[PATCH] timekeeping: avoid adjust kernel time once hwclock kept inUTC time

[Dong Zhu]

If the Hardware Clock kept in local time,kernel will adjust the time
to be UTC time.But if Hardware Clock kept in UTC time,system will make
a dummy settimeofday call first (sys_tz.tz_minuteswest = 0) to make sure
the time is not shifted,so at this point I think maybe it is not necessary
to set the kernel time once the sys_tz.tz_minuteswest is zero.

Signed-off-by: Dong Zhu <bluezhudong@xxxxxxxxx>
---
 kernel/time.c | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/kernel/time.c b/kernel/time.c
index d226c6a..0b592ce 100644
--- a/kernel/time.c
+++ b/kernel/time.c
@@ -134,9 +134,11 @@ static inline void warp_clock(void)
 {
 	struct timespec adjust;
 
-	adjust = current_kernel_time();
-	adjust.tv_sec += sys_tz.tz_minuteswest * 60;
-	do_settimeofday(&adjust);
+	if (sys_tz.tz_minuteswest) {
+		adjust = current_kernel_time();
+		adjust.tv_sec += sys_tz.tz_minuteswest * 60;
+		do_settimeofday(&adjust);
+	}
 }
 
 /*
-- 
1.7.11.7


-- 
Best Regards,
Dong Zhu
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