xref: /linux/arch/x86/events/intel/ds.c (revision dc853e26)
1 #include <linux/bitops.h>
2 #include <linux/types.h>
3 #include <linux/slab.h>
4 
5 #include <asm/perf_event.h>
6 #include <asm/insn.h>
7 
8 #include "../perf_event.h"
9 
10 /* The size of a BTS record in bytes: */
11 #define BTS_RECORD_SIZE		24
12 
13 #define BTS_BUFFER_SIZE		(PAGE_SIZE << 4)
14 #define PEBS_BUFFER_SIZE	(PAGE_SIZE << 4)
15 #define PEBS_FIXUP_SIZE		PAGE_SIZE
16 
17 /*
18  * pebs_record_32 for p4 and core not supported
19 
20 struct pebs_record_32 {
21 	u32 flags, ip;
22 	u32 ax, bc, cx, dx;
23 	u32 si, di, bp, sp;
24 };
25 
26  */
27 
28 union intel_x86_pebs_dse {
29 	u64 val;
30 	struct {
31 		unsigned int ld_dse:4;
32 		unsigned int ld_stlb_miss:1;
33 		unsigned int ld_locked:1;
34 		unsigned int ld_reserved:26;
35 	};
36 	struct {
37 		unsigned int st_l1d_hit:1;
38 		unsigned int st_reserved1:3;
39 		unsigned int st_stlb_miss:1;
40 		unsigned int st_locked:1;
41 		unsigned int st_reserved2:26;
42 	};
43 };
44 
45 
46 /*
47  * Map PEBS Load Latency Data Source encodings to generic
48  * memory data source information
49  */
50 #define P(a, b) PERF_MEM_S(a, b)
51 #define OP_LH (P(OP, LOAD) | P(LVL, HIT))
52 #define SNOOP_NONE_MISS (P(SNOOP, NONE) | P(SNOOP, MISS))
53 
54 /* Version for Sandy Bridge and later */
55 static u64 pebs_data_source[] = {
56 	P(OP, LOAD) | P(LVL, MISS) | P(LVL, L3) | P(SNOOP, NA),/* 0x00:ukn L3 */
57 	OP_LH | P(LVL, L1)  | P(SNOOP, NONE),	/* 0x01: L1 local */
58 	OP_LH | P(LVL, LFB) | P(SNOOP, NONE),	/* 0x02: LFB hit */
59 	OP_LH | P(LVL, L2)  | P(SNOOP, NONE),	/* 0x03: L2 hit */
60 	OP_LH | P(LVL, L3)  | P(SNOOP, NONE),	/* 0x04: L3 hit */
61 	OP_LH | P(LVL, L3)  | P(SNOOP, MISS),	/* 0x05: L3 hit, snoop miss */
62 	OP_LH | P(LVL, L3)  | P(SNOOP, HIT),	/* 0x06: L3 hit, snoop hit */
63 	OP_LH | P(LVL, L3)  | P(SNOOP, HITM),	/* 0x07: L3 hit, snoop hitm */
64 	OP_LH | P(LVL, REM_CCE1) | P(SNOOP, HIT),  /* 0x08: L3 miss snoop hit */
65 	OP_LH | P(LVL, REM_CCE1) | P(SNOOP, HITM), /* 0x09: L3 miss snoop hitm*/
66 	OP_LH | P(LVL, LOC_RAM)  | P(SNOOP, HIT),  /* 0x0a: L3 miss, shared */
67 	OP_LH | P(LVL, REM_RAM1) | P(SNOOP, HIT),  /* 0x0b: L3 miss, shared */
68 	OP_LH | P(LVL, LOC_RAM)  | SNOOP_NONE_MISS,/* 0x0c: L3 miss, excl */
69 	OP_LH | P(LVL, REM_RAM1) | SNOOP_NONE_MISS,/* 0x0d: L3 miss, excl */
70 	OP_LH | P(LVL, IO)  | P(SNOOP, NONE), /* 0x0e: I/O */
71 	OP_LH | P(LVL, UNC) | P(SNOOP, NONE), /* 0x0f: uncached */
72 };
73 
74 /* Patch up minor differences in the bits */
75 void __init intel_pmu_pebs_data_source_nhm(void)
76 {
77 	pebs_data_source[0x05] = OP_LH | P(LVL, L3)  | P(SNOOP, HIT);
78 	pebs_data_source[0x06] = OP_LH | P(LVL, L3)  | P(SNOOP, HITM);
79 	pebs_data_source[0x07] = OP_LH | P(LVL, L3)  | P(SNOOP, HITM);
80 }
81 
82 static u64 precise_store_data(u64 status)
83 {
84 	union intel_x86_pebs_dse dse;
85 	u64 val = P(OP, STORE) | P(SNOOP, NA) | P(LVL, L1) | P(TLB, L2);
86 
87 	dse.val = status;
88 
89 	/*
90 	 * bit 4: TLB access
91 	 * 1 = stored missed 2nd level TLB
92 	 *
93 	 * so it either hit the walker or the OS
94 	 * otherwise hit 2nd level TLB
95 	 */
96 	if (dse.st_stlb_miss)
97 		val |= P(TLB, MISS);
98 	else
99 		val |= P(TLB, HIT);
100 
101 	/*
102 	 * bit 0: hit L1 data cache
103 	 * if not set, then all we know is that
104 	 * it missed L1D
105 	 */
106 	if (dse.st_l1d_hit)
107 		val |= P(LVL, HIT);
108 	else
109 		val |= P(LVL, MISS);
110 
111 	/*
112 	 * bit 5: Locked prefix
113 	 */
114 	if (dse.st_locked)
115 		val |= P(LOCK, LOCKED);
116 
117 	return val;
118 }
119 
120 static u64 precise_datala_hsw(struct perf_event *event, u64 status)
121 {
122 	union perf_mem_data_src dse;
123 
124 	dse.val = PERF_MEM_NA;
125 
126 	if (event->hw.flags & PERF_X86_EVENT_PEBS_ST_HSW)
127 		dse.mem_op = PERF_MEM_OP_STORE;
128 	else if (event->hw.flags & PERF_X86_EVENT_PEBS_LD_HSW)
129 		dse.mem_op = PERF_MEM_OP_LOAD;
130 
131 	/*
132 	 * L1 info only valid for following events:
133 	 *
134 	 * MEM_UOPS_RETIRED.STLB_MISS_STORES
135 	 * MEM_UOPS_RETIRED.LOCK_STORES
136 	 * MEM_UOPS_RETIRED.SPLIT_STORES
137 	 * MEM_UOPS_RETIRED.ALL_STORES
138 	 */
139 	if (event->hw.flags & PERF_X86_EVENT_PEBS_ST_HSW) {
140 		if (status & 1)
141 			dse.mem_lvl = PERF_MEM_LVL_L1 | PERF_MEM_LVL_HIT;
142 		else
143 			dse.mem_lvl = PERF_MEM_LVL_L1 | PERF_MEM_LVL_MISS;
144 	}
145 	return dse.val;
146 }
147 
148 static u64 load_latency_data(u64 status)
149 {
150 	union intel_x86_pebs_dse dse;
151 	u64 val;
152 	int model = boot_cpu_data.x86_model;
153 	int fam = boot_cpu_data.x86;
154 
155 	dse.val = status;
156 
157 	/*
158 	 * use the mapping table for bit 0-3
159 	 */
160 	val = pebs_data_source[dse.ld_dse];
161 
162 	/*
163 	 * Nehalem models do not support TLB, Lock infos
164 	 */
165 	if (fam == 0x6 && (model == 26 || model == 30
166 	    || model == 31 || model == 46)) {
167 		val |= P(TLB, NA) | P(LOCK, NA);
168 		return val;
169 	}
170 	/*
171 	 * bit 4: TLB access
172 	 * 0 = did not miss 2nd level TLB
173 	 * 1 = missed 2nd level TLB
174 	 */
175 	if (dse.ld_stlb_miss)
176 		val |= P(TLB, MISS) | P(TLB, L2);
177 	else
178 		val |= P(TLB, HIT) | P(TLB, L1) | P(TLB, L2);
179 
180 	/*
181 	 * bit 5: locked prefix
182 	 */
183 	if (dse.ld_locked)
184 		val |= P(LOCK, LOCKED);
185 
186 	return val;
187 }
188 
189 struct pebs_record_core {
190 	u64 flags, ip;
191 	u64 ax, bx, cx, dx;
192 	u64 si, di, bp, sp;
193 	u64 r8,  r9,  r10, r11;
194 	u64 r12, r13, r14, r15;
195 };
196 
197 struct pebs_record_nhm {
198 	u64 flags, ip;
199 	u64 ax, bx, cx, dx;
200 	u64 si, di, bp, sp;
201 	u64 r8,  r9,  r10, r11;
202 	u64 r12, r13, r14, r15;
203 	u64 status, dla, dse, lat;
204 };
205 
206 /*
207  * Same as pebs_record_nhm, with two additional fields.
