Changeset 59132 in vbox for trunk/src/VBox/VMM

Timestamp:

Dec 15, 2015 12:42:54 PM (9 years ago)

Author:

vboxsync

Message:

VMM: Recursive EMT rendezvous fixes, adding support for recursion from within VMMEMTRENDEZVOUS_FLAGS_TYPE_ONCE callbacks too.

File:

• trunk/src/VBox/VMM/VMMR3/VMM.cpp (modified) (11 diffs)

trunk/src/VBox/VMM/VMMR3/VMM.cpp

@@ -1729 +1729 @@
             if (!fIsCaller)
             {
-                rc = RTSemEventMultiWait(pVM->vmm.s.hEvtMulRendezvousDone, RT_INDEFINITE_WAIT);
-                AssertLogRelRC(rc);
-                Assert(!pVM->vmm.s.fRendezvousRecursion);
+                for (;;)
+                {
+                    rc = RTSemEventMultiWait(pVM->vmm.s.hEvtMulRendezvousDone, RT_INDEFINITE_WAIT);
+                    AssertLogRelRC(rc);
+                    if (!pVM->vmm.s.fRendezvousRecursion)
+                        break;
+                    rcStrictRecursion = vmmR3EmtRendezvousCommonRecursion(pVM, pVCpu, rcStrictRecursion);
+                }
 
                 return vmmR3EmtRendezvousNonCallerReturn(pVM, rcStrictRecursion);
@@ -1764 +1769 @@
                 rc = RTSemEventSignal(pVM->vmm.s.pahEvtRendezvousEnterOrdered[iFirst]);
                 AssertLogRelRC(rc);
-                rc = RTSemEventWait(pVM->vmm.s.pahEvtRendezvousEnterOrdered[pVCpu->idCpu], RT_INDEFINITE_WAIT);
-                AssertLogRelRC(rc);
+                for (;;)
+                {
+                    rc = RTSemEventWait(pVM->vmm.s.pahEvtRendezvousEnterOrdered[pVCpu->idCpu], RT_INDEFINITE_WAIT);
+                    AssertLogRelRC(rc);
+                    if (!pVM->vmm.s.fRendezvousRecursion)
+                        break;
+                    rcStrictRecursion = vmmR3EmtRendezvousCommonRecursion(pVM, pVCpu, rcStrictRecursion);
+                }
             }
         }
@@ -1924 +1935 @@
     AssertReturn(   (fParentFlags & VMMEMTRENDEZVOUS_FLAGS_TYPE_MASK) == VMMEMTRENDEZVOUS_FLAGS_TYPE_ASCENDING
                  || (fParentFlags & VMMEMTRENDEZVOUS_FLAGS_TYPE_MASK) == VMMEMTRENDEZVOUS_FLAGS_TYPE_DESCENDING
-                 || (fParentFlags & VMMEMTRENDEZVOUS_FLAGS_TYPE_MASK) == VMMEMTRENDEZVOUS_FLAGS_TYPE_ONE_BY_ONE,
+                 || (fParentFlags & VMMEMTRENDEZVOUS_FLAGS_TYPE_MASK) == VMMEMTRENDEZVOUS_FLAGS_TYPE_ONE_BY_ONE
+                 || (fParentFlags & VMMEMTRENDEZVOUS_FLAGS_TYPE_MASK) == VMMEMTRENDEZVOUS_FLAGS_TYPE_ONCE,
                  VERR_INTERNAL_ERROR);
     AssertReturn(pVM->vmm.s.cRendezvousEmtsEntered == pVM->cCpus, VERR_INTERNAL_ERROR_2);
@@ -1945 +1957 @@
      */
     ASMAtomicWriteU32(&pVM->vmm.s.cRendezvousEmtsRecursingPush, 0);
-    ASMAtomicWriteU32(&pVM->vmm.s.cRendezvousEmtsRecursingPop, 0);
     ASMAtomicWriteBool(&pVM->vmm.s.fRendezvousRecursion, true);
 
     uint32_t cLeft = pVM->cCpus - (cParentDone + 1U);
-    if ((fFlags & VMMEMTRENDEZVOUS_FLAGS_TYPE_MASK) == VMMEMTRENDEZVOUS_FLAGS_TYPE_ONE_BY_ONE)
+    if ((fParentFlags & VMMEMTRENDEZVOUS_FLAGS_TYPE_MASK) == VMMEMTRENDEZVOUS_FLAGS_TYPE_ONE_BY_ONE)
         while (cLeft-- > 0)
         {
@@ -1955 +1966 @@
             AssertLogRelRC(rc);
         }
-    else if ((fFlags & VMMEMTRENDEZVOUS_FLAGS_TYPE_MASK) == VMMEMTRENDEZVOUS_FLAGS_TYPE_ASCENDING)
+    else if ((fParentFlags & VMMEMTRENDEZVOUS_FLAGS_TYPE_MASK) == VMMEMTRENDEZVOUS_FLAGS_TYPE_ASCENDING)
     {
         Assert(cLeft == pVM->cCpus - (pVCpu->idCpu + 1U));
@@ -1964 +1975 @@
         }
     }
-    else if ((fFlags & VMMEMTRENDEZVOUS_FLAGS_TYPE_MASK) == VMMEMTRENDEZVOUS_FLAGS_TYPE_DESCENDING)
+    else if ((fParentFlags & VMMEMTRENDEZVOUS_FLAGS_TYPE_MASK) == VMMEMTRENDEZVOUS_FLAGS_TYPE_DESCENDING)
     {
         Assert(cLeft == pVCpu->idCpu);
-        for (VMCPUID iCpu = pVCpu->idCpu; iCpu > pVM->cCpus; iCpu--)
+        for (VMCPUID iCpu = pVCpu->idCpu; iCpu > 0; iCpu--)
         {
             rc = RTSemEventSignal(pVM->vmm.s.pahEvtRendezvousEnterOrdered[iCpu - 1U]);
@@ -1974 +1985 @@
     }
     else
-        AssertLogRelFailedReturn(VERR_INTERNAL_ERROR_4);
+        AssertLogRelReturn((fParentFlags & VMMEMTRENDEZVOUS_FLAGS_TYPE_MASK) == VMMEMTRENDEZVOUS_FLAGS_TYPE_ONCE,
+                           VERR_INTERNAL_ERROR_4);
 
