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=-2.4 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, 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 2A2F0C3F2D1 for ; Mon, 2 Mar 2020 14:17:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E8D952173E for ; Mon, 2 Mar 2020 14:17:56 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="WG/2WBrb" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727209AbgCBORz (ORCPT ); Mon, 2 Mar 2020 09:17:55 -0500 Received: from us-smtp-delivery-1.mimecast.com ([205.139.110.120]:20302 "EHLO us-smtp-1.mimecast.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1727159AbgCBORy (ORCPT ); Mon, 2 Mar 2020 09:17:54 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1583158672; 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:autocrypt:autocrypt; bh=aSlbqTfXB8KK40C4UbS0ygfhPT9hTLVPTl4nVXr8U48=; b=WG/2WBrbf7lPNY5fvHa+BZo+XNIS8hra5g6m6R0qHrP9g3dbONuCd1Wfaivp+FE5rWsaV+ ebLTR44IpPcFR3LXgLphstSg3uskGFfrad7BwP6BDSpb1ewO5j2u47+HVxtXSJ0VQpOb07 uCfIRdJxqI6AWLnLCLnUnjIPxok0sOo= 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-360-cJl0n0beP5iUYhC6PrB-kA-1; Mon, 02 Mar 2020 09:17:50 -0500 X-MC-Unique: cJl0n0beP5iUYhC6PrB-kA-1 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id CBBE1190B2D3; Mon, 2 Mar 2020 14:17:47 +0000 (UTC) Received: from [10.36.116.114] (ovpn-116-114.ams2.redhat.com [10.36.116.114]) by smtp.corp.redhat.com (Postfix) with ESMTP id BB7CD60C80; Mon, 2 Mar 2020 14:17:39 +0000 (UTC) Subject: Re: [PATCH v1 04/11] mm: Export alloc_contig_range() / free_contig_range() To: Michal Hocko Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, virtio-dev@lists.oasis-open.org, virtualization@lists.linux-foundation.org, kvm@vger.kernel.org, Andrew Morton , "Michael S . Tsirkin" , Vlastimil Babka , Oscar Salvador , Mel Gorman , Mike Rapoport , Dan Williams , Alexander Duyck , Pavel Tatashin , Alexander Potapenko References: <20200302134941.315212-1-david@redhat.com> <20200302134941.315212-5-david@redhat.com> <20200302140519.GN4380@dhcp22.suse.cz> From: David Hildenbrand Autocrypt: addr=david@redhat.com; prefer-encrypt=mutual; keydata= mQINBFXLn5EBEAC+zYvAFJxCBY9Tr1xZgcESmxVNI/0ffzE/ZQOiHJl6mGkmA1R7/uUpiCjJ dBrn+lhhOYjjNefFQou6478faXE6o2AhmebqT4KiQoUQFV4R7y1KMEKoSyy8hQaK1umALTdL QZLQMzNE74ap+GDK0wnacPQFpcG1AE9RMq3aeErY5tujekBS32jfC/7AnH7I0v1v1TbbK3Gp XNeiN4QroO+5qaSr0ID2sz5jtBLRb15RMre27E1ImpaIv2Jw8NJgW0k/D1RyKCwaTsgRdwuK Kx/Y91XuSBdz0uOyU/S8kM1+ag0wvsGlpBVxRR/xw/E8M7TEwuCZQArqqTCmkG6HGcXFT0V9 PXFNNgV5jXMQRwU0O/ztJIQqsE5LsUomE//bLwzj9IVsaQpKDqW6TAPjcdBDPLHvriq7kGjt WhVhdl0qEYB8lkBEU7V2Yb+SYhmhpDrti9Fq1EsmhiHSkxJcGREoMK/63r9WLZYI3+4W2rAc UucZa4OT27U5ZISjNg3Ev0rxU5UH2/pT4wJCfxwocmqaRr6UYmrtZmND89X0KigoFD/XSeVv jwBRNjPAubK9/k5NoRrYqztM9W6sJqrH8+UWZ1Idd/DdmogJh0gNC0+N42Za9yBRURfIdKSb B3JfpUqcWwE7vUaYrHG1nw54pLUoPG6sAA7Mehl3nd4pZUALHwARAQABtCREYXZpZCBIaWxk ZW5icmFuZCA8ZGF2aWRAcmVkaGF0LmNvbT6JAlgEEwEIAEICGwMFCQlmAYAGCwkIBwMCBhUI AgkKCwQWAgMBAh4BAheAFiEEG9nKrXNcTDpGDfzKTd4Q9wD/g1oFAl3pImkCGQEACgkQTd4Q 9wD/g1o+VA//SFvIHUAvul05u6wKv/pIR6aICPdpF9EIgEU448g+7FfDgQwcEny1pbEzAmiw zAXIQ9H0NZh96lcq+yDLtONnXk/bEYWHHUA014A1wqcYNRY8RvY1+eVHb0uu0KYQoXkzvu+s Dncuguk470XPnscL27hs8PgOP6QjG4jt75K2LfZ0eAqTOUCZTJxA8A7E9+XTYuU0hs7QVrWJ jQdFxQbRMrYz7uP8KmTK9/Cnvqehgl4EzyRaZppshruKMeyheBgvgJd5On1wWq4ZUV5PFM4x II3QbD3EJfWbaJMR55jI9dMFa+vK7MFz3rhWOkEx/QR959lfdRSTXdxs8V3zDvChcmRVGN8U Vo93d1YNtWnA9w6oCW1dnDZ4kgQZZSBIjp6iHcA08apzh7DPi08jL7M9UQByeYGr8KuR4i6e RZI6xhlZerUScVzn35ONwOC91VdYiQgjemiVLq1WDDZ3B7DIzUZ4RQTOaIWdtXBWb8zWakt/ ztGhsx0e39Gvt3391O1PgcA7ilhvqrBPemJrlb9xSPPRbaNAW39P8ws/UJnzSJqnHMVxbRZC Am4add/SM+OCP0w3xYss1jy9T+XdZa0lhUvJfLy7tNcjVG/sxkBXOaSC24MFPuwnoC9WvCVQ ZBxouph3kqc4Dt5X1EeXVLeba+466P1fe1rC8MbcwDkoUo65Ag0EVcufkQEQAOfX3n0g0fZz Bgm/S2zF/kxQKCEKP8ID+Vz8sy2GpDvveBq4H2Y34XWsT1zLJdvqPI4af4ZSMxuerWjXbVWb T6d4odQIG0fKx4F8NccDqbgHeZRNajXeeJ3R7gAzvWvQNLz4piHrO/B4tf8svmRBL0ZB5P5A 2uhdwLU3NZuK22zpNn4is87BPWF8HhY0L5fafgDMOqnf4guJVJPYNPhUFzXUbPqOKOkL8ojk CXxkOFHAbjstSK5Ca3fKquY3rdX3DNo+EL7FvAiw1mUtS+5GeYE+RMnDCsVFm/C7kY8c2d0G NWkB9pJM5+mnIoFNxy7YBcldYATVeOHoY4LyaUWNnAvFYWp08dHWfZo9WCiJMuTfgtH9tc75 7QanMVdPt6fDK8UUXIBLQ2TWr/sQKE9xtFuEmoQGlE1l6bGaDnnMLcYu+Asp3kDT0w4zYGsx 5r6XQVRH4+5N6eHZiaeYtFOujp5n+pjBaQK7wUUjDilPQ5QMzIuCL4YjVoylWiBNknvQWBXS lQCWmavOT9sttGQXdPCC5ynI+1ymZC1ORZKANLnRAb0NH/UCzcsstw2TAkFnMEbo9Zu9w7Kv AxBQXWeXhJI9XQssfrf4Gusdqx8nPEpfOqCtbbwJMATbHyqLt7/oz/5deGuwxgb65pWIzufa N7eop7uh+6bezi+rugUI+w6DABEBAAGJAiUEGAECAA8FAlXLn5ECGwwFCQlmAYAACgkQTd4Q 9wD/g1qA6w/+M+ggFv+JdVsz5+ZIc6MSyGUozASX+bmIuPeIecc9UsFRatc91LuJCKMkD9Uv GOcWSeFpLrSGRQ1Z7EMzFVU//qVs6uzhsNk0RYMyS0B6oloW3FpyQ+zOVylFWQCzoyyf227y GW8HnXunJSC+4PtlL2AY4yZjAVAPLK2l6mhgClVXTQ/S7cBoTQKP+jvVJOoYkpnFxWE9pn4t H5QIFk7Ip8TKr5k3fXVWk4lnUi9MTF/5L/mWqdyIO1s7cjharQCstfWCzWrVeVctpVoDfJWp 4LwTuQ5yEM2KcPeElLg5fR7WB2zH97oI6/Ko2DlovmfQqXh9xWozQt0iGy5tWzh6I0JrlcxJ ileZWLccC4XKD1037Hy2FLAjzfoWgwBLA6ULu0exOOdIa58H4PsXtkFPrUF980EEibUp0zFz GotRVekFAceUaRvAj7dh76cToeZkfsjAvBVb4COXuhgX6N4pofgNkW2AtgYu1nUsPAo+NftU CxrhjHtLn4QEBpkbErnXQyMjHpIatlYGutVMS91XTQXYydCh5crMPs7hYVsvnmGHIaB9ZMfB njnuI31KBiLUks+paRkHQlFcgS2N3gkRBzH7xSZ+t7Re3jvXdXEzKBbQ+dC3lpJB0wPnyMcX FOTT3aZT7IgePkt5iC/BKBk3hqKteTnJFeVIT7EC+a6YUFg= Organization: Red Hat GmbH Message-ID: Date: Mon, 2 Mar 2020 15:17:38 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.5.0 MIME-Version: 1.0 In-Reply-To: <20200302140519.GN4380@dhcp22.suse.cz> Content-Type: text/plain; charset=windows-1252 Content-Language: en-US X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 Content-Transfer-Encoding: quoted-printable Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 02.03.20 15:05, Michal Hocko wrote: > On Mon 02-03-20 14:49:34, David Hildenbrand wrote: >> A virtio-mem device wants to allocate memory from the memory region it >> manages in order to unplug it in the hypervisor - similar to >> a balloon driver. Also, it might want to plug previously unplugged >> (allocated) memory and give it back to Linux. alloc_contig_range() / >> free_contig_range() seem to be the perfect interface for this task. >> >> In contrast to existing balloon devices, a virtio-mem device operates >> on bigger chunks (e.g., 4MB) and only on physical memory it manages. I= t >> tracks which chunks (subblocks) are still plugged, so it can go ahead >> and try to alloc_contig_range()+unplug them on unplug request, or >> plug+free_contig_range() unplugged chunks on plug requests. >> >> A virtio-mem device will use alloc_contig_range() / free_contig_range(= ) >> only on ranges that belong to the same node/zone in at least >> MAX(MAX_ORDER - 1, pageblock_order) order granularity - e.g., 4MB on >> x86-64. The virtio-mem device added that memory, so the memory >> exists and does not contain any holes. virtio-mem will only try to all= ocate >> on ZONE_NORMAL, never on ZONE_MOVABLE, just like when allocating >> gigantic pages (we don't put unmovable data into the movable zone). >=20 > Same feedback as in pxm_to_node export. No objections to exporting the > symbol but it would be better to squash this function into the patch > which uses it. The changelog is highly virtio-mem specific anyway. > Maybe it is just a dejavu but I feel I have already said that but I do > not remember any details. As I said back then, I am not a friend of squashing core changes into driver changes (and AFAIK