[11/13] writeback: Move the folio_prepare_writeback loop out of write_cache_pages()
Commit Message
From: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Move the loop for should-we-write-this-folio to writeback_get_folio.
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
[hch: folded the loop into the existing helper instead of a separate one
as suggested by Jan Kara]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Jan Kara <jack@suse.cz>
Acked-by: Dave Chinner <dchinner@redhat.com>
---
mm/page-writeback.c | 18 ++++++++++--------
1 file changed, 10 insertions(+), 8 deletions(-)
@@ -2411,6 +2411,7 @@ static struct folio *writeback_get_folio(struct address_space *mapping,
{
struct folio *folio;
+retry:
folio = folio_batch_next(&wbc->fbatch);
if (!folio) {
folio_batch_release(&wbc->fbatch);
@@ -2418,8 +2419,17 @@ static struct folio *writeback_get_folio(struct address_space *mapping,
filemap_get_folios_tag(mapping, &wbc->index, wbc_end(wbc),
wbc_to_tag(wbc), &wbc->fbatch);
folio = folio_batch_next(&wbc->fbatch);
+ if (!folio)
+ return NULL;
+ }
+
+ folio_lock(folio);
+ if (unlikely(!folio_prepare_writeback(mapping, wbc, folio))) {
+ folio_unlock(folio);
+ goto retry;
}
+ trace_wbc_writepage(wbc, inode_to_bdi(mapping->host));
return folio;
}
@@ -2480,14 +2490,6 @@ int write_cache_pages(struct address_space *mapping,
if (!folio)
break;
- folio_lock(folio);
- if (!folio_prepare_writeback(mapping, wbc, folio)) {
- folio_unlock(folio);
- continue;
- }
-
- trace_wbc_writepage(wbc, inode_to_bdi(mapping->host));
-
error = writepage(folio, wbc, data);
wbc->nr_to_write -= folio_nr_pages(folio);