Messages in this thread | | | Subject | Re: [RFC][PATCH] sched: SCHED_FIFO watchdog timer | From | Peter Zijlstra <> | Date | Mon, 15 Oct 2007 15:57:42 +0200 |
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On Mon, 2007-10-15 at 15:26 +0200, Dmitry Adamushko wrote: > On 14/10/2007, Peter Zijlstra <a.p.zijlstra@chello.nl> wrote: > > The below patch is an idea proposed by tglx and depends on sched-devel + > > the hrtick patch previously posted. > > > > The current watchdog action is to demote the task to SCHED_NORMAL, > > however it might be wanted to deliver a signal instead (or have more per > > task configuration state). Which is why I added Lennart to the CC list > > as I gathered he would like something like this for PulseAudio. > > > > --- > > Subject: sched: SCHED_FIFO watchdog timer > > Why only SHCED_FIFO and not SCHED_RR? > Their (mis)behavior is similar wrt SCHED_NORMAL tasks.
Because SCHED_FIFO is easier, _RR is for later. It was mostly an RFC to request behavioural wishes from the users.
> > > +#ifdef CONFIG_SCHED_HRT_TICK > > +static int fifo_watchdog(struct rq *rq, struct task_struct *p, int queued) > > +{ > > + if (likely(!queued || p->policy != SCHED_FIFO)) > > + return 0; > > + > > + /* > > + * task has been naughty, turn into SCHED_NORMAL > > + */ > > + printk(KERN_INFO "SCHED_FIFO task %s/%d exceeded his runtime quota," > > + " demoting to regular task\n", p->comm, task_pid_nr(p)); > > + deactivate_task(rq, p, 0); > > + __setscheduler(rq, p, SCHED_NORMAL, 0); > > + activate_task(rq, p, 0); > > + resched_task(p); > > I guess, put_prev_task() / set_curr_task() should be called (for the > case of task_running(p)) to make it group-scheduler-friendly (as it's > done e.g. in sched_setscheduler()). > > (normilize_task() should probably do the same)
Right, that is where I copied from, I'll pull the functionality into a single function and make this and the sysrq stuff use it.
Thanks! [unhandled content-type:application/pgp-signature] | |