sched: retain vruntime

Kei Tokunaga reported an interactivity problem when moving tasks
between control groups.

Tasks would retain their old vruntime when moved between groups, this
can cause funny lags. Re-set the vruntime on group move to fit within
the new tree.

Reported-by: Kei Tokunaga <tokunaga.keiich@jp.fujitsu.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This commit is contained in:
Peter Zijlstra 2008-02-29 15:21:01 -05:00 committed by Ingo Molnar
parent ce4796d1e1
commit 810b38179e
3 changed files with 23 additions and 0 deletions

View file

@ -899,6 +899,10 @@ struct sched_class {
int running);
void (*prio_changed) (struct rq *this_rq, struct task_struct *task,
int oldprio, int running);
#ifdef CONFIG_FAIR_GROUP_SCHED
void (*moved_group) (struct task_struct *p);
#endif
};
struct load_weight {

View file

@ -7625,6 +7625,11 @@ void sched_move_task(struct task_struct *tsk)
set_task_rq(tsk, task_cpu(tsk));
#ifdef CONFIG_FAIR_GROUP_SCHED
if (tsk->sched_class->moved_group)
tsk->sched_class->moved_group(tsk);
#endif
if (on_rq) {
if (unlikely(running))
tsk->sched_class->set_curr_task(rq);

View file

@ -1353,6 +1353,16 @@ static void set_curr_task_fair(struct rq *rq)
set_next_entity(cfs_rq_of(se), se);
}
#ifdef CONFIG_FAIR_GROUP_SCHED
static void moved_group_fair(struct task_struct *p)
{
struct cfs_rq *cfs_rq = task_cfs_rq(p);
update_curr(cfs_rq);
place_entity(cfs_rq, &p->se, 1);
}
#endif
/*
* All the scheduling class methods:
*/
@ -1381,6 +1391,10 @@ static const struct sched_class fair_sched_class = {
.prio_changed = prio_changed_fair,
.switched_to = switched_to_fair,
#ifdef CONFIG_FAIR_GROUP_SCHED
.moved_group = moved_group_fair,
#endif
};
#ifdef CONFIG_SCHED_DEBUG