From 810b38179e9e4d4f57b4b733767bb08f8291a965 Mon Sep 17 00:00:00 2001 From: Peter Zijlstra Date: Fri, 29 Feb 2008 15:21:01 -0500 Subject: [PATCH] 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 Signed-off-by: Peter Zijlstra Signed-off-by: Ingo Molnar --- include/linux/sched.h | 4 ++++ kernel/sched.c | 5 +++++ kernel/sched_fair.c | 14 ++++++++++++++ 3 files changed, 23 insertions(+) diff --git a/include/linux/sched.h b/include/linux/sched.h index 9ae4030067a9..11d8e9a74eff 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -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 { diff --git a/kernel/sched.c b/kernel/sched.c index dcd553cc4ee8..0b949c4e73ad 100644 --- a/kernel/sched.c +++ b/kernel/sched.c @@ -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); diff --git a/kernel/sched_fair.c b/kernel/sched_fair.c index 3df4d46994ca..e2a530515619 100644 --- a/kernel/sched_fair.c +++ b/kernel/sched_fair.c @@ -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 -- 2.20.1