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Commit ca6c41c5 authored by David Ahern's avatar David Ahern Committed by Arnaldo Carvalho de Melo
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perf tools: Fix ppid for synthesized fork events 



363b785f added synthesized fork events and set a thread's parent id to
itself. Since we are already processing /proc/<pid>/status the ppid can
be determined properly. Make it so.

Signed-off-by: default avatarDavid Ahern <dsahern@gmail.com>
Acked-by: default avatarDon Zickus <dzickus@redhat.com>
Acked-by: default avatarJiri Olsa <jolsa@kernel.org>
Cc: Joe Mario <jmario@redhat.com>
Link: http://lkml.kernel.org/r/1427747758-18510-2-git-send-email-dsahern@gmail.com


Signed-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
parent 5aa0b030

tools/perf/util/event.c

+50 −33
Original line number Diff line number Diff line
@@ -51,29 +51,32 @@ static struct perf_sample synth_sample = { 


/*

 * Assumes that the first 4095 bytes of /proc/pid/stat contains

 * the comm and tgid.

 * the comm, tgid and ppid.

 */

static pid_t perf_event__get_comm_tgid(pid_t pid, char *comm, size_t len)

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, n;

	pid_t tgid = -1;

	char *nl, *name, *tgids;

	char *nl, *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 0;

		return -1;

	}



	n = read(fd, bf, sizeof(bf) - 1);

	close(fd);

	if (n <= 0) {

		pr_warning("Couldn't get COMM and tgid for pid %d\n",

		pr_warning("Couldn't get COMM, tigd and ppid for pid %d\n",

			   pid);

		return -1;

	}
@@ -81,6 +84,7 @@ static pid_t perf_event__get_comm_tgid(pid_t pid, char *comm, size_t len) 


	name = strstr(bf, "Name:");

	tgids = strstr(bf, "Tgid:");

	ppids = strstr(bf, "PPid:");



	if (name) {

		name += 5;  /* strlen("Name:") */
@@ -103,32 +107,45 @@ static pid_t perf_event__get_comm_tgid(pid_t pid, char *comm, size_t len) 


	if (tgids) {

		tgids += 5;  /* strlen("Tgid:") */

		tgid = atoi(tgids);

		*tgid = atoi(tgids);

	} else {

		pr_debug("Tgid: string not found for pid %d\n", pid);

	}



	return tgid;

	if (ppids) {

		ppids += 5;  /* strlen("PPid:") */

		*ppid = atoi(ppids);

	} else {

		pr_debug("PPid: string not found for pid %d\n", pid);

	}



static pid_t perf_event__prepare_comm(union perf_event *event, pid_t pid,

					 struct machine *machine)

	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;

	pid_t tgid;



	*ppid = -1;



	memset(&event->comm, 0, sizeof(event->comm));



	if (machine__is_host(machine))

		tgid = perf_event__get_comm_tgid(pid, event->comm.comm,

						 sizeof(event->comm.comm));

	else

		tgid = machine->pid;

	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)

		goto out;

	if (*tgid < 0)

		return -1;



	event->comm.pid = tgid;

	event->comm.pid = *tgid;

	event->comm.header.type = PERF_RECORD_COMM;



	size = strlen(event->comm.comm) + 1;
@@ -138,8 +155,8 @@ static pid_t perf_event__prepare_comm(union perf_event *event, pid_t pid, 
				(sizeof(event->comm.comm) - size) +

				machine->id_hdr_size);

	event->comm.tid = pid;

out:

	return tgid;



	return 0;

}



static pid_t perf_event__synthesize_comm(struct perf_tool *tool,
@@ -147,27 +164,27 @@ static pid_t perf_event__synthesize_comm(struct perf_tool *tool, 
					 perf_event__handler_t process,

					 struct machine *machine)

{

	pid_t tgid = perf_event__prepare_comm(event, pid, machine);

	pid_t tgid, ppid;



	if (tgid == -1)

		goto out;

	if (perf_event__prepare_comm(event, pid, machine, &tgid, &ppid) != 0)

		return -1;



	if (process(tool, event, &synth_sample, machine) != 0)

		return -1;



out:

	return tgid;

}



static int perf_event__synthesize_fork(struct perf_tool *tool,

				       union perf_event *event, pid_t pid,

				       pid_t tgid, perf_event__handler_t process,

				       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);



	event->fork.ppid = tgid;

	event->fork.ptid = tgid;

	event->fork.ppid = ppid;

	event->fork.ptid = ppid;

	event->fork.pid  = tgid;

	event->fork.tid  = pid;

	event->fork.header.type = PERF_RECORD_FORK;
@@ -359,7 +376,7 @@ static int __event__synthesize_thread(union perf_event *comm_event, 
	char filename[PATH_MAX];

	DIR *tasks;

	struct dirent dirent, *next;

	pid_t tgid;

	pid_t tgid, ppid;



	/* special case: only send one comm event using passed in pid */

	if (!full) {
@@ -394,12 +411,12 @@ static int __event__synthesize_thread(union perf_event *comm_event, 
		if (*end)

			continue;



		tgid = perf_event__prepare_comm(comm_event, _pid, machine);

		if (tgid == -1)

		if (perf_event__prepare_comm(comm_event, _pid, machine,

					     &tgid, &ppid) != 0)

			return -1;



		if (perf_event__synthesize_fork(tool, fork_event, _pid, tgid,

						process, machine) < 0)

						ppid, process, machine) < 0)

			return -1;

		/*

		 * Send the prepared comm event