From: Matthew Wilcox (Oracle) <willy@infradead.org>
Date: Fri, 7 Jan 2022 18:03:48 +0000 (-0500)
Subject: filemap: Use folio_put_refs() in filemap_free_folio()
X-Git-Tag: baikal/mips/sdk6.1~6569^2
X-Git-Url: https://git.baikalelectronics.ru/sdk/?a=commitdiff_plain;h=e31661ac935d05f63ceaa0a0adef6ac2f6d93adf;p=kernel.git

filemap: Use folio_put_refs() in filemap_free_folio()

This shrinks filemap_free_folio() by 55 bytes in my .config; 24 bytes
from removing the VM_BUG_ON_FOLIO() and 31 bytes from unifying the
small/large folio paths.

We could just use folio_ref_sub() here since the caller should hold a
reference (as the VM_BUG_ON_FOLIO() was asserting), but that's fragile.

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
---

diff --git a/mm/filemap.c b/mm/filemap.c
index 2fd9b2f24025f..afc8f5ca85ac2 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -231,17 +231,15 @@ void __filemap_remove_folio(struct folio *folio, void *shadow)
 void filemap_free_folio(struct address_space *mapping, struct folio *folio)
 {
 	void (*freepage)(struct page *);
+	int refs = 1;
 
 	freepage = mapping->a_ops->freepage;
 	if (freepage)
 		freepage(&folio->page);
 
-	if (folio_test_large(folio) && !folio_test_hugetlb(folio)) {
-		folio_ref_sub(folio, folio_nr_pages(folio));
-		VM_BUG_ON_FOLIO(folio_ref_count(folio) <= 0, folio);
-	} else {
-		folio_put(folio);
-	}
+	if (folio_test_large(folio) && !folio_test_hugetlb(folio))
+		refs = folio_nr_pages(folio);
+	folio_put_refs(folio, refs);
 }
 
 /**