xref: /openbmc/linux/tools/perf/util/evsel.c (revision 6189f1b0)
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 "callchain.h"
19 #include "cgroup.h"
20 #include "evsel.h"
21 #include "evlist.h"
22 #include "util.h"
23 #include "cpumap.h"
24 #include "thread_map.h"
25 #include "target.h"
26 #include "perf_regs.h"
27 #include "debug.h"
28 #include "trace-event.h"
29 #include "stat.h"
30 
31 static struct {
32 	bool sample_id_all;
33 	bool exclude_guest;
34 	bool mmap2;
35 	bool cloexec;
36 	bool clockid;
37 	bool clockid_wrong;
38 } perf_missing_features;
39 
40 static clockid_t clockid;
41 
42 static int perf_evsel__no_extra_init(struct perf_evsel *evsel __maybe_unused)
43 {
44 	return 0;
45 }
46 
47 static void perf_evsel__no_extra_fini(struct perf_evsel *evsel __maybe_unused)
48 {
49 }
50 
51 static struct {
52 	size_t	size;
53 	int	(*init)(struct perf_evsel *evsel);
54 	void	(*fini)(struct perf_evsel *evsel);
55 } perf_evsel__object = {
56 	.size = sizeof(struct perf_evsel),
57 	.init = perf_evsel__no_extra_init,
58 	.fini = perf_evsel__no_extra_fini,
59 };
60 
61 int perf_evsel__object_config(size_t object_size,
62 			      int (*init)(struct perf_evsel *evsel),
63 			      void (*fini)(struct perf_evsel *evsel))
64 {
65 
66 	if (object_size == 0)
67 		goto set_methods;
68 
69 	if (perf_evsel__object.size > object_size)
70 		return -EINVAL;
71 
72 	perf_evsel__object.size = object_size;
73 
74 set_methods:
75 	if (init != NULL)
76 		perf_evsel__object.init = init;
77 
78 	if (fini != NULL)
79 		perf_evsel__object.fini = fini;
80 
81 	return 0;
82 }
83 
84 #define FD(e, x, y) (*(int *)xyarray__entry(e->fd, x, y))
85 
86 int __perf_evsel__sample_size(u64 sample_type)
87 {
88 	u64 mask = sample_type & PERF_SAMPLE_MASK;
89 	int size = 0;
90 	int i;
91 
92 	for (i = 0; i < 64; i++) {
93 		if (mask & (1ULL << i))
94 			size++;
95 	}
96 
97 	size *= sizeof(u64);
98 
99 	return size;
100 }
101 
102 /**
103  * __perf_evsel__calc_id_pos - calculate id_pos.
104  * @sample_type: sample type
105  *
106  * This function returns the position of the event id (PERF_SAMPLE_ID or
107  * PERF_SAMPLE_IDENTIFIER) in a sample event i.e. in the array of struct
108  * sample_event.
109  */
110 static int __perf_evsel__calc_id_pos(u64 sample_type)
111 {
112 	int idx = 0;
113 
114 	if (sample_type & PERF_SAMPLE_IDENTIFIER)
115 		return 0;
116 
117 	if (!(sample_type & PERF_SAMPLE_ID))
118 		return -1;
119 
120 	if (sample_type & PERF_SAMPLE_IP)
121 		idx += 1;
122 
123 	if (sample_type & PERF_SAMPLE_TID)
124 		idx += 1;
125 
126 	if (sample_type & PERF_SAMPLE_TIME)
127 		idx += 1;
128 
129 	if (sample_type & PERF_SAMPLE_ADDR)
130 		idx += 1;
131 
132 	return idx;
133 }
134 
135 /**
136  * __perf_evsel__calc_is_pos - calculate is_pos.
137  * @sample_type: sample type
138  *
139  * This function returns the position (counting backwards) of the event id
140  * (PERF_SAMPLE_ID or PERF_SAMPLE_IDENTIFIER) in a non-sample event i.e. if
141  * sample_id_all is used there is an id sample appended to non-sample events.
142  */
143 static int __perf_evsel__calc_is_pos(u64 sample_type)
144 {
145 	int idx = 1;
146 
147 	if (sample_type & PERF_SAMPLE_IDENTIFIER)
148 		return 1;
149 
150 	if (!(sample_type & PERF_SAMPLE_ID))
151 		return -1;
152 
153 	if (sample_type & PERF_SAMPLE_CPU)
154 		idx += 1;
155 
156 	if (sample_type & PERF_SAMPLE_STREAM_ID)
157 		idx += 1;
158 
159 	return idx;
160 }
161 
162 void perf_evsel__calc_id_pos(struct perf_evsel *evsel)
163 {
164 	evsel->id_pos = __perf_evsel__calc_id_pos(evsel->attr.sample_type);
165 	evsel->is_pos = __perf_evsel__calc_is_pos(evsel->attr.sample_type);
166 }
167 
168 void __perf_evsel__set_sample_bit(struct perf_evsel *evsel,
169 				  enum perf_event_sample_format bit)
170 {
171 	if (!(evsel->attr.sample_type & bit)) {
172 		evsel->attr.sample_type |= bit;
173 		evsel->sample_size += sizeof(u64);
174 		perf_evsel__calc_id_pos(evsel);
175 	}
176 }
177 
178 void __perf_evsel__reset_sample_bit(struct perf_evsel *evsel,
179 				    enum perf_event_sample_format bit)
180 {
181 	if (evsel->attr.sample_type & bit) {
182 		evsel->attr.sample_type &= ~bit;
183 		evsel->sample_size -= sizeof(u64);
184 		perf_evsel__calc_id_pos(evsel);
185 	}
186 }
187 
188 void perf_evsel__set_sample_id(struct perf_evsel *evsel,
189 			       bool can_sample_identifier)
190 {
191 	if (can_sample_identifier) {
192 		perf_evsel__reset_sample_bit(evsel, ID);
193 		perf_evsel__set_sample_bit(evsel, IDENTIFIER);
194 	} else {
195 		perf_evsel__set_sample_bit(evsel, ID);
196 	}
197 	evsel->attr.read_format |= PERF_FORMAT_ID;
198 }
199 
200 void perf_evsel__init(struct perf_evsel *evsel,
201 		      struct perf_event_attr *attr, int idx)
202 {
203 	evsel->idx	   = idx;
204 	evsel->tracking	   = !idx;
205 	evsel->attr	   = *attr;
206 	evsel->leader	   = evsel;
207 	evsel->unit	   = "";
208 	evsel->scale	   = 1.0;
209 	INIT_LIST_HEAD(&evsel->node);
210 	perf_evsel__object.init(evsel);
211 	evsel->sample_size = __perf_evsel__sample_size(attr->sample_type);
212 	perf_evsel__calc_id_pos(evsel);
213 }
214 
215 struct perf_evsel *perf_evsel__new_idx(struct perf_event_attr *attr, int idx)
216 {
217 	struct perf_evsel *evsel = zalloc(perf_evsel__object.size);
218 
219 	if (evsel != NULL)
220 		perf_evsel__init(evsel, attr, idx);
221 
222 	return evsel;
223 }
224 
225 struct perf_evsel *perf_evsel__newtp_idx(const char *sys, const char *name, int idx)
226 {
227 	struct perf_evsel *evsel = zalloc(perf_evsel__object.size);
228 
229 	if (evsel != NULL) {
230 		struct perf_event_attr attr = {
231 			.type	       = PERF_TYPE_TRACEPOINT,
232 			.sample_type   = (PERF_SAMPLE_RAW | PERF_SAMPLE_TIME |
233 					  PERF_SAMPLE_CPU | PERF_SAMPLE_PERIOD),
234 		};
235 
236 		if (asprintf(&evsel->name, "%s:%s", sys, name) < 0)
237 			goto out_free;
238 
239 		evsel->tp_format = trace_event__tp_format(sys, name);
240 		if (evsel->tp_format == NULL)
241 			goto out_free;
242 
243 		event_attr_init(&attr);
244 		attr.config = evsel->tp_format->id;
245 		attr.sample_period = 1;
246 		perf_evsel__init(evsel, &attr, idx);
247 	}
248 
249 	return evsel;
250 
251 out_free:
252 	zfree(&evsel->name);
253 	free(evsel);
254 	return NULL;
255 }
256 
257 const char *perf_evsel__hw_names[PERF_COUNT_HW_MAX] = {
258 	"cycles",
259 	"instructions",
260 	"cache-references",
261 	"cache-misses",
262 	"branches",
263 	"branch-misses",
264 	"bus-cycles",
265 	"stalled-cycles-frontend",
266 	"stalled-cycles-backend",
267 	"ref-cycles",
268 };
269 
270 static const char *__perf_evsel__hw_name(u64 config)
271 {
272 	if (config < PERF_COUNT_HW_MAX && perf_evsel__hw_names[config])
273 		return perf_evsel__hw_names[config];
274 
275 	return "unknown-hardware";
276 }
277 
278 static int perf_evsel__add_modifiers(struct perf_evsel *evsel, char *bf, size_t size)
279 {
280 	int colon = 0, r = 0;
281 	struct perf_event_attr *attr = &evsel->attr;
282 	bool exclude_guest_default = false;
283 
284 #define MOD_PRINT(context, mod)	do {					\
285 		if (!attr->exclude_##context) {				\
286 			if (!colon) colon = ++r;			\
287 			r += scnprintf(bf + r, size - r, "%c", mod);	\
288 		} } while(0)
289 
290 	if (attr->exclude_kernel || attr->exclude_user || attr->exclude_hv) {
291 		MOD_PRINT(kernel, 'k');
292 		MOD_PRINT(user, 'u');
293 		MOD_PRINT(hv, 'h');
294 		exclude_guest_default = true;
295 	}
296 
297 	if (attr->precise_ip) {
298 		if (!colon)
299 			colon = ++r;
300 		r += scnprintf(bf + r, size - r, "%.*s", attr->precise_ip, "ppp");
301 		exclude_guest_default = true;
302 	}
303 
304 	if (attr->exclude_host || attr->exclude_guest == exclude_guest_default) {
305 		MOD_PRINT(host, 'H');
306 		MOD_PRINT(guest, 'G');
307 	}
308 #undef MOD_PRINT
309 	if (colon)
310 		bf[colon - 1] = ':';
311 	return r;
312 }
313 
314 static int perf_evsel__hw_name(struct perf_evsel *evsel, char *bf, size_t size)
315 {
316 	int r = scnprintf(bf, size, "%s", __perf_evsel__hw_name(evsel->attr.config));
317 	return r + perf_evsel__add_modifiers(evsel, bf + r, size - r);
318 }
319 
320 const char *perf_evsel__sw_names[PERF_COUNT_SW_MAX] = {
321 	"cpu-clock",
322 	"task-clock",
323 	"page-faults",
324 	"context-switches",
325 	"cpu-migrations",
326 	"minor-faults",
327 	"major-faults",
328 	"alignment-faults",
329 	"emulation-faults",
330 	"dummy",
331 };
332 
333 static const char *__perf_evsel__sw_name(u64 config)
