mm/apply_to_range: call pte function with lazy updates

Make the pte-level function in apply_to_range be called in lazy mmu mode,
so that any pagetable modifications can be batched.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Nick Piggin <nickpiggin@yahoo.com.au>
Cc: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Cc: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 4 insertions, 0 deletions

diff --git a/mm/memory.c b/mm/memory.c
index 99e8d5c7b312..b5af358b8b22 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -1645,6 +1645,8 @@ static int apply_to_pte_range(struct mm_struct *mm, pmd_t *pmd,
 
         BUG_ON(pmd_huge(*pmd));
 
+        arch_enter_lazy_mmu_mode();
+
         token = pmd_pgtable(*pmd);
 
         do {
@@ -1653,6 +1655,8 @@ static int apply_to_pte_range(struct mm_struct *mm, pmd_t *pmd,
                         break;
         } while (pte++, addr += PAGE_SIZE, addr != end);
 
+        arch_leave_lazy_mmu_mode();
+
         if (mm != &init_mm)
                 pte_unmap_unlock(pte-1, ptl);
         return err;