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Date: Sun, 9 Feb 2014 16:56:26 -0800
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Subject: Re: [RFC][PATCH 0/5] arch: atomic rework
From: Linus Torvalds <torvalds@linux-foundation.org>
To: Torvald Riegel <triegel@redhat.com>
Cc: Paul McKenney <paulmck@linux.vnet.ibm.com>,
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On Sun, Feb 9, 2014 at 4:27 PM, Torvald Riegel <triegel@redhat.com> wrote:
>
> I wouldn't characterize the situation like this (although I can't speak
> for others, obviously).  IMHO, it's perfectly fine on sequential /
> non-synchronizing code, because we know the difference isn't observable
> by a correct program.

What BS is that? If you use an "atomic_store_explicit()", by
definition you're either

 (a) f*cking insane
 (b) not doing sequential non-synchronizing code

and a compiler that assumes that the programmer is insane may actually
be correct more often than not, but it's still a shit compiler.
Agreed?

So I don't see how any sane person can say that speculative writes are
ok. They are clearly not ok.

Speculative stores are a bad idea in general. They are completely
invalid for anything that says "atomic". This is not even worth
discussing.

                Linus