From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Miller Subject: Re: [PATCH net-next-2.6] net_sched: RCU conversion of stab Date: Thu, 20 Jan 2011 16:56:27 -0800 (PST) Message-ID: <20110120.165627.128607017.davem@davemloft.net> References: <1295517052.2733.14.camel@edumazet-laptop> <1295518636.2825.4.camel@edumazet-laptop> <1295531299.2825.175.camel@edumazet-laptop> Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org, kaber@trash.net, hawk@diku.dk, jarkao2@gmail.com, hadi@cyberus.ca To: eric.dumazet@gmail.com Return-path: Received: from 74-93-104-97-Washington.hfc.comcastbusiness.net ([74.93.104.97]:55280 "EHLO sunset.davemloft.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752518Ab1AUAzx (ORCPT ); Thu, 20 Jan 2011 19:55:53 -0500 In-Reply-To: <1295531299.2825.175.camel@edumazet-laptop> Sender: netdev-owner@vger.kernel.org List-ID: From: Eric Dumazet Date: Thu, 20 Jan 2011 14:48:19 +0100 > This patch converts stab qdisc management to RCU, so that we can perform > the qdisc_calculate_pkt_len() call before getting qdisc lock. > > This shortens the lock's held time in __dev_xmit_skb(). > > This permits more qdiscs to get TCQ_F_CAN_BYPASS status, avoiding lot of > cache misses and so reducing latencies. > > Signed-off-by: Eric Dumazet Applied.