xref: /openbmc/linux/tools/perf/util/evsel.c (revision bbecb07f)
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 <errno.h>
12 #include <inttypes.h>
13 #include <linux/bitops.h>
14 #include <api/fs/fs.h>
15 #include <api/fs/tracing_path.h>
16 #include <traceevent/event-parse.h>
17 #include <linux/hw_breakpoint.h>
18 #include <linux/perf_event.h>
19 #include <linux/compiler.h>
20 #include <linux/err.h>
21 #include <sys/ioctl.h>
22 #include <sys/resource.h>
23 #include <sys/types.h>
24 #include <dirent.h>
25 #include "asm/bug.h"
26 #include "callchain.h"
27 #include "cgroup.h"
28 #include "event.h"
29 #include "evsel.h"
30 #include "evlist.h"
31 #include "util.h"
32 #include "cpumap.h"
33 #include "thread_map.h"
34 #include "target.h"
35 #include "perf_regs.h"
36 #include "debug.h"
37 #include "trace-event.h"
38 #include "stat.h"
39 #include "util/parse-branch-options.h"
40 
41 #include "sane_ctype.h"
42 
43 static struct {
44 	bool sample_id_all;
45 	bool exclude_guest;
46 	bool mmap2;
47 	bool cloexec;
48 	bool clockid;
49 	bool clockid_wrong;
50 	bool lbr_flags;
51 	bool write_backward;
52 	bool group_read;
53 } perf_missing_features;
54 
55 static clockid_t clockid;
56 
57 static int perf_evsel__no_extra_init(struct perf_evsel *evsel __maybe_unused)
58 {
59 	return 0;
60 }
61 
62 void __weak test_attr__ready(void) { }
63 
64 static void perf_evsel__no_extra_fini(struct perf_evsel *evsel __maybe_unused)
65 {
66 }
67 
68 static struct {
69 	size_t	size;
70 	int	(*init)(struct perf_evsel *evsel);
71 	void	(*fini)(struct perf_evsel *evsel);
72 } perf_evsel__object = {
73 	.size = sizeof(struct perf_evsel),
74 	.init = perf_evsel__no_extra_init,
75 	.fini = perf_evsel__no_extra_fini,
76 };
77 
78 int perf_evsel__object_config(size_t object_size,
79 			      int (*init)(struct perf_evsel *evsel),
80 			      void (*fini)(struct perf_evsel *evsel))
81 {
82 
83 	if (object_size == 0)
84 		goto set_methods;
85 
86 	if (perf_evsel__object.size > object_size)
87 		return -EINVAL;
88 
89 	perf_evsel__object.size = object_size;
90 
91 set_methods:
92 	if (init != NULL)
93 		perf_evsel__object.init = init;
94 
95 	if (fini != NULL)
96 		perf_evsel__object.fini = fini;
97 
98 	return 0;
99 }
100 
101 #define FD(e, x, y) (*(int *)xyarray__entry(e->fd, x, y))
102 
103 int __perf_evsel__sample_size(u64 sample_type)
104 {
105 	u64 mask = sample_type & PERF_SAMPLE_MASK;
106 	int size = 0;
107 	int i;
108 
109 	for (i = 0; i < 64; i++) {
110 		if (mask & (1ULL << i))
111 			size++;
112 	}
113 
114 	size *= sizeof(u64);
115 
116 	return size;
117 }
118 
119 /**
120  * __perf_evsel__calc_id_pos - calculate id_pos.
121  * @sample_type: sample type
122  *
123  * This function returns the position of the event id (PERF_SAMPLE_ID or
124  * PERF_SAMPLE_IDENTIFIER) in a sample event i.e. in the array of struct
125  * sample_event.
126  */
127 static int __perf_evsel__calc_id_pos(u64 sample_type)
128 {
129 	int idx = 0;
130 
131 	if (sample_type & PERF_SAMPLE_IDENTIFIER)
132 		return 0;
133 
134 	if (!(sample_type & PERF_SAMPLE_ID))
135 		return -1;
136 
137 	if (sample_type & PERF_SAMPLE_IP)
138 		idx += 1;
139 
140 	if (sample_type & PERF_SAMPLE_TID)
141 		idx += 1;
142 
143 	if (sample_type & PERF_SAMPLE_TIME)
144 		idx += 1;
145 
146 	if (sample_type & PERF_SAMPLE_ADDR)
147 		idx += 1;
148 
149 	return idx;
150 }
151 
152 /**
153  * __perf_evsel__calc_is_pos - calculate is_pos.
154  * @sample_type: sample type
155  *
156  * This function returns the position (counting backwards) of the event id
157  * (PERF_SAMPLE_ID or PERF_SAMPLE_IDENTIFIER) in a non-sample event i.e. if
158  * sample_id_all is used there is an id sample appended to non-sample events.
159  */
160 static int __perf_evsel__calc_is_pos(u64 sample_type)
161 {
162 	int idx = 1;
163 
164 	if (sample_type & PERF_SAMPLE_IDENTIFIER)
165 		return 1;
166 
167 	if (!(sample_type & PERF_SAMPLE_ID))
168 		return -1;
169 
170 	if (sample_type & PERF_SAMPLE_CPU)
171 		idx += 1;
172 
173 	if (sample_type & PERF_SAMPLE_STREAM_ID)
174 		idx += 1;
175 
176 	return idx;
177 }
178 
179 void perf_evsel__calc_id_pos(struct perf_evsel *evsel)
180 {
181 	evsel->id_pos = __perf_evsel__calc_id_pos(evsel->attr.sample_type);
182 	evsel->is_pos = __perf_evsel__calc_is_pos(evsel->attr.sample_type);
183 }
184 
185 void __perf_evsel__set_sample_bit(struct perf_evsel *evsel,
186 				  enum perf_event_sample_format bit)
187 {
188 	if (!(evsel->attr.sample_type & bit)) {
189 		evsel->attr.sample_type |= bit;
190 		evsel->sample_size += sizeof(u64);
191 		perf_evsel__calc_id_pos(evsel);
192 	}
193 }
194 
195 void __perf_evsel__reset_sample_bit(struct perf_evsel *evsel,
196 				    enum perf_event_sample_format bit)
197 {
198 	if (evsel->attr.sample_type & bit) {
199 		evsel->attr.sample_type &= ~bit;
200 		evsel->sample_size -= sizeof(u64);
201 		perf_evsel__calc_id_pos(evsel);
202 	}
203 }
204 
205 void perf_evsel__set_sample_id(struct perf_evsel *evsel,
206 			       bool can_sample_identifier)
207 {
208 	if (can_sample_identifier) {
209 		perf_evsel__reset_sample_bit(evsel, ID);
210 		perf_evsel__set_sample_bit(evsel, IDENTIFIER);
211 	} else {
212 		perf_evsel__set_sample_bit(evsel, ID);
213 	}
214 	evsel->attr.read_format |= PERF_FORMAT_ID;
215 }
216 
217 /**
218  * perf_evsel__is_function_event - Return whether given evsel is a function
219  * trace event
220  *
221  * @evsel - evsel selector to be tested
222  *
223  * Return %true if event is function trace event
224  */
225 bool perf_evsel__is_function_event(struct perf_evsel *evsel)
226 {
227 #define FUNCTION_EVENT "ftrace:function"
228 
229 	return evsel->name &&
230 	       !strncmp(FUNCTION_EVENT, evsel->name, sizeof(FUNCTION_EVENT));
231 
232 #undef FUNCTION_EVENT
233 }
234 
235 void perf_evsel__init(struct perf_evsel *evsel,
236 		      struct perf_event_attr *attr, int idx)
237 {
238 	evsel->idx	   = idx;
239 	evsel->tracking	   = !idx;
240 	evsel->attr	   = *attr;
241 	evsel->leader	   = evsel;
242 	evsel->unit	   = "";
243 	evsel->scale	   = 1.0;
244 	evsel->evlist	   = NULL;
245 	evsel->bpf_fd	   = -1;
246 	INIT_LIST_HEAD(&evsel->node);
247 	INIT_LIST_HEAD(&evsel->config_terms);
248 	perf_evsel__object.init(evsel);
249 	evsel->sample_size = __perf_evsel__sample_size(attr->sample_type);
250 	perf_evsel__calc_id_pos(evsel);
251 	evsel->cmdline_group_boundary = false;
252 	evsel->metric_expr   = NULL;
253 	evsel->metric_name   = NULL;
254 	evsel->metric_events = NULL;
255 	evsel->collect_stat  = false;
256 }
257 
258 struct perf_evsel *perf_evsel__new_idx(struct perf_event_attr *attr, int idx)
259 {
260 	struct perf_evsel *evsel = zalloc(perf_evsel__object.size);
261 
262 	if (evsel != NULL)
263 		perf_evsel__init(evsel, attr, idx);
264 
265 	if (perf_evsel__is_bpf_output(evsel)) {
266 		evsel->attr.sample_type |= (PERF_SAMPLE_RAW | PERF_SAMPLE_TIME |
267 					    PERF_SAMPLE_CPU | PERF_SAMPLE_PERIOD),
268 		evsel->attr.sample_period = 1;
269 	}
270 
271 	return evsel;
272 }
273 
274 static bool perf_event_can_profile_kernel(void)
275 {
276 	return geteuid() == 0 || perf_event_paranoid() == -1;
277 }
278 
279 struct perf_evsel *perf_evsel__new_cycles(bool precise)
280 {
281 	struct perf_event_attr attr = {
282 		.type	= PERF_TYPE_HARDWARE,
283 		.config	= PERF_COUNT_HW_CPU_CYCLES,
284 		.exclude_kernel	= !perf_event_can_profile_kernel(),
285 	};
286 	struct perf_evsel *evsel;
287 
288 	event_attr_init(&attr);
289 
290 	if (!precise)
291 		goto new_event;
292 	/*
293 	 * Unnamed union member, not supported as struct member named
294 	 * initializer in older compilers such as gcc 4.4.7
295 	 *
296 	 * Just for probing the precise_ip:
297 	 */
298 	attr.sample_period = 1;
299 
300 	perf_event_attr__set_max_precise_ip(&attr);
301 	/*
302 	 * Now let the usual logic to set up the perf_event_attr defaults
303 	 * to kick in when we return and before perf_evsel__open() is called.
304 	 */
305 	attr.sample_period = 0;
306 new_event:
307 	evsel = perf_evsel__new(&attr);
308 	if (evsel == NULL)
309 		goto out;
310 
311 	/* use asprintf() because free(evsel) assumes name is allocated */
312 	if (asprintf(&evsel->name, "cycles%s%s%.*s",
313 		     (attr.precise_ip || attr.exclude_kernel) ? ":" : "",
314 		     attr.exclude_kernel ? "u" : "",
315 		     attr.precise_ip ? attr.precise_ip + 1 : 0, "ppp") < 0)
316 		goto error_free;
317 out:
318 	return evsel;
319 error_free:
320 	perf_evsel__delete(evsel);
321 	evsel = NULL;
322 	goto out;
323 }
324 
325 /*
326  * Returns pointer with encoded error via <linux/err.h> interface.
