[PATCH 2/6] locking/lockdep: Mark local_lock_t

[Peter Zijlstra]

The local_lock_t's are special, because they cannot form IRQ
inversions, make sure we can tell them apart from the rest of the
locks.

Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
---
 include/linux/local_lock_internal.h |    5 ++++-
 include/linux/lockdep.h             |   15 ++++++++++++---
 include/linux/lockdep_types.h       |   18 ++++++++++++++----
 kernel/locking/lockdep.c            |   16 +++++++++-------
 4 files changed, 39 insertions(+), 15 deletions(-)

--- a/include/linux/local_lock_internal.h
+++ b/include/linux/local_lock_internal.h
@@ -18,6 +18,7 @@ typedef struct {
 	.dep_map = {					\
 		.name = #lockname,			\
 		.wait_type_inner = LD_WAIT_CONFIG,	\
+		.lock_type = LD_LOCK_PERCPU,			\
 	}
 #else
 # define LL_DEP_MAP_INIT(lockname)
@@ -30,7 +31,9 @@ do {								\
 	static struct lock_class_key __key;			\
 								\
 	debug_check_no_locks_freed((void *)lock, sizeof(*lock));\
-	lockdep_init_map_wait(&(lock)->dep_map, #lock, &__key, 0, LD_WAIT_CONFIG);\
+	lockdep_init_map_type(&(lock)->dep_map, #lock, &__key, 0, \
+			      LD_WAIT_CONFIG, LD_WAIT_INV,	\
+			      LD_LOCK_PERCPU);			\
 } while (0)
 
 #ifdef CONFIG_DEBUG_LOCK_ALLOC
--- a/include/linux/lockdep.h
+++ b/include/linux/lockdep.h
@@ -185,12 +185,19 @@ extern void lockdep_unregister_key(struc
  * to lockdep:
  */
 
-extern void lockdep_init_map_waits(struct lockdep_map *lock, const char *name,
-	struct lock_class_key *key, int subclass, short inner, short outer);
+extern void lockdep_init_map_type(struct lockdep_map *lock, const char *name,
+	struct lock_class_key *key, int subclass, u8 inner, u8 outer, u8 lock_type);
+
+static inline void
+lockdep_init_map_waits(struct lockdep_map *lock, const char *name,
+		       struct lock_class_key *key, int subclass, u8 inner, u8 outer)
+{
+	lockdep_init_map_type(lock, name, key, subclass, inner, LD_WAIT_INV, LD_LOCK_NORMAL);
+}
 
 static inline void
 lockdep_init_map_wait(struct lockdep_map *lock, const char *name,
-		      struct lock_class_key *key, int subclass, short inner)
+		      struct lock_class_key *key, int subclass, u8 inner)
 {
 	lockdep_init_map_waits(lock, name, key, subclass, inner, LD_WAIT_INV);
 }
@@ -340,6 +347,8 @@ static inline void lockdep_set_selftest_
 # define lock_set_class(l, n, k, s, i)		do { } while (0)
 # define lock_set_subclass(l, s, i)		do { } while (0)
 # define lockdep_init()				do { } while (0)
+# define lockdep_init_map_type(lock, name, key, sub, inner, outer) \
+		do { (void)(name); (void)(key); } while (0)
 # define lockdep_init_map_waits(lock, name, key, sub, inner, outer) \
 		do { (void)(name); (void)(key); } while (0)
 # define lockdep_init_map_wait(lock, name, key, sub, inner) \
--- a/include/linux/lockdep_types.h
+++ b/include/linux/lockdep_types.h
@@ -30,6 +30,12 @@ enum lockdep_wait_type {
 	LD_WAIT_MAX,		/* must be last */
 };
 
+enum lockdep_lock_type {
+	LD_LOCK_NORMAL = 0,	/* normal, catch all */
+	LD_LOCK_PERCPU,		/* percpu */
+	LD_LOCK_MAX,
+};
+
 #ifdef CONFIG_LOCKDEP
 
 /*
@@ -119,8 +125,10 @@ struct lock_class {
 	int				name_version;
 	const char			*name;
 
-	short				wait_type_inner;
-	short				wait_type_outer;
+	u8				wait_type_inner;
+	u8				wait_type_outer;
+	u8				lock_type;
+	/* u8				hole; */
 
 #ifdef CONFIG_LOCK_STAT
 	unsigned long			contention_point[LOCKSTAT_POINTS];
@@ -169,8 +177,10 @@ struct lockdep_map {
 	struct lock_class_key		*key;
 	struct lock_class		*class_cache[NR_LOCKDEP_CACHING_CLASSES];
 	const char			*name;
-	short				wait_type_outer; /* can be taken in this context */
-	short				wait_type_inner; /* presents this context */
+	u8				wait_type_outer; /* can be taken in this context */
+	u8				wait_type_inner; /* presents this context */
+	u8				lock_type;
+	/* u8				hole; */
 #ifdef CONFIG_LOCK_STAT
 	int				cpu;
 	unsigned long			ip;
--- a/kernel/locking/lockdep.c
+++ b/kernel/locking/lockdep.c
@@ -1290,6 +1290,7 @@ register_lock_class(struct lockdep_map *
 	class->name_version = count_matching_names(class);
 	class->wait_type_inner = lock->wait_type_inner;
 	class->wait_type_outer = lock->wait_type_outer;
+	class->lock_type = lock->lock_type;
 	/*
 	 * We use RCU's safe list-add method to make
 	 * parallel walking of the hash-list safe:
@@ -4503,9 +4504,9 @@ print_lock_invalid_wait_context(struct t
  */
 static int check_wait_context(struct task_struct *curr, struct held_lock *next)
 {
-	short next_inner = hlock_class(next)->wait_type_inner;
-	short next_outer = hlock_class(next)->wait_type_outer;
-	short curr_inner;
+	u8 next_inner = hlock_class(next)->wait_type_inner;
+	u8 next_outer = hlock_class(next)->wait_type_outer;
+	u8 curr_inner;
 	int depth;
 
 	if (!next_inner || next->trylock)
@@ -4532,7 +4533,7 @@ static int check_wait_context(struct tas
 
 	for (; depth < curr->lockdep_depth; depth++) {
 		struct held_lock *prev = curr->held_locks + depth;
-		short prev_inner = hlock_class(prev)->wait_type_inner;
+		u8 prev_inner = hlock_class(prev)->wait_type_inner;
 
 		if (prev_inner) {
 			/*
@@ -4581,9 +4582,9 @@ static inline int check_wait_context(str
 /*
  * Initialize a lock instance's lock-class mapping info:
  */
-void lockdep_init_map_waits(struct lockdep_map *lock, const char *name,
+void lockdep_init_map_type(struct lockdep_map *lock, const char *name,
 			    struct lock_class_key *key, int subclass,
-			    short inner, short outer)
+			    u8 inner, u8 outer, u8 lock_type)
 {
 	int i;
 
@@ -4606,6 +4607,7 @@ void lockdep_init_map_waits(struct lockd
 
 	lock->wait_type_outer = outer;
 	lock->wait_type_inner = inner;
+	lock->lock_type = lock_type;
 
 	/*
 	 * No key, no joy, we need to hash something.
@@ -4640,7 +4642,7 @@ void lockdep_init_map_waits(struct lockd
 		raw_local_irq_restore(flags);
 	}
 }
-EXPORT_SYMBOL_GPL(lockdep_init_map_waits);
+EXPORT_SYMBOL_GPL(lockdep_init_map_type);
 
 struct lock_class_key __lockdep_no_validate__;
 EXPORT_SYMBOL_GPL(__lockdep_no_validate__);