The patch titled
mincore: do nested page table walks
has been added to the -mm tree. Its filename is
mincore-do-nested-page-table-walks.patch
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*** Remember to use Documentation/SubmitChecklist when testing your code ***
See http://userweb.kernel.org/~akpm/stuff/added-to-mm.txt to find
out what to do about this
The current -mm tree may be found at http://userweb.kernel.org/~akpm/mmotm/
------------------------------------------------------
Subject: mincore: do nested page table walks
From: Johannes Weiner <hannes@xxxxxxxxxxx>
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@xxxxxxxxxxx>
Cc: Andrea Arcangeli <aarcange@xxxxxxxxxx>
Cc: Naoya Horiguchi <n-horiguchi@xxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/mincore.c | 75 +++++++++++++++++++++++++++++++++++++------------
1 file changed, 58 insertions(+), 17 deletions(-)
diff -puN mm/mincore.c~mincore-do-nested-page-table-walks mm/mincore.c
--- a/mm/mincore.c~mincore-do-nested-page-table-walks
+++ a/mm/mincore.c
@@ -144,6 +144,60 @@ static void mincore_pte_range(struct vm_
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_
*/
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 add
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;
}
_
Patches currently in -mm which might be from hannes@xxxxxxxxxxx are
sparsemem-on-no-vmemmap-path-put-mem_map-on-node-high-too.patch
mincore-cleanups.patch
mincore-break-do_mincore-into-logical-pieces.patch
mincore-pass-ranges-as-startend-address-pairs.patch
mincore-do-nested-page-table-walks.patch
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