mm/khugepaged: introduce release_pte_folio() to replace release_pte_page()

release_pte_page() is converted to be a wrapper for release_pte_folio() to
help facilitate the khugepaged conversion to folios.

This replaces 3 calls to compound_head() with 1, and saves 85 bytes of
kernel text.

Link: https://lkml.kernel.org/r/20230114001556.43795-1-vishal.moola@gmail.comSigned-off-by: Vishal Moola (Oracle) <vishal.moola@gmail.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mm/khugepaged.c

@@ -490,13 +490,18 @@ void __khugepaged_exit(struct mm_struct *mm)
 	}
 }
 
+static void release_pte_folio(struct folio *folio)
+{
+	node_stat_mod_folio(folio,
+			NR_ISOLATED_ANON + folio_is_file_lru(folio),
+			-folio_nr_pages(folio));
+	folio_unlock(folio);
+	folio_putback_lru(folio);
+}
+
 static void release_pte_page(struct page *page)
 {
-	mod_node_page_state(page_pgdat(page),
-			NR_ISOLATED_ANON + page_is_file_lru(page),
-			-compound_nr(page));
-	unlock_page(page);
-	putback_lru_page(page);
+	release_pte_folio(page_folio(page));
 }
 
 static void release_pte_pages(pte_t *pte, pte_t *_pte,