f2fs: fix dirty page accounting when redirty
We should de-account dirty counters for page when redirty in ->writepage().
Wu Fengguang described in 'commit 971767caf632190f77a40b4011c19948232eed75':
"writeback: fix dirtied pages accounting on redirty
De-account the accumulative dirty counters on page redirty.
Page redirties (very common in ext4) will introduce mismatch between
counters (a) and (b)
a) NR_DIRTIED, BDI_DIRTIED, tsk->nr_dirtied
b) NR_WRITTEN, BDI_WRITTEN
This will introduce systematic errors in balanced_rate and result in
dirty page position errors (ie. the dirty pages are no longer balanced
around the global/bdi setpoints)."
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>
diff --git a/fs/f2fs/node.c b/fs/f2fs/node.c
index 1f9cf21..8c14110 100644
--- a/fs/f2fs/node.c
+++ b/fs/f2fs/node.c
@@ -1193,6 +1193,7 @@
redirty_out:
dec_page_count(sbi, F2FS_DIRTY_NODES);
wbc->pages_skipped++;
+ account_page_redirty(page);
set_page_dirty(page);
return AOP_WRITEPAGE_ACTIVATE;
}