334 {
335 	if (config < PERF_COUNT_SW_MAX && perf_evsel__sw_names[config])
336 		return perf_evsel__sw_names[config];
337 	return "unknown-software";
338 }
339 
340 static int perf_evsel__sw_name(struct perf_evsel *evsel, char *bf, size_t size)
341 {
342 	int r = scnprintf(bf, size, "%s", __perf_evsel__sw_name(evsel->attr.config));
343 	return r + perf_evsel__add_modifiers(evsel, bf + r, size - r);
344 }
345 
346 static int __perf_evsel__bp_name(char *bf, size_t size, u64 addr, u64 type)
347 {
348 	int r;
349 
350 	r = scnprintf(bf, size, "mem:0x%" PRIx64 ":", addr);
351 
352 	if (type & HW_BREAKPOINT_R)
353 		r += scnprintf(bf + r, size - r, "r");
354 
355 	if (type & HW_BREAKPOINT_W)
356 		r += scnprintf(bf + r, size - r, "w");
357 
358 	if (type & HW_BREAKPOINT_X)
359 		r += scnprintf(bf + r, size - r, "x");
360 
361 	return r;
362 }
363 
364 static int perf_evsel__bp_name(struct perf_evsel *evsel, char *bf, size_t size)
365 {
366 	struct perf_event_attr *attr = &evsel->attr;
367 	int r = __perf_evsel__bp_name(bf, size, attr->bp_addr, attr->bp_type);
368 	return r + perf_evsel__add_modifiers(evsel, bf + r, size - r);
369 }
370 
371 const char *perf_evsel__hw_cache[PERF_COUNT_HW_CACHE_MAX]
372 				[PERF_EVSEL__MAX_ALIASES] = {
373  { "L1-dcache",	"l1-d",		"l1d",		"L1-data",		},
374  { "L1-icache",	"l1-i",		"l1i",		"L1-instruction",	},
375  { "LLC",	"L2",							},
376  { "dTLB",	"d-tlb",	"Data-TLB",				},
377  { "iTLB",	"i-tlb",	"Instruction-TLB",			},
378  { "branch",	"branches",	"bpu",		"btb",		"bpc",	},
379  { "node",								},
380 };
381 
382 const char *perf_evsel__hw_cache_op[PERF_COUNT_HW_CACHE_OP_MAX]
383 				   [PERF_EVSEL__MAX_ALIASES] = {
384  { "load",	"loads",	"read",					},
385  { "store",	"stores",	"write",				},
386  { "prefetch",	"prefetches",	"speculative-read", "speculative-load",	},
387 };
388 
389 const char *perf_evsel__hw_cache_result[PERF_COUNT_HW_CACHE_RESULT_MAX]
390 				       [PERF_EVSEL__MAX_ALIASES] = {
391  { "refs",	"Reference",	"ops",		"access",		},
392  { "misses",	"miss",							},
393 };
394 
395 #define C(x)		PERF_COUNT_HW_CACHE_##x
396 #define CACHE_READ	(1 << C(OP_READ))
397 #define CACHE_WRITE	(1 << C(OP_WRITE))
398 #define CACHE_PREFETCH	(1 << C(OP_PREFETCH))
399 #define COP(x)		(1 << x)
400 
401 /*
402  * cache operartion stat
403  * L1I : Read and prefetch only
404  * ITLB and BPU : Read-only
405  */
406 static unsigned long perf_evsel__hw_cache_stat[C(MAX)] = {
407  [C(L1D)]	= (CACHE_READ | CACHE_WRITE | CACHE_PREFETCH),
408  [C(L1I)]	= (CACHE_READ | CACHE_PREFETCH),
409  [C(LL)]	= (CACHE_READ | CACHE_WRITE | CACHE_PREFETCH),
410  [C(DTLB)]	= (CACHE_READ | CACHE_WRITE | CACHE_PREFETCH),
411  [C(ITLB)]	= (CACHE_READ),
412  [C(BPU)]	= (CACHE_READ),
413  [C(NODE)]	= (CACHE_READ | CACHE_WRITE | CACHE_PREFETCH),
414 };
415 
416 bool perf_evsel__is_cache_op_valid(u8 type, u8 op)
417 {
418 	if (perf_evsel__hw_cache_stat[type] & COP(op))
419 		return true;	/* valid */
420 	else
421 		return false;	/* invalid */
422 }
423 
424 int __perf_evsel__hw_cache_type_op_res_name(u8 type, u8 op, u8 result,
425 					    char *bf, size_t size)
426 {
427 	if (result) {
428 		return scnprintf(bf, size, "%s-%s-%s", perf_evsel__hw_cache[type][0],
429 				 perf_evsel__hw_cache_op[op][0],
430 				 perf_evsel__hw_cache_result[result][0]);
431 	}
432 
433 	return scnprintf(bf, size, "%s-%s", perf_evsel__hw_cache[type][0],
434 			 perf_evsel__hw_cache_op[op][1]);
435 }
436 
437 static int __perf_evsel__hw_cache_name(u64 config, char *bf, size_t size)
438 {
439 	u8 op, result, type = (config >>  0) & 0xff;
440 	const char *err = "unknown-ext-hardware-cache-type";
441 
442 	if (type > PERF_COUNT_HW_CACHE_MAX)
443 		goto out_err;
444 
445 	op = (config >>  8) & 0xff;
446 	err = "unknown-ext-hardware-cache-op";
447 	if (op > PERF_COUNT_HW_CACHE_OP_MAX)
448 		goto out_err;
449 
450 	result = (config >> 16) & 0xff;
451 	err = "unknown-ext-hardware-cache-result";
452 	if (result > PERF_COUNT_HW_CACHE_RESULT_MAX)
453 		goto out_err;
454 
455 	err = "invalid-cache";
456 	if (!perf_evsel__is_cache_op_valid(type, op))
457 		goto out_err;
458 
459 	return __perf_evsel__hw_cache_type_op_res_name(type, op, result, bf, size);
460 out_err:
461 	return scnprintf(bf, size, "%s", err);
462 }
463 
464 static int perf_evsel__hw_cache_name(struct perf_evsel *evsel, char *bf, size_t size)
465 {
466 	int ret = __perf_evsel__hw_cache_name(evsel->attr.config, bf, size);
467 	return ret + perf_evsel__add_modifiers(evsel, bf + ret, size - ret);
468 }
469 
470 static int perf_evsel__raw_name(struct perf_evsel *evsel, char *bf, size_t size)
471 {
472 	int ret = scnprintf(bf, size, "raw 0x%" PRIx64, evsel->attr.config);
473 	return ret + perf_evsel__add_modifiers(evsel, bf + ret, size - ret);
474 }
475 
476 const char *perf_evsel__name(struct perf_evsel *evsel)
477 {
478 	char bf[128];
479 
480 	if (evsel->name)
481 		return evsel->name;
482 
483 	switch (evsel->attr.type) {
484 	case PERF_TYPE_RAW:
485 		perf_evsel__raw_name(evsel, bf, sizeof(bf));
486 		break;
487 
488 	case PERF_TYPE_HARDWARE:
489 		perf_evsel__hw_name(evsel, bf, sizeof(bf));
490 		break;
491 
492 	case PERF_TYPE_HW_CACHE:
493 		perf_evsel__hw_cache_name(evsel, bf, sizeof(bf));
494 		break;
495 
496 	case PERF_TYPE_SOFTWARE:
497 		perf_evsel__sw_name(evsel, bf, sizeof(bf));
498 		break;
499 
500 	case PERF_TYPE_TRACEPOINT:
501 		scnprintf(bf, sizeof(bf), "%s", "unknown tracepoint");
502 		break;
503 
504 	case PERF_TYPE_BREAKPOINT:
505 		perf_evsel__bp_name(evsel, bf, sizeof(bf));
506 		break;
507 
508 	default:
509 		scnprintf(bf, sizeof(bf), "unknown attr type: %d",
510 			  evsel->attr.type);
511 		break;
512 	}
513 
514 	evsel->name = strdup(bf);
515 
516 	return evsel->name ?: "unknown";
517 }
518 
519 const char *perf_evsel__group_name(struct perf_evsel *evsel)
520 {
521 	return evsel->group_name ?: "anon group";
522 }
523 
524 int perf_evsel__group_desc(struct perf_evsel *evsel, char *buf, size_t size)
525 {
526 	int ret;
527 	struct perf_evsel *pos;
528 	const char *group_name = perf_evsel__group_name(evsel);
529 
530 	ret = scnprintf(buf, size, "%s", group_name);
531 
532 	ret += scnprintf(buf + ret, size - ret, " { %s",
533 			 perf_evsel__name(evsel));
534 
535 	for_each_group_member(pos, evsel)
536 		ret += scnprintf(buf + ret, size - ret, ", %s",
537 				 perf_evsel__name(pos));
538 
539 	ret += scnprintf(buf + ret, size - ret, " }");
540 
541 	return ret;
542 }
543 
544 static void
545 perf_evsel__config_callgraph(struct perf_evsel *evsel,
546 			     struct record_opts *opts)
547 {
548 	bool function = perf_evsel__is_function_event(evsel);
549 	struct perf_event_attr *attr = &evsel->attr;
550 
551 	perf_evsel__set_sample_bit(evsel, CALLCHAIN);
552 
553 	if (callchain_param.record_mode == CALLCHAIN_LBR) {
554 		if (!opts->branch_stack) {
555 			if (attr->exclude_user) {
556 				pr_warning("LBR callstack option is only available "
557 					   "to get user callchain information. "
558 					   "Falling back to framepointers.\n");
559 			} else {
560 				perf_evsel__set_sample_bit(evsel, BRANCH_STACK);
561 				attr->branch_sample_type = PERF_SAMPLE_BRANCH_USER |
562 							PERF_SAMPLE_BRANCH_CALL_STACK;
563 			}
564 		} else
565 			 pr_warning("Cannot use LBR callstack with branch stack. "
566 				    "Falling back to framepointers.\n");
567 	}
568 
569 	if (callchain_param.record_mode == CALLCHAIN_DWARF) {
570 		if (!function) {
571 			perf_evsel__set_sample_bit(evsel, REGS_USER);
572 			perf_evsel__set_sample_bit(evsel, STACK_USER);
573 			attr->sample_regs_user = PERF_REGS_MASK;
574 			attr->sample_stack_user = callchain_param.dump_size;
575 			attr->exclude_callchain_user = 1;
576 		} else {
577 			pr_info("Cannot use DWARF unwind for function trace event,"
578 				" falling back to framepointers.\n");
579 		}
580 	}
581 
582 	if (function) {
583 		pr_info("Disabling user space callchains for function trace event.\n");
584 		attr->exclude_callchain_user = 1;
585 	}
586 }
587 
588 /*
589  * The enable_on_exec/disabled value strategy:
590  *
591  *  1) For any type of traced program:
592  *    - all independent events and group leaders are disabled
593  *    - all group members are enabled
594  *
595  *     Group members are ruled by group leaders. They need to
596  *     be enabled, because the group scheduling relies on that.