327  */
328 struct perf_evsel *perf_evsel__newtp_idx(const char *sys, const char *name, int idx)
329 {
330 	struct perf_evsel *evsel = zalloc(perf_evsel__object.size);
331 	int err = -ENOMEM;
332 
333 	if (evsel == NULL) {
334 		goto out_err;
335 	} else {
336 		struct perf_event_attr attr = {
337 			.type	       = PERF_TYPE_TRACEPOINT,
338 			.sample_type   = (PERF_SAMPLE_RAW | PERF_SAMPLE_TIME |
339 					  PERF_SAMPLE_CPU | PERF_SAMPLE_PERIOD),
340 		};
341 
342 		if (asprintf(&evsel->name, "%s:%s", sys, name) < 0)
343 			goto out_free;
344 
345 		evsel->tp_format = trace_event__tp_format(sys, name);
346 		if (IS_ERR(evsel->tp_format)) {
347 			err = PTR_ERR(evsel->tp_format);
348 			goto out_free;
349 		}
350 
351 		event_attr_init(&attr);
352 		attr.config = evsel->tp_format->id;
353 		attr.sample_period = 1;
354 		perf_evsel__init(evsel, &attr, idx);
355 	}
356 
357 	return evsel;
358 
359 out_free:
360 	zfree(&evsel->name);
361 	free(evsel);
362 out_err:
363 	return ERR_PTR(err);
364 }
365 
366 const char *perf_evsel__hw_names[PERF_COUNT_HW_MAX] = {
367 	"cycles",
368 	"instructions",
369 	"cache-references",
370 	"cache-misses",
371 	"branches",
372 	"branch-misses",
373 	"bus-cycles",
374 	"stalled-cycles-frontend",
375 	"stalled-cycles-backend",
376 	"ref-cycles",
377 };
378 
379 static const char *__perf_evsel__hw_name(u64 config)
380 {
381 	if (config < PERF_COUNT_HW_MAX && perf_evsel__hw_names[config])
382 		return perf_evsel__hw_names[config];
383 
384 	return "unknown-hardware";
385 }
386 
387 static int perf_evsel__add_modifiers(struct perf_evsel *evsel, char *bf, size_t size)
388 {
389 	int colon = 0, r = 0;
390 	struct perf_event_attr *attr = &evsel->attr;
391 	bool exclude_guest_default = false;
392 
393 #define MOD_PRINT(context, mod)	do {					\
394 		if (!attr->exclude_##context) {				\
395 			if (!colon) colon = ++r;			\
396 			r += scnprintf(bf + r, size - r, "%c", mod);	\
397 		} } while(0)
398 
399 	if (attr->exclude_kernel || attr->exclude_user || attr->exclude_hv) {
400 		MOD_PRINT(kernel, 'k');
401 		MOD_PRINT(user, 'u');
402 		MOD_PRINT(hv, 'h');
403 		exclude_guest_default = true;
404 	}
405 
406 	if (attr->precise_ip) {
407 		if (!colon)
408 			colon = ++r;
409 		r += scnprintf(bf + r, size - r, "%.*s", attr->precise_ip, "ppp");
410 		exclude_guest_default = true;
411 	}
412 
413 	if (attr->exclude_host || attr->exclude_guest == exclude_guest_default) {
414 		MOD_PRINT(host, 'H');
415 		MOD_PRINT(guest, 'G');
416 	}
417 #undef MOD_PRINT
418 	if (colon)
419 		bf[colon - 1] = ':';
420 	return r;
421 }
422 
423 static int perf_evsel__hw_name(struct perf_evsel *evsel, char *bf, size_t size)
424 {
425 	int r = scnprintf(bf, size, "%s", __perf_evsel__hw_name(evsel->attr.config));
426 	return r + perf_evsel__add_modifiers(evsel, bf + r, size - r);
427 }
428 
429 const char *perf_evsel__sw_names[PERF_COUNT_SW_MAX] = {
430 	"cpu-clock",
431 	"task-clock",
432 	"page-faults",
433 	"context-switches",
434 	"cpu-migrations",
435 	"minor-faults",
436 	"major-faults",
437 	"alignment-faults",
438 	"emulation-faults",
439 	"dummy",
440 };
441 
442 static const char *__perf_evsel__sw_name(u64 config)
443 {
444 	if (config < PERF_COUNT_SW_MAX && perf_evsel__sw_names[config])
445 		return perf_evsel__sw_names[config];
446 	return "unknown-software";
447 }
448 
449 static int perf_evsel__sw_name(struct perf_evsel *evsel, char *bf, size_t size)
450 {
451 	int r = scnprintf(bf, size, "%s", __perf_evsel__sw_name(evsel->attr.config));
452 	return r + perf_evsel__add_modifiers(evsel, bf + r, size - r);
453 }
454 
455 static int __perf_evsel__bp_name(char *bf, size_t size, u64 addr, u64 type)
456 {
457 	int r;
458 
459 	r = scnprintf(bf, size, "mem:0x%" PRIx64 ":", addr);
460 
461 	if (type & HW_BREAKPOINT_R)
462 		r += scnprintf(bf + r, size - r, "r");
463 
464 	if (type & HW_BREAKPOINT_W)
465 		r += scnprintf(bf + r, size - r, "w");
466 
467 	if (type & HW_BREAKPOINT_X)
468 		r += scnprintf(bf + r, size - r, "x");
469 
470 	return r;
471 }
472 
473 static int perf_evsel__bp_name(struct perf_evsel *evsel, char *bf, size_t size)
474 {
475 	struct perf_event_attr *attr = &evsel->attr;
476 	int r = __perf_evsel__bp_name(bf, size, attr->bp_addr, attr->bp_type);
477 	return r + perf_evsel__add_modifiers(evsel, bf + r, size - r);
478 }
479 
480 const char *perf_evsel__hw_cache[PERF_COUNT_HW_CACHE_MAX]
481 				[PERF_EVSEL__MAX_ALIASES] = {
482  { "L1-dcache",	"l1-d",		"l1d",		"L1-data",		},
483  { "L1-icache",	"l1-i",		"l1i",		"L1-instruction",	},
484  { "LLC",	"L2",							},
485  { "dTLB",	"d-tlb",	"Data-TLB",				},
486  { "iTLB",	"i-tlb",	"Instruction-TLB",			},
487  { "branch",	"branches",	"bpu",		"btb",		"bpc",	},
488  { "node",								},
489 };
490 
491 const char *perf_evsel__hw_cache_op[PERF_COUNT_HW_CACHE_OP_MAX]
492 				   [PERF_EVSEL__MAX_ALIASES] = {
493  { "load",	"loads",	"read",					},
494  { "store",	"stores",	"write",				},
495  { "prefetch",	"prefetches",	"speculative-read", "speculative-load",	},
496 };
497 
498 const char *perf_evsel__hw_cache_result[PERF_COUNT_HW_CACHE_RESULT_MAX]
499 				       [PERF_EVSEL__MAX_ALIASES] = {
500  { "refs",	"Reference",	"ops",		"access",		},
501  { "misses",	"miss",							},
502 };
503 
504 #define C(x)		PERF_COUNT_HW_CACHE_##x
505 #define CACHE_READ	(1 << C(OP_READ))
506 #define CACHE_WRITE	(1 << C(OP_WRITE))
507 #define CACHE_PREFETCH	(1 << C(OP_PREFETCH))
508 #define COP(x)		(1 << x)
509 
510 /*
511  * cache operartion stat
512  * L1I : Read and prefetch only
513  * ITLB and BPU : Read-only
514  */
515 static unsigned long perf_evsel__hw_cache_stat[C(MAX)] = {
516  [C(L1D)]	= (CACHE_READ | CACHE_WRITE | CACHE_PREFETCH),
517  [C(L1I)]	= (CACHE_READ | CACHE_PREFETCH),
518  [C(LL)]	= (CACHE_READ | CACHE_WRITE | CACHE_PREFETCH),
519  [C(DTLB)]	= (CACHE_READ | CACHE_WRITE | CACHE_PREFETCH),
520  [C(ITLB)]	= (CACHE_READ),
521  [C(BPU)]	= (CACHE_READ),
522  [C(NODE)]	= (CACHE_READ | CACHE_WRITE | CACHE_PREFETCH),
523 };
524 
525 bool perf_evsel__is_cache_op_valid(u8 type, u8 op)
526 {
527 	if (perf_evsel__hw_cache_stat[type] & COP(op))
528 		return true;	/* valid */
529 	else
530 		return false;	/* invalid */
531 }
532 
533 int __perf_evsel__hw_cache_type_op_res_name(u8 type, u8 op, u8 result,
534 					    char *bf, size_t size)
535 {
536 	if (result) {
537 		return scnprintf(bf, size, "%s-%s-%s", perf_evsel__hw_cache[type][0],
538 				 perf_evsel__hw_cache_op[op][0],
539 				 perf_evsel__hw_cache_result[result][0]);
540 	}
541 
542 	return scnprintf(bf, size, "%s-%s", perf_evsel__hw_cache[type][0],
543 			 perf_evsel__hw_cache_op[op][1]);
544 }
545 
546 static int __perf_evsel__hw_cache_name(u64 config, char *bf, size_t size)
547 {
548 	u8 op, result, type = (config >>  0) & 0xff;
549 	const char *err = "unknown-ext-hardware-cache-type";
550 
551 	if (type >= PERF_COUNT_HW_CACHE_MAX)
552 		goto out_err;
553 
554 	op = (config >>  8) & 0xff;
555 	err = "unknown-ext-hardware-cache-op";
556 	if (op >= PERF_COUNT_HW_CACHE_OP_MAX)
557 		goto out_err;
558 
559 	result = (config >> 16) & 0xff;
560 	err = "unknown-ext-hardware-cache-result";
561 	if (result >= PERF_COUNT_HW_CACHE_RESULT_MAX)
562 		goto out_err;
563 
564 	err = "invalid-cache";
565 	if (!perf_evsel__is_cache_op_valid(type, op))
566 		goto out_err;
567 
568 	return __perf_evsel__hw_cache_type_op_res_name(type, op, result, bf, size);
569 out_err:
570 	return scnprintf(bf, size, "%s", err);
571 }
572 
573 static int perf_evsel__hw_cache_name(struct perf_evsel *evsel, char *bf, size_t size)
574 {
575 	int ret = __perf_evsel__hw_cache_name(evsel->attr.config, bf, size);
576 	return ret + perf_evsel__add_modifiers(evsel, bf + ret, size - ret);
577 }
578 
579 static int perf_evsel__raw_name(struct perf_evsel *evsel, char *bf, size_t size)
580 {
581 	int ret = scnprintf(bf, size, "raw 0x%" PRIx64, evsel->attr.config);
582 	return ret + perf_evsel__add_modifiers(evsel, bf + ret, size - ret);
583 }
584 
585 const char *perf_evsel__name(struct perf_evsel *evsel)
586 {
587 	char bf[128];
588 
589 	if (evsel->name)
590 		return evsel->name;
591 
592 	switch (evsel->attr.type) {
593 	case PERF_TYPE_RAW:
594 		perf_evsel__raw_name(evsel, bf, sizeof(bf));
595 		break;
596 
597 	case PERF_TYPE_HARDWARE:
598 		perf_evsel__hw_name(evsel, bf, sizeof(bf));
599 		break;
600 
601 	case PERF_TYPE_HW_CACHE:
602 		perf_evsel__hw_cache_name(evsel, bf, sizeof(bf));
603 		break;
604 
605 	case PERF_TYPE_SOFTWARE:
606 		perf_evsel__sw_name(evsel, bf, sizeof(bf));
607 		break;
608 
609 	case PERF_TYPE_TRACEPOINT:
610 		scnprintf(bf, sizeof(bf), "%s", "unknown tracepoint");
611 		break;
612 
613 	case PERF_TYPE_BREAKPOINT:
614 		perf_evsel__bp_name(evsel, bf, sizeof(bf));
615 		break;
616 
617 	default:
618 		scnprintf(bf, sizeof(bf), "unknown attr type: %d",
619 			  evsel->attr.type);
620 		break;
621 	}
622 
623 	evsel->name = strdup(bf);
624 
625 	return evsel->name ?: "unknown";
626 }
627 
628 const char *perf_evsel__group_name(struct perf_evsel *evsel)
629 {
630 	return evsel->group_name ?: "anon group";
631 }
632 
633 int perf_evsel__group_desc(struct perf_evsel *evsel, char *buf, size_t size)
634 {
635 	int ret;
636 	struct perf_evsel *pos;
637 	const char *group_name = perf_evsel__group_name(evsel);
638 
639 	ret = scnprintf(buf, size, "%s", group_name);
640 
641 	ret += scnprintf(buf + ret, size - ret, " { %s",
642 			 perf_evsel__name(evsel));
643 
644 	for_each_group_member(pos, evsel)
645 		ret += scnprintf(buf + ret, size - ret, ", %s",
646 				 perf_evsel__name(pos));
647 
648 	ret += scnprintf(buf + ret, size - ret, " }");
649 
650 	return ret;
651 }
652 
653 void perf_evsel__config_callchain(struct perf_evsel *evsel,
654 				  struct record_opts *opts,
655 				  struct callchain_param *param)
656 {
657 	bool function = perf_evsel__is_function_event(evsel);
658 	struct perf_event_attr *attr = &evsel->attr;
659 
660 	perf_evsel__set_sample_bit(evsel, CALLCHAIN);
661 
662 	attr->sample_max_stack = param->max_stack;
663 
664 	if (param->record_mode == CALLCHAIN_LBR) {
665 		if (!opts->branch_stack) {
666 			if (attr->exclude_user) {
667 				pr_warning("LBR callstack option is only available "
668 					   "to get user callchain information. "
669 					   "Falling back to framepointers.\n");
670 			} else {
671 				perf_evsel__set_sample_bit(evsel, BRANCH_STACK);
672 				attr->branch_sample_type = PERF_SAMPLE_BRANCH_USER |
673 							PERF_SAMPLE_BRANCH_CALL_STACK |
674 							PERF_SAMPLE_BRANCH_NO_CYCLES |
675 							PERF_SAMPLE_BRANCH_NO_FLAGS;
676 			}
677 		} else
678 			 pr_warning("Cannot use LBR callstack with branch stack. "
679 				    "Falling back to framepointers.\n");
680 	}
681 
682 	if (param->record_mode == CALLCHAIN_DWARF) {
683 		if (!function) {
684 			perf_evsel__set_sample_bit(evsel, REGS_USER);
685 			perf_evsel__set_sample_bit(evsel, STACK_USER);
686 			attr->sample_regs_user |= PERF_REGS_MASK;
687 			attr->sample_stack_user = param->dump_size;
688 			attr->exclude_callchain_user = 1;
689 		} else {
690 			pr_info("Cannot use DWARF unwind for function trace event,"
691 				" falling back to framepointers.\n");
692 		}
693 	}
694 
695 	if (function) {
696 		pr_info("Disabling user space callchains for function trace event.\n");
697 		attr->exclude_callchain_user = 1;
698 	}
699 }
700 
701 static void
702 perf_evsel__reset_callgraph(struct perf_evsel *evsel,
703 			    struct callchain_param *param)
704 {
705 	struct perf_event_attr *attr = &evsel->attr;
706 
707 	perf_evsel__reset_sample_bit(evsel, CALLCHAIN);
708 	if (param->record_mode == CALLCHAIN_LBR) {
709 		perf_evsel__reset_sample_bit(evsel, BRANCH_STACK);
710 		attr->branch_sample_type &= ~(PERF_SAMPLE_BRANCH_USER |
711 					      PERF_SAMPLE_BRANCH_CALL_STACK);
712 	}
713 	if (param->record_mode == CALLCHAIN_DWARF) {
714 		perf_evsel__reset_sample_bit(evsel, REGS_USER);
715 		perf_evsel__reset_sample_bit(evsel, STACK_USER);
716 	}
717 }
718 
719 static void apply_config_terms(struct perf_evsel *evsel,
720 			       struct record_opts *opts)
721 {
722 	struct perf_evsel_config_term *term;
723 	struct list_head *config_terms = &evsel->config_terms;
724 	struct perf_event_attr *attr = &evsel->attr;
725 	struct callchain_param param;
726 	u32 dump_size = 0;
727 	int max_stack = 0;
728 	const char *callgraph_buf = NULL;
729 
730 	/* callgraph default */
731 	param.record_mode = callchain_param.record_mode;
732 
733 	list_for_each_entry(term, config_terms, list) {
734 		switch (term->type) {
735 		case PERF_EVSEL__CONFIG_TERM_PERIOD:
736 			if (!(term->weak && opts->user_interval != ULLONG_MAX)) {
737 				attr->sample_period = term->val.period;
738 				attr->freq = 0;
739 			}
740 			break;
741 		case PERF_EVSEL__CONFIG_TERM_FREQ:
742 			if (!(term->weak && opts->user_freq != UINT_MAX)) {
743 				attr->sample_freq = term->val.freq;
744 				attr->freq = 1;
745 			}
746 			break;
747 		case PERF_EVSEL__CONFIG_TERM_TIME:
748 			if (term->val.time)
749 				perf_evsel__set_sample_bit(evsel, TIME);
750 			else
751 				perf_evsel__reset_sample_bit(evsel, TIME);
752 			break;
753 		case PERF_EVSEL__CONFIG_TERM_CALLGRAPH:
754 			callgraph_buf = term->val.callgraph;
755 			break;
756 		case PERF_EVSEL__CONFIG_TERM_BRANCH:
757 			if (term->val.branch && strcmp(term->val.branch, "no")) {
758 				perf_evsel__set_sample_bit(evsel, BRANCH_STACK);
759 				parse_branch_str(term->val.branch,
760 						 &attr->branch_sample_type);
761 			} else
762 				perf_evsel__reset_sample_bit(evsel, BRANCH_STACK);
763 			break;
764 		case PERF_EVSEL__CONFIG_TERM_STACK_USER:
765 			dump_size = term->val.stack_user;
766 			break;
767 		case PERF_EVSEL__CONFIG_TERM_MAX_STACK:
768 			max_stack = term->val.max_stack;
769 			break;
770 		case PERF_EVSEL__CONFIG_TERM_INHERIT:
771 			/*
772 			 * attr->inherit should has already been set by
773 			 * perf_evsel__config. If user explicitly set
774 			 * inherit using config terms, override global
775 			 * opt->no_inherit setting.
