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]) by smtp.lore.kernel.org (Postfix) with ESMTP id 005A7E7717D for ; Wed, 11 Dec 2024 13:04:48 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 8D4938D0015; Wed, 11 Dec 2024 08:04:48 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 884D88D0013; Wed, 11 Dec 2024 08:04:48 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 6D7488D0015; Wed, 11 Dec 2024 08:04:48 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0011.hostedemail.com [216.40.44.11]) by kanga.kvack.org (Postfix) with ESMTP id 4B0D68D0013 for ; Wed, 11 Dec 2024 08:04:48 -0500 (EST) Received: from smtpin13.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay02.hostedemail.com (Postfix) with ESMTP id C3D59120EDC for ; Wed, 11 Dec 2024 13:04:33 +0000 (UTC) X-FDA: 82882696344.13.FE91F70 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by imf07.hostedemail.com (Postfix) with ESMTP id 109464000C for ; Wed, 11 Dec 2024 13:04:05 +0000 (UTC) Authentication-Results: imf07.hostedemail.com; dkim=pass header.d=redhat.com header.s=mimecast20190719 header.b=OV3jS42e; spf=pass (imf07.hostedemail.com: domain of david@redhat.com designates 170.10.133.124 as permitted sender) smtp.mailfrom=david@redhat.com; dmarc=pass (policy=none) header.from=redhat.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1733922253; 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=pP+oty7rblXvodud5kX45/ESThaHOT5Q634wHnRNkmM=; b=3A/ebBti5/XMORFQQNRWWCXeiEuYURo3Ej0CTaBsjFJr7OVwn38d9ftLEJN4CNgfdN/MGy nldWd1yywvRjg59AL9lki/9F0knemZDY5ox2QiRk3/rObc8Z3RU/QzYZJe0ViTJ/WCV88o 8BOTFs52HaNSaTL6cSxmixhxma89XQA= ARC-Authentication-Results: i=1; imf07.hostedemail.com; dkim=pass header.d=redhat.com header.s=mimecast20190719 header.b=OV3jS42e; spf=pass (imf07.hostedemail.com: domain of david@redhat.com designates 170.10.133.124 as permitted sender) smtp.mailfrom=david@redhat.com; dmarc=pass (policy=none) header.from=redhat.com ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1733922253; a=rsa-sha256; cv=none; b=LK5gwMwDMRjanJ44R8BLElfRpiTSZsrZhktz6cyDg5Zzzw5JadBXV2LVPYoE0MqzfpxoqK G+K/o+ljHZ3mArIct+bh21/CoZt5RiWuGrrY500EqUH8wlqSJ85Hx2SOO3+XOKLSTii6Rm 7tTG5zM+x4hSC6aMHcXXvfLQWFl39n8= DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1733922270; h=from:from: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:autocrypt:autocrypt; bh=pP+oty7rblXvodud5kX45/ESThaHOT5Q634wHnRNkmM=; b=OV3jS42exX/GkJBzxxROVQAmIzcLGhBsiVBZ0pq8JlVPgTVBLEcjOCvpDX3c11pSUo3jBg 