[PATCH v15 35/43] dept: make dept stop from working on debug_locks_off()

[Byungchul Park]

For many reasons, debug_locks_off() is called to stop lock debuging
feature e.g. on panic().  dept should also stop it in the conditions.

Signed-off-by: Byungchul Park <byungchul at sk.com>
---
 include/linux/dept.h     | 2 ++
 kernel/dependency/dept.c | 6 ++++++
 lib/debug_locks.c        | 2 ++
 3 files changed, 10 insertions(+)

diff --git a/include/linux/dept.h b/include/linux/dept.h
index 19d72b0b0c4b..a6ff9db9bcf9 100644
--- a/include/linux/dept.h
+++ b/include/linux/dept.h
@@ -395,6 +395,7 @@ struct dept_ext_wgen {
 	unsigned int wgen;
 };
 
+extern void dept_stop_emerg(void);
 extern void dept_on(void);
 extern void dept_off(void);
 extern void dept_init(void);
@@ -447,6 +448,7 @@ struct dept_ext_wgen { };
 
 #define DEPT_MAP_INITIALIZER(n, k) { }
 
+#define dept_stop_emerg()				do { } while (0)
 #define dept_on()					do { } while (0)
 #define dept_off()					do { } while (0)
 #define dept_init()					do { } while (0)
diff --git a/kernel/dependency/dept.c b/kernel/dependency/dept.c
index 5397167c7031..3313ac4df3a6 100644
--- a/kernel/dependency/dept.c
+++ b/kernel/dependency/dept.c
@@ -186,6 +186,12 @@ static void dept_unlock(void)
 	arch_spin_unlock(&dept_spin);
 }
 
+void dept_stop_emerg(void)
+{
+	WRITE_ONCE(dept_stop, 1);
+}
+EXPORT_SYMBOL_GPL(dept_stop_emerg);
+
 enum bfs_ret {
 	BFS_CONTINUE,
 	BFS_DONE,
diff --git a/lib/debug_locks.c b/lib/debug_locks.c
index a75ee30b77cb..14a965914a8f 100644
--- a/lib/debug_locks.c
+++ b/lib/debug_locks.c
@@ -38,6 +38,8 @@ EXPORT_SYMBOL_GPL(debug_locks_silent);
  */
 int debug_locks_off(void)
 {
+	dept_stop_emerg();
+
 	if (debug_locks && __debug_locks_off()) {
 		if (!debug_locks_silent) {
 			console_verbose();
-- 
2.17.1