776 			 */
777 			attr->inherit = term->val.inherit ? 1 : 0;
778 			break;
779 		case PERF_EVSEL__CONFIG_TERM_OVERWRITE:
780 			attr->write_backward = term->val.overwrite ? 1 : 0;
781 			break;
782 		default:
783 			break;
784 		}
785 	}
786 
787 	/* User explicitly set per-event callgraph, clear the old setting and reset. */
788 	if ((callgraph_buf != NULL) || (dump_size > 0) || max_stack) {
789 		if (max_stack) {
790 			param.max_stack = max_stack;
791 			if (callgraph_buf == NULL)
792 				callgraph_buf = "fp";
793 		}
794 
795 		/* parse callgraph parameters */
796 		if (callgraph_buf != NULL) {
797 			if (!strcmp(callgraph_buf, "no")) {
798 				param.enabled = false;
799 				param.record_mode = CALLCHAIN_NONE;
800 			} else {
801 				param.enabled = true;
802 				if (parse_callchain_record(callgraph_buf, &param)) {
803 					pr_err("per-event callgraph setting for %s failed. "
804 					       "Apply callgraph global setting for it\n",
805 					       evsel->name);
806 					return;
807 				}
808 			}
809 		}
810 		if (dump_size > 0) {
811 			dump_size = round_up(dump_size, sizeof(u64));
812 			param.dump_size = dump_size;
813 		}
814 
815 		/* If global callgraph set, clear it */
816 		if (callchain_param.enabled)
817 			perf_evsel__reset_callgraph(evsel, &callchain_param);
818 
819 		/* set perf-event callgraph */
820 		if (param.enabled)
821 			perf_evsel__config_callchain(evsel, opts, &param);
822 	}
823 }
824 
825 /*
826  * The enable_on_exec/disabled value strategy:
827  *
828  *  1) For any type of traced program:
829  *    - all independent events and group leaders are disabled
830  *    - all group members are enabled
831  *
832  *     Group members are ruled by group leaders. They need to
833  *     be enabled, because the group scheduling relies on that.
834  *
835  *  2) For traced programs executed by perf:
836  *     - all independent events and group leaders have
837  *       enable_on_exec set
838  *     - we don't specifically enable or disable any event during
839  *       the record command
840  *
841  *     Independent events and group leaders are initially disabled
842  *     and get enabled by exec. Group members are ruled by group
843  *     leaders as stated in 1).
844  *
845  *  3) For traced programs attached by perf (pid/tid):
846  *     - we specifically enable or disable all events during
847  *       the record command
848  *
849  *     When attaching events to already running traced we
850  *     enable/disable events specifically, as there's no
851  *     initial traced exec call.
852  */
853 void perf_evsel__config(struct perf_evsel *evsel, struct record_opts *opts,
854 			struct callchain_param *callchain)
855 {
856 	struct perf_evsel *leader = evsel->leader;
857 	struct perf_event_attr *attr = &evsel->attr;
858 	int track = evsel->tracking;
859 	bool per_cpu = opts->target.default_per_cpu && !opts->target.per_thread;
860 
861 	attr->sample_id_all = perf_missing_features.sample_id_all ? 0 : 1;
862 	attr->inherit	    = !opts->no_inherit;
863 	attr->write_backward = opts->overwrite ? 1 : 0;
864 
865 	perf_evsel__set_sample_bit(evsel, IP);
866 	perf_evsel__set_sample_bit(evsel, TID);
867 
868 	if (evsel->sample_read) {
869 		perf_evsel__set_sample_bit(evsel, READ);
870 
871 		/*
872 		 * We need ID even in case of single event, because
873 		 * PERF_SAMPLE_READ process ID specific data.
874 		 */
875 		perf_evsel__set_sample_id(evsel, false);
876 
877 		/*
878 		 * Apply group format only if we belong to group
879 		 * with more than one members.
880 		 */
881 		if (leader->nr_members > 1) {
882 			attr->read_format |= PERF_FORMAT_GROUP;
883 			attr->inherit = 0;
884 		}
885 	}
886 
887 	/*
888 	 * We default some events to have a default interval. But keep
889 	 * it a weak assumption overridable by the user.
890 	 */
891 	if (!attr->sample_period || (opts->user_freq != UINT_MAX ||
892 				     opts->user_interval != ULLONG_MAX)) {
893 		if (opts->freq) {
894 			perf_evsel__set_sample_bit(evsel, PERIOD);
895 			attr->freq		= 1;
896 			attr->sample_freq	= opts->freq;
897 		} else {
898 			attr->sample_period = opts->default_interval;
899 		}
900 	}
901 
902 	/*
903 	 * Disable sampling for all group members other
904 	 * than leader in case leader 'leads' the sampling.
905 	 */
906 	if ((leader != evsel) && leader->sample_read) {
907 		attr->sample_freq   = 0;
908 		attr->sample_period = 0;
909 	}
910 
911 	if (opts->no_samples)
912 		attr->sample_freq = 0;
913 
914 	if (opts->inherit_stat) {
915 		evsel->attr.read_format |=
916 			PERF_FORMAT_TOTAL_TIME_ENABLED |
917 			PERF_FORMAT_TOTAL_TIME_RUNNING |
918 			PERF_FORMAT_ID;
919 		attr->inherit_stat = 1;
920 	}
921 
922 	if (opts->sample_address) {
923 		perf_evsel__set_sample_bit(evsel, ADDR);
924 		attr->mmap_data = track;
925 	}
926 
927 	/*
928 	 * We don't allow user space callchains for  function trace
929 	 * event, due to issues with page faults while tracing page
930 	 * fault handler and its overall trickiness nature.
931 	 */
932 	if (perf_evsel__is_function_event(evsel))
933 		evsel->attr.exclude_callchain_user = 1;
934 
935 	if (callchain && callchain->enabled && !evsel->no_aux_samples)
936 		perf_evsel__config_callchain(evsel, opts, callchain);
937 
938 	if (opts->sample_intr_regs) {
939 		attr->sample_regs_intr = opts->sample_intr_regs;
940 		perf_evsel__set_sample_bit(evsel, REGS_INTR);
941 	}
942 
943 	if (opts->sample_user_regs) {
944 		attr->sample_regs_user |= opts->sample_user_regs;
945 		perf_evsel__set_sample_bit(evsel, REGS_USER);
946 	}
947 
948 	if (target__has_cpu(&opts->target) || opts->sample_cpu)
949 		perf_evsel__set_sample_bit(evsel, CPU);
950 
951 	if (opts->period)
952 		perf_evsel__set_sample_bit(evsel, PERIOD);
953 
954 	/*
955 	 * When the user explicitly disabled time don't force it here.
956 	 */
957 	if (opts->sample_time &&
958 	    (!perf_missing_features.sample_id_all &&
959 	    (!opts->no_inherit || target__has_cpu(&opts->target) || per_cpu ||
960 	     opts->sample_time_set)))
961 		perf_evsel__set_sample_bit(evsel, TIME);
962 
963 	if (opts->raw_samples && !evsel->no_aux_samples) {
964 		perf_evsel__set_sample_bit(evsel, TIME);
965 		perf_evsel__set_sample_bit(evsel, RAW);
966 		perf_evsel__set_sample_bit(evsel, CPU);
967 	}
968 
969 	if (opts->sample_address)
970 		perf_evsel__set_sample_bit(evsel, DATA_SRC);
971 
972 	if (opts->sample_phys_addr)
973 		perf_evsel__set_sample_bit(evsel, PHYS_ADDR);
974 
975 	if (opts->no_buffering) {
976 		attr->watermark = 0;
977 		attr->wakeup_events = 1;
978 	}
979 	if (opts->branch_stack && !evsel->no_aux_samples) {
980 		perf_evsel__set_sample_bit(evsel, BRANCH_STACK);
981 		attr->branch_sample_type = opts->branch_stack;
982 	}
983 
984 	if (opts->sample_weight)
985 		perf_evsel__set_sample_bit(evsel, WEIGHT);
986 
987 	attr->task  = track;
988 	attr->mmap  = track;
989 	attr->mmap2 = track && !perf_missing_features.mmap2;
990 	attr->comm  = track;
991 
992 	if (opts->record_namespaces)
993 		attr->namespaces  = track;
994 
995 	if (opts->record_switch_events)
996 		attr->context_switch = track;
997 
998 	if (opts->sample_transaction)
999 		perf_evsel__set_sample_bit(evsel, TRANSACTION);
1000 
1001 	if (opts->running_time) {
1002 		evsel->attr.read_format |=
1003 			PERF_FORMAT_TOTAL_TIME_ENABLED |
1004 			PERF_FORMAT_TOTAL_TIME_RUNNING;
1005 	}
1006 
1007 	/*
1008 	 * XXX see the function comment above
1009 	 *
1010 	 * Disabling only independent events or group leaders,
1011 	 * keeping group members enabled.
1012 	 */
1013 	if (perf_evsel__is_group_leader(evsel))
1014 		attr->disabled = 1;
1015 
1016 	/*
1017 	 * Setting enable_on_exec for independent events and
1018 	 * group leaders for traced executed by perf.
1019 	 */
1020 	if (target__none(&opts->target) && perf_evsel__is_group_leader(evsel) &&
1021 		!opts->initial_delay)
1022 		attr->enable_on_exec = 1;
1023 
1024 	if (evsel->immediate) {
1025 		attr->disabled = 0;
1026 		attr->enable_on_exec = 0;
1027 	}
1028 
1029 	clockid = opts->clockid;
1030 	if (opts->use_clockid) {
1031 		attr->use_clockid = 1;
1032 		attr->clockid = opts->clockid;
1033 	}
1034 
1035 	if (evsel->precise_max)
1036 		perf_event_attr__set_max_precise_ip(attr);
1037 
1038 	if (opts->all_user) {
1039 		attr->exclude_kernel = 1;
1040 		attr->exclude_user   = 0;
1041 	}
1042 
1043 	if (opts->all_kernel) {
1044 		attr->exclude_kernel = 0;
1045 		attr->exclude_user   = 1;
1046 	}
1047 
1048 	/*
1049 	 * Apply event specific term settings,
1050 	 * it overloads any global configuration.
