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,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 336A0C4321A for ; Fri, 28 Jun 2019 09:17:09 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 0833A215EA for ; Fri, 28 Jun 2019 09:17:09 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="TgKhK0sx" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727043AbfF1JRH (ORCPT ); Fri, 28 Jun 2019 05:17:07 -0400 Received: from mail-pf1-f195.google.com ([209.85.210.195]:35861 "EHLO mail-pf1-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726601AbfF1JRE (ORCPT ); Fri, 28 Jun 2019 05:17:04 -0400 Received: by mail-pf1-f195.google.com with SMTP id r7so2672733pfl.3 for ; Fri, 28 Jun 2019 02:17:04 -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 :mime-version:content-transfer-encoding; bh=6hNfLq2QCvJHZK9LmMDQloHxl/I8j8TcQn+ws0k98tc=; b=TgKhK0sx1k7Pcoah+JCOd06OKSvwWJhHk3l6le8+L8ozLhqbujQ7eYWVafDdiGvhf1 +23ruH2QlZYvhCRgbb3BcOVprL+Y2TPh9Ow3yBYaGuVsQ3E0mVBA/c5Jd8YAybSTHkHE DUv3LEYoifiNcdSB+CkX3VO9Z5ALqpykIOjVYCU+3tvV6sILYyp4Q5Em4AQTGxDji5Cd b6gcK5uoD13fopTVhThDrwjnSZH9ibmnlhPTBcfsZuG/PAp/f4EjPxf/FfBn8g6aqDIr 9AKL0dZHllkRHubgjgwsm2hV9ord9jlBWpwUFPkgHRUOValGuHAdx41jXSYHQe66HkAw qSCg== 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:mime-version:content-transfer-encoding; bh=6hNfLq2QCvJHZK9LmMDQloHxl/I8j8TcQn+ws0k98tc=; b=tz7j+k5rJb8aM2CGtlGobKwG57MkEF27TvRJ/VQkTFpteBUjLbybFE0mEP9AeSpyXA 7FKoVYjBjSl4rqWGcKxmlfrb5l34wQpy++SrwBFmj4TS1al32ukEYHse26aUx1DaSjwB AkxDbUbavTrttw0Eyn8Ay+Jp/MoUZPLlwLt6Wjouki6jRRjPKTNt79PGzjz4F0aDO4+i XAoxttHbZ8xxxsYx4Y5IRll0VsF5jLgRLeTVuDaLkyVEB+d2YjazJ3LOnw5rKXxprszn lo9M2fca5YiJKUoEP7x22EEB9BLQGn3Bzg4eJiEzWia8eXYjpM+Ml6NpcZxacC0C6qq2 8k2Q== X-Gm-Message-State: APjAAAUEtr5lsAvL+V4v1/nlfvePYa/QnyYGK07WzdelxZPqkwMyqkgR cjNZiN4w+0rX5yDIOQ7yVIg= X-Google-Smtp-Source: APXvYqzPzSvtIzPqktKoz50uxgLFrBNVvI332ZIR4OgTutemRdyKvqjGf0FkD9cwkQSvSAxGmWW95g== X-Received: by 2002:a63:6d8d:: with SMTP id i135mr1293724pgc.303.1561713424155; Fri, 28 Jun 2019 02:17:04 -0700 (PDT) Received: from localhost.localdomain ([203.100.54.194]) by smtp.gmail.com with ESMTPSA id x65sm1754521pfd.139.2019.06.28.02.17.00 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Fri, 28 Jun 2019 02:17:03 -0700 (PDT) From: Yuyang Du To: peterz@infradead.org, will.deacon@arm.com, mingo@kernel.org Cc: bvanassche@acm.org, ming.lei@redhat.com, frederic@kernel.org, tglx@linutronix.de, linux-kernel@vger.kernel.org, longman@redhat.com, paulmck@linux.vnet.ibm.com, boqun.feng@gmail.com, Yuyang Du Subject: [PATCH v3 18/30] locking/lockdep: Add helper functions to operate on the searched path Date: Fri, 28 Jun 2019 17:15:16 +0800 Message-Id: <20190628091528.17059-19-duyuyang@gmail.com> X-Mailer: git-send-email 2.20.1 (Apple Git-117) In-Reply-To: <20190628091528.17059-1-duyuyang@gmail.com> References: <20190628091528.17059-1-duyuyang@gmail.com> 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 - find_lock_in_path() tries to find whether a lock class is in the path. - find_next_dep_in_path() returns the next dependency after a given dependency in the path. Signed-off-by: Yuyang Du --- kernel/locking/lockdep.c | 31 +++++++++++++++++++++++++++++++ 1 file changed, 31 insertions(+) diff --git a/kernel/locking/lockdep.c b/kernel/locking/lockdep.c index 1805017..9fa38fb 100644 --- a/kernel/locking/lockdep.c +++ b/kernel/locking/lockdep.c @@ -1463,6 +1463,37 @@ static inline int get_lock_depth(struct lock_list *child) } /* + * Return the dependency if @lock is in the path, otherwise NULL. + */ +static inline struct lock_list * +find_lock_in_path(struct lock_class *lock, struct lock_list *target) +{ + while ((target = get_lock_parent(target))) + if (fw_dep_class(target) == lock) + return target; + + return NULL; +} + +/* + * Walk back to the next dependency after @source from @target. Note + * that @source must be in the path, and @source can not be the same as + * @target, otherwise this is going to fail and reutrn NULL. + */ +static inline struct lock_list * +find_next_dep_in_path(struct lock_list *source, struct lock_list *target) +{ + while (get_lock_parent(target) != source) { + target = get_lock_parent(target); + + if (!target) + break; + } + + return target; +} + +/* * Return the forward or backward dependency list. * * @lock: the lock_list to get its class's dependency list -- 1.8.3.1