xref: /openbmc/linux/tools/perf/util/evsel.c (revision afc98d90)
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 <api/fs/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 #include "trace-event.h"
27 
28 static struct {
29 	bool sample_id_all;
30 	bool exclude_guest;
31 	bool mmap2;
32 } perf_missing_features;
33 
34 #define FD(e, x, y) (*(int *)xyarray__entry(e->fd, x, y))
35 
36 int __perf_evsel__sample_size(u64 sample_type)
37 {
38 	u64 mask = sample_type & PERF_SAMPLE_MASK;
39 	int size = 0;
40 	int i;
41 
42 	for (i = 0; i < 64; i++) {
43 		if (mask & (1ULL << i))
44 			size++;
45 	}
46 
47 	size *= sizeof(u64);
48 
49 	return size;
50 }
51 
52 /**
53  * __perf_evsel__calc_id_pos - calculate id_pos.
54  * @sample_type: sample type
55  *
56  * This function returns the position of the event id (PERF_SAMPLE_ID or
57  * PERF_SAMPLE_IDENTIFIER) in a sample event i.e. in the array of struct
58  * sample_event.
59  */
60 static int __perf_evsel__calc_id_pos(u64 sample_type)
61 {
62 	int idx = 0;
63 
64 	if (sample_type & PERF_SAMPLE_IDENTIFIER)
65 		return 0;
66 
67 	if (!(sample_type & PERF_SAMPLE_ID))
68 		return -1;
69 
70 	if (sample_type & PERF_SAMPLE_IP)
71 		idx += 1;
72 
73 	if (sample_type & PERF_SAMPLE_TID)
74 		idx += 1;
75 
76 	if (sample_type & PERF_SAMPLE_TIME)
77 		idx += 1;
78 
79 	if (sample_type & PERF_SAMPLE_ADDR)
80 		idx += 1;
81 
82 	return idx;
83 }
84 
85 /**
86  * __perf_evsel__calc_is_pos - calculate is_pos.
87  * @sample_type: sample type
88  *
89  * This function returns the position (counting backwards) of the event id
90  * (PERF_SAMPLE_ID or PERF_SAMPLE_IDENTIFIER) in a non-sample event i.e. if
91  * sample_id_all is used there is an id sample appended to non-sample events.
92  */
93 static int __perf_evsel__calc_is_pos(u64 sample_type)
94 {
95 	int idx = 1;
96 
97 	if (sample_type & PERF_SAMPLE_IDENTIFIER)
98 		return 1;
99 
100 	if (!(sample_type & PERF_SAMPLE_ID))
101 		return -1;
102 
103 	if (sample_type & PERF_SAMPLE_CPU)
104 		idx += 1;
105 
106 	if (sample_type & PERF_SAMPLE_STREAM_ID)
107 		idx += 1;
108 
109 	return idx;
110 }
111 
112 void perf_evsel__calc_id_pos(struct perf_evsel *evsel)
113 {
114 	evsel->id_pos = __perf_evsel__calc_id_pos(evsel->attr.sample_type);
115 	evsel->is_pos = __perf_evsel__calc_is_pos(evsel->attr.sample_type);
116 }
117 
118 void hists__init(struct hists *hists)
119 {
120 	memset(hists, 0, sizeof(*hists));
121 	hists->entries_in_array[0] = hists->entries_in_array[1] = RB_ROOT;
122 	hists->entries_in = &hists->entries_in_array[0];
123 	hists->entries_collapsed = RB_ROOT;
124 	hists->entries = RB_ROOT;
125 	pthread_mutex_init(&hists->lock, NULL);
126 }
127 
128 void __perf_evsel__set_sample_bit(struct perf_evsel *evsel,
129 				  enum perf_event_sample_format bit)
130 {
131 	if (!(evsel->attr.sample_type & bit)) {
132 		evsel->attr.sample_type |= bit;
133 		evsel->sample_size += sizeof(u64);
134 		perf_evsel__calc_id_pos(evsel);
135 	}
136 }
137 
138 void __perf_evsel__reset_sample_bit(struct perf_evsel *evsel,
139 				    enum perf_event_sample_format bit)
140 {
141 	if (evsel->attr.sample_type & bit) {
142 		evsel->attr.sample_type &= ~bit;
143 		evsel->sample_size -= sizeof(u64);
144 		perf_evsel__calc_id_pos(evsel);
145 	}
146 }
147 
148 void perf_evsel__set_sample_id(struct perf_evsel *evsel,
149 			       bool can_sample_identifier)
150 {
151 	if (can_sample_identifier) {
152 		perf_evsel__reset_sample_bit(evsel, ID);
153 		perf_evsel__set_sample_bit(evsel, IDENTIFIER);
154 	} else {
155 		perf_evsel__set_sample_bit(evsel, ID);
156 	}
157 	evsel->attr.read_format |= PERF_FORMAT_ID;
158 }
159 
160 void perf_evsel__init(struct perf_evsel *evsel,
161 		      struct perf_event_attr *attr, int idx)
162 {
163 	evsel->idx	   = idx;
164 	evsel->attr	   = *attr;
165 	evsel->leader	   = evsel;
166 	evsel->unit	   = "";
167 	evsel->scale	   = 1.0;
168 	INIT_LIST_HEAD(&evsel->node);
169 	hists__init(&evsel->hists);
170 	evsel->sample_size = __perf_evsel__sample_size(attr->sample_type);
171 	perf_evsel__calc_id_pos(evsel);
172 }
173 
174 struct perf_evsel *perf_evsel__new_idx(struct perf_event_attr *attr, int idx)
175 {
176 	struct perf_evsel *evsel = zalloc(sizeof(*evsel));
177 
178 	if (evsel != NULL)
179 		perf_evsel__init(evsel, attr, idx);
180 
181 	return evsel;
182 }
183 
184 struct perf_evsel *perf_evsel__newtp_idx(const char *sys, const char *name, int idx)
185 {
186 	struct perf_evsel *evsel = zalloc(sizeof(*evsel));
187 
188 	if (evsel != NULL) {
189 		struct perf_event_attr attr = {
190 			.type	       = PERF_TYPE_TRACEPOINT,
191 			.sample_type   = (PERF_SAMPLE_RAW | PERF_SAMPLE_TIME |
192 					  PERF_SAMPLE_CPU | PERF_SAMPLE_PERIOD),
193 		};
194 
195 		if (asprintf(&evsel->name, "%s:%s", sys, name) < 0)
196 			goto out_free;
197 
198 		evsel->tp_format = trace_event__tp_format(sys, name);
199 		if (evsel->tp_format == NULL)
200 			goto out_free;
201 
202 		event_attr_init(&attr);
203 		attr.config = evsel->tp_format->id;
204 		attr.sample_period = 1;
205 		perf_evsel__init(evsel, &attr, idx);
206 	}
207 
208 	return evsel;
209 
210 out_free:
211 	zfree(&evsel->name);
212 	free(evsel);
213 	return NULL;
214 }
215 
216 const char *perf_evsel__hw_names[PERF_COUNT_HW_MAX] = {
217 	"cycles",
218 	"instructions",
219 	"cache-references",
220 	"cache-misses",
221 	"branches",
222 	"branch-misses",
223 	"bus-cycles",
224 	"stalled-cycles-frontend",
225 	"stalled-cycles-backend",
226 	"ref-cycles",
227 };
228 
229 static const char *__perf_evsel__hw_name(u64 config)
230 {
231 	if (config < PERF_COUNT_HW_MAX && perf_evsel__hw_names[config])
232 		return perf_evsel__hw_names[config];
233 
234 	return "unknown-hardware";
235 }
236 
237 static int perf_evsel__add_modifiers(struct perf_evsel *evsel, char *bf, size_t size)
238 {
239 	int colon = 0, r = 0;
240 	struct perf_event_attr *attr = &evsel->attr;
241 	bool exclude_guest_default = false;
242 
243 #define MOD_PRINT(context, mod)	do {					\
244 		if (!attr->exclude_##context) {				\
245 			if (!colon) colon = ++r;			\
246 			r += scnprintf(bf + r, size - r, "%c", mod);	\
247 		} } while(0)
248 
249 	if (attr->exclude_kernel || attr->exclude_user || attr->exclude_hv) {
250 		MOD_PRINT(kernel, 'k');
251 		MOD_PRINT(user, 'u');
252 		MOD_PRINT(hv, 'h');
253 		exclude_guest_default = true;
254 	}
255 
256 	if (attr->precise_ip) {
257 		if (!colon)
258 			colon = ++r;
259 		r += scnprintf(bf + r, size - r, "%.*s", attr->precise_ip, "ppp");
260 		exclude_guest_default = true;
261 	}
262 
263 	if (attr->exclude_host || attr->exclude_guest == exclude_guest_default) {
264 		MOD_PRINT(host, 'H');
265 		MOD_PRINT(guest, 'G');
266 	}
267 #undef MOD_PRINT
268 	if (colon)
269 		bf[colon - 1] = ':';
270 	return r;
271 }
272 
273 static int perf_evsel__hw_name(struct perf_evsel *evsel, char *bf, size_t size)
274 {
275 	int r = scnprintf(bf, size, "%s", __perf_evsel__hw_name(evsel->attr.config));
276 	return r + perf_evsel__add_modifiers(evsel, bf + r, size - r);
277 }
278 
279 const char *perf_evsel__sw_names[PERF_COUNT_SW_MAX] = {
280 	"cpu-clock",
