Re: [PATCH RFC 3/9] RCU: Preemptible RCU

[Paul E. McKenney]

On Mon, Oct 01, 2007 at 03:09:16PM -0700, Davide Libenzi wrote:
> On Mon, 1 Oct 2007, Paul E. McKenney wrote:
> 
> > That would indeed be one approach that CPU designers could take to
> > avoid being careless or sadistic.  ;-)
> 
> That'd be the easier (unique maybe) approach too for them, from an silicon 
> complexity POV. Distinguishing between different CPUs stores once inside a 
> shared store buffer, would require tagging them in some way. That'd defeat 
> most of the pros of having a shared store buffer ;)

Tagging requires but one bit per entry.  Depends on the workload -- if
lots of barriers, bursty stores and little sharing, tagging might win.
If lots of sharing, then your suggested approach might win.

						Thanx, Paul
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/