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Date: Tue, 18 Mar 2008 23:53:14 -1000 (HST)
From: Jeff Roberson <jroberson@chesapeake.net>
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To: David Xu <davidxu@FreeBSD.org>
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Cc: Daniel Eischen <deischen@FreeBSD.org>, arch@FreeBSD.org
Subject: Re: Getting rid of the static msleep priority boost
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On Wed, 19 Mar 2008, David Xu wrote:

> Daniel Eischen wrote:
>
>> I'm not sure if any of the above remove the priority from the API,
>> but it would be nice to get rid of msleep totally and replace it
>> with an equivalent cv_wait().
>> 
>
> And create sleep queue in each cv to get rid of shared sleep queue
> lock ?

Some spinlock is required to interlock with the scheduler lock via 
thread_lock().  So I don't think you can get rid of that layer.  You also 
wouldn't want to have the cost of a 'struct sleepqueue' everywhere you 
want a msleep/condvar.

I personally don't see any real advantage to using condvar everywhere. 
The only thing you really get is protection against spurious wakeups.

Thanks,
Jeff

>
> Regards,
> David Xu
>