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Diffstat (limited to 'include/asm-s390/spinlock.h')
| -rw-r--r-- | include/asm-s390/spinlock.h | 178 |
1 files changed, 0 insertions, 178 deletions
diff --git a/include/asm-s390/spinlock.h b/include/asm-s390/spinlock.h deleted file mode 100644 index df84ae96915f..000000000000 --- a/include/asm-s390/spinlock.h +++ /dev/null @@ -1,178 +0,0 @@ -/* - * include/asm-s390/spinlock.h - * - * S390 version - * Copyright (C) 1999 IBM Deutschland Entwicklung GmbH, IBM Corporation - * Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com) - * - * Derived from "include/asm-i386/spinlock.h" - */ - -#ifndef __ASM_SPINLOCK_H -#define __ASM_SPINLOCK_H - -#include <linux/smp.h> - -#if __GNUC__ > 3 || (__GNUC__ == 3 && __GNUC_MINOR__ > 2) - -static inline int -_raw_compare_and_swap(volatile unsigned int *lock, - unsigned int old, unsigned int new) -{ - asm volatile( - " cs %0,%3,%1" - : "=d" (old), "=Q" (*lock) - : "0" (old), "d" (new), "Q" (*lock) - : "cc", "memory" ); - return old; -} - -#else /* __GNUC__ */ - -static inline int -_raw_compare_and_swap(volatile unsigned int *lock, - unsigned int old, unsigned int new) -{ - asm volatile( - " cs %0,%3,0(%4)" - : "=d" (old), "=m" (*lock) - : "0" (old), "d" (new), "a" (lock), "m" (*lock) - : "cc", "memory" ); - return old; -} - -#endif /* __GNUC__ */ - -/* - * Simple spin lock operations. There are two variants, one clears IRQ's - * on the local processor, one does not. - * - * We make no fairness assumptions. They have a cost. - * - * (the type definitions are in asm/spinlock_types.h) - */ - -#define __raw_spin_is_locked(x) ((x)->owner_cpu != 0) -#define __raw_spin_unlock_wait(lock) \ - do { while (__raw_spin_is_locked(lock)) \ - _raw_spin_relax(lock); } while (0) - -extern void _raw_spin_lock_wait(raw_spinlock_t *); -extern void _raw_spin_lock_wait_flags(raw_spinlock_t *, unsigned long flags); -extern int _raw_spin_trylock_retry(raw_spinlock_t *); -extern void _raw_spin_relax(raw_spinlock_t *lock); - -static inline void __raw_spin_lock(raw_spinlock_t *lp) -{ - int old; - - old = _raw_compare_and_swap(&lp->owner_cpu, 0, ~smp_processor_id()); - if (likely(old == 0)) - return; - _raw_spin_lock_wait(lp); -} - -static inline void __raw_spin_lock_flags(raw_spinlock_t *lp, - unsigned long flags) -{ - int old; - - old = _raw_compare_and_swap(&lp->owner_cpu, 0, ~smp_processor_id()); - if (likely(old == 0)) - return; - _raw_spin_lock_wait_flags(lp, flags); -} - -static inline int __raw_spin_trylock(raw_spinlock_t *lp) -{ - int old; - - old = _raw_compare_and_swap(&lp->owner_cpu, 0, ~smp_processor_id()); - if (likely(old == 0)) - return 1; - return _raw_spin_trylock_retry(lp); -} - -static inline void __raw_spin_unlock(raw_spinlock_t *lp) -{ - _raw_compare_and_swap(&lp->owner_cpu, lp->owner_cpu, 0); -} - -/* - * Read-write spinlocks, allowing multiple readers - * but only one writer. - * - * NOTE! it is quite common to have readers in interrupts - * but no interrupt writers. For those circumstances we - * can "mix" irq-safe locks - any writer needs to get a - * irq-safe write-lock, but readers can get non-irqsafe - * read-locks. - */ - -/** - * read_can_lock - would read_trylock() succeed? - * @lock: the rwlock in question. - */ -#define __raw_read_can_lock(x) ((int)(x)->lock >= 0) - -/** - * write_can_lock - would write_trylock() succeed? - * @lock: the rwlock in question. - */ -#define __raw_write_can_lock(x) ((x)->lock == 0) - -extern void _raw_read_lock_wait(raw_rwlock_t *lp); -extern int _raw_read_trylock_retry(raw_rwlock_t *lp); -extern void _raw_write_lock_wait(raw_rwlock_t *lp); -extern int _raw_write_trylock_retry(raw_rwlock_t *lp); - -static inline void __raw_read_lock(raw_rwlock_t *rw) -{ - unsigned int old; - old = rw->lock & 0x7fffffffU; - if (_raw_compare_and_swap(&rw->lock, old, old + 1) != old) - _raw_read_lock_wait(rw); -} - -static inline void __raw_read_unlock(raw_rwlock_t *rw) -{ - unsigned int old, cmp; - - old = rw->lock; - do { - cmp = old; - old = _raw_compare_and_swap(&rw->lock, old, old - 1); - } while (cmp != old); -} - -static inline void __raw_write_lock(raw_rwlock_t *rw) -{ - if (unlikely(_raw_compare_and_swap(&rw->lock, 0, 0x80000000) != 0)) - _raw_write_lock_wait(rw); -} - -static inline void __raw_write_unlock(raw_rwlock_t *rw) -{ - _raw_compare_and_swap(&rw->lock, 0x80000000, 0); -} - -static inline int __raw_read_trylock(raw_rwlock_t *rw) -{ - unsigned int old; - old = rw->lock & 0x7fffffffU; - if (likely(_raw_compare_and_swap(&rw->lock, old, old + 1) == old)) - return 1; - return _raw_read_trylock_retry(rw); -} - -static inline int __raw_write_trylock(raw_rwlock_t *rw) -{ - if (likely(_raw_compare_and_swap(&rw->lock, 0, 0x80000000) == 0)) - return 1; - return _raw_write_trylock_retry(rw); -} - -#define _raw_read_relax(lock) cpu_relax() -#define _raw_write_relax(lock) cpu_relax() - -#endif /* __ASM_SPINLOCK_H */ |