hlist_del_rcu — deletes entry from hash list without re-initialization
void hlist_del_rcu ( | struct hlist_node * | n); |
list_unhashed on entry does not return true after this,
the entry is in an undefined state. It is useful for RCU based
lockfree traversal.
In particular, it means that we can not poison the forward pointers that may still be used for walking the hash list.
The caller must take whatever precautions are necessary
(such as holding appropriate locks) to avoid racing
with another list-mutation primitive, such as hlist_add_head_rcu
or hlist_del_rcu, running on this same list.
However, it is perfectly legal to run concurrently with
the _rcu list-traversal primitives, such as
hlist_for_each_entry.