xref: /openbmc/linux/tools/perf/util/evsel.c (revision f7777dcc)
1 /*
2  * Copyright (C) 2011, Red Hat Inc, Arnaldo Carvalho de Melo <acme@redhat.com>
3  *
4  * Parts came from builtin-{top,stat,record}.c, see those files for further
5  * copyright notes.
6  *
7  * Released under the GPL v2. (and only v2, not any later version)
8  */
9 
10 #include <byteswap.h>
11 #include <linux/bitops.h>
12 #include <lk/debugfs.h>
13 #include <traceevent/event-parse.h>
14 #include <linux/hw_breakpoint.h>
15 #include <linux/perf_event.h>
16 #include <sys/resource.h>
17 #include "asm/bug.h"
18 #include "evsel.h"
19 #include "evlist.h"
20 #include "util.h"
21 #include "cpumap.h"
22 #include "thread_map.h"
23 #include "target.h"
24 #include "perf_regs.h"
25 #include "debug.h"
26 
27 static struct {
28 	bool sample_id_all;
29 	bool exclude_guest;
30 	bool mmap2;
31 } perf_missing_features;
32 
33 #define FD(e, x, y) (*(int *)xyarray__entry(e->fd, x, y))
34 
35 int __perf_evsel__sample_size(u64 sample_type)
36 {
37 	u64 mask = sample_type & PERF_SAMPLE_MASK;
38 	int size = 0;
39 	int i;
40 
41 	for (i = 0; i < 64; i++) {
42 		if (mask & (1ULL << i))
43 			size++;
44 	}
45 
46 	size *= sizeof(u64);
47 
48 	return size;
49 }
50 
51 /**
52  * __perf_evsel__calc_id_pos - calculate id_pos.
53  * @sample_type: sample type
54  *
55  * This function returns the position of the event id (PERF_SAMPLE_ID or
56  * PERF_SAMPLE_IDENTIFIER) in a sample event i.e. in the array of struct
57  * sample_event.
58  */
59 static int __perf_evsel__calc_id_pos(u64 sample_type)
60 {
61 	int idx = 0;
62 
63 	if (sample_type & PERF_SAMPLE_IDENTIFIER)
64 		return 0;
65 
66 	if (!(sample_type & PERF_SAMPLE_ID))
67 		return -1;
68 
69 	if (sample_type & PERF_SAMPLE_IP)
70 		idx += 1;
71 
72 	if (sample_type & PERF_SAMPLE_TID)
73 		idx += 1;
74 
75 	if (sample_type & PERF_SAMPLE_TIME)
76 		idx += 1;
77 
78 	if (sample_type & PERF_SAMPLE_ADDR)
79 		idx += 1;
80 
81 	return idx;
82 }
83 
84 /**
85  * __perf_evsel__calc_is_pos - calculate is_pos.
86  * @sample_type: sample type
87  *
88  * This function returns the position (counting backwards) of the event id
89  * (PERF_SAMPLE_ID or PERF_SAMPLE_IDENTIFIER) in a non-sample event i.e. if
90  * sample_id_all is used there is an id sample appended to non-sample events.
91  */
92 static int __perf_evsel__calc_is_pos(u64 sample_type)
93 {
94 	int idx = 1;
95 
96 	if (sample_type & PERF_SAMPLE_IDENTIFIER)
97 		return 1;
98 
99 	if (!(sample_type & PERF_SAMPLE_ID))
100 		return -1;
101 
102 	if (sample_type & PERF_SAMPLE_CPU)
103 		idx += 1;
104 
105 	if (sample_type & PERF_SAMPLE_STREAM_ID)
106 		idx += 1;
107 
108 	return idx;
109 }
110 
111 void perf_evsel__calc_id_pos(struct perf_evsel *evsel)
112 {
113 	evsel->id_pos = __perf_evsel__calc_id_pos(evsel->attr.sample_type);
114 	evsel->is_pos = __perf_evsel__calc_is_pos(evsel->attr.sample_type);
115 }
116 
117 void hists__init(struct hists *hists)
118 {
119 	memset(hists, 0, sizeof(*hists));
120 	hists->entries_in_array[0] = hists->entries_in_array[1] = RB_ROOT;
121 	hists->entries_in = &hists->entries_in_array[0];
122 	hists->entries_collapsed = RB_ROOT;
123 	hists->entries = RB_ROOT;
124 	pthread_mutex_init(&hists->lock, NULL);
125 }
126 
127 void __perf_evsel__set_sample_bit(struct perf_evsel *evsel,
128 				  enum perf_event_sample_format bit)
129 {
130 	if (!(evsel->attr.sample_type & bit)) {
131 		evsel->attr.sample_type |= bit;
132 		evsel->sample_size += sizeof(u64);
133 		perf_evsel__calc_id_pos(evsel);
134 	}
135 }
136 
137 void __perf_evsel__reset_sample_bit(struct perf_evsel *evsel,
138 				    enum perf_event_sample_format bit)
139 {
140 	if (evsel->attr.sample_type & bit) {
141 		evsel->attr.sample_type &= ~bit;
142 		evsel->sample_size -= sizeof(u64);
143 		perf_evsel__calc_id_pos(evsel);
144 	}
145 }
146 
147 void perf_evsel__set_sample_id(struct perf_evsel *evsel,
148 			       bool can_sample_identifier)
149 {
150 	if (can_sample_identifier) {
151 		perf_evsel__reset_sample_bit(evsel, ID);
152 		perf_evsel__set_sample_bit(evsel, IDENTIFIER);
153 	} else {
154 		perf_evsel__set_sample_bit(evsel, ID);
155 	}
156 	evsel->attr.read_format |= PERF_FORMAT_ID;
157 }
158 
159 void perf_evsel__init(struct perf_evsel *evsel,
160 		      struct perf_event_attr *attr, int idx)
161 {
162 	evsel->idx	   = idx;
163 	evsel->attr	   = *attr;
164 	evsel->leader	   = evsel;
165 	INIT_LIST_HEAD(&evsel->node);
166 	hists__init(&evsel->hists);
167 	evsel->sample_size = __perf_evsel__sample_size(attr->sample_type);
168 	perf_evsel__calc_id_pos(evsel);
169 }
170 
171 struct perf_evsel *perf_evsel__new(struct perf_event_attr *attr, int idx)
172 {
173 	struct perf_evsel *evsel = zalloc(sizeof(*evsel));
174 
175 	if (evsel != NULL)
176 		perf_evsel__init(evsel, attr, idx);
177 
178 	return evsel;
179 }
180 
181 struct event_format *event_format__new(const char *sys, const char *name)
182 {
183 	int fd, n;
184 	char *filename;
185 	void *bf = NULL, *nbf;
186 	size_t size = 0, alloc_size = 0;
187 	struct event_format *format = NULL;
188 
189 	if (asprintf(&filename, "%s/%s/%s/format", tracing_events_path, sys, name) < 0)
190 		goto out;
191 
192 	fd = open(filename, O_RDONLY);
193 	if (fd < 0)
194 		goto out_free_filename;
195 
196 	do {
197 		if (size == alloc_size) {
198 			alloc_size += BUFSIZ;
199 			nbf = realloc(bf, alloc_size);
200 			if (nbf == NULL)
201 				goto out_free_bf;
202 			bf = nbf;
203 		}
204 
205 		n = read(fd, bf + size, alloc_size - size);
206 		if (n < 0)
207 			goto out_free_bf;
208 		size += n;
209 	} while (n > 0);
210 
211 	pevent_parse_format(&format, bf, size, sys);
212 
213 out_free_bf:
214 	free(bf);
215 	close(fd);
216 out_free_filename:
217 	free(filename);
218 out:
219 	return format;
220 }
221 
222 struct perf_evsel *perf_evsel__newtp(const char *sys, const char *name, int idx)
223 {
224 	struct perf_evsel *evsel = zalloc(sizeof(*evsel));
225 
226 	if (evsel != NULL) {
227 		struct perf_event_attr attr = {
228 			.type	       = PERF_TYPE_TRACEPOINT,
229 			.sample_type   = (PERF_SAMPLE_RAW | PERF_SAMPLE_TIME |
230 					  PERF_SAMPLE_CPU | PERF_SAMPLE_PERIOD),
231 		};
232 
233 		if (asprintf(&evsel->name, "%s:%s", sys, name) < 0)
234 			goto out_free;
235 
236 		evsel->tp_format = event_format__new(sys, name);
237 		if (evsel->tp_format == NULL)
238 			goto out_free;
239 
240 		event_attr_init(&attr);
241 		attr.config = evsel->tp_format->id;
242 		attr.sample_period = 1;
243 		perf_evsel__init(evsel, &attr, idx);
244 	}
245 
246 	return evsel;
247 
248 out_free:
249 	free(evsel->name);
250 	free(evsel);
251 	return NULL;
252 }
253 
254 const char *perf_evsel__hw_names[PERF_COUNT_HW_MAX] = {
255 	"cycles",
256 	"instructions",
257 	"cache-references",
258 	"cache-misses",
259 	"branches",
260 	"branch-misses",
261 	"bus-cycles",
262 	"stalled-cycles-frontend",
263 	"stalled-cycles-backend",
264 	"ref-cycles",
265 };
266 
267 static const char *__perf_evsel__hw_name(u64 config)
268 {
269 	if (config < PERF_COUNT_HW_MAX && perf_evsel__hw_names[config])
270 		return perf_evsel__hw_names[config];
271 
272 	return "unknown-hardware";
273 }
274 
275 static int perf_evsel__add_modifiers(struct perf_evsel *evsel, char *bf, size_t size)
276 {
277 	int colon = 0, r = 0;
278 	struct perf_event_attr *attr = &evsel->attr;
279 	bool exclude_guest_default = false;
280 
281 #define MOD_PRINT(context, mod)	do {					\
282 		if (!attr->exclude_##context) {				\
283 			if (!colon) colon = ++r;			\
284 			r += scnprintf(bf + r, size - r, "%c", mod);	\
285 		} } while(0)
286 
287 	if (attr->exclude_kernel || attr->exclude_user || attr->exclude_hv) {
288 		MOD_PRINT(kernel, 'k');
289 		MOD_PRINT(user, 'u');
290 		MOD_PRINT(hv, 'h');
291 		exclude_guest_default = true;
292 	}
293 
294 	if (attr->precise_ip) {
