Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756079AbbBFOvp (ORCPT ); Fri, 6 Feb 2015 09:51:45 -0500 Received: from mga09.intel.com ([134.134.136.24]:47276 "EHLO mga09.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755882AbbBFOvm (ORCPT ); Fri, 6 Feb 2015 09:51:42 -0500 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.97,862,1389772800"; d="scan'208";a="450830911" From: "Kirill A. Shutemov" To: Andrew Morton Cc: linux-mm@kvack.org, linux-kernel@vger.kernel.org, "Kirill A. Shutemov" , David Howells Subject: [PATCHv2, RESEND 04/19] frv: mark PUD and PMD folded Date: Fri, 6 Feb 2015 16:50:49 +0200 Message-Id: <1423234264-197684-5-git-send-email-kirill.shutemov@linux.intel.com> X-Mailer: git-send-email 2.1.4 In-Reply-To: <1423234264-197684-1-git-send-email-kirill.shutemov@linux.intel.com> References: <1423234264-197684-1-git-send-email-kirill.shutemov@linux.intel.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2262 Lines: 62 Core mm expects __PAGETABLE_{PUD,PMD}_FOLDED to be defined if these page table levels folded. Signed-off-by: Kirill A. Shutemov Cc: David Howells Tested-by: Guenter Roeck --- I've implemented accounting for pmd page tables as we have for pte (see mm->nr_ptes). It's requires a new counter in mm_struct: mm->nr_pmds. But the feature doesn't make any sense if an architecture has PMD level folded and it would be nice get rid of the counter in this case. The problem is that we cannot use __PAGETABLE_PMD_FOLDED in due to circular dependencies: -> -> In most cases wants to get definition of struct page and struct vm_area_struct. I've tried to split mm_struct into separate header file to be able to user there. But it doesn't fly on some architectures, like ARM: it wants mm_struct to implement tlb flushing. I don't see how to fix it without massive de-inlining or coverting a lot for inline functions to macros. This is other approach: expose number of page tables in use via Kconfig and use it in instead of __PAGETABLE_PMD_FOLDED from . --- arch/frv/include/asm/pgtable.h | 2 ++ 1 file changed, 2 insertions(+) diff --git a/arch/frv/include/asm/pgtable.h b/arch/frv/include/asm/pgtable.h index 93bcf2abd1a1..07d7a7ef8bd5 100644 --- a/arch/frv/include/asm/pgtable.h +++ b/arch/frv/include/asm/pgtable.h @@ -123,12 +123,14 @@ extern unsigned long empty_zero_page; #define PGDIR_MASK (~(PGDIR_SIZE - 1)) #define PTRS_PER_PGD 64 +#define __PAGETABLE_PUD_FOLDED #define PUD_SHIFT 26 #define PTRS_PER_PUD 1 #define PUD_SIZE (1UL << PUD_SHIFT) #define PUD_MASK (~(PUD_SIZE - 1)) #define PUE_SIZE 256 +#define __PAGETABLE_PMD_FOLDED #define PMD_SHIFT 26 #define PMD_SIZE (1UL << PMD_SHIFT) #define PMD_MASK (~(PMD_SIZE - 1)) -- 2.1.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/