diff options
| -rw-r--r-- | include/asm-i386/rwsem.h | 35 | ||||
| -rw-r--r-- | include/asm-s390/rwsem.h | 31 | ||||
| -rw-r--r-- | include/asm-s390/semaphore.h | 3 | ||||
| -rw-r--r-- | include/linux/rwsem-spinlock.h | 23 | ||||
| -rw-r--r-- | include/linux/rwsem.h | 59 | ||||
| -rw-r--r-- | kernel/Makefile | 2 | ||||
| -rw-r--r-- | kernel/rwsem.c | 42 | ||||
| -rw-r--r-- | lib/rwsem-spinlock.c | 20 | ||||
| -rw-r--r-- | lib/rwsem.c | 20 |
9 files changed, 184 insertions, 51 deletions
diff --git a/include/asm-i386/rwsem.h b/include/asm-i386/rwsem.h index 558804e..2f07601 100644 --- a/include/asm-i386/rwsem.h +++ b/include/asm-i386/rwsem.h @@ -40,6 +40,7 @@ #include <linux/list.h> #include <linux/spinlock.h> +#include <linux/lockdep.h> 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 */ diff --git a/include/asm-s390/rwsem.h b/include/asm-s390/rwsem.h index 0422a08..13ec169 100644 --- a/include/asm-s390/rwsem.h +++ b/include/asm-s390/rwsem.h @@ -61,6 +61,9 @@ struct rw_semaphore { signed long count; spinlock_t wait_lock; struct list_head wait_list; +#ifdef CONFIG_DEBUG_LOCK_ALLOC + struct lockdep_map dep_map; +#endif }; #ifndef __s390x__ @@ -80,8 +83,16 @@ struct rw_semaphore { /* * initialisation */ + +#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_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) @@ -93,6 +104,17 @@ static inline void init_rwsem(struct rw_semaphore *sem) 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 */ @@ -155,7 +177,7 @@ static inline int __down_read_trylock(struct rw_semaphore *sem) /* * lock for writing */ -static inline void __down_write(struct rw_semaphore *sem) +static inline void __down_write_nested(struct rw_semaphore *sem, int subclass) { signed long old, new, tmp; @@ -181,6 +203,11 @@ static inline void __down_write(struct rw_semaphore *sem) rwsem_down_write_failed(sem); } +static inline void __down_write(struct rw_semaphore *sem) +{ + __down_write_nested(sem, 0); +} + /* * trylock for writing -- returns 1 if successful, 0 if contention */ diff --git a/include/asm-s390/semaphore.h b/include/asm-s390/semaphore.h index 702cf43..32cdc69 100644 --- a/include/asm-s390/semaphore.h +++ b/include/asm-s390/semaphore.h @@ -37,7 +37,8 @@ struct semaphore { static inline void sema_init (struct semaphore *sem, int val) { - *sem = (struct semaphore) __SEMAPHORE_INITIALIZER((*sem),val); + atomic_set(&sem->count, val); + init_waitqueue_head(&sem->wait); } static inline void init_MUTEX (struct semaphore *sem) diff --git a/include/linux/rwsem-spinlock.h b/include/linux/rwsem-spinlock.h index d68afcc..ae1fcad 100644 --- a/include/linux/rwsem-spinlock.h +++ b/include/linux/rwsem-spinlock.h @@ -32,18 +32,37 @@ struct rw_semaphore { __s32 activity; 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) \ -{ 0, SPIN_LOCK_UNLOCKED, LIST_HEAD_INIT((name).wait_list) } +{ 0, 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) -extern void FASTCALL(init_rwsem(struct rw_semaphore *sem)); +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) + extern void FASTCALL(__down_read(struct rw_semaphore *sem)); extern int FASTCALL(__down_read_trylock(struct rw_semaphore *sem)); extern void