diff options
Diffstat (limited to 'include/linux/rcupdate.h')
| -rw-r--r-- | include/linux/rcupdate.h | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/include/linux/rcupdate.h b/include/linux/rcupdate.h index 39cbb889e20d..00ad28168ef0 100644 --- a/include/linux/rcupdate.h +++ b/include/linux/rcupdate.h @@ -911,6 +911,14 @@ static inline notrace void rcu_read_unlock_sched_notrace(void) * rcu_assign_pointer() is a very bad thing that results in * impossible-to-diagnose memory corruption. So please be careful. * See the RCU_INIT_POINTER() comment header for details. + * + * Note that rcu_assign_pointer() evaluates each of its arguments only + * once, appearances notwithstanding. One of the "extra" evaluations + * is in typeof() and the other visible only to sparse (__CHECKER__), + * neither of which actually execute the argument. As with most cpp + * macros, this execute-arguments-only-once property is important, so + * please be careful when making changes to rcu_assign_pointer() and the + * other macros that it invokes. */ #define rcu_assign_pointer(p, v) \ __rcu_assign_pointer((p), (v), __rcu) |