From 0abd8e70d24b665dd00972d4a259e05528cbf4c6 Mon Sep 17 00:00:00 2001
From: Daeho Jeong <daeho.jeong@samsung.com>
Date: Mon, 11 Sep 2017 16:30:28 +0900
Subject: [PATCH] f2fs: clear radix tree dirty tag of pages whose dirty flag is
 cleared

On a senario like writing out the first dirty page of the inode
as the inline data, we only cleared dirty flags of the pages, but
didn't clear the dirty tags of those pages in the radix tree.

If we don't clear the dirty tags of the pages in the radix tree, the
inodes which contain the pages will be marked with I_DIRTY_PAGES again
and again, and writepages() for the inodes will be invoked in every
writeback period. As a result, nothing will be done in every
writepages() for the inodes and it will just consume CPU time
meaninglessly.

Signed-off-by: Daeho Jeong <daeho.jeong@samsung.com>
Reviewed-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
---
 fs/f2fs/dir.c    | 7 +++++++
 fs/f2fs/inline.c | 7 +++++++
 2 files changed, 14 insertions(+)

diff --git a/fs/f2fs/dir.c b/fs/f2fs/dir.c
index 37f9c7f556058..c0c933ad43c8d 100644
--- a/fs/f2fs/dir.c
+++ b/fs/f2fs/dir.c
@@ -705,6 +705,8 @@ void f2fs_delete_entry(struct f2fs_dir_entry *dentry, struct page *page,
 	struct	f2fs_dentry_block *dentry_blk;
 	unsigned int bit_pos;
 	int slots = GET_DENTRY_SLOTS(le16_to_cpu(dentry->name_len));
+	struct address_space *mapping = page_mapping(page);
+	unsigned long flags;
 	int i;
 
 	f2fs_update_time(F2FS_I_SB(dir), REQ_TIME);
@@ -735,6 +737,11 @@ void f2fs_delete_entry(struct f2fs_dir_entry *dentry, struct page *page,
 
 	if (bit_pos == NR_DENTRY_IN_BLOCK &&
 			!truncate_hole(dir, page->index, page->index + 1)) {
+		spin_lock_irqsave(&mapping->tree_lock, flags);
+		radix_tree_tag_clear(&mapping->page_tree, page_index(page),
+				     PAGECACHE_TAG_DIRTY);
+		spin_unlock_irqrestore(&mapping->tree_lock, flags);
+
 		clear_page_dirty_for_io(page);
 		ClearPagePrivate(page);
 		ClearPageUptodate(page);
diff --git a/fs/f2fs/inline.c b/fs/f2fs/inline.c
index c133a4fdecf62..8322e4e7bb3fc 100644
--- a/fs/f2fs/inline.c
+++ b/fs/f2fs/inline.c
@@ -202,6 +202,8 @@ int f2fs_write_inline_data(struct inode *inode, struct page *page)
 {
 	void *src_addr, *dst_addr;
 	struct dnode_of_data dn;
+	struct address_space *mapping = page_mapping(page);
+	unsigned long flags;
 	int err;
 
 	set_new_dnode(&dn, inode, NULL, NULL, 0);
@@ -223,6 +225,11 @@ int f2fs_write_inline_data(struct inode *inode, struct page *page)
 	kunmap_atomic(src_addr);
 	set_page_dirty(dn.inode_page);
 
+	spin_lock_irqsave(&mapping->tree_lock, flags);
+	radix_tree_tag_clear(&mapping->page_tree, page_index(page),
+			     PAGECACHE_TAG_DIRTY);
+	spin_unlock_irqrestore(&mapping->tree_lock, flags);
+
 	set_inode_flag(inode, FI_APPEND_WRITE);
 	set_inode_flag(inode, FI_DATA_EXIST);
 
-- 
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