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,
719 				      bool needs_mmap, bool mmap_data)
720 {
721 	char filename[PATH_MAX];
722 	struct dirent **dirent;
723 	pid_t tgid, ppid;
724 	int rc = 0;
725 	int i, n;
726 
727 	/* special case: only send one comm event using passed in pid */
728 	if (!full) {
729 		tgid = perf_event__synthesize_comm(tool, comm_event, pid,
730 						   process, machine);
731 
732 		if (tgid == -1)
733 			return -1;
734 
735 		if (perf_event__synthesize_namespaces(tool, namespaces_event, pid,
736 						      tgid, process, machine) < 0)
737 			return -1;
738 
739 		/*
740 		 * send mmap only for thread group leader
741 		 * see thread__init_maps()
742 		 */
743 		if (pid == tgid && needs_mmap &&
744 		    perf_event__synthesize_mmap_events(tool, mmap_event, pid, tgid,
745 						       process, machine, mmap_data))
746 			return -1;
747 
748 		return 0;
749 	}
750 
751 	if (machine__is_default_guest(machine))
752 		return 0;
753 
754 	snprintf(filename, sizeof(filename), "%s/proc/%d/task",
755 		 machine->root_dir, pid);
756 
757 	n = scandir(filename, &dirent, filter_task, NULL);
758 	if (n < 0)
759 		return n;
760 
761 	for (i = 0; i < n; i++) {
762 		char *end;
763 		pid_t _pid;
764 		bool kernel_thread = false;
765 
766 		_pid = strtol(dirent[i]->d_name, &end, 10);
767 		if (*end)
768 			continue;
769 
770 		/* some threads may exit just after scan, ignore it */
771 		if (perf_event__prepare_comm(comm_event, pid, _pid, machine,
772 					     &tgid, &ppid, &kernel_thread) != 0)
773 			continue;
774 
775 		rc = -1;
776 		if (perf_event__synthesize_fork(tool, fork_event, _pid, tgid,
777 						ppid, process, machine) < 0)
778 			break;
779 
780 		if (perf_event__synthesize_namespaces(tool, namespaces_event, _pid,
781 						      tgid, process, machine) < 0)
782 			break;
783 
784 		/*
785 		 * Send the prepared comm event
786 		 */
787 		if (perf_tool__process_synth_event(tool, comm_event, machine, process) != 0)
788 			break;
789 
790 		rc = 0;
791 		if (_pid == pid && !kernel_thread && needs_mmap) {
792 			/* process the parent's maps too */
793 			rc = perf_event__synthesize_mmap_events(tool, mmap_event, pid, tgid,
794 						process, machine, mmap_data);
795 			if (rc)
796 				break;
797 		}
798 	}
799 
800 	for (i = 0; i < n; i++)
801 		zfree(&dirent[i]);
802 	free(dirent);
803 
804 	return rc;
805 }
806 
807 int perf_event__synthesize_thread_map(struct perf_tool *tool,
808 				      struct perf_thread_map *threads,
809 				      perf_event__handler_t process,
810 				      struct machine *machine,
811 				      bool needs_mmap, bool mmap_data)
812 {
813 	union perf_event *comm_event, *mmap_event, *fork_event;
814 	union perf_event *namespaces_event;
815 	int err = -1, thread, j;
816 
817 	comm_event = malloc(sizeof(comm_event->comm) + machine->id_hdr_size);
818 	if (comm_event == NULL)
819 		goto out;
820 
821 	mmap_event = malloc(sizeof(mmap_event->mmap2) + machine->id_hdr_size);
822 	if (mmap_event == NULL)
823 		goto out_free_comm;
824 
825 	fork_event = malloc(sizeof(fork_event->fork) + machine->id_hdr_size);
826 	if (fork_event == NULL)
827 		goto out_free_mmap;
828 
829 	namespaces_event = malloc(sizeof(namespaces_event->namespaces) +
830 				  (NR_NAMESPACES * sizeof(struct perf_ns_link_info)) +
831 				  machine->id_hdr_size);
832 	if (namespaces_event == NULL)
833 		goto out_free_fork;
834 
835 	err = 0;
836 	for (thread = 0; thread < threads->nr; ++thread) {
837 		if (__event__synthesize_thread(comm_event, mmap_event,
838 					       fork_event, namespaces_event,
839 					       perf_thread_map__pid(threads, thread), 0,
840 					       process, tool, machine,
841 					       needs_mmap, mmap_data)) {
842 			err = -1;
843 			break;
844 		}
845 
846 		/*
847 		 * comm.pid is set to thread group id by
848 		 * perf_event__synthesize_comm
849 		 */
850 		if ((int) comm_event->comm.pid != perf_thread_map__pid(threads, thread)) {
851 			bool need_leader = true;
852 
853 			/* is thread group leader in thread_map? */
854 			for (j = 0; j < threads->nr; ++j) {
855 				if ((int) comm_event->comm.pid == perf_thread_map__pid(threads, j)) {
856 					need_leader = false;
857 					break;
858 				}
859 			}
860 
861 			/* if not, generate events for it */
862 			if (need_leader &&
863 			    __event__synthesize_thread(comm_event, mmap_event,
864 						       fork_event, namespaces_event,
865 						       comm_event->comm.pid, 0,
866 						       process, tool, machine,
867 						       needs_mmap, mmap_data)) {
868 				err = -1;
869 				break;
870 			}
871 		}
872 	}
873 	free(namespaces_event);
874 out_free_fork:
875 	free(fork_event);
876 out_free_mmap:
877 	free(mmap_event);
878 out_free_comm:
879 	free(comm_event);
880 out:
881 	return err;
882 }
883 
884 static int __perf_event__synthesize_threads(struct perf_tool *tool,
885 					    perf_event__handler_t process,
886 					    struct machine *machine,
887 					    bool needs_mmap,
888 					    bool mmap_data,
889 					    struct dirent **dirent,
890 					    int start,
891 					    int num)
892 {
893 	union perf_event *comm_event, *mmap_event, *fork_event;
894 	union perf_event *namespaces_event;
895 	int err = -1;
896 	char *end;
897 	pid_t pid;
898 	int i;
899 
900 	comm_event = malloc(sizeof(comm_event->comm) + machine->id_hdr_size);
901 	if (comm_event == NULL)
902 		goto out;
903 
904 	mmap_event = malloc(sizeof(mmap_event->mmap2) + machine->id_hdr_size);
905 	if (mmap_event == NULL)
906 		goto out_free_comm;
907 
908 	fork_event = malloc(sizeof(fork_event->fork) + machine->id_hdr_size);
909 	if (fork_event == NULL)
910 		goto out_free_mmap;
911 
912 	namespaces_event = malloc(sizeof(namespaces_event->namespaces) +
913 				  (NR_NAMESPACES * sizeof(struct perf_ns_link_info)) +
914 				  machine->id_hdr_size);
915 	if (namespaces_event == NULL)
916 		goto out_free_fork;
917 
918 	for (i = start; i < start + num; i++) {
919 		if (!isdigit(dirent[i]->d_name[0]))
920 			continue;
921 
922 		pid = (pid_t)strtol(dirent[i]->d_name, &end, 10);
923 		/* only interested in proper numerical dirents */
924 		if (*end)
925 			continue;
926 		/*
927 		 * We may race with exiting thread, so don't stop just because
928 		 * one thread couldn't be synthesized.
