Re: [PATCH v3 1/2] Btrfs: rework ulist with list+rb_tree

[Josef Bacik <jbacik@fb.com>]

On 01/27/2014 04:59 AM, Wang Shilong wrote:
> We are really suffering from now ulist's implementation, some developers
> gave their try, and i just gave some of my ideas for things:
>
>   1. use list+rb_tree instead of arrary+rb_tree
>
>   2. add cur_list to iterator rather than ulist structure.
>
>   3. add seqnum into every node when they are added, this is
>   used to do selfcheck when iterating node.
>
> I noticed Zach Brown's comments before, long term is to kick off
> ulist implementation, however, for now, we need at least avoid
> arrary from ulist.
>
> Cc: Liu Bo <bo.li.liu@oracle.com>
> Cc: Josef Bacik <jbacik@fb.com>
> Cc: Zach Brown <zab@redhat.com>
> Signed-off-by: Wang Shilong <wangsl.fnst@cn.fujitsu.com>
> ---
> v2->v3:
> 	only do selfchecks with CONFIG_BTRFS_DEBUG enabled(Thanks to Josef!)
> 	update ulist's comments since they are out of date.
> v1->v2:
> 	add RFC title since this patch needs more reviews and comments.
> 	fix a used after free bug in ulist_fini().

I like the patch but it doesn't build since things like qgroups rely on 
ulist->nnodes.  You need to fix that in your patch and make sure this 
stuff compiles.  Thanks,

Josef