597  *
598  *  2) For traced programs executed by perf:
599  *     - all independent events and group leaders have
600  *       enable_on_exec set
601  *     - we don't specifically enable or disable any event during
602  *       the record command
603  *
604  *     Independent events and group leaders are initially disabled
605  *     and get enabled by exec. Group members are ruled by group
606  *     leaders as stated in 1).
607  *
608  *  3) For traced programs attached by perf (pid/tid):
609  *     - we specifically enable or disable all events during
610  *       the record command
611  *
612  *     When attaching events to already running traced we
613  *     enable/disable events specifically, as there's no
614  *     initial traced exec call.
615  */
616 void perf_evsel__config(struct perf_evsel *evsel, struct record_opts *opts)
617 {
618 	struct perf_evsel *leader = evsel->leader;
619 	struct perf_event_attr *attr = &evsel->attr;
620 	int track = evsel->tracking;
621 	bool per_cpu = opts->target.default_per_cpu && !opts->target.per_thread;
622 
623 	attr->sample_id_all = perf_missing_features.sample_id_all ? 0 : 1;
624 	attr->inherit	    = !opts->no_inherit;
625 
626 	perf_evsel__set_sample_bit(evsel, IP);
627 	perf_evsel__set_sample_bit(evsel, TID);
628 
629 	if (evsel->sample_read) {
630 		perf_evsel__set_sample_bit(evsel, READ);
631 
632 		/*
633 		 * We need ID even in case of single event, because
634 		 * PERF_SAMPLE_READ process ID specific data.
635 		 */
636 		perf_evsel__set_sample_id(evsel, false);
637 
638 		/*
639 		 * Apply group format only if we belong to group
640 		 * with more than one members.
641 		 */
642 		if (leader->nr_members > 1) {
643 			attr->read_format |= PERF_FORMAT_GROUP;
644 			attr->inherit = 0;
645 		}
646 	}
647 
648 	/*
649 	 * We default some events to have a default interval. But keep
650 	 * it a weak assumption overridable by the user.
651 	 */
652 	if (!attr->sample_period || (opts->user_freq != UINT_MAX ||
653 				     opts->user_interval != ULLONG_MAX)) {
654 		if (opts->freq) {
655 			perf_evsel__set_sample_bit(evsel, PERIOD);
656 			attr->freq		= 1;
657 			attr->sample_freq	= opts->freq;
658 		} else {
659 			attr->sample_period = opts->default_interval;
660 		}
661 	}
662 
663 	/*
664 	 * Disable sampling for all group members other
665 	 * than leader in case leader 'leads' the sampling.
666 	 */
667 	if ((leader != evsel) && leader->sample_read) {
668 		attr->sample_freq   = 0;
669 		attr->sample_period = 0;
670 	}
671 
672 	if (opts->no_samples)
673 		attr->sample_freq = 0;
674 
675 	if (opts->inherit_stat)
676 		attr->inherit_stat = 1;
677 
678 	if (opts->sample_address) {
679 		perf_evsel__set_sample_bit(evsel, ADDR);
680 		attr->mmap_data = track;
681 	}
682 
683 	/*
684 	 * We don't allow user space callchains for  function trace
685 	 * event, due to issues with page faults while tracing page
686 	 * fault handler and its overall trickiness nature.
687 	 */
688 	if (perf_evsel__is_function_event(evsel))
689 		evsel->attr.exclude_callchain_user = 1;
690 
691 	if (callchain_param.enabled && !evsel->no_aux_samples)
692 		perf_evsel__config_callgraph(evsel, opts);
693 
694 	if (opts->sample_intr_regs) {
695 		attr->sample_regs_intr = PERF_REGS_MASK;
696 		perf_evsel__set_sample_bit(evsel, REGS_INTR);
697 	}
698 
699 	if (target__has_cpu(&opts->target))
700 		perf_evsel__set_sample_bit(evsel, CPU);
701 
702 	if (opts->period)
703 		perf_evsel__set_sample_bit(evsel, PERIOD);
704 
705 	/*
706 	 * When the user explicitely disabled time don't force it here.
707 	 */
708 	if (opts->sample_time &&
709 	    (!perf_missing_features.sample_id_all &&
710 	    (!opts->no_inherit || target__has_cpu(&opts->target) || per_cpu)))
711 		perf_evsel__set_sample_bit(evsel, TIME);
712 
713 	if (opts->raw_samples && !evsel->no_aux_samples) {
714 		perf_evsel__set_sample_bit(evsel, TIME);
715 		perf_evsel__set_sample_bit(evsel, RAW);
716 		perf_evsel__set_sample_bit(evsel, CPU);
717 	}
718 
719 	if (opts->sample_address)
720 		perf_evsel__set_sample_bit(evsel, DATA_SRC);
721 
722 	if (opts->no_buffering) {
723 		attr->watermark = 0;
724 		attr->wakeup_events = 1;
725 	}
726 	if (opts->branch_stack && !evsel->no_aux_samples) {
727 		perf_evsel__set_sample_bit(evsel, BRANCH_STACK);
728 		attr->branch_sample_type = opts->branch_stack;
729 	}
730 
731 	if (opts->sample_weight)
732 		perf_evsel__set_sample_bit(evsel, WEIGHT);
733 
734 	attr->task  = track;
735 	attr->mmap  = track;
736 	attr->mmap2 = track && !perf_missing_features.mmap2;
737 	attr->comm  = track;
738 
739 	if (opts->sample_transaction)
740 		perf_evsel__set_sample_bit(evsel, TRANSACTION);
741 
742 	if (opts->running_time) {
743 		evsel->attr.read_format |=
744 			PERF_FORMAT_TOTAL_TIME_ENABLED |
745 			PERF_FORMAT_TOTAL_TIME_RUNNING;
746 	}
747 
748 	/*
749 	 * XXX see the function comment above
750 	 *
751 	 * Disabling only independent events or group leaders,
752 	 * keeping group members enabled.
753 	 */
754 	if (perf_evsel__is_group_leader(evsel))
755 		attr->disabled = 1;
756 
757 	/*
758 	 * Setting enable_on_exec for independent events and
759 	 * group leaders for traced executed by perf.