929 		 */
930 		__event__synthesize_thread(comm_event, mmap_event, fork_event,
931 					   namespaces_event, pid, 1, process,
932 					   tool, machine, needs_mmap, mmap_data);
933 	}
934 	err = 0;
935 
936 	free(namespaces_event);
937 out_free_fork:
938 	free(fork_event);
939 out_free_mmap:
940 	free(mmap_event);
941 out_free_comm:
942 	free(comm_event);
943 out:
944 	return err;
945 }
946 
947 struct synthesize_threads_arg {
948 	struct perf_tool *tool;
949 	perf_event__handler_t process;
950 	struct machine *machine;
951 	bool needs_mmap;
952 	bool mmap_data;
953 	struct dirent **dirent;
954 	int num;
955 	int start;
956 };
957 
958 static void *synthesize_threads_worker(void *arg)
959 {
960 	struct synthesize_threads_arg *args = arg;
961 
962 	__perf_event__synthesize_threads(args->tool, args->process,
963 					 args->machine,
964 					 args->needs_mmap, args->mmap_data,
965 					 args->dirent,
966 					 args->start, args->num);
967 	return NULL;
968 }
969 
970 int perf_event__synthesize_threads(struct perf_tool *tool,
971 				   perf_event__handler_t process,
972 				   struct machine *machine,
973 				   bool needs_mmap, bool mmap_data,
974 				   unsigned int nr_threads_synthesize)
975 {
976 	struct synthesize_threads_arg *args = NULL;
977 	pthread_t *synthesize_threads = NULL;
978 	char proc_path[PATH_MAX];
979 	struct dirent **dirent;
980 	int num_per_thread;
981 	int m, n, i, j;
982 	int thread_nr;
983 	int base = 0;
984 	int err = -1;
985 
986 
987 	if (machine__is_default_guest(machine))
988 		return 0;
989 
990 	snprintf(proc_path, sizeof(proc_path), "%s/proc", machine->root_dir);
991 	n = scandir(proc_path, &dirent, filter_task, NULL);
992 	if (n < 0)
993 		return err;
994 
995 	if (nr_threads_synthesize == UINT_MAX)
996 		thread_nr = sysconf(_SC_NPROCESSORS_ONLN);
997 	else
998 		thread_nr = nr_threads_synthesize;
999 
1000 	if (thread_nr <= 1) {
1001 		err = __perf_event__synthesize_threads(tool, process,
1002 						       machine,
1003 						       needs_mmap, mmap_data,
1004 						       dirent, base, n);
1005 		goto free_dirent;
1006 	}
1007 	if (thread_nr > n)
1008 		thread_nr = n;
1009 
1010 	synthesize_threads = calloc(sizeof(pthread_t), thread_nr);
1011 	if (synthesize_threads == NULL)
1012 		goto free_dirent;
1013 
1014 	args = calloc(sizeof(*args), thread_nr);
1015 	if (args == NULL)
1016 		goto free_threads;
1017 
1018 	num_per_thread = n / thread_nr;
1019 	m = n % thread_nr;
1020 	for (i = 0; i < thread_nr; i++) {
1021 		args[i].tool = tool;
1022 		args[i].process = process;
1023 		args[i].machine = machine;
1024 		args[i].needs_mmap = needs_mmap;
1025 		args[i].mmap_data = mmap_data;
1026 		args[i].dirent = dirent;
1027 	}
1028 	for (i = 0; i < m; i++) {
1029 		args[i].num = num_per_thread + 1;
1030 		args[i].start = i * args[i].num;
1031 	}
1032 	if (i != 0)
1033 		base = args[i-1].start + args[i-1].num;
1034 	for (j = i; j < thread_nr; j++) {
1035 		args[j].num = num_per_thread;
1036 		args[j].start = base + (j - i) * args[i].num;
1037 	}
1038 
1039 	for (i = 0; i < thread_nr; i++) {
1040 		if (pthread_create(&synthesize_threads[i], NULL,
1041 				   synthesize_threads_worker, &args[i]))
1042 			goto out_join;
1043 	}
1044 	err = 0;
1045 out_join:
1046 	for (i = 0; i < thread_nr; i++)
1047 		pthread_join(synthesize_threads[i], NULL);
1048 	free(args);
1049 free_threads:
1050 	free(synthesize_threads);
1051 free_dirent:
1052 	for (i = 0; i < n; i++)
1053 		zfree(&dirent[i]);
1054 	free(dirent);
1055 
1056 	return err;
1057 }
1058 
1059 int __weak perf_event__synthesize_extra_kmaps(struct perf_tool *tool __maybe_unused,
1060 					      perf_event__handler_t process __maybe_unused,
1061 					      struct machine *machine __maybe_unused)
1062 {
1063 	return 0;
1064 }
1065 
1066 static int __perf_event__synthesize_kernel_mmap(struct perf_tool *tool,
1067 						perf_event__handler_t process,
1068 						struct machine *machine)
1069 {
1070 	union perf_event *event;
1071 	size_t size = symbol_conf.buildid_mmap2 ?
1072 			sizeof(event->mmap2) : sizeof(event->mmap);
1073 	struct map *map = machine__kernel_map(machine);
1074 	struct kmap *kmap;
1075 	int err;
1076 
1077 	if (map == NULL)
1078 		return -1;
1079 
1080 	kmap = map__kmap(map);
1081 	if (!kmap->ref_reloc_sym)
1082 		return -1;
1083 
1084 	/*
1085 	 * We should get this from /sys/kernel/sections/.text, but till that is
1086 	 * available use this, and after it is use this as a fallback for older
1087 	 * kernels.
1088 	 */
1089 	event = zalloc(size + machine->id_hdr_size);
1090 	if (event == NULL) {
1091 		pr_debug("Not enough memory synthesizing mmap event "
1092 			 "for kernel modules\n");
1093 		return -1;
1094 	}
1095 
1096 	if (machine__is_host(machine)) {
1097 		/*
1098 		 * kernel uses PERF_RECORD_MISC_USER for user space maps,
1099 		 * see kernel/perf_event.c __perf_event_mmap
1100 		 */
1101 		event->header.misc = PERF_RECORD_MISC_KERNEL;
1102 	} else {
1103 		event->header.misc = PERF_RECORD_MISC_GUEST_KERNEL;
1104 	}
1105 
1106 	if (symbol_conf.buildid_mmap2) {
1107 		size = snprintf(event->mmap2.filename, sizeof(event->mmap2.filename),
1108 				"%s%s", machine->mmap_name, kmap->ref_reloc_sym->name) + 1;
1109 		size = PERF_ALIGN(size, sizeof(u64));
1110 		event->mmap2.header.type = PERF_RECORD_MMAP2;
1111 		event->mmap2.header.size = (sizeof(event->mmap2) -
1112 				(sizeof(event->mmap2.filename) - size) + machine->id_hdr_size);
1113 		event->mmap2.pgoff = kmap->ref_reloc_sym->addr;
1114 		event->mmap2.start = map->start;
1115 		event->mmap2.len   = map->end - event->mmap.start;
1116 		event->mmap2.pid   = machine->pid;
1117 
1118 		perf_record_mmap2__read_build_id(&event->mmap2, true);
1119 	} else {
1120 		size = snprintf(event->mmap.filename, sizeof(event->mmap.filename),
1121 				"%s%s", machine->mmap_name, kmap->ref_reloc_sym->name) + 1;
1122 		size = PERF_ALIGN(size, sizeof(u64));
1123 		event->mmap.header.type = PERF_RECORD_MMAP;
