Re: [RFC patch 1/4] sched: change cfs_rq load avg to unsigned long

From: Alex Shi
Date: Mon Jun 17 2013 - 06:00:33 EST


On 06/17/2013 05:49 PM, Paul Turner wrote:
>>> >> Hi Alex,
>>> >>
>>> >> I just want to point out that we can't have more than 48388 tasks with
>>> >> highest priority on a runqueue with an unsigned long on a 32 bits
>>> >> system. I don't know if we can reach such kind of limit on a 32bits
>>> >> machine ? For sure, not on an embedded system.
> This should be ok.
>
> Note that:
> runnable_load_avg = \Sum se->load_avg_contrib <= \Sum
> se->load.weight = cfs_rq->load.weight
>
> And load_weight uses unsigned longs also.
>
> blocked_load_avg must be also safe since anything appearing in blocked
> load could have appeared in runnable load and we've said that was ok
> above.
>
> Reviewed-By: Paul Turner <pjt@xxxxxxxxxx>
>

thanks for review!

--
Thanks
Alex
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/