[PATCH/RFC v2 0/3] git checkout optimisation - part 3

Changes sine v1 (v1 was posted with subject "The ext4 filesystem and racy git")

-- patch 2/3 --
   Added missing timestamp => timestamp.(u)sec update for
   unpack-trees.c

-- patch 3/3 --
   New patch which removes some 14300 lstat(2) calls, and the total is
   now at 41677 calls, or 1.382 calls/unique string to lstat() for the
   reference 'git checkout'-test to Linux tag v2.6.27.

   Total reduction so far for all the lstat/git checkout optimisation
   patches has been 120954 - 41677 = 79277 calls.  Some 14400 fstat(2)
   calls is added, but those should be faster than simmilar lstat()
   calls.

(patch-series based on master)

Kjetil Barvik (3):
  fix compile error when USE_NSEC is defined
  make USE_NSEC work as expected
  verify_uptodate(): add ce_uptodate(ce) test

 builtin-fetch-pack.c |    4 +-
 cache.h              |    6 ++--
 read-cache.c         |   70 ++++++++++++++++++++++++++++++++++++++++----------
 unpack-trees.c       |   10 +++++--
 4 files changed, 68 insertions(+), 22 deletions(-)