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Date: Sat, 11 Aug 2007 14:46:12 +0200
From: Roman Divacky <rdivacky@freebsd.org>
To: hackers@freebsd.org
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Subject: strange KASSERT in _sleep()
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hi

tsleep() maps to _sleep() with lock = NULL,

the _sleep() contains this:

  KASSERT(timo != 0 || mtx_owned(&Giant) || lock != NULL ||
              ident == &lbolt, ("sleeping without a lock"));


which simplifies for tsleep(foo, ...) where foo != lbolt to
"timo != 0 || mtx_owned(&Giant)"

why do I have to hold Giant or have timo != 0 when calling tsleep?

thnx for explanation

roman