[PATCH v4 23/25] mm/page-writeback: Convert test_clear_page_writeback to take a folio

["Matthew Wilcox (Oracle)" <willy@infradead.org>]

The one caller of test_clear_page_writeback() already has a folio,
so rename it to test_clear_folio_writeback() to make it clear that it
operates on the entire folio.  This removes a few calls to compound_head()
but actually grows the function by 49 bytes because it now accounts for
the number of pages in the folio.

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
---
 include/linux/page-flags.h |  2 +-
 mm/filemap.c               |  2 +-
 mm/page-writeback.c        | 20 ++++++++++----------
 3 files changed, 12 insertions(+), 12 deletions(-)

diff --git a/include/linux/page-flags.h b/include/linux/page-flags.h
index 90381858d901..01aa4a71bf14 100644
--- a/include/linux/page-flags.h
+++ b/include/linux/page-flags.h
@@ -594,7 +594,7 @@ static __always_inline void SetPageUptodate(struct page *page)
 
 CLEARPAGEFLAG(Uptodate, uptodate, PF_NO_TAIL)
 
-int test_clear_page_writeback(struct page *page);
+int test_clear_folio_writeback(struct folio *folio);
 int __test_set_page_writeback(struct page *page, bool keep_write);
 
 #define test_set_page_writeback(page)			\
diff --git a/mm/filemap.c b/mm/filemap.c
index e91fa14c86c7..57f46ff2f230 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -1446,7 +1446,7 @@ void end_folio_writeback(struct folio *folio)
 	 * reused before the wake_up_folio().
 	 */
 	get_folio(folio);
-	if (!test_clear_page_writeback(&folio->page))
+	if (!test_clear_folio_writeback(folio))
 		BUG();
 
 	smp_mb__after_atomic();
diff --git a/mm/page-writeback.c b/mm/page-writeback.c
index 6c1b4737c383..fa3411ea4cd3 100644
--- a/mm/page-writeback.c
+++ b/mm/page-writeback.c
@@ -589,7 +589,7 @@ static void wb_domain_writeout_inc(struct wb_domain *dom,
 
 /*
  * Increment @wb's writeout completion count and the global writeout
- * completion count. Called from test_clear_page_writeback().
+ * completion count. Called from test_clear_folio_writeback().
  */
 static inline void __wb_writeout_inc(struct bdi_writeback *wb)
 {
@@ -2719,24 +2719,24 @@ int clear_page_dirty_for_io(struct page *page)
 }
 EXPORT_SYMBOL(clear_page_dirty_for_io);
 
-int test_clear_page_writeback(struct page *page)
+int test_clear_folio_writeback(struct folio *folio)
 {
-	struct address_space *mapping = page_mapping(page);
+	struct address_space *mapping = folio_mapping(folio);
 	struct mem_cgroup *memcg;
 	struct lruvec *lruvec;
 	int ret;
 
-	memcg = lock_page_memcg(page);
-	lruvec = mem_cgroup_page_lruvec(page, page_pgdat(page));
+	memcg = lock_folio_memcg(folio);
+	lruvec = mem_cgroup_folio_lruvec(folio, folio_pgdat(folio));
 	if (mapping && mapping_use_writeback_tags(mapping)) {
 		struct inode *inode = mapping->host;
 		struct backing_dev_info *bdi = inode_to_bdi(inode);
 		unsigned long flags;
 
 		xa_lock_irqsave(&mapping->i_pages, flags);
-		ret = TestClearPageWriteback(page);
+		ret = TestClearFolioWriteback(folio);
 		if (ret) {
-			__xa_clear_mark(&mapping->i_pages, page_index(page),
+			__xa_clear_mark(&mapping->i_pages, folio_index(folio),
 						PAGECACHE_TAG_WRITEBACK);
 			if (bdi->capabilities & BDI_CAP_WRITEBACK_ACCT) {
 				struct bdi_writeback *wb = inode_to_wb(inode);
@@ -2752,12 +2752,12 @@ int test_clear_page_writeback(struct page *page)
 
 		xa_unlock_irqrestore(&mapping->i_pages, flags);
 	} else {
-		ret = TestClearPageWriteback(page);
+		ret = TestClearFolioWriteback(folio);
 	}
 	if (ret) {
 		dec_lruvec_state(lruvec, NR_WRITEBACK);
-		dec_zone_page_state(page, NR_ZONE_WRITE_PENDING);
-		inc_node_page_state(page, NR_WRITTEN);
+		dec_zone_folio_stat(folio, NR_ZONE_WRITE_PENDING);
+		inc_node_folio_stat(folio, NR_WRITTEN);
 	}
 	__unlock_page_memcg(memcg);
 	return ret;
-- 
2.30.0