xref: /openbmc/linux/tools/perf/util/evsel.c (revision 33ac9dba)
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 	bool cloexec;
33 } perf_missing_features;
34 
35 #define FD(e, x, y) (*(int *)xyarray__entry(e->fd, x, y))
36 
37 int __perf_evsel__sample_size(u64 sample_type)
38 {
39 	u64 mask = sample_type & PERF_SAMPLE_MASK;
40 	int size = 0;
41 	int i;
42 
43 	for (i = 0; i < 64; i++) {
44 		if (mask & (1ULL << i))
45 			size++;
46 	}
47 
48 	size *= sizeof(u64);
49 
50 	return size;
51 }
52 
53 /**
54  * __perf_evsel__calc_id_pos - calculate id_pos.
55  * @sample_type: sample type
56  *
57  * This function returns the position of the event id (PERF_SAMPLE_ID or
58  * PERF_SAMPLE_IDENTIFIER) in a sample event i.e. in the array of struct
59  * sample_event.
60  */
61 static int __perf_evsel__calc_id_pos(u64 sample_type)
62 {
63 	int idx = 0;
64 
65 	if (sample_type & PERF_SAMPLE_IDENTIFIER)
66 		return 0;
67 
68 	if (!(sample_type & PERF_SAMPLE_ID))
69 		return -1;
70 
71 	if (sample_type & PERF_SAMPLE_IP)
72 		idx += 1;
73 
74 	if (sample_type & PERF_SAMPLE_TID)
75 		idx += 1;
76 
77 	if (sample_type & PERF_SAMPLE_TIME)
78 		idx += 1;
79 
80 	if (sample_type & PERF_SAMPLE_ADDR)
81 		idx += 1;
82 
83 	return idx;
84 }
85 
86 /**
87  * __perf_evsel__calc_is_pos - calculate is_pos.
88  * @sample_type: sample type
89  *
90  * This function returns the position (counting backwards) of the event id
91  * (PERF_SAMPLE_ID or PERF_SAMPLE_IDENTIFIER) in a non-sample event i.e. if
92  * sample_id_all is used there is an id sample appended to non-sample events.
93  */
94 static int __perf_evsel__calc_is_pos(u64 sample_type)
95 {
96 	int idx = 1;
97 
98 	if (sample_type & PERF_SAMPLE_IDENTIFIER)
99 		return 1;
100 
101 	if (!(sample_type & PERF_SAMPLE_ID))
102 		return -1;
103 
104 	if (sample_type & PERF_SAMPLE_CPU)
105 		idx += 1;
106 
107 	if (sample_type & PERF_SAMPLE_STREAM_ID)
108 		idx += 1;
109 
110 	return idx;
111 }
112 
113 void perf_evsel__calc_id_pos(struct perf_evsel *evsel)
114 {
115 	evsel->id_pos = __perf_evsel__calc_id_pos(evsel->attr.sample_type);
116 	evsel->is_pos = __perf_evsel__calc_is_pos(evsel->attr.sample_type);
117 }
118 
119 void hists__init(struct hists *hists)
120 {
121 	memset(hists, 0, sizeof(*hists));
122 	hists->entries_in_array[0] = hists->entries_in_array[1] = RB_ROOT;
123 	hists->entries_in = &hists->entries_in_array[0];
124 	hists->entries_collapsed = RB_ROOT;
125 	hists->entries = RB_ROOT;
126 	pthread_mutex_init(&hists->lock, NULL);
127 }
128 
129 void __perf_evsel__set_sample_bit(struct perf_evsel *evsel,
130 				  enum perf_event_sample_format bit)
131 {
132 	if (!(evsel->attr.sample_type & bit)) {
133 		evsel->attr.sample_type |= bit;
134 		evsel->sample_size += sizeof(u64);
135 		perf_evsel__calc_id_pos(evsel);
136 	}
137 }
138 
139 void __perf_evsel__reset_sample_bit(struct perf_evsel *evsel,
140 				    enum perf_event_sample_format bit)
141 {
142 	if (evsel->attr.sample_type & bit) {
143 		evsel->attr.sample_type &= ~bit;
144 		evsel->sample_size -= sizeof(u64);
145 		perf_evsel__calc_id_pos(evsel);
146 	}
147 }
148 
149 void perf_evsel__set_sample_id(struct perf_evsel *evsel,
150 			       bool can_sample_identifier)
151 {
152 	if (can_sample_identifier) {
153 		perf_evsel__reset_sample_bit(evsel, ID);
154 		perf_evsel__set_sample_bit(evsel, IDENTIFIER);
155 	} else {
156 		perf_evsel__set_sample_bit(evsel, ID);
157 	}
158 	evsel->attr.read_format |= PERF_FORMAT_ID;
159 }
160 
161 void perf_evsel__init(struct perf_evsel *evsel,
162 		      struct perf_event_attr *attr, int idx)
163 {
164 	evsel->idx	   = idx;
165 	evsel->attr	   = *attr;
166 	evsel->leader	   = evsel;
167 	evsel->unit	   = "";
168 	evsel->scale	   = 1.0;
169 	INIT_LIST_HEAD(&evsel->node);
170 	hists__init(&evsel->hists);
171 	evsel->sample_size = __perf_evsel__sample_size(attr->sample_type);
172 	perf_evsel__calc_id_pos(evsel);
173 }
174 
175 struct perf_evsel *perf_evsel__new_idx(struct perf_event_attr *attr, int idx)
176 {
177 	struct perf_evsel *evsel = zalloc(sizeof(*evsel));
178 
179 	if (evsel != NULL)
180 		perf_evsel__init(evsel, attr, idx);
181 
182 	return evsel;
183 }
184 
185 struct perf_evsel *perf_evsel__newtp_idx(const char *sys, const char *name, int idx)
186 {
187 	struct perf_evsel *evsel = zalloc(sizeof(*evsel));
188 
189 	if (evsel != NULL) {
190 		struct perf_event_attr attr = {
191 			.type	       = PERF_TYPE_TRACEPOINT,
192 			.sample_type   = (PERF_SAMPLE_RAW | PERF_SAMPLE_TIME |
193 					  PERF_SAMPLE_CPU | PERF_SAMPLE_PERIOD),
194 		};
195 
196 		if (asprintf(&evsel->name, "%s:%s", sys, name) < 0)
197 			goto out_free;
198 
199 		evsel->tp_format = trace_event__tp_format(sys, name);
200 		if (evsel->tp_format == NULL)
201 			goto out_free;
202 
203 		event_attr_init(&attr);
204 		attr.config = evsel->tp_format->id;
205 		attr.sample_period = 1;
206 		perf_evsel__init(evsel, &attr, idx);
207 	}
208 
209 	return evsel;
210 
211 out_free:
212 	zfree(&evsel->name);
213 	free(evsel);
214 	return NULL;
215 }
216 
217 const char *perf_evsel__hw_names[PERF_COUNT_HW_MAX] = {
218 	"cycles",
219 	"instructions",
220 	"cache-references",
221 	"cache-misses",
222 	"branches",
223 	"branch-misses",
224 	"bus-cycles",
225 	"stalled-cycles-frontend",
226 	"stalled-cycles-backend",
227 	"ref-cycles",
228 };
229 
230 static const char *__perf_evsel__hw_name(u64 config)
231 {
232 	if (config < PERF_COUNT_HW_MAX && perf_evsel__hw_names[config])
233 		return perf_evsel__hw_names[config];
234 
235 	return "unknown-hardware";
236 }
237 
238 static int perf_evsel__add_modifiers(struct perf_evsel *evsel, char *bf, size_t size)
239 {
240 	int colon = 0, r = 0;
241 	struct perf_event_attr *attr = &evsel->attr;
242 	bool exclude_guest_default = false;
243 
244 #define MOD_PRINT(context, mod)	do {					\
245 		if (!attr->exclude_##context) {				\
246 			if (!colon) colon = ++r;			\
247 			r += scnprintf(bf + r, size - r, "%c", mod);	\
248 		} } while(0)
249 
250 	if (attr->exclude_kernel || attr->exclude_user || attr->exclude_hv) {
251 		MOD_PRINT(kernel, 'k');
252 		MOD_PRINT(user, 'u');
253 		MOD_PRINT(hv, 'h');
254 		exclude_guest_default = true;
255 	}
256 
257 	if (attr->precise_ip) {
258 		if (!colon)
259 			colon = ++r;
260 		r += scnprintf(bf + r, size - r, "%.*s", attr->precise_ip, "ppp");
261 		exclude_guest_default = true;
262 	}
263 
264 	if (attr->exclude_host || attr->exclude_guest == exclude_guest_default) {
265 		MOD_PRINT(host, 'H');
266 		MOD_PRINT(guest, 'G');
267 	}
268 #undef MOD_PRINT
269 	if (colon)
270 		bf[colon - 1] = ':';
271 	return r;
272 }
273 
274 static int perf_evsel__hw_name(struct perf_evsel *evsel, char *bf, size_t size)
275 {
276 	int r = scnprintf(bf, size, "%s", __perf_evsel__hw_name(evsel->attr.config));
277 	return r + perf_evsel__add_modifiers(evsel, bf + r, size - r);
278 }
279 
280 const char *perf_evsel__sw_names[PERF_COUNT_SW_MAX] = {
281 	"cpu-clock",
282 	"task-clock",
283 	"page-faults",
284 	"context-switches",
285 	"cpu-migrations",
286 	"minor-faults",
287 	"major-faults",
288 	"alignment-faults",
289 	"emulation-faults",
290 	"dummy",
291 };
292 
293 static const char *__perf_evsel__sw_name(u64 config)
294 {
295 	if (config < PERF_COUNT_SW_MAX && perf_evsel__sw_names[config])
296 		return perf_evsel__sw_names[config];
297 	return "unknown-software";
298 }
299 
300 static int perf_evsel__sw_name(struct perf_evsel *evsel, char *bf, size_t size)
301 {
