Re: v2.6.21-rt2

[Ingo Molnar]

* Daniel Walker <dwalker@xxxxxxxxxx> wrote:

> I don't know. irqs_off_preempt_count() could get used someplace else, 
> where you would want to flip the preempt_count() check .. It seems 
> sane to combine your patch with mine ..
> 
> irqs_off_preempt_count() (!__get_cpu_var(trace_cpu_idle) && 
> preempt_count())
> 
> You can't call __get_cpu_var() without the a positive preempt_count(), 
> so the check seems backwards regardless of the other factors ..

yeah. The whole trace_preempt_enter_idle() thing looks a bit suspect. 
Why cannot those architectures simply disable/enable preemption and get 
the same effect? It's not like we ever want to allow the preemption of 
the idle task.

and once that is solved, irqs_off_preempt_count() can again include the 
hardirq and preempt count check only and doesnt have to check the 
idle_cpu flag. This would make the whole thing simpler and would avoid 
silly bugs like this.

	Ingo
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