From patchwork Wed Sep 8 18:44:29 2010 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Eric Dumazet X-Patchwork-Id: 64194 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 0D996B6EEB for ; Thu, 9 Sep 2010 04:44:39 +1000 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752780Ab0IHSof (ORCPT ); Wed, 8 Sep 2010 14:44:35 -0400 Received: from mail-fx0-f46.google.com ([209.85.161.46]:58952 "EHLO mail-fx0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752122Ab0IHSoe (ORCPT ); Wed, 8 Sep 2010 14:44:34 -0400 Received: by fxm16 with SMTP id 16so344283fxm.19 for ; Wed, 08 Sep 2010 11:44:33 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:received:received:subject:from:to:cc :in-reply-to:references:content-type:date:message-id:mime-version :x-mailer:content-transfer-encoding; bh=1VfNnDP4+wp0eQRi5mg0DVJ7MZS6Hd/+i3jcj93UOTA=; b=fVOsg+FcLJuX4QkZzml1HiW8J2cl8ZWXVKSLNakdOV9lIAPe3W9lQnHeaoSMlFhu8Y 6a9GN15wak7b95tqP4YTiBo9cPCdIeL3xni4nKrdnUq8qEtn2ovxFBMvwvSB5HnsW3/b ULiwQ+KbN4OH8nfm/pbZog3e7HzzhdNmweJpE= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=subject:from:to:cc:in-reply-to:references:content-type:date :message-id:mime-version:x-mailer:content-transfer-encoding; b=exPaPWOWMqtXtk2tfd2F7Y+ZrMMYmA5yas4SGSjRDJnggiLKbq7RjioWVJQuOEIVNk /jiuEZcfEZucLF1Td6fnar/D00GtEYQ9TEO+tUBFz5BcPLDNlNYlWd9gYskLiebUQjbs c9nGz9QNvkCAbVeD0TaRoN78OaE7N/WbtoiyA= Received: by 10.223.103.148 with SMTP id k20mr387514fao.37.1283971473037; Wed, 08 Sep 2010 11:44:33 -0700 (PDT) Received: from [10.150.51.211] (gw0.net.jmsp.net [212.23.165.14]) by mx.google.com with ESMTPS id u8sm238547fah.36.2010.09.08.11.44.30 (version=SSLv3 cipher=RC4-MD5); Wed, 08 Sep 2010 11:44:32 -0700 (PDT) Subject: Re: [PATCH net-next-2.6] net: introduce rcu_dereference_rtnl From: Eric Dumazet To: Ben Hutchings Cc: Jarek Poplawski , David Miller , netdev In-Reply-To: <1283970567.2237.0.camel@achroite.uk.solarflarecom.com> References: <1283890291.2634.143.camel@edumazet-laptop> <4C86A558.6030802@gmail.com> <1283893657.2634.210.camel@edumazet-laptop> <1283970567.2237.0.camel@achroite.uk.solarflarecom.com> Date: Wed, 08 Sep 2010 20:44:29 +0200 Message-ID: <1283971469.2428.9.camel@edumazet-laptop> Mime-Version: 1.0 X-Mailer: Evolution 2.28.3 Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Le mercredi 08 septembre 2010 à 19:29 +0100, Ben Hutchings a écrit : > No semicolon on the end, please. The 'caller' will add that. Oh definitely, thanks ! [PATCH net-next-2.6] net: introduce rcu_dereference_rtnl We use rcu_dereference_check(p, rcu_read_lock_held() || lockdep_rtnl_is_held()) several times in network stack. More usages to come too, so its time to create a helper. Signed-off-by: Eric Dumazet --- include/linux/rtnetlink.h | 11 +++++++++++ 1 file changed, 11 insertions(+) -- 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/linux/rtnetlink.h b/include/linux/rtnetlink.h index 58d4449..263690d 100644 --- a/include/linux/rtnetlink.h +++ b/include/linux/rtnetlink.h @@ -749,6 +749,17 @@ extern int rtnl_is_locked(void); extern int lockdep_rtnl_is_held(void); #endif /* #ifdef CONFIG_PROVE_LOCKING */ +/** + * rcu_dereference_rtnl - rcu_dereference with debug checking + * @p: The pointer to read, prior to dereferencing + * + * Do an rcu_dereference(p), but check caller either holds rcu_read_lock() + * or RTNL + */ +#define rcu_dereference_rtnl(p) \ + rcu_dereference_check(p, rcu_read_lock_held() || \ + lockdep_rtnl_is_held()) + extern void rtnetlink_init(void); extern void __rtnl_unlock(void);