- Remove unused variable from create_thread().

- Move kern_thr_*() prototype to <sys/syscallsubr.h> where all the other
  kern_*() prototypes live.

sys/kern/kern_thr.c

@@ -40,6 +40,7 @@ __FBSDID("$FreeBSD$");
 #include <sys/sched.h>
 #include <sys/sysctl.h>
 #include <sys/smp.h>
+#include <sys/syscallsubr.h>
 #include <sys/sysent.h>
 #include <sys/systm.h>
 #include <sys/sysproto.h>
@@ -143,7 +144,6 @@ create_thread(struct thread *td, mcontext_t *ctx,
 	stack_t stack;
 	struct thread *newtd;
 	struct proc *p;
-	long id;
 	int error;
 
 	error = 0;
@@ -183,7 +183,6 @@ create_thread(struct thread *td, mcontext_t *ctx,
 	 * its storage, because child thread may exit quickly and
 	 * memory is freed before parent thread can access it.
 	 */
-	id = newtd->td_tid;
 	if ((child_tid != NULL &&
 	    suword_lwpid(child_tid, newtd->td_tid)) ||
 	    (parent_tid != NULL &&

sys/sys/syscallsubr.h

@@ -48,6 +48,7 @@ struct stat;
 struct kevent;
 struct kevent_copyops;
 struct sendfile_args;
+struct thr_param;
 
 int	kern___getcwd(struct thread *td, u_char *buf, enum uio_seg bufseg,
 	    u_int buflen);
@@ -168,6 +169,8 @@ int	kern_statfs(struct thread *td, char *path, enum uio_seg pathseg,
 	    struct statfs *buf);
 int	kern_symlink(struct thread *td, char *path, char *link,
 	    enum uio_seg segflg);
+int	kern_thr_new(struct thread *td, struct thr_param *param);
+int	kern_thr_suspend(struct thread *td, struct timespec *tsp);
 int	kern_truncate(struct thread *td, char *path, enum uio_seg pathseg,
 	    off_t length);
 int	kern_unlink(struct thread *td, char *path, enum uio_seg pathseg);

sys/sys/thr.h

@@ -64,10 +64,7 @@ int thr_kill(long id, int sig);
 int thr_suspend(const struct timespec *timeout);
 int thr_wake(long id);
 int thr_set_name(long id, const char *name);
-#else
-struct thread;
-int kern_thr_new(struct thread *td, struct thr_param *param);
-int kern_thr_suspend(struct thread *, struct timespec *);
+
 #endif /* !_KERNEL */
 
 #endif /* ! _SYS_THR_H_ */