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 7B19BC79FA1 for ; Tue, 8 Sep 2026 10:42:06 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 750976B008C; Tue, 8 Sep 2026 06:42:05 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 700386B0092; Tue, 8 Sep 2026 06:42:05 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 5A3F46B009F; Tue, 8 Sep 2026 06:42:05 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0017.hostedemail.com [216.40.44.17]) by kanga.kvack.org (Postfix) with ESMTP id 2DD8C6B008C for ; Tue, 8 Sep 2026 06:42:05 -0400 (EDT) Received: from smtpin28.hostedemail.com (lb01a-stub [10.200.18.249]) by unirelay07.hostedemail.com (Postfix) with ESMTP id B321C1604AB for ; Tue, 8 Sep 2026 10:42:04 +0000 (UTC) X-FDA: 85190254968.28.FCFCBB8 Received: from sea.source.kernel.org (sea.source.kernel.org [172.234.252.31]) by imf19.hostedemail.com (Postfix) with ESMTP id E9D8D1A0003 for ; Tue, 8 Sep 2026 10:42:02 +0000 (UTC) Authentication-Results: imf19.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20260515 header.b=Ts+2oT9g; dmarc=pass (policy=quarantine) header.from=kernel.org; spf=pass (imf19.hostedemail.com: domain of david@kernel.org designates 172.234.252.31 as permitted sender) smtp.mailfrom=david@kernel.org ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1788864123; 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=AXqs15IsRXVps+8wsgrFLas5JJDnQxYsS/CgwzQnLIQ=; b=AKVDLIy2yjpHhMlD19CgG63qHGEAnC9H78UBt5pz/LfWwIKCfw1YqZXzPFqz1qDI0j1OOK cYcljnrRpBttBjOuS3UgVkerWqm4f/ILQfdNNQhPWqSHZGIdAXZ2Rq2Yv0k3VgtMQnCiKC TQEinS6LbyQs9Dx+j6EWOwOK1x50MYU= ARC-Authentication-Results: i=1; imf19.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20260515 header.b=Ts+2oT9g; dmarc=pass (policy=quarantine) header.from=kernel.org; spf=pass (imf19.hostedemail.com: domain of david@kernel.org designates 172.234.252.31 as permitted sender) smtp.mailfrom=david@kernel.org ARC-Seal: i=1; a=rsa-sha256; d=hostedemail.com; s=arc-20220608; cv=none; t=1788864123; b=RCFvphkIXIWPHLcKoFocM92M/ZS5JlmJEXTX53/jsPer5/jILS97VfLpJwL4Mdpen09qha n+6CpmbV90ttOAfoKixME5iNASm6ouYDqms58m0jvTmRAbcId4PWWtLpyjaVn3l3TWk8qi IPWYwfIt6zthp1pkMe3X/1OuQr3/fVM= Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) by sea.source.kernel.org (Postfix) with ESMTP id 24EF6432A7; Tue, 8 Sep 2026 10:42:02 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 217E41F00A3D; Tue, 8 Sep 2026 10:41:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1788864122; bh=AXqs15IsRXVps+8wsgrFLas5JJDnQxYsS/CgwzQnLIQ=; h=Date:Subject:To:Cc:References:From:In-Reply-To; b=Ts+2oT9g4dJ8E/yRTT4+ymW5CL2YgT30NOeH0+37YvojcObvX/+LwiXW6viFmv/li Kn/t6Lg4LFnq79JAr859FgsU7XvspRgAlKzQDkHtua6XY3i7HrqNpsuI6yUjozNycM JcyhwJZEj+qrzDkXpIzT9fXTaxcF7dV3EaR4PkuYHujkwfqFjLqoMiGIDMqZrCvGzq ezFSUXNF8AWUnyxoSHcP9zcnY8PW8YHaGuA812enyhr5Vh47ituyy+VP+uj/6KSU9x yQhY1Zlg5QuRgwIkMWdo590auZy/dtyijHs98kn/Dz9CNQ1YSj3uTLFHhqSjmusAlX KK7OnJtFUhmnQ== Message-ID: <2b0f5877-e71a-4824-adeb-5af2dd8b0269@kernel.org> Date: Tue, 8 Sep 2026 12:41:48 +0200 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v3 4/6] mm/vmalloc: make set_area_direct_map HUGE_VMAP friendly To: "Mike Rapoport (Microsoft)" , Andrew Morton Cc: =?UTF-8?Q?Adrian_Barna=C5=9B?