diff options
author | Segher Boessenkool <segher@kernel.crashing.org> | 2008-03-04 17:59:54 -0500 |
---|---|---|
committer | Thomas Gleixner <tglx@linutronix.de> | 2008-03-09 03:42:57 -0400 |
commit | 38332cb98772f5ea757e6486bed7ed0381cb5f98 (patch) | |
tree | 5690b915ed9e9a64e67520df70329081900dca85 | |
parent | e48af19f56eb47a1f908ee8f16df9d246f955b21 (diff) |
time: prevent the loop in timespec_add_ns() from being optimised away
Since some architectures don't support __udivdi3().
Signed-off-by: Segher Boessenkool <segher@kernel.crashing.org>
Cc: john stultz <johnstul@us.ibm.com>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
-rw-r--r-- | include/linux/time.h | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/include/linux/time.h b/include/linux/time.h index 2091a19f1655..d32ef0ad4c0a 100644 --- a/include/linux/time.h +++ b/include/linux/time.h | |||
@@ -174,6 +174,10 @@ static inline void timespec_add_ns(struct timespec *a, u64 ns) | |||
174 | { | 174 | { |
175 | ns += a->tv_nsec; | 175 | ns += a->tv_nsec; |
176 | while(unlikely(ns >= NSEC_PER_SEC)) { | 176 | while(unlikely(ns >= NSEC_PER_SEC)) { |
177 | /* The following asm() prevents the compiler from | ||
178 | * optimising this loop into a modulo operation. */ | ||
179 | asm("" : "+r"(ns)); | ||
180 | |||
177 | ns -= NSEC_PER_SEC; | 181 | ns -= NSEC_PER_SEC; |
178 | a->tv_sec++; | 182 | a->tv_sec++; |
179 | } | 183 | } |