[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Date: Sun, 11 Nov 2018 12:20:20 -0800
From: "Paul E. McKenney" <paulmck@...ux.ibm.com>
To: linux-kernel@...r.kernel.org
Cc: mingo@...nel.org, jiangshanlai@...il.com, dipankar@...ibm.com,
akpm@...ux-foundation.org, mathieu.desnoyers@...icios.com,
josh@...htriplett.org, tglx@...utronix.de, peterz@...radead.org,
rostedt@...dmis.org, dhowells@...hat.com, edumazet@...gle.com,
fweisbec@...il.com, oleg@...hat.com, joel@...lfernandes.org,
"Paul E. McKenney" <paulmck@...ux.ibm.com>
Subject: [PATCH tip/core/rcu 10/17] rcu: Print per-CPU callback counts for forward-progress failures
This commit prints out the non-zero per-CPU callback counts when a
forware-progress error (OOM event) occurs.
Signed-off-by: Paul E. McKenney <paulmck@...ux.ibm.com>
[ paulmck: Fix a pair of uninitialized locals spotted by kbuild test robot. ]
---
kernel/rcu/tree.c | 18 ++++++++++++++++++
1 file changed, 18 insertions(+)
diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c
index 67f2c7a055b6..cef7d9867508 100644
--- a/kernel/rcu/tree.c
+++ b/kernel/rcu/tree.c
@@ -2672,6 +2672,10 @@ rcu_check_gp_start_stall(struct rcu_node *rnp, struct rcu_data *rdp)
*/
void rcu_fwd_progress_check(unsigned long j)
{
+ unsigned long cbs;
+ int cpu;
+ unsigned long max_cbs = 0;
+ int max_cpu = -1;
struct rcu_data *rdp;
if (rcu_gp_in_progress()) {
@@ -2682,6 +2686,20 @@ void rcu_fwd_progress_check(unsigned long j)
rcu_check_gp_start_stall(rdp->mynode, rdp, j);
preempt_enable();
}
+ for_each_possible_cpu(cpu) {
+ cbs = rcu_get_n_cbs_cpu(cpu);
+ if (!cbs)
+ continue;
+ if (max_cpu < 0)
+ pr_info("%s: callbacks", __func__);
+ pr_cont(" %d: %lu", cpu, cbs);
+ if (cbs <= max_cbs)
+ continue;
+ max_cbs = cbs;
+ max_cpu = cpu;
+ }
+ if (max_cpu >= 0)
+ pr_cont("\n");
}
EXPORT_SYMBOL_GPL(rcu_fwd_progress_check);
--
2.17.1
Powered by blists - more mailing lists