diff options
Diffstat (limited to 'arch/arc/include/asm/cmpxchg.h')
-rw-r--r-- | arch/arc/include/asm/cmpxchg.h | 23 |
1 files changed, 0 insertions, 23 deletions
diff --git a/arch/arc/include/asm/cmpxchg.h b/arch/arc/include/asm/cmpxchg.h index e2ae0eb1ca07..c5b544a5fe81 100644 --- a/arch/arc/include/asm/cmpxchg.h +++ b/arch/arc/include/asm/cmpxchg.h @@ -81,14 +81,6 @@ #endif /* - * atomic_cmpxchg is same as cmpxchg - * LLSC: only different in data-type, semantics are exactly same - * !LLSC: cmpxchg() has to use an external lock atomic_ops_lock to guarantee - * semantics, and this lock also happens to be used by atomic_*() - */ -#define arch_atomic_cmpxchg(v, o, n) ((int)arch_cmpxchg(&((v)->counter), (o), (n))) - -/* * xchg */ #ifdef CONFIG_ARC_HAS_LLSC @@ -148,19 +140,4 @@ #endif -/* - * "atomic" variant of xchg() - * REQ: It needs to follow the same serialization rules as other atomic_xxx() - * Since xchg() doesn't always do that, it would seem that following definition - * is incorrect. But here's the rationale: - * SMP : Even xchg() takes the atomic_ops_lock, so OK. - * LLSC: atomic_ops_lock are not relevant at all (even if SMP, since LLSC - * is natively "SMP safe", no serialization required). - * UP : other atomics disable IRQ, so no way a difft ctxt atomic_xchg() - * could clobber them. atomic_xchg() itself would be 1 insn, so it - * can't be clobbered by others. Thus no serialization required when - * atomic_xchg is involved. - */ -#define arch_atomic_xchg(v, new) (arch_xchg(&((v)->counter), new)) - #endif |