# Re: \[RFC\]\[PATCH 3/8 v2\] ext4: initialize extent status tree

- From: Zheng Liu \<hidden\>
- Date: 2012-09-24 04:45:04 
- List: linux-ext4
- Page: https://ratatoskr.run/linux-ext4/2012/09/67323
- Thread: https://ratatoskr.run/linux-ext4/2012/08/66633/t.md

```text
On Wed, Sep 19, 2012 at 03:05:41PM -0400, Theodore Ts'o wrote:
> On Wed, Aug 22, 2012 at 02:05:40PM +0800, Zheng Liu wrote:
> > diff --git a/fs/ext4/super.c b/fs/ext4/super.c
> > index 3e0851e..353b1fd 100644
> > --- a/fs/ext4/super.c
> > +++ b/fs/ext4/super.c
> > @@ -944,6 +944,7 @@ static struct inode *ext4_alloc_inode(struct super_block *sb)
> >  	memset(&ei->i_cached_extent, 0, sizeof(struct ext4_ext_cache));
> >  	INIT_LIST_HEAD(&ei->i_prealloc_list);
> >  	spin_lock_init(&ei->i_prealloc_lock);
> > +	ext4_es_init_tree(&ei->i_es_tree);
> >  	ei->i_reserved_data_blocks = 0;
> >  	ei->i_reserved_meta_blocks = 0;
> >  	ei->i_allocated_meta_blocks = 0;
> 
> This patch hunk immediately me ask, "so when does the extent_status
> tree get freed?"  And I believe the answer is that currently, since it
> only tracks delayed extents (and we're not using it for locking
> purposes), by the time we have evicted the inode and are ready to call
> ext4_clear_inode(), we should have released all of the nodes in the
> ext4_es_tree.   Is that correct?
> 
> If so, we might want to think about adding a sanity check to make sure
> that by the time we are done with the inode in ext4_evict_inode()
> (after we have forced writeback), the ext4_es_tree is empty.  Agreed?

Yes, I agree with you.  I will add a sanity check. :-)

Regards,
Zheng
```