From 4ea2176dfa714882e88180b474e4cbcd888b70af Mon Sep 17 00:00:00 2001 From: Ingo Molnar Date: Mon, 3 Jul 2006 00:24:53 -0700 Subject: [PATCH] lockdep: prove rwsem locking correctness Use the lock validator framework to prove rwsem locking correctness. Signed-off-by: Ingo Molnar Signed-off-by: Arjan van de Ven Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/asm-i386/rwsem.h | 35 +++++++++++++++++++++++++++-------- 1 file changed, 27 insertions(+), 8 deletions(-) (limited to 'include/asm-i386') diff --git a/include/asm-i386/rwsem.h b/include/asm-i386/rwsem.h index 558804e4a03..2f07601562e 100644 --- a/include/asm-i386/rwsem.h +++ b/include/asm-i386/rwsem.h @@ -40,6 +40,7 @@ #include #include +#include struct rwsem_waiter; @@ -61,21 +62,34 @@ struct rw_semaphore { #define RWSEM_ACTIVE_WRITE_BIAS (RWSEM_WAITING_BIAS + RWSEM_ACTIVE_BIAS) spinlock_t wait_lock; struct list_head wait_list; +#ifdef CONFIG_DEBUG_LOCK_ALLOC + struct lockdep_map dep_map; +#endif }; +#ifdef CONFIG_DEBUG_LOCK_ALLOC +# define __RWSEM_DEP_MAP_INIT(lockname) , .dep_map = { .name = #lockname } +#else +# define __RWSEM_DEP_MAP_INIT(lockname) +#endif + + #define __RWSEM_INITIALIZER(name) \ { RWSEM_UNLOCKED_VALUE, SPIN_LOCK_UNLOCKED, LIST_HEAD_INIT((name).wait_list) \ - } + __RWSEM_DEP_MAP_INIT(name) } #define DECLARE_RWSEM(name) \ struct rw_semaphore name = __RWSEM_INITIALIZER(name) -static inline void init_rwsem(struct rw_semaphore *sem) -{ - sem->count = RWSEM_UNLOCKED_VALUE; - spin_lock_init(&sem->wait_lock); - INIT_LIST_HEAD(&sem->wait_list); -} +extern void __init_rwsem(struct rw_semaphore *sem, const char *name, + struct lock_class_key *key); + +#define init_rwsem(sem) \ +do { \ + static struct lock_class_key __key; \ + \ + __init_rwsem((sem), #sem, &__key); \ +} while (0) /* * lock for reading @@ -128,7 +142,7 @@ LOCK_PREFIX " cmpxchgl %2,%0\n\t" /* * lock for writing */ -static inline void __down_write(struct rw_semaphore *sem) +static inline void __down_write_nested(struct rw_semaphore *sem, int subclass) { int tmp; @@ -152,6 +166,11 @@ LOCK_PREFIX " xadd %%edx,(%%eax)\n\t" /* subtract 0x0000ffff, returns the : "memory", "cc"); } +static inline void __down_write(struct rw_semaphore *sem) +{ + __down_write_nested(sem, 0); +} + /* * trylock for writing -- returns 1 if successful, 0 if contention */ -- cgit v1.2.3-70-g09d2