From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: [RFC] use smp_load_acquire()/smp_store_release()
Date: Wed, 29 Oct 2014 07:49:19 -0700
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Cc: netdev <netdev@vger.kernel.org>,
	Stephen Ko <stephen.s.ko@intel.com>
To: Alexander Duyck <alexander.h.duyck@redhat.com>
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Hi Alexander

The memory barriers added in commit
b37c0fbe3f6dfba1f8ad2aed47fb40578a254635
("net: Add memory barriers to prevent possible race in byte queue
limits")

have heavy cost.

It seems we could use smp_load_acquire() and smp_store_release()
instead ?

I'll post a patch later today. I would be interested if someone was able
to test it, as your commit apparently was tested and known to fix a
reproducible race.

Thanks !