Messages in this thread | | | Date | 1 Dec 2006 00:23:54 +0100 | Date | Fri, 1 Dec 2006 00:23:54 +0100 | From | Andi Kleen <> | Subject | Re: [PATCH] atomic_cmpxchg return type error |
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On Thu, Nov 30, 2006 at 04:17:06PM -0500, Mathieu Desnoyers wrote: > Hi, > > I just noticed that a atomic_cmpxchg, that would be given an atomic64_t > parameter, would cast the return value as a (int). In the typical use of this > primitive, the result would be that the 32 MSB would be lost when comparing > against the original value. It also affects atomic_add_unless. Note that there > is no atomic64_cmpxchg nor atomic64_add_unless, which might make things a > little clearer.
Normally you're supposed to only use atomic64_* with atomic64_t
While it works for most by accident on x86 to just use atomic_* with atomic64_t it's not portable to other architectures.
If you want to use those with atomic64_t suitable macros would need to be added on all architectures.
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