1124 		event->mmap.header.size = (sizeof(event->mmap) -
1125 				(sizeof(event->mmap.filename) - size) + machine->id_hdr_size);
1126 		event->mmap.pgoff = kmap->ref_reloc_sym->addr;
1127 		event->mmap.start = map->start;
1128 		event->mmap.len   = map->end - event->mmap.start;
1129 		event->mmap.pid   = machine->pid;
1130 	}
1131 
1132 	err = perf_tool__process_synth_event(tool, event, machine, process);
1133 	free(event);
1134 
1135 	return err;
1136 }
1137 
1138 int perf_event__synthesize_kernel_mmap(struct perf_tool *tool,
1139 				       perf_event__handler_t process,
1140 				       struct machine *machine)
1141 {
1142 	int err;
1143 
1144 	err = __perf_event__synthesize_kernel_mmap(tool, process, machine);
1145 	if (err < 0)
1146 		return err;
1147 
1148 	return perf_event__synthesize_extra_kmaps(tool, process, machine);
1149 }
1150 
1151 int perf_event__synthesize_thread_map2(struct perf_tool *tool,
1152 				      struct perf_thread_map *threads,
1153 				      perf_event__handler_t process,
1154 				      struct machine *machine)
1155 {
1156 	union perf_event *event;
1157 	int i, err, size;
1158 
1159 	size  = sizeof(event->thread_map);
1160 	size +=	threads->nr * sizeof(event->thread_map.entries[0]);
1161 
1162 	event = zalloc(size);
1163 	if (!event)
1164 		return -ENOMEM;
1165 
1166 	event->header.type = PERF_RECORD_THREAD_MAP;
1167 	event->header.size = size;
1168 	event->thread_map.nr = threads->nr;
1169 
1170 	for (i = 0; i < threads->nr; i++) {
1171 		struct perf_record_thread_map_entry *entry = &event->thread_map.entries[i];
1172 		char *comm = perf_thread_map__comm(threads, i);
1173 
1174 		if (!comm)
1175 			comm = (char *) "";
1176 
1177 		entry->pid = perf_thread_map__pid(threads, i);
1178 		strncpy((char *) &entry->comm, comm, sizeof(entry->comm));
1179 	}
1180 
1181 	err = process(tool, event, NULL, machine);
1182 
1183 	free(event);
1184 	return err;
1185 }
1186 
1187 static void synthesize_cpus(struct cpu_map_entries *cpus,
1188 			    struct perf_cpu_map *map)
1189 {
1190 	int i, map_nr = perf_cpu_map__nr(map);
1191 
1192 	cpus->nr = map_nr;
1193 
1194 	for (i = 0; i < map_nr; i++)
1195 		cpus->cpu[i] = perf_cpu_map__cpu(map, i).cpu;
1196 }
1197 
1198 static void synthesize_mask(struct perf_record_record_cpu_map *mask,
1199 			    struct perf_cpu_map *map, int max)
1200 {
1201 	int i;
1202 
1203 	mask->nr = BITS_TO_LONGS(max);
1204 	mask->long_size = sizeof(long);
1205 
1206 	for (i = 0; i < perf_cpu_map__nr(map); i++)
1207 		set_bit(perf_cpu_map__cpu(map, i).cpu, mask->mask);
1208 }
1209 
1210 static size_t cpus_size(struct perf_cpu_map *map)
1211 {
1212 	return sizeof(struct cpu_map_entries) + perf_cpu_map__nr(map) * sizeof(u16);
1213 }
1214 
1215 static size_t mask_size(struct perf_cpu_map *map, int *max)
1216 {
1217 	int i;
1218 
1219 	*max = 0;
1220 
1221 	for (i = 0; i < perf_cpu_map__nr(map); i++) {
1222 		/* bit position of the cpu is + 1 */
1223 		int bit = perf_cpu_map__cpu(map, i).cpu + 1;
1224 
1225 		if (bit > *max)
1226 			*max = bit;
1227 	}
1228 
1229 	return sizeof(struct perf_record_record_cpu_map) + BITS_TO_LONGS(*max) * sizeof(long);
1230 }
1231 
1232 void *cpu_map_data__alloc(struct perf_cpu_map *map, size_t *size, u16 *type, int *max)
1233 {
1234 	size_t size_cpus, size_mask;
1235 	bool is_dummy = perf_cpu_map__empty(map);
1236 
1237 	/*
1238 	 * Both array and mask data have variable size based
1239 	 * on the number of cpus and their actual values.
1240 	 * The size of the 'struct perf_record_cpu_map_data' is:
1241 	 *
1242 	 *   array = size of 'struct cpu_map_entries' +
1243 	 *           number of cpus * sizeof(u64)
1244 	 *
1245 	 *   mask  = size of 'struct perf_record_record_cpu_map' +
1246 	 *           maximum cpu bit converted to size of longs
1247 	 *
1248 	 * and finally + the size of 'struct perf_record_cpu_map_data'.
1249 	 */
1250 	size_cpus = cpus_size(map);
1251 	size_mask = mask_size(map, max);
1252 
1253 	if (is_dummy || (size_cpus < size_mask)) {
1254 		*size += size_cpus;
1255 		*type  = PERF_CPU_MAP__CPUS;
1256 	} else {
1257 		*size += size_mask;
1258 		*type  = PERF_CPU_MAP__MASK;
1259 	}
1260 
1261 	*size += sizeof(struct perf_record_cpu_map_data);
1262 	*size = PERF_ALIGN(*size, sizeof(u64));
1263 	return zalloc(*size);
1264 }
1265 
1266 void cpu_map_data__synthesize(struct perf_record_cpu_map_data *data, struct perf_cpu_map *map,
1267 			      u16 type, int max)
1268 {
1269 	data->type = type;
1270 
1271 	switch (type) {
1272 	case PERF_CPU_MAP__CPUS:
1273 		synthesize_cpus((struct cpu_map_entries *) data->data, map);
1274 		break;
1275 	case PERF_CPU_MAP__MASK:
1276 		synthesize_mask((struct perf_record_record_cpu_map *)data->data, map, max);
1277 	default:
1278 		break;
1279 	}
1280 }
1281 
1282 static struct perf_record_cpu_map *cpu_map_event__new(struct perf_cpu_map *map)
1283 {
1284 	size_t size = sizeof(struct perf_record_cpu_map);
1285 	struct perf_record_cpu_map *event;
1286 	int max;
1287 	u16 type;
1288 
1289 	event = cpu_map_data__alloc(map, &size, &type, &max);
1290 	if (!event)
1291 		return NULL;
1292 
1293 	event->header.type = PERF_RECORD_CPU_MAP;
1294 	event->header.size = size;
1295 	event->data.type   = type;
1296 
1297 	cpu_map_data__synthesize(&event->data, map, type, max);
1298 	return event;
1299 }
1300 
1301 int perf_event__synthesize_cpu_map(struct perf_tool *tool,
1302 				   struct perf_cpu_map *map,
1303 				   perf_event__handler_t process,
1304 				   struct machine *machine)
1305 {
1306 	struct perf_record_cpu_map *event;
1307 	int err;
1308 
1309 	event = cpu_map_event__new(map);
1310 	if (!event)
1311 		return -ENOMEM;
1312 
1313 	err = process(tool, (union perf_event *) event, NULL, machine);
1314 
1315 	free(event);
1316 	return err;
1317 }
1318 
1319 int perf_event__synthesize_stat_config(struct perf_tool *tool,
1320 				       struct perf_stat_config *config,
1321 				       perf_event__handler_t process,