= , Albert Ou , Alexander Gordeev , Alexandre Ghiti , Andy Lutomirski , Borislav Petkov , Brendan Jackman , Catalin Marinas , Christian Borntraeger , Dave Hansen , Gerald Schaefer , Heiko Carstens , Huacai Chen , Ingo Molnar , Len Brown , Palmer Dabbelt , Paul Walmsley , Pavel Machek , Peter Zijlstra , "H. Peter Anvin" , "Rafael J. Wysocki" , Ryan Roberts , Sven Schnelle , Thomas Gleixner , Uladzislau Rezki , Vasily Gorbik , WANG Xuerui , Will Deacon , x86@kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-pm@vger.kernel.org, linux-riscv@lists.infradead.org, linux-s390@vger.kernel.org, loongarch@lists.linux.dev References: <20260903-execmem-set-vm-perms-v0-2-v3-0-949b64a9f755@kernel.org> <20260903-execmem-set-vm-perms-v0-2-v3-4-949b64a9f755@kernel.org> 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: <20260903-execmem-set-vm-perms-v0-2-v3-4-949b64a9f755@kernel.org> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-Rspamd-Server: rspam08 X-Rspamd-Queue-Id: E9D8D1A0003 X-Stat-Signature: etdjybgqaysdnhykimsyz9g58kwosfbh X-Rspam-User: X-HE-Tag: 1788864122-263805 X-HE-Meta: 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 dNXixJfv 0/hTtGQfcBGY1baU1MYYmHmVrwGjHtX0c6Gj9FhlhiX+vn0dIHa/zc2n6+XARsfz3PPj8Ilhlt2exSAoszgOLHtHX+QKyl/BEGgNfNtDUgkESq2zQ+Lww3urX5/oM4CVgQwuYpYYOpYcguCrVDhuyaB8iYxlruNKWnFIfKZd/tW+3oUy7n7x3jZ5u17JvBrtxaBoBtq5zTVt1cfX173KDWb7b4xPNCzJIzpplyWN1Spr+qZiOJiG34tjQUig1NBJTMIUP3OlnAqhJf8E8BAzW+oKtN7+32xszTB4JMLymwJ6N0VSaI9Pp9FaUGZafDzBCT6vCuJ1xETXrbLo= Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 9/3/26 11:28, Mike Rapoport (Microsoft) wrote: > set_area_direct_map() always updates direct map alias permissions in > single page increments. > > For HUGE_VMAP areas it's suboptimal. Not only the loop in > set_area_direct_map() needlessly has more iterations (e.g times 512 on > x86), but it also causes fragmentation of the direct map that could be > avoided for the HUGE_VMAP areas populated with large pages. > > All pages in an area are always of the same order: either same-order > large pages when VM_ALLOW_HUGE_VMAP is set and all huge pages were > successfully allocated, or order-0 page when VM_ALLOW_HUGE_VMAP is > cleared or when huge pages allocation fails and fallback path is taken. > > Instead of updating the direct map permissions for every order-0 page in > an area, use the area's page_order as the loop increment and update the > large pages in one call to set_direct_map_{invalid,default}_noflush(). > > Signed-off-by: Mike Rapoport (Microsoft) > --- > mm/vmalloc.c | 13 ++++++++----- > 1 file changed, 8 insertions(+), 5 deletions(-) > > diff --git a/mm/vmalloc.c b/mm/vmalloc.c > index 5506b180f5c27..6ed6c160abed7 100644 > --- a/mm/vmalloc.c > +++ b/mm/vmalloc.c > @@ -3367,12 +3367,15 @@ static inline void set_area_direct_map(const struct vm_struct *area, > int (*set_direct_map)(struct page *page, > unsigned int nr)) > { > - unsigned long i; > + unsigned int nr = (1U << vm_area_page_order(area)); > + > + for (unsigned long i = 0; i < area->nr_pages; i += nr) { > + if (page_address(area->pages[i])) { > + int err = set_direct_map(area->pages[i], nr); Do we really expect some pages to have a directmap and others not? -- Cheers, David