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=-8.6 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,HK_RANDOM_FROM,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, 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 A1736C606B0 for ; Tue, 9 Jul 2019 10:15:35 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 65C7220645 for ; Tue, 9 Jul 2019 10:15:35 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="FIZCFwI3" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726341AbfGIKPe (ORCPT ); Tue, 9 Jul 2019 06:15:34 -0400 Received: from mail-pf1-f196.google.com ([209.85.210.196]:34965 "EHLO mail-pf1-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726045AbfGIKPd (ORCPT ); Tue, 9 Jul 2019 06:15:33 -0400 Received: by mail-pf1-f196.google.com with SMTP id u14so7876209pfn.2 for ; Tue, 09 Jul 2019 03:15:33 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=WA5gtuo+ySOXWIRiIrkIDOQyLhIa86b74KS4PTR9iAM=; b=FIZCFwI3aBiR/vggDtx3YbxukWikWD/bDAZ+PULJfXWC5pJAtF9fan84oIQvdBAv1z FrznwbgKfcmVahncHfLTinXidR1k5BhS41Nb+Ge5XSryESE3NKSAQgNZ+5bKQO1VSvqY +eZh7xy9s7HiJwSWt3MnC2Yui/V5TBHCURh1zeevkFSz3sYeGbR3apVok8/B/1W6PujA y1SsdtPcOmH6HVcJQ0meqk0ue2UCT151epRyaq6Cs/3eHyduHznh9hFzceYNnvAAwddD doDztV60kGrUHN+LdImWdIn7o2AgTiHVitNJOWw6RTybGCMbYvPmBHItBpD/Gyr3mKM0 B5uA== 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:mime-version :content-transfer-encoding; bh=WA5gtuo+ySOXWIRiIrkIDOQyLhIa86b74KS4PTR9iAM=; b=GybackT+ltQnJU1zIQhmFvLVCXe47LlaSAfclbXaufgLPQdq3a7Lu6LlX6C/FW85cG EnfN0ZvJqZMwqDmieFP+0EqVue0HQpw017N7LBLbiCCFoWahxPMpKcv26+tWcCA1xz+X //gGcfxeOynhEuR2lLR7XDAc4FPNw8EAETdsBRv5qYMbGLmO9JIITb9YULJFtlT57MwA MXnjpPSAgbPGpnQpAr5iU8o+5Tur3Ei1lqomUyOR70UrWl/Irf7ne6NmbOpnr0kc7xHo vUS65k7aM4wv7UjqaTl5fs2rXJJUcA3vH+ix0lm6BLrZOyXn+u/WeHM0ItFJOrstwy73 hE8w== X-Gm-Message-State: APjAAAW718gvjQ4QXYkv2WBerwzL+81G14hEs/I4Jr5LJPAYBMHRb9g/ ami3/ou40J0/COAThafYFFA= X-Google-Smtp-Source: APXvYqyYbZ2FcPOM4BrBIsJaKGs2wX4QGplboi4GLRlBACy/APhEYK73afvGEAyA6IiDHBBQMpEwxQ== X-Received: by 2002:a63:6901:: with SMTP id e1mr1697000pgc.390.1562667333181; Tue, 09 Jul 2019 03:15:33 -0700 (PDT) Received: from localhost.localdomain ([203.100.54.194]) by smtp.gmail.com with ESMTPSA id i15sm22195320pfd.160.2019.07.09.03.15.30 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 09 Jul 2019 03:15:32 -0700 (PDT) From: Yuyang Du To: peterz@infradead.org, will.deacon@arm.com, mingo@kernel.org Cc: linux-kernel@vger.kernel.org, frederic@kernel.org, arnd@arndb.de, cai@lca.pw, Yuyang Du Subject: [PATCH] locking/lockdep: Fix lock used or unused stats error Date: Tue, 9 Jul 2019 18:15:22 +0800 Message-Id: <20190709101522.9117-1-duyuyang@gmail.com> X-Mailer: git-send-email 2.20.1 (Apple Git-117) MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org The stats variable nr_unused_locks is incremented every time a new lock class is register and decremented when the lock is first used in __lock_acquire(). And after all, it is shown and checked in lockdep_stats. However, under configurations that either CONFIG_TRACE_IRQFLAGS or CONFIG_PROVE_LOCKING is not defined: The commit: 091806515124b20 ("locking/lockdep: Consolidate lock usage bit initialization") missed marking the LOCK_USED flag at IRQ usage initialization because as mark_usage() is not called. And the commit: 886532aee3cd42d ("locking/lockdep: Move mark_lock() inside CONFIG_TRACE_IRQFLAGS && CONFIG_PROVE_LOCKING") further made mark_lock() not defined such that the LOCK_USED cannot be marked at all when the lock is first acquired. As a result, we fix this by not showing and checking the stats under such configurations for lockdep_stats. Reported-by: Qian Cai Signed-off-by: Yuyang Du --- kernel/locking/lockdep_proc.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/kernel/locking/lockdep_proc.c b/kernel/locking/lockdep_proc.c index 9c49ec6..65b6a16 100644 --- a/kernel/locking/lockdep_proc.c +++ b/kernel/locking/lockdep_proc.c @@ -210,6 +210,7 @@ static int lockdep_stats_show(struct seq_file *m, void *v) nr_hardirq_read_safe = 0, nr_hardirq_read_unsafe = 0, sum_forward_deps = 0; +#ifdef CONFIG_PROVE_LOCKING list_for_each_entry(class, &all_lock_classes, lock_entry) { if (class->usage_mask == 0) @@ -241,13 +242,13 @@ static int lockdep_stats_show(struct seq_file *m, void *v) if (class->usage_mask & LOCKF_ENABLED_HARDIRQ_READ) nr_hardirq_read_unsafe++; -#ifdef CONFIG_PROVE_LOCKING sum_forward_deps += lockdep_count_forward_deps(class); -#endif } #ifdef CONFIG_DEBUG_LOCKDEP DEBUG_LOCKS_WARN_ON(debug_atomic_read(nr_unused_locks) != nr_unused); #endif + +#endif seq_printf(m, " lock-classes: %11lu [max: %lu]\n", nr_lock_classes, MAX_LOCKDEP_KEYS); seq_printf(m, " direct dependencies: %11lu [max: %lu]\n", -- 1.8.3.1