281 	"task-clock",
282 	"page-faults",
283 	"context-switches",
284 	"cpu-migrations",
285 	"minor-faults",
286 	"major-faults",
287 	"alignment-faults",
288 	"emulation-faults",
289 	"dummy",
290 };
291 
292 static const char *__perf_evsel__sw_name(u64 config)
293 {
294 	if (config < PERF_COUNT_SW_MAX && perf_evsel__sw_names[config])
295 		return perf_evsel__sw_names[config];
296 	return "unknown-software";
297 }
298 
299 static int perf_evsel__sw_name(struct perf_evsel *evsel, char *bf, size_t size)
300 {
301 	int r = scnprintf(bf, size, "%s", __perf_evsel__sw_name(evsel->attr.config));
302 	return r + perf_evsel__add_modifiers(evsel, bf + r, size - r);
303 }
304 
305 static int __perf_evsel__bp_name(char *bf, size_t size, u64 addr, u64 type)
306 {
307 	int r;
308 
309 	r = scnprintf(bf, size, "mem:0x%" PRIx64 ":", addr);
310 
311 	if (type & HW_BREAKPOINT_R)
312 		r += scnprintf(bf + r, size - r, "r");
313 
314 	if (type & HW_BREAKPOINT_W)
315 		r += scnprintf(bf + r, size - r, "w");
316 
317 	if (type & HW_BREAKPOINT_X)
318 		r += scnprintf(bf + r, size - r, "x");
319 
320 	return r;
321 }
322 
323 static int perf_evsel__bp_name(struct perf_evsel *evsel, char *bf, size_t size)
324 {
325 	struct perf_event_attr *attr = &evsel->attr;
326 	int r = __perf_evsel__bp_name(bf, size, attr->bp_addr, attr->bp_type);
327 	return r + perf_evsel__add_modifiers(evsel, bf + r, size - r);
328 }
329 
330 const char *perf_evsel__hw_cache[PERF_COUNT_HW_CACHE_MAX]
331 				[PERF_EVSEL__MAX_ALIASES] = {
332  { "L1-dcache",	"l1-d",		"l1d",		"L1-data",		},
333  { "L1-icache",	"l1-i",		"l1i",		"L1-instruction",	},
334  { "LLC",	"L2",							},
335  { "dTLB",	"d-tlb",	"Data-TLB",				},
336  { "iTLB",	"i-tlb",	"Instruction-TLB",			},
337  { "branch",	"branches",	"bpu",		"btb",		"bpc",	},
338  { "node",								},
339 };
340 
341 const char *perf_evsel__hw_cache_op[PERF_COUNT_HW_CACHE_OP_MAX]
342 				   [PERF_EVSEL__MAX_ALIASES] = {
343  { "load",	"loads",	"read",					},
344  { "store",	"stores",	"write",				},
345  { "prefetch",	"prefetches",	"speculative-read", "speculative-load",	},
346 };
347 
348 const char *perf_evsel__hw_cache_result[PERF_COUNT_HW_CACHE_RESULT_MAX]
349 				       [PERF_EVSEL__MAX_ALIASES] = {
350  { "refs",	"Reference",	"ops",		"access",		},
351  { "misses",	"miss",							},
352 };
353 
354 #define C(x)		PERF_COUNT_HW_CACHE_##x
355 #define CACHE_READ	(1 << C(OP_READ))
356 #define CACHE_WRITE	(1 << C(OP_WRITE))
357 #define CACHE_PREFETCH	(1 << C(OP_PREFETCH))
358 #define COP(x)		(1 << x)
359 
360 /*
361  * cache operartion stat
362  * L1I : Read and prefetch only
363  * ITLB and BPU : Read-only
364  */
365 static unsigned long perf_evsel__hw_cache_stat[C(MAX)] = {
366  [C(L1D)]	= (CACHE_READ | CACHE_WRITE | CACHE_PREFETCH),
367  [C(L1I)]	= (CACHE_READ | CACHE_PREFETCH),
368  [C(LL)]	= (CACHE_READ | CACHE_WRITE | CACHE_PREFETCH),
369  [C(DTLB)]	= (CACHE_READ | CACHE_WRITE | CACHE_PREFETCH),
370  [C(ITLB)]	= (CACHE_READ),
371  [C(BPU)]	= (CACHE_READ),
372  [C(NODE)]	= (CACHE_READ | CACHE_WRITE | CACHE_PREFETCH),
373 };
374 
375 bool perf_evsel__is_cache_op_valid(u8 type, u8 op)
376 {
377 	if (perf_evsel__hw_cache_stat[type] & COP(op))
378 		return true;	/* valid */
379 	else
380 		return false;	/* invalid */
381 }
382 
383 int __perf_evsel__hw_cache_type_op_res_name(u8 type, u8 op, u8 result,
384 					    char *bf, size_t size)
385 {
386 	if (result) {
387 		return scnprintf(bf, size, "%s-%s-%s", perf_evsel__hw_cache[type][0],
388 				 perf_evsel__hw_cache_op[op][0],
389 				 perf_evsel__hw_cache_result[result][0]);
390 	}
391 
392 	return scnprintf(bf, size, "%s-%s", perf_evsel__hw_cache[type][0],
393 			 perf_evsel__hw_cache_op[op][1]);
394 }
395 
396 static int __perf_evsel__hw_cache_name(u64 config, char *bf, size_t size)
397 {
398 	u8 op, result, type = (config >>  0) & 0xff;
399 	const char *err = "unknown-ext-hardware-cache-type";
400 
401 	if (type > PERF_COUNT_HW_CACHE_MAX)
402 		goto out_err;
403 
404 	op = (config >>  8) & 0xff;
405 	err = "unknown-ext-hardware-cache-op";
406 	if (op > PERF_COUNT_HW_CACHE_OP_MAX)
407 		goto out_err;
408 
409 	result = (config >> 16) & 0xff;
410 	err = "unknown-ext-hardware-cache-result";
411 	if (result > PERF_COUNT_HW_CACHE_RESULT_MAX)
412 		goto out_err;
413 
414 	err = "invalid-cache";
415 	if (!perf_evsel__is_cache_op_valid(type, op))
416 		goto out_err;
417 
418 	return __perf_evsel__hw_cache_type_op_res_name(type, op, result, bf, size);
419 out_err:
420 	return scnprintf(bf, size, "%s", err);
421 }
422 
423 static int perf_evsel__hw_cache_name(struct perf_evsel *evsel, char *bf, size_t size)
424 {
425 	int ret = __perf_evsel__hw_cache_name(evsel->attr.config, bf, size);
426 	return ret + perf_evsel__add_modifiers(evsel, bf + ret, size - ret);
427 }
428 
429 static int perf_evsel__raw_name(struct perf_evsel *evsel, char *bf, size_t size)
430 {
431 	int ret = scnprintf(bf, size, "raw 0x%" PRIx64, evsel->attr.config);
432 	return ret + perf_evsel__add_modifiers(evsel, bf + ret, size - ret);
433 }
434 
435 const char *perf_evsel__name(struct perf_evsel *evsel)
436 {
437 	char bf[128];
438 
439 	if (evsel->name)
440 		return evsel->name;
441 
442 	switch (evsel->attr.type) {
443 	case PERF_TYPE_RAW:
444 		perf_evsel__raw_name(evsel, bf, sizeof(bf));
445 		break;
446 
447 	case PERF_TYPE_HARDWARE:
448 		perf_evsel__hw_name(evsel, bf, sizeof(bf));
449 		break;
450 
451 	case PERF_TYPE_HW_CACHE:
452 		perf_evsel__hw_cache_name(evsel, bf, sizeof(bf));
453 		break;
454 
455 	case PERF_TYPE_SOFTWARE:
456 		perf_evsel__sw_name(evsel, bf, sizeof(bf));
457 		break;
458 
459 	case PERF_TYPE_TRACEPOINT:
460 		scnprintf(bf, sizeof(bf), "%s", "unknown tracepoint");
461 		break;
462 
463 	case PERF_TYPE_BREAKPOINT:
464 		perf_evsel__bp_name(evsel, bf, sizeof(bf));
465 		break;
466 
467 	default:
468 		scnprintf(bf, sizeof(bf), "unknown attr type: %d",
469 			  evsel->attr.type);
470 		break;
471 	}
472 
473 	evsel->name = strdup(bf);
474 
475 	return evsel->name ?: "unknown";
476 }
477 
478 const char *perf_evsel__group_name(struct perf_evsel *evsel)
479 {
480 	return evsel->group_name ?: "anon group";
481 }
482 
483 int perf_evsel__group_desc(struct perf_evsel *evsel, char *buf, size_t size)
484 {
485 	int ret;
486 	struct perf_evsel *pos;
487 	const char *group_name = perf_evsel__group_name(evsel);
488 
489 	ret = scnprintf(buf, size, "%s", group_name);
490 
491 	ret += scnprintf(buf + ret, size - ret, " { %s",
492 			 perf_evsel__name(evsel));
493 
494 	for_each_group_member(pos, evsel)
495 		ret += scnprintf(buf + ret, size - ret, ", %s",
496 				 perf_evsel__name(pos));
497 
498 	ret += scnprintf(buf + ret, size - ret, " }");
499 
500 	return ret;
501 }
502 
503 /*
504  * The enable_on_exec/disabled value strategy:
505  *
506  *  1) For any type of traced program:
507  *    - all independent events and group leaders are disabled
508  *    - all group members are enabled
509  *
510  *     Group members are ruled by group leaders. They need to
511  *     be enabled, because the group scheduling relies on that.
