qemu: monitor: Add handlers for 'block-latency-histogram-set'

Add QMP monitor code for setting up latency histogram configuration.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>

src/qemu/qemu_monitor.c

@@ -4569,3 +4569,24 @@ qemuMonitorBlockdevSetActive(qemuMonitor *mon,
 
     return qemuMonitorJSONBlockdevSetActive(mon, nodename, active);
 }
+
+
+int
+qemuMonitorBlockLatencyHistogramSet(qemuMonitor *mon,
+                                    const char *id,
+                                    unsigned int *boundaries,
+                                    unsigned int *boundaries_read,
+                                    unsigned int *boundaries_write,
+                                    unsigned int *boundaries_zone,
+                                    unsigned int *boundaries_flush)
+{
+    QEMU_CHECK_MONITOR(mon);
+    VIR_DEBUG("id='%s'", id);
+
+    return qemuMonitorJSONBlockLatencyHistogramSet(mon, id,
+                                                   boundaries,
+                                                   boundaries_read,
+                                                   boundaries_write,
+                                                   boundaries_zone,
+                                                   boundaries_flush);
+}

src/qemu/qemu_monitor.h

@@ -1985,3 +1985,12 @@ int
 qemuMonitorBlockdevSetActive(qemuMonitor *mon,
                              const char *nodename,
                              bool active);
+
+int
+qemuMonitorBlockLatencyHistogramSet(qemuMonitor *mon,
+                                    const char *id,
+                                    unsigned int *boundaries,
+                                    unsigned int *boundaries_read,
+                                    unsigned int *boundaries_write,
+                                    unsigned int *boundaries_zone,
+                                    unsigned int *boundaries_flush);

src/qemu/qemu_monitor_json.c

@@ -9167,3 +9167,63 @@ qemuMonitorJSONBlockdevSetActive(qemuMonitor *mon,
 
     return qemuMonitorJSONCheckError(cmd, reply);
 }
+
+
+static virJSONValue *
+qemuMonitorJSONBlockLatencyHistogramBoundary(unsigned int *bound)
+{
+    g_autoptr(virJSONValue) ret = virJSONValueNewArray();
+
+    if (!bound)
+        return NULL;
+
+    for (; *bound > 0; bound++) {
+        g_autoptr(virJSONValue) val = virJSONValueNewNumberUint(*bound);
+
+        /* the only error is if the first argument is not an array */
+        ignore_value(virJSONValueArrayAppend(ret, &val));
+    }
+
+    return g_steal_pointer(&ret);
+}
+
+
+int
+qemuMonitorJSONBlockLatencyHistogramSet(qemuMonitor *mon,
+                                        const char *id,
+                                        unsigned int *boundaries,
+                                        unsigned int *boundaries_read,
+                                        unsigned int *boundaries_write,
+                                        unsigned int *boundaries_zone,
+                                        unsigned int *boundaries_flush)
+{
+    g_autoptr(virJSONValue) cmd = NULL;
+    g_autoptr(virJSONValue) reply = NULL;
+
+    g_autoptr(virJSONValue) bound = NULL;
+    g_autoptr(virJSONValue) bound_read = NULL;
+    g_autoptr(virJSONValue) bound_write = NULL;
+    g_autoptr(virJSONValue) bound_zone = NULL;
+    g_autoptr(virJSONValue) bound_flush = NULL;
+
+    bound = qemuMonitorJSONBlockLatencyHistogramBoundary(boundaries);
+    bound_read = qemuMonitorJSONBlockLatencyHistogramBoundary(boundaries_read);
+    bound_write = qemuMonitorJSONBlockLatencyHistogramBoundary(boundaries_write);
+    bound_zone = qemuMonitorJSONBlockLatencyHistogramBoundary(boundaries_zone);
+    bound_flush = qemuMonitorJSONBlockLatencyHistogramBoundary(boundaries_flush);
+
+    if (!(cmd = qemuMonitorJSONMakeCommand("block-latency-histogram-set",
+                                           "s:id", id,
+                                           "A:boundaries", &bound,
+                                           "A:boundaries-read", &bound_read,
+                                           "A:boundaries-write", &bound_write,
+                                           "A:boundaries-zap", &bound_zone,
+                                           "A:boundaries-flush", &bound_flush,
+                                           NULL)))
+        return -1;
+
+    if (qemuMonitorJSONCommand(mon, cmd, &reply) < 0)
+        return -1;
+
+    return qemuMonitorJSONCheckError(cmd, reply);
+}

src/qemu/qemu_monitor_json.h

@@ -818,3 +818,12 @@ int
 qemuMonitorJSONBlockdevSetActive(qemuMonitor *mon,
                                  const char *nodename,
                                  bool active);
+
+int
+qemuMonitorJSONBlockLatencyHistogramSet(qemuMonitor *mon,
+                                        const char *id,
+                                        unsigned int *boundaries,
+                                        unsigned int *boundaries_read,
+                                        unsigned int *boundaries_write,
+                                        unsigned int *boundaries_zone,
+                                        unsigned int *boundaries_flush);

tests/qemumonitorjsontest.c

@@ -1130,6 +1130,14 @@ GEN_TEST_FUNC(qemuMonitorJSONSetAction,
 GEN_TEST_FUNC(qemuMonitorJSONSetLaunchSecurityState, "sev_secret_header",
               "sev_secret", 0, true)
 
+unsigned int testHistogramBoundaries[] = {10, 30, 50, 0};
+GEN_TEST_FUNC(qemuMonitorJSONBlockLatencyHistogramSet, "devid",
+              testHistogramBoundaries,
+              testHistogramBoundaries,
+              testHistogramBoundaries,
+              testHistogramBoundaries,
+              testHistogramBoundaries)
+
 static int
 testQemuMonitorJSONqemuMonitorJSONNBDServerStart(const void *opaque)
 {
@@ -2971,6 +2979,7 @@ mymain(void)
     DO_TEST_GEN(qemuMonitorJSONBlockJobCancel);
     DO_TEST_GEN(qemuMonitorJSONSetAction);
     DO_TEST_GEN(qemuMonitorJSONSetLaunchSecurityState);
+    DO_TEST_GEN(qemuMonitorJSONBlockLatencyHistogramSet);
     DO_TEST(qemuMonitorJSONGetBalloonInfo);
     DO_TEST(qemuMonitorJSONGetBlockInfo);
     DO_TEST(qemuMonitorJSONGetAllBlockStatsInfo);