6SHcRERJJKxnJflIeo8/B+yzFAWprOUXMFmHZptjf7PrmaGbzwWyIbd00ZPpJ0Y4HR+Rpi hH0LYPKufhI43ORxPEw/lEpruLDl56I= Received: from mail-wm1-f71.google.com (mail-wm1-f71.google.com [209.85.128.71]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-564-6T1p0Ql5N5WS-LhLyJmMpQ-1; Wed, 11 Dec 2024 08:04:29 -0500 X-MC-Unique: 6T1p0Ql5N5WS-LhLyJmMpQ-1 X-Mimecast-MFC-AGG-ID: 6T1p0Ql5N5WS-LhLyJmMpQ Received: by mail-wm1-f71.google.com with SMTP id 5b1f17b1804b1-434f5b7b4a2so30733965e9.0 for ; Wed, 11 Dec 2024 05:04:29 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1733922268; x=1734527068; h=content-transfer-encoding:in-reply-to:organization:autocrypt :content-language:references:cc:to:from:subject:user-agent :mime-version:date:message-id:x-gm-message-state:from:to:cc:subject :date:message-id:reply-to; bh=pP+oty7rblXvodud5kX45/ESThaHOT5Q634wHnRNkmM=; b=WIH8BUHTEGW1n6Mf/r+qostS2SD3ucroVuXOIl8AaAqCFBK+AlPFDdsk1cYf0Sznns tV+GljcWZUIQQ3xDTA+xKyMrV+tRFUlzuXvyPUQzbFAXM8GzETvaA9RENyo1sB+Wopuu oHTvpyfVMBcf5Okd5+o+sQAM02PUhJvE/1mT9Q3SwDNyBTV8e9ojgnKjBFRGYnCJx5dp lGRJ+BL6GN1Osm3IZ1+OgJu5lNefeReLlyIpQGQuiycqJeTUNMPQ3C/zf8TPC0jRlkuq CaRM+JPmiZYumMqMZGYPw+OTx2hB4H+FGYqB6g0KxJmj1erbv6dwTAKbKNPJECwH8cEx unGA== X-Forwarded-Encrypted: i=1; AJvYcCWNJ23RvueWQk2d1XNQRPpBV0EEz4eP0z20k7MDvtabpGa38f4o/vwbQhR7B1lJZsrfVJw6dgbdeA==@kvack.org X-Gm-Message-State: AOJu0Yzd6JO7RyMs6wyDk4OXAlXyY3D3Cl/lmKmoOmyICNSk7b8NpwaK k2/eBOaEwF2AFACbYNeN90tPpEMmZr6WtaMq1fOOYM9xTIJ7tgb4K198cv6kvRcD768mIrNcc/9 DJIQl/+ijNnD+XBSk4qvOfvwr5b0blwrFm7PuKIWh+9d4hOYe X-Gm-Gg: ASbGncsi9VBRaEU0i7zToDM9SMarIHP6GNRRr2lvr33C5mM/lnrg96TzYJKNoExAjPD hTU0ECA9nkkQ0SRjn8CmrOrCkIvyxfgzlgnbFElrgwPxeIaNWM1hFiEX548VTY8cwmPZ3Yvq7ae 237ZdXoziFQ2BDK2VMuVg2vlxNsGKeu8DSw9I+ACINz4OfAGfbvZeaXuKZB1Yb8y3W8/Q9+HsiK ydVT+FNLdSzysP5lx7niFq60acrx80cb9yIcSKZ/M3Uu5niC6bJ21JHUBsbHmNjWsC7jpWnMpkt X-Received: by 2002:a5d:64e7:0:b0:386:857:cc54 with SMTP id ffacd0b85a97d-3864ce7fe32mr2252068f8f.9.1733922268306; Wed, 11 Dec 2024 05:04:28 -0800 (PST) X-Google-Smtp-Source: AGHT+IFMAQepzT22tbw/K+RGChQqrxtSY0EaW0jiP9dtZYMLRVzWLBUSNUYzgiUc0NKi+4KJZtawpA== X-Received: by 2002:a5d:64e7:0:b0:386:857:cc54 with SMTP id ffacd0b85a97d-3864ce7fe32mr2251957f8f.9.1733922266373; Wed, 11 Dec 2024 05:04:26 -0800 (PST) Received: from [10.32.64.156] (nat-pool-muc-t.redhat.com. [149.14.88.26]) by smtp.gmail.com with ESMTPSA id ffacd0b85a97d-387824c2c9dsm1245687f8f.54.2024.12.11.05.04.23 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 11 Dec 2024 05:04:25 -0800 (PST) Message-ID: Date: Wed, 11 Dec 