Chunwei Chen e843553d03 Don't hold mutex until release cv in cv_wait ... If a thread is holding mutex when doing cv_destroy, it might end up waiting a thread in cv_wait. The waiter would wake up trying to aquire the same mutex and cause deadlock. We solve this by move the mutex_enter to the bottom of cv_wait, so that the waiter will release the cv first, allowing cv_destroy to succeed and have a chance to free the mutex. This would create race condition on the cv_mutex. We use xchg to set and check it to ensure we won't be harmed by the race. This would result in the cv_mutex debugging becomes best-effort. Also, the change reveals a race, which was unlikely before, where we call mutex_destroy while test threads are still holding the mutex. We use kthread_stop to make sure the threads are exit before mutex_destroy. Signed-off-by: Chunwei Chen <tuxoko@gmail.com> Signed-off-by: Brian Behlendorf <behlendorf1@llnl.gov> Signed-off-by: Tim Chase <tim@chase2k.com> Issue zfsonlinux/zfs#4166 Issue zfsonlinux/zfs#4106		2016-01-12 15:18:44 -08:00
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spl	Don't hold mutex until release cv in cv_wait	2016-01-12 15:18:44 -08:00
splat	Don't hold mutex until release cv in cv_wait	2016-01-12 15:18:44 -08:00
.gitignore	gitignore: anchor entries at their respective directory	2013-04-02 11:07:52 -07:00
Makefile.in	Prevent rm modules.* when make install	2015-12-02 14:38:20 -08:00