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=-7.5 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 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 49A33C43381 for ; Mon, 15 Mar 2021 12:26:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id ACF7764E89 for ; Mon, 15 Mar 2021 12:26:54 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229585AbhCOM0Z (ORCPT ); Mon, 15 Mar 2021 08:26:25 -0400 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:55758 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229696AbhCOM0I (ORCPT ); Mon, 15 Mar 2021 08:26:08 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1615811168; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=BN3J83lgEQDDF6GxaX9y5aWAfYv6V2YaybS0wCx0hT0=; b=N8EmnouDBSt1k7IT+TUMLwkyFPfjGDQZxAqrd3lat1o7J6PuLzUSj8Ettfi0rrsa7szu1X lYNIB7zYQvniW34W9nCnMkb1h8xAT2TRqTPDTgd8BGisBU4JYGysm1blKx7Facnn9KbR0y 5Q0An/Y+bhoMj6aztjlXdQBfU6kz6CQ= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-273-1VYrYoYjORCC5akzOPfb_A-1; Mon, 15 Mar 2021 08:26:04 -0400 X-MC-Unique: 1VYrYoYjORCC5akzOPfb_A-1 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id D8F62801817; Mon, 15 Mar 2021 12:25:59 +0000 (UTC) Received: from [10.36.112.200] (ovpn-112-200.ams2.redhat.com [10.36.112.200]) by smtp.corp.redhat.com (Postfix) with ESMTP id CC1A560CEF; Mon, 15 Mar 2021 12:25:41 +0000 (UTC) Subject: Re: [PATCH RFCv2] mm/madvise: introduce MADV_POPULATE_(READ|WRITE) to prefault/prealloc memory To: "Kirill A. Shutemov" Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, Andrew Morton , Arnd Bergmann , Michal Hocko , Oscar Salvador , Matthew Wilcox , Andrea Arcangeli , Minchan Kim , Jann Horn , Jason Gunthorpe , Dave Hansen , Hugh Dickins , Rik van Riel , "Michael S . Tsirkin" , "Kirill A . Shutemov" , Vlastimil Babka , Richard Henderson , Ivan Kokshaysky , Matt Turner , Thomas Bogendoerfer , "James E.J. Bottomley" , Helge Deller , Chris Zankel , Max Filippov , Mike Kravetz , Peter Xu , Rolf Eike Beer , linux-alpha@vger.kernel.org, linux-mips@vger.kernel.org, linux-parisc@vger.kernel.org, linux-xtensa@linux-xtensa.org, linux-arch@vger.kernel.org, Linux API References: <20210308164520.18323-1-david@redhat.com> <20210315122213.k52wtlbbhsw42pks@box> From: David Hildenbrand Organization: Red Hat GmbH Message-ID: <7d607d1c-efd5-3888-39bb-9e5f8bc08185@redhat.com> Date: Mon, 15 Mar 2021 13:25:40 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.8.0 MIME-Version: 1.0 In-Reply-To: <20210315122213.k52wtlbbhsw42pks@box> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 Precedence: bulk List-ID: X-Mailing-List: linux-parisc@vger.kernel.org On 15.03.21 13:22, Kirill A. Shutemov wrote: > On Mon, Mar 08, 2021 at 05:45:20PM +0100, David Hildenbrand wrote: >> + case -EHWPOISON: /* Skip over any poisoned pages. */ >> + start += PAGE_SIZE; >> + continue; > > Why is it good approach? It's not abvious to me. My main motivation was to simplify return code handling. I don't want to return -EHWPOISON to user space and I don't want to convert it into something misleading like -ENOMEM or -EINVAL. So I decided to handle such stuff internally. What would be you take on that? -- Thanks, David / dhildenb From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Hildenbrand Subject: Re: [PATCH RFCv2] mm/madvise: introduce MADV_POPULATE_(READ|WRITE) to prefault/prealloc memory Date: Mon, 15 Mar 2021 13:25:40 +0100 Message-ID: <7d607d1c-efd5-3888-39bb-9e5f8bc08185@redhat.com> References: <20210308164520.18323-1-david@redhat.com> <20210315122213.k52wtlbbhsw42pks@box> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Return-path: DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1615811166; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=BN3J83lgEQDDF6GxaX9y5aWAfYv6V2YaybS0wCx0hT0=; b=ORPnbIw4JBEFygYEjoyZZRXBZulwVihhCTQvaWWknESfMNrt+P1d4Jro9R2uCANuz/5+Oj KapuDSk3BOxcI70CuqkeEPYVILgsxo8ambLYHuf6Sr7ag7RqbZ10VX6vBr16YEXK+VFeM5 vAySpjo0rXa/J+eISZxZSoMf0Yn6txE= In-Reply-To: <20210315122213.k52wtlbbhsw42pks@box> Content-Language: en-US List-ID: Content-Type: text/plain; charset="us-ascii"; format="flowed" To: "Kirill A. Shutemov" Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, Andrew Morton , Arnd Bergmann , Michal Hocko , Oscar Salvador , Matthew Wilcox , Andrea Arcangeli , Minchan Kim , Jann Horn , Jason Gunthorpe , Dave Hansen , Hugh Dickins , Rik van Riel , "Michael S . Tsirkin" , "Kirill A . Shutemov" , Vlastimil Babka , Richard Henderson , Ivan Kokshaysky , Matt Turner , Thomas Bogendoerfer On 15.03.21 13:22, Kirill A. Shutemov wrote: > On Mon, Mar 08, 2021 at 05:45:20PM +0100, David Hildenbrand wrote: >> + case -EHWPOISON: /* Skip over any poisoned pages. */ >> + start += PAGE_SIZE; >> + continue; > > Why is it good approach? It's not abvious to me. My main motivation was to simplify return code handling. I don't want to return -EHWPOISON to user space and I don't want to convert it into something misleading like -ENOMEM or -EINVAL. So I decided to handle such stuff internally. What would be you take on that? -- Thanks, David / dhildenb