diff --git a/kernel/sched_debug.c b/kernel/sched_debug.c index 4293cfa9681..16eeba4e416 100644 --- a/kernel/sched_debug.c +++ b/kernel/sched_debug.c @@ -145,6 +145,19 @@ static void print_rq(struct seq_file *m, struct rq *rq, int rq_cpu) read_unlock_irqrestore(&tasklist_lock, flags); } +#if defined(CONFIG_CGROUP_SCHED) && \ + (defined(CONFIG_FAIR_GROUP_SCHED) || defined(CONFIG_RT_GROUP_SCHED)) +static void task_group_path(struct task_group *tg, char *buf, int buflen) +{ + /* may be NULL if the underlying cgroup isn't fully-created yet */ + if (!tg->css.cgroup) { + buf[0] = '\0'; + return; + } + cgroup_path(tg->css.cgroup, buf, buflen); +} +#endif + void print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq) { s64 MIN_vruntime = -1, min_vruntime, max_vruntime = -1, @@ -154,10 +167,10 @@ void print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq) unsigned long flags; #if defined(CONFIG_CGROUP_SCHED) && defined(CONFIG_FAIR_GROUP_SCHED) - char path[128] = ""; + char path[128]; struct task_group *tg = cfs_rq->tg; - cgroup_path(tg->css.cgroup, path, sizeof(path)); + task_group_path(tg, path, sizeof(path)); SEQ_printf(m, "\ncfs_rq[%d]:%s\n", cpu, path); #elif defined(CONFIG_USER_SCHED) && defined(CONFIG_FAIR_GROUP_SCHED) @@ -208,10 +221,10 @@ void print_cfs_rq(struct seq_file *m, int cpu, struct cfs_rq *cfs_rq) void print_rt_rq(struct seq_file *m, int cpu, struct rt_rq *rt_rq) { #if defined(CONFIG_CGROUP_SCHED) && defined(CONFIG_RT_GROUP_SCHED) - char path[128] = ""; + char path[128]; struct task_group *tg = rt_rq->tg; - cgroup_path(tg->css.cgroup, path, sizeof(path)); + task_group_path(tg, path, sizeof(path)); SEQ_printf(m, "\nrt_rq[%d]:%s\n", cpu, path); #else