rcu: Use WARN_ON_ONCE for DEBUG_OBJECTS_RCU_HEAD warnings

Avoid additional multiple-warning confusion in memory-corruption scenarios.

Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>

diff --git a/kernel/rcupdate.c b/kernel/rcupdate.c
index b54d6d1..7784bd2 100644 (file)
--- a/kernel/rcupdate.c
+++ b/kernel/rcupdate.c
@@ -147,12 +147,12 @@ static int rcuhead_fixup_init(void *addr, enum debug_obj_state state)
                 * attempt any fixup and just print a warning.
                 */
 #ifndef CONFIG_PREEMPT
-               WARN_ON(1);
+               WARN_ON_ONCE(1);
                return 0;
 #endif
                if (rcu_preempt_depth() != 0 || preempt_count() != 0 ||
                    irqs_disabled()) {
-                       WARN_ON(1);
+                       WARN_ON_ONCE(1);
                        return 0;
                }
                rcu_barrier();
@@ -196,12 +196,12 @@ static int rcuhead_fixup_activate(void *addr, enum debug_obj_state state)
                 * attempt any fixup and just print a warning.
                 */
 #ifndef CONFIG_PREEMPT
-               WARN_ON(1);
+               WARN_ON_ONCE(1);
                return 0;
 #endif
                if (rcu_preempt_depth() != 0 || preempt_count() != 0 ||
                    irqs_disabled()) {
-                       WARN_ON(1);
+                       WARN_ON_ONCE(1);
                        return 0;
                }
                rcu_barrier();
@@ -233,12 +233,12 @@ static int rcuhead_fixup_free(void *addr, enum debug_obj_state state)
                 * attempt any fixup and just print a warning.
                 */
 #ifndef CONFIG_PREEMPT
-               WARN_ON(1);
+               WARN_ON_ONCE(1);
                return 0;
 #endif
                if (rcu_preempt_depth() != 0 || preempt_count() != 0 ||
                    irqs_disabled()) {
-                       WARN_ON(1);
+                       WARN_ON_ONCE(1);
                        return 0;
                }
                rcu_barrier();