512  *
513  *  2) For traced programs executed by perf:
514  *     - all independent events and group leaders have
515  *       enable_on_exec set
516  *     - we don't specifically enable or disable any event during
517  *       the record command
518  *
519  *     Independent events and group leaders are initially disabled
520  *     and get enabled by exec. Group members are ruled by group
521  *     leaders as stated in 1).
522  *
523  *  3) For traced programs attached by perf (pid/tid):
524  *     - we specifically enable or disable all events during
525  *       the record command
526  *
527  *     When attaching events to already running traced we
528  *     enable/disable events specifically, as there's no
529  *     initial traced exec call.
530  */
531 void perf_evsel__config(struct perf_evsel *evsel, struct record_opts *opts)
532 {
533 	struct perf_evsel *leader = evsel->leader;
534 	struct perf_event_attr *attr = &evsel->attr;
535 	int track = !evsel->idx; /* only the first counter needs these */
536 	bool per_cpu = opts->target.default_per_cpu && !opts->target.per_thread;
537 
538 	attr->sample_id_all = perf_missing_features.sample_id_all ? 0 : 1;
539 	attr->inherit	    = !opts->no_inherit;
540 
541 	perf_evsel__set_sample_bit(evsel, IP);
542 	perf_evsel__set_sample_bit(evsel, TID);
543 
544 	if (evsel->sample_read) {
545 		perf_evsel__set_sample_bit(evsel, READ);
546 
547 		/*
548 		 * We need ID even in case of single event, because
549 		 * PERF_SAMPLE_READ process ID specific data.
550 		 */
551 		perf_evsel__set_sample_id(evsel, false);
552 
553 		/*
554 		 * Apply group format only if we belong to group
555 		 * with more than one members.
556 		 */
557 		if (leader->nr_members > 1) {
558 			attr->read_format |= PERF_FORMAT_GROUP;
559 			attr->inherit = 0;
560 		}
561 	}
562 
563 	/*
564 	 * We default some events to a 1 default interval. But keep
565 	 * it a weak assumption overridable by the user.
566 	 */
567 	if (!attr->sample_period || (opts->user_freq != UINT_MAX &&
568 				     opts->user_interval != ULLONG_MAX)) {
569 		if (opts->freq) {
570 			perf_evsel__set_sample_bit(evsel, PERIOD);
571 			attr->freq		= 1;
572 			attr->sample_freq	= opts->freq;
573 		} else {
574 			attr->sample_period = opts->default_interval;
575 		}
576 	}
577 
578 	/*
579 	 * Disable sampling for all group members other
580 	 * than leader in case leader 'leads' the sampling.
581 	 */
582 	if ((leader != evsel) && leader->sample_read) {
583 		attr->sample_freq   = 0;
584 		attr->sample_period = 0;
585 	}
586 
587 	if (opts->no_samples)
588 		attr->sample_freq = 0;
589 
590 	if (opts->inherit_stat)
591 		attr->inherit_stat = 1;
592 
593 	if (opts->sample_address) {
594 		perf_evsel__set_sample_bit(evsel, ADDR);
595 		attr->mmap_data = track;
596 	}
597 
598 	if (opts->call_graph) {
599 		perf_evsel__set_sample_bit(evsel, CALLCHAIN);
600 
601 		if (opts->call_graph == CALLCHAIN_DWARF) {
602 			perf_evsel__set_sample_bit(evsel, REGS_USER);
603 			perf_evsel__set_sample_bit(evsel, STACK_USER);
604 			attr->sample_regs_user = PERF_REGS_MASK;
605 			attr->sample_stack_user = opts->stack_dump_size;
606 			attr->exclude_callchain_user = 1;
607 		}
608 	}
609 
610 	if (target__has_cpu(&opts->target))
611 		perf_evsel__set_sample_bit(evsel, CPU);
612 
613 	if (opts->period)
614 		perf_evsel__set_sample_bit(evsel, PERIOD);
615 
616 	if (!perf_missing_features.sample_id_all &&
617 	    (opts->sample_time || !opts->no_inherit ||
618 	     target__has_cpu(&opts->target) || per_cpu))
619 		perf_evsel__set_sample_bit(evsel, TIME);
620 
621 	if (opts->raw_samples) {
622 		perf_evsel__set_sample_bit(evsel, TIME);
623 		perf_evsel__set_sample_bit(evsel, RAW);
624 		perf_evsel__set_sample_bit(evsel, CPU);
625 	}
626 
627 	if (opts->sample_address)
628 		perf_evsel__set_sample_bit(evsel, DATA_SRC);
629 
630 	if (opts->no_buffering) {
631 		attr->watermark = 0;
632 		attr->wakeup_events = 1;
633 	}
634 	if (opts->branch_stack) {
635 		perf_evsel__set_sample_bit(evsel, BRANCH_STACK);
636 		attr->branch_sample_type = opts->branch_stack;
637 	}
638 
639 	if (opts->sample_weight)
640 		perf_evsel__set_sample_bit(evsel, WEIGHT);
641 
642 	attr->mmap  = track;
643 	attr->comm  = track;
644 
645 	if (opts->sample_transaction)
646 		perf_evsel__set_sample_bit(evsel, TRANSACTION);
647 
648 	/*
649 	 * XXX see the function comment above
650 	 *
651 	 * Disabling only independent events or group leaders,
652 	 * keeping group members enabled.
653 	 */
654 	if (perf_evsel__is_group_leader(evsel))
655 		attr->disabled = 1;
656 
657 	/*
658 	 * Setting enable_on_exec for independent events and
659 	 * group leaders for traced executed by perf.
660 	 */
661 	if (target__none(&opts->target) && perf_evsel__is_group_leader(evsel) &&
662 		!opts->initial_delay)
663 		attr->enable_on_exec = 1;
664 }
665 
666 int perf_evsel__alloc_fd(struct perf_evsel *evsel, int ncpus, int nthreads)
667 {
668 	int cpu, thread;
669 	evsel->fd = xyarray__new(ncpus, nthreads, sizeof(int));
670 
671 	if (evsel->fd) {
672 		for (cpu = 0; cpu < ncpus; cpu++) {
673 			for (thread = 0; thread < nthreads; thread++) {
674 				FD(evsel, cpu, thread) = -1;
675 			}
676 		}
677 	}
678 
679 	return evsel->fd != NULL ? 0 : -ENOMEM;
680 }
681 
682 static int perf_evsel__run_ioctl(struct perf_evsel *evsel, int ncpus, int nthreads,
683 			  int ioc,  void *arg)
684 {
685 	int cpu, thread;
686 
687 	for (cpu = 0; cpu < ncpus; cpu++) {
688 		for (thread = 0; thread < nthreads; thread++) {
689 			int fd = FD(evsel, cpu, thread),
690 			    err = ioctl(fd, ioc, arg);
691 
692 			if (err)
693 				return err;
694 		}
695 	}
696 
697 	return 0;
698 }
699 
700 int perf_evsel__set_filter(struct perf_evsel *evsel, int ncpus, int nthreads,
701 			   const char *filter)
702 {
703 	return perf_evsel__run_ioctl(evsel, ncpus, nthreads,
704 				     PERF_EVENT_IOC_SET_FILTER,
705 				     (void *)filter);
706 }
707 
708 int perf_evsel__enable(struct perf_evsel *evsel, int ncpus, int nthreads)
709 {
710 	return perf_evsel__run_ioctl(evsel, ncpus, nthreads,
711 				     PERF_EVENT_IOC_ENABLE,
712 				     0);
713 }
714 
715 int perf_evsel__alloc_id(struct perf_evsel *evsel, int ncpus, int nthreads)
716 {
717 	evsel->sample_id = xyarray__new(ncpus, nthreads, sizeof(struct perf_sample_id));
718 	if (evsel->sample_id == NULL)
719 		return -ENOMEM;
720 
721 	evsel->id = zalloc(ncpus * nthreads * sizeof(u64));
722 	if (evsel->id == NULL) {
723 		xyarray__delete(evsel->sample_id);
724 		evsel->sample_id = NULL;
725 		return -ENOMEM;
726 	}
727 
728 	return 0;
729 }
730 
731 void perf_evsel__reset_counts(struct perf_evsel *evsel, int ncpus)
732 {
733 	memset(evsel->counts, 0, (sizeof(*evsel->counts) +
734 				 (ncpus * sizeof(struct perf_counts_values))));
735 }
736 
737 int perf_evsel__alloc_counts(struct perf_evsel *evsel, int ncpus)
738 {
739 	evsel->counts = zalloc((sizeof(*evsel->counts) +
740 				(ncpus * sizeof(struct perf_counts_values))));
741 	return evsel->counts != NULL ? 0 : -ENOMEM;
742 }
743 
744 void perf_evsel__free_fd(struct perf_evsel *evsel)
745 {
746 	xyarray__delete(evsel->fd);
747 	evsel->fd = NULL;
748 }
749 
750 void perf_evsel__free_id(struct perf_evsel *evsel)
751 {
752 	xyarray__delete(evsel->sample_id);
753 	evsel->sample_id = NULL;
754 	zfree(&evsel->id);
755 }
756 
757 void perf_evsel__close_fd(struct perf_evsel *evsel, int ncpus, int nthreads)
758 {
759 	int cpu, thread;
760 
761 	for (cpu = 0; cpu < ncpus; cpu++)
762 		for (thread = 0; thread < nthreads; ++thread) {
763 			close(FD(evsel, cpu, thread));
764 			FD(evsel, cpu, thread) = -1;
765 		}
766 }
767 
