With qemu guest agent 9.3 we are able to get the load averages with a
new command.

Signed-off-by: Martin Kletzander <mkletzan@redhat.com>
---
 src/qemu/qemu_agent.c | 55 +++++++++++++++++++++++++++++++++++++++++++
 src/qemu/qemu_agent.h |  6 +++++
 tests/qemuagenttest.c | 53 +++++++++++++++++++++++++++++++++++++++++
 3 files changed, 114 insertions(+)

diff --git a/src/qemu/qemu_agent.c b/src/qemu/qemu_agent.c
index 43fca86f10ed..27efb4b389ee 100644
--- a/src/qemu/qemu_agent.c
+++ b/src/qemu/qemu_agent.c
@@ -2568,3 +2568,58 @@ int qemuAgentGetDisks(qemuAgent *agent,
     g_free(*disks);
     return -1;
 }
+
+
+int
+qemuAgentGetLoadAvg(qemuAgent *agent,
+                    double *load1m,
+                    double *load5m,
+                    double *load15m,
+                    bool report_unsupported)
+{
+    g_autoptr(virJSONValue) cmd = NULL;
+    g_autoptr(virJSONValue) reply = NULL;
+    virJSONValue *data = NULL;
+    int rc;
+
+    if (load1m)
+        *load1m = 0;
+
+    if (load5m)
+        *load5m = 0;
+
+    if (load15m)
+        *load15m = 0;
+
+    if (!(cmd = qemuAgentMakeCommand("guest-get-load", NULL)))
+        return -1;
+
+    if ((rc = qemuAgentCommandFull(agent, cmd, &reply, agent->timeout,
+                                   report_unsupported)) < 0)
+        return rc;
+
+    if (!(data = virJSONValueObjectGetObject(reply, "return"))) {
+        virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
+                       _("qemu agent didn't return an array of loads"));
+        return -1;
+    }
+
+#define GET_NUMBER_PARAM(param_) \
+    do { \
+        if (param_ && \
+            virJSONValueObjectGetNumberDouble(data, #param_, param_) < 0) { \
+            virReportError(VIR_ERR_INTERNAL_ERROR, \
+                           _("'%1$s' missing in reply of guest-get-load"), \
+                           #param_); \
+            return -1; \
+        } \
+    } while (0)
+
+    GET_NUMBER_PARAM(load1m);
+    GET_NUMBER_PARAM(load5m);
+    GET_NUMBER_PARAM(load15m);
+
+#undef GET_NUMBER_PARAM
+
+    return 0;
+}
diff --git a/src/qemu/qemu_agent.h b/src/qemu/qemu_agent.h
index f98586e8f8ab..cd17a98d3924 100644
--- a/src/qemu/qemu_agent.h
+++ b/src/qemu/qemu_agent.h
@@ -195,3 +195,9 @@ int qemuAgentSSHRemoveAuthorizedKeys(qemuAgent *agent,
 int qemuAgentGetDisks(qemuAgent *mon,
                       qemuAgentDiskInfo ***disks,
                       bool report_unsupported);
+
+int qemuAgentGetLoadAvg(qemuAgent *agent,
+                        double *load1m,
+                        double *load5m,
+                        double *load15m,
+                        bool report_unsupported);
diff --git a/tests/qemuagenttest.c b/tests/qemuagenttest.c
index 328788024197..566571cf1107 100644
--- a/tests/qemuagenttest.c
+++ b/tests/qemuagenttest.c
@@ -1356,6 +1356,58 @@ testQemuAgentTimezone(const void *data)
     virTypedParamsFree(params, nparams);
     return ret;
 }
+
+
+static const char testQemuAgentGetLoadAvgResponse[] =
+    "{"
+    "  \"return\": {"
+    "    \"load15m\": 0.03564453125,"
+    "    \"load5m\": 0.064453125,"
+    "    \"load1m\": 0.00390625"
+    "  }"
+    "}";
+
+static int
+testQemuAgentGetLoadAvg(const void *data)
+{
+    virDomainXMLOption *xmlopt = (virDomainXMLOption *)data;
+    g_autoptr(qemuMonitorTest) test = qemuMonitorTestNewAgent(xmlopt);
+    double load1m = 0;
+    double load5m = 0;
+    double load15m = 0;
+
+    if (!test)
+        return -1;
+
+    if (qemuMonitorTestAddAgentSyncResponse(test) < 0)
+        return -1;
+
+    if (qemuMonitorTestAddItem(test, "guest-get-load",
+                               testQemuAgentGetLoadAvgResponse) < 0)
+        return -1;
+
+    if (qemuAgentGetLoadAvg(qemuMonitorTestGetAgent(test),
+                            &load1m, &load5m, &load15m, true) < 0)
+        return -1;
+
+#define VALIDATE_LOAD(value_, expected_) \
+    do { \
+        if (value_ != expected_) { \
+            virReportError(VIR_ERR_INTERNAL_ERROR, \
+                           "Expected " #value_ " '%.11f', got '%.11f'", \
+                           expected_, value_); \
+            return -1; \
+        } \
+    } while (0)
+
+    VALIDATE_LOAD(load1m, 0.00390625);
+    VALIDATE_LOAD(load5m, 0.064453125);
+    VALIDATE_LOAD(load15m, 0.03564453125);
+
+    return 0;
+}
+
+
 static int
 mymain(void)
 {
@@ -1392,6 +1444,7 @@ mymain(void)
     DO_TEST(Timezone);
     DO_TEST(SSHKeys);
     DO_TEST(GetDisks);
+    DO_TEST(GetLoadAvg);
 