760 	 */
761 	if (target__none(&opts->target) && perf_evsel__is_group_leader(evsel) &&
762 		!opts->initial_delay)
763 		attr->enable_on_exec = 1;
764 
765 	if (evsel->immediate) {
766 		attr->disabled = 0;
767 		attr->enable_on_exec = 0;
768 	}
769 
770 	clockid = opts->clockid;
771 	if (opts->use_clockid) {
772 		attr->use_clockid = 1;
773 		attr->clockid = opts->clockid;
774 	}
775 }
776 
777 static int perf_evsel__alloc_fd(struct perf_evsel *evsel, int ncpus, int nthreads)
778 {
779 	int cpu, thread;
780 
781 	if (evsel->system_wide)
782 		nthreads = 1;
783 
784 	evsel->fd = xyarray__new(ncpus, nthreads, sizeof(int));
785 
786 	if (evsel->fd) {
787 		for (cpu = 0; cpu < ncpus; cpu++) {
788 			for (thread = 0; thread < nthreads; thread++) {
789 				FD(evsel, cpu, thread) = -1;
790 			}
791 		}
792 	}
793 
794 	return evsel->fd != NULL ? 0 : -ENOMEM;
795 }
796 
797 static int perf_evsel__run_ioctl(struct perf_evsel *evsel, int ncpus, int nthreads,
798 			  int ioc,  void *arg)
799 {
800 	int cpu, thread;
801 
802 	if (evsel->system_wide)
803 		nthreads = 1;
804 
805 	for (cpu = 0; cpu < ncpus; cpu++) {
806 		for (thread = 0; thread < nthreads; thread++) {
807 			int fd = FD(evsel, cpu, thread),
808 			    err = ioctl(fd, ioc, arg);
809 
810 			if (err)
811 				return err;
812 		}
813 	}
814 
815 	return 0;
816 }
817 
818 int perf_evsel__set_filter(struct perf_evsel *evsel, int ncpus, int nthreads,
819 			   const char *filter)
820 {
821 	return perf_evsel__run_ioctl(evsel, ncpus, nthreads,
822 				     PERF_EVENT_IOC_SET_FILTER,
823 				     (void *)filter);
824 }
825 
826 int perf_evsel__enable(struct perf_evsel *evsel, int ncpus, int nthreads)
827 {
828 	return perf_evsel__run_ioctl(evsel, ncpus, nthreads,
829 				     PERF_EVENT_IOC_ENABLE,
830 				     0);
831 }
832 
833 int perf_evsel__alloc_id(struct perf_evsel *evsel, int ncpus, int nthreads)
834 {
835 	if (ncpus == 0 || nthreads == 0)
836 		return 0;
837 
838 	if (evsel->system_wide)
839 		nthreads = 1;
840 
841 	evsel->sample_id = xyarray__new(ncpus, nthreads, sizeof(struct perf_sample_id));
842 	if (evsel->sample_id == NULL)
843 		return -ENOMEM;
844 
845 	evsel->id = zalloc(ncpus * nthreads * sizeof(u64));
846 	if (evsel->id == NULL) {
847 		xyarray__delete(evsel->sample_id);
848 		evsel->sample_id = NULL;
849 		return -ENOMEM;
850 	}
851 
852 	return 0;
853 }
854 
855 static void perf_evsel__free_fd(struct perf_evsel *evsel)
856 {
857 	xyarray__delete(evsel->fd);
858 	evsel->fd = NULL;
859 }
860 
861 static void perf_evsel__free_id(struct perf_evsel *evsel)
862 {
863 	xyarray__delete(evsel->sample_id);
864 	evsel->sample_id = NULL;
865 	zfree(&evsel->id);
866 }
867 
868 void perf_evsel__close_fd(struct perf_evsel *evsel, int ncpus, int nthreads)
869 {
870 	int cpu, thread;
871 
872 	if (evsel->system_wide)
873 		nthreads = 1;
874 
875 	for (cpu = 0; cpu < ncpus; cpu++)
876 		for (thread = 0; thread < nthreads; ++thread) {
877 			close(FD(evsel, cpu, thread));
878 			FD(evsel, cpu, thread) = -1;
879 		}
880 }
881 
882 void perf_evsel__exit(struct perf_evsel *evsel)
883 {
884 	assert(list_empty(&evsel->node));
885 	perf_evsel__free_fd(evsel);
886 	perf_evsel__free_id(evsel);
887 	close_cgroup(evsel->cgrp);
888 	cpu_map__put(evsel->cpus);
889 	thread_map__put(evsel->threads);
890 	zfree(&evsel->group_name);
891 	zfree(&evsel->name);
892 	perf_evsel__object.fini(evsel);
893 }
894 
895 void perf_evsel__delete(struct perf_evsel *evsel)
896 {
897 	perf_evsel__exit(evsel);
898 	free(evsel);
899 }
900 
901 void perf_evsel__compute_deltas(struct perf_evsel *evsel, int cpu, int thread,
902 				struct perf_counts_values *count)
903 {
904 	struct perf_counts_values tmp;
905 
906 	if (!evsel->prev_raw_counts)
907 		return;
908 
909 	if (cpu == -1) {
910 		tmp = evsel->prev_raw_counts->aggr;
911 		evsel->prev_raw_counts->aggr = *count;
912 	} else {
913 		tmp = *perf_counts(evsel->prev_raw_counts, cpu, thread);
914 		*perf_counts(evsel->prev_raw_counts, cpu, thread) = *count;
915 	}
916 
917 	count->val = count->val - tmp.val;
918 	count->ena = count->ena - tmp.ena;
919 	count->run = count->run - tmp.run;
920 }
921 
922 void perf_counts_values__scale(struct perf_counts_values *count,
923 			       bool scale, s8 *pscaled)
924 {
925 	s8 scaled = 0;
926 
927 	if (scale) {
928 		if (count->run == 0) {
929 			scaled = -1;
930 			count->val = 0;
931 		} else if (count->run < count->ena) {
932 			scaled = 1;
933 			count->val = (u64)((double) count->val * count->ena / count->run + 0.5);
934 		}
935 	} else
936 		count->ena = count->run = 0;
937 
938 	if (pscaled)
939 		*pscaled = scaled;
940 }
941 
942 int perf_evsel__read(struct perf_evsel *evsel, int cpu, int thread,
943 		     struct perf_counts_values *count)
944 {
945 	memset(count, 0, sizeof(*count));
946 
947 	if (FD(evsel, cpu, thread) < 0)
948 		return -EINVAL;
949 
950 	if (readn(FD(evsel, cpu, thread), count, sizeof(*count)) < 0)
951 		return -errno;
952 
953 	return 0;
954 }
955 
956 int __perf_evsel__read_on_cpu(struct perf_evsel *evsel,
957 			      int cpu, int thread, bool scale)
958 {
959 	struct perf_counts_values count;
960 	size_t nv = scale ? 3 : 1;
961 
962 	if (FD(evsel, cpu, thread) < 0)
963 		return -EINVAL;
964 
965 	if (evsel->counts == NULL && perf_evsel__alloc_counts(evsel, cpu + 1, thread + 1) < 0)
966 		return -ENOMEM;
967 
968 	if (readn(FD(evsel, cpu, thread), &count, nv * sizeof(u64)) < 0)
969 		return -errno;
970 
971 	perf_evsel__compute_deltas(evsel, cpu, thread, &count);
972 	perf_counts_values__scale(&count, scale, NULL);
973 	*perf_counts(evsel->counts, cpu, thread) = count;
974 	return 0;
975 }
976 
977 static int get_group_fd(struct perf_evsel *evsel, int cpu, int thread)
978 {
979 	struct perf_evsel *leader = evsel->leader;
980 	int fd;
981 
982 	if (perf_evsel__is_group_leader(evsel))
983 		return -1;
984 
985 	/*
986 	 * Leader must be already processed/open,
987 	 * if not it's a bug.
988 	 */
989 	BUG_ON(!leader->fd);
990 
991 	fd = FD(leader, cpu, thread);
992 	BUG_ON(fd == -1);
993 
994 	return fd;
995 }
996 
997 struct bit_names {
998 	int bit;
999 	const char *name;
1000 };
1001 
1002 static void __p_bits(char *buf, size_t size, u64 value, struct bit_names *bits)
1003 {
1004 	bool first_bit = true;
1005 	int i = 0;
1006 
1007 	do {
1008 		if (value & bits[i].bit) {
1009 			buf += scnprintf(buf, size, "%s%s", first_bit ? "" : "|", bits[i].name);
1010 			first_bit = false;
1011 		}
1012 	} while (bits[++i].name != NULL);
1013 }
1014 
1015 static void __p_sample_type(char *buf, size_t size, u64 value)
1016 {
1017 #define bit_name(n) { PERF_SAMPLE_##n, #n }
1018 	struct bit_names bits[] = {
1019 		bit_name(IP), bit_name(TID), bit_name(TIME), bit_name(ADDR),
1020 		bit_name(READ), bit_name(CALLCHAIN), bit_name(ID), bit_name(CPU),
1021 		bit_name(PERIOD), bit_name(STREAM_ID), bit_name(RAW),
1022 		bit_name(BRANCH_STACK), bit_name(REGS_USER), bit_name(STACK_USER),
1023 		bit_name(IDENTIFIER), bit_name(REGS_INTR),
1024 		{ .name = NULL, }
1025 	};
1026 #undef bit_name
1027 	__p_bits(buf, size, value, bits);
1028 }
1029 
1030 static void __p_read_format(char *buf, size_t size, u64 value)
1031 {
1032 #define bit_name(n) { PERF_FORMAT_##n, #n }
1033 	struct bit_names bits[] = {
1034 		bit_name(TOTAL_TIME_ENABLED), bit_name(TOTAL_TIME_RUNNING),
1035 		bit_name(ID), bit_name(GROUP),
1036 		{ .name = NULL, }
1037 	};
1038 #undef bit_name
1039 	__p_bits(buf, size, value, bits);
1040 }
1041 
1042 #define BUF_SIZE		1024
1043 
1044 #define p_hex(val)		snprintf(buf, BUF_SIZE, "%#"PRIx64, (uint64_t)(val))
1045 #define p_unsigned(val)		snprintf(buf, BUF_SIZE, "%"PRIu64, (uint64_t)(val))
1046 #define p_signed(val)		snprintf(buf, BUF_SIZE, "%"PRId64, (int64_t)(val))
1047 #define p_sample_type(val)	__p_sample_type(buf, BUF_SIZE, val)
1048 #define p_read_format(val)	__p_read_format(buf, BUF_SIZE, val)
1049 
1050 #define PRINT_ATTRn(_n, _f, _p)				\
1051 do {							\
1052 	if (attr->_f) {					\
1053 		_p(attr->_f);				\
1054 		ret += attr__fprintf(fp, _n, buf, priv);\
1055 	}						\
1056 } while (0)
1057 
1058 #define PRINT_ATTRf(_f, _p)	PRINT_ATTRn(#_f, _f, _p)
1059 
1060 int perf_event_attr__fprintf(FILE *fp, struct perf_event_attr *attr,
1061 			     attr__fprintf_f attr__fprintf, void *priv)
1062 {
1063 	char buf[BUF_SIZE];
1064 	int ret = 0;
1065 
1066 	PRINT_ATTRf(type, p_unsigned);
1067 	PRINT_ATTRf(size, p_unsigned);
1068 	PRINT_ATTRf(config, p_hex);
1069 	PRINT_ATTRn("{ sample_period, sample_freq }", sample_period, p_unsigned);
1070 	PRINT_ATTRf(sample_type, p_sample_type);
1071 	PRINT_ATTRf(read_format, p_read_format);
1072 
1073 	PRINT_ATTRf(disabled, p_unsigned);
1074 	PRINT_ATTRf(inherit, p_unsigned);
1075 	PRINT_ATTRf(pinned, p_unsigned);
1076 	PRINT_ATTRf(exclusive, p_unsigned);
1077 	PRINT_ATTRf(exclude_user, p_unsigned);
1078 	PRINT_ATTRf(exclude_kernel, p_unsigned);
1079 	PRINT_ATTRf(exclude_hv, p_unsigned);
1080 	PRINT_ATTRf(exclude_idle, p_unsigned);
1081 	PRINT_ATTRf(mmap, p_unsigned);
1082 	PRINT_ATTRf(comm, p_unsigned);
1083 	PRINT_ATTRf(freq, p_unsigned);
1084 	PRINT_ATTRf(inherit_stat, p_unsigned);
1085 	PRINT_ATTRf(enable_on_exec, p_unsigned);
1086 	PRINT_ATTRf(task, p_unsigned);
1087 	PRINT_ATTRf(watermark, p_unsigned);
1088 	PRINT_ATTRf(precise_ip, p_unsigned);
1089 	PRINT_ATTRf(mmap_data, p_unsigned);
1090 	PRINT_ATTRf(sample_id_all, p_unsigned);
1091 	PRINT_ATTRf(exclude_host, p_unsigned);
1092 	PRINT_ATTRf(exclude_guest, p_unsigned);
