Re: [PATCH v4 1/5] getcpu_cache system call: cache CPU number of running thread

On February 29, 2016 4:41:49 AM PST, Mathieu Desnoyers [off-list ref] wrote:

Agreed that many architectures issue slower instructions when reading
from packed structures, which is unwanted.

And detrimental to atomicity.

Could we require that each field be naturally aligned and require that
they are placed so _no_ padding whatsoever should ever be added by the
compiler ? If that's possible, then we could remove the packed.

What people have been trying to tell you is that we *must* do this, and no compiler truck like packed will help.


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