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[210.143.35.52]) by mx.google.com with ESMTPS id ie20si952154igb.24.2014.11.06.23.05.45 for (version=TLSv1 cipher=RC4-SHA bits=128/128); Thu, 06 Nov 2014 23:05:45 -0800 (PST) From: Naoya Horiguchi Subject: [PATCH -mm v7 13/13] mincore: apply page table walker on do_mincore() Date: Fri, 7 Nov 2014 07:02:06 +0000 Message-ID: <1415343692-6314-14-git-send-email-n-horiguchi@ah.jp.nec.com> References: <1415343692-6314-1-git-send-email-n-horiguchi@ah.jp.nec.com> In-Reply-To: <1415343692-6314-1-git-send-email-n-horiguchi@ah.jp.nec.com> Content-Language: ja-JP Content-Type: text/plain; charset="iso-2022-jp" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Sender: owner-linux-mm@kvack.org List-ID: To: Andrew Morton Cc: Dave Hansen , Hugh Dickins , "Kirill A. Shutemov" , Peter Feiner , Jerome Marchand , "linux-mm@kvack.org" , "linux-kernel@vger.kernel.org" , Naoya Horiguchi This patch makes do_mincore() use walk_page_vma(), which reduces many lines of code by using common page table walk code. Signed-off-by: Naoya Horiguchi --- ChangeLog v5: - fix buffer overflow ChangeLog v4: - remove redundant vma 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 compi= ler warning --- mm/huge_memory.c | 20 ------- mm/mincore.c | 169 +++++++++++++++++++--------------------------------= ---- 2 files changed, 59 insertions(+), 130 deletions(-) diff --git mmotm-2014-11-05-16-01.orig/mm/huge_memory.c mmotm-2014-11-05-16= -01/mm/huge_memory.c index ff1ecea8c0d7..a81a0b917068 100644 --- mmotm-2014-11-05-16-01.orig/mm/huge_memory.c +++ mmotm-2014-11-05-16-01/mm/huge_memory.c @@ -1422,26 +1422,6 @@ int zap_huge_pmd(struct mmu_gather *tlb, struct vm_a= rea_struct *vma, return ret; } =20 -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 =3D 0; - - if (__pmd_trans_huge_lock(pmd, vma, &ptl) =3D=3D 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 =3D 1; - } - - return ret; -} - int move_huge_pmd(struct vm_area_struct *vma, struct vm_area_struct *new_v= ma, unsigned long old_addr, unsigned long new_addr, unsigned long old_end, diff --git mmotm-2014-11-05-16-01.orig/mm/mincore.c mmotm-2014-11-05-16-01/= mm/mincore.c index 725c80961048..0e548fbce19e 100644 --- mmotm-2014-11-05-16-01.orig/mm/mincore.c +++ mmotm-2014-11-05-16-01/mm/mincore.c @@ -19,38 +19,26 @@ #include #include =20 -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 =3D 0; #ifdef CONFIG_HUGETLB_PAGE - struct hstate *h; + unsigned char present; + unsigned char *vec =3D walk->private; =20 - h =3D 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 =3D huge_pte_offset(current->mm, - addr & huge_page_mask(h)); - present =3D ptep && !huge_pte_none(huge_ptep_get(ptep)); - while (1) { - *vec =3D present; - vec++; - addr +=3D PAGE_SIZE; - if (addr =3D=3D 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 =3D pte && !huge_pte_none(huge_ptep_get(pte)); + for (; addr !=3D end; vec++, addr +=3D PAGE_SIZE) + *vec =3D present; + walk->private =3D vec; #else BUG(); #endif + return err; } =20 /* @@ -94,14 +82,15 @@ static unsigned char mincore_page(struct address_space = *mapping, pgoff_t pgoff) return present; } =20 -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 =3D walk->vma; + unsigned char *vec =3D walk->private; unsigned long nr =3D (end - addr) >> PAGE_SHIFT; int i; =20 - if (vma->vm_file) { + if (vma && vma->vm_file) { pgoff_t pgoff; =20 pgoff =3D linear_page_index(vma, addr); @@ -111,25 +100,40 @@ static void mincore_unmapped_range(struct vm_area_str= uct *vma, for (i =3D 0; i < nr; i++) vec[i] =3D 0; } + walk->private +=3D nr; + return 0; } =20 -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 =3D walk->vma; pte_t *ptep; =20 - ptep =3D pte_offset_map_lock(vma->vm_mm, pmd, addr, &ptl); - do { + if (pmd_trans_huge_lock(pmd, vma, &ptl) =3D=3D 1) { + memset(walk->private, 1, (end - addr) >> PAGE_SHIFT); + walk->private +=3D (end - addr) >> PAGE_SHIFT; + spin_unlock(ptl); + return 0; + } + + if (pmd_trans_unstable(pmd)) { + mincore_unmapped_range(addr, end, walk); + return 0; + } + + ptep =3D pte_offset_map_lock(walk->mm, pmd, addr, &ptl); + for (; addr !=3D end; ptep++, addr +=3D PAGE_SIZE) { pte_t pte =3D *ptep; pgoff_t pgoff; + unsigned char *vec =3D walk->private; =20 - next =3D 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 =3D 1; else if (pte_file(pte)) { pgoff =3D pte_to_pgoff(pte); @@ -151,70 +155,11 @@ static void mincore_pte_range(struct vm_area_struct *= vma, pmd_t *pmd, #endif } } - vec++; - } while (ptep++, addr =3D next, addr !=3D 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 =3D pmd_offset(pud, addr); - do { - next =3D pmd_addr_end(addr, end); - if (pmd_trans_huge(*pmd)) { - if (mincore_huge_pmd(vma, pmd, addr, next, vec)) { - vec +=3D (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 +=3D (next - addr) >> PAGE_SHIFT; - } while (pmd++, addr =3D next, addr !=3D 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 =3D pud_offset(pgd, addr); - do { - next =3D 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 +=3D (next - addr) >> PAGE_SHIFT; - } while (pud++, addr =3D next, addr !=3D 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 =3D pgd_offset(vma->vm_mm, addr); - do { - next =3D 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 +=3D (next - addr) >> PAGE_SHIFT; - } while (pgd++, addr =3D next, addr !=3D end); + cond_resched(); + return 0; } =20 /* @@ -226,18 +171,22 @@ static long do_mincore(unsigned long addr, unsigned l= ong pages, unsigned char *v { struct vm_area_struct *vma; unsigned long end; + int err; + struct mm_walk mincore_walk =3D { + .pmd_entry =3D mincore_pte_range, + .pte_hole =3D mincore_unmapped_range, + .hugetlb_entry =3D mincore_hugetlb, + .private =3D vec, + }; =20 vma =3D find_vma(current->mm, addr); if (!vma || addr < vma->vm_start) return -ENOMEM; - + mincore_walk.mm =3D vma->vm_mm; end =3D 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 =3D walk_page_range(addr, end, &mincore_walk); + if (err < 0) + return err; return (end - addr) >> PAGE_SHIFT; } =20 --=20 2.2.0.rc0.2.gf745acb -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. 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