Re: [RFC -v2 PATCH 2/3] sched: add yield_to function

Mike Galbraith
2010-12-18T19:13:49Z

On Sat, 2010-12-18 at 19:08 +0200, Avi Kivity wrote:
> On 12/17/2010 09:15 AM, Mike Galbraith wrote:
> > BTW, with this vruntime donation thingy, what prevents a task from
> > forking off accomplices who do nothing but wait for a wakeup and
> > yield_to(exploit)?
> >
>
> What's the difference between that and forking off accomplices who
> run(exploit) directly?

The clock still advances. What I described is a clock stopper.

> Many threads dominating the scheduler has been solved by group
> scheduling. We need to make sure directed yield doesn't violate that,
> but I don't see new problems.

Let it become possible to stop clocks, and you surely will :)

-Mike