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 B1C72CF31B5 for ; Wed, 19 Nov 2025 12:16:18 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 147506B00A8; Wed, 19 Nov 2025 07:16:18 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 0F74D6B00A9; Wed, 19 Nov 2025 07:16:18 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id F28896B00AA; Wed, 19 Nov 2025 07:16:17 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0014.hostedemail.com [216.40.44.14]) by kanga.kvack.org (Postfix) with ESMTP id E0C2A6B00A8 for ; Wed, 19 Nov 2025 07:16:17 -0500 (EST) Received: from smtpin01.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay01.hostedemail.com (Postfix) with ESMTP id 264A04DDC3 for ; Wed, 19 Nov 2025 12:16:15 +0000 (UTC) X-FDA: 84127253910.01.ED8F6C7 Received: from out-181.mta0.migadu.com (out-181.mta0.migadu.com [91.218.175.181]) by imf10.hostedemail.com (Postfix) with ESMTP id BB4A8C0011 for ; Wed, 19 Nov 2025 12:16:12 +0000 (UTC) Authentication-Results: imf10.hostedemail.com; dkim=pass header.d=linux.dev header.s=key1 header.b=AVtUPokb; spf=pass (imf10.hostedemail.com: domain of qi.zheng@linux.dev designates 91.218.175.181 as permitted sender) smtp.mailfrom=qi.zheng@linux.dev; dmarc=pass (policy=none) header.from=linux.dev ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1763554572; 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=T8UxEgfEvYYIYjqonyzaX1YNHYFvCPlixYyfl5K/5Us=; b=rbQ90m3saFEesGTU8SLI7qNQjul2EJz9gJ9C7Z6q8iZ+dUBhweUcw8TblY0rF8iPeEeBo4 uOpCjdJ/0jZi2/RJ0L6MIWYraIhLNJiqwS8wL0ijRyMbwNTSEg4Cf3/xAHXKRgKbC8p5oQ 5kR8p3ItHlSrB9DfeVbXhF/4S/DxJSw= ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1763554572; a=rsa-sha256; cv=none; b=7AEidEgdk/4Jc3nfVNP3L3qL1nshC7PSTG7iPPEXrvlJh4I9vs8EH65c0mECnf4lV5n0nI riMFSMphv+YjtII78ExbZ3sOoEH7i0RO3Qpsz/1igaI4dT7BsopLzLbqBnwUfP/91DHWG6 qgwB8vVR4PATrOb1KSm7py3mDFG4/4E= ARC-Authentication-Results: i=1; imf10.hostedemail.com; dkim=pass header.d=linux.dev header.s=key1 header.b=AVtUPokb; spf=pass (imf10.hostedemail.com: domain of qi.zheng@linux.dev designates 91.218.175.181 as permitted sender) smtp.mailfrom=qi.zheng@linux.dev; dmarc=pass (policy=none) header.from=linux.dev Message-ID: <6e6d8390-1f9e-40cf-949d-168160fa9a15@linux.dev> DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1763554567; 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; bh=T8UxEgfEvYYIYjqonyzaX1YNHYFvCPlixYyfl5K/5Us=; b=AVtUPokbskA2fxW7sCPAzJUrWf8TDNbPt/WdsQfOCSbGOGvqVUig5Chd70lHJMkyln4ufj X6Bg1RKVDftg0vFjwYVYCXvoFKw63N958H75bSqPHgoSBbSpEmPqQpJlqP6Lz5U8HFdbCb XKACOfahN120NBnxDteAgU+KBrLLN4I= Date: Wed, 19 Nov 2025 20:15:58 +0800 MIME-Version: 1.0 Subject: Re: [PATCH v2 7/7] mm: enable PT_RECLAIM on all 64-bit architectures To: "David Hildenbrand (Red Hat)" , will@kernel.org, aneesh.kumar@kernel.org, npiggin@gmail.com, peterz@infradead.org, dev.jain@arm.com, akpm@linux-foundation.org, ioworker0@gmail.com, linmag7@gmail.com Cc: linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, linux-alpha@vger.kernel.org, loongarch@lists.linux.dev, linux-mips@vger.kernel.org, linux-parisc@vger.kernel.org, linux-um@lists.infradead.org, Qi Zheng References: <9b55623a-4606-4610-a0fe-55b8cd6b95e7@kernel.org> X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. From: Qi Zheng In-Reply-To: <9b55623a-4606-4610-a0fe-55b8cd6b95e7@kernel.org> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-Migadu-Flow: FLOW_OUT X-Rspamd-Server: rspam04 X-Rspamd-Queue-Id: BB4A8C0011 X-Stat-Signature: cd6tdainxw6d7eerajjnnet95yrb3swc X-Rspam-User: X-HE-Tag: 1763554572-218021 X-HE-Meta: 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 fQwhsa2S dF7rKyZ2nN2/8s5hK74wvrfaLrnRqxoXM+wMQfz2tZunFLKztWUi6FHVmmWC/z+xuE1xFIvj7bB+HHwfpq3FgzBr4oMu7RArgnkkQ9YH5GrkOTll+l3pKGC4nb22qrhihhpTuG439qfwplZR3PG/j6OKT8qI/MnK56h2yP+zMEmgV3wvdeLw0X73zeQoepHmcraePLdD1A/1qv+l0QsJhj4b71TsYCHQ79mxz9PDWTxJOpdh48+BqOuWusAT3Yr3/kdg0mOA+nq1u9AIsmMiLGJvrhkAew9688/AtNaWmNTBbI9URBT85ICuFqA== 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 11/19/25 7:38 PM, David Hildenbrand (Red Hat) wrote: > On 19.11.25 08:31, Qi Zheng wrote: >> From: Qi Zheng >> >> Now, the MMU_GATHER_RCU_TABLE_FREE is enabled on all 64-bit >> architectures, >> so make PT_RECLAIM depend on 64BIT, thereby enabling PT_RECLAIM on all >> 64-bit architectures. >> >> Signed-off-by: Qi Zheng >> --- >>   arch/x86/Kconfig | 1 - >>   mm/Kconfig       | 9 ++------- >>   2 files changed, 2 insertions(+), 8 deletions(-) >> >> diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig >> index eac2e86056902..96bff81fd4787 100644 >> --- a/arch/x86/Kconfig >> +++ b/arch/x86/Kconfig >> @@ -330,7 +330,6 @@ config X86 >>       select FUNCTION_ALIGNMENT_4B >>       imply IMA_SECURE_AND_OR_TRUSTED_BOOT    if EFI >>       select HAVE_DYNAMIC_FTRACE_NO_PATCHABLE >> -    select ARCH_SUPPORTS_PT_RECLAIM        if X86_64 >>       select ARCH_SUPPORTS_SCHED_SMT        if SMP >>       select SCHED_SMT            if SMP >>       select ARCH_SUPPORTS_SCHED_CLUSTER    if SMP >> diff --git a/mm/Kconfig b/mm/Kconfig >> index d548976d0e0ad..94eec5c0cad96 100644 >> --- a/mm/Kconfig >> +++ b/mm/Kconfig >> @@ -1448,14 +1448,9 @@ config ARCH_HAS_USER_SHADOW_STACK >>         The architecture has hardware support for userspace shadow call >>             stacks (eg, x86 CET, arm64 GCS or RISC-V Zicfiss). >> -config ARCH_SUPPORTS_PT_RECLAIM >> -    def_bool n >> - >>   config PT_RECLAIM >> -    bool "reclaim empty user page table pages" >> -    default y >> -    depends on ARCH_SUPPORTS_PT_RECLAIM && MMU && SMP >> -    select MMU_GATHER_RCU_TABLE_FREE >> +    def_bool y >> +    depends on 64BIT > > As discussed in the other thread, likely > > config PT_RECLAIM >     def_bool y >     depends on MMU_GATHER_RCU_TABLE_FREE && 64BIT > > Could be nice, and if possible even dropping the 64BIT limitation as > well if there is no need to. I think it's ok to drop the 64BIT limitation. There should be some 32-bit architectures that already enable MMU_GATHER_RCU_TABLE_FREE. > >