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Subject: Re: [PATCH 4/6] sched: Do not account irq time to current task
From: Peter Zijlstra <peterz@infradead.org>
To: Venkatesh Pallipadi <venki@google.com>
Cc: Ingo Molnar <mingo@elte.hu>, "H. Peter Anvin" <hpa@zytor.com>,
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Date: Mon, 20 Sep 2010 19:38:26 +0200
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On Mon, 2010-09-20 at 10:33 -0700, Venkatesh Pallipadi wrote:
> Yes. I like your idea of having separate rq->clock and rq->clock_task.
> That will clean up this code a bit.
> We will still need to keep track of "last accounted irq time" at the
> task or rq level to account sched_rt_avg_update correctly. But, I dont
> have to play with cfs_rq and rt_rq as in this patch though. 

Ah, indeed. Ok so have rq->clock, rq->clock_task and have a
irq_time_stamp to fold stuff into sched_rt_avg_update(), then I think
you can isolate all the clock bits to update_rq_clock() and then use
->clock_task in update_curr{,_rt}().