768 void perf_evsel__free_counts(struct perf_evsel *evsel)
769 {
770 	zfree(&evsel->counts);
771 }
772 
773 void perf_evsel__exit(struct perf_evsel *evsel)
774 {
775 	assert(list_empty(&evsel->node));
776 	perf_evsel__free_fd(evsel);
777 	perf_evsel__free_id(evsel);
778 }
779 
780 void perf_evsel__delete(struct perf_evsel *evsel)
781 {
782 	perf_evsel__exit(evsel);
783 	close_cgroup(evsel->cgrp);
784 	zfree(&evsel->group_name);
785 	if (evsel->tp_format)
786 		pevent_free_format(evsel->tp_format);
787 	zfree(&evsel->name);
788 	free(evsel);
789 }
790 
791 static inline void compute_deltas(struct perf_evsel *evsel,
792 				  int cpu,
793 				  struct perf_counts_values *count)
794 {
795 	struct perf_counts_values tmp;
796 
797 	if (!evsel->prev_raw_counts)
798 		return;
799 
800 	if (cpu == -1) {
801 		tmp = evsel->prev_raw_counts->aggr;
802 		evsel->prev_raw_counts->aggr = *count;
803 	} else {
804 		tmp = evsel->prev_raw_counts->cpu[cpu];
805 		evsel->prev_raw_counts->cpu[cpu] = *count;
806 	}
807 
808 	count->val = count->val - tmp.val;
809 	count->ena = count->ena - tmp.ena;
810 	count->run = count->run - tmp.run;
811 }
812 
813 int __perf_evsel__read_on_cpu(struct perf_evsel *evsel,
814 			      int cpu, int thread, bool scale)
815 {
816 	struct perf_counts_values count;
817 	size_t nv = scale ? 3 : 1;
818 
819 	if (FD(evsel, cpu, thread) < 0)
820 		return -EINVAL;
821 
822 	if (evsel->counts == NULL && perf_evsel__alloc_counts(evsel, cpu + 1) < 0)
823 		return -ENOMEM;
824 
825 	if (readn(FD(evsel, cpu, thread), &count, nv * sizeof(u64)) < 0)
826 		return -errno;
827 
828 	compute_deltas(evsel, cpu, &count);
829 
830 	if (scale) {
831 		if (count.run == 0)
832 			count.val = 0;
833 		else if (count.run < count.ena)
834 			count.val = (u64)((double)count.val * count.ena / count.run + 0.5);
835 	} else
836 		count.ena = count.run = 0;
837 
838 	evsel->counts->cpu[cpu] = count;
839 	return 0;
840 }
841 
842 int __perf_evsel__read(struct perf_evsel *evsel,
843 		       int ncpus, int nthreads, bool scale)
844 {
845 	size_t nv = scale ? 3 : 1;
846 	int cpu, thread;
847 	struct perf_counts_values *aggr = &evsel->counts->aggr, count;
848 
849 	aggr->val = aggr->ena = aggr->run = 0;
850 
851 	for (cpu = 0; cpu < ncpus; cpu++) {
852 		for (thread = 0; thread < nthreads; thread++) {
853 			if (FD(evsel, cpu, thread) < 0)
854 				continue;
855 
856 			if (readn(FD(evsel, cpu, thread),
857 				  &count, nv * sizeof(u64)) < 0)
858 				return -errno;
859 
860 			aggr->val += count.val;
861 			if (scale) {
862 				aggr->ena += count.ena;
863 				aggr->run += count.run;
864 			}
865 		}
866 	}
867 
868 	compute_deltas(evsel, -1, aggr);
869 
870 	evsel->counts->scaled = 0;
871 	if (scale) {
872 		if (aggr->run == 0) {
873 			evsel->counts->scaled = -1;
874 			aggr->val = 0;
875 			return 0;
876 		}
877 
878 		if (aggr->run < aggr->ena) {
879 			evsel->counts->scaled = 1;
880 			aggr->val = (u64)((double)aggr->val * aggr->ena / aggr->run + 0.5);
881 		}
882 	} else
883 		aggr->ena = aggr->run = 0;
884 
885 	return 0;
886 }
887 
888 static int get_group_fd(struct perf_evsel *evsel, int cpu, int thread)
889 {
890 	struct perf_evsel *leader = evsel->leader;
891 	int fd;
892 
893 	if (perf_evsel__is_group_leader(evsel))
894 		return -1;
895 
896 	/*
897 	 * Leader must be already processed/open,
898 	 * if not it's a bug.
899 	 */
900 	BUG_ON(!leader->fd);
901 
902 	fd = FD(leader, cpu, thread);
903 	BUG_ON(fd == -1);
904 
905 	return fd;
906 }
907 
908 #define __PRINT_ATTR(fmt, cast, field)  \
909 	fprintf(fp, "  %-19s "fmt"\n", #field, cast attr->field)
910 
911 #define PRINT_ATTR_U32(field)  __PRINT_ATTR("%u" , , field)
912 #define PRINT_ATTR_X32(field)  __PRINT_ATTR("%#x", , field)
913 #define PRINT_ATTR_U64(field)  __PRINT_ATTR("%" PRIu64, (uint64_t), field)
914 #define PRINT_ATTR_X64(field)  __PRINT_ATTR("%#"PRIx64, (uint64_t), field)
915 
916 #define PRINT_ATTR2N(name1, field1, name2, field2)	\
917 	fprintf(fp, "  %-19s %u    %-19s %u\n",		\
918 	name1, attr->field1, name2, attr->field2)
919 
920 #define PRINT_ATTR2(field1, field2) \
921 	PRINT_ATTR2N(#field1, field1, #field2, field2)
922 
923 static size_t perf_event_attr__fprintf(struct perf_event_attr *attr, FILE *fp)
924 {
925 	size_t ret = 0;
926 
927 	ret += fprintf(fp, "%.60s\n", graph_dotted_line);
928 	ret += fprintf(fp, "perf_event_attr:\n");
929 
930 	ret += PRINT_ATTR_U32(type);
931 	ret += PRINT_ATTR_U32(size);
932 	ret += PRINT_ATTR_X64(config);
933 	ret += PRINT_ATTR_U64(sample_period);
934 	ret += PRINT_ATTR_U64(sample_freq);
935 	ret += PRINT_ATTR_X64(sample_type);
936 	ret += PRINT_ATTR_X64(read_format);
937 
938 	ret += PRINT_ATTR2(disabled, inherit);
939 	ret += PRINT_ATTR2(pinned, exclusive);
940 	ret += PRINT_ATTR2(exclude_user, exclude_kernel);
941 	ret += PRINT_ATTR2(exclude_hv, exclude_idle);
942 	ret += PRINT_ATTR2(mmap, comm);
943 	ret += PRINT_ATTR2(freq, inherit_stat);
944 	ret += PRINT_ATTR2(enable_on_exec, task);
945 	ret += PRINT_ATTR2(watermark, precise_ip);
946 	ret += PRINT_ATTR2(mmap_data, sample_id_all);
947 	ret += PRINT_ATTR2(exclude_host, exclude_guest);
948 	ret += PRINT_ATTR2N("excl.callchain_kern", exclude_callchain_kernel,
949 			    "excl.callchain_user", exclude_callchain_user);
950 	ret += PRINT_ATTR_U32(mmap2);
951 
952 	ret += PRINT_ATTR_U32(wakeup_events);
953 	ret += PRINT_ATTR_U32(wakeup_watermark);
954 	ret += PRINT_ATTR_X32(bp_type);
955 	ret += PRINT_ATTR_X64(bp_addr);
956 	ret += PRINT_ATTR_X64(config1);
957 	ret += PRINT_ATTR_U64(bp_len);
958 	ret += PRINT_ATTR_X64(config2);
959 	ret += PRINT_ATTR_X64(branch_sample_type);
960 	ret += PRINT_ATTR_X64(sample_regs_user);
961 	ret += PRINT_ATTR_U32(sample_stack_user);
962 
963 	ret += fprintf(fp, "%.60s\n", graph_dotted_line);
964 
965 	return ret;
966 }
967 
968 static int __perf_evsel__open(struct perf_evsel *evsel, struct cpu_map *cpus,
969 			      struct thread_map *threads)
970 {
971 	int cpu, thread;
972 	unsigned long flags = 0;
973 	int pid = -1, err;
974 	enum { NO_CHANGE, SET_TO_MAX, INCREASED_MAX } set_rlimit = NO_CHANGE;
975 
976 	if (evsel->fd == NULL &&
977 	    perf_evsel__alloc_fd(evsel, cpus->nr, threads->nr) < 0)
978 		return -ENOMEM;
979 
980 	if (evsel->cgrp) {
981 		flags = PERF_FLAG_PID_CGROUP;
982 		pid = evsel->cgrp->fd;
983 	}
984 
985 fallback_missing_features:
986 	if (perf_missing_features.mmap2)
987 		evsel->attr.mmap2 = 0;
988 	if (perf_missing_features.exclude_guest)
989 		evsel->attr.exclude_guest = evsel->attr.exclude_host = 0;
990 retry_sample_id:
991 	if (perf_missing_features.sample_id_all)
992 		evsel->attr.sample_id_all = 0;
993 
994 	if (verbose >= 2)
995 		perf_event_attr__fprintf(&evsel->attr, stderr);
996 
997 	for (cpu = 0; cpu < cpus->nr; cpu++) {
998 
999 		for (thread = 0; thread < threads->nr; thread++) {
1000 			int group_fd;
1001 
1002 			if (!evsel->cgrp)
1003 				pid = threads->map[thread];
1004 
1005 			group_fd = get_group_fd(evsel, cpu, thread);
1006 retry_open:
1007 			pr_debug2("perf_event_open: pid %d  cpu %d  group_fd %d  flags %#lx\n",
1008 				  pid, cpus->map[cpu], group_fd, flags);
1009 
1010 			FD(evsel, cpu, thread) = sys_perf_event_open(&evsel->attr,
1011 								     pid,
1012 								     cpus->map[cpu],
1013 								     group_fd, flags);
1014 			if (FD(evsel, cpu, thread) < 0) {
1015 				err = -errno;
1016 				pr_debug2("perf_event_open failed, error %d\n",
1017 					  err);
1018 				goto try_fallback;
1019 			}
1020 			set_rlimit = NO_CHANGE;
1021 		}
1022 	}
1023 
1024 	return 0;
1025 
1026 try_fallback:
1027 	/*
1028 	 * perf stat needs between 5 and 22 fds per CPU. When we run out
1029 	 * of them try to increase the limits.