208  */
209 struct pebs_record_hsw {
210 	u64 flags, ip;
211 	u64 ax, bx, cx, dx;
212 	u64 si, di, bp, sp;
213 	u64 r8,  r9,  r10, r11;
214 	u64 r12, r13, r14, r15;
215 	u64 status, dla, dse, lat;
216 	u64 real_ip, tsx_tuning;
217 };
218 
219 union hsw_tsx_tuning {
220 	struct {
221 		u32 cycles_last_block     : 32,
222 		    hle_abort		  : 1,
223 		    rtm_abort		  : 1,
224 		    instruction_abort     : 1,
225 		    non_instruction_abort : 1,
226 		    retry		  : 1,
227 		    data_conflict	  : 1,
228 		    capacity_writes	  : 1,
229 		    capacity_reads	  : 1;
230 	};
231 	u64	    value;
232 };
233 
234 #define PEBS_HSW_TSX_FLAGS	0xff00000000ULL
235 
236 /* Same as HSW, plus TSC */
237 
238 struct pebs_record_skl {
239 	u64 flags, ip;
240 	u64 ax, bx, cx, dx;
241 	u64 si, di, bp, sp;
242 	u64 r8,  r9,  r10, r11;
243 	u64 r12, r13, r14, r15;
244 	u64 status, dla, dse, lat;
245 	u64 real_ip, tsx_tuning;
246 	u64 tsc;
247 };
248 
249 void init_debug_store_on_cpu(int cpu)
250 {
251 	struct debug_store *ds = per_cpu(cpu_hw_events, cpu).ds;
252 
253 	if (!ds)
254 		return;
255 
256 	wrmsr_on_cpu(cpu, MSR_IA32_DS_AREA,
257 		     (u32)((u64)(unsigned long)ds),
258 		     (u32)((u64)(unsigned long)ds >> 32));
259 }
260 
261 void fini_debug_store_on_cpu(int cpu)
262 {
263 	if (!per_cpu(cpu_hw_events, cpu).ds)
264 		return;
265 
266 	wrmsr_on_cpu(cpu, MSR_IA32_DS_AREA, 0, 0);
267 }
268 
269 static DEFINE_PER_CPU(void *, insn_buffer);
270 
271 static int alloc_pebs_buffer(int cpu)
272 {
273 	struct debug_store *ds = per_cpu(cpu_hw_events, cpu).ds;
274 	int node = cpu_to_node(cpu);
275 	int max;
276 	void *buffer, *ibuffer;
277 
278 	if (!x86_pmu.pebs)
279 		return 0;
280 
281 	buffer = kzalloc_node(x86_pmu.pebs_buffer_size, GFP_KERNEL, node);
282 	if (unlikely(!buffer))
283 		return -ENOMEM;
284 
285 	/*
286 	 * HSW+ already provides us the eventing ip; no need to allocate this
287 	 * buffer then.
288 	 */
289 	if (x86_pmu.intel_cap.pebs_format < 2) {
290 		ibuffer = kzalloc_node(PEBS_FIXUP_SIZE, GFP_KERNEL, node);
291 		if (!ibuffer) {
292 			kfree(buffer);
293 			return -ENOMEM;
294 		}
295 		per_cpu(insn_buffer, cpu) = ibuffer;
296 	}
297 
298 	max = x86_pmu.pebs_buffer_size / x86_pmu.pebs_record_size;
299 
300 	ds->pebs_buffer_base = (u64)(unsigned long)buffer;
301 	ds->pebs_index = ds->pebs_buffer_base;
302 	ds->pebs_absolute_maximum = ds->pebs_buffer_base +
303 		max * x86_pmu.pebs_record_size;
304 
305 	return 0;
306 }
307 
308 static void release_pebs_buffer(int cpu)
309 {
310 	struct debug_store *ds = per_cpu(cpu_hw_events, cpu).ds;
311 
312 	if (!ds || !x86_pmu.pebs)
313 		return;
314 
315 	kfree(per_cpu(insn_buffer, cpu));
316 	per_cpu(insn_buffer, cpu) = NULL;
317 
318 	kfree((void *)(unsigned long)ds->pebs_buffer_base);
319 	ds->pebs_buffer_base = 0;
320 }
321 
322 static int alloc_bts_buffer(int cpu)
323 {
324 	struct debug_store *ds = per_cpu(cpu_hw_events, cpu).ds;
325 	int node = cpu_to_node(cpu);
326 	int max, thresh;
327 	void *buffer;
328 
329 	if (!x86_pmu.bts)
330 		return 0;
331 
332 	buffer = kzalloc_node(BTS_BUFFER_SIZE, GFP_KERNEL | __GFP_NOWARN, node);
333 	if (unlikely(!buffer)) {
334 		WARN_ONCE(1, "%s: BTS buffer allocation failure\n", __func__);
335 		return -ENOMEM;
336 	}
337 
338 	max = BTS_BUFFER_SIZE / BTS_RECORD_SIZE;
339 	thresh = max / 16;
340 
341 	ds->bts_buffer_base = (u64)(unsigned long)buffer;
342 	ds->bts_index = ds->bts_buffer_base;
343 	ds->bts_absolute_maximum = ds->bts_buffer_base +
344 		max * BTS_RECORD_SIZE;
345 	ds->bts_interrupt_threshold = ds->bts_absolute_maximum -
346 		thresh * BTS_RECORD_SIZE;
347 
348 	return 0;
349 }
350 
351 static void release_bts_buffer(int cpu)
352 {
353 	struct debug_store *ds = per_cpu(cpu_hw_events, cpu).ds;
354 
355 	if (!ds || !x86_pmu.bts)
356 		return;
357 
358 	kfree((void *)(unsigned long)ds->bts_buffer_base);
359 	ds->bts_buffer_base = 0;
360 }
361 
362 static int alloc_ds_buffer(int cpu)
363 {
364 	int node = cpu_to_node(cpu);
365 	struct debug_store *ds;
366 
367 	ds = kzalloc_node(sizeof(*ds), GFP_KERNEL, node);
368 	if (unlikely(!ds))
369 		return -ENOMEM;
370 
371 	per_cpu(cpu_hw_events, cpu).ds = ds;
372 
373 	return 0;
374 }
375 
376 static void release_ds_buffer(int cpu)
377 {
378 	struct debug_store *ds = per_cpu(cpu_hw_events, cpu).ds;
379 
380 	if (!ds)
381 		return;
382 
383 	per_cpu(cpu_hw_events, cpu).ds = NULL;
384 	kfree(ds);
385 }
386 
387 void release_ds_buffers(void)
388 {
389 	int cpu;
390 
391 	if (!x86_pmu.bts && !x86_pmu.pebs)
392 		return;
393 
394 	get_online_cpus();
395 	for_each_online_cpu(cpu)
396 		fini_debug_store_on_cpu(cpu);
397 
398 	for_each_possible_cpu(cpu) {
399 		release_pebs_buffer(cpu);
400 		release_bts_buffer(cpu);
401 		release_ds_buffer(cpu);
402 	}
403 	put_online_cpus();
404 }
405 
406 void reserve_ds_buffers(void)
407 {
408 	int bts_err = 0, pebs_err = 0;
409 	int cpu;
410 
411 	x86_pmu.bts_active = 0;
412 	x86_pmu.pebs_active = 0;
413 
414 	if (!x86_pmu.bts && !x86_pmu.pebs)
415 		return;
416 
417 	if (!x86_pmu.bts)
418 		bts_err = 1;
419 
420 	if (!x86_pmu.pebs)
421 		pebs_err = 1;
422 
423 	get_online_cpus();
424 
425 	for_each_possible_cpu(cpu) {
426 		if (alloc_ds_buffer(cpu)) {
427 			bts_err = 1;
428 			pebs_err = 1;
429 		}
430 
431 		if (!bts_err && alloc_bts_buffer(cpu))
432 			bts_err = 1;
433 
434 		if (!pebs_err && alloc_pebs_buffer(cpu))
