From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 48855606A325 for ; Tue, 10 Nov 2026 13:06:42 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=NU55q/eb Received: by kanga.kvack.org (Postfix) id 555306B05E2; Tue, 10 Nov 2026 08:06:41 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 504D86B05E4; Tue, 10 Nov 2026 08:06:41 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 3ACBE6B05E5; Tue, 10 Nov 2026 08:06:41 -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 119E16B05E2 for ; Tue, 10 Nov 2026 08:06:41 -0500 (EST) Received: from smtpin23.hostedemail.com (lb01a-stub [10.200.18.249]) by unirelay04.hostedemail.com (Postfix) with ESMTP id A13881A07A8 for ; Tue, 10 Nov 2026 13:06:40 +0000 (UTC) X-FDA: 85419233760.23.98D0199 Received: from sea.source.kernel.org (sea.source.kernel.org [172.234.252.31]) by imf15.hostedemail.com (Postfix) with ESMTP id D7023A0009 for ; Tue, 10 Nov 2026 13:06:38 +0000 (UTC) Authentication-Results: imf15.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20260515 header.b="NU55q/eb"; spf=pass (imf15.hostedemail.com: domain of david@kernel.org designates 172.234.252.31 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=1794315999; b=lER7NSdcmCw5a9WvImNGS7RfJduACiA9Hbu5dfB5LxGVjDTqzt1BtsYjlk8fqnFBTfgWa1 jp4XXw/SQF3TZsSeioYcSG1vbgPjYGvlDJdia6/NtGTVr6aIrWU7y0R3Ce51dJF07CP54T L/DZll1wglbSWLbthceT0MAI+Pw/H+o= ARC-Authentication-Results: i=1; imf15.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20260515 header.b="NU55q/eb"; spf=pass (imf15.hostedemail.com: domain of david@kernel.org designates 172.234.252.31 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=1794315999; 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=pK3VqSg4+AHRpwPeJDStu8IPDFJWjmvhTQ7EFdoCBFI=; b=tIADBnS2V5Yv3+rRRkyfoXfUlIvjzsSxvBagIV4ACu1dokID7Ett8E7kj/TwXaBPYmGALG XaVxuaT7WoTPMbXRJr61tHIZXNty1wlj6yBo//aSnD2twMigmtuWM7EyqRuOXOFIuSy/LU MaJpLnXFFjeQhayJIHz5EQHiJPLHjkk= Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) by sea.source.kernel.org (Postfix) with ESMTP id 0A6BF45E47; Tue, 10 Nov 2026 13:06:38 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 76A701F008A6; Tue, 10 Nov 2026 13:06:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1794315997; bh=pK3VqSg4+AHRpwPeJDStu8IPDFJWjmvhTQ7EFdoCBFI=; h=Date:Subject:To:Cc:References:From:In-Reply-To; b=NU55q/ebrSoPO0qK/eDjxfhlUabcj1z7A2K4fdJ6Ze+P1hzNcD5RAeiuTQ5FO70b9 3u88yzwzdOIOnM2d1uZDr0DPMejxdwfclnifYqLhDXsJ18TeyqgjxT2AgX6SdoczTA NPvAQ3zhsNAEsMKu03ieBTkG3jY0mUrsa0pf/X2fJO7SwkfZ/D2XeYbiJEw56YPa/Y iPhjXFYqoJU2gsASwx87ubQWCKhDzhWmEN9mg0yEZI4VZyzaOklsm/vXPW6FcN2IWy 3GRLwJUnjn6X6GE2IskbREYdSAgo1ZkY35cAzgObl0rDwzvL+2DkKiFaZCMNBCf/z/ PshgKYBHYFF7w== Message-ID: Date: Tue, 10 Nov 2026 14:04:43 +0100 X-Archived-By: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v3 5/6] mm: gup: introduce gup_unshared_pages() To: Yeoreum Yun , Rik van Riel Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, Jason Gunthorpe , John Hubbard , Peter Xu , Lorenzo Stoakes , "Liam R. Howlett" , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Michal Hocko , Andrew Morton , Yuan-Hao Hsu References: <20261109-refactor_gup_fast-v3-0-2aaef02df0e1@arm.com> <20261109-refactor_gup_fast-v3-5-2aaef02df0e1@arm.com> <7627c0d90188b581e7740bf8d17c8dd07b460f89.camel@surriel.com> 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: 7bit X-Spam-Status: No, score=-7.3 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_PASS,SPF_PASS,USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=4.0.1 X-Rspamd-Server: rspam07 X-Rspamd-Queue-Id: D7023A0009 X-Stat-Signature: hcerah4qsq9jzjzosyr1t7n3wyukrjw9 X-Rspam-User: X-HE-Tag: 1794315998-85680 X-HE-Meta: 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 Sy7k8FwX BG/Ch+BnnHeqKm0yD9SKN4s2O/emx1DQ750spWoEUZZ66zO/j5Pj7Q+YJldcaAD9BGToXWJ/PFlJccyWMkW31nvGGiTHPI3gvWkENqbmY3eLlz9NFaFf0WhcyORaVs9U7re2GiqEvDU7YYR+Ut2WkGYh/H8qkbavwtZXZSlRA1CNcjB1+KLotF1rZu1ktUIBD1fe0V58dIg2PFNOaiUt7MlM5DqTz7PRXj7p/6feQT6O3IxnJ96p3tqujNZT9gg+glo9bVIBwX7x/iuH7FJp4kKUYQX6pUdEWYPA4cefCWERpbONVCC4sGo0ZJg== Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: X-Spam-Checker-Version: SpamAssassin 4.0.1 (2024-03-26) on aws-us-west-2-korg-listserv-alma10-1 On 11/10/26 10:58, Yeoreum Yun wrote: > Hi Rik, > >> On Mon, 2026-11-09 at 12:32 +0000, Yeoreum Yun wrote: >>> This is preparatory patch to make gup_fast_pte_range() batchable. >>> >>> Introduce gup_unshared_pages() to count consecutive pages within a >>> folio >>> that do not require unsharing, and use it to implement >>> gup_must_unshare(). >>> >> Could gup_exclusive_pages() be a better name? > > Yes. This seems much better for me. I'll change it in next-spin. Not quite the right semantics. For pagecache folios we simply don't need unsharing in MAP_SHARED VMAs. That does not imply that these are exclusive. So it's all about "number of pages that don't need unsharing". Any idea for a fitting name ? :) -- Cheers, David