Changeset 37230 in vbox for trunk/src/VBox/HostDrivers

Timestamp:

May 27, 2011 11:20:19 AM (14 years ago)

Author:

vboxsync

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

71952

Message:

SUPDrv.c: A couple of small cleanups.

File:

• trunk/src/VBox/HostDrivers/Support/SUPDrv.c (modified) (8 diffs)

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

@@ -4993 +4993 @@
 
 /**
- * Helper for finding the CPU index from the CPU Id.
- *
- * @param    pGip               The GIP.
- * @param    idCpu              The CPU ID.
+ * Finds our (@a idCpu) entry, or allocates a new one if not found.
  *
  * @returns Index of the CPU in the cache set.
- */
-DECLINLINE(uint32_t) supdrvGipCpuIndexFromCpuId(PSUPGLOBALINFOPAGE pGip, RTCPUID idCpu)
-{
-    uint32_t i = 0;
-
-    /*
-     * Find our entry, or allocate one if not found.
+ * @param   pGip                The GIP.
+ * @param   idCpu               The CPU ID.
+ */
+static uint32_t supdrvGipCpuIndexFromCpuId(PSUPGLOBALINFOPAGE pGip, RTCPUID idCpu)
+{
+    uint32_t i, cTries;
+
+    /*
      * ASSUMES that CPU IDs are constant.
      */
     for (i = 0; i < pGip->cCpus; i++)
         if (pGip->aCPUs[i].idCpu == idCpu)
-            break;
-
-    if (i >= pGip->cCpus)
+            return i;
+
+    cTries = 0;
+    do
+    {
         for (i = 0; i < pGip->cCpus; i++)
         {
@@ -5018 +5018 @@
             ASMAtomicCmpXchgSize(&pGip->aCPUs[i].idCpu, idCpu, NIL_RTCPUID, fRc);
             if (fRc)
-                break;
-        }
-
-    AssertRelease(i < pGip->cCpus);
-    return i;
+                return i;
+        }
+    } while (cTries++ < 32);
+    AssertReleaseFailed();
+    return i - 1;
 }
 
@@ -5056 +5056 @@
     }
 
+    /*
+     * Update the entry.
+     */
     i = supdrvGipCpuIndexFromCpuId(pGip, idCpu);
-
-    /*
-     * Update the entry.
-     */
     idApic = ASMGetApicId();
     ASMAtomicUoWriteU16(&pGip->aCPUs[i].idApic,  idApic);
@@ -5072 +5071 @@
     ASMAtomicWriteU16(&pGip->aiCpuFromCpuSetIdx[iCpuSet], i);
 
+    /* commit it */
     ASMAtomicWriteSize(&pGip->aCPUs[i].enmState, SUPGIPCPUSTATE_ONLINE);
 }
@@ -5098 +5098 @@
     Assert(RTCpuSetIsMemberByIndex(&pGip->PossibleCpuSet, iCpuSet));
     RTCpuSetDelByIndex(&pGip->OnlineCpuSet, iCpuSet);
+
+    /* commit it */
     ASMAtomicWriteSize(&pGip->aCPUs[i].enmState, SUPGIPCPUSTATE_OFFLINE);
 }
@@ -5640 +5642 @@
                                   RTCPUID idCpu, uint8_t idApic, uint64_t iTick)
 {
-    /*
-     * Avoid a potential race when a CPU online notification doesn't fire on the onlined CPU
-     * but the tick creeps in before the event notification is run.
-     */
-    unsigned iCpu = 0;
-    if (iTick == 1)
-    {
-        uint32_t i = supdrvGipCpuIndexFromCpuId(pGip, idCpu);
-        if (pGip->aCPUs[i].enmState == SUPGIPCPUSTATE_OFFLINE)
+    uint32_t iCpu;
+
+    /*
+     * Avoid a potential race when a CPU online notification doesn't fire on
+     * the onlined CPU but the tick creeps in before the event notification is
+     * run.
+     */
+    if (RT_UNLIKELY(iTick == 1))
+    {
+        iCpu = supdrvGipCpuIndexFromCpuId(pGip, idCpu);
+        if (pGip->aCPUs[iCpu].enmState == SUPGIPCPUSTATE_OFFLINE)
             supdrvGipMpEventOnline(pGip, idCpu);
     }
 
     iCpu = pGip->aiCpuFromApicId[idApic];
-
     if (RT_LIKELY(iCpu < pGip->cCpus))
     {
@@ -5659 +5662 @@
         if (pGipCpu->idCpu == idCpu)
         {
-
             /*
              * Start update transaction.
@@ -5683 +5685 @@
     }
 }
+