1051 	 */
1052 	apply_config_terms(evsel, opts);
1053 
1054 	evsel->ignore_missing_thread = opts->ignore_missing_thread;
1055 }
1056 
1057 static int perf_evsel__alloc_fd(struct perf_evsel *evsel, int ncpus, int nthreads)
1058 {
1059 	if (evsel->system_wide)
1060 		nthreads = 1;
1061 
1062 	evsel->fd = xyarray__new(ncpus, nthreads, sizeof(int));
1063 
1064 	if (evsel->fd) {
1065 		int cpu, thread;
1066 		for (cpu = 0; cpu < ncpus; cpu++) {
1067 			for (thread = 0; thread < nthreads; thread++) {
1068 				FD(evsel, cpu, thread) = -1;
1069 			}
1070 		}
1071 	}
1072 
1073 	return evsel->fd != NULL ? 0 : -ENOMEM;
1074 }
1075 
1076 static int perf_evsel__run_ioctl(struct perf_evsel *evsel,
1077 			  int ioc,  void *arg)
1078 {
1079 	int cpu, thread;
1080 
1081 	for (cpu = 0; cpu < xyarray__max_x(evsel->fd); cpu++) {
1082 		for (thread = 0; thread < xyarray__max_y(evsel->fd); thread++) {
1083 			int fd = FD(evsel, cpu, thread),
1084 			    err = ioctl(fd, ioc, arg);
1085 
1086 			if (err)
1087 				return err;
1088 		}
1089 	}
1090 
1091 	return 0;
1092 }
1093 
1094 int perf_evsel__apply_filter(struct perf_evsel *evsel, const char *filter)
1095 {
1096 	return perf_evsel__run_ioctl(evsel,
1097 				     PERF_EVENT_IOC_SET_FILTER,
1098 				     (void *)filter);
1099 }
1100 
1101 int perf_evsel__set_filter(struct perf_evsel *evsel, const char *filter)
1102 {
1103 	char *new_filter = strdup(filter);
1104 
1105 	if (new_filter != NULL) {
1106 		free(evsel->filter);
1107 		evsel->filter = new_filter;
1108 		return 0;
1109 	}
1110 
1111 	return -1;
1112 }
1113 
1114 static int perf_evsel__append_filter(struct perf_evsel *evsel,
1115 				     const char *fmt, const char *filter)
1116 {
1117 	char *new_filter;
1118 
1119 	if (evsel->filter == NULL)
1120 		return perf_evsel__set_filter(evsel, filter);
1121 
1122 	if (asprintf(&new_filter, fmt, evsel->filter, filter) > 0) {
1123 		free(evsel->filter);
1124 		evsel->filter = new_filter;
1125 		return 0;
1126 	}
1127 
1128 	return -1;
1129 }
1130 
1131 int perf_evsel__append_tp_filter(struct perf_evsel *evsel, const char *filter)
1132 {
1133 	return perf_evsel__append_filter(evsel, "(%s) && (%s)", filter);
1134 }
1135 
1136 int perf_evsel__append_addr_filter(struct perf_evsel *evsel, const char *filter)
1137 {
1138 	return perf_evsel__append_filter(evsel, "%s,%s", filter);
1139 }
1140 
1141 int perf_evsel__enable(struct perf_evsel *evsel)
1142 {
1143 	return perf_evsel__run_ioctl(evsel,
1144 				     PERF_EVENT_IOC_ENABLE,
1145 				     0);
1146 }
1147 
1148 int perf_evsel__disable(struct perf_evsel *evsel)
1149 {
1150 	return perf_evsel__run_ioctl(evsel,
1151 				     PERF_EVENT_IOC_DISABLE,
1152 				     0);
1153 }
1154 
1155 int perf_evsel__alloc_id(struct perf_evsel *evsel, int ncpus, int nthreads)
1156 {
1157 	if (ncpus == 0 || nthreads == 0)
1158 		return 0;
1159 
1160 	if (evsel->system_wide)
1161 		nthreads = 1;
1162 
1163 	evsel->sample_id = xyarray__new(ncpus, nthreads, sizeof(struct perf_sample_id));
1164 	if (evsel->sample_id == NULL)
1165 		return -ENOMEM;
1166 
1167 	evsel->id = zalloc(ncpus * nthreads * sizeof(u64));
1168 	if (evsel->id == NULL) {
1169 		xyarray__delete(evsel->sample_id);
1170 		evsel->sample_id = NULL;
1171 		return -ENOMEM;
1172 	}
1173 
1174 	return 0;
1175 }
1176 
1177 static void perf_evsel__free_fd(struct perf_evsel *evsel)
1178 {
1179 	xyarray__delete(evsel->fd);
1180 	evsel->fd = NULL;
1181 }
1182 
1183 static void perf_evsel__free_id(struct perf_evsel *evsel)
1184 {
1185 	xyarray__delete(evsel->sample_id);
1186 	evsel->sample_id = NULL;
1187 	zfree(&evsel->id);
1188 }
1189 
1190 static void perf_evsel__free_config_terms(struct perf_evsel *evsel)
1191 {
1192 	struct perf_evsel_config_term *term, *h;
1193 
1194 	list_for_each_entry_safe(term, h, &evsel->config_terms, list) {
1195 		list_del(&term->list);
1196 		free(term);
1197 	}
1198 }
1199 
1200 void perf_evsel__close_fd(struct perf_evsel *evsel)
1201 {
1202 	int cpu, thread;
1203 
1204 	for (cpu = 0; cpu < xyarray__max_x(evsel->fd); cpu++)
1205 		for (thread = 0; thread < xyarray__max_y(evsel->fd); ++thread) {
1206 			close(FD(evsel, cpu, thread));
1207 			FD(evsel, cpu, thread) = -1;
1208 		}
1209 }
1210 
1211 void perf_evsel__exit(struct perf_evsel *evsel)
1212 {
1213 	assert(list_empty(&evsel->node));
1214 	assert(evsel->evlist == NULL);
1215 	perf_evsel__free_fd(evsel);
1216 	perf_evsel__free_id(evsel);
1217 	perf_evsel__free_config_terms(evsel);
1218 	close_cgroup(evsel->cgrp);
1219 	cpu_map__put(evsel->cpus);
1220 	cpu_map__put(evsel->own_cpus);
1221 	thread_map__put(evsel->threads);
1222 	zfree(&evsel->group_name);
1223 	zfree(&evsel->name);
1224 	perf_evsel__object.fini(evsel);
1225 }
1226 
1227 void perf_evsel__delete(struct perf_evsel *evsel)
1228 {
1229 	perf_evsel__exit(evsel);
1230 	free(evsel);
1231 }
1232 
1233 void perf_evsel__compute_deltas(struct perf_evsel *evsel, int cpu, int thread,
1234 				struct perf_counts_values *count)
1235 {
1236 	struct perf_counts_values tmp;
1237 
1238 	if (!evsel->prev_raw_counts)
1239 		return;
1240 
1241 	if (cpu == -1) {
1242 		tmp = evsel->prev_raw_counts->aggr;
1243 		evsel->prev_raw_counts->aggr = *count;
1244 	} else {
1245 		tmp = *perf_counts(evsel->prev_raw_counts, cpu, thread);
1246 		*perf_counts(evsel->prev_raw_counts, cpu, thread) = *count;
1247 	}
1248 
1249 	count->val = count->val - tmp.val;
1250 	count->ena = count->ena - tmp.ena;
1251 	count->run = count->run - tmp.run;
1252 }
1253 
1254 void perf_counts_values__scale(struct perf_counts_values *count,
1255 			       bool scale, s8 *pscaled)
1256 {
1257 	s8 scaled = 0;
1258 
1259 	if (scale) {
1260 		if (count->run == 0) {
1261 			scaled = -1;
1262 			count->val = 0;
1263 		} else if (count->run < count->ena) {
1264 			scaled = 1;
1265 			count->val = (u64)((double) count->val * count->ena / count->run + 0.5);
1266 		}
1267 	} else
1268 		count->ena = count->run = 0;
1269 
1270 	if (pscaled)
1271 		*pscaled = scaled;
1272 }
1273 
1274 static int perf_evsel__read_size(struct perf_evsel *evsel)
1275 {
1276 	u64 read_format = evsel->attr.read_format;
1277 	int entry = sizeof(u64); /* value */
1278 	int size = 0;
1279 	int nr = 1;
1280 
1281 	if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED)
1282 		size += sizeof(u64);
1283 
1284 	if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING)
1285 		size += sizeof(u64);
1286 
1287 	if (read_format & PERF_FORMAT_ID)
1288 		entry += sizeof(u64);
1289 
1290 	if (read_format & PERF_FORMAT_GROUP) {
1291 		nr = evsel->nr_members;
1292 		size += sizeof(u64);
1293 	}
1294 
1295 	size += entry * nr;
1296 	return size;
1297 }
1298 
1299 int perf_evsel__read(struct perf_evsel *evsel, int cpu, int thread,
1300 		     struct perf_counts_values *count)
1301 {
1302 	size_t size = perf_evsel__read_size(evsel);
1303 
1304 	memset(count, 0, sizeof(*count));
1305 
1306 	if (FD(evsel, cpu, thread) < 0)
1307 		return -EINVAL;
1308 
1309 	if (readn(FD(evsel, cpu, thread), count->values, size) <= 0)
1310 		return -errno;
1311 
1312 	return 0;
1313 }
1314 
1315 static int
1316 perf_evsel__read_one(struct perf_evsel *evsel, int cpu, int thread)
1317 {
1318 	struct perf_counts_values *count = perf_counts(evsel->counts, cpu, thread);
1319 
1320 	return perf_evsel__read(evsel, cpu, thread, count);
1321 }
1322 
1323 static void
1324 perf_evsel__set_count(struct perf_evsel *counter, int cpu, int thread,
1325 		      u64 val, u64 ena, u64 run)
1326 {
1327 	struct perf_counts_values *count;
1328 
1329 	count = perf_counts(counter->counts, cpu, thread);
1330 
1331 	count->val    = val;
1332 	count->ena    = ena;
1333 	count->run    = run;
1334 	count->loaded = true;
1335 }
1336 
1337 static int
1338 perf_evsel__process_group_data(struct perf_evsel *leader,
1339 			       int cpu, int thread, u64 *data)
1340 {
1341 	u64 read_format = leader->attr.read_format;
1342 	struct sample_read_value *v;
1343 	u64 nr, ena = 0, run = 0, i;
1344 
1345 	nr = *data++;
1346 
1347 	if (nr != (u64) leader->nr_members)
1348 		return -EINVAL;
1349 
1350 	if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED)
1351 		ena = *data++;
1352 
1353 	if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING)
1354 		run = *data++;
1355 
1356 	v = (struct sample_read_value *) data;
1357 
1358 	perf_evsel__set_count(leader, cpu, thread,
1359 			      v[0].value, ena, run);
1360 
1361 	for (i = 1; i < nr; i++) {
1362 		struct perf_evsel *counter;
1363 
1364 		counter = perf_evlist__id2evsel(leader->evlist, v[i].id);
1365 		if (!counter)
1366 			return -EINVAL;
1367 
1368 		perf_evsel__set_count(counter, cpu, thread,
1369 				      v[i].value, ena, run);
1370 	}
1371 
1372 	return 0;
1373 }
1374 
1375 static int
1376 perf_evsel__read_group(struct perf_evsel *leader, int cpu, int thread)
1377 {
1378 	struct perf_stat_evsel *ps = leader->stats;
1379 	u64 read_format = leader->attr.read_format;
1380 	int size = perf_evsel__read_size(leader);
1381 	u64 *data = ps->group_data;
1382 
1383 	if (!(read_format & PERF_FORMAT_ID))
1384 		return -EINVAL;
1385 
1386 	if (!perf_evsel__is_group_leader(leader))
1387 		return -EINVAL;
1388 
1389 	if (!data) {
1390 		data = zalloc(size);
1391 		if (!data)
1392 			return -ENOMEM;
1393 
1394 		ps->group_data = data;
1395 	}
1396 
1397 	if (FD(leader, cpu, thread) < 0)
1398 		return -EINVAL;
1399 
1400 	if (readn(FD(leader, cpu, thread), data, size) <= 0)
1401 		return -errno;
1402 
1403 	return perf_evsel__process_group_data(leader, cpu, thread, data);
1404 }
1405 
1406 int perf_evsel__read_counter(struct perf_evsel *evsel, int cpu, int thread)
1407 {
1408 	u64 read_format = evsel->attr.read_format;
1409 
1410 	if (read_format & PERF_FORMAT_GROUP)
1411 		return perf_evsel__read_group(evsel, cpu, thread);
1412 	else
1413 		return perf_evsel__read_one(evsel, cpu, thread);
1414 }
1415 
1416 int __perf_evsel__read_on_cpu(struct perf_evsel *evsel,
1417 			      int cpu, int thread, bool scale)
1418 {
1419 	struct perf_counts_values count;
1420 	size_t nv = scale ? 3 : 1;
1421 
1422 	if (FD(evsel, cpu, thread) < 0)
1423 		return -EINVAL;
1424 
1425 	if (evsel->counts == NULL && perf_evsel__alloc_counts(evsel, cpu + 1, thread + 1) < 0)
1426 		return -ENOMEM;
1427 
1428 	if (readn(FD(evsel, cpu, thread), &count, nv * sizeof(u64)) <= 0)
1429 		return -errno;
1430 
1431 	perf_evsel__compute_deltas(evsel, cpu, thread, &count);
1432 	perf_counts_values__scale(&count, scale, NULL);
1433 	*perf_counts(evsel->counts, cpu, thread) = count;
1434 	return 0;
1435 }
1436 
1437 static int get_group_fd(struct perf_evsel *evsel, int cpu, int thread)
1438 {
1439 	struct perf_evsel *leader = evsel->leader;
1440 	int fd;
1441 
1442 	if (perf_evsel__is_group_leader(evsel))
1443 		return -1;
1444 
1445 	/*
1446 	 * Leader must be already processed/open,
1447 	 * if not it's a bug.
