On Tue, 25 Sep 2007 18:11:39 -0700 "Paul E. McKenney" <paulmck@xxxxxxxxxxxxxxxxxx> wrote: > On Wed, Sep 26, 2007 at 01:24:47AM +0200, Peter Zijlstra wrote: > > On Tue, 25 Sep 2007 16:02:45 -0400 (EDT) Steven Rostedt > > <rostedt@xxxxxxxxxxx> wrote: > > > > > > This would of course require that synchronize_all_irqs() be in the > > > > RCU code rather than the irq code so that it could access the static > > > > wakeme_after_rcu() definition and the rcu_synchronize structure. > > > > > > > > Thoughts? > > > > > > I do like this better. Anyone else care to comment? > > > > I'm still wondering why the IRQ users cannot user proper RCU as it > > stands: > > Well, that was my initial proposal. ;-) handler: > > rcu_read_lock(); > > foo = rcu_dereference(bar); > > if (foo) > > foo(); > > rcu_read_unlock(); > control routine (!handler) > > vs > > > > rcu_assign(foo, NULL); > > synchronize_rcu(); > > The implicit rcu_read_lock() as placed in handle_IRQ_event() seems > > misplaced. > > OK -- where would you put them instead? I have them covering the > call to the handler, so what am I missing here? in do_hardirq() (-rt) that is specific to threaded interrupts. That said, I'm wondering if we need this whole extra sync_all_irqs() thing. I'm just not getting why IRQ handlers should be an implicit RCU safe context. - To unsubscribe from this list: send the line "unsubscribe linux-rt-users" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
