1 // SPDX-License-Identifier: GPL-2.0-only
2 
3 #include "util/cgroup.h"
4 #include "util/data.h"
5 #include "util/debug.h"
6 #include "util/dso.h"
7 #include "util/event.h"
8 #include "util/evlist.h"
9 #include "util/machine.h"
10 #include "util/map.h"
11 #include "util/map_symbol.h"
12 #include "util/branch.h"
13 #include "util/memswap.h"
14 #include "util/namespaces.h"
15 #include "util/session.h"
16 #include "util/stat.h"
17 #include "util/symbol.h"
18 #include "util/synthetic-events.h"
19 #include "util/target.h"
20 #include "util/time-utils.h"
21 #include <linux/bitops.h>
22 #include <linux/kernel.h>
23 #include <linux/string.h>
24 #include <linux/zalloc.h>
25 #include <linux/perf_event.h>
26 #include <asm/bug.h>
27 #include <perf/evsel.h>
28 #include <perf/cpumap.h>
29 #include <internal/lib.h> // page_size
30 #include <internal/threadmap.h>
31 #include <perf/threadmap.h>
32 #include <symbol/kallsyms.h>
33 #include <dirent.h>
34 #include <errno.h>
35 #include <inttypes.h>
36 #include <stdio.h>
37 #include <string.h>
38 #include <uapi/linux/mman.h> /* To get things like MAP_HUGETLB even on older libc headers */
39 #include <api/fs/fs.h>
40 #include <api/io.h>
41 #include <sys/types.h>
42 #include <sys/stat.h>
43 #include <fcntl.h>
44 #include <unistd.h>
45 
46 #define DEFAULT_PROC_MAP_PARSE_TIMEOUT 500
47 
48 unsigned int proc_map_timeout = DEFAULT_PROC_MAP_PARSE_TIMEOUT;
49 
50 int perf_tool__process_synth_event(struct perf_tool *tool,
51 				   union perf_event *event,
52 				   struct machine *machine,
53 				   perf_event__handler_t process)
54 {
55 	struct perf_sample synth_sample = {
56 		.pid	   = -1,
57 		.tid	   = -1,
58 		.time	   = -1,
59 		.stream_id = -1,
60 		.cpu	   = -1,
61 		.period	   = 1,
62 		.cpumode   = event->header.misc & PERF_RECORD_MISC_CPUMODE_MASK,
63 	};
64 
65 	return process(tool, event, &synth_sample, machine);
66 };
67 
68 /*
69  * Assumes that the first 4095 bytes of /proc/pid/stat contains
70  * the comm, tgid and ppid.
71  */
72 static int perf_event__get_comm_ids(pid_t pid, pid_t tid, char *comm, size_t len,
73 				    pid_t *tgid, pid_t *ppid, bool *kernel)
74 {
75 	char bf[4096];
76 	int fd;
77 	size_t size = 0;
78 	ssize_t n;
79 	char *name, *tgids, *ppids, *vmpeak, *threads;
80 
81 	*tgid = -1;
82 	*ppid = -1;
83 
84 	if (pid)
85 		snprintf(bf, sizeof(bf), "/proc/%d/task/%d/status", pid, tid);
86 	else
87 		snprintf(bf, sizeof(bf), "/proc/%d/status", tid);
88 
89 	fd = open(bf, O_RDONLY);
90 	if (fd < 0) {
91 		pr_debug("couldn't open %s\n", bf);
92 		return -1;
93 	}
94 
95 	n = read(fd, bf, sizeof(bf) - 1);
96 	close(fd);
97 	if (n <= 0) {
98 		pr_warning("Couldn't get COMM, tigd and ppid for pid %d\n",
99 			   tid);
100 		return -1;
101 	}
102 	bf[n] = '\0';
103 
104 	name = strstr(bf, "Name:");
105 	tgids = strstr(name ?: bf, "Tgid:");
106 	ppids = strstr(tgids ?: bf, "PPid:");
107 	vmpeak = strstr(ppids ?: bf, "VmPeak:");
108 
109 	if (vmpeak)
110 		threads = NULL;
111 	else
112 		threads = strstr(ppids ?: bf, "Threads:");
113 
114 	if (name) {
115 		char *nl;
116 
117 		name = skip_spaces(name + 5);  /* strlen("Name:") */
118 		nl = strchr(name, '\n');
119 		if (nl)
120 			*nl = '\0';
121 
122 		size = strlen(name);
123 		if (size >= len)
124 			size = len - 1;
125 		memcpy(comm, name, size);
126 		comm[size] = '\0';
127 	} else {
128 		pr_debug("Name: string not found for pid %d\n", tid);
129 	}
130 
131 	if (tgids) {
132 		tgids += 5;  /* strlen("Tgid:") */
133 		*tgid = atoi(tgids);
134 	} else {
135 		pr_debug("Tgid: string not found for pid %d\n", tid);
136 	}
137 
138 	if (ppids) {
139 		ppids += 5;  /* strlen("PPid:") */
140 		*ppid = atoi(ppids);
141 	} else {
142 		pr_debug("PPid: string not found for pid %d\n", tid);
143 	}
144 
145 	if (!vmpeak && threads)
146 		*kernel = true;
147 	else
148 		*kernel = false;
149 
150 	return 0;
151 }
152 
153 static int perf_event__prepare_comm(union perf_event *event, pid_t pid, pid_t tid,
154 				    struct machine *machine,
155 				    pid_t *tgid, pid_t *ppid, bool *kernel)
156 {
157 	size_t size;
158 
159 	*ppid = -1;
160 
161 	memset(&event->comm, 0, sizeof(event->comm));
162 
163 	if (machine__is_host(machine)) {
164 		if (perf_event__get_comm_ids(pid, tid, event->comm.comm,
165 					     sizeof(event->comm.comm),
166 					     tgid, ppid, kernel) != 0) {
167 			return -1;
168 		}
169 	} else {
170 		*tgid = machine->pid;
171 	}
172 
173 	if (*tgid < 0)
174 		return -1;
175 
176 	event->comm.pid = *tgid;
177 	event->comm.header.type = PERF_RECORD_COMM;
178 
179 	size = strlen(event->comm.comm) + 1;
180 	size = PERF_ALIGN(size, sizeof(u64));
181 	memset(event->comm.comm + size, 0, machine->id_hdr_size);
182 	event->comm.header.size = (sizeof(event->comm) -
183 				(sizeof(event->comm.comm) - size) +
184 				machine->id_hdr_size);
185 	event->comm.tid = tid;
186 
187 	return 0;
188 }
189 
190 pid_t perf_event__synthesize_comm(struct perf_tool *tool,
191 					 union perf_event *event, pid_t pid,
192 					 perf_event__handler_t process,
193 					 struct machine *machine)
194 {
195 	pid_t tgid, ppid;
196 	bool kernel_thread;
197 
198 	if (perf_event__prepare_comm(event, 0, pid, machine, &tgid, &ppid,
199 				     &kernel_thread) != 0)
200 		return -1;
201 
202 	if (perf_tool__process_synth_event(tool, event, machine, process) != 0)
203 		return -1;
204 
205 	return tgid;
206 }
207 
208 static void perf_event__get_ns_link_info(pid_t pid, const char *ns,
209 					 struct perf_ns_link_info *ns_link_info)
210 {
211 	struct stat64 st;
212 	char proc_ns[128];
213 
214 	sprintf(proc_ns, "/proc/%u/ns/%s", pid, ns);
215 	if (stat64(proc_ns, &st) == 0) {
216 		ns_link_info->dev = st.st_dev;
217 		ns_link_info->ino = st.st_ino;
218 	}
219 }
220 
221 int perf_event__synthesize_namespaces(struct perf_tool *tool,
222 				      union perf_event *event,
223 				      pid_t pid, pid_t tgid,
224 				      perf_event__handler_t process,
225 				      struct machine *machine)
226 {
227 	u32 idx;
228 	struct perf_ns_link_info *ns_link_info;
229 
230 	if (!tool || !tool->namespace_events)
231 		return 0;
232 
233 	memset(&event->namespaces, 0, (sizeof(event->namespaces) +
234 	       (NR_NAMESPACES * sizeof(struct perf_ns_link_info)) +
235 	       machine->id_hdr_size));
236 
237 	event->namespaces.pid = tgid;
238 	event->namespaces.tid = pid;
239 
240 	event->namespaces.nr_namespaces = NR_NAMESPACES;
241 
242 	ns_link_info = event->namespaces.link_info;
243 
244 	for (idx = 0; idx < event->namespaces.nr_namespaces; idx++)
245 		perf_event__get_ns_link_info(pid, perf_ns__name(idx),
246 					     &ns_link_info[idx]);
247 
248 	event->namespaces.header.type = PERF_RECORD_NAMESPACES;
249 
250 	event->namespaces.header.size = (sizeof(event->namespaces) +
251 			(NR_NAMESPACES * sizeof(struct perf_ns_link_info)) +
252 			machine->id_hdr_size);
253 
254 	if (perf_tool__process_synth_event(tool, event, machine, process) != 0)
255 		return -1;
256 
257 	return 0;
258 }
259 
260 static int perf_event__synthesize_fork(struct perf_tool *tool,
261 				       union perf_event *event,
262 				       pid_t pid, pid_t tgid, pid_t ppid,
263 				       perf_event__handler_t process,
264 				       struct machine *machine)
265 {
266 	memset(&event->fork, 0, sizeof(event->fork) + machine->id_hdr_size);
267 
268 	/*
269 	 * for main thread set parent to ppid from status file. For other
270 	 * threads set parent pid to main thread. ie., assume main thread
271 	 * spawns all threads in a process
272 	*/
273 	if (tgid == pid) {
274 		event->fork.ppid = ppid;
275 		event->fork.ptid = ppid;
276 	} else {
277 		event->fork.ppid = tgid;
278 		event->fork.ptid = tgid;
279 	}
280 	event->fork.pid  = tgid;
281 	event->fork.tid  = pid;
282 	event->fork.header.type = PERF_RECORD_FORK;
283 	event->fork.header.misc = PERF_RECORD_MISC_FORK_EXEC;
284 
285 	event->fork.header.size = (sizeof(event->fork) + machine->id_hdr_size);
286 
287 	if (perf_tool__process_synth_event(tool, event, machine, process) != 0)
288 		return -1;
289 
290 	return 0;
291 }
292 
293 static bool read_proc_maps_line(struct io *io, __u64 *start, __u64 *end,
294 				u32 *prot, u32 *flags, __u64 *offset,