1030 	 */
1031 	if (err == -EMFILE && set_rlimit < INCREASED_MAX) {
1032 		struct rlimit l;
1033 		int old_errno = errno;
1034 
1035 		if (getrlimit(RLIMIT_NOFILE, &l) == 0) {
1036 			if (set_rlimit == NO_CHANGE)
1037 				l.rlim_cur = l.rlim_max;
1038 			else {
1039 				l.rlim_cur = l.rlim_max + 1000;
1040 				l.rlim_max = l.rlim_cur;
1041 			}
1042 			if (setrlimit(RLIMIT_NOFILE, &l) == 0) {
1043 				set_rlimit++;
1044 				errno = old_errno;
1045 				goto retry_open;
1046 			}
1047 		}
1048 		errno = old_errno;
1049 	}
1050 
1051 	if (err != -EINVAL || cpu > 0 || thread > 0)
1052 		goto out_close;
1053 
1054 	if (!perf_missing_features.mmap2 && evsel->attr.mmap2) {
1055 		perf_missing_features.mmap2 = true;
1056 		goto fallback_missing_features;
1057 	} else if (!perf_missing_features.exclude_guest &&
1058 		   (evsel->attr.exclude_guest || evsel->attr.exclude_host)) {
1059 		perf_missing_features.exclude_guest = true;
1060 		goto fallback_missing_features;
1061 	} else if (!perf_missing_features.sample_id_all) {
1062 		perf_missing_features.sample_id_all = true;
1063 		goto retry_sample_id;
1064 	}
1065 
1066 out_close:
1067 	do {
1068 		while (--thread >= 0) {
1069 			close(FD(evsel, cpu, thread));
1070 			FD(evsel, cpu, thread) = -1;
1071 		}
1072 		thread = threads->nr;
1073 	} while (--cpu >= 0);
1074 	return err;
1075 }
1076 
1077 void perf_evsel__close(struct perf_evsel *evsel, int ncpus, int nthreads)
1078 {
1079 	if (evsel->fd == NULL)
1080 		return;
1081 
1082 	perf_evsel__close_fd(evsel, ncpus, nthreads);
1083 	perf_evsel__free_fd(evsel);
1084 }
1085 
1086 static struct {
1087 	struct cpu_map map;
1088 	int cpus[1];
1089 } empty_cpu_map = {
1090 	.map.nr	= 1,
1091 	.cpus	= { -1, },
1092 };
1093 
1094 static struct {
1095 	struct thread_map map;
1096 	int threads[1];
1097 } empty_thread_map = {
1098 	.map.nr	 = 1,
1099 	.threads = { -1, },
1100 };
1101 
1102 int perf_evsel__open(struct perf_evsel *evsel, struct cpu_map *cpus,
1103 		     struct thread_map *threads)
1104 {
1105 	if (cpus == NULL) {
1106 		/* Work around old compiler warnings about strict aliasing */
1107 		cpus = &empty_cpu_map.map;
1108 	}
1109 
1110 	if (threads == NULL)
1111 		threads = &empty_thread_map.map;
1112 
1113 	return __perf_evsel__open(evsel, cpus, threads);
1114 }
1115 
1116 int perf_evsel__open_per_cpu(struct perf_evsel *evsel,
1117 			     struct cpu_map *cpus)
1118 {
1119 	return __perf_evsel__open(evsel, cpus, &empty_thread_map.map);
1120 }
1121 
1122 int perf_evsel__open_per_thread(struct perf_evsel *evsel,
1123 				struct thread_map *threads)
1124 {
1125 	return __perf_evsel__open(evsel, &empty_cpu_map.map, threads);
1126 }
1127 
1128 static int perf_evsel__parse_id_sample(const struct perf_evsel *evsel,
1129 				       const union perf_event *event,
1130 				       struct perf_sample *sample)
1131 {
1132 	u64 type = evsel->attr.sample_type;
1133 	const u64 *array = event->sample.array;
1134 	bool swapped = evsel->needs_swap;
1135 	union u64_swap u;
1136 
1137 	array += ((event->header.size -
1138 		   sizeof(event->header)) / sizeof(u64)) - 1;
1139 
1140 	if (type & PERF_SAMPLE_IDENTIFIER) {
1141 		sample->id = *array;
1142 		array--;
1143 	}
1144 
1145 	if (type & PERF_SAMPLE_CPU) {
1146 		u.val64 = *array;
1147 		if (swapped) {
1148 			/* undo swap of u64, then swap on individual u32s */
1149 			u.val64 = bswap_64(u.val64);
1150 			u.val32[0] = bswap_32(u.val32[0]);
1151 		}
1152 
1153 		sample->cpu = u.val32[0];
1154 		array--;
1155 	}
1156 
1157 	if (type & PERF_SAMPLE_STREAM_ID) {
1158 		sample->stream_id = *array;
1159 		array--;
1160 	}
1161 
1162 	if (type & PERF_SAMPLE_ID) {
1163 		sample->id = *array;
1164 		array--;
1165 	}
1166 
1167 	if (type & PERF_SAMPLE_TIME) {
1168 		sample->time = *array;
1169 		array--;
1170 	}
1171 
1172 	if (type & PERF_SAMPLE_TID) {
1173 		u.val64 = *array;
1174 		if (swapped) {
1175 			/* undo swap of u64, then swap on individual u32s */
1176 			u.val64 = bswap_64(u.val64);
1177 			u.val32[0] = bswap_32(u.val32[0]);
1178 			u.val32[1] = bswap_32(u.val32[1]);
1179 		}
1180 
1181 		sample->pid = u.val32[0];
1182 		sample->tid = u.val32[1];
1183 		array--;
1184 	}
1185 
1186 	return 0;
1187 }
1188 
1189 static inline bool overflow(const void *endp, u16 max_size, const void *offset,
1190 			    u64 size)
1191 {
1192 	return size > max_size || offset + size > endp;
1193 }
1194 
1195 #define OVERFLOW_CHECK(offset, size, max_size)				\
1196 	do {								\
1197 		if (overflow(endp, (max_size), (offset), (size)))	\
1198 			return -EFAULT;					\
1199 	} while (0)
1200 
1201 #define OVERFLOW_CHECK_u64(offset) \
1202 	OVERFLOW_CHECK(offset, sizeof(u64), sizeof(u64))
1203 
1204 int perf_evsel__parse_sample(struct perf_evsel *evsel, union perf_event *event,
1205 			     struct perf_sample *data)
1206 {
1207 	u64 type = evsel->attr.sample_type;
1208 	bool swapped = evsel->needs_swap;
1209 	const u64 *array;
1210 	u16 max_size = event->header.size;
1211 	const void *endp = (void *)event + max_size;
1212 	u64 sz;
1213 
1214 	/*
1215 	 * used for cross-endian analysis. See git commit 65014ab3
1216 	 * for why this goofiness is needed.
1217 	 */
1218 	union u64_swap u;
1219 
1220 	memset(data, 0, sizeof(*data));
1221 	data->cpu = data->pid = data->tid = -1;
1222 	data->stream_id = data->id = data->time = -1ULL;
1223 	data->period = 1;
1224 	data->weight = 0;
1225 
1226 	if (event->header.type != PERF_RECORD_SAMPLE) {
1227 		if (!evsel->attr.sample_id_all)
1228 			return 0;
1229 		return perf_evsel__parse_id_sample(evsel, event, data);
1230 	}
1231 
1232 	array = event->sample.array;
1233 
1234 	/*
1235 	 * The evsel's sample_size is based on PERF_SAMPLE_MASK which includes
1236 	 * up to PERF_SAMPLE_PERIOD.  After that overflow() must be used to
1237 	 * check the format does not go past the end of the event.
