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 AAEB1C8303F for ; Wed, 2 Jul 2025 12:01:46 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 294766B00C6; Wed, 2 Jul 2025 08:01:46 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 2452D6B00C7; Wed, 2 Jul 2025 08:01:46 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 0E6906B00C8; Wed, 2 Jul 2025 08:01:46 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0012.hostedemail.com [216.40.44.12]) by kanga.kvack.org (Postfix) with ESMTP id F39236B00C6 for ; Wed, 2 Jul 2025 08:01:45 -0400 (EDT) Received: from smtpin28.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay07.hostedemail.com (Postfix) with ESMTP id 8CC1E1601CB for ; Wed, 2 Jul 2025 12:01:45 +0000 (UTC) X-FDA: 83619185370.28.99E9B72 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by imf05.hostedemail.com (Postfix) with ESMTP id A70E1100015 for ; Wed, 2 Jul 2025 12:01:42 +0000 (UTC) Authentication-Results: imf05.hostedemail.com; dkim=pass header.d=redhat.com header.s=mimecast20190719 header.b="TmDc/umt"; spf=pass (imf05.hostedemail.com: domain of david@redhat.com designates 170.10.133.124 as permitted sender) smtp.mailfrom=david@redhat.com; dmarc=pass (policy=quarantine) header.from=redhat.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1751457702; 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=hbO26a8k63GS6w5haaq5bzL3sXJUv+0ecjPsgxsM3dc=; b=c+XACC3slzj0y0IE6CmSmjg10mlwPVWgEuEVGXqHecrmqi+YZ0dvHBQ0zhPMN7JxkteJj7 Gjos7XBW6HMW849ejJf8qSNt+FLSRfSfHZCu6/WHYZ3Sia5h7knmwEar+XP9Vdwf9OWI3Y Hsb/H3DVIMKWsgk0uL1J/t/Uzq993ds= ARC-Authentication-Results: i=1; imf05.hostedemail.com; dkim=pass header.d=redhat.com header.s=mimecast20190719 header.b="TmDc/umt"; spf=pass (imf05.hostedemail.com: domain of david@redhat.com designates 170.10.133.124 as permitted sender) smtp.mailfrom=david@redhat.com; dmarc=pass (policy=quarantine) header.from=redhat.com ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1751457702; a=rsa-sha256; cv=none; b=T1CByW9AxsYY4XFwY6mzIzu/5yqBr1pgx4I4npoAjhPHTxuLpDJQDIZo51d/990w5Dzz0s VHgtYZ6GhJ4/WGqkTVRh2ZeaxkmOE5HWj+4fHriA5Pf3pCprT96c5fc1O+JrCXZBbaZJZ+ qUJwhP+w1PIMvbXpi69Ut3CYDLls0EU= DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1751457702; 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=hbO26a8k63GS6w5haaq5bzL3sXJUv+0ecjPsgxsM3dc=; b=TmDc/umt+YSY08hUJsNtfGliljlHGAEOH+4VpfyBWS1KSH80oaXc2EzWNBRVoZq6lThMg3 eocfVs+p0ysPCojwD3IYrORGrGRt/E/3SfyJWmnuqEUNselpiQxGp+aVbT8znOg8YD0242 xJ3huV2+TuaP3Tm2eRo2wx+ZQExLZf0= Received: from mail-wr1-f70.google.com (mail-wr1-f70.google.com [209.85.221.70]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-656-5qUO1ciSOtibCqDGOkH-GA-1; Wed, 02 Jul 2025 08:01:40 -0400 X-MC-Unique: 5qUO1ciSOtibCqDGOkH-GA-1 X-Mimecast-MFC-AGG-ID: 5qUO1ciSOtibCqDGOkH-GA_1751457699 Received: by mail-wr1-f70.google.com with SMTP id ffacd0b85a97d-3a3696a0d3aso2095564f8f.2 for ; Wed, 