pid: introduce task_ppid_vnr() helper

Cosmetic change. Unlike all other similar helpers task_ppid_nr_ns() doesn't
have a _vnr() version; add one for consistency.

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Link: https://patch.msgid.link/20251015123633.GB9456@redhat.com
Signed-off-by: Christian Brauner <brauner@kernel.org>

Author: oleg-nesterov

fs/pidfs.c

@@ -446,7 +446,7 @@ static long pidfd_info(struct file *file, unsigned int cmd, unsigned long arg)
 	 * the fields are set correctly, or return ESRCH to avoid providing
 	 * incomplete information. */
 
-	kinfo.ppid = task_ppid_nr_ns(task, NULL);
+	kinfo.ppid = task_ppid_vnr(task);
 	kinfo.tgid = task_tgid_vnr(task);
 	kinfo.pid = task_pid_vnr(task);
 	kinfo.mask |= PIDFD_INFO_PID;

include/linux/pid.h

@@ -310,6 +310,11 @@ static inline pid_t task_ppid_nr_ns(const struct task_struct *tsk, struct pid_na
 	return pid;
 }
 
+static inline pid_t task_ppid_vnr(const struct task_struct *tsk)
+{
+	return task_ppid_nr_ns(tsk, NULL);
+}
+
 static inline pid_t task_ppid_nr(const struct task_struct *tsk)
 {
 	return task_ppid_nr_ns(tsk, &init_pid_ns);