separating such is the common practice - well I have never written a driver myself). I doubt it will make review easier or faster (especially when it comes to patch #1). I can squash #4 into #5, #6 into #7, #8 into #9 if it makes your review easier. --=20 Thanks, David / dhildenb From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: virtio-dev-return-6866-cohuck=redhat.com@lists.oasis-open.org Sender: List-Post: List-Help: List-Unsubscribe: List-Subscribe: Received: from lists.oasis-open.org (oasis-open.org [10.110.1.242]) by lists.oasis-open.org (Postfix) with ESMTP id A608E985CDE for ; Mon, 2 Mar 2020 14:17:53 +0000 (UTC) References: <20200302134941.315212-1-david@redhat.com> <20200302134941.315212-5-david@redhat.com> <20200302140519.GN4380@dhcp22.suse.cz> From: David Hildenbrand Message-ID: Date: Mon, 2 Mar 2020 15:17:38 +0100 MIME-Version: 1.0 In-Reply-To: <20200302140519.GN4380@dhcp22.suse.cz> Content-Language: en-US Subject: [virtio-dev] Re: [PATCH v1 04/11] mm: Export alloc_contig_range() / free_contig_range() Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: quoted-printable To: Michal Hocko Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, virtio-dev@lists.oasis-open.org, virtualization@lists.linux-foundation.org, kvm@vger.kernel.org, Andrew Morton , "Michael S . Tsirkin" , Vlastimil Babka , Oscar Salvador , Mel Gorman , Mike Rapoport , Dan Williams , Alexander Duyck , Pavel Tatashin , Alexander Potapenko List-ID: On 02.03.20 15:05, Michal Hocko wrote: > On Mon 02-03-20 14:49:34, David Hildenbrand wrote: >> A virtio-mem device wants to allocate memory from the memory region it >> manages in order to unplug it in the hypervisor - similar to >> a balloon driver. Also, it might want to plug previously unplugged >> (allocated) memory and give it back to Linux. alloc_contig_range() / >> free_contig_range() seem to be the perfect interface for this task. >> >> In contrast to existing balloon devices, a virtio-mem device operates >> on bigger chunks (e.g., 4MB) and only on physical memory it manages. It >> tracks which chunks (subblocks) are still plugged, so it can go ahead >> and try to alloc_contig_range()+unplug them on unplug request, or >> plug+free_contig_range() unplugged chunks on plug requests. >> >> A virtio-mem device will use alloc_contig_range() / free_contig_range() >> only on ranges that belong to the same node/zone in at least >> MAX(MAX_ORDER - 1, pageblock_order) order granularity - e.g., 4MB on >> x86-64. The virtio-mem device added that memory, so the memory >> exists and does not contain any holes. virtio-mem will only try to alloc= ate >> on ZONE_NORMAL, never on ZONE_MOVABLE, just like when allocating >> gigantic pages (we don't put unmovable data into the movable zone). >=20 > Same feedback as in pxm_to_node export. No objections to exporting the > symbol but it would be better to squash this function into the patch > which uses it. The changelog is highly virtio-mem specific anyway. > Maybe it is just a dejavu but I feel I have already said that but I do > not remember any details. As I said back then, I am not a friend of squashing core changes into driver changes (and AFAIK separating such is the common practice - well I have never written a driver myself). I doubt it will make review easier or faster (especially when it comes to patch #1). I can squash #4 into #5, #6 into #7, #8 into #9 if it makes your review easier. --=20 Thanks, David / dhildenb --------------------------------------------------------------------- To unsubscribe, e-mail: virtio-dev-unsubscribe@lists.oasis-open.org For additional commands, e-mail: virtio-dev-help@lists.oasis-open.org