[PATCH v2 2/7] vDSO: Make clockmode constants available without CONFIG_GENERIC_GETTIMEOFDAY

[Thomas Weißschuh]

Some code, for example clocksource drivers, may want to use the vDSO
clockmode constants even when CONFIG_GENERIC_GETTIMEOFDAY=n.
But the symbols are completely hidden in that case, making ugly
ifdeffery necessary.

Provide unlinkable dummy definitions. These can be used with
IS_ENABLED(CONFIG_GENERIC_GETTIMEOFDAY).

As not all architectures provide asm/vdso/clocksource.h,
provide an empty stub in asm-generic for it.

Signed-off-by: Thomas Weißschuh <thomas.weissschuh@xxxxxxxxxxxxx>
---
 include/asm-generic/Kbuild             | 1 +
 include/asm-generic/vdso/clocksource.h | 0
 include/vdso/clocksource.h             | 4 +---
 3 files changed, 2 insertions(+), 3 deletions(-)

diff --git a/include/asm-generic/Kbuild b/include/asm-generic/Kbuild
index 15df9dcb42a5..2bc00c67dc54 100644
--- a/include/asm-generic/Kbuild
+++ b/include/asm-generic/Kbuild
@@ -62,6 +62,7 @@ mandatory-y += topology.h
 mandatory-y += trace_clock.h
 mandatory-y += uaccess.h
 mandatory-y += unwind_user.h
+mandatory-y += vdso/clocksource.h
 mandatory-y += vermagic.h
 mandatory-y += vga.h
 mandatory-y += video.h
diff --git a/include/asm-generic/vdso/clocksource.h b/include/asm-generic/vdso/clocksource.h
new file mode 100644
index 000000000000..e69de29bb2d1
diff --git a/include/vdso/clocksource.h b/include/vdso/clocksource.h
index c682e7c60273..bce81c02a7c6 100644
--- a/include/vdso/clocksource.h
+++ b/include/vdso/clocksource.h
@@ -4,13 +4,11 @@
 
 #include <vdso/limits.h>
 
-#ifdef CONFIG_GENERIC_GETTIMEOFDAY
 #include <asm/vdso/clocksource.h>
-#endif /* CONFIG_GENERIC_GETTIMEOFDAY */
 
 enum vdso_clock_mode {
 	VDSO_CLOCKMODE_NONE,
-#ifdef CONFIG_GENERIC_GETTIMEOFDAY
+#ifdef VDSO_ARCH_CLOCKMODES
 	VDSO_ARCH_CLOCKMODES,
 #endif
 	VDSO_CLOCKMODE_MAX,

-- 
2.55.0