295 				u32 *maj, u32 *min,
296 				__u64 *inode,
297 				ssize_t pathname_size, char *pathname)
298 {
299 	__u64 temp;
300 	int ch;
301 	char *start_pathname = pathname;
302 
303 	if (io__get_hex(io, start) != '-')
304 		return false;
305 	if (io__get_hex(io, end) != ' ')
306 		return false;
307 
308 	/* map protection and flags bits */
309 	*prot = 0;
310 	ch = io__get_char(io);
311 	if (ch == 'r')
312 		*prot |= PROT_READ;
313 	else if (ch != '-')
314 		return false;
315 	ch = io__get_char(io);
316 	if (ch == 'w')
317 		*prot |= PROT_WRITE;
318 	else if (ch != '-')
319 		return false;
320 	ch = io__get_char(io);
321 	if (ch == 'x')
322 		*prot |= PROT_EXEC;
323 	else if (ch != '-')
324 		return false;
325 	ch = io__get_char(io);
326 	if (ch == 's')
327 		*flags = MAP_SHARED;
328 	else if (ch == 'p')
329 		*flags = MAP_PRIVATE;
330 	else
331 		return false;
332 	if (io__get_char(io) != ' ')
333 		return false;
334 
335 	if (io__get_hex(io, offset) != ' ')
336 		return false;
337 
338 	if (io__get_hex(io, &temp) != ':')
339 		return false;
340 	*maj = temp;
341 	if (io__get_hex(io, &temp) != ' ')
342 		return false;
343 	*min = temp;
344 
345 	ch = io__get_dec(io, inode);
346 	if (ch != ' ') {
347 		*pathname = '\0';
348 		return ch == '\n';
349 	}
350 	do {
351 		ch = io__get_char(io);
352 	} while (ch == ' ');
353 	while (true) {
354 		if (ch < 0)
355 			return false;
356 		if (ch == '\0' || ch == '\n' ||
357 		    (pathname + 1 - start_pathname) >= pathname_size) {
358 			*pathname = '\0';
359 			return true;
360 		}
361 		*pathname++ = ch;
362 		ch = io__get_char(io);
363 	}
364 }
365 
366 static void perf_record_mmap2__read_build_id(struct perf_record_mmap2 *event,
367 					     bool is_kernel)
368 {
369 	struct build_id bid;
370 	int rc;
371 
372 	if (is_kernel)
373 		rc = sysfs__read_build_id("/sys/kernel/notes", &bid);
374 	else
375 		rc = filename__read_build_id(event->filename, &bid) > 0 ? 0 : -1;
376 
377 	if (rc == 0) {
378 		memcpy(event->build_id, bid.data, sizeof(bid.data));
379 		event->build_id_size = (u8) bid.size;
380 		event->header.misc |= PERF_RECORD_MISC_MMAP_BUILD_ID;
381 		event->__reserved_1 = 0;
382 		event->__reserved_2 = 0;
383 	} else {
384 		if (event->filename[0] == '/') {
385 			pr_debug2("Failed to read build ID for %s\n",
386 				  event->filename);
387 		}
388 	}
389 }
390 
391 int perf_event__synthesize_mmap_events(struct perf_tool *tool,
392 				       union perf_event *event,
393 				       pid_t pid, pid_t tgid,
394 				       perf_event__handler_t process,
395 				       struct machine *machine,
396 				       bool mmap_data)
397 {
398 	unsigned long long t;
399 	char bf[BUFSIZ];
400 	struct io io;
401 	bool truncation = false;
402 	unsigned long long timeout = proc_map_timeout * 1000000ULL;
403 	int rc = 0;
404 	const char *hugetlbfs_mnt = hugetlbfs__mountpoint();
405 	int hugetlbfs_mnt_len = hugetlbfs_mnt ? strlen(hugetlbfs_mnt) : 0;
406 
407 	if (machine__is_default_guest(machine))
408 		return 0;
409 
410 	snprintf(bf, sizeof(bf), "%s/proc/%d/task/%d/maps",
411 		machine->root_dir, pid, pid);
412 
413 	io.fd = open(bf, O_RDONLY, 0);
414 	if (io.fd < 0) {
415 		/*
416 		 * We raced with a task exiting - just return:
417 		 */
418 		pr_debug("couldn't open %s\n", bf);
419 		return -1;
420 	}
421 	io__init(&io, io.fd, bf, sizeof(bf));
422 
423 	event->header.type = PERF_RECORD_MMAP2;
424 	t = rdclock();
425 
426 	while (!io.eof) {
427 		static const char anonstr[] = "//anon";
428 		size_t size, aligned_size;
429 
430 		/* ensure null termination since stack will be reused. */
431 		event->mmap2.filename[0] = '\0';
432 
433 		/* 00400000-0040c000 r-xp 00000000 fd:01 41038  /bin/cat */
434 		if (!read_proc_maps_line(&io,
435 					&event->mmap2.start,
436 					&event->mmap2.len,
437 					&event->mmap2.prot,
438 					&event->mmap2.flags,
439 					&event->mmap2.pgoff,
440 					&event->mmap2.maj,
441 					&event->mmap2.min,
442 					&event->mmap2.ino,
443 					sizeof(event->mmap2.filename),
444 					event->mmap2.filename))
445 			continue;
446 
447 		if ((rdclock() - t) > timeout) {
448 			pr_warning("Reading %s/proc/%d/task/%d/maps time out. "
449 				   "You may want to increase "
450 				   "the time limit by --proc-map-timeout\n",
451 				   machine->root_dir, pid, pid);
452 			truncation = true;
453 			goto out;
454 		}
455 
456 		event->mmap2.ino_generation = 0;
457 
458 		/*
459 		 * Just like the kernel, see __perf_event_mmap in kernel/perf_event.c
460 		 */
461 		if (machine__is_host(machine))
462 			event->header.misc = PERF_RECORD_MISC_USER;
463 		else
464 			event->header.misc = PERF_RECORD_MISC_GUEST_USER;
465 
466 		if ((event->mmap2.prot & PROT_EXEC) == 0) {
467 			if (!mmap_data || (event->mmap2.prot & PROT_READ) == 0)
468 				continue;
469 
470 			event->header.misc |= PERF_RECORD_MISC_MMAP_DATA;
471 		}
472 
473 out:
474 		if (truncation)
475 			event->header.misc |= PERF_RECORD_MISC_PROC_MAP_PARSE_TIMEOUT;
476 
477 		if (!strcmp(event->mmap2.filename, ""))
478 			strcpy(event->mmap2.filename, anonstr);
479 
480 		if (hugetlbfs_mnt_len &&
481 		    !strncmp(event->mmap2.filename, hugetlbfs_mnt,
482 			     hugetlbfs_mnt_len)) {
483 			strcpy(event->mmap2.filename, anonstr);
484 			event->mmap2.flags |= MAP_HUGETLB;
485 		}
486 
487 		size = strlen(event->mmap2.filename) + 1;
488 		aligned_size = PERF_ALIGN(size, sizeof(u64));
489 		event->mmap2.len -= event->mmap.start;
490 		event->mmap2.header.size = (sizeof(event->mmap2) -
491 					(sizeof(event->mmap2.filename) - aligned_size));
492 		memset(event->mmap2.filename + size, 0, machine->id_hdr_size +
493 			(aligned_size - size));
494 		event->mmap2.header.size += machine->id_hdr_size;
495 		event->mmap2.pid = tgid;
496 		event->mmap2.tid = pid;
497 
498 		if (symbol_conf.buildid_mmap2)
499 			perf_record_mmap2__read_build_id(&event->mmap2, false);
500 
501 		if (perf_tool__process_synth_event(tool, event, machine, process) != 0) {
502 			rc = -1;
503 			break;
504 		}
505 
506 		if (truncation)
507 			break;
508 	}
509 
510 	close(io.fd);
511 	return rc;
512 }
513 
514 #ifdef HAVE_FILE_HANDLE
515 static int perf_event__synthesize_cgroup(struct perf_tool *tool,
516 					 union perf_event *event,
517 					 char *path, size_t mount_len,
518 					 perf_event__handler_t process,
519 					 struct machine *machine)
520 {
521 	size_t event_size = sizeof(event->cgroup) - sizeof(event->cgroup.path);
522 	size_t path_len = strlen(path) - mount_len + 1;
523 	struct {
524 		struct file_handle fh;
525 		uint64_t cgroup_id;
526 	} handle;
527 	int mount_id;
528 
529 	while (path_len % sizeof(u64))
530 		path[mount_len + path_len++] = '\0';
531 
532 	memset(&event->cgroup, 0, event_size);
533 
534 	event->cgroup.header.type = PERF_RECORD_CGROUP;
535 	event->cgroup.header.size = event_size + path_len + machine->id_hdr_size;
536 
537 	handle.fh.handle_bytes = sizeof(handle.cgroup_id);
538 	if (name_to_handle_at(AT_FDCWD, path, &handle.fh, &mount_id, 0) < 0) {
539 		pr_debug("stat failed: %s\n", path);
540 		return -1;
541 	}
542 
543 	event->cgroup.id = handle.cgroup_id;
544 	strncpy(event->cgroup.path, path + mount_len, path_len);
545 	memset(event->cgroup.path + path_len, 0, machine->id_hdr_size);
546 
547 	if (perf_tool__process_synth_event(tool, event, machine, process) < 0) {
548 		pr_debug("process synth event failed\n");
549 		return -1;
550 	}
551 
552 	return 0;
553 }
554 
555 static int perf_event__walk_cgroup_tree(struct perf_tool *tool,
556 					union perf_event *event,
557 					char *path, size_t mount_len,
558 					perf_event__handler_t process,
559 					struct machine *machine)
560 {
561 	size_t pos = strlen(path);
562 	DIR *d;
563 	struct dirent *dent;
564 	int ret = 0;
565 
566 	if (perf_event__synthesize_cgroup(tool, event, path, mount_len,
567 					  process, machine) < 0)
568 		return -1;
569 
570 	d = opendir(path);
571 	if (d == NULL) {
572 		pr_debug("failed to open directory: %s\n", path);
573 		return -1;
574 	}
575 
576 	while ((dent = readdir(d)) != NULL) {
577 		if (dent->d_type != DT_DIR)
578 			continue;
579 		if (!strcmp(dent->d_name, ".") ||
580 		    !strcmp(dent->d_name, ".."))
