From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from invmail4.hynix.com (exvmail4.hynix.com [166.125.252.92]) by smtp.subspace.kernel.org (Postfix) with ESMTP id C252D30E856; Mon, 3 Nov 2025 12:39:49 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=166.125.252.92 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1762173596; cv=none; b=KycNY/takeSRYqIxmF7ujkW3qTGgsgTpH7eriYjnziVoT2w09pTD5a85HckBFwU9+HaqrmWuzKYv+SDkt6qUpeEuaW37ynkzeleR1+qm3lqV49+MXs/EuN9rjQ5tvP6PnOpsWy2ZSE1xHP/OS+O7Mc6AX/luLYz5X/0BGQayXCk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1762173596; c=relaxed/simple; bh=NahZnGHbeWb05O39co6q17AfcLe2V4xIORGRnSkMmng=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=RWSl7DoTCAVl50Rs5TRBOi21lhb8w6KR8/7sNUdWd4kfUvHK/i6JU6oyjyGbaVwhWJr8lAYEWZyqF33h9G4cefSI0Z5Xla9seJA/upGPaeh1QkLAnH0iXJVB+RChxqxJGNNgoup7e4rtYUzEVXLnGWOLjSL8Sxe961qZ+glGB3A= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=sk.com; spf=pass smtp.mailfrom=sk.com; arc=none smtp.client-ip=166.125.252.92 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=sk.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=sk.com X-AuditID: a67dfc5b-c2dff70000001609-34-6908a293b816 Date: Mon, 3 Nov 2025 21:39:42 +0900 From: Byungchul Park To: Toke =?iso-8859-1?Q?H=F8iland-J=F8rgensen?= Cc: linux-mm@kvack.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, kernel_team@skhynix.com, harry.yoo@oracle.com, ast@kernel.org, daniel@iogearbox.net, davem@davemloft.net, kuba@kernel.org, hawk@kernel.org, john.fastabend@gmail.com, sdf@fomichev.me, saeedm@nvidia.com, leon@kernel.org, tariqt@nvidia.com, mbloch@nvidia.com, andrew+netdev@lunn.ch, edumazet@google.com, pabeni@redhat.com, akpm@linux-foundation.org, david@redhat.com, lorenzo.stoakes@oracle.com, Liam.Howlett@oracle.com, vbabka@suse.cz, rppt@kernel.org, surenb@google.com, mhocko@suse.com, horms@kernel.org, jackmanb@google.com, hannes@cmpxchg.org, ziy@nvidia.com, ilias.apalodimas@linaro.org, willy@infradead.org, brauner@kernel.org, kas@kernel.org, yuzhao@google.com, usamaarif642@gmail.com, baolin.wang@linux.alibaba.com, almasrymina@google.com, asml.silence@gmail.com, bpf@vger.kernel.org, linux-rdma@vger.kernel.org, sfr@canb.auug.org.au, dw@davidwei.uk, ap420073@gmail.com, dtatulea@nvidia.com Subject: Re: [RFC mm v5 2/2] mm: introduce a new page type for page pool in page type Message-ID: <20251103123942.GA64460@system.software.com> References: <20251103075108.26437-1-byungchul@sk.com> <20251103075108.26437-3-byungchul@sk.com> <87jz07pajq.fsf@toke.dk> Precedence: bulk X-Mailing-List: linux-rdma@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <87jz07pajq.fsf@toke.dk> User-Agent: Mutt/1.9.4 (2018-02-28) X-Brightmail-Tracker: H4sIAAAAAAAAA02SWUwTYRSF889MZ6YNjUNF+BETTV3jAm6J17ihUfMb18QHN6I2MtLGAqYo glGDiFsVXJBIC8aqEShCwCq0JWKUHdwIbjXK6oJBrMhSqahIUSNvJ+eee777cHla0SIZyWsi 9oi6CJVWycoY2WevK9OSr/Ka6dn1AOl5OSzc6I2BzCabBNw5rRSkZxci6Ha/5qC/uAJBV1kl C59KOxFcu+KiIf1JAgM9ed9psBe1ImhLzWXhfUULBzcsq6Ex4wMDd45baWg5U8VCYkIfDcVu JwfxtqyB4ltxHNQWJkngwvfrNFjjmjh4WpTOQkNOvwQ+lCQyUG00M9CRUkZDY1IwVJh8wfWg HUFZnpUC1+lLLDw3FFFQUPycg+Q6EwtvExoR1JW2MJDy4wQLaYeTEPT1DlQ6z3ZLIK28gQsO JIcdDpaUtn+hyW3zK4q8SD3HEMfdGorYjfUcMVn2kltZk4neUUcTS/ZJllg6z3PkzYs7LKlK 