Re: [PATCH] Reflect cpupool in numa node affinity

[Juergen Gross <juergen.gross@ts.fujitsu.com>]

On 01/23/2012 12:03 PM, Ian Campbell wrote:
> On Mon, 2012-01-23 at 09:51 +0000, Juergen Gross wrote:
>> @@ -365,15 +366,21 @@ void domain_update_node_affinity(struct
>>   void domain_update_node_affinity(struct domain *d)
>>   {
>>       cpumask_t cpumask;
>> +    cpumask_t online_affinity;
>> +    cpumask_t *online;
>>       nodemask_t nodemask = NODE_MASK_NONE;
>>       struct vcpu *v;
>>       unsigned int node;
>>
>> +    online = (d->cpupool == NULL) ?&cpu_online_map : d->cpupool->cpu_valid;
>>       cpumask_clear(&cpumask);
>>       spin_lock(&d->node_affinity_lock);
>>
>>       for_each_vcpu ( d, v )
>> -        cpumask_or(&cpumask,&cpumask, v->cpu_affinity);
>> +    {
>> +        cpumask_and(&online_affinity, v->cpu_affinity, online);
>> +        cpumask_or(&cpumask,&cpumask,&online_affinity);
>> +    }
>>
>>       for_each_online_node ( node )
>>           if ( cpumask_intersects(&node_to_cpumask(node),&cpumask) )
> Is there any possibility that the addition of the cpumask_and clause
> could result in the empty set?

No. v->cpu_affinity is set to all ones if:
- the domain is moved to another cpupool
- the last cpu which is set in v->cpu_affinity is removed from the cpupool the
   domain is assigned to


Juergen

-- 
Juergen Gross                 Principal Developer Operating Systems
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