295 		if (!colon)
296 			colon = ++r;
297 		r += scnprintf(bf + r, size - r, "%.*s", attr->precise_ip, "ppp");
298 		exclude_guest_default = true;
299 	}
300 
301 	if (attr->exclude_host || attr->exclude_guest == exclude_guest_default) {
302 		MOD_PRINT(host, 'H');
303 		MOD_PRINT(guest, 'G');
304 	}
305 #undef MOD_PRINT
306 	if (colon)
307 		bf[colon - 1] = ':';
308 	return r;
309 }
310 
311 static int perf_evsel__hw_name(struct perf_evsel *evsel, char *bf, size_t size)
312 {
313 	int r = scnprintf(bf, size, "%s", __perf_evsel__hw_name(evsel->attr.config));
314 	return r + perf_evsel__add_modifiers(evsel, bf + r, size - r);
315 }
316 
317 const char *perf_evsel__sw_names[PERF_COUNT_SW_MAX] = {
318 	"cpu-clock",
319 	"task-clock",
320 	"page-faults",
321 	"context-switches",
322 	"cpu-migrations",
323 	"minor-faults",
324 	"major-faults",
325 	"alignment-faults",
326 	"emulation-faults",
327 	"dummy",
328 };
329 
330 static const char *__perf_evsel__sw_name(u64 config)
331 {
332 	if (config < PERF_COUNT_SW_MAX && perf_evsel__sw_names[config])
333 		return perf_evsel__sw_names[config];
334 	return "unknown-software";
335 }
336 
337 static int perf_evsel__sw_name(struct perf_evsel *evsel, char *bf, size_t size)
338 {
339 	int r = scnprintf(bf, size, "%s", __perf_evsel__sw_name(evsel->attr.config));
340 	return r + perf_evsel__add_modifiers(evsel, bf + r, size - r);
341 }
342 
343 static int __perf_evsel__bp_name(char *bf, size_t size, u64 addr, u64 type)
344 {
345 	int r;
346 
347 	r = scnprintf(bf, size, "mem:0x%" PRIx64 ":", addr);
348 
349 	if (type & HW_BREAKPOINT_R)
350 		r += scnprintf(bf + r, size - r, "r");
351 
352 	if (type & HW_BREAKPOINT_W)
353 		r += scnprintf(bf + r, size - r, "w");
354 
355 	if (type & HW_BREAKPOINT_X)
356 		r += scnprintf(bf + r, size - r, "x");
357 
358 	return r;
359 }
360 
361 static int perf_evsel__bp_name(struct perf_evsel *evsel, char *bf, size_t size)
362 {
363 	struct perf_event_attr *attr = &evsel->attr;
364 	int r = __perf_evsel__bp_name(bf, size, attr->bp_addr, attr->bp_type);
365 	return r + perf_evsel__add_modifiers(evsel, bf + r, size - r);
366 }
367 
368 const char *perf_evsel__hw_cache[PERF_COUNT_HW_CACHE_MAX]
369 				[PERF_EVSEL__MAX_ALIASES] = {
370  { "L1-dcache",	"l1-d",		"l1d",		"L1-data",		},
371  { "L1-icache",	"l1-i",		"l1i",		"L1-instruction",	},
372  { "LLC",	"L2",							},
373  { "dTLB",	"d-tlb",	"Data-TLB",				},
374  { "iTLB",	"i-tlb",	"Instruction-TLB",			},
375  { "branch",	"branches",	"bpu",		"btb",		"bpc",	},
376  { "node",								},
377 };
378 
379 const char *perf_evsel__hw_cache_op[PERF_COUNT_HW_CACHE_OP_MAX]
380 				   [PERF_EVSEL__MAX_ALIASES] = {
381  { "load",	"loads",	"read",					},
382  { "store",	"stores",	"write",				},
383  { "prefetch",	"prefetches",	"speculative-read", "speculative-load",	},
384 };
385 
386 const char *perf_evsel__hw_cache_result[PERF_COUNT_HW_CACHE_RESULT_MAX]
387 				       [PERF_EVSEL__MAX_ALIASES] = {
388  { "refs",	"Reference",	"ops",		"access",		},
389  { "misses",	"miss",							},
390 };
391 
392 #define C(x)		PERF_COUNT_HW_CACHE_##x
393 #define CACHE_READ	(1 << C(OP_READ))
394 #define CACHE_WRITE	(1 << C(OP_WRITE))
395 #define CACHE_PREFETCH	(1 << C(OP_PREFETCH))
396 #define COP(x)		(1 << x)
397 
398 /*
399  * cache operartion stat
400  * L1I : Read and prefetch only
401  * ITLB and BPU : Read-only
402  */
403 static unsigned long perf_evsel__hw_cache_stat[C(MAX)] = {
404  [C(L1D)]	= (CACHE_READ | CACHE_WRITE | CACHE_PREFETCH),
405  [C(L1I)]	= (CACHE_READ | CACHE_PREFETCH),
406  [C(LL)]	= (CACHE_READ | CACHE_WRITE | CACHE_PREFETCH),
407  [C(DTLB)]	= (CACHE_READ | CACHE_WRITE | CACHE_PREFETCH),
408  [C(ITLB)]	= (CACHE_READ),
409  [C(BPU)]	= (CACHE_READ),
410  [C(NODE)]	= (CACHE_READ | CACHE_WRITE | CACHE_PREFETCH),
411 };
412 
413 bool perf_evsel__is_cache_op_valid(u8 type, u8 op)
414 {
415 	if (perf_evsel__hw_cache_stat[type] & COP(op))
416 		return true;	/* valid */
417 	else
418 		return false;	/* invalid */
419 }
420 
421 int __perf_evsel__hw_cache_type_op_res_name(u8 type, u8 op, u8 result,
422 					    char *bf, size_t size)
423 {
424 	if (result) {
425 		return scnprintf(bf, size, "%s-%s-%s", perf_evsel__hw_cache[type][0],
426 				 perf_evsel__hw_cache_op[op][0],
427 				 perf_evsel__hw_cache_result[result][0]);
428 	}
429 
430 	return scnprintf(bf, size, "%s-%s", perf_evsel__hw_cache[type][0],
431 			 perf_evsel__hw_cache_op[op][1]);
432 }
433 
434 static int __perf_evsel__hw_cache_name(u64 config, char *bf, size_t size)
435 {
436 	u8 op, result, type = (config >>  0) & 0xff;
437 	const char *err = "unknown-ext-hardware-cache-type";
438 
439 	if (type > PERF_COUNT_HW_CACHE_MAX)
440 		goto out_err;
441 
442 	op = (config >>  8) & 0xff;
443 	err = "unknown-ext-hardware-cache-op";
444 	if (op > PERF_COUNT_HW_CACHE_OP_MAX)
445 		goto out_err;
446 
447 	result = (config >> 16) & 0xff;
448 	err = "unknown-ext-hardware-cache-result";
449 	if (result > PERF_COUNT_HW_CACHE_RESULT_MAX)
450 		goto out_err;
451 
452 	err = "invalid-cache";
453 	if (!perf_evsel__is_cache_op_valid(type, op))
454 		goto out_err;
455 
456 	return __perf_evsel__hw_cache_type_op_res_name(type, op, result, bf, size);
457 out_err:
458 	return scnprintf(bf, size, "%s", err);
459 }
460 
461 static int perf_evsel__hw_cache_name(struct perf_evsel *evsel, char *bf, size_t size)
462 {
463 	int ret = __perf_evsel__hw_cache_name(evsel->attr.config, bf, size);
464 	return ret + perf_evsel__add_modifiers(evsel, bf + ret, size - ret);
465 }
466 
467 static int perf_evsel__raw_name(struct perf_evsel *evsel, char *bf, size_t size)
468 {
469 	int ret = scnprintf(bf, size, "raw 0x%" PRIx64, evsel->attr.config);
470 	return ret + perf_evsel__add_modifiers(evsel, bf + ret, size - ret);
471 }
472 
473 const char *perf_evsel__name(struct perf_evsel *evsel)
474 {
475 	char bf[128];
476 
477 	if (evsel->name)
478 		return evsel->name;
479 
480 	switch (evsel->attr.type) {
481 	case PERF_TYPE_RAW:
482 		perf_evsel__raw_name(evsel, bf, sizeof(bf));
483 		break;
484 
485 	case PERF_TYPE_HARDWARE:
486 		perf_evsel__hw_name(evsel, bf, sizeof(bf));
487 		break;
488 
489 	case PERF_TYPE_HW_CACHE:
490 		perf_evsel__hw_cache_name(evsel, bf, sizeof(bf));
491 		break;
492 
493 	case PERF_TYPE_SOFTWARE:
494 		perf_evsel__sw_name(evsel, bf, sizeof(bf));
495 		break;
496 
497 	case PERF_TYPE_TRACEPOINT:
498 		scnprintf(bf, sizeof(bf), "%s", "unknown tracepoint");
499 		break;
500 
501 	case PERF_TYPE_BREAKPOINT:
502 		perf_evsel__bp_name(evsel, bf, sizeof(bf));
503 		break;
504 
505 	default:
506 		scnprintf(bf, sizeof(bf), "unknown attr type: %d",
507 			  evsel->attr.type);
508 		break;
509 	}
510 
511 	evsel->name = strdup(bf);
512 
513 	return evsel->name ?: "unknown";
514 }
515 
516 const char *perf_evsel__group_name(struct perf_evsel *evsel)
517 {
518 	return evsel->group_name ?: "anon group";
519 }
520 
521 int perf_evsel__group_desc(struct perf_evsel *evsel, char *buf, size_t size)
522 {
523 	int ret;
524 	struct perf_evsel *pos;
525 	const char *group_name = perf_evsel__group_name(evsel);
526 
527 	ret = scnprintf(buf, size, "%s", group_name);
528 
529 	ret += scnprintf(buf + ret, size - ret, " { %s",
530 			 perf_evsel__name(evsel));
531 
532 	for_each_group_member(pos, evsel)
533 		ret += scnprintf(buf + ret, size - ret, ", %s",
534 				 perf_evsel__name(pos));
535 
536 	ret += scnprintf(buf + ret, size - ret, " }");
537 
538 	return ret;
539 }
540 
541 /*
542  * The enable_on_exec/disabled value strategy:
543  *
544  *  1) For any type of traced program:
545  *    - all independent events and group leaders are disabled
546  *    - all group members are enabled
547  *
548  *     Group members are ruled by group leaders. They need to
549  *     be enabled, because the group scheduling relies on that.
