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=-3.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED autolearn=no 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 2B89EC4361B for ; Thu, 17 Dec 2020 10:43:27 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C65EE2388E for ; Thu, 17 Dec 2020 10:43:26 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727755AbgLQKn0 (ORCPT ); Thu, 17 Dec 2020 05:43:26 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57746 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726160AbgLQKnZ (ORCPT ); Thu, 17 Dec 2020 05:43:25 -0500 Received: from mail-pf1-x42d.google.com (mail-pf1-x42d.google.com [IPv6:2607:f8b0:4864:20::42d]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A3124C0617B0 for ; Thu, 17 Dec 2020 02:42:39 -0800 (PST) Received: by mail-pf1-x42d.google.com with SMTP id q22so18757617pfk.12 for ; Thu, 17 Dec 2020 02:42:39 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bytedance-com.20150623.gappssmtp.com; s=20150623; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=1ISaOxv2M3y6rzTF7V0ZUu/XvyKLY1Lh8tc0RjKV/bE=; b=JdIliH6SeXTydvTW28vuoACmBG9WQrqrb7eKRimd1Cl9Rh8HMO0wnx7XJRZaA7s0sN dgXttyNW31CGIl4D9+NBOs8ygxpG55qZVW0OepUVtuNnw3MCLFVAP8MXJfyAaEmEMArH ud1l8hYWYRDL5TTsIuEMt8tTHpvlXlQG80iRvj6OkWGBKjMjpHnHEcRqFIr6t4P4hGRg 92iWo0ce2iAyOZv/ULkYH33m4ThMTdyKMzWezF9P85dqlZkW/btdOv1Jfr18pK85a3JX DuIGt2ihK02S2meZ+b1yNUwpJafxowwwPbj1PT3Hc/3fWv9yv5zlIYE8AG2IVjjmPq/N XxFw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=1ISaOxv2M3y6rzTF7V0ZUu/XvyKLY1Lh8tc0RjKV/bE=; b=HmKCj88KuwzI5dpEUEPeGkb+927hy3DkhfSgh7iZOwXT2wR5h2QMET4MF8Jk9Ds5+P VGKBE5LtHNlELfSyVuAOy+tz7eFz7TLBXy1BtiTGcB4QB9uQdOpdtGXrsqmrJAldjIJr ZqdhMzrMpbJ6baCt11wlNpGvt7PM2ugzXpN/Mc/s6i9utQgBG6odq2mOHjmnsJKiEuIB wzm+0e1zfQ0gmg88LC/OeLH1qjw6DMkQEnckpMOVRw+ieJM1zRvyonWyRwapFuZ9CYQi H9T7OCgP6NsrAAE+JRdMYvrYz38MvY4lu9em0ddOYAhmbiwNGR8tEGk1dIk1+C7+PqU+ 6VCQ== X-Gm-Message-State: AOAM5328tkIEWud7vXS7qD88bBbVrc6cq5hlxG6y0YANFZPljelBW0C6 wgV+olqTTdoOggcD3948p4d8QVwkQmyS0HiyBCabPA== X-Google-Smtp-Source: ABdhPJyQqONmSuuKMNSnMEKXcxXk9UVbNjaPbYGZ8ABrFQ0kIzVpoir8YmisZWEI9RBFKOOPGshygmfRmOp3NTZUEXA= X-Received: by 2002:a63:50a:: with SMTP id 10mr9159315pgf.273.1608201758996; Thu, 17 Dec 2020 02:42:38 -0800 (PST) MIME-Version: 1.0 References: <20201213154534.54826-1-songmuchun@bytedance.com> <20201213154534.54826-12-songmuchun@bytedance.com> <20201217103154.GA8481@linux> In-Reply-To: <20201217103154.GA8481@linux> From: Muchun Song Date: Thu, 17 Dec 2020 18:42:02 +0800 Message-ID: Subject: Re: [External] Re: [PATCH v9 11/11] mm/hugetlb: Optimize the code with the help of the compiler To: Oscar Salvador Cc: Jonathan Corbet , Mike Kravetz , Thomas Gleixner , mingo@redhat.com, bp@alien8.de, x86@kernel.org, hpa@zytor.com, dave.hansen@linux.intel.com, luto@kernel.org, Peter Zijlstra , viro@zeniv.linux.org.uk, Andrew Morton , paulmck@kernel.org, mchehab+huawei@kernel.org, pawan.kumar.gupta@linux.intel.com, Randy Dunlap , oneukum@suse.com, anshuman.khandual@arm.com, jroedel@suse.de, Mina Almasry , David Rientjes , Matthew Wilcox , Michal Hocko , "Song Bao Hua (Barry Song)" , David Hildenbrand , Xiongchun duan , linux-doc@vger.kernel.org, LKML , Linux Memory Management List , linux-fsdevel Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org On Thu, Dec 17, 2020 at 6:32 PM Oscar Salvador wrote: > > On Sun, Dec 13, 2020 at 11:45:34PM +0800, Muchun Song wrote: > > static inline unsigned int free_vmemmap_pages_per_hpage(struct hstate *h) > > { > > - return h->nr_free_vmemmap_pages; > > + return h->nr_free_vmemmap_pages && is_power_of_2(sizeof(struct page)); > > This is wrong as it will return either true or false, but not what we want: Yeah, very thanks for pointing that out. > > static inline unsigned long free_vmemmap_pages_size_per_hpage(struct hstate *h) > { > return (unsigned long)free_vmemmap_pages_per_hpage(h) << PAGE_SHIFT; > } > > the above will compute to 4096, which is wrong for obvious reasons. You are right. It is my mistake. Thanks Oscar. > > -- > Oscar Salvador > SUSE L3 -- Yours, Muchun