[PATCH 0/2] performance regression in mark_edges_uninteresting

This series fixes a rev-list performance regression in fbd4a70 (list-objects: mark more commits as edges in mark_edges_uninteresting, 2013-08-16). That commit is a little tricky because it actually _knows_ it's trading off CPU for a better packfile, but I think we're performing the tradeoff in too many places. See the second commit for details.

  [1/2]: t/perf: time rev-list with UNINTERESTING commits
  [2/2]: list-objects: only look at cmdline trees with edge_hint

Here's t/perf/p0001 output that shows the problem:

  0001.5: rev-list --objects $commit --not --all
  fbd4a703^         fbd4a703                  HEAD
  0.04(0.04+0.00)   0.28(0.27+0.00) +600.0%   0.04(0.04+0.00) +0.0%

-Peff

PS If you are wondering about the output format above, I had to munge it manually to avoid giant 115-character lines. We should maybe teach the perf suite an alternate output format. :)