diff --git a/kernel/sched/rt.c b/kernel/sched/rt.c index 6f42703edc47..298f62b8662d 100644 --- a/kernel/sched/rt.c +++ b/kernel/sched/rt.c @@ -1990,8 +1990,11 @@ static void tell_cpu_to_push(struct rq *rq) rto_start_unlock(&rq->rd->rto_loop_start); - if (cpu >= 0) + if (cpu >= 0) { + /* Make sure the rd does not get freed while pushing */ + sched_get_rd(rq->rd); irq_work_queue_on(&rq->rd->rto_push_work, cpu); + } } /* Called from hardirq context */ @@ -2021,8 +2024,10 @@ void rto_push_irq_work_func(struct irq_work *work) raw_spin_unlock(&rd->rto_lock); - if (cpu < 0) + if (cpu < 0) { + sched_put_rd(rd); return; + } /* Try the next RT overloaded CPU */ irq_work_queue_on(&rd->rto_push_work, cpu); diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h index b732e779fe7d..307c35d33660 100644 --- a/kernel/sched/sched.h +++ b/kernel/sched/sched.h @@ -661,6 +661,8 @@ extern struct mutex sched_domains_mutex; extern void init_defrootdomain(void); extern int sched_init_domains(const struct cpumask *cpu_map); extern void rq_attach_root(struct rq *rq, struct root_domain *rd); +extern void sched_get_rd(struct root_domain *rd); +extern void sched_put_rd(struct root_domain *rd); #ifdef HAVE_RT_PUSH_IPI extern void rto_push_irq_work_func(struct irq_work *work); diff --git a/kernel/sched/topology.c b/kernel/sched/topology.c index 093f2ceba2e2..659e075ef70b 100644 --- a/kernel/sched/topology.c +++ b/kernel/sched/topology.c @@ -258,6 +258,19 @@ void rq_attach_root(struct rq *rq, struct root_domain *rd) call_rcu_sched(&old_rd->rcu, free_rootdomain); } +void sched_get_rd(struct root_domain *rd) +{ + atomic_inc(&rd->refcount); +} + +void sched_put_rd(struct root_domain *rd) +{ + if (!atomic_dec_and_test(&rd->refcount)) + return; + + call_rcu_sched(&rd->rcu, free_rootdomain); +} + static int init_rootdomain(struct root_domain *rd) { if (!zalloc_cpumask_var(&rd->span, GFP_KERNEL))