Received: by 2002:a25:4158:0:0:0:0:0 with SMTP id o85csp2441481yba; Sun, 7 Apr 2019 19:13:53 -0700 (PDT) X-Google-Smtp-Source: APXvYqz5w5W9ZieXZZp3YMPamYYLYlOxx5e+YduLiMVqnvMSS54PSQy61xHgXTOrQc0FH3zhq3L9 X-Received: by 2002:a17:902:b706:: with SMTP id d6mr27416735pls.250.1554689633059; Sun, 07 Apr 2019 19:13:53 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1554689633; cv=none; d=google.com; s=arc-20160816; b=fCZchUSCcJIuhuNwlZgufMHyEbU3YCREPDbLqxcIqh9cYcVBjCTKaF0EGot/gSQtLy 8giy1gZ+UG7C6jQQNK4QtER/6DuMoldtB1KGkOe4YrR4CHeiuKJh+ICI/1AaxYxIFLuL JyQl2cMCxaoqlwUnWMH8uw9ecXzRSbk4nMmyrx+cUxoSonb+2IHU4ug8nMbrH9jzgXl1 FFIqmtMaCa38fSbcqPa7KvPA1VOnKhE/oaYk0apkfTplRsKF2L4q9sIU/shyjOoXt4mZ rh0uzhzFz3f0F8huZJcZks5jZfGvCIxDaEjA7SPKeKksPC7mvSfh+6I9bDKvA46XEH70 IAcQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:sender:content-transfer-encoding:mime-version :references:in-reply-to:from:subject:cc:to:message-id:date; bh=zi8SZwFArWqIZbyMxbRQMeuAv1FVEZN80v+7lmnAUVs=; b=TPvDof3Mm9iahCx3HL0yH2lO/pzcm0guucl7qttU/p3pgfj9HYxYa+oJ36kOPbs1fd LKNAHnXoMfw16decUzQ4lq3RukcmVBv+2pn5ob/gN+8YSy2XPh6iQrESY9gETxD5UCeh UqQMEmmT66JT8MR6kZT7xg8O0gYkXfcvERWRNlo54KZ6VrnFNj6Ey2SJdelgJhNFmYCn iaMuD7pgW2GlNgI6W0a4fzFEogowf42LIXjBkrb594We06sLERvqTngLpq0va9okrgyx 7l9i/w64wJJZuYG1/f/3Ocvf+g/U88z7RgKTJgNae+DRKZOfkc1scKjznbO1AITAi7bK CCBQ== ARC-Authentication-Results: i=1; mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Return-Path: Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67]) by mx.google.com with ESMTP id q13si25717484pfi.208.2019.04.07.19.13.36; Sun, 07 Apr 2019 19:13:53 -0700 (PDT) Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67; Authentication-Results: mx.google.com; spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726547AbfDHCM7 (ORCPT + 99 others); Sun, 7 Apr 2019 22:12:59 -0400 Received: from shards.monkeyblade.net ([23.128.96.9]:55824 "EHLO shards.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726461AbfDHCM6 (ORCPT ); Sun, 7 Apr 2019 22:12:58 -0400 Received: from localhost (unknown [IPv6:2601:601:9f80:35cd::d71]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (Client did not present a certificate) (Authenticated sender: davem-davemloft) by shards.monkeyblade.net (Postfix) with ESMTPSA id 2D197133E976D; Sun, 7 Apr 2019 19:12:58 -0700 (PDT) Date: Sun, 07 Apr 2019 19:12:55 -0700 (PDT) Message-Id: <20190407.191255.1243683680105907349.davem@davemloft.net> To: neilb@suse.com Cc: tgraf@suug.ch, herbert@gondor.apana.org.au, netdev@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 0/4 v2] Convert rhashtable to use bitlocks From: David Miller In-Reply-To: <155416000985.9540.14182958463813560577.stgit@noble.brown> References: <155416000985.9540.14182958463813560577.stgit@noble.brown> X-Mailer: Mew version 6.8 on Emacs 26.1 Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-Greylist: Sender succeeded SMTP AUTH, not delayed by milter-greylist-4.5.12 (shards.monkeyblade.net [149.20.54.216]); Sun, 07 Apr 2019 19:12:58 -0700 (PDT) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: NeilBrown Date: Tue, 02 Apr 2019 10:07:45 +1100 > This series converts rhashtable to use a per-bucket bitlock > rather than a separate array of spinlocks. > This: > reduces memory usage > results in slightly fewer memory accesses > slightly improves parallelism > makes a configuration option unnecessary > > The main change from previous version is to use a distinct type for > the pointer in the bucket which has a bit-lock in it. This > helped find two places where rht_ptr() was missed, one > in rhashtable_free_and_destroy() in print_ht in the test code. This looks good to me and I haven't seen any major objections. I think however the thing is encoded, an unsigned long or a pointer, the cleanliness is basically a wash. Thanks.