Re: [PATCH] Btrfs: cleanup to remove reduplicate code in iterate_extent_inode()

[Arne Jansen <sensille@gmx.net>]

On 03/30/13 12:55, Wang Shilong wrote:
> <snip>
> 
>> On 03/29/13 14:42, Wang Shilong wrote:
>>> From: Wang Shilong <wangsl-fnst@cn.fujitsu.com>
>>>
>>> Just remove the unnecessary check and assignment.
>>>
>>> Signed-off-by: Wang Shilong <wangsl-fnst@cn.fujitsu.com>
>>> ---
>>> fs/btrfs/backref.c | 3 +--
>>> 1 file changed, 1 insertion(+), 2 deletions(-)
>>>
>>> diff --git a/fs/btrfs/backref.c b/fs/btrfs/backref.c
>>> index 3ca413bb..e102b48 100644
>>> --- a/fs/btrfs/backref.c
>>> +++ b/fs/btrfs/backref.c
>>> @@ -1499,7 +1499,7 @@ int iterate_extent_inodes(struct btrfs_fs_info *fs_info,
>>> 		if (ret)
>>> 			break;
>>> 		ULIST_ITER_INIT(&root_uiter);
>>> -		while (!ret && (root_node = ulist_next(roots, &root_uiter))) {
>>> +		while ((root_node = ulist_next(roots, &root_uiter))) {
>>
>> It doesn't look unnecessary at all to me. ret is set in the loop and
>> only checked in the while condition.
>>
>>> 			pr_debug("root %llu references leaf %llu, data list "
>>> 				 "%#llx\n", root_node->val, ref_node->val,
>>> 				 (long long)ref_node->aux);
>>> @@ -1510,7 +1510,6 @@ int iterate_extent_inodes(struct btrfs_fs_info *fs_info,
>>> 						iterate, ctx);
>>> 		}
>>> 		ulist_free(roots);
>>> -		roots = NULL;
>>
>> roots gets freed again later on. If you don't set it to NULL, it will
>> result in a double free.
> 
> Maybe you mean this?
> 
> http://marc.info/?l=linux-btrfs&m=136456233929528&w=2
> ulist_free() here is unnecessary and may cause a double free…
> So we don't need to set it to NULL again..

Yeah, I haven't seen your other patch.

> 
> 
> 
>>
>> -Arne
>>
>>> 	}
>>>
>>> 	free_leaf_list(refs);
>>>
>>
>