Userspace RCU Implementatation
by Mathieu Desnoyers and Paul E. McKenney

BUILDING
--------

	make
	make install
	

QUICK START GUIDE
-----------------

Initialization

	Each thread that has reader critical sections (that uses
	rcu_read_lock()/rcu_read_unlock() must first register to the URCU
	library. This is done by calling rcu_register_thread().

Reading

	Reader critical sections must be protected by locating them between
	calls to rcu_read_lock() and rcu_read_unlock(). Inside that lock,
	rcu_dereference() may be called to read an RCU protected pointer.

Writing

	rcu_assign_pointer() and rcu_xchg_pointer() may be called anywhere.
	After, synchronize_rcu() must be called. When it returns, the old values
	are not in usage anymore.


Usage of DEBUG_FULL_MB

	DEBUG_FULL_MB uses full SMP barriers for readers. This eliminates the
	need for signals but results in slower reads.


Usage of DEBUG_YIELD

	DEBUG_YIELD is used to add random delays in the code for testing
	purposes.