perfetto: Add simple support for counters

Perfetto can report time varying numberic values (counters) in tracks.

Add some simple functions to use this.

Signed-off-by: Derek Foreman <derek.foreman@collabora.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/28634>

src/util/perf/cpu_trace.h

@@ -35,6 +35,12 @@
          util_perfetto_trace_end();                                          \
    } while (0)
 
+#define _MESA_TRACE_SET_COUNTER(name, value)                                 \
+   do {                                                                      \
+      if (unlikely(util_perfetto_is_tracing_enabled()))                      \
+         util_perfetto_counter_set(name, value);                             \
+   } while (0)
+
 /* NOTE: for now disable atrace for C++ to workaround a ndk bug with ordering
  * between stdatomic.h and atomic.h.  See:
  *
@@ -49,12 +55,14 @@
 #define _MESA_TRACE_END() atrace_end(ATRACE_TAG_GRAPHICS)
 #define _MESA_TRACE_FLOW_BEGIN(name, id)                                     \
    atrace_begin(ATRACE_TAG_GRAPHICS, name)
+#define _MESA_TRACE_SET_COUNTER(name, value)
 
 #else
 
 #define _MESA_TRACE_BEGIN(name)
 #define _MESA_TRACE_END()
 #define _MESA_TRACE_FLOW_BEGIN(name, id)
+#define _MESA_TRACE_SET_COUNTER(name, value)
 
 #endif /* HAVE_PERFETTO */
 
@@ -128,6 +136,7 @@ _mesa_trace_scope_end(UNUSED int *scope)
 #define MESA_TRACE_SCOPE_FLOW(name, id) _MESA_TRACE_SCOPE_FLOW(name, id)
 #define MESA_TRACE_FUNC() _MESA_TRACE_SCOPE(__func__)
 #define MESA_TRACE_FUNC_FLOW(id) _MESA_TRACE_SCOPE_FLOW(__func__, id)
+#define MESA_TRACE_SET_COUNTER(name, value) _MESA_TRACE_SET_COUNTER(name, value)
 
 static inline void
 util_cpu_trace_init()

src/util/perf/u_perfetto.cc

@@ -72,6 +72,12 @@ util_perfetto_trace_begin_flow(const char *fname, uint64_t id)
       [&](perfetto::EventContext ctx) { ctx.event()->set_name(fname); });
 }
 
+void
+util_perfetto_counter_set(const char *name, double value)
+{
+   TRACE_COUNTER(UTIL_PERFETTO_CATEGORY_DEFAULT_STR, name, value);
+}
+
 uint64_t
 util_perfetto_next_id(void)
 {

src/util/perf/u_perfetto.h

@@ -48,6 +48,8 @@ void util_perfetto_trace_end(void);
 
 void util_perfetto_trace_begin_flow(const char *fname, uint64_t id);
 
+void util_perfetto_counter_set(const char *name, double value);
+
 uint64_t util_perfetto_next_id(void);
 
 #else /* HAVE_PERFETTO */
@@ -77,6 +79,10 @@ static inline void util_perfetto_trace_begin_flow(const char *fname, uint64_t id
 {
 }
 
+static inline void util_perfetto_counter_set(const char *name, double value)
+{
+}
+
 static inline uint64_t util_perfetto_next_id(void)
 {
    return 0;