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SubjectRe: [cpuops cmpxchg double V2 1/4] Gen eric support for this cpu cmpxchg double
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Don't apply "packed" to a structure which needs padding!  That's just user error.

"Mathieu Desnoyers" <mathieu.desnoyers@efficios.com> wrote:

>* Tejun Heo (tj@kernel.org) wrote:
>[...]
>> > (note: packed here along with "aligned" does _not_ generate ugly
>> > bytewise read/write memory ops like "packed" alone. The use of
>> > "packed" is to let the compiler down-align the structure to the
>> > value requested, instead of uselessly aligning it on 32-byte if it
>> > chooses to.)
>>
>> Yeah, good point. :-)
>
>For the records, I just noticed that "packed, aligned(8)" can generate
>unaligned
>accesses on sparc64 by removing the padding between a "int" and a
>following
>pointer. So we should not use it.
>
>Thanks,
>
>Mathieu
>
>--
>Mathieu Desnoyers
>Operating System Efficiency R&D Consultant
>EfficiOS Inc.
>http://www.efficios.com

--
Sent from my mobile phone. Please pardon any lack of formatting.


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