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 were:

   - Add CONFIG_REFCOUNT_FULL=y to allow the disabling of the 'full'
     (robustness checked) refcount_t implementation with slightly lower
     runtime overhead. (Kees Cook)

     The lighter weight variant is the default. The two variants use the
     same API. Having this variant was a precondition by some
     maintainers to merge refcount_t cleanups.

   - Add lockdep support for rtmutexes (Peter Zijlstra)

   - liblockdep fixes and improvements (Sasha Levin, Ben Hutchings)

   - ... misc fixes and improvements"

* 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (30 commits)
  locking/refcount: Remove the half-implemented refcount_sub() API
  locking/refcount: Create unchecked atomic_t implementation
  locking/rtmutex: Don't initialize lockdep when not required
  locking/selftest: Add RT-mutex support
  locking/selftest: Remove the bad unlock ordering test
  rt_mutex: Add lockdep annotations
  MAINTAINERS: Claim atomic*_t maintainership
  locking/x86: Remove the unused atomic_inc_short() methd
  tools/lib/lockdep: Remove private kernel headers
  tools/lib/lockdep: Hide liblockdep output from test results
  tools/lib/lockdep: Add dummy current_gfp_context()
  tools/include: Add IS_ERR_OR_NULL to err.h
  tools/lib/lockdep: Add empty __is_[module,kernel]_percpu_address
  tools/lib/lockdep: Include err.h
  tools/include: Add (mostly) empty include/linux/sched/mm.h
  tools/lib/lockdep: Use LDFLAGS
  tools/lib/lockdep: Remove double-quotes from soname
  tools/lib/lockdep: Fix object file paths used in an out-of-tree build
  tools/lib/lockdep: Fix compilation for 4.11
  tools/lib/lockdep: Don't mix fd-based and stream IO
  ...

4 files changed, 122 insertions, 28 deletions

diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index a7a751a75cfd..9c5d40a50930 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -1052,6 +1052,7 @@ config DEBUG_LOCK_ALLOC
 	depends on DEBUG_KERNEL && TRACE_IRQFLAGS_SUPPORT && STACKTRACE_SUPPORT && LOCKDEP_SUPPORT
 	select DEBUG_SPINLOCK
 	select DEBUG_MUTEXES
+	select DEBUG_RT_MUTEXES if RT_MUTEXES
 	select LOCKDEP
 	help
 	 This feature will check whether any held lock (spinlock, rwlock,
@@ -1067,6 +1068,7 @@ config PROVE_LOCKING
 	select LOCKDEP
 	select DEBUG_SPINLOCK
 	select DEBUG_MUTEXES
+	select DEBUG_RT_MUTEXES if RT_MUTEXES
 	select DEBUG_LOCK_ALLOC
 	select TRACE_IRQFLAGS
 	default n
@@ -1121,6 +1123,7 @@ config LOCK_STAT
 	select LOCKDEP
 	select DEBUG_SPINLOCK
 	select DEBUG_MUTEXES
+	select DEBUG_RT_MUTEXES if RT_MUTEXES
 	select DEBUG_LOCK_ALLOC
 	default n
 	help
diff --git a/lib/locking-selftest-rtmutex.h b/lib/locking-selftest-rtmutex.h
new file mode 100644
index 000000000000..e3cb83989d16
--- /dev/null
+++ b/lib/locking-selftest-rtmutex.h
@@ -0,0 +1,11 @@
+#undef LOCK
+#define LOCK		RTL
+
+#undef UNLOCK
+#define UNLOCK		RTU
+
+#undef RLOCK
+#undef WLOCK
+
+#undef INIT
+#define INIT		RTI
diff --git a/lib/locking-selftest.c b/lib/locking-selftest.c
index f3a217ea0388..6f2b135dc5e8 100644
--- a/lib/locking-selftest.c
+++ b/lib/locking-selftest.c
@@ -21,6 +21,7 @@
 #include <linux/interrupt.h>
 #include <linux/debug_locks.h>
 #include <linux/irqflags.h>
+#include <linux/rtmutex.h>
 
 /*
  * Change this to 1 if you want to see the failure printouts:
@@ -46,6 +47,7 @@ __setup("debug_locks_verbose=", setup_debug_locks_verbose);
 #define LOCKTYPE_MUTEX	0x4
 #define LOCKTYPE_RWSEM	0x8
 #define LOCKTYPE_WW	0x10
+#define LOCKTYPE_RTMUTEX 0x20
 
 static struct ww_acquire_ctx t, t2;
 static struct ww_mutex o, o2, o3;
@@ -74,6 +76,15 @@ static DECLARE_RWSEM(rwsem_B);
 static DECLARE_RWSEM(rwsem_C);
 static DECLARE_RWSEM(rwsem_D);
 
