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 677C2C4321A for ; Fri, 28 Jun 2019 09:15:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3B68F208CB for ; Fri, 28 Jun 2019 09:15:59 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="g2fRjok0" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726773AbfF1JP6 (ORCPT ); Fri, 28 Jun 2019 05:15:58 -0400 Received: from mail-pf1-f194.google.com ([209.85.210.194]:44223 "EHLO mail-pf1-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726508AbfF1JP5 (ORCPT ); Fri, 28 Jun 2019 05:15:57 -0400 Received: by mail-pf1-f194.google.com with SMTP id t16so2652355pfe.11 for ; Fri, 28 Jun 2019 02:15:57 -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=LrejKXGQ1w0xv5dXMTolgVu6Mt2RPt99t9Zyghhmncc=; b=g2fRjok05T8sDhCGihSZhKC1VkmrQHJTG6puiIgFVoFjEj8ykJXoliOc+ljRzlCwkW Ek36iPrtwD/1+HqaBV6OSWBIIHg4/iCon7dNgxgnm1Z4u/BuytWNBrjEndydGTJ9vPll iidA99nMyOerR3WhwYAt4TlZf5/XbR9pkIjtWf5B6/R8aTi/8ZArDdsRHcepVDJHZ2KD 5y76EhzMLzIcEq/DCpycqxJ9ybbF1/QMBuTaDJuE3GaSBzDk+UrqWm3qrIkrgkRpnTcY hXiH66NxIMJl5uAPr11ZOxtk+3IKRiuSTgoT7jOZN3aKODngdKjnqBqlDCUgfzicWAie F26A== 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=LrejKXGQ1w0xv5dXMTolgVu6Mt2RPt99t9Zyghhmncc=; b=YRjCcxXt6GeRV711YVwWW6d2ni6CBiyg1+w8T/26uTwJlvfW/itoqBS+u5i80iIJjX Vd8upstTKvKqEYd8BZrSHMANpG1d/+a8yUPDzSXqCBDIhlKKn3FkXG5Ihh39jK9pH/ni wtsdHaNS403tb6N7mCDVn3ZTzrVXBtC+s3CuT6CidCgxpMM5IIVkInsJlHdTAwPORq9u W1RZuf8WiP8CKV5geytXk/jEOReGD7tnNIHPESzqG+tCY6KaepuSr+AFJuvnf23etRzm zjJ74wmzZgGpxkQ5Wi6XxLESxYwM2qISpY/FT1iUJobWJ5DLxUM8M3K0GFgx3MB32RJF 6AXg== X-Gm-Message-State: APjAAAVTaAPuIXr6oDesp6TtHLuADt9nRIIu5A/OeBeI+MgpTT2wL5a9 +RFUoRQxPEjXpjYrLgVbgZjhHtd+315+CQ== X-Google-Smtp-Source: APXvYqw0Nz6jfkTZJobyFuFwTQ9cxrzjr6F1Lbl60NGul9fCc6CBo6261mSlRHSSK2y5ylQgb/1Tzg== X-Received: by 2002:a63:6843:: with SMTP id d64mr991072pgc.383.1561713357112; Fri, 28 Jun 2019 02:15:57 -0700 (PDT) Received: from localhost.localdomain ([203.100.54.194]) by smtp.gmail.com with ESMTPSA id x65sm1754521pfd.139.2019.06.28.02.15.52 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Fri, 28 Jun 2019 02:15:56 -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 03/30] locking/lockdep: Change return type of lookup_chain_cache_add() Date: Fri, 28 Jun 2019 17:15:01 +0800 Message-Id: <20190628091528.17059-4-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 Like the previous change, the function lookup_chain_cache_add() returns the pointer of the lock chain if the chain is new. No functional change. Signed-off-by: Yuyang Du --- kernel/locking/lockdep.c | 23 ++++++++++------------- 1 file changed, 10 insertions(+), 13 deletions(-) diff --git a/kernel/locking/lockdep.c b/kernel/locking/lockdep.c index 3546894..d545b6c 100644 --- a/kernel/locking/lockdep.c +++ b/kernel/locking/lockdep.c @@ -2796,13 +2796,13 @@ static inline struct lock_chain *lookup_chain_cache(u64 chain_key) /* * If the key is not present yet in dependency chain cache then - * add it and return 1 - in this case the new dependency chain is - * validated. If the key is already hashed, return 0. - * (On return with 1 graph_lock is held.) + * add it and return the chain - in this case the new dependency + * chain will be validated. If the key is already hashed, return + * NULL. (On return with the new chain graph_lock is held.) */ -static inline int lookup_chain_cache_add(struct task_struct *curr, - struct held_lock *hlock, - u64 chain_key) +static inline struct lock_chain * +lookup_chain_cache_add(struct task_struct *curr, struct held_lock *hlock, + u64 chain_key) { struct lock_class *class = hlock_class(hlock); struct lock_chain *chain = lookup_chain_cache(chain_key); @@ -2810,7 +2810,7 @@ static inline int lookup_chain_cache_add(struct task_struct *curr, if (chain) { cache_hit: if (!check_no_collision(curr, hlock, chain)) - return 0; + return NULL; if (very_verbose(class)) { printk("\nhash chain already cached, key: " @@ -2819,7 +2819,7 @@ static inline int lookup_chain_cache_add(struct task_struct *curr, class->key, class->name); } - return 0; + return NULL; } if (very_verbose(class)) { @@ -2828,7 +2828,7 @@ static inline int lookup_chain_cache_add(struct task_struct *curr, } if (!graph_lock()) - return 0; + return NULL; /* * We have to walk the chain again locked - to avoid duplicates: @@ -2839,10 +2839,7 @@ static inline int lookup_chain_cache_add(struct task_struct *curr, goto cache_hit; } - if (!add_chain_cache(curr, hlock, chain_key)) - return 0; - - return 1; + return add_chain_cache(curr, hlock, chain_key); } static int validate_chain(struct task_struct *curr, -- 1.8.3.1