1448 	 */
1449 	BUG_ON(!leader->fd);
1450 
1451 	fd = FD(leader, cpu, thread);
1452 	BUG_ON(fd == -1);
1453 
1454 	return fd;
1455 }
1456 
1457 struct bit_names {
1458 	int bit;
1459 	const char *name;
1460 };
1461 
1462 static void __p_bits(char *buf, size_t size, u64 value, struct bit_names *bits)
1463 {
1464 	bool first_bit = true;
1465 	int i = 0;
1466 
1467 	do {
1468 		if (value & bits[i].bit) {
1469 			buf += scnprintf(buf, size, "%s%s", first_bit ? "" : "|", bits[i].name);
1470 			first_bit = false;
1471 		}
1472 	} while (bits[++i].name != NULL);
1473 }
1474 
1475 static void __p_sample_type(char *buf, size_t size, u64 value)
1476 {
1477 #define bit_name(n) { PERF_SAMPLE_##n, #n }
1478 	struct bit_names bits[] = {
1479 		bit_name(IP), bit_name(TID), bit_name(TIME), bit_name(ADDR),
1480 		bit_name(READ), bit_name(CALLCHAIN), bit_name(ID), bit_name(CPU),
1481 		bit_name(PERIOD), bit_name(STREAM_ID), bit_name(RAW),
1482 		bit_name(BRANCH_STACK), bit_name(REGS_USER), bit_name(STACK_USER),
1483 		bit_name(IDENTIFIER), bit_name(REGS_INTR), bit_name(DATA_SRC),
1484 		bit_name(WEIGHT), bit_name(PHYS_ADDR),
1485 		{ .name = NULL, }
1486 	};
1487 #undef bit_name
1488 	__p_bits(buf, size, value, bits);
1489 }
1490 
1491 static void __p_branch_sample_type(char *buf, size_t size, u64 value)
1492 {
1493 #define bit_name(n) { PERF_SAMPLE_BRANCH_##n, #n }
1494 	struct bit_names bits[] = {
1495 		bit_name(USER), bit_name(KERNEL), bit_name(HV), bit_name(ANY),
1496 		bit_name(ANY_CALL), bit_name(ANY_RETURN), bit_name(IND_CALL),
1497 		bit_name(ABORT_TX), bit_name(IN_TX), bit_name(NO_TX),
1498 		bit_name(COND), bit_name(CALL_STACK), bit_name(IND_JUMP),
1499 		bit_name(CALL), bit_name(NO_FLAGS), bit_name(NO_CYCLES),
1500 		{ .name = NULL, }
1501 	};
1502 #undef bit_name
1503 	__p_bits(buf, size, value, bits);
1504 }
1505 
1506 static void __p_read_format(char *buf, size_t size, u64 value)
1507 {
1508 #define bit_name(n) { PERF_FORMAT_##n, #n }
1509 	struct bit_names bits[] = {
1510 		bit_name(TOTAL_TIME_ENABLED), bit_name(TOTAL_TIME_RUNNING),
1511 		bit_name(ID), bit_name(GROUP),
1512 		{ .name = NULL, }
1513 	};
1514 #undef bit_name
1515 	__p_bits(buf, size, value, bits);
1516 }
1517 
1518 #define BUF_SIZE		1024
1519 
1520 #define p_hex(val)		snprintf(buf, BUF_SIZE, "%#"PRIx64, (uint64_t)(val))
1521 #define p_unsigned(val)		snprintf(buf, BUF_SIZE, "%"PRIu64, (uint64_t)(val))
1522 #define p_signed(val)		snprintf(buf, BUF_SIZE, "%"PRId64, (int64_t)(val))
1523 #define p_sample_type(val)	__p_sample_type(buf, BUF_SIZE, val)
1524 #define p_branch_sample_type(val) __p_branch_sample_type(buf, BUF_SIZE, val)
1525 #define p_read_format(val)	__p_read_format(buf, BUF_SIZE, val)
1526 
1527 #define PRINT_ATTRn(_n, _f, _p)				\
1528 do {							\
1529 	if (attr->_f) {					\
1530 		_p(attr->_f);				\
1531 		ret += attr__fprintf(fp, _n, buf, priv);\
1532 	}						\
1533 } while (0)
1534 
1535 #define PRINT_ATTRf(_f, _p)	PRINT_ATTRn(#_f, _f, _p)
1536 
1537 int perf_event_attr__fprintf(FILE *fp, struct perf_event_attr *attr,
1538 			     attr__fprintf_f attr__fprintf, void *priv)
1539 {
1540 	char buf[BUF_SIZE];
1541 	int ret = 0;
1542 
1543 	PRINT_ATTRf(type, p_unsigned);
1544 	PRINT_ATTRf(size, p_unsigned);
1545 	PRINT_ATTRf(config, p_hex);
1546 	PRINT_ATTRn("{ sample_period, sample_freq }", sample_period, p_unsigned);
1547 	PRINT_ATTRf(sample_type, p_sample_type);
1548 	PRINT_ATTRf(read_format, p_read_format);
1549 
1550 	PRINT_ATTRf(disabled, p_unsigned);
1551 	PRINT_ATTRf(inherit, p_unsigned);
1552 	PRINT_ATTRf(pinned, p_unsigned);
1553 	PRINT_ATTRf(exclusive, p_unsigned);
1554 	PRINT_ATTRf(exclude_user, p_unsigned);
1555 	PRINT_ATTRf(exclude_kernel, p_unsigned);
1556 	PRINT_ATTRf(exclude_hv, p_unsigned);
1557 	PRINT_ATTRf(exclude_idle, p_unsigned);
1558 	PRINT_ATTRf(mmap, p_unsigned);
1559 	PRINT_ATTRf(comm, p_unsigned);
1560 	PRINT_ATTRf(freq, p_unsigned);
1561 	PRINT_ATTRf(inherit_stat, p_unsigned);
1562 	PRINT_ATTRf(enable_on_exec, p_unsigned);
1563 	PRINT_ATTRf(task, p_unsigned);
1564 	PRINT_ATTRf(watermark, p_unsigned);
1565 	PRINT_ATTRf(precise_ip, p_unsigned);
1566 	PRINT_ATTRf(mmap_data, p_unsigned);
1567 	PRINT_ATTRf(sample_id_all, p_unsigned);
1568 	PRINT_ATTRf(exclude_host, p_unsigned);
1569 	PRINT_ATTRf(exclude_guest, p_unsigned);
1570 	PRINT_ATTRf(exclude_callchain_kernel, p_unsigned);
1571 	PRINT_ATTRf(exclude_callchain_user, p_unsigned);
1572 	PRINT_ATTRf(mmap2, p_unsigned);
1573 	PRINT_ATTRf(comm_exec, p_unsigned);
1574 	PRINT_ATTRf(use_clockid, p_unsigned);
1575 	PRINT_ATTRf(context_switch, p_unsigned);
1576 	PRINT_ATTRf(write_backward, p_unsigned);
1577 
1578 	PRINT_ATTRn("{ wakeup_events, wakeup_watermark }", wakeup_events, p_unsigned);
1579 	PRINT_ATTRf(bp_type, p_unsigned);
1580 	PRINT_ATTRn("{ bp_addr, config1 }", bp_addr, p_hex);
1581 	PRINT_ATTRn("{ bp_len, config2 }", bp_len, p_hex);
1582 	PRINT_ATTRf(branch_sample_type, p_branch_sample_type);
1583 	PRINT_ATTRf(sample_regs_user, p_hex);
1584 	PRINT_ATTRf(sample_stack_user, p_unsigned);
1585 	PRINT_ATTRf(clockid, p_signed);
1586 	PRINT_ATTRf(sample_regs_intr, p_hex);
1587 	PRINT_ATTRf(aux_watermark, p_unsigned);
1588 	PRINT_ATTRf(sample_max_stack, p_unsigned);
1589 
1590 	return ret;
1591 }
1592 
1593 static int __open_attr__fprintf(FILE *fp, const char *name, const char *val,
1594 				void *priv __maybe_unused)
1595 {
1596 	return fprintf(fp, "  %-32s %s\n", name, val);
1597 }
1598 
1599 static bool ignore_missing_thread(struct perf_evsel *evsel,
1600 				  struct thread_map *threads,
1601 				  int thread, int err)
1602 {
1603 	if (!evsel->ignore_missing_thread)
1604 		return false;
1605 
1606 	/* The system wide setup does not work with threads. */
1607 	if (evsel->system_wide)
1608 		return false;
1609 
1610 	/* The -ESRCH is perf event syscall errno for pid's not found. */
1611 	if (err != -ESRCH)
1612 		return false;
1613 
1614 	/* If there's only one thread, let it fail. */
1615 	if (threads->nr == 1)
1616 		return false;
1617 
1618 	if (thread_map__remove(threads, thread))
1619 		return false;
1620 
1621 	pr_warning("WARNING: Ignored open failure for pid %d\n",
1622 		   thread_map__pid(threads, thread));
1623 	return true;
1624 }
1625 
1626 int perf_evsel__open(struct perf_evsel *evsel, struct cpu_map *cpus,
1627 		     struct thread_map *threads)
1628 {
1629 	int cpu, thread, nthreads;
1630 	unsigned long flags = PERF_FLAG_FD_CLOEXEC;
1631 	int pid = -1, err;
1632 	enum { NO_CHANGE, SET_TO_MAX, INCREASED_MAX } set_rlimit = NO_CHANGE;
1633 
1634 	if (perf_missing_features.write_backward && evsel->attr.write_backward)
1635 		return -EINVAL;
1636 
1637 	if (cpus == NULL) {
1638 		static struct cpu_map *empty_cpu_map;
1639 
1640 		if (empty_cpu_map == NULL) {
1641 			empty_cpu_map = cpu_map__dummy_new();
1642 			if (empty_cpu_map == NULL)
1643 				return -ENOMEM;
1644 		}
1645 
1646 		cpus = empty_cpu_map;
1647 	}
1648 
1649 	if (threads == NULL) {
1650 		static struct thread_map *empty_thread_map;
1651 
1652 		if (empty_thread_map == NULL) {
1653 			empty_thread_map = thread_map__new_by_tid(-1);
1654 			if (empty_thread_map == NULL)
1655 				return -ENOMEM;
1656 		}
1657 
1658 		threads = empty_thread_map;
1659 	}
1660 
1661 	if (evsel->system_wide)
1662 		nthreads = 1;
1663 	else
1664 		nthreads = threads->nr;
1665 
1666 	if (evsel->fd == NULL &&
1667 	    perf_evsel__alloc_fd(evsel, cpus->nr, nthreads) < 0)
1668 		return -ENOMEM;
1669 
1670 	if (evsel->cgrp) {
1671 		flags |= PERF_FLAG_PID_CGROUP;
1672 		pid = evsel->cgrp->fd;
1673 	}
1674 
1675 fallback_missing_features:
1676 	if (perf_missing_features.clockid_wrong)
1677 		evsel->attr.clockid = CLOCK_MONOTONIC; /* should always work */
1678 	if (perf_missing_features.clockid) {
1679 		evsel->attr.use_clockid = 0;
1680 		evsel->attr.clockid = 0;
1681 	}
1682 	if (perf_missing_features.cloexec)
1683 		flags &= ~(unsigned long)PERF_FLAG_FD_CLOEXEC;
1684 	if (perf_missing_features.mmap2)
1685 		evsel->attr.mmap2 = 0;
1686 	if (perf_missing_features.exclude_guest)
1687 		evsel->attr.exclude_guest = evsel->attr.exclude_host = 0;
1688 	if (perf_missing_features.lbr_flags)
1689 		evsel->attr.branch_sample_type &= ~(PERF_SAMPLE_BRANCH_NO_FLAGS |
1690 				     PERF_SAMPLE_BRANCH_NO_CYCLES);
1691 	if (perf_missing_features.group_read && evsel->attr.inherit)
1692 		evsel->attr.read_format &= ~(PERF_FORMAT_GROUP|PERF_FORMAT_ID);
1693 retry_sample_id:
1694 	if (perf_missing_features.sample_id_all)
1695 		evsel->attr.sample_id_all = 0;
1696 
1697 	if (verbose >= 2) {
1698 		fprintf(stderr, "%.60s\n", graph_dotted_line);
1699 		fprintf(stderr, "perf_event_attr:\n");
1700 		perf_event_attr__fprintf(stderr, &evsel->attr, __open_attr__fprintf, NULL);
1701 		fprintf(stderr, "%.60s\n", graph_dotted_line);
1702 	}
1703 
1704 	for (cpu = 0; cpu < cpus->nr; cpu++) {
1705 
1706 		for (thread = 0; thread < nthreads; thread++) {
1707 			int fd, group_fd;
1708 
1709 			if (!evsel->cgrp && !evsel->system_wide)
1710 				pid = thread_map__pid(threads, thread);
1711 
1712 			group_fd = get_group_fd(evsel, cpu, thread);
1713 retry_open:
1714 			pr_debug2("sys_perf_event_open: pid %d  cpu %d  group_fd %d  flags %#lx",
1715 				  pid, cpus->map[cpu], group_fd, flags);
1716 
1717 			test_attr__ready();
1718 
1719 			fd = sys_perf_event_open(&evsel->attr, pid, cpus->map[cpu],
1720 						 group_fd, flags);
1721 
1722 			FD(evsel, cpu, thread) = fd;
1723 
1724 			if (fd < 0) {
1725 				err = -errno;
1726 
1727 				if (ignore_missing_thread(evsel, threads, thread, err)) {
1728 					/*
1729 					 * We just removed 1 thread, so take a step
1730 					 * back on thread index and lower the upper
1731 					 * nthreads limit.
