time: Add the common weak version of update_persistent_clock()

The weak update_persistent_clock64() calls update_persistent_clock(),
if the architecture defines an update_persistent_clock64() to replace
and remove its update_persistent_clock() version, when building the
kernel the linker will throw an undefined symbol error, that is, any
arch that switches to update_persistent_clock64() will have this issue.

To solve the issue, we add the common weak update_persistent_clock().

Cc: Prarit Bhargava <[email protected]>
Cc: Richard Cochran <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: Arnd Bergmann <[email protected]>
Signed-off-by: Xunlei Pang <[email protected]>
Signed-off-by: John Stultz <[email protected]>

1 files changed, 5 insertions, 0 deletions

diff --git a/kernel/time/ntp.c b/kernel/time/ntp.c
index fb4d98c7fd43..df68cb875248 100644
--- a/kernel/time/ntp.c
+++ b/kernel/time/ntp.c
@@ -487,6 +487,11 @@ out:
 }
 
 #ifdef CONFIG_GENERIC_CMOS_UPDATE
+int __weak update_persistent_clock(struct timespec now)
+{
+	return -ENODEV;
+}
+
 int __weak update_persistent_clock64(struct timespec64 now64)
 {
 	struct timespec now;