02 Jul 2025 05:01:40 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1751457699; x=1752062499; h=content-transfer-encoding:in-reply-to:organization:autocrypt :content-language:from:references:cc:to:subject:user-agent :mime-version:date:message-id:x-gm-message-state:from:to:cc:subject :date:message-id:reply-to; bh=hbO26a8k63GS6w5haaq5bzL3sXJUv+0ecjPsgxsM3dc=; b=dWfZz7XV1Oxl/nimhS5msI+Rw6tkbcU5g40gXIUjZdAwP9vh5QnbOmFESm6GSLXmfl 5lRklFzX06iMvpLDpZBikNirQGDvVbq/HtE8fNz+aom144tfn5Bxa+BJsvvES2obJ6WQ w3ZR6K2F0OJF99rzhmjUzt0NkPpsvp7lNXJ7jcyUtFj2INE40iNM9dfMteY5IwhMv+6Q MXRHE31uo6RODgLnHN2or/aFmrl0/QcKHQ0/W/dd11SzVaeDlj7wCwuQ7tUBfsbMc6Rg jpnQIMzYyVJ5KnPV58M1BEaY8iSzkx4uROaAiSS7Zo+BifHNpmeVXprZLXbSIHbIVJQl 3rXw== X-Forwarded-Encrypted: i=1; AJvYcCWgFx2ohYsRyY3sFriq4YmRstby4uhdEEhLAsCn2yk5DbnQI4aobDJ/ViUTUCyEqmu+Sx1JdqK89A==@kvack.org X-Gm-Message-State: AOJu0YzMkBtb70an5izlmze2xiqYNAFz5m7U4CMqKbqQ6PORXtvvS/4z rYO7qPwFRXguye/WGK5qk+cTba3IfW0bUk8qowBu0vzEYHPWa+pcbbO2+JfFkgYyVvLlMfUzWQO PLgmpAnn9MLZ7VvmN53LEocKvOdLzDyOs3C+C8m1rRCTUmkglyrLm X-Gm-Gg: ASbGnctOk8Yf8VKnnQVSDLanasFHjnOqNgm6R1HWXSZRbVuyOoXAAphXoKeDdeW3dpf LLaI6eW2iU+HtnHvb9BFKfaVSeWCUBr2nr6z91mvCYv34ulvTt0G+CUGRVs4gl23QqgKA65G40i 48CvCaJcAlwAhDgW/2IVxSPYAlNWbVAhtMQB4txdKhd/oQiRmD6AuPNT6jhowKujdh23cVZUFeY y2Qv7gVVAwT2iD0uxP49LXw8X3ujH1q2N0cwxkiV7Vo3qGCb9KTmdcEkGse4QF6UOhPSZbg8R1O y7uq8grRjC3zNUUqQ8Keqw/XiPJYDMsOgldaygKJQPMskIrlEHsBpKU= X-Received: by 2002:a05:6000:144d:b0:3a6:d967:380e with SMTP id ffacd0b85a97d-3b1ff24427emr2184882f8f.3.1751457699131; Wed, 02 Jul 2025 05:01:39 -0700 (PDT) X-Google-Smtp-Source: AGHT+IFOIin31+Uuq9MXmWhu9WBlm6bN7FqxwwrGmyZTVwpVwvMd+yDtoM668iOg5XT1zVyyBI6yww== X-Received: by 2002:a05:6000:144d:b0:3a6:d967:380e with SMTP id ffacd0b85a97d-3b1ff24427emr2184804f8f.3.1751457698446; Wed, 02 Jul 2025 05:01:38 -0700 (PDT) Received: from ?IPV6:2a09:80c0:192:0:5dac:bf3d:c41:c3e7? ([2a09:80c0:192:0:5dac:bf3d:c41:c3e7]) by smtp.gmail.com with ESMTPSA id 5b1f17b1804b1-45388888533sm209797225e9.21.2025.07.02.05.01.35 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 02 Jul 2025 05:01:37 -0700 (PDT) Message-ID: Date: Wed, 2 Jul 2025 14:01:33 +0200 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v1 20/29] mm: convert "movable" flag in page->mapping to a page flag To: Harry Yoo Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-doc@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, virtualization@lists.linux.dev, linux-fsdevel@vger.kernel.org, Andrew Morton , Jonathan Corbet , Madhavan Srinivasan , Michael Ellerman , Nicholas Piggin , Christophe Leroy , Jerrin Shaji George , Arnd Bergmann , Greg Kroah-Hartman , "Michael S. Tsirkin" , Jason Wang , Xuan Zhuo , =?UTF-8?Q?Eugenio_P=C3=A9rez?