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 7F5C3CF3185 for ; Wed, 19 Nov 2025 10:13:50 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id C33FE6B0011; Wed, 19 Nov 2025 05:13:49 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id BE47D6B0022; Wed, 19 Nov 2025 05:13:49 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id AD3D86B002D; Wed, 19 Nov 2025 05:13:49 -0500 (EST) 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 97F3B6B0011 for ; Wed, 19 Nov 2025 05:13:49 -0500 (EST) Received: from smtpin29.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay09.hostedemail.com (Postfix) with ESMTP id 3C3E187B68 for ; Wed, 19 Nov 2025 10:13:49 +0000 (UTC) X-FDA: 84126945378.29.53A6F21 Received: from sea.source.kernel.org (sea.source.kernel.org [172.234.252.31]) by imf25.hostedemail.com (Postfix) with ESMTP id 7DDA3A000E for ; Wed, 19 Nov 2025 10:13:47 +0000 (UTC) Authentication-Results: imf25.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=LdGoDxJt; dmarc=pass (policy=quarantine) header.from=kernel.org; spf=pass (imf25.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=1763547227; 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=szA32RJyVbeRYTjJ7Ow9x4Y9um0eAlyuuRKChzXOWH8=; b=lzB9/liGkMePLTY9uhB+7rjFhFLsCWeRZQii0tgWKRl3HeD9cYCX24jyjrG9KxwdeVBICg grUfhDUA5q7nIOW2fssRyaaQWvLNoktiqsEVnjGKXt97wP3trQX/I6GYUggsVXAQq1YTyE xr8I8P6UJE8eTB/jT0pNvZOgWd99qZw= ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1763547227; a=rsa-sha256; cv=none; b=EPxPHlyc7XtQSr0YhFdHFgzXLVo+lBzT7aswnSqV5aadI1O1H47XyLYi8HqsVOPSqql/pE jonaMmxkviAVvK9qH5zGhhuE7pCwvqSjoDO8zKzFoYCMtWLuvTQuK+GHGvAtNgHB5p3NsN d7Pc3umTH9Mg0uRKk+lQ0OZHTU8d8PA= ARC-Authentication-Results: i=1; imf25.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=LdGoDxJt; dmarc=pass (policy=quarantine) header.from=kernel.org; spf=pass (imf25.hostedemail.com: domain of david@kernel.org designates 172.234.252.31 as permitted sender) smtp.mailfrom=david@kernel.org Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by sea.source.kernel.org (Postfix) with ESMTP id 8355C43FA7; Wed, 19 Nov 2025 10:13:46 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id AB52CC16AAE; Wed, 19 Nov 2025 10:13:40 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1763547226; bh=8IYxu/C3qrGid3n3xMVLRSBITnzao99XRln0ciNWneY=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=LdGoDxJt9h1Tlf1FCndkLyh+OwHFWpLYja9EnuhCaStGYdTO/u/3+Fxjm8oCvXk2/ E35KNa8rkDsQ4bPiZhB7BvC+7G9u3vv2O95UQNcf+uUOrfyBdK3uT+eewjqJwxMg6f O1rm2iLUscQJgkXdhNOc9AFc9kCFpZIhNjSzZINyqhCmWVFyFPOvsz8HJeqmQXW4+H s7XMLF+PxrmhzX0byFy0OOO5Djr+zth+JdHGDpKJGZ+dUbNfoMyOEIkvtSt3VTig0u DjN5MNM3mx4xWC+cutnpwm7m5sszHgWntNoXn6IOKKCqq/T/Yv6HJIdQv894sJyfel bVNiG5QRYn7SA== Message-ID: Date: Wed, 19 Nov 2025 11:13:37 +0100 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH 0/7] enable PT_RECLAIM on all 64-bit architectures To: Qi Zheng , Qi Zheng , will@kernel.org, aneesh.kumar@kernel.org, npiggin@gmail.com, peterz@infradead.org, dev.jain@arm.com, akpm@linux-foundation.org, ioworker0@gmail.com Cc: linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-alpha@vger.kernel.org, linux-snps-arc@lists.infradead.org, loongarch@lists.linux.dev, linux-mips@vger.kernel.org, linux-parisc@vger.kernel.org, linux-um@lists.infradead.org, Qi Zheng References: <83e88171-54cb-4112-a344-f6a7d7f13784@kernel.org> From: "David Hildenbrand (Red Hat)" Content-Language: en-US In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Stat-Signature: r3dgmd6xq5qe669kxebyf3soesezmc6f X-Rspam-User: X-Rspamd-Queue-Id: 7DDA3A000E X-Rspamd-Server: rspam10 X-HE-Tag: 1763547227-503812 X-HE-Meta: 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 lx88w+4P xu64sB4qQpmsYfUVvXHjvwzsImMMMXudLomiQ5YpQvy6fmzpNMT2Vc2PMzywELCnWHSrOPJLhQvq7xQOmGMffj5KpZMc+Giv6l7GpYSRkmPkOUYzUWqFZedxxQlUmlP4d8J1E1p0MU2QM/3MSlZLSEv57QGnflk5qspyDzzXRfWy1yuCuiJ3s/r3vBUfPaVHqPnsYDKAR1Xuef1Vz/OQnJgl/qrKc1z1SVsHuON/F2R07sVSaWF9L6VOI8A/Ekds3L5sC3/PfVZIJSAaNOKlcCLvjnMflQsONp3wJVFIxrrf/UwupOqIj7yG27N2NsfAh0/KXmukXCWj/64eG/nmmDPC7SxCCdHZ3f2PUKT328E+CMQZ9VEUiOq0zAe7UadMeE3/H0bB+JhrqLRDcINIdKAOtIm3YM0PJdBpZBiyuvs+n998+l0KPYVQgag== 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 18.11.25 12:53, Qi Zheng wrote: > > > On 11/18/25 12:53 AM, David Hildenbrand (Red Hat) wrote: >> On 14.11.25 12:11, Qi Zheng wrote: >>> From: Qi Zheng >>> >>> Hi all, >>> >>> This series aims to enable PT_RECLAIM on all 64-bit architectures. >>> >>> On a 64-bit system, madvise(MADV_DONTNEED) may cause a large number of >>> empty PTE >>> page table pages (such as 100GB+). To resolve this problem, we need to >>> enable >>> PT_RECLAIM, which depends on MMU_GATHER_RCU_TABLE_FREE. >>> >> >> Makes sense! >> >>> Therefore, this series first enables MMU_GATHER_RCU_TABLE_FREE on all >>> 64-bit >>> architectures, and finally makes PT_RECLAIM depend on >>> MMU_GATHER_RCU_TABLE_FREE >>> && 64BIT. This way, PT_RECLAIM can be enabled by default on all 64-bit >>> architectures. >> >> Could we then even go ahead and stop making PT_RECLAIM user-selectable? > > OK, will change to: Was more of a question: is there any scenario where we ran so far into issues with it? -- Cheers David