locking in a device driver

Dinesh Nair dinesh at alphaque.com
Thu Oct 27 09:46:20 PDT 2005


On 10/27/05 22:00 Scott Long said the following:
> are doing.  Other than that, there likely isn't anything that you need
> to do for 'locking' in 4.x.  The kernel is non-reentrant there, so you
> don't need to worry about synchronizing multiple threads.

thanx a bunch, scott. it's been a nightmare trying to debug the driver and 
to try to find out why the driver compiled from the same source tree works 
on freebsd 5.x and doesnt work at all on freebsd 4.x . so far, i've been 
gloriously unsuccesful at this, and am getting at my wits end on what to go 
look at.

the userland application uses pthreads, and works like a charm both on 4.x 
and 5.x without using the device. however, when the device is used, it 
somehow has synchronization errors on 4.x, leading to timers (created in 
the userland app) timing out and the like.

-- 
Regards,                           /\_/\   "All dogs go to heaven."
dinesh at alphaque.com                (0 0)    http://www.alphaque.com/
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