diff options
| -rw-r--r-- | include/linux/rcupdate.h | 14 |
1 files changed, 14 insertions, 0 deletions
diff --git a/include/linux/rcupdate.h b/include/linux/rcupdate.h index f1f1bc39346b..4912c953cab7 100644 --- a/include/linux/rcupdate.h +++ b/include/linux/rcupdate.h @@ -554,6 +554,20 @@ static inline void rcu_preempt_sleep_check(void) (p) = (typeof(*v) __force space *)(v); \ } while (0) +/** + * lockless_dereference() - safely load a pointer for later dereference + * @p: The pointer to load + * + * Similar to rcu_dereference(), but for situations where the pointed-to + * object's lifetime is managed by something other than RCU. That + * "something other" might be reference counting or simple immortality. + */ +#define lockless_dereference(p) \ +({ \ + typeof(p) _________p1 = ACCESS_ONCE(p); \ + smp_read_barrier_depends(); /* Dependency order vs. p above. */ \ + (_________p1); \ +}) /** * rcu_access_pointer() - fetch RCU pointer with no dereferencing |