7WOIvXkusdu6KJJ4xMmuG7FZNj9U1GqiRV3Qwu0ydZU1hdr9zSum9ls5E4ceyvRIymNhNnYd raD+6fziR4xHM8I4XJ/slng0K0zEDoeb1iOe9xEW4we9YXok42nByeH+3FbakxkubMBfHA2D ebkA2PrSPOgrhAO4sib5r++Nqw3vBvtpYSq2F7xhPZ20EIAzf/F/7NH4SEHa4KpUGI8NJz8i jx4hjMX3CispDxcLp6S4tLof/bnZH9/PcjBnkbdxCMI4BGH8jzAOQZgQk40UmojocJVGOztQ HRuhiQncERluQQOfl3HwxxYb6qxdX4IEHim95MTEaxQSVXRUbHgJwjyt9JHrYwcseagqdr+o i9ym26sVo0pQAM8o/eQzXftCFUKYao+4SxR3i7p/U4qXjoxDqcPjQfGoZ9W7sDX2Cf7SkHy/ jWE7V+Z68eruoI9PfZucSm/X8qZ7ywzP2uMv7njML22OH2OZsmBYUChp65nVnZ9wLPhyuXvt z3kHTDcNZ6Y0H1tBxr6SjcpcpN3I+EWqAzLaQoT9VujYfKhvyaY5XZO2mv3R15fRD9dytnPl HZfMSiZKrZoxmdZFqX4DHLABhHUDAAA= X-Brightmail-Tracker: H4sIAAAAAAAAA03SbUxTZxQH8Dz3eXrvpVp3ZahXCdHVt4woSjLMmRqjwcQnJho/LBr9InXe 0AYoplVCF02qEJ2NrSI2QqlaNQMpNZAilHZ0cYC86BYZBFdUwDEtBpQaxUoBRYoa+fbP/5zz +3R4HNskW8RrtIclnVaVqWTlRL5zQ97qwmu8Zm2o+juwV7pYqBjNhbIndTKIuAYYsDtrEYxE HnEw6W9G8KaphYWhxtcIrl8NY7DfzyfwtnIMg9c3gGCw6CYLz5r7Oahw74C+0iCB+lMeDP1n W1kw549j8EeGOThRd2MKrjZy0HipTQbttRYZXBj7DYPH+ISDTp+dhV7XpAyCDWYCbbZyAq+s TRj6LJuh2TEfwvdeIGiq9DAQPnOJha5iHwM1/i4OCjscLPyf34ego7GfgHXiVxZKjlsQjI9O kcPnRmRQcqeX27yGHg8EWNr4IoTprfJuhj4oKiA08MddhnptPRx1uI/Q6huJ1BTowNTtPM1S 9+vzHH38oJ6lrUXjhHr/+5F6694w1Jw3zO6av0++8aCUqcmRdGs2pcnVrR4rc+jd7Nz2d3eI Ef0lN6EYXhR+EKv8f5NoJsIysacwIotmVlgpBgIRbEI8HydsEe+NppuQnMfCMCdO3hzA0Z1v hT1iKNA7va8QQPT8Wz7dxwpHxZa7hZ/7uWJb8dNpHwurRG/NYzZqYiFeLPvAf6oXi3k1JdOn McJysfj0cxTN84Sl4u3aFuYcmmObIdlmSLavkm2G5EDEieI02pwslSYzJUmfoTZoNblJP2dn udHUb5UemyioQyOd2xqQwCPlbAV18JpYmSpHb8hqQCKPlXEKk2GqUhxUGX6RdNn7dUcyJX0D iueJcoFi+x4pLVZIVx2WMiTpkKT7MmX4mEVGlFyG1+/NGNiuujbIXCcPLXbmxIr3Pun7Hlib fLFr1jfGKlKfcGVw6M9S24RBedSdVKH90Hbx/SnfyytVJ0vMY/7E+suzxteHljjM/2wLLnT5 f3rqSt/6Momk7A6tWubcZbds3RhUr1waVIc749bdTrP+viI1q5saH6U4w6kJ1gNKolerkhOx Tq/6CMKBWTFXAwAA X-CFilter-Loop: Reflected On Mon, Nov 03, 2025 at 01:26:01PM +0100, Toke Høiland-Jørgensen wrote: > Byungchul Park writes: > > > Currently, the condition 'page->pp_magic == PP_SIGNATURE' is used to > > determine if a page belongs to a page pool. However, with the planned > > removal of ->pp_magic, we should instead leverage the page_type in > > struct page, such as PGTY_netpp, for this purpose. > > > > Introduce and use the page type APIs e.g. PageNetpp(), __SetPageNetpp(), > > and __ClearPageNetpp() instead, and remove the existing APIs accessing > > ->pp_magic e.g. page_pool_page_is_pp(), netmem_or_pp_magic(), and > > netmem_clear_pp_magic(). > > > > This work was inspired by the following link: > > > > [1] https://lore.kernel.org/all/582f41c0-2742-4400-9c81-0d46bf4e8314@gmail.com/ > > > > While at it, move the sanity check for page pool to on free. > > > > Suggested-by: David Hildenbrand > > Co-developed-by: Pavel Begunkov > > Signed-off-by: Pavel Begunkov > > Signed-off-by: Byungchul Park > > Acked-by: David Hildenbrand > > Acked-by: Zi Yan > > Acked-by: Mina Almasry > > Acked-by: Toke Høiland-Jørgensen > > IIUC, this will allow us to move the PP-specific fields out of struct > page entirely at some point, right? What are the steps needed to get to > that point after this? Yes, it'd be almost done once this set gets merged :-) Will check if I can safely remove pp fields from struct page, and do it! Byungchul > > -Toke