550  *
551  *  2) For traced programs executed by perf:
552  *     - all independent events and group leaders have
553  *       enable_on_exec set
554  *     - we don't specifically enable or disable any event during
555  *       the record command
556  *
557  *     Independent events and group leaders are initially disabled
558  *     and get enabled by exec. Group members are ruled by group
559  *     leaders as stated in 1).
560  *
561  *  3) For traced programs attached by perf (pid/tid):
562  *     - we specifically enable or disable all events during
563  *       the record command
564  *
565  *     When attaching events to already running traced we
566  *     enable/disable events specifically, as there's no
567  *     initial traced exec call.
568  */
569 void perf_evsel__config(struct perf_evsel *evsel,
570 			struct perf_record_opts *opts)
571 {
572 	struct perf_evsel *leader = evsel->leader;
573 	struct perf_event_attr *attr = &evsel->attr;
574 	int track = !evsel->idx; /* only the first counter needs these */
575 
576 	attr->sample_id_all = perf_missing_features.sample_id_all ? 0 : 1;
577 	attr->inherit	    = !opts->no_inherit;
578 
579 	perf_evsel__set_sample_bit(evsel, IP);
580 	perf_evsel__set_sample_bit(evsel, TID);
581 
582 	if (evsel->sample_read) {
583 		perf_evsel__set_sample_bit(evsel, READ);
584 
585 		/*
586 		 * We need ID even in case of single event, because
587 		 * PERF_SAMPLE_READ process ID specific data.
588 		 */
589 		perf_evsel__set_sample_id(evsel, false);
590 
591 		/*
592 		 * Apply group format only if we belong to group
593 		 * with more than one members.
594 		 */
595 		if (leader->nr_members > 1) {
596 			attr->read_format |= PERF_FORMAT_GROUP;
597 			attr->inherit = 0;
598 		}
599 	}
600 
601 	/*
602 	 * We default some events to a 1 default interval. But keep
603 	 * it a weak assumption overridable by the user.
604 	 */
605 	if (!attr->sample_period || (opts->user_freq != UINT_MAX &&
606 				     opts->user_interval != ULLONG_MAX)) {
607 		if (opts->freq) {
608 			perf_evsel__set_sample_bit(evsel, PERIOD);
609 			attr->freq		= 1;
610 			attr->sample_freq	= opts->freq;
611 		} else {
612 			attr->sample_period = opts->default_interval;
613 		}
614 	}
615 
616 	/*
617 	 * Disable sampling for all group members other
618 	 * than leader in case leader 'leads' the sampling.
619 	 */
620 	if ((leader != evsel) && leader->sample_read) {
621 		attr->sample_freq   = 0;
622 		attr->sample_period = 0;
623 	}
624 
625 	if (opts->no_samples)
626 		attr->sample_freq = 0;
627 
628 	if (opts->inherit_stat)
629 		attr->inherit_stat = 1;
630 
631 	if (opts->sample_address) {
632 		perf_evsel__set_sample_bit(evsel, ADDR);
633 		attr->mmap_data = track;
634 	}
635 
636 	if (opts->call_graph) {
637 		perf_evsel__set_sample_bit(evsel, CALLCHAIN);
638 
639 		if (opts->call_graph == CALLCHAIN_DWARF) {
640 			perf_evsel__set_sample_bit(evsel, REGS_USER);
641 			perf_evsel__set_sample_bit(evsel, STACK_USER);
642 			attr->sample_regs_user = PERF_REGS_MASK;
643 			attr->sample_stack_user = opts->stack_dump_size;
644 			attr->exclude_callchain_user = 1;
645 		}
646 	}
647 
648 	if (perf_target__has_cpu(&opts->target))
649 		perf_evsel__set_sample_bit(evsel, CPU);
650 
651 	if (opts->period)
652 		perf_evsel__set_sample_bit(evsel, PERIOD);
653 
654 	if (!perf_missing_features.sample_id_all &&
655 	    (opts->sample_time || !opts->no_inherit ||
656 	     perf_target__has_cpu(&opts->target)))
657 		perf_evsel__set_sample_bit(evsel, TIME);
658 
659 	if (opts->raw_samples) {
660 		perf_evsel__set_sample_bit(evsel, TIME);
661 		perf_evsel__set_sample_bit(evsel, RAW);
662 		perf_evsel__set_sample_bit(evsel, CPU);
663 	}
664 
665 	if (opts->sample_address)
666 		attr->sample_type	|= PERF_SAMPLE_DATA_SRC;
667 
668 	if (opts->no_delay) {
669 		attr->watermark = 0;
670 		attr->wakeup_events = 1;
671 	}
672 	if (opts->branch_stack) {
673 		perf_evsel__set_sample_bit(evsel, BRANCH_STACK);
674 		attr->branch_sample_type = opts->branch_stack;
675 	}
676 
677 	if (opts->sample_weight)
678 		attr->sample_type	|= PERF_SAMPLE_WEIGHT;
679 
680 	attr->mmap  = track;
681 	attr->comm  = track;
682 
683 	/*
684 	 * XXX see the function comment above
685 	 *
686 	 * Disabling only independent events or group leaders,
687 	 * keeping group members enabled.
688 	 */
689 	if (perf_evsel__is_group_leader(evsel))
690 		attr->disabled = 1;
691 
692 	/*
693 	 * Setting enable_on_exec for independent events and
694 	 * group leaders for traced executed by perf.
