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

Pull locking fixes from Ingo Molnar:
 "No functional effects intended: removes leftovers from recent lockdep
  and refcounts work"

* 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  locking/refcounts: Remove stale comment from the ARCH_HAS_REFCOUNT Kconfig entry
  locking/lockdep: Remove cross-release leftovers
  locking/Documentation: Remove stale crossrelease_fullstack parameter

Documentation/admin-guide/kernel-parameters.txt

@@ -713,9 +713,6 @@
 			It will be ignored when crashkernel=X,high is not used
 			or memory reserved is below 4G.
 
-	crossrelease_fullstack
-			[KNL] Allow to record full stack trace in cross-release
-
 	cryptomgr.notests
                         [KNL] Disable crypto self-tests
 

arch/x86/Kconfig

@@ -55,7 +55,6 @@ config X86
 	select ARCH_HAS_GCOV_PROFILE_ALL
 	select ARCH_HAS_KCOV			if X86_64
 	select ARCH_HAS_PMEM_API		if X86_64
-	# Causing hangs/crashes, see the commit that added this change for details.
 	select ARCH_HAS_REFCOUNT
 	select ARCH_HAS_UACCESS_FLUSHCACHE	if X86_64
 	select ARCH_HAS_SET_MEMORY

include/linux/completion.h

@@ -32,7 +32,6 @@ struct completion {
 #define init_completion(x) __init_completion(x)
 static inline void complete_acquire(struct completion *x) {}
 static inline void complete_release(struct completion *x) {}
-static inline void complete_release_commit(struct completion *x) {}
 
 #define COMPLETION_INITIALIZER(work) \
 	{ 0, __WAIT_QUEUE_HEAD_INITIALIZER((work).wait) }

include/linux/irqflags.h

@@ -27,22 +27,18 @@
 # define trace_hardirq_enter()			\
 do {						\
 	current->hardirq_context++;		\
-	crossrelease_hist_start(XHLOCK_HARD);	\
 } while (0)
 # define trace_hardirq_exit()			\
 do {						\
 	current->hardirq_context--;		\
-	crossrelease_hist_end(XHLOCK_HARD);	\
 } while (0)
 # define lockdep_softirq_enter()		\
 do {						\
 	current->softirq_context++;		\
-	crossrelease_hist_start(XHLOCK_SOFT);	\
 } while (0)
 # define lockdep_softirq_exit()			\
 do {						\
 	current->softirq_context--;		\
-	crossrelease_hist_end(XHLOCK_SOFT);	\
 } while (0)
 # define INIT_TRACE_IRQFLAGS	.softirqs_enabled = 1,
 #else

include/linux/lockdep.h

@@ -475,8 +475,6 @@ enum xhlock_context_t {
 #define STATIC_LOCKDEP_MAP_INIT(_name, _key) \
 	{ .name = (_name), .key = (void *)(_key), }
 
-static inline void crossrelease_hist_start(enum xhlock_context_t c) {}
-static inline void crossrelease_hist_end(enum xhlock_context_t c) {}
 static inline void lockdep_invariant_state(bool force) {}
 static inline void lockdep_init_task(struct task_struct *task) {}
 static inline void lockdep_free_task(struct task_struct *task) {}

kernel/sched/completion.c

@@ -34,11 +34,6 @@ void complete(struct completion *x)
 
 	spin_lock_irqsave(&x->wait.lock, flags);
 
-	/*
-	 * Perform commit of crossrelease here.
-	 */
-	complete_release_commit(x);
-
 	if (x->done != UINT_MAX)
 		x->done++;
 	__wake_up_locked(&x->wait, TASK_NORMAL, 1);