= , Alexander Viro , Christian Brauner , Jan Kara , Zi Yan , Matthew Brost , Joshua Hahn , Rakie Kim , Byungchul Park , Gregory Price , Ying Huang , Alistair Popple , Lorenzo Stoakes , "Liam R. Howlett" , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Michal Hocko , "Matthew Wilcox (Oracle)" , Minchan Kim , Sergey Senozhatsky , Brendan Jackman , Johannes Weiner , Jason Gunthorpe , John Hubbard , Peter Xu , Xu Xin , Chengming Zhou , Miaohe Lin , Naoya Horiguchi , Oscar Salvador , Rik van Riel , Qi Zheng , Shakeel Butt References: <20250630130011.330477-1-david@redhat.com> <20250630130011.330477-21-david@redhat.com> From: David Hildenbrand 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: i1peUN_VhVJMV807nV382LB-MSg4bu-YOE0x1l9Yutk_1751457699 X-Mimecast-Originator: redhat.com Content-Language: en-US Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Rspam-User: X-Rspamd-Server: rspam05 X-Rspamd-Queue-Id: A70E1100015 X-Stat-Signature: de3h6ahdpt1ad9rg3w8dhy8xui9jua1c X-HE-Tag: 1751457702-978957 X-HE-Meta: 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 vf27tz8c /P1yZN1vkFbTcpatfAIH2s3be0gp7lsK0nBMcNooDCES3K4hs+PXyezP+aJH6tmWnDiteBXP9LkDga6UYv5hE6MgXTcvwvbugCHHniLfn+vt8Qfq2dJvX6kr+/h/kGk3evT6MNhv7toTTVmw5SaCvBAhqvnTf7NNz+xnih/hDUN4nLpiNWmZW2vKQCSOmHicTnjIXs/tl51YQea+3BW5/wagfKdD26Kq6wTBq4L067oTQuhblKYFTzDEEL9+fJZZp6qAulmLn00x+/Ghbd/x+ivBrrAQvhpraQ0BUd/wez8f1c4iUugukZTa7g1qS4+J2q3RCH2wuwWfHLmBq+EM/Sn+aD8IULzE8wKW4w/1s7v7KecyBUNKTEHOdDBWF86doVuoUPUc9zWIxNfj5Md11S0OY969tE3SQekBJDGg7Yssm98iHAd/2XZF4HF2ju7j8JBlAbbh3UkaMu7shZl6EAkxsnNZW/xQ39qrGevVr4/NBdH9UfPgPcMJe3QMpXf47ECxXJTo2/enSrbZ5FTVI0XfKQwV6jrbAG05cDhBt3VT/uDGAEFA6HrAppGZS2DJJz5Rn X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 02.07.25 13:54, Harry Yoo wrote: > On Mon, Jun 30, 2025 at 03:00:01PM +0200, David Hildenbrand wrote: >> Instead, let's use a page flag. As the page flag can result in >> false-positives, glue it to the page types for which we >> support/implement movable_ops page migration. >> >> The flag reused by PageMovableOps() might be sued by other pages, so >> warning in case it is set in page_has_movable_ops() might result in >> false-positive warnings. >> >> Reviewed-by: Zi Yan >> Signed-off-by: David Hildenbrand >> --- > > LGTM, > Reviewed-by: Harry Yoo > > With a question: is there any reason to change the page flag > operations to use atomic bit ops? As we have the page lock in there, it's complicated. I thought about this when writing that code, and was not able to convince myself that it is safe. But that was when I was prototyping and reshuffling patches, and we would still have code that would clear the flag. Given that we only allow setting the flag, it might be okay to use the non-atomic variant as long as there can be nobody racing with us when modifying flags. Especially trying to lock the folio concurrently is the big problem. In isolate_movable_ops_page(), there is a comment about checking the flag before grabbing the page lock, so that should be handled. I'll have to check some other cases in balloon/zsmalloc code. -- Cheers, David / dhildenb