text: // SPDX-License-Identifier: GPL-2.0
  #include <dirent.h>
  #include <errno.h>
  #include <fcntl.h>
  #include <inttypes.h>
  #include <linux/kernel.h>
  #include <linux/types.h>
  #include <sys/types.h>
  #include <sys/stat.h>
  #include <unistd.h>
  #include <uapi/linux/mman.h> /* To get things like MAP_HUGETLB even on older libc headers */
  #include <api/fs/fs.h>
  #include <linux/perf_event.h>
  #include "event.h"
  #include "debug.h"
  #include "hist.h"
  #include "machine.h"
  #include "sort.h"
  #include "string2.h"
  #include "strlist.h"
  #include "thread.h"
  #include "thread_map.h"
  #include "sane_ctype.h"
  #include "map.h"
  #include "symbol.h"
  #include "symbol/kallsyms.h"
  #include "asm/bug.h"
  #include "stat.h"
  #include "session.h"
  #include "bpf-event.h"
  
  #define DEFAULT_PROC_MAP_PARSE_TIMEOUT 500
  
  static const char *perf_event__names[] = {
  	[0]					= "TOTAL",
  	[PERF_RECORD_MMAP]			= "MMAP",
  	[PERF_RECORD_MMAP2]			= "MMAP2",
  	[PERF_RECORD_LOST]			= "LOST",
  	[PERF_RECORD_COMM]			= "COMM",
  	[PERF_RECORD_EXIT]			= "EXIT",
  	[PERF_RECORD_THROTTLE]			= "THROTTLE",
  	[PERF_RECORD_UNTHROTTLE]		= "UNTHROTTLE",
  	[PERF_RECORD_FORK]			= "FORK",
  	[PERF_RECORD_READ]			= "READ",
  	[PERF_RECORD_SAMPLE]			= "SAMPLE",
  	[PERF_RECORD_AUX]			= "AUX",
  	[PERF_RECORD_ITRACE_START]		= "ITRACE_START",
  	[PERF_RECORD_LOST_SAMPLES]		= "LOST_SAMPLES",
  	[PERF_RECORD_SWITCH]			= "SWITCH",
  	[PERF_RECORD_SWITCH_CPU_WIDE]		= "SWITCH_CPU_WIDE",
  	[PERF_RECORD_NAMESPACES]		= "NAMESPACES",
  	[PERF_RECORD_KSYMBOL]			= "KSYMBOL",
  	[PERF_RECORD_BPF_EVENT]			= "BPF_EVENT",
  	[PERF_RECORD_HEADER_ATTR]		= "ATTR",
  	[PERF_RECORD_HEADER_EVENT_TYPE]		= "EVENT_TYPE",
  	[PERF_RECORD_HEADER_TRACING_DATA]	= "TRACING_DATA",
  	[PERF_RECORD_HEADER_BUILD_ID]		= "BUILD_ID",
  	[PERF_RECORD_FINISHED_ROUND]		= "FINISHED_ROUND",
  	[PERF_RECORD_ID_INDEX]			= "ID_INDEX",
  	[PERF_RECORD_AUXTRACE_INFO]		= "AUXTRACE_INFO",
  	[PERF_RECORD_AUXTRACE]			= "AUXTRACE",
  	[PERF_RECORD_AUXTRACE_ERROR]		= "AUXTRACE_ERROR",
  	[PERF_RECORD_THREAD_MAP]		= "THREAD_MAP",
  	[PERF_RECORD_CPU_MAP]			= "CPU_MAP",
  	[PERF_RECORD_STAT_CONFIG]		= "STAT_CONFIG",
  	[PERF_RECORD_STAT]			= "STAT",
  	[PERF_RECORD_STAT_ROUND]		= "STAT_ROUND",
  	[PERF_RECORD_EVENT_UPDATE]		= "EVENT_UPDATE",
  	[PERF_RECORD_TIME_CONV]			= "TIME_CONV",
  	[PERF_RECORD_HEADER_FEATURE]		= "FEATURE",
  	[PERF_RECORD_COMPRESSED]		= "COMPRESSED",
  };
  
  static const char *perf_ns__names[] = {
  	[NET_NS_INDEX]		= "net",
  	[UTS_NS_INDEX]		= "uts",
  	[IPC_NS_INDEX]		= "ipc",
  	[PID_NS_INDEX]		= "pid",
  	[USER_NS_INDEX]		= "user",
  	[MNT_NS_INDEX]		= "mnt",
  	[CGROUP_NS_INDEX]	= "cgroup",
  };
  
  unsigned int proc_map_timeout = DEFAULT_PROC_MAP_PARSE_TIMEOUT;
  
  const char *perf_event__name(unsigned int id)
  {
  	if (id >= ARRAY_SIZE(perf_event__names))
  		return "INVALID";
  	if (!perf_event__names[id])
  		return "UNKNOWN";
  	return perf_event__names[id];
  }
  
  static const char *perf_ns__name(unsigned int id)
  {
  	if (id >= ARRAY_SIZE(perf_ns__names))
  		return "UNKNOWN";
  	return perf_ns__names[id];
  }
  
  int perf_tool__process_synth_event(struct perf_tool *tool,
  				   union perf_event *event,
  				   struct machine *machine,
  				   perf_event__handler_t process)
  {
  	struct perf_sample synth_sample = {
  	.pid	   = -1,
  	.tid	   = -1,
  	.time	   = -1,
  	.stream_id = -1,
  	.cpu	   = -1,
  	.period	   = 1,
  	.cpumode   = event->header.misc & PERF_RECORD_MISC_CPUMODE_MASK,
  	};
  
  	return process(tool, event, &synth_sample, machine);
  };
  
  /*
   * Assumes that the first 4095 bytes of /proc/pid/stat contains
   * the comm, tgid and ppid.
   */
  static int perf_event__get_comm_ids(pid_t pid, char *comm, size_t len,
  				    pid_t *tgid, pid_t *ppid)
  {
  	char filename[PATH_MAX];
  	char bf[4096];
  	int fd;
  	size_t size = 0;
  	ssize_t n;
  	char *name, *tgids, *ppids;
  
  	*tgid = -1;
  	*ppid = -1;
  
  	snprintf(filename, sizeof(filename), "/proc/%d/status", pid);
  
  	fd = open(filename, O_RDONLY);
  	if (fd < 0) {
  		pr_debug("couldn't open %s\n", filename);
  		return -1;
  	}
  
  	n = read(fd, bf, sizeof(bf) - 1);
  	close(fd);
  	if (n <= 0) {
  		pr_warning("Couldn't get COMM, tigd and ppid for pid %d\n",
  			   pid);
  		return -1;
  	}
  	bf[n] = '\0';
  
  	name = strstr(bf, "Name:");
  	tgids = strstr(bf, "Tgid:");
  	ppids = strstr(bf, "PPid:");
  
  	if (name) {
  		char *nl;
  
  		name += 5;  /* strlen("Name:") */
  		name = ltrim(name);
  
  		nl = strchr(name, '\n');
  		if (nl)
  			*nl = '\0';
  
  		size = strlen(name);
  		if (size >= len)
  			size = len - 1;
  		memcpy(comm, name, size);
  		comm[size] = '\0';
  	} else {
  		pr_debug("Name: string not found for pid %d\n", pid);
  	}
  
  	if (tgids) {
  		tgids += 5;  /* strlen("Tgid:") */
  		*tgid = atoi(tgids);
  	} else {
  		pr_debug("Tgid: string not found for pid %d\n", pid);
  	}
  
  	if (ppids) {
  		ppids += 5;  /* strlen("PPid:") */
  		*ppid = atoi(ppids);
  	} else {
  		pr_debug("PPid: string not found for pid %d\n", pid);
  	}
  
  	return 0;
  }
  
  static int perf_event__prepare_comm(union perf_event *event, pid_t pid,
  				    struct machine *machine,
  				    pid_t *tgid, pid_t *ppid)
  {
  	size_t size;
  
