Changeset 77380 in vbox for trunk/src/VBox/VMM/VMMAll

Timestamp:

Feb 20, 2019 1:40:22 PM (6 years ago)

Author:

vboxsync

svn:sync-xref-src-repo-rev:

128931

Message:

VMM: Further improvments on the IEM timer polling by making it fully configurable. Sideeffect is that EMSTATE_IEM_THEN_REM has now become more accurate and will execute fewer instructions (exactly 1024 rather than up to 1023+4096) before switching to REM.

File:

• trunk/src/VBox/VMM/VMMAll/IEMAll.cpp (modified) (4 diffs)

trunk/src/VBox/VMM/VMMAll/IEMAll.cpp

@@ -14337 +14337 @@
 
 
-VMMDECL(VBOXSTRICTRC) IEMExecLots(PVMCPU pVCpu, uint32_t *pcInstructions)
+VMMDECL(VBOXSTRICTRC) IEMExecLots(PVMCPU pVCpu, uint32_t cMaxInstructions, uint32_t cPollRate, uint32_t *pcInstructions)
 {
     uint32_t const cInstructionsAtStart = pVCpu->iem.s.cInstructions;
+    AssertMsg(RT_IS_POWER_OF_TWO(cPollRate + 1), ("%#x\n", cPollRate));
 
     /*
@@ -14386 +14387 @@
      * Initial decoder init w/ prefetch, then setup setjmp.
      */
-    unsigned     cTimerPoll = 0;
     VBOXSTRICTRC rcStrict = iemInitDecoderAndPrefetchOpcodes(pVCpu, false);
     if (rcStrict == VINF_SUCCESS)
@@ -14401 +14401 @@
              * The run loop.  We limit ourselves to 4096 instructions right now.
              */
-            PVM         pVM    = pVCpu->CTX_SUFF(pVM);
-            uint32_t    cInstr = 4096;
+            PVM pVM = pVCpu->CTX_SUFF(pVM);
             for (;;)
             {
@@ -14442 +14441 @@
                                       && !VM_FF_IS_ANY_SET(pVM, VM_FF_ALL_MASK) ))
                         {
-                            if (cInstr-- > 0)
+                            if (cMaxInstructions-- > 0)
                             {
-                                /* Poll timers every 128 call*/
-                                if (   (++cTimerPoll & 0x7f) != 0
+                                /* Poll timers every 2048 instructions. */
+                                if (   (cMaxInstructions & cPollRate) != 0
                                     || !TMTimerPollBool(pVM, pVCpu))
                                 {