From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jarek Poplawski <jarkao2@gmail.com>
Subject: Re: [PATCH net-next-2.6] net: inet_add_protocol() can use cmpxchg()
Date: Thu, 9 Sep 2010 09:08:17 +0000
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Cc: David Miller <davem@davemloft.net>, jesse@nicira.com,
	netdev@vger.kernel.org
To: Eric Dumazet <eric.dumazet@gmail.com>
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On Thu, Sep 09, 2010 at 07:24:53AM +0000, Jarek Poplawski wrote:
> On Thu, Sep 09, 2010 at 07:09:26AM +0000, Jarek Poplawski wrote:
> > On Thu, Sep 09, 2010 at 08:55:45AM +0200, Eric Dumazet wrote:
> > > Le jeudi 09 septembre 2010 ?? 06:42 +0000, Jarek Poplawski a =E9c=
rit :
> > > > Of course, each case is different, but generally I understand J=
esse's
> > > > concern. Smaller data section argument shouldn't be enough. The=
re is
> > > > some reason we do it in C not asm, and there is some cost of
> > > > unreadable code too.
> > >=20
> > > Sure, but is cmpxchg() really not readable for you ? ;)
> >=20
> > Just like for Jesse: "this takes a little more thought". ;-)
>=20
> But more exactly, it's not about this one line, but the time you need
> when reading this after some time to tell: yes, this place is properl=
y
> locked for sure.

And most exactly, without "after some time" I couldn't tell this
either. Is seems some barriers might have been changed, but I might
be wrong. Anyway, it would be nice to have some comment on that in
the changelog.

Jarek P.