Review comments

src/core/ext/client_channel/client_channel.c

@@ -755,7 +755,7 @@ static void subchannel_ready_locked(grpc_exec_ctx *exec_ctx, void *arg,
   } else {
     /* Create call on subchannel. */
     grpc_subchannel_call *subchannel_call = NULL;
-    grpc_connected_subchannel_call_args call_args = {
+    const grpc_connected_subchannel_call_args call_args = {
         .pollent = calld->pollent,
         .path = calld->path,
         .start_time = calld->call_start_time,
@@ -988,7 +988,7 @@ static void start_transport_stream_op_locked_inner(grpc_exec_ctx *exec_ctx,
   if (calld->creation_phase == GRPC_SUBCHANNEL_CALL_HOLDER_NOT_CREATING &&
       calld->connected_subchannel != NULL) {
     grpc_subchannel_call *subchannel_call = NULL;
-    grpc_connected_subchannel_call_args call_args = {
+    const grpc_connected_subchannel_call_args call_args = {
         .pollent = calld->pollent,
         .path = calld->path,
         .start_time = calld->call_start_time,

src/core/ext/client_channel/subchannel.c

@@ -778,7 +778,7 @@ grpc_error *grpc_connected_subchannel_create_call(
       args->arena, sizeof(grpc_subchannel_call) + chanstk->call_stack_size);
   grpc_call_stack *callstk = SUBCHANNEL_CALL_TO_CALL_STACK(*call);
   (*call)->connection = con;  // Ref is added below.
-  grpc_call_element_args call_args = {.call_stack = callstk,
+  const grpc_call_element_args call_args = {.call_stack = callstk,
                                             .server_transport_data = NULL,
                                             .context = NULL,
                                             .path = args->path,

src/core/ext/transport/chttp2/transport/incoming_metadata.c

@@ -42,8 +42,8 @@
 
 void grpc_chttp2_incoming_metadata_buffer_init(
     grpc_chttp2_incoming_metadata_buffer *buffer, gpr_arena *arena) {
-  grpc_metadata_batch_init(&buffer->batch);
   buffer->arena = arena;
+  grpc_metadata_batch_init(&buffer->batch);
   buffer->batch.deadline = gpr_inf_future(GPR_CLOCK_REALTIME);
 }
 

src/core/lib/support/arena.c

@@ -53,7 +53,6 @@ struct gpr_arena {
 
 gpr_arena *gpr_arena_create(size_t initial_size) {
   initial_size = ROUND_UP_TO_ALIGNMENT_SIZE(initial_size);
-  gpr_log(GPR_DEBUG, "arena create: %" PRIdPTR, initial_size);
   gpr_arena *a = gpr_zalloc(sizeof(gpr_arena) + initial_size);
   a->initial_zone.size_end = initial_size;
   return a;

test/core/channel/channel_stack_test.c

@@ -139,7 +139,7 @@ static void test_create_channel_stack(void) {
   GPR_ASSERT(*channel_data == 0);
 
   call_stack = gpr_malloc(channel_stack->call_stack_size);
-  grpc_call_element_args args = {
+  const grpc_call_element_args args = {
       .call_stack = call_stack,
       .server_transport_data = NULL,
       .context = NULL,