Re: NIC inerrupt

From: Axel Weiß
Date: Tue Apr 20 2004 - 09:05:37 EST


Am Montag, 19. April 2004 14:46 schrieb John Que:
> Hello,
>
> I want to count the number of times I reach an NIC receive
> interrupt.
>
> I added a global static variable of type int , and initialized
> it to 0 ; each time I am in the rx_interrupt of the card I incerement
> it by one;
> I got large , non sensible numbers after one or two seconds;
>
> So for debug I added printk each time I increment it in rx_interrupt.
>
> What I see is that there are unreasonable jumps in the number
>
> for instance , it inceremnts sequntially from 1 to 80,then jums to 4500,
> increments a little sequentially to 4580, and the jums again to
> 11000 ;
>
> Is it got to do with it that this is in interrupt?
> Any idea what it can be ?
>
>
> (I also tried to declare it as static in the rx_interrupt method
> and the same happened)

Probably you didn't declare your count variable 'volatile'?

Axel

--
Humboldt-Universität zu Berlin
Institut für Informatik
Signalverarbeitung und Mustererkennung
Dipl.-Inf. Axel Weiß
Rudower Chaussee 25
12489 Berlin-Adlershof
+49-30-2093-3050

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