+ buffer-use-b_folio-in-mark_buffer_dirty.patch added to mm-unstable branch

+ buffer-use-b_folio-in-mark_buffer_dirty.patch added to mm-unstable branch

[Andrew Morton]

The patch titled
     Subject: buffer: use b_folio in mark_buffer_dirty()
has been added to the -mm mm-unstable branch.  Its filename is
     buffer-use-b_folio-in-mark_buffer_dirty.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/buffer-use-b_folio-in-mark_buffer_dirty.patch

This patch will later appear in the mm-unstable branch at
    git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

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------------------------------------------------------
From: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Subject: buffer: use b_folio in mark_buffer_dirty()
Date: Thu, 15 Dec 2022 21:43:57 +0000

Removes about four calls to compound_head().  Two of them are inline which
removes 132 bytes from the kernel text.

Link: https://lkml.kernel.org/r/20221215214402.3522366-8-willy@infradead.org
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 fs/buffer.c |   12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

--- a/fs/buffer.c~buffer-use-b_folio-in-mark_buffer_dirty
+++ a/fs/buffer.c
@@ -1095,16 +1095,16 @@ void mark_buffer_dirty(struct buffer_hea
 	}
 
 	if (!test_set_buffer_dirty(bh)) {
-		struct page *page = bh->b_page;
+		struct folio *folio = bh->b_folio;
 		struct address_space *mapping = NULL;
 
-		lock_page_memcg(page);
-		if (!TestSetPageDirty(page)) {
-			mapping = page_mapping(page);
+		folio_memcg_lock(folio);
+		if (!folio_test_set_dirty(folio)) {
+			mapping = folio->mapping;
 			if (mapping)
-				__set_page_dirty(page, mapping, 0);
+				__folio_mark_dirty(folio, mapping, 0);
 		}
-		unlock_page_memcg(page);
+		folio_memcg_unlock(folio);
 		if (mapping)
 			__mark_inode_dirty(mapping->host, I_DIRTY_PAGES);
 	}
_

Patches currently in -mm which might be from willy@infradead.org are

buffer-add-b_folio-as-an-alias-of-b_page.patch
buffer-replace-obvious-uses-of-b_page-with-b_folio.patch
buffer-use-b_folio-in-touch_buffer.patch
buffer-use-b_folio-in-end_buffer_async_read.patch
buffer-use-b_folio-in-end_buffer_async_write.patch
page_io-remove-buffer_head-include.patch
buffer-use-b_folio-in-mark_buffer_dirty.patch
gfs2-replace-obvious-uses-of-b_page-with-b_folio.patch
jbd2-replace-obvious-uses-of-b_page-with-b_folio.patch
nilfs2-replace-obvious-uses-of-b_page-with-b_folio.patch
reiserfs-replace-obvious-uses-of-b_page-with-b_folio.patch
mpage-use-b_folio-in-do_mpage_readpage.patch