From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jarek Poplawski Subject: Re: [PATCHv4 2/2] memory barrier: adding smp_mb__after_lock Date: Fri, 3 Jul 2009 07:47:31 +0000 Message-ID: <20090703074730.GB4847@ff.dom.local> References: <20090702063259.GA3429@jolsa.lab.eng.brq.redhat.com> <20090702063624.GC3429@jolsa.lab.eng.brq.redhat.com> <4A4C5983.7000501@gmail.com> <20090703074126.GB2902@jolsa.lab.eng.brq.redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: QUOTED-PRINTABLE Cc: Davide Libenzi , Eric Dumazet , netdev@vger.kernel.org, Linux Kernel Mailing List , fbl@redhat.com, nhorman@redhat.com, davem@redhat.com, htejun@gmail.com, oleg@redhat.com To: Jiri Olsa Return-path: Received: from mail-fx0-f218.google.com ([209.85.220.218]:52797 "EHLO mail-fx0-f218.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750799AbZGCHre (ORCPT ); Fri, 3 Jul 2009 03:47:34 -0400 Content-Disposition: inline In-Reply-To: <20090703074126.GB2902@jolsa.lab.eng.brq.redhat.com> Sender: netdev-owner@vger.kernel.org List-ID: On Fri, Jul 03, 2009 at 09:41:26AM +0200, Jiri Olsa wrote: > On Thu, Jul 02, 2009 at 07:39:04AM -0700, Davide Libenzi wrote: > > On Thu, 2 Jul 2009, Eric Dumazet wrote: > >=20 > > > Jiri Olsa a =E9crit : > > > > Adding smp_mb__after_lock define to be used as a smp_mb call af= ter > > > > a lock. =20 > > > >=20 > > > > Making it nop for x86, since {read|write|spin}_lock() on x86 ar= e=20 > > > > full memory barriers. > > > >=20 > > > > wbr, > > > > jirka > > > >=20 > > > >=20 > > > > Signed-off-by: Jiri Olsa > > >=20 > > >=20 > > > Maybe we should remind that sk_has_helper() is always called > > > right after a call to read_lock() as in : > > >=20 > > > read_lock(&sk->sk_callback_lock); > > > if (sk_has_sleeper(sk)) > > > wake_up_interruptible_all(sk->sk_sleep); > >=20 > > Agreed, that'd be to have it in the source code comment. > >=20 > >=20 > > - Davide > >=20 >=20 > ok, I'll add it to the 1/2 part in v5 >=20 Btw., there is a tiny typo: - receive callbacks. Adding fuctions sock_poll_wait and sock_has_sleepe= r + receive callbacks. Adding fuctions sock_poll_wait and sk_has_sleeper Jarek P.