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=-9.0 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 BA4E3C3A59F for ; Thu, 29 Aug 2019 08:33:05 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 8B9CB2053B for ; Thu, 29 Aug 2019 08:33:05 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="sefnPZfK" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727941AbfH2IdE (ORCPT ); Thu, 29 Aug 2019 04:33:04 -0400 Received: from mail-pl1-f194.google.com ([209.85.214.194]:36727 "EHLO mail-pl1-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727889AbfH2IdA (ORCPT ); Thu, 29 Aug 2019 04:33:00 -0400 Received: by mail-pl1-f194.google.com with SMTP id f19so1250479plr.3 for ; Thu, 29 Aug 2019 01:32:59 -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=lNw8f3YA0DZukVEGbXPjsA/vyBkyObawvtOHlKkIee4=; b=sefnPZfKls3P9ky+DVoLfW6A9lqoVwcGMHP4hhzS9Zg3gRmN7U+dqe/r2YrY+Uo/oy GklTNg9vOjfWuglFaWiB6sBO5uncDBKJCZvUn9rjS/CeyaoFCmljJuL00NiYu2SpNRAb KE8ay6CZ3qh0skNs+IYNLSYIkIfhvv7M1j1bKA3fXb+AEArniVQ3oI2hF6sHXF+h/w8j etWCoAKJQo7c43elviTkvpfpjSYnFgiYCQXLxqX1hD5AeTxaLncgPh4JMKxzxO5FFl0h uCHnjNNBRjxtvpozgEF3/VnwMWLgNs0SR5rx3UXtQd5x0ffwUwiyaBEq/CIi2GclDo69 ikHw== 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=lNw8f3YA0DZukVEGbXPjsA/vyBkyObawvtOHlKkIee4=; b=Xd+N9pfrIRZeveyVCtM1WTdUwjlNIlLAKK6D/k2LukIG2Uf8MG9kbiYr3pcC9L/Yvq qUqD45+/dJaZJsJUmrvlUKkGz8eFcjBQThfGCIP9/JFAxEjUb1u1jHLBm5yJljdREpjC gvKDdHjRNiJZRgHD+uat99LmP2xtUhQzv0RFzodViX64t/CzVb2VaE7ZkLYVO3kFE8Uj WePlR8KPNcWS82bbtyeQTFB+q0rbP7zIugyChkyWJZ5TxaEYWK+r0hbpH/9XLhdLGblN 45Ni8wZ2bXRjxC4zRtHZ7U3PsRABHiZMgNeAz5gt1lTwBGUhDFW4MZuGXWr/bKm7/Uhl anmg== X-Gm-Message-State: APjAAAUki6WxmLDxwgmh/vwnAj7MVqSMv2/AyaXVKHUXGm05PVaQhECP OuyTaI1i7H58FLgBL/zZyqM= X-Google-Smtp-Source: APXvYqxUIg3uZ/+/r1Bgjx0rPKDe0xLX2t3FWr19uDIX5PHEIem1Nds9yT8RFhZQZ/m/8Q1s3Zxr6A== X-Received: by 2002:a17:902:a404:: with SMTP id p4mr8320726plq.185.1567067579478; Thu, 29 Aug 2019 01:32:59 -0700 (PDT) Received: from localhost.localdomain ([203.100.54.194]) by smtp.gmail.com with ESMTPSA id v22sm1260155pgk.69.2019.08.29.01.32.55 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 29 Aug 2019 01:32:58 -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 v4 19/30] locking/lockdep: Add helper functions to operate on the searched path Date: Thu, 29 Aug 2019 16:31:21 +0800 Message-Id: <20190829083132.22394-20-duyuyang@gmail.com> X-Mailer: git-send-email 2.20.1 (Apple Git-117) In-Reply-To: <20190829083132.22394-1-duyuyang@gmail.com> References: <20190829083132.22394-1-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 18303ff..41cb735 100644 --- a/kernel/locking/lockdep.c +++ b/kernel/locking/lockdep.c @@ -1535,6 +1535,37 @@ 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