From 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Sat, 16 Apr 2005 15:20:36 -0700 Subject: Linux-2.6.12-rc2 Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip! --- include/asm-alpha/atomic.h | 198 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 198 insertions(+) create mode 100644 include/asm-alpha/atomic.h (limited to 'include/asm-alpha/atomic.h') diff --git a/include/asm-alpha/atomic.h b/include/asm-alpha/atomic.h new file mode 100644 index 00000000000..1b383e3cb68 --- /dev/null +++ b/include/asm-alpha/atomic.h @@ -0,0 +1,198 @@ +#ifndef _ALPHA_ATOMIC_H +#define _ALPHA_ATOMIC_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__ long atomic_add_return(int i, atomic_t * v) +{ + long temp, result; + __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" + " mb\n" + ".subsection 2\n" + "2: br 1b\n" + ".previous" + :"=&r" (temp), "=m" (v->counter), "=&r" (result) + :"Ir" (i), "m" (v->counter) : "memory"); + return result; +} + +#define atomic_add_negative(a, v) (atomic_add_return((a), (v)) < 0) + +static __inline__ long atomic64_add_return(long i, atomic64_t * v) +{ + long temp, result; + __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" + " mb\n" + ".subsection 2\n" + "2: br 1b\n" + ".previous" + :"=&r" (temp), "=m" (v->counter), "=&r" (result) + :"Ir" (i), "m" (v->counter) : "memory"); + return result; +} + +static __inline__ long atomic_sub_return(int i, atomic_t * v) +{ + long temp, result; + __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" + " mb\n" + ".subsection 2\n" + "2: br 1b\n" + ".previous" + :"=&r" (temp), "=m" (v->counter), "=&r" (result) + :"Ir" (i), "m" (v->counter) : "memory"); + return result; +} + +static __inline__ long atomic64_sub_return(long i, atomic64_t * v) +{ + long temp, result; + __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" + " mb\n" + ".subsection 2\n" + "2: br 1b\n" + ".previous" + :"=&r" (temp), "=m" (v->counter), "=&r" (result) + :"Ir" (i), "m" (v->counter) : "memory"); + return result; +} + +#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 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 */ -- cgit