gpu_fdinfo: find_fd() every 10 secs instead of once

mass effect 1 creates 2 fds with stats, one at the start of the
game and one after loading screen. mangohud does find_fd() only
once at the start of the game and hence will miss second fd
which has actual gpu stats.

src/gpu_fdinfo.cpp

@@ -1,13 +1,12 @@
 #include "gpu_fdinfo.h"
 #include "hud_elements.h"
+
 namespace fs = ghc::filesystem;
 
 void GPU_fdinfo::find_fd()
 {
-    if (fdinfo.size() > 0) {
-        fdinfo.clear();
-        fdinfo_data.clear();
-    }
+    fdinfo.clear();
+    fdinfo_data.clear();
 
     auto dir = std::string("/proc/") + std::to_string(pid) + "/fdinfo";
     auto path = fs::path(dir);
@@ -497,6 +496,15 @@ void GPU_fdinfo::main_thread()
             find_fd();
         }
 
+        // Recheck fds every 10secs, fixes Mass Effect 1, maybe some others too
+        {
+            auto t = os_time_get_nano() / 1'000'000;
+            if (t - fdinfo_last_update_ms >= 10'000) {
+                find_fd();
+                fdinfo_last_update_ms = t;
+            }
+        }
+
         gather_fdinfo_data();
         get_current_hwmon_readings();
 

src/gpu_fdinfo.h

@@ -1,24 +1,27 @@
 #pragma once
-#include <cstdint>
-#include <filesystem.h>
+
 #include <inttypes.h>
 #include <sys/stat.h>
 #include <sys/types.h>
 #include <unistd.h>
+
+#include <cstdint>
 #include <thread>
+#include <atomic>
+#include <map>
+#include <set>
+#include <regex>
 
 #ifdef TEST_ONLY
 #include <../src/mesa/util/os_time.h>
 #else
 #include "mesa/util/os_time.h"
 #endif
 
-#include "gpu_metrics_util.h"
-#include <atomic>
 #include <spdlog/spdlog.h>
-#include <map>
-#include <set>
-#include <regex>
+#include <filesystem.h>
+
+#include "gpu_metrics_util.h"
 
 struct hwmon_sensor {
     std::regex rx;
@@ -53,6 +56,7 @@ class GPU_fdinfo {
     mutable std::mutex metrics_mutex;
 
     std::vector<std::ifstream> fdinfo;
+    uint64_t fdinfo_last_update_ms = 0;
 
     std::map<std::string, hwmon_sensor> hwmon_sensors;