1322 				       struct machine *machine)
1323 {
1324 	struct perf_record_stat_config *event;
1325 	int size, i = 0, err;
1326 
1327 	size  = sizeof(*event);
1328 	size += (PERF_STAT_CONFIG_TERM__MAX * sizeof(event->data[0]));
1329 
1330 	event = zalloc(size);
1331 	if (!event)
1332 		return -ENOMEM;
1333 
1334 	event->header.type = PERF_RECORD_STAT_CONFIG;
1335 	event->header.size = size;
1336 	event->nr          = PERF_STAT_CONFIG_TERM__MAX;
1337 
1338 #define ADD(__term, __val)					\
1339 	event->data[i].tag = PERF_STAT_CONFIG_TERM__##__term;	\
1340 	event->data[i].val = __val;				\
1341 	i++;
1342 
1343 	ADD(AGGR_MODE,	config->aggr_mode)
1344 	ADD(INTERVAL,	config->interval)
1345 	ADD(SCALE,	config->scale)
1346 
1347 	WARN_ONCE(i != PERF_STAT_CONFIG_TERM__MAX,
1348 		  "stat config terms unbalanced\n");
1349 #undef ADD
1350 
1351 	err = process(tool, (union perf_event *) event, NULL, machine);
1352 
1353 	free(event);
1354 	return err;
1355 }
1356 
1357 int perf_event__synthesize_stat(struct perf_tool *tool,
1358 				struct perf_cpu cpu, u32 thread, u64 id,
1359 				struct perf_counts_values *count,
1360 				perf_event__handler_t process,
1361 				struct machine *machine)
1362 {
1363 	struct perf_record_stat event;
1364 
1365 	event.header.type = PERF_RECORD_STAT;
1366 	event.header.size = sizeof(event);
1367 	event.header.misc = 0;
1368 
1369 	event.id        = id;
1370 	event.cpu       = cpu.cpu;
1371 	event.thread    = thread;
1372 	event.val       = count->val;
1373 	event.ena       = count->ena;
1374 	event.run       = count->run;
1375 
1376 	return process(tool, (union perf_event *) &event, NULL, machine);
1377 }
1378 
1379 int perf_event__synthesize_stat_round(struct perf_tool *tool,
1380 				      u64 evtime, u64 type,
1381 				      perf_event__handler_t process,
1382 				      struct machine *machine)
1383 {
1384 	struct perf_record_stat_round event;
1385 
1386 	event.header.type = PERF_RECORD_STAT_ROUND;
1387 	event.header.size = sizeof(event);
1388 	event.header.misc = 0;
1389 
1390 	event.time = evtime;
1391 	event.type = type;
1392 
1393 	return process(tool, (union perf_event *) &event, NULL, machine);
1394 }
1395 
1396 size_t perf_event__sample_event_size(const struct perf_sample *sample, u64 type, u64 read_format)
1397 {
1398 	size_t sz, result = sizeof(struct perf_record_sample);
1399 
1400 	if (type & PERF_SAMPLE_IDENTIFIER)
1401 		result += sizeof(u64);
1402 
1403 	if (type & PERF_SAMPLE_IP)
1404 		result += sizeof(u64);
1405 
1406 	if (type & PERF_SAMPLE_TID)
1407 		result += sizeof(u64);
1408 
1409 	if (type & PERF_SAMPLE_TIME)
1410 		result += sizeof(u64);
1411 
1412 	if (type & PERF_SAMPLE_ADDR)
1413 		result += sizeof(u64);
1414 
1415 	if (type & PERF_SAMPLE_ID)
1416 		result += sizeof(u64);
1417 
1418 	if (type & PERF_SAMPLE_STREAM_ID)
1419 		result += sizeof(u64);
1420 
1421 	if (type & PERF_SAMPLE_CPU)
1422 		result += sizeof(u64);
1423 
1424 	if (type & PERF_SAMPLE_PERIOD)
1425 		result += sizeof(u64);
1426 
1427 	if (type & PERF_SAMPLE_READ) {
1428 		result += sizeof(u64);
1429 		if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED)
1430 			result += sizeof(u64);
1431 		if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING)
1432 			result += sizeof(u64);
1433 		/* PERF_FORMAT_ID is forced for PERF_SAMPLE_READ */
1434 		if (read_format & PERF_FORMAT_GROUP) {
1435 			sz = sample->read.group.nr *
1436 			     sizeof(struct sample_read_value);
1437 			result += sz;
1438 		} else {
1439 			result += sizeof(u64);
1440 		}
1441 	}
1442 
1443 	if (type & PERF_SAMPLE_CALLCHAIN) {
1444 		sz = (sample->callchain->nr + 1) * sizeof(u64);
1445 		result += sz;
1446 	}
1447 
1448 	if (type & PERF_SAMPLE_RAW) {
1449 		result += sizeof(u32);
1450 		result += sample->raw_size;
1451 	}
1452 
1453 	if (type & PERF_SAMPLE_BRANCH_STACK) {
1454 		sz = sample->branch_stack->nr * sizeof(struct branch_entry);
1455 		/* nr, hw_idx */
1456 		sz += 2 * sizeof(u64);
1457 		result += sz;
1458 	}
1459 
1460 	if (type & PERF_SAMPLE_REGS_USER) {
1461 		if (sample->user_regs.abi) {
1462 			result += sizeof(u64);
1463 			sz = hweight64(sample->user_regs.mask) * sizeof(u64);
1464 			result += sz;
1465 		} else {
1466 			result += sizeof(u64);
1467 		}
1468 	}
1469 
1470 	if (type & PERF_SAMPLE_STACK_USER) {
1471 		sz = sample->user_stack.size;
1472 		result += sizeof(u64);
1473 		if (sz) {
1474 			result += sz;
1475 			result += sizeof(u64);
1476 		}
1477 	}
1478 
1479 	if (type & PERF_SAMPLE_WEIGHT_TYPE)
1480 		result += sizeof(u64);
1481 
1482 	if (type & PERF_SAMPLE_DATA_SRC)
1483 		result += sizeof(u64);
1484 
1485 	if (type & PERF_SAMPLE_TRANSACTION)
1486 		result += sizeof(u64);
1487 
1488 	if (type & PERF_SAMPLE_REGS_INTR) {
1489 		if (sample->intr_regs.abi) {
1490 			result += sizeof(u64);
1491 			sz = hweight64(sample->intr_regs.mask) * sizeof(u64);
1492 			result += sz;
1493 		} else {
1494 			result += sizeof(u64);
1495 		}
1496 	}
1497 
1498 	if (type & PERF_SAMPLE_PHYS_ADDR)
1499 		result += sizeof(u64);
1500 
1501 	if (type & PERF_SAMPLE_CGROUP)
1502 		result += sizeof(u64);
1503 
1504 	if (type & PERF_SAMPLE_DATA_PAGE_SIZE)
1505 		result += sizeof(u64);
1506 
1507 	if (type & PERF_SAMPLE_CODE_PAGE_SIZE)
1508 		result += sizeof(u64);
1509 
1510 	if (type & PERF_SAMPLE_AUX) {
1511 		result += sizeof(u64);
1512 		result += sample->aux_sample.size;
1513 	}
1514 
1515 	return result;
1516 }
1517 
1518 void __weak arch_perf_synthesize_sample_weight(const struct perf_sample *data,
1519 					       __u64 *array, u64 type __maybe_unused)
1520 {
1521 	*array = data->weight;
1522 }
1523 
1524 int perf_event__synthesize_sample(union perf_event *event, u64 type, u64 read_format,
1525 				  const struct perf_sample *sample)
1526 {
1527 	__u64 *array;
1528 	size_t sz;
1529 	/*
1530 	 * used for cross-endian analysis. See git commit 65014ab3
1531 	 * for why this goofiness is needed.
