Merge branch 'locking-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

* 'locking-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  spinlock: Add missing __raw_spin_lock_flags() stub for UP
  mutex: add atomic_dec_and_mutex_lock(), fix
  locking, rtmutex.c: Documentation cleanup
  mutex: add atomic_dec_and_mutex_lock()