695 	 */
696 	if (perf_target__none(&opts->target) && perf_evsel__is_group_leader(evsel))
697 		attr->enable_on_exec = 1;
698 }
699 
700 int perf_evsel__alloc_fd(struct perf_evsel *evsel, int ncpus, int nthreads)
701 {
702 	int cpu, thread;
703 	evsel->fd = xyarray__new(ncpus, nthreads, sizeof(int));
704 
705 	if (evsel->fd) {
706 		for (cpu = 0; cpu < ncpus; cpu++) {
707 			for (thread = 0; thread < nthreads; thread++) {
708 				FD(evsel, cpu, thread) = -1;
709 			}
710 		}
711 	}
712 
713 	return evsel->fd != NULL ? 0 : -ENOMEM;
714 }
715 
716 static int perf_evsel__run_ioctl(struct perf_evsel *evsel, int ncpus, int nthreads,
717 			  int ioc,  void *arg)
718 {
719 	int cpu, thread;
720 
721 	for (cpu = 0; cpu < ncpus; cpu++) {
722 		for (thread = 0; thread < nthreads; thread++) {
723 			int fd = FD(evsel, cpu, thread),
724 			    err = ioctl(fd, ioc, arg);
725 
726 			if (err)
727 				return err;
728 		}
729 	}
730 
731 	return 0;
732 }
733 
734 int perf_evsel__set_filter(struct perf_evsel *evsel, int ncpus, int nthreads,
735 			   const char *filter)
736 {
737 	return perf_evsel__run_ioctl(evsel, ncpus, nthreads,
738 				     PERF_EVENT_IOC_SET_FILTER,
739 				     (void *)filter);
740 }
741 
742 int perf_evsel__enable(struct perf_evsel *evsel, int ncpus, int nthreads)
743 {
744 	return perf_evsel__run_ioctl(evsel, ncpus, nthreads,
745 				     PERF_EVENT_IOC_ENABLE,
746 				     0);
747 }
748 
749 int perf_evsel__alloc_id(struct perf_evsel *evsel, int ncpus, int nthreads)
750 {
751 	evsel->sample_id = xyarray__new(ncpus, nthreads, sizeof(struct perf_sample_id));
752 	if (evsel->sample_id == NULL)
753 		return -ENOMEM;
754 
755 	evsel->id = zalloc(ncpus * nthreads * sizeof(u64));
756 	if (evsel->id == NULL) {
757 		xyarray__delete(evsel->sample_id);
758 		evsel->sample_id = NULL;
759 		return -ENOMEM;
760 	}
761 
762 	return 0;
763 }
764 
765 void perf_evsel__reset_counts(struct perf_evsel *evsel, int ncpus)
766 {
767 	memset(evsel->counts, 0, (sizeof(*evsel->counts) +
768 				 (ncpus * sizeof(struct perf_counts_values))));
769 }
770 
771 int perf_evsel__alloc_counts(struct perf_evsel *evsel, int ncpus)
772 {
773 	evsel->counts = zalloc((sizeof(*evsel->counts) +
774 				(ncpus * sizeof(struct perf_counts_values))));
775 	return evsel->counts != NULL ? 0 : -ENOMEM;
776 }
777 
778 void perf_evsel__free_fd(struct perf_evsel *evsel)
779 {
780 	xyarray__delete(evsel->fd);
781 	evsel->fd = NULL;
782 }
783 
784 void perf_evsel__free_id(struct perf_evsel *evsel)
785 {
786 	xyarray__delete(evsel->sample_id);
787 	evsel->sample_id = NULL;
788 	free(evsel->id);
789 	evsel->id = NULL;
790 }
791 
792 void perf_evsel__close_fd(struct perf_evsel *evsel, int ncpus, int nthreads)
793 {
794 	int cpu, thread;
795 
796 	for (cpu = 0; cpu < ncpus; cpu++)
797 		for (thread = 0; thread < nthreads; ++thread) {
798 			close(FD(evsel, cpu, thread));
799 			FD(evsel, cpu, thread) = -1;
800 		}
801 }
802 
803 void perf_evsel__free_counts(struct perf_evsel *evsel)
804 {
805 	free(evsel->counts);
806 }
807 
808 void perf_evsel__exit(struct perf_evsel *evsel)
809 {
810 	assert(list_empty(&evsel->node));
811 	perf_evsel__free_fd(evsel);
812 	perf_evsel__free_id(evsel);
813 }
814 
815 void perf_evsel__delete(struct perf_evsel *evsel)
816 {
817 	perf_evsel__exit(evsel);
818 	close_cgroup(evsel->cgrp);
819 	free(evsel->group_name);
820 	if (evsel->tp_format)
821 		pevent_free_format(evsel->tp_format);
822 	free(evsel->name);
823 	free(evsel);
824 }
825 
826 static inline void compute_deltas(struct perf_evsel *evsel,
827 				  int cpu,
828 				  struct perf_counts_values *count)
829 {
830 	struct perf_counts_values tmp;
831 
832 	if (!evsel->prev_raw_counts)
833 		return;
834 
835 	if (cpu == -1) {
836 		tmp = evsel->prev_raw_counts->aggr;
837 		evsel->prev_raw_counts->aggr = *count;
838 	} else {
839 		tmp = evsel->prev_raw_counts->cpu[cpu];
840 		evsel->prev_raw_counts->cpu[cpu] = *count;
841 	}
842 
843 	count->val = count->val - tmp.val;
844 	count->ena = count->ena - tmp.ena;
845 	count->run = count->run - tmp.run;
846 }
847 
848 int __perf_evsel__read_on_cpu(struct perf_evsel *evsel,
849 			      int cpu, int thread, bool scale)
850 {
851 	struct perf_counts_values count;
852 	size_t nv = scale ? 3 : 1;
853 
854 	if (FD(evsel, cpu, thread) < 0)
855 		return -EINVAL;
856 
857 	if (evsel->counts == NULL && perf_evsel__alloc_counts(evsel, cpu + 1) < 0)
858 		return -ENOMEM;
859 
860 	if (readn(FD(evsel, cpu, thread), &count, nv * sizeof(u64)) < 0)
861 		return -errno;
862 
863 	compute_deltas(evsel, cpu, &count);
864 
865 	if (scale) {
866 		if (count.run == 0)
867 			count.val = 0;
868 		else if (count.run < count.ena)
869 			count.val = (u64)((double)count.val * count.ena / count.run + 0.5);
870 	} else
871 		count.ena = count.run = 0;
872 
873 	evsel->counts->cpu[cpu] = count;
874 	return 0;
875 }
876 
877 int __perf_evsel__read(struct perf_evsel *evsel,
878 		       int ncpus, int nthreads, bool scale)
879 {
880 	size_t nv = scale ? 3 : 1;
881 	int cpu, thread;
882 	struct perf_counts_values *aggr = &evsel->counts->aggr, count;
883 
884 	aggr->val = aggr->ena = aggr->run = 0;
885 
886 	for (cpu = 0; cpu < ncpus; cpu++) {
887 		for (thread = 0; thread < nthreads; thread++) {
888 			if (FD(evsel, cpu, thread) < 0)
889 				continue;
890 
891 			if (readn(FD(evsel, cpu, thread),
892 				  &count, nv * sizeof(u64)) < 0)
893 				return -errno;
894 
895 			aggr->val += count.val;
896 			if (scale) {
897 				aggr->ena += count.ena;
898 				aggr->run += count.run;
899 			}
900 		}
901 	}
902 
903 	compute_deltas(evsel, -1, aggr);
904 
905 	evsel->counts->scaled = 0;
906 	if (scale) {
907 		if (aggr->run == 0) {
908 			evsel->counts->scaled = -1;
909 			aggr->val = 0;
910 			return 0;
911 		}
912 
913 		if (aggr->run < aggr->ena) {
914 			evsel->counts->scaled = 1;
915 			aggr->val = (u64)((double)aggr->val * aggr->ena / aggr->run + 0.5);
916 		}
917 	} else
918 		aggr->ena = aggr->run = 0;
919 
920 	return 0;
921 }
922 
923 static int get_group_fd(struct perf_evsel *evsel, int cpu, int thread)
924 {
925 	struct perf_evsel *leader = evsel->leader;
926 	int fd;
927 
928 	if (perf_evsel__is_group_leader(evsel))
929 		return -1;
930 
931 	/*
932 	 * Leader must be already processed/open,
933 	 * if not it's a bug.
934 	 */
935 	BUG_ON(!leader->fd);
936 
937 	fd = FD(leader, cpu, thread);
938 	BUG_ON(fd == -1);
939 
940 	return fd;
941 }
942 
943 #define __PRINT_ATTR(fmt, cast, field)  \
944 	fprintf(fp, "  %-19s "fmt"\n", #field, cast attr->field)
945 
946 #define PRINT_ATTR_U32(field)  __PRINT_ATTR("%u" , , field)
947 #define PRINT_ATTR_X32(field)  __PRINT_ATTR("%#x", , field)
948 #define PRINT_ATTR_U64(field)  __PRINT_ATTR("%" PRIu64, (uint64_t), field)
949 #define PRINT_ATTR_X64(field)  __PRINT_ATTR("%#"PRIx64, (uint64_t), field)
950 
951 #define PRINT_ATTR2N(name1, field1, name2, field2)	\
952 	fprintf(fp, "  %-19s %u    %-19s %u\n",		\
953 	name1, attr->field1, name2, attr->field2)
954 
955 #define PRINT_ATTR2(field1, field2) \
956 	PRINT_ATTR2N(#field1, field1, #field2, field2)
957 
958 static size_t perf_event_attr__fprintf(struct perf_event_attr *attr, FILE *fp)
959 {
960 	size_t ret = 0;
961 
962 	ret += fprintf(fp, "%.60s\n", graph_dotted_line);
963 	ret += fprintf(fp, "perf_event_attr:\n");
964 
965 	ret += PRINT_ATTR_U32(type);
966 	ret += PRINT_ATTR_U32(size);
967 	ret += PRINT_ATTR_X64(config);
968 	ret += PRINT_ATTR_U64(sample_period);
969 	ret += PRINT_ATTR_U64(sample_freq);
970 	ret += PRINT_ATTR_X64(sample_type);
971 	ret += PRINT_ATTR_X64(read_format);
972 
973 	ret += PRINT_ATTR2(disabled, inherit);
974 	ret += PRINT_ATTR2(pinned, exclusive);
975 	ret += PRINT_ATTR2(exclude_user, exclude_kernel);
976 	ret += PRINT_ATTR2(exclude_hv, exclude_idle);
977 	ret += PRINT_ATTR2(mmap, comm);
978 	ret += PRINT_ATTR2(freq, inherit_stat);
979 	ret += PRINT_ATTR2(enable_on_exec, task);
980 	ret += PRINT_ATTR2(watermark, precise_ip);
981 	ret += PRINT_ATTR2(mmap_data, sample_id_all);
982 	ret += PRINT_ATTR2(exclude_host, exclude_guest);
983 	ret += PRINT_ATTR2N("excl.callchain_kern", exclude_callchain_kernel,
984 			    "excl.callchain_user", exclude_callchain_user);
985 
986 	ret += PRINT_ATTR_U32(wakeup_events);
987 	ret += PRINT_ATTR_U32(wakeup_watermark);
988 	ret += PRINT_ATTR_X32(bp_type);
989 	ret += PRINT_ATTR_X64(bp_addr);
990 	ret += PRINT_ATTR_X64(config1);
991 	ret += PRINT_ATTR_U64(bp_len);
992 	ret += PRINT_ATTR_X64(config2);
993 	ret += PRINT_ATTR_X64(branch_sample_type);
994 	ret += PRINT_ATTR_X64(sample_regs_user);
995 	ret += PRINT_ATTR_U32(sample_stack_user);
996 
997 	ret += fprintf(fp, "%.60s\n", graph_dotted_line);
998 
999 	return ret;
1000 }
1001 
1002 static int __perf_evsel__open(struct perf_evsel *evsel, struct cpu_map *cpus,
1003 			      struct thread_map *threads)
1004 {
1005 	int cpu, thread;
1006 	unsigned long flags = 0;
1007 	int pid = -1, err;
1008 	enum { NO_CHANGE, SET_TO_MAX, INCREASED_MAX } set_rlimit = NO_CHANGE;
1009 
1010 	if (evsel->fd == NULL &&
1011 	    perf_evsel__alloc_fd(evsel, cpus->nr, threads->nr) < 0)
1012 		return -ENOMEM;
1013 
1014 	if (evsel->cgrp) {
1015 		flags = PERF_FLAG_PID_CGROUP;
1016 		pid = evsel->cgrp->fd;
1017 	}
1018 
1019 fallback_missing_features:
1020 	if (perf_missing_features.mmap2)
1021 		evsel->attr.mmap2 = 0;
1022 	if (perf_missing_features.exclude_guest)
1023 		evsel->attr.exclude_guest = evsel->attr.exclude_host = 0;
1024 retry_sample_id:
1025 	if (perf_missing_features.sample_id_all)
1026 		evsel->attr.sample_id_all = 0;
1027 
1028 	if (verbose >= 2)
1029 		perf_event_attr__fprintf(&evsel->attr, stderr);
1030 
1031 	for (cpu = 0; cpu < cpus->nr; cpu++) {
1032 
1033 		for (thread = 0; thread < threads->nr; thread++) {
1034 			int group_fd;
1035 
1036 			if (!evsel->cgrp)
1037 				pid = threads->map[thread];
1038 
1039 			group_fd = get_group_fd(evsel, cpu, thread);
1040 retry_open:
1041 			pr_debug2("perf_event_open: pid %d  cpu %d  group_fd %d  flags %#lx\n",
1042 				  pid, cpus->map[cpu], group_fd, flags);
1043 
1044 			FD(evsel, cpu, thread) = sys_perf_event_open(&evsel->attr,
1045 								     pid,
1046 								     cpus->map[cpu],
1047 								     group_fd, flags);
1048 			if (FD(evsel, cpu, thread) < 0) {
1049 				err = -errno;
1050 				goto try_fallback;
1051 			}
1052 			set_rlimit = NO_CHANGE;
1053 		}
1054 	}
1055 
1056 	return 0;
1057 
1058 try_fallback:
1059 	/*
1060 	 * perf stat needs between 5 and 22 fds per CPU. When we run out
1061 	 * of them try to increase the limits.
1062 	 */
1063 	if (err == -EMFILE && set_rlimit < INCREASED_MAX) {
1064 		struct rlimit l;
1065 		int old_errno = errno;
1066 
1067 		if (getrlimit(RLIMIT_NOFILE, &l) == 0) {
1068 			if (set_rlimit == NO_CHANGE)
1069 				l.rlim_cur = l.rlim_max;
1070 			else {
1071 				l.rlim_cur = l.rlim_max + 1000;
1072 				l.rlim_max = l.rlim_cur;
1073 			}
1074 			if (setrlimit(RLIMIT_NOFILE, &l) == 0) {
1075 				set_rlimit++;
1076 				errno = old_errno;
1077 				goto retry_open;
1078 			}
1079 		}
1080 		errno = old_errno;
1081 	}
1082 
1083 	if (err != -EINVAL || cpu > 0 || thread > 0)
1084 		goto out_close;
1085 
1086 	if (!perf_missing_features.mmap2 && evsel->attr.mmap2) {
1087 		perf_missing_features.mmap2 = true;
1088 		goto fallback_missing_features;
1089 	} else if (!perf_missing_features.exclude_guest &&
1090 		   (evsel->attr.exclude_guest || evsel->attr.exclude_host)) {
1091 		perf_missing_features.exclude_guest = true;
1092 		goto fallback_missing_features;
1093 	} else if (!perf_missing_features.sample_id_all) {
1094 		perf_missing_features.sample_id_all = true;
1095 		goto retry_sample_id;
1096 	}
1097 
1098 out_close:
1099 	do {
1100 		while (--thread >= 0) {
1101 			close(FD(evsel, cpu, thread));
1102 			FD(evsel, cpu, thread) = -1;
1103 		}
1104 		thread = threads->nr;
1105 	} while (--cpu >= 0);
1106 	return err;
1107 }
1108 
1109 void perf_evsel__close(struct perf_evsel *evsel, int ncpus, int nthreads)
1110 {
1111 	if (evsel->fd == NULL)
1112 		return;
1113 
1114 	perf_evsel__close_fd(evsel, ncpus, nthreads);
1115 	perf_evsel__free_fd(evsel);
1116 	evsel->fd = NULL;
1117 }
1118 
1119 static struct {
1120 	struct cpu_map map;
1121 	int cpus[1];
1122 } empty_cpu_map = {
1123 	.map.nr	= 1,
1124 	.cpus	= { -1, },
1125 };
1126 
1127 static struct {
1128 	struct thread_map map;
1129 	int threads[1];
1130 } empty_thread_map = {
1131 	.map.nr	 = 1,
1132 	.threads = { -1, },
1133 };
1134 
1135 int perf_evsel__open(struct perf_evsel *evsel, struct cpu_map *cpus,
1136 		     struct thread_map *threads)
1137 {
1138 	if (cpus == NULL) {
1139 		/* Work around old compiler warnings about strict aliasing */
1140 		cpus = &empty_cpu_map.map;
1141 	}
1142 
1143 	if (threads == NULL)
1144 		threads = &empty_thread_map.map;
1145 
1146 	return __perf_evsel__open(evsel, cpus, threads);
1147 }
1148 
1149 int perf_evsel__open_per_cpu(struct perf_evsel *evsel,
1150 			     struct cpu_map *cpus)
1151 {
1152 	return __perf_evsel__open(evsel, cpus, &empty_thread_map.map);
1153 }
1154 
1155 int perf_evsel__open_per_thread(struct perf_evsel *evsel,
1156 				struct thread_map *threads)
1157 {
1158 	return __perf_evsel__open(evsel, &empty_cpu_map.map, threads);
1159 }
1160 
1161 static int perf_evsel__parse_id_sample(const struct perf_evsel *evsel,
1162 				       const union perf_event *event,
1163 				       struct perf_sample *sample)
1164 {
1165 	u64 type = evsel->attr.sample_type;
1166 	const u64 *array = event->sample.array;
1167 	bool swapped = evsel->needs_swap;
1168 	union u64_swap u;
1169 
1170 	array += ((event->header.size -
1171 		   sizeof(event->header)) / sizeof(u64)) - 1;
1172 
1173 	if (type & PERF_SAMPLE_IDENTIFIER) {
1174 		sample->id = *array;
1175 		array--;
1176 	}
1177 
1178 	if (type & PERF_SAMPLE_CPU) {
1179 		u.val64 = *array;
1180 		if (swapped) {
1181 			/* undo swap of u64, then swap on individual u32s */
1182 			u.val64 = bswap_64(u.val64);
1183 			u.val32[0] = bswap_32(u.val32[0]);
1184 		}
1185 
1186 		sample->cpu = u.val32[0];
1187 		array--;
1188 	}
1189 
1190 	if (type & PERF_SAMPLE_STREAM_ID) {
1191 		sample->stream_id = *array;
1192 		array--;
1193 	}
1194 
1195 	if (type & PERF_SAMPLE_ID) {
1196 		sample->id = *array;
1197 		array--;
1198 	}
1199 
1200 	if (type & PERF_SAMPLE_TIME) {
1201 		sample->time = *array;
1202 		array--;
1203 	}
1204 
1205 	if (type & PERF_SAMPLE_TID) {
1206 		u.val64 = *array;
1207 		if (swapped) {
1208 			/* undo swap of u64, then swap on individual u32s */
1209 			u.val64 = bswap_64(u.val64);
1210 			u.val32[0] = bswap_32(u.val32[0]);
1211 			u.val32[1] = bswap_32(u.val32[1]);
1212 		}
1213 
1214 		sample->pid = u.val32[0];
1215 		sample->tid = u.val32[1];
1216 	}
1217 
1218 	return 0;
1219 }
1220 
1221 static inline bool overflow(const void *endp, u16 max_size, const void *offset,
1222 			    u64 size)
1223 {
1224 	return size > max_size || offset + size > endp;
1225 }
1226 
1227 #define OVERFLOW_CHECK(offset, size, max_size)				\
1228 	do {								\
1229 		if (overflow(endp, (max_size), (offset), (size)))	\
1230 			return -EFAULT;					\
1231 	} while (0)
1232 
1233 #define OVERFLOW_CHECK_u64(offset) \
1234 	OVERFLOW_CHECK(offset, sizeof(u64), sizeof(u64))
1235 
1236 int perf_evsel__parse_sample(struct perf_evsel *evsel, union perf_event *event,
1237 			     struct perf_sample *data)
1238 {
1239 	u64 type = evsel->attr.sample_type;
1240 	bool swapped = evsel->needs_swap;
1241 	const u64 *array;
1242 	u16 max_size = event->header.size;
1243 	const void *endp = (void *)event + max_size;
1244 	u64 sz;
1245 
1246 	/*
1247 	 * used for cross-endian analysis. See git commit 65014ab3
1248 	 * for why this goofiness is needed.
