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Date: Wed, 21 Jun 2006 02:44:19 +0400 (MSD)
From: Maxim Konovalov <maxim@macomnet.ru>
To: Scott Long <scottl@samsco.org>
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Cc: cvs-src@FreeBSD.org, src-committers@FreeBSD.org, cvs-all@FreeBSD.org
Subject: Re: cvs commit: src/share/man/man9 lock.9
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[...]
> > > >Btw, as I see there are not many consumers of lock.9
> > > >infrastructure comparing to mutex.9, sx.9 etc in our tree.  Is
> > > >it something derecated?
> > > >
> > >
> > >I guess that VFS doesn't count as being important?
> >
> >
> > As an average user I just want to know what pros and contras for
> > using lock.9 vs all other locking primitivies.  It is not clear
> > from our man pages and arch book.  Sorry if I'm asking something
> > completely stupid.
> >
>
> lockmgr is somewhat analogous to an SX lock.  However, due to some
> of the special considerations needed by VFS in terms of the vnode
> life cycle and blocking for I/O, they aren't completely functionally
> equivalent to an SX lock.  It would be nice to fix VFS to not need
> these special considerations, but that is a very complicated and
> risky task.

Thanks!

-- 
Maxim Konovalov