Currently, all netlink protocol handlers for updating rules, actions and
qdiscs are protected with single global rtnl lock which removes any
possibility for parallelism. This patch set is a first step to remove
rtnl lock dependency from TC rules update path. It updates act API to
use atomic operations, rcu and spinlocks for fine-grained locking. It
also extend API with functions that are needed to update existing
actions for parallel execution.
Outline of changes:
- Change tc action to use atomic reference and bind counters, rcu
mechanism for cookie update.
- Extend action ops API with 'delete' function and 'unlocked' flag.
- Change action API to work with actions in lockless manner based on
primitives implemented in previous patches.
- Extend action API with new functions necessary to implement unlocked
actions.