[PATCH] ppc32: fix cpm_uart_int() missing interrupts

[Guillaume Autran]

You are right, moving the event clearing statement is much easier and 
cleaner. Let the interrupt be the loop.
Thanks Dan !


Dan Malek wrote:

>
> On May 19, 2005, at 3:34 PM, Guillaume Autran wrote:
>
>> Is it better like this ?
>
>
> Yes, but now I see one problem with it.  :-)
>
> We have to clear all events even though we may not
> handle all of them.  Your while loop filters only the events
> we process, but there could be others causing the interrupt
> which will never get cleared.  In this case we end up with
> an infinite interrupt loop where we don't process anything,
> but we don't make the interrupt go away, either.   It may be
> easier to forget the loop, just read/clear the event register
> up front, then process based on the events based upon
> what we found. It's what we tend to do in the other drivers.
>
> The functions called to do the rx/tx processing have loops
> in them to process all of the data they find, so it isn't likely
> you have left anything behind.  If you want to try to save
> the interrupt overhead, change it to do/while, check again
> at the end before the exit.
>
> Thanks.
>
>
>     -- Dan
>

-- 
=======================================
Guillaume Autran
Senior Software Engineer
MRV Communications, Inc.
Tel: (978) 952-4932 office
E-mail: gautran at mrv.com
======================================= 

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