/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _ASM_X86_ATOMIC64_32_H
#define _ASM_X86_ATOMIC64_32_H
#include <linux/compiler.h>
#include <linux/types.h>
//#include <asm/cmpxchg.h>
/* An 64bit atomic type */
typedef struct {
s64 __aligned(8) counter;
} atomic64_t;
#define ATOMIC64_INIT(val) { (val) }
/*
* Read an atomic64_t non-atomically.
*
* This is intended to be used in cases where a subsequent atomic operation
* will handle the torn value, and can be used to prime the first iteration
* of unconditional try_cmpxchg() loops, e.g.:
*
* s64 val = arch_atomic64_read_nonatomic(v);
* do { } while (!arch_atomic64_try_cmpxchg(v, &val, val OP i);
*
* This is NOT safe to use where the value is not always checked by a
* subsequent atomic operation, such as in conditional try_cmpxchg() loops
* that can break before the atomic operation, e.g.:
*
* s64 val = arch_atomic64_read_nonatomic(v);
* do {
* if (condition(val))
* break;
* } while (!arch_atomic64_try_cmpxchg(v, &val, val OP i);
*/
static __always_inline s64 arch_atomic64_read_nonatomic(const atomic64_t *v)
{
/* See comment in arch_atomic_read(). */
return __READ_ONCE(v->counter);
}
#define __ATOMIC64_DECL(sym) void atomic64_##sym(atomic64_t *, ...)
#ifndef ATOMIC64_EXPORT
#define ATOMIC64_DECL_ONE __ATOMIC64_DECL
#else
#define ATOMIC64_DECL_ONE(sym) __ATOMIC64_DECL(sym); \
ATOMIC64_EXPORT(atomic64_##sym)
#endif
#ifdef CONFIG_X86_CMPXCHG64
#define __alternative_atomic64(f, g, out, in...) \
asm volatile("call %c[func]" \
: out : [func] "i" (atomic64_##g##_cx8), ## in)
#define ATOMIC64_DECL(sym) ATOMIC64_DECL_ONE(sym##_cx8)
#else
#define __alternative_atomic64(f, g, out, in...) \
alternative_call(atomic64_##f##_386, atomic64_##g##_cx8, \
X86_FEATURE_CX8, ASM_OUTPUT2(out), ## in)
#define ATOMIC64_DECL(sym) ATOMIC64_DECL_ONE(sym##_cx8); \
ATOMIC64_DECL_ONE(sym##_386)
ATOMIC64_DECL_ONE(add_386);
ATOMIC64_DECL_ONE(sub_386);
ATOMIC64_DECL_ONE(inc_386);
ATOMIC64_DECL_ONE(dec_386);
#endif
#define alternative_atomic64(f, out, in...) \
__alternative_atomic64(f, f, ASM_OUTPUT2(out), ## in)
ATOMIC64_DECL(read);
ATOMIC64_DECL(set);
ATOMIC64_DECL(xchg);
ATOMIC64_DECL(add_return);
ATOMIC64_DECL(sub_return);
ATOMIC64_DECL(inc_return);
ATOMIC64_DECL(dec_return);
ATOMIC64_DECL(dec_if_positive);
ATOMIC64_DECL(inc_not_zero);
ATOMIC64_DECL(add_unless);
#undef ATOMIC64_DECL
#undef ATOMIC64_DECL_ONE
#undef __ATOMIC64_DECL
#undef ATOMIC64_EXPORT
static __always_inline s64 arch_atomic64_cmpxchg(atomic64_t *v, s64 old, s64 new)
{
return arch_cmpxchg64(&v->counter, old, new);
}
#define arch_atomic64_cmpxchg arch_atomic64_cmpxchg
static __always_inline bool arch_atomic64_try_cmpxchg(atomic64_t *v, s64 *old, s64 new)
{
return arch_try_cmpxchg64(&v->counter, old, new);
}
#define arch_atomic64_try_cmpxchg arch_atomic64_try_cmpxchg
static __always_inline s64 arch_atomic64_xchg(atomic64_t *v, s64 n)
{
s64 o;
unsigned high = (unsigned)(n >> 32);
unsigned low = (unsigned)n;
alternative_atomic64(xchg, "=&A" (o),
"S" (v), "b" (low), "c" (high)
: "memory");
return o;
}
#define arch_atomic64_xchg arch_atomic64_xchg
static __always_inline void arch_atomic64_set(atomic64_t *v, s64 i)
{
unsigned high = (unsigned)(i >> 32);
unsigned low = (unsigned)i;
alternative_atomic64(set, /* no output */,
"S" (v), "b" (low), "c" (high)
: "eax", "edx", "memory");
}
static __always_inline s64 arch_atomic64_read(const atomic64_t *v)
{
s64 r;
alternative_atomic64(read, "=&A" (r), "c" (v) : "memory");
return r;
}
static __always_inline s64 arch_atomic64_add_return(s64 i, atomic64_t *v)
{
alternative_atomic64(add_return,
ASM_OUTPUT2("+A" (i), "+c" (v)),
ASM_NO_INPUT_CLOBBER("memory"));
return i;
}
#define arch_atomic64_add_return arch_atomic64_add_return
static __always_inline s64 arch_atomic64_sub_return(s64 i, atomic64_t *v)
{
alternative_atomic64(sub_return,
ASM_OUTPUT2("+A" (i), "+c" (v)),