1249 	 */
1250 	union u64_swap u;
1251 
1252 	memset(data, 0, sizeof(*data));
1253 	data->cpu = data->pid = data->tid = -1;
1254 	data->stream_id = data->id = data->time = -1ULL;
1255 	data->period = 1;
1256 	data->weight = 0;
1257 
1258 	if (event->header.type != PERF_RECORD_SAMPLE) {
1259 		if (!evsel->attr.sample_id_all)
1260 			return 0;
1261 		return perf_evsel__parse_id_sample(evsel, event, data);
1262 	}
1263 
1264 	array = event->sample.array;
1265 
1266 	/*
1267 	 * The evsel's sample_size is based on PERF_SAMPLE_MASK which includes
1268 	 * up to PERF_SAMPLE_PERIOD.  After that overflow() must be used to
1269 	 * check the format does not go past the end of the event.
1270 	 */
1271 	if (evsel->sample_size + sizeof(event->header) > event->header.size)
1272 		return -EFAULT;
1273 
1274 	data->id = -1ULL;
1275 	if (type & PERF_SAMPLE_IDENTIFIER) {
1276 		data->id = *array;
1277 		array++;
1278 	}
1279 
1280 	if (type & PERF_SAMPLE_IP) {
1281 		data->ip = *array;
1282 		array++;
1283 	}
1284 
1285 	if (type & PERF_SAMPLE_TID) {
1286 		u.val64 = *array;
1287 		if (swapped) {
1288 			/* undo swap of u64, then swap on individual u32s */
1289 			u.val64 = bswap_64(u.val64);
1290 			u.val32[0] = bswap_32(u.val32[0]);
1291 			u.val32[1] = bswap_32(u.val32[1]);
1292 		}
1293 
1294 		data->pid = u.val32[0];
1295 		data->tid = u.val32[1];
1296 		array++;
1297 	}
1298 
1299 	if (type & PERF_SAMPLE_TIME) {
1300 		data->time = *array;
1301 		array++;
1302 	}
1303 
1304 	data->addr = 0;
1305 	if (type & PERF_SAMPLE_ADDR) {
1306 		data->addr = *array;
1307 		array++;
1308 	}
1309 
1310 	if (type & PERF_SAMPLE_ID) {
1311 		data->id = *array;
1312 		array++;
1313 	}
1314 
1315 	if (type & PERF_SAMPLE_STREAM_ID) {
1316 		data->stream_id = *array;
1317 		array++;
1318 	}
1319 
1320 	if (type & PERF_SAMPLE_CPU) {
1321 
1322 		u.val64 = *array;
1323 		if (swapped) {
1324 			/* undo swap of u64, then swap on individual u32s */
1325 			u.val64 = bswap_64(u.val64);
1326 			u.val32[0] = bswap_32(u.val32[0]);
1327 		}
1328 
1329 		data->cpu = u.val32[0];
1330 		array++;
1331 	}
1332 
1333 	if (type & PERF_SAMPLE_PERIOD) {
1334 		data->period = *array;
1335 		array++;
1336 	}
1337 
1338 	if (type & PERF_SAMPLE_READ) {
1339 		u64 read_format = evsel->attr.read_format;
1340 
1341 		OVERFLOW_CHECK_u64(array);
1342 		if (read_format & PERF_FORMAT_GROUP)
1343 			data->read.group.nr = *array;
1344 		else
1345 			data->read.one.value = *array;
1346 
1347 		array++;
1348 
1349 		if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) {
1350 			OVERFLOW_CHECK_u64(array);
1351 			data->read.time_enabled = *array;
1352 			array++;
1353 		}
1354 
1355 		if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) {
1356 			OVERFLOW_CHECK_u64(array);
1357 			data->read.time_running = *array;
1358 			array++;
1359 		}
1360 
1361 		/* PERF_FORMAT_ID is forced for PERF_SAMPLE_READ */
1362 		if (read_format & PERF_FORMAT_GROUP) {
1363 			const u64 max_group_nr = UINT64_MAX /
1364 					sizeof(struct sample_read_value);
1365 
1366 			if (data->read.group.nr > max_group_nr)
1367 				return -EFAULT;
1368 			sz = data->read.group.nr *
1369 			     sizeof(struct sample_read_value);
1370 			OVERFLOW_CHECK(array, sz, max_size);
1371 			data->read.group.values =
1372 					(struct sample_read_value *)array;
1373 			array = (void *)array + sz;
1374 		} else {
1375 			OVERFLOW_CHECK_u64(array);
1376 			data->read.one.id = *array;
1377 			array++;
1378 		}
1379 	}
1380 
1381 	if (type & PERF_SAMPLE_CALLCHAIN) {
1382 		const u64 max_callchain_nr = UINT64_MAX / sizeof(u64);
1383 
1384 		OVERFLOW_CHECK_u64(array);
1385 		data->callchain = (struct ip_callchain *)array++;
1386 		if (data->callchain->nr > max_callchain_nr)
1387 			return -EFAULT;
1388 		sz = data->callchain->nr * sizeof(u64);
1389 		OVERFLOW_CHECK(array, sz, max_size);
1390 		array = (void *)array + sz;
1391 	}
1392 
1393 	if (type & PERF_SAMPLE_RAW) {
1394 		OVERFLOW_CHECK_u64(array);
1395 		u.val64 = *array;
1396 		if (WARN_ONCE(swapped,
1397 			      "Endianness of raw data not corrected!\n")) {
1398 			/* undo swap of u64, then swap on individual u32s */
1399 			u.val64 = bswap_64(u.val64);
1400 			u.val32[0] = bswap_32(u.val32[0]);
1401 			u.val32[1] = bswap_32(u.val32[1]);
1402 		}
1403 		data->raw_size = u.val32[0];
1404 		array = (void *)array + sizeof(u32);
1405 
1406 		OVERFLOW_CHECK(array, data->raw_size, max_size);
1407 		data->raw_data = (void *)array;
1408 		array = (void *)array + data->raw_size;
1409 	}
1410 
1411 	if (type & PERF_SAMPLE_BRANCH_STACK) {
1412 		const u64 max_branch_nr = UINT64_MAX /
1413 					  sizeof(struct branch_entry);
1414 
1415 		OVERFLOW_CHECK_u64(array);
1416 		data->branch_stack = (struct branch_stack *)array++;
1417 
1418 		if (data->branch_stack->nr > max_branch_nr)
1419 			return -EFAULT;
1420 		sz = data->branch_stack->nr * sizeof(struct branch_entry);
1421 		OVERFLOW_CHECK(array, sz, max_size);
1422 		array = (void *)array + sz;
1423 	}
1424 
1425 	if (type & PERF_SAMPLE_REGS_USER) {
1426 		OVERFLOW_CHECK_u64(array);
1427 		data->user_regs.abi = *array;
1428 		array++;
1429 
1430 		if (data->user_regs.abi) {
1431 			u64 regs_user = evsel->attr.sample_regs_user;
1432 
1433 			sz = hweight_long(regs_user) * sizeof(u64);
1434 			OVERFLOW_CHECK(array, sz, max_size);
1435 			data->user_regs.regs = (u64 *)array;
1436 			array = (void *)array + sz;
1437 		}
1438 	}
1439 
1440 	if (type & PERF_SAMPLE_STACK_USER) {
1441 		OVERFLOW_CHECK_u64(array);
1442 		sz = *array++;
1443 
1444 		data->user_stack.offset = ((char *)(array - 1)
1445 					  - (char *) event);
1446 
1447 		if (!sz) {
1448 			data->user_stack.size = 0;
1449 		} else {
1450 			OVERFLOW_CHECK(array, sz, max_size);
1451 			data->user_stack.data = (char *)array;
1452 			array = (void *)array + sz;
1453 			OVERFLOW_CHECK_u64(array);
1454 			data->user_stack.size = *array++;
1455 		}
1456 	}
1457 
1458 	data->weight = 0;
1459 	if (type & PERF_SAMPLE_WEIGHT) {
1460 		OVERFLOW_CHECK_u64(array);
1461 		data->weight = *array;
1462 		array++;
1463 	}
1464 
1465 	data->data_src = PERF_MEM_DATA_SRC_NONE;
1466 	if (type & PERF_SAMPLE_DATA_SRC) {
1467 		OVERFLOW_CHECK_u64(array);
1468 		data->data_src = *array;
1469 		array++;
1470 	}
1471 
1472 	return 0;
1473 }
1474 
1475 size_t perf_event__sample_event_size(const struct perf_sample *sample, u64 type,
1476 				     u64 sample_regs_user, u64 read_format)
1477 {
1478 	size_t sz, result = sizeof(struct sample_event);
1479 
1480 	if (type & PERF_SAMPLE_IDENTIFIER)
1481 		result += sizeof(u64);
1482 
1483 	if (type & PERF_SAMPLE_IP)
1484 		result += sizeof(u64);
1485 
1486 	if (type & PERF_SAMPLE_TID)
1487 		result += sizeof(u64);
1488 
1489 	if (type & PERF_SAMPLE_TIME)
1490 		result += sizeof(u64);
1491 
1492 	if (type & PERF_SAMPLE_ADDR)
1493 		result += sizeof(u64);
1494 
1495 	if (type & PERF_SAMPLE_ID)
1496 		result += sizeof(u64);
1497 
1498 	if (type & PERF_SAMPLE_STREAM_ID)
1499 		result += sizeof(u64);
1500 
1501 	if (type & PERF_SAMPLE_CPU)
1502 		result += sizeof(u64);
1503 
1504 	if (type & PERF_SAMPLE_PERIOD)
1505 		result += sizeof(u64);
1506 
1507 	if (type & PERF_SAMPLE_READ) {
1508 		result += sizeof(u64);
1509 		if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED)
1510 			result += sizeof(u64);
1511 		if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING)
1512 			result += sizeof(u64);
1513 		/* PERF_FORMAT_ID is forced for PERF_SAMPLE_READ */
1514 		if (read_format & PERF_FORMAT_GROUP) {
1515 			sz = sample->read.group.nr *
1516 			     sizeof(struct sample_read_value);
1517 			result += sz;
1518 		} else {
1519 			result += sizeof(u64);
1520 		}
1521 	}
1522 
1523 	if (type & PERF_SAMPLE_CALLCHAIN) {
1524 		sz = (sample->callchain->nr + 1) * sizeof(u64);
1525 		result += sz;
1526 	}
1527 
1528 	if (type & PERF_SAMPLE_RAW) {
1529 		result += sizeof(u32);
1530 		result += sample->raw_size;
1531 	}
1532 
1533 	if (type & PERF_SAMPLE_BRANCH_STACK) {
1534 		sz = sample->branch_stack->nr * sizeof(struct branch_entry);
1535 		sz += sizeof(u64);
1536 		result += sz;
1537 	}
1538 
1539 	if (type & PERF_SAMPLE_REGS_USER) {
1540 		if (sample->user_regs.abi) {
1541 			result += sizeof(u64);
1542 			sz = hweight_long(sample_regs_user) * sizeof(u64);
1543 			result += sz;
1544 		} else {
1545 			result += sizeof(u64);
1546 		}
1547 	}
1548 
1549 	if (type & PERF_SAMPLE_STACK_USER) {
1550 		sz = sample->user_stack.size;
1551 		result += sizeof(u64);
1552 		if (sz) {
1553 			result += sz;
1554 			result += sizeof(u64);
1555 		}
1556 	}
1557 
1558 	if (type & PERF_SAMPLE_WEIGHT)
1559 		result += sizeof(u64);
1560 
1561 	if (type & PERF_SAMPLE_DATA_SRC)
1562 		result += sizeof(u64);
1563 
1564 	return result;
1565 }
1566 
1567 int perf_event__synthesize_sample(union perf_event *event, u64 type,
1568 				  u64 sample_regs_user, u64 read_format,
1569 				  const struct perf_sample *sample,
1570 				  bool swapped)
1571 {
1572 	u64 *array;
1573 	size_t sz;
1574 	/*
1575 	 * used for cross-endian analysis. See git commit 65014ab3
1576 	 * for why this goofiness is needed.
