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=-18.3 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, USER_IN_DEF_DKIM_WL autolearn=unavailable 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 30ECDC433E0 for ; Sun, 31 Jan 2021 01:11:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id F0E1564E19 for ; Sun, 31 Jan 2021 01:11:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232274AbhAaBLV (ORCPT ); Sat, 30 Jan 2021 20:11:21 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33556 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230360AbhAaBLU (ORCPT ); Sat, 30 Jan 2021 20:11:20 -0500 Received: from mail-pf1-x42b.google.com (mail-pf1-x42b.google.com [IPv6:2607:f8b0:4864:20::42b]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 314A5C061573 for ; Sat, 30 Jan 2021 17:10:40 -0800 (PST) Received: by mail-pf1-x42b.google.com with SMTP id i63so9106861pfg.7 for ; Sat, 30 Jan 2021 17:10:40 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:from:to:cc:subject:in-reply-to:message-id:references :mime-version; bh=WnnqcWCxinzE2IIXfwW8B1NU0qXZbP2tW/76Rc4KOfQ=; b=PEIyRHsPXymEddhifnCMfnXCpz7yq5ShKa7hWqXJejwLaaoiK7h2FEEnt4o7SGbdJJ zZ8cGCyQKrJLSbros9s+PFp7n00Xj7rqSMfrfzx4tgg0dXCn7puM+OL2jpqimmSmzJy4 +qpUqOd4llseW9R8Af2w4TrCoDJ4X9qVZgs5Krr4PGenY326GMu8wX1EHADNPAQmbeC7 kGrK/7PgQF9q84e+HAw6h3aKtwm3+TwxG5nA7EJN/40xxb4zzvsku9dEeZ9gJ57M1q/K +Jf8sTPdR1bKtyoUHg5ahUh8GocPQiELvkf6nXI12+oHIu909sMXFpsoJXshtuXfV6MQ Y4yw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:in-reply-to:message-id :references:mime-version; bh=WnnqcWCxinzE2IIXfwW8B1NU0qXZbP2tW/76Rc4KOfQ=; b=mWBxpPKjBxYqiIPAH+Qg5M1khJN3Yj93xOA/bGDDJfIaTA2deX6uWO/Xm1HwkbrB5u ooXQCSxnnN7VK3fDjG9NV6YxaIalGv1LfDIr6Q2pyOmi02rcbpuiNmH7pN09gOkuOy7i c3TkMkO0ndpvPQFrGUpWwCOrgIeLFRnApBnn2gVyL63Nl0pdz2QpIeLfJCyFM9GBMyVl dxQZHI3GUmpsnbx4PqwHjlc+iS6Kc+Zd5KV42FGXsFCTbXPc6yNJAoNq0jIFaPSzccK8 WO//BuKiFOh6JdoDk0wD81wsvL4wx5eplR8Rah7Sfb5aD+pYF8iGKS6K8E7x+h+H+ZGN msZg== X-Gm-Message-State: AOAM532K4QY9OkMSEFwsqGJzA/wCEXlOVjjp3BrcRe7k8vheGfGDBhM/ bTQTxdQHvBuEkFcRw49GvTJ+IQ== X-Google-Smtp-Source: ABdhPJz+krmbNOjAh3xBgN4aIa4YeB3SrGwyAxX3AqsZT6+jYbJrjCFSAAitddf2O9BKhKl6gDq0GQ== X-Received: by 2002:a63:4e08:: with SMTP id c8mr10404489pgb.87.1612055439683; Sat, 30 Jan 2021 17:10:39 -0800 (PST) Received: from [2620:15c:17:3:4a0f:cfff:fe51:6667] ([2620:15c:17:3:4a0f:cfff:fe51:6667]) by smtp.gmail.com with ESMTPSA id q79sm14369850pfc.63.2021.01.30.17.10.38 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sat, 30 Jan 2021 17:10:38 -0800 (PST) Date: Sat, 30 Jan 2021 17:10:37 -0800 (PST) From: David Rientjes To: Dave Hansen cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, ben.widawsky@intel.com, cl@linux.com, alex.shi@linux.alibaba.com, tobin@kernel.org, akpm@linux-foundation.org, ying.huang@intel.com, dan.j.williams@intel.com, cai@lca.pw, dwagner@suse.de, osalvador@suse.de Subject: Re: [RFC][PATCH 03/13] mm/vmscan: replace implicit RECLAIM_ZONE checks with explicit checks In-Reply-To: <20210126003417.72B4BCFB@viggo.jf.intel.com> Message-ID: <4ea95a1a-33b0-eb15-98d8-79c81dc8a37@google.com> References: <20210126003411.2AC51464@viggo.jf.intel.com> <20210126003417.72B4BCFB@viggo.jf.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 25 Jan 2021, Dave Hansen wrote: > > From: Dave Hansen > > RECLAIM_ZONE was assumed to be unused because it was never explicitly > used in the kernel. However, there were a number of places where it > was checked implicitly by checking 'node_reclaim_mode' for a zero > value. > > These zero checks are not great because it is not obvious what a zero > mode *means* in the code. Replace them with a helper which makes it > more obvious: node_reclaim_enabled(). > > This helper also provides a handy place to explicitly check the > RECLAIM_ZONE bit itself. Check it explicitly there to make it more > obvious where the bit can affect behavior. > > This should have no functional impact. > > Signed-off-by: Dave Hansen > Reviewed-by: Ben Widawsky > Acked-by: Christoph Lameter > Cc: Alex Shi > Cc: "Tobin C. Harding" > Cc: Christoph Lameter > Cc: Andrew Morton > Cc: Huang Ying > Cc: Dan Williams > Cc: Qian Cai > Cc: Daniel Wagner > Cc: osalvador Acked-by: David Rientjes