581 			continue;
582 
583 		/* any sane path should be less than PATH_MAX */
584 		if (strlen(path) + strlen(dent->d_name) + 1 >= PATH_MAX)
585 			continue;
586 
587 		if (path[pos - 1] != '/')
588 			strcat(path, "/");
589 		strcat(path, dent->d_name);
590 
591 		ret = perf_event__walk_cgroup_tree(tool, event, path,
592 						   mount_len, process, machine);
593 		if (ret < 0)
594 			break;
595 
596 		path[pos] = '\0';
597 	}
598 
599 	closedir(d);
600 	return ret;
601 }
602 
603 int perf_event__synthesize_cgroups(struct perf_tool *tool,
604 				   perf_event__handler_t process,
605 				   struct machine *machine)
606 {
607 	union perf_event event;
608 	char cgrp_root[PATH_MAX];
609 	size_t mount_len;  /* length of mount point in the path */
610 
611 	if (!tool || !tool->cgroup_events)
612 		return 0;
613 
614 	if (cgroupfs_find_mountpoint(cgrp_root, PATH_MAX, "perf_event") < 0) {
615 		pr_debug("cannot find cgroup mount point\n");
616 		return -1;
617 	}
618 
619 	mount_len = strlen(cgrp_root);
620 	/* make sure the path starts with a slash (after mount point) */
621 	strcat(cgrp_root, "/");
622 
623 	if (perf_event__walk_cgroup_tree(tool, &event, cgrp_root, mount_len,
624 					 process, machine) < 0)
625 		return -1;
626 
627 	return 0;
628 }
629 #else
630 int perf_event__synthesize_cgroups(struct perf_tool *tool __maybe_unused,
631 				   perf_event__handler_t process __maybe_unused,
632 				   struct machine *machine __maybe_unused)
633 {
634 	return -1;
635 }
636 #endif
637 
638 int perf_event__synthesize_modules(struct perf_tool *tool, perf_event__handler_t process,
639 				   struct machine *machine)
640 {
641 	int rc = 0;
642 	struct map *pos;
643 	struct maps *maps = machine__kernel_maps(machine);
644 	union perf_event *event;
645 	size_t size = symbol_conf.buildid_mmap2 ?
646 			sizeof(event->mmap2) : sizeof(event->mmap);
647 
648 	event = zalloc(size + machine->id_hdr_size);
649 	if (event == NULL) {
650 		pr_debug("Not enough memory synthesizing mmap event "
651 			 "for kernel modules\n");
652 		return -1;
653 	}
654 
655 	/*
656 	 * kernel uses 0 for user space maps, see kernel/perf_event.c
657 	 * __perf_event_mmap
658 	 */
659 	if (machine__is_host(machine))
660 		event->header.misc = PERF_RECORD_MISC_KERNEL;
661 	else
662 		event->header.misc = PERF_RECORD_MISC_GUEST_KERNEL;
663 
664 	maps__for_each_entry(maps, pos) {
665 		if (!__map__is_kmodule(pos))
666 			continue;
667 
668 		if (symbol_conf.buildid_mmap2) {
669 			size = PERF_ALIGN(pos->dso->long_name_len + 1, sizeof(u64));
670 			event->mmap2.header.type = PERF_RECORD_MMAP2;
671 			event->mmap2.header.size = (sizeof(event->mmap2) -
672 						(sizeof(event->mmap2.filename) - size));
673 			memset(event->mmap2.filename + size, 0, machine->id_hdr_size);
674 			event->mmap2.header.size += machine->id_hdr_size;
675 			event->mmap2.start = pos->start;
676 			event->mmap2.len   = pos->end - pos->start;
677 			event->mmap2.pid   = machine->pid;
678 
679 			memcpy(event->mmap2.filename, pos->dso->long_name,
680 			       pos->dso->long_name_len + 1);
681 
682 			perf_record_mmap2__read_build_id(&event->mmap2, false);
683 		} else {
684 			size = PERF_ALIGN(pos->dso->long_name_len + 1, sizeof(u64));
685 			event->mmap.header.type = PERF_RECORD_MMAP;
686 			event->mmap.header.size = (sizeof(event->mmap) -
687 						(sizeof(event->mmap.filename) - size));
688 			memset(event->mmap.filename + size, 0, machine->id_hdr_size);
689 			event->mmap.header.size += machine->id_hdr_size;
690 			event->mmap.start = pos->start;
691 			event->mmap.len   = pos->end - pos->start;
692 			event->mmap.pid   = machine->pid;
693 
694 			memcpy(event->mmap.filename, pos->dso->long_name,
695 			       pos->dso->long_name_len + 1);
696 		}
697 
698 		if (perf_tool__process_synth_event(tool, event, machine, process) != 0) {
699 			rc = -1;
700 			break;
701 		}
702 	}
703 
704 	free(event);
705 	return rc;
706 }
707 
708 static int filter_task(const struct dirent *dirent)
709 {
710 	return isdigit(dirent->d_name[0]);
711 }
712 
713 static int __event__synthesize_thread(union perf_event *comm_event,
714 				      union perf_event *mmap_event,
715 				      union perf_event *fork_event,
716 				      union perf_event *namespaces_event,
717 				      pid_t pid, int full, perf_event__handler_t process,
718 				      struct perf_tool *tool, struct machine *machine, bool mmap_data)
719 {
720 	char filename[PATH_MAX];
721 	struct dirent **dirent;
722 	pid_t tgid, ppid;
723 	int rc = 0;
724 	int i, n;
725 
726 	/* special case: only send one comm event using passed in pid */
727 	if (!full) {
728 		tgid = perf_event__synthesize_comm(tool, comm_event, pid,
729 						   process, machine);
730 
731 		if (tgid == -1)
732 			return -1;
733 
734 		if (perf_event__synthesize_namespaces(tool, namespaces_event, pid,
735 						      tgid, process, machine) < 0)
736 			return -1;
737 
738 		/*
739 		 * send mmap only for thread group leader
740 		 * see thread__init_maps()
741 		 */
742 		if (pid == tgid &&
743 		    perf_event__synthesize_mmap_events(tool, mmap_event, pid, tgid,
744 						       process, machine, mmap_data))
745 			return -1;
746 
747 		return 0;
748 	}
749 
750 	if (machine__is_default_guest(machine))
751 		return 0;
752 
753 	snprintf(filename, sizeof(filename), "%s/proc/%d/task",
754 		 machine->root_dir, pid);
755 
756 	n = scandir(filename, &dirent, filter_task, alphasort);
757 	if (n < 0)
758 		return n;
759 
760 	for (i = 0; i < n; i++) {
761 		char *end;
762 		pid_t _pid;
763 		bool kernel_thread = false;
764 
765 		_pid = strtol(dirent[i]->d_name, &end, 10);
766 		if (*end)
767 			continue;
768 
769 		rc = -1;
770 		if (perf_event__prepare_comm(comm_event, pid, _pid, machine,
771 					     &tgid, &ppid, &kernel_thread) != 0)
772 			break;
773 
774 		if (perf_event__synthesize_fork(tool, fork_event, _pid, tgid,
775 						ppid, process, machine) < 0)
776 			break;
777 
778 		if (perf_event__synthesize_namespaces(tool, namespaces_event, _pid,
779 						      tgid, process, machine) < 0)
780 			break;
781 
782 		/*
783 		 * Send the prepared comm event
784 		 */
785 		if (perf_tool__process_synth_event(tool, comm_event, machine, process) != 0)
786 			break;
787 
788 		rc = 0;
789 		if (_pid == pid && !kernel_thread) {
790 			/* process the parent's maps too */
791 			rc = perf_event__synthesize_mmap_events(tool, mmap_event, pid, tgid,
792 						process, machine, mmap_data);
793 			if (rc)
794 				break;
795 		}
796 	}
797 
798 	for (i = 0; i < n; i++)
799 		zfree(&dirent[i]);
800 	free(dirent);
801 
802 	return rc;
803 }
804 
805 int perf_event__synthesize_thread_map(struct perf_tool *tool,
806 				      struct perf_thread_map *threads,
807 				      perf_event__handler_t process,
808 				      struct machine *machine,
809 				      bool mmap_data)
810 {
811 	union perf_event *comm_event, *mmap_event, *fork_event;
812 	union perf_event *namespaces_event;
813 	int err = -1, thread, j;
814 
815 	comm_event = malloc(sizeof(comm_event->comm) + machine->id_hdr_size);
816 	if (comm_event == NULL)
817 		goto out;
818 
819 	mmap_event = malloc(sizeof(mmap_event->mmap2) + machine->id_hdr_size);
820 	if (mmap_event == NULL)
821 		goto out_free_comm;
822 
823 	fork_event = malloc(sizeof(fork_event->fork) + machine->id_hdr_size);
824 	if (fork_event == NULL)
825 		goto out_free_mmap;
826 
827 	namespaces_event = malloc(sizeof(namespaces_event->namespaces) +
828 				  (NR_NAMESPACES * sizeof(struct perf_ns_link_info)) +
829 				  machine->id_hdr_size);
830 	if (namespaces_event == NULL)
831 		goto out_free_fork;
832 
833 	err = 0;
834 	for (thread = 0; thread < threads->nr; ++thread) {
835 		if (__event__synthesize_thread(comm_event, mmap_event,
836 					       fork_event, namespaces_event,
837 					       perf_thread_map__pid(threads, thread), 0,
838 					       process, tool, machine,
839 					       mmap_data)) {
840 			err = -1;
841 			break;
842 		}
843 
844 		/*
845 		 * comm.pid is set to thread group id by
846 		 * perf_event__synthesize_comm
847 		 */
848 		if ((int) comm_event->comm.pid != perf_thread_map__pid(threads, thread)) {
849 			bool need_leader = true;
850 
851 			/* is thread group leader in thread_map? */
852 			for (j = 0; j < threads->nr; ++j) {
853 				if ((int) comm_event->comm.pid == perf_thread_map__pid(threads, j)) {
854 					need_leader = false;
855 					break;
856 				}
857 			}
858 
859 			/* if not, generate events for it */
860 			if (need_leader &&
861 			    __event__synthesize_thread(comm_event, mmap_event,
862 						       fork_event, namespaces_event,
863 						       comm_event->comm.pid, 0,
864 						       process, tool, machine,
865 						       mmap_data)) {
866 				err = -1;
867 				break;
868 			}
869 		}
870 	}
871 	free(namespaces_event);
872 out_free_fork:
873 	free(fork_event);
874 out_free_mmap:
875 	free(mmap_event);
876 out_free_comm:
877 	free(comm_event);
878 out:
879 	return err;
880 }
881 
882 static int __perf_event__synthesize_threads(struct perf_tool *tool,
883 					    perf_event__handler_t process,
884 					    struct machine *machine,
885 					    bool mmap_data,
886 					    struct dirent **dirent,
887 					    int start,
888 					    int num)
889 {
890 	union perf_event *comm_event, *mmap_event, *fork_event;
891 	union perf_event *namespaces_event;
892 	int err = -1;
893 	char *end;
894 	pid_t pid;
895 	int i;
896 
897 	comm_event = malloc(sizeof(comm_event->comm) + machine->id_hdr_size);
898 	if (comm_event == NULL)
899 		goto out;
900 
901 	mmap_event = malloc(sizeof(mmap_event->mmap2) + machine->id_hdr_size);
902 	if (mmap_event == NULL)
903 		goto out_free_comm;
904 
905 	fork_event = malloc(sizeof(fork_event->fork) + machine->id_hdr_size);
906 	if (fork_event == NULL)
907 		goto out_free_mmap;
908 
909 	namespaces_event = malloc(sizeof(namespaces_event->namespaces) +
910 				  (NR_NAMESPACES * sizeof(struct perf_ns_link_info)) +
911 				  machine->id_hdr_size);
912 	if (namespaces_event == NULL)
913 		goto out_free_fork;
914 
915 	for (i = start; i < start + num; i++) {
916 		if (!isdigit(dirent[i]->d_name[0]))
917 			continue;
918 
919 		pid = (pid_t)strtol(dirent[i]->d_name, &end, 10);
920 		/* only interested in proper numerical dirents */
921 		if (*end)
922 			continue;
923 		/*
924 		 * We may race with exiting thread, so don't stop just because
925 		 * one thread couldn't be synthesized.