1532 	 */
1533 	union u64_swap u;
1534 
1535 	array = event->sample.array;
1536 
1537 	if (type & PERF_SAMPLE_IDENTIFIER) {
1538 		*array = sample->id;
1539 		array++;
1540 	}
1541 
1542 	if (type & PERF_SAMPLE_IP) {
1543 		*array = sample->ip;
1544 		array++;
1545 	}
1546 
1547 	if (type & PERF_SAMPLE_TID) {
1548 		u.val32[0] = sample->pid;
1549 		u.val32[1] = sample->tid;
1550 		*array = u.val64;
1551 		array++;
1552 	}
1553 
1554 	if (type & PERF_SAMPLE_TIME) {
1555 		*array = sample->time;
1556 		array++;
1557 	}
1558 
1559 	if (type & PERF_SAMPLE_ADDR) {
1560 		*array = sample->addr;
1561 		array++;
1562 	}
1563 
1564 	if (type & PERF_SAMPLE_ID) {
1565 		*array = sample->id;
1566 		array++;
1567 	}
1568 
1569 	if (type & PERF_SAMPLE_STREAM_ID) {
1570 		*array = sample->stream_id;
1571 		array++;
1572 	}
1573 
1574 	if (type & PERF_SAMPLE_CPU) {
1575 		u.val32[0] = sample->cpu;
1576 		u.val32[1] = 0;
1577 		*array = u.val64;
1578 		array++;
1579 	}
1580 
1581 	if (type & PERF_SAMPLE_PERIOD) {
1582 		*array = sample->period;
1583 		array++;
1584 	}
1585 
1586 	if (type & PERF_SAMPLE_READ) {
1587 		if (read_format & PERF_FORMAT_GROUP)
1588 			*array = sample->read.group.nr;
1589 		else
1590 			*array = sample->read.one.value;
1591 		array++;
1592 
1593 		if (read_format & PERF_FORMAT_TOTAL_TIME_ENABLED) {
1594 			*array = sample->read.time_enabled;
1595 			array++;
1596 		}
1597 
1598 		if (read_format & PERF_FORMAT_TOTAL_TIME_RUNNING) {
1599 			*array = sample->read.time_running;
1600 			array++;
1601 		}
1602 
1603 		/* PERF_FORMAT_ID is forced for PERF_SAMPLE_READ */
1604 		if (read_format & PERF_FORMAT_GROUP) {
1605 			sz = sample->read.group.nr *
1606 			     sizeof(struct sample_read_value);
1607 			memcpy(array, sample->read.group.values, sz);
1608 			array = (void *)array + sz;
1609 		} else {
1610 			*array = sample->read.one.id;
1611 			array++;
1612 		}
1613 	}
1614 
1615 	if (type & PERF_SAMPLE_CALLCHAIN) {
1616 		sz = (sample->callchain->nr + 1) * sizeof(u64);
1617 		memcpy(array, sample->callchain, sz);
1618 		array = (void *)array + sz;
1619 	}
1620 
1621 	if (type & PERF_SAMPLE_RAW) {
1622 		u.val32[0] = sample->raw_size;
1623 		*array = u.val64;
1624 		array = (void *)array + sizeof(u32);
1625 
1626 		memcpy(array, sample->raw_data, sample->raw_size);
1627 		array = (void *)array + sample->raw_size;
1628 	}
1629 
1630 	if (type & PERF_SAMPLE_BRANCH_STACK) {
1631 		sz = sample->branch_stack->nr * sizeof(struct branch_entry);
1632 		/* nr, hw_idx */
1633 		sz += 2 * sizeof(u64);
1634 		memcpy(array, sample->branch_stack, sz);
1635 		array = (void *)array + sz;
1636 	}
1637 
1638 	if (type & PERF_SAMPLE_REGS_USER) {
1639 		if (sample->user_regs.abi) {
1640 			*array++ = sample->user_regs.abi;
1641 			sz = hweight64(sample->user_regs.mask) * sizeof(u64);
1642 			memcpy(array, sample->user_regs.regs, sz);
1643 			array = (void *)array + sz;
1644 		} else {
1645 			*array++ = 0;
1646 		}
1647 	}
1648 
1649 	if (type & PERF_SAMPLE_STACK_USER) {
1650 		sz = sample->user_stack.size;
1651 		*array++ = sz;
1652 		if (sz) {
1653 			memcpy(array, sample->user_stack.data, sz);
1654 			array = (void *)array + sz;
1655 			*array++ = sz;
1656 		}
1657 	}
1658 
1659 	if (type & PERF_SAMPLE_WEIGHT_TYPE) {
1660 		arch_perf_synthesize_sample_weight(sample, array, type);
1661 		array++;
1662 	}
1663 
1664 	if (type & PERF_SAMPLE_DATA_SRC) {
1665 		*array = sample->data_src;
1666 		array++;
1667 	}
1668 
1669 	if (type & PERF_SAMPLE_TRANSACTION) {
1670 		*array = sample->transaction;
1671 		array++;
1672 	}
1673 
1674 	if (type & PERF_SAMPLE_REGS_INTR) {
1675 		if (sample->intr_regs.abi) {
1676 			*array++ = sample->intr_regs.abi;
1677 			sz = hweight64(sample->intr_regs.mask) * sizeof(u64);
1678 			memcpy(array, sample->intr_regs.regs, sz);
1679 			array = (void *)array + sz;
1680 		} else {
1681 			*array++ = 0;
1682 		}
1683 	}
1684 
1685 	if (type & PERF_SAMPLE_PHYS_ADDR) {
1686 		*array = sample->phys_addr;
1687 		array++;
1688 	}
1689 
1690 	if (type & PERF_SAMPLE_CGROUP) {
1691 		*array = sample->cgroup;
1692 		array++;
1693 	}
1694 
1695 	if (type & PERF_SAMPLE_DATA_PAGE_SIZE) {
1696 		*array = sample->data_page_size;
1697 		array++;
1698 	}
1699 
1700 	if (type & PERF_SAMPLE_CODE_PAGE_SIZE) {
1701 		*array = sample->code_page_size;
1702 		array++;
1703 	}
1704 
1705 	if (type & PERF_SAMPLE_AUX) {
1706 		sz = sample->aux_sample.size;
1707 		*array++ = sz;
1708 		memcpy(array, sample->aux_sample.data, sz);
1709 		array = (void *)array + sz;
1710 	}
1711 
1712 	return 0;
1713 }
1714 
1715 int perf_event__synthesize_id_sample(__u64 *array, u64 type, const struct perf_sample *sample)
1716 {
1717 	__u64 *start = array;
1718 
1719 	/*
1720 	 * used for cross-endian analysis. See git commit 65014ab3
1721 	 * for why this goofiness is needed.
