diff --git a/mace/python/tools/operator.jinja2 b/mace/python/tools/operator.jinja2
index 8ef5bbfc54355724e4f79a301564af5cb3cec416..c1cea9a6837f96e5f4a8702d8dd44cf1363860df 100644
--- a/mace/python/tools/operator.jinja2
+++ b/mace/python/tools/operator.jinja2
@@ -64,7 +64,8 @@ namespace {{tag}} {
 {% for i in range(start, end) %}
 
 void CreateOperator{{i}}(mace::OperatorDef *op) {
-  MACE_LATENCY_LOGGER(2, "Create operator {{ net.op[i].name }}");
+  MACE_LATENCY_LOGGER(2, "Create operator",
+    {{ net.op[i].name|default("undefined")|tojson }});
 
   mace::Argument *arg = nullptr;
   op->mutable_arg()->Reserve({{ net.op[i].arg|length }});
diff --git a/mace/python/tools/str2vec_maps.cc.jinja2 b/mace/python/tools/str2vec_maps.cc.jinja2
index d88347172d0dd4f50d382a7c7598723db151f2e1..ebb27b3850ea935ed9125f656d871e5a540e3399 100644
--- a/mace/python/tools/str2vec_maps.cc.jinja2
+++ b/mace/python/tools/str2vec_maps.cc.jinja2
@@ -25,10 +25,10 @@ namespace {{tag}} {
 const std::map<std::string, ClProgramInfo> {{variable_name}} = {
 {% for key, encrypted_code in maps.items() %}
   {
-    "{{key}}", {
+    {{key|tojson}}, {
       {
         {%- for header in encrypted_code['headers'] -%}
-        "{{header}}",
+        {{header|tojson}},
         {%- endfor -%}
       },
       {
diff --git a/tools/python/template/model.jinja2 b/tools/python/template/model.jinja2
index 494b09860c72631aba45f0390c465c7687a69278..68247fd2380d881fa33138b372775c81b185a173 100644
--- a/tools/python/template/model.jinja2
+++ b/tools/python/template/model.jinja2
@@ -134,7 +134,7 @@ void CreateTensors(NetDef *net_def) {
 namespace {{tag}} {
 
 MACE_API const std::shared_ptr<NetDef> CreateNet() {
-  MACE_LATENCY_LOGGER(1, "Create net {{ net.name }}");
+  MACE_LATENCY_LOGGER(1, "Create net ", {{ net.name|default("undefined")|tojson }});
 
   std::shared_ptr<NetDef> net_def(new NetDef());
 
diff --git a/tools/python/template/operator.jinja2 b/tools/python/template/operator.jinja2
index 8ef5bbfc54355724e4f79a301564af5cb3cec416..c899f3f3c085611af557f812fe8094dcbf1c6fbe 100644
--- a/tools/python/template/operator.jinja2
+++ b/tools/python/template/operator.jinja2
@@ -64,7 +64,8 @@ namespace {{tag}} {
 {% for i in range(start, end) %}
 
 void CreateOperator{{i}}(mace::OperatorDef *op) {
-  MACE_LATENCY_LOGGER(2, "Create operator {{ net.op[i].name }}");
+  MACE_LATENCY_LOGGER(2, "Create operator ",
+    {{ net.op[i].name|default("undefined")|tojson }});
 
   mace::Argument *arg = nullptr;
   op->mutable_arg()->Reserve({{ net.op[i].arg|length }});
diff --git a/tools/python/template/tensor_source.jinja2 b/tools/python/template/tensor_source.jinja2
index f281e88a3ab652657101470a602d8794400e7b6c..ccbc55784fe6d0d2acd2d611ade866ae3891ed83 100644
--- a/tools/python/template/tensor_source.jinja2
+++ b/tools/python/template/tensor_source.jinja2
@@ -23,7 +23,8 @@ namespace mace {
 namespace {{tag}} {
 
 void CreateTensor{{tensor_id}}(mace::ConstTensor *const_tensor) {
-  MACE_LATENCY_LOGGER(2, "Create tensor {{ tensor.name }}");
+  MACE_LATENCY_LOGGER(2, "Create tensor ",
+    {{ tensor.name|default("undefined")|tojson }});
   const_tensor->set_name({{ tensor.name|tojson }});
   const_tensor->set_offset({{ tensor.offset }});
   const_tensor->set_data_size({{ tensor.data_size }});