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 7872CC4321A for ; Fri, 28 Jun 2019 09:16:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4C7D02133F for ; Fri, 28 Jun 2019 09:16:26 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="OUxmbpjO" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726903AbfF1JQZ (ORCPT ); Fri, 28 Jun 2019 05:16:25 -0400 Received: from mail-pf1-f193.google.com ([209.85.210.193]:39179 "EHLO mail-pf1-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726562AbfF1JQY (ORCPT ); Fri, 28 Jun 2019 05:16:24 -0400 Received: by mail-pf1-f193.google.com with SMTP id j2so2661768pfe.6 for ; Fri, 28 Jun 2019 02:16:24 -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=Ok7LAiocwziPNLnJTigNrjpE5FyHnTrBjoEWno2vU9A=; b=OUxmbpjO++VwthWJNz4MH56TcHQeHrAp1zMRZKOBCB10CSq6eKs+R4AgUJhNO5UReY hoWJ1QRrKBZQh/cFrzV7QPvo8Ej91ISFcijnvDKttL8mkz67+8b1VGGW9v4X8mGNfGl5 Ia0oMj3kkd1PJ2zzAri5m/HHELD0K0szFUbiSqLvsWNJ+dcImYzINfEWFA9zrVg2GX5N cVIiny3+dIIJctqwdPYcjVKNE10lW6/0d5EwlbdQSgkkANrN33Q6qQ13/rae/OVa2+Q1 VlT21DqppUFwOoWY8zjcTjW1AWI/1JTdCRm55d47I5a7XFKueyBDBSR1RCBOU7q7yTcP 2l7A== 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=Ok7LAiocwziPNLnJTigNrjpE5FyHnTrBjoEWno2vU9A=; b=dF3WqlSHqWG6pk2+dveu3Bje93k10/qfMsTvaYfiZdV9jGoSbehQWFbSyoMTJ/6tut g0VRd1ueuJ2aUx+w+B+HjKpLKFCD8ytcUn3YazSolMvtJHMeBrCLVulnRnN2egRH6dVT Tj+qN6lN1332vjsJqKzvdH96uRi26ciREfkMVdLzH8iMXjoAkiiFtMtP2Rug+zWfyW14 SnlrEsDmkogUAh2kg6A4z4WiPc7c6Q3PIFsdvUXuwOc1fVxH4iAEMIWicbiMJsw0/wtp FIX1oAhiNVWRj5b16IGH9Gp6glrq2HDzTHOIQytLvLxApZiK2F0x63MH5iUz7Z1VD6ay D3nQ== X-Gm-Message-State: APjAAAW1Vo9slVsTHcKTpG4GvTgy5cHO4ExXR6PbcjyIIQYTdCXHrEQE mwBmaeqx0UMf/tLSdvCKygc= X-Google-Smtp-Source: APXvYqwFmSUbG9L1pqTdwfLWmXRXudIYGsPtwLkXHI7prpsDDVYiqtO6o/nHUAwzzYKt2F6BkNACOA== X-Received: by 2002:a65:6497:: with SMTP id e23mr2755586pgv.89.1561713383985; Fri, 28 Jun 2019 02:16:23 -0700 (PDT) Received: from localhost.localdomain ([203.100.54.194]) by smtp.gmail.com with ESMTPSA id x65sm1754521pfd.139.2019.06.28.02.16.19 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Fri, 28 Jun 2019 02:16:23 -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 09/30] locking/lockdep: Remove chain_head argument in validate_chain() Date: Fri, 28 Jun 2019 17:15:07 +0800 Message-Id: <20190628091528.17059-10-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 This argument says whether the chain is a head, meaning having just one lock, which can actually be tested by lock_chain->depth. So there is no need to explicitly make this argument, so remove it. No functional change. Signed-off-by: Yuyang Du --- kernel/locking/lockdep.c | 18 +++++++----------- 1 file changed, 7 insertions(+), 11 deletions(-) diff --git a/kernel/locking/lockdep.c b/kernel/locking/lockdep.c index 4ffb4df..e2ad673 100644 --- a/kernel/locking/lockdep.c +++ b/kernel/locking/lockdep.c @@ -2807,9 +2807,8 @@ static inline struct lock_chain *lookup_chain_cache(u64 chain_key) return add_chain_cache(curr, hlock, chain_key); } -static int validate_chain(struct task_struct *curr, - struct held_lock *hlock, - int chain_head, u64 chain_key) +static int validate_chain(struct task_struct *curr, struct held_lock *hlock, + u64 chain_key) { struct lock_chain *chain; /* @@ -2857,7 +2856,7 @@ static int validate_chain(struct task_struct *curr, * Add dependency only if this lock is not the head * of the chain, and if it's not a secondary read-lock: */ - if (!chain_head && ret != 2) { + if (chain->depth > 1 && ret != 2) { if (!check_prevs_add(curr, hlock, chain)) return 0; } @@ -2874,7 +2873,7 @@ static int validate_chain(struct task_struct *curr, #else static inline int validate_chain(struct task_struct *curr, struct held_lock *hlock, - int chain_head, u64 chain_key) + u64 chain_key) { return 1; } @@ -3707,7 +3706,6 @@ static int __lock_acquire(struct lockdep_map *lock, unsigned int subclass, struct lock_class *class = NULL; struct held_lock *hlock; unsigned int depth; - int chain_head = 0; int class_idx; u64 chain_key; @@ -3821,14 +3819,12 @@ static int __lock_acquire(struct lockdep_map *lock, unsigned int subclass, */ if (DEBUG_LOCKS_WARN_ON(chain_key != INITIAL_CHAIN_KEY)) return 0; - chain_head = 1; } hlock->prev_chain_key = chain_key; - if (separate_irq_context(curr, hlock)) { + if (separate_irq_context(curr, hlock)) chain_key = INITIAL_CHAIN_KEY; - chain_head = 1; - } + chain_key = iterate_chain_key(chain_key, class_idx); if (nest_lock && !__lock_is_held(nest_lock, -1)) { @@ -3841,7 +3837,7 @@ static int __lock_acquire(struct lockdep_map *lock, unsigned int subclass, WARN_ON_ONCE(!hlock_class(hlock)->key); } - if (!validate_chain(curr, hlock, chain_head, chain_key)) + if (!validate_chain(curr, hlock, chain_key)) return 0; curr->curr_chain_key = chain_key; -- 1.8.3.1