diff options
author | H. Peter Anvin <hpa@zytor.com> | 2008-09-04 08:08:42 -0700 |
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committer | H. Peter Anvin <hpa@zytor.com> | 2008-09-04 08:08:42 -0700 |
commit | 7203781c98ad9147564d327de6f6513ad8fc0f4e (patch) | |
tree | 5c29a2a04a626bf08a0d56fd8a0068b3c92ad284 /arch/alpha/include/asm/atomic.h | |
parent | 671eef85a3e885dff4ce210d8774ad50a91d5967 (diff) | |
parent | af2e1f276ff08f17192411ea3b71c13a758dfe12 (diff) |
Merge branch 'x86/cpu' into x86/core
Conflicts:
arch/x86/kernel/cpu/feature_names.c
include/asm-x86/cpufeature.h
Diffstat (limited to 'arch/alpha/include/asm/atomic.h')
-rw-r--r-- | arch/alpha/include/asm/atomic.h | 267 |
1 files changed, 267 insertions, 0 deletions
diff --git a/arch/alpha/include/asm/atomic.h b/arch/alpha/include/asm/atomic.h new file mode 100644 index 00000000000..ca88e54dec9 --- /dev/null +++ b/arch/alpha/include/asm/atomic.h @@ -0,0 +1,267 @@ +#ifndef _ALPHA_ATOMIC_H +#define _ALPHA_ATOMIC_H + +#include <asm/barrier.h> +#include <asm/system.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. + */ + + +/* + * Counter is volatile to make sure gcc doesn't try to be clever + * and move things around on us. We need to use _exactly_ the address + * the user gave us, not some alias that contains the same information. + */ +typedef struct { volatile int counter; } atomic_t; +typedef struct { volatile long counter; } atomic64_t; + +#define ATOMIC_INIT(i) ( (atomic_t) { (i) } ) +#define ATOMIC64_INIT(i) ( (atomic64_t) { (i) } ) + +#define atomic_read(v) ((v)->counter + 0) +#define atomic64_read(v) ((v)->counter + 0) + +#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 non-zero if @v was not @u, and zero otherwise. + */ +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) + +/** + * 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 non-zero if @v was not @u, and zero otherwise. + */ +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() + +#include <asm-generic/atomic.h> +#endif /* _ALPHA_ATOMIC_H */ |