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 21837EB64DA for ; Thu, 20 Jul 2023 05:38:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229653AbjGTFiC (ORCPT ); Thu, 20 Jul 2023 01:38:02 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42904 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229561AbjGTFiB (ORCPT ); Thu, 20 Jul 2023 01:38:01 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E2CF31726 for ; Wed, 19 Jul 2023 22:38:00 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 793AF61803 for ; Thu, 20 Jul 2023 05:38:00 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 9EC4CC433C8; Thu, 20 Jul 2023 05:37:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1689831479; bh=a4gK1D97qFOeqsvBd2dHAlBTxcjDDuDOYGdbrbAW3bg=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=I5vaqIQNSWRtNNeV0sxBPgE6Nu23tFiqCWrelX/PN3qtlgs7brOuJPbOPLbRpg6L4 aaU0eF0YcHxLe0LdaU/Bbc2qECE3LLOf/b4s2rTDpoTX63hjrM51DrD98nj17ES2FQ MWe9XaWwkqWmiiokl5CPdiTIOVFKF4yyaqUbCjqw9iOUZEevTMc0ooZrj+a4GDFct+ yexyxWdKjtCTYOLwI3WG3MvoKKmkYymqbL+tjkqgMbh1TEh9MQKqxIf7eFCgBwXxQD HzEYRLUe5T5TezlqlmW/ULE7+hRDYsYovGkAuvFyrfQ0GdW/lSuG59J3zrQ9o7+hYN MgyxXV8w3fW4Q== Date: Thu, 20 Jul 2023 08:37:36 +0300 From: Mike Rapoport To: Kemeng Shi Cc: akpm@linux-foundation.org, pasha.tatashin@soleen.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 0/3] add page_ext_data to get client data in page_ext Message-ID: <20230720053736.GM1901145@kernel.org> References: <20230718145812.1991717-1-shikemeng@huaweicloud.com> <20230719094421.GI1901145@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, On Thu, Jul 20, 2023 at 10:38:39AM +0800, Kemeng Shi wrote: > > on 7/19/2023 5:44 PM, Mike Rapoport wrote: > > On Tue, Jul 18, 2023 at 10:58:09PM +0800, Kemeng Shi wrote: > >> Current client get data from page_ext by adding offset which is auto > >> generated in page_ext core and expose the data layout design insdie > >> page_ext core. This series adds a page_ext_data to hide offset from > >> client. Thanks! > > > > Implementers of page_ext_operations are anyway intimately related to > > page_ext, so I'm not convinced this has any value. > > > Hi Mike, thanks for reply. I thinks page_ext_operations can be futher splited > into public part which used by client to simply register and private part which > only page_ext core cares and should not be accessed by client directly > to reduce decoupling. It would be easier to justify changes in this series if they were a part of the refactoring you describe here. > This series makes offset to be private which client > doesn't really care to hide data layout inside page_ext core from client. > There are some concrete gains I can list for now: > 1. Future client cound call page_ext_data directly instead of define a > new function like get_page_owner to get it's data. > 2. No change to client if layout of page_ext data change. These should be a part of the changelog. > I hope this could be more convincing to you now. > Thanks! > > -- > Best wishes > Kemeng Shi > -- Sincerely yours, Mike.