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Date: Mon, 02 Jun 2008 11:34:53 -0400
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From: "George V. Neville-Neil" <gnn@neville-neil.com>
To: Julian Elischer <julian@elischer.org>
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Cc: arch@freebsd.org, Ed Schouten <ed@80386.nl>
Subject: Re: all mutexes -> read-write locks?
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At Mon, 02 Jun 2008 00:11:02 -0700,
julian wrote:
> 
> Daniel Eischen wrote:
> > I'd rather not.  What do you have against them?  
> 
> People use them without thinking about whether they need to be so
> strict.

This is an age old problem that removing mutexes will never fix.  We
could add documentation to the manual pages though saying, "Do you
really really need this?"

> > Their API is simple enough to use.  If there is code that really
> > wants to have multiple readers, by all means change it to use
> > rwlocks.
> 
> 
> yes but we have a lot of code that uses mutexes.. changing it would 
> allow a slow transition to using rw locks.

We will likely have to do that ourselves.

Sorry, but this is a Sisyphean task, and removing mutexes will not
prevent the rock from falling back upon us again.

Best,
George