Quelle  atomic-llsc.h   Sprache: C

/* SPDX-License-Identifier: GPL-2.0-only */

#ifndef _ASM_ARC_ATOMIC_LLSC_H
#define _ASM_ARC_ATOMIC_LLSC_H

#define arch_atomic_set(v, i) WRITE_ONCE(((v)->counter), (i))

#define ATOMIC_OP(op, asm_op)     \
static inline void arch_atomic_##op(int i, atomic_t *v)   \
{         \
 unsigned int val;      \
         \
 __asm__ __volatile__(      \
 "1: llock %[val], [%[ctr]] \n"  \
 " " #asm_op " %[val], %[val], %[i] \n"  \
 " scond %[val], [%[ctr]] \n"  \
 " bnz 1b \n"  \
 : [val] "=&r" (val) /* Early clobber to prevent reg reuse */ \
 : [ctr] "r" (&v->counter), /* Not "m": llock only supports reg direct addr mode */ \
   [i] "ir" (i)      \
 : "cc", "memory");      \
}         \

#define ATOMIC_OP_RETURN(op, asm_op)    \
static inline int arch_atomic_##op##_return_relaxed(int i, atomic_t *v) \
{         \
 unsigned int val;      \
         \
 __asm__ __volatile__(      \
 "1: llock %[val], [%[ctr]] \n"  \
 " " #asm_op " %[val], %[val], %[i] \n"  \
 " scond %[val], [%[ctr]] \n"  \
 " bnz 1b \n"  \
 : [val] "=&r" (val)      \
 : [ctr] "r" (&v->counter),     \
   [i] "ir" (i)      \
 : "cc", "memory");      \
         \
 return val;       \
}

#define arch_atomic_add_return_relaxed  arch_atomic_add_return_relaxed
#define arch_atomic_sub_return_relaxed  arch_atomic_sub_return_relaxed

#define ATOMIC_FETCH_OP(op, asm_op)    \
static inline int arch_atomic_fetch_##op##_relaxed(int i, atomic_t *v) \
{         \
 unsigned int val, orig;      \
         \
 __asm__ __volatile__(      \
 "1: llock %[orig], [%[ctr]] \n"  \
 " " #asm_op " %[val], %[orig], %[i] \n"  \
 " scond %[val], [%[ctr]] \n"  \
 " bnz 1b \n"  \
 : [val] "=&r" (val),      \
   [orig] "=&r" (orig)      \
 : [ctr] "r" (&v->counter),     \
   [i] "ir" (i)      \
 : "cc", "memory");      \
         \
 return orig;       \
}

#define arch_atomic_fetch_add_relaxed  arch_atomic_fetch_add_relaxed
#define arch_atomic_fetch_sub_relaxed  arch_atomic_fetch_sub_relaxed

#define arch_atomic_fetch_and_relaxed  arch_atomic_fetch_and_relaxed
#define arch_atomic_fetch_andnot_relaxed arch_atomic_fetch_andnot_relaxed
#define arch_atomic_fetch_or_relaxed  arch_atomic_fetch_or_relaxed
#define arch_atomic_fetch_xor_relaxed  arch_atomic_fetch_xor_relaxed

#define ATOMIC_OPS(op, asm_op)     \
 ATOMIC_OP(op, asm_op)     \
 ATOMIC_OP_RETURN(op, asm_op)    \
 ATOMIC_FETCH_OP(op, asm_op)

ATOMIC_OPS(add, add)
ATOMIC_OPS(sub, sub)

#undef ATOMIC_OPS
#define ATOMIC_OPS(op, asm_op)     \
 ATOMIC_OP(op, asm_op)     \
 ATOMIC_FETCH_OP(op, asm_op)

ATOMIC_OPS(and, and)
ATOMIC_OPS(andnot, bic)
ATOMIC_OPS(or, or)
ATOMIC_OPS(xor, xor)

#define arch_atomic_andnot  arch_atomic_andnot

#undef ATOMIC_OPS
#undef ATOMIC_FETCH_OP
#undef ATOMIC_OP_RETURN
#undef ATOMIC_OP

#endif