(No subject header)

From: Milton Miller
Date: Thu May 27 2010 - 01:25:35 EST



[Hmm, why did this not appear in patchwork.kernel.org? Now
I have to guess a CC list.]

On Wed, 26 May 2010 around 22:43:50 -0400 (EDT), Len Brown wrote:
> From: Len Brown <len.brown@xxxxxxxxx>
>
> TS_POLLING set tells the scheduler a task will poll
> need_resched() to look for work.
>

True

> TS_POLLING clear tells resched_task() and wake_up_idle_cpu()
> that the remote CPU is sleeping in idle, and thus requires
> a reschedule interrupt to wake them to notice work.

No, that only applies to the idle task.


>
> Update the description of TS_POLLING to reflect how it works.
> "cleared when sleeping in idle, requiring reschedule interrupt"

That would imply its set for every normal task that is not in some
kind of sleep state.


>
> Signed-off-by: Len Brown <len.brown@xxxxxxxxx>
> Acked-by: Peter Zijlstra <peterz@xxxxxxxxxxxxx>

> -#define TS_POLLING 0x0004 /* true if in idle loop
> - and not sleeping */
> +#define TS_POLLING 0x0004 /* clear when sleeping in idle
> + requiring reschedule interrupt */

How about "idle task polling need_resched, skip sending interrupt"?

milton
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