Re: [PATCH tip/core/rcu 36/55] rcu: Prevent early bootset_need_resched() from __rcu_pending()

[Paul E. McKenney]

On Sun, Oct 16, 2011 at 06:49:15PM -0700, Josh Triplett wrote:
> On Tue, Sep 06, 2011 at 11:00:30AM -0700, Paul E. McKenney wrote:
> > From: Paul E. McKenney <paul.mckenney@xxxxxxxxxx>
> > 
> > There isn't a whole lot of point in poking the scheduler before there
> > are other tasks to switch to.  This commit therefore adds a check
> > for rcu_scheduler_fully_active in __rcu_pending() to suppress any
> > pre-scheduler calls to set_need_resched().  The downside of this approach
> > is additional runtime overhead in a reasonably hot code path.
> 
> If you're concerned about the runtime overhead, this does seem like a
> perfect candidate for jump labels.

I have added this to my todo list, but would welcome a patch.

							Thanx, Paul

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