435 			pebs_err = 1;
436 
437 		if (bts_err && pebs_err)
438 			break;
439 	}
440 
441 	if (bts_err) {
442 		for_each_possible_cpu(cpu)
443 			release_bts_buffer(cpu);
444 	}
445 
446 	if (pebs_err) {
447 		for_each_possible_cpu(cpu)
448 			release_pebs_buffer(cpu);
449 	}
450 
451 	if (bts_err && pebs_err) {
452 		for_each_possible_cpu(cpu)
453 			release_ds_buffer(cpu);
454 	} else {
455 		if (x86_pmu.bts && !bts_err)
456 			x86_pmu.bts_active = 1;
457 
458 		if (x86_pmu.pebs && !pebs_err)
459 			x86_pmu.pebs_active = 1;
460 
461 		for_each_online_cpu(cpu)
462 			init_debug_store_on_cpu(cpu);
463 	}
464 
465 	put_online_cpus();
466 }
467 
468 /*
469  * BTS
470  */
471 
472 struct event_constraint bts_constraint =
473 	EVENT_CONSTRAINT(0, 1ULL << INTEL_PMC_IDX_FIXED_BTS, 0);
474 
475 void intel_pmu_enable_bts(u64 config)
476 {
477 	unsigned long debugctlmsr;
478 
479 	debugctlmsr = get_debugctlmsr();
480 
481 	debugctlmsr |= DEBUGCTLMSR_TR;
482 	debugctlmsr |= DEBUGCTLMSR_BTS;
483 	if (config & ARCH_PERFMON_EVENTSEL_INT)
484 		debugctlmsr |= DEBUGCTLMSR_BTINT;
485 
486 	if (!(config & ARCH_PERFMON_EVENTSEL_OS))
487 		debugctlmsr |= DEBUGCTLMSR_BTS_OFF_OS;
488 
489 	if (!(config & ARCH_PERFMON_EVENTSEL_USR))
490 		debugctlmsr |= DEBUGCTLMSR_BTS_OFF_USR;
491 
492 	update_debugctlmsr(debugctlmsr);
493 }
494 
495 void intel_pmu_disable_bts(void)
496 {
497 	struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events);
498 	unsigned long debugctlmsr;
499 
500 	if (!cpuc->ds)
501 		return;
502 
503 	debugctlmsr = get_debugctlmsr();
504 
505 	debugctlmsr &=
506 		~(DEBUGCTLMSR_TR | DEBUGCTLMSR_BTS | DEBUGCTLMSR_BTINT |
507 		  DEBUGCTLMSR_BTS_OFF_OS | DEBUGCTLMSR_BTS_OFF_USR);
508 
509 	update_debugctlmsr(debugctlmsr);
510 }
511 
512 int intel_pmu_drain_bts_buffer(void)
513 {
514 	struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events);
515 	struct debug_store *ds = cpuc->ds;
516 	struct bts_record {
517 		u64	from;
518 		u64	to;
519 		u64	flags;
520 	};
521 	struct perf_event *event = cpuc->events[INTEL_PMC_IDX_FIXED_BTS];
522 	struct bts_record *at, *base, *top;
523 	struct perf_output_handle handle;
524 	struct perf_event_header header;
525 	struct perf_sample_data data;
526 	unsigned long skip = 0;
527 	struct pt_regs regs;
528 
529 	if (!event)
530 		return 0;
531 
532 	if (!x86_pmu.bts_active)
533 		return 0;
534 
535 	base = (struct bts_record *)(unsigned long)ds->bts_buffer_base;
536 	top  = (struct bts_record *)(unsigned long)ds->bts_index;
537 
538 	if (top <= base)
539 		return 0;
540 
541 	memset(&regs, 0, sizeof(regs));
542 
543 	ds->bts_index = ds->bts_buffer_base;
544 
545 	perf_sample_data_init(&data, 0, event->hw.last_period);
546 
547 	/*
548 	 * BTS leaks kernel addresses in branches across the cpl boundary,
549 	 * such as traps or system calls, so unless the user is asking for
550 	 * kernel tracing (and right now it's not possible), we'd need to
551 	 * filter them out. But first we need to count how many of those we
552 	 * have in the current batch. This is an extra O(n) pass, however,
553 	 * it's much faster than the other one especially considering that
554 	 * n <= 2560 (BTS_BUFFER_SIZE / BTS_RECORD_SIZE * 15/16; see the
555 	 * alloc_bts_buffer()).
556 	 */
557 	for (at = base; at < top; at++) {
558 		/*
559 		 * Note that right now *this* BTS code only works if
560 		 * attr::exclude_kernel is set, but let's keep this extra
561 		 * check here in case that changes.
562 		 */
563 		if (event->attr.exclude_kernel &&
564 		    (kernel_ip(at->from) || kernel_ip(at->to)))
565 			skip++;
566 	}
567 
568 	/*
569 	 * Prepare a generic sample, i.e. fill in the invariant fields.
570 	 * We will overwrite the from and to address before we output
571 	 * the sample.
572 	 */
573 	rcu_read_lock();
574 	perf_prepare_sample(&header, &data, event, &regs);
575 
576 	if (perf_output_begin(&handle, event, header.size *
577 			      (top - base - skip)))
578 		goto unlock;
579 
580 	for (at = base; at < top; at++) {
581 		/* Filter out any records that contain kernel addresses. */
582 		if (event->attr.exclude_kernel &&
583 		    (kernel_ip(at->from) || kernel_ip(at->to)))
584 			continue;
585 
586 		data.ip		= at->from;
587 		data.addr	= at->to;
588 
589 		perf_output_sample(&handle, &header, &data, event);
590 	}
591 
592 	perf_output_end(&handle);
593 
594 	/* There's new data available. */
595 	event->hw.interrupts++;
596 	event->pending_kill = POLL_IN;
597 unlock:
598 	rcu_read_unlock();
599 	return 1;
600 }
601 
602 static inline void intel_pmu_drain_pebs_buffer(void)
603 {
604 	struct pt_regs regs;
605 
606 	x86_pmu.drain_pebs(&regs);
607 }
608 
609 void intel_pmu_pebs_sched_task(struct perf_event_context *ctx, bool sched_in)
610 {
611 	if (!sched_in)
612 		intel_pmu_drain_pebs_buffer();
613 }
614 
615 /*
616  * PEBS
617  */
618 struct event_constraint intel_core2_pebs_event_constraints[] = {
619 	INTEL_FLAGS_UEVENT_CONSTRAINT(0x00c0, 0x1), /* INST_RETIRED.ANY */
620 	INTEL_FLAGS_UEVENT_CONSTRAINT(0xfec1, 0x1), /* X87_OPS_RETIRED.ANY */
621 	INTEL_FLAGS_UEVENT_CONSTRAINT(0x00c5, 0x1), /* BR_INST_RETIRED.MISPRED */
622 	INTEL_FLAGS_UEVENT_CONSTRAINT(0x1fc7, 0x1), /* SIMD_INST_RETURED.ANY */
623 	INTEL_FLAGS_EVENT_CONSTRAINT(0xcb, 0x1),    /* MEM_LOAD_RETIRED.* */
624 	/* INST_RETIRED.ANY_P, inv=1, cmask=16 (cycles:p). */