+#ifdef CONFIG_RT_MUTEXES
+
+static DEFINE_RT_MUTEX(rtmutex_A);
+static DEFINE_RT_MUTEX(rtmutex_B);
+static DEFINE_RT_MUTEX(rtmutex_C);
+static DEFINE_RT_MUTEX(rtmutex_D);
+
+#endif
+
 /*
  * Locks that we initialize dynamically as well so that
  * e.g. X1 and X2 becomes two instances of the same class,
@@ -108,6 +119,17 @@ static DECLARE_RWSEM(rwsem_Y2);
 static DECLARE_RWSEM(rwsem_Z1);
 static DECLARE_RWSEM(rwsem_Z2);
 
+#ifdef CONFIG_RT_MUTEXES
+
+static DEFINE_RT_MUTEX(rtmutex_X1);
+static DEFINE_RT_MUTEX(rtmutex_X2);
+static DEFINE_RT_MUTEX(rtmutex_Y1);
+static DEFINE_RT_MUTEX(rtmutex_Y2);
+static DEFINE_RT_MUTEX(rtmutex_Z1);
+static DEFINE_RT_MUTEX(rtmutex_Z2);
+
+#endif
+
 /*
  * non-inlined runtime initializers, to let separate locks share
  * the same lock-class:
@@ -129,6 +151,17 @@ INIT_CLASS_FUNC(Z)
 
 static void init_shared_classes(void)
 {
+#ifdef CONFIG_RT_MUTEXES
+	static struct lock_class_key rt_X, rt_Y, rt_Z;
+
+	__rt_mutex_init(&rtmutex_X1, __func__, &rt_X);
+	__rt_mutex_init(&rtmutex_X2, __func__, &rt_X);
+	__rt_mutex_init(&rtmutex_Y1, __func__, &rt_Y);
+	__rt_mutex_init(&rtmutex_Y2, __func__, &rt_Y);
+	__rt_mutex_init(&rtmutex_Z1, __func__, &rt_Z);
+	__rt_mutex_init(&rtmutex_Z2, __func__, &rt_Z);
+#endif
+
 	init_class_X(&lock_X1, &rwlock_X1, &mutex_X1, &rwsem_X1);
 	init_class_X(&lock_X2, &rwlock_X2, &mutex_X2, &rwsem_X2);
 
@@ -193,6 +226,10 @@ static void init_shared_classes(void)
 #define MU(x)			mutex_unlock(&mutex_##x)
 #define MI(x)			mutex_init(&mutex_##x)
 
+#define RTL(x)			rt_mutex_lock(&rtmutex_##x)
+#define RTU(x)			rt_mutex_unlock(&rtmutex_##x)
+#define RTI(x)			rt_mutex_init(&rtmutex_##x)
+
 #define WSL(x)			down_write(&rwsem_##x)
 #define WSU(x)			up_write(&rwsem_##x)
 
@@ -264,6 +301,11 @@ GENERATE_TESTCASE(AA_wsem)
 #include "locking-selftest-rsem.h"
 GENERATE_TESTCASE(AA_rsem)
 
+#ifdef CONFIG_RT_MUTEXES
+#include "locking-selftest-rtmutex.h"
+GENERATE_TESTCASE(AA_rtmutex);
+#endif
+
 #undef E
 
 /*
@@ -345,6 +387,11 @@ GENERATE_TESTCASE(ABBA_wsem)
 #include "locking-selftest-rsem.h"
 GENERATE_TESTCASE(ABBA_rsem)
 
+#ifdef CONFIG_RT_MUTEXES
+#include "locking-selftest-rtmutex.h"
+GENERATE_TESTCASE(ABBA_rtmutex);
+#endif
+
 #undef E
 
 /*
@@ -373,6 +420,11 @@ GENERATE_TESTCASE(ABBCCA_wsem)
 #include "locking-selftest-rsem.h"
 GENERATE_TESTCASE(ABBCCA_rsem)
 
+#ifdef CONFIG_RT_MUTEXES
+#include "locking-selftest-rtmutex.h"
+GENERATE_TESTCASE(ABBCCA_rtmutex);
+#endif
+
 #undef E
 
