xref: /openbmc/linux/tools/perf/util/session.c (revision 768dd3f3)
1 #include <linux/kernel.h>
2 #include <traceevent/event-parse.h>
3 
4 #include <byteswap.h>
5 #include <unistd.h>
6 #include <sys/types.h>
7 #include <sys/mman.h>
8 
9 #include "evlist.h"
10 #include "evsel.h"
11 #include "session.h"
12 #include "tool.h"
13 #include "sort.h"
14 #include "util.h"
15 #include "cpumap.h"
16 #include "perf_regs.h"
17 #include "asm/bug.h"
18 #include "auxtrace.h"
19 #include "thread-stack.h"
20 
21 static int perf_session__deliver_event(struct perf_session *session,
22 				       union perf_event *event,
23 				       struct perf_sample *sample,
24 				       struct perf_tool *tool,
25 				       u64 file_offset);
26 
27 static int perf_session__open(struct perf_session *session)
28 {
29 	struct perf_data_file *file = session->file;
30 
31 	if (perf_session__read_header(session) < 0) {
32 		pr_err("incompatible file format (rerun with -v to learn more)");
33 		return -1;
34 	}
35 
36 	if (perf_data_file__is_pipe(file))
37 		return 0;
38 
39 	if (!perf_evlist__valid_sample_type(session->evlist)) {
40 		pr_err("non matching sample_type");
41 		return -1;
42 	}
43 
44 	if (!perf_evlist__valid_sample_id_all(session->evlist)) {
45 		pr_err("non matching sample_id_all");
46 		return -1;
47 	}
48 
49 	if (!perf_evlist__valid_read_format(session->evlist)) {
50 		pr_err("non matching read_format");
51 		return -1;
52 	}
53 
54 	return 0;
55 }
56 
57 void perf_session__set_id_hdr_size(struct perf_session *session)
58 {
59 	u16 id_hdr_size = perf_evlist__id_hdr_size(session->evlist);
60 
61 	machines__set_id_hdr_size(&session->machines, id_hdr_size);
62 }
63 
64 int perf_session__create_kernel_maps(struct perf_session *session)
65 {
66 	int ret = machine__create_kernel_maps(&session->machines.host);
67 
68 	if (ret >= 0)
69 		ret = machines__create_guest_kernel_maps(&session->machines);
70 	return ret;
71 }
72 
73 static void perf_session__destroy_kernel_maps(struct perf_session *session)
74 {
75 	machines__destroy_kernel_maps(&session->machines);
76 }
77 
78 static bool perf_session__has_comm_exec(struct perf_session *session)
79 {
80 	struct perf_evsel *evsel;
81 
82 	evlist__for_each(session->evlist, evsel) {
83 		if (evsel->attr.comm_exec)
84 			return true;
85 	}
86 
87 	return false;
88 }
89 
90 static void perf_session__set_comm_exec(struct perf_session *session)
91 {
92 	bool comm_exec = perf_session__has_comm_exec(session);
93 
94 	machines__set_comm_exec(&session->machines, comm_exec);
95 }
96 
97 static int ordered_events__deliver_event(struct ordered_events *oe,
98 					 struct ordered_event *event)
99 {
100 	struct perf_sample sample;
101 	struct perf_session *session = container_of(oe, struct perf_session,
102 						    ordered_events);
103 	int ret = perf_evlist__parse_sample(session->evlist, event->event, &sample);
104 
105 	if (ret) {
106 		pr_err("Can't parse sample, err = %d\n", ret);
107 		return ret;
108 	}
109 
110 	return perf_session__deliver_event(session, event->event, &sample,
111 					   session->tool, event->file_offset);
112 }
113 
114 struct perf_session *perf_session__new(struct perf_data_file *file,
115 				       bool repipe, struct perf_tool *tool)
116 {
117 	struct perf_session *session = zalloc(sizeof(*session));
118 
119 	if (!session)
120 		goto out;
121 
122 	session->repipe = repipe;
123 	session->tool   = tool;
124 	INIT_LIST_HEAD(&session->auxtrace_index);
125 	machines__init(&session->machines);
126 	ordered_events__init(&session->ordered_events, ordered_events__deliver_event);
127 
128 	if (file) {
129 		if (perf_data_file__open(file))
130 			goto out_delete;
131 
132 		session->file = file;
133 
134 		if (perf_data_file__is_read(file)) {
135 			if (perf_session__open(session) < 0)
136 				goto out_close;
137 
138 			perf_session__set_id_hdr_size(session);
139 			perf_session__set_comm_exec(session);
140 		}
141 	}
142 
143 	if (!file || perf_data_file__is_write(file)) {
144 		/*
145 		 * In O_RDONLY mode this will be performed when reading the
146 		 * kernel MMAP event, in perf_event__process_mmap().
147 		 */
148 		if (perf_session__create_kernel_maps(session) < 0)
149 			pr_warning("Cannot read kernel map\n");
150 	}
151 
152 	if (tool && tool->ordering_requires_timestamps &&
153 	    tool->ordered_events && !perf_evlist__sample_id_all(session->evlist)) {
154 		dump_printf("WARNING: No sample_id_all support, falling back to unordered processing\n");
155 		tool->ordered_events = false;
156 	}
157 
158 	return session;
159 
160  out_close:
161 	perf_data_file__close(file);
162  out_delete:
163 	perf_session__delete(session);
164  out:
165 	return NULL;
166 }
167 
168 static void perf_session__delete_threads(struct perf_session *session)
169 {
170 	machine__delete_threads(&session->machines.host);
171 }
172 
173 static void perf_session_env__delete(struct perf_session_env *env)
174 {
175 	zfree(&env->hostname);
176 	zfree(&env->os_release);
177 	zfree(&env->version);
178 	zfree(&env->arch);
179 	zfree(&env->cpu_desc);
180 	zfree(&env->cpuid);
181 
182 	zfree(&env->cmdline);
183 	zfree(&env->cmdline_argv);
184 	zfree(&env->sibling_cores);
185 	zfree(&env->sibling_threads);
186 	zfree(&env->numa_nodes);
187 	zfree(&env->pmu_mappings);
188 }
189 
190 void perf_session__delete(struct perf_session *session)
191 {
192 	auxtrace__free(session);
193 	auxtrace_index__free(&session->auxtrace_index);
194 	perf_session__destroy_kernel_maps(session);
195 	perf_session__delete_threads(session);
196 	perf_session_env__delete(&session->header.env);
197 	machines__exit(&session->machines);
198 	if (session->file)
199 		perf_data_file__close(session->file);
200 	free(session);
201 }
202 
203 static int process_event_synth_tracing_data_stub(struct perf_tool *tool
204 						 __maybe_unused,
205 						 union perf_event *event
206 						 __maybe_unused,
207 						 struct perf_session *session
208 						__maybe_unused)
209 {
210 	dump_printf(": unhandled!\n");
211 	return 0;
212 }
213 
214 static int process_event_synth_attr_stub(struct perf_tool *tool __maybe_unused,
215 					 union perf_event *event __maybe_unused,
216 					 struct perf_evlist **pevlist
217 					 __maybe_unused)
218 {
219 	dump_printf(": unhandled!\n");
220 	return 0;
221 }
222 
223 static int process_event_sample_stub(struct perf_tool *tool __maybe_unused,
224 				     union perf_event *event __maybe_unused,
225 				     struct perf_sample *sample __maybe_unused,
226 				     struct perf_evsel *evsel __maybe_unused,
227 				     struct machine *machine __maybe_unused)
228 {
229 	dump_printf(": unhandled!\n");
230 	return 0;
231 }
232 
233 static int process_event_stub(struct perf_tool *tool __maybe_unused,
234 			      union perf_event *event __maybe_unused,
235 			      struct perf_sample *sample __maybe_unused,
236 			      struct machine *machine __maybe_unused)
237 {
238 	dump_printf(": unhandled!\n");
239 	return 0;
240 }
241 
242 static int process_build_id_stub(struct perf_tool *tool __maybe_unused,
243 				 union perf_event *event __maybe_unused,
244 				 struct perf_session *session __maybe_unused)
245 {
246 	dump_printf(": unhandled!\n");
247 	return 0;
248 }
249 
250 static int process_finished_round_stub(struct perf_tool *tool __maybe_unused,
251 				       union perf_event *event __maybe_unused,
252 				       struct ordered_events *oe __maybe_unused)
253 {
254 	dump_printf(": unhandled!\n");
255 	return 0;
256 }
257 
258 static int process_finished_round(struct perf_tool *tool,
259 				  union perf_event *event,
260 				  struct ordered_events *oe);
261 
262 static int process_id_index_stub(struct perf_tool *tool __maybe_unused,
263 				 union perf_event *event __maybe_unused,
264 				 struct perf_session *perf_session
265 				 __maybe_unused)
266 {
267 	dump_printf(": unhandled!\n");
268 	return 0;
269 }
270 
271 static int process_event_auxtrace_info_stub(struct perf_tool *tool __maybe_unused,
272 				union perf_event *event __maybe_unused,
273 				struct perf_session *session __maybe_unused)
274 {
275 	dump_printf(": unhandled!\n");
276 	return 0;
277 }
278 
279 static int skipn(int fd, off_t n)
280 {
281 	char buf[4096];
282 	ssize_t ret;
283 
284 	while (n > 0) {
285 		ret = read(fd, buf, min(n, (off_t)sizeof(buf)));
286 		if (ret <= 0)
287 			return ret;
288 		n -= ret;
289 	}
290 
291 	return 0;
292 }
293 
294 static s64 process_event_auxtrace_stub(struct perf_tool *tool __maybe_unused,
295 				       union perf_event *event,
296 				       struct perf_session *session
297 				       __maybe_unused)
298 {
299 	dump_printf(": unhandled!\n");
300 	if (perf_data_file__is_pipe(session->file))
