sched/core: Use dl_bw_of() under rcu_read_lock_sched()

As per commit f10e00f4bf36 ("sched/dl: Use dl_bw_of() under
rcu_read_lock_sched()"), dl_bw_of() has to be protected by
rcu_read_lock_sched().

Signed-off-by: Juri Lelli <juri.lelli@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/1414497286-28824-1-git-send-email-juri.lelli@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>

diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 379cb87da69df36798a38bb66551a97acf091dbb..df0569ebec0f7f1b35e28402e834beb6064c7873 100644 (file)
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -4661,6 +4661,7 @@ int cpuset_cpumask_can_shrink(const struct cpumask *cur,
        struct dl_bw *cur_dl_b;
        unsigned long flags;
 
+       rcu_read_lock_sched();
        cur_dl_b = dl_bw_of(cpumask_any(cur));
        trial_cpus = cpumask_weight(trial);
 
@@ -4669,6 +4670,7 @@ int cpuset_cpumask_can_shrink(const struct cpumask *cur,
            cur_dl_b->bw * trial_cpus < cur_dl_b->total_bw)
                ret = 0;
        raw_spin_unlock_irqrestore(&cur_dl_b->lock, flags);
+       rcu_read_unlock_sched();
 
        return ret;
 }
@@ -4697,11 +4699,13 @@ int task_can_attach(struct task_struct *p,
                                              cs_cpus_allowed)) {
                unsigned int dest_cpu = cpumask_any_and(cpu_active_mask,
                                                        cs_cpus_allowed);
-               struct dl_bw *dl_b = dl_bw_of(dest_cpu);
+               struct dl_bw *dl_b;
                bool overflow;
                int cpus;
                unsigned long flags;
 
+               rcu_read_lock_sched();
+               dl_b = dl_bw_of(dest_cpu);
                raw_spin_lock_irqsave(&dl_b->lock, flags);
                cpus = dl_bw_cpus(dest_cpu);
                overflow = __dl_overflow(dl_b, cpus, 0, p->dl.dl_bw);
@@ -4717,6 +4721,7 @@ int task_can_attach(struct task_struct *p,
                        __dl_add(dl_b, p->dl.dl_bw);
                }
                raw_spin_unlock_irqrestore(&dl_b->lock, flags);
+               rcu_read_unlock_sched();
 
        }
 #endif