Merge branch 'core-locking-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip
* 'core-locking-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: rtmutex: tester: Remove the remaining BKL leftovers lockdep/timers: Explain in detail the locking problems del_timer_sync() may cause rtmutex: Simplify PI algorithm and make highest prio task get lock rwsem: Remove redundant asmregparm annotation rwsem: Move duplicate function prototypes to linux/rwsem.h rwsem: Unify the duplicate rwsem_is_locked() inlines rwsem: Move duplicate init macros and functions to linux/rwsem.h rwsem: Move duplicate struct rwsem declaration to linux/rwsem.h x86: Cleanup rwsem_count_t typedef rwsem: Cleanup includes locking: Remove deprecated lock initializers cred: Replace deprecated spinlock initialization kthread: Replace deprecated spinlock initialization xtensa: Replace deprecated spinlock initialization um: Replace deprecated spinlock initialization sparc: Replace deprecated spinlock initialization mips: Replace deprecated spinlock initialization cris: Replace deprecated spinlock initialization alpha: Replace deprecated spinlock initialization rtmutex-tester: Remove BKL tests
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@@ -37,26 +37,9 @@
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#endif
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#ifdef __KERNEL__
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#include <linux/list.h>
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#include <linux/spinlock.h>
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#include <linux/lockdep.h>
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#include <asm/asm.h>
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struct rwsem_waiter;
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extern asmregparm struct rw_semaphore *
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rwsem_down_read_failed(struct rw_semaphore *sem);
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extern asmregparm struct rw_semaphore *
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rwsem_down_write_failed(struct rw_semaphore *sem);
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extern asmregparm struct rw_semaphore *
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rwsem_wake(struct rw_semaphore *);
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extern asmregparm struct rw_semaphore *
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rwsem_downgrade_wake(struct rw_semaphore *sem);
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/*
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* the semaphore definition
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*
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* The bias values and the counter type limits the number of
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* potential readers/writers to 32767 for 32 bits and 2147483647
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* for 64 bits.
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@@ -74,43 +57,6 @@ extern asmregparm struct rw_semaphore *
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#define RWSEM_ACTIVE_READ_BIAS RWSEM_ACTIVE_BIAS
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#define RWSEM_ACTIVE_WRITE_BIAS (RWSEM_WAITING_BIAS + RWSEM_ACTIVE_BIAS)
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typedef signed long rwsem_count_t;
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struct rw_semaphore {
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rwsem_count_t count;
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spinlock_t wait_lock;
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struct list_head wait_list;
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#ifdef CONFIG_DEBUG_LOCK_ALLOC
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struct lockdep_map dep_map;
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#endif
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};
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#ifdef CONFIG_DEBUG_LOCK_ALLOC
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# define __RWSEM_DEP_MAP_INIT(lockname) , .dep_map = { .name = #lockname }
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#else
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# define __RWSEM_DEP_MAP_INIT(lockname)
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#endif
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#define __RWSEM_INITIALIZER(name) \
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{ \
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RWSEM_UNLOCKED_VALUE, __SPIN_LOCK_UNLOCKED((name).wait_lock), \
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LIST_HEAD_INIT((name).wait_list) __RWSEM_DEP_MAP_INIT(name) \
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}
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#define DECLARE_RWSEM(name) \
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struct rw_semaphore name = __RWSEM_INITIALIZER(name)
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extern void __init_rwsem(struct rw_semaphore *sem, const char *name,
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struct lock_class_key *key);
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#define init_rwsem(sem) \
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do { \
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static struct lock_class_key __key; \
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\
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__init_rwsem((sem), #sem, &__key); \
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} while (0)
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/*
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* lock for reading
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*/
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@@ -133,7 +79,7 @@ static inline void __down_read(struct rw_semaphore *sem)
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*/
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static inline int __down_read_trylock(struct rw_semaphore *sem)
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{
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rwsem_count_t result, tmp;
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long result, tmp;
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asm volatile("# beginning __down_read_trylock\n\t"
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" mov %0,%1\n\t"
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"1:\n\t"
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@@ -155,7 +101,7 @@ static inline int __down_read_trylock(struct rw_semaphore *sem)
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*/
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static inline void __down_write_nested(struct rw_semaphore *sem, int subclass)
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{
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rwsem_count_t tmp;
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long tmp;
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asm volatile("# beginning down_write\n\t"
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LOCK_PREFIX " xadd %1,(%2)\n\t"
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/* adds 0xffff0001, returns the old value */
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@@ -180,9 +126,8 @@ static inline void __down_write(struct rw_semaphore *sem)
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*/
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static inline int __down_write_trylock(struct rw_semaphore *sem)
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{
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rwsem_count_t ret = cmpxchg(&sem->count,
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RWSEM_UNLOCKED_VALUE,
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RWSEM_ACTIVE_WRITE_BIAS);
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long ret = cmpxchg(&sem->count, RWSEM_UNLOCKED_VALUE,
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RWSEM_ACTIVE_WRITE_BIAS);
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if (ret == RWSEM_UNLOCKED_VALUE)
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return 1;
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return 0;
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@@ -193,7 +138,7 @@ static inline int __down_write_trylock(struct rw_semaphore *sem)
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*/
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static inline void __up_read(struct rw_semaphore *sem)
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{
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rwsem_count_t tmp;
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long tmp;
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asm volatile("# beginning __up_read\n\t"
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LOCK_PREFIX " xadd %1,(%2)\n\t"
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/* subtracts 1, returns the old value */
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@@ -211,7 +156,7 @@ static inline void __up_read(struct rw_semaphore *sem)
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*/
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static inline void __up_write(struct rw_semaphore *sem)
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{
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rwsem_count_t tmp;
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long tmp;
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asm volatile("# beginning __up_write\n\t"
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LOCK_PREFIX " xadd %1,(%2)\n\t"
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/* subtracts 0xffff0001, returns the old value */
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@@ -247,8 +192,7 @@ static inline void __downgrade_write(struct rw_semaphore *sem)
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/*
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* implement atomic add functionality
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*/
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static inline void rwsem_atomic_add(rwsem_count_t delta,
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struct rw_semaphore *sem)
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static inline void rwsem_atomic_add(long delta, struct rw_semaphore *sem)
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{
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asm volatile(LOCK_PREFIX _ASM_ADD "%1,%0"
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: "+m" (sem->count)
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@@ -258,10 +202,9 @@ static inline void rwsem_atomic_add(rwsem_count_t delta,
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/*
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* implement exchange and add functionality
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*/
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static inline rwsem_count_t rwsem_atomic_update(rwsem_count_t delta,
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struct rw_semaphore *sem)
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static inline long rwsem_atomic_update(long delta, struct rw_semaphore *sem)
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{
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rwsem_count_t tmp = delta;
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long tmp = delta;
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asm volatile(LOCK_PREFIX "xadd %0,%1"
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: "+r" (tmp), "+m" (sem->count)
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@@ -270,10 +213,5 @@ static inline rwsem_count_t rwsem_atomic_update(rwsem_count_t delta,
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return tmp + delta;
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}
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static inline int rwsem_is_locked(struct rw_semaphore *sem)
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{
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return (sem->count != 0);
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}
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#endif /* __KERNEL__ */
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#endif /* _ASM_X86_RWSEM_H */
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