Changeset 89827 in vbox

Timestamp:

Jun 22, 2021 9:01:04 AM (4 years ago)

Author:

vboxsync

Message:

Runtime: Make use of CreateWaitableTimerEx and CREATE_WAITABLE_TIMER_HIGH_RESOLUTION available on newer Windwos 10 release to improve timer accuracy for sub tick intervals

Location:

trunk/src/VBox/Runtime/r3/win

Files:

• init-win.cpp (modified) (2 diffs)
• internal-r3-win.h (modified) (1 diff)
• timer-win.cpp (modified) (5 diffs)

trunk/src/VBox/Runtime/r3/win/init-win.cpp

@@ -77 +77 @@
 /** SystemTimeToTzSpecificLocalTime. */
 DECL_HIDDEN_DATA(decltype(SystemTimeToTzSpecificLocalTime) *) g_pfnSystemTimeToTzSpecificLocalTime = NULL;
+/** CreateWaitableTimerEx . */
+DECL_HIDDEN_DATA(PFNCREATEWAITABLETIMEREX)      g_pfnCreateWaitableTimerExW = NULL;
 
 /** The native ntdll.dll handle. */
@@ -513 +515 @@
         g_pfnGetSystemWindowsDirectoryW = (PFNGETWINSYSDIR)GetProcAddress(g_hModKernel32, "GetWindowsDirectoryW");
     g_pfnSystemTimeToTzSpecificLocalTime = (decltype(SystemTimeToTzSpecificLocalTime) *)GetProcAddress(g_hModKernel32, "SystemTimeToTzSpecificLocalTime");
+    g_pfnCreateWaitableTimerExW = (PFNCREATEWAITABLETIMEREX)GetProcAddress(g_hModKernel32, "CreateWaitableTimerExW");
 
     /*

trunk/src/VBox/Runtime/r3/win/internal-r3-win.h

@@ -105 +105 @@
 extern DECL_HIDDEN_DATA(PFNGETWINSYSDIR)                g_pfnGetSystemWindowsDirectoryW;
 extern DECL_HIDDEN_DATA(decltype(SystemTimeToTzSpecificLocalTime) *) g_pfnSystemTimeToTzSpecificLocalTime;
+typedef HANDLE (WINAPI *PFNCREATEWAITABLETIMEREX)(LPSECURITY_ATTRIBUTES, LPCWSTR, DWORD, DWORD);
+extern DECL_HIDDEN_DATA(PFNCREATEWAITABLETIMEREX)       g_pfnCreateWaitableTimerExW;
 
 extern DECL_HIDDEN_DATA(HMODULE)                        g_hModNtDll;

trunk/src/VBox/Runtime/r3/win/timer-win.cpp

@@ -45 +45 @@
 #include <iprt/err.h>
 #include "internal/magics.h"
+#include "internal-r3-win.h"
+
+
+/** Define the flag for creating a manual reset timer if not available in the SDK we are compiling with. */
+#ifndef CREATE_WAITABLE_TIMER_MANUAL_RESET
+# define CREATE_WAITABLE_TIMER_MANUAL_RESET    0x00000001
+#endif
+/** Define the flag for high resolution timers, available since Windows 10 RS4 if not available. */
+#ifndef CREATE_WAITABLE_TIMER_HIGH_RESOLUTION
+# define CREATE_WAITABLE_TIMER_HIGH_RESOLUTION 0x00000002
+#endif
+
 
 RT_C_DECLS_BEGIN
@@ -228 +240 @@
 
 
-RTDECL(int) RTTimerCreateEx(PRTTIMER *ppTimer, uint64_t u64NanoInterval, uint32_t fFlags, PFNRTTIMER pfnTimer, void *pvUser)
-{
-    /*
-     * We don't support the fancy MP features.
-     */
-    if (fFlags & RTTIMER_FLAGS_CPU_SPECIFIC)
-        return VERR_NOT_SUPPORTED;
-
+/**
+ * Tries to set the NT timer resolution to a value matching the given timer interval.
+ *
+ * @returns IPRT status code.
+ * @param   u64NanoInterval             The timer interval in nano seconds.
+ */
+static int rtTimerNtSetTimerResolution(uint64_t u64NanoInterval)
+{
     /*
      * On windows we'll have to set the timer resolution before
@@ -266 +278 @@
     }
 
+    return VINF_SUCCESS;
+}
+
+
+RTDECL(int) RTTimerCreateEx(PRTTIMER *ppTimer, uint64_t u64NanoInterval, uint32_t fFlags, PFNRTTIMER pfnTimer, void *pvUser)
+{
+    /*
+     * We don't support the fancy MP features.
+     */
+    if (fFlags & RTTIMER_FLAGS_CPU_SPECIFIC)
+        return VERR_NOT_SUPPORTED;
+
     /*
      * Create new timer.
@@ -286 +310 @@
         {
             /*
-             * Create Win32 event semaphore.
+             * Create Win32 waitable timer.
+             * We will first try the undocumented CREATE_WAITABLE_TIMER_HIGH_RESOLUTION which
+             * exists since some Windows 10 version (RS4). If this fails we resort to the old
+             * method of setting the timer resolution before creating a timer which will probably
+             * not give us the accuracy for intervals below the system tick resolution.
              */
             pTimer->iError = 0;
-            pTimer->hTimer = CreateWaitableTimer(NULL, TRUE, NULL);
+            if (g_pfnCreateWaitableTimerExW)
+                pTimer->hTimer = g_pfnCreateWaitableTimerExW(NULL, NULL,
+                                                             CREATE_WAITABLE_TIMER_MANUAL_RESET | CREATE_WAITABLE_TIMER_HIGH_RESOLUTION,
+                                                             TIMER_ALL_ACCESS);
+            if (!pTimer->hTimer)
+            {            
+                rc = rtTimerNtSetTimerResolution(u64NanoInterval);
+                if (RT_SUCCESS(rc))
+                    pTimer->hTimer = CreateWaitableTimer(NULL, TRUE, NULL);
+            }
+
             if (pTimer->hTimer)
             {
@@ -321 +359 @@
                 CloseHandle(pTimer->hTimer);
             }
+            else
+                rc = RTErrConvertFromWin32(GetLastError());
             RTSemEventDestroy(pTimer->Event);
             pTimer->Event = NIL_RTSEMEVENT;