FASTCALL(__down_write(struct rw_semaphore *sem)); +extern void FASTCALL(__down_write_nested(struct rw_semaphore *sem, int subclass)); extern int FASTCALL(__down_write_trylock(struct rw_semaphore *sem)); extern void FASTCALL(__up_read(struct rw_semaphore *sem)); extern void FASTCALL(__up_write(struct rw_semaphore *sem)); diff --git a/include/linux/rwsem.h b/include/linux/rwsem.h index 9358153..658afb3 100644 --- a/include/linux/rwsem.h +++ b/include/linux/rwsem.h @@ -27,64 +27,55 @@ struct rw_semaphore; /* * lock for reading */ -static inline void down_read(struct rw_semaphore *sem) -{ - might_sleep(); - __down_read(sem); -} +extern void down_read(struct rw_semaphore *sem); /* * trylock for reading -- returns 1 if successful, 0 if contention */ -static inline int down_read_trylock(struct rw_semaphore *sem) -{ - int ret; - ret = __down_read_trylock(sem); - return ret; -} +extern int down_read_trylock(struct rw_semaphore *sem); /* * lock for writing */ -static inline void down_write(struct rw_semaphore *sem) -{ - might_sleep(); - __down_write(sem); -} +extern void down_write(struct rw_semaphore *sem); /* * trylock for writing -- returns 1 if successful, 0 if contention */ -static inline int down_write_trylock(struct rw_semaphore *sem) -{ - int ret; - ret = __down_write_trylock(sem); - return ret; -} +extern int down_write_trylock(struct rw_semaphore *sem); /* * release a read lock */ -static inline void up_read(struct rw_semaphore *sem) -{ - __up_read(sem); -} +extern void up_read(struct rw_semaphore *sem); /* * release a write lock */ -static inline void up_write(struct rw_semaphore *sem) -{ - __up_write(sem); -} +extern void up_write(struct rw_semaphore *sem); /* * downgrade write lock to read lock */ -static inline void downgrade_write(struct rw_semaphore *sem) -{ - __downgrade_write(sem); -} +extern void downgrade_write(struct rw_semaphore *sem); + +#ifdef CONFIG_DEBUG_LOCK_ALLOC +/* + * nested locking: + */ +extern void down_read_nested(struct rw_semaphore *sem, int subclass); +extern void down_write_nested(struct rw_semaphore *sem, int subclass); +/* + * Take/release a lock when not the owner will release it: + */ +extern void down_read_non_owner(struct rw_semaphore *sem); +extern void up_read_non_owner(struct rw_semaphore *sem); +#else +# define down_read_nested(sem, subclass) down_read(sem) +# define down_write_nested(sem, subclass) down_write(sem) +# define down_read_non_owner(sem) down_read(sem) +# define up_read_non_owner(sem) up_read(sem) +#endif #endif /* __KERNEL__ */ #endif /* _LINUX_RWSEM_H */ diff --git a/kernel/Makefile b/kernel/Makefile index 3dd994e..df6ef32 100644 --- a/kernel/Makefile +++ b/kernel/Makefile @@ -8,7 +8,7 @@ obj-y = sched.o fork.o exec_domain.o panic.o printk.o profile.o \ signal.o sys.o kmod.o workqueue.o pid.o \ rcupdate.o extable.o params.o posix-timers.o \ kthread.o wait.o kfifo.o sys_ni.o posix-cpu-timers.o mutex.o \ - hrtimer.o + hrtimer.o rwsem.o obj-$(CONFIG_STACKTRACE) += stacktrace.o obj-y += time/ diff --git a/kernel/rwsem.c b/kernel/rwsem.c index 790a99b..291ded5 100644 --- a/kernel/rwsem.c +++ b/kernel/rwsem.c @@ -103,3 +103,45 @@ void downgrade_write(struct rw_semaphore *sem) } EXPORT_SYMBOL(downgrade_write); + +#ifdef CONFIG_DEBUG_LOCK_ALLOC + +void down_read_nested(struct rw_semaphore *sem, int subclass) +{ + might_sleep(); + rwsem_acquire_read(&sem->dep_map, subclass, 0, _RET_IP_); + + __down_read(sem); +} + +EXPORT_SYMBOL(down_read_nested); + +void down_read_non_owner(struct rw_semaphore *sem) +{ + might_sleep(); + + __down_read(sem); +} + +EXPORT_SYMBOL(down_read_non_owner); + +void down_write_nested(struct rw_semaphore *sem, int subclass) +{ + might_sleep(); + rwsem_acquire(&sem->dep_map, subclass, 0, _RET_IP_); + + __down_write_nested(sem, subclass); +} + +EXPORT_SYMBOL(down_write_nested); + +void up_read_non_owner(struct rw_semaphore *sem) +{ + __up_read(sem); +} + +EXPORT_SYMBOL(up_read_non_owner); + +#endif + + diff --git a/lib/rwsem-spinlock.c b/lib/rwsem-spinlock.c index 03b6097..db4fed7 100644 --- a/lib/rwsem-spinlock.c +++ b/lib/rwsem-spinlock.c @@ -20,8 +20,16 @@ struct rwsem_waiter { /* * initialise the semaphore */ -void fastcall init_rwsem(struct rw_semaphore *sem) +void __init_rwsem(struct rw_semaphore *sem, const char *name, + struct lock_class_key *key) { +#ifdef CONFIG_DEBUG_LOCK_ALLOC + /* + * Make sure we are not reinitializing a held semaphore: + */ + debug_check_no_locks_freed((void *)sem, sizeof(*sem)); + lockdep_init_map(&sem->dep_map, name, key); +#endif sem->activity = 0; spin_lock_init(&sem->wait_lock); INIT_LIST_HEAD(&sem->wait_list); @@ -183,7 +191,7 @@ int fastcall __down_read_trylock(struct rw_semaphore *sem) * get a write lock on the semaphore * - we increment the waiting count anyway to indicate an exclusive lock */ -void fastcall __sched __down_write(struct rw_semaphore *sem) +void fastcall __sched __down_write_nested(struct rw_semaphore *sem, int subclass) { struct rwsem_waiter waiter; struct task_struct *tsk; @@ -223,6 +231,11 @@ void fastcall __sched __down_write(struct rw_semaphore *sem) ; } +void fastcall __sched __down_write(struct rw_semaphore *sem) +{ + __down_write_nested(sem, 0); +} + /* * trylock for writing -- returns 1 if successful, 0 if contention */ @@ -292,9 +305,10 @@ void fastcall __downgrade_write(struct rw_semaphore *sem) spin_unlock_irqrestore(&sem->wait_lock, flags); } -EXPORT_SYMBOL(init_rwsem); +EXPORT_SYMBOL(__init_rwsem); EXPORT_SYMBOL(__down_read); EXPORT_SYMBOL(__down_read_trylock); +EXPORT_SYMBOL(__down_write_nested); EXPORT_SYMBOL(__down_write); EXPORT_SYMBOL(__down_write_trylock); EXPORT_SYMBOL(__up_read); diff --git a/lib/rwsem.c b/lib/rwsem.c index bae5972..b322421 100644 --- a/lib/rwsem.c +++ b/lib/rwsem.c @@ -8,6 +8,26 @@ #include <linux/init.h> #include <linux/module.h> +/* + * Initialize an rwsem: + */ +void __init_rwsem(struct rw_semaphore *sem, const char *name, + struct lock_class_key *key) +{ +#ifdef CONFIG_DEBUG_LOCK_ALLOC + /* + * Make sure we are not reinitializing a held semaphore: + */ + debug_check_no_locks_freed((void *)sem, sizeof(*sem)); + lockdep_init_map(&sem->dep_map, name, key); +#endif + sem->count = RWSEM_UNLOCKED_VALUE; + spin_lock_init(&sem->wait_lock); + INIT_LIST_HEAD(&sem->wait_list); +} + +EXPORT_SYMBOL(__init_rwsem); + struct rwsem_waiter { struct list_head list; struct task_struct *task; |