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Date: Mon, 05 May 2003 17:25:07 -0400 (EDT)
From: John Baldwin <jhb@FreeBSD.org>
To: Petri Helenius <pete@he.iki.fi>
cc: freebsd-current@FreeBSD.org
cc: sos@FreeBSD.org
Subject: Re: kthread_exit and giant
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On 05-May-2003 Petri Helenius wrote:
>> 
>> The kthread is supposed to acquire Giant before calling kthread_exit().
>> Actually, my guess is that the ar kthread needs to acquire Giant for the
>> lifetime of the thread.  I have an untested patch locally:
>> 
> I thought the lifetime of the thread is the duration of the rebuild process? Which
> can be minutes to hours. Locking giant for that kind of time does not sound
> right, so locking it just before thread exit sounds like the right thing to do, 
> as long as the code othervise keeps critical sections locked.

Giant is dropped when a thread sleeps.  It is designed to protect code
that is not fully locked yet.

-- 

John Baldwin <jhb@FreeBSD.org>  <><  http://www.FreeBSD.org/~jhb/
"Power Users Use the Power to Serve!"  -  http://www.FreeBSD.org/