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From: Ken Brown <kbrown@cornell.edu>
To: cygwin <cygwin@cygwin.com>
Subject: timerfd deadlock
Date: Fri, 7 Jun 2019 12:10:17 +0000
Message-ID: <17657e77-6d7c-7367-3e6f-54e2586ed40c@cornell.edu>
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While testing some new pipe code, I'm occasionally seeing a timerfd deadlock: 
The main thread is stuck in timerfd_tracker::dtor at timerfd.cc:354, waiting for 
the timerfd thread to close; and the timerfd thread is stuck at timerfd.cc:140, 
waiting to acquire a mutex that's held by timerfd_tracker::dtor.

I see this maybe 1 out of 4 times that I run 'make -j13' on a clean emacs source 
tree, and I see it only when my new pipe code is installed.  So I don't know if 
this is a bug in my code or if it's just coincidence that my code happens to 
trigger a timerfd bug.

Ken

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