commit 3199a0f02fdd8379bd8694ac57f307234075d0c2
Author: Andre Przywara <andre.przywara@amd.com>
Date:   Thu Feb 4 13:51:53 2010 +0100

    added xc_nodeload() function

diff --git a/tools/libxc/xc_misc.c b/tools/libxc/xc_misc.c
index 04da3d2..9ae61b6 100644
--- a/tools/libxc/xc_misc.c
+++ b/tools/libxc/xc_misc.c
@@ -424,6 +424,70 @@ xc_map_foreign_bulk(int xc_handle, uint32_t dom, int prot,
     return ret;
 }
 
+#define MAX_DOMS 8
+#define MAX_CPU_ID 255
+
+struct xc_nodeload* xc_getnodeload(int xc_handle,
+                                   int *ret_nrnodes)
+{
+       xc_dominfo_t dominfo[MAX_DOMS];
+       xc_vcpuinfo_t vcpuinfo;
+       int nextdom = 0;
+       int nrdoms, dom, vcpu, i;
+       xc_physinfo_t physinfo;
+       uint32_t nodemap[MAX_CPU_ID + 1];
+       int nrcpus, nrnodes, sum;
+       uint64_t cpumap;
+       int *curload;
+    struct xc_nodeload *nodeload;
+
+       set_xen_guest_handle(physinfo.cpu_to_node, nodemap);
+       physinfo.max_cpu_id = MAX_CPU_ID;
+
+    if (xc_physinfo(xc_handle, &physinfo) != 0)
+        return NULL;
+    nrnodes = physinfo.max_node_id + 1;
+    nrcpus = physinfo.max_cpu_id + 1;
+    curload = malloc(nrnodes * sizeof(int));
+    nodeload = malloc(nrnodes * sizeof(struct xc_nodeload));
+    for (i = 0; i < nrnodes; i++) {
+        nodeload[i].node = i;
+        nodeload[i].load = 0;
+        xc_availheap(xc_handle, 0, 0, i, &nodeload[i].freemem);
+        nodeload[i].freemem /= 1024;
+    }
+
+    while ((nrdoms = xc_domain_getinfo(xc_handle,
+                                       nextdom, MAX_DOMS, dominfo)) != -1) {
+        for (dom = 0; dom < nrdoms; dom++) {
+            for (vcpu = 0; vcpu <= dominfo[dom].max_vcpu_id; vcpu++) {
+                xc_vcpu_getinfo(xc_handle, dominfo[dom].domid, vcpu, &vcpuinfo);
+                if (!vcpuinfo.online)
+                    continue;
+                   xc_vcpu_getaffinity(xc_handle, dominfo[dom].domid, vcpu,
+                                       &cpumap);
+                memset(curload, 0, sizeof(int) * nrnodes);
+                for (i = sum = 0; i < nrcpus; i++) {
+                               if ((1ULL << i) & cpumap) {
+                                       if (curload[nodemap[i]] == 0)
+                                               sum++;
+                                       curload[nodemap[i]] = 1;
+                               }
+                }
+                for (i = 0; i < nrnodes; i++)
+                   nodeload[i].load += curload[i] * nrnodes / sum;
+            }
+        }
+        if (nrdoms < 2)
+            break;
+        nextdom = dominfo[nrdoms - 1].domid + 1;
+    }
+    free(curload);
+    if (ret_nrnodes != NULL)
+        *ret_nrnodes = nrnodes;
+    return nodeload;
+}
+
 /*
  * Local variables:
  * mode: C
diff --git a/tools/libxc/xenctrl.h b/tools/libxc/xenctrl.h
index 79c1fd4..0b6ef9a 100644
--- a/tools/libxc/xenctrl.h
+++ b/tools/libxc/xenctrl.h
@@ -613,6 +613,22 @@ typedef uint32_t xc_cpu_to_node_t;
 int xc_physinfo(int xc_handle,
                 xc_physinfo_t *info);
 
+struct xc_nodeload {
+    int node;
+    int load;
+    uint64_t freemem;
+};
+
+/* Iterate over all domains and VCPUs to get an estimate of the load
+ * distribution of the NUMA nodes. Returns the malloced array with
+ * an entry for each node. ret_nrnodes is optional (can be NULL) and
+ * contains the number of entries in the array.
+ * The node member contains the node number, useful if you sort the array.
+ * The load value is a relative metric, freemem is given in KB.
+ */
+struct xc_nodeload* xc_getnodeload(int xc_handle,
+                                   int *ret_nrnodes);
+
 int xc_sched_id(int xc_handle,
                 int *sched_id);