From: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
To: linux-kernel@vger.kernel.org
Cc: mingo@kernel.org, jiangshanlai@gmail.com, dipankar@in.ibm.com,
akpm@linux-foundation.org, mathieu.desnoyers@efficios.com,
josh@joshtriplett.org, tglx@linutronix.de, peterz@infradead.org,
rostedt@goodmis.org, dhowells@redhat.com, edumazet@google.com,
fweisbec@gmail.com, oleg@redhat.com,
"Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Subject: [PATCH tip/core/rcu 11/20] rcu: More clearly identify grace-period kthread stack dump
Date: Mon, 26 Feb 2018 13:53:01 -0800 [thread overview]
Message-ID: <1519681990-31349-11-git-send-email-paulmck@linux.vnet.ibm.com> (raw)
In-Reply-To: <20180226215219.GA27379@linux.vnet.ibm.com>
It is not always obvious that the stack dump from a starved grace-period
kthread isn't instead that of a CPU stalling the current grace period.
This commit therefore adds a pr_err() flagging these dumps.
Reported-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
---
kernel/rcu/tree.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c
index 86fc087c7777..4d7c727020f0 100644
--- a/kernel/rcu/tree.c
+++ b/kernel/rcu/tree.c
@@ -1350,6 +1350,7 @@ static void rcu_check_gp_kthread_starvation(struct rcu_state *rsp)
rsp->gp_kthread ? rsp->gp_kthread->state : ~0,
rsp->gp_kthread ? task_cpu(rsp->gp_kthread) : -1);
if (rsp->gp_kthread) {
+ pr_err("RCU grace-period kthread stack dump:\n");
sched_show_task(rsp->gp_kthread);
wake_up_process(rsp->gp_kthread);
}
--
2.5.2
next prev parent reply other threads:[~2018-02-26 21:52 UTC|newest]
Thread overview: 21+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-02-26 21:52 [PATCH tip/core/rcu 0/20] Miscellaneous fixes Paul E. McKenney
2018-02-26 21:52 ` [PATCH tip/core/rcu 01/20] rcu: Remove unnecessary spinlock in rcu_boot_init_percpu_data() Paul E. McKenney
2018-02-26 21:52 ` [PATCH tip/core/rcu 02/20] sched/isolation: Eliminate NO_HZ_FULL_ALL Paul E. McKenney
2018-02-26 21:52 ` [PATCH tip/core/rcu 03/20] rcu: Fix CPU offload boot message when no CPUs are offloaded Paul E. McKenney
2018-02-26 21:52 ` [PATCH tip/core/rcu 04/20] doc: Fix typo in rcutorture documentation Paul E. McKenney
2018-02-26 21:52 ` [PATCH tip/core/rcu 05/20] doc: Fix typo in rcu_head comments Paul E. McKenney
2018-02-26 21:52 ` [PATCH tip/core/rcu 06/20] rcu: Call touch_nmi_watchdog() while printing stall warnings Paul E. McKenney
2018-02-26 21:52 ` [PATCH tip/core/rcu 07/20] rcu: Remove obsolete boost statistics for debugfs Paul E. McKenney
2018-02-26 21:52 ` [PATCH tip/core/rcu 08/20] rcu: Remove obsolete callback-invocation " Paul E. McKenney
2018-02-26 21:52 ` [PATCH tip/core/rcu 09/20] rcu: Remove obsolete __rcu_pending() " Paul E. McKenney
2018-02-26 21:53 ` [PATCH tip/core/rcu 10/20] rcu: Remove obsolete force-quiescent-state " Paul E. McKenney
2018-02-26 21:53 ` Paul E. McKenney [this message]
2018-02-26 21:53 ` [PATCH tip/core/rcu 12/20] rcu: Consolidate rcu.h #ifdefs Paul E. McKenney
2018-02-26 21:53 ` [PATCH tip/core/rcu 13/20] rcu: Remove redundant nxttail index macro define Paul E. McKenney
2018-02-26 21:53 ` [PATCH tip/core/rcu 14/20] rcu: Use wrapper for lockdep asserts Paul E. McKenney
2018-02-26 21:53 ` [PATCH tip/core/rcu 15/20] rcu: Fix init_rcu_head() comment Paul E. McKenney
2018-02-26 21:53 ` [PATCH tip/core/rcu 16/20] rcu: Fix misprint in srcu_funnel_exp_start Paul E. McKenney
2018-02-26 21:53 ` [PATCH tip/core/rcu 17/20] rcu: Add more tracing of expedited grace periods Paul E. McKenney
2018-02-26 21:53 ` [PATCH tip/core/rcu 18/20] rcu: Trace expedited GP delays due to transitioning CPUs Paul E. McKenney
2018-02-26 21:53 ` [PATCH tip/core/rcu 19/20] rcu: Make expedited RCU CPU selection avoid unnecessary stores Paul E. McKenney
2018-02-26 21:53 ` [PATCH tip/core/rcu 20/20] rcu: Create RCU-specific workqueues with rescuers Paul E. McKenney
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