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=-9.1 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 30E72C04AB1 for ; Mon, 13 May 2019 09:15:05 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 025A920989 for ; Mon, 13 May 2019 09:15:05 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="nzC/5mp4" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728854AbfEMJPD (ORCPT ); Mon, 13 May 2019 05:15:03 -0400 Received: from mail-pg1-f194.google.com ([209.85.215.194]:41049 "EHLO mail-pg1-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728618AbfEMJN1 (ORCPT ); Mon, 13 May 2019 05:13:27 -0400 Received: by mail-pg1-f194.google.com with SMTP id z3so6451095pgp.8 for ; Mon, 13 May 2019 02:13:27 -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=TobEgud37AkGtwOzepZXi6SMrPv78tbjIgOahu678e4=; b=nzC/5mp4R12YfKsXBdkXjp/pMF2No3/DKiw6YJMyiBnuLgMxkPNtsIRMHcW1zlea5X 7UqPQCVccqlCIUGYGdOcOUFn6hVzNn6euXGC7QyYYt4gXTlsfC9eo8M6uZLbm2ZIcaRh /Ap7fGt3q5GxAoDuKFCLxgOrgIsE/eQVv0X7WZ55NlMfcymxtkIb1p+Uqj71PE1sSY6b 4jWL/6AEATSKzeIZerx7kfPsh5DRnIBlpm/n5tKStXJcuh+gfw7EbrQpFmn1yUyShTWt b0xRugDNpcblCWDES3OJvVxdW7r/Gbeu5jBcpj51NENjWhlHteTwnTfk5CgGn2GonIor y1vA== 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=TobEgud37AkGtwOzepZXi6SMrPv78tbjIgOahu678e4=; b=QVUdX60To6bpdlqFzzZzN1N4bRYmf//ZxgblxOfBg7X6ZB5xWQgubroXw87P10UlbL axfWmgF/OTMMDJax4q5LFE000LMvhVeqbVT1ivOVQhtpY+vJt1jXd6hKSA12b+kQGSUC /PC2HuGzAzE9FY1G46PuM5DsXcecfI6he+4vu05THEevvsY3tZrRFAWEFKqzM1Iuw5cf FQ1OlS5CpDt2WPFfATdBwPZd2suQBzs7/OwGsQKKobQHMO90etQthN5rU+HdPKrp5iAS pTbYTZPgFEVfQrHhvIUPoNmI7Bh6lM3TSJfob2BIN0HwU30ndIe3HKJpRnp1tjRqF1CD npug== X-Gm-Message-State: APjAAAUlNeKfLAhs69ybZUX+xL7rgkt3EInR46sgoV/TSlViT1mCB7vy 31OHBeatQA8tJIvRXLEoxXY= X-Google-Smtp-Source: APXvYqyTbq/Wr6EUR0i+iB22ZupBhh4NVmE65Q13SyIaRVMEgml42iqebzxneFl/9sUFKS0D6JyNDw== X-Received: by 2002:a63:8149:: with SMTP id t70mr30013740pgd.134.1557738807199; Mon, 13 May 2019 02:13:27 -0700 (PDT) Received: from localhost.localdomain ([203.100.54.194]) by smtp.gmail.com with ESMTPSA id n18sm35500837pfi.48.2019.05.13.02.13.24 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 13 May 2019 02:13:26 -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, boqun.feng@gmail.com, linux-kernel@vger.kernel.org, Yuyang Du Subject: [PATCH 03/17] locking/lockdep: Add helper functions to operate on the searched path Date: Mon, 13 May 2019 17:11:49 +0800 Message-Id: <20190513091203.7299-4-duyuyang@gmail.com> X-Mailer: git-send-email 2.20.1 (Apple Git-117) In-Reply-To: <20190513091203.7299-1-duyuyang@gmail.com> References: <20190513091203.7299-1-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 4091002..0617375 100644 --- a/kernel/locking/lockdep.c +++ b/kernel/locking/lockdep.c @@ -1365,6 +1365,37 @@ 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 (target->class == 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