1238 	 */
1239 	if (evsel->sample_size + sizeof(event->header) > event->header.size)
1240 		return -EFAULT;
1241 
1242 	data->id = -1ULL;
1243 	if (type & PERF_SAMPLE_IDENTIFIER) {
1244 		data->id = *array;
1245 		array++;
1246 	}
1247 
1248 	if (type & PERF_SAMPLE_IP) {
1249 		data->ip = *array;
1250 		array++;
1251 	}
1252 
1253 	if (type & PERF_SAMPLE_TID) {
1254 		u.val64 = *array;
1255 		if (swapped) {
1256 			/* undo swap of u64, then swap on individual u32s */
1257 			u.val64 = bswap_64(u.val64);
1258 			u.val32[0] = bswap_32(u.val32[0]);
1259 			u.val32[1] = bswap_32(u.val32[1]);
1260 		}
1261 
1262 		data->pid = u.val32[0];
1263 		data->tid = u.val32[1];
1264 		array++;
1265 	}
1266 
1267 	if (type & PERF_SAMPLE_TIME) {
1268 		data->time = *array;
1269 		array++;
1270 	}
1271 
1272 	data->addr = 0;
1273 	if (type & PERF_SAMPLE_ADDR) {
1274 		data->addr = *array;
1275 		array++;
1276 	}
1277 
1278 	if (type & PERF_SAMPLE_ID) {
1279 		data->id = *array;
1280 		array++;
1281 	}
1282 
1283 	if (type & PERF_SAMPLE_STREAM_ID) {
1284 		data->stream_id = *array;
1285 		array++;
1286 	}
1287 
1288 	if (type & PERF_SAMPLE_CPU) {
1289 
1290 		u.val64 = *array;
1291 		if (swapped) {
1292 			/* undo swap of u64, then swap on individual u32s */
1293 			u.val64 = bswap_64(u.val64);
1294 			u.val32[0] = bswap_32(u.val32[0]);
1295 		}
1296 
1297 		data->cpu = u.val32[0];
1298 		array++;
1299 	}
1300 
1301 	if (type & PERF_SAMPLE_PERIOD) {
1302 		data->period = *array;
1303 		array++;
1304 	}
1305 
1306 	if (type & PERF_SAMPLE_READ) {
1307 		u64 read_format = evsel->attr.read_format;
1308 
1309 		OVERFLOW_CHECK_u64(array);
1310 		if (read_format & PERF_FORMAT_GROUP)
1311 			data->read.group.nr = *array;
1312 		else
1313 			data->read.one.value = *array;
1314 
1315 		array++;
1316 
1317 		if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) {
1318 			OVERFLOW_CHECK_u64(array);
1319 			data->read.time_enabled = *array;
1320 			array++;
1321 		}
1322 
1323 		if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) {
1324 			OVERFLOW_CHECK_u64(array);
1325 			data->read.time_running = *array;
1326 			array++;
1327 		}
1328 
1329 		/* PERF_FORMAT_ID is forced for PERF_SAMPLE_READ */
1330 		if (read_format & PERF_FORMAT_GROUP) {
1331 			const u64 max_group_nr = UINT64_MAX /
1332 					sizeof(struct sample_read_value);
1333 
1334 			if (data->read.group.nr > max_group_nr)
1335 				return -EFAULT;
1336 			sz = data->read.group.nr *
1337 			     sizeof(struct sample_read_value);
1338 			OVERFLOW_CHECK(array, sz, max_size);
1339 			data->read.group.values =
1340 					(struct sample_read_value *)array;
1341 			array = (void *)array + sz;
1342 		} else {
1343 			OVERFLOW_CHECK_u64(array);
1344 			data->read.one.id = *array;
1345 			array++;
1346 		}
1347 	}
1348 
1349 	if (type & PERF_SAMPLE_CALLCHAIN) {
1350 		const u64 max_callchain_nr = UINT64_MAX / sizeof(u64);
1351 
1352 		OVERFLOW_CHECK_u64(array);
1353 		data->callchain = (struct ip_callchain *)array++;
1354 		if (data->callchain->nr > max_callchain_nr)
1355 			return -EFAULT;
1356 		sz = data->callchain->nr * sizeof(u64);
1357 		OVERFLOW_CHECK(array, sz, max_size);
1358 		array = (void *)array + sz;
1359 	}
1360 
1361 	if (type & PERF_SAMPLE_RAW) {
1362 		OVERFLOW_CHECK_u64(array);
1363 		u.val64 = *array;
1364 		if (WARN_ONCE(swapped,
1365 			      "Endianness of raw data not corrected!\n")) {
1366 			/* undo swap of u64, then swap on individual u32s */
1367 			u.val64 = bswap_64(u.val64);
1368 			u.val32[0] = bswap_32(u.val32[0]);
1369 			u.val32[1] = bswap_32(u.val32[1]);
1370 		}
1371 		data->raw_size = u.val32[0];
1372 		array = (void *)array + sizeof(u32);
1373 
1374 		OVERFLOW_CHECK(array, data->raw_size, max_size);
1375 		data->raw_data = (void *)array;
1376 		array = (void *)array + data->raw_size;
1377 	}
1378 
1379 	if (type & PERF_SAMPLE_BRANCH_STACK) {
1380 		const u64 max_branch_nr = UINT64_MAX /
1381 					  sizeof(struct branch_entry);
1382 
1383 		OVERFLOW_CHECK_u64(array);
1384 		data->branch_stack = (struct branch_stack *)array++;
1385 
1386 		if (data->branch_stack->nr > max_branch_nr)
1387 			return -EFAULT;
1388 		sz = data->branch_stack->nr * sizeof(struct branch_entry);
1389 		OVERFLOW_CHECK(array, sz, max_size);
1390 		array = (void *)array + sz;
1391 	}
1392 
1393 	if (type & PERF_SAMPLE_REGS_USER) {
1394 		OVERFLOW_CHECK_u64(array);
1395 		data->user_regs.abi = *array;
1396 		array++;
1397 
1398 		if (data->user_regs.abi) {
1399 			u64 regs_user = evsel->attr.sample_regs_user;
1400 
1401 			sz = hweight_long(regs_user) * sizeof(u64);
1402 			OVERFLOW_CHECK(array, sz, max_size);
1403 			data->user_regs.regs = (u64 *)array;
1404 			array = (void *)array + sz;
1405 		}
1406 	}
1407 
1408 	if (type & PERF_SAMPLE_STACK_USER) {
1409 		OVERFLOW_CHECK_u64(array);
1410 		sz = *array++;
1411 
1412 		data->user_stack.offset = ((char *)(array - 1)
1413 					  - (char *) event);
1414 
1415 		if (!sz) {
1416 			data->user_stack.size = 0;
1417 		} else {
1418 			OVERFLOW_CHECK(array, sz, max_size);
1419 			data->user_stack.data = (char *)array;
1420 			array = (void *)array + sz;
1421 			OVERFLOW_CHECK_u64(array);
1422 			data->user_stack.size = *array++;
1423 			if (WARN_ONCE(data->user_stack.size > sz,
1424 				      "user stack dump failure\n"))
1425 				return -EFAULT;
1426 		}
1427 	}
1428 
1429 	data->weight = 0;
1430 	if (type & PERF_SAMPLE_WEIGHT) {
1431 		OVERFLOW_CHECK_u64(array);
1432 		data->weight = *array;
1433 		array++;
1434 	}
1435 
1436 	data->data_src = PERF_MEM_DATA_SRC_NONE;
1437 	if (type & PERF_SAMPLE_DATA_SRC) {
1438 		OVERFLOW_CHECK_u64(array);
1439 		data->data_src = *array;
1440 		array++;
1441 	}
1442 
1443 	data->transaction = 0;
1444 	if (type & PERF_SAMPLE_TRANSACTION) {
1445 		OVERFLOW_CHECK_u64(array);
1446 		data->transaction = *array;
1447 		array++;
1448 	}
1449 
1450 	return 0;
1451 }
1452 
1453 size_t perf_event__sample_event_size(const struct perf_sample *sample, u64 type,
1454 				     u64 sample_regs_user, u64 read_format)
1455 {
1456 	size_t sz, result = sizeof(struct sample_event);
1457 
1458 	if (type & PERF_SAMPLE_IDENTIFIER)
1459 		result += sizeof(u64);
1460 
1461 	if (type & PERF_SAMPLE_IP)
1462 		result += sizeof(u64);
1463 
1464 	if (type & PERF_SAMPLE_TID)
1465 		result += sizeof(u64);
1466 
1467 	if (type & PERF_SAMPLE_TIME)
1468 		result += sizeof(u64);
1469 
1470 	if (type & PERF_SAMPLE_ADDR)
1471 		result += sizeof(u64);
1472 
1473 	if (type & PERF_SAMPLE_ID)
1474 		result += sizeof(u64);
1475 
1476 	if (type & PERF_SAMPLE_STREAM_ID)
1477 		result += sizeof(u64);
1478 
1479 	if (type & PERF_SAMPLE_CPU)
1480 		result += sizeof(u64);
1481 
1482 	if (type & PERF_SAMPLE_PERIOD)
1483 		result += sizeof(u64);
1484 
1485 	if (type & PERF_SAMPLE_READ) {
1486 		result += sizeof(u64);
1487 		if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED)
1488 			result += sizeof(u64);
1489 		if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING)
1490 			result += sizeof(u64);
1491 		/* PERF_FORMAT_ID is forced for PERF_SAMPLE_READ */
1492 		if (read_format & PERF_FORMAT_GROUP) {
1493 			sz = sample->read.group.nr *
1494 			     sizeof(struct sample_read_value);
1495 			result += sz;
1496 		} else {
1497 			result += sizeof(u64);
1498 		}
1499 	}
1500 
1501 	if (type & PERF_SAMPLE_CALLCHAIN) {
1502 		sz = (sample->callchain->nr + 1) * sizeof(u64);
1503 		result += sz;
1504 	}
1505 
1506 	if (type & PERF_SAMPLE_RAW) {
1507 		result += sizeof(u32);
1508 		result += sample->raw_size;
1509 	}
1510 
1511 	if (type & PERF_SAMPLE_BRANCH_STACK) {
1512 		sz = sample->branch_stack->nr * sizeof(struct branch_entry);
1513 		sz += sizeof(u64);
1514 		result += sz;
1515 	}
1516 
1517 	if (type & PERF_SAMPLE_REGS_USER) {
1518 		if (sample->user_regs.abi) {
1519 			result += sizeof(u64);
1520 			sz = hweight_long(sample_regs_user) * sizeof(u64);
1521 			result += sz;
1522 		} else {
1523 			result += sizeof(u64);
1524 		}
1525 	}
1526 
1527 	if (type & PERF_SAMPLE_STACK_USER) {
1528 		sz = sample->user_stack.size;
1529 		result += sizeof(u64);
1530 		if (sz) {
1531 			result += sz;
1532 			result += sizeof(u64);
1533 		}
1534 	}
1535 
1536 	if (type & PERF_SAMPLE_WEIGHT)
1537 		result += sizeof(u64);
1538 
1539 	if (type & PERF_SAMPLE_DATA_SRC)
1540 		result += sizeof(u64);
1541 
1542 	if (type & PERF_SAMPLE_TRANSACTION)
1543 		result += sizeof(u64);
1544 
1545 	return result;
1546 }
1547 
1548 int perf_event__synthesize_sample(union perf_event *event, u64 type,
1549 				  u64 sample_regs_user, u64 read_format,
1550 				  const struct perf_sample *sample,
1551 				  bool swapped)
1552 {
1553 	u64 *array;
1554 	size_t sz;
1555 	/*
1556 	 * used for cross-endian analysis. See git commit 65014ab3
1557 	 * for why this goofiness is needed.
