Merge remote-tracking branch 'remotes/kraxel/tags/vga-20210723-pull-request' into...

[mirror_qemu.git] / trace / simple.c

diff --git a/trace/simple.c b/trace/simple.c
index fc7106ec496d7e4d28a65f6582e372ae8d1e4331..ac499edee0d5fb7b19c700525b9b524ca275f3bc 100644 (file)
--- a/trace/simple.c
+++ b/trace/simple.c
@@ -280,14 +280,12 @@ void trace_record_finish(TraceBufferRecord *rec)
     }
 }
 
-static int st_write_event_mapping(void)
+static int st_write_event_mapping(TraceEventIter *iter)
 {
     uint64_t type = TRACE_RECORD_TYPE_MAPPING;
-    TraceEventIter iter;
     TraceEvent *ev;
 
-    trace_event_iter_init(&iter, NULL);
-    while ((ev = trace_event_iter_next(&iter)) != NULL) {
+    while ((ev = trace_event_iter_next(iter)) != NULL) {
         uint64_t id = trace_event_get_id(ev);
         const char *name = trace_event_get_name(ev);
         uint32_t len = strlen(name);
@@ -302,10 +300,18 @@ static int st_write_event_mapping(void)
     return 0;
 }
 
-void st_set_trace_file_enabled(bool enable)
+/**
+ * Enable / disable tracing, return whether it was enabled.
+ *
+ * @enable: enable if %true, else disable.
+ */
+bool st_set_trace_file_enabled(bool enable)
 {
+    TraceEventIter iter;
+    bool was_enabled = trace_fp;
+
     if (enable == !!trace_fp) {
-        return; /* no change */
+        return was_enabled;     /* no change */
     }
 
     /* Halt trace writeout */
@@ -323,14 +329,15 @@ void st_set_trace_file_enabled(bool enable)
 
         trace_fp = fopen(trace_file_name, "wb");
         if (!trace_fp) {
-            return;
+            return was_enabled;
         }
 
+        trace_event_iter_init_all(&iter);
         if (fwrite(&header, sizeof header, 1, trace_fp) != 1 ||
-            st_write_event_mapping() < 0) {
+            st_write_event_mapping(&iter) < 0) {
             fclose(trace_fp);
             trace_fp = NULL;
-            return;
+            return was_enabled;
         }
 
         /* Resume trace writeout */
@@ -340,6 +347,7 @@ void st_set_trace_file_enabled(bool enable)
         fclose(trace_fp);
         trace_fp = NULL;
     }
+    return was_enabled;
 }
 
 /**
@@ -350,7 +358,7 @@ void st_set_trace_file_enabled(bool enable)
  */
 void st_set_trace_file(const char *file)
 {
-    st_set_trace_file_enabled(false);
+    bool saved_enable = st_set_trace_file_enabled(false);
 
     g_free(trace_file_name);
 
@@ -361,7 +369,7 @@ void st_set_trace_file(const char *file)
         trace_file_name = g_strdup_printf("%s", file);
     }
 
-    st_set_trace_file_enabled(true);
+    st_set_trace_file_enabled(saved_enable);
 }
 
 void st_print_trace_file_status(void)
@@ -414,3 +422,15 @@ bool st_init(void)
     atexit(st_flush_trace_buffer);
     return true;
 }
+
+void st_init_group(size_t group)
+{
+    TraceEventIter iter;
+
+    if (!trace_writeout_enabled) {
+        return;
+    }
+
+    trace_event_iter_init_group(&iter, group);
+    st_write_event_mapping(&iter);
+}