[Qemu-devel] [PATCH 2/3] log: report hmp/qmp command and qmp event

["Denis V. Lunev" <den@openvz.org>]

From: Pavel Butsykin <pbutsykin@virtuozzo.com>

This log would be very welcome for long-term diagnostics of the system
in the production. This log is at least necessary to understand what
has been happened on the system and to identify issues at higher-level
subsystems (libvirt, etc).

Signed-off-by: Pavel Butsykin <pbutsykin@virtuozzo.com>
Signed-off-by: Denis V. Lunev <den@openvz.org>
CC: Markus Armbruster <armbru@redhat.com>
CC: Luiz Capitulino <lcapitulino@redhat.com>
CC: Eric Blake <eblake@redhat.com>
CC: Peter Maydell <peter.maydell@linaro.org>
---
 include/qemu/log.h |  1 +
 monitor.c          | 18 ++++++++++++++++++
 qemu-log.c         |  1 +
 3 files changed, 20 insertions(+)

diff --git a/include/qemu/log.h b/include/qemu/log.h
index 57b8c96..ba86606 100644
--- a/include/qemu/log.h
+++ b/include/qemu/log.h
@@ -41,6 +41,7 @@ static inline bool qemu_log_enabled(void)
 #define LOG_UNIMP          (1 << 10)
 #define LOG_GUEST_ERROR    (1 << 11)
 #define CPU_LOG_MMU        (1 << 12)
+#define LOG_CMD            (1 << 13)
 
 /* Returns true if a bit is set in the current loglevel mask
  */
diff --git a/monitor.c b/monitor.c
index 4f1ba2f..71810bb 100644
--- a/monitor.c
+++ b/monitor.c
@@ -434,6 +434,12 @@ static void monitor_protocol_emitter(Monitor *mon, QObject *data,
     }
 
     monitor_json_emitter(mon, QOBJECT(qmp));
+    if (qemu_loglevel_mask(LOG_CMD)) {
+        QString *output_json = qobject_to_json_pretty(QOBJECT(qmp));
+        qemu_log("qmp response:\n%s\n", output_json->string);
+        QDECREF(output_json);
+    }
+
     QDECREF(qmp);
 }
 
@@ -474,6 +480,11 @@ monitor_qapi_event_queue(QAPIEvent event, QDict *data, Error **errp)
                                        evstate->last,
                                        now);
 
+    if (qemu_loglevel_mask(LOG_CMD)) {
+        QString *output_json = qobject_to_json_pretty(QOBJECT(data));
+        qemu_log("qmp event:\n%s\n", output_json->string);
+        QDECREF(output_json);
+    }
     /* Rate limit of 0 indicates no throttling */
     qemu_mutex_lock(&monitor_lock);
     if (!evstate->rate) {
@@ -2848,6 +2859,8 @@ static void handle_hmp_command(Monitor *mon, const char *cmdline)
     QDict *qdict;
     const mon_cmd_t *cmd;
 
+    qemu_log_mask(LOG_CMD, "hmp request:\n%s\n", cmdline);
+
     cmd = monitor_parse_command(mon, &cmdline, mon->cmd_table);
     if (!cmd) {
         return;
@@ -3823,6 +3836,11 @@ static void handle_qmp_command(JSONMessageParser *parser, QList *tokens)
         goto err_out;
     }
 
+    if (qemu_loglevel_mask(LOG_CMD)) {
+        QString *output_json = output_json = qobject_to_json_pretty(obj);
+        qemu_log("qmp request:\n%s\n", output_json->string);
+        QDECREF(output_json);
+    }
     input = qmp_check_input_obj(obj, &local_err);
     if (!input) {
         qobject_decref(obj);
diff --git a/qemu-log.c b/qemu-log.c
index e6d2b3f..ba7b34c 100644
--- a/qemu-log.c
+++ b/qemu-log.c
@@ -98,6 +98,7 @@ const QEMULogItem qemu_log_items[] = {
     { LOG_GUEST_ERROR, "guest_errors",
       "log when the guest OS does something invalid (eg accessing a\n"
       "non-existent register)" },
+    { LOG_CMD, "cmd", "log the hmp/qmp commands execution" },
     { 0, NULL, NULL },
 };
 
-- 
2.1.4