  	*ppid = -1;
  
  	memset(&event->comm, 0, sizeof(event->comm));
  
  	if (machine__is_host(machine)) {
  		if (perf_event__get_comm_ids(pid, event->comm.comm,
  					     sizeof(event->comm.comm),
  					     tgid, ppid) != 0) {
  			return -1;
  		}
  	} else {
  		*tgid = machine->pid;
  	}
  
  	if (*tgid < 0)
  		return -1;
  
  	event->comm.pid = *tgid;
  	event->comm.header.type = PERF_RECORD_COMM;
  
  	size = strlen(event->comm.comm) + 1;
  	size = PERF_ALIGN(size, sizeof(u64));
  	memset(event->comm.comm + size, 0, machine->id_hdr_size);
  	event->comm.header.size = (sizeof(event->comm) -
  				(sizeof(event->comm.comm) - size) +
  				machine->id_hdr_size);
  	event->comm.tid = pid;
  
  	return 0;
  }
  
  pid_t perf_event__synthesize_comm(struct perf_tool *tool,
  					 union perf_event *event, pid_t pid,
  					 perf_event__handler_t process,
  					 struct machine *machine)
  {
  	pid_t tgid, ppid;
  
  	if (perf_event__prepare_comm(event, pid, machine, &tgid, &ppid) != 0)
  		return -1;
  
  	if (perf_tool__process_synth_event(tool, event, machine, process) != 0)
  		return -1;
  
  	return tgid;
  }
  
  static void perf_event__get_ns_link_info(pid_t pid, const char *ns,
  					 struct perf_ns_link_info *ns_link_info)
  {
  	struct stat64 st;
  	char proc_ns[128];
  
  	sprintf(proc_ns, "/proc/%u/ns/%s", pid, ns);
  	if (stat64(proc_ns, &st) == 0) {
  		ns_link_info->dev = st.st_dev;
  		ns_link_info->ino = st.st_ino;
  	}
  }
  
  int perf_event__synthesize_namespaces(struct perf_tool *tool,
  				      union perf_event *event,
  				      pid_t pid, pid_t tgid,
  				      perf_event__handler_t process,
  				      struct machine *machine)
  {
  	u32 idx;
  	struct perf_ns_link_info *ns_link_info;
  
  	if (!tool || !tool->namespace_events)
  		return 0;
  
  	memset(&event->namespaces, 0, (sizeof(event->namespaces) +
  	       (NR_NAMESPACES * sizeof(struct perf_ns_link_info)) +
  	       machine->id_hdr_size));
  
  	event->namespaces.pid = tgid;
  	event->namespaces.tid = pid;
  
  	event->namespaces.nr_namespaces = NR_NAMESPACES;
  
  	ns_link_info = event->namespaces.link_info;
  
  	for (idx = 0; idx < event->namespaces.nr_namespaces; idx++)
  		perf_event__get_ns_link_info(pid, perf_ns__name(idx),
  					     &ns_link_info[idx]);
  
  	event->namespaces.header.type = PERF_RECORD_NAMESPACES;
  
  	event->namespaces.header.size = (sizeof(event->namespaces) +
  			(NR_NAMESPACES * sizeof(struct perf_ns_link_info)) +
  			machine->id_hdr_size);
  
  	if (perf_tool__process_synth_event(tool, event, machine, process) != 0)
  		return -1;
  
  	return 0;
  }
  
  static int perf_event__synthesize_fork(struct perf_tool *tool,
  				       union perf_event *event,
  				       pid_t pid, pid_t tgid, pid_t ppid,
  				       perf_event__handler_t process,
  				       struct machine *machine)
  {
  	memset(&event->fork, 0, sizeof(event->fork) + machine->id_hdr_size);
  
  	/*
  	 * for main thread set parent to ppid from status file. For other
  	 * threads set parent pid to main thread. ie., assume main thread
  	 * spawns all threads in a process
  	*/
  	if (tgid == pid) {
  		event->fork.ppid = ppid;
  		event->fork.ptid = ppid;
  	} else {
  		event->fork.ppid = tgid;
  		event->fork.ptid = tgid;
  	}
  	event->fork.pid  = tgid;
  	event->fork.tid  = pid;
  	event->fork.header.type = PERF_RECORD_FORK;
  	event->fork.header.misc = PERF_RECORD_MISC_FORK_EXEC;
  
  	event->fork.header.size = (sizeof(event->fork) + machine->id_hdr_size);
  
  	if (perf_tool__process_synth_event(tool, event, machine, process) != 0)
  		return -1;
  
  	return 0;
  }
  
  int perf_event__synthesize_mmap_events(struct perf_tool *tool,
  				       union perf_event *event,
  				       pid_t pid, pid_t tgid,
  				       perf_event__handler_t process,
  				       struct machine *machine,
  				       bool mmap_data)
  {
  	char filename[PATH_MAX];
  	FILE *fp;
  	unsigned long long t;
  	bool truncation = false;
  	unsigned long long timeout = proc_map_timeout * 1000000ULL;
  	int rc = 0;
  	const char *hugetlbfs_mnt = hugetlbfs__mountpoint();
  	int hugetlbfs_mnt_len = hugetlbfs_mnt ? strlen(hugetlbfs_mnt) : 0;
  
  	if (machine__is_default_guest(machine))
  		return 0;
  
  	snprintf(filename, sizeof(filename), "%s/proc/%d/task/%d/maps",
  		 machine->root_dir, pid, pid);
  
  	fp = fopen(filename, "r");
  	if (fp == NULL) {
  		/*
  		 * We raced with a task exiting - just return:
  		 */
  		pr_debug("couldn't open %s\n", filename);
  		return -1;
  	}
  
  	event->header.type = PERF_RECORD_MMAP2;
  	t = rdclock();
  
  	while (1) {
  		char bf[BUFSIZ];
  		char prot[5];
  		char execname[PATH_MAX];
  		char anonstr[] = "//anon";
  		unsigned int ino;
  		size_t size;
  		ssize_t n;
  
  		if (fgets(bf, sizeof(bf), fp) == NULL)
  			break;
  
  		if ((rdclock() - t) > timeout) {
  			pr_warning("Reading %s time out. "
  				   "You may want to increase "
  				   "the time limit by --proc-map-timeout\n",
  				   filename);
  			truncation = true;
  			goto out;
  		}
  
  		/* ensure null termination since stack will be reused. */
  		strcpy(execname, "");
  
  		/* 00400000-0040c000 r-xp 00000000 fd:01 41038  /bin/cat */
  		n = sscanf(bf, "%"PRIx64"-%"PRIx64" %s %"PRIx64" %x:%x %u %[^\n]\n",
  		       &event->mmap2.start, &event->mmap2.len, prot,
  		       &event->mmap2.pgoff, &event->mmap2.maj,
  		       &event->mmap2.min,
  		       &ino, execname);
  
  		/*
   		 * Anon maps don't have the execname.
   		 */
  		if (n < 7)
  			continue;
  
  		event->mmap2.ino = (u64)ino;
  
  		/*
  		 * Just like the kernel, see __perf_event_mmap in kernel/perf_event.c
  		 */
  		if (machine__is_host(machine))
  			event->header.misc = PERF_RECORD_MISC_USER;
  		else
  			event->header.misc = PERF_RECORD_MISC_GUEST_USER;
  