1093 	PRINT_ATTRf(exclude_callchain_kernel, p_unsigned);
1094 	PRINT_ATTRf(exclude_callchain_user, p_unsigned);
1095 	PRINT_ATTRf(mmap2, p_unsigned);
1096 	PRINT_ATTRf(comm_exec, p_unsigned);
1097 	PRINT_ATTRf(use_clockid, p_unsigned);
1098 
1099 	PRINT_ATTRn("{ wakeup_events, wakeup_watermark }", wakeup_events, p_unsigned);
1100 	PRINT_ATTRf(bp_type, p_unsigned);
1101 	PRINT_ATTRn("{ bp_addr, config1 }", bp_addr, p_hex);
1102 	PRINT_ATTRn("{ bp_len, config2 }", bp_len, p_hex);
1103 	PRINT_ATTRf(sample_regs_user, p_hex);
1104 	PRINT_ATTRf(sample_stack_user, p_unsigned);
1105 	PRINT_ATTRf(clockid, p_signed);
1106 	PRINT_ATTRf(sample_regs_intr, p_hex);
1107 	PRINT_ATTRf(aux_watermark, p_unsigned);
1108 
1109 	return ret;
1110 }
1111 
1112 static int __open_attr__fprintf(FILE *fp, const char *name, const char *val,
1113 				void *priv __attribute__((unused)))
1114 {
1115 	return fprintf(fp, "  %-32s %s\n", name, val);
1116 }
1117 
1118 static int __perf_evsel__open(struct perf_evsel *evsel, struct cpu_map *cpus,
1119 			      struct thread_map *threads)
1120 {
1121 	int cpu, thread, nthreads;
1122 	unsigned long flags = PERF_FLAG_FD_CLOEXEC;
1123 	int pid = -1, err;
1124 	enum { NO_CHANGE, SET_TO_MAX, INCREASED_MAX } set_rlimit = NO_CHANGE;
1125 
1126 	if (evsel->system_wide)
1127 		nthreads = 1;
1128 	else
1129 		nthreads = threads->nr;
1130 
1131 	if (evsel->fd == NULL &&
1132 	    perf_evsel__alloc_fd(evsel, cpus->nr, nthreads) < 0)
1133 		return -ENOMEM;
1134 
1135 	if (evsel->cgrp) {
1136 		flags |= PERF_FLAG_PID_CGROUP;
1137 		pid = evsel->cgrp->fd;
1138 	}
1139 
1140 fallback_missing_features:
1141 	if (perf_missing_features.clockid_wrong)
1142 		evsel->attr.clockid = CLOCK_MONOTONIC; /* should always work */
1143 	if (perf_missing_features.clockid) {
1144 		evsel->attr.use_clockid = 0;
1145 		evsel->attr.clockid = 0;
1146 	}
1147 	if (perf_missing_features.cloexec)
1148 		flags &= ~(unsigned long)PERF_FLAG_FD_CLOEXEC;
1149 	if (perf_missing_features.mmap2)
1150 		evsel->attr.mmap2 = 0;
1151 	if (perf_missing_features.exclude_guest)
1152 		evsel->attr.exclude_guest = evsel->attr.exclude_host = 0;
1153 retry_sample_id:
1154 	if (perf_missing_features.sample_id_all)
1155 		evsel->attr.sample_id_all = 0;
1156 
1157 	if (verbose >= 2) {
1158 		fprintf(stderr, "%.60s\n", graph_dotted_line);
1159 		fprintf(stderr, "perf_event_attr:\n");
1160 		perf_event_attr__fprintf(stderr, &evsel->attr, __open_attr__fprintf, NULL);
1161 		fprintf(stderr, "%.60s\n", graph_dotted_line);
1162 	}
1163 
1164 	for (cpu = 0; cpu < cpus->nr; cpu++) {
1165 
1166 		for (thread = 0; thread < nthreads; thread++) {
1167 			int group_fd;
1168 
1169 			if (!evsel->cgrp && !evsel->system_wide)
1170 				pid = thread_map__pid(threads, thread);
1171 
1172 			group_fd = get_group_fd(evsel, cpu, thread);
1173 retry_open:
1174 			pr_debug2("sys_perf_event_open: pid %d  cpu %d  group_fd %d  flags %#lx\n",
1175 				  pid, cpus->map[cpu], group_fd, flags);
1176 
1177 			FD(evsel, cpu, thread) = sys_perf_event_open(&evsel->attr,
1178 								     pid,
1179 								     cpus->map[cpu],
1180 								     group_fd, flags);
1181 			if (FD(evsel, cpu, thread) < 0) {
1182 				err = -errno;
1183 				pr_debug2("sys_perf_event_open failed, error %d\n",
1184 					  err);
1185 				goto try_fallback;
1186 			}
1187 			set_rlimit = NO_CHANGE;
1188 
1189 			/*
1190 			 * If we succeeded but had to kill clockid, fail and
1191 			 * have perf_evsel__open_strerror() print us a nice
1192 			 * error.
1193 			 */
1194 			if (perf_missing_features.clockid ||
1195 			    perf_missing_features.clockid_wrong) {
1196 				err = -EINVAL;
1197 				goto out_close;
1198 			}
1199 		}
1200 	}
1201 
1202 	return 0;
1203 
1204 try_fallback:
1205 	/*
1206 	 * perf stat needs between 5 and 22 fds per CPU. When we run out
1207 	 * of them try to increase the limits.
1208 	 */
1209 	if (err == -EMFILE && set_rlimit < INCREASED_MAX) {
1210 		struct rlimit l;
1211 		int old_errno = errno;
1212 
1213 		if (getrlimit(RLIMIT_NOFILE, &l) == 0) {
1214 			if (set_rlimit == NO_CHANGE)
1215 				l.rlim_cur = l.rlim_max;
1216 			else {
1217 				l.rlim_cur = l.rlim_max + 1000;
1218 				l.rlim_max = l.rlim_cur;
1219 			}
1220 			if (setrlimit(RLIMIT_NOFILE, &l) == 0) {
1221 				set_rlimit++;
1222 				errno = old_errno;
1223 				goto retry_open;
1224 			}
1225 		}
1226 		errno = old_errno;
1227 	}
1228 
1229 	if (err != -EINVAL || cpu > 0 || thread > 0)
1230 		goto out_close;
1231 
1232 	/*
1233 	 * Must probe features in the order they were added to the
1234 	 * perf_event_attr interface.
1235 	 */
1236 	if (!perf_missing_features.clockid_wrong && evsel->attr.use_clockid) {
1237 		perf_missing_features.clockid_wrong = true;
1238 		goto fallback_missing_features;
1239 	} else if (!perf_missing_features.clockid && evsel->attr.use_clockid) {
1240 		perf_missing_features.clockid = true;
1241 		goto fallback_missing_features;
1242 	} else if (!perf_missing_features.cloexec && (flags & PERF_FLAG_FD_CLOEXEC)) {
1243 		perf_missing_features.cloexec = true;
1244 		goto fallback_missing_features;
1245 	} else if (!perf_missing_features.mmap2 && evsel->attr.mmap2) {
1246 		perf_missing_features.mmap2 = true;
1247 		goto fallback_missing_features;
1248 	} else if (!perf_missing_features.exclude_guest &&
1249 		   (evsel->attr.exclude_guest || evsel->attr.exclude_host)) {
1250 		perf_missing_features.exclude_guest = true;
1251 		goto fallback_missing_features;
1252 	} else if (!perf_missing_features.sample_id_all) {
1253 		perf_missing_features.sample_id_all = true;
1254 		goto retry_sample_id;
1255 	}
1256 
1257 out_close:
1258 	do {
1259 		while (--thread >= 0) {
1260 			close(FD(evsel, cpu, thread));
1261 			FD(evsel, cpu, thread) = -1;
1262 		}
1263 		thread = nthreads;
1264 	} while (--cpu >= 0);
1265 	return err;
1266 }
1267 
1268 void perf_evsel__close(struct perf_evsel *evsel, int ncpus, int nthreads)
1269 {
1270 	if (evsel->fd == NULL)
1271 		return;
1272 
1273 	perf_evsel__close_fd(evsel, ncpus, nthreads);
1274 	perf_evsel__free_fd(evsel);
1275 }
1276 
1277 static struct {
1278 	struct cpu_map map;
1279 	int cpus[1];
1280 } empty_cpu_map = {
1281 	.map.nr	= 1,
1282 	.cpus	= { -1, },
1283 };
1284 
1285 static struct {
1286 	struct thread_map map;
1287 	int threads[1];
1288 } empty_thread_map = {
1289 	.map.nr	 = 1,
1290 	.threads = { -1, },
1291 };
1292 
1293 int perf_evsel__open(struct perf_evsel *evsel, struct cpu_map *cpus,
1294 		     struct thread_map *threads)
1295 {
1296 	if (cpus == NULL) {
1297 		/* Work around old compiler warnings about strict aliasing */
1298 		cpus = &empty_cpu_map.map;
1299 	}
1300 
1301 	if (threads == NULL)
1302 		threads = &empty_thread_map.map;
1303 
1304 	return __perf_evsel__open(evsel, cpus, threads);
1305 }
1306 
1307 int perf_evsel__open_per_cpu(struct perf_evsel *evsel,
1308 			     struct cpu_map *cpus)
1309 {
1310 	return __perf_evsel__open(evsel, cpus, &empty_thread_map.map);
1311 }
1312 
1313 int perf_evsel__open_per_thread(struct perf_evsel *evsel,
1314 				struct thread_map *threads)
1315 {
1316 	return __perf_evsel__open(evsel, &empty_cpu_map.map, threads);
1317 }
1318 
1319 static int perf_evsel__parse_id_sample(const struct perf_evsel *evsel,
1320 				       const union perf_event *event,
1321 				       struct perf_sample *sample)
1322 {
1323 	u64 type = evsel->attr.sample_type;
1324 	const u64 *array = event->sample.array;
1325 	bool swapped = evsel->needs_swap;
1326 	union u64_swap u;
1327 
1328 	array += ((event->header.size -
1329 		   sizeof(event->header)) / sizeof(u64)) - 1;
1330 
1331 	if (type & PERF_SAMPLE_IDENTIFIER) {
1332 		sample->id = *array;
1333 		array--;
1334 	}
1335 
1336 	if (type & PERF_SAMPLE_CPU) {
1337 		u.val64 = *array;
1338 		if (swapped) {
1339 			/* undo swap of u64, then swap on individual u32s */
1340 			u.val64 = bswap_64(u.val64);
1341 			u.val32[0] = bswap_32(u.val32[0]);
1342 		}
1343 
1344 		sample->cpu = u.val32[0];
1345 		array--;
1346 	}
1347 
1348 	if (type & PERF_SAMPLE_STREAM_ID) {
1349 		sample->stream_id = *array;
1350 		array--;
1351 	}
1352 
1353 	if (type & PERF_SAMPLE_ID) {
1354 		sample->id = *array;
1355 		array--;
1356 	}
1357 
1358 	if (type & PERF_SAMPLE_TIME) {
1359 		sample->time = *array;
1360 		array--;
1361 	}
1362 
1363 	if (type & PERF_SAMPLE_TID) {
1364 		u.val64 = *array;
1365 		if (swapped) {
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 
1372 		sample->pid = u.val32[0];
1373 		sample->tid = u.val32[1];
1374 		array--;
1375 	}
1376 
1377 	return 0;
1378 }
1379 
1380 static inline bool overflow(const void *endp, u16 max_size, const void *offset,
1381 			    u64 size)
1382 {
1383 	return size > max_size || offset + size > endp;
1384 }
1385 
1386 #define OVERFLOW_CHECK(offset, size, max_size)				\
1387 	do {								\
1388 		if (overflow(endp, (max_size), (offset), (size)))	\
1389 			return -EFAULT;					\
1390 	} while (0)
1391 
1392 #define OVERFLOW_CHECK_u64(offset) \
1393 	OVERFLOW_CHECK(offset, sizeof(u64), sizeof(u64))
1394 
1395 int perf_evsel__parse_sample(struct perf_evsel *evsel, union perf_event *event,
1396 			     struct perf_sample *data)
1397 {
1398 	u64 type = evsel->attr.sample_type;
1399 	bool swapped = evsel->needs_swap;
1400 	const u64 *array;
1401 	u16 max_size = event->header.size;
1402 	const void *endp = (void *)event + max_size;
1403 	u64 sz;
1404 
1405 	/*
1406 	 * used for cross-endian analysis. See git commit 65014ab3
1407 	 * for why this goofiness is needed.
