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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8850CC00140 for ; Sat, 13 Aug 2022 02:40:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237197AbiHMCku (ORCPT ); Fri, 12 Aug 2022 22:40:50 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39474 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229719AbiHMCkr (ORCPT ); Fri, 12 Aug 2022 22:40:47 -0400 Received: from bombadil.infradead.org (bombadil.infradead.org [IPv6:2607:7c80:54:3::133]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 99B908B99F for ; Fri, 12 Aug 2022 19:40:45 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20210309; h=Content-Transfer-Encoding: Content-Type:In-Reply-To:From:References:Cc:To:Subject:MIME-Version:Date: Message-ID:Sender:Reply-To:Content-ID:Content-Description; bh=BlfgV8HtMySJmFZBqWSSIw/CZQYPoON2S+sB6/la0Ss=; b=IOtl5eEv2dbGGfmqy4ESbweGsk EmJ8spyjKZ5Z3+tOna4Rom1FvW7AQPwFluzybL0GU7lqXN7rtELqExrGb3LrlcJ7254y9OF9xaivH g+if2+xiPIHiDhPIAuW94u4lkGeqjeAfPg7MD/cK96LXRkKdeNuFomQcpVppXlR36T6c+NHAAY38R hl6GreSwf2AwBzNCY4aP7EZi7+nvJYy+gdWwZ7z2Msx9g7rZ4fKTUQcDaF5rEpXR/w6dcIY+B2Byt VNXEpf883dtfi4BflLk+C79pv4a6+iBdaXslh1TRRf0XHgVQZ6hUbYlokM/W+NLKr+CCj5XEZpCUc 7GJ2TTpw==; Received: from [2601:1c0:6280:3f0::a6b3] by bombadil.infradead.org with esmtpsa (Exim 4.94.2 #2 (Red Hat Linux)) id 1oMh4e-003XS2-1z; Sat, 13 Aug 2022 02:40:28 +0000 Message-ID: Date: Fri, 12 Aug 2022 19:40:26 -0700 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:91.0) Gecko/20100101 Thunderbird/91.11.0 Subject: Re: [RFC PATCH v2 09/12] mm: Make MAX_ORDER of buddy allocator configurable via Kconfig SET_MAX_ORDER. Content-Language: en-US To: Zi Yan Cc: linux-mm@kvack.org, David Hildenbrand , Matthew Wilcox , Vlastimil Babka , "Kirill A . Shutemov" , Mike Kravetz , John Hubbard , Yang Shi , David Rientjes , James Houghton , Mike Rapoport , linux-kernel@vger.kernel.org References: <20220811231643.1012912-1-zi.yan@sent.com> <20220811231643.1012912-10-zi.yan@sent.com> <25D8229F-CFB1-46FE-B4C8-7D2EBEAB10AC@nvidia.com> From: Randy Dunlap In-Reply-To: <25D8229F-CFB1-46FE-B4C8-7D2EBEAB10AC@nvidia.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 8/12/22 19:37, Zi Yan wrote: > > On 12 Aug 2022, at 21:11, Randy Dunlap wrote: > >> Hi-- >> >> On 8/11/22 16:16, Zi Yan wrote: >> >>> diff --git a/mm/Kconfig b/mm/Kconfig >>> index bbe31e85afee..e558f5679707 100644 >>> --- a/mm/Kconfig >>> +++ b/mm/Kconfig >>> @@ -441,6 +441,20 @@ config SPARSEMEM_VMEMMAP >>> pfn_to_page and page_to_pfn operations. This is the most >>> efficient option when sufficient kernel resources are available. >>> >>> +config SET_MAX_ORDER >>> + int "Set maximum order of buddy allocator" >>> + depends on SPARSEMEM_VMEMMAP && (ARCH_FORCE_MAX_ORDER = 0) >>> + range 10 255 >>> + default "10" >>> + help >>> + The kernel memory allocator divides physically contiguous memory >>> + blocks into "zones", where each zone is a power of two number of >>> + pages. This option selects the largest power of two that the kernel >>> + keeps in the memory allocator. If you need to allocate very large >>> + blocks of physically contiguous memory, then you may need to >>> + increase this value. A value of 10 means that the largest free memory >>> + block is 2^10 pages. >> >> Please make sure that all lines of help text are indented with one tab + 2 spaces, >> as specified in Documentation/process/coding-style.rst. > > I guess you mean the wrong indentation of "depends on" here, since all > the help text is correctly indented. Thanks. I fixed it locally. Oops, yes. Thanks. -- ~Randy