rcutorture: Add irqs-disabled test for call_rcu()

Mutation testing carried out by Iftekhar Ahmed of Oregon State
University showed that rcutorture is failing to test invocations
of call_rcu() having interrupts disabled.  This commit therefore
adds interrupt disabling around one of the existing invocations
of call_rcu() (and friends).

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>

diff --git a/kernel/rcu/rcutorture.c b/kernel/rcu/rcutorture.c
index 633a68a094402c0cde21b5e2f2b5418c131bb1cc..084a28a732eb7ec53f3a0c055d6be031bb462941 100644 (file)
--- a/kernel/rcu/rcutorture.c
+++ b/kernel/rcu/rcutorture.c
@@ -1478,7 +1478,9 @@ static int rcu_torture_barrier_cbs(void *arg)
                 * The above smp_load_acquire() ensures barrier_phase load
                 * is ordered before the folloiwng ->call().
                 */
+               local_irq_disable(); /* Just to test no-irq call_rcu(). */
                cur_ops->call(&rcu, rcu_torture_barrier_cbf);
+               local_irq_enable();
                if (atomic_dec_and_test(&barrier_cbs_count))
                        wake_up(&barrier_wq);
        } while (!torture_must_stop());