Add call combiner stats
diff --git a/src/core/lib/debug/stats_data.cc b/src/core/lib/debug/stats_data.cc
index b4ae8f3..2271c87 100644
--- a/src/core/lib/debug/stats_data.cc
+++ b/src/core/lib/debug/stats_data.cc
@@ -104,6 +104,8 @@
     "combiner_locks_scheduled_items",
     "combiner_locks_scheduled_final_items",
     "combiner_locks_offloaded",
+    "call_combiner_locks_initiated",
+    "call_combiner_locks_scheduled_items",
     "executor_scheduled_short_items",
     "executor_scheduled_long_items",
     "executor_scheduled_to_self",
@@ -213,6 +215,9 @@
     "Number of items scheduled against combiner locks",
     "Number of final items scheduled against combiner locks",
     "Number of combiner locks offloaded to different threads",
+    "Number of call combiner lock entries by process (first items queued to a "
+    "call combiner)",
+    "Number of items scheduled against call combiner locks",
     "Number of finite runtime closures scheduled against the executor (gRPC "
     "thread pool)",
     "Number of potentially infinite runtime closures scheduled against the "
diff --git a/src/core/lib/debug/stats_data.h b/src/core/lib/debug/stats_data.h
index d4c4437..bfa5c1a 100644
--- a/src/core/lib/debug/stats_data.h
+++ b/src/core/lib/debug/stats_data.h
@@ -110,6 +110,8 @@
   GRPC_STATS_COUNTER_COMBINER_LOCKS_SCHEDULED_ITEMS,
   GRPC_STATS_COUNTER_COMBINER_LOCKS_SCHEDULED_FINAL_ITEMS,
   GRPC_STATS_COUNTER_COMBINER_LOCKS_OFFLOADED,
+  GRPC_STATS_COUNTER_CALL_COMBINER_LOCKS_INITIATED,
+  GRPC_STATS_COUNTER_CALL_COMBINER_LOCKS_SCHEDULED_ITEMS,
   GRPC_STATS_COUNTER_EXECUTOR_SCHEDULED_SHORT_ITEMS,
   GRPC_STATS_COUNTER_EXECUTOR_SCHEDULED_LONG_ITEMS,
   GRPC_STATS_COUNTER_EXECUTOR_SCHEDULED_TO_SELF,
@@ -407,6 +409,12 @@
 #define GRPC_STATS_INC_COMBINER_LOCKS_OFFLOADED(exec_ctx) \
   GRPC_STATS_INC_COUNTER((exec_ctx),                      \
                          GRPC_STATS_COUNTER_COMBINER_LOCKS_OFFLOADED)
+#define GRPC_STATS_INC_CALL_COMBINER_LOCKS_INITIATED(exec_ctx) \
+  GRPC_STATS_INC_COUNTER((exec_ctx),                           \
+                         GRPC_STATS_COUNTER_CALL_COMBINER_LOCKS_INITIATED)
+#define GRPC_STATS_INC_CALL_COMBINER_LOCKS_SCHEDULED_ITEMS(exec_ctx) \
+  GRPC_STATS_INC_COUNTER(                                            \
+      (exec_ctx), GRPC_STATS_COUNTER_CALL_COMBINER_LOCKS_SCHEDULED_ITEMS)
 #define GRPC_STATS_INC_EXECUTOR_SCHEDULED_SHORT_ITEMS(exec_ctx) \
   GRPC_STATS_INC_COUNTER((exec_ctx),                            \
                          GRPC_STATS_COUNTER_EXECUTOR_SCHEDULED_SHORT_ITEMS)
diff --git a/src/core/lib/debug/stats_data.yaml b/src/core/lib/debug/stats_data.yaml
index 00e81e7..d12c8df 100644
--- a/src/core/lib/debug/stats_data.yaml
+++ b/src/core/lib/debug/stats_data.yaml
@@ -245,6 +245,12 @@
   doc: Number of final items scheduled against combiner locks
 - counter: combiner_locks_offloaded
   doc: Number of combiner locks offloaded to different threads
+# call combiner locks
+- counter: call_combiner_locks_initiated
+  doc: Number of call combiner lock entries by process
+       (first items queued to a call combiner)
+- counter: call_combiner_locks_scheduled_items
+  doc: Number of items scheduled against call combiner locks
 # executor
 - counter: executor_scheduled_short_items
   doc: Number of finite runtime closures scheduled against the executor
@@ -282,4 +288,3 @@
 - counter: cq_ev_queue_transient_pop_failures
   doc: Number of times NULL was popped out of completion queue's event queue
        even though the event queue was not empty
-
diff --git a/src/core/lib/debug/stats_data_bq_schema.sql b/src/core/lib/debug/stats_data_bq_schema.sql
index f34b0c2..5e541b9 100644
--- a/src/core/lib/debug/stats_data_bq_schema.sql
