From patchwork Wed Mar 3 14:46:50 2010 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mike Galbraith X-Patchwork-Id: 46813 X-Patchwork-Delegate: davem@davemloft.net Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 6DB52B7CB8 for ; Thu, 4 Mar 2010 01:47:23 +1100 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754740Ab0CCOqz (ORCPT ); Wed, 3 Mar 2010 09:46:55 -0500 Received: from mail.gmx.net ([213.165.64.20]:48825 "HELO mail.gmx.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1754658Ab0CCOqy (ORCPT ); Wed, 3 Mar 2010 09:46:54 -0500 Received: (qmail invoked by alias); 03 Mar 2010 14:46:52 -0000 Received: from p4FE1A7BA.dip0.t-ipconnect.de (EHLO [192.168.178.27]) [79.225.167.186] by mail.gmx.net (mp042) with SMTP; 03 Mar 2010 15:46:52 +0100 X-Authenticated: #14349625 X-Provags-ID: V01U2FsdGVkX1+V1Aou62aVfEaI6R9kbCUti3UHJ1yyz4OHlGTF7d QEGRncISBriMlW Subject: Re: [rfc/rft][patch] should use scheduler sync hint in tcp_prequeue()? From: Mike Galbraith To: David Miller Cc: eric.dumazet@gmail.com, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, mingo@elte.hu In-Reply-To: <20100303.060529.195713861.davem@davemloft.net> References: <1267522901.25906.101.camel@marge.simson.net> <1267529273.2964.111.camel@edumazet-laptop> <20100303.060529.195713861.davem@davemloft.net> Date: Wed, 03 Mar 2010 15:46:50 +0100 Message-Id: <1267627610.6264.21.camel@marge.simson.net> Mime-Version: 1.0 X-Mailer: Evolution 2.24.1.1 X-Y-GMX-Trusted: 0 X-FuHaFi: 0.46999999999999997 Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On Wed, 2010-03-03 at 06:05 -0800, David Miller wrote: > It definitely looks like an oversight to me and we should add > be using wake_up_interruptible_sync_poll() in tcp_prequeue() > as above. > > Ingo? Implied ack from network maintainer implies ship it to me. net: add scheduler sync hint to tcp_prequeue(). Decreases the odds wakee will suffer from frequent cache misses. Signed-off-by: Mike Galbraith Cc: David Miller LKML-Reference: --- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html diff --git a/include/net/tcp.h b/include/net/tcp.h index 34f5cc2..ba3fc64 100644 --- a/include/net/tcp.h +++ b/include/net/tcp.h @@ -939,7 +939,7 @@ static inline int tcp_prequeue(struct sock *sk, struct sk_buff *skb) tp->ucopy.memory = 0; } else if (skb_queue_len(&tp->ucopy.prequeue) == 1) { - wake_up_interruptible_poll(sk->sk_sleep, + wake_up_interruptible_sync_poll(sk->sk_sleep, POLLIN | POLLRDNORM | POLLRDBAND); if (!inet_csk_ack_scheduled(sk)) inet_csk_reset_xmit_timer(sk, ICSK_TIME_DACK,