From patchwork Tue Jun 13 18:24:32 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: SeongJae Park X-Patchwork-Id: 13279151 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id EEA88EB64DA for ; Tue, 13 Jun 2023 18:25:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239278AbjFMSYn (ORCPT ); Tue, 13 Jun 2023 14:24:43 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58500 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239242AbjFMSYm (ORCPT ); Tue, 13 Jun 2023 14:24:42 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 17F30E41; Tue, 13 Jun 2023 11:24:41 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 9D23C62F59; Tue, 13 Jun 2023 18:24:40 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 78518C43331; Tue, 13 Jun 2023 18:24:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1686680680; bh=8QtwSYO8fDJCyX3Iukfsqd/4jzpKwmY5DKHH76v+mD8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=NLe1oDvvlDNZZOS+fcGdvyQGzbtGAu6o52EhnNihiyzLUr40EX0ESaFKJ+C8VUGm7 3B2ao510PdqLceIpEBAQHFLcjZDj+ibxFG7xGS2v0dddzUw3h9BDOlOh2aekouM0Nu 8nsaioUIkdfb8YTTx0QtWEsnKUwW++YXrqthph+T0P/yjJ2eynVkbejNRgItTykowt zbA5omcQSINpvyzkw4GpVzcHGp7DyKDrdU0DHhG+EsP9vghbx5JdekUGLUkIMmTQxY CzLuNzhTNlmKdzbqMJA2pAABmPikZJ6HKDqArYJF1d8BIAl7ySLIT4H3rHAUxInWDp 9J5JMtL7eFIzQ== From: SeongJae Park To: paulmck@kernel.org Cc: SeongJae Park , joel@joelfernandes.org, mmpgouride@gmail.com, corbet@lwn.net, rcu@vger.kernel.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v2 2/4] Docs/RCU/rculist_nulls: Assign 'obj' before use from the examples Date: Tue, 13 Jun 2023 18:24:32 +0000 Message-Id: <20230613182434.88317-3-sj@kernel.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20230613182434.88317-1-sj@kernel.org> References: <20230613182434.88317-1-sj@kernel.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: rcu@vger.kernel.org Lookup example code snippets in rculist_nulls.rst are using 'obj' without assignment. Fix the code to assign it properly. Signed-off-by: SeongJae Park Reviewed-by: Joel Fernandes (Google) --- Documentation/RCU/rculist_nulls.rst | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/Documentation/RCU/rculist_nulls.rst b/Documentation/RCU/rculist_nulls.rst index 253ecd869fc2..94a8bfe9f560 100644 --- a/Documentation/RCU/rculist_nulls.rst +++ b/Documentation/RCU/rculist_nulls.rst @@ -54,7 +54,7 @@ but a version with an additional memory barrier (smp_rmb()) struct hlist_node *node, *next; for (pos = rcu_dereference((head)->first); pos && ({ next = pos->next; smp_rmb(); prefetch(next); 1; }) && - ({ tpos = hlist_entry(pos, typeof(*tpos), member); 1; }); + ({ obj = hlist_entry(pos, typeof(*obj), member); 1; }); pos = rcu_dereference(next)) if (obj->key == key) return obj; @@ -66,7 +66,7 @@ And note the traditional hlist_for_each_entry_rcu() misses this smp_rmb():: struct hlist_node *node; for (pos = rcu_dereference((head)->first); pos && ({ prefetch(pos->next); 1; }) && - ({ tpos = hlist_entry(pos, typeof(*tpos), member); 1; }); + ({ obj = hlist_entry(pos, typeof(*obj), member); 1; }); pos = rcu_dereference(pos->next)) if (obj->key == key) return obj;