Re: 2.6.15-rt3 + Open Posix Test Suite

From: Daniel Walker
Date: Wed Jan 11 2006 - 09:39:45 EST


On Tue, 2006-01-10 at 22:53 -0500, Steven Rostedt wrote:

>
> This runs a while loop at SCHED_FIFO prio 99? And alarm never happens.
> Doesn't the alarm get activated by the softirqd that is running at a
> lower priority? Seems that this is starving out the softirq from
> getting the alarm.

I thought alarm was a signal (SIGALRM) ? If it's delivered by softirqd
then this makes sense. Your right , it's softirqd related.

The processes also calls yield() inside it's while loop . We have
warnings about yield() and RT tasks.

> I believe that Thomas once had priorities attached to the timers. I'd
> like to see that again, and may even start adding them myself, such that
> when a process activates a timer, when that timer goes off, the softirq
> will get the priority of the timer. But this has some complications to
> be sorted out.

Yes, I remember . Do we fix the test in this case, or the kernel ?

Daniel

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