From patchwork Wed May 26 06:38:49 2010 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: David Miller X-Patchwork-Id: 53589 X-Patchwork-Delegate: davem@davemloft.net Return-Path: X-Original-To: patchwork-incoming@ozlabs.org Delivered-To: patchwork-incoming@ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 747BBB7D16 for ; Wed, 26 May 2010 16:38:41 +1000 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752711Ab0EZGik (ORCPT ); Wed, 26 May 2010 02:38:40 -0400 Received: from 74-93-104-97-Washington.hfc.comcastbusiness.net ([74.93.104.97]:35067 "EHLO sunset.davemloft.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752574Ab0EZGij convert rfc822-to-8bit (ORCPT ); Wed, 26 May 2010 02:38:39 -0400 Received: from localhost (localhost [127.0.0.1]) by sunset.davemloft.net (Postfix) with ESMTP id A412B24C08E; Tue, 25 May 2010 23:38:49 -0700 (PDT) Date: Tue, 25 May 2010 23:38:49 -0700 (PDT) Message-Id: <20100525.233849.104052594.davem@davemloft.net> To: tkhai@yandex.ru Cc: sparclinux@vger.kernel.org Subject: Re: [PATCH]sparc32: Fix impossibility of swap disabling after intensive swap using From: David Miller In-Reply-To: <80141272607039@web66.yandex.ru> References: <41981272583715@web15.yandex.ru> <20100429.165815.235700454.davem@davemloft.net> <80141272607039@web66.yandex.ru> X-Mailer: Mew version 6.3 on Emacs 23.1 / Mule 6.0 (HANACHIRUSATO) Mime-Version: 1.0 Sender: sparclinux-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: sparclinux@vger.kernel.org From: Тхай Кирилл Date: Fri, 30 Apr 2010 09:57:19 +0400 > I can mistake, but it seems to me, that pte_none is more wide check, > than belonging pte to mmu device. Not exactly. pte_none() should be true if the PTE encodes nothing, not a swap entry, not a MMU PTE, nothing at all. > In other case none_mask must be something like 0xF0000004, because > hardware ignores ptes with zeroed lower two bits. It seems that the correct thing to do is to kill this none_mask thing entirely. Could you try this patch instead of your's? Thanks! --- sparc32: Kill none_mask, it's bogus. For some reason, the pte_none() calculation for srmmu sparc32 chips was masking out the top 4 bits. That doesn't make any sense, as those are just some of the physical bits of the PTE encoding. Furthermore, this mistake breaks things when the offset of of a swap entry has a large enough offset as reported by Тхай Кирилл. Sun4c always set it to zero, so it's really completely useless, kill it. Reported-by: Тхай Кирилл Signed-off-by: David S. Miller --- arch/sparc/include/asm/pgtable_32.h | 5 ++--- arch/sparc/mm/srmmu.c | 2 -- arch/sparc/mm/sun4c.c | 3 --- 3 files changed, 2 insertions(+), 8 deletions(-) diff --git a/arch/sparc/include/asm/pgtable_32.h b/arch/sparc/include/asm/pgtable_32.h index 77f906d..0ece77f 100644 --- a/arch/sparc/include/asm/pgtable_32.h +++ b/arch/sparc/include/asm/pgtable_32.h @@ -142,13 +142,12 @@ BTFIXUPDEF_CALL_CONST(unsigned long, pgd_page_vaddr, pgd_t) #define pmd_page(pmd) BTFIXUP_CALL(pmd_page)(pmd) #define pgd_page_vaddr(pgd) BTFIXUP_CALL(pgd_page_vaddr)(pgd) -BTFIXUPDEF_SETHI(none_mask) BTFIXUPDEF_CALL_CONST(int, pte_present, pte_t) BTFIXUPDEF_CALL(void, pte_clear, pte_t *) static inline int pte_none(pte_t pte) { - return !(pte_val(pte) & ~BTFIXUP_SETHI(none_mask)); + return !pte_val(pte); } #define pte_present(pte) BTFIXUP_CALL(pte_present)(pte) @@ -160,7 +159,7 @@ BTFIXUPDEF_CALL(void, pmd_clear, pmd_t *) static inline int pmd_none(pmd_t pmd) { - return !(pmd_val(pmd) & ~BTFIXUP_SETHI(none_mask)); + return !pmd_val(pmd); } #define pmd_bad(pmd) BTFIXUP_CALL(pmd_bad)(pmd) diff --git a/arch/sparc/mm/srmmu.c b/arch/sparc/mm/srmmu.c index f5f75a5..b0b43aa 100644 --- a/arch/sparc/mm/srmmu.c +++ b/arch/sparc/mm/srmmu.c @@ -2215,8 +2215,6 @@ void __init ld_mmu_srmmu(void) BTFIXUPSET_CALL(pmd_page, srmmu_pmd_page, BTFIXUPCALL_NORM); BTFIXUPSET_CALL(pgd_page_vaddr, srmmu_pgd_page, BTFIXUPCALL_NORM); - BTFIXUPSET_SETHI(none_mask, 0xF0000000); - BTFIXUPSET_CALL(pte_present, srmmu_pte_present, BTFIXUPCALL_NORM); BTFIXUPSET_CALL(pte_clear, srmmu_pte_clear, BTFIXUPCALL_SWAPO0G0); diff --git a/arch/sparc/mm/sun4c.c b/arch/sparc/mm/sun4c.c index cf38846..4289f90 100644 --- a/arch/sparc/mm/sun4c.c +++ b/arch/sparc/mm/sun4c.c @@ -2087,9 +2087,6 @@ void __init ld_mmu_sun4c(void) BTFIXUPSET_CALL(set_pte, sun4c_set_pte, BTFIXUPCALL_STO1O0); - /* The 2.4.18 code does not set this on sun4c, how does it work? XXX */ - /* BTFIXUPSET_SETHI(none_mask, 0x00000000); */ /* Defaults to zero? */ - BTFIXUPSET_CALL(pte_pfn, sun4c_pte_pfn, BTFIXUPCALL_NORM); #if 0 /* PAGE_SHIFT <= 12 */ /* Eek. Investigate. XXX */ BTFIXUPSET_CALL(pmd_page, sun4c_pmd_page, BTFIXUPCALL_ANDNINT(PAGE_SIZE - 1));