locking/spinlock/rt: Prepare for RT local_lock

Add the static and runtime initializer mechanics to support the RT variant
of local_lock, which requires the lock type in the lockdep map to be set
to LD_LOCK_PERCPU.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20210815211305.967526724@linutronix.de

include/linux/spinlock_rt.h

@@ -8,10 +8,10 @@
 
 #ifdef CONFIG_DEBUG_LOCK_ALLOC
 extern void __rt_spin_lock_init(spinlock_t *lock, const char *name,
-				struct lock_class_key *key);
+				struct lock_class_key *key, bool percpu);
 #else
 static inline void __rt_spin_lock_init(spinlock_t *lock, const char *name,
-				       struct lock_class_key *key)
+				struct lock_class_key *key, bool percpu)
 {
 }
 #endif
@@ -21,7 +21,15 @@ do {							\
 	static struct lock_class_key __key;			\
 								\
 	rt_mutex_base_init(&(slock)->lock);			\
-	__rt_spin_lock_init(slock, #slock, &__key);	\
+	__rt_spin_lock_init(slock, #slock, &__key, false);	\
+} while (0)
+
+#define local_spin_lock_init(slock)				\
+do {								\
+	static struct lock_class_key __key;			\
+								\
+	rt_mutex_base_init(&(slock)->lock);			\
+	__rt_spin_lock_init(slock, #slock, &__key, true);	\
 } while (0)
 
 extern void rt_spin_lock(spinlock_t *lock);

include/linux/spinlock_types.h

@@ -60,6 +60,12 @@ typedef struct spinlock {
 		SPIN_DEP_MAP_INIT(name)				\
 	}
 
+#define __LOCAL_SPIN_LOCK_UNLOCKED(name)			\
+	{							\
+		.lock = __RT_MUTEX_BASE_INITIALIZER(name.lock),	\
+		LOCAL_SPIN_DEP_MAP_INIT(name)			\
+	}
+
 #define DEFINE_SPINLOCK(name)					\
 	spinlock_t name = __SPIN_LOCK_UNLOCKED(name)
 

include/linux/spinlock_types_raw.h

@@ -37,9 +37,17 @@ typedef struct raw_spinlock {
 		.name = #lockname,			\
 		.wait_type_inner = LD_WAIT_CONFIG,	\
 	}
+
+# define LOCAL_SPIN_DEP_MAP_INIT(lockname)		\
+	.dep_map = {					\
+		.name = #lockname,			\
+		.wait_type_inner = LD_WAIT_CONFIG,	\
+		.lock_type = LD_LOCK_PERCPU,		\
+	}
 #else
 # define RAW_SPIN_DEP_MAP_INIT(lockname)
 # define SPIN_DEP_MAP_INIT(lockname)
+# define LOCAL_SPIN_DEP_MAP_INIT(lockname)
 #endif
 
 #ifdef CONFIG_DEBUG_SPINLOCK

kernel/locking/spinlock_rt.c

@@ -120,10 +120,13 @@ EXPORT_SYMBOL(rt_spin_trylock_bh);
 
 #ifdef CONFIG_DEBUG_LOCK_ALLOC
 void __rt_spin_lock_init(spinlock_t *lock, const char *name,
-			 struct lock_class_key *key)
+			 struct lock_class_key *key, bool percpu)
 {
+	u8 type = percpu ? LD_LOCK_PERCPU : LD_LOCK_NORMAL;
+
 	debug_check_no_locks_freed((void *)lock, sizeof(*lock));
-	lockdep_init_map_wait(&lock->dep_map, name, key, 0, LD_WAIT_CONFIG);
+	lockdep_init_map_type(&lock->dep_map, name, key, 0, LD_WAIT_CONFIG,
+			      LD_WAIT_INV, type);
 }
 EXPORT_SYMBOL(__rt_spin_lock_init);
 #endif