 /*
@@ -401,6 +453,11 @@ GENERATE_TESTCASE(ABCABC_wsem)
 #include "locking-selftest-rsem.h"
 GENERATE_TESTCASE(ABCABC_rsem)
 
+#ifdef CONFIG_RT_MUTEXES
+#include "locking-selftest-rtmutex.h"
+GENERATE_TESTCASE(ABCABC_rtmutex);
+#endif
+
 #undef E
 
 /*
@@ -430,6 +487,11 @@ GENERATE_TESTCASE(ABBCCDDA_wsem)
 #include "locking-selftest-rsem.h"
 GENERATE_TESTCASE(ABBCCDDA_rsem)
 
+#ifdef CONFIG_RT_MUTEXES
+#include "locking-selftest-rtmutex.h"
+GENERATE_TESTCASE(ABBCCDDA_rtmutex);
+#endif
+
 #undef E
 
 /*
@@ -458,6 +520,11 @@ GENERATE_TESTCASE(ABCDBDDA_wsem)
 #include "locking-selftest-rsem.h"
 GENERATE_TESTCASE(ABCDBDDA_rsem)
 
+#ifdef CONFIG_RT_MUTEXES
+#include "locking-selftest-rtmutex.h"
+GENERATE_TESTCASE(ABCDBDDA_rtmutex);
+#endif
+
 #undef E
 
 /*
@@ -486,6 +553,11 @@ GENERATE_TESTCASE(ABCDBCDA_wsem)
 #include "locking-selftest-rsem.h"
 GENERATE_TESTCASE(ABCDBCDA_rsem)
 
+#ifdef CONFIG_RT_MUTEXES
+#include "locking-selftest-rtmutex.h"
+GENERATE_TESTCASE(ABCDBCDA_rtmutex);
+#endif
+
 #undef E
 
 /*
@@ -513,33 +585,10 @@ GENERATE_TESTCASE(double_unlock_wsem)
 #include "locking-selftest-rsem.h"
 GENERATE_TESTCASE(double_unlock_rsem)
 
-#undef E
-
-/*
- * Bad unlock ordering:
- */
-#define E()					\
-						\
-	LOCK(A);				\
-	LOCK(B);				\
-	UNLOCK(A); /* fail */			\
-	UNLOCK(B);
-
-/*
- * 6 testcases:
- */
-#include "locking-selftest-spin.h"
-GENERATE_TESTCASE(bad_unlock_order_spin)
-#include "locking-selftest-wlock.h"
-GENERATE_TESTCASE(bad_unlock_order_wlock)
-#include "locking-selftest-rlock.h"
-GENERATE_TESTCASE(bad_unlock_order_rlock)
-#include "locking-selftest-mutex.h"
-GENERATE_TESTCASE(bad_unlock_order_mutex)
-#include "locking-selftest-wsem.h"
-GENERATE_TESTCASE(bad_unlock_order_wsem)
-#include "locking-selftest-rsem.h"
-GENERATE_TESTCASE(bad_unlock_order_rsem)
+#ifdef CONFIG_RT_MUTEXES
+#include "locking-selftest-rtmutex.h"
+GENERATE_TESTCASE(double_unlock_rtmutex);
+#endif
 
 #undef E
 
@@ -567,6 +616,11 @@ GENERATE_TESTCASE(init_held_wsem)
 #include "locking-selftest-rsem.h"
 GENERATE_TESTCASE(init_held_rsem)
 
+#ifdef CONFIG_RT_MUTEXES
+#include "locking-selftest-rtmutex.h"
+GENERATE_TESTCASE(init_held_rtmutex);
+#endif
+
 #undef E
 
 /*
@@ -916,6 +970,9 @@ GENERATE_PERMUTATIONS_3_EVENTS(irq_read_recursion_soft)
 # define I_MUTEX(x)	lockdep_reset_lock(&mutex_##x.dep_map)
 # define I_RWSEM(x)	lockdep_reset_lock(&rwsem_##x.dep_map)
 # define I_WW(x)	lockdep_reset_lock(&x.dep_map)
+#ifdef CONFIG_RT_MUTEXES
+# define I_RTMUTEX(x)	lockdep_reset_lock(&rtmutex_##x.dep_map)
+#endif
 #else
 # define I_SPINLOCK(x)
 # define I_RWLOCK(x)
@@ -924,12 +981,23 @@ GENERATE_PERMUTATIONS_3_EVENTS(irq_read_recursion_soft)
 # define I_WW(x)
 #endif
 
