Re: [reSIProcate] [spam] Re: static StatisticsMessage::AtomicPayload appStats; in poll() may not thread safe

["shen jinti" <jinti.shen@xxxxxxxxx>]

hi maodonghu,

   well, i'm sorry , i doesn't careful inspection with your question,
   
   that is a bug with the code, em. may be appStats can 
move into static global area. I think that appStats can initialize first. may be to avert the thread safe issue.
   
   btw, why you use multi-stack in your process ?
   
    sincerely,
    jinti

在06-10-18， maodonghu <hhmmdd@xxxxxxx> 写道：

Hi, shen jinti

 

　　By the way, I use Pentinum D, it has 2 CPU, so the exception may be easy to encounter.

 

======== 2006-10-18 10:37:34  ========

 

hi maodonghu,

    you must compile with  /MD or /MT option in you all project.
   
    jinti

在06-10-18，maodonghu < hhmmdd@xxxxxxx> 写道：

hi,

I found my multi-thread program that using resiprocate will crashed sometimes when startup, the place is

void
StatisticsMessage::AtomicPayload::loadIn(const Payload& payload)
{
   Lock lock(mMutex); // --> here cause crash, because the mMutex may have not finished its constructor yet.
   Payload::operator=(payload);
}

then I research the source code, I found

void
StatisticsManager::poll()
{
   // get snapshot data now..
   tuFifoSize = mStack.mTransactionController.getTuFifoSize();
   transportFifoSizeSum = mStack.mTransactionController.sumTransportFifoSizes();
   transactionFifoSize = mStack.mTransactionController.getTransactionFifoSize();
   activeTimers = mStack.mTransactionController.getTimerQueueSize();
   activeClientTransactions = mStack.mTransactionController.getNumClientTransactions();
   activeServerTransactions = mStack.mTransactionController.getNumServerTransactions();

   static StatisticsMessage::AtomicPayload appStats; // --> here may not thread safe
   appStats.loadIn(*this);

   // let the app do what it wants with it
   mStack.post(StatisticsMessage(appStats));
}


Because I have multi-SipStacks in my program, so I have multi-StackThread, I think the usage of static local variable here may not thread safe, appStats should be a static member of class StatisticsManager.

the MSDN help also tell us:

Note
Assigning to a static local variable is not thread safe and is not recommended as a programming practice.



maodonghu
hhmmdd@xxxxxxx
2006-10-18

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　　　　　　　　　　　　　　maodonghu

　　　　　　　　　　　　　　hhmmdd@xxxxxxx

　　　　　　　　　　　　　　　2006-10-18