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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id E7FADEE2091 for ; Fri, 6 Feb 2026 11:59:37 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: Content-Type:In-Reply-To:From:References:Cc:To:Subject:MIME-Version:Date: Message-ID:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=5dYqXq1NRIfJySgnYSgnc1Tt2EdVmznlx20DFcIB6kE=; b=sILoHvEYJLP4VHtJ12qcOon5zH zDp6WnCCykzSAXdjh6d9soXKdAXe/QT3ZalArgvbe9wJzdBApAyL/UHIwXykOQVu/Yss0rixZPeCy giU1rjtjDzwZnWHqpaGo/LXIsum5CbLdPua1vjbWDkrtoSV8NmgD9TjWHKzsQQGMhdblpl+v66toB 55EJoQuqWwiyz83Kq6EIY12pW0ykRN+Yz6GdxfxJ+clXht4fNppFvzx9NwjFDTyuqqfZblkRz7R98 skqzq7ShW2YN3oTHVR5/VxPwGU7SmSjytWODrLSn77qIXOM3S+9LymfIzOF5lpcrGUHizvHMnASGX Ik2Tro6g==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98.2 #2 (Red Hat Linux)) id 1voKUr-0000000BGq0-2Jlm; Fri, 06 Feb 2026 11:59:37 +0000 Received: from out-170.mta1.migadu.com ([95.215.58.170]) by bombadil.infradead.org with esmtps (Exim 4.98.2 #2 (Red Hat Linux)) id 1voKUo-0000000BGny-0mRq for linux-um@lists.infradead.org; Fri, 06 Feb 2026 11:59:35 +0000 Message-ID: <53a1bbdd-26d1-454d-af06-169172278718@linux.dev> DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1770379151; 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=5dYqXq1NRIfJySgnYSgnc1Tt2EdVmznlx20DFcIB6kE=; b=Aalvtl60ATdjvtCv049X0heOLjC3Ne6UC4Jnw9CBdMvR2rHyEUK1QbvxylKB+AHtJsEUAU qvz+5iU0N8RA5zOq5wxvvGIq8Nn3kg8PMVar5v/lHabP5zzzP0j4LoFOtXGenQaBOxygN1 8rGXHcgmdNLdrCK3y2uriNFt0zpk2rs= Date: Fri, 6 Feb 2026 19:58:47 +0800 MIME-Version: 1.0 Subject: Re: [PATCH v4 7/8] mm: convert __HAVE_ARCH_TLB_REMOVE_TABLE to CONFIG_HAVE_ARCH_TLB_REMOVE_TABLE config To: "David Hildenbrand (Arm)" , andreas@gaisler.com, richard.weiyang@gmail.com, will@kernel.org, peterz@infradead.org, aneesh.kumar@kernel.org, npiggin@gmail.com, dev.jain@arm.com, ioworker0@gmail.com, linmag7@gmail.com, akpm@linux-foundation.org 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, sparclinux@vger.kernel.org, Qi Zheng References: <5ebfa3d4b56e63c6906bda5eccaa9f7194d3a86b.1769515122.git.zhengqi.arch@bytedance.com> <1663ae90-3247-4e12-a25a-049fc3281e19@linux.dev> <538fef61-3903-407e-8486-538a28b99e9d@kernel.org> X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. From: Qi Zheng In-Reply-To: <538fef61-3903-407e-8486-538a28b99e9d@kernel.org> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-Migadu-Flow: FLOW_OUT X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260206_035934_376453_83AD5F65 X-CRM114-Status: GOOD ( 12.46 ) X-BeenThere: linux-um@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-um" Errors-To: linux-um-bounces+linux-um=archiver.kernel.org@lists.infradead.org On 2/6/26 7:45 PM, David Hildenbrand (Arm) wrote: > On 2/6/26 12:13, Qi Zheng wrote: >> >> >> On 2/6/26 7:06 PM, David Hildenbrand (Arm) wrote: >>> On 1/27/26 13:13, Qi Zheng wrote: >>>> From: Qi Zheng >>>> >>>> For architectures that define __HAVE_ARCH_TLB_REMOVE_TABLE, the page >>>> tables at the pmd/pud level are generally not of struct ptdesc type, >>>> and >>>> do not have pt_rcu_head member, thus these architectures cannot support >>>> PT_RECLAIM. >>>> >>>> In preparation for enabling PT_RECLAIM on more architectures, convert >>>> __HAVE_ARCH_TLB_REMOVE_TABLE to CONFIG_HAVE_ARCH_TLB_REMOVE_TABLE >>>> config, >>>> so that we can make conditional judgments in Kconfig. >>>> >>>> Signed-off-by: Qi Zheng >>>> --- >>>>   arch/powerpc/Kconfig            | 1 + >>>>   arch/powerpc/include/asm/tlb.h  | 1 - >>>>   arch/sparc/Kconfig              | 1 + >>>>   arch/sparc/include/asm/tlb_64.h | 1 - >>>>   include/asm-generic/tlb.h       | 2 +- >>>>   mm/Kconfig                      | 3 +++ >>>>   6 files changed, 6 insertions(+), 3 deletions(-) >>>> >>>> diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig >>>> index 9537a61ebae02..b47aa8fd62742 100644 >>>> --- a/arch/powerpc/Kconfig >>>> +++ b/arch/powerpc/Kconfig >>>> @@ -304,6 +304,7 @@ config PPC >>>>       select LOCK_MM_AND_FIND_VMA >>>>       select MMU_GATHER_PAGE_SIZE >>>>       select MMU_GATHER_RCU_TABLE_FREE >>>> +    select HAVE_ARCH_TLB_REMOVE_TABLE >>>>       select MMU_GATHER_MERGE_VMAS >>>>       select MMU_LAZY_TLB_SHOOTDOWN        if PPC_BOOK3S_64 >>>>       select MODULES_USE_ELF_RELA >>>> diff --git a/arch/powerpc/include/asm/tlb.h b/arch/powerpc/include/ >>>> asm/tlb.h >>>> index 2058e8d3e0138..1ca7d4c4b90db 100644 >>>> --- a/arch/powerpc/include/asm/tlb.h >>>> +++ b/arch/powerpc/include/asm/tlb.h >>>> @@ -37,7 +37,6 @@ extern void tlb_flush(struct mmu_gather *tlb); >>>>    */ >>>>   #define tlb_needs_table_invalidate()    radix_enabled() >>>> -#define __HAVE_ARCH_TLB_REMOVE_TABLE >>>>   /* Get the generic bits... */ >>>>   #include >>>> diff --git a/arch/sparc/Kconfig b/arch/sparc/Kconfig >>>> index a630d373e6453..25fa2908d6152 100644 >>>> --- a/arch/sparc/Kconfig >>>> +++ b/arch/sparc/Kconfig >>>> @@ -74,6 +74,7 @@ config SPARC64 >>>>       select HAVE_KRETPROBES >>>>       select HAVE_KPROBES >>>>       select MMU_GATHER_RCU_TABLE_FREE if SMP >>>> +    select HAVE_ARCH_TLB_REMOVE_TABLE if SMP >>> >>> Why the SMP? At least in tlb_64.h, it was not protected by SMP IIUC. >> >> Ah, It's just simply aligned with the MMU_GATHER_RCU_TABLE_FREE above. > > But does that work as expected for !SMP? In the case of !SMP, tlb_remove_table() will not be called: static inline void pgtable_free_tlb(struct mmu_gather *tlb, void *table, bool is_page) { pgtable_free(table, is_page); } so I think it's okay to only select it in case of SMP. >