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Date: Sun, 22 Feb 2015 09:20:52 +0000
To: freebsd-arm@freebsd.org
From: "meloun-miracle-cz (Michal Meloun)" <phabric-noreply@FreeBSD.org>
Subject: [Differential] [Commented On] D1833: Add memory barriers to buf_ring
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Thread-Topic: D1833: Add memory barriers to buf_ring
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meloun-miracle-cz added a comment.

First of all, I was wrong in the behavior of atomic operations on ARM. After yesterday’s long session on IRC with Ian and Andy, we concluded that pure (non atomic) store affects(clears)  state of exclusive monitor. So our implementation of atomics is fine on ARM. I apologize for my mistake, and, please, ignore everything about atomic_cmpset() in my previous message.

Back to your first question. I thought it only as a technical note (because misordered read occurs on br_ring[]). So, i'm fine with proposed patch. 
And again, sorry for noise. I certainly did not intend to be “destructive”.

REVISION DETAIL
  https://reviews.freebsd.org/D1833

To: zbb, kmacy, rpaulo, imp
Cc: meloun-miracle-cz, onwahe-gmail-com, andrew, ian, adrian, freebsd-arm