Merge tag 'hwspinlock-3.10' of git://git.kernel.org/pub/scm/linux/kernel/git/ohad...
[cascardo/linux.git] / Documentation / RCU / lockdep.txt
index a102d4b..cd83d23 100644 (file)
@@ -64,6 +64,11 @@ checking of rcu_dereference() primitives:
                but retain the compiler constraints that prevent duplicating
                or coalescsing.  This is useful when when testing the
                value of the pointer itself, for example, against NULL.
+       rcu_access_index(idx):
+               Return the value of the index and omit all barriers, but
+               retain the compiler constraints that prevent duplicating
+               or coalescsing.  This is useful when when testing the
+               value of the index itself, for example, against -1.
 
 The rcu_dereference_check() check expression can be any boolean
 expression, but would normally include a lockdep expression.  However,