#ifndef _ALPHA_ATOMIC_H #define _ALPHA_ATOMIC_H #include <linux/types.h> #include <asm/barrier.h> /* * Atomic operations that C can't guarantee us. Useful for * resource counting etc... * * But use these as seldom as possible since they are much slower * than regular operations. */ #define ATOMIC_INIT(i) ( (atomic_t) { (i) } ) #define ATOMIC64_INIT(i) ( (atomic64_t) { (i) } ) #define atomic_read(v) (*(volatile int *)&(v)->counter) #define atomic64_read(v) (*(volatile long *)&(v)->counter) #define atomic_set(v,i) ((v)->counter = (i)) #define atomic64_set(v,i) ((v)->counter = (i)) /* * To get proper branch prediction for the main line, we must branch * forward to code at the end of this object's .text section, then * branch back to restart the operation. */ static __inline__ void atomic_add(int i, atomic_t * v) { unsigned long temp; __asm__ __volatile__( "1: ldl_l %0,%1\n" " addl %0,%2,%0\n" " stl_c %0,%1\n" " beq %0,2f\n" ".subsection 2\n" "2: br 1b\n" ".previous" :"=&r" (temp), "=m" (v->counter) :"Ir" (i), "m" (v->counter)); } static __inline__ void atomic64_add(long i, atomic64_t * v) { unsigned long temp; __asm__ __volatile__( "1: ldq_l %0,%1\n" " addq %0,%2,%0\n" " stq_c %0,%1\n" " beq %0,2f\n" ".subsection 2\n" "2: br 1b\n" ".previous" :"=&r" (temp), "=m" (v->counter) :"Ir" (i), "m" (v->counter)); } static __inline__ void atomic_sub(int i, atomic_t * v) { unsigned long temp; __asm__ __volatile__( "1: ldl_l %0,%1\n" " subl %0,%2,%0\n" " stl_c %0,%1\n" " beq %0,2f\n" ".subsection 2\n" "2: br 1b\n" ".previous" :"=&r" (temp), "=m" (v->counter) :"Ir" (i), "m" (v->counter)); } static __inline__ void atomic64_sub(long i, atomic64_t * v) { unsigned long temp; __asm__ __volatile__( "1: ldq_l %0,%1\n" " subq %0,%2,%0\n" " stq_c %0,%1\n" " beq %0,2f\n" ".subsection 2\n" "2: br 1b\n" ".previous" :"=&r" (temp), "=m" (v->counter) :"Ir" (i), "m" (v->counter)); } /* * Same as above, but return the result value */ static inline int atomic_add_return(int i, atomic_t *v) { long temp, result; smp_mb(); __asm__ __volatile__( "1: ldl_l %0,%1\n" " addl %0,%3,%2\n" " addl %0,%3,%0\n" " stl_c %0,%1\n" " beq %0,2f\n" ".subsection 2\n" "2: br 1b\n" ".previous" :"=&r" (temp), "=m" (v->counter), "=&r" (result) :"Ir" (i), "m" (v->counter) : "memory"); smp_mb(); return result; } static __inline__ long atomic64_add_return(long i, atomic64_t * v) { long temp, result; smp_mb(); __asm__ __volatile__( "1: ldq_l %0,%1\n" " addq %0,%3,%2\n" " addq %0,%3,%0\n" " stq_c %0,%1\n" " beq %0,2f\n" ".subsection 2\n" "2: br 1b\n" ".previous" :"=&r" (temp), "=m" (v->counter), "=&r" (result) :"Ir" (i), "m" (v->counter) : "memory"); smp_mb(); return result; } static __inline__ long atomic_sub_return(int i, atomic_t * v) { long temp, result; smp_mb(); __asm__ __volatile__( "1: ldl_l %0,%1\n" " subl %0,%3,%2\n" " subl %0,%3,%0\n" " stl_c %0,%1\n" " beq %0,2f\n" ".subsection 2\n" "2: br 1b\n" ".previous" :"=&r" (temp), "=m" (v->counter), "=&r" (result) :"Ir" (i), "m" (v->counter) : "memory"); smp_mb(); return result; } static __inline__ long atomic64_sub_return(long i, atomic64_t * v) { long temp, result; smp_mb(); __asm__ __volatile__( "1: ldq_l %0,%1\n" " subq %0,%3,%2\n" " subq %0,%3,%0\n" " stq_c %0,%1\n" " beq %0,2f\n" ".subsection 2\n" "2: br 1b\n" ".previous" :"=&r" (temp), "=m" (v->counter), "=&r" (result) :"Ir" (i), "m" (v->counter) : "memory"); smp_mb(); return result; } /* * Atomic