1408 	 */
1409 	union u64_swap u;
1410 
1411 	memset(data, 0, sizeof(*data));
1412 	data->cpu = data->pid = data->tid = -1;
1413 	data->stream_id = data->id = data->time = -1ULL;
1414 	data->period = evsel->attr.sample_period;
1415 	data->weight = 0;
1416 
1417 	if (event->header.type != PERF_RECORD_SAMPLE) {
1418 		if (!evsel->attr.sample_id_all)
1419 			return 0;
1420 		return perf_evsel__parse_id_sample(evsel, event, data);
1421 	}
1422 
1423 	array = event->sample.array;
1424 
1425 	/*
1426 	 * The evsel's sample_size is based on PERF_SAMPLE_MASK which includes
1427 	 * up to PERF_SAMPLE_PERIOD.  After that overflow() must be used to
1428 	 * check the format does not go past the end of the event.
1429 	 */
1430 	if (evsel->sample_size + sizeof(event->header) > event->header.size)
1431 		return -EFAULT;
1432 
1433 	data->id = -1ULL;
1434 	if (type & PERF_SAMPLE_IDENTIFIER) {
1435 		data->id = *array;
1436 		array++;
1437 	}
1438 
1439 	if (type & PERF_SAMPLE_IP) {
1440 		data->ip = *array;
1441 		array++;
1442 	}
1443 
1444 	if (type & PERF_SAMPLE_TID) {
1445 		u.val64 = *array;
1446 		if (swapped) {
1447 			/* undo swap of u64, then swap on individual u32s */
1448 			u.val64 = bswap_64(u.val64);
1449 			u.val32[0] = bswap_32(u.val32[0]);
1450 			u.val32[1] = bswap_32(u.val32[1]);
1451 		}
1452 
1453 		data->pid = u.val32[0];
1454 		data->tid = u.val32[1];
1455 		array++;
1456 	}
1457 
1458 	if (type & PERF_SAMPLE_TIME) {
1459 		data->time = *array;
1460 		array++;
1461 	}
1462 
1463 	data->addr = 0;
1464 	if (type & PERF_SAMPLE_ADDR) {
1465 		data->addr = *array;
1466 		array++;
1467 	}
1468 
1469 	if (type & PERF_SAMPLE_ID) {
1470 		data->id = *array;
1471 		array++;
1472 	}
1473 
1474 	if (type & PERF_SAMPLE_STREAM_ID) {
1475 		data->stream_id = *array;
1476 		array++;
1477 	}
1478 
1479 	if (type & PERF_SAMPLE_CPU) {
1480 
1481 		u.val64 = *array;
1482 		if (swapped) {
1483 			/* undo swap of u64, then swap on individual u32s */
1484 			u.val64 = bswap_64(u.val64);
1485 			u.val32[0] = bswap_32(u.val32[0]);
1486 		}
1487 
1488 		data->cpu = u.val32[0];
1489 		array++;
1490 	}
1491 
1492 	if (type & PERF_SAMPLE_PERIOD) {
1493 		data->period = *array;
1494 		array++;
1495 	}
1496 
1497 	if (type & PERF_SAMPLE_READ) {
1498 		u64 read_format = evsel->attr.read_format;
1499 
1500 		OVERFLOW_CHECK_u64(array);
1501 		if (read_format & PERF_FORMAT_GROUP)
1502 			data->read.group.nr = *array;
1503 		else
1504 			data->read.one.value = *array;
1505 
1506 		array++;
1507 
1508 		if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) {
1509 			OVERFLOW_CHECK_u64(array);
1510 			data->read.time_enabled = *array;
1511 			array++;
1512 		}
1513 
1514 		if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) {
1515 			OVERFLOW_CHECK_u64(array);
1516 			data->read.time_running = *array;
1517 			array++;
1518 		}
1519 
1520 		/* PERF_FORMAT_ID is forced for PERF_SAMPLE_READ */
1521 		if (read_format & PERF_FORMAT_GROUP) {
1522 			const u64 max_group_nr = UINT64_MAX /
1523 					sizeof(struct sample_read_value);
1524 
1525 			if (data->read.group.nr > max_group_nr)
1526 				return -EFAULT;
1527 			sz = data->read.group.nr *
1528 			     sizeof(struct sample_read_value);
1529 			OVERFLOW_CHECK(array, sz, max_size);
1530 			data->read.group.values =
1531 					(struct sample_read_value *)array;
1532 			array = (void *)array + sz;
1533 		} else {
1534 			OVERFLOW_CHECK_u64(array);
1535 			data->read.one.id = *array;
1536 			array++;
1537 		}
1538 	}
1539 
1540 	if (type & PERF_SAMPLE_CALLCHAIN) {
1541 		const u64 max_callchain_nr = UINT64_MAX / sizeof(u64);
1542 
1543 		OVERFLOW_CHECK_u64(array);
1544 		data->callchain = (struct ip_callchain *)array++;
1545 		if (data->callchain->nr > max_callchain_nr)
1546 			return -EFAULT;
1547 		sz = data->callchain->nr * sizeof(u64);
1548 		OVERFLOW_CHECK(array, sz, max_size);
1549 		array = (void *)array + sz;
1550 	}
1551 
1552 	if (type & PERF_SAMPLE_RAW) {
1553 		OVERFLOW_CHECK_u64(array);
1554 		u.val64 = *array;
1555 		if (WARN_ONCE(swapped,
1556 			      "Endianness of raw data not corrected!\n")) {
1557 			/* undo swap of u64, then swap on individual u32s */
1558 			u.val64 = bswap_64(u.val64);
1559 			u.val32[0] = bswap_32(u.val32[0]);
1560 			u.val32[1] = bswap_32(u.val32[1]);
1561 		}
1562 		data->raw_size = u.val32[0];
1563 		array = (void *)array + sizeof(u32);
1564 
1565 		OVERFLOW_CHECK(array, data->raw_size, max_size);
1566 		data->raw_data = (void *)array;
1567 		array = (void *)array + data->raw_size;
1568 	}
1569 
1570 	if (type & PERF_SAMPLE_BRANCH_STACK) {
1571 		const u64 max_branch_nr = UINT64_MAX /
1572 					  sizeof(struct branch_entry);
1573 
1574 		OVERFLOW_CHECK_u64(array);
1575 		data->branch_stack = (struct branch_stack *)array++;
1576 
1577 		if (data->branch_stack->nr > max_branch_nr)
1578 			return -EFAULT;
1579 		sz = data->branch_stack->nr * sizeof(struct branch_entry);
1580 		OVERFLOW_CHECK(array, sz, max_size);
1581 		array = (void *)array + sz;
1582 	}
1583 
1584 	if (type & PERF_SAMPLE_REGS_USER) {
1585 		OVERFLOW_CHECK_u64(array);
1586 		data->user_regs.abi = *array;
1587 		array++;
1588 
1589 		if (data->user_regs.abi) {
1590 			u64 mask = evsel->attr.sample_regs_user;
1591 
1592 			sz = hweight_long(mask) * sizeof(u64);
1593 			OVERFLOW_CHECK(array, sz, max_size);
1594 			data->user_regs.mask = mask;
1595 			data->user_regs.regs = (u64 *)array;
1596 			array = (void *)array + sz;
1597 		}
1598 	}
1599 
1600 	if (type & PERF_SAMPLE_STACK_USER) {
1601 		OVERFLOW_CHECK_u64(array);
1602 		sz = *array++;
1603 
1604 		data->user_stack.offset = ((char *)(array - 1)
1605 					  - (char *) event);
1606 
1607 		if (!sz) {
1608 			data->user_stack.size = 0;
1609 		} else {
1610 			OVERFLOW_CHECK(array, sz, max_size);
1611 			data->user_stack.data = (char *)array;
1612 			array = (void *)array + sz;
1613 			OVERFLOW_CHECK_u64(array);
1614 			data->user_stack.size = *array++;
1615 			if (WARN_ONCE(data->user_stack.size > sz,
1616 				      "user stack dump failure\n"))
1617 				return -EFAULT;
1618 		}
1619 	}
1620 
1621 	data->weight = 0;
1622 	if (type & PERF_SAMPLE_WEIGHT) {
1623 		OVERFLOW_CHECK_u64(array);
1624 		data->weight = *array;
1625 		array++;
1626 	}
1627 
1628 	data->data_src = PERF_MEM_DATA_SRC_NONE;
1629 	if (type & PERF_SAMPLE_DATA_SRC) {
1630 		OVERFLOW_CHECK_u64(array);
1631 		data->data_src = *array;
1632 		array++;
1633 	}
1634 
1635 	data->transaction = 0;
1636 	if (type & PERF_SAMPLE_TRANSACTION) {
1637 		OVERFLOW_CHECK_u64(array);
1638 		data->transaction = *array;
1639 		array++;
1640 	}
1641 
1642 	data->intr_regs.abi = PERF_SAMPLE_REGS_ABI_NONE;
1643 	if (type & PERF_SAMPLE_REGS_INTR) {
1644 		OVERFLOW_CHECK_u64(array);
1645 		data->intr_regs.abi = *array;
1646 		array++;
1647 
1648 		if (data->intr_regs.abi != PERF_SAMPLE_REGS_ABI_NONE) {
1649 			u64 mask = evsel->attr.sample_regs_intr;
1650 
1651 			sz = hweight_long(mask) * sizeof(u64);
1652 			OVERFLOW_CHECK(array, sz, max_size);
1653 			data->intr_regs.mask = mask;
1654 			data->intr_regs.regs = (u64 *)array;
1655 			array = (void *)array + sz;
1656 		}
1657 	}
1658 
1659 	return 0;
1660 }
1661 
1662 size_t perf_event__sample_event_size(const struct perf_sample *sample, u64 type,
