 }
1587
1588 /*
1589  * Stop group events scheduling transaction
1590  * Clear the flag and pmu::enable() will perform the
1591  * schedulability test.
1592  */
1593 static void x86_pmu_cancel_txn(struct pmu *pmu)
1594 {
1595         __this_cpu_and(cpu_hw_events.group_flag, ~PERF_EVENT_TXN);
1596         /*
1597          * Truncate the collected events.
1598          */
1599         __this_cpu_sub(cpu_hw_events.n_added, __this_cpu_read(cpu_hw_events.n_txn));
1600         __this_cpu_sub(cpu_hw_events.n_events, __this_cpu_read(cpu_hw_events.n_txn));
1601         perf_pmu_enable(pmu);
1602 }
1603
1604 /*
1605  * Commit group events scheduling transaction
1606  * Perform the group schedulability test as a whole
1607  * Return 0 if success
1608  */
1609 static int x86_pmu_commit_txn(struct pmu *pmu)
1610 {
1611         struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events);
1612         int assign[X86_PMC_IDX_MAX];
1613         int n, ret;
1614
1615         n = cpuc->n_events;
1616
1617         if (!x86_pmu_initialized())
1618                 return -EAGAIN;
1619
1620         ret = x86_pmu.schedule_events(cpuc, n, assign);
1621         if (ret)
1622                 return ret;
1623
1624         /*
1625          * copy new assignment, now we know it is possible
1626          * will be used by hw_perf_enable()
1627          */
1628         memcpy(cpuc->assign, assign, n*sizeof(int));
1629
1630         cpuc->group_flag &= ~PERF_EVENT_TXN;
1631         perf_pmu_enable(pmu);
1632         return 0;
1633 }
1634 /*
1635  * a fake_cpuc is used to validate event groups. Due to
1636  * the extra reg logic, we need to also allocate a fake
1637  * per_core and per_cpu structure. Otherwise, group events
1638  * using extra reg may conflict without the kernel being
1639  * able to catch this when the last event gets added to
1640  * the group.
1641  */
1642 static void free_fake_cpuc(struct cpu_hw_events *cpuc)
1643 {
1644         kfree(cpuc->shared_regs);
1645         kfree(cpuc);
1646 }
1647
1648 static struct cpu_hw_events *allocate_fake_cpuc(void)
1649 {
1650         struct cpu_hw_events *cpuc;
1651         int cpu = raw_smp_processor_id();
1652
1653         cpuc = kzalloc(sizeof(*cpuc), GFP_KERNEL);
1654         if (!cpuc)
1655                 return ERR_PTR(-ENOMEM);
1656
1657         /* only needed, if we have extra_regs */
1658         if (x86_pmu.extra_regs) {
1659                 cpuc->shared_regs = allocate_shared_regs(cpu);
1660                 if (!cpuc->shared_regs)
1661                         goto error;
1662         }
1663         cpuc->is_fake = 1;
1664         return cpuc;
1665 error:
1666         free_fake_cpuc(cpuc);
1667         return ERR_PTR(-ENOMEM);
1668 }
1669
1670 /*
1671  * validate that we can schedule this event
1672  */
1673 static int validate_event(struct perf_event *event)
1674 {
1675         struct cpu_hw_events *fake_cpuc;
1676         struct event_constraint *c;
1677         int ret = 0;
1678
1679         fake_cpuc = allocate_fake_cpuc();
1680         if (IS_ERR(fake_cpuc))
1681                 return PTR_ERR(fake_cpuc);
1682
1683         c = x86_pmu.get_event_constraints(fake_cpuc, event);
1684
1685         if (!c || !c->weight)
1686                 ret = -EINVAL;
1687
1688         if (x86_pmu.put_event_constraints)
1689                 x86_pmu.put_event_constraints(fake_cpuc, event);
1690
1691         free_fake_cpuc(fake_cpuc);
1692
1693         return ret;
1694 }
1695
1696 /*
1697  * validate a single event group
1698  *
1699  * validation include:
1700  *      - check events are compatible which each other
1701  *      - events do not compete for the same counter
1702  *      - number of events <= number of counters
1703  *
1704  * validation ensures the group can be loaded onto the
1705  * PMU if it was the only group available.
