summaryrefslogtreecommitdiff
path: root/kernel/rcu/tree_stall.h
diff options
context:
space:
mode:
Diffstat (limited to 'kernel/rcu/tree_stall.h')
-rw-r--r--kernel/rcu/tree_stall.h35
1 files changed, 35 insertions, 0 deletions
diff --git a/kernel/rcu/tree_stall.h b/kernel/rcu/tree_stall.h
index 21bebf7c9030..0c5d8516516a 100644
--- a/kernel/rcu/tree_stall.h
+++ b/kernel/rcu/tree_stall.h
@@ -379,6 +379,15 @@ static bool rcu_is_gp_kthread_starving(unsigned long *jp)
return j > 2 * HZ;
}
+static bool rcu_is_rcuc_kthread_starving(struct rcu_data *rdp, unsigned long *jp)
+{
+ unsigned long j = jiffies - READ_ONCE(rdp->rcuc_activity);
+
+ if (jp)
+ *jp = j;
+ return j > 2 * HZ;
+}
+
/*
* Print out diagnostic information for the specified stalled CPU.
*
@@ -430,6 +439,29 @@ static void print_cpu_stall_info(int cpu)
falsepositive ? " (false positive?)" : "");
}
+static void rcuc_kthread_dump(struct rcu_data *rdp)
+{
+ int cpu;
+ unsigned long j;
+ struct task_struct *rcuc;
+
+ rcuc = rdp->rcu_cpu_kthread_task;
+ if (!rcuc)
+ return;
+
+ cpu = task_cpu(rcuc);
+ if (cpu_is_offline(cpu) || idle_cpu(cpu))
+ return;
+
+ if (!rcu_is_rcuc_kthread_starving(rdp, &j))
+ return;
+
+ pr_err("%s kthread starved for %ld jiffies\n", rcuc->comm, j);
+ sched_show_task(rcuc);
+ if (!trigger_single_cpu_backtrace(cpu))
+ dump_cpu_task(cpu);
+}
+
/* Complain about starvation of grace-period kthread. */
static void rcu_check_gp_kthread_starvation(void)
{
@@ -601,6 +633,9 @@ 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);