625 	INTEL_FLAGS_EVENT_CONSTRAINT(0x108000c0, 0x01),
626 	EVENT_CONSTRAINT_END
627 };
628 
629 struct event_constraint intel_atom_pebs_event_constraints[] = {
630 	INTEL_FLAGS_UEVENT_CONSTRAINT(0x00c0, 0x1), /* INST_RETIRED.ANY */
631 	INTEL_FLAGS_UEVENT_CONSTRAINT(0x00c5, 0x1), /* MISPREDICTED_BRANCH_RETIRED */
632 	INTEL_FLAGS_EVENT_CONSTRAINT(0xcb, 0x1),    /* MEM_LOAD_RETIRED.* */
633 	/* INST_RETIRED.ANY_P, inv=1, cmask=16 (cycles:p). */
634 	INTEL_FLAGS_EVENT_CONSTRAINT(0x108000c0, 0x01),
635 	/* Allow all events as PEBS with no flags */
636 	INTEL_ALL_EVENT_CONSTRAINT(0, 0x1),
637 	EVENT_CONSTRAINT_END
638 };
639 
640 struct event_constraint intel_slm_pebs_event_constraints[] = {
641 	/* INST_RETIRED.ANY_P, inv=1, cmask=16 (cycles:p). */
642 	INTEL_FLAGS_EVENT_CONSTRAINT(0x108000c0, 0x1),
643 	/* Allow all events as PEBS with no flags */
644 	INTEL_ALL_EVENT_CONSTRAINT(0, 0x1),
645 	EVENT_CONSTRAINT_END
646 };
647 
648 struct event_constraint intel_glm_pebs_event_constraints[] = {
649 	/* Allow all events as PEBS with no flags */
650 	INTEL_ALL_EVENT_CONSTRAINT(0, 0x1),
651 	EVENT_CONSTRAINT_END
652 };
653 
654 struct event_constraint intel_glp_pebs_event_constraints[] = {
655 	/* Allow all events as PEBS with no flags */
656 	INTEL_ALL_EVENT_CONSTRAINT(0, 0xf),
657 	EVENT_CONSTRAINT_END
658 };
659 
660 struct event_constraint intel_nehalem_pebs_event_constraints[] = {
661 	INTEL_PLD_CONSTRAINT(0x100b, 0xf),      /* MEM_INST_RETIRED.* */
662 	INTEL_FLAGS_EVENT_CONSTRAINT(0x0f, 0xf),    /* MEM_UNCORE_RETIRED.* */
663 	INTEL_FLAGS_UEVENT_CONSTRAINT(0x010c, 0xf), /* MEM_STORE_RETIRED.DTLB_MISS */
664 	INTEL_FLAGS_EVENT_CONSTRAINT(0xc0, 0xf),    /* INST_RETIRED.ANY */
665 	INTEL_EVENT_CONSTRAINT(0xc2, 0xf),    /* UOPS_RETIRED.* */
666 	INTEL_FLAGS_EVENT_CONSTRAINT(0xc4, 0xf),    /* BR_INST_RETIRED.* */
667 	INTEL_FLAGS_UEVENT_CONSTRAINT(0x02c5, 0xf), /* BR_MISP_RETIRED.NEAR_CALL */
668 	INTEL_FLAGS_EVENT_CONSTRAINT(0xc7, 0xf),    /* SSEX_UOPS_RETIRED.* */
669 	INTEL_FLAGS_UEVENT_CONSTRAINT(0x20c8, 0xf), /* ITLB_MISS_RETIRED */
670 	INTEL_FLAGS_EVENT_CONSTRAINT(0xcb, 0xf),    /* MEM_LOAD_RETIRED.* */
671 	INTEL_FLAGS_EVENT_CONSTRAINT(0xf7, 0xf),    /* FP_ASSIST.* */
672 	/* INST_RETIRED.ANY_P, inv=1, cmask=16 (cycles:p). */
673 	INTEL_FLAGS_EVENT_CONSTRAINT(0x108000c0, 0x0f),
674 	EVENT_CONSTRAINT_END
675 };
676 
677 struct event_constraint intel_westmere_pebs_event_constraints[] = {
678 	INTEL_PLD_CONSTRAINT(0x100b, 0xf),      /* MEM_INST_RETIRED.* */
679 	INTEL_FLAGS_EVENT_CONSTRAINT(0x0f, 0xf),    /* MEM_UNCORE_RETIRED.* */
680 	INTEL_FLAGS_UEVENT_CONSTRAINT(0x010c, 0xf), /* MEM_STORE_RETIRED.DTLB_MISS */
681 	INTEL_FLAGS_EVENT_CONSTRAINT(0xc0, 0xf),    /* INSTR_RETIRED.* */
682 	INTEL_EVENT_CONSTRAINT(0xc2, 0xf),    /* UOPS_RETIRED.* */
683 	INTEL_FLAGS_EVENT_CONSTRAINT(0xc4, 0xf),    /* BR_INST_RETIRED.* */
684 	INTEL_FLAGS_EVENT_CONSTRAINT(0xc5, 0xf),    /* BR_MISP_RETIRED.* */
685 	INTEL_FLAGS_EVENT_CONSTRAINT(0xc7, 0xf),    /* SSEX_UOPS_RETIRED.* */
686 	INTEL_FLAGS_UEVENT_CONSTRAINT(0x20c8, 0xf), /* ITLB_MISS_RETIRED */
687 	INTEL_FLAGS_EVENT_CONSTRAINT(0xcb, 0xf),    /* MEM_LOAD_RETIRED.* */
688 	INTEL_FLAGS_EVENT_CONSTRAINT(0xf7, 0xf),    /* FP_ASSIST.* */
689 	/* INST_RETIRED.ANY_P, inv=1, cmask=16 (cycles:p). */
690 	INTEL_FLAGS_EVENT_CONSTRAINT(0x108000c0, 0x0f),
691 	EVENT_CONSTRAINT_END
692 };
693 
694 struct event_constraint intel_snb_pebs_event_constraints[] = {
695 	INTEL_FLAGS_UEVENT_CONSTRAINT(0x01c0, 0x2), /* INST_RETIRED.PRECDIST */
696 	INTEL_PLD_CONSTRAINT(0x01cd, 0x8),    /* MEM_TRANS_RETIRED.LAT_ABOVE_THR */
697 	INTEL_PST_CONSTRAINT(0x02cd, 0x8),    /* MEM_TRANS_RETIRED.PRECISE_STORES */
698 	/* UOPS_RETIRED.ALL, inv=1, cmask=16 (cycles:p). */
699 	INTEL_FLAGS_EVENT_CONSTRAINT(0x108001c2, 0xf),
700         INTEL_EXCLEVT_CONSTRAINT(0xd0, 0xf),    /* MEM_UOP_RETIRED.* */
701         INTEL_EXCLEVT_CONSTRAINT(0xd1, 0xf),    /* MEM_LOAD_UOPS_RETIRED.* */
702         INTEL_EXCLEVT_CONSTRAINT(0xd2, 0xf),    /* MEM_LOAD_UOPS_LLC_HIT_RETIRED.* */
703         INTEL_EXCLEVT_CONSTRAINT(0xd3, 0xf),    /* MEM_LOAD_UOPS_LLC_MISS_RETIRED.* */
704 	/* Allow all events as PEBS with no flags */
705 	INTEL_ALL_EVENT_CONSTRAINT(0, 0xf),
706 	EVENT_CONSTRAINT_END
707 };
708 
709 struct event_constraint intel_ivb_pebs_event_constraints[] = {
710         INTEL_FLAGS_UEVENT_CONSTRAINT(0x01c0, 0x2), /* INST_RETIRED.PRECDIST */
711         INTEL_PLD_CONSTRAINT(0x01cd, 0x8),    /* MEM_TRANS_RETIRED.LAT_ABOVE_THR */
712 	INTEL_PST_CONSTRAINT(0x02cd, 0x8),    /* MEM_TRANS_RETIRED.PRECISE_STORES */
713 	/* UOPS_RETIRED.ALL, inv=1, cmask=16 (cycles:p). */
714 	INTEL_FLAGS_EVENT_CONSTRAINT(0x108001c2, 0xf),
715 	/* INST_RETIRED.PREC_DIST, inv=1, cmask=16 (cycles:ppp). */
716 	INTEL_FLAGS_EVENT_CONSTRAINT(0x108001c0, 0x2),
717 	INTEL_EXCLEVT_CONSTRAINT(0xd0, 0xf),    /* MEM_UOP_RETIRED.* */
718 	INTEL_EXCLEVT_CONSTRAINT(0xd1, 0xf),    /* MEM_LOAD_UOPS_RETIRED.* */
719 	INTEL_EXCLEVT_CONSTRAINT(0xd2, 0xf),    /* MEM_LOAD_UOPS_LLC_HIT_RETIRED.* */
720 	INTEL_EXCLEVT_CONSTRAINT(0xd3, 0xf),    /* MEM_LOAD_UOPS_LLC_MISS_RETIRED.* */
721 	/* Allow all events as PEBS with no flags */
722 	INTEL_ALL_EVENT_CONSTRAINT(0, 0xf),
723         EVENT_CONSTRAINT_END
724 };
725 
726 struct event_constraint intel_hsw_pebs_event_constraints[] = {
