[PATCH] Check for preemption after lowering a thread's priority

Ryan Stone rysto32 at gmail.com
Thu Feb 9 18:02:44 UTC 2017

I've just put up a phabricator review for a fix to ULE and 4BSD for a
priority inversion problem.  The issue is that after a running thread's
priority is lowered (usually due to releasing a mutex and having a priority
load revoked), the scheduler does not check whether the thread should now
be preempted by a thread waiting in the runq.  See this old ML post for a
detailed description of one instance that I saw:


The review can be found here:

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