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

Pull request

# gpg: Signature made Mon 12 Jul 2021 17:49:46 BST
# gpg:                using RSA key 8695A8BFD3F97CDAAC35775A9CA4ABB381AB73C8
# gpg: Good signature from "Stefan Hajnoczi <stefanha@redhat.com>" [full]
# gpg:                 aka "Stefan Hajnoczi <stefanha@gmail.com>" [full]
# Primary key fingerprint: 8695 A8BF D3F9 7CDA AC35  775A 9CA4 ABB3 81AB 73C8

* remotes/stefanha-gitlab/tags/tracing-pull-request:
  trace, lttng: require .pc files
  trace/simple: add st_init_group
  trace/simple: pass iter to st_write_event_mapping
  trace: add trace_event_iter_init_group
  trace: iter init tweaks
  qemu-trace-stap: changing SYSTEMTAP_TAPSET considered harmful.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

1 files changed, 31 insertions, 8 deletions

diff --git a/trace/control.c b/trace/control.c
index 4be38e1af2..d5b68e846e 100644
--- a/trace/control.c
+++ b/trace/control.c
@@ -82,6 +82,10 @@ void trace_event_register_group(TraceEvent **events)
     event_groups = g_renew(TraceEventGroup, event_groups, nevent_groups + 1);
     event_groups[nevent_groups].events = events;
     nevent_groups++;
+
+#ifdef CONFIG_TRACE_SIMPLE
+    st_init_group(nevent_groups - 1);
+#endif
 }
 
 
@@ -91,7 +95,7 @@ TraceEvent *trace_event_name(const char *name)
 
     TraceEventIter iter;
     TraceEvent *ev;
-    trace_event_iter_init(&iter, NULL);
+    trace_event_iter_init_all(&iter);
     while ((ev = trace_event_iter_next(&iter)) != NULL) {
         if (strcmp(trace_event_get_name(ev), name) == 0) {
             return ev;
@@ -100,27 +104,46 @@ TraceEvent *trace_event_name(const char *name)
     return NULL;
 }
 
-void trace_event_iter_init(TraceEventIter *iter, const char *pattern)
+void trace_event_iter_init_all(TraceEventIter *iter)
 {
     iter->event = 0;
     iter->group = 0;
+    iter->group_id = -1;
+    iter->pattern = NULL;
+}
+
+void trace_event_iter_init_pattern(TraceEventIter *iter, const char *pattern)
+{
+    trace_event_iter_init_all(iter);
     iter->pattern = pattern;
 }
 
+void trace_event_iter_init_group(TraceEventIter *iter, size_t group_id)
+{
+    trace_event_iter_init_all(iter);
+    iter->group_id = group_id;
+}
+
 TraceEvent *trace_event_iter_next(TraceEventIter *iter)
 {
     while (iter->group < nevent_groups &&
            event_groups[iter->group].events[iter->event] != NULL) {
         TraceEvent *ev = event_groups[iter->group].events[iter->event];
+        size_t group = iter->group;
         iter->event++;
         if (event_groups[iter->group].events[iter->event] == NULL) {
             iter->event = 0;
             iter->group++;
         }
-        if (!iter->pattern ||
-            g_pattern_match_simple(iter->pattern, trace_event_get_name(ev))) {
-            return ev;
+        if (iter->pattern &&
+            !g_pattern_match_simple(iter->pattern, trace_event_get_name(ev))) {
+            continue;
+        }
+        if (iter->group_id != -1 &&
+            iter->group_id != group) {
+            continue;
         }
+        return ev;
     }
 
     return NULL;
@@ -130,7 +153,7 @@ void trace_list_events(FILE *f)
 {
     TraceEventIter iter;
     TraceEvent *ev;
-    trace_event_iter_init(&iter, NULL);
+    trace_event_iter_init_all(&iter);
     while ((ev = trace_event_iter_next(&iter)) != NULL) {
         fprintf(f, "%s\n", trace_event_get_name(ev));
     }
@@ -150,7 +173,7 @@ static void do_trace_enable_events(const char *line_buf)
     TraceEvent *ev;
     bool is_pattern = trace_event_is_pattern(line_ptr);
 
-    trace_event_iter_init(&iter, line_ptr);
+    trace_event_iter_init_pattern(&iter, line_ptr);
     while ((ev = trace_event_iter_next(&iter)) != NULL) {
         if (!trace_event_get_state_static(ev)) {
             if (!is_pattern) {
@@ -256,7 +279,7 @@ void trace_fini_vcpu(CPUState *vcpu)
 
     trace_guest_cpu_exit(vcpu);
 
-    trace_event_iter_init(&iter, NULL);
+    trace_event_iter_init_all(&iter);
     while ((ev = trace_event_iter_next(&iter)) != NULL) {
         if (trace_event_is_vcpu(ev) &&
             trace_event_get_state_static(ev) &&