1722 	 */
1723 	union u64_swap u;
1724 
1725 	if (type & PERF_SAMPLE_TID) {
1726 		u.val32[0] = sample->pid;
1727 		u.val32[1] = sample->tid;
1728 		*array = u.val64;
1729 		array++;
1730 	}
1731 
1732 	if (type & PERF_SAMPLE_TIME) {
1733 		*array = sample->time;
1734 		array++;
1735 	}
1736 
1737 	if (type & PERF_SAMPLE_ID) {
1738 		*array = sample->id;
1739 		array++;
1740 	}
1741 
1742 	if (type & PERF_SAMPLE_STREAM_ID) {
1743 		*array = sample->stream_id;
1744 		array++;
1745 	}
1746 
1747 	if (type & PERF_SAMPLE_CPU) {
1748 		u.val32[0] = sample->cpu;
1749 		u.val32[1] = 0;
1750 		*array = u.val64;
1751 		array++;
1752 	}
1753 
1754 	if (type & PERF_SAMPLE_IDENTIFIER) {
1755 		*array = sample->id;
1756 		array++;
1757 	}
1758 
1759 	return (void *)array - (void *)start;
1760 }
1761 
1762 int __perf_event__synthesize_id_index(struct perf_tool *tool, perf_event__handler_t process,
1763 				      struct evlist *evlist, struct machine *machine, size_t from)
1764 {
1765 	union perf_event *ev;
1766 	struct evsel *evsel;
1767 	size_t nr = 0, i = 0, sz, max_nr, n, pos;
1768 	size_t e1_sz = sizeof(struct id_index_entry);
1769 	size_t e2_sz = sizeof(struct id_index_entry_2);
1770 	size_t etot_sz = e1_sz + e2_sz;
1771 	bool e2_needed = false;
1772 	int err;
1773 
1774 	max_nr = (UINT16_MAX - sizeof(struct perf_record_id_index)) / etot_sz;
1775 
1776 	pos = 0;
1777 	evlist__for_each_entry(evlist, evsel) {
1778 		if (pos++ < from)
1779 			continue;
1780 		nr += evsel->core.ids;
1781 	}
1782 
1783 	if (!nr)
1784 		return 0;
1785 
1786 	pr_debug2("Synthesizing id index\n");
1787 
1788 	n = nr > max_nr ? max_nr : nr;
1789 	sz = sizeof(struct perf_record_id_index) + n * etot_sz;
1790 	ev = zalloc(sz);
1791 	if (!ev)
1792 		return -ENOMEM;
1793 
1794 	sz = sizeof(struct perf_record_id_index) + n * e1_sz;
1795 
1796 	ev->id_index.header.type = PERF_RECORD_ID_INDEX;
1797 	ev->id_index.nr = n;
1798 
1799 	pos = 0;
1800 	evlist__for_each_entry(evlist, evsel) {
1801 		u32 j;
1802 
1803 		if (pos++ < from)
1804 			continue;
1805 		for (j = 0; j < evsel->core.ids; j++, i++) {
1806 			struct id_index_entry *e;
1807 			struct id_index_entry_2 *e2;
1808 			struct perf_sample_id *sid;
1809 
1810 			if (i >= n) {
1811 				ev->id_index.header.size = sz + (e2_needed ? n * e2_sz : 0);
1812 				err = process(tool, ev, NULL, machine);
1813 				if (err)
1814 					goto out_err;
1815 				nr -= n;
1816 				i = 0;
1817 				e2_needed = false;
1818 			}
1819 
1820 			e = &ev->id_index.entries[i];
1821 
1822 			e->id = evsel->core.id[j];
1823 
1824 			sid = evlist__id2sid(evlist, e->id);
1825 			if (!sid) {
1826 				free(ev);
1827 				return -ENOENT;
1828 			}
1829 
1830 			e->idx = sid->idx;
1831 			e->cpu = sid->cpu.cpu;
1832 			e->tid = sid->tid;
1833 
1834 			if (sid->machine_pid)
1835 				e2_needed = true;
1836 
1837 			e2 = (void *)ev + sz;
1838 			e2[i].machine_pid = sid->machine_pid;
1839 			e2[i].vcpu        = sid->vcpu.cpu;
1840 		}
1841 	}
1842 
1843 	sz = sizeof(struct perf_record_id_index) + nr * e1_sz;
1844 	ev->id_index.header.size = sz + (e2_needed ? nr * e2_sz : 0);
1845 	ev->id_index.nr = nr;
1846 
1847 	err = process(tool, ev, NULL, machine);
1848 out_err:
1849 	free(ev);
1850 
1851 	return err;
1852 }
1853 
1854 int perf_event__synthesize_id_index(struct perf_tool *tool, perf_event__handler_t process,
1855 				    struct evlist *evlist, struct machine *machine)
1856 {
1857 	return __perf_event__synthesize_id_index(tool, process, evlist, machine, 0);
1858 }
1859 
1860 int __machine__synthesize_threads(struct machine *machine, struct perf_tool *tool,
1861 				  struct target *target, struct perf_thread_map *threads,
1862 				  perf_event__handler_t process, bool needs_mmap,
1863 				  bool data_mmap, unsigned int nr_threads_synthesize)
1864 {
1865 	/*
1866 	 * When perf runs in non-root PID namespace, and the namespace's proc FS
1867 	 * is not mounted, nsinfo__is_in_root_namespace() returns false.
1868 	 * In this case, the proc FS is coming for the parent namespace, thus
1869 	 * perf tool will wrongly gather process info from its parent PID
1870 	 * namespace.
1871 	 *
1872 	 * To avoid the confusion that the perf tool runs in a child PID
1873 	 * namespace but it synthesizes thread info from its parent PID
1874 	 * namespace, returns failure with warning.
1875 	 */
1876 	if (!nsinfo__is_in_root_namespace()) {
1877 		pr_err("Perf runs in non-root PID namespace but it tries to ");
1878 		pr_err("gather process info from its parent PID namespace.\n");
1879 		pr_err("Please mount the proc file system properly, e.g. ");
1880 		pr_err("add the option '--mount-proc' for unshare command.\n");
1881 		return -EPERM;
1882 	}
1883 
1884 	if (target__has_task(target))
1885 		return perf_event__synthesize_thread_map(tool, threads, process, machine,
1886 							 needs_mmap, data_mmap);
1887 	else if (target__has_cpu(target))
1888 		return perf_event__synthesize_threads(tool, process, machine,
1889 						      needs_mmap, data_mmap,
1890 						      nr_threads_synthesize);
1891 	/* command specified */
1892 	return 0;
1893 }
1894 
1895 int machine__synthesize_threads(struct machine *machine, struct target *target,
1896 				struct perf_thread_map *threads, bool needs_mmap,
1897 				bool data_mmap, unsigned int nr_threads_synthesize)
1898 {
1899 	return __machine__synthesize_threads(machine, NULL, target, threads,
1900 					     perf_event__process, needs_mmap,
1901 					     data_mmap, nr_threads_synthesize);
1902 }
1903 
1904 static struct perf_record_event_update *event_update_event__new(size_t size, u64 type, u64 id)
1905 {
1906 	struct perf_record_event_update *ev;
1907 
1908 	size += sizeof(*ev);
1909 	size  = PERF_ALIGN(size, sizeof(u64));
1910 
1911 	ev = zalloc(size);
1912 	if (ev) {
1913 		ev->header.type = PERF_RECORD_EVENT_UPDATE;
1914 		ev->header.size = (u16)size;
1915 		ev->type	= type;
1916 		ev->id		= id;
1917 	}
1918 	return ev;
1919 }
1920 
1921 int perf_event__synthesize_event_update_unit(struct perf_tool *tool, struct evsel *evsel,
1922 					     perf_event__handler_t process)
1923 {
1924 	size_t size = strlen(evsel->unit);
1925 	struct perf_record_event_update *ev;
1926 	int err;
1927 
1928 	ev = event_update_event__new(size + 1, PERF_EVENT_UPDATE__UNIT, evsel->core.id[0]);
1929 	if (ev == NULL)
1930 		return -ENOMEM;
1931 
1932 	strlcpy(ev->data, evsel->unit, size + 1);
1933 	err = process(tool, (union perf_event *)ev, NULL, NULL);
1934 	free(ev);
1935 	return err;
1936 }
1937 
