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Date: Wed, 19 Mar 2008 23:54:12 -1000 (HST)
From: Jeff Roberson <jroberson@chesapeake.net>
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To: Robert Watson <rwatson@FreeBSD.org>
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Cc: Daniel Eischen <deischen@FreeBSD.org>, arch@FreeBSD.org,
	Alfred Perlstein <alfred@FreeBSD.org>,
	David Xu <davidxu@FreeBSD.org>, freebsd-arch@FreeBSD.org
Subject: Re: Getting rid of the static msleep priority boost
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On Thu, 20 Mar 2008, Robert Watson wrote:

>
> On Wed, 19 Mar 2008, Jeff Roberson wrote:
>
>>> Perhaps there are no performance differences, but the cv/mutex primitives 
>>> are a nice clean interface that most everyone understands.  If you are 
>>> going to write a professional OS from the ground up, I doubt you are going 
>>> to have anything as convoluted as msleep() as part of your kernel API/ABI.
>> 
>> One real obstacle to converting all locations to cv_* is the lack of 
>> support for anything other than mtx def mutexes in the cv api.  It also 
>> just doesn't seem like a good use of developer resources regardless of how 
>> you feel about msleep.
>
> I thought condvar was converted in 7.x to accepting a struct lock for 
> precisely this reason?  I assume (perhaps incorrectly) that it can't be used 
> with spin mutexes, but thought, as a result, that we could now use it with
> other lock types, such as sx locks?

You are right.  John did it at the same time.  Good on em.

>
> Robert N M Watson
> Computer Laboratory
> University of Cambridge
>