  		/* map protection and flags bits */
  		event->mmap2.prot = 0;
  		event->mmap2.flags = 0;
  		if (prot[0] == 'r')
  			event->mmap2.prot |= PROT_READ;
  		if (prot[1] == 'w')
  			event->mmap2.prot |= PROT_WRITE;
  		if (prot[2] == 'x')
  			event->mmap2.prot |= PROT_EXEC;
  
  		if (prot[3] == 's')
  			event->mmap2.flags |= MAP_SHARED;
  		else
  			event->mmap2.flags |= MAP_PRIVATE;
  
  		if (prot[2] != 'x') {
  			if (!mmap_data || prot[0] != 'r')
  				continue;
  
  			event->header.misc |= PERF_RECORD_MISC_MMAP_DATA;
  		}
  
  out:
  		if (truncation)
  			event->header.misc |= PERF_RECORD_MISC_PROC_MAP_PARSE_TIMEOUT;
  
  		if (!strcmp(execname, ""))
  			strcpy(execname, anonstr);
  
  		if (hugetlbfs_mnt_len &&
  		    !strncmp(execname, hugetlbfs_mnt, hugetlbfs_mnt_len)) {
  			strcpy(execname, anonstr);
  			event->mmap2.flags |= MAP_HUGETLB;
  		}
  
  		size = strlen(execname) + 1;
  		memcpy(event->mmap2.filename, execname, size);
  		size = PERF_ALIGN(size, sizeof(u64));
  		event->mmap2.len -= event->mmap.start;
  		event->mmap2.header.size = (sizeof(event->mmap2) -
  					(sizeof(event->mmap2.filename) - size));
  		memset(event->mmap2.filename + size, 0, machine->id_hdr_size);
  		event->mmap2.header.size += machine->id_hdr_size;
  		event->mmap2.pid = tgid;
  		event->mmap2.tid = pid;
  
  		if (perf_tool__process_synth_event(tool, event, machine, process) != 0) {
  			rc = -1;
  			break;
  		}
  
  		if (truncation)
  			break;
  	}
  
  	fclose(fp);
  	return rc;
  }
  
  int perf_event__synthesize_modules(struct perf_tool *tool,
  				   perf_event__handler_t process,
  				   struct machine *machine)
  {
  	int rc = 0;
  	struct map *pos;
  	struct maps *maps = machine__kernel_maps(machine);
  	union perf_event *event = zalloc((sizeof(event->mmap) +
  					  machine->id_hdr_size));
  	if (event == NULL) {
  		pr_debug("Not enough memory synthesizing mmap event "
  			 "for kernel modules\n");
  		return -1;
  	}
  
  	event->header.type = PERF_RECORD_MMAP;
  
  	/*
  	 * kernel uses 0 for user space maps, see kernel/perf_event.c
  	 * __perf_event_mmap
  	 */
  	if (machine__is_host(machine))
  		event->header.misc = PERF_RECORD_MISC_KERNEL;
  	else
  		event->header.misc = PERF_RECORD_MISC_GUEST_KERNEL;
  
  	for (pos = maps__first(maps); pos; pos = map__next(pos)) {
  		size_t size;
  
  		if (!__map__is_kmodule(pos))
  			continue;
  
  		size = PERF_ALIGN(pos->dso->long_name_len + 1, sizeof(u64));
  		event->mmap.header.type = PERF_RECORD_MMAP;
  		event->mmap.header.size = (sizeof(event->mmap) -
  				        (sizeof(event->mmap.filename) - size));
  		memset(event->mmap.filename + size, 0, machine->id_hdr_size);
  		event->mmap.header.size += machine->id_hdr_size;
  		event->mmap.start = pos->start;
  		event->mmap.len   = pos->end - pos->start;
  		event->mmap.pid   = machine->pid;
  
  		memcpy(event->mmap.filename, pos->dso->long_name,
  		       pos->dso->long_name_len + 1);
  		if (perf_tool__process_synth_event(tool, event, machine, process) != 0) {
  			rc = -1;
  			break;
  		}
  	}
  
  	free(event);
  	return rc;
  }
  
  static int __event__synthesize_thread(union perf_event *comm_event,
  				      union perf_event *mmap_event,
  				      union perf_event *fork_event,
  				      union perf_event *namespaces_event,
  				      pid_t pid, int full,
  				      perf_event__handler_t process,
  				      struct perf_tool *tool,
  				      struct machine *machine,
  				      bool mmap_data)
  {
  	char filename[PATH_MAX];
  	DIR *tasks;
  	struct dirent *dirent;
  	pid_t tgid, ppid;
  	int rc = 0;
  
  	/* special case: only send one comm event using passed in pid */
  	if (!full) {
  		tgid = perf_event__synthesize_comm(tool, comm_event, pid,
  						   process, machine);
  
  		if (tgid == -1)
  			return -1;
  
  		if (perf_event__synthesize_namespaces(tool, namespaces_event, pid,
  						      tgid, process, machine) < 0)
  			return -1;
  
  		/*
  		 * send mmap only for thread group leader
  		 * see thread__init_map_groups
  		 */
  		if (pid == tgid &&
  		    perf_event__synthesize_mmap_events(tool, mmap_event, pid, tgid,
  						       process, machine, mmap_data))
  			return -1;
  
  		return 0;
  	}
  
  	if (machine__is_default_guest(machine))
  		return 0;
  
  	snprintf(filename, sizeof(filename), "%s/proc/%d/task",
  		 machine->root_dir, pid);
  
  	tasks = opendir(filename);
  	if (tasks == NULL) {
  		pr_debug("couldn't open %s\n", filename);
  		return 0;
  	}
  
  	while ((dirent = readdir(tasks)) != NULL) {
  		char *end;
  		pid_t _pid;
  
  		_pid = strtol(dirent->d_name, &end, 10);
  		if (*end)
  			continue;
  
  		rc = -1;
  		if (perf_event__prepare_comm(comm_event, _pid, machine,
  					     &tgid, &ppid) != 0)
  			break;
  
  		if (perf_event__synthesize_fork(tool, fork_event, _pid, tgid,
  						ppid, process, machine) < 0)
  			break;
  
  		if (perf_event__synthesize_namespaces(tool, namespaces_event, _pid,
  						      tgid, process, machine) < 0)
  			break;
  
  		/*
  		 * Send the prepared comm event
  		 */
  		if (perf_tool__process_synth_event(tool, comm_event, machine, process) != 0)
  			break;
  
  		rc = 0;
  		if (_pid == pid) {
  			/* process the parent's maps too */
  			rc = perf_event__synthesize_mmap_events(tool, mmap_event, pid, tgid,
  						process, machine, mmap_data);
  			if (rc)
  				break;
  		}
  	}
  
  	closedir(tasks);
  	return rc;
  }
  
  int perf_event__synthesize_thread_map(struct perf_tool *tool,
  				      struct thread_map *threads,
  				      perf_event__handler_t process,
  				      struct machine *machine,
  				      bool mmap_data)
  {
  	union perf_event *comm_event, *mmap_event, *fork_event;
  	union perf_event *namespaces_event;
  	int err = -1, thread, j;
  
  	comm_event = malloc(sizeof(comm_event->comm) + machine->id_hdr_size);
  	if (comm_event == NULL)
  		goto out;
  
  	mmap_event = malloc(sizeof(mmap_event->mmap2) + machine->id_hdr_size);
  	if (mmap_event == NULL)
  		goto out_free_comm;
  
  	fork_event = malloc(sizeof(fork_event->fork) + machine->id_hdr_size);
  	if (fork_event == NULL)
  		goto out_free_mmap;
  
  	namespaces_event = malloc(sizeof(namespaces_event->namespaces) +
  				  (NR_NAMESPACES * sizeof(struct perf_ns_link_info)) +
  				  machine->id_hdr_size);
  	if (namespaces_event == NULL)
  		goto out_free_fork;
  
  	err = 0;
  	for (thread = 0; thread < threads->nr; ++thread) {
  		if (__event__synthesize_thread(comm_event, mmap_event,
  					       fork_event, namespaces_event,
  					       thread_map__pid(threads, thread), 0,
  					       process, tool, machine,
  					       mmap_data)) {
  			err = -1;
  			break;
  		}
  
