On Thu, 1 May 2008, Nick Piggin wrote: > On Wed, Apr 30, 2008 at 12:14:51PM +0100, Hugh Dickins wrote: > > On Wed, 30 Apr 2008, Nick Piggin wrote: > > > > > > Actually, aside, all those smp_wmb() things in pgtable-3level.h can > > > probably go away if we cared: because we could be sneaky and leverage > > > the assumption that top and bottom will always be in the same cacheline > > > and thus should be shielded from memory consistency problems :) > > > > I've sometimes wondered along those lines. But it would need > > interrupts disabled, wouldn't it? And could SMM mess it up? > > And what about another CPU taking the cacheline to modify it > > in between our two accesses? > > Nothing more than could not already happen with the smp_wmb in there, > AFAIKS. Yes, one does wonder just what I was wondering ;) Hugh -- To unsubscribe from this list: send the line "unsubscribe linux-arch" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
