list_add_tail_rcu — add a new entry to rcu-protected list
new entry to be added
list head to add it before
Insert a new entry before the specified head. This is useful for implementing queues.
The caller must take whatever precautions are necessary (such as holding appropriate locks) to avoid racing with another list-mutation primitive, such as list_add_tail_rcu or list_del_rcu, running on this same list. However, it is perfectly legal to run concurrently with the _rcu list-traversal primitives, such as list_for_each_entry_rcu.