+#ifndef I_RTMUTEX
+# define I_RTMUTEX(x)
+#endif
+
+#ifdef CONFIG_RT_MUTEXES
+#define I2_RTMUTEX(x)	rt_mutex_init(&rtmutex_##x)
+#else
+#define I2_RTMUTEX(x)
+#endif
+
 #define I1(x)					\
 	do {					\
 		I_SPINLOCK(x);			\
 		I_RWLOCK(x);			\
 		I_MUTEX(x);			\
 		I_RWSEM(x);			\
+		I_RTMUTEX(x);			\
 	} while (0)
 
 #define I2(x)					\
@@ -938,6 +1006,7 @@ GENERATE_PERMUTATIONS_3_EVENTS(irq_read_recursion_soft)
 		rwlock_init(&rwlock_##x);	\
 		mutex_init(&mutex_##x);		\
 		init_rwsem(&rwsem_##x);		\
+		I2_RTMUTEX(x);			\
 	} while (0)
 
 static void reset_locks(void)
@@ -1013,6 +1082,12 @@ static void dotest(void (*testcase_fn)(void), int expected, int lockclass_mask)
 	reset_locks();
 }
 
+#ifdef CONFIG_RT_MUTEXES
+#define dotest_rt(fn, e, m)	dotest((fn), (e), (m))
+#else
+#define dotest_rt(fn, e, m)
+#endif
+
 static inline void print_testname(const char *testname)
 {
 	printk("%33s:", testname);
@@ -1050,6 +1125,7 @@ static inline void print_testname(const char *testname)
 	dotest(name##_mutex, FAILURE, LOCKTYPE_MUTEX);		\
 	dotest(name##_wsem, FAILURE, LOCKTYPE_RWSEM);		\
 	dotest(name##_rsem, FAILURE, LOCKTYPE_RWSEM);		\
+	dotest_rt(name##_rtmutex, FAILURE, LOCKTYPE_RTMUTEX);	\
 	pr_cont("\n");
 
 #define DO_TESTCASE_6_SUCCESS(desc, name)			\
@@ -1060,6 +1136,7 @@ static inline void print_testname(const char *testname)
 	dotest(name##_mutex, SUCCESS, LOCKTYPE_MUTEX);		\
 	dotest(name##_wsem, SUCCESS, LOCKTYPE_RWSEM);		\
 	dotest(name##_rsem, SUCCESS, LOCKTYPE_RWSEM);		\
+	dotest_rt(name##_rtmutex, SUCCESS, LOCKTYPE_RTMUTEX);	\
 	pr_cont("\n");
 
 /*
@@ -1073,6 +1150,7 @@ static inline void print_testname(const char *testname)
 	dotest(name##_mutex, FAILURE, LOCKTYPE_MUTEX);		\
 	dotest(name##_wsem, FAILURE, LOCKTYPE_RWSEM);		\
 	dotest(name##_rsem, FAILURE, LOCKTYPE_RWSEM);		\
+	dotest_rt(name##_rtmutex, FAILURE, LOCKTYPE_RTMUTEX);	\
 	pr_cont("\n");
 
 #define DO_TESTCASE_2I(desc, name, nr)				\
@@ -1825,7 +1903,6 @@ void locking_selftest(void)
 	DO_TESTCASE_6R("A-B-C-D-B-C-D-A deadlock", ABCDBCDA);
 	DO_TESTCASE_6("double unlock", double_unlock);
 	DO_TESTCASE_6("initialize held", init_held);
-	DO_TESTCASE_6_SUCCESS("bad unlock order", bad_unlock_order);
 
 	printk("  --------------------------------------------------------------------------\n");
 	print_testname("recursive read-lock");
diff --git a/lib/refcount.c b/lib/refcount.c
index 9f906783987e..5d0582a9480c 100644
--- a/lib/refcount.c
+++ b/lib/refcount.c
@@ -37,6 +37,8 @@
 #include <linux/refcount.h>
 #include <linux/bug.h>
 
+#ifdef CONFIG_REFCOUNT_FULL
+
 /**
  * refcount_add_not_zero - add a value to a refcount unless it is 0
  * @i: the value to add to the refcount
@@ -225,6 +227,7 @@ void refcount_dec(refcount_t *r)
 	WARN_ONCE(refcount_dec_and_test(r), "refcount_t: decrement hit 0; leaking memory.\n");
 }
 EXPORT_SYMBOL(refcount_dec);
+#endif /* CONFIG_REFCOUNT_FULL */
 
 /**
  * refcount_dec_if_one - decrement a refcount if it is 1