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Diffstat (limited to 'include/asm-s390/atomic.h')
| -rw-r--r-- | include/asm-s390/atomic.h | 207 |
1 files changed, 207 insertions, 0 deletions
diff --git a/include/asm-s390/atomic.h b/include/asm-s390/atomic.h new file mode 100644 index 000000000000..d5a05cf47168 --- /dev/null +++ b/include/asm-s390/atomic.h @@ -0,0 +1,207 @@ +#ifndef __ARCH_S390_ATOMIC__ +#define __ARCH_S390_ATOMIC__ + +/* + * include/asm-s390/atomic.h + * + * S390 version + * Copyright (C) 1999-2003 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 { + volatile int counter; +} __attribute__ ((aligned (4))) atomic_t; +#define ATOMIC_INIT(i) { (i) } + +#ifdef __KERNEL__ + +#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; \ +}) +#define atomic_read(v) ((v)->counter) +#define atomic_set(v,i) (((v)->counter) = (i)) + +static __inline__ void atomic_add(int i, atomic_t * v) +{ + __CS_LOOP(v, i, "ar"); +} +static __inline__ int atomic_add_return(int i, atomic_t * v) +{ + return __CS_LOOP(v, i, "ar"); +} +static __inline__ int atomic_add_negative(int i, atomic_t * v) +{ + return __CS_LOOP(v, i, "ar") < 0; +} +static __inline__ void atomic_sub(int i, atomic_t * v) +{ + __CS_LOOP(v, i, "sr"); +} +static __inline__ int atomic_sub_return(int i, atomic_t * v) +{ + return __CS_LOOP(v, i, "sr"); +} +static __inline__ void atomic_inc(volatile atomic_t * v) +{ + __CS_LOOP(v, 1, "ar"); +} +static __inline__ int atomic_inc_return(volatile atomic_t * v) +{ + return __CS_LOOP(v, 1, "ar"); +} + +static __inline__ int atomic_inc_and_test(volatile atomic_t * v) +{ + return __CS_LOOP(v, 1, "ar") == 0; +} +static __inline__ void atomic_dec(volatile atomic_t * v) +{ + __CS_LOOP(v, 1, "sr"); +} +static __inline__ int atomic_dec_return(volatile atomic_t * v) +{ + return __CS_LOOP(v, 1, "sr"); +} +static __inline__ int atomic_dec_and_test(volatile atomic_t * v) +{ + return __CS_LOOP(v, 1, "sr") == 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"); +} +#undef __CS_LOOP + +#ifdef __s390x__ +typedef struct { + volatile long long counter; +} __attribute__ ((aligned (8))) atomic64_t; +#define ATOMIC64_INIT(i) { (i) } + +#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; \ +}) +#define atomic64_read(v) ((v)->counter) +#define atomic64_set(v,i) (((v)->counter) = (i)) + +static __inline__ void atomic64_add(int i, atomic64_t * v) +{ + __CSG_LOOP(v, i, "agr"); +} +static __inline__ long long atomic64_add_return(int i, atomic64_t * v) +{ + return __CSG_LOOP(v, i, "agr"); +} +static __inline__ long long atomic64_add_negative(int i, atomic64_t * v) +{ + return __CSG_LOOP(v, i, "agr") < 0; +} +static __inline__ void atomic64_sub(int i, atomic64_t * v) +{ + __CSG_LOOP(v, i, "sgr"); +} +static __inline__ void atomic64_inc(volatile atomic64_t * v) +{ + __CSG_LOOP(v, 1, "agr"); +} +static __inline__ long long atomic64_inc_return(volatile atomic64_t * v) +{ + return __CSG_LOOP(v, 1, "agr"); +} +static __inline__ long long atomic64_inc_and_test(volatile atomic64_t * v) +{ + return __CSG_LOOP(v, 1, "agr") == 0; +} +static __inline__ void atomic64_dec(volatile atomic64_t * v) +{ + __CSG_LOOP(v, 1, "sgr"); +} +static __inline__ long long atomic64_dec_return(volatile atomic64_t * v) +{ + return __CSG_LOOP(v, 1, "sgr"); +} +static __inline__ long long atomic64_dec_and_test(volatile atomic64_t * v) +{ + return __CSG_LOOP(v, 1, "sgr") == 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"); +} + +#undef __CSG_LOOP +#endif + +/* + returns 0 if expected_oldval==value in *v ( swap was successful ) + returns 1 if unsuccessful. + + This is non-portable, use bitops or spinlocks instead! +*/ +static __inline__ int +atomic_compare_and_swap(int expected_oldval,int new_val,atomic_t *v) +{ + int retval; + + __asm__ __volatile__( + " lr %0,%3\n" + " cs %0,%4,0(%2)\n" + " ipm %0\n" + " srl %0,28\n" + "0:" + : "=&d" (retval), "=m" (v->counter) + : "a" (v), "d" (expected_oldval) , "d" (new_val), + "m" (v->counter) : "cc", "memory" ); + return retval; +} + +#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() + +#endif /* __KERNEL__ */ +#endif /* __ARCH_S390_ATOMIC__ */ |