#ifndef _ALPHA_ATOMIC_H #define _ALPHA_ATOMIC_H #include <linux/types.h> #include <asm/barrier.h> #include <asm/cmpxchg.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) { (i) } #define ATOMIC64_INIT(i) { (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; } #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, new, old; smp_mb(); __asm__ __volatile__( "1: ldl_l %[old],%[mem]\n" " cmpeq %[old],%[u],%[c]\n" " addl %[old],%[a],%[new]\n" " bne %[c],2f\n" " stl_c %[new],%[mem]\n" " beq %[new],3f\n" "2:\n" ".subsection 2\n" "3: br 1b\n" ".previous" : [old] "=&r"(old), [new] "=&r"(new), [c] "=&r"(c) : [mem] "m"(*v), [a] "rI"(a), [u] "rI"((long)u) : "memory"); smp_mb(); return old; } /** * 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 true iff @v was not @u. */ static __inline__ int atomic64_add_unless(atomic64_t *v, long a, long u) { long c, tmp; smp_mb(); __asm__ __volatile__( "1: ldq_l %[tmp],%[mem]\n" " cmpeq %[tmp],%[u],%[c]\n" " addq %[tmp],%[a],%[tmp]\n" " bne %[c],2f\n" " stq_c %[tmp],%[mem]\n" " beq %[tmp],3f\n" "2:\n" ".subsection 2\n" "3: br 1b\n" ".previous" : [tmp] "=&r"(tmp), [c] "=&r"(c) : [mem] "m"(*v), [a] "rI"(a), [u] "rI"(u) : "memory"); smp_mb(); return !c; } /* * atomic64_dec_if_positive - decrement by 1 if old value positive * @v: pointer of type atomic_t * * The function returns the old value of *v minus 1, even if * the atomic variable, v, was not decremented. */ static inline long atomic64_dec_if_positive(atomic64_t *v) { long old, tmp; smp_mb(); __asm__ __volatile__( "1: ldq_l %[old],%[mem]\n" " subq %[old],1,%[tmp]\n" " ble %[old],2f\n" " stq_c %[tmp],%[mem]\n" " beq %[tmp],3f\n" "2:\n" ".subsection 2\n" "3: br 1b\n" ".previous" : [old] "=&r"(old), [tmp] "=&r"(tmp) : [mem] "m"(*v) : "memory"); smp_mb(); return old - 1; } #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 */