openwrt/target/linux/generic-2.6/patches-2.6.21/32-time_fix_timespec_add_ns...

18 lines
480 B
Diff
Raw Normal View History

time: prevent the loop in timespec_add_ns() from being optimised away
Since some architectures don't support __udivdi3().
--- a/include/linux/time.h
+++ b/include/linux/time.h
@@ -170,6 +170,10 @@ static inline void timespec_add_ns(struc
{
ns += a->tv_nsec;
while(unlikely(ns >= NSEC_PER_SEC)) {
+ /* The following asm() prevents the compiler from
+ * optimising this loop into a modulo operation. */
+ asm("" : "+r"(ns));
+
ns -= NSEC_PER_SEC;
a->tv_sec++;
}