xend: Fix and improve default NUMA node selection.

Add the missing condition check and use average value instead of the
sum value of Vcpus pinning cpus on certain node to choose relaxed node.

Signed-off-by: Duan Ronghui <ronghui.duan@intel.com>

tools/python/xen/xend/XendDomainInfo.py

@@ -2062,36 +2062,44 @@ class XendDomainInfo:
                 for v in range(0, self.info['VCPUs_max']):
                     xc.vcpu_setaffinity(self.domid, v, self.info['cpus'])
             else:
+                def find_relaxed_node(node_list):
+                    import sys 
+                    if node_list is None:
+                        node_list = range(0, info['nr_nodes'])
+                    nodeload = [0]
+                    nodeload = nodeload * info['nr_nodes']
+                    from xen.xend import XendDomain
+                    doms = XendDomain.instance().list('all')
+                    for dom in doms:
+                        cpuinfo = dom.getVCPUInfo()
+                        for vcpu in sxp.children(cpuinfo, 'vcpu'):
+                            def vinfo(n, t):
+                                return t(sxp.child_value(vcpu, n))
+                            cpumap = vinfo('cpumap', list)
+                            for i in node_list:
+                                node_cpumask = info['node_to_cpu'][i]
+                                for j in node_cpumask:
+                                    if j in cpumap:
+                                        nodeload[i] += 1
+                                        break
+                    for i in node_list:
+                        if len(info['node_to_cpu'][i]) > 0:
+                            nodeload[i] = int(nodeload[i] / len(info['node_to_cpu'][i]))
+                        else:
+                            nodeload[i] = sys.maxint
+                    index = nodeload.index( min(nodeload) )    
+                    return index
+
                 info = xc.physinfo()
                 if info['nr_nodes'] > 1:
                     node_memory_list = info['node_to_memory']
                     needmem = self.image.getRequiredAvailableMemory(self.info['memory_dynamic_max']) / 1024
                     candidate_node_list = []
                     for i in range(0, info['nr_nodes']):
-                        if node_memory_list[i] >= needmem:
+                        if node_memory_list[i] >= needmem and len(info['node_to_cpu'][i]) > 0:
                             candidate_node_list.append(i)
-                    if candidate_node_list is None or len(candidate_node_list) == 1:
-                        index = node_memory_list.index( max(node_memory_list) )
-                        cpumask = info['node_to_cpu'][index]
-                    else:
-                        nodeload = [0]
-                        nodeload = nodeload * info['nr_nodes']
-                        from xen.xend import XendDomain
-                        doms = XendDomain.instance().list('all')
-                        for dom in doms:
-                            cpuinfo = dom.getVCPUInfo()
-                            for vcpu in sxp.children(cpuinfo, 'vcpu'):
-                                def vinfo(n, t):
-                                    return t(sxp.child_value(vcpu, n))
-                                cpumap = vinfo('cpumap', list)
-                                for i in candidate_node_list:
-                                    node_cpumask = info['node_to_cpu'][i]
-                                    for j in node_cpumask:
-                                        if j in cpumap:
-                                            nodeload[i] += 1
-                                            break
-                        index = nodeload.index( min(nodeload) )
-                        cpumask = info['node_to_cpu'][index]
+                    index = find_relaxed_node(candidate_node_list)
+                    cpumask = info['node_to_cpu'][index]
                     for v in range(0, self.info['VCPUs_max']):
                         xc.vcpu_setaffinity(self.domid, v, cpumask)