Re: [parisc-linux] [PATCH] PDC cleanup and encapsulation

[Ryan Bradetich <rbrad@beavis.ybsoft.com>]

On Thu, Mar 29, 2001 at 10:48:26AM -0700, Paul Bame wrote:
> 
> I wonder if it makes sense to pass the lock to mem_pdc_call and let
> it do the lock/unlock rather than doing that in every caller to
> mem_pdc_call.
> 
> 	-P

This could be a possible option.  I chose not to do something similar
to do this for two reasons:

	1. The PDC call can determine the lock level (ie. spin_lock_irq()
           or spin_lock_irqsave()) depending upon if the PDC call can
           be made in interrupt context.

	2. Since pdc_result and pdc_result2 are globals, I used the
	   spin_lock to protect these variables.  That is why the
	   convert_to_wide() calls, etc are contained within the 
	   spin lock.

Maybe I was being paranoid about the locking, and your approach makes
more sense.  I was more interested in protecting data then holding
the lock for the minimum time so my approach might be draconian.  I
do not understand all the locking issues, but I'd be willing to
modify the code to put the lock in the mem_pdc_call if others agree.

Thanks,

- Ryan