diff options
-rw-r--r-- | kernel/sched.c | 7 | ||||
-rw-r--r-- | kernel/sched_rt.c | 57 |
2 files changed, 38 insertions, 26 deletions
diff --git a/kernel/sched.c b/kernel/sched.c index 34b7d721d73..35ef06c9921 100644 --- a/kernel/sched.c +++ b/kernel/sched.c @@ -365,6 +365,13 @@ struct root_domain { atomic_t refcount; cpumask_t span; cpumask_t online; + + /* + * The "RT overload" flag: it gets set if a CPU has more than + * one runnable RT task. + */ + cpumask_t rto_mask; + atomic_t rto_count; }; static struct root_domain def_root_domain; diff --git a/kernel/sched_rt.c b/kernel/sched_rt.c index 4d0a60e47df..b049e5110ee 100644 --- a/kernel/sched_rt.c +++ b/kernel/sched_rt.c @@ -5,22 +5,14 @@ #ifdef CONFIG_SMP -/* - * The "RT overload" flag: it gets set if a CPU has more than - * one runnable RT task. - */ -static cpumask_t rt_overload_mask; -static atomic_t rto_count; - -static inline int rt_overloaded(void) +static inline int rt_overloaded(struct rq *rq) { - return atomic_read(&rto_count); + return atomic_read(&rq->rd->rto_count); } static inline void rt_set_overload(struct rq *rq) { - rq->rt.overloaded = 1; - cpu_set(rq->cpu, rt_overload_mask); + cpu_set(rq->cpu, rq->rd->rto_mask); /* * Make sure the mask is visible before we set * the overload count. That is checked to determine @@ -29,23 +21,25 @@ static inline void rt_set_overload(struct rq *rq) * updated yet. */ wmb(); - atomic_inc(&rto_count); + atomic_inc(&rq->rd->rto_count); } static inline void rt_clear_overload(struct rq *rq) { /* the order here really doesn't matter */ - atomic_dec(&rto_count); - cpu_clear(rq->cpu, rt_overload_mask); - rq->rt.overloaded = 0; + atomic_dec(&rq->rd->rto_count); + cpu_clear(rq->cpu, rq->rd->rto_mask); } static void update_rt_migration(struct rq *rq) { - if (rq->rt.rt_nr_migratory && (rq->rt.rt_nr_running > 1)) + if (rq->rt.rt_nr_migratory && (rq->rt.rt_nr_running > 1)) { rt_set_overload(rq); - else + rq->rt.overloaded = 1; + } else { rt_clear_overload(rq); + rq->rt.overloaded = 0; + } } #endif /* CONFIG_SMP */ @@ -306,7 +300,7 @@ static int find_lowest_cpus(struct task_struct *task, cpumask_t *lowest_mask) int count = 0; int cpu; - cpus_and(*lowest_mask, cpu_online_map, task->cpus_allowed); + cpus_and(*lowest_mask, task_rq(task)->rd->online, task->cpus_allowed); /* * Scan each rq for the lowest prio. @@ -580,18 +574,12 @@ static int pull_rt_task(struct rq *this_rq) struct task_struct *p, *next; struct rq *src_rq; - /* - * If cpusets are used, and we have overlapping - * run queue cpusets, then this algorithm may not catch all. - * This is just the price you pay on trying to keep - * dirtying caches down on large SMP machines. - */ - if (likely(!rt_overloaded())) + if (likely(!rt_overloaded(this_rq))) return 0; next = pick_next_task_rt(this_rq); - for_each_cpu_mask(cpu, rt_overload_mask) { + for_each_cpu_mask(cpu, this_rq->rd->rto_mask) { if (this_cpu == cpu) continue; @@ -811,6 +799,20 @@ static void task_tick_rt(struct rq *rq, struct task_struct *p) } } +/* Assumes rq->lock is held */ +static void join_domain_rt(struct rq *rq) +{ + if (rq->rt.overloaded) + rt_set_overload(rq); +} + +/* Assumes rq->lock is held */ +static void leave_domain_rt(struct rq *rq) +{ + if (rq->rt.overloaded) + rt_clear_overload(rq); +} + static void set_curr_task_rt(struct rq *rq) { struct task_struct *p = rq->curr; @@ -840,4 +842,7 @@ const struct sched_class rt_sched_class = { .set_curr_task = set_curr_task_rt, .task_tick = task_tick_rt, + + .join_domain = join_domain_rt, + .leave_domain = leave_domain_rt, }; |