1732 					 */
1733 					nthreads--;
1734 					thread--;
1735 
1736 					/* ... and pretend like nothing have happened. */
1737 					err = 0;
1738 					continue;
1739 				}
1740 
1741 				pr_debug2("\nsys_perf_event_open failed, error %d\n",
1742 					  err);
1743 				goto try_fallback;
1744 			}
1745 
1746 			pr_debug2(" = %d\n", fd);
1747 
1748 			if (evsel->bpf_fd >= 0) {
1749 				int evt_fd = fd;
1750 				int bpf_fd = evsel->bpf_fd;
1751 
1752 				err = ioctl(evt_fd,
1753 					    PERF_EVENT_IOC_SET_BPF,
1754 					    bpf_fd);
1755 				if (err && errno != EEXIST) {
1756 					pr_err("failed to attach bpf fd %d: %s\n",
1757 					       bpf_fd, strerror(errno));
1758 					err = -EINVAL;
1759 					goto out_close;
1760 				}
1761 			}
1762 
1763 			set_rlimit = NO_CHANGE;
1764 
1765 			/*
1766 			 * If we succeeded but had to kill clockid, fail and
1767 			 * have perf_evsel__open_strerror() print us a nice
1768 			 * error.
1769 			 */
1770 			if (perf_missing_features.clockid ||
1771 			    perf_missing_features.clockid_wrong) {
1772 				err = -EINVAL;
1773 				goto out_close;
1774 			}
1775 		}
1776 	}
1777 
1778 	return 0;
1779 
1780 try_fallback:
1781 	/*
1782 	 * perf stat needs between 5 and 22 fds per CPU. When we run out
1783 	 * of them try to increase the limits.
1784 	 */
1785 	if (err == -EMFILE && set_rlimit < INCREASED_MAX) {
1786 		struct rlimit l;
1787 		int old_errno = errno;
1788 
1789 		if (getrlimit(RLIMIT_NOFILE, &l) == 0) {
1790 			if (set_rlimit == NO_CHANGE)
1791 				l.rlim_cur = l.rlim_max;
1792 			else {
1793 				l.rlim_cur = l.rlim_max + 1000;
1794 				l.rlim_max = l.rlim_cur;
1795 			}
1796 			if (setrlimit(RLIMIT_NOFILE, &l) == 0) {
1797 				set_rlimit++;
1798 				errno = old_errno;
1799 				goto retry_open;
1800 			}
1801 		}
1802 		errno = old_errno;
1803 	}
1804 
1805 	if (err != -EINVAL || cpu > 0 || thread > 0)
1806 		goto out_close;
1807 
1808 	/*
1809 	 * Must probe features in the order they were added to the
1810 	 * perf_event_attr interface.
1811 	 */
1812 	if (!perf_missing_features.write_backward && evsel->attr.write_backward) {
1813 		perf_missing_features.write_backward = true;
1814 		pr_debug2("switching off write_backward\n");
1815 		goto out_close;
1816 	} else if (!perf_missing_features.clockid_wrong && evsel->attr.use_clockid) {
1817 		perf_missing_features.clockid_wrong = true;
1818 		pr_debug2("switching off clockid\n");
1819 		goto fallback_missing_features;
1820 	} else if (!perf_missing_features.clockid && evsel->attr.use_clockid) {
1821 		perf_missing_features.clockid = true;
1822 		pr_debug2("switching off use_clockid\n");
1823 		goto fallback_missing_features;
1824 	} else if (!perf_missing_features.cloexec && (flags & PERF_FLAG_FD_CLOEXEC)) {
1825 		perf_missing_features.cloexec = true;
1826 		pr_debug2("switching off cloexec flag\n");
1827 		goto fallback_missing_features;
1828 	} else if (!perf_missing_features.mmap2 && evsel->attr.mmap2) {
1829 		perf_missing_features.mmap2 = true;
1830 		pr_debug2("switching off mmap2\n");
1831 		goto fallback_missing_features;
1832 	} else if (!perf_missing_features.exclude_guest &&
1833 		   (evsel->attr.exclude_guest || evsel->attr.exclude_host)) {
1834 		perf_missing_features.exclude_guest = true;
1835 		pr_debug2("switching off exclude_guest, exclude_host\n");
1836 		goto fallback_missing_features;
1837 	} else if (!perf_missing_features.sample_id_all) {
1838 		perf_missing_features.sample_id_all = true;
1839 		pr_debug2("switching off sample_id_all\n");
1840 		goto retry_sample_id;
1841 	} else if (!perf_missing_features.lbr_flags &&
1842 			(evsel->attr.branch_sample_type &
1843 			 (PERF_SAMPLE_BRANCH_NO_CYCLES |
1844 			  PERF_SAMPLE_BRANCH_NO_FLAGS))) {
1845 		perf_missing_features.lbr_flags = true;
1846 		pr_debug2("switching off branch sample type no (cycles/flags)\n");
1847 		goto fallback_missing_features;
1848 	} else if (!perf_missing_features.group_read &&
1849 		    evsel->attr.inherit &&
1850 		   (evsel->attr.read_format & PERF_FORMAT_GROUP)) {
1851 		perf_missing_features.group_read = true;
1852 		pr_debug2("switching off group read\n");
1853 		goto fallback_missing_features;
1854 	}
1855 out_close:
1856 	do {
1857 		while (--thread >= 0) {
1858 			close(FD(evsel, cpu, thread));
1859 			FD(evsel, cpu, thread) = -1;
1860 		}
1861 		thread = nthreads;
1862 	} while (--cpu >= 0);
1863 	return err;
1864 }
1865 
1866 void perf_evsel__close(struct perf_evsel *evsel)
1867 {
1868 	if (evsel->fd == NULL)
1869 		return;
1870 
1871 	perf_evsel__close_fd(evsel);
1872 	perf_evsel__free_fd(evsel);
1873 }
1874 
1875 int perf_evsel__open_per_cpu(struct perf_evsel *evsel,
1876 			     struct cpu_map *cpus)
1877 {
1878 	return perf_evsel__open(evsel, cpus, NULL);
1879 }
1880 
1881 int perf_evsel__open_per_thread(struct perf_evsel *evsel,
1882 				struct thread_map *threads)
1883 {
1884 	return perf_evsel__open(evsel, NULL, threads);
1885 }
1886 
1887 static int perf_evsel__parse_id_sample(const struct perf_evsel *evsel,
1888 				       const union perf_event *event,
1889 				       struct perf_sample *sample)
1890 {
1891 	u64 type = evsel->attr.sample_type;
1892 	const u64 *array = event->sample.array;
1893 	bool swapped = evsel->needs_swap;
1894 	union u64_swap u;
1895 
1896 	array += ((event->header.size -
1897 		   sizeof(event->header)) / sizeof(u64)) - 1;
1898 
1899 	if (type & PERF_SAMPLE_IDENTIFIER) {
1900 		sample->id = *array;
1901 		array--;
1902 	}
1903 
1904 	if (type & PERF_SAMPLE_CPU) {
1905 		u.val64 = *array;
1906 		if (swapped) {
1907 			/* undo swap of u64, then swap on individual u32s */
1908 			u.val64 = bswap_64(u.val64);
1909 			u.val32[0] = bswap_32(u.val32[0]);
1910 		}
1911 
1912 		sample->cpu = u.val32[0];
1913 		array--;
1914 	}
1915 
1916 	if (type & PERF_SAMPLE_STREAM_ID) {
1917 		sample->stream_id = *array;
1918 		array--;
1919 	}
1920 
1921 	if (type & PERF_SAMPLE_ID) {
1922 		sample->id = *array;
1923 		array--;
1924 	}
1925 
1926 	if (type & PERF_SAMPLE_TIME) {
1927 		sample->time = *array;
1928 		array--;
1929 	}
1930 
1931 	if (type & PERF_SAMPLE_TID) {
1932 		u.val64 = *array;
1933 		if (swapped) {
1934 			/* undo swap of u64, then swap on individual u32s */
1935 			u.val64 = bswap_64(u.val64);
1936 			u.val32[0] = bswap_32(u.val32[0]);
1937 			u.val32[1] = bswap_32(u.val32[1]);
1938 		}
1939 
1940 		sample->pid = u.val32[0];
1941 		sample->tid = u.val32[1];
1942 		array--;
1943 	}
1944 
1945 	return 0;
1946 }
1947 
1948 static inline bool overflow(const void *endp, u16 max_size, const void *offset,
1949 			    u64 size)
1950 {
1951 	return size > max_size || offset + size > endp;
1952 }
1953 
1954 #define OVERFLOW_CHECK(offset, size, max_size)				\
1955 	do {								\
1956 		if (overflow(endp, (max_size), (offset), (size)))	\
1957 			return -EFAULT;					\
1958 	} while (0)
1959 
1960 #define OVERFLOW_CHECK_u64(offset) \
1961 	OVERFLOW_CHECK(offset, sizeof(u64), sizeof(u64))
1962 
1963 int perf_evsel__parse_sample(struct perf_evsel *evsel, union perf_event *event,
1964 			     struct perf_sample *data)
1965 {
1966 	u64 type = evsel->attr.sample_type;
1967 	bool swapped = evsel->needs_swap;
1968 	const u64 *array;
1969 	u16 max_size = event->header.size;
1970 	const void *endp = (void *)event + max_size;
1971 	u64 sz;
1972 
1973 	/*
1974 	 * used for cross-endian analysis. See git commit 65014ab3
1975 	 * for why this goofiness is needed.
1976 	 */
1977 	union u64_swap u;
1978 
1979 	memset(data, 0, sizeof(*data));
1980 	data->cpu = data->pid = data->tid = -1;
1981 	data->stream_id = data->id = data->time = -1ULL;
1982 	data->period = evsel->attr.sample_period;
1983 	data->cpumode = event->header.misc & PERF_RECORD_MISC_CPUMODE_MASK;
1984 
1985 	if (event->header.type != PERF_RECORD_SAMPLE) {
1986 		if (!evsel->attr.sample_id_all)
1987 			return 0;
1988 		return perf_evsel__parse_id_sample(evsel, event, data);
1989 	}
1990 
1991 	array = event->sample.array;
1992 
1993 	/*
1994 	 * The evsel's sample_size is based on PERF_SAMPLE_MASK which includes
1995 	 * up to PERF_SAMPLE_PERIOD.  After that overflow() must be used to
1996 	 * check the format does not go past the end of the event.
