Changeset 37414 in vbox for trunk/src/VBox/VMM

Timestamp:

Jun 10, 2011 3:53:59 PM (14 years ago)

Author:

vboxsync

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

72213

Message:

TM: Added TMTimerLock, TMTimerUnlock and TMTimerIsLockOwner for locking the virtual sync clock to avoid races.

Location:

trunk/src/VBox/VMM

Files:

• VMMAll/TMAll.cpp (modified) (1 diff)
• VMMR0/VMMR0.def (modified) (2 diffs)
• VMMR3/TM.cpp (modified) (10 diffs)
• VMMRC/VMMRC.def (modified) (2 diffs)

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

@@ -802 +802 @@
 {
     return (PTMTIMERRC)MMHyperCCToRC(pTimer->CTX_SUFF(pVM), pTimer);
+}
+
+
+/**
+ * Locks the timer clock.
+ *
+ * @returns VINF_SUCCESS on success, @a rcBusy if busy, and VERR_NOT_SUPPORTED
+ *          if the clock does not have a lock.
+ * @param   pTimer              The timer which clock lock we wish to take.
+ * @param   rcBusy              What to return in ring-0 and raw-mode context
+ *                              if the lock is busy.
+ *
+ * @remarks Currently only supported on timers using the virtual sync clock.
+ */
+VMMDECL(int) TMTimerLock(PTMTIMER pTimer, int rcBusy)
+{
+    AssertPtr(pTimer);
+    AssertReturn(pTimer->enmClock == TMCLOCK_VIRTUAL_SYNC, VERR_NOT_SUPPORTED);
+    return PDMCritSectEnter(&pTimer->CTX_SUFF(pVM)->tm.s.VirtualSyncLock, rcBusy);
+}
+
+
+/**
+ * Unlocks a timer clock locked by TMTimerLock.
+ *
+ * @param   pTimer              The timer which clock to unlock.
+ */
+VMMDECL(void) TMTimerUnlock(PTMTIMER pTimer)
+{
+    AssertPtr(pTimer);
+    AssertReturnVoid(pTimer->enmClock == TMCLOCK_VIRTUAL_SYNC);
+    PDMCritSectLeave(&pTimer->CTX_SUFF(pVM)->tm.s.VirtualSyncLock);
+}
+
+
+/**
+ * Checks if the current thread owns the timer clock lock.
+ *
+ * @returns @c true if its the owner, @c false if not.
+ * @param   pTimer              The timer handle.
+ */
+VMMDECL(bool) TMTimerIsLockOwner(PTMTIMER pTimer)
+{
+    AssertPtr(pTimer);
+    AssertReturn(pTimer->enmClock == TMCLOCK_VIRTUAL_SYNC, false);
+    return PDMCritSectIsOwner(&pTimer->CTX_SUFF(pVM)->tm.s.VirtualSyncLock);
 }
 

trunk/src/VBox/VMM/VMMR0/VMMR0.def

@@ -50 +50 @@
     TMTimerGetFreq
     TMTimerIsActive
+    TMTimerIsLockOwner
+    TMTimerLock
     TMTimerSet
     TMTimerSetRelative
@@ -57 +59 @@
     TMTimerSetFrequencyHint
     TMTimerStop
+    TMTimerUnlock
     VMMGetSvnRev
     vmmR0LoggerFlush

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

@@ -130 +130 @@
 #include <VBox/vmm/pdmapi.h>
 #include <VBox/vmm/iom.h>
+#include <VBox/vmm/dbgftrace.h>
 #include "TMInternal.h"
 #include <VBox/vmm/vm.h>
@@ -2076 +2077 @@
         STAM_COUNTER_INC(&pVM->tm.s.StatVirtualSyncRunStoppedAlready);
         u64Now = pVM->tm.s.u64VirtualSync;
-#ifdef DEBUG_bird
+#if 0 //def DEBUG_bird
         Assert(u64Now <= pNext->u64Expire);
 #endif
+        if (u64Now > pNext->u64Expire)
+            DBGFTRACE_U64_TAG2(pVM, u64Now - pNext->u64Expire, "stopped after timer expired", pNext->pszDesc);
     }
     else
@@ -2179 +2182 @@
 
