[libvirt] [PATCHv3 5/6] capabilities: Add additional data to the NUMA topology info

[Peter Krempa]

This patch adds data gathering to the NUMA gathering files and adds
support for outputting the data. The test driver and xend driver need to
be adapted to fill sensible data to the structure in a future patch.
---
 src/conf/capabilities.c | 31 ++++++++++++++++----
 src/nodeinfo.c          | 76 +++++++++++++++++++++++++++++++++++++++++++++----
 2 files changed, 96 insertions(+), 11 deletions(-)

diff --git a/src/conf/capabilities.c b/src/conf/capabilities.c
index 575981c..4897b9a 100644
--- a/src/conf/capabilities.c
+++ b/src/conf/capabilities.c
@@ -688,27 +688,47 @@ virCapabilitiesDefaultGuestEmulator(virCapsPtr caps,
     return NULL;
 }

-static void
+static int
 virCapabilitiesFormatNUMATopology(virBufferPtr xml,
                                   size_t ncells,
                                   virCapsHostNUMACellPtr *cells)
 {
     int i;
     int j;
+    char *siblings;

     virBufferAddLit(xml, "    <topology>\n");
     virBufferAsprintf(xml, "      <cells num='%zu'>\n", ncells);
     for (i = 0; i < ncells; i++) {
         virBufferAsprintf(xml, "        <cell id='%d'>\n", cells[i]->num);
         virBufferAsprintf(xml, "          <cpus num='%d'>\n", cells[i]->ncpus);
-        for (j = 0; j < cells[i]->ncpus; j++)
-            virBufferAsprintf(xml, "            <cpu id='%d'/>\n",
+        for (j = 0; j < cells[i]->ncpus; j++) {
+            virBufferAsprintf(xml, "            <cpu id='%d'",
                               cells[i]->cpus[j].id);
+
+            if (cells[i]->cpus[j].siblings) {
+                if (!(siblings = virBitmapFormat(cells[i]->cpus[j].siblings))) {
+                    virReportOOMError();
+                    return -1;
+                }
+
+                virBufferAsprintf(xml,
+                                  " socket_id='%d' core_id='%d' siblings='%s'",
+                                  cells[i]->cpus[j].socket_id,
+                                  cells[i]->cpus[j].core_id,
+                                  siblings);
+                VIR_FREE(siblings);
+            }
+            virBufferAddLit(xml, "/>\n");
+        }
+
         virBufferAddLit(xml, "          </cpus>\n");
         virBufferAddLit(xml, "        </cell>\n");
     }
     virBufferAddLit(xml, "      </cells>\n");
     virBufferAddLit(xml, "    </topology>\n");
+
+    return 0;
 }

 /**
@@ -784,9 +804,10 @@ virCapabilitiesFormatXML(virCapsPtr caps)
         virBufferAddLit(&xml, "    </migration_features>\n");
     }

-    if (caps->host.nnumaCell)
+    if (caps->host.nnumaCell &&
         virCapabilitiesFormatNUMATopology(&xml, caps->host.nnumaCell,
-                                          caps->host.numaCell);
+                                          caps->host.numaCell) < 0)
+        return NULL;

     for (i = 0; i < caps->host.nsecModels; i++) {
         virBufferAddLit(&xml, "    <secmodel>\n");
diff --git a/src/nodeinfo.c b/src/nodeinfo.c
index c29769c..5ce7d4f 100644
--- a/src/nodeinfo.c
+++ b/src/nodeinfo.c
@@ -79,9 +79,11 @@ freebsdNodeGetCPUCount(void)
 #ifdef __linux__
 # define CPUINFO_PATH "/proc/cpuinfo"
 # define SYSFS_SYSTEM_PATH "/sys/devices/system"
+# define SYSFS_CPU_PATH SYSFS_SYSTEM_PATH"/cpu"
 # define PROCSTAT_PATH "/proc/stat"
 # define MEMINFO_PATH "/proc/meminfo"
 # define SYSFS_MEMORY_SHARED_PATH "/sys/kernel/mm/ksm"
+# define SYSFS_THREAD_SIBLINGS_LIST_LENGHT_MAX 1024