+++ b/src/core/lib/debug/stats_data_bq_schema.sql
@@ -79,6 +79,8 @@
 combiner_locks_scheduled_items_per_iteration:FLOAT,
 combiner_locks_scheduled_final_items_per_iteration:FLOAT,
 combiner_locks_offloaded_per_iteration:FLOAT,
+call_combiner_locks_initiated_per_iteration:FLOAT,
+call_combiner_locks_scheduled_items_per_iteration:FLOAT,
 executor_scheduled_short_items_per_iteration:FLOAT,
 executor_scheduled_long_items_per_iteration:FLOAT,
 executor_scheduled_to_self_per_iteration:FLOAT,
diff --git a/src/core/lib/iomgr/call_combiner.cc b/src/core/lib/iomgr/call_combiner.cc
index bab3df0..8b08d30 100644
--- a/src/core/lib/iomgr/call_combiner.cc
+++ b/src/core/lib/iomgr/call_combiner.cc
@@ -21,6 +21,7 @@
 #include <inttypes.h>
 
 #include <grpc/support/log.h>
+#include "src/core/lib/debug/stats.h"
 
 grpc_tracer_flag grpc_call_combiner_trace =
     GRPC_TRACER_INITIALIZER(false, "call_combiner");
@@ -73,7 +74,9 @@
     gpr_log(GPR_DEBUG, "  size: %" PRIdPTR " -> %" PRIdPTR, prev_size,
             prev_size + 1);
   }
+  GRPC_STATS_INC_CALL_COMBINER_LOCKS_SCHEDULED_ITEMS(exec_ctx);
   if (prev_size == 0) {
+    GRPC_STATS_INC_CALL_COMBINER_LOCKS_INITIATED(exec_ctx);
     if (GRPC_TRACER_ON(grpc_call_combiner_trace)) {
       gpr_log(GPR_DEBUG, "  EXECUTING IMMEDIATELY");
     }
diff --git a/tools/run_tests/performance/massage_qps_stats.py b/tools/run_tests/performance/massage_qps_stats.py
index e0b6ce6..eadd17d 100644
--- a/tools/run_tests/performance/massage_qps_stats.py
+++ b/tools/run_tests/performance/massage_qps_stats.py
@@ -101,6 +101,8 @@
     stats["core_combiner_locks_scheduled_items"] = massage_qps_stats_helpers.counter(core_stats, "combiner_locks_scheduled_items")
     stats["core_combiner_locks_scheduled_final_items"] = massage_qps_stats_helpers.counter(core_stats, "combiner_locks_scheduled_final_items")
     stats["core_combiner_locks_offloaded"] = massage_qps_stats_helpers.counter(core_stats, "combiner_locks_offloaded")
+    stats["core_call_combiner_locks_initiated"] = massage_qps_stats_helpers.counter(core_stats, "call_combiner_locks_initiated")
+    stats["core_call_combiner_locks_scheduled_items"] = massage_qps_stats_helpers.counter(core_stats, "call_combiner_locks_scheduled_items")
     stats["core_executor_scheduled_short_items"] = massage_qps_stats_helpers.counter(core_stats, "executor_scheduled_short_items")
     stats["core_executor_scheduled_long_items"] = massage_qps_stats_helpers.counter(core_stats, "executor_scheduled_long_items")
     stats["core_executor_scheduled_to_self"] = massage_qps_stats_helpers.counter(core_stats, "executor_scheduled_to_self")
diff --git a/tools/run_tests/performance/scenario_result_schema.json b/tools/run_tests/performance/scenario_result_schema.json
index f11e635..1d72653 100644
--- a/tools/run_tests/performance/scenario_result_schema.json
+++ b/tools/run_tests/performance/scenario_result_schema.json
@@ -517,6 +517,16 @@
       }, 
       {
         "mode": "NULLABLE", 
+        "name": "core_call_combiner_locks_initiated", 
+        "type": "INTEGER"
+      }, 
+      {
+        "mode": "NULLABLE", 
+        "name": "core_call_combiner_locks_scheduled_items", 
+        "type": "INTEGER"
+      }, 
+      {
+        "mode": "NULLABLE", 
         "name": "core_executor_scheduled_short_items", 
         "type": "INTEGER"
       }, 
@@ -1329,6 +1339,16 @@
       }, 
       {
         "mode": "NULLABLE", 
+        "name": "core_call_combiner_locks_initiated", 
+        "type": "INTEGER"
+      }, 
+      {
+        "mode": "NULLABLE", 
+        "name": "core_call_combiner_locks_scheduled_items", 
+        "type": "INTEGER"
+      }, 
+      {
+        "mode": "NULLABLE", 
         "name": "core_executor_scheduled_short_items", 
         "type": "INTEGER"
       },