301 		skipn(perf_data_file__fd(session->file), event->auxtrace.size);
302 	return event->auxtrace.size;
303 }
304 
305 static
306 int process_event_auxtrace_error_stub(struct perf_tool *tool __maybe_unused,
307 				      union perf_event *event __maybe_unused,
308 				      struct perf_session *session __maybe_unused)
309 {
310 	dump_printf(": unhandled!\n");
311 	return 0;
312 }
313 
314 void perf_tool__fill_defaults(struct perf_tool *tool)
315 {
316 	if (tool->sample == NULL)
317 		tool->sample = process_event_sample_stub;
318 	if (tool->mmap == NULL)
319 		tool->mmap = process_event_stub;
320 	if (tool->mmap2 == NULL)
321 		tool->mmap2 = process_event_stub;
322 	if (tool->comm == NULL)
323 		tool->comm = process_event_stub;
324 	if (tool->fork == NULL)
325 		tool->fork = process_event_stub;
326 	if (tool->exit == NULL)
327 		tool->exit = process_event_stub;
328 	if (tool->lost == NULL)
329 		tool->lost = perf_event__process_lost;
330 	if (tool->lost_samples == NULL)
331 		tool->lost_samples = perf_event__process_lost_samples;
332 	if (tool->aux == NULL)
333 		tool->aux = perf_event__process_aux;
334 	if (tool->itrace_start == NULL)
335 		tool->itrace_start = perf_event__process_itrace_start;
336 	if (tool->read == NULL)
337 		tool->read = process_event_sample_stub;
338 	if (tool->throttle == NULL)
339 		tool->throttle = process_event_stub;
340 	if (tool->unthrottle == NULL)
341 		tool->unthrottle = process_event_stub;
342 	if (tool->attr == NULL)
343 		tool->attr = process_event_synth_attr_stub;
344 	if (tool->tracing_data == NULL)
345 		tool->tracing_data = process_event_synth_tracing_data_stub;
346 	if (tool->build_id == NULL)
347 		tool->build_id = process_build_id_stub;
348 	if (tool->finished_round == NULL) {
349 		if (tool->ordered_events)
350 			tool->finished_round = process_finished_round;
351 		else
352 			tool->finished_round = process_finished_round_stub;
353 	}
354 	if (tool->id_index == NULL)
355 		tool->id_index = process_id_index_stub;
356 	if (tool->auxtrace_info == NULL)
357 		tool->auxtrace_info = process_event_auxtrace_info_stub;
358 	if (tool->auxtrace == NULL)
359 		tool->auxtrace = process_event_auxtrace_stub;
360 	if (tool->auxtrace_error == NULL)
361 		tool->auxtrace_error = process_event_auxtrace_error_stub;
362 }
363 
364 static void swap_sample_id_all(union perf_event *event, void *data)
365 {
366 	void *end = (void *) event + event->header.size;
367 	int size = end - data;
368 
369 	BUG_ON(size % sizeof(u64));
370 	mem_bswap_64(data, size);
371 }
372 
373 static void perf_event__all64_swap(union perf_event *event,
374 				   bool sample_id_all __maybe_unused)
375 {
376 	struct perf_event_header *hdr = &event->header;
377 	mem_bswap_64(hdr + 1, event->header.size - sizeof(*hdr));
378 }
379 
380 static void perf_event__comm_swap(union perf_event *event, bool sample_id_all)
381 {
382 	event->comm.pid = bswap_32(event->comm.pid);
383 	event->comm.tid = bswap_32(event->comm.tid);
384 
385 	if (sample_id_all) {
386 		void *data = &event->comm.comm;
387 
388 		data += PERF_ALIGN(strlen(data) + 1, sizeof(u64));
389 		swap_sample_id_all(event, data);
390 	}
391 }
392 
393 static void perf_event__mmap_swap(union perf_event *event,
394 				  bool sample_id_all)
395 {
396 	event->mmap.pid	  = bswap_32(event->mmap.pid);
397 	event->mmap.tid	  = bswap_32(event->mmap.tid);
398 	event->mmap.start = bswap_64(event->mmap.start);
399 	event->mmap.len	  = bswap_64(event->mmap.len);
400 	event->mmap.pgoff = bswap_64(event->mmap.pgoff);
401 
402 	if (sample_id_all) {
403 		void *data = &event->mmap.filename;
404 
405 		data += PERF_ALIGN(strlen(data) + 1, sizeof(u64));
406 		swap_sample_id_all(event, data);
407 	}
408 }
409 
410 static void perf_event__mmap2_swap(union perf_event *event,
411 				  bool sample_id_all)
412 {
413 	event->mmap2.pid   = bswap_32(event->mmap2.pid);
414 	event->mmap2.tid   = bswap_32(event->mmap2.tid);
415 	event->mmap2.start = bswap_64(event->mmap2.start);
416 	event->mmap2.len   = bswap_64(event->mmap2.len);
417 	event->mmap2.pgoff = bswap_64(event->mmap2.pgoff);
418 	event->mmap2.maj   = bswap_32(event->mmap2.maj);
419 	event->mmap2.min   = bswap_32(event->mmap2.min);
420 	event->mmap2.ino   = bswap_64(event->mmap2.ino);
421 
422 	if (sample_id_all) {
423 		void *data = &event->mmap2.filename;
424 
425 		data += PERF_ALIGN(strlen(data) + 1, sizeof(u64));
426 		swap_sample_id_all(event, data);
427 	}
428 }
429 static void perf_event__task_swap(union perf_event *event, bool sample_id_all)
430 {
431 	event->fork.pid	 = bswap_32(event->fork.pid);
432 	event->fork.tid	 = bswap_32(event->fork.tid);
433 	event->fork.ppid = bswap_32(event->fork.ppid);
434 	event->fork.ptid = bswap_32(event->fork.ptid);
435 	event->fork.time = bswap_64(event->fork.time);
436 
437 	if (sample_id_all)
438 		swap_sample_id_all(event, &event->fork + 1);
439 }
440 
441 static void perf_event__read_swap(union perf_event *event, bool sample_id_all)
442 {
443 	event->read.pid		 = bswap_32(event->read.pid);
444 	event->read.tid		 = bswap_32(event->read.tid);
445 	event->read.value	 = bswap_64(event->read.value);
446 	event->read.time_enabled = bswap_64(event->read.time_enabled);
447 	event->read.time_running = bswap_64(event->read.time_running);
448 	event->read.id		 = bswap_64(event->read.id);
449 
450 	if (sample_id_all)
451 		swap_sample_id_all(event, &event->read + 1);
452 }
453 
454 static void perf_event__aux_swap(union perf_event *event, bool sample_id_all)
455 {
456 	event->aux.aux_offset = bswap_64(event->aux.aux_offset);
457 	event->aux.aux_size   = bswap_64(event->aux.aux_size);
458 	event->aux.flags      = bswap_64(event->aux.flags);
459 
460 	if (sample_id_all)
461 		swap_sample_id_all(event, &event->aux + 1);
462 }
463 
464 static void perf_event__itrace_start_swap(union perf_event *event,
465 					  bool sample_id_all)
466 {
467 	event->itrace_start.pid	 = bswap_32(event->itrace_start.pid);
468 	event->itrace_start.tid	 = bswap_32(event->itrace_start.tid);
469 
470 	if (sample_id_all)
471 		swap_sample_id_all(event, &event->itrace_start + 1);
472 }
473 
474 static void perf_event__throttle_swap(union perf_event *event,
475 				      bool sample_id_all)
476 {
477 	event->throttle.time	  = bswap_64(event->throttle.time);
478 	event->throttle.id	  = bswap_64(event->throttle.id);
479 	event->throttle.stream_id = bswap_64(event->throttle.stream_id);
480 
481 	if (sample_id_all)
482 		swap_sample_id_all(event, &event->throttle + 1);
483 }
484 
485 static u8 revbyte(u8 b)
486 {
487 	int rev = (b >> 4) | ((b & 0xf) << 4);
488 	rev = ((rev & 0xcc) >> 2) | ((rev & 0x33) << 2);
489 	rev = ((rev & 0xaa) >> 1) | ((rev & 0x55) << 1);
490 	return (u8) rev;
491 }
492 
493 /*
494  * XXX this is hack in attempt to carry flags bitfield
495  * throught endian village. ABI says:
496  *
497  * Bit-fields are allocated from right to left (least to most significant)
498  * on little-endian implementations and from left to right (most to least
499  * significant) on big-endian implementations.
500  *
501  * The above seems to be byte specific, so we need to reverse each
502  * byte of the bitfield. 'Internet' also says this might be implementation
503  * specific and we probably need proper fix and carry perf_event_attr
504  * bitfield flags in separate data file FEAT_ section. Thought this seems
505  * to work for now.
506  */
507 static void swap_bitfield(u8 *p, unsigned len)
508 {
509 	unsigned i;
510 
511 	for (i = 0; i < len; i++) {
512 		*p = revbyte(*p);
513 		p++;
514 	}
515 }
516 
517 /* exported for swapping attributes in file header */
518 void perf_event__attr_swap(struct perf_event_attr *attr)
519 {
520 	attr->type		= bswap_32(attr->type);
521 	attr->size		= bswap_32(attr->size);
522 
523 #define bswap_safe(f, n) 					\
524 	(attr->size > (offsetof(struct perf_event_attr, f) + 	\
525 		       sizeof(attr->f) * (n)))
526 #define bswap_field(f, sz) 			\
527 do { 						\
528 	if (bswap_safe(f, 0))			\
529 		attr->f = bswap_##sz(attr->f);	\
530 } while(0)
531 #define bswap_field_32(f) bswap_field(f, 32)
532 #define bswap_field_64(f) bswap_field(f, 64)
533 
534 	bswap_field_64(config);
535 	bswap_field_64(sample_period);
536 	bswap_field_64(sample_type);
537 	bswap_field_64(read_format);
538 	bswap_field_32(wakeup_events);
539 	bswap_field_32(bp_type);
540 	bswap_field_64(bp_addr);
541 	bswap_field_64(bp_len);
542 	bswap_field_64(branch_sample_type);
543 	bswap_field_64(sample_regs_user);
544 	bswap_field_32(sample_stack_user);
545 	bswap_field_32(aux_watermark);
546 
547 	/*
548 	 * After read_format are bitfields. Check read_format because
549 	 * we are unable to use offsetof on bitfield.