  		/*
  		 * comm.pid is set to thread group id by
  		 * perf_event__synthesize_comm
  		 */
  		if ((int) comm_event->comm.pid != thread_map__pid(threads, thread)) {
  			bool need_leader = true;
  
  			/* is thread group leader in thread_map? */
  			for (j = 0; j < threads->nr; ++j) {
  				if ((int) comm_event->comm.pid == thread_map__pid(threads, j)) {
  					need_leader = false;
  					break;
  				}
  			}
  
  			/* if not, generate events for it */
  			if (need_leader &&
  			    __event__synthesize_thread(comm_event, mmap_event,
  						       fork_event, namespaces_event,
  						       comm_event->comm.pid, 0,
  						       process, tool, machine,
  						       mmap_data)) {
  				err = -1;
  				break;
  			}
  		}
  	}
  	free(namespaces_event);
  out_free_fork:
  	free(fork_event);
  out_free_mmap:
  	free(mmap_event);
  out_free_comm:
  	free(comm_event);
  out:
  	return err;
  }
  
  static int __perf_event__synthesize_threads(struct perf_tool *tool,
  					    perf_event__handler_t process,
  					    struct machine *machine,
  					    bool mmap_data,
  					    struct dirent **dirent,
  					    int start,
  					    int num)
  {
  	union perf_event *comm_event, *mmap_event, *fork_event;
  	union perf_event *namespaces_event;
  	int err = -1;
  	char *end;
  	pid_t pid;
  	int i;
  
  	comm_event = malloc(sizeof(comm_event->comm) + machine->id_hdr_size);
  	if (comm_event == NULL)
  		goto out;
  
  	mmap_event = malloc(sizeof(mmap_event->mmap2) + machine->id_hdr_size);
  	if (mmap_event == NULL)
  		goto out_free_comm;
  
  	fork_event = malloc(sizeof(fork_event->fork) + machine->id_hdr_size);
  	if (fork_event == NULL)
  		goto out_free_mmap;
  
  	namespaces_event = malloc(sizeof(namespaces_event->namespaces) +
  				  (NR_NAMESPACES * sizeof(struct perf_ns_link_info)) +
  				  machine->id_hdr_size);
  	if (namespaces_event == NULL)
  		goto out_free_fork;
  
  	for (i = start; i < start + num; i++) {
  		if (!isdigit(dirent[i]->d_name[0]))
  			continue;
  
  		pid = (pid_t)strtol(dirent[i]->d_name, &end, 10);
  		/* only interested in proper numerical dirents */
  		if (*end)
  			continue;
  		/*
  		 * We may race with exiting thread, so don't stop just because
  		 * one thread couldn't be synthesized.
  		 */
  		__event__synthesize_thread(comm_event, mmap_event, fork_event,
  					   namespaces_event, pid, 1, process,
  					   tool, machine, mmap_data);
  	}
  	err = 0;
  
  	free(namespaces_event);
  out_free_fork:
  	free(fork_event);
  out_free_mmap:
  	free(mmap_event);
  out_free_comm:
  	free(comm_event);
  out:
  	return err;
  }
  
  struct synthesize_threads_arg {
  	struct perf_tool *tool;
  	perf_event__handler_t process;
  	struct machine *machine;
  	bool mmap_data;
  	struct dirent **dirent;
  	int num;
  	int start;
  };
  
  static void *synthesize_threads_worker(void *arg)
  {
  	struct synthesize_threads_arg *args = arg;
  
  	__perf_event__synthesize_threads(args->tool, args->process,
  					 args->machine, args->mmap_data,
  					 args->dirent,
  					 args->start, args->num);
  	return NULL;
  }
  
  int perf_event__synthesize_threads(struct perf_tool *tool,
  				   perf_event__handler_t process,
  				   struct machine *machine,
  				   bool mmap_data,
  				   unsigned int nr_threads_synthesize)
  {
  	struct synthesize_threads_arg *args = NULL;
  	pthread_t *synthesize_threads = NULL;
  	char proc_path[PATH_MAX];
  	struct dirent **dirent;
  	int num_per_thread;
  	int m, n, i, j;
  	int thread_nr;
  	int base = 0;
  	int err = -1;
  
  
  	if (machine__is_default_guest(machine))
  		return 0;
  
  	snprintf(proc_path, sizeof(proc_path), "%s/proc", machine->root_dir);
  	n = scandir(proc_path, &dirent, 0, alphasort);
  	if (n < 0)
  		return err;
  
  	if (nr_threads_synthesize == UINT_MAX)
  		thread_nr = sysconf(_SC_NPROCESSORS_ONLN);
  	else
  		thread_nr = nr_threads_synthesize;
  
  	if (thread_nr <= 1) {
  		err = __perf_event__synthesize_threads(tool, process,
  						       machine, mmap_data,
  						       dirent, base, n);
  		goto free_dirent;
  	}
  	if (thread_nr > n)
  		thread_nr = n;
  
  	synthesize_threads = calloc(sizeof(pthread_t), thread_nr);
  	if (synthesize_threads == NULL)
  		goto free_dirent;
  
  	args = calloc(sizeof(*args), thread_nr);
  	if (args == NULL)
  		goto free_threads;
  
  	num_per_thread = n / thread_nr;
  	m = n % thread_nr;
  	for (i = 0; i < thread_nr; i++) {
  		args[i].tool = tool;
  		args[i].process = process;
  		args[i].machine = machine;
  		args[i].mmap_data = mmap_data;
  		args[i].dirent = dirent;
  	}
  	for (i = 0; i < m; i++) {
  		args[i].num = num_per_thread + 1;
  		args[i].start = i * args[i].num;
  	}
  	if (i != 0)
  		base = args[i-1].start + args[i-1].num;
  	for (j = i; j < thread_nr; j++) {
  		args[j].num = num_per_thread;
  		args[j].start = base + (j - i) * args[i].num;
  	}
  
  	for (i = 0; i < thread_nr; i++) {
  		if (pthread_create(&synthesize_threads[i], NULL,
  				   synthesize_threads_worker, &args[i]))
  			goto out_join;
  	}
  	err = 0;
  out_join:
  	for (i = 0; i < thread_nr; i++)
  		pthread_join(synthesize_threads[i], NULL);
  	free(args);
  free_threads:
  	free(synthesize_threads);
  free_dirent:
  	for (i = 0; i < n; i++)
  		free(dirent[i]);
  	free(dirent);
  
  	return err;
  }
  
  struct process_symbol_args {
  	const char *name;
  	u64	   start;
  };
  
  static int find_symbol_cb(void *arg, const char *name, char type,
  			  u64 start)
  {
  	struct process_symbol_args *args = arg;
  
  	/*
  	 * Must be a function or at least an alias, as in PARISC64, where "_text" is
  	 * an 'A' to the same address as "_stext".
  	 */
  	if (!(kallsyms__is_function(type) ||
  	      type == 'A') || strcmp(name, args->name))
  		return 0;
  
  	args->start = start;
  	return 1;
  }
  
  int kallsyms__get_function_start(const char *kallsyms_filename,
  				 const char *symbol_name, u64 *addr)
  {
  	struct process_symbol_args args = { .name = symbol_name, };
  
  	if (kallsyms__parse(kallsyms_filename, &args, find_symbol_cb) <= 0)
  		return -1;
  
