[ 
https://issues.apache.org/jira/browse/THRIFT-3932?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15540555#comment-15540555
 ] 

ASF GitHub Bot commented on THRIFT-3932:
----------------------------------------

Github user nsuke commented on the issue:

    https://github.com/apache/thrift/pull/1103
  
    It looks succeeding to me :tada:


> C++ ThreadManager has a rare termination race
> ---------------------------------------------
>
>                 Key: THRIFT-3932
>                 URL: https://issues.apache.org/jira/browse/THRIFT-3932
>             Project: Thrift
>          Issue Type: Bug
>          Components: C++ - Library
>            Reporter: Buğra Gedik
>            Assignee: James E. King, III
>         Attachments: thrift-patch
>
>          Time Spent: 8h
>  Remaining Estimate: 0h
>
> {{ThreadManger::join}} calls {{stopImpl(true)}}, which in turn calls 
> {{removeWorker(workerCount_);}}. The latter waits until {{while (workerCount_ 
> != workerMaxCount_)}}. Within the {{run}} method of the workers, the last 
> thread that detects {{workerCount_ == workerMaxCount_}} notifies 
> {{removeWorker}}. The {{run}} method has the following additional code that 
> is executed at the very end:
> {code}
>     {
>       Synchronized s(manager_->workerMonitor_);
>       manager_->deadWorkers_.insert(this->thread());
>       if (notifyManager) {
>         manager_->workerMonitor_.notify();
>       }
>     }
> {code}
> This is an independent synchronized block. Now assume 2 threads. One of them 
> has {{notifyManager=true}} as it detected the {{workerCount_ == 
> workerMaxCount_}} condition earlier. It is possible that this thread gets to 
> execute  the above code block first, {{ThreadManager}}'s {{removeWorker}} 
> method unblocks, and eventually {{ThreadManager}}'s {{join}} returns and the 
> object is destructed. When the other thread reaches the synchronized block 
> above, it will crash, as the manager is not around anymore.
> Besides, {{ThreadManager}} never joins its threads.
> Attached is a patch.



--
This message was sent by Atlassian JIRA
(v6.3.4#6332)

Reply via email to