1997 	 */
1998 	if (evsel->sample_size + sizeof(event->header) > event->header.size)
1999 		return -EFAULT;
2000 
2001 	data->id = -1ULL;
2002 	if (type & PERF_SAMPLE_IDENTIFIER) {
2003 		data->id = *array;
2004 		array++;
2005 	}
2006 
2007 	if (type & PERF_SAMPLE_IP) {
2008 		data->ip = *array;
2009 		array++;
2010 	}
2011 
2012 	if (type & PERF_SAMPLE_TID) {
2013 		u.val64 = *array;
2014 		if (swapped) {
2015 			/* undo swap of u64, then swap on individual u32s */
2016 			u.val64 = bswap_64(u.val64);
2017 			u.val32[0] = bswap_32(u.val32[0]);
2018 			u.val32[1] = bswap_32(u.val32[1]);
2019 		}
2020 
2021 		data->pid = u.val32[0];
2022 		data->tid = u.val32[1];
2023 		array++;
2024 	}
2025 
2026 	if (type & PERF_SAMPLE_TIME) {
2027 		data->time = *array;
2028 		array++;
2029 	}
2030 
2031 	data->addr = 0;
2032 	if (type & PERF_SAMPLE_ADDR) {
2033 		data->addr = *array;
2034 		array++;
2035 	}
2036 
2037 	if (type & PERF_SAMPLE_ID) {
2038 		data->id = *array;
2039 		array++;
2040 	}
2041 
2042 	if (type & PERF_SAMPLE_STREAM_ID) {
2043 		data->stream_id = *array;
2044 		array++;
2045 	}
2046 
2047 	if (type & PERF_SAMPLE_CPU) {
2048 
2049 		u.val64 = *array;
2050 		if (swapped) {
2051 			/* undo swap of u64, then swap on individual u32s */
2052 			u.val64 = bswap_64(u.val64);
2053 			u.val32[0] = bswap_32(u.val32[0]);
2054 		}
2055 
2056 		data->cpu = u.val32[0];
2057 		array++;
2058 	}
2059 
2060 	if (type & PERF_SAMPLE_PERIOD) {
2061 		data->period = *array;
2062 		array++;
2063 	}
2064 
2065 	if (type & PERF_SAMPLE_READ) {
2066 		u64 read_format = evsel->attr.read_format;
2067 
2068 		OVERFLOW_CHECK_u64(array);
2069 		if (read_format & PERF_FORMAT_GROUP)
2070 			data->read.group.nr = *array;
2071 		else
2072 			data->read.one.value = *array;
2073 
2074 		array++;
2075 
2076 		if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) {
2077 			OVERFLOW_CHECK_u64(array);
2078 			data->read.time_enabled = *array;
2079 			array++;
2080 		}
2081 
2082 		if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) {
2083 			OVERFLOW_CHECK_u64(array);
2084 			data->read.time_running = *array;
2085 			array++;
2086 		}
2087 
2088 		/* PERF_FORMAT_ID is forced for PERF_SAMPLE_READ */
2089 		if (read_format & PERF_FORMAT_GROUP) {
2090 			const u64 max_group_nr = UINT64_MAX /
2091 					sizeof(struct sample_read_value);
2092 
2093 			if (data->read.group.nr > max_group_nr)
2094 				return -EFAULT;
2095 			sz = data->read.group.nr *
2096 			     sizeof(struct sample_read_value);
2097 			OVERFLOW_CHECK(array, sz, max_size);
2098 			data->read.group.values =
2099 					(struct sample_read_value *)array;
2100 			array = (void *)array + sz;
2101 		} else {
2102 			OVERFLOW_CHECK_u64(array);
2103 			data->read.one.id = *array;
2104 			array++;
2105 		}
2106 	}
2107 
2108 	if (type & PERF_SAMPLE_CALLCHAIN) {
2109 		const u64 max_callchain_nr = UINT64_MAX / sizeof(u64);
2110 
2111 		OVERFLOW_CHECK_u64(array);
2112 		data->callchain = (struct ip_callchain *)array++;
2113 		if (data->callchain->nr > max_callchain_nr)
2114 			return -EFAULT;
2115 		sz = data->callchain->nr * sizeof(u64);
2116 		OVERFLOW_CHECK(array, sz, max_size);
2117 		array = (void *)array + sz;
2118 	}
2119 
2120 	if (type & PERF_SAMPLE_RAW) {
2121 		OVERFLOW_CHECK_u64(array);
2122 		u.val64 = *array;
2123 		if (WARN_ONCE(swapped,
2124 			      "Endianness of raw data not corrected!\n")) {
2125 			/* undo swap of u64, then swap on individual u32s */
2126 			u.val64 = bswap_64(u.val64);
2127 			u.val32[0] = bswap_32(u.val32[0]);
2128 			u.val32[1] = bswap_32(u.val32[1]);
2129 		}
2130 		data->raw_size = u.val32[0];
2131 		array = (void *)array + sizeof(u32);
2132 
2133 		OVERFLOW_CHECK(array, data->raw_size, max_size);
2134 		data->raw_data = (void *)array;
2135 		array = (void *)array + data->raw_size;
2136 	}
2137 
2138 	if (type & PERF_SAMPLE_BRANCH_STACK) {
2139 		const u64 max_branch_nr = UINT64_MAX /
2140 					  sizeof(struct branch_entry);
2141 
2142 		OVERFLOW_CHECK_u64(array);
2143 		data->branch_stack = (struct branch_stack *)array++;
2144 
2145 		if (data->branch_stack->nr > max_branch_nr)
2146 			return -EFAULT;
2147 		sz = data->branch_stack->nr * sizeof(struct branch_entry);
2148 		OVERFLOW_CHECK(array, sz, max_size);
2149 		array = (void *)array + sz;
2150 	}
2151 
2152 	if (type & PERF_SAMPLE_REGS_USER) {
2153 		OVERFLOW_CHECK_u64(array);
2154 		data->user_regs.abi = *array;
2155 		array++;
2156 
2157 		if (data->user_regs.abi) {
2158 			u64 mask = evsel->attr.sample_regs_user;
2159 
2160 			sz = hweight_long(mask) * sizeof(u64);
2161 			OVERFLOW_CHECK(array, sz, max_size);
2162 			data->user_regs.mask = mask;
2163 			data->user_regs.regs = (u64 *)array;
2164 			array = (void *)array + sz;
2165 		}
2166 	}
2167 
2168 	if (type & PERF_SAMPLE_STACK_USER) {
2169 		OVERFLOW_CHECK_u64(array);
2170 		sz = *array++;
2171 
2172 		data->user_stack.offset = ((char *)(array - 1)
2173 					  - (char *) event);
2174 
2175 		if (!sz) {
2176 			data->user_stack.size = 0;
2177 		} else {
2178 			OVERFLOW_CHECK(array, sz, max_size);
2179 			data->user_stack.data = (char *)array;
2180 			array = (void *)array + sz;
2181 			OVERFLOW_CHECK_u64(array);
2182 			data->user_stack.size = *array++;
2183 			if (WARN_ONCE(data->user_stack.size > sz,
2184 				      "user stack dump failure\n"))
2185 				return -EFAULT;
2186 		}
2187 	}
2188 
2189 	if (type & PERF_SAMPLE_WEIGHT) {
2190 		OVERFLOW_CHECK_u64(array);
2191 		data->weight = *array;
2192 		array++;
2193 	}
2194 
2195 	data->data_src = PERF_MEM_DATA_SRC_NONE;
2196 	if (type & PERF_SAMPLE_DATA_SRC) {
2197 		OVERFLOW_CHECK_u64(array);
2198 		data->data_src = *array;
2199 		array++;
2200 	}
2201 
2202 	data->transaction = 0;
2203 	if (type & PERF_SAMPLE_TRANSACTION) {
2204 		OVERFLOW_CHECK_u64(array);
2205 		data->transaction = *array;
2206 		array++;
2207 	}
2208 
2209 	data->intr_regs.abi = PERF_SAMPLE_REGS_ABI_NONE;
2210 	if (type & PERF_SAMPLE_REGS_INTR) {
2211 		OVERFLOW_CHECK_u64(array);
2212 		data->intr_regs.abi = *array;
2213 		array++;
2214 
2215 		if (data->intr_regs.abi != PERF_SAMPLE_REGS_ABI_NONE) {
2216 			u64 mask = evsel->attr.sample_regs_intr;
2217 
2218 			sz = hweight_long(mask) * sizeof(u64);
2219 			OVERFLOW_CHECK(array, sz, max_size);
2220 			data->intr_regs.mask = mask;
2221 			data->intr_regs.regs = (u64 *)array;
2222 			array = (void *)array + sz;
2223 		}
2224 	}
2225 
2226 	data->phys_addr = 0;
2227 	if (type & PERF_SAMPLE_PHYS_ADDR) {
2228 		data->phys_addr = *array;
2229 		array++;
2230 	}
2231 
2232 	return 0;
2233 }
2234 
2235 size_t perf_event__sample_event_size(const struct perf_sample *sample, u64 type,
2236 				     u64 read_format)
2237 {
2238 	size_t sz, result = sizeof(struct sample_event);
2239 
2240 	if (type & PERF_SAMPLE_IDENTIFIER)
2241 		result += sizeof(u64);
2242 
2243 	if (type & PERF_SAMPLE_IP)
2244 		result += sizeof(u64);
2245 
2246 	if (type & PERF_SAMPLE_TID)
2247 		result += sizeof(u64);
2248 
2249 	if (type & PERF_SAMPLE_TIME)
2250 		result += sizeof(u64);
2251 
2252 	if (type & PERF_SAMPLE_ADDR)
2253 		result += sizeof(u64);
2254 
2255 	if (type & PERF_SAMPLE_ID)
2256 		result += sizeof(u64);
2257 
2258 	if (type & PERF_SAMPLE_STREAM_ID)
2259 		result += sizeof(u64);
2260 
2261 	if (type & PERF_SAMPLE_CPU)
2262 		result += sizeof(u64);
2263 
2264 	if (type & PERF_SAMPLE_PERIOD)
2265 		result += sizeof(u64);
2266 
2267 	if (type & PERF_SAMPLE_READ) {
2268 		result += sizeof(u64);
2269 		if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED)
2270 			result += sizeof(u64);
2271 		if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING)
2272 			result += sizeof(u64);
2273 		/* PERF_FORMAT_ID is forced for PERF_SAMPLE_READ */
2274 		if (read_format & PERF_FORMAT_GROUP) {
2275 			sz = sample->read.group.nr *
2276 			     sizeof(struct sample_read_value);
2277 			result += sz;
2278 		} else {
2279 			result += sizeof(u64);
2280 		}
2281 	}
2282 
2283 	if (type & PERF_SAMPLE_CALLCHAIN) {
2284 		sz = (sample->callchain->nr + 1) * sizeof(u64);
2285 		result += sz;
2286 	}
2287 
2288 	if (type & PERF_SAMPLE_RAW) {
2289 		result += sizeof(u32);
2290 		result += sample->raw_size;
2291 	}
2292 
2293 	if (type & PERF_SAMPLE_BRANCH_STACK) {
2294 		sz = sample->branch_stack->nr * sizeof(struct branch_entry);
2295 		sz += sizeof(u64);
2296 		result += sz;
2297 	}
2298 
2299 	if (type & PERF_SAMPLE_REGS_USER) {
2300 		if (sample->user_regs.abi) {
2301 			result += sizeof(u64);
2302 			sz = hweight_long(sample->user_regs.mask) * sizeof(u64);
2303 			result += sz;
2304 		} else {
2305 			result += sizeof(u64);
2306 		}
2307 	}
2308 
2309 	if (type & PERF_SAMPLE_STACK_USER) {
2310 		sz = sample->user_stack.size;
2311 		result += sizeof(u64);
2312 		if (sz) {
2313 			result += sz;
2314 			result += sizeof(u64);
2315 		}
2316 	}
2317 
2318 	if (type & PERF_SAMPLE_WEIGHT)
2319 		result += sizeof(u64);
2320 
2321 	if (type & PERF_SAMPLE_DATA_SRC)
2322 		result += sizeof(u64);
2323 
2324 	if (type & PERF_SAMPLE_TRANSACTION)
2325 		result += sizeof(u64);
2326 
2327 	if (type & PERF_SAMPLE_REGS_INTR) {
2328 		if (sample->intr_regs.abi) {
2329 			result += sizeof(u64);
2330 			sz = hweight_long(sample->intr_regs.mask) * sizeof(u64);
2331 			result += sz;
2332 		} else {
2333 			result += sizeof(u64);
2334 		}
2335 	}
2336 
2337 	if (type & PERF_SAMPLE_PHYS_ADDR)
2338 		result += sizeof(u64);
2339 
2340 	return result;
2341 }
2342 
2343 int perf_event__synthesize_sample(union perf_event *event, u64 type,
2344 				  u64 read_format,
2345 				  const struct perf_sample *sample,
2346 				  bool swapped)
2347 {
2348 	u64 *array;
2349 	size_t sz;
2350 	/*
2351 	 * used for cross-endian analysis. See git commit 65014ab3
2352 	 * for why this goofiness is needed.
