diff options
| -rw-r--r-- | include/linux/sched.h | 4 | ||||
| -rw-r--r-- | kernel/sched.c | 82 | ||||
| -rw-r--r-- | kernel/sched_fair.c | 8 | ||||
| -rw-r--r-- | kernel/sched_idletask.c | 4 | ||||
| -rw-r--r-- | kernel/sched_rt.c | 9 |
5 files changed, 58 insertions, 49 deletions
diff --git a/include/linux/sched.h b/include/linux/sched.h index 17249fae5014..24bce423f10d 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -866,11 +866,11 @@ struct sched_class { struct task_struct * (*pick_next_task) (struct rq *rq, u64 now); void (*put_prev_task) (struct rq *rq, struct task_struct *p, u64 now); - int (*load_balance) (struct rq *this_rq, int this_cpu, + unsigned long (*load_balance) (struct rq *this_rq, int this_cpu, struct rq *busiest, unsigned long max_nr_move, unsigned long max_load_move, struct sched_domain *sd, enum cpu_idle_type idle, - int *all_pinned, unsigned long *total_load_moved); + int *all_pinned); void (*set_curr_task) (struct rq *rq); void (*task_tick) (struct rq *rq, struct task_struct *p); diff --git a/kernel/sched.c b/kernel/sched.c index 4680f52974e3..42029634ef5a 100644 --- a/kernel/sched.c +++ b/kernel/sched.c @@ -2231,32 +2231,49 @@ out: } /* - * move_tasks tries to move up to max_nr_move tasks and max_load_move weighted - * load from busiest to this_rq, as part of a balancing operation within - * "domain". Returns the number of tasks moved. + * move_tasks tries to move up to max_load_move weighted load from busiest to + * this_rq, as part of a balancing operation within domain "sd". + * Returns 1 if successful and 0 otherwise. * * Called with both runqueues locked. */ static int move_tasks(struct rq *this_rq, int this_cpu, struct rq *busiest, - unsigned long max_nr_move, unsigned long max_load_move, + unsigned long max_load_move, struct sched_domain *sd, enum cpu_idle_type idle, int *all_pinned) { struct sched_class *class = sched_class_highest; - unsigned long load_moved, total_nr_moved = 0, nr_moved; - long rem_load_move = max_load_move; + unsigned long total_load_moved = 0; do { - nr_moved = class->load_balance(this_rq, this_cpu, busiest, - max_nr_move, (unsigned long)rem_load_move, - sd, idle, all_pinned, &load_moved); - total_nr_moved += nr_moved; - max_nr_move -= nr_moved; - rem_load_move -= load_moved; + total_load_moved += + class->load_balance(this_rq, this_cpu, busiest, + ULONG_MAX, max_load_move - total_load_moved, + sd, idle, all_pinned); class = class->next; - } while (class && max_nr_move && rem_load_move > 0); + } while (class && max_load_move > total_load_moved); - return total_nr_moved; + return total_load_moved > 0; +} + +/* + * move_one_task tries to move exactly one task from busiest to this_rq, as + * part of active balancing operations within "domain". + * Returns 1 if successful and 0 otherwise. + * + * Called with both runqueues locked. + */ +static int move_one_task(struct rq *this_rq, int this_cpu, struct rq *busiest, + struct sched_domain *sd, enum cpu_idle_type idle) +{ + struct sched_class *class; + + for (class = sched_class_highest; class; class = class->next) + if (class->load_balance(this_rq, this_cpu, busiest, + 1, ULONG_MAX, sd, idle, NULL)) + return 1; + + return 0; } /* @@ -2588,11 +2605,6 @@ find_busiest_queue(struct sched_group *group, enum cpu_idle_type idle, */ #define MAX_PINNED_INTERVAL 512 -static inline unsigned long minus_1_or_zero(unsigned long n) -{ - return n > 0 ? n - 1 : 0; -} - /* * Check this_cpu to ensure it is balanced within domain. Attempt to move * tasks if there is an imbalance. @@ -2601,7 +2613,7 @@ static int load_balance(int this_cpu, struct rq *this_rq, struct sched_domain *sd, enum cpu_idle_type idle, int *balance) { - int nr_moved, all_pinned = 0, active_balance = 0, sd_idle = 0; + int ld_moved, all_pinned = 0, active_balance = 0, sd_idle = 0; struct sched_group *group; unsigned long imbalance; struct rq *busiest; @@ -2642,18 +2654,17 @@ redo: schedstat_add(sd, lb_imbalance[idle], imbalance); - nr_moved = 0; + ld_moved = 0; if (busiest->nr_running > 1) { /* * Attempt to move tasks. If find_busiest_group has found * an imbalance but busiest->nr_running <= 1, the group is - * still unbalanced. nr_moved simply stays zero, so it is + * still unbalanced. ld_moved simply stays zero, so it is * correctly treated as an imbalance. */ local_irq_save(flags); double_rq_lock(this_rq, busiest); - nr_moved = move_tasks(this_rq, this_cpu, busiest, - minus_1_or_zero(busiest->nr_running), + ld_moved = move_tasks(this_rq, this_cpu, busiest, imbalance, sd, idle, &all_pinned); double_rq_unlock(this_rq, busiest); local_irq_restore(flags); @@ -2661,7 +2672,7 @@ redo: /* * some other cpu did the load balance for us. */ - if (nr_moved && this_cpu != smp_processor_id()) + if (ld_moved && this_cpu != smp_processor_id()) resched_cpu(this_cpu); /* All tasks on this runqueue were pinned by CPU affinity */ @@ -2673,7 +2684,7 @@ redo: } } - if (!nr_moved) { + if (!ld_moved) { schedstat_inc(sd, lb_failed[idle]); sd->nr_balance_failed++; @@ -2722,10 +2733,10 @@ redo: sd->balance_interval *= 2; } - if (!nr_moved && !sd_idle && sd->flags & SD_SHARE_CPUPOWER && + if (!ld_moved && !sd_idle && sd->flags & SD_SHARE_CPUPOWER && !test_sd_parent(sd, SD_POWERSAVINGS_BALANCE)) return -1; - return nr_moved; + return ld_moved; out_balanced: schedstat_inc(sd, lb_balanced[idle]); @@ -2757,7 +2768,7 @@ load_balance_newidle(int this_cpu, struct rq *this_rq, struct sched_domain *sd) struct sched_group *group; struct rq *busiest = NULL; unsigned long imbalance; - int nr_moved = 0; + int ld_moved = 0; int sd_idle = 0; int all_pinned = 0; cpumask_t cpus = CPU_MASK_ALL; @@ -2792,12 +2803,11 @@ redo: schedstat_add(sd, lb_imbalance[CPU_NEWLY_IDLE], imbalance); - nr_moved = 0; + ld_moved = 0; if (busiest->nr_running > 1) { /* Attempt to move tasks */ double_lock_balance(this_rq, busiest); - nr_moved = move_tasks(this_rq, this_cpu, busiest, - minus_1_or_zero(busiest->nr_running), + ld_moved = move_tasks(this_rq, this_cpu, busiest, imbalance, sd, CPU_NEWLY_IDLE, &all_pinned); spin_unlock(&busiest->lock); @@ -2809,7 +2819,7 @@ redo: } } - if (!nr_moved) { + if (!ld_moved) { schedstat_inc(sd, lb_failed[CPU_NEWLY_IDLE]); if (!sd_idle && sd->flags & SD_SHARE_CPUPOWER && !test_sd_parent(sd, SD_POWERSAVINGS_BALANCE)) @@ -2817,7 +2827,7 @@ redo: } else sd->nr_balance_failed = 0; - return nr_moved; + return ld_moved; out_balanced: schedstat_inc(sd, lb_balanced[CPU_NEWLY_IDLE]); @@ -2905,8 +2915,8 @@ static void active_load_balance(struct rq *busiest_rq, int busiest_cpu) if (likely(sd)) { schedstat_inc(sd, alb_cnt); - if (move_tasks(target_rq, target_cpu, busiest_rq, 1, - ULONG_MAX, sd, CPU_IDLE, NULL)) + if (move_one_task(target_rq, target_cpu, busiest_rq, + sd, CPU_IDLE)) schedstat_inc(sd, alb_pushed); else schedstat_inc(sd, alb_failed); diff --git a/kernel/sched_fair.c b/kernel/sched_fair.c index 9f401588d509..7307a37cf26f 100644 --- a/kernel/sched_fair.c +++ b/kernel/sched_fair.c @@ -944,11 +944,11 @@ static int cfs_rq_best_prio(struct cfs_rq *cfs_rq) return p->prio; } -static int +static unsigned long load_balance_fair(struct rq *this_rq, int this_cpu, struct rq *busiest, unsigned long max_nr_move, unsigned long max_load_move, struct sched_domain *sd, enum cpu_idle_type idle, - int *all_pinned, unsigned long *total_load_moved) + int *all_pinned) { struct cfs_rq *busy_cfs_rq; unsigned long load_moved, total_nr_moved = 0, nr_moved; @@ -1006,9 +1006,7 @@ load_balance_fair(struct rq *this_rq, int this_cpu, struct rq *busiest, break; } - *total_load_moved = max_load_move - rem_load_move; - - return total_nr_moved; + return max_load_move - rem_load_move; } /* diff --git a/kernel/sched_idletask.c b/kernel/sched_idletask.c index 41841e741c4a..1d8d9e13d950 100644 --- a/kernel/sched_idletask.c +++ b/kernel/sched_idletask.c @@ -37,11 +37,11 @@ static void put_prev_task_idle(struct rq *rq, struct task_struct *prev, u64 now) { } -static int +static unsigned long load_balance_idle(struct rq *this_rq, int this_cpu, struct rq *busiest, unsigned long max_nr_move, unsigned long max_load_move, struct sched_domain *sd, enum cpu_idle_type idle, - int *all_pinned, unsigned long *total_load_moved) + int *all_pinned) { return 0; } diff --git a/kernel/sched_rt.c b/kernel/sched_rt.c index 002fcf8d3f64..2b0626a43cb8 100644 --- a/kernel/sched_rt.c +++ b/kernel/sched_rt.c @@ -172,15 +172,16 @@ static struct task_struct *load_balance_next_rt(void *arg) return p; } -static int +static unsigned long load_balance_rt(struct rq *this_rq, int this_cpu, struct rq *busiest, unsigned long max_nr_move, unsigned long max_load_move, struct sched_domain *sd, enum cpu_idle_type idle, - int *all_pinned, unsigned long *load_moved) + int *all_pinned) { int this_best_prio, best_prio, best_prio_seen = 0; int nr_moved; struct rq_iterator rt_rq_iterator; + unsigned long load_moved; best_prio = sched_find_first_bit(busiest->rt.active.bitmap); this_best_prio = sched_find_first_bit(this_rq->rt.active.bitmap); @@ -203,11 +204,11 @@ load_balance_rt(struct rq *this_rq, int this_cpu, struct rq *busiest, rt_rq_iterator.arg = busiest; nr_moved = balance_tasks(this_rq, this_cpu, busiest, max_nr_move, - max_load_move, sd, idle, all_pinned, load_moved, + max_load_move, sd, idle, all_pinned, &load_moved, this_best_prio, best_prio, best_prio_seen, &rt_rq_iterator); - return nr_moved; + return load_moved; } static void task_tick_rt(struct rq *rq, struct task_struct *p) |