Add tracing instructions in ESP32 README.md

.github/.wordlist.txt

@@ -988,6 +988,7 @@ TLV
 tmp
 tngvndl
 TODO
+tokenized
 toolchain
 toolchains
 topologies

config/esp32/components/chip/component.mk

@@ -136,6 +136,7 @@ ifeq ($(is_debug),false)
 endif
 	if [[ "$(CONFIG_ENABLE_PW_RPC)" = "y" ]]; then                        \
 	  echo "chip_build_pw_rpc_lib = true" >> $(OUTPUT_DIR)/args.gn       ;\
+	  echo "chip_build_pw_trace_lib = true" >> $(OUTPUT_DIR)/args.gn       ;\
 	  echo "remove_default_configs = [\"//third_party/connectedhomeip/third_party/pigweed/repo/pw_build:cpp17\"]" >> $(OUTPUT_DIR)/args.gn		;\
 	  echo "pw_log_BACKEND = \"//third_party/connectedhomeip/third_party/pigweed/repo/pw_log_basic\"" >> $(OUTPUT_DIR)/args.gn     ;\
 	  echo "pw_assert_BACKEND = \"//third_party/connectedhomeip/third_party/pigweed/repo/pw_assert_log\"" >> $(OUTPUT_DIR)/args.gn ;\

examples/all-clusters-app/esp32/README.md

@@ -15,6 +15,7 @@ control.
         -   [Flashing app using script](#flashing-app-using-script)
         -   [Note](#note)
     -   [Using the RPC console](#using-the-rpc-console)
+    -   [Device Tracing](#device-tracing)
 
 ---
 
@@ -295,3 +296,16 @@ From within the console you can then invoke rpcs:
 
     rpcs.chip.rpc.Lighting.Get()
     rpcs.chip.rpc.Lighting.Set(on=True, level=128, color=protos.chip.rpc.LightingColor(hue=5, saturation=5))
+
+## Device Tracing
+
+Device tracing is available to analyze the device performance. To turn on
+tracing, build with RPC enabled. See
+[Using the RPC console](#using-the-rpc-console).
+
+Obtain tracing json file.
+
+```
+    $ ./{PIGWEED_REPO}/pw_trace_tokenized/py/pw_trace_tokenized/get_trace.py -d {PORT} -o {OUTPUT_FILE} \
+    -t {ELF_FILE} {PIGWEED_REPO}/pw_trace_tokenized/pw_trace_protos/trace_rpc.proto
+```

src/trace/BUILD.gn

@@ -18,11 +18,14 @@ declare_args() {
   chip_build_pw_trace_lib = false
 }
 
+config("config") {
+  defines = [ "PW_TRACE_BACKEND_SET" ]
+}
+
 source_set("trace") {
   sources = [ "trace.h" ]
-
   if (chip_build_pw_trace_lib) {
-    cflags = [ "-DPW_TRACE_BACKEND_SET=1" ]
+    public_configs = [ ":config" ]
     public_deps = [ "${dir_pigweed}/pw_trace" ]
   }
 }