From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Miller Subject: Re: [PATCH net-next-2.6] phonet: use call_rcu for phonet device free Date: Wed, 09 Jun 2010 16:15:07 -0700 (PDT) Message-ID: <20100609.161507.226788333.davem@davemloft.net> References: <20100607132738.GB2730@psychotron.lab.eng.brq.redhat.com> <474f08fed4a406e929af3d4142d3e185@chewa.net> <1275918583.2545.84.camel@edumazet-laptop> Mime-Version: 1.0 Content-Type: Text/Plain; charset=iso-8859-1 Content-Transfer-Encoding: QUOTED-PRINTABLE Cc: remi@remlab.net, jpirko@redhat.com, netdev@vger.kernel.org To: eric.dumazet@gmail.com Return-path: Received: from 74-93-104-97-Washington.hfc.comcastbusiness.net ([74.93.104.97]:33596 "EHLO sunset.davemloft.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752348Ab0FIXO4 convert rfc822-to-8bit (ORCPT ); Wed, 9 Jun 2010 19:14:56 -0400 In-Reply-To: <1275918583.2545.84.camel@edumazet-laptop> Sender: netdev-owner@vger.kernel.org List-ID: =46rom: Eric Dumazet Date: Mon, 07 Jun 2010 15:49:43 +0200 > Le lundi 07 juin 2010 =E0 15:43 +0200, R=E9mi Denis-Courmont a =E9cri= t : >> On Mon, 7 Jun 2010 15:27:39 +0200, Jiri Pirko wr= ote: >> > Use call_rcu rather than synchronize_rcu. >> >=20 >> > Signed-off-by: Jiri Pirko >>=20 >> This looks fine to me, but what is the goal here? The RCU documentat= ion >> seems to imply that synchronize_rcu() is preferable over call_rcu() = when at >> all possible. >>=20 >=20 > Thats not exactly that. >=20 > synchronize_rcu() is easier, in respect of memory use. > But its drawback is current thread is blocked for several milli secon= ds. >=20 > In the end, call_rcu() is more scalable. >=20 > Acked-by: Eric Dumazet Applied, thanks.