  	*addr = args.start;
  	return 0;
  }
  
  int __weak perf_event__synthesize_extra_kmaps(struct perf_tool *tool __maybe_unused,
  					      perf_event__handler_t process __maybe_unused,
  					      struct machine *machine __maybe_unused)
  {
  	return 0;
  }
  
  static int __perf_event__synthesize_kernel_mmap(struct perf_tool *tool,
  						perf_event__handler_t process,
  						struct machine *machine)
  {
  	size_t size;
  	struct map *map = machine__kernel_map(machine);
  	struct kmap *kmap;
  	int err;
  	union perf_event *event;
  
  	if (symbol_conf.kptr_restrict)
  		return -1;
  	if (map == NULL)
  		return -1;
  
  	/*
  	 * We should get this from /sys/kernel/sections/.text, but till that is
  	 * available use this, and after it is use this as a fallback for older
  	 * kernels.
  	 */
  	event = zalloc((sizeof(event->mmap) + machine->id_hdr_size));
  	if (event == NULL) {
  		pr_debug("Not enough memory synthesizing mmap event "
  			 "for kernel modules\n");
  		return -1;
  	}
  
  	if (machine__is_host(machine)) {
  		/*
  		 * kernel uses PERF_RECORD_MISC_USER for user space maps,
  		 * see kernel/perf_event.c __perf_event_mmap
  		 */
  		event->header.misc = PERF_RECORD_MISC_KERNEL;
  	} else {
  		event->header.misc = PERF_RECORD_MISC_GUEST_KERNEL;
  	}
  
  	kmap = map__kmap(map);
  	size = snprintf(event->mmap.filename, sizeof(event->mmap.filename),
  			"%s%s", machine->mmap_name, kmap->ref_reloc_sym->name) + 1;
  	size = PERF_ALIGN(size, sizeof(u64));
  	event->mmap.header.type = PERF_RECORD_MMAP;
  	event->mmap.header.size = (sizeof(event->mmap) -
  			(sizeof(event->mmap.filename) - size) + machine->id_hdr_size);
  	event->mmap.pgoff = kmap->ref_reloc_sym->addr;
  	event->mmap.start = map->start;
  	event->mmap.len   = map->end - event->mmap.start;
  	event->mmap.pid   = machine->pid;
  
  	err = perf_tool__process_synth_event(tool, event, machine, process);
  	free(event);
  
  	return err;
  }
  
  int perf_event__synthesize_kernel_mmap(struct perf_tool *tool,
  				       perf_event__handler_t process,
  				       struct machine *machine)
  {
  	int err;
  
  	err = __perf_event__synthesize_kernel_mmap(tool, process, machine);
  	if (err < 0)
  		return err;
  
  	return perf_event__synthesize_extra_kmaps(tool, process, machine);
  }
  
  int perf_event__synthesize_thread_map2(struct perf_tool *tool,
  				      struct thread_map *threads,
  				      perf_event__handler_t process,
  				      struct machine *machine)
  {
  	union perf_event *event;
  	int i, err, size;
  
  	size  = sizeof(event->thread_map);
  	size +=	threads->nr * sizeof(event->thread_map.entries[0]);
  
  	event = zalloc(size);
  	if (!event)
  		return -ENOMEM;
  
  	event->header.type = PERF_RECORD_THREAD_MAP;
  	event->header.size = size;
  	event->thread_map.nr = threads->nr;
  
  	for (i = 0; i < threads->nr; i++) {
  		struct thread_map_event_entry *entry = &event->thread_map.entries[i];
  		char *comm = thread_map__comm(threads, i);
  
  		if (!comm)
  			comm = (char *) "";
  
  		entry->pid = thread_map__pid(threads, i);
  		strncpy((char *) &entry->comm, comm, sizeof(entry->comm));
  	}
  
  	err = process(tool, event, NULL, machine);
  
  	free(event);
  	return err;
  }
  
  static void synthesize_cpus(struct cpu_map_entries *cpus,
  			    struct cpu_map *map)
  {
  	int i;
  
  	cpus->nr = map->nr;
  
  	for (i = 0; i < map->nr; i++)
  		cpus->cpu[i] = map->map[i];
  }
  
  static void synthesize_mask(struct cpu_map_mask *mask,
  			    struct cpu_map *map, int max)
  {
  	int i;
  
  	mask->nr = BITS_TO_LONGS(max);
  	mask->long_size = sizeof(long);
  
  	for (i = 0; i < map->nr; i++)
  		set_bit(map->map[i], mask->mask);
  }
  
  static size_t cpus_size(struct cpu_map *map)
  {
  	return sizeof(struct cpu_map_entries) + map->nr * sizeof(u16);
  }
  
  static size_t mask_size(struct cpu_map *map, int *max)
  {
  	int i;
  
  	*max = 0;
  
  	for (i = 0; i < map->nr; i++) {
  		/* bit possition of the cpu is + 1 */
  		int bit = map->map[i] + 1;
  
  		if (bit > *max)
  			*max = bit;
  	}
  
  	return sizeof(struct cpu_map_mask) + BITS_TO_LONGS(*max) * sizeof(long);
  }
  
  void *cpu_map_data__alloc(struct cpu_map *map, size_t *size, u16 *type, int *max)
  {
  	size_t size_cpus, size_mask;
  	bool is_dummy = cpu_map__empty(map);
  
  	/*
  	 * Both array and mask data have variable size based
  	 * on the number of cpus and their actual values.
  	 * The size of the 'struct cpu_map_data' is:
  	 *
  	 *   array = size of 'struct cpu_map_entries' +
  	 *           number of cpus * sizeof(u64)
  	 *
  	 *   mask  = size of 'struct cpu_map_mask' +
  	 *           maximum cpu bit converted to size of longs
  	 *
  	 * and finaly + the size of 'struct cpu_map_data'.
  	 */
  	size_cpus = cpus_size(map);
  	size_mask = mask_size(map, max);
  
  	if (is_dummy || (size_cpus < size_mask)) {
  		*size += size_cpus;
  		*type  = PERF_CPU_MAP__CPUS;
  	} else {
  		*size += size_mask;
  		*type  = PERF_CPU_MAP__MASK;
  	}
  
  	*size += sizeof(struct cpu_map_data);
  	*size = PERF_ALIGN(*size, sizeof(u64));
  	return zalloc(*size);
  }
  
  void cpu_map_data__synthesize(struct cpu_map_data *data, struct cpu_map *map,
  			      u16 type, int max)
  {
  	data->type = type;
  
  	switch (type) {
  	case PERF_CPU_MAP__CPUS:
  		synthesize_cpus((struct cpu_map_entries *) data->data, map);
  		break;
  	case PERF_CPU_MAP__MASK:
  		synthesize_mask((struct cpu_map_mask *) data->data, map, max);
  	default:
  		break;
  	};
  }
  
  static struct cpu_map_event* cpu_map_event__new(struct cpu_map *map)
  {
  	size_t size = sizeof(struct cpu_map_event);
  	struct cpu_map_event *event;
  	int max;
  	u16 type;
  
  	event = cpu_map_data__alloc(map, &size, &type, &max);
  	if (!event)
  		return NULL;
  
  	event->header.type = PERF_RECORD_CPU_MAP;
  	event->header.size = size;
  	event->data.type   = type;
  
