From 200a40f94ec9427eb7187d9d5396ad3a3f2925c8 Mon Sep 17 00:00:00 2001
From: Derbyshev Dmitry <dderbyshev@virtuozzo.com>
Date: Wed, 1 Jun 2016 20:07:07 +0300
Subject: [PATCH] qemu: expand domain memory statistics with 'last-update'
 timestamp

QEMU reports timestamp along with other memory statistics, but this information is not saved into domain statistics.
It could be useful to determine if the data reported is fresh or not.
Balloon statistics are not reported in hrf, so no modifications are made in qemu_monitor_text.c.

Signed-off-by: Derbyshev Dmitry <dderbyshev@virtuozzo.com>
---
 include/libvirt/libvirt-domain.h |  5 ++++-
 src/libvirt-domain.c             |  2 ++
 src/qemu/qemu_monitor_json.c     | 22 ++++++++++++----------
 tools/virsh-domain-monitor.c     |  2 ++
 4 files changed, 20 insertions(+), 11 deletions(-)

diff --git a/include/libvirt/libvirt-domain.h b/include/libvirt/libvirt-domain.h
index 3fb482b306..e0e3739b08 100644
--- a/include/libvirt/libvirt-domain.h
+++ b/include/libvirt/libvirt-domain.h
@@ -609,11 +609,14 @@ typedef enum {
      */
     VIR_DOMAIN_MEMORY_STAT_USABLE          = 8,
 
+    /* Timestamp of the last update of statistics */
+    VIR_DOMAIN_MEMORY_STAT_LAST_UPDATE     = 9,
+
     /*
      * The number of statistics supported by this version of the interface.
      * To add new statistics, add them to the enum and increase this value.
      */
-    VIR_DOMAIN_MEMORY_STAT_NR              = 9,
+    VIR_DOMAIN_MEMORY_STAT_NR              = 10,
 
 # ifdef VIR_ENUM_SENTINELS
     VIR_DOMAIN_MEMORY_STAT_LAST = VIR_DOMAIN_MEMORY_STAT_NR
diff --git a/src/libvirt-domain.c b/src/libvirt-domain.c
index 1467030db7..413f8af5a4 100644
--- a/src/libvirt-domain.c
+++ b/src/libvirt-domain.c
@@ -5991,6 +5991,8 @@ virDomainGetInterfaceParameters(virDomainPtr domain,
  *     to swap, corresponds to 'Available' in /proc/meminfo
  * VIR_DOMAIN_MEMORY_STAT_ACTUAL_BALLOON:
  *     Current balloon value (in kb).
+ * VIR_DOMAIN_MEMORY_STAT_LAST_UPDATE
+ *     Timestamp of the last statistic
  *
  * Returns: The number of stats provided or -1 in case of failure.
  */
diff --git a/src/qemu/qemu_monitor_json.c b/src/qemu/qemu_monitor_json.c
index 7fa984741b..37bab949a1 100644
--- a/src/qemu/qemu_monitor_json.c
+++ b/src/qemu/qemu_monitor_json.c
@@ -1633,10 +1633,10 @@ qemuMonitorJSONGetBalloonInfo(qemuMonitorPtr mon,
  * rates and/or whether data has been collected since a previous cycle.
  * It's currently unused.
  */
-#define GET_BALLOON_STATS(FIELD, TAG, DIVISOR)                                \
-    if (virJSONValueObjectHasKey(statsdata, FIELD) &&                         \
+#define GET_BALLOON_STATS(OBJECT, FIELD, TAG, DIVISOR)                        \
+    if (virJSONValueObjectHasKey(OBJECT, FIELD) &&                            \
        (got < nr_stats)) {                                                    \
-        if (virJSONValueObjectGetNumberUlong(statsdata, FIELD, &mem) < 0) {   \
+        if (virJSONValueObjectGetNumberUlong(OBJECT, FIELD, &mem) < 0) {      \
             VIR_DEBUG("Failed to get '%s' value", FIELD);                     \
         } else {                                                              \
             /* Not being collected? No point in providing bad data */         \
@@ -1707,20 +1707,22 @@ int qemuMonitorJSONGetMemoryStats(qemuMonitorPtr mon,
         goto cleanup;
     }
 
-    GET_BALLOON_STATS("stat-swap-in",
+    GET_BALLOON_STATS(statsdata, "stat-swap-in",
                       VIR_DOMAIN_MEMORY_STAT_SWAP_IN, 1024);
-    GET_BALLOON_STATS("stat-swap-out",
+    GET_BALLOON_STATS(statsdata, "stat-swap-out",
                       VIR_DOMAIN_MEMORY_STAT_SWAP_OUT, 1024);
-    GET_BALLOON_STATS("stat-major-faults",
+    GET_BALLOON_STATS(statsdata, "stat-major-faults",
                       VIR_DOMAIN_MEMORY_STAT_MAJOR_FAULT, 1);
-    GET_BALLOON_STATS("stat-minor-faults",
+    GET_BALLOON_STATS(statsdata, "stat-minor-faults",
                       VIR_DOMAIN_MEMORY_STAT_MINOR_FAULT, 1);
-    GET_BALLOON_STATS("stat-free-memory",
+    GET_BALLOON_STATS(statsdata, "stat-free-memory",
                       VIR_DOMAIN_MEMORY_STAT_UNUSED, 1024);
-    GET_BALLOON_STATS("stat-total-memory",
+    GET_BALLOON_STATS(statsdata, "stat-total-memory",
                       VIR_DOMAIN_MEMORY_STAT_AVAILABLE, 1024);
-    GET_BALLOON_STATS("stat-available-memory",
+    GET_BALLOON_STATS(statsdata, "stat-available-memory",
                       VIR_DOMAIN_MEMORY_STAT_USABLE, 1024);
+    GET_BALLOON_STATS(data, "last-update",
+                      VIR_DOMAIN_MEMORY_STAT_LAST_UPDATE, 1);
     ret = got;
  cleanup:
     virJSONValueFree(cmd);
diff --git a/tools/virsh-domain-monitor.c b/tools/virsh-domain-monitor.c
index 7f30da2188..77aa272265 100644
--- a/tools/virsh-domain-monitor.c
+++ b/tools/virsh-domain-monitor.c
@@ -375,6 +375,8 @@ cmdDomMemStat(vshControl *ctl, const vshCmd *cmd)
             vshPrint(ctl, "actual %llu\n", stats[i].val);
         if (stats[i].tag == VIR_DOMAIN_MEMORY_STAT_RSS)
             vshPrint(ctl, "rss %llu\n", stats[i].val);
+        if (stats[i].tag == VIR_DOMAIN_MEMORY_STAT_LAST_UPDATE)
+            vshPrint(ctl, "last_update %llu\n", stats[i].val);
     }
 
     ret = true;