302 	int r = scnprintf(bf, size, "%s", __perf_evsel__sw_name(evsel->attr.config));
303 	return r + perf_evsel__add_modifiers(evsel, bf + r, size - r);
304 }
305 
306 static int __perf_evsel__bp_name(char *bf, size_t size, u64 addr, u64 type)
307 {
308 	int r;
309 
310 	r = scnprintf(bf, size, "mem:0x%" PRIx64 ":", addr);
311 
312 	if (type & HW_BREAKPOINT_R)
313 		r += scnprintf(bf + r, size - r, "r");
314 
315 	if (type & HW_BREAKPOINT_W)
316 		r += scnprintf(bf + r, size - r, "w");
317 
318 	if (type & HW_BREAKPOINT_X)
319 		r += scnprintf(bf + r, size - r, "x");
320 
321 	return r;
322 }
323 
324 static int perf_evsel__bp_name(struct perf_evsel *evsel, char *bf, size_t size)
325 {
326 	struct perf_event_attr *attr = &evsel->attr;
327 	int r = __perf_evsel__bp_name(bf, size, attr->bp_addr, attr->bp_type);
328 	return r + perf_evsel__add_modifiers(evsel, bf + r, size - r);
329 }
330 
331 const char *perf_evsel__hw_cache[PERF_COUNT_HW_CACHE_MAX]
332 				[PERF_EVSEL__MAX_ALIASES] = {
333  { "L1-dcache",	"l1-d",		"l1d",		"L1-data",		},
334  { "L1-icache",	"l1-i",		"l1i",		"L1-instruction",	},
335  { "LLC",	"L2",							},
336  { "dTLB",	"d-tlb",	"Data-TLB",				},
337  { "iTLB",	"i-tlb",	"Instruction-TLB",			},
338  { "branch",	"branches",	"bpu",		"btb",		"bpc",	},
339  { "node",								},
340 };
341 
342 const char *perf_evsel__hw_cache_op[PERF_COUNT_HW_CACHE_OP_MAX]
343 				   [PERF_EVSEL__MAX_ALIASES] = {
344  { "load",	"loads",	"read",					},
345  { "store",	"stores",	"write",				},
346  { "prefetch",	"prefetches",	"speculative-read", "speculative-load",	},
347 };
348 
349 const char *perf_evsel__hw_cache_result[PERF_COUNT_HW_CACHE_RESULT_MAX]
350 				       [PERF_EVSEL__MAX_ALIASES] = {
351  { "refs",	"Reference",	"ops",		"access",		},
352  { "misses",	"miss",							},
353 };
354 
355 #define C(x)		PERF_COUNT_HW_CACHE_##x
356 #define CACHE_READ	(1 << C(OP_READ))
357 #define CACHE_WRITE	(1 << C(OP_WRITE))
358 #define CACHE_PREFETCH	(1 << C(OP_PREFETCH))
359 #define COP(x)		(1 << x)
360 
361 /*
362  * cache operartion stat
363  * L1I : Read and prefetch only
364  * ITLB and BPU : Read-only
365  */
366 static unsigned long perf_evsel__hw_cache_stat[C(MAX)] = {
367  [C(L1D)]	= (CACHE_READ | CACHE_WRITE | CACHE_PREFETCH),
368  [C(L1I)]	= (CACHE_READ | CACHE_PREFETCH),
369  [C(LL)]	= (CACHE_READ | CACHE_WRITE | CACHE_PREFETCH),
370  [C(DTLB)]	= (CACHE_READ | CACHE_WRITE | CACHE_PREFETCH),
371  [C(ITLB)]	= (CACHE_READ),
372  [C(BPU)]	= (CACHE_READ),
373  [C(NODE)]	= (CACHE_READ | CACHE_WRITE | CACHE_PREFETCH),
374 };
375 
376 bool perf_evsel__is_cache_op_valid(u8 type, u8 op)
377 {
378 	if (perf_evsel__hw_cache_stat[type] & COP(op))
379 		return true;	/* valid */
380 	else
381 		return false;	/* invalid */
382 }
383 
384 int __perf_evsel__hw_cache_type_op_res_name(u8 type, u8 op, u8 result,
385 					    char *bf, size_t size)
386 {
387 	if (result) {
388 		return scnprintf(bf, size, "%s-%s-%s", perf_evsel__hw_cache[type][0],
389 				 perf_evsel__hw_cache_op[op][0],
390 				 perf_evsel__hw_cache_result[result][0]);
391 	}
392 
393 	return scnprintf(bf, size, "%s-%s", perf_evsel__hw_cache[type][0],
394 			 perf_evsel__hw_cache_op[op][1]);
395 }
396 
397 static int __perf_evsel__hw_cache_name(u64 config, char *bf, size_t size)
398 {
399 	u8 op, result, type = (config >>  0) & 0xff;
400 	const char *err = "unknown-ext-hardware-cache-type";
401 
402 	if (type > PERF_COUNT_HW_CACHE_MAX)
403 		goto out_err;
404 
405 	op = (config >>  8) & 0xff;
406 	err = "unknown-ext-hardware-cache-op";
407 	if (op > PERF_COUNT_HW_CACHE_OP_MAX)
408 		goto out_err;
409 
410 	result = (config >> 16) & 0xff;
411 	err = "unknown-ext-hardware-cache-result";
412 	if (result > PERF_COUNT_HW_CACHE_RESULT_MAX)
413 		goto out_err;
414 
415 	err = "invalid-cache";
416 	if (!perf_evsel__is_cache_op_valid(type, op))
417 		goto out_err;
418 
419 	return __perf_evsel__hw_cache_type_op_res_name(type, op, result, bf, size);
420 out_err:
421 	return scnprintf(bf, size, "%s", err);
422 }
423 
424 static int perf_evsel__hw_cache_name(struct perf_evsel *evsel, char *bf, size_t size)
425 {
426 	int ret = __perf_evsel__hw_cache_name(evsel->attr.config, bf, size);
427 	return ret + perf_evsel__add_modifiers(evsel, bf + ret, size - ret);
428 }
429 
430 static int perf_evsel__raw_name(struct perf_evsel *evsel, char *bf, size_t size)
431 {
432 	int ret = scnprintf(bf, size, "raw 0x%" PRIx64, evsel->attr.config);
433 	return ret + perf_evsel__add_modifiers(evsel, bf + ret, size - ret);
434 }
435 
436 const char *perf_evsel__name(struct perf_evsel *evsel)
437 {
438 	char bf[128];
439 
440 	if (evsel->name)
441 		return evsel->name;
442 
443 	switch (evsel->attr.type) {
444 	case PERF_TYPE_RAW:
445 		perf_evsel__raw_name(evsel, bf, sizeof(bf));
446 		break;
447 
448 	case PERF_TYPE_HARDWARE:
449 		perf_evsel__hw_name(evsel, bf, sizeof(bf));
450 		break;
451 
452 	case PERF_TYPE_HW_CACHE:
453 		perf_evsel__hw_cache_name(evsel, bf, sizeof(bf));
454 		break;
455 
456 	case PERF_TYPE_SOFTWARE:
457 		perf_evsel__sw_name(evsel, bf, sizeof(bf));
458 		break;
459 
460 	case PERF_TYPE_TRACEPOINT:
461 		scnprintf(bf, sizeof(bf), "%s", "unknown tracepoint");
462 		break;
463 
464 	case PERF_TYPE_BREAKPOINT:
465 		perf_evsel__bp_name(evsel, bf, sizeof(bf));
466 		break;
467 
468 	default:
469 		scnprintf(bf, sizeof(bf), "unknown attr type: %d",
470 			  evsel->attr.type);
471 		break;
472 	}
473 
474 	evsel->name = strdup(bf);
475 
476 	return evsel->name ?: "unknown";
477 }
478 
479 const char *perf_evsel__group_name(struct perf_evsel *evsel)
480 {
481 	return evsel->group_name ?: "anon group";
482 }
483 
484 int perf_evsel__group_desc(struct perf_evsel *evsel, char *buf, size_t size)
485 {
486 	int ret;
487 	struct perf_evsel *pos;
488 	const char *group_name = perf_evsel__group_name(evsel);
489 
490 	ret = scnprintf(buf, size, "%s", group_name);
491 
492 	ret += scnprintf(buf + ret, size - ret, " { %s",
493 			 perf_evsel__name(evsel));
494 
495 	for_each_group_member(pos, evsel)
496 		ret += scnprintf(buf + ret, size - ret, ", %s",
497 				 perf_evsel__name(pos));
498 
499 	ret += scnprintf(buf + ret, size - ret, " }");
500 
501 	return ret;
502 }
503 
504 static void
505 perf_evsel__config_callgraph(struct perf_evsel *evsel,
506 			     struct record_opts *opts)
507 {
508 	bool function = perf_evsel__is_function_event(evsel);
509 	struct perf_event_attr *attr = &evsel->attr;
510 
511 	perf_evsel__set_sample_bit(evsel, CALLCHAIN);
512 
513 	if (opts->call_graph == CALLCHAIN_DWARF) {
514 		if (!function) {
515 			perf_evsel__set_sample_bit(evsel, REGS_USER);
516 			perf_evsel__set_sample_bit(evsel, STACK_USER);
517 			attr->sample_regs_user = PERF_REGS_MASK;
518 			attr->sample_stack_user = opts->stack_dump_size;
519 			attr->exclude_callchain_user = 1;
520 		} else {
521 			pr_info("Cannot use DWARF unwind for function trace event,"
522 				" falling back to framepointers.\n");
523 		}
524 	}
525 
526 	if (function) {
527 		pr_info("Disabling user space callchains for function trace event.\n");
528 		attr->exclude_callchain_user = 1;
529 	}
530 }
531 
532 /*
533  * The enable_on_exec/disabled value strategy:
534  *
535  *  1) For any type of traced program:
536  *    - all independent events and group leaders are disabled
537  *    - all group members are enabled
538  *
539  *     Group members are ruled by group leaders. They need to
540  *     be enabled, because the group scheduling relies on that.
