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 kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id E162EC28B28 for ; Wed, 12 Mar 2025 12:06:19 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id B34E2280004; Wed, 12 Mar 2025 08:06:17 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id A96CB280001; Wed, 12 Mar 2025 08:06:17 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 93B33280004; Wed, 12 Mar 2025 08:06:17 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0011.hostedemail.com [216.40.44.11]) by kanga.kvack.org (Postfix) with ESMTP id 1AECF280001 for ; Wed, 12 Mar 2025 08:06:16 -0400 (EDT) Received: from smtpin19.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay10.hostedemail.com (Postfix) with ESMTP id 4D008C1002 for ; Wed, 12 Mar 2025 12:06:17 +0000 (UTC) X-FDA: 83212771194.19.6D5ADA5 Received: from szxga04-in.huawei.com (szxga04-in.huawei.com [45.249.212.190]) by imf25.hostedemail.com (Postfix) with ESMTP id 1A12DA002B for ; Wed, 12 Mar 2025 12:06:13 +0000 (UTC) Authentication-Results: imf25.hostedemail.com; dkim=none; dmarc=pass (policy=quarantine) header.from=huawei.com; spf=pass (imf25.hostedemail.com: domain of linyunsheng@huawei.com designates 45.249.212.190 as permitted sender) smtp.mailfrom=linyunsheng@huawei.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1741781174; h=from:from:sender: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=KrOqBNCmKx+7PKcm7bqQN5WMEoXSaJfHWJFhcN5NhTA=; b=7xf//eeh86bhKtr7duSg6vKS2cMJIgG63dYAlFYIKM/8HOswfIJRSbbtLwg+MG2eknvlDP RyeJh2eJSOaeYfgfs7En7GGh82nFoCPQfOwu72jQa+0SyxPnNFwyMF31uwSsyp+4klhZMM /pvFRnb5/ZqJTKWo2rRTVk0A/0FhuYc= ARC-Authentication-Results: i=1; imf25.hostedemail.com; dkim=none; dmarc=pass (policy=quarantine) header.from=huawei.com; spf=pass (imf25.hostedemail.com: domain of linyunsheng@huawei.com designates 45.249.212.190 as permitted sender) smtp.mailfrom=linyunsheng@huawei.com ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1741781174; a=rsa-sha256; cv=none; b=VV+bP3KaMeEPTfEn357brOZ13S6RvF+Yc6kMFdWs8DOrbFGUpjEe6SAMEcbFA9VMlhXIit VgE3cdLftnt+zPUAcnEyP8dgX/xZGEK05jE8khJLhvdi2f7RAQE6KQ0VkoT4evS2EV87Zw NQ1kGomuqZAeI0xwelMq2xQvXrEhVGs= Received: from mail.maildlp.com (unknown [172.19.88.214]) by szxga04-in.huawei.com (SkyGuard) with ESMTP id 4ZCTjp20x6z2RTLH; Wed, 12 Mar 2025 20:01:02 +0800 (CST) Received: from dggpemf200006.china.huawei.com (unknown [7.185.36.61]) by mail.maildlp.com (Postfix) with ESMTPS id E62F51A016C; Wed, 12 Mar 2025 20:05:23 +0800 (CST) Received: from [10.67.120.129] (10.67.120.129) by dggpemf200006.china.huawei.com (7.185.36.61) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1544.11; Wed, 12 Mar 2025 20:05:22 +0800 Message-ID: <8fa8f430-5740-42e8-b720-618811fabb22@huawei.com> Date: Wed, 12 Mar 2025 20:05:22 +0800 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [RFC PATCH net-next] page_pool: Track DMA-mapped pages and unmap them when destroying the pool To: Matthew Wilcox CC: =?UTF-8?Q?Toke_H=C3=B8iland-J=C3=B8rgensen?= , Yunsheng Lin , Andrew Morton , Jesper Dangaard Brouer , Ilias Apalodimas , "David S. Miller" , Yonglong Liu , Mina Almasry , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Simon Horman , , , References: <20250308145500.14046-1-toke@redhat.com> <87cyepxn7n.fsf@toke.dk> Content-Language: en-US From: Yunsheng Lin In-Reply-To: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit X-Originating-IP: [10.67.120.129] X-ClientProxiedBy: dggems702-chm.china.huawei.com (10.3.19.179) To dggpemf200006.china.huawei.com (7.185.36.61) X-Rspam-User: X-Rspamd-Queue-Id: 1A12DA002B X-Rspamd-Server: rspam08 X-Stat-Signature: mp9k38n1kskjdqobkkwixehhnxazdwkz X-HE-Tag: 1741781173-197614 X-HE-Meta: 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 AyNi3cKU W1QqL8SRvgQvW35MdkftwPtiXEazz4bESWAuKnfZrkBCFTob+sn4pXCQ0Z/2SCc+zhiFZRM4+q0azArKESmeVeqsMTbspC0Zvh3QURVtMkXNPN1p3Q0YBr78RsykWMTl1sZJeW/TsEhHxm5yOe1iIJykEIfsOS3hfQHdPPMv0D6KBQLT+H949TvjwJ3e46NjYFeRxAyPQJUMbVTrVvSQ9oO1mi5OEzyhmXBmQ X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 2025/3/11 23:11, Matthew Wilcox wrote: > On Tue, Mar 11, 2025 at 08:25:25PM +0800, Yunsheng Lin wrote: >>> struct page { >>> unsigned long flags; >>> unsigned long memdesc; >> >> It seems there may be memory behind the above 'memdesc' with different size >> and layout for different subsystem? > > Yes. > >> I am not sure if I understand the case of the same page might be handle in >> two subsystems concurrently or a page is allocated in one subsystem and >> then passed to be handled in other subsystem, for examlpe: >> page_pool owned page is mmap'ed into user space through tcp zero copy, >> see tcp_zerocopy_vm_insert_batch(), it seems the same page is handled in >> both networking/page_pool and vm subsystem? > > It's not that arbitrary. I mean, you could read all the documentation > I've written about this concept, listen to the talks I've given. But > sure, you're a special fucking snowflake and deserve your own unique > explanation. If you don't like responding to the above question/comment, I would rather you strip out them like the other question/comment or just ignore it:( I am not sure how to interpret the comment, but I am sure it is not a kind one, so CC 'Code of Conduct Committee' in case there is more coming. > >