aboutsummaryrefslogtreecommitdiff
path: root/mm/mincore.c
diff options
context:
space:
mode:
authorJohannes Weiner <hannes@cmpxchg.org>2010-05-24 14:32:11 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2010-05-25 08:06:58 -0700
commite48293fd75b3aa67f43ad6e3d2ff397caa55d58b (patch)
tree8f163687833fb5e1fa84f72e2e72e1ab83aca91e /mm/mincore.c
parent25ef0e50cca790370ad7838e3ad74db6a6a2d829 (diff)
downloadlinux-e48293fd75b3aa67f43ad6e3d2ff397caa55d58b.tar.gz
mincore: do nested page table walks
Do page table walks with the well-known nested loops we use in several other places already. This avoids doing full page table walks after every pte range and also allows to handle unmapped areas bigger than one pte range in one go. Signed-off-by: Johannes Weiner <hannes@cmpxchg.org> Cc: Andrea Arcangeli <aarcange@redhat.com> Cc: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm/mincore.c')
-rw-r--r--mm/mincore.c75
1 files changed, 58 insertions, 17 deletions
diff --git a/mm/mincore.c b/mm/mincore.c
index 211604adc23..9ac42dc6d7b 100644
--- a/mm/mincore.c
+++ b/mm/mincore.c
@@ -144,6 +144,60 @@ static void mincore_pte_range(struct vm_area_struct *vma, pmd_t *pmd,
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_none_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);
+}
+
/*
* Do a chunk of "sys_mincore()". We've already checked
* all the arguments, we hold the mmap semaphore: we should
@@ -151,9 +205,6 @@ static void mincore_pte_range(struct vm_area_struct *vma, pmd_t *pmd,
*/
static long do_mincore(unsigned long addr, unsigned long pages, unsigned char *vec)
{
- pgd_t *pgd;
- pud_t *pud;
- pmd_t *pmd;
struct vm_area_struct *vma;
unsigned long end;
@@ -170,21 +221,11 @@ static long do_mincore(unsigned long addr, unsigned long pages, unsigned char *v
end = pmd_addr_end(addr, end);
- pgd = pgd_offset(vma->vm_mm, addr);
- if (pgd_none_or_clear_bad(pgd))
- goto none_mapped;
- pud = pud_offset(pgd, addr);
- if (pud_none_or_clear_bad(pud))
- goto none_mapped;
- pmd = pmd_offset(pud, addr);
- if (pmd_none_or_clear_bad(pmd))
- goto none_mapped;
-
- mincore_pte_range(vma, pmd, addr, end, vec);
- return (end - addr) >> PAGE_SHIFT;
+ if (is_vm_hugetlb_page(vma))
+ mincore_hugetlb_page_range(vma, addr, end, vec);
+ else
+ mincore_page_range(vma, addr, end, vec);
-none_mapped:
- mincore_unmapped_range(vma, addr, end, vec);
return (end - addr) >> PAGE_SHIFT;
}