mono/utils/mono-proclib-windows-uwp.c

   1 /**
   2  * \file
   3  * UWP proclib support for Mono.
   4  *
   5  * Copyright 2016 Microsoft
   6  * Licensed under the MIT license. See LICENSE file in the project root for full license information.
   7 */
   8 #include <config.h>
   9 #include <glib.h>
  10 #include "mono/utils/mono-compiler.h"
  11
  12 #if G_HAVE_API_SUPPORT(HAVE_UWP_WINAPI_SUPPORT)
  13 #include <windows.h>
  14 #include <mono/utils/mono-proclib.h>
  15
  16 gint32
  17 mono_cpu_usage (MonoCpuUsageState *prev)
  18 {
  19         gint32 cpu_usage = 0;
  20         gint64 cpu_total_time;
  21         gint64 cpu_busy_time;
  22         guint64 idle_time;
  23         guint64 kernel_time;
  24         guint64 user_time;
  25         guint64 current_time;
  26         guint64 creation_time;
  27         guint64 exit_time;
  28
  29         GetSystemTimeAsFileTime ((FILETIME*)&current_time);
  30         if (!GetProcessTimes (GetCurrentProcess (), (FILETIME*)&creation_time, (FILETIME*)&exit_time, (FILETIME*)&kernel_time, (FILETIME*)&user_time)) {
  31                 g_error ("GetProcessTimes() failed, error code is %d\n", GetLastError ());
  32                 return -1;
  33         }
  34
  35         // GetProcessTimes user_time is a sum of user time spend by all threads in the process.
  36         // This means that the total user time can be more than real time. In order to adjust for this
  37         // the total available time that we can be scheduled depends on the number of available cores.
  38         // For example, having 2 threads running 100% on a 2 core system for 100 ms will return a user_time of 200ms
  39         // but the current_time - creation_time will only be 100ms but by adjusting the available time based on number of
  40         // of availalbe cores will gives use the total load of the process.
  41         guint64 total_available_time = (current_time - creation_time) * mono_cpu_count ();
  42
  43         idle_time = total_available_time - (kernel_time + user_time);
  44
  45         cpu_total_time = (gint64)((idle_time - (prev ? prev->idle_time : 0)) + (user_time - (prev ? prev->user_time : 0)) + (kernel_time - (prev ? prev->kernel_time : 0)));
  46         cpu_busy_time = (gint64)(cpu_total_time - (idle_time - (prev ? prev->idle_time : 0)));
  47
  48         if (prev) {
  49                 prev->idle_time = idle_time;
  50                 prev->kernel_time = kernel_time;
  51                 prev->user_time = user_time;
  52         }
  53
  54         if (cpu_total_time > 0 && cpu_busy_time > 0)
  55                 cpu_usage = (gint32)(cpu_busy_time * 100 / cpu_total_time);
  56
  57         return cpu_usage;
  58 }
  59
  60 #else /* G_HAVE_API_SUPPORT(HAVE_UWP_WINAPI_SUPPORT) */
  61
  62 MONO_EMPTY_SOURCE_FILE (mono_proclib_windows_uwp);
  63 #endif /* G_HAVE_API_SUPPORT(HAVE_UWP_WINAPI_SUPPORT) */