1663 				     u64 read_format)
1664 {
1665 	size_t sz, result = sizeof(struct sample_event);
1666 
1667 	if (type & PERF_SAMPLE_IDENTIFIER)
1668 		result += sizeof(u64);
1669 
1670 	if (type & PERF_SAMPLE_IP)
1671 		result += sizeof(u64);
1672 
1673 	if (type & PERF_SAMPLE_TID)
1674 		result += sizeof(u64);
1675 
1676 	if (type & PERF_SAMPLE_TIME)
1677 		result += sizeof(u64);
1678 
1679 	if (type & PERF_SAMPLE_ADDR)
1680 		result += sizeof(u64);
1681 
1682 	if (type & PERF_SAMPLE_ID)
1683 		result += sizeof(u64);
1684 
1685 	if (type & PERF_SAMPLE_STREAM_ID)
1686 		result += sizeof(u64);
1687 
1688 	if (type & PERF_SAMPLE_CPU)
1689 		result += sizeof(u64);
1690 
1691 	if (type & PERF_SAMPLE_PERIOD)
1692 		result += sizeof(u64);
1693 
1694 	if (type & PERF_SAMPLE_READ) {
1695 		result += sizeof(u64);
1696 		if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED)
1697 			result += sizeof(u64);
1698 		if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING)
1699 			result += sizeof(u64);
1700 		/* PERF_FORMAT_ID is forced for PERF_SAMPLE_READ */
1701 		if (read_format & PERF_FORMAT_GROUP) {
1702 			sz = sample->read.group.nr *
1703 			     sizeof(struct sample_read_value);
1704 			result += sz;
1705 		} else {
1706 			result += sizeof(u64);
1707 		}
1708 	}
1709 
1710 	if (type & PERF_SAMPLE_CALLCHAIN) {
1711 		sz = (sample->callchain->nr + 1) * sizeof(u64);
1712 		result += sz;
1713 	}
1714 
1715 	if (type & PERF_SAMPLE_RAW) {
1716 		result += sizeof(u32);
1717 		result += sample->raw_size;
1718 	}
1719 
1720 	if (type & PERF_SAMPLE_BRANCH_STACK) {
1721 		sz = sample->branch_stack->nr * sizeof(struct branch_entry);
1722 		sz += sizeof(u64);
1723 		result += sz;
1724 	}
1725 
1726 	if (type & PERF_SAMPLE_REGS_USER) {
1727 		if (sample->user_regs.abi) {
1728 			result += sizeof(u64);
1729 			sz = hweight_long(sample->user_regs.mask) * sizeof(u64);
1730 			result += sz;
1731 		} else {
1732 			result += sizeof(u64);
1733 		}
1734 	}
1735 
1736 	if (type & PERF_SAMPLE_STACK_USER) {
1737 		sz = sample->user_stack.size;
1738 		result += sizeof(u64);
1739 		if (sz) {
1740 			result += sz;
1741 			result += sizeof(u64);
1742 		}
1743 	}
1744 
1745 	if (type & PERF_SAMPLE_WEIGHT)
1746 		result += sizeof(u64);
1747 
1748 	if (type & PERF_SAMPLE_DATA_SRC)
1749 		result += sizeof(u64);
1750 
1751 	if (type & PERF_SAMPLE_TRANSACTION)
1752 		result += sizeof(u64);
1753 
1754 	if (type & PERF_SAMPLE_REGS_INTR) {
1755 		if (sample->intr_regs.abi) {
1756 			result += sizeof(u64);
1757 			sz = hweight_long(sample->intr_regs.mask) * sizeof(u64);
1758 			result += sz;
1759 		} else {
1760 			result += sizeof(u64);
1761 		}
1762 	}
1763 
1764 	return result;
1765 }
1766 
1767 int perf_event__synthesize_sample(union perf_event *event, u64 type,
1768 				  u64 read_format,
1769 				  const struct perf_sample *sample,
1770 				  bool swapped)
1771 {
1772 	u64 *array;
1773 	size_t sz;
1774 	/*
1775 	 * used for cross-endian analysis. See git commit 65014ab3
1776 	 * for why this goofiness is needed.
1777 	 */
1778 	union u64_swap u;
1779 
1780 	array = event->sample.array;
1781 
1782 	if (type & PERF_SAMPLE_IDENTIFIER) {
1783 		*array = sample->id;
1784 		array++;
1785 	}
1786 
1787 	if (type & PERF_SAMPLE_IP) {
1788 		*array = sample->ip;
1789 		array++;
1790 	}
1791 
1792 	if (type & PERF_SAMPLE_TID) {
1793 		u.val32[0] = sample->pid;
1794 		u.val32[1] = sample->tid;
1795 		if (swapped) {
1796 			/*
1797 			 * Inverse of what is done in perf_evsel__parse_sample
1798 			 */
1799 			u.val32[0] = bswap_32(u.val32[0]);
1800 			u.val32[1] = bswap_32(u.val32[1]);
1801 			u.val64 = bswap_64(u.val64);
1802 		}
1803 
1804 		*array = u.val64;
1805 		array++;
1806 	}
1807 
1808 	if (type & PERF_SAMPLE_TIME) {
1809 		*array = sample->time;
1810 		array++;
1811 	}
1812 
1813 	if (type & PERF_SAMPLE_ADDR) {
1814 		*array = sample->addr;
1815 		array++;
1816 	}
1817 
1818 	if (type & PERF_SAMPLE_ID) {
1819 		*array = sample->id;
1820 		array++;
1821 	}
1822 
1823 	if (type & PERF_SAMPLE_STREAM_ID) {
1824 		*array = sample->stream_id;
1825 		array++;
1826 	}
1827 
1828 	if (type & PERF_SAMPLE_CPU) {
1829 		u.val32[0] = sample->cpu;
1830 		if (swapped) {
1831 			/*
1832 			 * Inverse of what is done in perf_evsel__parse_sample
1833 			 */
1834 			u.val32[0] = bswap_32(u.val32[0]);
1835 			u.val64 = bswap_64(u.val64);
1836 		}
1837 		*array = u.val64;
1838 		array++;
1839 	}
1840 
1841 	if (type & PERF_SAMPLE_PERIOD) {
1842 		*array = sample->period;
1843 		array++;
1844 	}
1845 
1846 	if (type & PERF_SAMPLE_READ) {
1847 		if (read_format & PERF_FORMAT_GROUP)
1848 			*array = sample->read.group.nr;
1849 		else
1850 			*array = sample->read.one.value;
1851 		array++;
1852 
1853 		if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) {
1854 			*array = sample->read.time_enabled;
1855 			array++;
1856 		}
1857 
1858 		if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) {
1859 			*array = sample->read.time_running;
1860 			array++;
1861 		}
1862 
1863 		/* PERF_FORMAT_ID is forced for PERF_SAMPLE_READ */
1864 		if (read_format & PERF_FORMAT_GROUP) {
1865 			sz = sample->read.group.nr *
1866 			     sizeof(struct sample_read_value);
1867 			memcpy(array, sample->read.group.values, sz);
1868 			array = (void *)array + sz;
1869 		} else {
1870 			*array = sample->read.one.id;
1871 			array++;
1872 		}
1873 	}
1874 
1875 	if (type & PERF_SAMPLE_CALLCHAIN) {
1876 		sz = (sample->callchain->nr + 1) * sizeof(u64);
1877 		memcpy(array, sample->callchain, sz);
1878 		array = (void *)array + sz;
1879 	}
1880 
1881 	if (type & PERF_SAMPLE_RAW) {
1882 		u.val32[0] = sample->raw_size;
1883 		if (WARN_ONCE(swapped,
1884 			      "Endianness of raw data not corrected!\n")) {
1885 			/*
1886 			 * Inverse of what is done in perf_evsel__parse_sample
1887 			 */
1888 			u.val32[0] = bswap_32(u.val32[0]);
1889 			u.val32[1] = bswap_32(u.val32[1]);
1890 			u.val64 = bswap_64(u.val64);
1891 		}
1892 		*array = u.val64;
1893 		array = (void *)array + sizeof(u32);
1894 
1895 		memcpy(array, sample->raw_data, sample->raw_size);
1896 		array = (void *)array + sample->raw_size;
1897 	}
1898 
1899 	if (type & PERF_SAMPLE_BRANCH_STACK) {
1900 		sz = sample->branch_stack->nr * sizeof(struct branch_entry);
1901 		sz += sizeof(u64);
1902 		memcpy(array, sample->branch_stack, sz);
1903 		array = (void *)array + sz;
1904 	}
1905 
1906 	if (type & PERF_SAMPLE_REGS_USER) {
1907 		if (sample->user_regs.abi) {
1908 			*array++ = sample->user_regs.abi;
1909 			sz = hweight_long(sample->user_regs.mask) * sizeof(u64);
1910 			memcpy(array, sample->user_regs.regs, sz);
1911 			array = (void *)array + sz;
1912 		} else {
1913 			*array++ = 0;
1914 		}
1915 	}
1916 
1917 	if (type & PERF_SAMPLE_STACK_USER) {
1918 		sz = sample->user_stack.size;
1919 		*array++ = sz;
1920 		if (sz) {
1921 			memcpy(array, sample->user_stack.data, sz);
1922 			array = (void *)array + sz;
1923 			*array++ = sz;
1924 		}
1925 	}
1926 
1927 	if (type & PERF_SAMPLE_WEIGHT) {
1928 		*array = sample->weight;
1929 		array++;
1930 	}
1931 
1932 	if (type & PERF_SAMPLE_DATA_SRC) {
1933 		*array = sample->data_src;
1934 		array++;
1935 	}
1936 
1937 	if (type & PERF_SAMPLE_TRANSACTION) {
