From patchwork Fri Jun 16 23:36:24 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: SeongJae Park X-Patchwork-Id: 109387 Return-Path: Delivered-To: ouuuleilei@gmail.com Received: by 2002:a59:994d:0:b0:3d9:f83d:47d9 with SMTP id k13csp1684716vqr; Fri, 16 Jun 2023 16:50:14 -0700 (PDT) X-Google-Smtp-Source: ACHHUZ7F4jWx1y2RPa95V8mHw6amgSvFqaGLIROSUC2JLAKbxRf8KgL88vc/0ks2JjA7IUc5osyl X-Received: by 2002:a05:6a20:c789:b0:11e:18e:a105 with SMTP id hk9-20020a056a20c78900b0011e018ea105mr3887871pzb.55.1686959414351; Fri, 16 Jun 2023 16:50:14 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1686959414; cv=none; d=google.com; s=arc-20160816; b=nIoinF7er+QpwptWC0Izae7jkCZSkOgNUWFAb2VE/aGF7ToKk/Um3W+hhfyPS79Yuo WZh98J+JutC/PrfSHSisSbb6uoRjvGdnDOIQGdz5rU/Tn7dKDQgvjL1cGC2em9KWsTtW WxvA+rkj1siHkd5Rcf7MiNmYLhczqEEmgMMycH9/BgLyJ3tSJCDclETA2k8hlc0AXjjU +JpnKMDMhv3N6pISezdq9qaJJHyTyP0y7jZPGAxKUE41HxO7tl5Z2f+hdG5djmQ/mZe4 2L/7SUCsrKhbbVuVr7snR+i20XJUx/jWDtFv+43z/BTgrFlG01Pu34h+pXOhWYf7s2PL PyBA== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:content-transfer-encoding:mime-version :references:in-reply-to:message-id:date:subject:cc:to:from :dkim-signature; bh=XXCKgMDYCTj1E8kXvTitG6SOSFZXS8oJj7piZVXs/rc=; b=uEJG2ObZcpVrpZz/cHkrbOluDlmEtbcbSiaMO7VevTMutiD8hwYXUC+nHvixsFRQ0c DG2/y/69SKQLkNn/OP0v7BVBqMJCTkktpK5yPkSJmv25bm1ps4y+9JXsr5G4OGWoD/8C epPrvExlxTJyMGD9v7K8YtaBspxZp6eysMaaEOg1fwOseOCPLzrFyuuMhG20VjKxl/CI WoZShnxtJr3s8uOmCQnmeB1Zus45m0qikBb6UoudTzF9oo7xFcEHDAdtAV8WKKtVDVoY YX5zIUjuHZSFM2ST/lxfO2U8nFCTaiLbyAxgwkhwSVXOeXqitB7VG7nQIWHwmDcDh1IO BCNQ== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@kernel.org header.s=k20201202 header.b=K6iOOxAI; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=kernel.org Received: from out1.vger.email (out1.vger.email. [2620:137:e000::1:20]) by mx.google.com with ESMTP id l186-20020a6388c3000000b0054fe20a34b2si5721617pgd.850.2023.06.16.16.49.58; Fri, 16 Jun 2023 16:50:14 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20; Authentication-Results: mx.google.com; dkim=pass header.i=@kernel.org header.s=k20201202 header.b=K6iOOxAI; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1345775AbjFPXgk (ORCPT + 99 others); Fri, 16 Jun 2023 19:36:40 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49318 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1345777AbjFPXgg (ORCPT ); Fri, 16 Jun 2023 19:36:36 -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 5D03A3AB3; Fri, 16 Jun 2023 16:36:33 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id E69B9623C4; Fri, 16 Jun 2023 23:36:32 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id B90E3C433C8; Fri, 16 Jun 2023 23:36:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1686958592; bh=Lcfm0OdItYB2zZ/FXd8OC9BkWFuELqxJlr2ec9I0ACI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=K6iOOxAImFvfzsq3NLrXc9ruXfxNGqrgXYH/eyLxngnCVEL/jmDC9OccFZ+RLMrxa w2+woDg/eqFXS1GB2sBBnxNNxId+ZvRFFuUx7wQANr64cj/vKQjQGbMIGJxjU3alTW 0wPb8+l+ldF5OEFSQF6pkL/EcaP6utn7hcSIZyrZCcRdQ3zrywjt5hQhBoA31Tm3DZ oVG8wbkw+e5fqOXDDEc5CUFJ/XWRyipqd7UdboPEldHvjky6zBg6RfG0uWQ2xC5i9p 7/q6qsgdXlXL1k73LYccPkm3fFVF20Z76QevEhsR+2KUAsbkyFqx2KZCgrAE+2rjHQ cFj6tqhkRHuKg== 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 v4 1/3] Docs/RCU/rculist_nulls: Specify type of the object in examples Date: Fri, 16 Jun 2023 23:36:24 +0000 Message-Id: <20230616233626.83906-2-sj@kernel.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20230616233626.83906-1-sj@kernel.org> References: <20230616233626.83906-1-sj@kernel.org> MIME-Version: 1.0 X-Spam-Status: No, score=-4.4 required=5.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,RCVD_IN_DNSWL_MED, SPF_HELO_NONE,SPF_PASS,T_SCC_BODY_TEXT_LINE autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org X-getmail-retrieved-from-mailbox: =?utf-8?q?INBOX?= X-GMAIL-THRID: =?utf-8?q?1768905154872231837?= X-GMAIL-MSGID: =?utf-8?q?1768905154872231837?= The type of 'obj' in example code of rculist_nulls.rst is implicit. Provide the specific type of it before the example code. Suggested-by: Paul E. McKenney Link: https://lore.kernel.org/rcu/43943609-f80c-4b6a-9844-994eef800757@paulmck-laptop/ Signed-off-by: SeongJae Park --- Documentation/RCU/rculist_nulls.rst | 14 +++++++++++++- 1 file changed, 13 insertions(+), 1 deletion(-) diff --git a/Documentation/RCU/rculist_nulls.rst b/Documentation/RCU/rculist_nulls.rst index 94a8bfe9f560..a6827cc31791 100644 --- a/Documentation/RCU/rculist_nulls.rst +++ b/Documentation/RCU/rculist_nulls.rst @@ -18,7 +18,16 @@ to solve following problem. Without 'nulls', a typical RCU linked list managing objects which are allocated with SLAB_TYPESAFE_BY_RCU kmem_cache can use the following -algorithms: +algorithms. Following examples assume 'obj' is a pointer to such +objects, which is having below type. + +:: + + struct object { + struct hlist_node obj_node; + atomic_t refcnt; + unsigned int key; + }; 1) Lookup algorithm ------------------- @@ -142,6 +151,9 @@ the beginning. If the object was moved to the same chain, then the reader doesn't care: It might occasionally scan the list again without harm. +Note that using hlist_nulls means the type of 'obj_node' field of +'struct object' becomes 'struct hlist_nulls_node'. + 1) lookup algorithm -------------------