rhashtable: Documentation tweak

Clarify that rhashtable_walk_{stop,start} will not reset the iterator to
the beginning of the hash table.  Confusion between rhashtable_walk_enter
and rhashtable_walk_start has already lead to a bug.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/lib/rhashtable.c b/lib/rhashtable.c
index 707ca5d..ddd7dde 100644
--- a/lib/rhashtable.c
+++ b/lib/rhashtable.c
@@ -735,9 +735,9 @@
  * rhashtable_walk_start - Start a hash table walk
  * @iter:	Hash table iterator
  *
- * Start a hash table walk.  Note that we take the RCU lock in all
- * cases including when we return an error.  So you must always call
- * rhashtable_walk_stop to clean up.
+ * Start a hash table walk at the current iterator position.  Note that we take
+ * the RCU lock in all cases including when we return an error.  So you must
+ * always call rhashtable_walk_stop to clean up.
  *
  * Returns zero if successful.
  *
@@ -846,7 +846,8 @@
  * rhashtable_walk_stop - Finish a hash table walk
  * @iter:	Hash table iterator
  *
- * Finish a hash table walk.
+ * Finish a hash table walk.  Does not reset the iterator to the start of the
+ * hash table.
  */
 void rhashtable_walk_stop(struct rhashtable_iter *iter)
 	__releases(RCU)