[sheepdog] [PATCH] sheep: update node in cluster driver

[Liu Yuan]

On 05/31/2013 08:52 PM, MORITA Kazutaka wrote:
> At Fri, 31 May 2013 18:35:59 +0800,
> Liu Yuan wrote:
>>
>> diff --git a/sheep/group.c b/sheep/group.c
>> index b9399ee..f74ef10 100644
>> --- a/sheep/group.c
>> +++ b/sheep/group.c
>> @@ -1242,6 +1242,7 @@ void update_node_size(struct sd_node *node)
>>  	int idx = get_node_idx(cur_vinfo, node);
>>  	assert(idx != -1);
>>  	cur_vinfo->nodes[idx].space = node->space;
>> +	sys->cdrv->update_node(node);
>>  }
> 
> The current cluster driver model is:
> 
>  - Sheep triggers a node event with a cluster driver interface.
>  - The cluster driver updates its internal state, and invokes a
>    callback to notify the change to sheep.
> 
> In that sense, this fix is a bit weird to me.
> 
> I think a better fix is:
> 
>  1. make SD_OP_REWEIGHT a local request.
>  2. call cdrv->update_node() in cluster_reweight().
>  3. order the update_node event with other nonblocking events and call
>     sd_update_node() as a callback of the update_node event.
>  4. call update_node_size() and kick_node_recover() in sd_update_node()
> 
> Then, we can remove a SD_OP_UPDATE_SIZE operation and FIXME in the
> local driver.
> 
> That being said, the current fix also looks correct to me (except the
> local driver), so I'm fine with merging this code without changes.
> 

Yeah, your fix looks better integrated but this patch win as a simpler
with less change approach and the node can be updated inside a ordered
notify event. Local driver just a test driver so there is nothing to worry.

That said, I'd like to merge my fix for 0.6.0 and prepare a another
patch as you described.

Thanks,
Yuan