1 files changed, 13 insertions, 9 deletions

diff --git a/fs/fs-writeback.c b/fs/fs-writeback.c
index 518c6294bf6c..5fa588e933d5 100644
--- a/fs/fs-writeback.c
+++ b/fs/fs-writeback.c
@@ -844,14 +844,15 @@ static void bdi_split_work_to_wbs(struct backing_dev_info *bdi,
         struct wb_iter iter;
 
         might_sleep();
-
-        if (!bdi_has_dirty_io(bdi))
-                return;
 restart:
         rcu_read_lock();
         bdi_for_each_wb(wb, bdi, &iter, next_blkcg_id) {
-                if (!wb_has_dirty_io(wb) ||
-                    (skip_if_busy && writeback_in_progress(wb)))
+                /* SYNC_ALL writes out I_DIRTY_TIME too */
+                if (!wb_has_dirty_io(wb) &&
+                    (base_work->sync_mode == WB_SYNC_NONE ||
+                     list_empty(&wb->b_dirty_time)))
+                        continue;
+                if (skip_if_busy && writeback_in_progress(wb))
                         continue;
 
                 base_work->nr_pages = wb_split_bdi_pages(wb, nr_pages);
@@ -899,8 +900,7 @@ static void bdi_split_work_to_wbs(struct backing_dev_info *bdi,
 {
         might_sleep();
 
-        if (bdi_has_dirty_io(bdi) &&
-            (!skip_if_busy || !writeback_in_progress(&bdi->wb))) {
+        if (!skip_if_busy || !writeback_in_progress(&bdi->wb)) {
                 base_work->auto_free = 0;
                 base_work->single_wait = 0;
                 base_work->single_done = 0;
@@ -2275,8 +2275,12 @@ void sync_inodes_sb(struct super_block *sb)
         };
         struct backing_dev_info *bdi = sb->s_bdi;
 
-        /* Nothing to do? */
-        if (!bdi_has_dirty_io(bdi) || bdi == &noop_backing_dev_info)
+        /*
+         * Can't skip on !bdi_has_dirty() because we should wait for !dirty
+         * inodes under writeback and I_DIRTY_TIME inodes ignored by
+         * bdi_has_dirty() need to be written out too.
+         */
+        if (bdi == &noop_backing_dev_info)
                 return;
         WARN_ON(!rwsem_is_locked(&sb->s_umount));