From bd2b879a1ca55486fdb9dcac691bfd3dd79c83d6 Mon Sep 17 00:00:00 2001 From: "Paul E. McKenney" Date: Wed, 4 Oct 2017 12:29:01 -0700 Subject: rcu: Add tracing to irq/NMI dyntick-idle transitions Signed-off-by: Paul E. McKenney --- kernel/rcu/tree.c | 6 ++++++ 1 file changed, 6 insertions(+) (limited to 'kernel/rcu') diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c index 444aa2b..d069ba2 100644 --- a/kernel/rcu/tree.c +++ b/kernel/rcu/tree.c @@ -880,12 +880,15 @@ void rcu_nmi_exit(void) * leave it in non-RCU-idle state. */ if (rdtp->dynticks_nmi_nesting != 1) { + trace_rcu_dyntick(TPS("--="), rdtp->dynticks_nmi_nesting, + rdtp->dynticks_nmi_nesting - 2); WRITE_ONCE(rdtp->dynticks_nmi_nesting, /* No store tearing. */ rdtp->dynticks_nmi_nesting - 2); return; } /* This NMI interrupted an RCU-idle CPU, restore RCU-idleness. */ + trace_rcu_dyntick(TPS("Startirq"), rdtp->dynticks_nmi_nesting, 0); WRITE_ONCE(rdtp->dynticks_nmi_nesting, 0); /* Avoid store tearing. */ rcu_dynticks_eqs_enter(); } @@ -1057,6 +1060,9 @@ void rcu_nmi_enter(void) rcu_dynticks_eqs_exit(); incby = 1; } + trace_rcu_dyntick(incby == 1 ? TPS("Endirq") : TPS("++="), + rdtp->dynticks_nmi_nesting, + rdtp->dynticks_nmi_nesting + incby); WRITE_ONCE(rdtp->dynticks_nmi_nesting, /* Prevent store tearing. */ rdtp->dynticks_nmi_nesting + incby); barrier(); -- cgit v1.1