1938 int perf_event__synthesize_event_update_scale(struct perf_tool *tool, struct evsel *evsel,
1939 					      perf_event__handler_t process)
1940 {
1941 	struct perf_record_event_update *ev;
1942 	struct perf_record_event_update_scale *ev_data;
1943 	int err;
1944 
1945 	ev = event_update_event__new(sizeof(*ev_data), PERF_EVENT_UPDATE__SCALE, evsel->core.id[0]);
1946 	if (ev == NULL)
1947 		return -ENOMEM;
1948 
1949 	ev_data = (struct perf_record_event_update_scale *)ev->data;
1950 	ev_data->scale = evsel->scale;
1951 	err = process(tool, (union perf_event *)ev, NULL, NULL);
1952 	free(ev);
1953 	return err;
1954 }
1955 
1956 int perf_event__synthesize_event_update_name(struct perf_tool *tool, struct evsel *evsel,
1957 					     perf_event__handler_t process)
1958 {
1959 	struct perf_record_event_update *ev;
1960 	size_t len = strlen(evsel->name);
1961 	int err;
1962 
1963 	ev = event_update_event__new(len + 1, PERF_EVENT_UPDATE__NAME, evsel->core.id[0]);
1964 	if (ev == NULL)
1965 		return -ENOMEM;
1966 
1967 	strlcpy(ev->data, evsel->name, len + 1);
1968 	err = process(tool, (union perf_event *)ev, NULL, NULL);
1969 	free(ev);
1970 	return err;
1971 }
1972 
1973 int perf_event__synthesize_event_update_cpus(struct perf_tool *tool, struct evsel *evsel,
1974 					     perf_event__handler_t process)
1975 {
1976 	size_t size = sizeof(struct perf_record_event_update);
1977 	struct perf_record_event_update *ev;
1978 	int max, err;
1979 	u16 type;
1980 
1981 	if (!evsel->core.own_cpus)
1982 		return 0;
1983 
1984 	ev = cpu_map_data__alloc(evsel->core.own_cpus, &size, &type, &max);
1985 	if (!ev)
1986 		return -ENOMEM;
1987 
1988 	ev->header.type = PERF_RECORD_EVENT_UPDATE;
1989 	ev->header.size = (u16)size;
1990 	ev->type	= PERF_EVENT_UPDATE__CPUS;
1991 	ev->id		= evsel->core.id[0];
1992 
1993 	cpu_map_data__synthesize((struct perf_record_cpu_map_data *)ev->data,
1994 				 evsel->core.own_cpus, type, max);
1995 
1996 	err = process(tool, (union perf_event *)ev, NULL, NULL);
1997 	free(ev);
1998 	return err;
1999 }
2000 
2001 int perf_event__synthesize_attrs(struct perf_tool *tool, struct evlist *evlist,
2002 				 perf_event__handler_t process)
2003 {
2004 	struct evsel *evsel;
2005 	int err = 0;
2006 
2007 	evlist__for_each_entry(evlist, evsel) {
2008 		err = perf_event__synthesize_attr(tool, &evsel->core.attr, evsel->core.ids,
2009 						  evsel->core.id, process);
2010 		if (err) {
2011 			pr_debug("failed to create perf header attribute\n");
2012 			return err;
2013 		}
2014 	}
2015 
2016 	return err;
2017 }
2018 
2019 static bool has_unit(struct evsel *evsel)
2020 {
2021 	return evsel->unit && *evsel->unit;
2022 }
2023 
2024 static bool has_scale(struct evsel *evsel)
2025 {
2026 	return evsel->scale != 1;
2027 }
2028 
2029 int perf_event__synthesize_extra_attr(struct perf_tool *tool, struct evlist *evsel_list,
2030 				      perf_event__handler_t process, bool is_pipe)
2031 {
2032 	struct evsel *evsel;
2033 	int err;
2034 
2035 	/*
2036 	 * Synthesize other events stuff not carried within
2037 	 * attr event - unit, scale, name
2038 	 */
2039 	evlist__for_each_entry(evsel_list, evsel) {
2040 		if (!evsel->supported)
2041 			continue;
2042 
2043 		/*
2044 		 * Synthesize unit and scale only if it's defined.
2045 		 */
2046 		if (has_unit(evsel)) {
2047 			err = perf_event__synthesize_event_update_unit(tool, evsel, process);
2048 			if (err < 0) {
2049 				pr_err("Couldn't synthesize evsel unit.\n");
2050 				return err;
2051 			}
2052 		}
2053 
2054 		if (has_scale(evsel)) {
2055 			err = perf_event__synthesize_event_update_scale(tool, evsel, process);
2056 			if (err < 0) {
2057 				pr_err("Couldn't synthesize evsel evsel.\n");
2058 				return err;
2059 			}
2060 		}
2061 
2062 		if (evsel->core.own_cpus) {
2063 			err = perf_event__synthesize_event_update_cpus(tool, evsel, process);
2064 			if (err < 0) {
2065 				pr_err("Couldn't synthesize evsel cpus.\n");
2066 				return err;
2067 			}
2068 		}
2069 
2070 		/*
2071 		 * Name is needed only for pipe output,
2072 		 * perf.data carries event names.
2073 		 */
2074 		if (is_pipe) {
2075 			err = perf_event__synthesize_event_update_name(tool, evsel, process);
2076 			if (err < 0) {
2077 				pr_err("Couldn't synthesize evsel name.\n");
2078 				return err;
2079 			}
2080 		}
2081 	}
2082 	return 0;
2083 }
2084 
2085 int perf_event__synthesize_attr(struct perf_tool *tool, struct perf_event_attr *attr,
2086 				u32 ids, u64 *id, perf_event__handler_t process)
2087 {
2088 	union perf_event *ev;
2089 	size_t size;
2090 	int err;
2091 
2092 	size = sizeof(struct perf_event_attr);
2093 	size = PERF_ALIGN(size, sizeof(u64));
2094 	size += sizeof(struct perf_event_header);
2095 	size += ids * sizeof(u64);
2096 
2097 	ev = zalloc(size);
2098 
2099 	if (ev == NULL)
2100 		return -ENOMEM;
2101 
2102 	ev->attr.attr = *attr;
2103 	memcpy(ev->attr.id, id, ids * sizeof(u64));
2104 
2105 	ev->attr.header.type = PERF_RECORD_HEADER_ATTR;
2106 	ev->attr.header.size = (u16)size;
2107 
2108 	if (ev->attr.header.size == size)
2109 		err = process(tool, ev, NULL, NULL);
2110 	else
2111 		err = -E2BIG;
2112 
2113 	free(ev);
2114 
2115 	return err;
2116 }
2117 
2118 int perf_event__synthesize_tracing_data(struct perf_tool *tool, int fd, struct evlist *evlist,
2119 					perf_event__handler_t process)
2120 {
2121 	union perf_event ev;
2122 	struct tracing_data *tdata;
2123 	ssize_t size = 0, aligned_size = 0, padding;
2124 	struct feat_fd ff;
2125 
2126 	/*
2127 	 * We are going to store the size of the data followed
2128 	 * by the data contents. Since the fd descriptor is a pipe,
2129 	 * we cannot seek back to store the size of the data once
2130 	 * we know it. Instead we:
2131 	 *
2132 	 * - write the tracing data to the temp file
2133 	 * - get/write the data size to pipe
2134 	 * - write the tracing data from the temp file
2135 	 *   to the pipe
2136 	 */
2137 	tdata = tracing_data_get(&evlist->core.entries, fd, true);
2138 	if (!tdata)
2139 		return -1;
2140 
2141 	memset(&ev, 0, sizeof(ev));
2142 
2143 	ev.tracing_data.header.type = PERF_RECORD_HEADER_TRACING_DATA;
2144 	size = tdata->size;
2145 	aligned_size = PERF_ALIGN(size, sizeof(u64));
2146 	padding = aligned_size - size;
2147 	ev.tracing_data.header.size = sizeof(ev.tracing_data);
2148 	ev.tracing_data.size = aligned_size;
2149 
2150 	process(tool, &ev, NULL, NULL);
2151 
2152 	/*
2153 	 * The put function will copy all the tracing data
2154 	 * stored in temp file to the pipe.
