[PATCH 7/8] mm/khugepaged: clarify a comment regarding max_ptes_none check

[Nico Pache]

While reading collapse_scan_pmd, one may be confused on where the deferred
max_ptes_none check is done. Expand on this current comment by explaining
which function the max_ptes_none check is now done.

Suggested-by: David Hildenbrand <david@xxxxxxxxxx>
Signed-off-by: Nico Pache <npache@xxxxxxxxxx>
---
 mm/khugepaged.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/mm/khugepaged.c b/mm/khugepaged.c
index 3c6f1254deca..388045a524a3 100644
--- a/mm/khugepaged.c
+++ b/mm/khugepaged.c
@@ -1728,7 +1728,8 @@ static enum scan_result collapse_scan_pmd(struct mm_struct *mm,
 
 	/*
 	 * If PMD is the only enabled order, enforce max_ptes_none, otherwise
-	 * scan all pages to populate the bitmap for mTHP collapse.
+	 * scan all pages to populate the bitmap for mTHP collapse. The bitmap
+	 * is then checked again in mthp_collapse() for each attempted order.
 	 */
 	if (enabled_orders != BIT(HPAGE_PMD_ORDER))
 		ctx.max_ptes_none = KHUGEPAGED_MAX_PTES_LIMIT;
-- 
2.54.0