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- /* SPDX-License-Identifier: GPL-2.0-only */
- #ifndef _ASM_ARC_ATOMIC_SPLOCK_H
- #define _ASM_ARC_ATOMIC_SPLOCK_H
- /*
- * Non hardware assisted Atomic-R-M-W
- * Locking would change to irq-disabling only (UP) and spinlocks (SMP)
- */
- static inline void arch_atomic_set(atomic_t *v, int i)
- {
- /*
- * Independent of hardware support, all of the atomic_xxx() APIs need
- * to follow the same locking rules to make sure that a "hardware"
- * atomic insn (e.g. LD) doesn't clobber an "emulated" atomic insn
- * sequence
- *
- * Thus atomic_set() despite being 1 insn (and seemingly atomic)
- * requires the locking.
- */
- unsigned long flags;
- atomic_ops_lock(flags);
- WRITE_ONCE(v->counter, i);
- atomic_ops_unlock(flags);
- }
- #define arch_atomic_set_release(v, i) arch_atomic_set((v), (i))
- #define ATOMIC_OP(op, c_op, asm_op) \
- static inline void arch_atomic_##op(int i, atomic_t *v) \
- { \
- unsigned long flags; \
- \
- atomic_ops_lock(flags); \
- v->counter c_op i; \
- atomic_ops_unlock(flags); \
- }
- #define ATOMIC_OP_RETURN(op, c_op, asm_op) \
- static inline int arch_atomic_##op##_return(int i, atomic_t *v) \
- { \
- unsigned long flags; \
- unsigned int temp; \
- \
- /* \
- * spin lock/unlock provides the needed smp_mb() before/after \
- */ \
- atomic_ops_lock(flags); \
- temp = v->counter; \
- temp c_op i; \
- v->counter = temp; \
- atomic_ops_unlock(flags); \
- \
- return temp; \
- }
- #define ATOMIC_FETCH_OP(op, c_op, asm_op) \
- static inline int arch_atomic_fetch_##op(int i, atomic_t *v) \
- { \
- unsigned long flags; \
- unsigned int orig; \
- \
- /* \
- * spin lock/unlock provides the needed smp_mb() before/after \
- */ \
- atomic_ops_lock(flags); \
- orig = v->counter; \
- v->counter c_op i; \
- atomic_ops_unlock(flags); \
- \
- return orig; \
- }
- #define ATOMIC_OPS(op, c_op, asm_op) \
- ATOMIC_OP(op, c_op, asm_op) \
- ATOMIC_OP_RETURN(op, c_op, asm_op) \
- ATOMIC_FETCH_OP(op, c_op, asm_op)
- ATOMIC_OPS(add, +=, add)
- ATOMIC_OPS(sub, -=, sub)
- #undef ATOMIC_OPS
- #define ATOMIC_OPS(op, c_op, asm_op) \
- ATOMIC_OP(op, c_op, asm_op) \
- ATOMIC_FETCH_OP(op, c_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
- #define arch_atomic_fetch_andnot arch_atomic_fetch_andnot
- #undef ATOMIC_OPS
- #undef ATOMIC_FETCH_OP
- #undef ATOMIC_OP_RETURN
- #undef ATOMIC_OP
- #endif
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