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]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 62E41F8FA79 for ; Tue, 21 Apr 2026 13:31:06 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id B5A3F6B0089; Tue, 21 Apr 2026 09:31:05 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id B0A8B6B008A; Tue, 21 Apr 2026 09:31:05 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 9D24F6B008C; Tue, 21 Apr 2026 09:31:05 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0014.hostedemail.com [216.40.44.14]) by kanga.kvack.org (Postfix) with ESMTP id 8C6A96B0089 for ; Tue, 21 Apr 2026 09:31:05 -0400 (EDT) Received: from smtpin13.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay09.hostedemail.com (Postfix) with ESMTP id 429F48D414 for ; Tue, 21 Apr 2026 13:31:05 +0000 (UTC) X-FDA: 84682648890.13.1CA4D72 Received: from sea.source.kernel.org (sea.source.kernel.org [172.234.252.31]) by imf21.hostedemail.com (Postfix) with ESMTP id 508A01C001A for ; Tue, 21 Apr 2026 13:31:03 +0000 (UTC) Authentication-Results: imf21.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=NEsAvZlc; dmarc=pass (policy=quarantine) header.from=kernel.org; spf=pass (imf21.hostedemail.com: domain of david@kernel.org designates 172.234.252.31 as permitted sender) smtp.mailfrom=david@kernel.org ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1776778263; 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:dkim-signature; bh=EiQ721oSxJL+49kCE3KBrAGEyXh+20S6aF8xBPikaGw=; b=MI4KCFdatY9SRbLiYAx7TFrlwvTb8m5+0BonzPDDJJCQrikpFEpV2dR6CPWNajT3qnlFPj /IEx2plCddmRnUz+CAshgBff6YPxdSQreHVqGY54lM2S6BPCZyI9XBq8j9ytmNppxsO9P+ GKojZBD18IaXN8vcvjB8Oyz2OF0ok6E= ARC-Authentication-Results: i=1; imf21.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=NEsAvZlc; dmarc=pass (policy=quarantine) header.from=kernel.org; spf=pass (imf21.hostedemail.com: domain of david@kernel.org designates 172.234.252.31 as permitted sender) smtp.mailfrom=david@kernel.org ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1776778263; a=rsa-sha256; cv=none; b=fABFtF0Xubk9lAaJ4kqPOsSpQStwEW73B0eX1gcQSq7rie5ufXZiZ1yRW901voh5YkdWhv 3ouNSfgCeUIa4EZcDiQ7lfj4KCgqVAksoYUsAbkADrbmJnEVnVoHxRx31Cn/P6qOLEQkXp H9QZkNhTRkJl8sLvb7nNvmehaLwkLn4= Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by sea.source.kernel.org (Postfix) with ESMTP id 48F2643BD4; Tue, 21 Apr 2026 13:31:02 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 51AADC2BCB0; Tue, 21 Apr 2026 13:30:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1776778262; bh=RAnacQScZk2HHf5w6dSElvYRXNo/zrEXc78IP1F8X0Y=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=NEsAvZlcX5SJrk4ZR0PAjMGRcCWJ8os1LWUsvz29bylZrF8QKFGl7xapm9gK4L+fC xEctGyT4KI+2ilnvqq7+6Ym5FLQv4awJ8NqeA0fcCZYK2QTGr+eP9loiXW3fxlFZUm BUrR0oaAopEywO4Pd63SLRFcJT+QKK2C8D/kccePJWwNrVVduP25y4+EkgZ1pABrW1 i3prujydQyAbHLpiT5d4Hy+zpLbtx+lIHzfODQc41nLlhtxIc4ti1TsNEAdKOwqeKx 51aZZtdWKJNY9AISWjV3C26bT2UTlukbzYoACMQ8RMZZrV51uI7eAt/+hbMD4zQ3+g 74WXBMT3hHM0g== Message-ID: <2a41dd0c-7ad8-4d34-8bab-a713e16c3b29@kernel.org> Date: Tue, 21 Apr 2026 15:30:53 +0200 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH RFC v2 17/18] mm: add free_frozen_pages_hint and put_page_hint APIs To: "Michael S. Tsirkin" Cc: linux-kernel@vger.kernel.org, Andrew Morton , Vlastimil Babka , Brendan Jackman , Michal Hocko , Suren Baghdasaryan , Jason Wang , Andrea Arcangeli , linux-mm@kvack.org, virtualization@lists.linux.dev, Lorenzo Stoakes , "Liam R. Howlett" , Mike Rapoport , Johannes Weiner , Zi Yan , Chris Li , Kairui Song , Kemeng Shi , Nhat Pham , Baoquan He , Barry Song , Axel Rasmussen , Yuanchu Xie , Wei Xu References: <5f76af6e-9818-42ea-a305-c0fc1d920dca@kernel.org> <20260421091546-mutt-send-email-mst@kernel.org> From: "David Hildenbrand (Arm)" Content-Language: en-US Autocrypt: addr=david@kernel.org; keydata= xsFNBFXLn5EBEAC+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 B3JfpUqcWwE7vUaYrHG1nw54pLUoPG6sAA7Mehl3nd4pZUALHwARAQABzS5EYXZpZCBIaWxk ZW5icmFuZCAoQ3VycmVudCkgPGRhdmlkQGtlcm5lbC5vcmc+wsGQBBMBCAA6AhsDBQkmWAik AgsJBBUKCQgCFgICHgUCF4AWIQQb2cqtc1xMOkYN/MpN3hD3AP+DWgUCaYJt/AIZAQAKCRBN 3hD3AP+DWriiD/9BLGEKG+N8L2AXhikJg6YmXom9ytRwPqDgpHpVg2xdhopoWdMRXjzOrIKD g4LSnFaKneQD0hZhoArEeamG5tyo32xoRsPwkbpIzL0OKSZ8G6mVbFGpjmyDLQCAxteXCLXz ZI0VbsuJKelYnKcXWOIndOrNRvE5eoOfTt2XfBnAapxMYY2IsV+qaUXlO63GgfIOg8RBaj7x 3NxkI3rV0SHhI4GU9K6jCvGghxeS1QX6L/XI9mfAYaIwGy5B68kF26piAVYv/QZDEVIpo3t7 /fjSpxKT8plJH6rhhR0epy8dWRHk3qT5tk2P85twasdloWtkMZ7FsCJRKWscm1BLpsDn6EQ4 jeMHECiY9kGKKi8dQpv3FRyo2QApZ49NNDbwcR0ZndK0XFo15iH708H5Qja/8TuXCwnPWAcJ DQoNIDFyaxe26Rx3ZwUkRALa3iPcVjE0//TrQ4KnFf+lMBSrS33xDDBfevW9+Dk6IISmDH1R HFq2jpkN+FX/PE8eVhV68B2DsAPZ5rUwyCKUXPTJ/irrCCmAAb5Jpv11S7hUSpqtM/6oVESC 3z/7CzrVtRODzLtNgV4r5EI+wAv/3PgJLlMwgJM90Fb3CB2IgbxhjvmB1WNdvXACVydx55V7 LPPKodSTF29rlnQAf9HLgCphuuSrrPn5VQDaYZl4N/7zc2wcWM7BTQRVy5+RARAA59fefSDR 9nMGCb9LbMX+TFAoIQo/wgP5XPyzLYakO+94GrgfZjfhdaxPXMsl2+o8jhp/hlIzG56taNdt VZtPp3ih1AgbR8rHgXw1xwOpuAd5lE1qNd54ndHuADO9a9A0vPimIes78Hi1/yy+ZEEvRkHk /kDa6F3AtTc1m4rbbOk2fiKzzsE9YXweFjQvl9p+AMw6qd/iC4lUk9g0+FQXNdRs+o4o6Qvy iOQJfGQ4UcBuOy1IrkJrd8qq5jet1fcM2j4QvsW8CLDWZS1L7kZ5gT5EycMKxUWb8LuRjxzZ 3QY1aQH2kkzn6acigU3HLtgFyV1gBNV44ehjgvJpRY2cC8VhanTx0dZ9mj1YKIky5N+C0f21 zvntBqcxV0+3p8MrxRRcgEtDZNav+xAoT3G0W4SahAaUTWXpsZoOecwtxi74CyneQNPTDjNg azHmvpdBVEfj7k3p4dmJp5i0U66Onmf6mMFpArvBRSMOKU9DlAzMi4IvhiNWjKVaIE2Se9BY FdKVAJaZq85P2y20ZBd08ILnKcj7XKZkLU5FkoA0udEBvQ0f9QLNyyy3DZMCQWcwRuj1m73D sq8DEFBdZ5eEkj1dCyx+t/ga6x2rHyc8Sl86oK1tvAkwBNsfKou3v+jP/l14a7DGBvrmlYjO 59o3t6inu6H7pt7OL6u6BQj7DoMAEQEAAcLBfAQYAQgAJgIbDBYhBBvZyq1zXEw6Rg38yk3e EPcA/4NaBQJonNqrBQkmWAihAAoJEE3eEPcA/4NaKtMQALAJ8PzprBEXbXcEXwDKQu+P/vts IfUb1UNMfMV76BicGa5NCZnJNQASDP/+bFg6O3gx5NbhHHPeaWz/VxlOmYHokHodOvtL0WCC 8A5PEP8tOk6029Z+J+xUcMrJClNVFpzVvOpb1lCbhjwAV465Hy+NUSbbUiRxdzNQtLtgZzOV Zw7jxUCs4UUZLQTCuBpFgb15bBxYZ/BL9MbzxPxvfUQIPbnzQMcqtpUs21CMK2PdfCh5c4gS sDci6D5/ZIBw94UQWmGpM/O1ilGXde2ZzzGYl64glmccD8e87OnEgKnH3FbnJnT4iJchtSvx yJNi1+t0+qDti4m88+/9IuPqCKb6Stl+s2dnLtJNrjXBGJtsQG/sRpqsJz5x1/2nPJSRMsx9 