Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757678AbaFTUN6 (ORCPT ); Fri, 20 Jun 2014 16:13:58 -0400 Received: from mx1.redhat.com ([209.132.183.28]:42484 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S965334AbaFTUMO (ORCPT ); Fri, 20 Jun 2014 16:12:14 -0400 From: Naoya Horiguchi To: linux-mm@kvack.org Cc: Andrew Morton , Dave Hansen , Hugh Dickins , "Kirill A. Shutemov" , linux-kernel@vger.kernel.org, Naoya Horiguchi Subject: [PATCH v3 13/13] mincore: apply page table walker on do_mincore() Date: Fri, 20 Jun 2014 16:11:39 -0400 Message-Id: <1403295099-6407-14-git-send-email-n-horiguchi@ah.jp.nec.com> In-Reply-To: <1403295099-6407-1-git-send-email-n-horiguchi@ah.jp.nec.com> References: <1403295099-6407-1-git-send-email-n-horiguchi@ah.jp.nec.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This patch makes do_mincore() use walk_page_vma(), which reduces many lines of code by using common page table walk code. ChangeLog v3: - add NULL vma check in mincore_unmapped_range() - don't use pte_entry() ChangeLog v2: - change type of args of callbacks to void * - move definition of mincore_walk to the start of the function to fix compiler warning Signed-off-by: Naoya Horiguchi --- mm/huge_memory.c | 20 ------- mm/mincore.c | 174 ++++++++++++++++++++----------------------------------- 2 files changed, 63 insertions(+), 131 deletions(-) diff --git v3.16-rc1.orig/mm/huge_memory.c v3.16-rc1/mm/huge_memory.c index c5ff461e0253..53f451969931 100644 --- v3.16-rc1.orig/mm/huge_memory.c +++ v3.16-rc1/mm/huge_memory.c @@ -1379,26 +1379,6 @@ int zap_huge_pmd(struct mmu_gather *tlb, struct vm_area_struct *vma, return ret; } -int mincore_huge_pmd(struct vm_area_struct *vma, pmd_t *pmd, - unsigned long addr, unsigned long end, - unsigned char *vec) -{ - spinlock_t *ptl; - int ret = 0; - - if (__pmd_trans_huge_lock(pmd, vma, &ptl) == 1) { - /* - * All logical pages in the range are present - * if backed by a huge page. - */ - spin_unlock(ptl); - memset(vec, 1, (end - addr) >> PAGE_SHIFT); - ret = 1; - } - - return ret; -} - int move_huge_pmd(struct vm_area_struct *vma, struct vm_area_struct *new_vma, unsigned long old_addr, unsigned long new_addr, unsigned long old_end, diff --git v3.16-rc1.orig/mm/mincore.c v3.16-rc1/mm/mincore.c index 725c80961048..964bafed6320 100644 --- v3.16-rc1.orig/mm/mincore.c +++ v3.16-rc1/mm/mincore.c @@ -19,38 +19,26 @@ #include #include -static void mincore_hugetlb_page_range(struct vm_area_struct *vma, - unsigned long addr, unsigned long end, - unsigned char *vec) +static int mincore_hugetlb(pte_t *pte, unsigned long hmask, unsigned long addr, + unsigned long end, struct mm_walk *walk) { + int err = 0; #ifdef CONFIG_HUGETLB_PAGE - struct hstate *h; + unsigned char present; + unsigned char *vec = walk->private; - h = hstate_vma(vma); - while (1) { - unsigned char present; - pte_t *ptep; - /* - * Huge pages are always in RAM for now, but - * theoretically it needs to be checked. - */ - ptep = huge_pte_offset(current->mm, - addr & huge_page_mask(h)); - present = ptep && !huge_pte_none(huge_ptep_get(ptep)); - while (1) { - *vec = present; - vec++; - addr += PAGE_SIZE; - if (addr == end) - return; - /* check hugepage border */ - if (!(addr & ~huge_page_mask(h))) - break; - } - } + /* + * Hugepages under user process are always in RAM and never + * swapped out, but theoretically it needs to be checked. + */ + present = pte && !huge_pte_none(huge_ptep_get(pte)); + for (; addr != end; vec++, addr += PAGE_SIZE) + *vec = present; + walk->private += (end - addr) >> PAGE_SHIFT; #else BUG(); #endif + return err; } /* @@ -94,14 +82,15 @@ static unsigned char mincore_page(struct address_space *mapping, pgoff_t pgoff) return present; } -static void mincore_unmapped_range(struct vm_area_struct *vma, - unsigned long addr, unsigned long end, - unsigned char *vec) +static int mincore_unmapped_range(unsigned long addr, unsigned long end, + struct mm_walk *walk) { + struct vm_area_struct *vma = walk->vma; + unsigned char *vec = walk->private; unsigned long nr = (end - addr) >> PAGE_SHIFT; int i; - if (vma->vm_file) { + if (vma && vma->vm_file) { pgoff_t pgoff; pgoff = linear_page_index(vma, addr); @@ -111,25 +100,38 @@ static void mincore_unmapped_range(struct vm_area_struct *vma, for (i = 0; i < nr; i++) vec[i] = 0; } + walk->private += nr; + return 0; } -static void mincore_pte_range(struct vm_area_struct *vma, pmd_t *pmd, - unsigned long addr, unsigned long end, - unsigned char *vec) +static int mincore_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end, + struct mm_walk *walk) { - unsigned long next; spinlock_t *ptl; + struct vm_area_struct *vma = walk->vma; pte_t *ptep; - ptep = pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl); - do { + if (pmd_trans_huge_lock(pmd, vma, &ptl) == 1) { + memset(walk->private, 1, (end - addr) >> PAGE_SHIFT); + walk->private += (end - addr) >> PAGE_SHIFT; + spin_unlock(ptl); + return 0; + } + + if (pmd_trans_unstable(pmd)) + return 0; + + ptep = pte_offset_map_lock(walk->mm, pmd, addr, &ptl); + for (; addr != end; ptep++, addr += PAGE_SIZE) { pte_t pte = *ptep; pgoff_t pgoff; + unsigned char *vec = walk->private; - next = addr + PAGE_SIZE; - if (pte_none(pte)) - mincore_unmapped_range(vma, addr, next, vec); - else if (pte_present(pte)) + if (pte_none(pte)) { + mincore_unmapped_range(addr, addr + PAGE_SIZE, walk); + continue; + } + if (pte_present(pte)) *vec = 1; else if (pte_file(pte)) { pgoff = pte_to_pgoff(pte); @@ -151,70 +153,11 @@ static void mincore_pte_range(struct vm_area_struct *vma, pmd_t *pmd, #endif } } - vec++; - } while (ptep++, addr = next, addr != end); + walk->private++; + } pte_unmap_unlock(ptep - 1, ptl); -} - -static void mincore_pmd_range(struct vm_area_struct *vma, pud_t *pud, - unsigned long addr, unsigned long end, - unsigned char *vec) -{ - unsigned long next; - pmd_t *pmd; - - pmd = pmd_offset(pud, addr); - do { - next = pmd_addr_end(addr, end); - if (pmd_trans_huge(*pmd)) { - if (mincore_huge_pmd(vma, pmd, addr, next, vec)) { - vec += (next - addr) >> PAGE_SHIFT; - continue; - } - /* fall through */ - } - if (pmd_none_or_trans_huge_or_clear_bad(pmd)) - mincore_unmapped_range(vma, addr, next, vec); - else - mincore_pte_range(vma, pmd, addr, next, vec); - vec += (next - addr) >> PAGE_SHIFT; - } while (pmd++, addr = next, addr != end); -} - -static void mincore_pud_range(struct vm_area_struct *vma, pgd_t *pgd, - unsigned long addr, unsigned long end, - unsigned char *vec) -{ - unsigned long next; - pud_t *pud; - - pud = pud_offset(pgd, addr); - do { - next = pud_addr_end(addr, end); - if (pud_none_or_clear_bad(pud)) - mincore_unmapped_range(vma, addr, next, vec); - else - mincore_pmd_range(vma, pud, addr, next, vec); - vec += (next - addr) >> PAGE_SHIFT; - } while (pud++, addr = next, addr != end); -} - -static void mincore_page_range(struct vm_area_struct *vma, - unsigned long addr, unsigned long end, - unsigned char *vec) -{ - unsigned long next; - pgd_t *pgd; - - pgd = pgd_offset(vma->vm_mm, addr); - do { - next = pgd_addr_end(addr, end); - if (pgd_none_or_clear_bad(pgd)) - mincore_unmapped_range(vma, addr, next, vec); - else - mincore_pud_range(vma, pgd, addr, next, vec); - vec += (next - addr) >> PAGE_SHIFT; - } while (pgd++, addr = next, addr != end); + cond_resched(); + return 0; } /* @@ -225,20 +168,29 @@ static void mincore_page_range(struct vm_area_struct *vma, static long do_mincore(unsigned long addr, unsigned long pages, unsigned char *vec) { struct vm_area_struct *vma; - unsigned long end; + int err; + struct mm_walk mincore_walk = { + .pmd_entry = mincore_pte_range, + .pte_hole = mincore_unmapped_range, + .hugetlb_entry = mincore_hugetlb, + .private = vec, + }; vma = find_vma(current->mm, addr); if (!vma || addr < vma->vm_start) return -ENOMEM; + mincore_walk.mm = vma->vm_mm; + mincore_walk.vma = vma; - end = min(vma->vm_end, addr + (pages << PAGE_SHIFT)); - - if (is_vm_hugetlb_page(vma)) - mincore_hugetlb_page_range(vma, addr, end, vec); - else - mincore_page_range(vma, addr, end, vec); + err = walk_page_vma(vma, &mincore_walk); + if (err < 0) + return err; + else { + unsigned long end; - return (end - addr) >> PAGE_SHIFT; + end = min(vma->vm_end, addr + (pages << PAGE_SHIFT)); + return (end - addr) >> PAGE_SHIFT; + } } /* -- 1.9.3 -- 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/