From: Byungchul Park <[email protected]> set_task_rq() which is a commonly used function regardless of sched class is currently assigning both cfs_rq for fair class and rt_rq for rt class to a task. but it would be better that a class related operation is done by its own class respectively. additionally, this patch moves some code's position to refer for_each_class() macro.
Signed-off-by: Byungchul Park <[email protected]> --- kernel/sched/fair.c | 9 ++++ kernel/sched/rt.c | 14 ++++++ kernel/sched/sched.h | 120 ++++++++++++++++++++++++-------------------------- 3 files changed, 80 insertions(+), 63 deletions(-) diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index 077076f..07882c2 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -8088,6 +8088,14 @@ static void task_move_group_fair(struct task_struct *p) attach_task_cfs_rq(p); } +static void set_task_rq_fair(struct task_struct *p, unsigned int cpu) +{ + struct task_group *tg = task_group(p); + + p->se.cfs_rq = tg->cfs_rq[cpu]; + p->se.parent = tg->se[cpu]; +} + void free_fair_sched_group(struct task_group *tg) { int i; @@ -8306,6 +8314,7 @@ const struct sched_class fair_sched_class = { #ifdef CONFIG_FAIR_GROUP_SCHED .task_move_group = task_move_group_fair, + .set_task_rq = set_task_rq_fair, #endif }; diff --git a/kernel/sched/rt.c b/kernel/sched/rt.c index e3cc163..f1a1320 100644 --- a/kernel/sched/rt.c +++ b/kernel/sched/rt.c @@ -2143,6 +2143,16 @@ static void switched_to_rt(struct rq *rq, struct task_struct *p) } } +#ifdef CONFIG_RT_GROUP_SCHED +static void set_task_rq_rt(struct task_struct *p, unsigned int cpu) +{ + struct task_group *tg = task_group(p); + + p->rt.rt_rq = tg->rt_rq[cpu]; + p->rt.parent = tg->rt_se[cpu]; +} +#endif + /* * Priority of the task has changed. This may cause * us to initiate a push or pull. @@ -2290,6 +2300,10 @@ const struct sched_class rt_sched_class = { .switched_to = switched_to_rt, .update_curr = update_curr_rt, + +#ifdef CONFIG_RT_GROUP_SCHED + .set_task_rq = set_task_rq_rt, +#endif }; #ifdef CONFIG_SCHED_DEBUG diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h index af6f252..7f73e89 100644 --- a/kernel/sched/sched.h +++ b/kernel/sched/sched.h @@ -905,69 +905,6 @@ static inline void sched_ttwu_pending(void) { } #include "stats.h" #include "auto_group.h" -#ifdef CONFIG_CGROUP_SCHED - -/* - * Return the group to which this tasks belongs. - * - * We cannot use task_css() and friends because the cgroup subsystem - * changes that value before the cgroup_subsys::attach() method is called, - * therefore we cannot pin it and might observe the wrong value. - * - * The same is true for autogroup's p->signal->autogroup->tg, the autogroup - * core changes this before calling sched_move_task(). - * - * Instead we use a 'copy' which is updated from sched_move_task() while - * holding both task_struct::pi_lock and rq::lock. - */ -static inline struct task_group *task_group(struct task_struct *p) -{ - return p->sched_task_group; -} - -/* Change a task's cfs_rq and parent entity if it moves across CPUs/groups */ -static inline void set_task_rq(struct task_struct *p, unsigned int cpu) -{ -#if defined(CONFIG_FAIR_GROUP_SCHED) || defined(CONFIG_RT_GROUP_SCHED) - struct task_group *tg = task_group(p); -#endif - -#ifdef CONFIG_FAIR_GROUP_SCHED - p->se.cfs_rq = tg->cfs_rq[cpu]; - p->se.parent = tg->se[cpu]; -#endif - -#ifdef CONFIG_RT_GROUP_SCHED - p->rt.rt_rq = tg->rt_rq[cpu]; - p->rt.parent = tg->rt_se[cpu]; -#endif -} - -#else /* CONFIG_CGROUP_SCHED */ - -static inline void set_task_rq(struct task_struct *p, unsigned int cpu) { } -static inline struct task_group *task_group(struct task_struct *p) -{ - return NULL; -} - -#endif /* CONFIG_CGROUP_SCHED */ - -static inline void __set_task_cpu(struct task_struct *p, unsigned int cpu) -{ - set_task_rq(p, cpu); -#ifdef CONFIG_SMP - /* - * After ->cpu is set up to a new value, task_rq_lock(p, ...) can be - * successfuly executed on another CPU. We must ensure that updates of - * per-task data have been completed by this moment. - */ - smp_wmb(); - task_thread_info(p)->cpu = cpu; - p->wake_cpu = cpu; -#endif -} - /* * Tunables that become constants when CONFIG_SCHED_DEBUG is off: */ @@ -1222,6 +1159,8 @@ struct sched_class { #ifdef CONFIG_FAIR_GROUP_SCHED void (*task_move_group) (struct task_struct *p); #endif + + void (*set_task_rq) (struct task_struct *p, unsigned int cpu); }; static inline void put_prev_task(struct rq *rq, struct task_struct *prev) @@ -1239,6 +1178,61 @@ extern const struct sched_class rt_sched_class; extern const struct sched_class fair_sched_class; extern const struct sched_class idle_sched_class; +#ifdef CONFIG_CGROUP_SCHED + +/* + * Return the group to which this tasks belongs. + * + * We cannot use task_css() and friends because the cgroup subsystem + * changes that value before the cgroup_subsys::attach() method is called, + * therefore we cannot pin it and might observe the wrong value. + * + * The same is true for autogroup's p->signal->autogroup->tg, the autogroup + * core changes this before calling sched_move_task(). + * + * Instead we use a 'copy' which is updated from sched_move_task() while + * holding both task_struct::pi_lock and rq::lock. + */ +static inline struct task_group *task_group(struct task_struct *p) +{ + return p->sched_task_group; +} + +/* Change a task's cfs_rq and parent entity if it moves across CPUs/groups */ +static inline void set_task_rq(struct task_struct *p, unsigned int cpu) +{ + const struct sched_class *class; + + for_each_class(class) { + if (class->set_task_rq) + class->set_task_rq(p, cpu); + } +} + +#else /* CONFIG_CGROUP_SCHED */ + +static inline void set_task_rq(struct task_struct *p, unsigned int cpu) { } +static inline struct task_group *task_group(struct task_struct *p) +{ + return NULL; +} + +#endif /* CONFIG_CGROUP_SCHED */ + +static inline void __set_task_cpu(struct task_struct *p, unsigned int cpu) +{ + set_task_rq(p, cpu); +#ifdef CONFIG_SMP + /* + * After ->cpu is set up to a new value, task_rq_lock(p, ...) can be + * successfuly executed on another CPU. We must ensure that updates of + * per-task data have been completed by this moment. + */ + smp_wmb(); + task_thread_info(p)->cpu = cpu; + p->wake_cpu = cpu; +#endif +} #ifdef CONFIG_SMP -- 1.7.9.5 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
