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Date: Tue, 22 Sep 2015 15:50:59 -0400
From: Tejun Heo <tj@kernel.org>
To: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Herbert Xu <herbert@gondor.apana.org.au>,
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Subject: Re: [PATCH v2] netlink: Replace rhash_portid with bound
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Hello,

On Tue, Sep 22, 2015 at 12:28:45PM -0700, Linus Torvalds wrote:
> Both acquire and smp_rmb() are equally free on x86.

Was this always like this?  Ah, okay, from 2007.  Was thinking it's
still doing an actual rmb.  Talk about being confused.

> It appears that we don't do the X86_PPRO_FENCE bug handling for
> acquire, but I guess we should.

Hmmm?  We're doing that.  PPRO_FENCE makes both acquire and release
use smp_mb().

Thanks.

-- 
tejun