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 3BC84CA5FCB for ; Thu, 1 Oct 2026 11:41:16 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 5A47E6B0096; Thu, 1 Oct 2026 07:41:15 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 57C7B6B0098; Thu, 1 Oct 2026 07:41:15 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 492836B0099; Thu, 1 Oct 2026 07:41:15 -0400 (EDT) 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 331196B0096 for ; Thu, 1 Oct 2026 07:41:15 -0400 (EDT) Received: from smtpin02.hostedemail.com (lb01a-stub [10.200.18.249]) by unirelay05.hostedemail.com (Postfix) with ESMTP id A728D403BD for ; Thu, 1 Oct 2026 11:41:14 +0000 (UTC) X-FDA: 85273866468.02.F9EC06B Received: from tor.source.kernel.org (tor.source.kernel.org [172.105.4.254]) by imf16.hostedemail.com (Postfix) with ESMTP id E9AB3180007 for ; Thu, 1 Oct 2026 11:41:12 +0000 (UTC) Authentication-Results: imf16.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20260515 header.b=LTwFk0ZU; spf=pass (imf16.hostedemail.com: domain of david@kernel.org designates 172.105.4.254 as permitted sender) smtp.mailfrom=david@kernel.org; dmarc=pass (policy=quarantine) header.from=kernel.org ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1790854872; 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=OTQjaHyFzgR+M9iAe8/wiUOMwWAu1rzKJDK8Ma1143k=; b=rCO2N62y3vgwKz0JxYZub29PBgVvWuFEVjOqDASEXHLw6gZ7UMxDTjL7U6ds2ZlJbISPk+ 8q/+yIyDYtYYBD4qxozZJ5TE/VQ+e79sojmWr0jpuAiEP8t165gEgx6Y/pAxWzt3XoiTPq W0ZE3UZttb9v7Jwe1wOzDoVcVRXJ+5Y= ARC-Authentication-Results: i=1; imf16.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20260515 header.b=LTwFk0ZU; spf=pass (imf16.hostedemail.com: domain of david@kernel.org designates 172.105.4.254 as permitted sender) smtp.mailfrom=david@kernel.org; dmarc=pass (policy=quarantine) header.from=kernel.org ARC-Seal: i=1; a=rsa-sha256; d=hostedemail.com; s=arc-20220608; cv=none; t=1790854872; b=uCMB7bCDfWFC3fj2vS11+GKWICpHwZkPO/tMjx7muvLdUylkTmtgjtTB4XtjDVECYjMfh5 8OkZP7Nhu3NZYjgBQvpSYEtkKdIfAUXtp9SykEvkItKORQvTmSQ1SqdK5Yld64iw8ZlvEW Zdtpsxmu0bAVt7B/58bn1L2NV4VYm7w= Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) by tor.source.kernel.org (Postfix) with ESMTP id 8D869601E4; Thu, 1 Oct 2026 11:41:12 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 13C591F000FF; Thu, 1 Oct 2026 11:41:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1790854872; bh=OTQjaHyFzgR+M9iAe8/wiUOMwWAu1rzKJDK8Ma1143k=; h=Date:Subject:To:Cc:References:From:In-Reply-To; b=LTwFk0ZUeiqGzU59Wwjcl9Gq40g4HavoEq9B1yqQgL7vhd4Grw+hfiEa7Bj7X+q/f cfPlP+P21MXKYPL2otF3w/m8hCl5l+O9eK5Eg5vZlaoiYrb5o1ZSs3QTwG7XLwvjOG qr2ZJ+5YGPKFJ5CoObtvSyFnDO7zUbqPOgQuNK5YtDhZqyOysOsSuCiZu1RXzW6e98 N/C+3I+SfMy39sUykDQd5F5AURf2FskNYG8lOkGnFmvOBCRp71fK15GTc6HICJl25A AQwCcJ9VGR/XZW+zZ5rqk9hC1+VrtcJDiL5sVgZyGrX5hxLpulsNEvqJuHgQzSPhfp LMG5ulrygL63Q== Message-ID: Date: Thu, 1 Oct 2026 13:41:03 +0200 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH 1/4] selftests/mm: open pagemap and kpageflags once for check_huge() To: Zi Yan , Kiryl Shutsemau Cc: Andrew Morton , Lorenzo Stoakes , Mike Rapoport , Baolin Wang , Shuah Khan , "Kiryl Shutsemau (Meta)" , Barry Song , Dev Jain , Lance Yang , "Liam R . Howlett" , Michal Hocko , Nico Pache , Ryan Roberts , Suren Baghdasaryan , Usama Arif , Vlastimil Babka , Yeoreum Yun , linux-mm@kvack.org, linux-kselftest@vger.kernel.org, linux-kernel@vger.kernel.org, kernel-team@meta.com References: <20260929131521.153079-1-kirill@shutemov.name> <20260929131521.153079-2-kirill@shutemov.name> 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: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-Rspamd-Server: rspam05 X-Rspamd-Queue-Id: E9AB3180007 X-Stat-Signature: 4o6c7rbgaed3fct3n5ywroisgarce6cz X-Rspam-User: X-HE-Tag: 1790854872-495101 X-HE-Meta: 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 Ki8ZgsEb Xl6GVSZd9D29bzK85JNJpWqQkVlgxnKfxexZADpyg6qHQYLXN4XVCcvvTbmyn6zbogR+YSP+OuDC8SdLPTy19R1dLl4lB4vxapGTjLY0bbuN31ZV+KfHAdg6zn+ouI614cEA56Vd0UYk8E/HN158r5YDJoqG3vnYAnv0jiTdIsdvQihkhh+93UYoF9efu70jUBhzCa3s1o/UBsfTTwO6LA07fh5ylYRa8LZfdAwzeWnbSYaxtHbjHHssufzcMvBBTXMuHC4+175aJE0wqTJkKSrzhsR9tndZgJ2LHWmC1ifBrdCRW8AIbH7qa1aguLAxdd0n5KQKEZNj/zD7F2OHyAsuHP2KtwrmDp+bnJRuSYDey0Y0O4B9K7mutBiZ8uBgnqihGJUH955hwFPmk2DGkr6u53cRASPCp2f2k Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 9/29/26 17:28, Zi Yan wrote: > On 29 Sep 2026, at 9:15, Kiryl Shutsemau wrote: > >> From: "Kiryl Shutsemau (Meta)" >> >> check_huge_anon() and check_huge_file() open /proc/self/pagemap and >> /proc/kpageflags on every call and read the PMD size from sysfs on top. >> The khugepaged test calls them hundreds of times. >> >> Open both once and keep the descriptors. A pagemap descriptor is tied >> to the mm of the process that opened it, and the khugepaged fork() cases >> call check_huge() from the child, so reopen it when getpid() changes. >> >> Cache the PMD size in read_pmd_pagesize() as well. > > This part might be overlapping with Yeoreum’s another series[1]. > > [1] https://lore.kernel.org/all/20260921-fix_hpage_macro-v4-2-cdea4fc6ce3f@arm.com/ Yes, let's provide feedback there instead. -- Cheers, David