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From: John Baldwin <jhb@freebsd.org>
To: Ian Lepore <ian@freebsd.org>
Subject: Re: atomic ops
Date: Wed, 29 Oct 2014 14:13:18 -0400
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Cc: Adrian Chadd <adrian@freebsd.org>, Mateusz Guzik <mjguzik@gmail.com>,
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On Wednesday, October 29, 2014 2:03:50 pm Ian Lepore wrote:
> I hadn't realized it when I wrote that, but Andy was speaking in the
> context of armv8, which has a true load-acquire instruction.  In our
> current code (armv6 and 7) we need the explicit dmb/dsb barriers to get
> the same effect.  (It turns out we do have barriers, I misspoke earlier,
> but some of our dmb need to be dsb.)

Ah, ok.  Fair enough. :)

-- 
John Baldwin