541  *
542  *  2) For traced programs executed by perf:
543  *     - all independent events and group leaders have
544  *       enable_on_exec set
545  *     - we don't specifically enable or disable any event during
546  *       the record command
547  *
548  *     Independent events and group leaders are initially disabled
549  *     and get enabled by exec. Group members are ruled by group
550  *     leaders as stated in 1).
551  *
552  *  3) For traced programs attached by perf (pid/tid):
553  *     - we specifically enable or disable all events during
554  *       the record command
555  *
556  *     When attaching events to already running traced we
557  *     enable/disable events specifically, as there's no
558  *     initial traced exec call.
559  */
560 void perf_evsel__config(struct perf_evsel *evsel, struct record_opts *opts)
561 {
562 	struct perf_evsel *leader = evsel->leader;
563 	struct perf_event_attr *attr = &evsel->attr;
564 	int track = !evsel->idx; /* only the first counter needs these */
565 	bool per_cpu = opts->target.default_per_cpu && !opts->target.per_thread;
566 
567 	attr->sample_id_all = perf_missing_features.sample_id_all ? 0 : 1;
568 	attr->inherit	    = !opts->no_inherit;
569 
570 	perf_evsel__set_sample_bit(evsel, IP);
571 	perf_evsel__set_sample_bit(evsel, TID);
572 
573 	if (evsel->sample_read) {
574 		perf_evsel__set_sample_bit(evsel, READ);
575 
576 		/*
577 		 * We need ID even in case of single event, because
578 		 * PERF_SAMPLE_READ process ID specific data.
579 		 */
580 		perf_evsel__set_sample_id(evsel, false);
581 
582 		/*
583 		 * Apply group format only if we belong to group
584 		 * with more than one members.
585 		 */
586 		if (leader->nr_members > 1) {
587 			attr->read_format |= PERF_FORMAT_GROUP;
588 			attr->inherit = 0;
589 		}
590 	}
591 
592 	/*
593 	 * We default some events to have a default interval. But keep
594 	 * it a weak assumption overridable by the user.
595 	 */
596 	if (!attr->sample_period || (opts->user_freq != UINT_MAX ||
597 				     opts->user_interval != ULLONG_MAX)) {
598 		if (opts->freq) {
599 			perf_evsel__set_sample_bit(evsel, PERIOD);
600 			attr->freq		= 1;
601 			attr->sample_freq	= opts->freq;
602 		} else {
603 			attr->sample_period = opts->default_interval;
604 		}
605 	}
606 
607 	/*
608 	 * Disable sampling for all group members other
609 	 * than leader in case leader 'leads' the sampling.
610 	 */
611 	if ((leader != evsel) && leader->sample_read) {
612 		attr->sample_freq   = 0;
613 		attr->sample_period = 0;
614 	}
615 
616 	if (opts->no_samples)
617 		attr->sample_freq = 0;
618 
619 	if (opts->inherit_stat)
620 		attr->inherit_stat = 1;
621 
622 	if (opts->sample_address) {
623 		perf_evsel__set_sample_bit(evsel, ADDR);
624 		attr->mmap_data = track;
625 	}
626 
627 	if (opts->call_graph_enabled && !evsel->no_aux_samples)
628 		perf_evsel__config_callgraph(evsel, opts);
629 
630 	if (target__has_cpu(&opts->target))
631 		perf_evsel__set_sample_bit(evsel, CPU);
632 
633 	if (opts->period)
634 		perf_evsel__set_sample_bit(evsel, PERIOD);
635 
636 	if (!perf_missing_features.sample_id_all &&
637 	    (opts->sample_time || !opts->no_inherit ||
638 	     target__has_cpu(&opts->target) || per_cpu))
639 		perf_evsel__set_sample_bit(evsel, TIME);
640 
641 	if (opts->raw_samples && !evsel->no_aux_samples) {
642 		perf_evsel__set_sample_bit(evsel, TIME);
643 		perf_evsel__set_sample_bit(evsel, RAW);
644 		perf_evsel__set_sample_bit(evsel, CPU);
645 	}
646 
647 	if (opts->sample_address)
648 		perf_evsel__set_sample_bit(evsel, DATA_SRC);
649 
650 	if (opts->no_buffering) {
651 		attr->watermark = 0;
652 		attr->wakeup_events = 1;
653 	}
654 	if (opts->branch_stack && !evsel->no_aux_samples) {
655 		perf_evsel__set_sample_bit(evsel, BRANCH_STACK);
656 		attr->branch_sample_type = opts->branch_stack;
657 	}
658 
659 	if (opts->sample_weight)
660 		perf_evsel__set_sample_bit(evsel, WEIGHT);
661 
662 	attr->mmap  = track;
663 	attr->mmap2 = track && !perf_missing_features.mmap2;
664 	attr->comm  = track;
665 
666 	if (opts->sample_transaction)
667 		perf_evsel__set_sample_bit(evsel, TRANSACTION);
668 
669 	/*
670 	 * XXX see the function comment above
671 	 *
672 	 * Disabling only independent events or group leaders,
673 	 * keeping group members enabled.
674 	 */
675 	if (perf_evsel__is_group_leader(evsel))
676 		attr->disabled = 1;
677 
678 	/*
679 	 * Setting enable_on_exec for independent events and
680 	 * group leaders for traced executed by perf.
681 	 */
682 	if (target__none(&opts->target) && perf_evsel__is_group_leader(evsel) &&
683 		!opts->initial_delay)
684 		attr->enable_on_exec = 1;
685 
686 	if (evsel->immediate) {
687 		attr->disabled = 0;
688 		attr->enable_on_exec = 0;
689 	}
690 }
691 
692 int perf_evsel__alloc_fd(struct perf_evsel *evsel, int ncpus, int nthreads)
693 {
694 	int cpu, thread;
695 	evsel->fd = xyarray__new(ncpus, nthreads, sizeof(int));
696 
697 	if (evsel->fd) {
698 		for (cpu = 0; cpu < ncpus; cpu++) {
699 			for (thread = 0; thread < nthreads; thread++) {
700 				FD(evsel, cpu, thread) = -1;
701 			}
702 		}
703 	}
704 
705 	return evsel->fd != NULL ? 0 : -ENOMEM;
706 }
707 
708 static int perf_evsel__run_ioctl(struct perf_evsel *evsel, int ncpus, int nthreads,
709 			  int ioc,  void *arg)
710 {
711 	int cpu, thread;
712 
713 	for (cpu = 0; cpu < ncpus; cpu++) {
714 		for (thread = 0; thread < nthreads; thread++) {
715 			int fd = FD(evsel, cpu, thread),
716 			    err = ioctl(fd, ioc, arg);
717 
718 			if (err)
719 				return err;
720 		}
721 	}
722 
723 	return 0;
724 }
725 
726 int perf_evsel__set_filter(struct perf_evsel *evsel, int ncpus, int nthreads,
727 			   const char *filter)
728 {
729 	return perf_evsel__run_ioctl(evsel, ncpus, nthreads,
730 				     PERF_EVENT_IOC_SET_FILTER,
731 				     (void *)filter);
732 }
733 
734 int perf_evsel__enable(struct perf_evsel *evsel, int ncpus, int nthreads)
735 {
736 	return perf_evsel__run_ioctl(evsel, ncpus, nthreads,
737 				     PERF_EVENT_IOC_ENABLE,
738 				     0);
739 }
740 
741 int perf_evsel__alloc_id(struct perf_evsel *evsel, int ncpus, int nthreads)
742 {
743 	evsel->sample_id = xyarray__new(ncpus, nthreads, sizeof(struct perf_sample_id));
744 	if (evsel->sample_id == NULL)
745 		return -ENOMEM;
746 
747 	evsel->id = zalloc(ncpus * nthreads * sizeof(u64));
748 	if (evsel->id == NULL) {
749 		xyarray__delete(evsel->sample_id);
750 		evsel->sample_id = NULL;
751 		return -ENOMEM;
752 	}
753 
754 	return 0;
755 }
756 
757 void perf_evsel__reset_counts(struct perf_evsel *evsel, int ncpus)
758 {
759 	memset(evsel->counts, 0, (sizeof(*evsel->counts) +
760 				 (ncpus * sizeof(struct perf_counts_values))));
761 }
762 
763 int perf_evsel__alloc_counts(struct perf_evsel *evsel, int ncpus)
764 {
765 	evsel->counts = zalloc((sizeof(*evsel->counts) +
766 				(ncpus * sizeof(struct perf_counts_values))));
767 	return evsel->counts != NULL ? 0 : -ENOMEM;
768 }
769 
770 void perf_evsel__free_fd(struct perf_evsel *evsel)
771 {
772 	xyarray__delete(evsel->fd);
773 	evsel->fd = NULL;
774 }
775 
776 void perf_evsel__free_id(struct perf_evsel *evsel)
777 {
778 	xyarray__delete(evsel->sample_id);
779 	evsel->sample_id = NULL;
780 	zfree(&evsel->id);
781 }
782 
783 void perf_evsel__close_fd(struct perf_evsel *evsel, int ncpus, int nthreads)
784 {
785 	int cpu, thread;
786 
787 	for (cpu = 0; cpu < ncpus; cpu++)
788 		for (thread = 0; thread < nthreads; ++thread) {
789 			close(FD(evsel, cpu, thread));
790 			FD(evsel, cpu, thread) = -1;
791 		}
792 }
793 
794 void perf_evsel__free_counts(struct perf_evsel *evsel)
795 {
796 	zfree(&evsel->counts);
797 }
798 
799 void perf_evsel__exit(struct perf_evsel *evsel)
