Re: sched: fix/optimise some issues

From: Peter Zijlstra
Date: Wed Jul 20 2011 - 15:12:05 EST

On Wed, 2011-07-20 at 15:42 +0200, Stephan BÃrwolf wrote:
> In "check_preempt_tick()" (kernel/sched_fair.c:1093) a ulong
> called "ideal_runtime" stores a timeslice of the current task
> (scheduling entity). This time complies real cpu-time.
> At the end of the same function (nr_running > 1) this (real) time
> is compared with a virtual-runtime-delta. Obviously the timeunits
> (real vs. virtual) didn't fit.
> Using "wakeup_preempt_entity()" instead should fix this in a even
> more general way.

Hrm,. I'm fairly sure we did that on purpose and the thing that is
missing is a big fat comment. People keep trying to fix that (me

I'll try and dig up the why and such.
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at
Please read the FAQ at