In preparation of further separating pick_next_task() and set_curr_task() we have to pass the actual task into it, while there, rename the thing to better pair with put_prev_task().
Signed-off-by: Peter Zijlstra (Intel) <pet...@infradead.org> --- kernel/sched/core.c | 12 ++++++------ kernel/sched/deadline.c | 7 +------ kernel/sched/fair.c | 17 ++++++++++++++--- kernel/sched/idle.c | 27 +++++++++++++++------------ kernel/sched/rt.c | 7 +------ kernel/sched/sched.h | 8 +++++--- kernel/sched/stop_task.c | 17 +++++++---------- 7 files changed, 49 insertions(+), 46 deletions(-) --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -1494,7 +1494,7 @@ void do_set_cpus_allowed(struct task_str if (queued) enqueue_task(rq, p, ENQUEUE_RESTORE | ENQUEUE_NOCLOCK); if (running) - set_curr_task(rq, p); + set_next_task(rq, p); } /* @@ -4273,7 +4273,7 @@ void rt_mutex_setprio(struct task_struct if (queued) enqueue_task(rq, p, queue_flag); if (running) - set_curr_task(rq, p); + set_next_task(rq, p); check_class_changed(rq, p, prev_class, oldprio); out_unlock: @@ -4340,7 +4340,7 @@ void set_user_nice(struct task_struct *p resched_curr(rq); } if (running) - set_curr_task(rq, p); + set_next_task(rq, p); out_unlock: task_rq_unlock(rq, p, &rf); } @@ -4783,7 +4783,7 @@ static int __sched_setscheduler(struct t enqueue_task(rq, p, queue_flags); } if (running) - set_curr_task(rq, p); + set_next_task(rq, p); check_class_changed(rq, p, prev_class, oldprio); @@ -5972,7 +5972,7 @@ void sched_setnuma(struct task_struct *p if (queued) enqueue_task(rq, p, ENQUEUE_RESTORE | ENQUEUE_NOCLOCK); if (running) - set_curr_task(rq, p); + set_next_task(rq, p); task_rq_unlock(rq, p, &rf); } #endif /* CONFIG_NUMA_BALANCING */ @@ -6853,7 +6853,7 @@ void sched_move_task(struct task_struct if (queued) enqueue_task(rq, tsk, queue_flags); if (running) - set_curr_task(rq, tsk); + set_next_task(rq, tsk); task_rq_unlock(rq, tsk, &rf); } --- a/kernel/sched/deadline.c +++ b/kernel/sched/deadline.c @@ -1812,11 +1812,6 @@ static void task_fork_dl(struct task_str */ } -static void set_curr_task_dl(struct rq *rq) -{ - set_next_task_dl(rq, rq->curr); -} - #ifdef CONFIG_SMP /* Only try algorithms three times */ @@ -2404,6 +2399,7 @@ const struct sched_class dl_sched_class .pick_next_task = pick_next_task_dl, .put_prev_task = put_prev_task_dl, + .set_next_task = set_next_task_dl, #ifdef CONFIG_SMP .select_task_rq = select_task_rq_dl, @@ -2414,7 +2410,6 @@ const struct sched_class dl_sched_class .task_woken = task_woken_dl, #endif - .set_curr_task = set_curr_task_dl, .task_tick = task_tick_dl, .task_fork = task_fork_dl, --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -10121,9 +10121,19 @@ static void switched_to_fair(struct rq * * This routine is mostly called to set cfs_rq->curr field when a task * migrates between groups/classes. */ -static void set_curr_task_fair(struct rq *rq) +static void set_next_task_fair(struct rq *rq, struct task_struct *p) { - struct sched_entity *se = &rq->curr->se; + struct sched_entity *se = &p->se; + +#ifdef CONFIG_SMP + if (task_on_rq_queued(p)) { + /* + * Move the next running task to the front of the list, so our + * cfs_tasks list becomes MRU one. + */ + list_move(&se->group_node, &rq->cfs_tasks); + } +#endif for_each_sched_entity(se) { struct cfs_rq *cfs_rq = cfs_rq_of(se); @@ -10394,7 +10404,9 @@ const struct sched_class fair_sched_clas .check_preempt_curr = check_preempt_wakeup, .pick_next_task = pick_next_task_fair, + .put_prev_task = put_prev_task_fair, + .set_next_task = set_next_task_fair, #ifdef CONFIG_SMP .select_task_rq = select_task_rq_fair, @@ -10407,7 +10419,6 @@ const struct sched_class fair_sched_clas .set_cpus_allowed = set_cpus_allowed_common, #endif - .set_curr_task = set_curr_task_fair, .task_tick = task_tick_fair, .task_fork = task_fork_fair, --- a/kernel/sched/idle.c +++ b/kernel/sched/idle.c @@ -374,14 +374,25 @@ static void check_preempt_curr_idle(stru resched_curr(rq); } +static void put_prev_task_idle(struct rq *rq, struct task_struct *prev) +{ +} + +static void set_next_task_idle(struct rq *rq, struct task_struct *next) +{ + update_idle_core(rq); + schedstat_inc(rq->sched_goidle); +} + static struct task_struct * pick_next_task_idle(struct rq *rq, struct task_struct *prev, struct rq_flags *rf) { + struct task_struct *next = rq->idle; + put_prev_task(rq, prev); - update_idle_core(rq); - schedstat_inc(rq->sched_goidle); + set_next_task_idle(rq, next); - return rq->idle; + return next; } /* @@ -397,10 +408,6 @@ dequeue_task_idle(struct rq *rq, struct raw_spin_lock_irq(&rq->lock); } -static void put_prev_task_idle(struct rq *rq, struct task_struct *prev) -{ -} - /* * scheduler tick hitting a task of our scheduling class. * @@ -413,10 +420,6 @@ static void task_tick_idle(struct rq *rq { } -static void set_curr_task_idle(struct rq *rq) -{ -} - static void switched_to_idle(struct rq *rq, struct task_struct *p) { BUG(); @@ -451,13 +454,13 @@ const struct sched_class idle_sched_clas .pick_next_task = pick_next_task_idle, .put_prev_task = put_prev_task_idle, + .set_next_task = set_next_task_idle, #ifdef CONFIG_SMP .select_task_rq = select_task_rq_idle, .set_cpus_allowed = set_cpus_allowed_common, #endif - .set_curr_task = set_curr_task_idle, .task_tick = task_tick_idle, .get_rr_interval = get_rr_interval_idle, --- a/kernel/sched/rt.c +++ b/kernel/sched/rt.c @@ -2355,11 +2355,6 @@ static void task_tick_rt(struct rq *rq, } } -static void set_curr_task_rt(struct rq *rq) -{ - set_next_task_rt(rq, rq->curr); -} - static unsigned int get_rr_interval_rt(struct rq *rq, struct task_struct *task) { /* @@ -2381,6 +2376,7 @@ const struct sched_class rt_sched_class .pick_next_task = pick_next_task_rt, .put_prev_task = put_prev_task_rt, + .set_next_task = set_next_task_rt, #ifdef CONFIG_SMP .select_task_rq = select_task_rq_rt, @@ -2392,7 +2388,6 @@ const struct sched_class rt_sched_class .switched_from = switched_from_rt, #endif - .set_curr_task = set_curr_task_rt, .task_tick = task_tick_rt, .get_rr_interval = get_rr_interval_rt, --- a/kernel/sched/sched.h +++ b/kernel/sched/sched.h @@ -1711,6 +1711,7 @@ struct sched_class { struct task_struct *prev, struct rq_flags *rf); void (*put_prev_task)(struct rq *rq, struct task_struct *p); + void (*set_next_task)(struct rq *rq, struct task_struct *p); #ifdef CONFIG_SMP int (*select_task_rq)(struct task_struct *p, int task_cpu, int sd_flag, int flags); @@ -1725,7 +1726,6 @@ struct sched_class { void (*rq_offline)(struct rq *rq); #endif - void (*set_curr_task)(struct rq *rq); void (*task_tick)(struct rq *rq, struct task_struct *p, int queued); void (*task_fork)(struct task_struct *p); void (*task_dead)(struct task_struct *p); @@ -1755,12 +1755,14 @@ struct sched_class { static inline void put_prev_task(struct rq *rq, struct task_struct *prev) { + WARN_ON_ONCE(rq->curr != prev); prev->sched_class->put_prev_task(rq, prev); } -static inline void set_curr_task(struct rq *rq, struct task_struct *curr) +static inline void set_next_task(struct rq *rq, struct task_struct *next) { - curr->sched_class->set_curr_task(rq); + WARN_ON_ONCE(rq->curr != next); + next->sched_class->set_next_task(rq, next); } #ifdef CONFIG_SMP --- a/kernel/sched/stop_task.c +++ b/kernel/sched/stop_task.c @@ -23,6 +23,11 @@ check_preempt_curr_stop(struct rq *rq, s /* we're never preempted */ } +static void set_next_task_stop(struct rq *rq, struct task_struct *stop) +{ + stop->se.exec_start = rq_clock_task(rq); +} + static struct task_struct * pick_next_task_stop(struct rq *rq, struct task_struct *prev, struct rq_flags *rf) { @@ -32,8 +37,7 @@ pick_next_task_stop(struct rq *rq, struc return NULL; put_prev_task(rq, prev); - - stop->se.exec_start = rq_clock_task(rq); + set_next_task_stop(rq, stop); return stop; } @@ -86,13 +90,6 @@ static void task_tick_stop(struct rq *rq { } -static void set_curr_task_stop(struct rq *rq) -{ - struct task_struct *stop = rq->stop; - - stop->se.exec_start = rq_clock_task(rq); -} - static void switched_to_stop(struct rq *rq, struct task_struct *p) { BUG(); /* its impossible to change to this class */ @@ -128,13 +125,13 @@ const struct sched_class stop_sched_clas .pick_next_task = pick_next_task_stop, .put_prev_task = put_prev_task_stop, + .set_next_task = set_next_task_stop, #ifdef CONFIG_SMP .select_task_rq = select_task_rq_stop, .set_cpus_allowed = set_cpus_allowed_common, #endif - .set_curr_task = set_curr_task_stop, .task_tick = task_tick_stop, .get_rr_interval = get_rr_interval_stop,