[Libvir] PATCH: Compatability with Xen 3.2.0

[Daniel P. Berrange]

In Xen 3.2.0 the  physinfo hypercall was changed to remove the field
'sockets_per_node' and add in 'nr_cpus'. We use the sockets_per_node field
in livirt for the  virNodeInfo struct :-(  This patch re-calculates its
value in terms of 'nr_cpus / (nodes*cores*threads)' which is how older
Xen used to figure it out.

Dan.
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-------------- next part --------------
Index: src/xend_internal.c
===================================================================
RCS file: /data/cvs/libvirt/src/xend_internal.c,v
retrieving revision 1.157
diff -u -p -r1.157 xend_internal.c
--- src/xend_internal.c	5 Dec 2007 18:28:05 -0000	1.157
+++ src/xend_internal.c	17 Dec 2007 19:16:32 -0000
@@ -1893,11 +1893,11 @@ sexpr_to_xend_node_info(struct sexpr *ro
         return (-1);
 
     machine = sexpr_node(root, "node/machine");
-    if (machine == NULL)
+    if (machine == NULL) {
         info->model[0] = 0;
-    else {
+    } else {
         snprintf(&info->model[0], sizeof(info->model) - 1, "%s", machine);
-	info->model[sizeof(info->model) - 1] = 0;
+        info->model[sizeof(info->model) - 1] = 0;
     }
     info->memory = (unsigned long) sexpr_u64(root, "node/total_memory") << 10;
 
@@ -1905,6 +1905,20 @@ sexpr_to_xend_node_info(struct sexpr *ro
     info->mhz = sexpr_int(root, "node/cpu_mhz");
     info->nodes = sexpr_int(root, "node/nr_nodes");
     info->sockets = sexpr_int(root, "node/sockets_per_node");
+    /* Xen 3.2.0 replaces sockets_per_node with 'nr_cpus'.
+     * Old Xen calculated sockets_per_node using its internal
+     * nr_cpus / (nodes*cores*threads), so fake it ourselves
+     * in the same way
+     */
+    if (info->sockets == 0) {
+        int nr_cpus = sexpr_int(root, "node/nr_cpus");
+        info->sockets = nr_cpus / (info->nodes * info->cores * info->threads);
+        /* Should already be fine, but for sanity make
+         * sure we have at least one socket
+         */
+        if (info->sockets == 0)
+            info->sockets = 1;
+    }
     info->cores = sexpr_int(root, "node/cores_per_socket");
     info->threads = sexpr_int(root, "node/threads_per_core");
     return (0);