Changeset 27932 in vbox

Timestamp:

Apr 1, 2010 12:39:15 PM (15 years ago)

Author:

vboxsync

Message:

DrvChar.cpp: Wait for all threads that have been created with the RTTHREADFLAGS_WAITABLE flag or well leak stuff. Don't try signal the semaphore if PDMDrvHlpAttach failed.

File:

• trunk/src/VBox/Devices/Serial/DrvChar.cpp (modified) (10 diffs)

trunk/src/VBox/Devices/Serial/DrvChar.cpp

@@ -1 +1 @@
 /* $Id$ */
 /** @file
- * VBox stream I/O devices: Generic char driver
+ * Driver that PDMISTREAM into PDMICHARCONNECTOR / PDMICHARPORT.
+ *
+ * Converts synchronous calls (PDMICHARCONNECTOR::pfnWrite, PDMISTREAM::pfnRead)
+ * into asynchronous ones.
  */
 
 /*
- * Copyright (C) 2006-2007 Sun Microsystems, Inc.
+ * Copyright (C) 2006-2010 Sun Microsystems, Inc.
  *
  * This file is part of VirtualBox Open Source Edition (OSE), as
@@ -76 +79 @@
     /** Internal send FIFO queue */
     uint8_t                     aSendQueue[CHAR_MAX_SEND_QUEUE];
-    uint32_t                    iSendQueueHead;
+    uint32_t volatile           iSendQueueHead;
     uint32_t                    iSendQueueTail;
 
@@ -142 +145 @@
 
 /**
- * Send thread loop.
+ * Send thread loop - pushes data down thru the driver chain.
  *
  * @returns 0 on success.
@@ -152 +155 @@
     PDRVCHAR pThis = (PDRVCHAR)pvUser;
 
-    for(;;)
+    while (!pThis->fShutdown)
     {
         int rc = RTSemEventWait(pThis->SendSem, RT_INDEFINITE_WAIT);
@@ -161 +164 @@
          * Write the character to the attached stream (if present).
          */
-        if (    !pThis->fShutdown
-            &&  pThis->pDrvStream)
+        if (    pThis->fShutdown
+            ||  !pThis->pDrvStream)
+            break;
+
+        while (   pThis->iSendQueueTail != pThis->iSendQueueHead
+               && !pThis->fShutdown)
         {
-            while (pThis->iSendQueueTail != pThis->iSendQueueHead)
-            {
-                size_t cbProcessed = 1;
-
-                rc = pThis->pDrvStream->pfnWrite(pThis->pDrvStream, &pThis->aSendQueue[pThis->iSendQueueTail], &cbProcessed);
-                if (RT_SUCCESS(rc))
-                {
-                    Assert(cbProcessed);
-                    pThis->iSendQueueTail++;
-                    pThis->iSendQueueTail &= CHAR_MAX_SEND_QUEUE_MASK;
-                }
-                else if (rc == VERR_TIMEOUT)
-                {
-                    /* Normal case, just means that the stream didn't accept a new
-                     * character before the timeout elapsed. Just retry. */
-                    rc = VINF_SUCCESS;
-                }
-                else
-                {
-                    LogFlow(("Write failed with %Rrc; skipping\n", rc));
-                    break;
-                }
+            size_t cbProcessed = 1;
+
+            rc = pThis->pDrvStream->pfnWrite(pThis->pDrvStream, &pThis->aSendQueue[pThis->iSendQueueTail], &cbProcessed);
+            if (RT_SUCCESS(rc))
+            {
+                Assert(cbProcessed);
+                pThis->iSendQueueTail++;
+                pThis->iSendQueueTail &= CHAR_MAX_SEND_QUEUE_MASK;
+            }
+            else if (rc == VERR_TIMEOUT)
+            {
+                /* Normal case, just means that the stream didn't accept a new
+                 * character before the timeout elapsed. Just retry. */
+                rc = VINF_SUCCESS;
+            }
+            else
+            {
+                LogFlow(("Write failed with %Rrc; skipping\n", rc));
+                break;
             }
         }
-        else
-            break;
-    }
-
-    pThis->SendThread = NIL_RTTHREAD;
+    }
 
     return VINF_SUCCESS;
@@ -263 +263 @@
     }
 
-    pThis->ReceiveThread = NIL_RTTHREAD;
-
     return VINF_SUCCESS;
 }
@@ -312 +310 @@
     PDMDRV_CHECK_VERSIONS_RETURN_VOID(pDrvIns);
 