550 	 */
551 	if (bswap_safe(read_format, 1))
552 		swap_bitfield((u8 *) (&attr->read_format + 1),
553 			      sizeof(u64));
554 #undef bswap_field_64
555 #undef bswap_field_32
556 #undef bswap_field
557 #undef bswap_safe
558 }
559 
560 static void perf_event__hdr_attr_swap(union perf_event *event,
561 				      bool sample_id_all __maybe_unused)
562 {
563 	size_t size;
564 
565 	perf_event__attr_swap(&event->attr.attr);
566 
567 	size = event->header.size;
568 	size -= (void *)&event->attr.id - (void *)event;
569 	mem_bswap_64(event->attr.id, size);
570 }
571 
572 static void perf_event__event_type_swap(union perf_event *event,
573 					bool sample_id_all __maybe_unused)
574 {
575 	event->event_type.event_type.event_id =
576 		bswap_64(event->event_type.event_type.event_id);
577 }
578 
579 static void perf_event__tracing_data_swap(union perf_event *event,
580 					  bool sample_id_all __maybe_unused)
581 {
582 	event->tracing_data.size = bswap_32(event->tracing_data.size);
583 }
584 
585 static void perf_event__auxtrace_info_swap(union perf_event *event,
586 					   bool sample_id_all __maybe_unused)
587 {
588 	size_t size;
589 
590 	event->auxtrace_info.type = bswap_32(event->auxtrace_info.type);
591 
592 	size = event->header.size;
593 	size -= (void *)&event->auxtrace_info.priv - (void *)event;
594 	mem_bswap_64(event->auxtrace_info.priv, size);
595 }
596 
597 static void perf_event__auxtrace_swap(union perf_event *event,
598 				      bool sample_id_all __maybe_unused)
599 {
600 	event->auxtrace.size      = bswap_64(event->auxtrace.size);
601 	event->auxtrace.offset    = bswap_64(event->auxtrace.offset);
602 	event->auxtrace.reference = bswap_64(event->auxtrace.reference);
603 	event->auxtrace.idx       = bswap_32(event->auxtrace.idx);
604 	event->auxtrace.tid       = bswap_32(event->auxtrace.tid);
605 	event->auxtrace.cpu       = bswap_32(event->auxtrace.cpu);
606 }
607 
608 static void perf_event__auxtrace_error_swap(union perf_event *event,
609 					    bool sample_id_all __maybe_unused)
610 {
611 	event->auxtrace_error.type = bswap_32(event->auxtrace_error.type);
612 	event->auxtrace_error.code = bswap_32(event->auxtrace_error.code);
613 	event->auxtrace_error.cpu  = bswap_32(event->auxtrace_error.cpu);
614 	event->auxtrace_error.pid  = bswap_32(event->auxtrace_error.pid);
615 	event->auxtrace_error.tid  = bswap_32(event->auxtrace_error.tid);
616 	event->auxtrace_error.ip   = bswap_64(event->auxtrace_error.ip);
617 }
618 
619 typedef void (*perf_event__swap_op)(union perf_event *event,
620 				    bool sample_id_all);
621 
622 static perf_event__swap_op perf_event__swap_ops[] = {
623 	[PERF_RECORD_MMAP]		  = perf_event__mmap_swap,
624 	[PERF_RECORD_MMAP2]		  = perf_event__mmap2_swap,
625 	[PERF_RECORD_COMM]		  = perf_event__comm_swap,
626 	[PERF_RECORD_FORK]		  = perf_event__task_swap,
627 	[PERF_RECORD_EXIT]		  = perf_event__task_swap,
628 	[PERF_RECORD_LOST]		  = perf_event__all64_swap,
629 	[PERF_RECORD_READ]		  = perf_event__read_swap,
630 	[PERF_RECORD_THROTTLE]		  = perf_event__throttle_swap,
631 	[PERF_RECORD_UNTHROTTLE]	  = perf_event__throttle_swap,
632 	[PERF_RECORD_SAMPLE]		  = perf_event__all64_swap,
633 	[PERF_RECORD_AUX]		  = perf_event__aux_swap,
634 	[PERF_RECORD_ITRACE_START]	  = perf_event__itrace_start_swap,
635 	[PERF_RECORD_LOST_SAMPLES]	  = perf_event__all64_swap,
636 	[PERF_RECORD_HEADER_ATTR]	  = perf_event__hdr_attr_swap,
637 	[PERF_RECORD_HEADER_EVENT_TYPE]	  = perf_event__event_type_swap,
638 	[PERF_RECORD_HEADER_TRACING_DATA] = perf_event__tracing_data_swap,
639 	[PERF_RECORD_HEADER_BUILD_ID]	  = NULL,
640 	[PERF_RECORD_ID_INDEX]		  = perf_event__all64_swap,
641 	[PERF_RECORD_AUXTRACE_INFO]	  = perf_event__auxtrace_info_swap,
642 	[PERF_RECORD_AUXTRACE]		  = perf_event__auxtrace_swap,
643 	[PERF_RECORD_AUXTRACE_ERROR]	  = perf_event__auxtrace_error_swap,
644 	[PERF_RECORD_HEADER_MAX]	  = NULL,
645 };
646 
647 /*
648  * When perf record finishes a pass on every buffers, it records this pseudo
649  * event.
650  * We record the max timestamp t found in the pass n.
651  * Assuming these timestamps are monotonic across cpus, we know that if
652  * a buffer still has events with timestamps below t, they will be all
653  * available and then read in the pass n + 1.
654  * Hence when we start to read the pass n + 2, we can safely flush every
655  * events with timestamps below t.
656  *
657  *    ============ PASS n =================
658  *       CPU 0         |   CPU 1
659  *                     |
660  *    cnt1 timestamps  |   cnt2 timestamps
661  *          1          |         2
662  *          2          |         3
663  *          -          |         4  <--- max recorded
664  *
665  *    ============ PASS n + 1 ==============
666  *       CPU 0         |   CPU 1
667  *                     |
668  *    cnt1 timestamps  |   cnt2 timestamps
669  *          3          |         5
670  *          4          |         6
671  *          5          |         7 <---- max recorded
672  *
673  *      Flush every events below timestamp 4
674  *
675  *    ============ PASS n + 2 ==============
676  *       CPU 0         |   CPU 1
677  *                     |
678  *    cnt1 timestamps  |   cnt2 timestamps
679  *          6          |         8
680  *          7          |         9
681  *          -          |         10
682  *
683  *      Flush every events below timestamp 7
684  *      etc...
685  */
686 static int process_finished_round(struct perf_tool *tool __maybe_unused,
687 				  union perf_event *event __maybe_unused,
688 				  struct ordered_events *oe)
689 {
690 	if (dump_trace)
691 		fprintf(stdout, "\n");
692 	return ordered_events__flush(oe, OE_FLUSH__ROUND);
693 }
694 
695 int perf_session__queue_event(struct perf_session *s, union perf_event *event,
696 			      struct perf_sample *sample, u64 file_offset)
697 {
698 	return ordered_events__queue(&s->ordered_events, event, sample, file_offset);
699 }
700 
701 static void callchain__lbr_callstack_printf(struct perf_sample *sample)
702 {
703 	struct ip_callchain *callchain = sample->callchain;
704 	struct branch_stack *lbr_stack = sample->branch_stack;
705 	u64 kernel_callchain_nr = callchain->nr;
706 	unsigned int i;
707 
708 	for (i = 0; i < kernel_callchain_nr; i++) {
709 		if (callchain->ips[i] == PERF_CONTEXT_USER)
710 			break;
711 	}
712 
713 	if ((i != kernel_callchain_nr) && lbr_stack->nr) {
714 		u64 total_nr;
715 		/*
716 		 * LBR callstack can only get user call chain,
717 		 * i is kernel call chain number,
718 		 * 1 is PERF_CONTEXT_USER.
719 		 *
720 		 * The user call chain is stored in LBR registers.
721 		 * LBR are pair registers. The caller is stored
722 		 * in "from" register, while the callee is stored
723 		 * in "to" register.
724 		 * For example, there is a call stack
725 		 * "A"->"B"->"C"->"D".
726 		 * The LBR registers will recorde like
727 		 * "C"->"D", "B"->"C", "A"->"B".
728 		 * So only the first "to" register and all "from"
729 		 * registers are needed to construct the whole stack.
