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Re: mips octeon memory model questions

To: Peter Zijlstra <peterz@infradead.org>
Subject: Re: mips octeon memory model questions
From: Linus Torvalds <torvalds@linux-foundation.org>
Date: Tue, 4 Feb 2014 10:58:40 -0800
Cc: David Daney <ddaney@caviumnetworks.com>, Ralf Baechle <ralf@linux-mips.org>, "linux-arch@vger.kernel.org" <linux-arch@vger.kernel.org>, linux-mips <linux-mips@linux-mips.org>, Linux Kernel Mailing List <linux-kernel@vger.kernel.org>, Paul McKenney <paulmck@linux.vnet.ibm.com>, Will Deacon <will.deacon@arm.com>
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On Tue, Feb 4, 2014 at 10:41 AM, Peter Zijlstra <peterz@infradead.org> wrote:
>
> Still doesn't make sense, because if we need the first sync to stop
> writes from being re-ordered with the ll-sc, we also need the second
> sync to avoid the same.

Presumably octeon doesn't do speculative writes, only *buffered* writes.

So writes move down, not up.

But it looks like Cavium is one of those clown companies that have a
"contact us" button for technical documentation rather than actually
making it available.

Christ, why would anybody do business with a tech company that hides
technical details? Seriously, that just stinks of "we have so many
bugs that we cannot make the documentation available".

                  Linus

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