diff options
Diffstat (limited to 'include/asm-s390/spinlock.h')
-rw-r--r-- | include/asm-s390/spinlock.h | 62 |
1 files changed, 49 insertions, 13 deletions
diff --git a/include/asm-s390/spinlock.h b/include/asm-s390/spinlock.h index 273dbecf8ace..6b78af16999b 100644 --- a/include/asm-s390/spinlock.h +++ b/include/asm-s390/spinlock.h @@ -11,17 +11,38 @@ #ifndef __ASM_SPINLOCK_H #define __ASM_SPINLOCK_H +#if __GNUC__ > 3 || (__GNUC__ == 3 && __GNUC_MINOR__ > 2) + +#include <linux/smp.h> + 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" ); + 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. @@ -31,34 +52,46 @@ _raw_compare_and_swap(volatile unsigned int *lock, * (the type definitions are in asm/spinlock_types.h) */ -#define __raw_spin_is_locked(x) ((x)->lock != 0) +#define __raw_spin_is_locked(x) ((x)->owner_cpu != 0) #define __raw_spin_lock_flags(lock, flags) __raw_spin_lock(lock) #define __raw_spin_unlock_wait(lock) \ - do { while (__raw_spin_is_locked(lock)) cpu_relax(); } while (0) + do { while (__raw_spin_is_locked(lock)) \ + _raw_spin_relax(lock); } while (0) -extern void _raw_spin_lock_wait(raw_spinlock_t *lp, unsigned int pc); -extern int _raw_spin_trylock_retry(raw_spinlock_t *lp, unsigned int pc); +extern void _raw_spin_lock_wait(raw_spinlock_t *, unsigned int pc); +extern int _raw_spin_trylock_retry(raw_spinlock_t *, unsigned int pc); +extern void _raw_spin_relax(raw_spinlock_t *lock); static inline void __raw_spin_lock(raw_spinlock_t *lp) { unsigned long pc = 1 | (unsigned long) __builtin_return_address(0); - - if (unlikely(_raw_compare_and_swap(&lp->lock, 0, pc) != 0)) - _raw_spin_lock_wait(lp, pc); + int old; + + old = _raw_compare_and_swap(&lp->owner_cpu, 0, ~smp_processor_id()); + if (likely(old == 0)) { + lp->owner_pc = pc; + return; + } + _raw_spin_lock_wait(lp, pc); } static inline int __raw_spin_trylock(raw_spinlock_t *lp) { unsigned long pc = 1 | (unsigned long) __builtin_return_address(0); + int old; - if (likely(_raw_compare_and_swap(&lp->lock, 0, pc) == 0)) + old = _raw_compare_and_swap(&lp->owner_cpu, 0, ~smp_processor_id()); + if (likely(old == 0)) { + lp->owner_pc = pc; return 1; + } return _raw_spin_trylock_retry(lp, pc); } static inline void __raw_spin_unlock(raw_spinlock_t *lp) { - _raw_compare_and_swap(&lp->lock, lp->lock, 0); + lp->owner_pc = 0; + _raw_compare_and_swap(&lp->owner_cpu, lp->owner_cpu, 0); } /* @@ -135,4 +168,7 @@ static inline int __raw_write_trylock(raw_rwlock_t *rw) return _raw_write_trylock_retry(rw); } +#define _raw_read_relax(lock) cpu_relax() +#define _raw_write_relax(lock) cpu_relax() + #endif /* __ASM_SPINLOCK_H */ |