trace: remove vcpu_id from the TraceEvent structure

This does involve temporarily stubbing out some helper functions
before we excise the rest of the code.

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Message-id: 20230526165401.574474-4-alex.bennee@linaro.org
Message-Id: <20230524133952.3971948-4-alex.bennee@linaro.org>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>

scripts/tracetool/format/c.py

@@ -32,19 +32,13 @@ def generate(events, backend, group):
         out('uint16_t %s;' % e.api(e.QEMU_DSTATE))
 
     for e in events:
-        if "vcpu" in e.properties:
-            vcpu_id = 0
-        else:
-            vcpu_id = "TRACE_VCPU_EVENT_NONE"
         out('TraceEvent %(event)s = {',
             '    .id = 0,',
-            '    .vcpu_id = %(vcpu_id)s,',
             '    .name = \"%(name)s\",',
             '    .sstate = %(sstate)s,',
             '    .dstate = &%(dstate)s ',
             '};',
             event = e.api(e.QEMU_EVENT),
-            vcpu_id = vcpu_id,
             name = e.name,
             sstate = "TRACE_%s_ENABLED" % e.name.upper(),
             dstate = e.api(e.QEMU_DSTATE))

scripts/tracetool/format/h.py

@@ -74,16 +74,7 @@ def generate(events, backend, group):
 
         out('}')
 
-        # tracer wrapper with checks (per-vCPU tracing)
+        cond = "true"
-        if "vcpu" in e.properties:
-            trace_cpu = next(iter(e.args))[1]
-            cond = "trace_event_get_vcpu_state(%(cpu)s,"\
-                   " TRACE_%(id)s)"\
-                   % dict(
-                       cpu=trace_cpu,
-                       id=e.name.upper())
-        else:
-            cond = "true"
 
         out('',
             'static inline void %(api)s(%(args)s)',

trace/control-internal.h

@@ -27,12 +27,12 @@ static inline uint32_t trace_event_get_id(TraceEvent *ev)
 
 static inline uint32_t trace_event_get_vcpu_id(TraceEvent *ev)
 {
-    return ev->vcpu_id;
+    return 0;
 }
 
 static inline bool trace_event_is_vcpu(TraceEvent *ev)
 {
-    return ev->vcpu_id != TRACE_VCPU_EVENT_NONE;
+    return false;
 }
 
 static inline const char * trace_event_get_name(TraceEvent *ev)

trace/control.c

@@ -68,16 +68,6 @@ void trace_event_register_group(TraceEvent **events)
     size_t i;
     for (i = 0; events[i] != NULL; i++) {
         events[i]->id = next_id++;
-        if (events[i]->vcpu_id == TRACE_VCPU_EVENT_NONE) {
-            continue;
-        }
-
-        if (likely(next_vcpu_id < CPU_TRACE_DSTATE_MAX_EVENTS)) {
-            events[i]->vcpu_id = next_vcpu_id++;
-        } else {
-            warn_report("too many vcpu trace events; dropping '%s'",
-                        events[i]->name);
-        }
     }
     event_groups = g_renew(TraceEventGroup, event_groups, nevent_groups + 1);
     event_groups[nevent_groups].events = events;

trace/event-internal.h

@@ -19,7 +19,6 @@
 /**
  * TraceEvent:
  * @id: Unique event identifier.
- * @vcpu_id: Unique per-vCPU event identifier.
  * @name: Event name.
  * @sstate: Static tracing state.
  * @dstate: Dynamic tracing state
@@ -33,7 +32,6 @@
  */
 typedef struct TraceEvent {
     uint32_t id;
-    uint32_t vcpu_id;
     const char * name;
     const bool sstate;
     uint16_t *dstate;