1706  */
1707 static int validate_group(struct perf_event *event)
1708 {
1709         struct perf_event *leader = event->group_leader;
1710         struct cpu_hw_events *fake_cpuc;
1711         int ret = -EINVAL, n;
1712
1713         fake_cpuc = allocate_fake_cpuc();
1714         if (IS_ERR(fake_cpuc))
1715                 return PTR_ERR(fake_cpuc);
1716         /*
1717          * the event is not yet connected with its
1718          * siblings therefore we must first collect
1719          * existing siblings, then add the new event
1720          * before we can simulate the scheduling
1721          */
1722         n = collect_events(fake_cpuc, leader, true);
1723         if (n < 0)
1724                 goto out;
1725
1726         fake_cpuc->n_events = n;
1727         n = collect_events(fake_cpuc, event, false);
1728         if (n < 0)
1729                 goto out;
1730
1731         fake_cpuc->n_events = n;
1732
1733         ret = x86_pmu.schedule_events(fake_cpuc, n, NULL);
1734
1735 out:
1736         free_fake_cpuc(fake_cpuc);
1737         return ret;
1738 }
1739
1740 static int x86_pmu_event_init(struct perf_event *event)
1741 {
1742         struct pmu *tmp;
1743         int err;
1744
1745         switch (event->attr.type) {
1746         case PERF_TYPE_RAW:
1747         case PERF_TYPE_HARDWARE:
1748         case PERF_TYPE_HW_CACHE:
1749                 break;
1750
1751         default:
1752                 return -ENOENT;
1753         }
1754
1755         err = __x86_pmu_event_init(event);
1756         if (!err) {
1757                 /*
1758                  * we temporarily connect event to its pmu
1759                  * such that validate_group() can classify
1760                  * it as an x86 event using is_x86_event()
1761                  */
1762                 tmp = event->pmu;
1763                 event->pmu = &pmu;
1764
1765                 if (event->group_leader != event)
1766                         err = validate_group(event);
1767                 else
1768                         err = validate_event(event);
1769
1770                 event->pmu = tmp;
1771         }
1772         if (err) {
1773                 if (event->destroy)
1774                         event->destroy(event);
1775         }
1776
1777         return err;
1778 }
1779
1780 static int x86_pmu_event_idx(struct perf_event *event)
1781 {
1782         int idx = event->hw.idx;
1783
1784         if (!x86_pmu.attr_rdpmc)
1785                 return 0;
1786
1787         if (x86_pmu.num_counters_fixed && idx >= INTEL_PMC_IDX_FIXED) {
1788                 idx -= INTEL_PMC_IDX_FIXED;
1789                 idx |= 1 << 30;
1790         }
1791
1792         return idx + 1;
1793 }
1794
1795 static ssize_t get_attr_rdpmc(struct device *cdev,
1796                               struct device_attribute *attr,
1797                               char *buf)
1798 {
1799         return snprintf(buf, 40, "%d\n", x86_pmu.attr_rdpmc);
1800 }
1801
1802 static void change_rdpmc(void *info)
1803 {
1804         bool enable = !!(unsigned long)info;
1805
1806         if (enable)
1807                 set_in_cr4(X86_CR4_PCE);
1808         else
1809                 clear_in_cr4(X86_CR4_PCE);
1810 }
1811
1812 static ssize_t set_attr_rdpmc(struct device *cdev,
1813                               struct device_attribute *attr,
1814                               const char *buf, size_t count)
