From patchwork Thu May 4 18:29:24 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Brian Foster X-Patchwork-Id: 9712501 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 4245660235 for ; Thu, 4 May 2017 18:34:11 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 2190928625 for ; Thu, 4 May 2017 18:34:11 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 1635D286B7; Thu, 4 May 2017 18:34:11 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 8368D2861C for ; Thu, 4 May 2017 18:34:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755958AbdEDSai (ORCPT ); Thu, 4 May 2017 14:30:38 -0400 Received: from mx1.redhat.com ([209.132.183.28]:32804 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754701AbdEDS30 (ORCPT ); Thu, 4 May 2017 14:29:26 -0400 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.phx2.redhat.com [10.5.11.16]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 0E462804EF for ; Thu, 4 May 2017 18:29:26 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mx1.redhat.com 0E462804EF Authentication-Results: ext-mx03.extmail.prod.ext.phx2.redhat.com; dmarc=none (p=none dis=none) header.from=redhat.com Authentication-Results: ext-mx03.extmail.prod.ext.phx2.redhat.com; spf=pass smtp.mailfrom=bfoster@redhat.com DKIM-Filter: OpenDKIM Filter v2.11.0 mx1.redhat.com 0E462804EF Received: from bfoster.bfoster (dhcp-41-20.bos.redhat.com [10.18.41.20]) by smtp.corp.redhat.com (Postfix) with ESMTP id E51285C54F for ; Thu, 4 May 2017 18:29:25 +0000 (UTC) Received: by bfoster.bfoster (Postfix, from userid 1000) id BFAF512150D; Thu, 4 May 2017 14:29:24 -0400 (EDT) From: Brian Foster To: linux-xfs@vger.kernel.org Subject: [PATCH] xfs: make fatal assert failures conditional in debug mode Date: Thu, 4 May 2017 14:29:24 -0400 Message-Id: <1493922564-14273-1-git-send-email-bfoster@redhat.com> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.16 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.27]); Thu, 04 May 2017 18:29:26 +0000 (UTC) Sender: linux-xfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-xfs@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP XFS currently supports two debug modes: XFS_WARN enables assert failure warnings and XFS_DEBUG converts assert failures to fatal errors (via BUG()) and enables additional runtime debug code. While the behavior to BUG the kernel on assert failure is useful in certain test scenarios, it is also useful for development/debug to enable debug mode code without having to crash the kernel on an assert failure. To provide this additional flexibility, update XFS debug mode to not BUG() the kernel by default and create a new XFS kernel configuration option to enable fatal assert failures when debug mode is enabled. To provide backwards compatibility with current behavior, enable the fatal asserts option by default when debug mode is enabled. Signed-off-by: Brian Foster --- Hi all, This tweaks the rfc version based on feedback from Christoph and Darrick. The config option is renamed to minimize confusion and the logic is basically flipped to disable BUG() behavior by default in XFS_DEBUG mode and have the new config option turn it on. This option is dependent on DEBUG mode because I don't believe there is a compelling use case for XFS_WARN mode with fatal asserts and I'd rather not unnecessarily increase the configuration matrix. Note that the new config option is set 'default y' simply to provide backwards compatibility with current behavior (so users expecting DEBUG mode kernels to BUG() will continue to see that behavior without requiring further config modifications). Thoughts, reviews, flames appreciated. Brian v1: - Use a new config option rather than reuse XFS_WARN. - Disable BUG() in DEBUG mode by default and flip the logic of the new config option. rfc: http://www.spinics.net/lists/linux-xfs/msg06390.html fs/xfs/Kconfig | 8 ++++++++ fs/xfs/xfs.h | 4 ++++ fs/xfs/xfs_linux.h | 32 +++++++++++++++++++------------- 3 files changed, 31 insertions(+), 13 deletions(-) diff --git a/fs/xfs/Kconfig b/fs/xfs/Kconfig index 35faf12..ded25f8 100644 --- a/fs/xfs/Kconfig +++ b/fs/xfs/Kconfig @@ -96,3 +96,11 @@ config XFS_DEBUG not useful unless you are debugging a particular problem. Say N unless you are an XFS developer, or you play one on TV. + +config XFS_ASSERT_FATAL + bool "XFS fatal asserts" + default y + depends on XFS_FS && XFS_DEBUG + help + Say Y here to convert DEBUG mode ASSERT failures into fatal errors + that BUG() the kernel. Otherwise, ASSERT failures result in warnings. diff --git a/fs/xfs/xfs.h b/fs/xfs/xfs.h index a742c47..80cd0fd 100644 --- a/fs/xfs/xfs.h +++ b/fs/xfs/xfs.h @@ -24,6 +24,10 @@ #define XFS_BUF_LOCK_TRACKING 1 #endif +#ifdef CONFIG_XFS_ASSERT_FATAL +#define XFS_ASSERT_FATAL 1 +#endif + #ifdef CONFIG_XFS_WARN #define XFS_WARN 1 #endif diff --git a/fs/xfs/xfs_linux.h b/fs/xfs/xfs_linux.h index 044fb0e..36c3eab 100644 --- a/fs/xfs/xfs_linux.h +++ b/fs/xfs/xfs_linux.h @@ -245,37 +245,43 @@ static inline __uint64_t howmany_64(__uint64_t x, __uint32_t y) return x; } +/* + * ASSERT() definitions + */ #define ASSERT_ALWAYS(expr) \ (likely(expr) ? (void)0 : assfail(#expr, __FILE__, __LINE__)) -#ifdef DEBUG +#if defined(DEBUG) && defined(XFS_ASSERT_FATAL) + #define ASSERT(expr) \ (likely(expr) ? (void)0 : assfail(#expr, __FILE__, __LINE__)) -#ifndef STATIC -# define STATIC noinline -#endif - -#else /* !DEBUG */ - -#ifdef XFS_WARN +#elif defined(DEBUG) || defined(XFS_WARN) #define ASSERT(expr) \ (likely(expr) ? (void)0 : asswarn(#expr, __FILE__, __LINE__)) -#ifndef STATIC -# define STATIC static noinline +#else + +#define ASSERT(expr) ((void)0) + #endif -#else /* !DEBUG && !XFS_WARN */ +/* + * STATIC definitions + */ +#ifdef DEBUG + +#ifndef STATIC +# define STATIC noinline +#endif -#define ASSERT(expr) ((void)0) +#else /* !DEBUG */ #ifndef STATIC # define STATIC static noinline #endif -#endif /* XFS_WARN */ #endif /* DEBUG */ #ifdef CONFIG_XFS_RT