Changeset 22236 in vbox for trunk/src/VBox/HostDrivers/Support/SUPDrv.c

Timestamp:

Aug 13, 2009 1:39:07 PM (15 years ago)

Author:

vboxsync

Message:

Grab TSC as quickly as possible; minor accuracy improvement

File:

• trunk/src/VBox/HostDrivers/Support/SUPDrv.c (modified) (9 diffs)

trunk/src/VBox/HostDrivers/Support/SUPDrv.c

@@ -4959 +4959 @@
     RTCCUINTREG     fOldFlags = ASMIntDisableFlags(); /* No interruptions please (real problem on S10). */
     PSUPDRVDEVEXT   pDevExt   = (PSUPDRVDEVEXT)pvUser;
-
-    supdrvGipUpdate(pDevExt->pGip, RTTimeSystemNanoTS());
+    uint64_t        u64TSC    = ASMReadTSC();
+    uint64_t        NanoTS    = RTTimeSystemNanoTS();
+
+    supdrvGipUpdate(pDevExt->pGip, NanoTS, u64TSC);
 
     ASMSetFlags(fOldFlags);
@@ -4976 +4978 @@
     PSUPDRVDEVEXT   pDevExt   = (PSUPDRVDEVEXT)pvUser;
     RTCPUID         idCpu     = RTMpCpuId();
+    uint64_t        u64TSC    = ASMReadTSC();
     uint64_t        NanoTS    = RTTimeSystemNanoTS();
 
     /** @todo reset the transaction number and whatnot when iTick == 1. */
     if (pDevExt->idGipMaster == idCpu)
-        supdrvGipUpdate(pDevExt->pGip, NanoTS);
+        supdrvGipUpdate(pDevExt->pGip, NanoTS, u64TSC);
     else
-        supdrvGipUpdatePerCpu(pDevExt->pGip, NanoTS, ASMGetApicId());
+        supdrvGipUpdatePerCpu(pDevExt->pGip, NanoTS, u64TSC, ASMGetApicId());
 
     ASMSetFlags(fOldFlags);
@@ -5278 +5281 @@
  * @param   pGipCpu         Pointer to the per cpu data.
  * @param   u64NanoTS       The current time stamp.
- */
-static void supdrvGipDoUpdateCpu(PSUPGLOBALINFOPAGE pGip, PSUPGIPCPU pGipCpu, uint64_t u64NanoTS)
-{
-    uint64_t    u64TSC;
+ * @param   u64TSC          The current TSC.
+ */
+static void supdrvGipDoUpdateCpu(PSUPGLOBALINFOPAGE pGip, PSUPGIPCPU pGipCpu, uint64_t u64NanoTS, uint64_t u64TSC)
+{
     uint64_t    u64TSCDelta;
     uint32_t    u32UpdateIntervalTSC;
@@ -5288 +5291 @@
     uint64_t    u64CpuHz;
 
+    /* Delta between this and the previous update. */
+    pGipCpu->u32UpdateIntervalNS = (uint32_t)(u64NanoTS - pGipCpu->u64NanoTS);
+
     /*
      * Update the NanoTS.
@@ -5297 +5303 @@
      */
     /** @todo validate the NanoTS delta, don't trust the OS to call us when it should... */
-    u64TSC = ASMReadTSC();
     u64TSCDelta = u64TSC - pGipCpu->u64TSC;
     ASMAtomicXchgU64(&pGipCpu->u64TSC, u64TSC);
@@ -5369 +5374 @@
  * @param   pGip        Pointer to the GIP.
  * @param   u64NanoTS   The current nanosecond timesamp.
- */
-void VBOXCALL supdrvGipUpdate(PSUPGLOBALINFOPAGE pGip, uint64_t u64NanoTS)
+ * @param   u64TSC      The current TSC timesamp.
+ */
+void VBOXCALL supdrvGipUpdate(PSUPGLOBALINFOPAGE pGip, uint64_t u64NanoTS, uint64_t u64TSC)
 {
     /*
@@ -5421 +5427 @@
      * Update the data.
      */
-    supdrvGipDoUpdateCpu(pGip, pGipCpu, u64NanoTS);
+    supdrvGipDoUpdateCpu(pGip, pGipCpu, u64NanoTS, u64TSC);
 
     /*
@@ -5435 +5441 @@
  * @param   pGip        Pointer to the GIP.
  * @param   u64NanoTS   The current nanosecond timesamp.
+ * @param   u64TSC      The current TSC timesamp.
  * @param   iCpu        The CPU index.
  */
-void VBOXCALL supdrvGipUpdatePerCpu(PSUPGLOBALINFOPAGE pGip, uint64_t u64NanoTS, unsigned iCpu)
+void VBOXCALL supdrvGipUpdatePerCpu(PSUPGLOBALINFOPAGE pGip, uint64_t u64NanoTS, uint64_t u64TSC, unsigned iCpu)
 {
     PSUPGIPCPU  pGipCpu;
@@ -5459 +5466 @@
          * Update the data.
          */
-        supdrvGipDoUpdateCpu(pGip, pGipCpu, u64NanoTS);
+        supdrvGipDoUpdateCpu(pGip, pGipCpu, u64NanoTS, u64TSC);
 
         /*