RE: rw_lock vs mutex

[Paul Goyette <paul%whooppee.com@localhost>]

On Thu, 2 Feb 2012, Paul_Koning%Dell.com@localhost wrote:

> A rw_lock allows multiple readers, correct?  If there's a non-trivial 
> probability of concurrent reads that would make a difference.  If not, 
> then a mutex would be just as good especially if that is lower 
> overhead.

The rwlock in question is contained with the driver's softc.  The only 
exported accessors are i2c_bus_acquire() (which grabs a RW_WRITER lock) 
and i2c_bus_release().

A mutex makes much more sense.


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