printk/cache: mark printk_once test variable __read_mostly

Add #include <linux/cache.h> to define __read_mostly.

Convert cache.h to use uapi/linux/kernel.h instead
of linux/kernel.h to avoid recursive #includes.

Convert the ALIGN macro to __ALIGN_KERNEL.

printk_once only sets the bool variable tested
once so mark it __read_mostly.

Neaten the alignment so it matches the rest of the
pr_<level>_once #defines too.

Signed-off-by: Joe Perches <joe@perches.com>
Reviewed-by: James Hogan <james.hogan@imgtec.com>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

arch/ia64/include/asm/processor.h

@@ -71,6 +71,7 @@
 #include <linux/compiler.h>
 #include <linux/threads.h>
 #include <linux/types.h>
+#include <linux/bitops.h>
 
 #include <asm/fpu.h>
 #include <asm/page.h>

include/linux/cache.h

@@ -1,11 +1,11 @@
 #ifndef __LINUX_CACHE_H
 #define __LINUX_CACHE_H
 
-#include <linux/kernel.h>
+#include <uapi/linux/kernel.h>
 #include <asm/cache.h>
 
 #ifndef L1_CACHE_ALIGN
-#define L1_CACHE_ALIGN(x) ALIGN(x, L1_CACHE_BYTES)
+#define L1_CACHE_ALIGN(x) __ALIGN_KERNEL(x, L1_CACHE_BYTES)
 #endif
 
 #ifndef SMP_CACHE_BYTES

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[];
@@ -253,17 +254,17 @@ 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