On 09/02/2014 12:05 PM, Dave Hansen wrote:
> It does not revert cleanly because of the hunks below.  The code in
> those hunks was removed, so I tried running without properly merging
> them and it spews warnings because counter->usage is seen going negative.
> 
> So, it doesn't appear we can quickly revert this.

I'm fairly confident that I missed some of the cases (especially in the
charge-moving code), but the attached patch does at least work around
the regression for me.  It restores the original performance, or at
least gets _close_ to it.