2155 	 */
2156 	tracing_data_put(tdata);
2157 
2158 	ff = (struct feat_fd){ .fd = fd };
2159 	if (write_padded(&ff, NULL, 0, padding))
2160 		return -1;
2161 
2162 	return aligned_size;
2163 }
2164 
2165 int perf_event__synthesize_build_id(struct perf_tool *tool, struct dso *pos, u16 misc,
2166 				    perf_event__handler_t process, struct machine *machine)
2167 {
2168 	union perf_event ev;
2169 	size_t len;
2170 
2171 	if (!pos->hit)
2172 		return 0;
2173 
2174 	memset(&ev, 0, sizeof(ev));
2175 
2176 	len = pos->long_name_len + 1;
2177 	len = PERF_ALIGN(len, NAME_ALIGN);
2178 	memcpy(&ev.build_id.build_id, pos->bid.data, sizeof(pos->bid.data));
2179 	ev.build_id.header.type = PERF_RECORD_HEADER_BUILD_ID;
2180 	ev.build_id.header.misc = misc;
2181 	ev.build_id.pid = machine->pid;
2182 	ev.build_id.header.size = sizeof(ev.build_id) + len;
2183 	memcpy(&ev.build_id.filename, pos->long_name, pos->long_name_len);
2184 
2185 	return process(tool, &ev, NULL, machine);
2186 }
2187 
2188 int perf_event__synthesize_stat_events(struct perf_stat_config *config, struct perf_tool *tool,
2189 				       struct evlist *evlist, perf_event__handler_t process, bool attrs)
2190 {
2191 	int err;
2192 
2193 	if (attrs) {
2194 		err = perf_event__synthesize_attrs(tool, evlist, process);
2195 		if (err < 0) {
2196 			pr_err("Couldn't synthesize attrs.\n");
2197 			return err;
2198 		}
2199 	}
2200 
2201 	err = perf_event__synthesize_extra_attr(tool, evlist, process, attrs);
2202 	err = perf_event__synthesize_thread_map2(tool, evlist->core.threads, process, NULL);
2203 	if (err < 0) {
2204 		pr_err("Couldn't synthesize thread map.\n");
2205 		return err;
2206 	}
2207 
2208 	err = perf_event__synthesize_cpu_map(tool, evlist->core.user_requested_cpus, process, NULL);
2209 	if (err < 0) {
2210 		pr_err("Couldn't synthesize thread map.\n");
2211 		return err;
2212 	}
2213 
2214 	err = perf_event__synthesize_stat_config(tool, config, process, NULL);
2215 	if (err < 0) {
2216 		pr_err("Couldn't synthesize config.\n");
2217 		return err;
2218 	}
2219 
2220 	return 0;
2221 }
2222 
2223 extern const struct perf_header_feature_ops feat_ops[HEADER_LAST_FEATURE];
2224 
2225 int perf_event__synthesize_features(struct perf_tool *tool, struct perf_session *session,
2226 				    struct evlist *evlist, perf_event__handler_t process)
2227 {
2228 	struct perf_header *header = &session->header;
2229 	struct perf_record_header_feature *fe;
2230 	struct feat_fd ff;
2231 	size_t sz, sz_hdr;
2232 	int feat, ret;
2233 
2234 	sz_hdr = sizeof(fe->header);
2235 	sz = sizeof(union perf_event);
2236 	/* get a nice alignment */
2237 	sz = PERF_ALIGN(sz, page_size);
2238 
2239 	memset(&ff, 0, sizeof(ff));
2240 
2241 	ff.buf = malloc(sz);
2242 	if (!ff.buf)
2243 		return -ENOMEM;
2244 
2245 	ff.size = sz - sz_hdr;
2246 	ff.ph = &session->header;
2247 
2248 	for_each_set_bit(feat, header->adds_features, HEADER_FEAT_BITS) {
2249 		if (!feat_ops[feat].synthesize) {
2250 			pr_debug("No record header feature for header :%d\n", feat);
2251 			continue;
2252 		}
2253 
2254 		ff.offset = sizeof(*fe);
2255 
2256 		ret = feat_ops[feat].write(&ff, evlist);
2257 		if (ret || ff.offset <= (ssize_t)sizeof(*fe)) {
2258 			pr_debug("Error writing feature\n");
2259 			continue;
2260 		}
2261 		/* ff.buf may have changed due to realloc in do_write() */
2262 		fe = ff.buf;
2263 		memset(fe, 0, sizeof(*fe));
2264 
2265 		fe->feat_id = feat;
2266 		fe->header.type = PERF_RECORD_HEADER_FEATURE;
2267 		fe->header.size = ff.offset;
2268 
2269 		ret = process(tool, ff.buf, NULL, NULL);
2270 		if (ret) {
2271 			free(ff.buf);
2272 			return ret;
2273 		}
2274 	}
2275 
2276 	/* Send HEADER_LAST_FEATURE mark. */
2277 	fe = ff.buf;
2278 	fe->feat_id     = HEADER_LAST_FEATURE;
2279 	fe->header.type = PERF_RECORD_HEADER_FEATURE;
2280 	fe->header.size = sizeof(*fe);
2281 
2282 	ret = process(tool, ff.buf, NULL, NULL);
2283 
2284 	free(ff.buf);
2285 	return ret;
2286 }
2287 
2288 int perf_event__synthesize_for_pipe(struct perf_tool *tool,
2289 				    struct perf_session *session,
2290 				    struct perf_data *data,
2291 				    perf_event__handler_t process)
2292 {
2293 	int err;
2294 	int ret = 0;
2295 	struct evlist *evlist = session->evlist;
2296 
2297 	/*
2298 	 * We need to synthesize events first, because some
2299 	 * features works on top of them (on report side).
2300 	 */
2301 	err = perf_event__synthesize_attrs(tool, evlist, process);
2302 	if (err < 0) {
2303 		pr_err("Couldn't synthesize attrs.\n");
2304 		return err;
2305 	}
2306 	ret += err;
2307 
2308 	err = perf_event__synthesize_features(tool, session, evlist, process);
2309 	if (err < 0) {
2310 		pr_err("Couldn't synthesize features.\n");
2311 		return err;
2312 	}
2313 	ret += err;
2314 
2315 	if (have_tracepoints(&evlist->core.entries)) {
2316 		int fd = perf_data__fd(data);
2317 
2318 		/*
2319 		 * FIXME err <= 0 here actually means that
2320 		 * there were no tracepoints so its not really
2321 		 * an error, just that we don't need to
2322 		 * synthesize anything.  We really have to
2323 		 * return this more properly and also
2324 		 * propagate errors that now are calling die()
2325 		 */
2326 		err = perf_event__synthesize_tracing_data(tool,	fd, evlist,
2327 							  process);
2328 		if (err <= 0) {
2329 			pr_err("Couldn't record tracing data.\n");
2330 			return err;
2331 		}
2332 		ret += err;
2333 	}
2334 
2335 	return ret;
2336 }
2337 
2338 int parse_synth_opt(char *synth)
2339 {
2340 	char *p, *q;
2341 	int ret = 0;
2342 
2343 	if (synth == NULL)
2344 		return -1;
2345 
2346 	for (q = synth; (p = strsep(&q, ",")); p = q) {
2347 		if (!strcasecmp(p, "no") || !strcasecmp(p, "none"))
2348 			return 0;
2349 
2350 		if (!strcasecmp(p, "all"))
2351 			return PERF_SYNTH_ALL;
2352 
2353 		if (!strcasecmp(p, "task"))
2354 			ret |= PERF_SYNTH_TASK;
2355 		else if (!strcasecmp(p, "mmap"))
2356 			ret |= PERF_SYNTH_TASK | PERF_SYNTH_MMAP;
2357 		else if (!strcasecmp(p, "cgroup"))
2358 			ret |= PERF_SYNTH_CGROUP;
2359 		else
2360 			return -1;
2361 	}
2362 
2363 	return ret;
2364 }
2365