diff options
Diffstat (limited to 'src/VBox/Main/hgcm/HGCMThread.cpp')
| -rw-r--r-- | src/VBox/Main/hgcm/HGCMThread.cpp | 37 |
1 files changed, 30 insertions, 7 deletions
diff --git a/src/VBox/Main/hgcm/HGCMThread.cpp b/src/VBox/Main/hgcm/HGCMThread.cpp index f60ae03a0..edeadcffb 100644 --- a/src/VBox/Main/hgcm/HGCMThread.cpp +++ b/src/VBox/Main/hgcm/HGCMThread.cpp @@ -89,6 +89,7 @@ class HGCMThread: public HGCMObject /* A caller thread waits for completion of a SENT message on this event. */ RTSEMEVENTMULTI m_eventSend; + int32_t volatile m_i32MessagesProcessed; /* Critical section for accessing the thread data, mostly for message queues. */ RTCRITSECT m_critsect; @@ -212,6 +213,7 @@ HGCMThread::HGCMThread () m_thread (NIL_RTTHREAD), m_eventThread (0), m_eventSend (0), + m_i32MessagesProcessed (0), m_fu32ThreadFlags (0), m_pMsgInputQueueHead (NULL), m_pMsgInputQueueTail (NULL), @@ -432,12 +434,30 @@ int HGCMThread::MsgPost (HGCMMsgCore *pMsg, PHGCMMSGCALLBACK pfnCallback, bool f if (fWait) { + /* Immediately check if the message has been processed. */ while ((pMsg->m_fu32Flags & HGCM_MSG_F_PROCESSED) == 0) { - RTSemEventMultiWait (m_eventSend, RT_INDEFINITE_WAIT); - RTSemEventMultiReset (m_eventSend); + /* Poll infrequently to make sure no completed message has been missed. */ + RTSemEventMultiWait (m_eventSend, 1000); LogFlow(("HGCMThread::MsgPost: wait completed flags = %08X\n", pMsg->m_fu32Flags)); + + if ((pMsg->m_fu32Flags & HGCM_MSG_F_PROCESSED) == 0) + { + RTThreadYield(); + } + } + + /* 'Our' message has been processed, so should reset the semaphore. + * There is still possible that another message has been processed + * and the semaphore has been signalled again. + * Reset only if there are no other messages completed. + */ + int32_t c = ASMAtomicDecS32(&m_i32MessagesProcessed); + Assert(c >= 0); + if (c == 0) + { + RTSemEventMultiReset (m_eventSend); } rc = pMsg->m_rcSend; @@ -580,6 +600,14 @@ void HGCMThread::MsgComplete (HGCMMsgCore *pMsg, int32_t result) bool fWaited = ((pMsg->m_fu32Flags & HGCM_MSG_F_WAIT) != 0); + if (fWaited) + { + ASMAtomicIncS32(&m_i32MessagesProcessed); + + /* This should be done before setting the HGCM_MSG_F_PROCESSED flag. */ + pMsg->m_rcSend = result; + } + /* The message is now completed. */ pMsg->m_fu32Flags &= ~HGCM_MSG_F_IN_PROCESS; pMsg->m_fu32Flags &= ~HGCM_MSG_F_WAIT; @@ -591,11 +619,6 @@ void HGCMThread::MsgComplete (HGCMMsgCore *pMsg, int32_t result) if (fWaited) { - /* If message is being waited, then it is referenced by the waiter and the pointer - * if valid even after hgcmObjDeleteHandle. - */ - pMsg->m_rcSend = result; - /* Wake up all waiters. so they can decide if their message has been processed. */ RTSemEventMultiSignal (m_eventSend); } |