Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933924AbaFIQGb (ORCPT ); Mon, 9 Jun 2014 12:06:31 -0400 Received: from mga03.intel.com ([143.182.124.21]:41697 "EHLO mga03.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933634AbaFIQEh (ORCPT ); Mon, 9 Jun 2014 12:04:37 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.98,1003,1392192000"; d="scan'208";a="443394996" From: "Kirill A. Shutemov" To: Andrew Morton , Andrea Arcangeli Cc: Dave Hansen , Hugh Dickins , Mel Gorman , Rik van Riel , Vlastimil Babka , linux-kernel@vger.kernel.org, linux-mm@kvack.org, "Kirill A. Shutemov" Subject: [PATCH, RFC 08/10] x86, thp: remove remove infrastructure for handling splitting PMDs Date: Mon, 9 Jun 2014 19:04:19 +0300 Message-Id: <1402329861-7037-9-git-send-email-kirill.shutemov@linux.intel.com> X-Mailer: git-send-email 2.0.0.rc4 In-Reply-To: <1402329861-7037-1-git-send-email-kirill.shutemov@linux.intel.com> References: <1402329861-7037-1-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 With new refcounting we don't need to mark PMDs splitting. Let's drop code to handle this. Signed-off-by: Kirill A. Shutemov --- arch/x86/include/asm/pgtable.h | 9 --------- arch/x86/include/asm/pgtable_types.h | 2 -- arch/x86/mm/gup.c | 13 +------------ arch/x86/mm/pgtable.c | 14 -------------- 4 files changed, 1 insertion(+), 37 deletions(-) diff --git a/arch/x86/include/asm/pgtable.h b/arch/x86/include/asm/pgtable.h index 0ec056012618..1c60bfca6b65 100644 --- a/arch/x86/include/asm/pgtable.h +++ b/arch/x86/include/asm/pgtable.h @@ -158,11 +158,6 @@ static inline int pmd_large(pmd_t pte) } #ifdef CONFIG_TRANSPARENT_HUGEPAGE -static inline int pmd_trans_splitting(pmd_t pmd) -{ - return pmd_val(pmd) & _PAGE_SPLITTING; -} - static inline int pmd_trans_huge(pmd_t pmd) { return pmd_val(pmd) & _PAGE_PSE; @@ -799,10 +794,6 @@ extern int pmdp_clear_flush_young(struct vm_area_struct *vma, unsigned long address, pmd_t *pmdp); -#define __HAVE_ARCH_PMDP_SPLITTING_FLUSH -extern void pmdp_splitting_flush(struct vm_area_struct *vma, - unsigned long addr, pmd_t *pmdp); - #define __HAVE_ARCH_PMD_WRITE static inline int pmd_write(pmd_t pmd) { diff --git a/arch/x86/include/asm/pgtable_types.h b/arch/x86/include/asm/pgtable_types.h index f216963760e5..7d8066d1d9c0 100644 --- a/arch/x86/include/asm/pgtable_types.h +++ b/arch/x86/include/asm/pgtable_types.h @@ -22,7 +22,6 @@ #define _PAGE_BIT_PAT_LARGE 12 /* On 2MB or 1GB pages */ #define _PAGE_BIT_SPECIAL _PAGE_BIT_SOFTW1 #define _PAGE_BIT_CPA_TEST _PAGE_BIT_SOFTW1 -#define _PAGE_BIT_SPLITTING _PAGE_BIT_SOFTW2 /* only valid on a PSE pmd */ #define _PAGE_BIT_IOMAP _PAGE_BIT_SOFTW2 /* flag used to indicate IO mapping */ #define _PAGE_BIT_HIDDEN _PAGE_BIT_SOFTW3 /* hidden by kmemcheck */ #define _PAGE_BIT_SOFT_DIRTY _PAGE_BIT_SOFTW3 /* software dirty tracking */ @@ -57,7 +56,6 @@ #define _PAGE_PAT_LARGE (_AT(pteval_t, 1) << _PAGE_BIT_PAT_LARGE) #define _PAGE_SPECIAL (_AT(pteval_t, 1) << _PAGE_BIT_SPECIAL) #define _PAGE_CPA_TEST (_AT(pteval_t, 1) << _PAGE_BIT_CPA_TEST) -#define _PAGE_SPLITTING (_AT(pteval_t, 1) << _PAGE_BIT_SPLITTING) #define __HAVE_ARCH_PTE_SPECIAL #ifdef CONFIG_KMEMCHECK diff --git a/arch/x86/mm/gup.c b/arch/x86/mm/gup.c index 754bca23ec1b..b65b3fc4494a 100644 --- a/arch/x86/mm/gup.c +++ b/arch/x86/mm/gup.c @@ -157,18 +157,7 @@ static int gup_pmd_range(pud_t pud, unsigned long addr, unsigned long end, pmd_t pmd = *pmdp; next = pmd_addr_end(addr, end); - /* - * The pmd_trans_splitting() check below explains why - * pmdp_splitting_flush has to flush the tlb, to stop - * this gup-fast code from running while we set the - * splitting bit in the pmd. Returning zero will take - * the slow path that will call wait_split_huge_page() - * if the pmd is still in splitting state. gup-fast - * can't because it has irq disabled and - * wait_split_huge_page() would never return as the - * tlb flush IPI wouldn't run. - */ - if (pmd_none(pmd) || pmd_trans_splitting(pmd)) + if (pmd_none(pmd)) return 0; if (unlikely(pmd_large(pmd))) { /* diff --git a/arch/x86/mm/pgtable.c b/arch/x86/mm/pgtable.c index 6fb6927f9e76..336847f5719e 100644 --- a/arch/x86/mm/pgtable.c +++ b/arch/x86/mm/pgtable.c @@ -429,20 +429,6 @@ int pmdp_clear_flush_young(struct vm_area_struct *vma, return young; } - -void pmdp_splitting_flush(struct vm_area_struct *vma, - unsigned long address, pmd_t *pmdp) -{ - int set; - VM_BUG_ON(address & ~HPAGE_PMD_MASK); - set = !test_and_set_bit(_PAGE_BIT_SPLITTING, - (unsigned long *)pmdp); - if (set) { - pmd_update(vma->vm_mm, address, pmdp); - /* need tlb flush only to serialize against gup-fast */ - flush_tlb_range(vma, address, address + HPAGE_PMD_SIZE); - } -} #endif /** -- 2.0.0.rc4 -- 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/