Re: [Openipmi-developer] modprobe ipmi_si hangs under 2.6.30-rc5

[Corey Minyard]

Ferenc Wagner wrote:
> Corey Minyard <minyard@xxxxxxx> writes:
>
>   
> > I know what is happening now.  Can you try the attached patch?  I'm
> > disabling the requeue and discarding the message when an IPMB message
> > is received before everything is initialized.  If you don't, the code
> > will not deliver any messages because something is already in the
> > queue.
> >     
>
> Yep, that fixed it, modprobe runs through now!
>   
Thanks for testing this.

>   
> > Ferenc Wagner wrote:
> >
> >     
> > > My concern is that it does something too often, not letting the CPU
> > > enter deep sleep states, perhaps.  Or is that also an artifact of
> > > debugging?
> > >       
> > No, it's an artifact of a lousy hardware interface.  Very few IPMI
> > interfaces support interrupts, so they have to be polled :(.
> >     
>
> I'd say this isn't an artifact but the sad truth itself.  Just out of
> interest, how often does the driver wake up to check the inteface?
>   
I'd have to agree.

When idle, the driver wakes up every 10ms to check for something on the 
driver.  When a message is in transit, it's every jiffie.

-corey
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