730 		 */
731 		total_nr = i + 1 + lbr_stack->nr + 1;
732 		kernel_callchain_nr = i + 1;
733 
734 		printf("... LBR call chain: nr:%" PRIu64 "\n", total_nr);
735 
736 		for (i = 0; i < kernel_callchain_nr; i++)
737 			printf("..... %2d: %016" PRIx64 "\n",
738 			       i, callchain->ips[i]);
739 
740 		printf("..... %2d: %016" PRIx64 "\n",
741 		       (int)(kernel_callchain_nr), lbr_stack->entries[0].to);
742 		for (i = 0; i < lbr_stack->nr; i++)
743 			printf("..... %2d: %016" PRIx64 "\n",
744 			       (int)(i + kernel_callchain_nr + 1), lbr_stack->entries[i].from);
745 	}
746 }
747 
748 static void callchain__printf(struct perf_evsel *evsel,
749 			      struct perf_sample *sample)
750 {
751 	unsigned int i;
752 	struct ip_callchain *callchain = sample->callchain;
753 
754 	if (has_branch_callstack(evsel))
755 		callchain__lbr_callstack_printf(sample);
756 
757 	printf("... FP chain: nr:%" PRIu64 "\n", callchain->nr);
758 
759 	for (i = 0; i < callchain->nr; i++)
760 		printf("..... %2d: %016" PRIx64 "\n",
761 		       i, callchain->ips[i]);
762 }
763 
764 static void branch_stack__printf(struct perf_sample *sample)
765 {
766 	uint64_t i;
767 
768 	printf("... branch stack: nr:%" PRIu64 "\n", sample->branch_stack->nr);
769 
770 	for (i = 0; i < sample->branch_stack->nr; i++)
771 		printf("..... %2"PRIu64": %016" PRIx64 " -> %016" PRIx64 "\n",
772 			i, sample->branch_stack->entries[i].from,
773 			sample->branch_stack->entries[i].to);
774 }
775 
776 static void regs_dump__printf(u64 mask, u64 *regs)
777 {
778 	unsigned rid, i = 0;
779 
780 	for_each_set_bit(rid, (unsigned long *) &mask, sizeof(mask) * 8) {
781 		u64 val = regs[i++];
782 
783 		printf(".... %-5s 0x%" PRIx64 "\n",
784 		       perf_reg_name(rid), val);
785 	}
786 }
787 
788 static const char *regs_abi[] = {
789 	[PERF_SAMPLE_REGS_ABI_NONE] = "none",
790 	[PERF_SAMPLE_REGS_ABI_32] = "32-bit",
791 	[PERF_SAMPLE_REGS_ABI_64] = "64-bit",
792 };
793 
794 static inline const char *regs_dump_abi(struct regs_dump *d)
795 {
796 	if (d->abi > PERF_SAMPLE_REGS_ABI_64)
797 		return "unknown";
798 
799 	return regs_abi[d->abi];
800 }
801 
802 static void regs__printf(const char *type, struct regs_dump *regs)
803 {
804 	u64 mask = regs->mask;
805 
806 	printf("... %s regs: mask 0x%" PRIx64 " ABI %s\n",
807 	       type,
808 	       mask,
809 	       regs_dump_abi(regs));
810 
811 	regs_dump__printf(mask, regs->regs);
812 }
813 
814 static void regs_user__printf(struct perf_sample *sample)
815 {
816 	struct regs_dump *user_regs = &sample->user_regs;
817 
818 	if (user_regs->regs)
819 		regs__printf("user", user_regs);
820 }
821 
822 static void regs_intr__printf(struct perf_sample *sample)
823 {
824 	struct regs_dump *intr_regs = &sample->intr_regs;
825 
826 	if (intr_regs->regs)
827 		regs__printf("intr", intr_regs);
828 }
829 
830 static void stack_user__printf(struct stack_dump *dump)
831 {
832 	printf("... ustack: size %" PRIu64 ", offset 0x%x\n",
833 	       dump->size, dump->offset);
834 }
835 
836 static void perf_evlist__print_tstamp(struct perf_evlist *evlist,
837 				       union perf_event *event,
838 				       struct perf_sample *sample)
839 {
840 	u64 sample_type = __perf_evlist__combined_sample_type(evlist);
841 
842 	if (event->header.type != PERF_RECORD_SAMPLE &&
843 	    !perf_evlist__sample_id_all(evlist)) {
844 		fputs("-1 -1 ", stdout);
845 		return;
846 	}
847 
848 	if ((sample_type & PERF_SAMPLE_CPU))
849 		printf("%u ", sample->cpu);
850 
851 	if (sample_type & PERF_SAMPLE_TIME)
852 		printf("%" PRIu64 " ", sample->time);
853 }
854 
855 static void sample_read__printf(struct perf_sample *sample, u64 read_format)
856 {
857 	printf("... sample_read:\n");
858 
859 	if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED)
860 		printf("...... time enabled %016" PRIx64 "\n",
861 		       sample->read.time_enabled);
862 
863 	if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING)
864 		printf("...... time running %016" PRIx64 "\n",
865 		       sample->read.time_running);
866 
867 	if (read_format & PERF_FORMAT_GROUP) {
868 		u64 i;
869 
870 		printf(".... group nr %" PRIu64 "\n", sample->read.group.nr);
871 
872 		for (i = 0; i < sample->read.group.nr; i++) {
873 			struct sample_read_value *value;
874 
875 			value = &sample->read.group.values[i];
876 			printf("..... id %016" PRIx64
877 			       ", value %016" PRIx64 "\n",
878 			       value->id, value->value);
879 		}
880 	} else
881 		printf("..... id %016" PRIx64 ", value %016" PRIx64 "\n",
882 			sample->read.one.id, sample->read.one.value);
883 }
884 
885 static void dump_event(struct perf_evlist *evlist, union perf_event *event,
886 		       u64 file_offset, struct perf_sample *sample)
887 {
888 	if (!dump_trace)
889 		return;
890 
891 	printf("\n%#" PRIx64 " [%#x]: event: %d\n",
892 	       file_offset, event->header.size, event->header.type);
893 
894 	trace_event(event);
895 
896 	if (sample)
897 		perf_evlist__print_tstamp(evlist, event, sample);
898 
899 	printf("%#" PRIx64 " [%#x]: PERF_RECORD_%s", file_offset,
900 	       event->header.size, perf_event__name(event->header.type));
901 }
902 
903 static void dump_sample(struct perf_evsel *evsel, union perf_event *event,
904 			struct perf_sample *sample)
905 {
906 	u64 sample_type;
907 
908 	if (!dump_trace)
909 		return;
910 
911 	printf("(IP, 0x%x): %d/%d: %#" PRIx64 " period: %" PRIu64 " addr: %#" PRIx64 "\n",
912 	       event->header.misc, sample->pid, sample->tid, sample->ip,
913 	       sample->period, sample->addr);
914 
915 	sample_type = evsel->attr.sample_type;
916 
917 	if (sample_type & PERF_SAMPLE_CALLCHAIN)
918 		callchain__printf(evsel, sample);
919 
920 	if ((sample_type & PERF_SAMPLE_BRANCH_STACK) && !has_branch_callstack(evsel))
921 		branch_stack__printf(sample);
922 
923 	if (sample_type & PERF_SAMPLE_REGS_USER)
924 		regs_user__printf(sample);
925 
926 	if (sample_type & PERF_SAMPLE_REGS_INTR)
927 		regs_intr__printf(sample);
928 
929 	if (sample_type & PERF_SAMPLE_STACK_USER)
930 		stack_user__printf(&sample->user_stack);
931 
932 	if (sample_type & PERF_SAMPLE_WEIGHT)
933 		printf("... weight: %" PRIu64 "\n", sample->weight);
934 
935 	if (sample_type & PERF_SAMPLE_DATA_SRC)
936 		printf(" . data_src: 0x%"PRIx64"\n", sample->data_src);
937 
938 	if (sample_type & PERF_SAMPLE_TRANSACTION)
939 		printf("... transaction: %" PRIx64 "\n", sample->transaction);
940 
941 	if (sample_type & PERF_SAMPLE_READ)
942 		sample_read__printf(sample, evsel->attr.read_format);
943 }
944 
945 static struct machine *machines__find_for_cpumode(struct machines *machines,
946 					       union perf_event *event,
947 					       struct perf_sample *sample)
948 {
949 	const u8 cpumode = event->header.misc & PERF_RECORD_MISC_CPUMODE_MASK;
950 	struct machine *machine;
951 
952 	if (perf_guest &&
953 	    ((cpumode == PERF_RECORD_MISC_GUEST_KERNEL) ||
954 	     (cpumode == PERF_RECORD_MISC_GUEST_USER))) {
955 		u32 pid;
956 
957 		if (event->header.type == PERF_RECORD_MMAP
958 		    || event->header.type == PERF_RECORD_MMAP2)
959 			pid = event->mmap.pid;
960 		else
961 			pid = sample->pid;
962 
963 		machine = machines__find(machines, pid);
964 		if (!machine)
965 			machine = machines__find(machines, DEFAULT_GUEST_KERNEL_ID);
966 		return machine;
967 	}
968 
969 	return &machines->host;
970 }
971 
972 static int deliver_sample_value(struct perf_evlist *evlist,
973 				struct perf_tool *tool,
974 				union perf_event *event,
975 				struct perf_sample *sample,
976 				struct sample_read_value *v,
977 				struct machine *machine)
978 {
979 	struct perf_sample_id *sid = perf_evlist__id2sid(evlist, v->id);
980 
981 	if (sid) {
982 		sample->id     = v->id;
983 		sample->period = v->value - sid->period;
984 		sid->period    = v->value;
985 	}
986 
987 	if (!sid || sid->evsel == NULL) {
988 		++evlist->stats.nr_unknown_id;
989 		return 0;
990 	}
991 
992 	return tool->sample(tool, event, sample, sid->evsel, machine);
993 }
994 
995 static int deliver_sample_group(struct perf_evlist *evlist,
996 				struct perf_tool *tool,
997 				union  perf_event *event,
998 				struct perf_sample *sample,
999 				struct machine *machine)
1000 {
1001 	int ret = -EINVAL;
1002 	u64 i;
1003 
1004 	for (i = 0; i < sample->read.group.nr; i++) {