     rc = RTSemEventMultiSignal(pVM->vmm.s.hEvtMulRendezvousDone);
@@ -2069 +2081 @@
      * Usher the other EMTs back to their parent recursion routine, waiting
      * for them to all get there before we return (makes sure they've been
-     * scheduled and are in position again - paranoia, shouldn't be needed).
-     */
-    rc = RTSemEventMultiSignal(pVM->vmm.s.hEvtMulRendezvousRecursionPush);
+     * scheduled and are past the pop event sem, see below).
+     */
+    ASMAtomicWriteU32(&pVM->vmm.s.cRendezvousEmtsRecursingPop, 0);
+    rc = RTSemEventMultiSignal(pVM->vmm.s.hEvtMulRendezvousRecursionPop);
     AssertLogRelRC(rc);
 
@@ -2079 +2092 @@
         AssertLogRelRC(rc);
     }
+
+    /*
+     * We must reset the pop semaphore on the way out (doing the pop caller too,
+     * just in case).  The parent may be another recursion.
+     */
+    rc = RTSemEventMultiReset(pVM->vmm.s.hEvtMulRendezvousRecursionPop);    AssertLogRelRC(rc);
+    rc = vmmR3HlpResetEvent(pVM->vmm.s.hEvtRendezvousRecursionPopCaller);   AssertLogRelMsg(rc == VERR_TIMEOUT, ("%Rrc\n", rc));
 
     ASMAtomicDecU32(&pVM->vmm.s.cRendezvousRecursions);
@@ -2135 +2155 @@
          * Shortcut for the single EMT case.
          */
-        AssertLogRelReturn(!pVCpu->vmm.s.fInRendezvous, VERR_DEADLOCK);
-        pVCpu->vmm.s.fInRendezvous = true;
-        rcStrict = pfnRendezvous(pVM, pVCpu, pvUser);
-        pVCpu->vmm.s.fInRendezvous = false;
+        if (!pVCpu->vmm.s.fInRendezvous)
+        {
+            pVCpu->vmm.s.fInRendezvous  = true;
+            pVM->vmm.s.fRendezvousFlags = fFlags;
+            rcStrict = pfnRendezvous(pVM, pVCpu, pvUser);
+            pVCpu->vmm.s.fInRendezvous  = false;
+        }
+        else
+        {
+            /* Recursion. Do the same checks as in the SMP case. */
+            uint32_t fType = pVM->vmm.s.fRendezvousFlags & VMMEMTRENDEZVOUS_FLAGS_TYPE_MASK;
+            AssertLogRelReturn(   !pVCpu->vmm.s.fInRendezvous
+                               || fType == VMMEMTRENDEZVOUS_FLAGS_TYPE_ASCENDING
+                               || fType == VMMEMTRENDEZVOUS_FLAGS_TYPE_DESCENDING
+                               || fType == VMMEMTRENDEZVOUS_FLAGS_TYPE_ONE_BY_ONE
+                               || fType == VMMEMTRENDEZVOUS_FLAGS_TYPE_ONCE
+                               , VERR_DEADLOCK);
+
+            AssertLogRelReturn(pVM->vmm.s.cRendezvousRecursions < 3, VERR_DEADLOCK);
+            pVM->vmm.s.cRendezvousRecursions++;
+            uint32_t const fParentFlags = pVM->vmm.s.fRendezvousFlags;
+            pVM->vmm.s.fRendezvousFlags = fFlags;
+
+            rcStrict = pfnRendezvous(pVM, pVCpu, pvUser);
+
+            pVM->vmm.s.fRendezvousFlags = fParentFlags;
+            pVM->vmm.s.cRendezvousRecursions--;
+        }
     }
     else
@@ -2155 +2199 @@
                     || (pVM->vmm.s.fRendezvousFlags & VMMEMTRENDEZVOUS_FLAGS_TYPE_MASK) == VMMEMTRENDEZVOUS_FLAGS_TYPE_DESCENDING
                     || (pVM->vmm.s.fRendezvousFlags & VMMEMTRENDEZVOUS_FLAGS_TYPE_MASK) == VMMEMTRENDEZVOUS_FLAGS_TYPE_ONE_BY_ONE
+                    || (pVM->vmm.s.fRendezvousFlags & VMMEMTRENDEZVOUS_FLAGS_TYPE_MASK) == VMMEMTRENDEZVOUS_FLAGS_TYPE_ONCE
                        ))
                 return VBOXSTRICTRC_TODO(vmmR3EmtRendezvousRecursive(pVM, pVCpu, fFlags, pfnRendezvous, pvUser));