jump_label: Allow jump labels to be used in assembly

To use jump labels in assembly we need the HAVE_JUMP_LABEL
define, so we select a fallback version if the toolchain does
not support them.

Modify linux/jump_label.h so it can be included by assembly
files. We also need to add -DCC_HAVE_ASM_GOTO to KBUILD_AFLAGS.

Signed-off-by: Anton Blanchard <[email protected]>
Acked-by: Peter Zijlstra (Intel) <[email protected]>
Cc: Andrew Morton <[email protected]>
Cc: Linus Torvalds <[email protected]>
Cc: Paul E. McKenney <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>

diff --git a/Makefile b/Makefile
index 9fab639727c78e5370538afcd6980f167af6fdf6..a2aa475543e9c17f59a228daa76fe5caae88d47a 100644 (file)
--- a/Makefile
+++ b/Makefile
@@ -779,6 +779,7 @@ KBUILD_ARFLAGS := $(call ar-option,D)
 # check for 'asm goto'
 ifeq ($(shell $(CONFIG_SHELL) $(srctree)/scripts/gcc-goto.sh $(CC)), y)
        KBUILD_CFLAGS += -DCC_HAVE_ASM_GOTO
+       KBUILD_AFLAGS += -DCC_HAVE_ASM_GOTO
 endif
 
 include $(srctree)/scripts/Makefile.kasan

diff --git a/include/linux/jump_label.h b/include/linux/jump_label.h
index 98f923b6a0eaa78ee8b4ffdf57c87f146e3c03d6..f4de473f226b8ab5332dabc7083b74c80de8a664 100644 (file)
--- a/include/linux/jump_label.h
+++ b/include/linux/jump_label.h
@@ -45,6 +45,12 @@
  * same as using STATIC_KEY_INIT_FALSE.
  */
 
+#if defined(CC_HAVE_ASM_GOTO) && defined(CONFIG_JUMP_LABEL)
+# define HAVE_JUMP_LABEL
+#endif
+
+#ifndef __ASSEMBLY__
+
 #include <linux/types.h>
 #include <linux/compiler.h>
 #include <linux/bug.h>
@@ -55,7 +61,7 @@ extern bool static_key_initialized;
                                    "%s used before call to jump_label_init", \
                                    __func__)
 
-#if defined(CC_HAVE_ASM_GOTO) && defined(CONFIG_JUMP_LABEL)
+#ifdef HAVE_JUMP_LABEL
 
 struct static_key {
        atomic_t enabled;
@@ -66,13 +72,18 @@ struct static_key {
 #endif
 };
 
-# include <asm/jump_label.h>
-# define HAVE_JUMP_LABEL
 #else
 struct static_key {
        atomic_t enabled;
 };
-#endif /* CC_HAVE_ASM_GOTO && CONFIG_JUMP_LABEL */
+#endif /* HAVE_JUMP_LABEL */
+#endif /* __ASSEMBLY__ */
+
+#ifdef HAVE_JUMP_LABEL
+#include <asm/jump_label.h>
+#endif
+
+#ifndef __ASSEMBLY__
 
 enum jump_label_type {
        JUMP_LABEL_DISABLE = 0,
@@ -203,3 +214,5 @@ static inline bool static_key_enabled(struct static_key *key)
 }
 
 #endif /* _LINUX_JUMP_LABEL_H */
+
+#endif /* __ASSEMBLY__ */