rcutorture: Remove redundant rcutorture_one_extend() from rcu_torture_one_read()

This commit removes a harmless but potentially confusing invocation of
rcutorture_one_extend() within rcu_torture_one_read().  The immediately
preceding call to rcu_torture_one_read_start() already does this cleanup,
and the other call to rcu_torture_one_read_start() already relies on this.

Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>

Author: paulmckrcu

kernel/rcu/rcutorture.c

@@ -2384,10 +2384,8 @@ static bool rcu_torture_one_read(struct torture_random_state *trsp, long myid)
 	newstate = rcutorture_extend_mask(rtors.readstate, trsp);
 	WARN_ON_ONCE(newstate & RCUTORTURE_RDR_UPDOWN);
 	rcutorture_one_extend(&rtors.readstate, newstate, trsp, rtors.rtrsp++);
-	if (!rcu_torture_one_read_start(&rtors, trsp, myid)) {
-		rcutorture_one_extend(&rtors.readstate, 0, trsp, rtors.rtrsp);
+	if (!rcu_torture_one_read_start(&rtors, trsp, myid))
 		return false;
-	}
 	rtors.rtrsp = rcutorture_loop_extend(&rtors.readstate, trsp, rtors.rtrsp);
 	rcu_torture_one_read_end(&rtors, trsp);
 	return true;