On Wed, Feb 20, 2008 at 12:11:57AM +0100, Nick Piggin wrote: > On Tue, Feb 19, 2008 at 02:58:51PM +0100, Andrea Arcangeli wrote: > > On Tue, Feb 19, 2008 at 09:43:57AM +0100, Nick Piggin wrote: > > > anything when changing the pte to be _more_ permissive, and I don't > > > > Note that in my patch the invalidate_pages in mprotect can be > > trivially switched to a mprotect_pages with proper params. This will > > prevent page faults completely in the secondary MMU (there will only > > be tlb misses after the tlb flush just like for the core linux pte), > > and it'll allow all the secondary MMU pte blocks (512/1024 at time > > with my PT lock design) to be updated to have proper permissions > > matching the core linux pte. > > Sorry, I realise I still didn't get this through my head yet (and also > have not seen your patch recently). So I don't know exactly what you > are doing... > > But why does _anybody_ (why does Christoph's patches) need to invalidate > when they are going to be more permissive? This should be done lazily by > the driver, I would have thought.
Agree. Although for most real applications, the performance difference is probably negligible. --- jack -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
