diff --git a/include/linux/ktime.h b/include/linux/ktime.h
index ce59832..7c0ad35 100644
--- a/include/linux/ktime.h
+++ b/include/linux/ktime.h
@@ -150,7 +150,19 @@ static inline ktime_t timeval_to_ktime(struct timeval tv)
 /* Set a ktime_t variable to a value in sec/nsec representation: */
 static inline ktime_t ktime_set(const long secs, const unsigned long nsecs)
 {
-	return (ktime_t) { .tv = { .sec = secs, .nsec = nsecs } };
+	ktime_t res = { .tv = { .sec = secs, .nsec = nsecs }};;
+	
+	/*
+	 * performance trick: the (u32) -NSEC gives 0x00000000Fxxxxxxx
+	 * so we subtract NSEC_PER_SEC and add 1 to the upper 32 bit.
+	 *
+	 * it's equivalent to:
+	 *   tv.nsec -= NSEC_PER_SEC
+	 *   tv.sec ++;
+	 */
+	if (nsecs >= NSEC_PER_SEC)
+		res.tv64 += (u32)-NSEC_PER_SEC;
+	return res;
 }
 
 /**