Properly shut down fastcgi worker threads when connection is closed
Summary: If the fastcgi connection from the webserver was closed while a
request was reading its POST data, the worker thread processing that request
would get stuck indefinitely waiting for the rest of the data to arrive. Given
enough time, all worker threads in the server could get stuck, causing the
server to become completely unresponsive until a restart. Make sure we notify
the appropriate condition variable to avoid this.
Reviewed By: @ptarjan
Differential Revision:
D1476306