     DO_TEST(Timeout); /* Timeout should always be called last */
 
-- 
2.48.1

On Tue, Feb 25, 2025 at 15:52:30 +0100, Martin Kletzander wrote:
> With qemu guest agent 9.3 we are able to get the load averages with a
> new command.
> 
> Signed-off-by: Martin Kletzander <mkletzan@redhat.com>
> ---
>  src/qemu/qemu_agent.c | 55 +++++++++++++++++++++++++++++++++++++++++++
>  src/qemu/qemu_agent.h |  6 +++++
>  tests/qemuagenttest.c | 53 +++++++++++++++++++++++++++++++++++++++++
>  3 files changed, 114 insertions(+)
> 
> diff --git a/src/qemu/qemu_agent.c b/src/qemu/qemu_agent.c
> index 43fca86f10ed..27efb4b389ee 100644
> --- a/src/qemu/qemu_agent.c
> +++ b/src/qemu/qemu_agent.c
> @@ -2568,3 +2568,58 @@ int qemuAgentGetDisks(qemuAgent *agent,
>      g_free(*disks);
>      return -1;
>  }
> +
> +
> +int
> +qemuAgentGetLoadAvg(qemuAgent *agent,
> +                    double *load1m,
> +                    double *load5m,
> +                    double *load15m,
> +                    bool report_unsupported)
> +{
> +    g_autoptr(virJSONValue) cmd = NULL;
> +    g_autoptr(virJSONValue) reply = NULL;
> +    virJSONValue *data = NULL;
> +    int rc;
> +
> +    if (load1m)
> +        *load1m = 0;
> +
> +    if (load5m)
> +        *load5m = 0;
> +
> +    if (load15m)
> +        *load15m = 0;

Clearing these is pointless ...

> +
> +    if (!(cmd = qemuAgentMakeCommand("guest-get-load", NULL)))
> +        return -1;
> +
> +    if ((rc = qemuAgentCommandFull(agent, cmd, &reply, agent->timeout,
> +                                   report_unsupported)) < 0)
> +        return rc;
> +
> +    if (!(data = virJSONValueObjectGetObject(reply, "return"))) {
> +        virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
> +                       _("qemu agent didn't return an array of loads"));
> +        return -1;
> +    }
> +
> +#define GET_NUMBER_PARAM(param_) \
> +    do { \
> +        if (param_ && \
> +            virJSONValueObjectGetNumberDouble(data, #param_, param_) < 0) { \

... as they are unconditionally overwritten ...

> +            virReportError(VIR_ERR_INTERNAL_ERROR, \
> +                           _("'%1$s' missing in reply of guest-get-load"), \

How about: parameter '%1%s' missing ...

> +                           #param_); \
> +            return -1; \

... or error is returned.

> +        } \
> +    } while (0)
> +
> +    GET_NUMBER_PARAM(load1m);
> +    GET_NUMBER_PARAM(load5m);
> +    GET_NUMBER_PARAM(load15m);