5YfqbdrJSOFXDzZ8/r82HgQEtUvlSXNaXCa95ez0UkOG7+bDm2b3s0XahBQeLVCH0mw3RAQg r7xDAYKIrAwfHHmMTnBQDPJwVqxJjVNr7yBic4yfzVWGCGNE4DnOW0vcIeoyhy9vnIa3w1uZ 3iyY2Nsd7JxfKu1PRhCGwXzRw5TlfEsoRI7V9A8isUCoqE2Dzh3FvYHVeX4Us+bRL/oqareJ CIFqgYMyvHj7Q06kTKmauOe4Nf0l0qEkIuIzfoLJ3qr5UyXc2hLtWyT9Ir+lYlX9efqh7mOY qIws/H2t In-Reply-To: <20260421091546-mutt-send-email-mst@kernel.org> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Rspam-User: X-Rspamd-Server: rspam01 X-Rspamd-Queue-Id: 508A01C001A X-Stat-Signature: 8cfqrx4qgmp9fje59gxysnbc9zdz4bw7 X-HE-Tag: 1776778263-16042 X-HE-Meta: U2FsdGVkX19r74DXcRw2cKs1cyc2yakuO0X8YwKuIhD9yDNchezNxhU4SresqHSl/cffN1JcxKnSFmtNADpx6X4dgJVFmx7OPcYXSV0845PniptlqX/V1EFetj8nvk8JFNrKXgdfqC5dN3yi4xL2HInVZ09boOMAoKN2W5A42FBRvUsNB1UDGe5D+1Y6AqfgvRP30k0bHT/KYlcLGz4NKXHSudRi0wd/ms4DKTMR334+IVicp88ZJnYcu8IADYHwjtlxKSazQMDxn7D3FwWRkHvA4PTPhZ0ixRBbGg5FVtl8Hv34y/Duwh0Qnyaofv9lS/qh9IAuj1ixVRO/uSnFigvPHMcJCg9Ihy7SLuD8Un4HBX+e7n8Mo1KYiUurE7p0CJKVLnhtDMTQWI5QBtuY+SavJofO47pbPziI3lQ2pmRmilYKIkijtUn32h42LCPeu9fdcyYEsjdnxoo4KgdX6fXqXJpSikSb7fEq7/nxvMH09NGiZEzPymaswkKWrVLVWmep209Oy0t5AlHYDfvN861SPdMw78MA9xeXaryIf5VWPyI6qLeAvrsdWJUw/aSyrFE6ICSml3WyXpCvDmBFMIPi7jQC+isY1rVnUv35xwFRUIMrU5cR2vNMsfSglrw5Lb0bJWB52XUK4u2i70eswxBkLSxji9DnBJ8SHVfof+G8LZku3j/E2ovD4X90xxXREm1jmT+m1qc5O/wRxZj9zjiK06aTcUprT119dBlaV9B8IOjxjb9iadPsvgx9NLTXqRVMzuul++MH/EONTd+yRsn4m++N4M0TI1/EoIjvPfWg2ihBZp2WvSZAb0rYBTtEz27xZ8jqfFXNInarY+MuKUehnUe99omk8wyEGVzapKbz9KZJQMFIEhQEQQcQcFEJ170vZUZtHqMBfAvYdlwFdh5WAvTzisZrzSFa0zfGL1C0AoTiec4Bk+dCGaJOJZ7oagi+VM4zVZufQs9HdyS 8VtD3zzE lwLMq1t+9sw5nd555n+jL/0Rm8ZZjBG66N7HyoF4WxqiRStY+W+qTMAS6sD6KskeZk5BWgg5aaw/scbu3SHqRYKM2kEpNdtFx0Y0MX9vjDK+6E0rqwRVfC6dzNH0IOHWsKmC71+tBUXfAc87qd/rx9GKP6squFxUz7BX9nd16KD7ezG726enmlE8bCL2EdOZ15LU7+GB7y7XT/K9OcNYtPomBLlqTssZjlyF1rb1HASaek1AuzgfuBZ8sH3HSay/K4b+nbhMbOcugjCjh56dA7ylMyz28WQ+x/phxWd2PXdlgge1Z/UxlW1drYg== Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 4/21/26 15:16, Michael S. Tsirkin wrote: > On Tue, Apr 21, 2026 at 12:56:00PM +0200, David Hildenbrand (Arm) wrote: >> On 4/20/26 14:51, Michael S. Tsirkin wrote: >>> Add free_frozen_pages_hint(page, order, hints) to free a page >>> while marking it as pre-zeroed when PGHINT_ZEROED is set. >>> The PG_zeroed flag is set after __free_pages_prepare so it >>> survives on the free list. >>> >>> Add __folio_put_hint(), folio_put_hint(), and put_page_hint() >>> wrappers for the put_page path. >> >> Can we defer that change? > > We can - it's a dependency of the balloon deflate, which you asked > me to implement. I'm more interested in reporting, myself. Just to be clear, I said: "I'd assume ordinary inflating+deflating of the balloon would also end up with pre-zeroed pages. We'd just need a (mm/balloon.c -specific) interface to tell the buddy that the pages are zeroed." So while I think there will be value in that in the futur once we figure out a clean interface, I don't recall asking you to implement that? -- Cheers, David