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Diffstat (limited to 'arch/s390/include/asm/atomic.h')
-rw-r--r-- | arch/s390/include/asm/atomic.h | 285 |
1 files changed, 285 insertions, 0 deletions
diff --git a/arch/s390/include/asm/atomic.h b/arch/s390/include/asm/atomic.h new file mode 100644 index 000000000000..2d184655bc5d --- /dev/null +++ b/arch/s390/include/asm/atomic.h @@ -0,0 +1,285 @@ +#ifndef __ARCH_S390_ATOMIC__ +#define __ARCH_S390_ATOMIC__ + +#include <linux/compiler.h> + +/* + * include/asm-s390/atomic.h + * + * S390 version + * Copyright (C) 1999-2005 IBM Deutschland Entwicklung GmbH, IBM Corporation + * Author(s): Martin Schwidefsky (schwidefsky@de.ibm.com), + * Denis Joseph Barrow, + * Arnd Bergmann (arndb@de.ibm.com) + * + * Derived from "include/asm-i386/bitops.h" + * Copyright (C) 1992, Linus Torvalds + * + */ + +/* + * Atomic operations that C can't guarantee us. Useful for + * resource counting etc.. + * S390 uses 'Compare And Swap' for atomicity in SMP enviroment + */ + +typedef struct { + int counter; +} __attribute__ ((aligned (4))) atomic_t; +#define ATOMIC_INIT(i) { (i) } + +#ifdef __KERNEL__ + +#if __GNUC__ > 3 || (__GNUC__ == 3 && __GNUC_MINOR__ > 2) + +#define __CS_LOOP(ptr, op_val, op_string) ({ \ + typeof(ptr->counter) old_val, new_val; \ + asm volatile( \ + " l %0,%2\n" \ + "0: lr %1,%0\n" \ + op_string " %1,%3\n" \ + " cs %0,%1,%2\n" \ + " jl 0b" \ + : "=&d" (old_val), "=&d" (new_val), \ + "=Q" (((atomic_t *)(ptr))->counter) \ + : "d" (op_val), "Q" (((atomic_t *)(ptr))->counter) \ + : "cc", "memory"); \ + new_val; \ +}) + +#else /* __GNUC__ */ + +#define __CS_LOOP(ptr, op_val, op_string) ({ \ + typeof(ptr->counter) old_val, new_val; \ + asm volatile( \ + " l %0,0(%3)\n" \ + "0: lr %1,%0\n" \ + op_string " %1,%4\n" \ + " cs %0,%1,0(%3)\n" \ + " jl 0b" \ + : "=&d" (old_val), "=&d" (new_val), \ + "=m" (((atomic_t *)(ptr))->counter) \ + : "a" (ptr), "d" (op_val), \ + "m" (((atomic_t *)(ptr))->counter) \ + : "cc", "memory"); \ + new_val; \ +}) + +#endif /* __GNUC__ */ + +static inline int atomic_read(const atomic_t *v) +{ + barrier(); + return v->counter; +} + +static inline void atomic_set(atomic_t *v, int i) +{ + v->counter = i; + barrier(); +} + +static __inline__ int atomic_add_return(int i, atomic_t * v) +{ + return __CS_LOOP(v, i, "ar"); +} +#define atomic_add(_i, _v) atomic_add_return(_i, _v) +#define atomic_add_negative(_i, _v) (atomic_add_return(_i, _v) < 0) +#define atomic_inc(_v) atomic_add_return(1, _v) +#define atomic_inc_return(_v) atomic_add_return(1, _v) +#define atomic_inc_and_test(_v) (atomic_add_return(1, _v) == 0) + +static __inline__ int atomic_sub_return(int i, atomic_t * v) +{ + return __CS_LOOP(v, i, "sr"); +} +#define atomic_sub(_i, _v) atomic_sub_return(_i, _v) +#define atomic_sub_and_test(_i, _v) (atomic_sub_return(_i, _v) == 0) +#define atomic_dec(_v) atomic_sub_return(1, _v) +#define atomic_dec_return(_v) atomic_sub_return(1, _v) +#define atomic_dec_and_test(_v) (atomic_sub_return(1, _v) == 0) + +static __inline__ void atomic_clear_mask(unsigned long mask, atomic_t * v) +{ + __CS_LOOP(v, ~mask, "nr"); +} + +static __inline__ void atomic_set_mask(unsigned long mask, atomic_t * v) +{ + __CS_LOOP(v, mask, "or"); +} + +#define atomic_xchg(v, new) (xchg(&((v)->counter), new)) + +static __inline__ int atomic_cmpxchg(atomic_t *v, int old, int new) +{ +#if __GNUC__ > 3 || (__GNUC__ == 3 && __GNUC_MINOR__ > 2) + asm volatile( + " cs %0,%2,%1" + : "+d" (old), "=Q" (v->counter) + : "d" (new), "Q" (v->counter) + : "cc", "memory"); +#else /* __GNUC__ */ + asm volatile( + " cs %0,%3,0(%2)" + : "+d" (old), "=m" (v->counter) + : "a" (v), "d" (new), "m" (v->counter) + : "cc", "memory"); +#endif /* __GNUC__ */ + return old; +} + +static __inline__ int atomic_add_unless(atomic_t *v, int a, int u) +{ + int c, old; + c = atomic_read(v); + for (;;) { + if (unlikely(c == u)) + break; + old = atomic_cmpxchg(v, c, c + a); + if (likely(old == c)) + break; + c = old; + } + return c != u; +} + +#define atomic_inc_not_zero(v) atomic_add_unless((v), 1, 0) + +#undef __CS_LOOP + +#ifdef __s390x__ +typedef struct { + long long counter; +} __attribute__ ((aligned (8))) atomic64_t; +#define ATOMIC64_INIT(i) { (i) } + +#if __GNUC__ > 3 || (__GNUC__ == 3 && __GNUC_MINOR__ > 2) + +#define __CSG_LOOP(ptr, op_val, op_string) ({ \ + typeof(ptr->counter) old_val, new_val; \ + asm volatile( \ + " lg %0,%2\n" \ + "0: lgr %1,%0\n" \ + op_string " %1,%3\n" \ + " csg %0,%1,%2\n" \ + " jl 0b" \ + : "=&d" (old_val), "=&d" (new_val), \ + "=Q" (((atomic_t *)(ptr))->counter) \ + : "d" (op_val), "Q" (((atomic_t *)(ptr))->counter) \ + : "cc", "memory" ); \ + new_val; \ +}) + +#else /* __GNUC__ */ + +#define __CSG_LOOP(ptr, op_val, op_string) ({ \ + typeof(ptr->counter) old_val, new_val; \ + asm volatile( \ + " lg %0,0(%3)\n" \ + "0: lgr %1,%0\n" \ + op_string " %1,%4\n" \ + " csg %0,%1,0(%3)\n" \ + " jl 0b" \ + : "=&d" (old_val), "=&d" (new_val), \ + "=m" (((atomic_t *)(ptr))->counter) \ + : "a" (ptr), "d" (op_val), \ + "m" (((atomic_t *)(ptr))->counter) \ + : "cc", "memory" ); \ + new_val; \ +}) + +#endif /* __GNUC__ */ + +static inline long long atomic64_read(const atomic64_t *v) +{ + barrier(); + return v->counter; +} + +static inline void atomic64_set(atomic64_t *v, long long i) +{ + v->counter = i; + barrier(); +} + +static __inline__ long long atomic64_add_return(long long i, atomic64_t * v) +{ + return __CSG_LOOP(v, i, "agr"); +} +#define atomic64_add(_i, _v) atomic64_add_return(_i, _v) +#define atomic64_add_negative(_i, _v) (atomic64_add_return(_i, _v) < 0) +#define atomic64_inc(_v) atomic64_add_return(1, _v) +#define atomic64_inc_return(_v) atomic64_add_return(1, _v) +#define atomic64_inc_and_test(_v) (atomic64_add_return(1, _v) == 0) + +static __inline__ long long atomic64_sub_return(long long i, atomic64_t * v) +{ + return __CSG_LOOP(v, i, "sgr"); +} +#define atomic64_sub(_i, _v) atomic64_sub_return(_i, _v) +#define atomic64_sub_and_test(_i, _v) (atomic64_sub_return(_i, _v) == 0) +#define atomic64_dec(_v) atomic64_sub_return(1, _v) +#define atomic64_dec_return(_v) atomic64_sub_return(1, _v) +#define atomic64_dec_and_test(_v) (atomic64_sub_return(1, _v) == 0) + +static __inline__ void atomic64_clear_mask(unsigned long mask, atomic64_t * v) +{ + __CSG_LOOP(v, ~mask, "ngr"); +} + +static __inline__ void atomic64_set_mask(unsigned long mask, atomic64_t * v) +{ + __CSG_LOOP(v, mask, "ogr"); +} + +#define atomic64_xchg(v, new) (xchg(&((v)->counter), new)) + +static __inline__ long long atomic64_cmpxchg(atomic64_t *v, + long long old, long long new) +{ +#if __GNUC__ > 3 || (__GNUC__ == 3 && __GNUC_MINOR__ > 2) + asm volatile( + " csg %0,%2,%1" + : "+d" (old), "=Q" (v->counter) + : "d" (new), "Q" (v->counter) + : "cc", "memory"); +#else /* __GNUC__ */ + asm volatile( + " csg %0,%3,0(%2)" + : "+d" (old), "=m" (v->counter) + : "a" (v), "d" (new), "m" (v->counter) + : "cc", "memory"); +#endif /* __GNUC__ */ + return old; +} + +static __inline__ int atomic64_add_unless(atomic64_t *v, + long long a, long long u) +{ + long long c, old; + c = atomic64_read(v); + for (;;) { + if (unlikely(c == u)) + break; + old = atomic64_cmpxchg(v, c, c + a); + if (likely(old == c)) + break; + c = old; + } + return c != u; +} + +#define atomic64_inc_not_zero(v) atomic64_add_unless((v), 1, 0) + +#undef __CSG_LOOP +#endif + +#define smp_mb__before_atomic_dec() smp_mb() +#define smp_mb__after_atomic_dec() smp_mb() +#define smp_mb__before_atomic_inc() smp_mb() +#define smp_mb__after_atomic_inc() smp_mb() + +#include <asm-generic/atomic.h> +#endif /* __KERNEL__ */ +#endif /* __ARCH_S390_ATOMIC__ */ |