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

Pull core locking updates from Ingo Molnar:
 "The biggest change is the MCS spinlock generalization changes from Tim
  Chen, Peter Zijlstra, Jason Low et al.  There's also lockdep
  fixes/enhancements from Oleg Nesterov, in particular a false negative
  fix related to lockdep_set_novalidate_class() usage"

* 'core-locking-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (22 commits)
  locking/mutex: Fix debug checks
  locking/mutexes: Add extra reschedule point
  locking/mutexes: Introduce cancelable MCS lock for adaptive spinning
  locking/mutexes: Unlock the mutex without the wait_lock
  locking/mutexes: Modify the way optimistic spinners are queued
  locking/mutexes: Return false if task need_resched() in mutex_can_spin_on_owner()
  locking: Move mcs_spinlock.h into kernel/locking/
  m68k: Skip futex_atomic_cmpxchg_inatomic() test
  futex: Allow architectures to skip futex_atomic_cmpxchg_inatomic() test
  Revert "sched/wait: Suppress Sparse 'variable shadowing' warning"
  lockdep: Change lockdep_set_novalidate_class() to use _and_name
  lockdep: Change mark_held_locks() to check hlock->check instead of lockdep_no_validate
  lockdep: Don't create the wrong dependency on hlock->check == 0
  lockdep: Make held_lock->check and "int check" argument bool
  locking/mcs: Allow architecture specific asm files to be used for contended case
  locking/mcs: Order the header files in Kbuild of each architecture in alphabetical order
  sched/wait: Suppress Sparse 'variable shadowing' warning
  hung_task/Documentation: Fix hung_task_warnings description
  locking/mcs: Allow architectures to hook in to contended paths
  locking/mcs: Micro-optimize the MCS code, add extra comments
  ...

diff --cc arch/avr32/include/asm/Kbuild
index c7c64a63c29f470ebbec5071422d148ba9bc074a,8b398ff96974f339d7443122459de08f81caad8e..00a0f3ccd6eb994a67071d8e544762475f1ca792
--- 1/arch/avr32/include/asm/Kbuild
--- 2/arch/avr32/include/asm/Kbuild
+++ b/arch/avr32/include/asm/Kbuild
@@@ -1,22 -1,22 +1,23 @@@
  
- generic-y     += clkdev.h
- generic-y       += cputime.h
- generic-y       += delay.h
- generic-y       += device.h
- generic-y       += div64.h
- generic-y       += emergency-restart.h
- generic-y     += exec.h
- generic-y       += futex.h
- generic-y     += preempt.h
- generic-y       += irq_regs.h
- generic-y     += param.h
- generic-y       += local.h
- generic-y       += local64.h
- generic-y       += percpu.h
- generic-y       += scatterlist.h
- generic-y       += sections.h
- generic-y       += topology.h
- generic-y     += trace_clock.h
+ generic-y += clkdev.h
+ generic-y += cputime.h
+ generic-y += delay.h
+ generic-y += device.h
+ generic-y += div64.h
+ generic-y += emergency-restart.h
+ generic-y += exec.h
+ generic-y += futex.h
+ generic-y += hash.h
+ generic-y += irq_regs.h
+ generic-y += local.h
+ generic-y += local64.h
+ generic-y += mcs_spinlock.h
+ generic-y += param.h
+ generic-y += percpu.h
+ generic-y += preempt.h
+ generic-y += scatterlist.h
+ generic-y += sections.h
+ generic-y += topology.h
+ generic-y += trace_clock.h
 +generic-y += vga.h
- generic-y       += xor.h
- generic-y     += hash.h
+ generic-y += xor.h

diff --cc arch/m68k/include/asm/Kbuild
Simple merge

diff --cc kernel/futex.c
index 08ec814ad9d2fe95ae4303085cb1967265bd3758,5d17e3a83f8c39ad021c8ed4550593766bce6806..67dacaf93e56c0edb12b74a84b40da9fe596ea49
--- 1/kernel/futex.c
--- 2/kernel/futex.c
+++ b/kernel/futex.c
@@@ -2893,21 -2882,10 +2914,11 @@@ static int __init futex_init(void
                                               &futex_shift, NULL,
                                               futex_hashsize, futex_hashsize);
        futex_hashsize = 1UL << futex_shift;
-       /*
-        * This will fail and we want it. Some arch implementations do
-        * runtime detection of the futex_atomic_cmpxchg_inatomic()
-        * functionality. We want to know that before we call in any
-        * of the complex code paths. Also we want to prevent
-        * registration of robust lists in that case. NULL is
-        * guaranteed to fault and we get -EFAULT on functional
-        * implementation, the non-functional ones will return
-        * -ENOSYS.
-        */
-       if (cmpxchg_futex_value_locked(&curval, NULL, 0, 0) == -EFAULT)
-               futex_cmpxchg_enabled = 1;
+ 
+       futex_detect_cmpxchg();
  
        for (i = 0; i < futex_hashsize; i++) {
 +              atomic_set(&futex_queues[i].waiters, 0);
                plist_head_init(&futex_queues[i].chain);
                spin_lock_init(&futex_queues[i].lock);
        }