727 	INTEL_FLAGS_UEVENT_CONSTRAINT(0x01c0, 0x2), /* INST_RETIRED.PRECDIST */
728 	INTEL_PLD_CONSTRAINT(0x01cd, 0xf),    /* MEM_TRANS_RETIRED.* */
729 	/* UOPS_RETIRED.ALL, inv=1, cmask=16 (cycles:p). */
730 	INTEL_FLAGS_EVENT_CONSTRAINT(0x108001c2, 0xf),
731 	/* INST_RETIRED.PREC_DIST, inv=1, cmask=16 (cycles:ppp). */
732 	INTEL_FLAGS_EVENT_CONSTRAINT(0x108001c0, 0x2),
733 	INTEL_FLAGS_UEVENT_CONSTRAINT_DATALA_NA(0x01c2, 0xf), /* UOPS_RETIRED.ALL */
734 	INTEL_FLAGS_UEVENT_CONSTRAINT_DATALA_XLD(0x11d0, 0xf), /* MEM_UOPS_RETIRED.STLB_MISS_LOADS */
735 	INTEL_FLAGS_UEVENT_CONSTRAINT_DATALA_XLD(0x21d0, 0xf), /* MEM_UOPS_RETIRED.LOCK_LOADS */
736 	INTEL_FLAGS_UEVENT_CONSTRAINT_DATALA_XLD(0x41d0, 0xf), /* MEM_UOPS_RETIRED.SPLIT_LOADS */
737 	INTEL_FLAGS_UEVENT_CONSTRAINT_DATALA_XLD(0x81d0, 0xf), /* MEM_UOPS_RETIRED.ALL_LOADS */
738 	INTEL_FLAGS_UEVENT_CONSTRAINT_DATALA_XST(0x12d0, 0xf), /* MEM_UOPS_RETIRED.STLB_MISS_STORES */
739 	INTEL_FLAGS_UEVENT_CONSTRAINT_DATALA_XST(0x42d0, 0xf), /* MEM_UOPS_RETIRED.SPLIT_STORES */
740 	INTEL_FLAGS_UEVENT_CONSTRAINT_DATALA_XST(0x82d0, 0xf), /* MEM_UOPS_RETIRED.ALL_STORES */
741 	INTEL_FLAGS_EVENT_CONSTRAINT_DATALA_XLD(0xd1, 0xf),    /* MEM_LOAD_UOPS_RETIRED.* */
742 	INTEL_FLAGS_EVENT_CONSTRAINT_DATALA_XLD(0xd2, 0xf),    /* MEM_LOAD_UOPS_L3_HIT_RETIRED.* */
743 	INTEL_FLAGS_EVENT_CONSTRAINT_DATALA_XLD(0xd3, 0xf),    /* MEM_LOAD_UOPS_L3_MISS_RETIRED.* */
744 	/* Allow all events as PEBS with no flags */
745 	INTEL_ALL_EVENT_CONSTRAINT(0, 0xf),
746 	EVENT_CONSTRAINT_END
747 };
748 
749 struct event_constraint intel_bdw_pebs_event_constraints[] = {
750 	INTEL_FLAGS_UEVENT_CONSTRAINT(0x01c0, 0x2), /* INST_RETIRED.PRECDIST */
751 	INTEL_PLD_CONSTRAINT(0x01cd, 0xf),    /* MEM_TRANS_RETIRED.* */
752 	/* UOPS_RETIRED.ALL, inv=1, cmask=16 (cycles:p). */
753 	INTEL_FLAGS_EVENT_CONSTRAINT(0x108001c2, 0xf),
754 	/* INST_RETIRED.PREC_DIST, inv=1, cmask=16 (cycles:ppp). */
755 	INTEL_FLAGS_EVENT_CONSTRAINT(0x108001c0, 0x2),
756 	INTEL_FLAGS_UEVENT_CONSTRAINT_DATALA_NA(0x01c2, 0xf), /* UOPS_RETIRED.ALL */
757 	INTEL_FLAGS_UEVENT_CONSTRAINT_DATALA_LD(0x11d0, 0xf), /* MEM_UOPS_RETIRED.STLB_MISS_LOADS */
758 	INTEL_FLAGS_UEVENT_CONSTRAINT_DATALA_LD(0x21d0, 0xf), /* MEM_UOPS_RETIRED.LOCK_LOADS */
759 	INTEL_FLAGS_UEVENT_CONSTRAINT_DATALA_LD(0x41d0, 0xf), /* MEM_UOPS_RETIRED.SPLIT_LOADS */
760 	INTEL_FLAGS_UEVENT_CONSTRAINT_DATALA_LD(0x81d0, 0xf), /* MEM_UOPS_RETIRED.ALL_LOADS */
761 	INTEL_FLAGS_UEVENT_CONSTRAINT_DATALA_ST(0x12d0, 0xf), /* MEM_UOPS_RETIRED.STLB_MISS_STORES */
762 	INTEL_FLAGS_UEVENT_CONSTRAINT_DATALA_ST(0x42d0, 0xf), /* MEM_UOPS_RETIRED.SPLIT_STORES */
763 	INTEL_FLAGS_UEVENT_CONSTRAINT_DATALA_ST(0x82d0, 0xf), /* MEM_UOPS_RETIRED.ALL_STORES */
764 	INTEL_FLAGS_EVENT_CONSTRAINT_DATALA_LD(0xd1, 0xf),    /* MEM_LOAD_UOPS_RETIRED.* */
765 	INTEL_FLAGS_EVENT_CONSTRAINT_DATALA_LD(0xd2, 0xf),    /* MEM_LOAD_UOPS_L3_HIT_RETIRED.* */
766 	INTEL_FLAGS_EVENT_CONSTRAINT_DATALA_LD(0xd3, 0xf),    /* MEM_LOAD_UOPS_L3_MISS_RETIRED.* */
767 	/* Allow all events as PEBS with no flags */
768 	INTEL_ALL_EVENT_CONSTRAINT(0, 0xf),
769 	EVENT_CONSTRAINT_END
770 };
771 
772 
773 struct event_constraint intel_skl_pebs_event_constraints[] = {
774 	INTEL_FLAGS_UEVENT_CONSTRAINT(0x1c0, 0x2),	/* INST_RETIRED.PREC_DIST */
775 	/* INST_RETIRED.PREC_DIST, inv=1, cmask=16 (cycles:ppp). */
776 	INTEL_FLAGS_EVENT_CONSTRAINT(0x108001c0, 0x2),
777 	/* INST_RETIRED.TOTAL_CYCLES_PS (inv=1, cmask=16) (cycles:p). */
778 	INTEL_FLAGS_EVENT_CONSTRAINT(0x108000c0, 0x0f),
779 	INTEL_PLD_CONSTRAINT(0x1cd, 0xf),		      /* MEM_TRANS_RETIRED.* */
780 	INTEL_FLAGS_UEVENT_CONSTRAINT_DATALA_LD(0x11d0, 0xf), /* MEM_INST_RETIRED.STLB_MISS_LOADS */
781 	INTEL_FLAGS_UEVENT_CONSTRAINT_DATALA_ST(0x12d0, 0xf), /* MEM_INST_RETIRED.STLB_MISS_STORES */
782 	INTEL_FLAGS_UEVENT_CONSTRAINT_DATALA_LD(0x21d0, 0xf), /* MEM_INST_RETIRED.LOCK_LOADS */
783 	INTEL_FLAGS_UEVENT_CONSTRAINT_DATALA_ST(0x22d0, 0xf), /* MEM_INST_RETIRED.LOCK_STORES */
784 	INTEL_FLAGS_UEVENT_CONSTRAINT_DATALA_LD(0x41d0, 0xf), /* MEM_INST_RETIRED.SPLIT_LOADS */
785 	INTEL_FLAGS_UEVENT_CONSTRAINT_DATALA_ST(0x42d0, 0xf), /* MEM_INST_RETIRED.SPLIT_STORES */
786 	INTEL_FLAGS_UEVENT_CONSTRAINT_DATALA_LD(0x81d0, 0xf), /* MEM_INST_RETIRED.ALL_LOADS */
787 	INTEL_FLAGS_UEVENT_CONSTRAINT_DATALA_ST(0x82d0, 0xf), /* MEM_INST_RETIRED.ALL_STORES */
788 	INTEL_FLAGS_EVENT_CONSTRAINT_DATALA_LD(0xd1, 0xf),    /* MEM_LOAD_RETIRED.* */
789 	INTEL_FLAGS_EVENT_CONSTRAINT_DATALA_LD(0xd2, 0xf),    /* MEM_LOAD_L3_HIT_RETIRED.* */
790 	INTEL_FLAGS_EVENT_CONSTRAINT_DATALA_LD(0xd3, 0xf),    /* MEM_LOAD_L3_MISS_RETIRED.* */
791 	/* Allow all events as PEBS with no flags */
792 	INTEL_ALL_EVENT_CONSTRAINT(0, 0xf),
793 	EVENT_CONSTRAINT_END
794 };
795 
796 struct event_constraint *intel_pebs_constraints(struct perf_event *event)
797 {
798 	struct event_constraint *c;
799 
800 	if (!event->attr.precise_ip)
801 		return NULL;
802 
803 	if (x86_pmu.pebs_constraints) {
804 		for_each_event_constraint(c, x86_pmu.pebs_constraints) {
805 			if ((event->hw.config & c->cmask) == c->code) {
806 				event->hw.flags |= c->flags;
807 				return c;
808 			}
809 		}
810 	}
811 
812 	return &emptyconstraint;
813 }
814 
815 /*
816  * We need the sched_task callback even for per-cpu events when we use
817  * the large interrupt threshold, such that we can provide PID and TID
818  * to PEBS samples.