800 {
801 	assert(list_empty(&evsel->node));
802 	perf_evsel__free_fd(evsel);
803 	perf_evsel__free_id(evsel);
804 }
805 
806 void perf_evsel__delete(struct perf_evsel *evsel)
807 {
808 	perf_evsel__exit(evsel);
809 	close_cgroup(evsel->cgrp);
810 	zfree(&evsel->group_name);
811 	if (evsel->tp_format)
812 		pevent_free_format(evsel->tp_format);
813 	zfree(&evsel->name);
814 	free(evsel);
815 }
816 
817 static inline void compute_deltas(struct perf_evsel *evsel,
818 				  int cpu,
819 				  struct perf_counts_values *count)
820 {
821 	struct perf_counts_values tmp;
822 
823 	if (!evsel->prev_raw_counts)
824 		return;
825 
826 	if (cpu == -1) {
827 		tmp = evsel->prev_raw_counts->aggr;
828 		evsel->prev_raw_counts->aggr = *count;
829 	} else {
830 		tmp = evsel->prev_raw_counts->cpu[cpu];
831 		evsel->prev_raw_counts->cpu[cpu] = *count;
832 	}
833 
834 	count->val = count->val - tmp.val;
835 	count->ena = count->ena - tmp.ena;
836 	count->run = count->run - tmp.run;
837 }
838 
839 int __perf_evsel__read_on_cpu(struct perf_evsel *evsel,
840 			      int cpu, int thread, bool scale)
841 {
842 	struct perf_counts_values count;
843 	size_t nv = scale ? 3 : 1;
844 
845 	if (FD(evsel, cpu, thread) < 0)
846 		return -EINVAL;
847 
848 	if (evsel->counts == NULL && perf_evsel__alloc_counts(evsel, cpu + 1) < 0)
849 		return -ENOMEM;
850 
851 	if (readn(FD(evsel, cpu, thread), &count, nv * sizeof(u64)) < 0)
852 		return -errno;
853 
854 	compute_deltas(evsel, cpu, &count);
855 
856 	if (scale) {
857 		if (count.run == 0)
858 			count.val = 0;
859 		else if (count.run < count.ena)
860 			count.val = (u64)((double)count.val * count.ena / count.run + 0.5);
861 	} else
862 		count.ena = count.run = 0;
863 
864 	evsel->counts->cpu[cpu] = count;
865 	return 0;
866 }
867 
868 int __perf_evsel__read(struct perf_evsel *evsel,
869 		       int ncpus, int nthreads, bool scale)
870 {
871 	size_t nv = scale ? 3 : 1;
872 	int cpu, thread;
873 	struct perf_counts_values *aggr = &evsel->counts->aggr, count;
874 
875 	aggr->val = aggr->ena = aggr->run = 0;
876 
877 	for (cpu = 0; cpu < ncpus; cpu++) {
878 		for (thread = 0; thread < nthreads; thread++) {
879 			if (FD(evsel, cpu, thread) < 0)
880 				continue;
881 
882 			if (readn(FD(evsel, cpu, thread),
883 				  &count, nv * sizeof(u64)) < 0)
884 				return -errno;
885 
886 			aggr->val += count.val;
887 			if (scale) {
888 				aggr->ena += count.ena;
889 				aggr->run += count.run;
890 			}
891 		}
892 	}
893 
894 	compute_deltas(evsel, -1, aggr);
895 
896 	evsel->counts->scaled = 0;
897 	if (scale) {
898 		if (aggr->run == 0) {
899 			evsel->counts->scaled = -1;
900 			aggr->val = 0;
901 			return 0;
902 		}
903 
904 		if (aggr->run < aggr->ena) {
905 			evsel->counts->scaled = 1;
906 			aggr->val = (u64)((double)aggr->val * aggr->ena / aggr->run + 0.5);
907 		}
908 	} else
909 		aggr->ena = aggr->run = 0;
910 
911 	return 0;
912 }
913 
914 static int get_group_fd(struct perf_evsel *evsel, int cpu, int thread)
915 {
916 	struct perf_evsel *leader = evsel->leader;
917 	int fd;
918 
919 	if (perf_evsel__is_group_leader(evsel))
920 		return -1;
921 
922 	/*
923 	 * Leader must be already processed/open,
924 	 * if not it's a bug.
925 	 */
926 	BUG_ON(!leader->fd);
927 
928 	fd = FD(leader, cpu, thread);
929 	BUG_ON(fd == -1);
930 
931 	return fd;
932 }
933 
934 #define __PRINT_ATTR(fmt, cast, field)  \
935 	fprintf(fp, "  %-19s "fmt"\n", #field, cast attr->field)
936 
937 #define PRINT_ATTR_U32(field)  __PRINT_ATTR("%u" , , field)
938 #define PRINT_ATTR_X32(field)  __PRINT_ATTR("%#x", , field)
939 #define PRINT_ATTR_U64(field)  __PRINT_ATTR("%" PRIu64, (uint64_t), field)
940 #define PRINT_ATTR_X64(field)  __PRINT_ATTR("%#"PRIx64, (uint64_t), field)
941 
942 #define PRINT_ATTR2N(name1, field1, name2, field2)	\
943 	fprintf(fp, "  %-19s %u    %-19s %u\n",		\
944 	name1, attr->field1, name2, attr->field2)
945 
946 #define PRINT_ATTR2(field1, field2) \
947 	PRINT_ATTR2N(#field1, field1, #field2, field2)
948 
949 static size_t perf_event_attr__fprintf(struct perf_event_attr *attr, FILE *fp)
950 {
951 	size_t ret = 0;
952 
953 	ret += fprintf(fp, "%.60s\n", graph_dotted_line);
954 	ret += fprintf(fp, "perf_event_attr:\n");
955 
956 	ret += PRINT_ATTR_U32(type);
957 	ret += PRINT_ATTR_U32(size);
958 	ret += PRINT_ATTR_X64(config);
959 	ret += PRINT_ATTR_U64(sample_period);
960 	ret += PRINT_ATTR_U64(sample_freq);
961 	ret += PRINT_ATTR_X64(sample_type);
962 	ret += PRINT_ATTR_X64(read_format);
963 
964 	ret += PRINT_ATTR2(disabled, inherit);
965 	ret += PRINT_ATTR2(pinned, exclusive);
966 	ret += PRINT_ATTR2(exclude_user, exclude_kernel);
967 	ret += PRINT_ATTR2(exclude_hv, exclude_idle);
968 	ret += PRINT_ATTR2(mmap, comm);
969 	ret += PRINT_ATTR2(mmap2, comm_exec);
970 	ret += PRINT_ATTR2(freq, inherit_stat);
971 	ret += PRINT_ATTR2(enable_on_exec, task);
972 	ret += PRINT_ATTR2(watermark, precise_ip);
973 	ret += PRINT_ATTR2(mmap_data, sample_id_all);
974 	ret += PRINT_ATTR2(exclude_host, exclude_guest);
975 	ret += PRINT_ATTR2N("excl.callchain_kern", exclude_callchain_kernel,
976 			    "excl.callchain_user", exclude_callchain_user);
977 
978 	ret += PRINT_ATTR_U32(wakeup_events);
979 	ret += PRINT_ATTR_U32(wakeup_watermark);
980 	ret += PRINT_ATTR_X32(bp_type);
981 	ret += PRINT_ATTR_X64(bp_addr);
982 	ret += PRINT_ATTR_X64(config1);
983 	ret += PRINT_ATTR_U64(bp_len);
984 	ret += PRINT_ATTR_X64(config2);
985 	ret += PRINT_ATTR_X64(branch_sample_type);
986 	ret += PRINT_ATTR_X64(sample_regs_user);
987 	ret += PRINT_ATTR_U32(sample_stack_user);
988 
989 	ret += fprintf(fp, "%.60s\n", graph_dotted_line);
990 
991 	return ret;
992 }
993 
994 static int __perf_evsel__open(struct perf_evsel *evsel, struct cpu_map *cpus,
995 			      struct thread_map *threads)
996 {
997 	int cpu, thread;
998 	unsigned long flags = PERF_FLAG_FD_CLOEXEC;
999 	int pid = -1, err;
1000 	enum { NO_CHANGE, SET_TO_MAX, INCREASED_MAX } set_rlimit = NO_CHANGE;
1001 
1002 	if (evsel->fd == NULL &&
1003 	    perf_evsel__alloc_fd(evsel, cpus->nr, threads->nr) < 0)
1004 		return -ENOMEM;
1005 
1006 	if (evsel->cgrp) {
1007 		flags |= PERF_FLAG_PID_CGROUP;
1008 		pid = evsel->cgrp->fd;
1009 	}
1010 
1011 fallback_missing_features:
1012 	if (perf_missing_features.cloexec)
1013 		flags &= ~(unsigned long)PERF_FLAG_FD_CLOEXEC;
1014 	if (perf_missing_features.mmap2)
1015 		evsel->attr.mmap2 = 0;
1016 	if (perf_missing_features.exclude_guest)
1017 		evsel->attr.exclude_guest = evsel->attr.exclude_host = 0;
1018 retry_sample_id:
1019 	if (perf_missing_features.sample_id_all)
1020 		evsel->attr.sample_id_all = 0;
1021 
1022 	if (verbose >= 2)
1023 		perf_event_attr__fprintf(&evsel->attr, stderr);
1024 
1025 	for (cpu = 0; cpu < cpus->nr; cpu++) {
1026 
1027 		for (thread = 0; thread < threads->nr; thread++) {
1028 			int group_fd;
1029 
1030 			if (!evsel->cgrp)
1031 				pid = threads->map[thread];
1032 
1033 			group_fd = get_group_fd(evsel, cpu, thread);
1034 retry_open:
1035 			pr_debug2("sys_perf_event_open: pid %d  cpu %d  group_fd %d  flags %#lx\n",
1036 				  pid, cpus->map[cpu], group_fd, flags);
1037 
1038 			FD(evsel, cpu, thread) = sys_perf_event_open(&evsel->attr,
1039 								     pid,
1040 								     cpus->map[cpu],
1041 								     group_fd, flags);
1042 			if (FD(evsel, cpu, thread) < 0) {
1043 				err = -errno;
1044 				pr_debug2("sys_perf_event_open failed, error %d\n",
1045 					  err);
1046 				goto try_fallback;
1047 			}
1048 			set_rlimit = NO_CHANGE;
1049 		}
1050 	}
1051 
1052 	return 0;
1053 
1054 try_fallback:
1055 	/*
1056 	 * perf stat needs between 5 and 22 fds per CPU. When we run out
1057 	 * of them try to increase the limits.
