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-rw-r--r--kernel/sched.c7
-rw-r--r--kernel/sched_rt.c57
2 files changed, 38 insertions, 26 deletions
diff --git a/kernel/sched.c b/kernel/sched.c
index 34b7d72..35ef06c 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 4d0a60e..b049e51 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,
};
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