[问答]

工作线程用于EP6调用xferdata得到锁定

1957 dev

问答对人有帮助，内容完整，我也想知道答案 0 我找不到文档中提到的任何地方。当我从主线程中剥离到批量IO调用时，一切都正常。当我有一个工人线程为EP6调用XFEDATA和一个EP8调用XFEDATA的线程时，每个线程将数据塞进一个C锁队列，并且被锁保护，我得到一些非常可怕的锁存器，挂起DEV环境直到我拔下USB。带锁保护的排队的东西应该很好。很多都是在网上做的。幸运的是，它很容易在几秒钟内繁殖。但是，不允许每个调用批量XFEDATA的两个线程吗？以上来自于百度翻译以下为原文 I cannot find anyplace in the documentation that this is mentioned. When I strip down to bulk IO calls from the main thread, all is OK. When I have a worker threadfor EP6 calling xferdata and a thread for EP8 calling xferdata , and each thread stuff the data into a c# Queue<> protected by Lock I am getting some really horrid lockups that hang the dev environment until I unplug the USB. The Queue stuff with lock protecting it shoudl be fine. Lots do that all over the net. Luckily it reproduces easily in seconds. But perhaps two threads each calling bulk xferdata isn't allowed? 0
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答案对人有帮助，有参考价值 0 我用xferdata，以及异步begindataxfer / waitforxfer / finishdataxfer，多个线程之间没有任何问题，但我没有把结果在一个共享的队列。您使用的是哪种锁定机构？锁（这）{ /* / }做的东西是一种很好的方式得到死锁因为其他代码可以锁在这不同的原因。你应该创建专门用于锁定数据传输对象和锁定，只传输代码。对象datatransferlockobject =新object()；锁（datatransferlockobject）{ / / }做的东西，其实你真的应该使用队列。同步的方法得到一个队列的包装，不需要通过一个锁保护；看到HTTP：/ / MSDN。微软。COM / en-u. .. ueue.synchronized.aspx缩小你的问题，你可以试试其他的东西。让xferdata会但注释添加到队列。将它们添加到两个单独的队列中。就是说，我有我的app CyAPI函数不仅造成问题，但Visual Studio锁定直到我拔掉插头。我认为问题是通过托管字节[]数组的非托管程序。在转移过程中，CLR决定将缓存在内存中，可能是为了保持堆太分散。然而，由于柏驱动程序是非托管的，有没有办法知道，CLR是移动的东西，在它的后面，所以继续读/写旧的记忆。这会导致各种问题；应用程序可以锁定，或抛出NullReferenceException或者更奇特的executionengineexception，但是对我来说，例外总是扔在主线程和辅助线程（也许不是司机是在主线程上下文执行线程而不是调用线程？）考虑到当你的项目添加到队列中，它可能会导致新的内存被分配和老内存被释放。最终，记忆变得支离破碎，CLR将周围的缓冲区，如果CLR动作缓冲而司机积极转移到/从它，你会崩溃。该解决方案是使用一个固定的块缓冲区的范围的时间，或者使用GCHandle类销缓冲记忆如此之CLR不会移动它们。注意我所说的“缓冲区”，复数；这些规则不仅适用于数据缓冲区，但重叠单传输缓冲区以及！我结束了PinnedBuffer的课，把一个字节[]，引脚在构造函数的缓冲区写入。不幸的是，字节[ ]必须是一个公共领域，因为柏API使用ref参数和参考参数有效的参数列表是比你想象的短很… 以上来自于百度翻译以下为原文 I used XferData, as well as the asynchronous BeginDataXfer/WaitForXfer/FinishDataXfer, across multiple threads without any problems, but I was not placing the results in a shared queue. What kind of locking mechanism are you using? lock (this) { / do stuff /} is a good way to get deadlocks because other code can lock on this for different reasons. You should create an object specifically for locking data transfers and lock only the transfers on only that code. Object DataTransferLockObject = new Object(); lock (DataTransferLockObject) { / do stuff */ } Actually you should really use the Queue.Synchronized method to get a queue wrapper that doesn't need protected by a lock; see http://msdn.microsoft.com/en-u...ueue.synchronized.aspx To narrow down your problem, you could try some other things. Keep both XferData's going but comment out adding them to the queue. Add them to two separate queues. That said, I have had problems with the CyAPI causing not only my app, but Visual Studio to lock up until I pulled the plug. I believe the problem deals with passing Managed byte[] arrays to the Unmanaged driver. During the transfer, the CLR decides to move the buffer around in memory, probably in an effort to keep the heap from becoming too fragmented. However, since the Cypress driver is unmanaged, it has no way of knowing that the CLR is moving things behind its back, and so it continues to read/write to old memory. This can cause all kinds of problems; the app might lock, or throw a NullReferenceException or the even more exotic ExecutionEngineException, but for me the exceptions were always thrown on the main thread and not the worker thread (perhaps the driver thread was executing in the context of the main thread instead of the calling thread?) Consider that when you add an item to the queue, it may cause new memory to be allocated and old memory to be freed. Eventually, memory becomes so fragmented that the CLR moves the buffers around, and if the CLR moves your buffer while the driver is actively transferring to/from it, you will get crashes. The solution is to use a fixed block for duration of the buffers' scopes, or to use the GCHandle class to pin the buffers in memory so the CLR won't move them around. Note that I said "buffers", plural; these rules apply not only to the data buffer, but to the overlapped and single-transfer buffers as well! I ended up writing a PinnedBuffer class that wraps a byte[] which pins the buffer in the constructor. Unfortunately, the byte[] must be a public field, because the Cypress API uses ref parameters and the list of valid arguments for ref parameters is actually much shorter than you think...

2019-3-4 16:24:22 评论举报刘佳