+    /*
+     * Tell the threads to shut down.
+     */
     pThis->fShutdown = true;
-    if (pThis->ReceiveThread)
-    {
-        RTThreadWait(pThis->ReceiveThread, 1000, NULL);
-        if (pThis->ReceiveThread != NIL_RTTHREAD)
-            LogRel(("Char%d: receive thread did not terminate\n", pDrvIns->iInstance));
-    }
-
-    /* Empty the send queue */
-    pThis->iSendQueueTail = pThis->iSendQueueHead = 0;
-
-    RTSemEventSignal(pThis->SendSem);
-    RTSemEventDestroy(pThis->SendSem);
-    pThis->SendSem = NIL_RTSEMEVENT;
-
-    if (pThis->SendThread)
-    {
-        RTThreadWait(pThis->SendThread, 1000, NULL);
-        if (pThis->SendThread != NIL_RTTHREAD)
-            LogRel(("Char%d: send thread did not terminate\n", pDrvIns->iInstance));
+    if (pThis->SendSem != NIL_RTSEMEVENT)
+    {
+        RTSemEventSignal(pThis->SendSem);
+        RTSemEventDestroy(pThis->SendSem);
+        pThis->SendSem = NIL_RTSEMEVENT;
+    }
+
+    /*
+     * Wait for the threads.
+     * ASSUMES that PDM destroys the driver chain from the the bottom and up.
+     */
+    if (pThis->ReceiveThread != NIL_RTTHREAD)
+    {
+        int rc = RTThreadWait(pThis->ReceiveThread, 300000, NULL);
+        if (RT_SUCCESS(rc))
+            pThis->ReceiveThread = NIL_RTTHREAD;
+        else
+            LogRel(("Char%d: receive thread did not terminate (%Rrc)\n", pDrvIns->iInstance, rc));
+    }
+
+    if (pThis->SendThread != NIL_RTTHREAD)
+    {
+        int rc = RTThreadWait(pThis->SendThread, 30000, NULL);
+        if (RT_SUCCESS(rc))
+            pThis->SendThread = NIL_RTTHREAD;
+        else
+            LogRel(("Char%d: send thread did not terminate (%Rrc)\n", pDrvIns->iInstance, rc));
     }
 }
@@ -350 +359 @@
      * Init basic data members and interfaces.
      */
+    pThis->fShutdown                        = false;
     pThis->ReceiveThread                    = NIL_RTTHREAD;
-    pThis->fShutdown                        = false;
+    pThis->SendThread                       = NIL_RTTHREAD;
+    pThis->SendSem                          = NIL_RTSEMEVENT;
     /* IBase. */
     pDrvIns->IBase.pfnQueryInterface        = drvCharQueryInterface;
@@ -383 +394 @@
     if (pThis->pDrvStream->pfnRead)
     {
-        rc = RTThreadCreate(&pThis->ReceiveThread, drvCharReceiveLoop, (void *)pThis, 0, RTTHREADTYPE_IO, RTTHREADFLAGS_WAITABLE, "CharRecv");
+        rc = RTThreadCreate(&pThis->ReceiveThread, drvCharReceiveLoop, (void *)pThis, 0,
+                            RTTHREADTYPE_IO, RTTHREADFLAGS_WAITABLE, "CharRecv");
         if (RT_FAILURE(rc))
             return PDMDrvHlpVMSetError(pDrvIns, rc, RT_SRC_POS, N_("Char#%d cannot create receive thread"), pDrvIns->iInstance);
@@ -389 +401 @@
 
     rc = RTSemEventCreate(&pThis->SendSem);
-    AssertRC(rc);
-
-    rc = RTThreadCreate(&pThis->SendThread, drvCharSendLoop, (void *)pThis, 0, RTTHREADTYPE_IO, RTTHREADFLAGS_WAITABLE, "CharSend");
+    AssertRCReturn(rc, rc);
+
+    rc = RTThreadCreate(&pThis->SendThread, drvCharSendLoop, (void *)pThis, 0,
+                        RTTHREADTYPE_IO, RTTHREADFLAGS_WAITABLE, "CharSend");
     if (RT_FAILURE(rc))
         return PDMDrvHlpVMSetError(pDrvIns, rc, RT_SRC_POS, N_("Char#%d cannot create send thread"), pDrvIns->iInstance);