From mboxrd@z Thu Jan  1 00:00:00 1970
From: "H. Peter Anvin" <hpa-YMNOUZJC4hwAvxtiuMwx3w@public.gmane.org>
Subject: Re: [PATCH v4 1/5] getcpu_cache system call: cache CPU number of running thread
Date: Mon, 29 Feb 2016 10:19:17 -0800
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On February 29, 2016 4:41:49 AM PST, Mathieu Desnoyers <mathieu.desnoyers-vg+e7yoeK/dWk0Htik3J/w@public.gmane.org> 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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