f2fs: avoid unnecessary f2fs_gc for dir operations

The f2fs_balance_fs doesn't need to cover f2fs_new_inode or f2fs_find_entry
works.

Reviewed-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
diff --git a/fs/f2fs/namei.c b/fs/f2fs/namei.c
index 2c32110..4e27c5c 100644
--- a/fs/f2fs/namei.c
+++ b/fs/f2fs/namei.c
@@ -128,8 +128,6 @@
 	nid_t ino = 0;
 	int err;
 
-	f2fs_balance_fs(sbi);
-
 	inode = f2fs_new_inode(dir, mode);
 	if (IS_ERR(inode))
 		return PTR_ERR(inode);
@@ -142,6 +140,8 @@
 	inode->i_mapping->a_ops = &f2fs_dblock_aops;
 	ino = inode->i_ino;
 
+	f2fs_balance_fs(sbi);
+
 	f2fs_lock_op(sbi);
 	err = f2fs_add_link(dentry, inode);
 	if (err)
@@ -288,12 +288,13 @@
 	int err = -ENOENT;
 
 	trace_f2fs_unlink_enter(dir, dentry);
-	f2fs_balance_fs(sbi);
 
 	de = f2fs_find_entry(dir, &dentry->d_name, &page);
 	if (!de)
 		goto fail;
 
+	f2fs_balance_fs(sbi);
+
 	f2fs_lock_op(sbi);
 	err = acquire_orphan_inode(sbi);
 	if (err) {
@@ -341,8 +342,6 @@
 	if (len > dir->i_sb->s_blocksize)
 		return -ENAMETOOLONG;
 
-	f2fs_balance_fs(sbi);
-
 	inode = f2fs_new_inode(dir, S_IFLNK | S_IRWXUGO);
 	if (IS_ERR(inode))
 		return PTR_ERR(inode);
@@ -353,6 +352,8 @@
 		inode->i_op = &f2fs_symlink_inode_operations;
 	inode->i_mapping->a_ops = &f2fs_dblock_aops;
 
+	f2fs_balance_fs(sbi);
+
 	f2fs_lock_op(sbi);
 	err = f2fs_add_link(dentry, inode);
 	if (err)
@@ -433,8 +434,6 @@
 	struct inode *inode;
 	int err;
 
-	f2fs_balance_fs(sbi);
-
 	inode = f2fs_new_inode(dir, S_IFDIR | mode);
 	if (IS_ERR(inode))
 		return PTR_ERR(inode);
@@ -444,6 +443,8 @@
 	inode->i_mapping->a_ops = &f2fs_dblock_aops;
 	mapping_set_gfp_mask(inode->i_mapping, GFP_F2FS_HIGH_ZERO);
 
+	f2fs_balance_fs(sbi);
+
 	set_inode_flag(F2FS_I(inode), FI_INC_LINK);
 	f2fs_lock_op(sbi);
 	err = f2fs_add_link(dentry, inode);
@@ -481,8 +482,6 @@
 	struct inode *inode;
 	int err = 0;
 
-	f2fs_balance_fs(sbi);
-
 	inode = f2fs_new_inode(dir, mode);
 	if (IS_ERR(inode))
 		return PTR_ERR(inode);
@@ -490,6 +489,8 @@
 	init_special_inode(inode, inode->i_mode, rdev);
 	inode->i_op = &f2fs_special_inode_operations;
 
+	f2fs_balance_fs(sbi);
+
 	f2fs_lock_op(sbi);
 	err = f2fs_add_link(dentry, inode);
 	if (err)
@@ -516,9 +517,6 @@
 	struct inode *inode;
 	int err;
 
-	if (!whiteout)
-		f2fs_balance_fs(sbi);
-
 	inode = f2fs_new_inode(dir, mode);
 	if (IS_ERR(inode))
 		return PTR_ERR(inode);
@@ -532,6 +530,8 @@
 		inode->i_mapping->a_ops = &f2fs_dblock_aops;
 	}
 
+	f2fs_balance_fs(sbi);
+
 	f2fs_lock_op(sbi);
 	err = acquire_orphan_inode(sbi);
 	if (err)
@@ -604,8 +604,6 @@
 		goto out;
 	}
 
-	f2fs_balance_fs(sbi);
-
 	old_entry = f2fs_find_entry(old_dir, &old_dentry->d_name, &old_page);
 	if (!old_entry)
 		goto out;
@@ -635,6 +633,8 @@
 		if (!new_entry)
 			goto out_whiteout;
 
+		f2fs_balance_fs(sbi);
+
 		f2fs_lock_op(sbi);
 
 		err = acquire_orphan_inode(sbi);
@@ -666,6 +666,8 @@
 		update_inode_page(old_inode);
 		update_inode_page(new_inode);
 	} else {
+		f2fs_balance_fs(sbi);
+
 		f2fs_lock_op(sbi);
 
 		err = f2fs_add_link(new_dentry, old_inode);
@@ -763,8 +765,6 @@
 								new_inode)))
 		return -EPERM;
 
-	f2fs_balance_fs(sbi);
-
 	old_entry = f2fs_find_entry(old_dir, &old_dentry->d_name, &old_page);
 	if (!old_entry)
 		goto out;
@@ -807,6 +807,8 @@
 			goto out_new_dir;
 	}
 
+	f2fs_balance_fs(sbi);
+
 	f2fs_lock_op(sbi);
 
 	err = update_dent_inode(old_inode, new_inode, &new_dentry->d_name);