1 files changed, 17 insertions, 9 deletions

diff --git a/include/linux/printk.h b/include/linux/printk.h
index 694925837a16..fa47e2708c01 100644
--- a/include/linux/printk.h
+++ b/include/linux/printk.h
@@ -5,6 +5,7 @@
 #include <linux/init.h>
 #include <linux/kern_levels.h>
 #include <linux/linkage.h>
+#include <linux/cache.h>
 
 extern const char linux_banner[];
 extern const char linux_proc_banner[];
@@ -88,6 +89,13 @@ struct va_format {
 #define HW_ERR          "[Hardware Error]: "
 
 /*
+ * DEPRECATED
+ * Add this to a message whenever you want to warn user space about the use
+ * of a deprecated aspect of an API so they can stop using it
+ */
+#define DEPRECATED      "[Deprecated]: "
+
+/*
  * Dummy printk for disabled debugging statements to use whilst maintaining
  * gcc's format and side-effect checking.
  */
@@ -253,17 +261,17 @@ extern asmlinkage void dump_stack(void) __cold;
  */
 
 #ifdef CONFIG_PRINTK
-#define printk_once(fmt, ...)                   \
-({                                              \
-        static bool __print_once;               \
-                                                \
-        if (!__print_once) {                    \
-                __print_once = true;            \
-                printk(fmt, ##__VA_ARGS__);     \
-        }                                       \
+#define printk_once(fmt, ...)                                   \
+({                                                              \
+        static bool __print_once __read_mostly;                 \
+                                                                \
+        if (!__print_once) {                                    \
+                __print_once = true;                            \
+                printk(fmt, ##__VA_ARGS__);                     \
+        }                                                       \
 })
 #else
-#define printk_once(fmt, ...)                   \
+#define printk_once(fmt, ...)                                   \
         no_printk(fmt, ##__VA_ARGS__)
 #endif