Messages in this thread | | | Date | Fri, 21 Apr 2017 10:39:26 +0100 | From | Juri Lelli <> | Subject | Re: [PATCH] sched/deadline: fix switching to -deadline |
| |
Hi Luca,
On 20/04/17 21:30, Luca Abeni wrote: > From: Luca Abeni <luca.abeni@santannapisa.it> > > When switching to -deadline, if the scheduling deadline of a task is > in the past then switched_to_dl() calls setup_new_entity() to properly > initialize the scheduling deadline and runtime. > > The problem is that the task is enqueued _before_ having its parameters > initialized by setup_new_entity(), and this can cause problems. > For example, a task with its out-of-date deadline in the past will > potentially be enqueued as the highest priority one; however, its > adjusted deadline may not be the earliest one. > > This patch fixes the problem by initializing the task's parameters before > enqueuing it. > > Signed-off-by: Luca Abeni <luca.abeni@santannapisa.it> > Reviewed-by: Daniel Bristot de Oliveira <bristot@redhat.com> > --- > kernel/sched/deadline.c | 12 ++++-------- > 1 file changed, 4 insertions(+), 8 deletions(-) > > diff --git a/kernel/sched/deadline.c b/kernel/sched/deadline.c > index a2ce590..ec53d24 100644 > --- a/kernel/sched/deadline.c > +++ b/kernel/sched/deadline.c > @@ -950,6 +950,10 @@ enqueue_dl_entity(struct sched_dl_entity *dl_se, > update_dl_entity(dl_se, pi_se); > else if (flags & ENQUEUE_REPLENISH) > replenish_dl_entity(dl_se, pi_se); > + else if ((flags & ENQUEUE_RESTORE) &&
Not sure I understand how this works. AFAICT we are doing __sched_setscheduler() when we want to catch the case of a new dl_entity (SCHED_{OTHER,FIFO} -> SCHED_DEADLINE}, but queue_flags (which are passed to enqueue_task()) don't seem to have ENQUEUE_RESTORE set?
Thanks,
- Juri
| |