 # define LINUX_NB_CPU_STATS 4
 # define LINUX_NB_MEMORY_STATS_ALL 4
@@ -1473,6 +1475,59 @@ cleanup:
 # define MASK_CPU_ISSET(mask, cpu) \
   (((mask)[((cpu) / n_bits(*(mask)))] >> ((cpu) % n_bits(*(mask)))) & 1)

+static virBitmapPtr
+virNodeGetSiblingsList(const char *dir, int cpu_id)
+{
+    char *path = NULL;
+    char *buf = NULL;
+    virBitmapPtr ret = NULL;
+
+    if (virAsprintf(&path, "%s/cpu%u/topology/thread_siblings_list",
+                    dir, cpu_id) < 0) {
+        virReportOOMError();
+        goto cleanup;
+    }
+
+    if (virFileReadAll(path, SYSFS_THREAD_SIBLINGS_LIST_LENGHT_MAX, &buf) < 0)
+        goto cleanup;
+
+    if (virBitmapParse(buf, 0, &ret, NUMA_MAX_N_CPUS) < 0) {
+        virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
+                       _("Failed to parse thread siblings"));
+        goto cleanup;
+    }
+
+cleanup:
+    VIR_FREE(buf);
+    VIR_FREE(path);
+    return ret;
+}
+
+/* returns 1 on success, 0 if the detection failed and -1 on hard error */
+static int
+virNodeCapsFillCPUInfo(int cpu_id, virCapsHostNUMACellCPUPtr cpu)
+{
+    int tmp;
+    cpu->id = cpu_id;
+
+    if ((tmp = virNodeGetCpuValue(SYSFS_CPU_PATH, cpu_id,
+                                  "topology/physical_package_id", -1)) < 0)
+        return 0;
+
+    cpu->socket_id = tmp;
+
+    if ((tmp = virNodeGetCpuValue(SYSFS_CPU_PATH, cpu_id,
+                                  "topology/core_id", -1)) < 0)
+        return 0;
+
+    cpu->core_id = tmp;
+
+    if (!(cpu->siblings = virNodeGetSiblingsList(SYSFS_CPU_PATH, cpu_id)))
+        return -1;
+
+    return 0;
+}
+
 int
 nodeCapsInitNUMA(virCapsPtr caps)
 {
@@ -1483,6 +1538,7 @@ nodeCapsInitNUMA(virCapsPtr caps)
     int ret = -1;
     int max_n_cpus = NUMA_MAX_N_CPUS;
     int ncpus = 0;
+    bool topology_failed = false;

     if (numa_available() < 0)
         return 0;
@@ -1516,20 +1572,28 @@ nodeCapsInitNUMA(virCapsPtr caps)
         if (VIR_ALLOC_N(cpus, ncpus) < 0)
             goto cleanup;

-        for (ncpus = 0, i = 0 ; i < max_n_cpus ; i++)
-            if (MASK_CPU_ISSET(mask, i))
-                cpus[ncpus++].id = i;
+        for (ncpus = 0, i = 0 ; i < max_n_cpus ; i++) {
+            if (MASK_CPU_ISSET(mask, i)) {
+                if (virNodeCapsFillCPUInfo(i, cpus + ncpus++) < 0) {
+                    topology_failed = true;
+                    virResetLastError();
+                }
+            }
+        }

         if (virCapabilitiesAddHostNUMACell(caps, n, ncpus, cpus) < 0)
             goto cleanup;
-        cpus = NULL;
     }

     ret = 0;

 cleanup:
-    virCapabilitiesClearHostNUMACellCPUTopology(cpus, ncpus);
-    VIR_FREE(cpus);
+    if (topology_failed || ret < 0)
+        virCapabilitiesClearHostNUMACellCPUTopology(cpus, ncpus);
+
+    if (ret < 0)
+        VIR_FREE(cpus);
+
     VIR_FREE(mask);
     VIR_FREE(allonesmask);
     return ret;
-- 
1.8.1.1