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From: Sam Leffler <sam@errno.com>
Organization: Errno Consulting
To: "M. Warner Losh" <imp@bsdimp.com>, sam@freebsd.org
Date: Thu, 6 Nov 2003 10:32:37 -0800
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cc: perforce@freebsd.org
Subject: Re: PERFORCE change 41566 for review
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On Thursday 06 November 2003 12:26 am, M. Warner Losh wrote:
> In message: <200311060513.hA65Da5J091575@repoman.freebsd.org>
>
>             Sam Leffler <sam@freebsd.org> writes:
> : 	diff reduction against head
> : -		SIS_UNLOCK(sc);
> :  		(*ifp->if_input)(ifp, m);
> : -		SIS_LOCK(sc);
>
> does this mean that we can call if_input with our locks held?

sis's lock is setup MTX_RECURSE in which case re-entry is handled.  You only 
need to release the lock when you may be re-entered and it's not setup as 
recursive.  I think recursive locks are bad but so long as the driver is 
setup to use them I'm not releasing them when calling up.

	Sam