ASM_NO_INPUT_CLOBBER("memory"));
return i;
}
#define arch_atomic64_sub_return arch_atomic64_sub_return
static __always_inline s64 arch_atomic64_inc_return(atomic64_t *v)
{
s64 a;
alternative_atomic64(inc_return, "=&A" (a),
"S" (v) : "memory", "ecx");
return a;
}
#define arch_atomic64_inc_return arch_atomic64_inc_return
static __always_inline s64 arch_atomic64_dec_return(atomic64_t *v)
{
s64 a;
alternative_atomic64(dec_return, "=&A" (a),
"S" (v) : "memory", "ecx");
return a;
}
#define arch_atomic64_dec_return arch_atomic64_dec_return
static __always_inline s64 arch_atomic64_add(s64 i, atomic64_t *v)
{
__alternative_atomic64(add, add_return,
ASM_OUTPUT2("+A" (i), "+c" (v)),
ASM_NO_INPUT_CLOBBER("memory"));
return i;
}
static __always_inline s64 arch_atomic64_sub(s64 i, atomic64_t *v)
{
__alternative_atomic64(sub, sub_return,
ASM_OUTPUT2("+A" (i), "+c" (v)),
ASM_NO_INPUT_CLOBBER("memory"));
return i;
}
static __always_inline void arch_atomic64_inc(atomic64_t *v)
{
__alternative_atomic64(inc, inc_return, /* no output */,
"S" (v) : "memory", "eax", "ecx", "edx");
}
#define arch_atomic64_inc arch_atomic64_inc
static __always_inline void arch_atomic64_dec(atomic64_t *v)
{
__alternative_atomic64(dec, dec_return, /* no output */,
"S" (v) : "memory", "eax", "ecx", "edx");
}
#define arch_atomic64_dec arch_atomic64_dec
static __always_inline int arch_atomic64_add_unless(atomic64_t *v, s64 a, s64 u)
{
unsigned low = (unsigned)u;
unsigned high = (unsigned)(u >> 32);
alternative_atomic64(add_unless,
ASM_OUTPUT2("+A" (a), "+c" (low), "+D" (high)),
"S" (v) : "memory");
return (int)a;
}
#define arch_atomic64_add_unless arch_atomic64_add_unless
static __always_inline int arch_atomic64_inc_not_zero(atomic64_t *v)
{
int r;
alternative_atomic64(inc_not_zero, "=&a" (r),
"S" (v) : "ecx", "edx", "memory");
return r;
}
#define arch_atomic64_inc_not_zero arch_atomic64_inc_not_zero
static __always_inline s64 arch_atomic64_dec_if_positive(atomic64_t *v)
{
s64 r;
alternative_atomic64(dec_if_positive, "=&A" (r),
"S" (v) : "ecx", "memory");
return r;
}
#define arch_atomic64_dec_if_positive arch_atomic64_dec_if_positive
#undef alternative_atomic64
#undef __alternative_atomic64
static __always_inline void arch_atomic64_and(s64 i, atomic64_t *v)
{
s64 val = arch_atomic64_read_nonatomic(v);
do { } while (!arch_atomic64_try_cmpxchg(v, &val, val & i));
}
static __always_inline s64 arch_atomic64_fetch_and(s64 i, atomic64_t *v)
{
s64 val = arch_atomic64_read_nonatomic(v);
do { } while (!arch_atomic64_try_cmpxchg(v, &val, val & i));
return val;
}
#define arch_atomic64_fetch_and arch_atomic64_fetch_and
static __always_inline void arch_atomic64_or(s64 i, atomic64_t *v)
{
s64 val = arch_atomic64_read_nonatomic(v);
do { } while (!arch_atomic64_try_cmpxchg(v, &val, val | i));
}
static __always_inline s64 arch_atomic64_fetch_or(s64 i, atomic64_t *v)
{
s64 val = arch_atomic64_read_nonatomic(v);
do { } while (!arch_atomic64_try_cmpxchg(v, &val, val | i));
return val;
}
#define arch_atomic64_fetch_or arch_atomic64_fetch_or
static __always_inline void arch_atomic64_xor(s64 i, atomic64_t *v)
{
s64 val = arch_atomic64_read_nonatomic(v);
do { } while (!arch_atomic64_try_cmpxchg(v, &val, val ^ i));
}
static __always_inline s64 arch_atomic64_fetch_xor(s64 i, atomic64_t *v)
{
s64 val = arch_atomic64_read_nonatomic(v);
do { } while (!arch_atomic64_try_cmpxchg(v, &val, val ^ i));
return val;
}
#define arch_atomic64_fetch_xor arch_atomic64_fetch_xor
static __always_inline s64 arch_atomic64_fetch_add(s64 i, atomic64_t *v)
{
s64 val = arch_atomic64_read_nonatomic(v);
do { } while (!arch_atomic64_try_cmpxchg(v, &val, val + i));
return val;
}
#define arch_atomic64_fetch_add arch_atomic64_fetch_add
#define arch_atomic64_fetch_sub(i, v) arch_atomic64_fetch_add(-(i), (v))
#endif /* _ASM_X86_ATOMIC64_32_H */
Codebase Browser
linux