f2fs: skip writing in ->writepages when no dirty pages exist
When flushing comes from background, if there is no dirty page in the
mapping of inode, we'd better to skip seeking dirty page from mapping
for writebacking.
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c
index 801b0b0..e4081fc 100644
--- a/fs/f2fs/data.c
+++ b/fs/f2fs/data.c
@@ -1275,6 +1275,10 @@
if (!mapping->a_ops->writepage)
return 0;
+ /* skip writing if there is no dirty page in this inode */
+ if (!get_dirty_pages(inode) && wbc->sync_mode == WB_SYNC_NONE)
+ return 0;
+
if (S_ISDIR(inode->i_mode) && wbc->sync_mode == WB_SYNC_NONE &&
get_dirty_pages(inode) < nr_pages_to_skip(sbi, DATA) &&
available_free_memory(sbi, DIRTY_DENTS))