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Date: Mon, 23 Feb 2015 00:13:58 +0000
To: freebsd-arm@freebsd.org
From: "kmacy (Kip Macy)" <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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kmacy added a comment.

Reading this again, cons_head is used only by dequeue and is thus protected by the lock or an atomic update. Hence the atomic_load_acq_32 isn't needed for it. On the other hand, there are other places where prod_tail needs to be read with a memory barrier.

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

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