From: Rik van Riel <riel@redhat.com>
Date: Mon, 7 Apr 2014 22:36:55 +0000 (-0700)
Subject: mm,numa: reorganize change_pmd_range()
X-Git-Tag: firefly_0821_release~176^2~4111^2~153
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=88a9ab6e3dfb5b10168130c255c6102c925343ab;p=firefly-linux-kernel-4.4.55.git

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>
---

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;