# HG changeset patch
# User Keir Fraser <keir.fraser@citrix.com>
# Date 1263751268 0
# Node ID 36c40adffe126f77bb661895c8a507112988c881
# Parent  8bbb0dd9a340a3ae7011b35945d496d4d1910818
xend: NUMA: fix division by zero on unpopulated nodes

nodes without memory will currently be disabled by also moving the
physical cores connected to them to other nodes. This leads to nodes
without CPUs and thus to a division by zero in the node allocation
algorithm.  Attached patch fixes this by checking for 0 before the
division. This fixes domain creation on boxes with memory-less nodes.

Signed-off-by: Andre Przywara <andre.przywara@amd.com>

diff -r 8bbb0dd9a340 -r 36c40adffe12 tools/python/xen/xend/XendDomainInfo.py
--- a/tools/python/xen/xend/XendDomainInfo.py	Sun Jan 17 17:57:44 2010 +0000
+++ b/tools/python/xen/xend/XendDomainInfo.py	Sun Jan 17 18:01:08 2010 +0000
@@ -2709,9 +2709,12 @@ class XendDomainInfo:
                                     nodeload[i] += 1
                                     break
                 for i in range(0, nr_nodes):
-                    nodeload[i] = int(nodeload[i] * 16 / len(info['node_to_cpu'][i]))
-                    if len(info['node_to_cpu'][i]) == 0 or i not in node_list:
+                    if len(info['node_to_cpu'][i]) == 0:
                         nodeload[i] += 8
+                    else:
+                        nodeload[i] = int(nodeload[i] * 16 / len(info['node_to_cpu'][i]))
+                        if i not in node_list:
+                            nodeload[i] += 8
                 return map(lambda x: x[0], sorted(enumerate(nodeload), key=lambda x:x[1]))
 
             info = xc.physinfo()