819  */
820 static inline bool pebs_needs_sched_cb(struct cpu_hw_events *cpuc)
821 {
822 	return cpuc->n_pebs && (cpuc->n_pebs == cpuc->n_large_pebs);
823 }
824 
825 static inline void pebs_update_threshold(struct cpu_hw_events *cpuc)
826 {
827 	struct debug_store *ds = cpuc->ds;
828 	u64 threshold;
829 
830 	if (cpuc->n_pebs == cpuc->n_large_pebs) {
831 		threshold = ds->pebs_absolute_maximum -
832 			x86_pmu.max_pebs_events * x86_pmu.pebs_record_size;
833 	} else {
834 		threshold = ds->pebs_buffer_base + x86_pmu.pebs_record_size;
835 	}
836 
837 	ds->pebs_interrupt_threshold = threshold;
838 }
839 
840 static void
841 pebs_update_state(bool needed_cb, struct cpu_hw_events *cpuc, struct pmu *pmu)
842 {
843 	/*
844 	 * Make sure we get updated with the first PEBS
845 	 * event. It will trigger also during removal, but
846 	 * that does not hurt:
847 	 */
848 	bool update = cpuc->n_pebs == 1;
849 
850 	if (needed_cb != pebs_needs_sched_cb(cpuc)) {
851 		if (!needed_cb)
852 			perf_sched_cb_inc(pmu);
853 		else
854 			perf_sched_cb_dec(pmu);
855 
856 		update = true;
857 	}
858 
859 	if (update)
860 		pebs_update_threshold(cpuc);
861 }
862 
863 void intel_pmu_pebs_add(struct perf_event *event)
864 {
865 	struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events);
866 	struct hw_perf_event *hwc = &event->hw;
867 	bool needed_cb = pebs_needs_sched_cb(cpuc);
868 
869 	cpuc->n_pebs++;
870 	if (hwc->flags & PERF_X86_EVENT_FREERUNNING)
871 		cpuc->n_large_pebs++;
872 
873 	pebs_update_state(needed_cb, cpuc, event->ctx->pmu);
874 }
875 
876 void intel_pmu_pebs_enable(struct perf_event *event)
877 {
878 	struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events);
879 	struct hw_perf_event *hwc = &event->hw;
880 	struct debug_store *ds = cpuc->ds;
881 
882 	hwc->config &= ~ARCH_PERFMON_EVENTSEL_INT;
883 
884 	cpuc->pebs_enabled |= 1ULL << hwc->idx;
885 
886 	if (event->hw.flags & PERF_X86_EVENT_PEBS_LDLAT)
887 		cpuc->pebs_enabled |= 1ULL << (hwc->idx + 32);
888 	else if (event->hw.flags & PERF_X86_EVENT_PEBS_ST)
889 		cpuc->pebs_enabled |= 1ULL << 63;
890 
891 	/*
892 	 * Use auto-reload if possible to save a MSR write in the PMI.
893 	 * This must be done in pmu::start(), because PERF_EVENT_IOC_PERIOD.
894 	 */
895 	if (hwc->flags & PERF_X86_EVENT_AUTO_RELOAD) {
896 		ds->pebs_event_reset[hwc->idx] =
897 			(u64)(-hwc->sample_period) & x86_pmu.cntval_mask;
898 	} else {
899 		ds->pebs_event_reset[hwc->idx] = 0;
900 	}
901 }
902 
903 void intel_pmu_pebs_del(struct perf_event *event)
904 {
905 	struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events);
906 	struct hw_perf_event *hwc = &event->hw;
907 	bool needed_cb = pebs_needs_sched_cb(cpuc);
908 
909 	cpuc->n_pebs--;
910 	if (hwc->flags & PERF_X86_EVENT_FREERUNNING)
911 		cpuc->n_large_pebs--;
912 
913 	pebs_update_state(needed_cb, cpuc, event->ctx->pmu);
914 }
915 
916 void intel_pmu_pebs_disable(struct perf_event *event)
917 {
918 	struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events);
919 	struct hw_perf_event *hwc = &event->hw;
920 
921 	if (cpuc->n_pebs == cpuc->n_large_pebs)
922 		intel_pmu_drain_pebs_buffer();
923 
924 	cpuc->pebs_enabled &= ~(1ULL << hwc->idx);
925 
926 	if (event->hw.flags & PERF_X86_EVENT_PEBS_LDLAT)
927 		cpuc->pebs_enabled &= ~(1ULL << (hwc->idx + 32));
928 	else if (event->hw.flags & PERF_X86_EVENT_PEBS_ST)
929 		cpuc->pebs_enabled &= ~(1ULL << 63);
930 
931 	if (cpuc->enabled)
932 		wrmsrl(MSR_IA32_PEBS_ENABLE, cpuc->pebs_enabled);
933 
934 	hwc->config |= ARCH_PERFMON_EVENTSEL_INT;
935 }
936 
937 void intel_pmu_pebs_enable_all(void)
938 {
939 	struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events);
940 
941 	if (cpuc->pebs_enabled)
942 		wrmsrl(MSR_IA32_PEBS_ENABLE, cpuc->pebs_enabled);
943 }
944 
945 void intel_pmu_pebs_disable_all(void)
946 {
947 	struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events);
948 
949 	if (cpuc->pebs_enabled)
950 		wrmsrl(MSR_IA32_PEBS_ENABLE, 0);
951 }
952 
953 static int intel_pmu_pebs_fixup_ip(struct pt_regs *regs)
954 {
955 	struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events);
956 	unsigned long from = cpuc->lbr_entries[0].from;
957 	unsigned long old_to, to = cpuc->lbr_entries[0].to;
958 	unsigned long ip = regs->ip;
959 	int is_64bit = 0;
960 	void *kaddr;
961 	int size;
962 
963 	/*
964 	 * We don't need to fixup if the PEBS assist is fault like
965 	 */
966 	if (!x86_pmu.intel_cap.pebs_trap)
967 		return 1;
968 
969 	/*
970 	 * No LBR entry, no basic block, no rewinding
971 	 */
972 	if (!cpuc->lbr_stack.nr || !from || !to)
973 		return 0;
974 
975 	/*
976 	 * Basic blocks should never cross user/kernel boundaries
977 	 */
978 	if (kernel_ip(ip) != kernel_ip(to))
979 		return 0;
980 
981 	/*
982 	 * unsigned math, either ip is before the start (impossible) or
983 	 * the basic block is larger than 1 page (sanity)
984 	 */
985 	if ((ip - to) > PEBS_FIXUP_SIZE)
986 		return 0;
987 
988 	/*
989 	 * We sampled a branch insn, rewind using the LBR stack
990 	 */
991 	if (ip == to) {
992 		set_linear_ip(regs, from);
993 		return 1;
994 	}
995 
996 	size = ip - to;
997 	if (!kernel_ip(ip)) {
998 		int bytes;
999 		u8 *buf = this_cpu_read(insn_buffer);
1000 
1001 		/* 'size' must fit our buffer, see above */
1002 		bytes = copy_from_user_nmi(buf, (void __user *)to, size);
1003 		if (bytes != 0)
1004 			return 0;
1005 
1006 		kaddr = buf;
1007 	} else {
1008 		kaddr = (void *)to;
1009 	}
1010 
1011 	do {
1012 		struct insn insn;
1013 
1014 		old_to = to;
1015 
1016 #ifdef CONFIG_X86_64
1017 		is_64bit = kernel_ip(to) || !test_thread_flag(TIF_IA32);
1018 #endif
1019 		insn_init(&insn, kaddr, size, is_64bit);
1020 		insn_get_length(&insn);
1021 		/*
1022 		 * Make sure there was not a problem decoding the
1023 		 * instruction and getting the length.  This is
1024 		 * doubly important because we have an infinite
1025 		 * loop if insn.length=0.
1026 		 */
1027 		if (!insn.length)
1028 			break;
1029 
1030 		to += insn.length;
1031 		kaddr += insn.length;
1032 		size -= insn.length;
1033 	} while (to < ip);
1034 
1035 	if (to == ip) {
1036 		set_linear_ip(regs, old_to);
1037 		return 1;
1038 	}
1039 
1040 	/*
1041 	 * Even though we decoded the basic block, the instruction stream
1042 	 * never matched the given IP, either the TO or the IP got corrupted.