1815 {
1816         unsigned long val;
1817         ssize_t ret;
1818
1819         ret = kstrtoul(buf, 0, &val);
1820         if (ret)
1821                 return ret;
1822
1823         if (!!val != !!x86_pmu.attr_rdpmc) {
1824                 x86_pmu.attr_rdpmc = !!val;
1825                 smp_call_function(change_rdpmc, (void *)val, 1);
1826         }
1827
1828         return count;
1829 }
1830
1831 static DEVICE_ATTR(rdpmc, S_IRUSR | S_IWUSR, get_attr_rdpmc, set_attr_rdpmc);
1832
1833 static struct attribute *x86_pmu_attrs[] = {
1834         &dev_attr_rdpmc.attr,
1835         NULL,
1836 };
1837
1838 static struct attribute_group x86_pmu_attr_group = {
1839         .attrs = x86_pmu_attrs,
1840 };
1841
1842 static const struct attribute_group *x86_pmu_attr_groups[] = {
1843         &x86_pmu_attr_group,
1844         &x86_pmu_format_group,
1845         &x86_pmu_events_group,
1846         NULL,
1847 };
1848
1849 static void x86_pmu_flush_branch_stack(void)
1850 {
1851         if (x86_pmu.flush_branch_stack)
1852                 x86_pmu.flush_branch_stack();
1853 }
1854
1855 void perf_check_microcode(void)
1856 {
1857         if (x86_pmu.check_microcode)
1858                 x86_pmu.check_microcode();
1859 }
1860 EXPORT_SYMBOL_GPL(perf_check_microcode);
1861
1862 static struct pmu pmu = {
1863         .pmu_enable             = x86_pmu_enable,
1864         .pmu_disable            = x86_pmu_disable,
1865
1866         .attr_groups            = x86_pmu_attr_groups,
1867
1868         .event_init             = x86_pmu_event_init,
1869
1870         .add                    = x86_pmu_add,
1871         .del                    = x86_pmu_del,
1872         .start                  = x86_pmu_start,
1873         .stop                   = x86_pmu_stop,
1874         .read                   = x86_pmu_read,
1875
1876         .start_txn              = x86_pmu_start_txn,
1877         .cancel_txn             = x86_pmu_cancel_txn,
1878         .commit_txn             = x86_pmu_commit_txn,
1879
1880         .event_idx              = x86_pmu_event_idx,
1881         .flush_branch_stack     = x86_pmu_flush_branch_stack,
1882 };
1883
1884 void arch_perf_update_userpage(struct perf_event_mmap_page *userpg, u64 now)
1885 {
1886         struct cyc2ns_data *data;
1887
1888         userpg->cap_user_time = 0;
1889         userpg->cap_user_time_zero = 0;
1890         userpg->cap_user_rdpmc = x86_pmu.attr_rdpmc;
1891         userpg->pmc_width = x86_pmu.cntval_bits;
1892
1893         if (!sched_clock_stable())
1894                 return;
1895
1896         data = cyc2ns_read_begin();
1897
1898         userpg->cap_user_time = 1;
1899         userpg->time_mult = data->cyc2ns_mul;
1900         userpg->time_shift = data->cyc2ns_shift;
1901         userpg->time_offset = data->cyc2ns_offset - now;
1902
1903         userpg->cap_user_time_zero = 1;
1904         userpg->time_zero = data->cyc2ns_offset;
1905
1906         cyc2ns_read_end(data);
1907 }
1908
1909 /*
1910  * callchain support
1911  */
1912
1913 static int backtrace_stack(void *data, char *name)
1914 {
1915         return 0;
1916 }
1917
1918 static void backtrace_address(void *data, unsigned long addr, int reliable)
1919 {
1920         struct perf_callchain_entry *entry = data;
1921
1922         perf_callchain_store(entry, addr);
1923 }
1924
1925 static const struct stacktrace_ops backtrace_ops = {
