mm/filemap.c: add comment for confusing logic in page_cache_tree_inse…

…rt() Unlike THP, hugetlb pages are represented by one entry in the radix-tree. [[email protected]: tweak comment] Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Kirill A. Shutemov <[email protected]> Acked-by: Johannes Weiner <[email protected]> Cc: Jan Kara <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
josf · Dec 13, 2016 · c70b647 · c70b647
1 parent d5e6eff
commit c70b647
Showing 1 changed file with 4 additions and 1 deletion.
diff --git a/mm/filemap.c b/mm/filemap.c
@@ -169,7 +169,10 @@ static int page_cache_tree_insert(struct address_space *mapping,
 static void page_cache_tree_delete(struct address_space *mapping,
 				   struct page *page, void *shadow)
 {
-	int i, nr = PageHuge(page) ? 1 : hpage_nr_pages(page);
+	int i, nr;
+
+	/* hugetlb pages are represented by one entry in the radix tree */
+	nr = PageHuge(page) ? 1 : hpage_nr_pages(page);
 
 	VM_BUG_ON_PAGE(!PageLocked(page), page);
 	VM_BUG_ON_PAGE(PageTail(page), page);