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 66C4EC43458 for ; Tue, 30 Jun 2026 01:32:19 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 4D0BA6B00D0; Mon, 29 Jun 2026 21:32:18 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 480CA6B00D1; Mon, 29 Jun 2026 21:32:18 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 3707A6B00D2; Mon, 29 Jun 2026 21:32:18 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0017.hostedemail.com [216.40.44.17]) by kanga.kvack.org (Postfix) with ESMTP id 0CDF76B00D0 for ; Mon, 29 Jun 2026 21:32:18 -0400 (EDT) Received: from smtpin21.hostedemail.com (lb01a-stub [10.200.18.249]) by unirelay07.hostedemail.com (Postfix) with ESMTP id 7D8A5166938 for ; Tue, 30 Jun 2026 01:32:17 +0000 (UTC) X-FDA: 84934853514.21.5C70858 Received: from out30-97.freemail.mail.aliyun.com (out30-97.freemail.mail.aliyun.com [115.124.30.97]) by imf05.hostedemail.com (Postfix) with ESMTP id 448E7100005 for ; Tue, 30 Jun 2026 01:32:13 +0000 (UTC) Authentication-Results: imf05.hostedemail.com; dkim=pass header.d=linux.alibaba.com header.s=default header.b=TwYQJBuw; spf=pass (imf05.hostedemail.com: domain of baolin.wang@linux.alibaba.com designates 115.124.30.97 as permitted sender) smtp.mailfrom=baolin.wang@linux.alibaba.com; dmarc=pass (policy=none) header.from=linux.alibaba.com ARC-Seal: i=1; a=rsa-sha256; d=hostedemail.com; s=arc-20220608; cv=none; t=1782783135; b=7zhnr9eKWPPpKwsBRvgOt9XxuKiM3WtejHvZa7a6s3N5aBU+ojVjA6b0vLfXIo8ghpFpce 8JWZaq7r7xAYHq2WBOCIZti1VdmERVlpQowk3pZbvT+FzrpU8Ayc0C+HHwI/DhDV3tdKLM FYke8XLzkHsM6ZOaAlgUwgdXjMam2O8= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1782783135; 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=f/S/BIvky4ogkwc9B+8A9zZA9Y76XlrdAYcVHdo+9Qk=; b=BrPTJkOPEsdTfAWBVEPk6hdEGqN8BSjh+uR+u/ombEUsUZW28TLdXNLGtkyzwEzNtTSmzC Z03u/mfgLGKA0lC6+he4jcHmAlZIA82u7hG1JtrF+ajn9ZQBAN7ELr7UZ8stq01XhLIxp3 +sHEu/INALYI1ZHDHaft7BZZ2KA5Lo0= ARC-Authentication-Results: i=1; imf05.hostedemail.com; dkim=pass header.d=linux.alibaba.com header.s=default header.b=TwYQJBuw; spf=pass (imf05.hostedemail.com: domain of baolin.wang@linux.alibaba.com designates 115.124.30.97 as permitted sender) smtp.mailfrom=baolin.wang@linux.alibaba.com; dmarc=pass (policy=none) header.from=linux.alibaba.com DKIM-Signature:v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.alibaba.com; s=default; t=1782783129; h=Message-ID:Date:MIME-Version:Subject:To:From:Content-Type; bh=f/S/BIvky4ogkwc9B+8A9zZA9Y76XlrdAYcVHdo+9Qk=; b=TwYQJBuwUzT9yJmsvyUEXqK8En2t0HggSFDl4u0tKHtR4JkR/Dat5xHTTz4y/6VjYYyX0OZiWP/4LukEzl9nu99SUBm6P870z5Fu//qto1ECPQtZ9NOH6m8V46ki4be9AkWANSVLWf938GEbbd14/x40SJJ+3A37Mc+jVYeQUXM= X-Alimail-AntiSpam:AC=PASS;BC=-1|-1;BR=01201311R151e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=maildocker-contentspam033037033178;MF=baolin.wang@linux.alibaba.com;NM=1;PH=DS;RN=18;SR=0;TI=SMTPD_---0X5z0nPo_1782783127; Received: from 30.74.144.125(mailfrom:baolin.wang@linux.alibaba.com fp:SMTPD_---0X5z0nPo_1782783127 cluster:ay36) by smtp.aliyun-inc.com; Tue, 30 Jun 2026 09:32:07 +0800 Message-ID: <4154c23d-faac-4d84-990e-a9a0aec5ed46@linux.alibaba.com> Date: Tue, 30 Jun 2026 09:32:07 +0800 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH 1/4] mm/compaction: stop recording free page order in page->private To: Zi Yan , Andrew Morton , Vlastimil Babka , Suren Baghdasaryan , Michal Hocko , Brendan Jackman , Johannes Weiner , David Hildenbrand , Lorenzo Stoakes , "Liam R. Howlett" , Nico Pache , Ryan Roberts , Dev Jain , Barry Song , Lance Yang , Mike Rapoport Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org References: <20260628-keep-subpage-private-zero-at-free-v1-0-f4ce3930d10f@nvidia.com> <20260628-keep-subpage-private-zero-at-free-v1-1-f4ce3930d10f@nvidia.com> From: Baolin Wang In-Reply-To: <20260628-keep-subpage-private-zero-at-free-v1-1-f4ce3930d10f@nvidia.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Rspam-User: X-Stat-Signature: g39xpwkm851pwnbfqc8b8ut698ydmykw X-Rspamd-Queue-Id: 448E7100005 X-Rspamd-Server: rspam06 X-HE-Tag: 1782783133-562740 X-HE-Meta: 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 ThV+BAmH 3Gjk8TjZDICC05bxTNwXSzk6f+ULbr2FK6tjPPTQxLEEidZpMWuvyJ7o24Tl5isj2AuknlrOo0IJXZ3gyQC2sJZjbcOcJoo0w3UFE2eGgYqvBle/b1HfWELgu/iea+4kzKyGOvr7B5UJR5GAhonwIYHnulo6owVK1jn6Ws4SgnI05fyk+6zBnSFdVoPDM4xhdm6eMCu6pb2Ty0Ye9yAgUDUBM9xQ7y6LN4J0P/BJL4sawWSPvtfaeGNJDBshexrdefB/Cn1SOdLFdNTz5xaAZ2+EJ0lViIUelrwT0aTVNjHk12MrGC2ry3c8Bfsv5xZH9Q2+93dZmoIpdQak3HiYCUK90oS7peBFKaCvZhgw+zIwkaBcFaw+LOTMUPaSqozqkpKoMWgbk0yfu2Jucm0jOb66HyQ== Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 6/29/26 10:56 AM, Zi Yan wrote: > Commit 733aea0b3a7bb ("mm/compaction: add support for >0 order folio > memory compaction.") stores isolated free pages in an array indexed by free > page orders, it is no longer needed to store the order in each page's > ->private field. And there is no code using the stored order. Stop doing > that. > > It also prepares for an upcoming change that ensures subpage->private is I noticed that people tend to avoid using the term "subpage" now, though I understand what you mean by it here. :) [1] https://lore.kernel.org/all/20260623125723.2503832-1-dev.jain@arm.com/ > zero at page free time and the removal of set_page_private(0) from > prep_compound_tail(). In alloc_contig_frozen_range_noprof(), > isolate_freepages_range() is used to grab free pages from buddy allocator > and it leaves the aforementioned page->private set until > either split_free_frozen_pages() or prep_new_page() is called. That > triggers the upcoming subpage->private nonzero check along once > set_page_private(0) is removed from prep_compound_tail(), which is called > via prep_new_page(). > > Signed-off-by: Zi Yan > --- LGTM. Reviewed-by: Baolin Wang