926 		 */
927 		__event__synthesize_thread(comm_event, mmap_event, fork_event,
928 					   namespaces_event, pid, 1, process,
929 					   tool, machine, mmap_data);
930 	}
931 	err = 0;
932 
933 	free(namespaces_event);
934 out_free_fork:
935 	free(fork_event);
936 out_free_mmap:
937 	free(mmap_event);
938 out_free_comm:
939 	free(comm_event);
940 out:
941 	return err;
942 }
943 
944 struct synthesize_threads_arg {
945 	struct perf_tool *tool;
946 	perf_event__handler_t process;
947 	struct machine *machine;
948 	bool mmap_data;
949 	struct dirent **dirent;
950 	int num;
951 	int start;
952 };
953 
954 static void *synthesize_threads_worker(void *arg)
955 {
956 	struct synthesize_threads_arg *args = arg;
957 
958 	__perf_event__synthesize_threads(args->tool, args->process,
959 					 args->machine, args->mmap_data,
960 					 args->dirent,
961 					 args->start, args->num);
962 	return NULL;
963 }
964 
965 int perf_event__synthesize_threads(struct perf_tool *tool,
966 				   perf_event__handler_t process,
967 				   struct machine *machine,
968 				   bool mmap_data,
969 				   unsigned int nr_threads_synthesize)
970 {
971 	struct synthesize_threads_arg *args = NULL;
972 	pthread_t *synthesize_threads = NULL;
973 	char proc_path[PATH_MAX];
974 	struct dirent **dirent;
975 	int num_per_thread;
976 	int m, n, i, j;
977 	int thread_nr;
978 	int base = 0;
979 	int err = -1;
980 
981 
982 	if (machine__is_default_guest(machine))
983 		return 0;
984 
985 	snprintf(proc_path, sizeof(proc_path), "%s/proc", machine->root_dir);
986 	n = scandir(proc_path, &dirent, filter_task, alphasort);
987 	if (n < 0)
988 		return err;
989 
990 	if (nr_threads_synthesize == UINT_MAX)
991 		thread_nr = sysconf(_SC_NPROCESSORS_ONLN);
992 	else
993 		thread_nr = nr_threads_synthesize;
994 
995 	if (thread_nr <= 1) {
996 		err = __perf_event__synthesize_threads(tool, process,
997 						       machine, mmap_data,
998 						       dirent, base, n);
999 		goto free_dirent;
1000 	}
1001 	if (thread_nr > n)
1002 		thread_nr = n;
1003 
1004 	synthesize_threads = calloc(sizeof(pthread_t), thread_nr);
1005 	if (synthesize_threads == NULL)
1006 		goto free_dirent;
1007 
1008 	args = calloc(sizeof(*args), thread_nr);
1009 	if (args == NULL)
1010 		goto free_threads;
1011 
1012 	num_per_thread = n / thread_nr;
1013 	m = n % thread_nr;
1014 	for (i = 0; i < thread_nr; i++) {
1015 		args[i].tool = tool;
1016 		args[i].process = process;
1017 		args[i].machine = machine;
1018 		args[i].mmap_data = mmap_data;
1019 		args[i].dirent = dirent;
1020 	}
1021 	for (i = 0; i < m; i++) {
1022 		args[i].num = num_per_thread + 1;
1023 		args[i].start = i * args[i].num;
1024 	}
1025 	if (i != 0)
1026 		base = args[i-1].start + args[i-1].num;
1027 	for (j = i; j < thread_nr; j++) {
1028 		args[j].num = num_per_thread;
1029 		args[j].start = base + (j - i) * args[i].num;
1030 	}
1031 
1032 	for (i = 0; i < thread_nr; i++) {
1033 		if (pthread_create(&synthesize_threads[i], NULL,
1034 				   synthesize_threads_worker, &args[i]))
1035 			goto out_join;
1036 	}
1037 	err = 0;
1038 out_join:
1039 	for (i = 0; i < thread_nr; i++)
1040 		pthread_join(synthesize_threads[i], NULL);
1041 	free(args);
1042 free_threads:
1043 	free(synthesize_threads);
1044 free_dirent:
1045 	for (i = 0; i < n; i++)
1046 		zfree(&dirent[i]);
1047 	free(dirent);
1048 
1049 	return err;
1050 }
1051 
1052 int __weak perf_event__synthesize_extra_kmaps(struct perf_tool *tool __maybe_unused,
1053 					      perf_event__handler_t process __maybe_unused,
1054 					      struct machine *machine __maybe_unused)
1055 {
1056 	return 0;
1057 }
1058 
1059 static int __perf_event__synthesize_kernel_mmap(struct perf_tool *tool,
1060 						perf_event__handler_t process,
1061 						struct machine *machine)
1062 {
1063 	union perf_event *event;
1064 	size_t size = symbol_conf.buildid_mmap2 ?
1065 			sizeof(event->mmap2) : sizeof(event->mmap);
1066 	struct map *map = machine__kernel_map(machine);
1067 	struct kmap *kmap;
1068 	int err;
1069 
1070 	if (map == NULL)
1071 		return -1;
1072 
1073 	kmap = map__kmap(map);
1074 	if (!kmap->ref_reloc_sym)
1075 		return -1;
1076 
1077 	/*
1078 	 * We should get this from /sys/kernel/sections/.text, but till that is
1079 	 * available use this, and after it is use this as a fallback for older
1080 	 * kernels.
