Merge Linus master into drm-next

The merge is clean, but the arm build fails afterwards,
due to API changes in the regulator tree.

I've included the patch into the merge to fix the build.

Signed-off-by: Dave Airlie <airlied@redhat.com>

1 files changed, 124 insertions, 66 deletions

diff --git a/tools/perf/util/event.c b/tools/perf/util/event.c
index 6c6d044e959a..ff866c4d2e2f 100644
--- a/tools/perf/util/event.c
+++ b/tools/perf/util/event.c
@@ -49,72 +49,103 @@ static struct perf_sample synth_sample = {
 	.period	   = 1,
 };
 
-static pid_t perf_event__get_comm_tgid(pid_t pid, char *comm, size_t len)
+/*
+ * 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[BUFSIZ];
-	FILE *fp;
-	size_t size = 0;
-	pid_t tgid = -1;
+	char bf[4096];
+	int fd;
+	size_t size = 0, n;
+	char *nl, *name, *tgids, *ppids;
+
+	*tgid = -1;
+	*ppid = -1;
 
 	snprintf(filename, sizeof(filename), "/proc/%d/status", pid);
 
-	fp = fopen(filename, "r");
-	if (fp == NULL) {
+	fd = open(filename, O_RDONLY);
+	if (fd < 0) {
 		pr_debug("couldn't open %s\n", filename);
-		return 0;
+		return -1;
 	}
 
-	while (!comm[0] || (tgid < 0)) {
-		if (fgets(bf, sizeof(bf), fp) == NULL) {
-			pr_warning("couldn't get COMM and pgid, malformed %s\n",
-				   filename);
-			break;
-		}
+	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';
 
-		if (memcmp(bf, "Name:", 5) == 0) {
-			char *name = bf + 5;
-			while (*name && isspace(*name))
-				++name;
-			size = strlen(name) - 1;
-			if (size >= len)
-				size = len - 1;
-			memcpy(comm, name, size);
-			comm[size] = '\0';
-
-		} else if (memcmp(bf, "Tgid:", 5) == 0) {
-			char *tgids = bf + 5;
-			while (*tgids && isspace(*tgids))
-				++tgids;
-			tgid = atoi(tgids);
-		}
+	name = strstr(bf, "Name:");
+	tgids = strstr(bf, "Tgid:");
+	ppids = strstr(bf, "PPid:");
+
+	if (name) {
+		name += 5;  /* strlen("Name:") */
+
+		while (*name && isspace(*name))
+			++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);
 	}
 
-	fclose(fp);
+	if (tgids) {
+		tgids += 5;  /* strlen("Tgid:") */
+		*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);
+	}
+
+	return 0;
 }
 
-static 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)
+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;
@@ -125,23 +156,45 @@ static pid_t perf_event__synthesize_comm(struct perf_tool *tool,
 				machine->id_hdr_size);
 	event->comm.tid = pid;
 
+	return 0;
+}
+
+static 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 (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);
 
-	/* this is really a clone event but we use fork to synthesize it */
-	event->fork.ppid = tgid;
-	event->fork.ptid = tgid;
+	/*
+	 * 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;
@@ -333,7 +386,8 @@ 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;
+	int rc = 0;
 
 	/* special case: only send one comm event using passed in pid */
 	if (!full) {
@@ -361,34 +415,38 @@ static int __event__synthesize_thread(union perf_event *comm_event,
 
 	while (!readdir_r(tasks, &dirent, &next) && next) {
 		char *end;
-		int rc = 0;
 		pid_t _pid;
 
 		_pid = strtol(dirent.d_name, &end, 10);
 		if (*end)
 			continue;
 
-		tgid = perf_event__synthesize_comm(tool, comm_event, _pid,
-						   process, machine);
-		if (tgid == -1)
-			return -1;
+		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;
+		/*
+		 * Send the prepared comm event
+		 */
+		if (process(tool, comm_event, &synth_sample, machine) != 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);
-		} else {
-			/* only fork the tid's map, to save time */
-			rc = perf_event__synthesize_fork(tool, fork_event, _pid, tgid,
-						 process, machine);
+			if (rc)
+				break;
 		}
-
-		if (rc)
-			return rc;
 	}
 
 	closedir(tasks);
-	return 0;
+	return rc;
 }
 
 int perf_event__synthesize_thread_map(struct perf_tool *tool,
@@ -615,7 +673,7 @@ size_t perf_event__fprintf_comm(union perf_event *event, FILE *fp)
 	else
 		s = "";
 
-	return fprintf(fp, "%s: %s:%d\n", s, event->comm.comm, event->comm.tid);
+	return fprintf(fp, "%s: %s:%d/%d\n", s, event->comm.comm, event->comm.pid, event->comm.tid);
 }
 
 int perf_event__process_comm(struct perf_tool *tool __maybe_unused,