On Thu, Oct 10, 2013 at 06:50:46PM +0200, Ingo Molnar wrote: > > * Peter Zijlstra <pet...@infradead.org> wrote: > > > On Thu, Oct 10, 2013 at 04:57:38PM +0200, Ingo Molnar wrote: > > > > > So ... why not make it _really_ cheap, i.e. the read lock costing > > > nothing, and tie CPU hotplug to freezing all tasks in the system? > > > > Such that we freeze regular tasks in userspace and kernel tasks in their > > special freezer callback so as to guarantee minimal state? > > Yes, absolutely.
That does add quite a bit of latency to the hotplug operations, which IIRC slows down things like boot, suspend, and resume. Thanx, Paul -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/