1558 	 */
1559 	union u64_swap u;
1560 
1561 	array = event->sample.array;
1562 
1563 	if (type & PERF_SAMPLE_IDENTIFIER) {
1564 		*array = sample->id;
1565 		array++;
1566 	}
1567 
1568 	if (type & PERF_SAMPLE_IP) {
1569 		*array = sample->ip;
1570 		array++;
1571 	}
1572 
1573 	if (type & PERF_SAMPLE_TID) {
1574 		u.val32[0] = sample->pid;
1575 		u.val32[1] = sample->tid;
1576 		if (swapped) {
1577 			/*
1578 			 * Inverse of what is done in perf_evsel__parse_sample
1579 			 */
1580 			u.val32[0] = bswap_32(u.val32[0]);
1581 			u.val32[1] = bswap_32(u.val32[1]);
1582 			u.val64 = bswap_64(u.val64);
1583 		}
1584 
1585 		*array = u.val64;
1586 		array++;
1587 	}
1588 
1589 	if (type & PERF_SAMPLE_TIME) {
1590 		*array = sample->time;
1591 		array++;
1592 	}
1593 
1594 	if (type & PERF_SAMPLE_ADDR) {
1595 		*array = sample->addr;
1596 		array++;
1597 	}
1598 
1599 	if (type & PERF_SAMPLE_ID) {
1600 		*array = sample->id;
1601 		array++;
1602 	}
1603 
1604 	if (type & PERF_SAMPLE_STREAM_ID) {
1605 		*array = sample->stream_id;
1606 		array++;
1607 	}
1608 
1609 	if (type & PERF_SAMPLE_CPU) {
1610 		u.val32[0] = sample->cpu;
1611 		if (swapped) {
1612 			/*
1613 			 * Inverse of what is done in perf_evsel__parse_sample
1614 			 */
1615 			u.val32[0] = bswap_32(u.val32[0]);
1616 			u.val64 = bswap_64(u.val64);
1617 		}
1618 		*array = u.val64;
1619 		array++;
1620 	}
1621 
1622 	if (type & PERF_SAMPLE_PERIOD) {
1623 		*array = sample->period;
1624 		array++;
1625 	}
1626 
1627 	if (type & PERF_SAMPLE_READ) {
1628 		if (read_format & PERF_FORMAT_GROUP)
1629 			*array = sample->read.group.nr;
1630 		else
1631 			*array = sample->read.one.value;
1632 		array++;
1633 
1634 		if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) {
1635 			*array = sample->read.time_enabled;
1636 			array++;
1637 		}
1638 
1639 		if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) {
1640 			*array = sample->read.time_running;
1641 			array++;
1642 		}
1643 
1644 		/* PERF_FORMAT_ID is forced for PERF_SAMPLE_READ */
1645 		if (read_format & PERF_FORMAT_GROUP) {
1646 			sz = sample->read.group.nr *
1647 			     sizeof(struct sample_read_value);
1648 			memcpy(array, sample->read.group.values, sz);
1649 			array = (void *)array + sz;
1650 		} else {
1651 			*array = sample->read.one.id;
1652 			array++;
1653 		}
1654 	}
1655 
1656 	if (type & PERF_SAMPLE_CALLCHAIN) {
1657 		sz = (sample->callchain->nr + 1) * sizeof(u64);
1658 		memcpy(array, sample->callchain, sz);
1659 		array = (void *)array + sz;
1660 	}
1661 
1662 	if (type & PERF_SAMPLE_RAW) {
1663 		u.val32[0] = sample->raw_size;
1664 		if (WARN_ONCE(swapped,
1665 			      "Endianness of raw data not corrected!\n")) {
1666 			/*
1667 			 * Inverse of what is done in perf_evsel__parse_sample
1668 			 */
1669 			u.val32[0] = bswap_32(u.val32[0]);
1670 			u.val32[1] = bswap_32(u.val32[1]);
1671 			u.val64 = bswap_64(u.val64);
1672 		}
1673 		*array = u.val64;
1674 		array = (void *)array + sizeof(u32);
1675 
1676 		memcpy(array, sample->raw_data, sample->raw_size);
1677 		array = (void *)array + sample->raw_size;
1678 	}
1679 
1680 	if (type & PERF_SAMPLE_BRANCH_STACK) {
1681 		sz = sample->branch_stack->nr * sizeof(struct branch_entry);
1682 		sz += sizeof(u64);
1683 		memcpy(array, sample->branch_stack, sz);
1684 		array = (void *)array + sz;
1685 	}
1686 
1687 	if (type & PERF_SAMPLE_REGS_USER) {
1688 		if (sample->user_regs.abi) {
1689 			*array++ = sample->user_regs.abi;
1690 			sz = hweight_long(sample_regs_user) * sizeof(u64);
1691 			memcpy(array, sample->user_regs.regs, sz);
1692 			array = (void *)array + sz;
1693 		} else {
1694 			*array++ = 0;
1695 		}
1696 	}
1697 
1698 	if (type & PERF_SAMPLE_STACK_USER) {
1699 		sz = sample->user_stack.size;
1700 		*array++ = sz;
1701 		if (sz) {
1702 			memcpy(array, sample->user_stack.data, sz);
1703 			array = (void *)array + sz;
1704 			*array++ = sz;
1705 		}
1706 	}
1707 
1708 	if (type & PERF_SAMPLE_WEIGHT) {
1709 		*array = sample->weight;
1710 		array++;
1711 	}
1712 
1713 	if (type & PERF_SAMPLE_DATA_SRC) {
1714 		*array = sample->data_src;
1715 		array++;
1716 	}
1717 
1718 	if (type & PERF_SAMPLE_TRANSACTION) {
1719 		*array = sample->transaction;
1720 		array++;
1721 	}
1722 
1723 	return 0;
1724 }
1725 
1726 struct format_field *perf_evsel__field(struct perf_evsel *evsel, const char *name)
1727 {
1728 	return pevent_find_field(evsel->tp_format, name);
1729 }
1730 
1731 void *perf_evsel__rawptr(struct perf_evsel *evsel, struct perf_sample *sample,
1732 			 const char *name)
1733 {
1734 	struct format_field *field = perf_evsel__field(evsel, name);
1735 	int offset;
1736 
1737 	if (!field)
1738 		return NULL;
1739 
1740 	offset = field->offset;
1741 
1742 	if (field->flags & FIELD_IS_DYNAMIC) {
1743 		offset = *(int *)(sample->raw_data + field->offset);
1744 		offset &= 0xffff;
1745 	}
1746 
1747 	return sample->raw_data + offset;
1748 }
1749 
1750 u64 perf_evsel__intval(struct perf_evsel *evsel, struct perf_sample *sample,
1751 		       const char *name)
1752 {
1753 	struct format_field *field = perf_evsel__field(evsel, name);
1754 	void *ptr;
1755 	u64 value;
1756 
1757 	if (!field)
1758 		return 0;
1759 
1760 	ptr = sample->raw_data + field->offset;
1761 
1762 	switch (field->size) {
1763 	case 1:
1764 		return *(u8 *)ptr;
1765 	case 2:
1766 		value = *(u16 *)ptr;
1767 		break;
1768 	case 4:
1769 		value = *(u32 *)ptr;
1770 		break;
1771 	case 8:
1772 		value = *(u64 *)ptr;
1773 		break;
1774 	default:
1775 		return 0;
1776 	}
1777 
1778 	if (!evsel->needs_swap)
1779 		return value;
1780 
1781 	switch (field->size) {
1782 	case 2:
1783 		return bswap_16(value);
1784 	case 4:
1785 		return bswap_32(value);
1786 	case 8:
1787 		return bswap_64(value);
1788 	default:
1789 		return 0;
1790 	}
1791 
1792 	return 0;
1793 }
1794 
1795 static int comma_fprintf(FILE *fp, bool *first, const char *fmt, ...)
