- while (pl->period != global_period) {
- unsigned long val = percpu_counter_read(&pl->events);
- unsigned long half = (val + 1) >> 1;
-
- /*
- * Half of zero won't be much less, break out.
- * This limits the loop to shift iterations, even
- * if we missed a million.
- */
- if (!val)
- break;
-
- percpu_counter_add(&pl->events, -half);
- pl->period += period;
- }
+ period = (global_period - pl->period) >> (pg->shift - 1);
+ if (period < BITS_PER_LONG) {
+ s64 val = percpu_counter_read(&pl->events);
+
+ if (val < (nr_cpu_ids * PROP_BATCH))
+ val = percpu_counter_sum(&pl->events);
+
+ __percpu_counter_add(&pl->events, -val + (val >> period),
+ PROP_BATCH);
+ } else
+ percpu_counter_set(&pl->events, 0);
+