1005 		ret = deliver_sample_value(evlist, tool, event, sample,
1006 					   &sample->read.group.values[i],
1007 					   machine);
1008 		if (ret)
1009 			break;
1010 	}
1011 
1012 	return ret;
1013 }
1014 
1015 static int
1016  perf_evlist__deliver_sample(struct perf_evlist *evlist,
1017 			     struct perf_tool *tool,
1018 			     union  perf_event *event,
1019 			     struct perf_sample *sample,
1020 			     struct perf_evsel *evsel,
1021 			     struct machine *machine)
1022 {
1023 	/* We know evsel != NULL. */
1024 	u64 sample_type = evsel->attr.sample_type;
1025 	u64 read_format = evsel->attr.read_format;
1026 
1027 	/* Standard sample delievery. */
1028 	if (!(sample_type & PERF_SAMPLE_READ))
1029 		return tool->sample(tool, event, sample, evsel, machine);
1030 
1031 	/* For PERF_SAMPLE_READ we have either single or group mode. */
1032 	if (read_format & PERF_FORMAT_GROUP)
1033 		return deliver_sample_group(evlist, tool, event, sample,
1034 					    machine);
1035 	else
1036 		return deliver_sample_value(evlist, tool, event, sample,
1037 					    &sample->read.one, machine);
1038 }
1039 
1040 static int machines__deliver_event(struct machines *machines,
1041 				   struct perf_evlist *evlist,
1042 				   union perf_event *event,
1043 				   struct perf_sample *sample,
1044 				   struct perf_tool *tool, u64 file_offset)
1045 {
1046 	struct perf_evsel *evsel;
1047 	struct machine *machine;
1048 
1049 	dump_event(evlist, event, file_offset, sample);
1050 
1051 	evsel = perf_evlist__id2evsel(evlist, sample->id);
1052 
1053 	machine = machines__find_for_cpumode(machines, event, sample);
1054 
1055 	switch (event->header.type) {
1056 	case PERF_RECORD_SAMPLE:
1057 		dump_sample(evsel, event, sample);
1058 		if (evsel == NULL) {
1059 			++evlist->stats.nr_unknown_id;
1060 			return 0;
1061 		}
1062 		if (machine == NULL) {
1063 			++evlist->stats.nr_unprocessable_samples;
1064 			return 0;
1065 		}
1066 		return perf_evlist__deliver_sample(evlist, tool, event, sample, evsel, machine);
1067 	case PERF_RECORD_MMAP:
1068 		return tool->mmap(tool, event, sample, machine);
1069 	case PERF_RECORD_MMAP2:
1070 		if (event->header.misc & PERF_RECORD_MISC_PROC_MAP_PARSE_TIMEOUT)
1071 			++evlist->stats.nr_proc_map_timeout;
1072 		return tool->mmap2(tool, event, sample, machine);
1073 	case PERF_RECORD_COMM:
1074 		return tool->comm(tool, event, sample, machine);
1075 	case PERF_RECORD_FORK:
1076 		return tool->fork(tool, event, sample, machine);
1077 	case PERF_RECORD_EXIT:
1078 		return tool->exit(tool, event, sample, machine);
1079 	case PERF_RECORD_LOST:
1080 		if (tool->lost == perf_event__process_lost)
1081 			evlist->stats.total_lost += event->lost.lost;
1082 		return tool->lost(tool, event, sample, machine);
1083 	case PERF_RECORD_LOST_SAMPLES:
1084 		if (tool->lost_samples == perf_event__process_lost_samples)
1085 			evlist->stats.total_lost_samples += event->lost_samples.lost;
1086 		return tool->lost_samples(tool, event, sample, machine);
1087 	case PERF_RECORD_READ:
1088 		return tool->read(tool, event, sample, evsel, machine);
1089 	case PERF_RECORD_THROTTLE:
1090 		return tool->throttle(tool, event, sample, machine);
1091 	case PERF_RECORD_UNTHROTTLE:
1092 		return tool->unthrottle(tool, event, sample, machine);
1093 	case PERF_RECORD_AUX:
1094 		return tool->aux(tool, event, sample, machine);
1095 	case PERF_RECORD_ITRACE_START:
1096 		return tool->itrace_start(tool, event, sample, machine);
1097 	default:
1098 		++evlist->stats.nr_unknown_events;
1099 		return -1;
1100 	}
1101 }
1102 
1103 static int perf_session__deliver_event(struct perf_session *session,
1104 				       union perf_event *event,
1105 				       struct perf_sample *sample,
1106 				       struct perf_tool *tool,
1107 				       u64 file_offset)
1108 {
1109 	int ret;
1110 
1111 	ret = auxtrace__process_event(session, event, sample, tool);
1112 	if (ret < 0)
1113 		return ret;
1114 	if (ret > 0)
1115 		return 0;
1116 
1117 	return machines__deliver_event(&session->machines, session->evlist,
1118 				       event, sample, tool, file_offset);
1119 }
1120 
1121 static s64 perf_session__process_user_event(struct perf_session *session,
1122 					    union perf_event *event,
1123 					    u64 file_offset)
1124 {
1125 	struct ordered_events *oe = &session->ordered_events;
1126 	struct perf_tool *tool = session->tool;
1127 	int fd = perf_data_file__fd(session->file);
1128 	int err;
1129 
1130 	dump_event(session->evlist, event, file_offset, NULL);
1131 
1132 	/* These events are processed right away */
1133 	switch (event->header.type) {
1134 	case PERF_RECORD_HEADER_ATTR:
1135 		err = tool->attr(tool, event, &session->evlist);
1136 		if (err == 0) {
1137 			perf_session__set_id_hdr_size(session);
1138 			perf_session__set_comm_exec(session);
1139 		}
1140 		return err;
1141 	case PERF_RECORD_HEADER_EVENT_TYPE:
1142 		/*
1143 		 * Depreceated, but we need to handle it for sake
1144 		 * of old data files create in pipe mode.
1145 		 */
1146 		return 0;
1147 	case PERF_RECORD_HEADER_TRACING_DATA:
1148 		/* setup for reading amidst mmap */
1149 		lseek(fd, file_offset, SEEK_SET);
1150 		return tool->tracing_data(tool, event, session);
1151 	case PERF_RECORD_HEADER_BUILD_ID:
1152 		return tool->build_id(tool, event, session);
1153 	case PERF_RECORD_FINISHED_ROUND:
1154 		return tool->finished_round(tool, event, oe);
1155 	case PERF_RECORD_ID_INDEX:
1156 		return tool->id_index(tool, event, session);
1157 	case PERF_RECORD_AUXTRACE_INFO:
1158 		return tool->auxtrace_info(tool, event, session);
1159 	case PERF_RECORD_AUXTRACE:
1160 		/* setup for reading amidst mmap */
1161 		lseek(fd, file_offset + event->header.size, SEEK_SET);
1162 		return tool->auxtrace(tool, event, session);
1163 	case PERF_RECORD_AUXTRACE_ERROR:
1164 		perf_session__auxtrace_error_inc(session, event);
1165 		return tool->auxtrace_error(tool, event, session);
1166 	default:
1167 		return -EINVAL;
1168 	}
1169 }
1170 
1171 int perf_session__deliver_synth_event(struct perf_session *session,
1172 				      union perf_event *event,
1173 				      struct perf_sample *sample)
1174 {
1175 	struct perf_evlist *evlist = session->evlist;
1176 	struct perf_tool *tool = session->tool;
1177 
1178 	events_stats__inc(&evlist->stats, event->header.type);
1179 
1180 	if (event->header.type >= PERF_RECORD_USER_TYPE_START)
1181 		return perf_session__process_user_event(session, event, 0);
1182 
1183 	return machines__deliver_event(&session->machines, evlist, event, sample, tool, 0);
1184 }
1185 
1186 static void event_swap(union perf_event *event, bool sample_id_all)
1187 {
1188 	perf_event__swap_op swap;
1189 
1190 	swap = perf_event__swap_ops[event->header.type];
1191 	if (swap)
1192 		swap(event, sample_id_all);
1193 }
1194 
1195 int perf_session__peek_event(struct perf_session *session, off_t file_offset,
1196 			     void *buf, size_t buf_sz,
1197 			     union perf_event **event_ptr,
1198 			     struct perf_sample *sample)
1199 {
1200 	union perf_event *event;
1201 	size_t hdr_sz, rest;
1202 	int fd;
1203 
1204 	if (session->one_mmap && !session->header.needs_swap) {
1205 		event = file_offset - session->one_mmap_offset +
1206 			session->one_mmap_addr;
1207 		goto out_parse_sample;
1208 	}
1209 
1210 	if (perf_data_file__is_pipe(session->file))
1211 		return -1;
1212 
1213 	fd = perf_data_file__fd(session->file);
1214 	hdr_sz = sizeof(struct perf_event_header);
1215 
1216 	if (buf_sz < hdr_sz)
1217 		return -1;
1218 
1219 	if (lseek(fd, file_offset, SEEK_SET) == (off_t)-1 ||
1220 	    readn(fd, buf, hdr_sz) != (ssize_t)hdr_sz)
1221 		return -1;
1222 
1223 	event = (union perf_event *)buf;
1224 
1225 	if (session->header.needs_swap)
1226 		perf_event_header__bswap(&event->header);
1227 
1228 	if (event->header.size < hdr_sz || event->header.size > buf_sz)
1229 		return -1;
1230 
1231 	rest = event->header.size - hdr_sz;
1232 
1233 	if (readn(fd, buf, rest) != (ssize_t)rest)
1234 		return -1;
1235 
1236 	if (session->header.needs_swap)
1237 		event_swap(event, perf_evlist__sample_id_all(session->evlist));
1238 
1239 out_parse_sample:
1240 
1241 	if (sample && event->header.type < PERF_RECORD_USER_TYPE_START &&
1242 	    perf_evlist__parse_sample(session->evlist, event, sample))
