intel: use json for parsing intel_gpu_top output

meson.build

@@ -277,9 +277,9 @@ endif
 
 if get_option('mangoapp') or get_option('mangoapp_layer')
   glfw3_dep = dependency('glfw3')
-  json_dep = dependency('nlohmann_json')
 endif
 
+json_dep = dependency('nlohmann_json')
 subdir('src')
 
 if get_option('include_doc')

src/intel.cpp

@@ -2,38 +2,51 @@
 #include "overlay.h"
 #include "gpu.h"
 #include "spdlog/spdlog.h"
+#include <nlohmann/json.hpp>
+using json = nlohmann::json;
 
 static bool init_intel = false;
 struct gpuInfo gpu_info_intel {};
+
 void intelGpuThread(){
     init_intel = true;
     static char stdout_buffer[1024];
-    FILE* intel_gpu_top = popen("intel_gpu_top -l -s 500", "r");
+    FILE* intel_gpu_top = popen("intel_gpu_top -J -s 500", "r");
+    int num_line = 0;
+    std::string buf;
+    int num_iterations = 0;
     while (fgets(stdout_buffer, sizeof(stdout_buffer), intel_gpu_top)) {
-        if (strstr(stdout_buffer, "Freq") == NULL &&
-            strstr(stdout_buffer, "req") == NULL) {
-        char * pch;
-        pch = strtok(stdout_buffer, " ");
-        int i = 0;
-        while (pch != NULL){
-            switch (i){
-            case 0:
-                gpu_info_intel.CoreClock = atoi(pch);
-                break;
-            case 4:
-                gpu_info_intel.powerUsage = atof(pch);
-                break;
-            case 5:
-                gpu_info_intel.apu_cpu_power = atof(pch);
-                break;
-            case 8:
-                gpu_info_intel.load = atoi(pch);
-                break;
+        if (num_line > 0)
+            buf += stdout_buffer;
+
+        num_line++;
+        if (strlen(stdout_buffer) < 4 && !strchr(stdout_buffer, '{') && !strchr(stdout_buffer, ',')) {
+            if (buf[0] != '{')
+                buf = "{\n" + buf;
+
+            if (num_iterations > 0){
+                buf += "\n}";
+                json j = json::parse(buf);
+                if  (j.contains("engines"))
+                    if (j["engines"].contains("Render/3D/0"))
+                        if (j["engines"]["Render/3D/0"].contains("busy"))
+                            gpu_info_intel.load = j["engines"]["Render/3D/0"]["busy"].get<int>();
+
+                if (j.contains("frequency"))
+                    if (j["frequency"].contains("actual"))
+                        gpu_info_intel.CoreClock = j["frequency"]["actual"].get<int>();
+                if (j.contains("power")){
+                    if (j["power"].contains("GPU"))
+                        gpu_info_intel.powerUsage = j["power"]["GPU"].get<float>();
+                    if (j["power"].contains("Package"))
+                        gpu_info_intel.apu_cpu_power = j["power"]["Package"].get<float>();
+                }
+
             }
-            pch = strtok(NULL, " ");
-            i++;
-        }
+            buf = "";
+            num_line = 0;
         }
+        num_iterations++;
     }
 
     int exitcode = pclose(intel_gpu_top) / 256;

src/meson.build

@@ -186,7 +186,8 @@ vklayer_mesa_overlay = shared_library(
     dep_rt,
     dep_pthread,
     dep_vulkan,
-    windows_deps],
+    windows_deps,
+    json_dep],
   include_directories : [inc_common],
   link_args : link_args,
   install_dir : libdir_mangohud,