From 9fdd3bc9005824704f9802bec7b3e06f5edae434 Mon Sep 17 00:00:00 2001 From: "Paul E. McKenney" Date: Tue, 29 Jul 2014 14:50:47 -0700 Subject: rcu: Break more call_rcu() deadlock involving scheduler and perf Commit 96d3fd0d315a9 (rcu: Break call_rcu() deadlock involving scheduler and perf) covered the case where __call_rcu_nocb_enqueue() needs to wake the rcuo kthread due to the queue being initially empty, but did not do anything for the case where the queue was overflowing. This commit therefore also defers wakeup for the overflow case. Signed-off-by: Paul E. McKenney --- include/trace/events/rcu.h | 3 +++ 1 file changed, 3 insertions(+) (limited to 'include/trace') diff --git a/include/trace/events/rcu.h b/include/trace/events/rcu.h index aca382266411..9b56f37148cf 100644 --- a/include/trace/events/rcu.h +++ b/include/trace/events/rcu.h @@ -180,9 +180,12 @@ TRACE_EVENT(rcu_grace_period_init, * argument is a string as follows: * * "WakeEmpty": Wake rcuo kthread, first CB to empty list. + * "WakeEmptyIsDeferred": Wake rcuo kthread later, first CB to empty list. * "WakeOvf": Wake rcuo kthread, CB list is huge. + * "WakeOvfIsDeferred": Wake rcuo kthread later, CB list is huge. * "WakeNot": Don't wake rcuo kthread. * "WakeNotPoll": Don't wake rcuo kthread because it is polling. + * "DeferredWake": Carried out the "IsDeferred" wakeup. * "Poll": Start of new polling cycle for rcu_nocb_poll. * "Sleep": Sleep waiting for CBs for !rcu_nocb_poll. * "WokeEmpty": rcuo kthread woke to find empty list. -- cgit v1.2.3