On Mon, Mar 03, 2008 at 04:29:34AM +0100, Nick Piggin wrote: > to something I prefer. Others may not, but I'll post them for debate > anyway.
Sure, thanks! > > I didn't drop invalidate_page, because invalidate_range_begin/end > > would be slower for usages like KVM/GRU (we don't need a begin/end > > there because where invalidate_page is called, the VM holds a > > reference on the page). do_wp_page should also use invalidate_page > > since it can free the page after dropping the PT lock without losing > > any performance (that's not true for the places where invalidate_range > > is called). > > I'm still not completely happy with this. I had a very quick look > at the GRU driver, but I don't see why it can't be implemented > more like the regular TLB model, and have TLB insertions depend on > the linux pte, and do invalidates _after_ restricting permissions > to the pte. > > Ie. I'd still like to get rid of invalidate_range_begin, and get > rid of invalidate calls from places where permissions are relaxed. _begin exists because by the time _end is called, the VM already dropped the reference on the page. This way we can do a single invalidate no matter how large the range is. I don't see ways to remove _begin while still invoking _end a single time for the whole range. > If we can agree on the API, then I don't see any reason why it can't > go into 2.6.25, unless someome wants more time to review it (but > 2.6.25 release should be quite far away still so there should be quite > a bit of time). Cool! ;) ------------------------------------------------------------------------- This SF.net email is sponsored by: Microsoft Defy all challenges. Microsoft(R) Visual Studio 2008. http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ _______________________________________________ kvm-devel mailing list kvm-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/kvm-devel
