- WARN_ON_ONCE(!irqs_disabled());
- now = sched_clock();
-
- if (cpu != raw_smp_processor_id()) {
- struct sched_clock_data *my_scd = this_scd();
-
- lock_double_clock(scd, my_scd);
-
- this_clock = __update_sched_clock(my_scd, now);
- remote_clock = scd->clock;
-
- /*
- * Use the opportunity that we have both locks
- * taken to couple the two clocks: we take the
- * larger time as the latest time for both
- * runqueues. (this creates monotonic movement)
- */
- if (likely((s64)(remote_clock - this_clock) < 0)) {
- clock = this_clock;
- scd->clock = clock;
- } else {
- /*
- * Should be rare, but possible:
- */
- clock = remote_clock;
- my_scd->clock = remote_clock;
- }
-
- __raw_spin_unlock(&my_scd->lock);
- } else {
- __raw_spin_lock(&scd->lock);
- clock = __update_sched_clock(scd, now);
- }