Messages in this thread | | | Date | Tue, 14 Jan 2014 12:03:07 +0100 | From | Peter Zijlstra <> | Subject | Re: [PATCH v8 4/4] qrwlock: Use smp_store_release() in write_unlock() |
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On Tue, Jan 14, 2014 at 10:28:23AM +0800, Daniel J Blueman wrote: > >Peter, > > > >I found out that the build failure was caused by the fact that the > >__native_word() macro (used internally by compiletime_assert_atomic()) > >allows only a size of 4 or 8 for x86-64. The data type that I used is a > >byte. Is there a reason why byte and short are not considered native? > > It seems likely it was implemented like that since there was no existing > need; long can be relied on as the largest native type, so this should > suffice and works here:
There's Alphas that cannot actually atomically adres a byte; I do not konw if Linux cares about them, but if it does, we cannot in fact rely on this in generic primitives like this.
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