Merge remote-tracking branch 'remotes/stefanha-gitlab/tags/tracing-pull-request'...

[mirror_qemu.git] / trace / control.c

diff --git a/trace/control.c b/trace/control.c
index b35e512dcebbaa1cdce0d85fb071424e4c56221f..cd04dd4e0c1cd009410c9d1021b9b5cb468ab158 100644 (file)
--- a/trace/control.c
+++ b/trace/control.c
@@ -39,6 +39,7 @@ static TraceEventGroup *event_groups;
 static size_t nevent_groups;
 static uint32_t next_id;
 static uint32_t next_vcpu_id;
+static bool init_trace_on_startup;
 
 QemuOptsList qemu_trace_opts = {
     .name = "trace",
@@ -124,18 +125,18 @@ TraceEvent *trace_event_iter_next(TraceEventIter *iter)
     return NULL;
 }
 
-void trace_list_events(void)
+void trace_list_events(FILE *f)
 {
     TraceEventIter iter;
     TraceEvent *ev;
     trace_event_iter_init(&iter, NULL);
     while ((ev = trace_event_iter_next(&iter)) != NULL) {
-        fprintf(stderr, "%s\n", trace_event_get_name(ev));
+        fprintf(f, "%s\n", trace_event_get_name(ev));
     }
 #ifdef CONFIG_TRACE_DTRACE
-    fprintf(stderr, "This list of names of trace points may be incomplete "
-                    "when using the DTrace/SystemTap backends.\n"
-                    "Run 'qemu-trace-stap list %s' to print the full list.\n",
+    fprintf(f, "This list of names of trace points may be incomplete "
+               "when using the DTrace/SystemTap backends.\n"
+               "Run 'qemu-trace-stap list %s' to print the full list.\n",
             error_get_progname());
 #endif
 }
@@ -175,7 +176,7 @@ static void do_trace_enable_events(const char *line_buf)
 void trace_enable_events(const char *line_buf)
 {
     if (is_help_option(line_buf)) {
-        trace_list_events();
+        trace_list_events(stdout);
         if (monitor_cur() == NULL) {
             exit(0);
         }
@@ -221,11 +222,15 @@ static void trace_init_events(const char *fname)
     loc_pop(&loc);
 }
 
-void trace_init_file(const char *file)
+void trace_init_file(void)
 {
+    QemuOpts *opts = qemu_find_opts_singleton("trace");
+    const char *file = qemu_opt_get(opts, "file");
 #ifdef CONFIG_TRACE_SIMPLE
     st_set_trace_file(file);
-    st_set_trace_file_enabled(true);
+    if (init_trace_on_startup) {
+        st_set_trace_file_enabled(true);
+    }
 #elif defined CONFIG_TRACE_LOG
     /*
      * If both the simple and the log backends are enabled, "--trace file"
@@ -286,9 +291,8 @@ bool trace_init_backends(void)
     return true;
 }
 
-char *trace_opt_parse(const char *optarg)
+void trace_opt_parse(const char *optarg)
 {
-    char *trace_file;
     QemuOpts *opts = qemu_opts_parse_noisily(qemu_find_opts("trace"),
                                              optarg, true);
     if (!opts) {
@@ -298,10 +302,8 @@ char *trace_opt_parse(const char *optarg)
         trace_enable_events(qemu_opt_get(opts, "enable"));
     }
     trace_init_events(qemu_opt_get(opts, "events"));
-    trace_file = g_strdup(qemu_opt_get(opts, "file"));
+    init_trace_on_startup = true;
     qemu_opts_del(opts);
-
-    return trace_file;
 }
 
 uint32_t trace_get_vcpu_event_count(void)