Hello, I use PSCHED_GET_TIME(stamp) to measure the delay of some kernel function. function_name( ) { int psched_clock_scale; psched_time_t stamp1, stamp2; psched_tdiff_t delay; PSCHED_GET_TIME(stamp1); PSCHED_GET_TIME(stamp2); delay=PSCHED_TDIFF(stamp2, stamp1); printk(KERN_INFO "[%ld], [%ld], [%ld]\n", stamp1, stamp2, delay); } But the result like this [135967], [0], [135967]. I really don't know why stamp2 is 0, and I can't find out the scale of stamp1/stamp2. (micro-second ?? ) Thanks. Cheers, Steven - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/