2353 	 */
2354 	union u64_swap u;
2355 
2356 	array = event->sample.array;
2357 
2358 	if (type & PERF_SAMPLE_IDENTIFIER) {
2359 		*array = sample->id;
2360 		array++;
2361 	}
2362 
2363 	if (type & PERF_SAMPLE_IP) {
2364 		*array = sample->ip;
2365 		array++;
2366 	}
2367 
2368 	if (type & PERF_SAMPLE_TID) {
2369 		u.val32[0] = sample->pid;
2370 		u.val32[1] = sample->tid;
2371 		if (swapped) {
2372 			/*
2373 			 * Inverse of what is done in perf_evsel__parse_sample
2374 			 */
2375 			u.val32[0] = bswap_32(u.val32[0]);
2376 			u.val32[1] = bswap_32(u.val32[1]);
2377 			u.val64 = bswap_64(u.val64);
2378 		}
2379 
2380 		*array = u.val64;
2381 		array++;
2382 	}
2383 
2384 	if (type & PERF_SAMPLE_TIME) {
2385 		*array = sample->time;
2386 		array++;
2387 	}
2388 
2389 	if (type & PERF_SAMPLE_ADDR) {
2390 		*array = sample->addr;
2391 		array++;
2392 	}
2393 
2394 	if (type & PERF_SAMPLE_ID) {
2395 		*array = sample->id;
2396 		array++;
2397 	}
2398 
2399 	if (type & PERF_SAMPLE_STREAM_ID) {
2400 		*array = sample->stream_id;
2401 		array++;
2402 	}
2403 
2404 	if (type & PERF_SAMPLE_CPU) {
2405 		u.val32[0] = sample->cpu;
2406 		if (swapped) {
2407 			/*
2408 			 * Inverse of what is done in perf_evsel__parse_sample
2409 			 */
2410 			u.val32[0] = bswap_32(u.val32[0]);
2411 			u.val64 = bswap_64(u.val64);
2412 		}
2413 		*array = u.val64;
2414 		array++;
2415 	}
2416 
2417 	if (type & PERF_SAMPLE_PERIOD) {
2418 		*array = sample->period;
2419 		array++;
2420 	}
2421 
2422 	if (type & PERF_SAMPLE_READ) {
2423 		if (read_format & PERF_FORMAT_GROUP)
2424 			*array = sample->read.group.nr;
2425 		else
2426 			*array = sample->read.one.value;
2427 		array++;
2428 
2429 		if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) {
2430 			*array = sample->read.time_enabled;
2431 			array++;
2432 		}
2433 
2434 		if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) {
2435 			*array = sample->read.time_running;
2436 			array++;
2437 		}
2438 
2439 		/* PERF_FORMAT_ID is forced for PERF_SAMPLE_READ */
2440 		if (read_format & PERF_FORMAT_GROUP) {
2441 			sz = sample->read.group.nr *
2442 			     sizeof(struct sample_read_value);
2443 			memcpy(array, sample->read.group.values, sz);
2444 			array = (void *)array + sz;
2445 		} else {
2446 			*array = sample->read.one.id;
2447 			array++;
2448 		}
2449 	}
2450 
2451 	if (type & PERF_SAMPLE_CALLCHAIN) {
2452 		sz = (sample->callchain->nr + 1) * sizeof(u64);
2453 		memcpy(array, sample->callchain, sz);
2454 		array = (void *)array + sz;
2455 	}
2456 
2457 	if (type & PERF_SAMPLE_RAW) {
2458 		u.val32[0] = sample->raw_size;
2459 		if (WARN_ONCE(swapped,
2460 			      "Endianness of raw data not corrected!\n")) {
2461 			/*
2462 			 * Inverse of what is done in perf_evsel__parse_sample
2463 			 */
2464 			u.val32[0] = bswap_32(u.val32[0]);
2465 			u.val32[1] = bswap_32(u.val32[1]);
2466 			u.val64 = bswap_64(u.val64);
2467 		}
2468 		*array = u.val64;
2469 		array = (void *)array + sizeof(u32);
2470 
2471 		memcpy(array, sample->raw_data, sample->raw_size);
2472 		array = (void *)array + sample->raw_size;
2473 	}
2474 
2475 	if (type & PERF_SAMPLE_BRANCH_STACK) {
2476 		sz = sample->branch_stack->nr * sizeof(struct branch_entry);
2477 		sz += sizeof(u64);
2478 		memcpy(array, sample->branch_stack, sz);
2479 		array = (void *)array + sz;
2480 	}
2481 
2482 	if (type & PERF_SAMPLE_REGS_USER) {
2483 		if (sample->user_regs.abi) {
2484 			*array++ = sample->user_regs.abi;
2485 			sz = hweight_long(sample->user_regs.mask) * sizeof(u64);
2486 			memcpy(array, sample->user_regs.regs, sz);
2487 			array = (void *)array + sz;
2488 		} else {
2489 			*array++ = 0;
2490 		}
2491 	}
2492 
2493 	if (type & PERF_SAMPLE_STACK_USER) {
2494 		sz = sample->user_stack.size;
2495 		*array++ = sz;
2496 		if (sz) {
2497 			memcpy(array, sample->user_stack.data, sz);
2498 			array = (void *)array + sz;
2499 			*array++ = sz;
2500 		}
2501 	}
2502 
2503 	if (type & PERF_SAMPLE_WEIGHT) {
2504 		*array = sample->weight;
2505 		array++;
2506 	}
2507 
2508 	if (type & PERF_SAMPLE_DATA_SRC) {
2509 		*array = sample->data_src;
2510 		array++;
2511 	}
2512 
2513 	if (type & PERF_SAMPLE_TRANSACTION) {
2514 		*array = sample->transaction;
2515 		array++;
2516 	}
2517 
2518 	if (type & PERF_SAMPLE_REGS_INTR) {
2519 		if (sample->intr_regs.abi) {
2520 			*array++ = sample->intr_regs.abi;
2521 			sz = hweight_long(sample->intr_regs.mask) * sizeof(u64);
2522 			memcpy(array, sample->intr_regs.regs, sz);
2523 			array = (void *)array + sz;
2524 		} else {
2525 			*array++ = 0;
2526 		}
2527 	}
2528 
2529 	if (type & PERF_SAMPLE_PHYS_ADDR) {
2530 		*array = sample->phys_addr;
2531 		array++;
2532 	}
2533 
2534 	return 0;
2535 }
2536 
2537 struct format_field *perf_evsel__field(struct perf_evsel *evsel, const char *name)
2538 {
2539 	return pevent_find_field(evsel->tp_format, name);
2540 }
2541 
2542 void *perf_evsel__rawptr(struct perf_evsel *evsel, struct perf_sample *sample,
2543 			 const char *name)
2544 {
2545 	struct format_field *field = perf_evsel__field(evsel, name);
2546 	int offset;
2547 
2548 	if (!field)
2549 		return NULL;
2550 
2551 	offset = field->offset;
2552 
2553 	if (field->flags & FIELD_IS_DYNAMIC) {
2554 		offset = *(int *)(sample->raw_data + field->offset);
2555 		offset &= 0xffff;
2556 	}
2557 
2558 	return sample->raw_data + offset;
2559 }
2560 
2561 u64 format_field__intval(struct format_field *field, struct perf_sample *sample,
2562 			 bool needs_swap)
2563 {
2564 	u64 value;
2565 	void *ptr = sample->raw_data + field->offset;
2566 
2567 	switch (field->size) {
2568 	case 1:
2569 		return *(u8 *)ptr;
2570 	case 2:
2571 		value = *(u16 *)ptr;
2572 		break;
2573 	case 4:
2574 		value = *(u32 *)ptr;
2575 		break;
2576 	case 8:
2577 		memcpy(&value, ptr, sizeof(u64));
2578 		break;
2579 	default:
2580 		return 0;
2581 	}
2582 
2583 	if (!needs_swap)
2584 		return value;
2585 
2586 	switch (field->size) {
2587 	case 2:
2588 		return bswap_16(value);
2589 	case 4:
2590 		return bswap_32(value);
2591 	case 8:
2592 		return bswap_64(value);
2593 	default:
2594 		return 0;
2595 	}
2596 
2597 	return 0;
2598 }
2599 
2600 u64 perf_evsel__intval(struct perf_evsel *evsel, struct perf_sample *sample,
2601 		       const char *name)
2602 {
2603 	struct format_field *field = perf_evsel__field(evsel, name);
2604 
2605 	if (!field)
2606 		return 0;
2607 
2608 	return field ? format_field__intval(field, sample, evsel->needs_swap) : 0;
2609 }
2610 
2611 bool perf_evsel__fallback(struct perf_evsel *evsel, int err,
2612 			  char *msg, size_t msgsize)
2613 {
2614 	int paranoid;
2615 
2616 	if ((err == ENOENT || err == ENXIO || err == ENODEV) &&
2617 	    evsel->attr.type   == PERF_TYPE_HARDWARE &&
2618 	    evsel->attr.config == PERF_COUNT_HW_CPU_CYCLES) {
2619 		/*
2620 		 * If it's cycles then fall back to hrtimer based
2621 		 * cpu-clock-tick sw counter, which is always available even if
2622 		 * no PMU support.
2623 		 *
2624 		 * PPC returns ENXIO until 2.6.37 (behavior changed with commit
2625 		 * b0a873e).
2626 		 */
2627 		scnprintf(msg, msgsize, "%s",
2628 "The cycles event is not supported, trying to fall back to cpu-clock-ticks");
2629 
2630 		evsel->attr.type   = PERF_TYPE_SOFTWARE;
2631 		evsel->attr.config = PERF_COUNT_SW_CPU_CLOCK;
2632 
2633 		zfree(&evsel->name);
2634 		return true;
2635 	} else if (err == EACCES && !evsel->attr.exclude_kernel &&
2636 		   (paranoid = perf_event_paranoid()) > 1) {
2637 		const char *name = perf_evsel__name(evsel);
2638 		char *new_name;
2639 
2640 		if (asprintf(&new_name, "%s%su", name, strchr(name, ':') ? "" : ":") < 0)
2641 			return false;
2642 
2643 		if (evsel->name)
2644 			free(evsel->name);
2645 		evsel->name = new_name;
2646 		scnprintf(msg, msgsize,
2647 "kernel.perf_event_paranoid=%d, trying to fall back to excluding kernel samples", paranoid);
2648 		evsel->attr.exclude_kernel = 1;
2649 
2650 		return true;
2651 	}
2652 
2653 	return false;
2654 }
2655 
2656 static bool find_process(const char *name)
2657 {
2658 	size_t len = strlen(name);
2659 	DIR *dir;
2660 	struct dirent *d;
2661 	int ret = -1;
2662 
2663 	dir = opendir(procfs__mountpoint());
2664 	if (!dir)
2665 		return false;
2666 
2667 	/* Walk through the directory. */
2668 	while (ret && (d = readdir(dir)) != NULL) {
2669 		char path[PATH_MAX];
2670 		char *data;
2671 		size_t size;
2672 
2673 		if ((d->d_type != DT_DIR) ||
2674 		     !strcmp(".", d->d_name) ||
2675 		     !strcmp("..", d->d_name))
2676 			continue;
2677 
2678 		scnprintf(path, sizeof(path), "%s/%s/comm",
2679 			  procfs__mountpoint(), d->d_name);
2680 
2681 		if (filename__read_str(path, &data, &size))
2682 			continue;
2683 
2684 		ret = strncmp(name, data, len);
2685 		free(data);
2686 	}
2687 
2688 	closedir(dir);
2689 	return ret ? false : true;
2690 }
2691 
2692 int perf_evsel__open_strerror(struct perf_evsel *evsel, struct target *target,
2693 			      int err, char *msg, size_t size)
2694 {
2695 	char sbuf[STRERR_BUFSIZE];
2696 	int printed = 0;
2697 
2698 	switch (err) {
2699 	case EPERM:
2700 	case EACCES:
2701 		if (err == EPERM)
2702 			printed = scnprintf(msg, size,
2703 				"No permission to enable %s event.\n\n",
2704 				perf_evsel__name(evsel));
2705 
2706 		return scnprintf(msg + printed, size - printed,
2707 		 "You may not have permission to collect %sstats.\n\n"
2708 		 "Consider tweaking /proc/sys/kernel/perf_event_paranoid,\n"
2709 		 "which controls use of the performance events system by\n"
2710 		 "unprivileged users (without CAP_SYS_ADMIN).\n\n"
2711 		 "The current value is %d:\n\n"
2712 		 "  -1: Allow use of (almost) all events by all users\n"
2713 		 "      Ignore mlock limit after perf_event_mlock_kb without CAP_IPC_LOCK\n"
2714 		 ">= 0: Disallow ftrace function tracepoint by users without CAP_SYS_ADMIN\n"
2715 		 "      Disallow raw tracepoint access by users without CAP_SYS_ADMIN\n"
2716 		 ">= 1: Disallow CPU event access by users without CAP_SYS_ADMIN\n"
2717 		 ">= 2: Disallow kernel profiling by users without CAP_SYS_ADMIN\n\n"
2718 		 "To make this setting permanent, edit /etc/sysctl.conf too, e.g.:\n\n"
2719 		 "	kernel.perf_event_paranoid = -1\n" ,
2720 				 target->system_wide ? "system-wide " : "",
2721 				 perf_event_paranoid());
2722 	case ENOENT:
2723 		return scnprintf(msg, size, "The %s event is not supported.",
2724 				 perf_evsel__name(evsel));
2725 	case EMFILE:
2726 		return scnprintf(msg, size, "%s",
2727 			 "Too many events are opened.\n"
2728 			 "Probably the maximum number of open file descriptors has been reached.\n"
2729 			 "Hint: Try again after reducing the number of events.\n"
2730 			 "Hint: Try increasing the limit with 'ulimit -n <limit>'");
2731 	case ENOMEM:
2732 		if ((evsel->attr.sample_type & PERF_SAMPLE_CALLCHAIN) != 0 &&
2733 		    access("/proc/sys/kernel/perf_event_max_stack", F_OK) == 0)
2734 			return scnprintf(msg, size,
2735 					 "Not enough memory to setup event with callchain.\n"
2736 					 "Hint: Try tweaking /proc/sys/kernel/perf_event_max_stack\n"
2737 					 "Hint: Current value: %d", sysctl_perf_event_max_stack);
2738 		break;
2739 	case ENODEV:
2740 		if (target->cpu_list)
2741 			return scnprintf(msg, size, "%s",
2742 	 "No such device - did you specify an out-of-range profile CPU?");
2743 		break;
2744 	case EOPNOTSUPP:
2745 		if (evsel->attr.sample_period != 0)
2746 			return scnprintf(msg, size, "%s",
2747 	"PMU Hardware doesn't support sampling/overflow-interrupts.");
2748 		if (evsel->attr.precise_ip)
2749 			return scnprintf(msg, size, "%s",
2750 	"\'precise\' request may not be supported. Try removing 'p' modifier.");
2751 #if defined(__i386__) || defined(__x86_64__)
2752 		if (evsel->attr.type == PERF_TYPE_HARDWARE)
2753 			return scnprintf(msg, size, "%s",
2754 	"No hardware sampling interrupt available.\n"
2755 	"No APIC? If so then you can boot the kernel with the \"lapic\" boot parameter to force-enable it.");
2756 #endif
2757 		break;
2758 	case EBUSY:
2759 		if (find_process("oprofiled"))
2760 			return scnprintf(msg, size,
2761 	"The PMU counters are busy/taken by another profiler.\n"
2762 	"We found oprofile daemon running, please stop it and try again.");
2763 		break;
2764 	case EINVAL:
2765 		if (evsel->attr.write_backward && perf_missing_features.write_backward)
2766 			return scnprintf(msg, size, "Reading from overwrite event is not supported by this kernel.");
2767 		if (perf_missing_features.clockid)
2768 			return scnprintf(msg, size, "clockid feature not supported.");
2769 		if (perf_missing_features.clockid_wrong)
2770 			return scnprintf(msg, size, "wrong clockid (%d).", clockid);
2771 		break;
2772 	default:
2773 		break;
2774 	}
2775 
2776 	return scnprintf(msg, size,
2777 	"The sys_perf_event_open() syscall returned with %d (%s) for event (%s).\n"
2778 	"/bin/dmesg may provide additional information.\n"
2779 	"No CONFIG_PERF_EVENTS=y kernel support configured?",
2780 			 err, str_error_r(err, sbuf, sizeof(sbuf)),
2781 			 perf_evsel__name(evsel));
2782 }
2783 
2784 char *perf_evsel__env_arch(struct perf_evsel *evsel)
2785 {
2786 	if (evsel && evsel->evlist && evsel->evlist->env)
2787 		return evsel->evlist->env->arch;
2788 	return NULL;
2789 }
2790 
2791 char *perf_evsel__env_cpuid(struct perf_evsel *evsel)
2792 {
2793 	if (evsel && evsel->evlist && evsel->evlist->env)
2794 		return evsel->evlist->env->cpuid;
2795 	return NULL;
2796 }
2797