Subject: lockdep: Make it RT aware
From: Thomas Gleixner <tglx@linutronix.de>
Date: Sun, 17 Jul 2011 18:51:23 +0200
Origin: https://www.kernel.org/pub/linux/kernel/projects/rt/5.2/older/patches-5.2.9-rt3.tar.xz

teach lockdep that we don't really do softirqs on -RT.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
---
 include/linux/irqflags.h |   23 +++++++++++++++--------
 kernel/locking/lockdep.c |    2 ++
 2 files changed, 17 insertions(+), 8 deletions(-)

--- a/include/linux/irqflags.h
+++ b/include/linux/irqflags.h
@@ -43,14 +43,6 @@ do {						\
 do {						\
 	current->hardirq_context--;		\
 } while (0)
-# define lockdep_softirq_enter()		\
-do {						\
-	current->softirq_context++;		\
-} while (0)
-# define lockdep_softirq_exit()			\
-do {						\
-	current->softirq_context--;		\
-} while (0)
 #else
 # define trace_hardirqs_on()		do { } while (0)
 # define trace_hardirqs_off()		do { } while (0)
@@ -63,6 +55,21 @@ do {						\
 # define lockdep_softirq_enter()	do { } while (0)
 # define lockdep_softirq_exit()		do { } while (0)
 #endif
+
+#if defined(CONFIG_TRACE_IRQFLAGS) && !defined(CONFIG_PREEMPT_RT_FULL)
+# define lockdep_softirq_enter()		\
+do {						\
+	current->softirq_context++;		\
+} while (0)
+# define lockdep_softirq_exit()			\
+do {						\
+	current->softirq_context--;		\
+} while (0)
+
+#else
+# define lockdep_softirq_enter()	do { } while (0)
+# define lockdep_softirq_exit()		do { } while (0)
+#endif
 
 #if defined(CONFIG_IRQSOFF_TRACER) || \
 	defined(CONFIG_PREEMPT_TRACER)
--- a/kernel/locking/lockdep.c
+++ b/kernel/locking/lockdep.c
@@ -4244,6 +4244,7 @@ static void check_flags(unsigned long fl
 		}
 	}
 
+#ifndef CONFIG_PREEMPT_RT_FULL
 	/*
 	 * We dont accurately track softirq state in e.g.
 	 * hardirq contexts (such as on 4KSTACKS), so only
@@ -4258,6 +4259,7 @@ static void check_flags(unsigned long fl
 			DEBUG_LOCKS_WARN_ON(!current->softirqs_enabled);
 		}
 	}
+#endif
 
 	if (!debug_locks)
 		print_irqtrace_events(current);