1081 	 */
1082 	event = zalloc(size + machine->id_hdr_size);
1083 	if (event == NULL) {
1084 		pr_debug("Not enough memory synthesizing mmap event "
1085 			 "for kernel modules\n");
1086 		return -1;
1087 	}
1088 
1089 	if (machine__is_host(machine)) {
1090 		/*
1091 		 * kernel uses PERF_RECORD_MISC_USER for user space maps,
1092 		 * see kernel/perf_event.c __perf_event_mmap
1093 		 */
1094 		event->header.misc = PERF_RECORD_MISC_KERNEL;
1095 	} else {
1096 		event->header.misc = PERF_RECORD_MISC_GUEST_KERNEL;
1097 	}
1098 
1099 	if (symbol_conf.buildid_mmap2) {
1100 		size = snprintf(event->mmap2.filename, sizeof(event->mmap2.filename),
1101 				"%s%s", machine->mmap_name, kmap->ref_reloc_sym->name) + 1;
1102 		size = PERF_ALIGN(size, sizeof(u64));
1103 		event->mmap2.header.type = PERF_RECORD_MMAP2;
1104 		event->mmap2.header.size = (sizeof(event->mmap2) -
1105 				(sizeof(event->mmap2.filename) - size) + machine->id_hdr_size);
1106 		event->mmap2.pgoff = kmap->ref_reloc_sym->addr;
1107 		event->mmap2.start = map->start;
1108 		event->mmap2.len   = map->end - event->mmap.start;
1109 		event->mmap2.pid   = machine->pid;
1110 
1111 		perf_record_mmap2__read_build_id(&event->mmap2, true);
1112 	} else {
1113 		size = snprintf(event->mmap.filename, sizeof(event->mmap.filename),
1114 				"%s%s", machine->mmap_name, kmap->ref_reloc_sym->name) + 1;
1115 		size = PERF_ALIGN(size, sizeof(u64));
1116 		event->mmap.header.type = PERF_RECORD_MMAP;
1117 		event->mmap.header.size = (sizeof(event->mmap) -
1118 				(sizeof(event->mmap.filename) - size) + machine->id_hdr_size);
1119 		event->mmap.pgoff = kmap->ref_reloc_sym->addr;
1120 		event->mmap.start = map->start;
1121 		event->mmap.len   = map->end - event->mmap.start;
1122 		event->mmap.pid   = machine->pid;
1123 	}
1124 
1125 	err = perf_tool__process_synth_event(tool, event, machine, process);
1126 	free(event);
1127 
1128 	return err;
1129 }
1130 
1131 int perf_event__synthesize_kernel_mmap(struct perf_tool *tool,
1132 				       perf_event__handler_t process,
1133 				       struct machine *machine)
1134 {
1135 	int err;
1136 
1137 	err = __perf_event__synthesize_kernel_mmap(tool, process, machine);
1138 	if (err < 0)
1139 		return err;
1140 
1141 	return perf_event__synthesize_extra_kmaps(tool, process, machine);
1142 }
1143 
1144 int perf_event__synthesize_thread_map2(struct perf_tool *tool,
1145 				      struct perf_thread_map *threads,
1146 				      perf_event__handler_t process,
1147 				      struct machine *machine)
1148 {
1149 	union perf_event *event;
1150 	int i, err, size;
1151 
1152 	size  = sizeof(event->thread_map);
1153 	size +=	threads->nr * sizeof(event->thread_map.entries[0]);
1154 
1155 	event = zalloc(size);
1156 	if (!event)
1157 		return -ENOMEM;
1158 
1159 	event->header.type = PERF_RECORD_THREAD_MAP;
1160 	event->header.size = size;
1161 	event->thread_map.nr = threads->nr;
1162 
1163 	for (i = 0; i < threads->nr; i++) {
1164 		struct perf_record_thread_map_entry *entry = &event->thread_map.entries[i];
1165 		char *comm = perf_thread_map__comm(threads, i);
1166 
1167 		if (!comm)
1168 			comm = (char *) "";
1169 
1170 		entry->pid = perf_thread_map__pid(threads, i);
1171 		strncpy((char *) &entry->comm, comm, sizeof(entry->comm));
1172 	}
1173 
1174 	err = process(tool, event, NULL, machine);
1175 
1176 	free(event);
1177 	return err;
1178 }
1179 
1180 static void synthesize_cpus(struct cpu_map_entries *cpus,
1181 			    struct perf_cpu_map *map)
1182 {
1183 	int i;
1184 
1185 	cpus->nr = map->nr;
1186 
1187 	for (i = 0; i < map->nr; i++)
1188 		cpus->cpu[i] = map->map[i];
1189 }
1190 
1191 static void synthesize_mask(struct perf_record_record_cpu_map *mask,
1192 			    struct perf_cpu_map *map, int max)
1193 {
1194 	int i;
1195 
1196 	mask->nr = BITS_TO_LONGS(max);
1197 	mask->long_size = sizeof(long);
1198 
1199 	for (i = 0; i < map->nr; i++)
1200 		set_bit(map->map[i], mask->mask);
1201 }
1202 
1203 static size_t cpus_size(struct perf_cpu_map *map)
1204 {
1205 	return sizeof(struct cpu_map_entries) + map->nr * sizeof(u16);
1206 }
1207 
1208 static size_t mask_size(struct perf_cpu_map *map, int *max)
1209 {
1210 	int i;
1211 
1212 	*max = 0;
1213 
1214 	for (i = 0; i < map->nr; i++) {
1215 		/* bit position of the cpu is + 1 */
1216 		int bit = map->map[i] + 1;
1217 
1218 		if (bit > *max)
1219 			*max = bit;
1220 	}
1221 
1222 	return sizeof(struct perf_record_record_cpu_map) + BITS_TO_LONGS(*max) * sizeof(long);
1223 }
1224 
1225 void *cpu_map_data__alloc(struct perf_cpu_map *map, size_t *size, u16 *type, int *max)
1226 {
1227 	size_t size_cpus, size_mask;
1228 	bool is_dummy = perf_cpu_map__empty(map);
1229 
1230 	/*
1231 	 * Both array and mask data have variable size based
1232 	 * on the number of cpus and their actual values.
1233 	 * The size of the 'struct perf_record_cpu_map_data' is:
1234 	 *
1235 	 *   array = size of 'struct cpu_map_entries' +
1236 	 *           number of cpus * sizeof(u64)
1237 	 *
1238 	 *   mask  = size of 'struct perf_record_record_cpu_map' +
1239 	 *           maximum cpu bit converted to size of longs
1240 	 *
1241 	 * and finally + the size of 'struct perf_record_cpu_map_data'.
1242 	 */
1243 	size_cpus = cpus_size(map);
1244 	size_mask = mask_size(map, max);
1245 
1246 	if (is_dummy || (size_cpus < size_mask)) {
1247 		*size += size_cpus;
1248 		*type  = PERF_CPU_MAP__CPUS;
1249 	} else {
1250 		*size += size_mask;
1251 		*type  = PERF_CPU_MAP__MASK;
1252 	}
1253 
1254 	*size += sizeof(struct perf_record_cpu_map_data);
1255 	*size = PERF_ALIGN(*size, sizeof(u64));
1256 	return zalloc(*size);
1257 }
1258 
1259 void cpu_map_data__synthesize(struct perf_record_cpu_map_data *data, struct perf_cpu_map *map,
1260 			      u16 type, int max)
1261 {
1262 	data->type = type;
1263 
1264 	switch (type) {
1265 	case PERF_CPU_MAP__CPUS:
1266 		synthesize_cpus((struct cpu_map_entries *) data->data, map);
1267 		break;
1268 	case PERF_CPU_MAP__MASK:
1269 		synthesize_mask((struct perf_record_record_cpu_map *)data->data, map, max);
1270 	default:
1271 		break;
1272 	}
1273 }
1274 
1275 static struct perf_record_cpu_map *cpu_map_event__new(struct perf_cpu_map *map)
1276 {
1277 	size_t size = sizeof(struct perf_record_cpu_map);
1278 	struct perf_record_cpu_map *event;
1279 	int max;
1280 	u16 type;
1281 
1282 	event = cpu_map_data__alloc(map, &size, &type, &max);
1283 	if (!event)
1284 		return NULL;
1285 
1286 	event->header.type = PERF_RECORD_CPU_MAP;
1287 	event->header.size = size;
1288 	event->data.type   = type;
1289 
1290 	cpu_map_data__synthesize(&event->data, map, type, max);
1291 	return event;
1292 }
1293 
1294 int perf_event__synthesize_cpu_map(struct perf_tool *tool,
1295 				   struct perf_cpu_map *map,
1296 				   perf_event__handler_t process,
1297 				   struct machine *machine)
1298 {
1299 	struct perf_record_cpu_map *event;
1300 	int err;
1301 
1302 	event = cpu_map_event__new(map);
1303 	if (!event)
1304 		return -ENOMEM;
1305 
1306 	err = process(tool, (union perf_event *) event, NULL, machine);
1307 
1308 	free(event);
1309 	return err;
1310 }
1311 
1312 int perf_event__synthesize_stat_config(struct perf_tool *tool,
1313 				       struct perf_stat_config *config,
1314 				       perf_event__handler_t process,
1315 				       struct machine *machine)
1316 {
1317 	struct perf_record_stat_config *event;
1318 	int size, i = 0, err;
1319 
1320 	size  = sizeof(*event);
1321 	size += (PERF_STAT_CONFIG_TERM__MAX * sizeof(event->data[0]));
1322 
1323 	event = zalloc(size);
1324 	if (!event)
1325 		return -ENOMEM;
1326 
1327 	event->header.type = PERF_RECORD_STAT_CONFIG;
1328 	event->header.size = size;
1329 	event->nr          = PERF_STAT_CONFIG_TERM__MAX;
1330 
1331 #define ADD(__term, __val)					\
1332 	event->data[i].tag = PERF_STAT_CONFIG_TERM__##__term;	\
1333 	event->data[i].val = __val;				\
1334 	i++;
1335 
1336 	ADD(AGGR_MODE,	config->aggr_mode)
1337 	ADD(INTERVAL,	config->interval)
1338 	ADD(SCALE,	config->scale)
1339 
1340 	WARN_ONCE(i != PERF_STAT_CONFIG_TERM__MAX,
1341 		  "stat config terms unbalanced\n");
1342 #undef ADD
1343 
1344 	err = process(tool, (union perf_event *) event, NULL, machine);
1345 
1346 	free(event);
1347 	return err;
1348 }
1349 
1350 int perf_event__synthesize_stat(struct perf_tool *tool,
1351 				u32 cpu, u32 thread, u64 id,
1352 				struct perf_counts_values *count,
1353 				perf_event__handler_t process,
1354 				struct machine *machine)
1355 {
1356 	struct perf_record_stat event;
1357 
1358 	event.header.type = PERF_RECORD_STAT;
