[libvirt] [PATCH 6/7] shared_memory: Expose the APIs to virsh

[Osier Yang]

New command node-shared-memory-tune to get/set the node shared
memory parameters, only two parameters are allowed to set
(pages_to_scan, and sleep_millisecs, see documents in this
patch for more details).
---
 tools/virsh-host.c |  110 ++++++++++++++++++++++++++++++++++++++++++++++++++++
 tools/virsh.pod    |    8 ++++
 2 files changed, 118 insertions(+), 0 deletions(-)

diff --git a/tools/virsh-host.c b/tools/virsh-host.c
index c46288b..a33cdd7 100644
--- a/tools/virsh-host.c
+++ b/tools/virsh-host.c
@@ -37,6 +37,7 @@
 #include "util.h"
 #include "virsh-domain.h"
 #include "xml.h"
+#include "virtypedparam.h"
 
 /*
  * "capabilities" command
@@ -884,12 +885,121 @@ cmdVersion(vshControl *ctl, const vshCmd *cmd ATTRIBUTE_UNUSED)
     return true;
 }
 
+static const vshCmdInfo info_node_shared_memory_tune[] = {
+    {"help", N_("Get or set node shared memory parameters")},
+    {"desc", N_("Get or set node shared memory parameters"
+                "    To get the shared memory parameters, use following command: \n\n"
+                "    virsh # node-shared-memory-tune")},
+    {NULL, NULL}
+};
+
+static const vshCmdOptDef opts_node_shared_memory_tune[] = {
+    {"pages-to-scan", VSH_OT_INT, VSH_OFLAG_NONE,
+      N_("number of pages to scan before shared memory service "
+         "goes to sleep")},
+    {"sleep-millisecs", VSH_OT_INT, VSH_OFLAG_NONE,
+      N_("number of millisecs the shared memory service should "
+         "sleep before next scan")},
+    {NULL, 0, 0, NULL}
+};
+
+static bool
+cmdNodeSharedMemoryTune(vshControl *ctl, const vshCmd *cmd)
+{
+    virTypedParameterPtr params = NULL;
+    int nparams = 0;
+    unsigned int flags = 0;
+    unsigned int pages_to_scan = 0;
+    unsigned int sleep_millisecs = 0;
+    bool ret = false;
+    int i = 0;
+
+    if (vshCommandOptUInt(cmd, "pages-to-scan", &pages_to_scan) < 0) {
+        vshError(ctl, "%s", _("invalid pages-to-scan number"));
+        return false;
+    }
+
+    if (vshCommandOptUInt(cmd, "sleep-millisecs", &sleep_millisecs) < 0) {
+        vshError(ctl, "%s", _("invalid sleep-millisecs number"));
+        return false;
+    }
+
+    if (pages_to_scan)
+        nparams++;
+
+    if (sleep_millisecs)
+        nparams++;
+
+    if (nparams == 0) {
+        /* Get the number of shared memory parameters */
+        if (virNodeGetSharedMemoryParameters(ctl->conn, NULL, &nparams, flags) != 0) {
+            vshError(ctl, "%s",
+                     _("Unable to get number of shared memory parameters"));
+            goto cleanup;
+        }
+
+        if (nparams == 0) {
+            ret = true;
+            goto cleanup;
+        }
+
+        /* Now go get all the shared memory parameters */
+        params = vshCalloc(ctl, nparams, sizeof(*params));
+        if (virNodeGetSharedMemoryParameters(ctl->conn, params, &nparams, flags) != 0) {
+            vshError(ctl, "%s", _("Unable to get shared memory parameters"));
+            goto cleanup;
+        }
+
+        for (i = 0; i < nparams; i++) {
+            char *str = vshGetTypedParamValue(ctl, &params[i]);
+            vshPrint(ctl, "%-15s: %s\n", params[i].field, str);
+            VIR_FREE(str);
+        }
+
+        ret = true;
+    } else {
+        /* Set the shared memory parameters */
+        params = vshCalloc(ctl, nparams, sizeof(*params));
+
+        if (i < nparams && pages_to_scan) {
+            if (virTypedParameterAssign(&params[i++],
+                                        VIR_NODE_SHARED_MEMORY_PAGES_TO_SCAN,
+                                        VIR_TYPED_PARAM_UINT,
+                                        pages_to_scan) < 0)
+                goto error;
+        }
+
+        if (i < nparams && sleep_millisecs) {
+            if (virTypedParameterAssign(&params[i++],
+                                        VIR_NODE_SHARED_MEMORY_SLEEP_MILLISECS,
+                                        VIR_TYPED_PARAM_UINT,
+                                        sleep_millisecs) < 0)
+                goto error;
+        }
+
+        if (virNodeSetSharedMemoryParameters(ctl->conn, params, nparams, flags) != 0)
+            goto error;
+        else
+            ret = true;
+    }
+
+cleanup:
+    VIR_FREE(params);
+    return ret;
+
+error:
+    vshError(ctl, "%s", _("Unable to change shared memory parameters"));
+    goto cleanup;
+}
+
 const vshCmdDef hostAndHypervisorCmds[] = {
     {"capabilities", cmdCapabilities, NULL, info_capabilities, 0},
     {"connect", cmdConnect, opts_connect, info_connect,
      VSH_CMD_FLAG_NOCONNECT},
     {"freecell", cmdFreecell, opts_freecell, info_freecell, 0},
     {"hostname", cmdHostname, NULL, info_hostname, 0},
+    {"node-shared-memory-tune", cmdNodeSharedMemoryTune,
+     opts_node_shared_memory_tune, info_node_shared_memory_tune, 0},
     {"nodecpustats", cmdNodeCpuStats, opts_node_cpustats, info_nodecpustats, 0},
     {"nodeinfo", cmdNodeinfo, NULL, info_nodeinfo, 0},
     {"nodememstats", cmdNodeMemStats, opts_node_memstats, info_nodememstats, 0},
diff --git a/tools/virsh.pod b/tools/virsh.pod
index 68138e5..6c9e14e 100644
--- a/tools/virsh.pod
+++ b/tools/virsh.pod
@@ -293,6 +293,14 @@ Real-Time-Clock interrupt to fire (to wake up the node) after a time delay
 specified by the 'duration' parameter. The duration time should be
 at least 60 seconds.
 
+=item B<node-shared-memory-tune> [I<pages-to-scan>] [I<sleep-millisecs>]
+
+Allows you to display or set the node shared memory parameters.
+I<pages-to-scan> can be used to set the number of pages to scan
+before the shared memory service goes to sleep; I<sleep-millisecs>
+can be used to set the number of millisecs the shared memory
+service should sleep before next scan.
+
 =item B<capabilities>
 
 Print an XML document describing the capabilities of the hypervisor
-- 
1.7.7.3