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

Pull locking updates from Ingo Molnar:
 "The main changes in this cycle are:

   - big rtmutex and futex cleanup and robustification from Thomas
     Gleixner
   - mutex optimizations and refinements from Jason Low
   - arch_mutex_cpu_relax() removal and related cleanups
   - smaller lockdep tweaks"

* 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (23 commits)
  arch, locking: Ciao arch_mutex_cpu_relax()
  locking/lockdep: Only ask for /proc/lock_stat output when available
  locking/mutexes: Optimize mutex trylock slowpath
  locking/mutexes: Try to acquire mutex only if it is unlocked
  locking/mutexes: Delete the MUTEX_SHOW_NO_WAITER macro
  locking/mutexes: Correct documentation on mutex optimistic spinning
  rtmutex: Make the rtmutex tester depend on BROKEN
  futex: Simplify futex_lock_pi_atomic() and make it more robust
  futex: Split out the first waiter attachment from lookup_pi_state()
  futex: Split out the waiter check from lookup_pi_state()
  futex: Use futex_top_waiter() in lookup_pi_state()
  futex: Make unlock_pi more robust
  rtmutex: Avoid pointless requeueing in the deadlock detection chain walk
  rtmutex: Cleanup deadlock detector debug logic
  rtmutex: Confine deadlock logic to futex
  rtmutex: Simplify remove_waiter()
  rtmutex: Document pi chain walk
  rtmutex: Clarify the boost/deboost part
  rtmutex: No need to keep task ref for lock owner check
  rtmutex: Simplify and document try_to_take_rtmutex()
  ...

2 files changed, 2 insertions, 3 deletions

diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index 12132e433e30..901096d31c66 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -835,7 +835,7 @@ config DEBUG_RT_MUTEXES
 
 config RT_MUTEX_TESTER
         bool "Built-in scriptable tester for rt-mutexes"
-        depends on DEBUG_KERNEL && RT_MUTEXES
+        depends on DEBUG_KERNEL && RT_MUTEXES && BROKEN
         help
           This option enables a rt-mutex tester.
 
diff --git a/lib/lockref.c b/lib/lockref.c
index f07a40d33871..d2233de9a86e 100644
--- a/lib/lockref.c
+++ b/lib/lockref.c
@@ -1,6 +1,5 @@
 #include <linux/export.h>
 #include <linux/lockref.h>
-#include <linux/mutex.h>
 
 #if USE_CMPXCHG_LOCKREF
 
@@ -29,7 +28,7 @@
                 if (likely(old.lock_count == prev.lock_count)) {                \
                         SUCCESS;                                                \
                 }                                                               \
-                arch_mutex_cpu_relax();                                         \
+                cpu_relax_lowlatency();                                         \
         }                                                                       \
 } while (0)