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=-8.8 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_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 4671BC43381 for ; Mon, 18 Mar 2019 08:58:22 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 1457A20857 for ; Mon, 18 Mar 2019 08:58:22 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="jF5G5RXm" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727455AbfCRI6U (ORCPT ); Mon, 18 Mar 2019 04:58:20 -0400 Received: from mail-pg1-f194.google.com ([209.85.215.194]:32932 "EHLO mail-pg1-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727429AbfCRI6R (ORCPT ); Mon, 18 Mar 2019 04:58:17 -0400 Received: by mail-pg1-f194.google.com with SMTP id i7so7708313pgq.0 for ; Mon, 18 Mar 2019 01:58:17 -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:in-reply-to:references; bh=HZtu1dgITnZTUGFaUngQpYQEU/UJAEfhiDxYPu729A8=; b=jF5G5RXmbh2pKZRfGIv5zBhsCCaSTcopeQiY+lLygdWh5Y50Fg1PN8FHnQAX/u8X2U uOIRWRdzaenR3wBAy3loc5PCrjSz/Gu2fdYWugeDrDCyTow3aS+wd47QN0JOBUXAZgMs jZv/Yohi/bcS5Z9gx+DK6FeRisa3stlK+r5NPNQZnMwXwl0KHwoozQwRDevV8KsYjM4i lzSKhFD1oMF/LcQXCjjSZOPVuyeT9BMk/AN+d/Zl/vGQ7pY0tpF1BtATf62EZ/Ygdvhe 8ZvbQVRH4FJatuEkClZhKKQr9yrMK3nvEXyoY5C8hIdO8TmBQmLfp1uEi/HGQxh1muWd kPjA== 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:in-reply-to :references; bh=HZtu1dgITnZTUGFaUngQpYQEU/UJAEfhiDxYPu729A8=; b=hjDogFSKN82h0bM3/nixBdTiCLoTBIcOHi1ec/RiRrLWcl0EwC2T71+RBA4xUlzHb5 rf96T7GmrW5ttOlal+pJaIeljOCWo/iQ3t7EeZVb18nNYJjpHDbHdhLMLIV4Wg/D0syN CiUGm6hoAlCrsmd0UPFB6VxS8/Iz23sVMYYyu5fTipJD1PnsynqG6+jod9jbKVy6gqKY e8RoQFEfeTh2OwV4D9T+FNe6Et/jNGMk8LR1tb4e+yIZ/GFzN+635ZCkadGR3jSorgbH JdIMHbCYahOpmP3ap7VO4n6QzG3i+Hv1UoBG6dk1jdPNc7ITifOOGC2n55mI7xaTMBTP oXrg== X-Gm-Message-State: APjAAAWNo94D9RATGLQW5OxtCJZb3CLYUKDsYvNu0w7AeiBZSLjWp6i3 8lWeQixM0V0Z3UD13bxOR8WXVIUAF8jhWw== X-Google-Smtp-Source: APXvYqzO7PAN/cWTyhNk+RIm6kKE+OKVxNOwgi+dmG9VIuLMY3/C5T6EqHKM+Tf19nwuJjwSaSrkZw== X-Received: by 2002:a17:902:b097:: with SMTP id p23mr18612945plr.36.1552899497274; Mon, 18 Mar 2019 01:58:17 -0700 (PDT) Received: from localhost.localdomain ([203.100.54.194]) by smtp.gmail.com with ESMTPSA id k8sm11147024pgq.37.2019.03.18.01.58.14 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 18 Mar 2019 01:58:16 -0700 (PDT) From: Yuyang Du To: peterz@infradead.org, will.deacon@arm.com, mingo@kernel.org Cc: bvanassche@acm.org, ming.lei@redhat.com, linux-kernel@vger.kernel.org, Yuyang Du Subject: [PATCH v2 12/19] locking/lockdep: Update comment Date: Mon, 18 Mar 2019 16:57:26 +0800 Message-Id: <20190318085733.3143-13-duyuyang@gmail.com> X-Mailer: git-send-email 2.17.2 (Apple Git-113) In-Reply-To: <20190318085733.3143-1-duyuyang@gmail.com> References: <20190318085733.3143-1-duyuyang@gmail.com> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org An out-of-nowhere comment is removed. While at it, add more explanatory comments. Such a trivial patch! Signed-off-by: Yuyang Du --- kernel/locking/lockdep.c | 12 +++++++++--- 1 file changed, 9 insertions(+), 3 deletions(-) diff --git a/kernel/locking/lockdep.c b/kernel/locking/lockdep.c index dcff644..250ba64 100644 --- a/kernel/locking/lockdep.c +++ b/kernel/locking/lockdep.c @@ -2717,10 +2717,16 @@ static int validate_chain(struct task_struct *curr, * - is softirq-safe, if this lock is hardirq-unsafe * * And check whether the new lock's dependency graph - * could lead back to the previous lock. + * could lead back to the previous lock: * - * any of these scenarios could lead to a deadlock. If - * All validations + * - within the current held-lock stack + * - across our accumulated lock dependency records + * + * any of these scenarios could lead to a deadlock. + */ + /* + * The simple case: does the current hold the same lock + * already? */ int ret = check_deadlock(curr, hlock, hlock->read); -- 1.8.3.1