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=-15.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,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 DC43DC2B9F4 for ; Thu, 17 Jun 2021 14:29:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B824E613CB for ; Thu, 17 Jun 2021 14:29:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232730AbhFQObd (ORCPT ); Thu, 17 Jun 2021 10:31:33 -0400 Received: from pv50p00im-zteg10011501.me.com ([17.58.6.42]:53856 "EHLO pv50p00im-zteg10011501.me.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232588AbhFQOb1 (ORCPT ); Thu, 17 Jun 2021 10:31:27 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=me.com; s=1a1hai; t=1623940159; bh=48jYlHHtDDHkWHfxggM04atL+5HJ384LjyBoX+V1N5Q=; h=From:To:Subject:Date:Message-Id:MIME-Version; b=AJmZG2ZZXS8/uQlbAJRQe5jEyct5Z4juXnWrX0RAO3H2OOfC3nE4w9ATtrRfIyNs9 CsLt/rBGs8BDqoEycHpzVSjAunJvLiKlQX3yPDM7OLec6ATocy75UXOUIhFDfEV5Z2 VJmRgbfY+4+DGthaAWj6r9J5DwUm47mfRPkQ+8H+9Ix46UEGP7wHX09xDThf7/Kh5H qFd1FF1U6mWWkALff8r1QVFzr6NYg50mA4fUZkVOoaKlLaTt33HRuKl+Eo9Id0XevJ LdNQA5cMx9LmynFgQ8xKxC6zY5iIieOJUi3plM8tZBref7G9noyDfIiD1Qy/kXTXRe /U3A2sqS8/PdA== Received: from xiongwei.. (unknown [120.245.2.120]) by pv50p00im-zteg10011501.me.com (Postfix) with ESMTPSA id 7D4F6B00487; Thu, 17 Jun 2021 14:29:16 +0000 (UTC) From: Xiongwei Song To: peterz@infradead.org, mingo@redhat.com, will@kernel.org, longman@redhat.com, boqun.feng@gmail.com Cc: linux-kernel@vger.kernel.org, Xiongwei Song Subject: [PATCH 3/3] locking/lockdep: print possible warning after counting deps Date: Thu, 17 Jun 2021 22:28:28 +0800 Message-Id: <20210617142828.346111-4-sxwjean@me.com> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20210617142828.346111-1-sxwjean@me.com> References: <20210617142828.346111-1-sxwjean@me.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.391,18.0.790 definitions=2021-06-17_13:2021-06-15,2021-06-17 signatures=0 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 suspectscore=0 malwarescore=0 phishscore=0 bulkscore=0 spamscore=0 clxscore=1015 mlxscore=0 mlxlogscore=822 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-2009150000 definitions=main-2106170092 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Xiongwei Song The graph walk might hit error when counting dependencies. Once the return value is negative, print a warning to reminder users. Suggested-by: Waiman Long Signed-off-by: Xiongwei Song --- kernel/locking/lockdep.c | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-) diff --git a/kernel/locking/lockdep.c b/kernel/locking/lockdep.c index cb94097014d8..cfe0f4374594 100644 --- a/kernel/locking/lockdep.c +++ b/kernel/locking/lockdep.c @@ -2028,8 +2028,12 @@ static unsigned long __lockdep_count_forward_deps(struct lock_list *this) { unsigned long count = 0; struct lock_list *target_entry; + enum bfs_result ret; + + ret = __bfs_forwards(this, (void *)&count, noop_count, NULL, &target_entry); - __bfs_forwards(this, (void *)&count, noop_count, NULL, &target_entry); + if (bfs_error(ret)) + print_bfs_bug(ret); return count; } @@ -2053,8 +2057,12 @@ static unsigned long __lockdep_count_backward_deps(struct lock_list *this) { unsigned long count = 0; struct lock_list *target_entry; + enum bfs_result ret; + + ret = __bfs_backwards(this, (void *)&count, noop_count, NULL, &target_entry); - __bfs_backwards(this, (void *)&count, noop_count, NULL, &target_entry); + if (bfs_error(ret)) + print_bfs_bug(ret); return count; } -- 2.30.2