1577 	 */
1578 	union u64_swap u;
1579 
1580 	array = event->sample.array;
1581 
1582 	if (type & PERF_SAMPLE_IDENTIFIER) {
1583 		*array = sample->id;
1584 		array++;
1585 	}
1586 
1587 	if (type & PERF_SAMPLE_IP) {
1588 		*array = sample->ip;
1589 		array++;
1590 	}
1591 
1592 	if (type & PERF_SAMPLE_TID) {
1593 		u.val32[0] = sample->pid;
1594 		u.val32[1] = sample->tid;
1595 		if (swapped) {
1596 			/*
1597 			 * Inverse of what is done in perf_evsel__parse_sample
1598 			 */
1599 			u.val32[0] = bswap_32(u.val32[0]);
1600 			u.val32[1] = bswap_32(u.val32[1]);
1601 			u.val64 = bswap_64(u.val64);
1602 		}
1603 
1604 		*array = u.val64;
1605 		array++;
1606 	}
1607 
1608 	if (type & PERF_SAMPLE_TIME) {
1609 		*array = sample->time;
1610 		array++;
1611 	}
1612 
1613 	if (type & PERF_SAMPLE_ADDR) {
1614 		*array = sample->addr;
1615 		array++;
1616 	}
1617 
1618 	if (type & PERF_SAMPLE_ID) {
1619 		*array = sample->id;
1620 		array++;
1621 	}
1622 
1623 	if (type & PERF_SAMPLE_STREAM_ID) {
1624 		*array = sample->stream_id;
1625 		array++;
1626 	}
1627 
1628 	if (type & PERF_SAMPLE_CPU) {
1629 		u.val32[0] = sample->cpu;
1630 		if (swapped) {
1631 			/*
1632 			 * Inverse of what is done in perf_evsel__parse_sample
1633 			 */
1634 			u.val32[0] = bswap_32(u.val32[0]);
1635 			u.val64 = bswap_64(u.val64);
1636 		}
1637 		*array = u.val64;
1638 		array++;
1639 	}
1640 
1641 	if (type & PERF_SAMPLE_PERIOD) {
1642 		*array = sample->period;
1643 		array++;
1644 	}
1645 
1646 	if (type & PERF_SAMPLE_READ) {
1647 		if (read_format & PERF_FORMAT_GROUP)
1648 			*array = sample->read.group.nr;
1649 		else
1650 			*array = sample->read.one.value;
1651 		array++;
1652 
1653 		if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) {
1654 			*array = sample->read.time_enabled;
1655 			array++;
1656 		}
1657 
1658 		if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) {
1659 			*array = sample->read.time_running;
1660 			array++;
1661 		}
1662 
1663 		/* PERF_FORMAT_ID is forced for PERF_SAMPLE_READ */
1664 		if (read_format & PERF_FORMAT_GROUP) {
1665 			sz = sample->read.group.nr *
1666 			     sizeof(struct sample_read_value);
1667 			memcpy(array, sample->read.group.values, sz);
1668 			array = (void *)array + sz;
1669 		} else {
1670 			*array = sample->read.one.id;
1671 			array++;
1672 		}
1673 	}
1674 
1675 	if (type & PERF_SAMPLE_CALLCHAIN) {
1676 		sz = (sample->callchain->nr + 1) * sizeof(u64);
1677 		memcpy(array, sample->callchain, sz);
1678 		array = (void *)array + sz;
1679 	}
1680 
1681 	if (type & PERF_SAMPLE_RAW) {
1682 		u.val32[0] = sample->raw_size;
1683 		if (WARN_ONCE(swapped,
1684 			      "Endianness of raw data not corrected!\n")) {
1685 			/*
1686 			 * Inverse of what is done in perf_evsel__parse_sample
1687 			 */
1688 			u.val32[0] = bswap_32(u.val32[0]);
1689 			u.val32[1] = bswap_32(u.val32[1]);
1690 			u.val64 = bswap_64(u.val64);
1691 		}
1692 		*array = u.val64;
1693 		array = (void *)array + sizeof(u32);
1694 
1695 		memcpy(array, sample->raw_data, sample->raw_size);
1696 		array = (void *)array + sample->raw_size;
1697 	}
1698 
1699 	if (type & PERF_SAMPLE_BRANCH_STACK) {
1700 		sz = sample->branch_stack->nr * sizeof(struct branch_entry);
1701 		sz += sizeof(u64);
1702 		memcpy(array, sample->branch_stack, sz);
1703 		array = (void *)array + sz;
1704 	}
1705 
1706 	if (type & PERF_SAMPLE_REGS_USER) {
1707 		if (sample->user_regs.abi) {
1708 			*array++ = sample->user_regs.abi;
1709 			sz = hweight_long(sample_regs_user) * sizeof(u64);
1710 			memcpy(array, sample->user_regs.regs, sz);
1711 			array = (void *)array + sz;
1712 		} else {
1713 			*array++ = 0;
1714 		}
1715 	}
1716 
1717 	if (type & PERF_SAMPLE_STACK_USER) {
1718 		sz = sample->user_stack.size;
1719 		*array++ = sz;
1720 		if (sz) {
1721 			memcpy(array, sample->user_stack.data, sz);
1722 			array = (void *)array + sz;
1723 			*array++ = sz;
1724 		}
1725 	}
1726 
1727 	if (type & PERF_SAMPLE_WEIGHT) {
1728 		*array = sample->weight;
1729 		array++;
1730 	}
1731 
1732 	if (type & PERF_SAMPLE_DATA_SRC) {
1733 		*array = sample->data_src;
1734 		array++;
1735 	}
1736 
1737 	return 0;
1738 }
1739 
1740 struct format_field *perf_evsel__field(struct perf_evsel *evsel, const char *name)
1741 {
1742 	return pevent_find_field(evsel->tp_format, name);
1743 }
1744 
1745 void *perf_evsel__rawptr(struct perf_evsel *evsel, struct perf_sample *sample,
1746 			 const char *name)
1747 {
1748 	struct format_field *field = perf_evsel__field(evsel, name);
1749 	int offset;
1750 
1751 	if (!field)
1752 		return NULL;
1753 
1754 	offset = field->offset;
1755 
1756 	if (field->flags & FIELD_IS_DYNAMIC) {
1757 		offset = *(int *)(sample->raw_data + field->offset);
1758 		offset &= 0xffff;
1759 	}
1760 
1761 	return sample->raw_data + offset;
1762 }
1763 
1764 u64 perf_evsel__intval(struct perf_evsel *evsel, struct perf_sample *sample,
1765 		       const char *name)
1766 {
1767 	struct format_field *field = perf_evsel__field(evsel, name);
1768 	void *ptr;
1769 	u64 value;
1770 
1771 	if (!field)
1772 		return 0;
1773 
1774 	ptr = sample->raw_data + field->offset;
1775 
1776 	switch (field->size) {
1777 	case 1:
1778 		return *(u8 *)ptr;
1779 	case 2:
1780 		value = *(u16 *)ptr;
1781 		break;
1782 	case 4:
1783 		value = *(u32 *)ptr;
1784 		break;
1785 	case 8:
1786 		value = *(u64 *)ptr;
1787 		break;
1788 	default:
1789 		return 0;
1790 	}
1791 
1792 	if (!evsel->needs_swap)
1793 		return value;
1794 
1795 	switch (field->size) {
1796 	case 2:
1797 		return bswap_16(value);
1798 	case 4:
1799 		return bswap_32(value);
1800 	case 8:
1801 		return bswap_64(value);
1802 	default:
1803 		return 0;
1804 	}
1805 
1806 	return 0;
1807 }
1808 
1809 static int comma_fprintf(FILE *fp, bool *first, const char *fmt, ...)