1359 	event.header.size = sizeof(event);
1360 	event.header.misc = 0;
1361 
1362 	event.id        = id;
1363 	event.cpu       = cpu;
1364 	event.thread    = thread;
1365 	event.val       = count->val;
1366 	event.ena       = count->ena;
1367 	event.run       = count->run;
1368 
1369 	return process(tool, (union perf_event *) &event, NULL, machine);
1370 }
1371 
1372 int perf_event__synthesize_stat_round(struct perf_tool *tool,
1373 				      u64 evtime, u64 type,
1374 				      perf_event__handler_t process,
1375 				      struct machine *machine)
1376 {
1377 	struct perf_record_stat_round event;
1378 
1379 	event.header.type = PERF_RECORD_STAT_ROUND;
1380 	event.header.size = sizeof(event);
1381 	event.header.misc = 0;
1382 
1383 	event.time = evtime;
1384 	event.type = type;
1385 
1386 	return process(tool, (union perf_event *) &event, NULL, machine);
1387 }
1388 
1389 size_t perf_event__sample_event_size(const struct perf_sample *sample, u64 type, u64 read_format)
1390 {
1391 	size_t sz, result = sizeof(struct perf_record_sample);
1392 
1393 	if (type & PERF_SAMPLE_IDENTIFIER)
1394 		result += sizeof(u64);
1395 
1396 	if (type & PERF_SAMPLE_IP)
1397 		result += sizeof(u64);
1398 
1399 	if (type & PERF_SAMPLE_TID)
1400 		result += sizeof(u64);
1401 
1402 	if (type & PERF_SAMPLE_TIME)
1403 		result += sizeof(u64);
1404 
1405 	if (type & PERF_SAMPLE_ADDR)
1406 		result += sizeof(u64);
1407 
1408 	if (type & PERF_SAMPLE_ID)
1409 		result += sizeof(u64);
1410 
1411 	if (type & PERF_SAMPLE_STREAM_ID)
1412 		result += sizeof(u64);
1413 
1414 	if (type & PERF_SAMPLE_CPU)
1415 		result += sizeof(u64);
1416 
1417 	if (type & PERF_SAMPLE_PERIOD)
1418 		result += sizeof(u64);
1419 
1420 	if (type & PERF_SAMPLE_READ) {
1421 		result += sizeof(u64);
1422 		if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED)
1423 			result += sizeof(u64);
1424 		if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING)
1425 			result += sizeof(u64);
1426 		/* PERF_FORMAT_ID is forced for PERF_SAMPLE_READ */
1427 		if (read_format & PERF_FORMAT_GROUP) {
1428 			sz = sample->read.group.nr *
1429 			     sizeof(struct sample_read_value);
1430 			result += sz;
1431 		} else {
1432 			result += sizeof(u64);
1433 		}
1434 	}
1435 
1436 	if (type & PERF_SAMPLE_CALLCHAIN) {
1437 		sz = (sample->callchain->nr + 1) * sizeof(u64);
1438 		result += sz;
1439 	}
1440 
1441 	if (type & PERF_SAMPLE_RAW) {
1442 		result += sizeof(u32);
1443 		result += sample->raw_size;
1444 	}
1445 
1446 	if (type & PERF_SAMPLE_BRANCH_STACK) {
1447 		sz = sample->branch_stack->nr * sizeof(struct branch_entry);
1448 		/* nr, hw_idx */
1449 		sz += 2 * sizeof(u64);
1450 		result += sz;
1451 	}
1452 
1453 	if (type & PERF_SAMPLE_REGS_USER) {
1454 		if (sample->user_regs.abi) {
1455 			result += sizeof(u64);
1456 			sz = hweight64(sample->user_regs.mask) * sizeof(u64);
1457 			result += sz;
1458 		} else {
1459 			result += sizeof(u64);
1460 		}
1461 	}
1462 
1463 	if (type & PERF_SAMPLE_STACK_USER) {
1464 		sz = sample->user_stack.size;
1465 		result += sizeof(u64);
1466 		if (sz) {
1467 			result += sz;
1468 			result += sizeof(u64);
1469 		}
1470 	}
1471 
1472 	if (type & PERF_SAMPLE_WEIGHT_TYPE)
1473 		result += sizeof(u64);
1474 
1475 	if (type & PERF_SAMPLE_DATA_SRC)
1476 		result += sizeof(u64);
1477 
1478 	if (type & PERF_SAMPLE_TRANSACTION)
1479 		result += sizeof(u64);
1480 
1481 	if (type & PERF_SAMPLE_REGS_INTR) {
1482 		if (sample->intr_regs.abi) {
1483 			result += sizeof(u64);
1484 			sz = hweight64(sample->intr_regs.mask) * sizeof(u64);
1485 			result += sz;
1486 		} else {
1487 			result += sizeof(u64);
1488 		}
1489 	}
1490 
1491 	if (type & PERF_SAMPLE_PHYS_ADDR)
1492 		result += sizeof(u64);
1493 
1494 	if (type & PERF_SAMPLE_CGROUP)
1495 		result += sizeof(u64);
1496 
1497 	if (type & PERF_SAMPLE_DATA_PAGE_SIZE)
1498 		result += sizeof(u64);
1499 
1500 	if (type & PERF_SAMPLE_CODE_PAGE_SIZE)
1501 		result += sizeof(u64);
1502 
1503 	if (type & PERF_SAMPLE_AUX) {
1504 		result += sizeof(u64);
1505 		result += sample->aux_sample.size;
1506 	}
1507 
1508 	return result;
1509 }
1510 
1511 void __weak arch_perf_synthesize_sample_weight(const struct perf_sample *data,
1512 					       __u64 *array, u64 type __maybe_unused)
1513 {
1514 	*array = data->weight;
1515 }
1516 
1517 int perf_event__synthesize_sample(union perf_event *event, u64 type, u64 read_format,
1518 				  const struct perf_sample *sample)
1519 {
1520 	__u64 *array;
1521 	size_t sz;
1522 	/*
1523 	 * used for cross-endian analysis. See git commit 65014ab3
1524 	 * for why this goofiness is needed.
1525 	 */
1526 	union u64_swap u;
1527 
1528 	array = event->sample.array;
1529 
1530 	if (type & PERF_SAMPLE_IDENTIFIER) {
1531 		*array = sample->id;
1532 		array++;
1533 	}
1534 
1535 	if (type & PERF_SAMPLE_IP) {
1536 		*array = sample->ip;
1537 		array++;
1538 	}
1539 
1540 	if (type & PERF_SAMPLE_TID) {
1541 		u.val32[0] = sample->pid;
1542 		u.val32[1] = sample->tid;
1543 		*array = u.val64;
1544 		array++;
1545 	}
1546 
1547 	if (type & PERF_SAMPLE_TIME) {
1548 		*array = sample->time;
1549 		array++;
1550 	}
1551 
1552 	if (type & PERF_SAMPLE_ADDR) {
1553 		*array = sample->addr;
1554 		array++;
1555 	}
1556 
1557 	if (type & PERF_SAMPLE_ID) {
1558 		*array = sample->id;
1559 		array++;
1560 	}
1561 
1562 	if (type & PERF_SAMPLE_STREAM_ID) {
1563 		*array = sample->stream_id;
1564 		array++;
1565 	}
1566 
1567 	if (type & PERF_SAMPLE_CPU) {
1568 		u.val32[0] = sample->cpu;
1569 		u.val32[1] = 0;
1570 		*array = u.val64;
1571 		array++;
1572 	}
1573 
1574 	if (type & PERF_SAMPLE_PERIOD) {
1575 		*array = sample->period;
1576 		array++;
1577 	}
1578 
1579 	if (type & PERF_SAMPLE_READ) {
1580 		if (read_format & PERF_FORMAT_GROUP)
1581 			*array = sample->read.group.nr;
1582 		else
1583 			*array = sample->read.one.value;
1584 		array++;
1585 
1586 		if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) {
1587 			*array = sample->read.time_enabled;
1588 			array++;
1589 		}
1590 
1591 		if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) {
1592 			*array = sample->read.time_running;
1593 			array++;
1594 		}
1595 
1596 		/* PERF_FORMAT_ID is forced for PERF_SAMPLE_READ */
1597 		if (read_format & PERF_FORMAT_GROUP) {
1598 			sz = sample->read.group.nr *
1599 			     sizeof(struct sample_read_value);
1600 			memcpy(array, sample->read.group.values, sz);
1601 			array = (void *)array + sz;
1602 		} else {
1603 			*array = sample->read.one.id;
1604 			array++;
1605 		}
1606 	}
1607 
1608 	if (type & PERF_SAMPLE_CALLCHAIN) {
1609 		sz = (sample->callchain->nr + 1) * sizeof(u64);
1610 		memcpy(array, sample->callchain, sz);
1611 		array = (void *)array + sz;
1612 	}
1613 
1614 	if (type & PERF_SAMPLE_RAW) {
1615 		u.val32[0] = sample->raw_size;
1616 		*array = u.val64;
1617 		array = (void *)array + sizeof(u32);
1618 
1619 		memcpy(array, sample->raw_data, sample->raw_size);
1620 		array = (void *)array + sample->raw_size;
1621 	}
1622 
1623 	if (type & PERF_SAMPLE_BRANCH_STACK) {
1624 		sz = sample->branch_stack->nr * sizeof(struct branch_entry);
1625 		/* nr, hw_idx */
1626 		sz += 2 * sizeof(u64);
1627 		memcpy(array, sample->branch_stack, sz);
1628 		array = (void *)array + sz;
1629 	}
1630 
1631 	if (type & PERF_SAMPLE_REGS_USER) {
1632 		if (sample->user_regs.abi) {
1633 			*array++ = sample->user_regs.abi;
1634 			sz = hweight64(sample->user_regs.mask) * sizeof(u64);
1635 			memcpy(array, sample->user_regs.regs, sz);
1636 			array = (void *)array + sz;
1637 		} else {
1638 			*array++ = 0;
1639 		}
1640 	}
1641 
1642 	if (type & PERF_SAMPLE_STACK_USER) {
1643 		sz = sample->user_stack.size;
1644 		*array++ = sz;
1645 		if (sz) {
1646 			memcpy(array, sample->user_stack.data, sz);
1647 			array = (void *)array + sz;
1648 			*array++ = sz;
1649 		}
1650 	}
1651 
1652 	if (type & PERF_SAMPLE_WEIGHT_TYPE) {
1653 		arch_perf_synthesize_sample_weight(sample, array, type);
1654 		array++;
1655 	}
1656 
1657 	if (type & PERF_SAMPLE_DATA_SRC) {
1658 		*array = sample->data_src;
1659 		array++;
1660 	}
1661 
1662 	if (type & PERF_SAMPLE_TRANSACTION) {
1663 		*array = sample->transaction;
1664 		array++;
1665 	}
1666 
1667 	if (type & PERF_SAMPLE_REGS_INTR) {
1668 		if (sample->intr_regs.abi) {
1669 			*array++ = sample->intr_regs.abi;
1670 			sz = hweight64(sample->intr_regs.mask) * sizeof(u64);
1671 			memcpy(array, sample->intr_regs.regs, sz);
1672 			array = (void *)array + sz;
1673 		} else {
1674 			*array++ = 0;
1675 		}
