[PATCH v16 42/42] dept: call dept_hardirqs_off() in local_irq_*() regardless of irq state

[Byungchul Park]

For dept to function properly, dept_task()->hardirqs_enabled must be set
correctly.  If it fails to set this value to false, for example, dept
may mistakenly think irq is still enabled even when it's not.

Do dept_hardirqs_off() regardless of irq state not to miss any
unexpected cases by any chance e.g. changes of the state by asm code.

Signed-off-by: Byungchul Park <byungchul at sk.com>
---
 include/linux/irqflags.h | 14 ++++++++++++++
 kernel/dependency/dept.c |  1 +
 2 files changed, 15 insertions(+)

diff --git a/include/linux/irqflags.h b/include/linux/irqflags.h
index d8b9cf093f83..586f5bad4da7 100644
--- a/include/linux/irqflags.h
+++ b/include/linux/irqflags.h
@@ -214,6 +214,13 @@ extern void warn_bogus_irq_restore(void);
 		raw_local_irq_disable();		\
 		if (!was_disabled)			\
 			trace_hardirqs_off();		\
+		/*					\
+		 * Just in case that C code has missed	\
+		 * trace_hardirqs_off() at the first	\
+		 * place e.g. disabling irq at asm code.\
+		 */					\
+		else					\
+			dept_hardirqs_off();		\
 	} while (0)
 
 #define local_irq_save(flags)				\
@@ -221,6 +228,13 @@ extern void warn_bogus_irq_restore(void);
 		raw_local_irq_save(flags);		\
 		if (!raw_irqs_disabled_flags(flags))	\
 			trace_hardirqs_off();		\
+		/*					\
+		 * Just in case that C code has missed	\
+		 * trace_hardirqs_off() at the first	\
+		 * place e.g. disabling irq at asm code.\
+		 */					\
+		else					\
+			dept_hardirqs_off();		\
 	} while (0)
 
 #define local_irq_restore(flags)			\
diff --git a/kernel/dependency/dept.c b/kernel/dependency/dept.c
index a08d0e16978b..4ca1cc04293c 100644
--- a/kernel/dependency/dept.c
+++ b/kernel/dependency/dept.c
@@ -2248,6 +2248,7 @@ void noinstr dept_hardirqs_off(void)
 	 */
 	dept_task()->hardirqs_enabled = false;
 }
+EXPORT_SYMBOL_GPL(dept_hardirqs_off);
 
 void noinstr dept_update_cxt(void)
 {
-- 
2.17.1