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 X-Spam-Level: X-Spam-Status: No, score=-8.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7D434C433EF for ; Thu, 16 Sep 2021 16:31:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 65DCE613B3 for ; Thu, 16 Sep 2021 16:31:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S241934AbhIPQdN (ORCPT ); Thu, 16 Sep 2021 12:33:13 -0400 Received: from mail.kernel.org ([198.145.29.99]:37484 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S241228AbhIPQZL (ORCPT ); Thu, 16 Sep 2021 12:25:11 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 7040F613C8; Thu, 16 Sep 2021 16:16:32 +0000 (UTC) Date: Thu, 16 Sep 2021 17:16:29 +0100 From: Catalin Marinas To: Anshuman Khandual Cc: linux-arm-kernel@lists.infradead.org, mark.rutland@arm.com, suzuki.poulose@arm.com, Will Deacon , linux-kernel@vger.kernel.org Subject: Re: [PATCH] arm64/mm: Add pud_sect_supported() Message-ID: References: <1631677459-28383-1-git-send-email-anshuman.khandual@arm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1631677459-28383-1-git-send-email-anshuman.khandual@arm.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Sep 15, 2021 at 09:14:19AM +0530, Anshuman Khandual wrote: > diff --git a/arch/arm64/mm/hugetlbpage.c b/arch/arm64/mm/hugetlbpage.c > index 23505fc35324..641854f0e8ee 100644 > --- a/arch/arm64/mm/hugetlbpage.c > +++ b/arch/arm64/mm/hugetlbpage.c > @@ -40,11 +40,10 @@ void __init arm64_hugetlb_cma_reserve(void) > { > int order; > > -#ifdef CONFIG_ARM64_4K_PAGES > - order = PUD_SHIFT - PAGE_SHIFT; > -#else > - order = CONT_PMD_SHIFT + PMD_SHIFT - PAGE_SHIFT; > -#endif > + if (pud_sect_supported()) > + order = PUD_SHIFT - PAGE_SHIFT; > + else > + order = CONT_PMD_SHIFT + PMD_SHIFT - PAGE_SHIFT; > /* > * HugeTLB CMA reservation is required for gigantic > * huge pages which could not be allocated via the > @@ -62,8 +61,9 @@ bool arch_hugetlb_migration_supported(struct hstate *h) > size_t pagesize = huge_page_size(h); > > switch (pagesize) { > -#ifdef CONFIG_ARM64_4K_PAGES > +#ifndef __PAGETABLE_PUD_FOLDED > case PUD_SIZE: > + return pud_sect_supported(); > #endif > case PMD_SIZE: > case CONT_PMD_SIZE: Is this the same thing? With 4K pages and 3-levels (39-bit VA), the PUD is folded but we do have a valid PUD_SIZE == PGDIR_SIZE and different from PMD_SIZE. Do we disallow section mappings at the top level in this case? If not, we should have check for __PAGETABLE_PMD_FOLDED instead. > @@ -126,8 +126,11 @@ static inline int num_contig_ptes(unsigned long size, size_t *pgsize) > *pgsize = size; > > switch (size) { > -#ifdef CONFIG_ARM64_4K_PAGES > +#ifndef __PAGETABLE_PUD_FOLDED > case PUD_SIZE: > + if (pud_sect_supported()) > + contig_ptes = 1; > + break; > #endif > case PMD_SIZE: > contig_ptes = 1; Same here. > @@ -489,9 +492,9 @@ void huge_ptep_clear_flush(struct vm_area_struct *vma, > > static int __init hugetlbpage_init(void) > { > -#ifdef CONFIG_ARM64_4K_PAGES > - hugetlb_add_hstate(PUD_SHIFT - PAGE_SHIFT); > -#endif > + if (pud_sect_supported()) > + hugetlb_add_hstate(PUD_SHIFT - PAGE_SHIFT); > + > hugetlb_add_hstate(CONT_PMD_SHIFT - PAGE_SHIFT); > hugetlb_add_hstate(PMD_SHIFT - PAGE_SHIFT); > hugetlb_add_hstate(CONT_PTE_SHIFT - PAGE_SHIFT); > @@ -503,8 +506,9 @@ arch_initcall(hugetlbpage_init); > bool __init arch_hugetlb_valid_size(unsigned long size) > { > switch (size) { > -#ifdef CONFIG_ARM64_4K_PAGES > +#ifndef __PAGETABLE_PUD_FOLDED > case PUD_SIZE: > + return pud_sect_supported(); > #endif > case CONT_PMD_SIZE: > case PMD_SIZE: And here. -- Catalin