1676 	}
1677 
1678 	if (type & PERF_SAMPLE_PHYS_ADDR) {
1679 		*array = sample->phys_addr;
1680 		array++;
1681 	}
1682 
1683 	if (type & PERF_SAMPLE_CGROUP) {
1684 		*array = sample->cgroup;
1685 		array++;
1686 	}
1687 
1688 	if (type & PERF_SAMPLE_DATA_PAGE_SIZE) {
1689 		*array = sample->data_page_size;
1690 		array++;
1691 	}
1692 
1693 	if (type & PERF_SAMPLE_CODE_PAGE_SIZE) {
1694 		*array = sample->code_page_size;
1695 		array++;
1696 	}
1697 
1698 	if (type & PERF_SAMPLE_AUX) {
1699 		sz = sample->aux_sample.size;
1700 		*array++ = sz;
1701 		memcpy(array, sample->aux_sample.data, sz);
1702 		array = (void *)array + sz;
1703 	}
1704 
1705 	return 0;
1706 }
1707 
1708 int perf_event__synthesize_id_index(struct perf_tool *tool, perf_event__handler_t process,
1709 				    struct evlist *evlist, struct machine *machine)
1710 {
1711 	union perf_event *ev;
1712 	struct evsel *evsel;
1713 	size_t nr = 0, i = 0, sz, max_nr, n;
1714 	int err;
1715 
1716 	pr_debug2("Synthesizing id index\n");
1717 
1718 	max_nr = (UINT16_MAX - sizeof(struct perf_record_id_index)) /
1719 		 sizeof(struct id_index_entry);
1720 
1721 	evlist__for_each_entry(evlist, evsel)
1722 		nr += evsel->core.ids;
1723 
1724 	n = nr > max_nr ? max_nr : nr;
1725 	sz = sizeof(struct perf_record_id_index) + n * sizeof(struct id_index_entry);
1726 	ev = zalloc(sz);
1727 	if (!ev)
1728 		return -ENOMEM;
1729 
1730 	ev->id_index.header.type = PERF_RECORD_ID_INDEX;
1731 	ev->id_index.header.size = sz;
1732 	ev->id_index.nr = n;
1733 
1734 	evlist__for_each_entry(evlist, evsel) {
1735 		u32 j;
1736 
1737 		for (j = 0; j < evsel->core.ids; j++) {
1738 			struct id_index_entry *e;
1739 			struct perf_sample_id *sid;
1740 
1741 			if (i >= n) {
1742 				err = process(tool, ev, NULL, machine);
1743 				if (err)
1744 					goto out_err;
1745 				nr -= n;
1746 				i = 0;
1747 			}
1748 
1749 			e = &ev->id_index.entries[i++];
1750 
1751 			e->id = evsel->core.id[j];
1752 
1753 			sid = evlist__id2sid(evlist, e->id);
1754 			if (!sid) {
1755 				free(ev);
1756 				return -ENOENT;
1757 			}
1758 
1759 			e->idx = sid->idx;
1760 			e->cpu = sid->cpu;
1761 			e->tid = sid->tid;
1762 		}
1763 	}
1764 
1765 	sz = sizeof(struct perf_record_id_index) + nr * sizeof(struct id_index_entry);
1766 	ev->id_index.header.size = sz;
1767 	ev->id_index.nr = nr;
1768 
1769 	err = process(tool, ev, NULL, machine);
1770 out_err:
1771 	free(ev);
1772 
1773 	return err;
1774 }
1775 
1776 int __machine__synthesize_threads(struct machine *machine, struct perf_tool *tool,
1777 				  struct target *target, struct perf_thread_map *threads,
1778 				  perf_event__handler_t process, bool data_mmap,
1779 				  unsigned int nr_threads_synthesize)
1780 {
1781 	if (target__has_task(target))
1782 		return perf_event__synthesize_thread_map(tool, threads, process, machine, data_mmap);
1783 	else if (target__has_cpu(target))
1784 		return perf_event__synthesize_threads(tool, process,
1785 						      machine, data_mmap,
1786 						      nr_threads_synthesize);
1787 	/* command specified */
1788 	return 0;
1789 }
1790 
1791 int machine__synthesize_threads(struct machine *machine, struct target *target,
1792 				struct perf_thread_map *threads, bool data_mmap,
1793 				unsigned int nr_threads_synthesize)
1794 {
1795 	return __machine__synthesize_threads(machine, NULL, target, threads,
1796 					     perf_event__process, data_mmap,
1797 					     nr_threads_synthesize);
1798 }
1799 
1800 static struct perf_record_event_update *event_update_event__new(size_t size, u64 type, u64 id)
1801 {
1802 	struct perf_record_event_update *ev;
1803 
1804 	size += sizeof(*ev);
1805 	size  = PERF_ALIGN(size, sizeof(u64));
1806 
1807 	ev = zalloc(size);
1808 	if (ev) {
1809 		ev->header.type = PERF_RECORD_EVENT_UPDATE;
1810 		ev->header.size = (u16)size;
1811 		ev->type	= type;
1812 		ev->id		= id;
1813 	}
1814 	return ev;
1815 }
1816 
1817 int perf_event__synthesize_event_update_unit(struct perf_tool *tool, struct evsel *evsel,
1818 					     perf_event__handler_t process)
1819 {
1820 	size_t size = strlen(evsel->unit);
1821 	struct perf_record_event_update *ev;
1822 	int err;
1823 
1824 	ev = event_update_event__new(size + 1, PERF_EVENT_UPDATE__UNIT, evsel->core.id[0]);
1825 	if (ev == NULL)
1826 		return -ENOMEM;
1827 
1828 	strlcpy(ev->data, evsel->unit, size + 1);
1829 	err = process(tool, (union perf_event *)ev, NULL, NULL);
1830 	free(ev);
1831 	return err;
1832 }
1833 
1834 int perf_event__synthesize_event_update_scale(struct perf_tool *tool, struct evsel *evsel,
1835 					      perf_event__handler_t process)
1836 {
1837 	struct perf_record_event_update *ev;
1838 	struct perf_record_event_update_scale *ev_data;
1839 	int err;
1840 
1841 	ev = event_update_event__new(sizeof(*ev_data), PERF_EVENT_UPDATE__SCALE, evsel->core.id[0]);
1842 	if (ev == NULL)
1843 		return -ENOMEM;
1844 
1845 	ev_data = (struct perf_record_event_update_scale *)ev->data;
1846 	ev_data->scale = evsel->scale;
1847 	err = process(tool, (union perf_event *)ev, NULL, NULL);
1848 	free(ev);
1849 	return err;
1850 }
1851 
1852 int perf_event__synthesize_event_update_name(struct perf_tool *tool, struct evsel *evsel,
1853 					     perf_event__handler_t process)
1854 {
1855 	struct perf_record_event_update *ev;
1856 	size_t len = strlen(evsel->name);
1857 	int err;
1858 
1859 	ev = event_update_event__new(len + 1, PERF_EVENT_UPDATE__NAME, evsel->core.id[0]);
1860 	if (ev == NULL)
1861 		return -ENOMEM;
1862 
1863 	strlcpy(ev->data, evsel->name, len + 1);
1864 	err = process(tool, (union perf_event *)ev, NULL, NULL);
1865 	free(ev);
1866 	return err;
1867 }
1868 
1869 int perf_event__synthesize_event_update_cpus(struct perf_tool *tool, struct evsel *evsel,
1870 					     perf_event__handler_t process)
1871 {
1872 	size_t size = sizeof(struct perf_record_event_update);
1873 	struct perf_record_event_update *ev;
1874 	int max, err;
1875 	u16 type;
1876 
1877 	if (!evsel->core.own_cpus)
1878 		return 0;
1879 
1880 	ev = cpu_map_data__alloc(evsel->core.own_cpus, &size, &type, &max);
1881 	if (!ev)
1882 		return -ENOMEM;
1883 
1884 	ev->header.type = PERF_RECORD_EVENT_UPDATE;
1885 	ev->header.size = (u16)size;
1886 	ev->type	= PERF_EVENT_UPDATE__CPUS;
1887 	ev->id		= evsel->core.id[0];
1888 
1889 	cpu_map_data__synthesize((struct perf_record_cpu_map_data *)ev->data,
1890 				 evsel->core.own_cpus, type, max);
1891 
1892 	err = process(tool, (union perf_event *)ev, NULL, NULL);
1893 	free(ev);
1894 	return err;
1895 }
1896 
1897 int perf_event__synthesize_attrs(struct perf_tool *tool, struct evlist *evlist,
1898 				 perf_event__handler_t process)
1899 {
1900 	struct evsel *evsel;
1901 	int err = 0;
1902 
1903 	evlist__for_each_entry(evlist, evsel) {
1904 		err = perf_event__synthesize_attr(tool, &evsel->core.attr, evsel->core.ids,
1905 						  evsel->core.id, process);
1906 		if (err) {
1907 			pr_debug("failed to create perf header attribute\n");
1908 			return err;
1909 		}
1910 	}
1911 
1912 	return err;
1913 }
1914 
1915 static bool has_unit(struct evsel *evsel)
1916 {
1917 	return evsel->unit && *evsel->unit;
1918 }
1919 
1920 static bool has_scale(struct evsel *evsel)
1921 {
1922 	return evsel->scale != 1;
1923 }
1924 
1925 int perf_event__synthesize_extra_attr(struct perf_tool *tool, struct evlist *evsel_list,
1926 				      perf_event__handler_t process, bool is_pipe)
1927 {
1928 	struct evsel *evsel;
1929 	int err;
1930 
1931 	/*
1932 	 * Synthesize other events stuff not carried within
1933 	 * attr event - unit, scale, name
1934 	 */
1935 	evlist__for_each_entry(evsel_list, evsel) {
1936 		if (!evsel->supported)
1937 			continue;
1938 
1939 		/*
1940 		 * Synthesize unit and scale only if it's defined.
1941 		 */
1942 		if (has_unit(evsel)) {
1943 			err = perf_event__synthesize_event_update_unit(tool, evsel, process);
1944 			if (err < 0) {
1945 				pr_err("Couldn't synthesize evsel unit.\n");
1946 				return err;
1947 			}
1948 		}
1949 
1950 		if (has_scale(evsel)) {
1951 			err = perf_event__synthesize_event_update_scale(tool, evsel, process);
1952 			if (err < 0) {
1953 				pr_err("Couldn't synthesize evsel evsel.\n");
1954 				return err;
1955 			}
1956 		}
1957 
1958 		if (evsel->core.own_cpus) {
1959 			err = perf_event__synthesize_event_update_cpus(tool, evsel, process);
1960 			if (err < 0) {
1961 				pr_err("Couldn't synthesize evsel cpus.\n");
1962 				return err;
1963 			}
1964 		}
1965 
1966 		/*
1967 		 * Name is needed only for pipe output,
1968 		 * perf.data carries event names.
