diff options
| -rw-r--r-- | lf_cas.h | 95 |
1 files changed, 67 insertions, 28 deletions
@@ -1,7 +1,7 @@ /* * File : lf_cas.h * Author : Jérémy Zurcher <jeremy@asynk.ch> - * Date : 01/11/09 + * Date : 2009/11/01 * License : * * Permission is hereby granted, free of charge, to any person obtaining @@ -11,10 +11,10 @@ * distribute, sublicense, and/or sell copies of the Software, and to * permit persons to whom the Software is furnished to do so, subject to * the following conditions: - * + * * The above copyright notice and this permission notice shall be * included in all copies or substantial portions of the Software. - * + * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND @@ -32,31 +32,70 @@ extern "C" { # endif /* __cplusplus */ -struct lf_pointer; - -typedef struct lf_pointer { - volatile struct lf_pointer *ptr; - volatile unsigned int count; -} lf_pointer_t; - -union ptr_u { - lf_pointer_t ptr; - volatile long long concat; -}; - -#define lf_eql(ptra,ptrb) (((union ptr_u)(ptra)).concat == ((union ptr_u)(ptrb)).concat) - -/* CMPXCHG8B m64 Compare EDX:EAX with m64. If equal, set ZF and load ECX:EBX into m64. Else, clear ZF and load m64 into EDX:EAX. */ -static inline unsigned int cas( volatile lf_pointer_t *mem, - volatile lf_pointer_t old, - volatile lf_pointer_t new ) { - char result; - __asm__ __volatile__("lock; cmpxchg8b %0; setz %1;" - : "=m"(*mem), "=q"(result) - : "m"(*mem), "d" (old.count), "a" (old.ptr), - "c" (new.count), "b" (new.ptr) - : "memory"); - return (int)result; +#include <stdint.h> + +#if defined(__i386__) && defined(__GNUC__) + +#define _cas_field_t uint32_t +#define _cas_aligned 8 + +#elif defined(__x86_64__) && defined(__GNUC__) + +#define _cas_field_t uint64_t +#define _cas_aligned 16 + +#else +#error "cas not implemented yet for your arch" +#endif + +struct _lf_pointer_t +{ + _cas_field_t pointer; + _cas_field_t counter; +} __attribute__ (( __aligned__( _cas_aligned ) )); + +typedef struct _lf_pointer_t lf_pointer_t; + +#define lf_counter_set(p,v) ((p).counter=(_cas_field_t)(v)) +#define lf_pointer_set(p,v) ((p).pointer=(_cas_field_t)(v)) +#define lf_eq(p0,p1) ((p0).pointer==(p1).pointer && (p0).counter==(p1).counter) +#define lf_pointer_null(p) ((p).pointer==(_cas_field_t)NULL) + +static inline int lf_cas(volatile lf_pointer_t* mem, lf_pointer_t old_val, lf_pointer_t new_val) +{ + char success; + +#if defined(__i386__) && defined(__GNUC__) + + asm volatile("lock cmpxchg8b (%6);" + "setz %7;" + : "=a" ( old_val.pointer ) + , "=d" ( old_val.counter ) + : "0" ( old_val.pointer ) + , "1" ( old_val.counter ) + , "b" ( new_val.pointer ) + , "c" ( new_val.counter ) + , "r" ( mem ) + , "m" ( success ) + : "cc", "memory" + ); + +#elif defined(__x86_64__) && defined(__GNUC__) + + asm volatile ( + "lock cmpxchg16b %1;" + "setz %0;" + : "=q" ( success ) + , "+m" ( *mem ) + , "+d" ( old_val.counter ) + , "+a" ( old_val.pointer ) + : "c" ( new_val.counter ) + , "b" ( new_val.pointer ) + : "cc", "memory" + ); +#endif + + return (int)success; } # ifdef __cplusplus |