[libvirt] [PATCHv5 3/6] virNodeGetCPUTimeParameters: Implement public API

[Minoru Usui]

virNodeGetCPUTime: Implement public API

Signed-off-by: Minoru Usui <usui at mxm.nes.nec.co.jp>
---
 src/libvirt.c |   87 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 files changed, 87 insertions(+), 0 deletions(-)

diff --git a/src/libvirt.c b/src/libvirt.c
index 5a5439d..6828e1a 100644
--- a/src/libvirt.c
+++ b/src/libvirt.c
@@ -4930,6 +4930,93 @@ error:
 }
 
 /**
+ * virNodeGetCPUTime:
+ * @conn: a connection object
+ * @params: pointer to node cpu time parameter objects
+ * @nparams: number of node cpu time parameter (this value should be same or
+ *          less than the number of parameters supported)
+ * @flags: currently unused, for future extension. always pass 0.
+ *
+ * This function provides cpu time statistics of the node.
+ * The @params array will be filled with the values equal to the number of
+ * parameters suggested by @nparams
+ *
+ * As the value of @nparams is dynamic, call the API setting @nparams to 0 and
+ * @params as NULL, the API returns the number of parameters supported by the
+ * HV by updating @nparams on SUCCESS. The caller should then allocate @params
+ * array, i.e. (sizeof(@virCPUTimeParameter) * @nparams) bytes and call
+ * the API again.
+ *
+ * Here is the sample code snippet:
+ *
+ * if ((virNodeGetCPUTimeParameters(conn, NULL, &nparams, 0) == 0) &&
+ *     (nparams != 0)) {
+ *     params = vshMalloc(ctl, sizeof(virCPUTimeParameter) * nparams);
+ *     memset(params, 0, sizeof(virCPUTimeParameter) * nparams);
+ *     if (virNodeGetCPUTimeParameters(conn, params, &nparams, 0)) {
+ *         vshError(ctl, "%s", _("Unable to get node cpu time parameters"));
+ *         goto error;
+ *     }
+ * }
+ *
+ * This function requires privileged access to the hypervisor. This function
+ * expects the caller to allocate the @params.
+ *
+ * CPU time Statistics:
+ *
+ * VIR_NODE_CPU_TIME_KERNEL:
+ *     The cumulative CPU time which spends by kernel,
+ *     when the node booting up.(nanoseconds)
+ * VIR_NODE_CPU_TIME_USER:
+ *     The cumulative CPU time which spends by user processes,
+ *     when the node booting up.(nanoseconds)
+ * VIR_NODE_CPU_TIME_IDLE:
+ *     The cumulative idle CPU time, when the node booting up.(nanoseconds)
+ * VIR_NODE_CPU_TIME_IOWAIT:
+ *     The cumulative I/O wait CPU time, when the node booting up.(nanoseconds)
+ * VIR_NODE_CPU_TIME_UTILIZATION:
+ *     The CPU utilization. The usage value is in percent and 100%
+ *     represents all CPUs on the server.
+ *
+ * Returns -1 in case of error, 0 in case of success.
+ */
+int virNodeGetCPUTimeParameters (virConnectPtr conn,
+                                 virCPUTimeParameterPtr params,
+                                 int *nparams, unsigned int flags)
+{
+    VIR_DEBUG("conn=%p, params=%p, nparams=%d, flags=%u",
+              conn, params, (nparams) ? *nparams : -1, flags);
+
+    virResetLastError();
+
+    if (!VIR_IS_CONNECT(conn)) {
+        virLibConnError(VIR_ERR_INVALID_CONN, __FUNCTION__);
+        virDispatchError(NULL);
+        return -1;
+    }
+
+    virCheckFlags(flags, 0);
+
+    if ((nparams == NULL) || (*nparams < 0)) {
+        virLibConnError(VIR_ERR_INVALID_ARG, __FUNCTION__);
+        goto error;
+    }
+
+    if (conn->driver->nodeGetCPUTimeParameters) {
+        int ret;
+        ret = conn->driver->nodeGetCPUTimeParameters (conn, params, nparams, flags);
+        if (ret < 0)
+            goto error;
+        return ret;
+    }
+    virLibConnError(VIR_ERR_NO_SUPPORT, __FUNCTION__);
+
+error:
+    virDispatchError(conn);
+    return -1;
+}
+
+/**
  * virNodeGetFreeMemory:
  * @conn: pointer to the hypervisor connection
  *
-- 
1.7.1