Add counters for mutex acquisitions, expose in bm_fullstack
diff --git a/build.yaml b/build.yaml
index 456db28..a13ba05 100644
--- a/build.yaml
+++ b/build.yaml
@@ -3825,6 +3825,9 @@
   basicprof:
     CPPFLAGS: -O2 -DGRPC_BASIC_PROFILER -DGRPC_TIMERS_RDTSC
     DEFINES: NDEBUG
+  counters:
+    CPPFLAGS: -O2 -DGPR_MU_COUNTERS
+    DEFINES: NDEBUG
   dbg:
     CPPFLAGS: -O0
     DEFINES: _DEBUG DEBUG