Changeset 12941 in vbox

Timestamp:

Oct 2, 2008 2:50:06 PM (17 years ago)

Author:

vboxsync

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

37366

Message:

Solaris/vboxnetflt: Optimized loopback handling for getting acceptible performance in the worst case scenario of switching from no loopback to loopback.

File:

• trunk/src/VBox/HostDrivers/VBoxNetFlt/solaris/VBoxNetFlt-solaris.c (modified) (9 diffs)

trunk/src/VBox/HostDrivers/VBoxNetFlt/solaris/VBoxNetFlt-solaris.c

@@ -2157 +2157 @@
     size_t cbMsg = MBLKL(pMsg);
 
-    AssertRelease(cbMsg > 0);   /** Yeah, die otherwise! */
-    pTag->pNext = NULL;
     pTag->cbPacket = cbMsg;
     pTag->Checksum = RTCrc32(pMsg->b_rptr, cbMsg);
@@ -2201 +2199 @@
 
     PVBOXNETFLTPACKETID pCur = NULL;
-    if (pPromiscStream->cLoopback < VBOXNETFLT_LOOPBACK_SIZE)
+    if (pPromiscStream->cLoopback < VBOXNETFLT_LOOPBACK_SIZE
+        || (   pPromiscStream->pHead
+            && pPromiscStream->pHead->cbPacket == 0))
     {
         do
@@ -2216 +2216 @@
                 vboxNetFltSolarisInitPacketId(pCur, pMsg);
 
+                pCur->pNext = NULL;
                 pPromiscStream->pHead = pCur;
                 pPromiscStream->pTail = pCur;
@@ -2224 +2225 @@
                 break;
             }
-            else if (   pPromiscStream->pTail
-                     && pPromiscStream->pTail->cbPacket == 0)
+            else if (   pPromiscStream->pHead
+                     && pPromiscStream->pHead->cbPacket == 0)
             {
-                pCur = pPromiscStream->pTail;
+                pCur = pPromiscStream->pHead;
                 vboxNetFltSolarisInitPacketId(pCur, pMsg);
-                pPromiscStream->cLoopback++;
-
-                LogFlow((DEVICE_NAME ":vboxNetFltSolarisQueueLoopback re-used tail checksum=%u cLoopback=%d.\n",
+
+                LogFlow((DEVICE_NAME ":vboxNetFltSolarisQueueLoopback re-used head checksum=%u cLoopback=%d.\n",
                         pCur->Checksum, pPromiscStream->cLoopback));
                 break;
             }
-            else if (pPromiscStream->pTail)
+            else
             {
                 pCur = RTMemAlloc(sizeof(VBOXNETFLTPACKETID));
@@ -2246 +2246 @@
                 vboxNetFltSolarisInitPacketId(pCur, pMsg);
 
-                pPromiscStream->pTail->pNext = pCur;
-                pPromiscStream->pTail = pCur;
+                pCur->pNext = pPromiscStream->pHead;
+                pPromiscStream->pHead = pCur;
                 pPromiscStream->cLoopback++;
 
-                LogFlow((DEVICE_NAME ":vboxNetFltSolarisQueueLoopback added tail checksum=%u cLoopback=%d.\n", pCur->Checksum,
+                LogFlow((DEVICE_NAME ":vboxNetFltSolarisQueueLoopback added head checksum=%u cLoopback=%d.\n", pCur->Checksum,
                         pPromiscStream->cLoopback));
                 break;
@@ -2259 +2259 @@
     {
         /*
-         * Maximum loopback queue size reached. Re-use head as tail.
+         * Maximum loopback queue size reached. Re-use tail as head.
          */
         Assert(pPromiscStream->pHead);
         Assert(pPromiscStream->pTail);
 
+        /*
+         * Find tail's previous item.
+         */
+        PVBOXNETFLTPACKETID pPrev = NULL;
         pCur = pPromiscStream->pHead;
-        pPromiscStream->pHead = pPromiscStream->pHead->pNext;
-        pPromiscStream->pTail->pNext = pCur;
-        pPromiscStream->pTail = pCur;
-        pCur->pNext = NULL;
-        pCur->cbPacket = 0;
-        pPromiscStream->cLoopback--;
+
+        /** @todo consider if this is worth switching to a double linked list... */
+        while (pCur != pPromiscStream->pTail)
+        {
+            pPrev = pCur;
+            pCur = pCur->pNext;
+        }
+
+        pPromiscStream->pTail = pPrev;
+        pPromiscStream->pTail->pNext = NULL;
+        pCur->pNext = pPromiscStream->pHead;
+        pPromiscStream->pHead = pCur;
 
         vboxNetFltSolarisInitPacketId(pCur, pMsg);
-        LogFlow((DEVICE_NAME ":vboxNetFltSolarisQueueLoopback recycled head!! checksum=%u cLoopback=%d\n", pCur->Checksum,
+        LogFlow((DEVICE_NAME ":vboxNetFltSolarisQueueLoopback recycled tail!! checksum=%u cLoopback=%d\n", pCur->Checksum,
                 pPromiscStream->cLoopback));
     }
@@ -2348 +2358 @@
         /*
          * Yes, it really is our own packet, mark it as handled
-         * and move it to the tail and return it's found.
+         * and move it as a "free slot" to the head and return success.
          */
         pCur->cbPacket = 0;
@@ -2354 +2364 @@
         {
             pPrev->pNext = pCur->pNext;
-            pPromiscStream->pTail->pNext = pCur;
-            pPromiscStream->pTail = pCur;
-            pCur->pNext = NULL;
-        }
-        pPromiscStream->cLoopback--;
+            pCur->pNext = pPromiscStream->pHead;
+            pPromiscStream->pHead = pCur;
+        }
         fIsOurPacket = true;
 
-        LogFlow((DEVICE_NAME ":vboxNetFltSolarisIsOurMBlk found packet %p Checksum=%u cLoopbackQ=%d\n", pMsg, Checksum,
+        LogFlow((DEVICE_NAME ":vboxNetFltSolarisIsOurMBlk found packet %p Checksum=%u cLoopback=%d\n", pMsg, Checksum,
                     pPromiscStream->cLoopback));
         break;
@@ -2707 +2715 @@
         }
         else
-            LogRel((DEVICE_NAME ":vboxNetFltPortOsSetActive queue not found!\n"));            
+            LogRel((DEVICE_NAME ":vboxNetFltPortOsSetActive queue not found!\n"));
     }
     else