From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id E62F31E493C; Fri, 21 Mar 2025 05:14:54 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=198.137.202.133 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1742534098; cv=none; b=Ol6B1hGJj2GDJZTzgE6hjMEJkWk2SbHqLzsuvO70xMn043S8K0tYkS0nIwbqKSbae/SuWmcaFj3E0MNnvJcMXeJGI1hRXaPuVkSbruQO0OC6rYggXpQA6AcmQnO0GeL/vkqUnMJ9jP3pb0xdNIa5+Dlzw5wjSv4V4CxyzloPw+c= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1742534098; c=relaxed/simple; bh=xdG9r9zig5930+Z9+K5PrYoRrYhQzmwyeGDldmRg6fM=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=A4IxCqx65jsDNo0m/34U/MgSROzar4pBrWfR5PaIcczYQ6VOMDYzsxpLP6y6aA/hcpfqzZuZ7Ii2W8NuEwm3ooP3jC0HhleMufXHWlLDgoze67MRv4AfPZikyose7B1BMbcZckp5EX0yjPBQUIaSEp+B8ALLqjeXfawiDL9FiQs= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org; spf=none smtp.mailfrom=bombadil.srs.infradead.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b=1wmiI9+V; arc=none smtp.client-ip=198.137.202.133 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=bombadil.srs.infradead.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="1wmiI9+V" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20210309; h=In-Reply-To:Content-Type:MIME-Version :References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=fIC/SAXuaviF4kGty41Kn3ZZ26v8zIm5FHzMRtfkfFc=; b=1wmiI9+VZjGjXVJSYgYQgrg6N1 t5dpCQ9cWL8kFMKwc19IlHoDP7CaQdDWJhrB8p7UjT/s0y+sKqjIWWZfy/VHNp3CoCXALSc7yKnbR iI3qfxX9AFYNvdMABaL+ZQ3Wq94cBUX/4ZGjDQpEEqxbCkNaBG9X47Lx3OXVA+GBnEAhNjC+DC1lS 9h4zNL/fx2G2f6uOLH+8ehqAH5Byvo0FHJOm32VV0yA8YncZ/7GRtxSoOJwwDOOogrYawcbuA9HrH c90vZ+beiRPDIl915nDJC97Vd1M1BlHuVnb/zBYhDVi4KK80b5b+/UQQCW5v/Dysa3Uuq8pCi69Sc s79lkjwA==; Received: from hch by bombadil.infradead.org with local (Exim 4.98 #2 (Red Hat Linux)) id 1tvUiR-0000000DsQw-3ibf; Fri, 21 Mar 2025 05:14:43 +0000 Date: Thu, 20 Mar 2025 22:14:43 -0700 From: Christoph Hellwig To: Suren Baghdasaryan Cc: akpm@linux-foundation.org, willy@infradead.org, david@redhat.com, vbabka@suse.cz, lorenzo.stoakes@oracle.com, liam.howlett@oracle.com, alexandru.elisei@arm.com, peterx@redhat.com, hannes@cmpxchg.org, mhocko@kernel.org, m.szyprowski@samsung.com, iamjoonsoo.kim@lge.com, mina86@mina86.com, axboe@kernel.dk, viro@zeniv.linux.org.uk, brauner@kernel.org, hch@infradead.org, jack@suse.cz, hbathini@linux.ibm.com, sourabhjain@linux.ibm.com, ritesh.list@gmail.com, aneesh.kumar@kernel.org, bhelgaas@google.com, sj@kernel.org, fvdl@google.com, ziy@nvidia.com, yuzhao@google.com, minchan@kernel.org, linux-mm@kvack.org, linuxppc-dev@lists.ozlabs.org, linux-block@vger.kernel.org, linux-fsdevel@vger.kernel.org, iommu@lists.linux.dev, linux-kernel@vger.kernel.org, Minchan Kim Subject: Re: [RFC 2/3] mm: introduce GCMA Message-ID: References: <20250320173931.1583800-1-surenb@google.com> <20250320173931.1583800-3-surenb@google.com> Precedence: bulk X-Mailing-List: iommu@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20250320173931.1583800-3-surenb@google.com> X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html On Thu, Mar 20, 2025 at 10:39:30AM -0700, Suren Baghdasaryan wrote: > From: Minchan Kim > > This patch introduces GCMA (Guaranteed Contiguous Memory Allocator) > cleacache backend which reserves some amount of memory at the boot > and then donates it to store clean file-backed pages in the cleancache. > GCMA aims to guarantee contiguous memory allocation success as well as > low and deterministic allocation latency. > > Notes: > Originally, the idea was posted by SeongJae Park and Minchan Kim [1]. > Later Minchan reworked it to be used in Android as a reference for > Android vendors to use [2]. That is not a very good summay. It needs to explain how you ensure that the pages do stay clean forever.