[PATCH 4/8] sched,rcu,tracing: Mark preempt_count_{add,sub}() notrace

From: Peter Zijlstra
Date: Wed Feb 12 2020 - 04:44:13 EST


Because of the requirement that no tracing happens until after we've
incremented preempt_count, see nmi_enter() / trace_rcu_enter(), mark
these functions as notrace.

Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
---
kernel/sched/core.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -3781,7 +3781,7 @@ static inline void preempt_latency_start
}
}

-void preempt_count_add(int val)
+void notrace preempt_count_add(int val)
{
#ifdef CONFIG_DEBUG_PREEMPT
/*
@@ -3813,7 +3813,7 @@ static inline void preempt_latency_stop(
trace_preempt_on(CALLER_ADDR0, get_lock_parent_ip());
}

-void preempt_count_sub(int val)
+void notrace preempt_count_sub(int val)
{
#ifdef CONFIG_DEBUG_PREEMPT
/*