Metrics : Read current CPU frequency

shepherd/shepherd_sniff.c

@@ -5,6 +5,7 @@
 #include "esp_flash_encrypt.h"
 #include "esp_freertos_hooks.h"
 #include "esp_mac.h"
+#include "esp_private/esp_clk.h"
 #include "esp_wifi.h"
 #include "freertos/FreeRTOS.h"
 #include "freertos/task.h"
@@ -63,6 +64,9 @@ static void shepherd_task(void *args) {
     // get memory usage
     printf("Memory usage : %d bytes \n",
            (2048 - uxTaskGetStackHighWaterMark(NULL)));
+    // Get cpu clock frequency
+    // convert return value into MHz
+    printf("Current CPU frequency : %d MHz\n", (esp_clk_cpu_freq() / 1000000));
   }
   vTaskDelete(NULL);
 }