From 4dfbb9d8c6cbfc32faa5c71145bd2a43e1f8237c Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Wed, 11 Oct 2006 01:45:14 -0400 Subject: Lockdep: add lockdep_set_class_and_subclass() and lockdep_set_subclass() This annotation makes it possible to assign a subclass on lock init. This annotation is meant to reduce the _nested() annotations by assigning a default subclass. One could do without this annotation and rely on lockdep_set_class() exclusively, but that would require a manual stack of struct lock_class_key objects. Signed-off-by: Peter Zijlstra Signed-off-by: Dmitry Torokhov --- kernel/lockdep.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) (limited to 'kernel/lockdep.c') diff --git a/kernel/lockdep.c b/kernel/lockdep.c index 4c055346100..ba7156ac70c 100644 --- a/kernel/lockdep.c +++ b/kernel/lockdep.c @@ -1177,7 +1177,7 @@ look_up_lock_class(struct lockdep_map *lock, unsigned int subclass) * itself, so actual lookup of the hash should be once per lock object. */ static inline struct lock_class * -register_lock_class(struct lockdep_map *lock, unsigned int subclass) +register_lock_class(struct lockdep_map *lock, unsigned int subclass, int force) { struct lockdep_subclass_key *key; struct list_head *hash_head; @@ -1249,7 +1249,7 @@ register_lock_class(struct lockdep_map *lock, unsigned int subclass) out_unlock_set: __raw_spin_unlock(&hash_lock); - if (!subclass) + if (!subclass || force) lock->class_cache = class; DEBUG_LOCKS_WARN_ON(class->subclass != subclass); @@ -1937,7 +1937,7 @@ void trace_softirqs_off(unsigned long ip) * Initialize a lock instance's lock-class mapping info: */ void lockdep_init_map(struct lockdep_map *lock, const char *name, - struct lock_class_key *key) + struct lock_class_key *key, int subclass) { if (unlikely(!debug_locks)) return; @@ -1957,6 +1957,8 @@ void lockdep_init_map(struct lockdep_map *lock, const char *name, lock->name = name; lock->key = key; lock->class_cache = NULL; + if (subclass) + register_lock_class(lock, subclass, 1); } EXPORT_SYMBOL_GPL(lockdep_init_map); @@ -1995,7 +1997,7 @@ static int __lock_acquire(struct lockdep_map *lock, unsigned int subclass, * Not cached yet or subclass? */ if (unlikely(!class)) { - class = register_lock_class(lock, subclass); + class = register_lock_class(lock, subclass, 0); if (!class) return 0; } -- cgit v1.2.3-18-g5258