mm,numa: reorganize change_pmd_range()

Reorganize the order of ifs in change_pmd_range a little, in preparation
for the next patch.

[akpm@linux-foundation.org: fix indenting, per David]
Signed-off-by: Rik van Riel <riel@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Reported-by: Xing Gang <gang.xing@hp.com>
Tested-by: Chegu Vinod <chegu_vinod@hp.com>
Acked-by: David Rientjes <rientjes@google.com>
Cc: Sasha Levin <sasha.levin@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 4 insertions, 3 deletions

diff --git a/mm/mprotect.c b/mm/mprotect.c
index 769a67a15803..79cb51866e02 100644
--- a/mm/mprotect.c
+++ b/mm/mprotect.c
@@ -118,6 +118,8 @@ static inline unsigned long change_pmd_range(struct vm_area_struct *vma,
                 unsigned long this_pages;
 
                 next = pmd_addr_end(addr, end);
+                if (!pmd_trans_huge(*pmd) && pmd_none_or_clear_bad(pmd))
+                        continue;
                 if (pmd_trans_huge(*pmd)) {
                         if (next - addr != HPAGE_PMD_SIZE)
                                 split_huge_page_pmd(vma, addr, pmd);
@@ -133,10 +135,9 @@ static inline unsigned long change_pmd_range(struct vm_area_struct *vma,
                                         continue;
                                 }
                         }
-                        /* fall through */
+                        /* fall through, the trans huge pmd just split */
                 }
-                if (pmd_none_or_clear_bad(pmd))
-                        continue;
+                VM_BUG_ON(pmd_trans_huge(*pmd));
                 this_pages = change_pte_range(vma, pmd, addr, next, newprot,
                                  dirty_accountable, prot_numa);
                 pages += this_pages;