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 6BF35CCD193 for ; Sat, 18 Oct 2025 09:53:15 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 7BD5E8E0006; Sat, 18 Oct 2025 05:53:14 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 795388E0002; Sat, 18 Oct 2025 05:53:14 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 6AB3F8E0006; Sat, 18 Oct 2025 05:53:14 -0400 (EDT) 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 58A2C8E0002 for ; Sat, 18 Oct 2025 05:53:14 -0400 (EDT) Received: from smtpin27.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay04.hostedemail.com (Postfix) with ESMTP id 0A2D41A040C for ; Sat, 18 Oct 2025 09:53:14 +0000 (UTC) X-FDA: 84010771908.27.C12C7D6 Received: from sea.source.kernel.org (sea.source.kernel.org [172.234.252.31]) by imf25.hostedemail.com (Postfix) with ESMTP id 39E59A0005 for ; Sat, 18 Oct 2025 09:53:12 +0000 (UTC) Authentication-Results: imf25.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=PVM7dGcE; dmarc=pass (policy=quarantine) header.from=kernel.org; spf=pass (imf25.hostedemail.com: domain of rppt@kernel.org designates 172.234.252.31 as permitted sender) smtp.mailfrom=rppt@kernel.org ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1760781192; 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: in-reply-to:in-reply-to:references:references:dkim-signature; bh=a5m34w+YJySeDMAg4oYbPewI29W2a9gKFrrQ6A/Z98U=; b=8Rw+wXC1KJngTrDVL9j0RTri5P4UlJcvcszHL9kO6j1QNsBaNj5DDCA2k6Ct8oswTvFnDT pNHpbAmbZBLyzC/E/NAZUdTbOdqNzRVWrAPSFq9P6WR+Bt/iO8n7ylRaSgsoYR4ekALggy rTcAF5BX4szT2apg0zRTQ3mKq5OWEvE= ARC-Authentication-Results: i=1; imf25.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=PVM7dGcE; dmarc=pass (policy=quarantine) header.from=kernel.org; spf=pass (imf25.hostedemail.com: domain of rppt@kernel.org designates 172.234.252.31 as permitted sender) smtp.mailfrom=rppt@kernel.org ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1760781192; a=rsa-sha256; cv=none; b=qREAUDQVo8VDrbmsccdphIzmqPqxpidHZa4/ikro/DyFEUS5Xi51aq53dugDlqwBMtziDQ 7b3XJBl0doWpSf88EZkCl+b7G9lB0gOf3zOehi3ogij8d8RhgohrGTwHrJag5gLqppmFbq RMuxg+HSlXiZAWhCA2YNcl0ng5nEIA0= Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by sea.source.kernel.org (Postfix) with ESMTP id A913045000; Sat, 18 Oct 2025 09:53:10 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id A979DC113D0; Sat, 18 Oct 2025 09:52:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1760781190; bh=bOSmYzha9caq7PhodKTKcCoPiLt+2LlIcLfZyClR6tI=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=PVM7dGcEYXCuz8kq+FQlif5GkokSxvCHTzAFAGwTnR8/6weD/vKEUQASmePsYFC3h +euqjGf0PMyAFk0ZJUt5YM7wZxnuKR0UvscN4IWjm71nso3T24TfhImRIqQfyI4ss6 cv+7XmuLUObCGPTep6i88M7y6u+ifbhyfVbe1BHS4zD5ALzPNDk/kx15zhKRwL0t27 dMmFhLM5KTioGdUJieNshqGCPzeMSFbHvJviFEJxzNeYiuG1A5BFkxDb8ilKL2vLrA 8jv3n05kf1if0vj2NPnC/QhhCj3HuD1WtyN73Zhx+EyOOZxPqW3faoSHxWvYSohg6r KlyEFQZJR/qhA== Date: Sat, 18 Oct 2025 12:52:55 +0300 From: Mike Rapoport To: Kevin Brodsky Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, Alexander Gordeev , Andreas Larsson , Andrew Morton , Boris Ostrovsky , Borislav Petkov , Catalin Marinas , Christophe Leroy , Dave Hansen , David Hildenbrand , "David S. Miller" , "H. Peter Anvin" , Ingo Molnar , Jann Horn , Juergen Gross , "Liam R. Howlett" , Lorenzo Stoakes , Madhavan Srinivasan , Michael Ellerman , Michal Hocko , Nicholas Piggin , Peter Zijlstra , Ryan Roberts , Suren Baghdasaryan , Thomas Gleixner , Vlastimil Babka , Will Deacon , Yeoreum Yun , linux-arm-kernel@lists.infradead.org, linuxppc-dev@lists.ozlabs.org, sparclinux@vger.kernel.org, xen-devel@lists.xenproject.org, x86@kernel.org Subject: Re: [PATCH v3 05/13] mm: introduce CONFIG_ARCH_LAZY_MMU Message-ID: References: <20251015082727.2395128-1-kevin.brodsky@arm.com> <20251015082727.2395128-6-kevin.brodsky@arm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20251015082727.2395128-6-kevin.brodsky@arm.com> X-Rspam-User: X-Rspamd-Queue-Id: 39E59A0005 X-Rspamd-Server: rspam03 X-Stat-Signature: 4pr1t7dnni6kkcwqcg4mbpp5jutiqoii X-HE-Tag: 1760781192-351970 X-HE-Meta: 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 uTiAIrXz YBRZkN/0EzSgKNAsVDWEQs6aXQaXEUK/pv7qhbbiYJIygPB4xJBeJhpIMeUwXnraYECvMM/ljw75fxQ88sYLNrir68wwEUw3ga/7HW8dRK7jvkrMVNWPTgZrzHaTQMTU8Ftab6uDSIldfH5mwbYekXCe2CMw53xe+lKM1RYE5x8EkTs3mX6fD5fTJc2Q2bgzGEtGO9tNd7iPDNKKmQi9/3rTvWyCtIJc/xEHTWSX6rNOgfcDh0DwdpQGKVlQSU4TsVGqKG6Ez/QODNEtoj1nrt6+67bDvgSCgaYjZD2B2yqQhRViSyR7s6twE4tWthuNnuuvnlcHYGrb2XAQk5sz+mP+WN+sWAXLsuIsYYy0FM3rRyQaapLUp7Q+jBqzd2OPe3zdZz3/xyUBnUOI= 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 Wed, Oct 15, 2025 at 09:27:19AM +0100, Kevin Brodsky wrote: > Architectures currently opt in for implementing lazy_mmu helpers by > defining __HAVE_ARCH_ENTER_LAZY_MMU_MODE. > > In preparation for introducing a generic lazy_mmu layer that will > require storage in task_struct, let's switch to a cleaner approach: > instead of defining a macro, select a CONFIG option. > > This patch introduces CONFIG_ARCH_LAZY_MMU and has each arch select > it when it implements lazy_mmu helpers. > __HAVE_ARCH_ENTER_LAZY_MMU_MODE is removed and > relies on the new CONFIG instead. > > On x86, lazy_mmu helpers are only implemented if PARAVIRT_XXL is > selected. This creates some complications in arch/x86/boot/, because > a few files manually undefine PARAVIRT* options. As a result > does not define the lazy_mmu helpers, but this > breaks the build as only defines them if > !CONFIG_ARCH_LAZY_MMU. There does not seem to be a clean way out of > this - let's just undefine that new CONFIG too. > > Signed-off-by: Kevin Brodsky > --- ... > @@ -231,7 +231,7 @@ static inline int pmd_dirty(pmd_t pmd) > * held, but for kernel PTE updates, no lock is held). Nesting is not permitted > * and the mode cannot be used in interrupt context. > */ > -#ifndef __HAVE_ARCH_ENTER_LAZY_MMU_MODE > +#ifndef CONFIG_ARCH_LAZY_MMU > static inline void arch_enter_lazy_mmu_mode(void) {} > static inline void arch_leave_lazy_mmu_mode(void) {} > static inline void arch_flush_lazy_mmu_mode(void) {} > diff --git a/mm/Kconfig b/mm/Kconfig > index 0e26f4fc8717..2fdcb42ca1a1 100644 > --- a/mm/Kconfig > +++ b/mm/Kconfig > @@ -1372,6 +1372,9 @@ config PT_RECLAIM > config FIND_NORMAL_PAGE > def_bool n > > +config ARCH_LAZY_MMU > + bool > + I think a better name would be ARCH_HAS_LAZY_MMU and the config option fits better to arch/Kconfig. > source "mm/damon/Kconfig" > > endmenu > -- > 2.47.0 > -- Sincerely yours, Mike.