1058 	 */
1059 	if (err == -EMFILE && set_rlimit < INCREASED_MAX) {
1060 		struct rlimit l;
1061 		int old_errno = errno;
1062 
1063 		if (getrlimit(RLIMIT_NOFILE, &l) == 0) {
1064 			if (set_rlimit == NO_CHANGE)
1065 				l.rlim_cur = l.rlim_max;
1066 			else {
1067 				l.rlim_cur = l.rlim_max + 1000;
1068 				l.rlim_max = l.rlim_cur;
1069 			}
1070 			if (setrlimit(RLIMIT_NOFILE, &l) == 0) {
1071 				set_rlimit++;
1072 				errno = old_errno;
1073 				goto retry_open;
1074 			}
1075 		}
1076 		errno = old_errno;
1077 	}
1078 
1079 	if (err != -EINVAL || cpu > 0 || thread > 0)
1080 		goto out_close;
1081 
1082 	if (!perf_missing_features.cloexec && (flags & PERF_FLAG_FD_CLOEXEC)) {
1083 		perf_missing_features.cloexec = true;
1084 		goto fallback_missing_features;
1085 	} else if (!perf_missing_features.mmap2 && evsel->attr.mmap2) {
1086 		perf_missing_features.mmap2 = true;
1087 		goto fallback_missing_features;
1088 	} else if (!perf_missing_features.exclude_guest &&
1089 		   (evsel->attr.exclude_guest || evsel->attr.exclude_host)) {
1090 		perf_missing_features.exclude_guest = true;
1091 		goto fallback_missing_features;
1092 	} else if (!perf_missing_features.sample_id_all) {
1093 		perf_missing_features.sample_id_all = true;
1094 		goto retry_sample_id;
1095 	}
1096 
1097 out_close:
1098 	do {
1099 		while (--thread >= 0) {
1100 			close(FD(evsel, cpu, thread));
1101 			FD(evsel, cpu, thread) = -1;
1102 		}
1103 		thread = threads->nr;
1104 	} while (--cpu >= 0);
1105 	return err;
1106 }
1107 
1108 void perf_evsel__close(struct perf_evsel *evsel, int ncpus, int nthreads)
1109 {
1110 	if (evsel->fd == NULL)
1111 		return;
1112 
1113 	perf_evsel__close_fd(evsel, ncpus, nthreads);
1114 	perf_evsel__free_fd(evsel);
1115 }
1116 
1117 static struct {
1118 	struct cpu_map map;
1119 	int cpus[1];
1120 } empty_cpu_map = {
1121 	.map.nr	= 1,
1122 	.cpus	= { -1, },
1123 };
1124 
1125 static struct {
1126 	struct thread_map map;
1127 	int threads[1];
1128 } empty_thread_map = {
1129 	.map.nr	 = 1,
1130 	.threads = { -1, },
1131 };
1132 
1133 int perf_evsel__open(struct perf_evsel *evsel, struct cpu_map *cpus,
1134 		     struct thread_map *threads)
1135 {
1136 	if (cpus == NULL) {
1137 		/* Work around old compiler warnings about strict aliasing */
1138 		cpus = &empty_cpu_map.map;
1139 	}
1140 
1141 	if (threads == NULL)
1142 		threads = &empty_thread_map.map;
1143 
1144 	return __perf_evsel__open(evsel, cpus, threads);
1145 }
1146 
1147 int perf_evsel__open_per_cpu(struct perf_evsel *evsel,
1148 			     struct cpu_map *cpus)
1149 {
1150 	return __perf_evsel__open(evsel, cpus, &empty_thread_map.map);
1151 }
1152 
1153 int perf_evsel__open_per_thread(struct perf_evsel *evsel,
1154 				struct thread_map *threads)
1155 {
1156 	return __perf_evsel__open(evsel, &empty_cpu_map.map, threads);
1157 }
1158 
1159 static int perf_evsel__parse_id_sample(const struct perf_evsel *evsel,
1160 				       const union perf_event *event,
1161 				       struct perf_sample *sample)
1162 {
1163 	u64 type = evsel->attr.sample_type;
1164 	const u64 *array = event->sample.array;
1165 	bool swapped = evsel->needs_swap;
1166 	union u64_swap u;
1167 
1168 	array += ((event->header.size -
1169 		   sizeof(event->header)) / sizeof(u64)) - 1;
1170 
1171 	if (type & PERF_SAMPLE_IDENTIFIER) {
1172 		sample->id = *array;
1173 		array--;
1174 	}
1175 
1176 	if (type & PERF_SAMPLE_CPU) {
1177 		u.val64 = *array;
1178 		if (swapped) {
1179 			/* undo swap of u64, then swap on individual u32s */
1180 			u.val64 = bswap_64(u.val64);
1181 			u.val32[0] = bswap_32(u.val32[0]);
1182 		}
1183 
1184 		sample->cpu = u.val32[0];
1185 		array--;
1186 	}
1187 
1188 	if (type & PERF_SAMPLE_STREAM_ID) {
1189 		sample->stream_id = *array;
1190 		array--;
1191 	}
1192 
1193 	if (type & PERF_SAMPLE_ID) {
1194 		sample->id = *array;
1195 		array--;
1196 	}
1197 
1198 	if (type & PERF_SAMPLE_TIME) {
1199 		sample->time = *array;
1200 		array--;
1201 	}
1202 
1203 	if (type & PERF_SAMPLE_TID) {
1204 		u.val64 = *array;
1205 		if (swapped) {
1206 			/* undo swap of u64, then swap on individual u32s */
1207 			u.val64 = bswap_64(u.val64);
1208 			u.val32[0] = bswap_32(u.val32[0]);
1209 			u.val32[1] = bswap_32(u.val32[1]);
1210 		}
1211 
1212 		sample->pid = u.val32[0];
1213 		sample->tid = u.val32[1];
1214 		array--;
1215 	}
1216 
1217 	return 0;
1218 }
1219 
1220 static inline bool overflow(const void *endp, u16 max_size, const void *offset,
1221 			    u64 size)
1222 {
1223 	return size > max_size || offset + size > endp;
1224 }
1225 
1226 #define OVERFLOW_CHECK(offset, size, max_size)				\
1227 	do {								\
1228 		if (overflow(endp, (max_size), (offset), (size)))	\
1229 			return -EFAULT;					\
1230 	} while (0)
1231 
1232 #define OVERFLOW_CHECK_u64(offset) \
1233 	OVERFLOW_CHECK(offset, sizeof(u64), sizeof(u64))
1234 
1235 int perf_evsel__parse_sample(struct perf_evsel *evsel, union perf_event *event,
1236 			     struct perf_sample *data)
1237 {
1238 	u64 type = evsel->attr.sample_type;
1239 	bool swapped = evsel->needs_swap;
1240 	const u64 *array;
1241 	u16 max_size = event->header.size;
1242 	const void *endp = (void *)event + max_size;
1243 	u64 sz;
1244 
1245 	/*
1246 	 * used for cross-endian analysis. See git commit 65014ab3
1247 	 * for why this goofiness is needed.
