From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 B25953E867A for ; Mon, 12 Oct 2026 10:17:40 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1791800270; cv=none; b=ld9It6KmoBDG30UzAntS39Owwni8/Nkg2aA3R3o/klCZOCE/TuZG0hFCWGlIqTxRCr9SIKw8hDJcXkENv2rT541YQlEcro5lE9MoTB69vT9sIyauGNscxUoLu06hQQuUS5DEneMzIn0k5CnSHKJZ5ko0ykdZ8k0+kp/UmXXAV6Q= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1791800270; c=relaxed/simple; bh=Wjt9xafsmJwRLm+t7Koub+gEcsrwTZctZnayflAgvz0=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=rL3GSJtMQhp6Ua2BXK4vD7r6a5vNsaBPrSKrBJxD1bjJr7bFoJRVCIWHm5c7drgRI+9fV3AUojmaiSoQsICZ2J09usnsUhGidaru34SxzyR7TMDpqYdWnUlNy/QZQyphPpDspwmLpV2JRoCU13skd5LIPMiEQBXJM0K0NYHezS8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=boUbEq7Q; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="boUbEq7Q" Received: by smtp.kernel.org (Postfix) with ESMTPSA id B31D61F0089B; Mon, 12 Oct 2026 10:17:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1791800260; bh=6W9w6FX63BCRNL5Y5+uTi7NjbH9MTl+NIN066JxPdjM=; h=Date:From:To:Cc:Subject:References:In-Reply-To; b=boUbEq7QOkVayeZfV5djEa96a53ltXgA5Gs1RkcU/5Esvv4rZ+tT4ZLkwaSg+Olme IHJvM2BbrwxBdLd52wt/QcFMqlrTRnBPv3hPGbsA6yPQ8oyF3dxacn7kgdWIgO2tpO BK+8/qI4695zI5FCbwoeLJb3kE0o/NfshFONNz4j1LZrEHjTPM41qVFHeiKI1Dl8bF 54wXh5md4VEX0iGTFcXt6lwuqHjgRKyKjxv+NANIRvSthmS+Xe7I09U8kHdPIFi+h4 uZBGJ+ttbbK9PAK5HfWkZT+aDIXLVs1KEwXzXiP5AiFeOCj3H7ccsMXnDXybffFbpf tMhCOTQeTUF6g== Received: from phl-compute-05.internal (phl-compute-05.internal [10.202.2.45]) by mailfauth.ams.internal (Postfix) with ESMTP id 06FE7198003A; Mon, 12 Oct 2026 06:17:35 -0400 (EDT) Received: from phl-frontend-04 ([10.202.2.163]) by phl-compute-05.internal (MEProxy); Mon, 12 Oct 2026 06:17:38 -0400 X-ME-Sender: X-ME-Received: X-ME-Proxy-Cause: dmFkZTFtEePNEwvbObMFMgRHgPi1bvtoSd5qbrO694Kd+ogzCGFJMi0UGAD/xTvnHA50RE JCM/aLjoQB6DzJtDHwghLRXFYdBkvVdisA5BKYNM51m7QOeq/Kv2boQh/coCxEOLtiw8Io z3hAUsc1EkJsbOBWpNkKoT2mH3TL+rRQN3Jd7rwwgMesNQAsnBXWR75AuZ89wlgd1pnbKq uZxx3ckpzY/HsaWhu4ZNhfvqUzr/kYBIwAn462JE4fNBxYqHAOWaxSA+cD2dyHnjPtvtx8 T5vucOnKnvh5HpjQD6xc21M7w/4HzHey4lTSRpPxrJn6fsxetQs6a2bKgHgm0ZgQoSZBWZ PxyHQ6YmVw30IQBY07qLhJH9r4FyHz6QXj/UOZq/YJHs9l+F/8lWNBt1W2dNie825IsZ2s axHRX0B07aM4zLNhwIOM0LVjTNPQr7jY3qhZFEcCe6Hn0VFxWTNJfYaMwyIvpbmKFu72NS IxuefQNcRYhgSaProoMZpaBjj3HGGqb2h/eRi+pY2+JkebFi7MMRN5PiK6PoBIA5fxh/Kg I6s/xPssIUddqdP9drO7UP2Y9GJOELwEQrXKwVVrAj3HQbx0XCIx7AiX8CStCc+hffmOLA rpq1XFKxuvTkBBHb+ytkWreawLUndqwHAr8udpIY6AGNK/yrEsibS6ildKqQ X-ME-Proxy: Feedback-ID: i10464835:Fastmail Received: by mail.messagingengine.com (Postfix) with ESMTPA; Mon, 12 Oct 2026 06:17:34 -0400 (EDT) Date: Mon, 12 Oct 2026 11:17:34 +0100 From: Kiryl Shutsemau To: Andrew Morton Cc: Vlastimil Babka , Johannes Weiner , David Hildenbrand , Harry Yoo , Usama Arif , Suren Baghdasaryan , Michal Hocko , Brendan Jackman , Zi Yan , Shakeel Butt , linux-mm@kvack.org, linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@meta.com Subject: Re: [PATCH v3] mm: page_alloc: make defrag_mode retries follow the promoted order Message-ID: References: <20261009125503.126202-1-kas@kernel.org> <20261010154923.998e04e42093ffe6c7c205ee@linux-foundation.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20261010154923.998e04e42093ffe6c7c205ee@linux-foundation.org> On Sat, Oct 10, 2026 at 03:49:23PM -0700, Andrew Morton wrote: > On Fri, 9 Oct 2026 13:55:02 +0100 "Kiryl Shutsemau (Meta)" wrote: > > > Since commit 7e8756d7ad22 ("mm: page_alloc: fix non-movable reclaim > > storm in defrag_mode"), direct reclaim and compaction for non-movable > > requests under defrag_mode run at pageblock_order, to produce the whole > > blocks that ALLOC_NOFRAGMENT needs. The retry decisions that follow > > still use the request order. An order-0 request can therefore retry > > indefinitely without ever reaching the ALLOC_NOFRAGMENT fallback: > > > > ... > > > > When a promoted request takes the fallback, reset the retry counters, > > so that the fallback attempt gets a full retry budget before the OOM > > killer is considered. A request whose reclaim was not promoted spent > > its budget on the request itself and keeps its counters, as Usama Arif > > pointed out. > > Thanks, I updated mm-unstable to this version. > > > v3: > > - reset the retry counters at the fallback only for requests whose > > reclaim was promoted; a movable request already spent its budget on > > itself (Usama Arif) > > hannes's concerns/questions at > https://lore.kernel.org/20261006081050.GA234057@cmpxchg.org weren't > fully addressed? I'll add a note and await followup. Hm. I believe they were addressed. v2 changes are based on Harry's and Johannes feedback. -- Kiryl Shutsemau / Kirill A. Shutemov