1043 	 */
1044 	return 0;
1045 }
1046 
1047 static inline u64 intel_hsw_weight(struct pebs_record_skl *pebs)
1048 {
1049 	if (pebs->tsx_tuning) {
1050 		union hsw_tsx_tuning tsx = { .value = pebs->tsx_tuning };
1051 		return tsx.cycles_last_block;
1052 	}
1053 	return 0;
1054 }
1055 
1056 static inline u64 intel_hsw_transaction(struct pebs_record_skl *pebs)
1057 {
1058 	u64 txn = (pebs->tsx_tuning & PEBS_HSW_TSX_FLAGS) >> 32;
1059 
1060 	/* For RTM XABORTs also log the abort code from AX */
1061 	if ((txn & PERF_TXN_TRANSACTION) && (pebs->ax & 1))
1062 		txn |= ((pebs->ax >> 24) & 0xff) << PERF_TXN_ABORT_SHIFT;
1063 	return txn;
1064 }
1065 
1066 static void setup_pebs_sample_data(struct perf_event *event,
1067 				   struct pt_regs *iregs, void *__pebs,
1068 				   struct perf_sample_data *data,
1069 				   struct pt_regs *regs)
1070 {
1071 #define PERF_X86_EVENT_PEBS_HSW_PREC \
1072 		(PERF_X86_EVENT_PEBS_ST_HSW | \
1073 		 PERF_X86_EVENT_PEBS_LD_HSW | \
1074 		 PERF_X86_EVENT_PEBS_NA_HSW)
1075 	/*
1076 	 * We cast to the biggest pebs_record but are careful not to
1077 	 * unconditionally access the 'extra' entries.
1078 	 */
1079 	struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events);
1080 	struct pebs_record_skl *pebs = __pebs;
1081 	u64 sample_type;
1082 	int fll, fst, dsrc;
1083 	int fl = event->hw.flags;
1084 
1085 	if (pebs == NULL)
1086 		return;
1087 
1088 	sample_type = event->attr.sample_type;
1089 	dsrc = sample_type & PERF_SAMPLE_DATA_SRC;
1090 
1091 	fll = fl & PERF_X86_EVENT_PEBS_LDLAT;
1092 	fst = fl & (PERF_X86_EVENT_PEBS_ST | PERF_X86_EVENT_PEBS_HSW_PREC);
1093 
1094 	perf_sample_data_init(data, 0, event->hw.last_period);
1095 
1096 	data->period = event->hw.last_period;
1097 
1098 	/*
1099 	 * Use latency for weight (only avail with PEBS-LL)
1100 	 */
1101 	if (fll && (sample_type & PERF_SAMPLE_WEIGHT))
1102 		data->weight = pebs->lat;
1103 
1104 	/*
1105 	 * data.data_src encodes the data source
1106 	 */
1107 	if (dsrc) {
1108 		u64 val = PERF_MEM_NA;
1109 		if (fll)
1110 			val = load_latency_data(pebs->dse);
1111 		else if (fst && (fl & PERF_X86_EVENT_PEBS_HSW_PREC))
1112 			val = precise_datala_hsw(event, pebs->dse);
1113 		else if (fst)
1114 			val = precise_store_data(pebs->dse);
1115 		data->data_src.val = val;
1116 	}
1117 
1118 	/*
1119 	 * We use the interrupt regs as a base because the PEBS record does not
1120 	 * contain a full regs set, specifically it seems to lack segment
1121 	 * descriptors, which get used by things like user_mode().
1122 	 *
1123 	 * In the simple case fix up only the IP for PERF_SAMPLE_IP.
1124 	 *
1125 	 * We must however always use BP,SP from iregs for the unwinder to stay
1126 	 * sane; the record BP,SP can point into thin air when the record is
1127 	 * from a previous PMI context or an (I)RET happend between the record
1128 	 * and PMI.
1129 	 */
1130 	*regs = *iregs;
1131 	regs->flags = pebs->flags;
1132 	set_linear_ip(regs, pebs->ip);
1133 
1134 	if (sample_type & PERF_SAMPLE_REGS_INTR) {
1135 		regs->ax = pebs->ax;
1136 		regs->bx = pebs->bx;
1137 		regs->cx = pebs->cx;
1138 		regs->dx = pebs->dx;
1139 		regs->si = pebs->si;
1140 		regs->di = pebs->di;
1141 
1142 		/*
1143 		 * Per the above; only set BP,SP if we don't need callchains.
1144 		 *
1145 		 * XXX: does this make sense?
1146 		 */
1147 		if (!(sample_type & PERF_SAMPLE_CALLCHAIN)) {
1148 			regs->bp = pebs->bp;
1149 			regs->sp = pebs->sp;
1150 		}
1151 
1152 		/*
1153 		 * Preserve PERF_EFLAGS_VM from set_linear_ip().
1154 		 */
1155 		regs->flags = pebs->flags | (regs->flags & PERF_EFLAGS_VM);
1156 #ifndef CONFIG_X86_32
1157 		regs->r8 = pebs->r8;
1158 		regs->r9 = pebs->r9;
1159 		regs->r10 = pebs->r10;
1160 		regs->r11 = pebs->r11;
1161 		regs->r12 = pebs->r12;
1162 		regs->r13 = pebs->r13;
1163 		regs->r14 = pebs->r14;
1164 		regs->r15 = pebs->r15;
1165 #endif
1166 	}
1167 
1168 	if (event->attr.precise_ip > 1 && x86_pmu.intel_cap.pebs_format >= 2) {
1169 		regs->ip = pebs->real_ip;
1170 		regs->flags |= PERF_EFLAGS_EXACT;
1171 	} else if (event->attr.precise_ip > 1 && intel_pmu_pebs_fixup_ip(regs))
1172 		regs->flags |= PERF_EFLAGS_EXACT;
1173 	else
1174 		regs->flags &= ~PERF_EFLAGS_EXACT;
1175 
1176 	if ((sample_type & PERF_SAMPLE_ADDR) &&
1177 	    x86_pmu.intel_cap.pebs_format >= 1)
1178 		data->addr = pebs->dla;
1179 
1180 	if (x86_pmu.intel_cap.pebs_format >= 2) {
1181 		/* Only set the TSX weight when no memory weight. */
1182 		if ((sample_type & PERF_SAMPLE_WEIGHT) && !fll)
1183 			data->weight = intel_hsw_weight(pebs);
1184 
1185 		if (sample_type & PERF_SAMPLE_TRANSACTION)
1186 			data->txn = intel_hsw_transaction(pebs);
1187 	}
1188 
1189 	/*
1190 	 * v3 supplies an accurate time stamp, so we use that
1191 	 * for the time stamp.
1192 	 *
1193 	 * We can only do this for the default trace clock.
1194 	 */
1195 	if (x86_pmu.intel_cap.pebs_format >= 3 &&
1196 		event->attr.use_clockid == 0)
1197 		data->time = native_sched_clock_from_tsc(pebs->tsc);
1198 
1199 	if (has_branch_stack(event))
1200 		data->br_stack = &cpuc->lbr_stack;
1201 }
1202 
1203 static inline void *
1204 get_next_pebs_record_by_bit(void *base, void *top, int bit)
1205 {
1206 	struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events);
1207 	void *at;
1208 	u64 pebs_status;
1209 
1210 	/*
1211 	 * fmt0 does not have a status bitfield (does not use
1212 	 * perf_record_nhm format)
1213 	 */
1214 	if (x86_pmu.intel_cap.pebs_format < 1)
1215 		return base;
1216 
1217 	if (base == NULL)
1218 		return NULL;
1219 
1220 	for (at = base; at < top; at += x86_pmu.pebs_record_size) {
1221 		struct pebs_record_nhm *p = at;
1222 
1223 		if (test_bit(bit, (unsigned long *)&p->status)) {
1224 			/* PEBS v3 has accurate status bits */
1225 			if (x86_pmu.intel_cap.pebs_format >= 3)
1226 				return at;
1227 
1228 			if (p->status == (1 << bit))
1229 				return at;
1230 
1231 			/* clear non-PEBS bit and re-check */
1232 			pebs_status = p->status & cpuc->pebs_enabled;
1233 			pebs_status &= PEBS_COUNTER_MASK;
1234 			if (pebs_status == (1 << bit))
1235 				return at;
1236 		}
1237 	}
1238 	return NULL;
1239 }
1240 
1241 static void __intel_pmu_pebs_event(struct perf_event *event,
1242 				   struct pt_regs *iregs,
1243 				   void *base, void *top,
1244 				   int bit, int count)
1245 {
1246 	struct perf_sample_data data;
1247 	struct pt_regs regs;
1248 	void *at = get_next_pebs_record_by_bit(base, top, bit);
1249 
1250 	if (!intel_pmu_save_and_restart(event) &&
1251 	    !(event->hw.flags & PERF_X86_EVENT_AUTO_RELOAD))
1252 		return;
1253 
1254 	while (count > 1) {
1255 		setup_pebs_sample_data(event, iregs, at, &data, &regs);
1256 		perf_event_output(event, &data, &regs);
1257 		at += x86_pmu.pebs_record_size;
1258 		at = get_next_pebs_record_by_bit(at, top, bit);
1259 		count--;
1260 	}
1261 
1262 	setup_pebs_sample_data(event, iregs, at, &data, &regs);
1263 
1264 	/*
1265 	 * All but the last records are processed.
1266 	 * The last one is left to be able to call the overflow handler.
