On Mon, 2011-01-17 at 23:12 -0800, Hugh Dickins wrote:

21/21 mm-optimize_page_lock_anon_vma_fast-path.patch
      I certainly see the call for this patch, I want to eliminate those
      doubled atomics too.  This appears correct to me, and I've not dreamt
      up an alternative; but I do dislike it, and I suspect you don't like
      it much either.  I'm ambivalent about it, would love a better patch. 

Spot on, maybe a one of our keen readers will have a bright idea.. :-)