Add option to turn off preemption state tracing

Preemption state tracing is only useful when debugging preemption-
and IPI-related races. Since it creates a lot of clutter in the logs,
this patch turns it off unless explicitly requested.

1 files changed, 14 insertions, 0 deletions

diff --git a/litmus/Kconfig b/litmus/Kconfig
index d7fde6f97e14..94b48e199577 100644
--- a/litmus/Kconfig
+++ b/litmus/Kconfig
@@ -199,6 +199,20 @@ config SCHED_DEBUG_TRACE_CALLER
 
          If unsure, say No.
 
+config PREEMPT_STATE_TRACE
+       bool "Trace preemption state machine transitions"
+       depends on SCHED_DEBUG_TRACE
+       default n
+       help
+         With this option enabled, each CPU will log when it transitions
+         states in the preemption state machine. This state machine is
+         used to determine how to react to IPIs (avoid races with in-flight IPIs).
+
+         Warning: this creates a lot of information in the debug trace. Only
+         recommended when you are debugging preemption-related races.
+
+         If unsure, say No.
+
 endmenu
 
 endmenu