On Tue, Apr 08, 2014 at 10:01:39AM -0700, Linus Torvalds wrote: > On Tue, Apr 8, 2014 at 9:46 AM, Mel Gorman <mgorman@xxxxxxx> wrote: > > > > If you are ok with leaving _PAGE_NUMA as _PAGE_PROTNONE > > NO I AM NOT! > > Dammit, this feature is f*cking brain-damaged. > > My complaint has been (and continues to be): > > - either it is 100% the same as PROTNONE, in which case thjat > _PAGE_NUMA bit had better go away, and you just use the protnone > helpers! > In which case we'd still use VMAs to distinguish between PROTNONE faults and NUMA hinting faults. We may still need some special casing. It's plan b but not my preferred solution at this time. > - if it's not the same as PROTNONE, then it damn well needs a different bit. > With this series applied _PAGE_NUMA != _PAGE_PROTNONE. > You can't have it both ways. You guys tried. The Xen case shows that > trying to distinguish the two DOES NOT WORK. But even apart from the > Xen case, it was just a confusing hell. > Which is why I responded with a series that used a different bit instead of more discussions that would reach the same conclusion. > Like Yoda said: "Either they are the same or they are not. There is no 'try'". > > So pick one solution. Don't try to pick the mixed-up half-way case > that is a disaster and makes no sense. > I picked a solution. The posted series uses a different bit. -- Mel Gorman SUSE Labs -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>