From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.8 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 71908C3F2D0 for ; Fri, 28 Feb 2020 09:25:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 468AE246A8 for ; Fri, 28 Feb 2020 09:25:35 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="YDnPp8u7" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726740AbgB1JZe (ORCPT ); Fri, 28 Feb 2020 04:25:34 -0500 Received: from mail-pf1-f195.google.com ([209.85.210.195]:38557 "EHLO mail-pf1-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726148AbgB1JZd (ORCPT ); Fri, 28 Feb 2020 04:25:33 -0500 Received: by mail-pf1-f195.google.com with SMTP id x185so1427029pfc.5 for ; Fri, 28 Feb 2020 01:25:33 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id; bh=S4gi9DzSp14YfzPR+D6JqNOQzoOlU/CqGMZ0Lo8rA+c=; b=YDnPp8u7WnB9/6IZXgEYCyJSViWmwiFsC345TIUcvvG3v/GUmiz7WpyysoNxEeuY2n 0YqUP42Fhp54Quqfw6YTz+MHvfenBa98IZ54dyQX++NA00VVfz8nhvbMPSSNCqPGkB8d OTZbYbSr9sNmkFzxxH44XoNelFGezLglte3e0L2aV0ROaEmFgEVCX2xI01234NcLd5W/ 81ZLGHaekmYv5WMzhjZIj9klUra0Nw64p/UM6HXaPbrgC6AdrU9VQChR0uy/nG8DR5CL 3r9TcXl+mLgF31Yz6z2tx1IR5pOqu1yLDrQP/bnT5IcIVcf4+vGUwZwl04BxiN66k//7 6Knw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id; bh=S4gi9DzSp14YfzPR+D6JqNOQzoOlU/CqGMZ0Lo8rA+c=; b=Nfp+/n5kCFzxf/g5vLgH+n9TximZpuBHuXdt/tacRCRwGKVBECicyqsElzvHYI7Jj7 VOOmn9gd8qCXmGNWpxQyfY3AGM2mmgKqWrnBKh/gLZW+dVXHSp5coKWohKQ0ZB/Rni3f pnzTsgzf8KRiAangiDNm1nD+gLtgJCApi843aMizx6RYLcPzL+Am/SNDiS2elMqoFGEq ZwRqGeqlGIHkjUxXXGeorjBYR/8x6mI52TtCNSEphWWbwi9tRLVgyhIiloH3b5wlQNQ7 3iyrxGSBdnti8faYnVotV2N/QVzUgwG18I0pzQGaC5Wn7t7qeDmLgJtsptFlBTN3ct4j V4NA== X-Gm-Message-State: APjAAAXbfwJwM67HgNdSVMTjNEVeT/dpd7rU6NVOqMRlei9G2hJjuujv v33WYHjl9DZ2zSx1tFO8KQ== X-Google-Smtp-Source: APXvYqxO8OjxiM4PSWSKvXhkRqfpp3qwCEx8XbNcyqpZsEeoRg2ZZXQB3OB+d/3Pl3ILo7F60MlQGQ== X-Received: by 2002:a63:f403:: with SMTP id g3mr3764936pgi.62.1582881932838; Fri, 28 Feb 2020 01:25:32 -0800 (PST) Received: from localhost.localdomain ([2402:3a80:1ee0:f1c2:74cd:ab46:bb74:a4a3]) by smtp.gmail.com with ESMTPSA id r72sm1660500pjb.18.2020.02.28.01.25.27 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 28 Feb 2020 01:25:31 -0800 (PST) From: madhuparnabhowmik10@gmail.com To: paulmck@kernel.org, josh@joshtriplett.org, rostedt@goodmis.org, mathieu.desnoyers@efficios.com, jiangshanlai@gmail.com, joel@joelfernandes.org Cc: linux-kernel@vger.kernel.org, Madhuparna Bhowmik , Amol Grover Subject: [PATCH] Default enable RCU list lockdep debugging with PROVE_RCU Date: Fri, 28 Feb 2020 14:54:51 +0530 Message-Id: <20200228092451.10455-1-madhuparnabhowmik10@gmail.com> X-Mailer: git-send-email 2.17.1 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Madhuparna Bhowmik This patch default enables CONFIG_PROVE_RCU_LIST option with CONFIG_PROVE_RCU for RCU list lockdep debugging. With this change, RCU list lockdep debugging will be default enabled in CONFIG_PROVE_RCU=y kernels. Most of the RCU users (in core kernel/, drivers/, and net/ subsystem) have already been modified to include lockdep expressions hence RCU list debugging can be enabled by default. However, there are still chances of enountering false-positive lockdep splats because not everything is converted, in case RCU list primitives are used in non-RCU read-side critical section but under the protection of a lock. It would be okay to have a few false-positives, as long as bugs are identified, since this patch only affects debugging kernels. Co-developed-by: Amol Grover Signed-off-by: Amol Grover Signed-off-by: Madhuparna Bhowmik --- kernel/rcu/Kconfig.debug | 11 +++-------- 1 file changed, 3 insertions(+), 8 deletions(-) diff --git a/kernel/rcu/Kconfig.debug b/kernel/rcu/Kconfig.debug index 4aa02eee8f6c..ec4bb6c09048 100644 --- a/kernel/rcu/Kconfig.debug +++ b/kernel/rcu/Kconfig.debug @@ -9,15 +9,10 @@ config PROVE_RCU def_bool PROVE_LOCKING config PROVE_RCU_LIST - bool "RCU list lockdep debugging" - depends on PROVE_RCU && RCU_EXPERT - default n + def_bool PROVE_RCU help - Enable RCU lockdep checking for list usages. By default it is - turned off since there are several list RCU users that still - need to be converted to pass a lockdep expression. To prevent - false-positive splats, we keep it default disabled but once all - users are converted, we can remove this config option. + Enable RCU lockdep checking for list usages. It is default + enabled with CONFIG_PROVE_RCU. config TORTURE_TEST tristate -- 2.17.1