[Ocfs2-devel] [PATCH 1/2] Introduce ocfs2_recover_node

[Sunil Mushran <sunil.mushran@oracle.com>]

On 12/01/2010 09:29 PM, Joel Becker wrote:
> On Wed, Nov 17, 2010 at 09:50:04AM -0600, Goldwyn Rodrigues wrote:
>> @@ -1470,7 +1451,11 @@ void ocfs2_recovery_thread(struct ocfs2_super
>> *osb, int node_num)
>>
>>   	/* People waiting on recovery will wait on
>>   	 * the recovery map to empty. */
>> -	if (ocfs2_recovery_map_set(osb, node_num))
>> +	ret = ocfs2_recovery_node_set(osb, node_num);
>> +	if (ret == -ENOMEM) {
>> +		mlog_errno(ret);
>> +		goto out;
>> +	} else if (ret)
>>   		mlog(0, "node %d already in recovery map.\n", node_num);
> 	This is a broken change.  If we get -ENOMEM, we won't block
> other processes.  We can't have that happen.  There are two possible
> solutions.  First, like Sunil said, we can preallocate max_slots recovery
> entries.  Seems pretty sane.  The other solution would be to set an
> in-recovery flag that others can check, so even when the recovery list
> is empty because of a failed allocation, other processes still block.  I
> prefer the preallocation because it doesn't fail recovery.

You could stick with the list but preallocate max_slots items during init.
Attach all those to the s_init_reco_list. During set, move a item to
s_active_reco_list. Clear moves it back.