Update Linux to v5.4.2

Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/include/linux/delayacct.h b/include/linux/delayacct.h
index 31c865d..2d3bdcc 100644
--- a/include/linux/delayacct.h
+++ b/include/linux/delayacct.h
@@ -1,17 +1,7 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
 /* delayacct.h - per-task delay accounting
  *
  * Copyright (C) Shailabh Nagar, IBM Corp. 2006
- *
- * This program is free software;  you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY;  without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See
- * the GNU General Public License for more details.
- *
  */
 
 #ifndef _LINUX_DELAYACCT_H
@@ -57,7 +47,12 @@
 
 	u64 freepages_start;
 	u64 freepages_delay;	/* wait for memory reclaim */
+
+	u64 thrashing_start;
+	u64 thrashing_delay;	/* wait for thrashing page */
+
 	u32 freepages_count;	/* total count of memory reclaim */
+	u32 thrashing_count;	/* total count of thrash waits */
 };
 #endif
 
@@ -76,6 +71,8 @@
 extern __u64 __delayacct_blkio_ticks(struct task_struct *);
 extern void __delayacct_freepages_start(void);
 extern void __delayacct_freepages_end(void);
+extern void __delayacct_thrashing_start(void);
+extern void __delayacct_thrashing_end(void);
 
 static inline int delayacct_is_task_waiting_on_io(struct task_struct *p)
 {
@@ -156,6 +153,18 @@
 		__delayacct_freepages_end();
 }
 
+static inline void delayacct_thrashing_start(void)
+{
+	if (current->delays)
+		__delayacct_thrashing_start();
+}
+
+static inline void delayacct_thrashing_end(void)
+{
+	if (current->delays)
+		__delayacct_thrashing_end();
+}
+
 #else
 static inline void delayacct_set_flag(int flag)
 {}
@@ -182,6 +191,10 @@
 {}
 static inline void delayacct_freepages_end(void)
 {}
+static inline void delayacct_thrashing_start(void)
+{}
+static inline void delayacct_thrashing_end(void)
+{}
 
 #endif /* CONFIG_TASK_DELAY_ACCT */