Changeset 79485 in vbox

Timestamp:

Jul 3, 2019 5:10:33 AM (6 years ago)

Author:

vboxsync

Message:

VMM/HMVMXR0: Safer to flag host-context change while interrupts are still disabled, though I think in theory it should work even if RTMpCpuId is called when preemptible as the hook should cover it. Comments. Renamed StatSwitchExportHostState to StatExportHostState.

Location:

trunk/src/VBox/VMM

Files:

• VMMR0/HMVMXR0.cpp (modified) (6 diffs)
• VMMR3/HM.cpp (modified) (2 diffs)
• include/HMInternal.h (modified) (2 diffs)

trunk/src/VBox/VMM/VMMR0/HMVMXR0.cpp

@@ -1374 +1374 @@
     }
 
+    /*
+     * Disable interrupts to prevent being preempted while we switch the current VMCS as the
+     * preemption hook code path acquires the current VMCS.
+     */
     RTCCUINTREG const fEFlags = ASMIntDisableFlags();
+
     int rc = hmR0VmxSwitchVmcs(pVmcsInfoFrom, pVmcsInfoTo);
     if (RT_SUCCESS(rc))
     {
         pVCpu->hm.s.vmx.fSwitchedToNstGstVmcs = fSwitchToNstGstVmcs;
-        ASMSetFlags(fEFlags);
 
         /*
@@ -1390 +1394 @@
         else
             ASMAtomicUoOrU64(&pVCpu->hm.s.fCtxChanged, HM_CHANGED_HOST_CONTEXT | HM_CHANGED_VMX_HOST_GUEST_SHARED_STATE);
+
+        ASMSetFlags(fEFlags);
 
         /*
@@ -9147 +9153 @@
     Assert(!VMMRZCallRing3IsEnabled(pVCpu));
 
-    RTCPUID idCpu = RTMpCpuId();
+    RTCPUID const idCpu = RTMpCpuId();
     Log4Func(("HostCpuId=%u\n", idCpu));
 
@@ -11660 +11666 @@
     if (pVCpu->hm.s.fCtxChanged & HM_CHANGED_HOST_CONTEXT)
     {
-        int rc = hmR0VmxExportHostState(pVCpu);
-        AssertRC(rc);
-        STAM_COUNTER_INC(&pVCpu->hm.s.StatSwitchExportHostState);
+        hmR0VmxExportHostState(pVCpu);
+        STAM_COUNTER_INC(&pVCpu->hm.s.StatExportHostState);
     }
     Assert(!(pVCpu->hm.s.fCtxChanged & HM_CHANGED_HOST_CONTEXT));
@@ -12066 +12071 @@
 
     /*
-     * Switch to the nested-guest VMCS as we may have transitioned to executing the
-     * nested-guest without leaving ring-0. Otherwise, if we came from ring-3 we would have
+     * Switch to the nested-guest VMCS as we may have transitioned from executing the
+     * guest without leaving ring-0. Otherwise, if we came from ring-3 we would have
      * loaded the nested-guest VMCS while entering the VMX ring-0 session.
      */
@@ -12077 +12082 @@
         else
         {
-            LogRelFunc(("Failed to switch to the guest VMCS. rc=%Rrc\n", rc));
+            LogRelFunc(("Failed to switch to the nested-guest VMCS. rc=%Rrc\n", rc));
             return rc;
         }

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

@@ -802 +802 @@
         HM_REG_COUNTER(&pVCpu->hm.s.StatSwitchPreempt,          "/HM/CPU%d/Switch/Preempting", "EMT has been preempted while in HM context.");
 #ifdef VBOX_WITH_STATISTICS
-        HM_REG_COUNTER(&pVCpu->hm.s.StatSwitchExportHostState,  "/HM/CPU%d/Switch/ExportHostState", "Preemption or entering with nested-guest VMCS caused re-exporting of host state.");
         HM_REG_COUNTER(&pVCpu->hm.s.StatSwitchNstGstVmexit,     "/HM/CPU%d/Switch/NstGstVmexit", "Nested-guest VM-exit occurred.");
 
@@ -836 +835 @@
         HM_REG_COUNTER(&pVCpu->hm.s.StatExportFull,             "/HM/CPU%d/Export/Full", "VM-entry exporting the full guest-state.");
         HM_REG_COUNTER(&pVCpu->hm.s.StatLoadGuestFpu,           "/HM/CPU%d/Export/GuestFpu", "VM-entry loading the guest-FPU state.");
+        HM_REG_COUNTER(&pVCpu->hm.s.StatExportHostState,        "/HM/CPU%d/Export/HostState", "VM-entry exporting host-state.");
 
         HM_REG_COUNTER(&pVCpu->hm.s.StatVmxCheckBadRmSelBase,   "/HM/CPU%d/VMXCheck/RMSelBase", "Could not use VMX due to unsuitable real-mode selector base.");

trunk/src/VBox/VMM/include/HMInternal.h

@@ -1202 +1202 @@
     STAMCOUNTER             StatSwitchApicAccessToR3;
     STAMCOUNTER             StatSwitchPreempt;
-    STAMCOUNTER             StatSwitchExportHostState;
     STAMCOUNTER             StatSwitchNstGstVmexit;
 
@@ -1216 +1215 @@
     STAMCOUNTER             StatExportFull;
     STAMCOUNTER             StatLoadGuestFpu;
+    STAMCOUNTER             StatExportHostState;
 
     STAMCOUNTER             StatVmxCheckBadRmSelBase;