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Date: Fri, 12 Dec 2014 04:34:10 -0300
Message-ID: <CAN19L9E5sfypELzXG5Qh7aRyir2A0W8qfJyQy_OBVujs6gW+uA@mail.gmail.com>
Subject: Re: Locking a MTX_DEF inside an interrupt thread
From: Martin Galvan <omgalvan.86@gmail.com>
To: freebsd-drivers@freebsd.org, nparhar@gmail.com
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2014-12-11 16:58 GMT-03:00 Navdeep Parhar <nparhar@gmail.com>:
> MTX_DEF mutexes can block but never sleep, and it is perfectly safe to acquire
> them in an ithread.

Thanks a lot for your answer. At first I was a bit confused on what
the actual difference between "blocking" and "sleeping" was, but then
I read the "Bounded vs Unbounded Sleep" section from locking(9) and it
cleared things out a bit.

I still don't understand why can't we sleep (i.e. do an 'unbounded
sleep') inside an ithread. What would be the problem, exactly?