1810 {
1811 	va_list args;
1812 	int ret = 0;
1813 
1814 	if (!*first) {
1815 		ret += fprintf(fp, ",");
1816 	} else {
1817 		ret += fprintf(fp, ":");
1818 		*first = false;
1819 	}
1820 
1821 	va_start(args, fmt);
1822 	ret += vfprintf(fp, fmt, args);
1823 	va_end(args);
1824 	return ret;
1825 }
1826 
1827 static int __if_fprintf(FILE *fp, bool *first, const char *field, u64 value)
1828 {
1829 	if (value == 0)
1830 		return 0;
1831 
1832 	return comma_fprintf(fp, first, " %s: %" PRIu64, field, value);
1833 }
1834 
1835 #define if_print(field) printed += __if_fprintf(fp, &first, #field, evsel->attr.field)
1836 
1837 struct bit_names {
1838 	int bit;
1839 	const char *name;
1840 };
1841 
1842 static int bits__fprintf(FILE *fp, const char *field, u64 value,
1843 			 struct bit_names *bits, bool *first)
1844 {
1845 	int i = 0, printed = comma_fprintf(fp, first, " %s: ", field);
1846 	bool first_bit = true;
1847 
1848 	do {
1849 		if (value & bits[i].bit) {
1850 			printed += fprintf(fp, "%s%s", first_bit ? "" : "|", bits[i].name);
1851 			first_bit = false;
1852 		}
1853 	} while (bits[++i].name != NULL);
1854 
1855 	return printed;
1856 }
1857 
1858 static int sample_type__fprintf(FILE *fp, bool *first, u64 value)
1859 {
1860 #define bit_name(n) { PERF_SAMPLE_##n, #n }
1861 	struct bit_names bits[] = {
1862 		bit_name(IP), bit_name(TID), bit_name(TIME), bit_name(ADDR),
1863 		bit_name(READ), bit_name(CALLCHAIN), bit_name(ID), bit_name(CPU),
1864 		bit_name(PERIOD), bit_name(STREAM_ID), bit_name(RAW),
1865 		bit_name(BRANCH_STACK), bit_name(REGS_USER), bit_name(STACK_USER),
1866 		bit_name(IDENTIFIER),
1867 		{ .name = NULL, }
1868 	};
1869 #undef bit_name
1870 	return bits__fprintf(fp, "sample_type", value, bits, first);
1871 }
1872 
1873 static int read_format__fprintf(FILE *fp, bool *first, u64 value)
1874 {
1875 #define bit_name(n) { PERF_FORMAT_##n, #n }
1876 	struct bit_names bits[] = {
1877 		bit_name(TOTAL_TIME_ENABLED), bit_name(TOTAL_TIME_RUNNING),
1878 		bit_name(ID), bit_name(GROUP),
1879 		{ .name = NULL, }
1880 	};
1881 #undef bit_name
1882 	return bits__fprintf(fp, "read_format", value, bits, first);
1883 }
1884 
1885 int perf_evsel__fprintf(struct perf_evsel *evsel,
1886 			struct perf_attr_details *details, FILE *fp)
1887 {
1888 	bool first = true;
1889 	int printed = 0;
1890 
1891 	if (details->event_group) {
1892 		struct perf_evsel *pos;
1893 
1894 		if (!perf_evsel__is_group_leader(evsel))
1895 			return 0;
1896 
1897 		if (evsel->nr_members > 1)
1898 			printed += fprintf(fp, "%s{", evsel->group_name ?: "");
1899 
1900 		printed += fprintf(fp, "%s", perf_evsel__name(evsel));
1901 		for_each_group_member(pos, evsel)
1902 			printed += fprintf(fp, ",%s", perf_evsel__name(pos));
1903 
1904 		if (evsel->nr_members > 1)
1905 			printed += fprintf(fp, "}");
1906 		goto out;
1907 	}
1908 
1909 	printed += fprintf(fp, "%s", perf_evsel__name(evsel));
1910 
1911 	if (details->verbose || details->freq) {
1912 		printed += comma_fprintf(fp, &first, " sample_freq=%" PRIu64,
1913 					 (u64)evsel->attr.sample_freq);
1914 	}
1915 
1916 	if (details->verbose) {
1917 		if_print(type);
1918 		if_print(config);
1919 		if_print(config1);
1920 		if_print(config2);
1921 		if_print(size);
1922 		printed += sample_type__fprintf(fp, &first, evsel->attr.sample_type);
1923 		if (evsel->attr.read_format)
1924 			printed += read_format__fprintf(fp, &first, evsel->attr.read_format);
1925 		if_print(disabled);
1926 		if_print(inherit);
1927 		if_print(pinned);
1928 		if_print(exclusive);
1929 		if_print(exclude_user);
1930 		if_print(exclude_kernel);
1931 		if_print(exclude_hv);
1932 		if_print(exclude_idle);
1933 		if_print(mmap);
1934 		if_print(mmap2);
1935 		if_print(comm);
1936 		if_print(freq);
1937 		if_print(inherit_stat);
1938 		if_print(enable_on_exec);
1939 		if_print(task);
1940 		if_print(watermark);
1941 		if_print(precise_ip);
1942 		if_print(mmap_data);
1943 		if_print(sample_id_all);
1944 		if_print(exclude_host);
1945 		if_print(exclude_guest);
1946 		if_print(__reserved_1);
1947 		if_print(wakeup_events);
1948 		if_print(bp_type);
1949 		if_print(branch_sample_type);
1950 	}
1951 out:
1952 	fputc('\n', fp);
1953 	return ++printed;
1954 }
1955 
1956 bool perf_evsel__fallback(struct perf_evsel *evsel, int err,
1957 			  char *msg, size_t msgsize)
1958 {
1959 	if ((err == ENOENT || err == ENXIO || err == ENODEV) &&
1960 	    evsel->attr.type   == PERF_TYPE_HARDWARE &&
1961 	    evsel->attr.config == PERF_COUNT_HW_CPU_CYCLES) {
1962 		/*
1963 		 * If it's cycles then fall back to hrtimer based
1964 		 * cpu-clock-tick sw counter, which is always available even if
1965 		 * no PMU support.
1966 		 *
1967 		 * PPC returns ENXIO until 2.6.37 (behavior changed with commit
1968 		 * b0a873e).
1969 		 */
1970 		scnprintf(msg, msgsize, "%s",
1971 "The cycles event is not supported, trying to fall back to cpu-clock-ticks");
1972 
1973 		evsel->attr.type   = PERF_TYPE_SOFTWARE;
1974 		evsel->attr.config = PERF_COUNT_SW_CPU_CLOCK;
1975 
1976 		free(evsel->name);
1977 		evsel->name = NULL;
1978 		return true;
1979 	}
1980 
1981 	return false;
1982 }
1983 
1984 int perf_evsel__open_strerror(struct perf_evsel *evsel,
1985 			      struct perf_target *target,
1986 			      int err, char *msg, size_t size)
1987 {
1988 	switch (err) {
1989 	case EPERM:
1990 	case EACCES:
1991 		return scnprintf(msg, size,
1992 		 "You may not have permission to collect %sstats.\n"
1993 		 "Consider tweaking /proc/sys/kernel/perf_event_paranoid:\n"
1994 		 " -1 - Not paranoid at all\n"
1995 		 "  0 - Disallow raw tracepoint access for unpriv\n"
1996 		 "  1 - Disallow cpu events for unpriv\n"
1997 		 "  2 - Disallow kernel profiling for unpriv",
1998 				 target->system_wide ? "system-wide " : "");
1999 	case ENOENT:
2000 		return scnprintf(msg, size, "The %s event is not supported.",
2001 				 perf_evsel__name(evsel));
2002 	case EMFILE:
2003 		return scnprintf(msg, size, "%s",
2004 			 "Too many events are opened.\n"
2005 			 "Try again after reducing the number of events.");
2006 	case ENODEV:
2007 		if (target->cpu_list)
2008 			return scnprintf(msg, size, "%s",
2009 	 "No such device - did you specify an out-of-range profile CPU?\n");
2010 		break;
2011 	case EOPNOTSUPP:
2012 		if (evsel->attr.precise_ip)
2013 			return scnprintf(msg, size, "%s",
2014 	"\'precise\' request may not be supported. Try removing 'p' modifier.");
2015 #if defined(__i386__) || defined(__x86_64__)
2016 		if (evsel->attr.type == PERF_TYPE_HARDWARE)
2017 			return scnprintf(msg, size, "%s",
2018 	"No hardware sampling interrupt available.\n"
2019 	"No APIC? If so then you can boot the kernel with the \"lapic\" boot parameter to force-enable it.");
2020 #endif
2021 		break;
2022 	default:
2023 		break;
2024 	}
2025 
2026 	return scnprintf(msg, size,
2027 	"The sys_perf_event_open() syscall returned with %d (%s) for event (%s).  \n"
2028 	"/bin/dmesg may provide additional information.\n"
2029 	"No CONFIG_PERF_EVENTS=y kernel support configured?\n",
2030 			 err, strerror(err), perf_evsel__name(evsel));
2031 }
2032