1248 	 */
1249 	union u64_swap u;
1250 
1251 	memset(data, 0, sizeof(*data));
1252 	data->cpu = data->pid = data->tid = -1;
1253 	data->stream_id = data->id = data->time = -1ULL;
1254 	data->period = evsel->attr.sample_period;
1255 	data->weight = 0;
1256 
1257 	if (event->header.type != PERF_RECORD_SAMPLE) {
1258 		if (!evsel->attr.sample_id_all)
1259 			return 0;
1260 		return perf_evsel__parse_id_sample(evsel, event, data);
1261 	}
1262 
1263 	array = event->sample.array;
1264 
1265 	/*
1266 	 * The evsel's sample_size is based on PERF_SAMPLE_MASK which includes
1267 	 * up to PERF_SAMPLE_PERIOD.  After that overflow() must be used to
1268 	 * check the format does not go past the end of the event.
1269 	 */
1270 	if (evsel->sample_size + sizeof(event->header) > event->header.size)
1271 		return -EFAULT;
1272 
1273 	data->id = -1ULL;
1274 	if (type & PERF_SAMPLE_IDENTIFIER) {
1275 		data->id = *array;
1276 		array++;
1277 	}
1278 
1279 	if (type & PERF_SAMPLE_IP) {
1280 		data->ip = *array;
1281 		array++;
1282 	}
1283 
1284 	if (type & PERF_SAMPLE_TID) {
1285 		u.val64 = *array;
1286 		if (swapped) {
1287 			/* undo swap of u64, then swap on individual u32s */
1288 			u.val64 = bswap_64(u.val64);
1289 			u.val32[0] = bswap_32(u.val32[0]);
1290 			u.val32[1] = bswap_32(u.val32[1]);
1291 		}
1292 
1293 		data->pid = u.val32[0];
1294 		data->tid = u.val32[1];
1295 		array++;
1296 	}
1297 
1298 	if (type & PERF_SAMPLE_TIME) {
1299 		data->time = *array;
1300 		array++;
1301 	}
1302 
1303 	data->addr = 0;
1304 	if (type & PERF_SAMPLE_ADDR) {
1305 		data->addr = *array;
1306 		array++;
1307 	}
1308 
1309 	if (type & PERF_SAMPLE_ID) {
1310 		data->id = *array;
1311 		array++;
1312 	}
1313 
1314 	if (type & PERF_SAMPLE_STREAM_ID) {
1315 		data->stream_id = *array;
1316 		array++;
1317 	}
1318 
1319 	if (type & PERF_SAMPLE_CPU) {
1320 
1321 		u.val64 = *array;
1322 		if (swapped) {
1323 			/* undo swap of u64, then swap on individual u32s */
1324 			u.val64 = bswap_64(u.val64);
1325 			u.val32[0] = bswap_32(u.val32[0]);
1326 		}
1327 
1328 		data->cpu = u.val32[0];
1329 		array++;
1330 	}
1331 
1332 	if (type & PERF_SAMPLE_PERIOD) {
1333 		data->period = *array;
1334 		array++;
1335 	}
1336 
1337 	if (type & PERF_SAMPLE_READ) {
1338 		u64 read_format = evsel->attr.read_format;
1339 
1340 		OVERFLOW_CHECK_u64(array);
1341 		if (read_format & PERF_FORMAT_GROUP)
1342 			data->read.group.nr = *array;
1343 		else
1344 			data->read.one.value = *array;
1345 
1346 		array++;
1347 
1348 		if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) {
1349 			OVERFLOW_CHECK_u64(array);
1350 			data->read.time_enabled = *array;
1351 			array++;
1352 		}
1353 
1354 		if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) {
1355 			OVERFLOW_CHECK_u64(array);
1356 			data->read.time_running = *array;
1357 			array++;
1358 		}
1359 
1360 		/* PERF_FORMAT_ID is forced for PERF_SAMPLE_READ */
1361 		if (read_format & PERF_FORMAT_GROUP) {
1362 			const u64 max_group_nr = UINT64_MAX /
1363 					sizeof(struct sample_read_value);
1364 
1365 			if (data->read.group.nr > max_group_nr)
1366 				return -EFAULT;
1367 			sz = data->read.group.nr *
1368 			     sizeof(struct sample_read_value);
1369 			OVERFLOW_CHECK(array, sz, max_size);
1370 			data->read.group.values =
1371 					(struct sample_read_value *)array;
1372 			array = (void *)array + sz;
1373 		} else {
1374 			OVERFLOW_CHECK_u64(array);
1375 			data->read.one.id = *array;
1376 			array++;
1377 		}
1378 	}
1379 
1380 	if (type & PERF_SAMPLE_CALLCHAIN) {
1381 		const u64 max_callchain_nr = UINT64_MAX / sizeof(u64);
1382 
1383 		OVERFLOW_CHECK_u64(array);
1384 		data->callchain = (struct ip_callchain *)array++;
1385 		if (data->callchain->nr > max_callchain_nr)
1386 			return -EFAULT;
1387 		sz = data->callchain->nr * sizeof(u64);
1388 		OVERFLOW_CHECK(array, sz, max_size);
1389 		array = (void *)array + sz;
1390 	}
1391 
1392 	if (type & PERF_SAMPLE_RAW) {
1393 		OVERFLOW_CHECK_u64(array);
1394 		u.val64 = *array;
1395 		if (WARN_ONCE(swapped,
1396 			      "Endianness of raw data not corrected!\n")) {
1397 			/* undo swap of u64, then swap on individual u32s */
1398 			u.val64 = bswap_64(u.val64);
1399 			u.val32[0] = bswap_32(u.val32[0]);
1400 			u.val32[1] = bswap_32(u.val32[1]);
1401 		}
1402 		data->raw_size = u.val32[0];
1403 		array = (void *)array + sizeof(u32);
1404 
1405 		OVERFLOW_CHECK(array, data->raw_size, max_size);
1406 		data->raw_data = (void *)array;
1407 		array = (void *)array + data->raw_size;
1408 	}
1409 
1410 	if (type & PERF_SAMPLE_BRANCH_STACK) {
1411 		const u64 max_branch_nr = UINT64_MAX /
1412 					  sizeof(struct branch_entry);
1413 
1414 		OVERFLOW_CHECK_u64(array);
1415 		data->branch_stack = (struct branch_stack *)array++;
1416 
1417 		if (data->branch_stack->nr > max_branch_nr)
1418 			return -EFAULT;
1419 		sz = data->branch_stack->nr * sizeof(struct branch_entry);
1420 		OVERFLOW_CHECK(array, sz, max_size);
1421 		array = (void *)array + sz;
1422 	}
1423 
1424 	if (type & PERF_SAMPLE_REGS_USER) {
1425 		OVERFLOW_CHECK_u64(array);
1426 		data->user_regs.abi = *array;
1427 		array++;
1428 
1429 		if (data->user_regs.abi) {
1430 			u64 mask = evsel->attr.sample_regs_user;
1431 
1432 			sz = hweight_long(mask) * sizeof(u64);
1433 			OVERFLOW_CHECK(array, sz, max_size);
1434 			data->user_regs.mask = mask;
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 			if (WARN_ONCE(data->user_stack.size > sz,
1456 				      "user stack dump failure\n"))
1457 				return -EFAULT;
1458 		}
1459 	}
1460 
1461 	data->weight = 0;
1462 	if (type & PERF_SAMPLE_WEIGHT) {
1463 		OVERFLOW_CHECK_u64(array);
1464 		data->weight = *array;
1465 		array++;
1466 	}
1467 
1468 	data->data_src = PERF_MEM_DATA_SRC_NONE;
1469 	if (type & PERF_SAMPLE_DATA_SRC) {
1470 		OVERFLOW_CHECK_u64(array);
1471 		data->data_src = *array;
1472 		array++;
1473 	}
1474 
1475 	data->transaction = 0;
1476 	if (type & PERF_SAMPLE_TRANSACTION) {
1477 		OVERFLOW_CHECK_u64(array);
1478 		data->transaction = *array;
1479 		array++;
1480 	}
1481 
1482 	return 0;
1483 }
1484 
1485 size_t perf_event__sample_event_size(const struct perf_sample *sample, u64 type,
1486 				     u64 read_format)
1487 {
1488 	size_t sz, result = sizeof(struct sample_event);
1489 
1490 	if (type & PERF_SAMPLE_IDENTIFIER)
1491 		result += sizeof(u64);
1492 
1493 	if (type & PERF_SAMPLE_IP)
1494 		result += sizeof(u64);
1495 
1496 	if (type & PERF_SAMPLE_TID)
1497 		result += sizeof(u64);
1498 
1499 	if (type & PERF_SAMPLE_TIME)
1500 		result += sizeof(u64);
1501 
1502 	if (type & PERF_SAMPLE_ADDR)
1503 		result += sizeof(u64);
1504 
1505 	if (type & PERF_SAMPLE_ID)
1506 		result += sizeof(u64);
1507 
1508 	if (type & PERF_SAMPLE_STREAM_ID)
1509 		result += sizeof(u64);
1510 
1511 	if (type & PERF_SAMPLE_CPU)
1512 		result += sizeof(u64);
1513 
1514 	if (type & PERF_SAMPLE_PERIOD)
1515 		result += sizeof(u64);
1516 
1517 	if (type & PERF_SAMPLE_READ) {
1518 		result += sizeof(u64);
1519 		if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED)
1520 			result += sizeof(u64);
1521 		if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING)
1522 			result += sizeof(u64);
1523 		/* PERF_FORMAT_ID is forced for PERF_SAMPLE_READ */
1524 		if (read_format & PERF_FORMAT_GROUP) {
1525 			sz = sample->read.group.nr *
1526 			     sizeof(struct sample_read_value);
1527 			result += sz;
1528 		} else {
1529 			result += sizeof(u64);
1530 		}
1531 	}
1532 
1533 	if (type & PERF_SAMPLE_CALLCHAIN) {
1534 		sz = (sample->callchain->nr + 1) * sizeof(u64);
1535 		result += sz;
1536 	}
1537 
1538 	if (type & PERF_SAMPLE_RAW) {
1539 		result += sizeof(u32);
1540 		result += sample->raw_size;
1541 	}
1542 
1543 	if (type & PERF_SAMPLE_BRANCH_STACK) {
1544 		sz = sample->branch_stack->nr * sizeof(struct branch_entry);
1545 		sz += sizeof(u64);
1546 		result += sz;
1547 	}
1548 
1549 	if (type & PERF_SAMPLE_REGS_USER) {
1550 		if (sample->user_regs.abi) {
1551 			result += sizeof(u64);
1552 			sz = hweight_long(sample->user_regs.mask) * sizeof(u64);
1553 			result += sz;
1554 		} else {
1555 			result += sizeof(u64);
1556 		}
1557 	}
1558 
1559 	if (type & PERF_SAMPLE_STACK_USER) {
1560 		sz = sample->user_stack.size;
1561 		result += sizeof(u64);
1562 		if (sz) {
1563 			result += sz;
1564 			result += sizeof(u64);
1565 		}
1566 	}
1567 
1568 	if (type & PERF_SAMPLE_WEIGHT)
1569 		result += sizeof(u64);
1570 
1571 	if (type & PERF_SAMPLE_DATA_SRC)
1572 		result += sizeof(u64);
1573 
1574 	if (type & PERF_SAMPLE_TRANSACTION)
1575 		result += sizeof(u64);
1576 
1577 	return result;
1578 }
1579 
1580 int perf_event__synthesize_sample(union perf_event *event, u64 type,
1581 				  u64 read_format,
1582 				  const struct perf_sample *sample,
1583 				  bool swapped)
1584 {
1585 	u64 *array;
1586 	size_t sz;
1587 	/*
1588 	 * used for cross-endian analysis. See git commit 65014ab3
1589 	 * for why this goofiness is needed.
