mm: NUMA aware alloc_thread_info_node()

[deliverable/linux.git] / kernel / rcupdate.c

diff --git a/kernel/rcupdate.c b/kernel/rcupdate.c
index a23a57a976d1a46f69cb2c32ecc38dd78e5e8b08..f3240e987928ca9630b15d39784180339c8727dd 100644 (file)
--- a/kernel/rcupdate.c
+++ b/kernel/rcupdate.c
@@ -214,11 +214,12 @@ static int rcuhead_fixup_free(void *addr, enum debug_obj_state state)
                 * Ensure that queued callbacks are all executed.
                 * If we detect that we are nested in a RCU read-side critical
                 * section, we should simply fail, otherwise we would deadlock.
+                * Note that the machinery to reliably determine whether
+                * or not we are in an RCU read-side critical section
+                * exists only in the preemptible RCU implementations
+                * (TINY_PREEMPT_RCU and TREE_PREEMPT_RCU), which is why
+                * DEBUG_OBJECTS_RCU_HEAD is disallowed if !PREEMPT.
                 */
-#ifndef CONFIG_PREEMPT
-               WARN_ON(1);
-               return 0;
-#else
                if (rcu_preempt_depth() != 0 || preempt_count() != 0 ||
                    irqs_disabled()) {
                        WARN_ON(1);
@@ -229,7 +230,6 @@ static int rcuhead_fixup_free(void *addr, enum debug_obj_state state)
                rcu_barrier_bh();
                debug_object_free(head, &rcuhead_debug_descr);
                return 1;
-#endif
        default:
                return 0;
        }