[PATCH mmotm 2/5] huge tmpfs: fix mlocked meminfo track huge unhuge mlocks fix

[Hugh Dickins]

Please add this fix after
huge-tmpfs-fix-mlocked-meminfo-track-huge-unhuge-mlocks.patch
for later merging into it.  I expect this to fix a build problem found
by robot on an x86_64 randconfig.  I was not able to reproduce the error,
but I'm growing to realize that different optimizers behave differently.

Reported-by: kbuild test robot <fengguang.wu@xxxxxxxxx>
Signed-off-by: Hugh Dickins <hughd@xxxxxxxxxx>
---
 mm/rmap.c |    6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

--- a/mm/rmap.c
+++ b/mm/rmap.c
@@ -1445,8 +1445,12 @@ static int try_to_unmap_one(struct page
 	 */
 	if (!(flags & TTU_IGNORE_MLOCK)) {
 		if (vma->vm_flags & VM_LOCKED) {
+			int nr_pages = 1;
+
+			if (IS_ENABLED(CONFIG_TRANSPARENT_HUGEPAGE) && !pte)
+				nr_pages = HPAGE_PMD_NR;
 			/* Holding pte lock, we do *not* need mmap_sem here */
-			mlock_vma_pages(page, pte ? 1 : HPAGE_PMD_NR);
+			mlock_vma_pages(page, nr_pages);
 			ret = SWAP_MLOCK;
 			goto out_unmap;
 		}