1243 		return -1;
1244 
1245 	*event_ptr = event;
1246 
1247 	return 0;
1248 }
1249 
1250 static s64 perf_session__process_event(struct perf_session *session,
1251 				       union perf_event *event, u64 file_offset)
1252 {
1253 	struct perf_evlist *evlist = session->evlist;
1254 	struct perf_tool *tool = session->tool;
1255 	struct perf_sample sample;
1256 	int ret;
1257 
1258 	if (session->header.needs_swap)
1259 		event_swap(event, perf_evlist__sample_id_all(evlist));
1260 
1261 	if (event->header.type >= PERF_RECORD_HEADER_MAX)
1262 		return -EINVAL;
1263 
1264 	events_stats__inc(&evlist->stats, event->header.type);
1265 
1266 	if (event->header.type >= PERF_RECORD_USER_TYPE_START)
1267 		return perf_session__process_user_event(session, event, file_offset);
1268 
1269 	/*
1270 	 * For all kernel events we get the sample data
1271 	 */
1272 	ret = perf_evlist__parse_sample(evlist, event, &sample);
1273 	if (ret)
1274 		return ret;
1275 
1276 	if (tool->ordered_events) {
1277 		ret = perf_session__queue_event(session, event, &sample, file_offset);
1278 		if (ret != -ETIME)
1279 			return ret;
1280 	}
1281 
1282 	return perf_session__deliver_event(session, event, &sample, tool,
1283 					   file_offset);
1284 }
1285 
1286 void perf_event_header__bswap(struct perf_event_header *hdr)
1287 {
1288 	hdr->type = bswap_32(hdr->type);
1289 	hdr->misc = bswap_16(hdr->misc);
1290 	hdr->size = bswap_16(hdr->size);
1291 }
1292 
1293 struct thread *perf_session__findnew(struct perf_session *session, pid_t pid)
1294 {
1295 	return machine__findnew_thread(&session->machines.host, -1, pid);
1296 }
1297 
1298 static struct thread *perf_session__register_idle_thread(struct perf_session *session)
1299 {
1300 	struct thread *thread;
1301 
1302 	thread = machine__findnew_thread(&session->machines.host, 0, 0);
1303 	if (thread == NULL || thread__set_comm(thread, "swapper", 0)) {
1304 		pr_err("problem inserting idle task.\n");
1305 		thread = NULL;
1306 	}
1307 
1308 	return thread;
1309 }
1310 
1311 static void perf_session__warn_about_errors(const struct perf_session *session)
1312 {
1313 	const struct events_stats *stats = &session->evlist->stats;
1314 	const struct ordered_events *oe = &session->ordered_events;
1315 
1316 	if (session->tool->lost == perf_event__process_lost &&
1317 	    stats->nr_events[PERF_RECORD_LOST] != 0) {
1318 		ui__warning("Processed %d events and lost %d chunks!\n\n"
1319 			    "Check IO/CPU overload!\n\n",
1320 			    stats->nr_events[0],
1321 			    stats->nr_events[PERF_RECORD_LOST]);
1322 	}
1323 
1324 	if (session->tool->lost_samples == perf_event__process_lost_samples) {
1325 		double drop_rate;
1326 
1327 		drop_rate = (double)stats->total_lost_samples /
1328 			    (double) (stats->nr_events[PERF_RECORD_SAMPLE] + stats->total_lost_samples);
1329 		if (drop_rate > 0.05) {
1330 			ui__warning("Processed %" PRIu64 " samples and lost %3.2f%% samples!\n\n",
1331 				    stats->nr_events[PERF_RECORD_SAMPLE] + stats->total_lost_samples,
1332 				    drop_rate * 100.0);
1333 		}
1334 	}
1335 
1336 	if (stats->nr_unknown_events != 0) {
1337 		ui__warning("Found %u unknown events!\n\n"
1338 			    "Is this an older tool processing a perf.data "
1339 			    "file generated by a more recent tool?\n\n"
1340 			    "If that is not the case, consider "
1341 			    "reporting to linux-kernel@vger.kernel.org.\n\n",
1342 			    stats->nr_unknown_events);
1343 	}
1344 
1345 	if (stats->nr_unknown_id != 0) {
1346 		ui__warning("%u samples with id not present in the header\n",
1347 			    stats->nr_unknown_id);
1348 	}
1349 
1350 	if (stats->nr_invalid_chains != 0) {
1351 		ui__warning("Found invalid callchains!\n\n"
1352 			    "%u out of %u events were discarded for this reason.\n\n"
1353 			    "Consider reporting to linux-kernel@vger.kernel.org.\n\n",
1354 			    stats->nr_invalid_chains,
1355 			    stats->nr_events[PERF_RECORD_SAMPLE]);
1356 	}
1357 
1358 	if (stats->nr_unprocessable_samples != 0) {
1359 		ui__warning("%u unprocessable samples recorded.\n"
1360 			    "Do you have a KVM guest running and not using 'perf kvm'?\n",
1361 			    stats->nr_unprocessable_samples);
1362 	}
1363 
1364 	if (oe->nr_unordered_events != 0)
1365 		ui__warning("%u out of order events recorded.\n", oe->nr_unordered_events);
1366 
1367 	events_stats__auxtrace_error_warn(stats);
1368 
1369 	if (stats->nr_proc_map_timeout != 0) {
1370 		ui__warning("%d map information files for pre-existing threads were\n"
1371 			    "not processed, if there are samples for addresses they\n"
1372 			    "will not be resolved, you may find out which are these\n"
1373 			    "threads by running with -v and redirecting the output\n"
1374 			    "to a file.\n"
1375 			    "The time limit to process proc map is too short?\n"
1376 			    "Increase it by --proc-map-timeout\n",
1377 			    stats->nr_proc_map_timeout);
1378 	}
1379 }
1380 
1381 static int perf_session__flush_thread_stack(struct thread *thread,
1382 					    void *p __maybe_unused)
1383 {
1384 	return thread_stack__flush(thread);
1385 }
1386 
1387 static int perf_session__flush_thread_stacks(struct perf_session *session)
1388 {
1389 	return machines__for_each_thread(&session->machines,
1390 					 perf_session__flush_thread_stack,
1391 					 NULL);
1392 }
1393 
1394 volatile int session_done;
1395 
1396 static int __perf_session__process_pipe_events(struct perf_session *session)
1397 {
1398 	struct ordered_events *oe = &session->ordered_events;
1399 	struct perf_tool *tool = session->tool;
1400 	int fd = perf_data_file__fd(session->file);
1401 	union perf_event *event;
1402 	uint32_t size, cur_size = 0;
1403 	void *buf = NULL;
1404 	s64 skip = 0;
1405 	u64 head;
1406 	ssize_t err;
1407 	void *p;
1408 
1409 	perf_tool__fill_defaults(tool);
1410 
1411 	head = 0;
1412 	cur_size = sizeof(union perf_event);
1413 
1414 	buf = malloc(cur_size);
1415 	if (!buf)
1416 		return -errno;
1417 more:
1418 	event = buf;
1419 	err = readn(fd, event, sizeof(struct perf_event_header));
1420 	if (err <= 0) {
1421 		if (err == 0)
1422 			goto done;
1423 
1424 		pr_err("failed to read event header\n");
1425 		goto out_err;
1426 	}
1427 
1428 	if (session->header.needs_swap)
1429 		perf_event_header__bswap(&event->header);
1430 
1431 	size = event->header.size;
1432 	if (size < sizeof(struct perf_event_header)) {
1433 		pr_err("bad event header size\n");
1434 		goto out_err;
1435 	}
1436 
1437 	if (size > cur_size) {
1438 		void *new = realloc(buf, size);
1439 		if (!new) {
1440 			pr_err("failed to allocate memory to read event\n");
1441 			goto out_err;
1442 		}
1443 		buf = new;
1444 		cur_size = size;
1445 		event = buf;
1446 	}
1447 	p = event;
1448 	p += sizeof(struct perf_event_header);
1449 
1450 	if (size - sizeof(struct perf_event_header)) {
1451 		err = readn(fd, p, size - sizeof(struct perf_event_header));
1452 		if (err <= 0) {
1453 			if (err == 0) {
1454 				pr_err("unexpected end of event stream\n");
1455 				goto done;
1456 			}
1457 
1458 			pr_err("failed to read event data\n");
1459 			goto out_err;
1460 		}
1461 	}
1462 
1463 	if ((skip = perf_session__process_event(session, event, head)) < 0) {
1464 		pr_err("%#" PRIx64 " [%#x]: failed to process type: %d\n",
1465 		       head, event->header.size, event->header.type);
1466 		err = -EINVAL;
1467 		goto out_err;
1468 	}
1469 
1470 	head += size;
1471 
1472 	if (skip > 0)
1473 		head += skip;
1474 
1475 	if (!session_done())
1476 		goto more;
1477 done:
1478 	/* do the final flush for ordered samples */
1479 	err = ordered_events__flush(oe, OE_FLUSH__FINAL);
1480 	if (err)
1481 		goto out_err;
1482 	err = auxtrace__flush_events(session, tool);
1483 	if (err)
1484 		goto out_err;
1485 	err = perf_session__flush_thread_stacks(session);
1486 out_err:
1487 	free(buf);
1488 	perf_session__warn_about_errors(session);
1489 	ordered_events__free(&session->ordered_events);
1490 	auxtrace__free_events(session);
1491 	return err;
1492 }
1493 
1494 static union perf_event *
1495 fetch_mmaped_event(struct perf_session *session,
1496 		   u64 head, size_t mmap_size, char *buf)
1497 {
1498 	union perf_event *event;
1499 
1500 	/*
1501 	 * Ensure we have enough space remaining to read
1502 	 * the size of the event in the headers.