  	cpu_map_data__synthesize(&event->data, map, type, max);
  	return event;
  }
  
  int perf_event__synthesize_cpu_map(struct perf_tool *tool,
  				   struct cpu_map *map,
  				   perf_event__handler_t process,
  				   struct machine *machine)
  {
  	struct cpu_map_event *event;
  	int err;
  
  	event = cpu_map_event__new(map);
  	if (!event)
  		return -ENOMEM;
  
  	err = process(tool, (union perf_event *) event, NULL, machine);
  
  	free(event);
  	return err;
  }
  
  int perf_event__synthesize_stat_config(struct perf_tool *tool,
  				       struct perf_stat_config *config,
  				       perf_event__handler_t process,
  				       struct machine *machine)
  {
  	struct stat_config_event *event;
  	int size, i = 0, err;
  
  	size  = sizeof(*event);
  	size += (PERF_STAT_CONFIG_TERM__MAX * sizeof(event->data[0]));
  
  	event = zalloc(size);
  	if (!event)
  		return -ENOMEM;
  
  	event->header.type = PERF_RECORD_STAT_CONFIG;
  	event->header.size = size;
  	event->nr          = PERF_STAT_CONFIG_TERM__MAX;
  
  #define ADD(__term, __val)					\
  	event->data[i].tag = PERF_STAT_CONFIG_TERM__##__term;	\
  	event->data[i].val = __val;				\
  	i++;
  
  	ADD(AGGR_MODE,	config->aggr_mode)
  	ADD(INTERVAL,	config->interval)
  	ADD(SCALE,	config->scale)
  
  	WARN_ONCE(i != PERF_STAT_CONFIG_TERM__MAX,
  		  "stat config terms unbalanced\n");
  #undef ADD
  
  	err = process(tool, (union perf_event *) event, NULL, machine);
  
  	free(event);
  	return err;
  }
  
  int perf_event__synthesize_stat(struct perf_tool *tool,
  				u32 cpu, u32 thread, u64 id,
  				struct perf_counts_values *count,
  				perf_event__handler_t process,
  				struct machine *machine)
  {
  	struct stat_event event;
  
  	event.header.type = PERF_RECORD_STAT;
  	event.header.size = sizeof(event);
  	event.header.misc = 0;
  
  	event.id        = id;
  	event.cpu       = cpu;
  	event.thread    = thread;
  	event.val       = count->val;
  	event.ena       = count->ena;
  	event.run       = count->run;
  
  	return process(tool, (union perf_event *) &event, NULL, machine);
  }
  
  int perf_event__synthesize_stat_round(struct perf_tool *tool,
  				      u64 evtime, u64 type,
  				      perf_event__handler_t process,
  				      struct machine *machine)
  {
  	struct stat_round_event event;
  
  	event.header.type = PERF_RECORD_STAT_ROUND;
  	event.header.size = sizeof(event);
  	event.header.misc = 0;
  
  	event.time = evtime;
  	event.type = type;
  
  	return process(tool, (union perf_event *) &event, NULL, machine);
  }
  
  void perf_event__read_stat_config(struct perf_stat_config *config,
  				  struct stat_config_event *event)
  {
  	unsigned i;
  
  	for (i = 0; i < event->nr; i++) {
  
  		switch (event->data[i].tag) {
  #define CASE(__term, __val)					\
  		case PERF_STAT_CONFIG_TERM__##__term:		\
  			config->__val = event->data[i].val;	\
  			break;
  
  		CASE(AGGR_MODE, aggr_mode)
  		CASE(SCALE,     scale)
  		CASE(INTERVAL,  interval)
  #undef CASE
  		default:
  			pr_warning("unknown stat config term %" PRIu64 "\n",
  				   event->data[i].tag);
  		}
  	}
  }
  
  size_t perf_event__fprintf_comm(union perf_event *event, FILE *fp)
  {
  	const char *s;
  
  	if (event->header.misc & PERF_RECORD_MISC_COMM_EXEC)
  		s = " exec";
  	else
  		s = "";
  
  	return fprintf(fp, "%s: %s:%d/%d\n", s, event->comm.comm, event->comm.pid, event->comm.tid);
  }
  
  size_t perf_event__fprintf_namespaces(union perf_event *event, FILE *fp)
  {
  	size_t ret = 0;
  	struct perf_ns_link_info *ns_link_info;
  	u32 nr_namespaces, idx;
  
  	ns_link_info = event->namespaces.link_info;
  	nr_namespaces = event->namespaces.nr_namespaces;
  
  	ret += fprintf(fp, " %d/%d - nr_namespaces: %u\n\t\t[",
  		       event->namespaces.pid,
  		       event->namespaces.tid,
  		       nr_namespaces);
  
  	for (idx = 0; idx < nr_namespaces; idx++) {
  		if (idx && (idx % 4 == 0))
  			ret += fprintf(fp, "\n\t\t ");
  
  		ret  += fprintf(fp, "%u/%s: %" PRIu64 "/%#" PRIx64 "%s", idx,
  				perf_ns__name(idx), (u64)ns_link_info[idx].dev,
  				(u64)ns_link_info[idx].ino,
  				((idx + 1) != nr_namespaces) ? ", " : "]\n");
  	}
  
  	return ret;
  }
  
  int perf_event__process_comm(struct perf_tool *tool __maybe_unused,
  			     union perf_event *event,
  			     struct perf_sample *sample,
  			     struct machine *machine)
  {
  	return machine__process_comm_event(machine, event, sample);
  }
  
  int perf_event__process_namespaces(struct perf_tool *tool __maybe_unused,
  				   union perf_event *event,
  				   struct perf_sample *sample,
  				   struct machine *machine)
  {
  	return machine__process_namespaces_event(machine, event, sample);
  }
  
  int perf_event__process_lost(struct perf_tool *tool __maybe_unused,
  			     union perf_event *event,
  			     struct perf_sample *sample,
  			     struct machine *machine)
  {
  	return machine__process_lost_event(machine, event, sample);
  }
  
  int perf_event__process_aux(struct perf_tool *tool __maybe_unused,
  			    union perf_event *event,
  			    struct perf_sample *sample __maybe_unused,
  			    struct machine *machine)
  {
  	return machine__process_aux_event(machine, event);
  }
  
  int perf_event__process_itrace_start(struct perf_tool *tool __maybe_unused,
  				     union perf_event *event,
  				     struct perf_sample *sample __maybe_unused,
  				     struct machine *machine)
  {
  	return machine__process_itrace_start_event(machine, event);
  }
  
  int perf_event__process_lost_samples(struct perf_tool *tool __maybe_unused,
  				     union perf_event *event,
  				     struct perf_sample *sample,
  				     struct machine *machine)
  {
  	return machine__process_lost_samples_event(machine, event, sample);
  }
  
  int perf_event__process_switch(struct perf_tool *tool __maybe_unused,
  			       union perf_event *event,
  			       struct perf_sample *sample __maybe_unused,
  			       struct machine *machine)
  {
  	return machine__process_switch_event(machine, event);
  }
  
  int perf_event__process_ksymbol(struct perf_tool *tool __maybe_unused,
  				union perf_event *event,
  				struct perf_sample *sample __maybe_unused,
  				struct machine *machine)
  {
  	return machine__process_ksymbol(machine, event, sample);
  }
  
  int perf_event__process_bpf_event(struct perf_tool *tool __maybe_unused,
  				  union perf_event *event,
  				  struct perf_sample *sample __maybe_unused,
  				  struct machine *machine)
  {
  	return machine__process_bpf_event(machine, event, sample);
  }
  