1938 		*array = sample->transaction;
1939 		array++;
1940 	}
1941 
1942 	if (type & PERF_SAMPLE_REGS_INTR) {
1943 		if (sample->intr_regs.abi) {
1944 			*array++ = sample->intr_regs.abi;
1945 			sz = hweight_long(sample->intr_regs.mask) * sizeof(u64);
1946 			memcpy(array, sample->intr_regs.regs, sz);
1947 			array = (void *)array + sz;
1948 		} else {
1949 			*array++ = 0;
1950 		}
1951 	}
1952 
1953 	return 0;
1954 }
1955 
1956 struct format_field *perf_evsel__field(struct perf_evsel *evsel, const char *name)
1957 {
1958 	return pevent_find_field(evsel->tp_format, name);
1959 }
1960 
1961 void *perf_evsel__rawptr(struct perf_evsel *evsel, struct perf_sample *sample,
1962 			 const char *name)
1963 {
1964 	struct format_field *field = perf_evsel__field(evsel, name);
1965 	int offset;
1966 
1967 	if (!field)
1968 		return NULL;
1969 
1970 	offset = field->offset;
1971 
1972 	if (field->flags & FIELD_IS_DYNAMIC) {
1973 		offset = *(int *)(sample->raw_data + field->offset);
1974 		offset &= 0xffff;
1975 	}
1976 
1977 	return sample->raw_data + offset;
1978 }
1979 
1980 u64 perf_evsel__intval(struct perf_evsel *evsel, struct perf_sample *sample,
1981 		       const char *name)
1982 {
1983 	struct format_field *field = perf_evsel__field(evsel, name);
1984 	void *ptr;
1985 	u64 value;
1986 
1987 	if (!field)
1988 		return 0;
1989 
1990 	ptr = sample->raw_data + field->offset;
1991 
1992 	switch (field->size) {
1993 	case 1:
1994 		return *(u8 *)ptr;
1995 	case 2:
1996 		value = *(u16 *)ptr;
1997 		break;
1998 	case 4:
1999 		value = *(u32 *)ptr;
2000 		break;
2001 	case 8:
2002 		memcpy(&value, ptr, sizeof(u64));
2003 		break;
2004 	default:
2005 		return 0;
2006 	}
2007 
2008 	if (!evsel->needs_swap)
2009 		return value;
2010 
2011 	switch (field->size) {
2012 	case 2:
2013 		return bswap_16(value);
2014 	case 4:
2015 		return bswap_32(value);
2016 	case 8:
2017 		return bswap_64(value);
2018 	default:
2019 		return 0;
2020 	}
2021 
2022 	return 0;
2023 }
2024 
2025 static int comma_fprintf(FILE *fp, bool *first, const char *fmt, ...)
2026 {
2027 	va_list args;
2028 	int ret = 0;
2029 
2030 	if (!*first) {
2031 		ret += fprintf(fp, ",");
2032 	} else {
2033 		ret += fprintf(fp, ":");
2034 		*first = false;
2035 	}
2036 
2037 	va_start(args, fmt);
2038 	ret += vfprintf(fp, fmt, args);
2039 	va_end(args);
2040 	return ret;
2041 }
2042 
2043 static int __print_attr__fprintf(FILE *fp, const char *name, const char *val, void *priv)
2044 {
2045 	return comma_fprintf(fp, (bool *)priv, " %s: %s", name, val);
2046 }
2047 
2048 int perf_evsel__fprintf(struct perf_evsel *evsel,
2049 			struct perf_attr_details *details, FILE *fp)
2050 {
2051 	bool first = true;
2052 	int printed = 0;
2053 
2054 	if (details->event_group) {
2055 		struct perf_evsel *pos;
2056 
2057 		if (!perf_evsel__is_group_leader(evsel))
2058 			return 0;
2059 
2060 		if (evsel->nr_members > 1)
2061 			printed += fprintf(fp, "%s{", evsel->group_name ?: "");
2062 
2063 		printed += fprintf(fp, "%s", perf_evsel__name(evsel));
2064 		for_each_group_member(pos, evsel)
2065 			printed += fprintf(fp, ",%s", perf_evsel__name(pos));
2066 
2067 		if (evsel->nr_members > 1)
2068 			printed += fprintf(fp, "}");
2069 		goto out;
2070 	}
2071 
2072 	printed += fprintf(fp, "%s", perf_evsel__name(evsel));
2073 
2074 	if (details->verbose) {
2075 		printed += perf_event_attr__fprintf(fp, &evsel->attr,
2076 						    __print_attr__fprintf, &first);
2077 	} else if (details->freq) {
2078 		printed += comma_fprintf(fp, &first, " sample_freq=%" PRIu64,
2079 					 (u64)evsel->attr.sample_freq);
2080 	}
2081 out:
2082 	fputc('\n', fp);
2083 	return ++printed;
2084 }
2085 
2086 bool perf_evsel__fallback(struct perf_evsel *evsel, int err,
2087 			  char *msg, size_t msgsize)
2088 {
2089 	if ((err == ENOENT || err == ENXIO || err == ENODEV) &&
2090 	    evsel->attr.type   == PERF_TYPE_HARDWARE &&
2091 	    evsel->attr.config == PERF_COUNT_HW_CPU_CYCLES) {
2092 		/*
2093 		 * If it's cycles then fall back to hrtimer based
2094 		 * cpu-clock-tick sw counter, which is always available even if
2095 		 * no PMU support.
2096 		 *
2097 		 * PPC returns ENXIO until 2.6.37 (behavior changed with commit
2098 		 * b0a873e).
2099 		 */
2100 		scnprintf(msg, msgsize, "%s",
2101 "The cycles event is not supported, trying to fall back to cpu-clock-ticks");
2102 
2103 		evsel->attr.type   = PERF_TYPE_SOFTWARE;
2104 		evsel->attr.config = PERF_COUNT_SW_CPU_CLOCK;
2105 
2106 		zfree(&evsel->name);
2107 		return true;
2108 	}
2109 
2110 	return false;
2111 }
2112 
2113 int perf_evsel__open_strerror(struct perf_evsel *evsel, struct target *target,
2114 			      int err, char *msg, size_t size)
2115 {
2116 	char sbuf[STRERR_BUFSIZE];
2117 
2118 	switch (err) {
2119 	case EPERM:
2120 	case EACCES:
2121 		return scnprintf(msg, size,
2122 		 "You may not have permission to collect %sstats.\n"
2123 		 "Consider tweaking /proc/sys/kernel/perf_event_paranoid:\n"
2124 		 " -1 - Not paranoid at all\n"
2125 		 "  0 - Disallow raw tracepoint access for unpriv\n"
2126 		 "  1 - Disallow cpu events for unpriv\n"
2127 		 "  2 - Disallow kernel profiling for unpriv",
2128 				 target->system_wide ? "system-wide " : "");
2129 	case ENOENT:
2130 		return scnprintf(msg, size, "The %s event is not supported.",
2131 				 perf_evsel__name(evsel));
2132 	case EMFILE:
2133 		return scnprintf(msg, size, "%s",
2134 			 "Too many events are opened.\n"
2135 			 "Probably the maximum number of open file descriptors has been reached.\n"
2136 			 "Hint: Try again after reducing the number of events.\n"
2137 			 "Hint: Try increasing the limit with 'ulimit -n <limit>'");
2138 	case ENODEV:
2139 		if (target->cpu_list)
2140 			return scnprintf(msg, size, "%s",
2141 	 "No such device - did you specify an out-of-range profile CPU?\n");
2142 		break;
2143 	case EOPNOTSUPP:
2144 		if (evsel->attr.precise_ip)
2145 			return scnprintf(msg, size, "%s",
2146 	"\'precise\' request may not be supported. Try removing 'p' modifier.");
2147 #if defined(__i386__) || defined(__x86_64__)
2148 		if (evsel->attr.type == PERF_TYPE_HARDWARE)
2149 			return scnprintf(msg, size, "%s",
2150 	"No hardware sampling interrupt available.\n"
2151 	"No APIC? If so then you can boot the kernel with the \"lapic\" boot parameter to force-enable it.");
2152 #endif
2153 		break;
2154 	case EBUSY:
2155 		if (find_process("oprofiled"))
2156 			return scnprintf(msg, size,
2157 	"The PMU counters are busy/taken by another profiler.\n"
2158 	"We found oprofile daemon running, please stop it and try again.");
2159 		break;
2160 	case EINVAL:
2161 		if (perf_missing_features.clockid)
2162 			return scnprintf(msg, size, "clockid feature not supported.");
2163 		if (perf_missing_features.clockid_wrong)
2164 			return scnprintf(msg, size, "wrong clockid (%d).", clockid);
2165 		break;
2166 	default:
2167 		break;
2168 	}
2169 
2170 	return scnprintf(msg, size,
2171 	"The sys_perf_event_open() syscall returned with %d (%s) for event (%s).\n"
2172 	"/bin/dmesg may provide additional information.\n"
2173 	"No CONFIG_PERF_EVENTS=y kernel support configured?\n",
2174 			 err, strerror_r(err, sbuf, sizeof(sbuf)),
2175 			 perf_evsel__name(evsel));
2176 }
2177