1796 {
1797 	va_list args;
1798 	int ret = 0;
1799 
1800 	if (!*first) {
1801 		ret += fprintf(fp, ",");
1802 	} else {
1803 		ret += fprintf(fp, ":");
1804 		*first = false;
1805 	}
1806 
1807 	va_start(args, fmt);
1808 	ret += vfprintf(fp, fmt, args);
1809 	va_end(args);
1810 	return ret;
1811 }
1812 
1813 static int __if_fprintf(FILE *fp, bool *first, const char *field, u64 value)
1814 {
1815 	if (value == 0)
1816 		return 0;
1817 
1818 	return comma_fprintf(fp, first, " %s: %" PRIu64, field, value);
1819 }
1820 
1821 #define if_print(field) printed += __if_fprintf(fp, &first, #field, evsel->attr.field)
1822 
1823 struct bit_names {
1824 	int bit;
1825 	const char *name;
1826 };
1827 
1828 static int bits__fprintf(FILE *fp, const char *field, u64 value,
1829 			 struct bit_names *bits, bool *first)
1830 {
1831 	int i = 0, printed = comma_fprintf(fp, first, " %s: ", field);
1832 	bool first_bit = true;
1833 
1834 	do {
1835 		if (value & bits[i].bit) {
1836 			printed += fprintf(fp, "%s%s", first_bit ? "" : "|", bits[i].name);
1837 			first_bit = false;
1838 		}
1839 	} while (bits[++i].name != NULL);
1840 
1841 	return printed;
1842 }
1843 
1844 static int sample_type__fprintf(FILE *fp, bool *first, u64 value)
1845 {
1846 #define bit_name(n) { PERF_SAMPLE_##n, #n }
1847 	struct bit_names bits[] = {
1848 		bit_name(IP), bit_name(TID), bit_name(TIME), bit_name(ADDR),
1849 		bit_name(READ), bit_name(CALLCHAIN), bit_name(ID), bit_name(CPU),
1850 		bit_name(PERIOD), bit_name(STREAM_ID), bit_name(RAW),
1851 		bit_name(BRANCH_STACK), bit_name(REGS_USER), bit_name(STACK_USER),
1852 		bit_name(IDENTIFIER),
1853 		{ .name = NULL, }
1854 	};
1855 #undef bit_name
1856 	return bits__fprintf(fp, "sample_type", value, bits, first);
1857 }
1858 
1859 static int read_format__fprintf(FILE *fp, bool *first, u64 value)
1860 {
1861 #define bit_name(n) { PERF_FORMAT_##n, #n }
1862 	struct bit_names bits[] = {
1863 		bit_name(TOTAL_TIME_ENABLED), bit_name(TOTAL_TIME_RUNNING),
1864 		bit_name(ID), bit_name(GROUP),
1865 		{ .name = NULL, }
1866 	};
1867 #undef bit_name
1868 	return bits__fprintf(fp, "read_format", value, bits, first);
1869 }
1870 
1871 int perf_evsel__fprintf(struct perf_evsel *evsel,
1872 			struct perf_attr_details *details, FILE *fp)
1873 {
1874 	bool first = true;
1875 	int printed = 0;
1876 
1877 	if (details->event_group) {
1878 		struct perf_evsel *pos;
1879 
1880 		if (!perf_evsel__is_group_leader(evsel))
1881 			return 0;
1882 
1883 		if (evsel->nr_members > 1)
1884 			printed += fprintf(fp, "%s{", evsel->group_name ?: "");
1885 
1886 		printed += fprintf(fp, "%s", perf_evsel__name(evsel));
1887 		for_each_group_member(pos, evsel)
1888 			printed += fprintf(fp, ",%s", perf_evsel__name(pos));
1889 
1890 		if (evsel->nr_members > 1)
1891 			printed += fprintf(fp, "}");
1892 		goto out;
1893 	}
1894 
1895 	printed += fprintf(fp, "%s", perf_evsel__name(evsel));
1896 
1897 	if (details->verbose || details->freq) {
1898 		printed += comma_fprintf(fp, &first, " sample_freq=%" PRIu64,
1899 					 (u64)evsel->attr.sample_freq);
1900 	}
1901 
1902 	if (details->verbose) {
1903 		if_print(type);
1904 		if_print(config);
1905 		if_print(config1);
1906 		if_print(config2);
1907 		if_print(size);
1908 		printed += sample_type__fprintf(fp, &first, evsel->attr.sample_type);
1909 		if (evsel->attr.read_format)
1910 			printed += read_format__fprintf(fp, &first, evsel->attr.read_format);
1911 		if_print(disabled);
1912 		if_print(inherit);
1913 		if_print(pinned);
1914 		if_print(exclusive);
1915 		if_print(exclude_user);
1916 		if_print(exclude_kernel);
1917 		if_print(exclude_hv);
1918 		if_print(exclude_idle);
1919 		if_print(mmap);
1920 		if_print(mmap2);
1921 		if_print(comm);
1922 		if_print(freq);
1923 		if_print(inherit_stat);
1924 		if_print(enable_on_exec);
1925 		if_print(task);
1926 		if_print(watermark);
1927 		if_print(precise_ip);
1928 		if_print(mmap_data);
1929 		if_print(sample_id_all);
1930 		if_print(exclude_host);
1931 		if_print(exclude_guest);
1932 		if_print(__reserved_1);
1933 		if_print(wakeup_events);
1934 		if_print(bp_type);
1935 		if_print(branch_sample_type);
1936 	}
1937 out:
1938 	fputc('\n', fp);
1939 	return ++printed;
1940 }
1941 
1942 bool perf_evsel__fallback(struct perf_evsel *evsel, int err,
1943 			  char *msg, size_t msgsize)
1944 {
1945 	if ((err == ENOENT || err == ENXIO || err == ENODEV) &&
1946 	    evsel->attr.type   == PERF_TYPE_HARDWARE &&
1947 	    evsel->attr.config == PERF_COUNT_HW_CPU_CYCLES) {
1948 		/*
1949 		 * If it's cycles then fall back to hrtimer based
1950 		 * cpu-clock-tick sw counter, which is always available even if
1951 		 * no PMU support.
1952 		 *
1953 		 * PPC returns ENXIO until 2.6.37 (behavior changed with commit
1954 		 * b0a873e).
1955 		 */
1956 		scnprintf(msg, msgsize, "%s",
1957 "The cycles event is not supported, trying to fall back to cpu-clock-ticks");
1958 
1959 		evsel->attr.type   = PERF_TYPE_SOFTWARE;
1960 		evsel->attr.config = PERF_COUNT_SW_CPU_CLOCK;
1961 
1962 		zfree(&evsel->name);
1963 		return true;
1964 	}
1965 
1966 	return false;
1967 }
1968 
1969 int perf_evsel__open_strerror(struct perf_evsel *evsel, struct target *target,
1970 			      int err, char *msg, size_t size)
1971 {
1972 	switch (err) {
1973 	case EPERM:
1974 	case EACCES:
1975 		return scnprintf(msg, size,
1976 		 "You may not have permission to collect %sstats.\n"
1977 		 "Consider tweaking /proc/sys/kernel/perf_event_paranoid:\n"
1978 		 " -1 - Not paranoid at all\n"
1979 		 "  0 - Disallow raw tracepoint access for unpriv\n"
1980 		 "  1 - Disallow cpu events for unpriv\n"
1981 		 "  2 - Disallow kernel profiling for unpriv",
1982 				 target->system_wide ? "system-wide " : "");
1983 	case ENOENT:
1984 		return scnprintf(msg, size, "The %s event is not supported.",
1985 				 perf_evsel__name(evsel));
1986 	case EMFILE:
1987 		return scnprintf(msg, size, "%s",
1988 			 "Too many events are opened.\n"
1989 			 "Try again after reducing the number of events.");
1990 	case ENODEV:
1991 		if (target->cpu_list)
1992 			return scnprintf(msg, size, "%s",
1993 	 "No such device - did you specify an out-of-range profile CPU?\n");
1994 		break;
1995 	case EOPNOTSUPP:
1996 		if (evsel->attr.precise_ip)
1997 			return scnprintf(msg, size, "%s",
1998 	"\'precise\' request may not be supported. Try removing 'p' modifier.");
1999 #if defined(__i386__) || defined(__x86_64__)
2000 		if (evsel->attr.type == PERF_TYPE_HARDWARE)
2001 			return scnprintf(msg, size, "%s",
2002 	"No hardware sampling interrupt available.\n"
2003 	"No APIC? If so then you can boot the kernel with the \"lapic\" boot parameter to force-enable it.");
2004 #endif
2005 		break;
2006 	default:
2007 		break;
2008 	}
2009 
2010 	return scnprintf(msg, size,
2011 	"The sys_perf_event_open() syscall returned with %d (%s) for event (%s).  \n"
2012 	"/bin/dmesg may provide additional information.\n"
2013 	"No CONFIG_PERF_EVENTS=y kernel support configured?\n",
2014 			 err, strerror(err), perf_evsel__name(evsel));
2015 }
2016