  size_t perf_event__fprintf_mmap(union perf_event *event, FILE *fp)
  {
  	return fprintf(fp, " %d/%d: [%#" PRIx64 "(%#" PRIx64 ") @ %#" PRIx64 "]: %c %s\n",
  		       event->mmap.pid, event->mmap.tid, event->mmap.start,
  		       event->mmap.len, event->mmap.pgoff,
  		       (event->header.misc & PERF_RECORD_MISC_MMAP_DATA) ? 'r' : 'x',
  		       event->mmap.filename);
  }
  
  size_t perf_event__fprintf_mmap2(union perf_event *event, FILE *fp)
  {
  	return fprintf(fp, " %d/%d: [%#" PRIx64 "(%#" PRIx64 ") @ %#" PRIx64
  			   " %02x:%02x %"PRIu64" %"PRIu64"]: %c%c%c%c %s\n",
  		       event->mmap2.pid, event->mmap2.tid, event->mmap2.start,
  		       event->mmap2.len, event->mmap2.pgoff, event->mmap2.maj,
  		       event->mmap2.min, event->mmap2.ino,
  		       event->mmap2.ino_generation,
  		       (event->mmap2.prot & PROT_READ) ? 'r' : '-',
  		       (event->mmap2.prot & PROT_WRITE) ? 'w' : '-',
  		       (event->mmap2.prot & PROT_EXEC) ? 'x' : '-',
  		       (event->mmap2.flags & MAP_SHARED) ? 's' : 'p',
  		       event->mmap2.filename);
  }
  
  size_t perf_event__fprintf_thread_map(union perf_event *event, FILE *fp)
  {
  	struct thread_map *threads = thread_map__new_event(&event->thread_map);
  	size_t ret;
  
  	ret = fprintf(fp, " nr: ");
  
  	if (threads)
  		ret += thread_map__fprintf(threads, fp);
  	else
  		ret += fprintf(fp, "failed to get threads from event\n");
  
  	thread_map__put(threads);
  	return ret;
  }
  
  size_t perf_event__fprintf_cpu_map(union perf_event *event, FILE *fp)
  {
  	struct cpu_map *cpus = cpu_map__new_data(&event->cpu_map.data);
  	size_t ret;
  
  	ret = fprintf(fp, ": ");
  
  	if (cpus)
  		ret += cpu_map__fprintf(cpus, fp);
  	else
  		ret += fprintf(fp, "failed to get cpumap from event\n");
  
  	cpu_map__put(cpus);
  	return ret;
  }
  
  int perf_event__process_mmap(struct perf_tool *tool __maybe_unused,
  			     union perf_event *event,
  			     struct perf_sample *sample,
  			     struct machine *machine)
  {
  	return machine__process_mmap_event(machine, event, sample);
  }
  
  int perf_event__process_mmap2(struct perf_tool *tool __maybe_unused,
  			     union perf_event *event,
  			     struct perf_sample *sample,
  			     struct machine *machine)
  {
  	return machine__process_mmap2_event(machine, event, sample);
  }
  
  size_t perf_event__fprintf_task(union perf_event *event, FILE *fp)
  {
  	return fprintf(fp, "(%d:%d):(%d:%d)\n",
  		       event->fork.pid, event->fork.tid,
  		       event->fork.ppid, event->fork.ptid);
  }
  
  int perf_event__process_fork(struct perf_tool *tool __maybe_unused,
  			     union perf_event *event,
  			     struct perf_sample *sample,
  			     struct machine *machine)
  {
  	return machine__process_fork_event(machine, event, sample);
  }
  
  int perf_event__process_exit(struct perf_tool *tool __maybe_unused,
  			     union perf_event *event,
  			     struct perf_sample *sample,
  			     struct machine *machine)
  {
  	return machine__process_exit_event(machine, event, sample);
  }
  
  size_t perf_event__fprintf_aux(union perf_event *event, FILE *fp)
  {
  	return fprintf(fp, " offset: %#"PRIx64" size: %#"PRIx64" flags: %#"PRIx64" [%s%s%s]\n",
  		       event->aux.aux_offset, event->aux.aux_size,
  		       event->aux.flags,
  		       event->aux.flags & PERF_AUX_FLAG_TRUNCATED ? "T" : "",
  		       event->aux.flags & PERF_AUX_FLAG_OVERWRITE ? "O" : "",
  		       event->aux.flags & PERF_AUX_FLAG_PARTIAL   ? "P" : "");
  }
  
  size_t perf_event__fprintf_itrace_start(union perf_event *event, FILE *fp)
  {
  	return fprintf(fp, " pid: %u tid: %u\n",
  		       event->itrace_start.pid, event->itrace_start.tid);
  }
  
  size_t perf_event__fprintf_switch(union perf_event *event, FILE *fp)
  {
  	bool out = event->header.misc & PERF_RECORD_MISC_SWITCH_OUT;
  	const char *in_out = !out ? "IN         " :
  		!(event->header.misc & PERF_RECORD_MISC_SWITCH_OUT_PREEMPT) ?
  				    "OUT        " : "OUT preempt";
  
  	if (event->header.type == PERF_RECORD_SWITCH)
  		return fprintf(fp, " %s\n", in_out);
  
  	return fprintf(fp, " %s  %s pid/tid: %5u/%-5u\n",
  		       in_out, out ? "next" : "prev",
  		       event->context_switch.next_prev_pid,
  		       event->context_switch.next_prev_tid);
  }
  
  static size_t perf_event__fprintf_lost(union perf_event *event, FILE *fp)
  {
  	return fprintf(fp, " lost %" PRIu64 "\n", event->lost.lost);
  }
  
  size_t perf_event__fprintf_ksymbol(union perf_event *event, FILE *fp)
  {
  	return fprintf(fp, " ksymbol event with addr %" PRIx64 " len %u type %u flags 0x%x name %s\n",
  		       event->ksymbol_event.addr, event->ksymbol_event.len,
  		       event->ksymbol_event.ksym_type,
  		       event->ksymbol_event.flags, event->ksymbol_event.name);
  }
  
  size_t perf_event__fprintf_bpf_event(union perf_event *event, FILE *fp)
  {
  	return fprintf(fp, " bpf event with type %u, flags %u, id %u\n",
  		       event->bpf_event.type, event->bpf_event.flags,
  		       event->bpf_event.id);
  }
  
  size_t perf_event__fprintf(union perf_event *event, FILE *fp)
  {
  	size_t ret = fprintf(fp, "PERF_RECORD_%s",
  			     perf_event__name(event->header.type));
  
  	switch (event->header.type) {
  	case PERF_RECORD_COMM:
  		ret += perf_event__fprintf_comm(event, fp);
  		break;
  	case PERF_RECORD_FORK:
  	case PERF_RECORD_EXIT:
  		ret += perf_event__fprintf_task(event, fp);
  		break;
  	case PERF_RECORD_MMAP:
  		ret += perf_event__fprintf_mmap(event, fp);
  		break;
  	case PERF_RECORD_NAMESPACES:
  		ret += perf_event__fprintf_namespaces(event, fp);
  		break;
  	case PERF_RECORD_MMAP2:
  		ret += perf_event__fprintf_mmap2(event, fp);
  		break;
  	case PERF_RECORD_AUX:
  		ret += perf_event__fprintf_aux(event, fp);
  		break;
  	case PERF_RECORD_ITRACE_START:
  		ret += perf_event__fprintf_itrace_start(event, fp);
  		break;
  	case PERF_RECORD_SWITCH:
  	case PERF_RECORD_SWITCH_CPU_WIDE:
  		ret += perf_event__fprintf_switch(event, fp);
  		break;
  	case PERF_RECORD_LOST:
  		ret += perf_event__fprintf_lost(event, fp);
  		break;
  	case PERF_RECORD_KSYMBOL:
  		ret += perf_event__fprintf_ksymbol(event, fp);
  		break;
  	case PERF_RECORD_BPF_EVENT:
  		ret += perf_event__fprintf_bpf_event(event, fp);
  		break;
  	default:
  		ret += fprintf(fp, "\n");
  	}
  