1503 	 */
1504 	if (head + sizeof(event->header) > mmap_size)
1505 		return NULL;
1506 
1507 	event = (union perf_event *)(buf + head);
1508 
1509 	if (session->header.needs_swap)
1510 		perf_event_header__bswap(&event->header);
1511 
1512 	if (head + event->header.size > mmap_size) {
1513 		/* We're not fetching the event so swap back again */
1514 		if (session->header.needs_swap)
1515 			perf_event_header__bswap(&event->header);
1516 		return NULL;
1517 	}
1518 
1519 	return event;
1520 }
1521 
1522 /*
1523  * On 64bit we can mmap the data file in one go. No need for tiny mmap
1524  * slices. On 32bit we use 32MB.
1525  */
1526 #if BITS_PER_LONG == 64
1527 #define MMAP_SIZE ULLONG_MAX
1528 #define NUM_MMAPS 1
1529 #else
1530 #define MMAP_SIZE (32 * 1024 * 1024ULL)
1531 #define NUM_MMAPS 128
1532 #endif
1533 
1534 static int __perf_session__process_events(struct perf_session *session,
1535 					  u64 data_offset, u64 data_size,
1536 					  u64 file_size)
1537 {
1538 	struct ordered_events *oe = &session->ordered_events;
1539 	struct perf_tool *tool = session->tool;
1540 	int fd = perf_data_file__fd(session->file);
1541 	u64 head, page_offset, file_offset, file_pos, size;
1542 	int err, mmap_prot, mmap_flags, map_idx = 0;
1543 	size_t	mmap_size;
1544 	char *buf, *mmaps[NUM_MMAPS];
1545 	union perf_event *event;
1546 	struct ui_progress prog;
1547 	s64 skip;
1548 
1549 	perf_tool__fill_defaults(tool);
1550 
1551 	page_offset = page_size * (data_offset / page_size);
1552 	file_offset = page_offset;
1553 	head = data_offset - page_offset;
1554 
1555 	if (data_size && (data_offset + data_size < file_size))
1556 		file_size = data_offset + data_size;
1557 
1558 	ui_progress__init(&prog, file_size, "Processing events...");
1559 
1560 	mmap_size = MMAP_SIZE;
1561 	if (mmap_size > file_size) {
1562 		mmap_size = file_size;
1563 		session->one_mmap = true;
1564 	}
1565 
1566 	memset(mmaps, 0, sizeof(mmaps));
1567 
1568 	mmap_prot  = PROT_READ;
1569 	mmap_flags = MAP_SHARED;
1570 
1571 	if (session->header.needs_swap) {
1572 		mmap_prot  |= PROT_WRITE;
1573 		mmap_flags = MAP_PRIVATE;
1574 	}
1575 remap:
1576 	buf = mmap(NULL, mmap_size, mmap_prot, mmap_flags, fd,
1577 		   file_offset);
1578 	if (buf == MAP_FAILED) {
1579 		pr_err("failed to mmap file\n");
1580 		err = -errno;
1581 		goto out_err;
1582 	}
1583 	mmaps[map_idx] = buf;
1584 	map_idx = (map_idx + 1) & (ARRAY_SIZE(mmaps) - 1);
1585 	file_pos = file_offset + head;
1586 	if (session->one_mmap) {
1587 		session->one_mmap_addr = buf;
1588 		session->one_mmap_offset = file_offset;
1589 	}
1590 
1591 more:
1592 	event = fetch_mmaped_event(session, head, mmap_size, buf);
1593 	if (!event) {
1594 		if (mmaps[map_idx]) {
1595 			munmap(mmaps[map_idx], mmap_size);
1596 			mmaps[map_idx] = NULL;
1597 		}
1598 
1599 		page_offset = page_size * (head / page_size);
1600 		file_offset += page_offset;
1601 		head -= page_offset;
1602 		goto remap;
1603 	}
1604 
1605 	size = event->header.size;
1606 
1607 	if (size < sizeof(struct perf_event_header) ||
1608 	    (skip = perf_session__process_event(session, event, file_pos)) < 0) {
1609 		pr_err("%#" PRIx64 " [%#x]: failed to process type: %d\n",
1610 		       file_offset + head, event->header.size,
1611 		       event->header.type);
1612 		err = -EINVAL;
1613 		goto out_err;
1614 	}
1615 
1616 	if (skip)
1617 		size += skip;
1618 
1619 	head += size;
1620 	file_pos += size;
1621 
1622 	ui_progress__update(&prog, size);
1623 
1624 	if (session_done())
1625 		goto out;
1626 
1627 	if (file_pos < file_size)
1628 		goto more;
1629 
1630 out:
1631 	/* do the final flush for ordered samples */
1632 	err = ordered_events__flush(oe, OE_FLUSH__FINAL);
1633 	if (err)
1634 		goto out_err;
1635 	err = auxtrace__flush_events(session, tool);
1636 	if (err)
1637 		goto out_err;
1638 	err = perf_session__flush_thread_stacks(session);
1639 out_err:
1640 	ui_progress__finish();
1641 	perf_session__warn_about_errors(session);
1642 	ordered_events__free(&session->ordered_events);
1643 	auxtrace__free_events(session);
1644 	session->one_mmap = false;
1645 	return err;
1646 }
1647 
1648 int perf_session__process_events(struct perf_session *session)
1649 {
1650 	u64 size = perf_data_file__size(session->file);
1651 	int err;
1652 
1653 	if (perf_session__register_idle_thread(session) == NULL)
1654 		return -ENOMEM;
1655 
1656 	if (!perf_data_file__is_pipe(session->file))
1657 		err = __perf_session__process_events(session,
1658 						     session->header.data_offset,
1659 						     session->header.data_size, size);
1660 	else
1661 		err = __perf_session__process_pipe_events(session);
1662 
1663 	return err;
1664 }
1665 
1666 bool perf_session__has_traces(struct perf_session *session, const char *msg)
1667 {
1668 	struct perf_evsel *evsel;
1669 
1670 	evlist__for_each(session->evlist, evsel) {
1671 		if (evsel->attr.type == PERF_TYPE_TRACEPOINT)
1672 			return true;
1673 	}
1674 
1675 	pr_err("No trace sample to read. Did you call 'perf %s'?\n", msg);
1676 	return false;
1677 }
1678 
1679 int maps__set_kallsyms_ref_reloc_sym(struct map **maps,
1680 				     const char *symbol_name, u64 addr)
1681 {
1682 	char *bracket;
1683 	enum map_type i;
1684 	struct ref_reloc_sym *ref;
1685 
1686 	ref = zalloc(sizeof(struct ref_reloc_sym));
1687 	if (ref == NULL)
1688 		return -ENOMEM;
1689 
1690 	ref->name = strdup(symbol_name);
1691 	if (ref->name == NULL) {
1692 		free(ref);
1693 		return -ENOMEM;
1694 	}
1695 
1696 	bracket = strchr(ref->name, ']');
1697 	if (bracket)
1698 		*bracket = '\0';
1699 
1700 	ref->addr = addr;
1701 
1702 	for (i = 0; i < MAP__NR_TYPES; ++i) {
1703 		struct kmap *kmap = map__kmap(maps[i]);
1704 
1705 		if (!kmap)
1706 			continue;
1707 		kmap->ref_reloc_sym = ref;
1708 	}
1709 
1710 	return 0;
1711 }
1712 
1713 size_t perf_session__fprintf_dsos(struct perf_session *session, FILE *fp)
1714 {
1715 	return machines__fprintf_dsos(&session->machines, fp);
1716 }
1717 
1718 size_t perf_session__fprintf_dsos_buildid(struct perf_session *session, FILE *fp,
1719 					  bool (skip)(struct dso *dso, int parm), int parm)
1720 {
1721 	return machines__fprintf_dsos_buildid(&session->machines, fp, skip, parm);
1722 }
1723 
1724 size_t perf_session__fprintf_nr_events(struct perf_session *session, FILE *fp)
1725 {
1726 	size_t ret;
1727 	const char *msg = "";
1728 
1729 	if (perf_header__has_feat(&session->header, HEADER_AUXTRACE))
1730 		msg = " (excludes AUX area (e.g. instruction trace) decoded / synthesized events)";
1731 
1732 	ret = fprintf(fp, "\nAggregated stats:%s\n", msg);
1733 
1734 	ret += events_stats__fprintf(&session->evlist->stats, fp);
1735 	return ret;
1736 }
1737 
1738 size_t perf_session__fprintf(struct perf_session *session, FILE *fp)
1739 {
1740 	/*
1741 	 * FIXME: Here we have to actually print all the machines in this
1742 	 * session, not just the host...