exchange routines. */ #define __ASM__MB #define ____xchg(type, args...) __xchg ## type ## _local(args) #define ____cmpxchg(type, args...) __cmpxchg ## type ## _local(args) #include <asm/xchg.h> #define xchg_local(ptr,x) \ ({ \ __typeof__(*(ptr)) _x_ = (x); \ (__typeof__(*(ptr))) __xchg_local((ptr), (unsigned long)_x_, \ sizeof(*(ptr))); \ }) #define cmpxchg_local(ptr, o, n) \ ({ \ __typeof__(*(ptr)) _o_ = (o); \ __typeof__(*(ptr)) _n_ = (n); \ (__typeof__(*(ptr))) __cmpxchg_local((ptr), (unsigned long)_o_, \ (unsigned long)_n_, \ sizeof(*(ptr))); \ }) #define cmpxchg64_local(ptr, o, n) \ ({ \ BUILD_BUG_ON(sizeof(*(ptr)) != 8); \ cmpxchg_local((ptr), (o), (n)); \ }) #ifdef CONFIG_SMP #undef __ASM__MB #define __ASM__MB "\tmb\n" #endif #undef ____xchg #undef ____cmpxchg #define ____xchg(type, args...) __xchg ##type(args) #define ____cmpxchg(type, args...) __cmpxchg ##type(args) #include <asm/xchg.h> #define xchg(ptr,x) \ ({ \ __typeof__(*(ptr)) _x_ = (x); \ (__typeof__(*(ptr))) __xchg((ptr), (unsigned long)_x_, \ sizeof(*(ptr))); \ }) #define cmpxchg(ptr, o, n) \ ({ \ __typeof__(*(ptr)) _o_ = (o); \ __typeof__(*(ptr)) _n_ = (n); \ (__typeof__(*(ptr))) __cmpxchg((ptr), (unsigned long)_o_, \ (unsigned long)_n_, sizeof(*(ptr)));\ }) #define cmpxchg64(ptr, o, n) \ ({ \ BUILD_BUG_ON(sizeof(*(ptr)) != 8); \ cmpxchg((ptr), (o), (n)); \ }) #undef __ASM__MB #undef ____cmpxchg #define __HAVE_ARCH_CMPXCHG 1 #define atomic64_cmpxchg(v, old, new) (cmpxchg(&((v)->counter), old, new)) #define atomic64_xchg(v, new) (xchg(&((v)->counter), new)) #define atomic_cmpxchg(v, old, new) (cmpxchg(&((v)->counter), old, new)) #define atomic_xchg(v, new) (xchg(&((v)->counter), new)) /** * __atomic_add_unless - add unless the number is a given value * @v: pointer of type atomic_t * @a: the amount to add to v... * @u: ...unless v is equal to u. * * Atomically adds @a to @v, so long as it was not @u. * Returns the old value of @v. */ 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; } /** * atomic64_add_unless - add unless the number is a given value * @v: pointer of type atomic64_t * @a: the amount to add to v... * @u: ...unless v is equal to u. * * Atomically adds @a to @v, so long as it was not @u. * Returns the old value of @v. */ static __inline__ int atomic64_add_unless(atomic64_t *v, long a, long u) { 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) #define atomic_add_negative(a, v) (atomic_add_return((a), (v)) < 0) #define atomic64_add_negative(a, v) (atomic64_add_return((a), (v)) < 0) #define atomic_dec_return(v) atomic_sub_return(1,(v)) #define atomic64_dec_return(v) atomic64_sub_return(1,(v)) #define atomic_inc_return(v) atomic_add_return(1,(v)) #define atomic64_inc_return(v) atomic64_add_return(1,(v)) #define atomic_sub_and_test(i,v) (atomic_sub_return((i), (v)) == 0) #define atomic64_sub_and_test(i,v) (atomic64_sub_return((i), (v)) == 0) #define atomic_inc_and_test(v) (atomic_add_return(1, (v)) == 0) #define atomic64_inc_and_test(v) (atomic64_add_return(1, (v)) == 0) #define atomic_dec_and_test(v) (atomic_sub_return(1, (v)) == 0) #define atomic64_dec_and_test(v) (atomic64_sub_return(1, (v)) == 0) #define atomic_inc(v) atomic_add(1,(v)) #define atomic64_inc(v) atomic64_add(1,(v)) #define atomic_dec(v) atomic_sub(1,(v)) #define atomic64_dec(v) atomic64_sub(1,(v)) #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 /* _ALPHA_ATOMIC_H */