1590 	 */
1591 	union u64_swap u;
1592 
1593 	array = event->sample.array;
1594 
1595 	if (type & PERF_SAMPLE_IDENTIFIER) {
1596 		*array = sample->id;
1597 		array++;
1598 	}
1599 
1600 	if (type & PERF_SAMPLE_IP) {
1601 		*array = sample->ip;
1602 		array++;
1603 	}
1604 
1605 	if (type & PERF_SAMPLE_TID) {
1606 		u.val32[0] = sample->pid;
1607 		u.val32[1] = sample->tid;
1608 		if (swapped) {
1609 			/*
1610 			 * Inverse of what is done in perf_evsel__parse_sample
1611 			 */
1612 			u.val32[0] = bswap_32(u.val32[0]);
1613 			u.val32[1] = bswap_32(u.val32[1]);
1614 			u.val64 = bswap_64(u.val64);
1615 		}
1616 
1617 		*array = u.val64;
1618 		array++;
1619 	}
1620 
1621 	if (type & PERF_SAMPLE_TIME) {
1622 		*array = sample->time;
1623 		array++;
1624 	}
1625 
1626 	if (type & PERF_SAMPLE_ADDR) {
1627 		*array = sample->addr;
1628 		array++;
1629 	}
1630 
1631 	if (type & PERF_SAMPLE_ID) {
1632 		*array = sample->id;
1633 		array++;
1634 	}
1635 
1636 	if (type & PERF_SAMPLE_STREAM_ID) {
1637 		*array = sample->stream_id;
1638 		array++;
1639 	}
1640 
1641 	if (type & PERF_SAMPLE_CPU) {
1642 		u.val32[0] = sample->cpu;
1643 		if (swapped) {
1644 			/*
1645 			 * Inverse of what is done in perf_evsel__parse_sample
1646 			 */
1647 			u.val32[0] = bswap_32(u.val32[0]);
1648 			u.val64 = bswap_64(u.val64);
1649 		}
1650 		*array = u.val64;
1651 		array++;
1652 	}
1653 
1654 	if (type & PERF_SAMPLE_PERIOD) {
1655 		*array = sample->period;
1656 		array++;
1657 	}
1658 
1659 	if (type & PERF_SAMPLE_READ) {
1660 		if (read_format & PERF_FORMAT_GROUP)
1661 			*array = sample->read.group.nr;
1662 		else
1663 			*array = sample->read.one.value;
1664 		array++;
1665 
1666 		if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) {
1667 			*array = sample->read.time_enabled;
1668 			array++;
1669 		}
1670 
1671 		if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) {
1672 			*array = sample->read.time_running;
1673 			array++;
1674 		}
1675 
1676 		/* PERF_FORMAT_ID is forced for PERF_SAMPLE_READ */
1677 		if (read_format & PERF_FORMAT_GROUP) {
1678 			sz = sample->read.group.nr *
1679 			     sizeof(struct sample_read_value);
1680 			memcpy(array, sample->read.group.values, sz);
1681 			array = (void *)array + sz;
1682 		} else {
1683 			*array = sample->read.one.id;
1684 			array++;
1685 		}
1686 	}
1687 
1688 	if (type & PERF_SAMPLE_CALLCHAIN) {
1689 		sz = (sample->callchain->nr + 1) * sizeof(u64);
1690 		memcpy(array, sample->callchain, sz);
1691 		array = (void *)array + sz;
1692 	}
1693 
1694 	if (type & PERF_SAMPLE_RAW) {
1695 		u.val32[0] = sample->raw_size;
1696 		if (WARN_ONCE(swapped,
1697 			      "Endianness of raw data not corrected!\n")) {
1698 			/*
1699 			 * Inverse of what is done in perf_evsel__parse_sample
1700 			 */
1701 			u.val32[0] = bswap_32(u.val32[0]);
1702 			u.val32[1] = bswap_32(u.val32[1]);
1703 			u.val64 = bswap_64(u.val64);
1704 		}
1705 		*array = u.val64;
1706 		array = (void *)array + sizeof(u32);
1707 
1708 		memcpy(array, sample->raw_data, sample->raw_size);
1709 		array = (void *)array + sample->raw_size;
1710 	}
1711 
1712 	if (type & PERF_SAMPLE_BRANCH_STACK) {
1713 		sz = sample->branch_stack->nr * sizeof(struct branch_entry);
1714 		sz += sizeof(u64);
1715 		memcpy(array, sample->branch_stack, sz);
1716 		array = (void *)array + sz;
1717 	}
1718 
1719 	if (type & PERF_SAMPLE_REGS_USER) {
1720 		if (sample->user_regs.abi) {
1721 			*array++ = sample->user_regs.abi;
1722 			sz = hweight_long(sample->user_regs.mask) * sizeof(u64);
1723 			memcpy(array, sample->user_regs.regs, sz);
1724 			array = (void *)array + sz;
1725 		} else {
1726 			*array++ = 0;
1727 		}
1728 	}
1729 
1730 	if (type & PERF_SAMPLE_STACK_USER) {
1731 		sz = sample->user_stack.size;
1732 		*array++ = sz;
1733 		if (sz) {
1734 			memcpy(array, sample->user_stack.data, sz);
1735 			array = (void *)array + sz;
1736 			*array++ = sz;
1737 		}
1738 	}
1739 
1740 	if (type & PERF_SAMPLE_WEIGHT) {
1741 		*array = sample->weight;
1742 		array++;
1743 	}
1744 
1745 	if (type & PERF_SAMPLE_DATA_SRC) {
1746 		*array = sample->data_src;
1747 		array++;
1748 	}
1749 
1750 	if (type & PERF_SAMPLE_TRANSACTION) {
1751 		*array = sample->transaction;
1752 		array++;
1753 	}
1754 
1755 	return 0;
1756 }
1757 
1758 struct format_field *perf_evsel__field(struct perf_evsel *evsel, const char *name)
1759 {
1760 	return pevent_find_field(evsel->tp_format, name);
1761 }
1762 
1763 void *perf_evsel__rawptr(struct perf_evsel *evsel, struct perf_sample *sample,
1764 			 const char *name)
1765 {
1766 	struct format_field *field = perf_evsel__field(evsel, name);
1767 	int offset;
1768 
1769 	if (!field)
1770 		return NULL;
1771 
1772 	offset = field->offset;
1773 
1774 	if (field->flags & FIELD_IS_DYNAMIC) {
1775 		offset = *(int *)(sample->raw_data + field->offset);
1776 		offset &= 0xffff;
1777 	}
1778 
1779 	return sample->raw_data + offset;
1780 }
1781 
1782 u64 perf_evsel__intval(struct perf_evsel *evsel, struct perf_sample *sample,
1783 		       const char *name)
1784 {
1785 	struct format_field *field = perf_evsel__field(evsel, name);
1786 	void *ptr;
1787 	u64 value;
1788 
1789 	if (!field)
1790 		return 0;
1791 
1792 	ptr = sample->raw_data + field->offset;
1793 
1794 	switch (field->size) {
1795 	case 1:
1796 		return *(u8 *)ptr;
1797 	case 2:
1798 		value = *(u16 *)ptr;
1799 		break;
1800 	case 4:
1801 		value = *(u32 *)ptr;
1802 		break;
1803 	case 8:
1804 		value = *(u64 *)ptr;
1805 		break;
1806 	default:
1807 		return 0;
1808 	}
1809 
1810 	if (!evsel->needs_swap)
1811 		return value;
1812 
1813 	switch (field->size) {
1814 	case 2:
1815 		return bswap_16(value);
1816 	case 4:
1817 		return bswap_32(value);
1818 	case 8:
1819 		return bswap_64(value);
1820 	default:
1821 		return 0;
1822 	}
1823 
1824 	return 0;
1825 }
1826 
1827 static int comma_fprintf(FILE *fp, bool *first, const char *fmt, ...)