1969 		 */
1970 		if (is_pipe) {
1971 			err = perf_event__synthesize_event_update_name(tool, evsel, process);
1972 			if (err < 0) {
1973 				pr_err("Couldn't synthesize evsel name.\n");
1974 				return err;
1975 			}
1976 		}
1977 	}
1978 	return 0;
1979 }
1980 
1981 int perf_event__synthesize_attr(struct perf_tool *tool, struct perf_event_attr *attr,
1982 				u32 ids, u64 *id, perf_event__handler_t process)
1983 {
1984 	union perf_event *ev;
1985 	size_t size;
1986 	int err;
1987 
1988 	size = sizeof(struct perf_event_attr);
1989 	size = PERF_ALIGN(size, sizeof(u64));
1990 	size += sizeof(struct perf_event_header);
1991 	size += ids * sizeof(u64);
1992 
1993 	ev = zalloc(size);
1994 
1995 	if (ev == NULL)
1996 		return -ENOMEM;
1997 
1998 	ev->attr.attr = *attr;
1999 	memcpy(ev->attr.id, id, ids * sizeof(u64));
2000 
2001 	ev->attr.header.type = PERF_RECORD_HEADER_ATTR;
2002 	ev->attr.header.size = (u16)size;
2003 
2004 	if (ev->attr.header.size == size)
2005 		err = process(tool, ev, NULL, NULL);
2006 	else
2007 		err = -E2BIG;
2008 
2009 	free(ev);
2010 
2011 	return err;
2012 }
2013 
2014 int perf_event__synthesize_tracing_data(struct perf_tool *tool, int fd, struct evlist *evlist,
2015 					perf_event__handler_t process)
2016 {
2017 	union perf_event ev;
2018 	struct tracing_data *tdata;
2019 	ssize_t size = 0, aligned_size = 0, padding;
2020 	struct feat_fd ff;
2021 
2022 	/*
2023 	 * We are going to store the size of the data followed
2024 	 * by the data contents. Since the fd descriptor is a pipe,
2025 	 * we cannot seek back to store the size of the data once
2026 	 * we know it. Instead we:
2027 	 *
2028 	 * - write the tracing data to the temp file
2029 	 * - get/write the data size to pipe
2030 	 * - write the tracing data from the temp file
2031 	 *   to the pipe
2032 	 */
2033 	tdata = tracing_data_get(&evlist->core.entries, fd, true);
2034 	if (!tdata)
2035 		return -1;
2036 
2037 	memset(&ev, 0, sizeof(ev));
2038 
2039 	ev.tracing_data.header.type = PERF_RECORD_HEADER_TRACING_DATA;
2040 	size = tdata->size;
2041 	aligned_size = PERF_ALIGN(size, sizeof(u64));
2042 	padding = aligned_size - size;
2043 	ev.tracing_data.header.size = sizeof(ev.tracing_data);
2044 	ev.tracing_data.size = aligned_size;
2045 
2046 	process(tool, &ev, NULL, NULL);
2047 
2048 	/*
2049 	 * The put function will copy all the tracing data
2050 	 * stored in temp file to the pipe.
2051 	 */
2052 	tracing_data_put(tdata);
2053 
2054 	ff = (struct feat_fd){ .fd = fd };
2055 	if (write_padded(&ff, NULL, 0, padding))
2056 		return -1;
2057 
2058 	return aligned_size;
2059 }
2060 
2061 int perf_event__synthesize_build_id(struct perf_tool *tool, struct dso *pos, u16 misc,
2062 				    perf_event__handler_t process, struct machine *machine)
2063 {
2064 	union perf_event ev;
2065 	size_t len;
2066 
2067 	if (!pos->hit)
2068 		return 0;
2069 
2070 	memset(&ev, 0, sizeof(ev));
2071 
2072 	len = pos->long_name_len + 1;
2073 	len = PERF_ALIGN(len, NAME_ALIGN);
2074 	memcpy(&ev.build_id.build_id, pos->bid.data, sizeof(pos->bid.data));
2075 	ev.build_id.header.type = PERF_RECORD_HEADER_BUILD_ID;
2076 	ev.build_id.header.misc = misc;
2077 	ev.build_id.pid = machine->pid;
2078 	ev.build_id.header.size = sizeof(ev.build_id) + len;
2079 	memcpy(&ev.build_id.filename, pos->long_name, pos->long_name_len);
2080 
2081 	return process(tool, &ev, NULL, machine);
2082 }
2083 
2084 int perf_event__synthesize_stat_events(struct perf_stat_config *config, struct perf_tool *tool,
2085 				       struct evlist *evlist, perf_event__handler_t process, bool attrs)
2086 {
2087 	int err;
2088 
2089 	if (attrs) {
2090 		err = perf_event__synthesize_attrs(tool, evlist, process);
2091 		if (err < 0) {
2092 			pr_err("Couldn't synthesize attrs.\n");
2093 			return err;
2094 		}
2095 	}
2096 
2097 	err = perf_event__synthesize_extra_attr(tool, evlist, process, attrs);
2098 	err = perf_event__synthesize_thread_map2(tool, evlist->core.threads, process, NULL);
2099 	if (err < 0) {
2100 		pr_err("Couldn't synthesize thread map.\n");
2101 		return err;
2102 	}
2103 
2104 	err = perf_event__synthesize_cpu_map(tool, evlist->core.cpus, process, NULL);
2105 	if (err < 0) {
2106 		pr_err("Couldn't synthesize thread map.\n");
2107 		return err;
2108 	}
2109 
2110 	err = perf_event__synthesize_stat_config(tool, config, process, NULL);
2111 	if (err < 0) {
2112 		pr_err("Couldn't synthesize config.\n");
2113 		return err;
2114 	}
2115 
2116 	return 0;
2117 }
2118 
2119 extern const struct perf_header_feature_ops feat_ops[HEADER_LAST_FEATURE];
2120 
2121 int perf_event__synthesize_features(struct perf_tool *tool, struct perf_session *session,
2122 				    struct evlist *evlist, perf_event__handler_t process)
2123 {
2124 	struct perf_header *header = &session->header;
2125 	struct perf_record_header_feature *fe;
2126 	struct feat_fd ff;
2127 	size_t sz, sz_hdr;
2128 	int feat, ret;
2129 
2130 	sz_hdr = sizeof(fe->header);
2131 	sz = sizeof(union perf_event);
2132 	/* get a nice alignment */
2133 	sz = PERF_ALIGN(sz, page_size);
2134 
2135 	memset(&ff, 0, sizeof(ff));
2136 
2137 	ff.buf = malloc(sz);
2138 	if (!ff.buf)
2139 		return -ENOMEM;
2140 
2141 	ff.size = sz - sz_hdr;
2142 	ff.ph = &session->header;
2143 
2144 	for_each_set_bit(feat, header->adds_features, HEADER_FEAT_BITS) {
2145 		if (!feat_ops[feat].synthesize) {
2146 			pr_debug("No record header feature for header :%d\n", feat);
2147 			continue;
2148 		}
2149 
2150 		ff.offset = sizeof(*fe);
2151 
2152 		ret = feat_ops[feat].write(&ff, evlist);
2153 		if (ret || ff.offset <= (ssize_t)sizeof(*fe)) {
2154 			pr_debug("Error writing feature\n");
2155 			continue;
2156 		}
2157 		/* ff.buf may have changed due to realloc in do_write() */
2158 		fe = ff.buf;
2159 		memset(fe, 0, sizeof(*fe));
2160 
2161 		fe->feat_id = feat;
2162 		fe->header.type = PERF_RECORD_HEADER_FEATURE;
2163 		fe->header.size = ff.offset;
2164 
2165 		ret = process(tool, ff.buf, NULL, NULL);
2166 		if (ret) {
2167 			free(ff.buf);
2168 			return ret;
2169 		}
2170 	}
2171 
2172 	/* Send HEADER_LAST_FEATURE mark. */
2173 	fe = ff.buf;
2174 	fe->feat_id     = HEADER_LAST_FEATURE;
2175 	fe->header.type = PERF_RECORD_HEADER_FEATURE;
2176 	fe->header.size = sizeof(*fe);
2177 
2178 	ret = process(tool, ff.buf, NULL, NULL);
2179 
2180 	free(ff.buf);
2181 	return ret;
2182 }
2183 
2184 int perf_event__synthesize_for_pipe(struct perf_tool *tool,
2185 				    struct perf_session *session,
2186 				    struct perf_data *data,
2187 				    perf_event__handler_t process)
2188 {
2189 	int err;
2190 	int ret = 0;
2191 	struct evlist *evlist = session->evlist;
2192 
2193 	/*
2194 	 * We need to synthesize events first, because some
2195 	 * features works on top of them (on report side).
2196 	 */
2197 	err = perf_event__synthesize_attrs(tool, evlist, process);
2198 	if (err < 0) {
2199 		pr_err("Couldn't synthesize attrs.\n");
2200 		return err;
2201 	}
2202 	ret += err;
2203 
2204 	err = perf_event__synthesize_features(tool, session, evlist, process);
2205 	if (err < 0) {
2206 		pr_err("Couldn't synthesize features.\n");
2207 		return err;
2208 	}
2209 	ret += err;
2210 
2211 	if (have_tracepoints(&evlist->core.entries)) {
2212 		int fd = perf_data__fd(data);
2213 
2214 		/*
2215 		 * FIXME err <= 0 here actually means that
2216 		 * there were no tracepoints so its not really
2217 		 * an error, just that we don't need to
2218 		 * synthesize anything.  We really have to
2219 		 * return this more properly and also
2220 		 * propagate errors that now are calling die()
2221 		 */
2222 		err = perf_event__synthesize_tracing_data(tool,	fd, evlist,
2223 							  process);
2224 		if (err <= 0) {
2225 			pr_err("Couldn't record tracing data.\n");
2226 			return err;
2227 		}
2228 		ret += err;
2229 	}
2230 
2231 	return ret;
2232 }
2233