Return another timespec to store the difference of two input timespecs ? Would that be useful ?+/*
+ * timespec_diff_ns - Return difference of two timestamps in nanoseconds
+ * In the rare case of @end being earlier than @start, return zero
+ */
+static inline nsec_t timespec_diff_ns(struct timespec *start, struct timespec *end)
+{
+ nsec_t ret;
+
+ ret = (nsec_t)(end->tv_sec - start->tv_sec)*NSEC_PER_SEC;
+ ret += (nsec_t)(end->tv_nsec - start->tv_nsec);
+ if (ret < 0)
+ return 0;
+ return ret;
+}
#endif /* __KERNEL__ */
wouldn't it be more useful to have this return a timespec as well, and
then it'd be generically useful (and it also probably should then be
uninlined ;)