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>

1 files changed, 2 insertions, 0 deletions

diff --git a/kernel/rcu/rcutorture.c b/kernel/rcu/rcutorture.c
index 633a68a09440..084a28a732eb 100644
--- 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());