[PATCH 05/26] trace-cmd: Move find_tasks() into add_guest()

[Steven Rostedt <rostedt@xxxxxxxxxxx>]

From: "Steven Rostedt (Google)" <rostedt@xxxxxxxxxxx>

In order to simplify the logic a bit, move the find_tasks() code (to find
the PIDs on the host that map to the guest) into the add_guest() function
where the guest is first added.

Link: https://lore.kernel.org/linux-trace-devel/20220428150635.789051-4-rostedt@xxxxxxxxxxx

Signed-off-by: Steven Rostedt (Google) <rostedt@xxxxxxxxxxx>
---
 tracecmd/trace-record.c | 35 -----------------------------------
 tracecmd/trace-vm.c     | 33 +++++++++++++++++++++++++++++++++
 2 files changed, 33 insertions(+), 35 deletions(-)

diff --git a/tracecmd/trace-record.c b/tracecmd/trace-record.c
index 67ad1208f90c..5f7ac15dd80a 100644
--- a/tracecmd/trace-record.c
+++ b/tracecmd/trace-record.c
@@ -3215,38 +3215,6 @@ static int do_accept(int sd)
 	return -1;
 }
 
-/* Find all the tasks associated with the guest pid */
-static void find_tasks(struct trace_guest *guest)
-{
-	struct dirent *dent;
-	char *path;
-	DIR *dir;
-	int ret;
-	int tasks = 0;
-
-	ret = asprintf(&path, "/proc/%d/task", guest->pid);
-	if (ret < 0)
-		return;
-
-	dir = opendir(path);
-	free(path);
-	if (!dir)
-		return;
-
-	while ((dent = readdir(dir))) {
-		int *pids;
-		if (!(dent->d_type == DT_DIR && is_digits(dent->d_name)))
-			continue;
-		pids = realloc(guest->task_pids, sizeof(int) * (tasks + 2));
-		if (!pids)
-			break;
-		pids[tasks++] = strtol(dent->d_name, NULL, 0);
-		pids[tasks] = -1;
-		guest->task_pids = pids;
-	}
-	closedir(dir);
-}
-
 static char *parse_guest_name(char *gname, int *cid, int *port,
 			      struct addrinfo **res)
 {
@@ -3287,9 +3255,6 @@ static char *parse_guest_name(char *gname, int *cid, int *port,
 		guest = trace_get_guest(*cid, gname);
 	if (guest) {
 		*cid = guest->cid;
-		/* Mapping not found, search for them */
-		if (!guest->cpu_pid)
-			find_tasks(guest);
 		return guest->name;
 	}
 
diff --git a/tracecmd/trace-vm.c b/tracecmd/trace-vm.c
index 4b4e039bd2cb..84f28824e3c5 100644
--- a/tracecmd/trace-vm.c
+++ b/tracecmd/trace-vm.c
@@ -54,6 +54,38 @@ bool trace_have_guests_pid(void)
 	return true;
 }
 
+/* Find all the tasks associated with the guest pid */
+static void find_tasks(struct trace_guest *guest)
+{
+	struct dirent *dent;
+	char *path;
+	DIR *dir;
+	int ret;
+	int tasks = 0;
+
+	ret = asprintf(&path, "/proc/%d/task", guest->pid);
+	if (ret < 0)
+		return;
+
+	dir = opendir(path);
+	free(path);
+	if (!dir)
+		return;
+
+	while ((dent = readdir(dir))) {
+		int *pids;
+		if (!(dent->d_type == DT_DIR && is_digits(dent->d_name)))
+			continue;
+		pids = realloc(guest->task_pids, sizeof(int) * (tasks + 2));
+		if (!pids)
+			break;
+		pids[tasks++] = strtol(dent->d_name, NULL, 0);
+		pids[tasks] = -1;
+		guest->task_pids = pids;
+	}
+	closedir(dir);
+}
+
 static void find_pid_by_cid(struct trace_guest *guest);
 
 static struct trace_guest *add_guest(unsigned int cid, const char *name)
@@ -74,6 +106,7 @@ static struct trace_guest *add_guest(unsigned int cid, const char *name)
 	guest->pid = -1;
 
 	find_pid_by_cid(guest);
+	find_tasks(guest);
 
 	return guest;
 }
-- 
2.35.1