trace: [qmp] Add commands to query and control event tracing state
Signed-off-by: Lluís Vilanova <vilanova@ac.upc.edu>
Message-id: 20140825111957.31112.31733.stgit@fimbulvetr.bsc.es
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
diff --git a/trace/qmp.c b/trace/qmp.c
new file mode 100644
index 0000000..0b19489
--- /dev/null
+++ b/trace/qmp.c
@@ -0,0 +1,75 @@
+/*
+ * QMP commands for tracing events.
+ *
+ * Copyright (C) 2014 Lluís Vilanova <vilanova@ac.upc.edu>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or later.
+ * See the COPYING file in the top-level directory.
+ */
+
+#include "qemu/typedefs.h"
+#include "qmp-commands.h"
+#include "trace/control.h"
+
+
+TraceEventInfoList *qmp_trace_event_get_state(const char *name, Error **errp)
+{
+ TraceEventInfoList *events = NULL;
+ bool found = false;
+ TraceEvent *ev;
+
+ ev = NULL;
+ while ((ev = trace_event_pattern(name, ev)) != NULL) {
+ TraceEventInfoList *elem = g_new(TraceEventInfoList, 1);
+ elem->value = g_new(TraceEventInfo, 1);
+ elem->value->name = g_strdup(trace_event_get_name(ev));
+ if (!trace_event_get_state_static(ev)) {
+ elem->value->state = TRACE_EVENT_STATE_UNAVAILABLE;
+ } else if (!trace_event_get_state_dynamic(ev)) {
+ elem->value->state = TRACE_EVENT_STATE_DISABLED;
+ } else {
+ elem->value->state = TRACE_EVENT_STATE_ENABLED;
+ }
+ elem->next = events;
+ events = elem;
+ found = true;
+ }
+
+ if (!found && !trace_event_is_pattern(name)) {
+ error_setg(errp, "unknown event \"%s\"", name);
+ }
+
+ return events;
+}
+
+void qmp_trace_event_set_state(const char *name, bool enable,
+ bool has_ignore_unavailable,
+ bool ignore_unavailable, Error **errp)
+{
+ bool found = false;
+ TraceEvent *ev;
+
+ /* Check all selected events are dynamic */
+ ev = NULL;
+ while ((ev = trace_event_pattern(name, ev)) != NULL) {
+ found = true;
+ if (!(has_ignore_unavailable && ignore_unavailable) &&
+ !trace_event_get_state_static(ev)) {
+ error_setg(errp, "cannot set dynamic tracing state for \"%s\"",
+ trace_event_get_name(ev));
+ return;
+ }
+ }
+ if (!found && !trace_event_is_pattern(name)) {
+ error_setg(errp, "unknown event \"%s\"", name);
+ return;
+ }
+
+ /* Apply changes */
+ ev = NULL;
+ while ((ev = trace_event_pattern(name, ev)) != NULL) {
+ if (trace_event_get_state_static(ev)) {
+ trace_event_set_state_dynamic(ev, enable);
+ }
+ }
+}