1926         .stack                  = backtrace_stack,
1927         .address                = backtrace_address,
1928         .walk_stack             = print_context_stack_bp,
1929 };
1930
1931 void
1932 perf_callchain_kernel(struct perf_callchain_entry *entry, struct pt_regs *regs)
1933 {
1934         if (perf_guest_cbs && perf_guest_cbs->is_in_guest()) {
1935                 /* TODO: We don't support guest os callchain now */
1936                 return;
1937         }
1938
1939         perf_callchain_store(entry, regs->ip);
1940
1941         dump_trace(NULL, regs, NULL, 0, &backtrace_ops, entry);
1942 }
1943
1944 static inline int
1945 valid_user_frame(const void __user *fp, unsigned long size)
1946 {
1947         return (__range_not_ok(fp, size, TASK_SIZE) == 0);
1948 }
1949
1950 static unsigned long get_segment_base(unsigned int segment)
1951 {
1952         struct desc_struct *desc;
1953         int idx = segment >> 3;
1954
1955         if ((segment & SEGMENT_TI_MASK) == SEGMENT_LDT) {
1956                 if (idx > LDT_ENTRIES)
1957                         return 0;
1958
1959                 if (idx > current->active_mm->context.size)
1960                         return 0;
1961
1962                 desc = current->active_mm->context.ldt;
1963         } else {
1964                 if (idx > GDT_ENTRIES)
1965                         return 0;
1966
1967                 desc = __this_cpu_ptr(&gdt_page.gdt[0]);
1968         }
1969
1970         return get_desc_base(desc + idx);
1971 }
1972
1973 #ifdef CONFIG_COMPAT
1974
1975 #include <asm/compat.h>
1976
1977 static inline int
1978 perf_callchain_user32(struct pt_regs *regs, struct perf_callchain_entry *entry)
1979 {
1980         /* 32-bit process in 64-bit kernel. */
1981         unsigned long ss_base, cs_base;
1982         struct stack_frame_ia32 frame;
1983         const void __user *fp;
1984
1985         if (!test_thread_flag(TIF_IA32))
1986                 return 0;
1987
1988         cs_base = get_segment_base(regs->cs);
1989         ss_base = get_segment_base(regs->ss);
1990
1991         fp = compat_ptr(ss_base + regs->bp);
1992         while (entry->nr < PERF_MAX_STACK_DEPTH) {
1993                 unsigned long bytes;
1994                 frame.next_frame     = 0;
1995                 frame.return_address = 0;
1996
1997                 bytes = copy_from_user_nmi(&frame, fp, sizeof(frame));
1998                 if (bytes != 0)
1999                         break;
2000
2001                 if (!valid_user_frame(fp, sizeof(frame)))
2002                         break;
2003
2004                 perf_callchain_store(entry, cs_base + frame.return_address);
2005                 fp = compat_ptr(ss_base + frame.next_frame);
2006         }
2007         return 1;
2008 }
2009 #else
2010 static inline int
2011 perf_callchain_user32(struct pt_regs *regs, struct perf_callchain_entry *entry)
2012 {
2013     return 0;
2014 }
2015 #endif
2016
2017 void
2018 perf_callchain_user(struct perf_callchain_entry *entry, struct pt_regs *regs)
2019 {
2020         struct stack_frame frame;
2021         const void __user *fp;
2022
2023         if (perf_guest_cbs && perf_guest_cbs->is_in_guest()) {
2024                 /* TODO: We don't support guest os callchain now */
2025                 return;
2026         }
2027
2028         /*
2029          * We don't know what to do with VM86 stacks.. ignore them for now.
