On Wed, Jul 22, 2015 at 08:57:45AM -0500, Christoph Lameter wrote: > On Tue, 21 Jul 2015, Paul E. McKenney wrote: > > > > > In the current version, there's also the vmstat_update() that > > > > may schedule delayed work and interrupt the core again > > > > shortly before realizing that there are no more counter updates > > > > happening, at which point it quiesces. Currently we handle > > > > this in cpu_isolated mode simply by spinning and waiting for > > > > the timer interrupts to complete. > > > > > > Perhaps we should fix that? > > > > Didn't Christoph Lameter fix this? Or is this an additional problem? > > Well the vmstat update must realize first that there are no outstanding > updates before switching itself off. So typically there is one extra tick. > But we could add another function that will simply fold the differential > immediately and turn the kworker task in the expectation that the > processor will stay quiet. Got it, thank you! Thanx, Paul -- To unsubscribe from this list: send the line "unsubscribe linux-api" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