1743 	 */
1744 	return machine__fprintf(&session->machines.host, fp);
1745 }
1746 
1747 struct perf_evsel *perf_session__find_first_evtype(struct perf_session *session,
1748 					      unsigned int type)
1749 {
1750 	struct perf_evsel *pos;
1751 
1752 	evlist__for_each(session->evlist, pos) {
1753 		if (pos->attr.type == type)
1754 			return pos;
1755 	}
1756 	return NULL;
1757 }
1758 
1759 void perf_evsel__print_ip(struct perf_evsel *evsel, struct perf_sample *sample,
1760 			  struct addr_location *al,
1761 			  unsigned int print_opts, unsigned int stack_depth)
1762 {
1763 	struct callchain_cursor_node *node;
1764 	int print_ip = print_opts & PRINT_IP_OPT_IP;
1765 	int print_sym = print_opts & PRINT_IP_OPT_SYM;
1766 	int print_dso = print_opts & PRINT_IP_OPT_DSO;
1767 	int print_symoffset = print_opts & PRINT_IP_OPT_SYMOFFSET;
1768 	int print_oneline = print_opts & PRINT_IP_OPT_ONELINE;
1769 	int print_srcline = print_opts & PRINT_IP_OPT_SRCLINE;
1770 	char s = print_oneline ? ' ' : '\t';
1771 
1772 	if (symbol_conf.use_callchain && sample->callchain) {
1773 		struct addr_location node_al;
1774 
1775 		if (thread__resolve_callchain(al->thread, evsel,
1776 					      sample, NULL, NULL,
1777 					      PERF_MAX_STACK_DEPTH) != 0) {
1778 			if (verbose)
1779 				error("Failed to resolve callchain. Skipping\n");
1780 			return;
1781 		}
1782 		callchain_cursor_commit(&callchain_cursor);
1783 
1784 		if (print_symoffset)
1785 			node_al = *al;
1786 
1787 		while (stack_depth) {
1788 			u64 addr = 0;
1789 
1790 			node = callchain_cursor_current(&callchain_cursor);
1791 			if (!node)
1792 				break;
1793 
1794 			if (node->sym && node->sym->ignore)
1795 				goto next;
1796 
1797 			if (print_ip)
1798 				printf("%c%16" PRIx64, s, node->ip);
1799 
1800 			if (node->map)
1801 				addr = node->map->map_ip(node->map, node->ip);
1802 
1803 			if (print_sym) {
1804 				printf(" ");
1805 				if (print_symoffset) {
1806 					node_al.addr = addr;
1807 					node_al.map  = node->map;
1808 					symbol__fprintf_symname_offs(node->sym, &node_al, stdout);
1809 				} else
1810 					symbol__fprintf_symname(node->sym, stdout);
1811 			}
1812 
1813 			if (print_dso) {
1814 				printf(" (");
1815 				map__fprintf_dsoname(node->map, stdout);
1816 				printf(")");
1817 			}
1818 
1819 			if (print_srcline)
1820 				map__fprintf_srcline(node->map, addr, "\n  ",
1821 						     stdout);
1822 
1823 			if (!print_oneline)
1824 				printf("\n");
1825 
1826 			stack_depth--;
1827 next:
1828 			callchain_cursor_advance(&callchain_cursor);
1829 		}
1830 
1831 	} else {
1832 		if (al->sym && al->sym->ignore)
1833 			return;
1834 
1835 		if (print_ip)
1836 			printf("%16" PRIx64, sample->ip);
1837 
1838 		if (print_sym) {
1839 			printf(" ");
1840 			if (print_symoffset)
1841 				symbol__fprintf_symname_offs(al->sym, al,
1842 							     stdout);
1843 			else
1844 				symbol__fprintf_symname(al->sym, stdout);
1845 		}
1846 
1847 		if (print_dso) {
1848 			printf(" (");
1849 			map__fprintf_dsoname(al->map, stdout);
1850 			printf(")");
1851 		}
1852 
1853 		if (print_srcline)
1854 			map__fprintf_srcline(al->map, al->addr, "\n  ", stdout);
1855 	}
1856 }
1857 
1858 int perf_session__cpu_bitmap(struct perf_session *session,
1859 			     const char *cpu_list, unsigned long *cpu_bitmap)
1860 {
1861 	int i, err = -1;
1862 	struct cpu_map *map;
1863 
1864 	for (i = 0; i < PERF_TYPE_MAX; ++i) {
1865 		struct perf_evsel *evsel;
1866 
1867 		evsel = perf_session__find_first_evtype(session, i);
1868 		if (!evsel)
1869 			continue;
1870 
1871 		if (!(evsel->attr.sample_type & PERF_SAMPLE_CPU)) {
1872 			pr_err("File does not contain CPU events. "
1873 			       "Remove -c option to proceed.\n");
1874 			return -1;
1875 		}
1876 	}
1877 
1878 	map = cpu_map__new(cpu_list);
1879 	if (map == NULL) {
1880 		pr_err("Invalid cpu_list\n");
1881 		return -1;
1882 	}
1883 
1884 	for (i = 0; i < map->nr; i++) {
1885 		int cpu = map->map[i];
1886 
1887 		if (cpu >= MAX_NR_CPUS) {
1888 			pr_err("Requested CPU %d too large. "
1889 			       "Consider raising MAX_NR_CPUS\n", cpu);
1890 			goto out_delete_map;
1891 		}
1892 
1893 		set_bit(cpu, cpu_bitmap);
1894 	}
1895 
1896 	err = 0;
1897 
1898 out_delete_map:
1899 	cpu_map__put(map);
1900 	return err;
1901 }
1902 
1903 void perf_session__fprintf_info(struct perf_session *session, FILE *fp,
1904 				bool full)
1905 {
1906 	struct stat st;
1907 	int fd, ret;
1908 
1909 	if (session == NULL || fp == NULL)
1910 		return;
1911 
1912 	fd = perf_data_file__fd(session->file);
1913 
1914 	ret = fstat(fd, &st);
1915 	if (ret == -1)
1916 		return;
1917 
1918 	fprintf(fp, "# ========\n");
1919 	fprintf(fp, "# captured on: %s", ctime(&st.st_ctime));
1920 	perf_header__fprintf_info(session, fp, full);
1921 	fprintf(fp, "# ========\n#\n");
1922 }
1923 
1924 
1925 int __perf_session__set_tracepoints_handlers(struct perf_session *session,
1926 					     const struct perf_evsel_str_handler *assocs,
1927 					     size_t nr_assocs)
1928 {
1929 	struct perf_evsel *evsel;
1930 	size_t i;
1931 	int err;
1932 
1933 	for (i = 0; i < nr_assocs; i++) {
1934 		/*
1935 		 * Adding a handler for an event not in the session,
1936 		 * just ignore it.
1937 		 */
1938 		evsel = perf_evlist__find_tracepoint_by_name(session->evlist, assocs[i].name);
1939 		if (evsel == NULL)
1940 			continue;
1941 
1942 		err = -EEXIST;
1943 		if (evsel->handler != NULL)
1944 			goto out;
1945 		evsel->handler = assocs[i].handler;
1946 	}
1947 
1948 	err = 0;
1949 out:
1950 	return err;
1951 }
1952 
1953 int perf_event__process_id_index(struct perf_tool *tool __maybe_unused,
1954 				 union perf_event *event,
1955 				 struct perf_session *session)
1956 {
1957 	struct perf_evlist *evlist = session->evlist;
1958 	struct id_index_event *ie = &event->id_index;
1959 	size_t i, nr, max_nr;
1960 
1961 	max_nr = (ie->header.size - sizeof(struct id_index_event)) /
1962 		 sizeof(struct id_index_entry);
1963 	nr = ie->nr;
1964 	if (nr > max_nr)
1965 		return -EINVAL;
1966 
1967 	if (dump_trace)
1968 		fprintf(stdout, " nr: %zu\n", nr);
1969 
1970 	for (i = 0; i < nr; i++) {
1971 		struct id_index_entry *e = &ie->entries[i];
1972 		struct perf_sample_id *sid;
1973 
1974 		if (dump_trace) {
1975 			fprintf(stdout,	" ... id: %"PRIu64, e->id);
1976 			fprintf(stdout,	"  idx: %"PRIu64, e->idx);
1977 			fprintf(stdout,	"  cpu: %"PRId64, e->cpu);
1978 			fprintf(stdout,	"  tid: %"PRId64"\n", e->tid);
1979 		}
1980 
1981 		sid = perf_evlist__id2sid(evlist, e->id);
1982 		if (!sid)
1983 			return -ENOENT;
1984 		sid->idx = e->idx;
1985 		sid->cpu = e->cpu;
1986 		sid->tid = e->tid;
1987 	}
1988 	return 0;
1989 }
1990 
1991 int perf_event__synthesize_id_index(struct perf_tool *tool,
1992 				    perf_event__handler_t process,
1993 				    struct perf_evlist *evlist,
1994 				    struct machine *machine)
1995 {
1996 	union perf_event *ev;
1997 	struct perf_evsel *evsel;
1998 	size_t nr = 0, i = 0, sz, max_nr, n;
1999 	int err;
2000 
2001 	pr_debug2("Synthesizing id index\n");
2002 
2003 	max_nr = (UINT16_MAX - sizeof(struct id_index_event)) /
2004 		 sizeof(struct id_index_entry);
2005 
2006 	evlist__for_each(evlist, evsel)
2007 		nr += evsel->ids;
2008 
2009 	n = nr > max_nr ? max_nr : nr;
2010 	sz = sizeof(struct id_index_event) + n * sizeof(struct id_index_entry);
2011 	ev = zalloc(sz);
2012 	if (!ev)
2013 		return -ENOMEM;
2014 
2015 	ev->id_index.header.type = PERF_RECORD_ID_INDEX;
2016 	ev->id_index.header.size = sz;
2017 	ev->id_index.nr = n;
2018 
2019 	evlist__for_each(evlist, evsel) {
2020 		u32 j;
2021 
2022 		for (j = 0; j < evsel->ids; j++) {
2023 			struct id_index_entry *e;
2024 			struct perf_sample_id *sid;
2025 
2026 			if (i >= n) {
2027 				err = process(tool, ev, NULL, machine);
2028 				if (err)
2029 					goto out_err;
2030 				nr -= n;
2031 				i = 0;
2032 			}
2033 
2034 			e = &ev->id_index.entries[i++];
2035 
2036 			e->id = evsel->id[j];
2037 
2038 			sid = perf_evlist__id2sid(evlist, e->id);
2039 			if (!sid) {
2040 				free(ev);
2041 				return -ENOENT;
2042 			}
2043 
2044 			e->idx = sid->idx;
2045 			e->cpu = sid->cpu;
2046 			e->tid = sid->tid;
2047 		}
2048 	}
2049 
2050 	sz = sizeof(struct id_index_event) + nr * sizeof(struct id_index_entry);
2051 	ev->id_index.header.size = sz;
2052 	ev->id_index.nr = nr;
2053 
2054 	err = process(tool, ev, NULL, machine);
2055 out_err:
2056 	free(ev);
2057 
2058 	return err;
2059 }
2060