1828 {
1829 	va_list args;
1830 	int ret = 0;
1831 
1832 	if (!*first) {
1833 		ret += fprintf(fp, ",");
1834 	} else {
1835 		ret += fprintf(fp, ":");
1836 		*first = false;
1837 	}
1838 
1839 	va_start(args, fmt);
1840 	ret += vfprintf(fp, fmt, args);
1841 	va_end(args);
1842 	return ret;
1843 }
1844 
1845 static int __if_fprintf(FILE *fp, bool *first, const char *field, u64 value)
1846 {
1847 	if (value == 0)
1848 		return 0;
1849 
1850 	return comma_fprintf(fp, first, " %s: %" PRIu64, field, value);
1851 }
1852 
1853 #define if_print(field) printed += __if_fprintf(fp, &first, #field, evsel->attr.field)
1854 
1855 struct bit_names {
1856 	int bit;
1857 	const char *name;
1858 };
1859 
1860 static int bits__fprintf(FILE *fp, const char *field, u64 value,
1861 			 struct bit_names *bits, bool *first)
1862 {
1863 	int i = 0, printed = comma_fprintf(fp, first, " %s: ", field);
1864 	bool first_bit = true;
1865 
1866 	do {
1867 		if (value & bits[i].bit) {
1868 			printed += fprintf(fp, "%s%s", first_bit ? "" : "|", bits[i].name);
1869 			first_bit = false;
1870 		}
1871 	} while (bits[++i].name != NULL);
1872 
1873 	return printed;
1874 }
1875 
1876 static int sample_type__fprintf(FILE *fp, bool *first, u64 value)
1877 {
1878 #define bit_name(n) { PERF_SAMPLE_##n, #n }
1879 	struct bit_names bits[] = {
1880 		bit_name(IP), bit_name(TID), bit_name(TIME), bit_name(ADDR),
1881 		bit_name(READ), bit_name(CALLCHAIN), bit_name(ID), bit_name(CPU),
1882 		bit_name(PERIOD), bit_name(STREAM_ID), bit_name(RAW),
1883 		bit_name(BRANCH_STACK), bit_name(REGS_USER), bit_name(STACK_USER),
1884 		bit_name(IDENTIFIER),
1885 		{ .name = NULL, }
1886 	};
1887 #undef bit_name
1888 	return bits__fprintf(fp, "sample_type", value, bits, first);
1889 }
1890 
1891 static int read_format__fprintf(FILE *fp, bool *first, u64 value)
1892 {
1893 #define bit_name(n) { PERF_FORMAT_##n, #n }
1894 	struct bit_names bits[] = {
1895 		bit_name(TOTAL_TIME_ENABLED), bit_name(TOTAL_TIME_RUNNING),
1896 		bit_name(ID), bit_name(GROUP),
1897 		{ .name = NULL, }
1898 	};
1899 #undef bit_name
1900 	return bits__fprintf(fp, "read_format", value, bits, first);
1901 }
1902 
1903 int perf_evsel__fprintf(struct perf_evsel *evsel,
1904 			struct perf_attr_details *details, FILE *fp)
1905 {
1906 	bool first = true;
1907 	int printed = 0;
1908 
1909 	if (details->event_group) {
1910 		struct perf_evsel *pos;
1911 
1912 		if (!perf_evsel__is_group_leader(evsel))
1913 			return 0;
1914 
1915 		if (evsel->nr_members > 1)
1916 			printed += fprintf(fp, "%s{", evsel->group_name ?: "");
1917 
1918 		printed += fprintf(fp, "%s", perf_evsel__name(evsel));
1919 		for_each_group_member(pos, evsel)
1920 			printed += fprintf(fp, ",%s", perf_evsel__name(pos));
1921 
1922 		if (evsel->nr_members > 1)
1923 			printed += fprintf(fp, "}");
1924 		goto out;
1925 	}
1926 
1927 	printed += fprintf(fp, "%s", perf_evsel__name(evsel));
1928 
1929 	if (details->verbose || details->freq) {
1930 		printed += comma_fprintf(fp, &first, " sample_freq=%" PRIu64,
1931 					 (u64)evsel->attr.sample_freq);
1932 	}
1933 
1934 	if (details->verbose) {
1935 		if_print(type);
1936 		if_print(config);
1937 		if_print(config1);
1938 		if_print(config2);
1939 		if_print(size);
1940 		printed += sample_type__fprintf(fp, &first, evsel->attr.sample_type);
1941 		if (evsel->attr.read_format)
1942 			printed += read_format__fprintf(fp, &first, evsel->attr.read_format);
1943 		if_print(disabled);
1944 		if_print(inherit);
1945 		if_print(pinned);
1946 		if_print(exclusive);
1947 		if_print(exclude_user);
1948 		if_print(exclude_kernel);
1949 		if_print(exclude_hv);
1950 		if_print(exclude_idle);
1951 		if_print(mmap);
1952 		if_print(mmap2);
1953 		if_print(comm);
1954 		if_print(comm_exec);
1955 		if_print(freq);
1956 		if_print(inherit_stat);
1957 		if_print(enable_on_exec);
1958 		if_print(task);
1959 		if_print(watermark);
1960 		if_print(precise_ip);
1961 		if_print(mmap_data);
1962 		if_print(sample_id_all);
1963 		if_print(exclude_host);
1964 		if_print(exclude_guest);
1965 		if_print(__reserved_1);
1966 		if_print(wakeup_events);
1967 		if_print(bp_type);
1968 		if_print(branch_sample_type);
1969 	}
1970 out:
1971 	fputc('\n', fp);
1972 	return ++printed;
1973 }
1974 
1975 bool perf_evsel__fallback(struct perf_evsel *evsel, int err,
1976 			  char *msg, size_t msgsize)
1977 {
1978 	if ((err == ENOENT || err == ENXIO || err == ENODEV) &&
1979 	    evsel->attr.type   == PERF_TYPE_HARDWARE &&
1980 	    evsel->attr.config == PERF_COUNT_HW_CPU_CYCLES) {
1981 		/*
1982 		 * If it's cycles then fall back to hrtimer based
1983 		 * cpu-clock-tick sw counter, which is always available even if
1984 		 * no PMU support.
1985 		 *
1986 		 * PPC returns ENXIO until 2.6.37 (behavior changed with commit
1987 		 * b0a873e).
1988 		 */
1989 		scnprintf(msg, msgsize, "%s",
1990 "The cycles event is not supported, trying to fall back to cpu-clock-ticks");
1991 
1992 		evsel->attr.type   = PERF_TYPE_SOFTWARE;
1993 		evsel->attr.config = PERF_COUNT_SW_CPU_CLOCK;
1994 
1995 		zfree(&evsel->name);
1996 		return true;
1997 	}
1998 
1999 	return false;
2000 }
2001 
2002 int perf_evsel__open_strerror(struct perf_evsel *evsel, struct target *target,
2003 			      int err, char *msg, size_t size)
2004 {
2005 	switch (err) {
2006 	case EPERM:
2007 	case EACCES:
2008 		return scnprintf(msg, size,
2009 		 "You may not have permission to collect %sstats.\n"
2010 		 "Consider tweaking /proc/sys/kernel/perf_event_paranoid:\n"
2011 		 " -1 - Not paranoid at all\n"
2012 		 "  0 - Disallow raw tracepoint access for unpriv\n"
2013 		 "  1 - Disallow cpu events for unpriv\n"
2014 		 "  2 - Disallow kernel profiling for unpriv",
2015 				 target->system_wide ? "system-wide " : "");
2016 	case ENOENT:
2017 		return scnprintf(msg, size, "The %s event is not supported.",
2018 				 perf_evsel__name(evsel));
2019 	case EMFILE:
2020 		return scnprintf(msg, size, "%s",
2021 			 "Too many events are opened.\n"
2022 			 "Try again after reducing the number of events.");
2023 	case ENODEV:
2024 		if (target->cpu_list)
2025 			return scnprintf(msg, size, "%s",
2026 	 "No such device - did you specify an out-of-range profile CPU?\n");
2027 		break;
2028 	case EOPNOTSUPP:
2029 		if (evsel->attr.precise_ip)
2030 			return scnprintf(msg, size, "%s",
2031 	"\'precise\' request may not be supported. Try removing 'p' modifier.");
2032 #if defined(__i386__) || defined(__x86_64__)
2033 		if (evsel->attr.type == PERF_TYPE_HARDWARE)
2034 			return scnprintf(msg, size, "%s",
2035 	"No hardware sampling interrupt available.\n"
2036 	"No APIC? If so then you can boot the kernel with the \"lapic\" boot parameter to force-enable it.");
2037 #endif
2038 		break;
2039 	default:
2040 		break;
2041 	}
2042 
2043 	return scnprintf(msg, size,
2044 	"The sys_perf_event_open() syscall returned with %d (%s) for event (%s).  \n"
2045 	"/bin/dmesg may provide additional information.\n"
2046 	"No CONFIG_PERF_EVENTS=y kernel support configured?\n",
2047 			 err, strerror(err), perf_evsel__name(evsel));
2048 }
2049