             /* advance the clock - don't permit timers to be out of order or armed in the 'past'. */
+            if (pTimer->u64Expire < u64Prev)
+                DBGFTRACE_U64_TAG2(pVM, u64Prev - pTimer->u64Expire, "timer expires in the past", pNext->pszDesc);
 #ifdef DEBUG_bird
 #ifdef VBOX_STRICT
-            AssertMsg(pTimer->u64Expire >= u64Prev, ("%'RU64 < %'RU64 %s\n", pTimer->u64Expire, u64Prev, pTimer->pszDesc));
+            //AssertMsg(pTimer->u64Expire >= u64Prev, ("%'RU64 < %'RU64 %s\n", pTimer->u64Expire, u64Prev, pTimer->pszDesc));
             u64Prev = pTimer->u64Expire;
 #endif
@@ -2190 +2195 @@
             /* fire */
             TM_SET_STATE(pTimer, TMTIMERSTATE_EXPIRED_DELIVER);
+            DBGFTRACE_U64_TAG(pVM, pVM->tm.s.u64VirtualSync, pTimer->pszDesc);
             switch (pTimer->enmType)
             {
@@ -2230 +2236 @@
         Assert(u64VirtualNow2 >= u64VirtualNow);
 #ifdef DEBUG_bird
-        AssertMsg(pVM->tm.s.u64VirtualSync >= u64Now, ("%'RU64 < %'RU64\n", pVM->tm.s.u64VirtualSync, u64Now));
+        //AssertMsg(pVM->tm.s.u64VirtualSync >= u64Now, ("%'RU64 < %'RU64\n", pVM->tm.s.u64VirtualSync, u64Now));
 #endif
+        if (pVM->tm.s.u64VirtualSync < u64Now)
+            DBGFTRACE_U64_TAG(pVM, u64Now - pVM->tm.s.u64VirtualSync, "u64VirtualSync < u64Now");
+
         const uint64_t offSlack = pVM->tm.s.u64VirtualSync - u64Now;
         STAM_STATS({
@@ -2275 +2284 @@
                 ASMAtomicWriteBool(&pVM->tm.s.fVirtualSyncCatchUp, false);
                 Log4(("TM: %'RU64/-%'8RU64: caught up [pt]\n", u64VirtualNow2 - offNew, offLag));
+                DBGFTRACE_U64_TAG(pVM, u64VirtualNow2 - offNew, "vs caught up [pt]");
             }
             else if (offLag <= pVM->tm.s.u64VirtualSyncCatchUpGiveUpThreshold)
@@ -2288 +2298 @@
                     ASMAtomicWriteU32(&pVM->tm.s.u32VirtualSyncCatchUpPercentage, pVM->tm.s.aVirtualSyncCatchUpPeriods[i].u32Percentage);
                     Log4(("TM: %'RU64/%'8RU64: adj %u%%\n", u64VirtualNow2 - offNew, offLag, pVM->tm.s.u32VirtualSyncCatchUpPercentage));
+                    DBGFTRACE_U64_TAG(pVM, pVM->tm.s.u32VirtualSyncCatchUpPercentage, "vs adj");
                 }
+                else
+                    DBGFTRACE_U64_TAG(pVM, u64VirtualNow2 - offNew, "vs resuming catch up");
                 pVM->tm.s.u64VirtualSyncCatchUpPrev = u64VirtualNow2;
             }
@@ -2300 +2313 @@
                 Log4(("TM: %'RU64/%'8RU64: give up %u%%\n", u64VirtualNow2 - offNew, offLag, pVM->tm.s.u32VirtualSyncCatchUpPercentage));
                 LogRel(("TM: Giving up catch-up attempt at a %'RU64 ns lag; new total: %'RU64 ns\n", offLag, offNew));
+                DBGFTRACE_U64_TAG(pVM, u64VirtualNow2 - offNew, "vs gave up");
             }
         }
@@ -2316 +2330 @@
                 ASMAtomicWriteBool(&pVM->tm.s.fVirtualSyncCatchUp, true);
                 Log4(("TM: %'RU64/%'8RU64: catch-up %u%%\n", u64VirtualNow2 - offNew, offLag, pVM->tm.s.u32VirtualSyncCatchUpPercentage));
+                DBGFTRACE_U64_TAG(pVM, pVM->tm.s.u32VirtualSyncCatchUpPercentage, "vs start");
             }
             else
@@ -2324 +2339 @@
                 Log4(("TM: %'RU64/%'8RU64: give up\n", u64VirtualNow2 - offNew, offLag));
                 LogRel(("TM: Not bothering to attempt catching up a %'RU64 ns lag; new total: %'RU64\n", offLag, offNew));
+                DBGFTRACE_U64_TAG(pVM, u64VirtualNow2 - offNew, "vs don't bother");
             }
         }
+        else
+            DBGFTRACE_U64_TAG(pVM, u64VirtualNow2 - offNew, "vs resuming");
 
         /*

trunk/src/VBox/VMM/VMMRC/VMMRC.def

@@ -46 +46 @@
     TMTimerGetFreq
     TMTimerIsActive
+    TMTimerIsLockOwner
+    TMTimerLock
     TMTimerSet
     TMTimerSetRelative
@@ -53 +55 @@
     TMTimerSetFrequencyHint
     TMTimerStop
+    TMTimerUnlock
     TRPMGCHandlerGeneric
     TRPMGCHandlerInterupt