1267 	 */
1268 	if (perf_event_overflow(event, &data, &regs)) {
1269 		x86_pmu_stop(event, 0);
1270 		return;
1271 	}
1272 
1273 }
1274 
1275 static void intel_pmu_drain_pebs_core(struct pt_regs *iregs)
1276 {
1277 	struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events);
1278 	struct debug_store *ds = cpuc->ds;
1279 	struct perf_event *event = cpuc->events[0]; /* PMC0 only */
1280 	struct pebs_record_core *at, *top;
1281 	int n;
1282 
1283 	if (!x86_pmu.pebs_active)
1284 		return;
1285 
1286 	at  = (struct pebs_record_core *)(unsigned long)ds->pebs_buffer_base;
1287 	top = (struct pebs_record_core *)(unsigned long)ds->pebs_index;
1288 
1289 	/*
1290 	 * Whatever else happens, drain the thing
1291 	 */
1292 	ds->pebs_index = ds->pebs_buffer_base;
1293 
1294 	if (!test_bit(0, cpuc->active_mask))
1295 		return;
1296 
1297 	WARN_ON_ONCE(!event);
1298 
1299 	if (!event->attr.precise_ip)
1300 		return;
1301 
1302 	n = top - at;
1303 	if (n <= 0)
1304 		return;
1305 
1306 	__intel_pmu_pebs_event(event, iregs, at, top, 0, n);
1307 }
1308 
1309 static void intel_pmu_drain_pebs_nhm(struct pt_regs *iregs)
1310 {
1311 	struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events);
1312 	struct debug_store *ds = cpuc->ds;
1313 	struct perf_event *event;
1314 	void *base, *at, *top;
1315 	short counts[MAX_PEBS_EVENTS] = {};
1316 	short error[MAX_PEBS_EVENTS] = {};
1317 	int bit, i;
1318 
1319 	if (!x86_pmu.pebs_active)
1320 		return;
1321 
1322 	base = (struct pebs_record_nhm *)(unsigned long)ds->pebs_buffer_base;
1323 	top = (struct pebs_record_nhm *)(unsigned long)ds->pebs_index;
1324 
1325 	ds->pebs_index = ds->pebs_buffer_base;
1326 
1327 	if (unlikely(base >= top))
1328 		return;
1329 
1330 	for (at = base; at < top; at += x86_pmu.pebs_record_size) {
1331 		struct pebs_record_nhm *p = at;
1332 		u64 pebs_status;
1333 
1334 		pebs_status = p->status & cpuc->pebs_enabled;
1335 		pebs_status &= (1ULL << x86_pmu.max_pebs_events) - 1;
1336 
1337 		/* PEBS v3 has more accurate status bits */
1338 		if (x86_pmu.intel_cap.pebs_format >= 3) {
1339 			for_each_set_bit(bit, (unsigned long *)&pebs_status,
1340 					 x86_pmu.max_pebs_events)
1341 				counts[bit]++;
1342 
1343 			continue;
1344 		}
1345 
1346 		/*
1347 		 * On some CPUs the PEBS status can be zero when PEBS is
1348 		 * racing with clearing of GLOBAL_STATUS.
1349 		 *
1350 		 * Normally we would drop that record, but in the
1351 		 * case when there is only a single active PEBS event
1352 		 * we can assume it's for that event.
1353 		 */
1354 		if (!pebs_status && cpuc->pebs_enabled &&
1355 			!(cpuc->pebs_enabled & (cpuc->pebs_enabled-1)))
1356 			pebs_status = cpuc->pebs_enabled;
1357 
1358 		bit = find_first_bit((unsigned long *)&pebs_status,
1359 					x86_pmu.max_pebs_events);
1360 		if (bit >= x86_pmu.max_pebs_events)
1361 			continue;
1362 
1363 		/*
1364 		 * The PEBS hardware does not deal well with the situation
1365 		 * when events happen near to each other and multiple bits
1366 		 * are set. But it should happen rarely.
1367 		 *
1368 		 * If these events include one PEBS and multiple non-PEBS
1369 		 * events, it doesn't impact PEBS record. The record will
1370 		 * be handled normally. (slow path)
1371 		 *
1372 		 * If these events include two or more PEBS events, the
1373 		 * records for the events can be collapsed into a single
1374 		 * one, and it's not possible to reconstruct all events
1375 		 * that caused the PEBS record. It's called collision.
1376 		 * If collision happened, the record will be dropped.
1377 		 */
1378 		if (p->status != (1ULL << bit)) {
1379 			for_each_set_bit(i, (unsigned long *)&pebs_status,
1380 					 x86_pmu.max_pebs_events)
1381 				error[i]++;
1382 			continue;
1383 		}
1384 
1385 		counts[bit]++;
1386 	}
1387 
1388 	for (bit = 0; bit < x86_pmu.max_pebs_events; bit++) {
1389 		if ((counts[bit] == 0) && (error[bit] == 0))
1390 			continue;
1391 
1392 		event = cpuc->events[bit];
1393 		if (WARN_ON_ONCE(!event))
1394 			continue;
1395 
1396 		if (WARN_ON_ONCE(!event->attr.precise_ip))
1397 			continue;
1398 
1399 		/* log dropped samples number */
1400 		if (error[bit]) {
1401 			perf_log_lost_samples(event, error[bit]);
1402 
1403 			if (perf_event_account_interrupt(event))
1404 				x86_pmu_stop(event, 0);
1405 		}
1406 
1407 		if (counts[bit]) {
1408 			__intel_pmu_pebs_event(event, iregs, base,
1409 					       top, bit, counts[bit]);
1410 		}
1411 	}
1412 }
1413 
1414 /*
1415  * BTS, PEBS probe and setup
1416  */
1417 
1418 void __init intel_ds_init(void)
1419 {
1420 	/*
1421 	 * No support for 32bit formats
1422 	 */
1423 	if (!boot_cpu_has(X86_FEATURE_DTES64))
1424 		return;
1425 
1426 	x86_pmu.bts  = boot_cpu_has(X86_FEATURE_BTS);
1427 	x86_pmu.pebs = boot_cpu_has(X86_FEATURE_PEBS);
1428 	x86_pmu.pebs_buffer_size = PEBS_BUFFER_SIZE;
1429 	if (x86_pmu.pebs) {
1430 		char pebs_type = x86_pmu.intel_cap.pebs_trap ?  '+' : '-';
1431 		int format = x86_pmu.intel_cap.pebs_format;
1432 
1433 		switch (format) {
1434 		case 0:
1435 			pr_cont("PEBS fmt0%c, ", pebs_type);
1436 			x86_pmu.pebs_record_size = sizeof(struct pebs_record_core);
1437 			/*
1438 			 * Using >PAGE_SIZE buffers makes the WRMSR to
1439 			 * PERF_GLOBAL_CTRL in intel_pmu_enable_all()
1440 			 * mysteriously hang on Core2.
1441 			 *
1442 			 * As a workaround, we don't do this.
1443 			 */
1444 			x86_pmu.pebs_buffer_size = PAGE_SIZE;
1445 			x86_pmu.drain_pebs = intel_pmu_drain_pebs_core;
1446 			break;
1447 
1448 		case 1:
1449 			pr_cont("PEBS fmt1%c, ", pebs_type);
1450 			x86_pmu.pebs_record_size = sizeof(struct pebs_record_nhm);
1451 			x86_pmu.drain_pebs = intel_pmu_drain_pebs_nhm;
1452 			break;
1453 
1454 		case 2:
1455 			pr_cont("PEBS fmt2%c, ", pebs_type);
1456 			x86_pmu.pebs_record_size = sizeof(struct pebs_record_hsw);
1457 			x86_pmu.drain_pebs = intel_pmu_drain_pebs_nhm;
1458 			break;
1459 
1460 		case 3:
1461 			pr_cont("PEBS fmt3%c, ", pebs_type);
1462 			x86_pmu.pebs_record_size =
1463 						sizeof(struct pebs_record_skl);
1464 			x86_pmu.drain_pebs = intel_pmu_drain_pebs_nhm;
1465 			x86_pmu.free_running_flags |= PERF_SAMPLE_TIME;
1466 			break;
1467 
1468 		default:
1469 			pr_cont("no PEBS fmt%d%c, ", format, pebs_type);
1470 			x86_pmu.pebs = 0;
1471 		}
1472 	}
1473 }
1474 
1475 void perf_restore_debug_store(void)
1476 {
1477 	struct debug_store *ds = __this_cpu_read(cpu_hw_events.ds);
1478 
1479 	if (!x86_pmu.bts && !x86_pmu.pebs)
1480 		return;
1481 
1482 	wrmsrl(MSR_IA32_DS_AREA, (unsigned long)ds);
1483 }
1484