On Tue, Jan 06, 2009 at 10:44:35PM +0100, Peter Zijlstra wrote:

On Tue, 2009-01-06 at 13:42 -0800, Paul E. McKenney wrote:

quoted

Preemptable RCU needs to be faster.  Got it -- and might have a way
to do it by eliminating the irq disabling and cutting way back on the
number of operations that must be performed.  It would probably still
be necessary to access the task structure.

Or is something other than the raw performance of rcu_read_lock() and
rcu_read_unlock() at issue here?

With Linus' mutex_spin_or_schedule() function the whole - keeping
owner's task_struct alive issue goes away,.. now if only the thing would
boot...

Cool!  And I can relate to the "if only the thing would boot" part.  ;-)

							Thanx, Paul