If the rcutree.use_softirq is configured, when RCU Stall event
happened, dump status of all rcuc kthreads who due to starvation
prevented grace period ends on CPUs that not report quiescent
state.
Signed-off-by: Zqiang <qiang1.zhang@xxxxxxxxx>
---
kernel/rcu/tree_stall.h | 8 +++++---
1 file changed, 5 insertions(+), 3 deletions(-)
diff --git a/kernel/rcu/tree_stall.h b/kernel/rcu/tree_stall.h
index d7956c03edbd..e6ecc32cfe23 100644
--- a/kernel/rcu/tree_stall.h
+++ b/kernel/rcu/tree_stall.h
@@ -348,6 +348,7 @@ static int rcu_print_task_stall(struct rcu_node *rnp, unsigned long flags)
}
#endif /* #else #ifdef CONFIG_PREEMPT_RCU */
+static void rcuc_kthread_dump(struct rcu_data *rdp);
/*
* Dump stacks of all tasks running on stalled CPUs. First try using
* NMIs, but fall back to manual remote stack tracing on architectures
@@ -368,6 +369,7 @@ static void rcu_dump_cpu_stacks(void)
pr_err("Offline CPU %d blocking current GP.\n", cpu);
else if (!trigger_single_cpu_backtrace(cpu))
dump_cpu_task(cpu);
+ rcuc_kthread_dump(per_cpu_ptr(&rcu_data, cpu));
}
raw_spin_unlock_irqrestore_rcu_node(rnp, flags);
}
@@ -471,6 +473,9 @@ static void rcuc_kthread_dump(struct rcu_data *rdp)
unsigned long j;
struct task_struct *rcuc;
+ if (use_softirq)
+ return;
+
rcuc = rdp->rcu_cpu_kthread_task;
if (!rcuc)
return;
@@ -659,9 +664,6 @@ static void print_cpu_stall(unsigned long gps)
rcu_check_gp_kthread_expired_fqs_timer();
rcu_check_gp_kthread_starvation();
- if (!use_softirq)
- rcuc_kthread_dump(rdp);
-
rcu_dump_cpu_stacks();
raw_spin_lock_irqsave_rcu_node(rnp, flags);
--
2.25.1
