const pid_t gpid = task_pid_nr(current);
        static const int tomoyo_buffer_len = 4096;
        char *buffer = kmalloc(tomoyo_buffer_len, GFP_NOFS);
+       pid_t ppid;
        if (!buffer)
                return NULL;
        do_gettimeofday(&tv);
+       rcu_read_lock();
+       ppid = task_tgid_vnr(current->real_parent);
+       rcu_read_unlock();
        snprintf(buffer, tomoyo_buffer_len - 1,
                 "#timestamp=%lu profile=%u mode=%s (global-pid=%u)"
                 " task={ pid=%u ppid=%u uid=%u gid=%u euid=%u"
                 " egid=%u suid=%u sgid=%u fsuid=%u fsgid=%u }",
                 tv.tv_sec, r->profile, tomoyo_mode[r->mode], gpid,
-                (pid_t) sys_getpid(), (pid_t) sys_getppid(),
+                task_tgid_vnr(current), ppid,
                 current_uid(), current_gid(), current_euid(),
                 current_egid(), current_suid(), current_sgid(),
                 current_fsuid(), current_fsgid());
 
 
 /********** Function prototypes. **********/
 
-extern asmlinkage long sys_getpid(void);
-extern asmlinkage long sys_getppid(void);
-
 /* Check whether the given string starts with the given keyword. */
 bool tomoyo_str_starts(char **src, const char *find);
 /* Get tomoyo_realpath() of current process. */