2030          */
2031         if (regs->flags & (X86_VM_MASK | PERF_EFLAGS_VM))
2032                 return;
2033
2034         fp = (void __user *)regs->bp;
2035
2036         perf_callchain_store(entry, regs->ip);
2037
2038         if (!current->mm)
2039                 return;
2040
2041         if (perf_callchain_user32(regs, entry))
2042                 return;
2043
2044         while (entry->nr < PERF_MAX_STACK_DEPTH) {
2045                 unsigned long bytes;
2046                 frame.next_frame             = NULL;
2047                 frame.return_address = 0;
2048
2049                 bytes = copy_from_user_nmi(&frame, fp, sizeof(frame));
2050                 if (bytes != 0)
2051                         break;
2052
2053                 if (!valid_user_frame(fp, sizeof(frame)))
2054                         break;
2055
2056                 perf_callchain_store(entry, frame.return_address);
2057                 fp = frame.next_frame;
2058         }
2059 }
2060
2061 /*
2062  * Deal with code segment offsets for the various execution modes:
2063  *
2064  *   VM86 - the good olde 16 bit days, where the linear address is
2065  *          20 bits and we use regs->ip + 0x10 * regs->cs.
2066  *
2067  *   IA32 - Where we need to look at GDT/LDT segment descriptor tables
2068  *          to figure out what the 32bit base address is.
2069  *
2070  *    X32 - has TIF_X32 set, but is running in x86_64
2071  *
2072  * X86_64 - CS,DS,SS,ES are all zero based.
2073  */
2074 static unsigned long code_segment_base(struct pt_regs *regs)
2075 {
2076         /*
2077          * If we are in VM86 mode, add the segment offset to convert to a
2078          * linear address.
2079          */
2080         if (regs->flags & X86_VM_MASK)
2081                 return 0x10 * regs->cs;
2082
2083         /*
2084          * For IA32 we look at the GDT/LDT segment base to convert the
2085          * effective IP to a linear address.
2086          */
2087 #ifdef CONFIG_X86_32
2088         if (user_mode(regs) && regs->cs != __USER_CS)
2089                 return get_segment_base(regs->cs);
2090 #else
2091         if (test_thread_flag(TIF_IA32)) {
2092                 if (user_mode(regs) && regs->cs != __USER32_CS)
2093                         return get_segment_base(regs->cs);
2094         }
2095 #endif
2096         return 0;
2097 }
2098
2099 unsigned long perf_instruction_pointer(struct pt_regs *regs)
2100 {
2101         if (perf_guest_cbs && perf_guest_cbs->is_in_guest())
2102                 return perf_guest_cbs->get_guest_ip();
2103
2104         return regs->ip + code_segment_base(regs);
2105 }
2106
2107 unsigned long perf_misc_flags(struct pt_regs *regs)
2108 {
2109         int misc = 0;
2110
2111         if (perf_guest_cbs && perf_guest_cbs->is_in_guest()) {
2112                 if (perf_guest_cbs->is_user_mode())
2113                         misc |= PERF_RECORD_MISC_GUEST_USER;
2114                 else
2115                         misc |= PERF_RECORD_MISC_GUEST_KERNEL;
2116         } else {
2117                 if (user_mode(regs))
2118                         misc |= PERF_RECORD_MISC_USER;
2119                 else
2120                         misc |= PERF_RECORD_MISC_KERNEL;
2121         }
2122
2123         if (regs->flags & PERF_EFLAGS_EXACT)
2124                 misc |= PERF_RECORD_MISC_EXACT_IP;
2125
2126         return misc;
2127 }
2128
2129 void perf_get_x86_pmu_capability(struct x86_pmu_capability *cap)
2130 {
2131         cap->version            = x86_pmu.version;
2132         cap->num_counters_gp    = x86_pmu.num_counters;
2133         cap->num_counters_fixed = x86_pmu.num_counters_fixed;
2134         cap->bit_width_gp       = x86_pmu.cntval_bits;
2135         cap->bit_width_fixed    = x86_pmu.cntval_bits;
2136         cap->events_mask        = (unsigned int)x86_pmu.events_maskl;
2137         cap->events_mask_len    = x86_pmu.events_mask_len;
2138 }
2139 EXPORT_SYMBOL_GPL(perf_get_x86_pmu_capability);