  	return ret;
  }
  
  int perf_event__process(struct perf_tool *tool __maybe_unused,
  			union perf_event *event,
  			struct perf_sample *sample,
  			struct machine *machine)
  {
  	return machine__process_event(machine, event, sample);
  }
  
  struct map *thread__find_map(struct thread *thread, u8 cpumode, u64 addr,
  			     struct addr_location *al)
  {
  	struct map_groups *mg = thread->mg;
  	struct machine *machine = mg->machine;
  	bool load_map = false;
  
  	al->machine = machine;
  	al->thread = thread;
  	al->addr = addr;
  	al->cpumode = cpumode;
  	al->filtered = 0;
  
  	if (machine == NULL) {
  		al->map = NULL;
  		return NULL;
  	}
  
  	if (cpumode == PERF_RECORD_MISC_KERNEL && perf_host) {
  		al->level = 'k';
  		mg = &machine->kmaps;
  		load_map = true;
  	} else if (cpumode == PERF_RECORD_MISC_USER && perf_host) {
  		al->level = '.';
  	} else if (cpumode == PERF_RECORD_MISC_GUEST_KERNEL && perf_guest) {
  		al->level = 'g';
  		mg = &machine->kmaps;
  		load_map = true;
  	} else if (cpumode == PERF_RECORD_MISC_GUEST_USER && perf_guest) {
  		al->level = 'u';
  	} else {
  		al->level = 'H';
  		al->map = NULL;
  
  		if ((cpumode == PERF_RECORD_MISC_GUEST_USER ||
  			cpumode == PERF_RECORD_MISC_GUEST_KERNEL) &&
  			!perf_guest)
  			al->filtered |= (1 << HIST_FILTER__GUEST);
  		if ((cpumode == PERF_RECORD_MISC_USER ||
  			cpumode == PERF_RECORD_MISC_KERNEL) &&
  			!perf_host)
  			al->filtered |= (1 << HIST_FILTER__HOST);
  
  		return NULL;
  	}
  
  	al->map = map_groups__find(mg, al->addr);
  	if (al->map != NULL) {
  		/*
  		 * Kernel maps might be changed when loading symbols so loading
  		 * must be done prior to using kernel maps.
  		 */
  		if (load_map)
  			map__load(al->map);
  		al->addr = al->map->map_ip(al->map, al->addr);
  	}
  
  	return al->map;
  }
  
  /*
   * For branch stacks or branch samples, the sample cpumode might not be correct
   * because it applies only to the sample 'ip' and not necessary to 'addr' or
   * branch stack addresses. If possible, use a fallback to deal with those cases.
   */
  struct map *thread__find_map_fb(struct thread *thread, u8 cpumode, u64 addr,
  				struct addr_location *al)
  {
  	struct map *map = thread__find_map(thread, cpumode, addr, al);
  	struct machine *machine = thread->mg->machine;
  	u8 addr_cpumode = machine__addr_cpumode(machine, cpumode, addr);
  
  	if (map || addr_cpumode == cpumode)
  		return map;
  
  	return thread__find_map(thread, addr_cpumode, addr, al);
  }
  
  struct symbol *thread__find_symbol(struct thread *thread, u8 cpumode,
  				   u64 addr, struct addr_location *al)
  {
  	al->sym = NULL;
  	if (thread__find_map(thread, cpumode, addr, al))
  		al->sym = map__find_symbol(al->map, al->addr);
  	return al->sym;
  }
  
  struct symbol *thread__find_symbol_fb(struct thread *thread, u8 cpumode,
  				      u64 addr, struct addr_location *al)
  {
  	al->sym = NULL;
  	if (thread__find_map_fb(thread, cpumode, addr, al))
  		al->sym = map__find_symbol(al->map, al->addr);
  	return al->sym;
  }
  
  /*
   * Callers need to drop the reference to al->thread, obtained in
   * machine__findnew_thread()
   */
  int machine__resolve(struct machine *machine, struct addr_location *al,
  		     struct perf_sample *sample)
  {
  	struct thread *thread = machine__findnew_thread(machine, sample->pid,
  							sample->tid);
  
  	if (thread == NULL)
  		return -1;
  
  	dump_printf(" ... thread: %s:%d\n", thread__comm_str(thread), thread->tid);
  	thread__find_map(thread, sample->cpumode, sample->ip, al);
  	dump_printf(" ...... dso: %s\n",
  		    al->map ? al->map->dso->long_name :
  			al->level == 'H' ? "[hypervisor]" : "<not found>");
  
  	if (thread__is_filtered(thread))
  		al->filtered |= (1 << HIST_FILTER__THREAD);
  
  	al->sym = NULL;
  	al->cpu = sample->cpu;
  	al->socket = -1;
  	al->srcline = NULL;
  
  	if (al->cpu >= 0) {
  		struct perf_env *env = machine->env;
  
  		if (env && env->cpu)
  			al->socket = env->cpu[al->cpu].socket_id;
  	}
  
  	if (al->map) {
  		struct dso *dso = al->map->dso;
  
  		if (symbol_conf.dso_list &&
  		    (!dso || !(strlist__has_entry(symbol_conf.dso_list,
  						  dso->short_name) ||
  			       (dso->short_name != dso->long_name &&
  				strlist__has_entry(symbol_conf.dso_list,
  						   dso->long_name))))) {
  			al->filtered |= (1 << HIST_FILTER__DSO);
  		}
  
  		al->sym = map__find_symbol(al->map, al->addr);
  	}
  
  	if (symbol_conf.sym_list &&
  		(!al->sym || !strlist__has_entry(symbol_conf.sym_list,
  						al->sym->name))) {
  		al->filtered |= (1 << HIST_FILTER__SYMBOL);
  	}
  
  	return 0;
  }
  
  /*
   * The preprocess_sample method will return with reference counts for the
   * in it, when done using (and perhaps getting ref counts if needing to
   * keep a pointer to one of those entries) it must be paired with
   * addr_location__put(), so that the refcounts can be decremented.
   */
  void addr_location__put(struct addr_location *al)
  {
  	thread__zput(al->thread);
  }
  
  bool is_bts_event(struct perf_event_attr *attr)
  {
  	return attr->type == PERF_TYPE_HARDWARE &&
  	       (attr->config & PERF_COUNT_HW_BRANCH_INSTRUCTIONS) &&
  	       attr->sample_period == 1;
  }
  
  bool sample_addr_correlates_sym(struct perf_event_attr *attr)
  {
  	if (attr->type == PERF_TYPE_SOFTWARE &&
  	    (attr->config == PERF_COUNT_SW_PAGE_FAULTS ||
  	     attr->config == PERF_COUNT_SW_PAGE_FAULTS_MIN ||
  	     attr->config == PERF_COUNT_SW_PAGE_FAULTS_MAJ))
  		return true;
  
  	if (is_bts_event(attr))
  		return true;
  
  	return false;
  }
  
  void thread__resolve(struct thread *thread, struct addr_location *al,
  		     struct perf_sample *sample)
  {
  	thread__find_map_fb(thread, sample->cpumode, sample->addr, al);
  
  	al->cpu = sample->cpu;
  	al->sym = NULL;
  
  	if (al->map)
  		al->sym = map__find_symbol(al->map, al->addr);
  }
  