2024 14:04:23 +0100 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v2 1/2] mm/page_alloc: conditionally split > pageblock_order pages in free_one_page() and move_freepages_block_isolate() From: David Hildenbrand To: Johannes Weiner Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, Andrew Morton , Zi Yan , Vlastimil Babka , Yu Zhao References: <20241210102953.218122-1-david@redhat.com> <20241210102953.218122-2-david@redhat.com> <20241210211613.GC2508492@cmpxchg.org> Autocrypt: addr=david@redhat.com; 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 B3JfpUqcWwE7vUaYrHG1nw54pLUoPG6sAA7Mehl3nd4pZUALHwARAQABzSREYXZpZCBIaWxk ZW5icmFuZCA8ZGF2aWRAcmVkaGF0LmNvbT7CwZgEEwEIAEICGwMGCwkIBwMCBhUIAgkKCwQW AgMBAh4BAheAAhkBFiEEG9nKrXNcTDpGDfzKTd4Q9wD/g1oFAl8Ox4kFCRKpKXgACgkQTd4Q 9wD/g1oHcA//a6Tj7SBNjFNM1iNhWUo1lxAja0lpSodSnB2g4FCZ4R61SBR4l/psBL73xktp rDHrx4aSpwkRP6Epu6mLvhlfjmkRG4OynJ5HG1gfv7RJJfnUdUM1z5kdS8JBrOhMJS2c/gPf wv1TGRq2XdMPnfY2o0CxRqpcLkx4vBODvJGl2mQyJF/gPepdDfcT8/PY9BJ7FL6Hrq1gnAo4 3Iv9qV0JiT2wmZciNyYQhmA1V6dyTRiQ4YAc31zOo2IM+xisPzeSHgw3ONY/XhYvfZ9r7W1l pNQdc2G+o4Di9NPFHQQhDw3YTRR1opJaTlRDzxYxzU6ZnUUBghxt9cwUWTpfCktkMZiPSDGd KgQBjnweV2jw9UOTxjb4LXqDjmSNkjDdQUOU69jGMUXgihvo4zhYcMX8F5gWdRtMR7DzW/YE BgVcyxNkMIXoY1aYj6npHYiNQesQlqjU6azjbH70/SXKM5tNRplgW8TNprMDuntdvV9wNkFs 9TyM02V5aWxFfI42+aivc4KEw69SE9KXwC7FSf5wXzuTot97N9Phj/Z3+jx443jo2NR34XgF 89cct7wJMjOF7bBefo0fPPZQuIma0Zym71cP61OP/i11ahNye6HGKfxGCOcs5wW9kRQEk8P9 M/k2wt3mt/fCQnuP/mWutNPt95w9wSsUyATLmtNrwccz63XOwU0EVcufkQEQAOfX3n0g0fZz Bgm/S2zF/kxQKCEKP8ID+Vz8sy2GpDvveBq4H2Y34XWsT1zLJdvqPI4af4ZSMxuerWjXbVWb T6d4odQIG0fKx4F8NccDqbgHeZRNajXeeJ3R7gAzvWvQNLz4piHrO/B4tf8svmRBL0ZB5P5A 2uhdwLU3NZuK22zpNn4is87BPWF8HhY0L5fafgDMOqnf4guJVJPYNPhUFzXUbPqOKOkL8ojk CXxkOFHAbjstSK5Ca3fKquY3rdX3DNo+EL7FvAiw1mUtS+5GeYE+RMnDCsVFm/C7kY8c2d0G NWkB9pJM5+mnIoFNxy7YBcldYATVeOHoY4LyaUWNnAvFYWp08dHWfZo9WCiJMuTfgtH9tc75 7QanMVdPt6fDK8UUXIBLQ2TWr/sQKE9xtFuEmoQGlE1l6bGaDnnMLcYu+Asp3kDT0w4zYGsx 5r6XQVRH4+5N6eHZiaeYtFOujp5n+pjBaQK7wUUjDilPQ5QMzIuCL4YjVoylWiBNknvQWBXS lQCWmavOT9sttGQXdPCC5ynI+1ymZC1ORZKANLnRAb0NH/UCzcsstw2TAkFnMEbo9Zu9w7Kv AxBQXWeXhJI9XQssfrf4Gusdqx8nPEpfOqCtbbwJMATbHyqLt7/oz/5deGuwxgb65pWIzufa N7eop7uh+6bezi+rugUI+w6DABEBAAHCwXwEGAEIACYCGwwWIQQb2cqtc1xMOkYN/MpN3hD3 AP+DWgUCXw7HsgUJEqkpoQAKCRBN3hD3AP+DWrrpD/4qS3dyVRxDcDHIlmguXjC1Q5tZTwNB boaBTPHSy/Nksu0eY7x6HfQJ3xajVH32Ms6t1trDQmPx2iP5+7iDsb7OKAb5eOS8h+BEBDeq 3ecsQDv0fFJOA9ag5O3LLNk+3x3q7e0uo06XMaY7UHS341ozXUUI7wC7iKfoUTv03iO9El5f XpNMx/YrIMduZ2+nd9Di7o5+KIwlb2mAB9sTNHdMrXesX8eBL6T9b+MZJk+mZuPxKNVfEQMQ a5SxUEADIPQTPNvBewdeI80yeOCrN+Zzwy/Mrx9EPeu59Y5vSJOx/z6OUImD/GhX7Xvkt3kq Er5KTrJz3++B6SH9pum9PuoE/k+nntJkNMmQpR4MCBaV/J9gIOPGodDKnjdng+mXliF3Ptu6 3oxc2RCyGzTlxyMwuc2U5Q7KtUNTdDe8T0uE+9b8BLMVQDDfJjqY0VVqSUwImzTDLX9S4g/8 kC4HRcclk8hpyhY2jKGluZO0awwTIMgVEzmTyBphDg/Gx7dZU1Xf8HFuE+UZ5UDHDTnwgv7E th6RC9+WrhDNspZ9fJjKWRbveQgUFCpe1sa77LAw+XFrKmBHXp9ZVIe90RMe2tRL06BGiRZr jPrnvUsUUsjRoRNJjKKA/REq+sAnhkNPPZ/NNMjaZ5b8Tovi8C0tmxiCHaQYqj7G2rgnT0kt WNyWQQ== Organization: Red Hat In-Reply-To: X-Mimecast-Spam-Score: 0 X-Mimecast-MFC-PROC-ID: 3uRSfMwFEFnZ4jj4J7ANs19lOP9uyA-D8EEklbhonLc_1733922268 X-Mimecast-Originator: redhat.com Content-Language: en-US Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Rspamd-Queue-Id: 109464000C X-Rspamd-Server: rspam12 X-Stat-Signature: 49qorhdp88cdxrdfi6zyi4uy774e5zu4 X-Rspam-User: X-HE-Tag: 1733922245-502328 X-HE-Meta: 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 6z+nS9JK Ims89uaP62mHs44Icrh2YA1jgXG7a+ff3wYtfq0MrfrQgFncDb1FWeGz+PPyxi/3kLKPz73OIcpyxivJ5uBak8D7bjt/rlKzSagiHFgmFumZWypAu8nfirj1YS6GxF6kaZJV8AGcBdFMIaTXFka8dUA+PUI24CKWNM1F9fKom2zyqPcUhzzAOrSLKntZhTIOhL8xoaMNsvPBkBLdztrrPmsP4o4W1wzCfx2eu0fyAbuBK+11yH4qm6rsYMDs7081/pd1Enfp6NrI5yzA5psAceXpDYlhzvodvuI57yrU7eamNqRKVhQuOpHhtiNwuYH6n3GgDoZqavhiM3Nr2kiLwVWcW4diMR2UKVFWysqfpyUB4ruWwDbHkUUGqLLMj6JJgPL6OXh/GxCPpm+mE48twuu0tXZX3Vkgh9IRyHfF4/eaSRs/y/3YCa0oPS1dr4oCAt2m9W0WMhQeZDBfts5BJkNaGMO7nw/iqtBBsEzoPWu/2JEw= X-Bogosity: Ham, tests=bogofilter, spamicity=0.038309, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: >> Having a function guess the caller is a bit of an anti-pattern. The >> resulting code is hard to follow, and it's very easy to >> unintentionally burden some cases with unnecessary stuff. It's better >> to unshare paths until you don't need conditionals like this. > > > In addition to the fastpath, I think you're also punishing the >> move_freepages_block_isolate() case. We *know* we just changed the >> type of one of the buddy's blocks, and yet you're still checking the >> the range again to decide whether to split. > > Yes, that's not ideal, and it would be easy to unshare that case (call > the "split" function instead of a "maybe_split" function). > > I am not 100% sure though, if move_freepages_block_isolate() can always > decide "I really have a mixture", but that code is simply quite advanced :) I played with it, and I think we can indeed assume that move_freepages_block_isolate() will always have to split. -- Cheers, David / dhildenb