diff options
| -rw-r--r-- | drivers/cpuidle/governors/menu.c | 32 |
1 files changed, 22 insertions, 10 deletions
diff --git a/drivers/cpuidle/governors/menu.c b/drivers/cpuidle/governors/menu.c index 680ff20e5528..48ebbde750e5 100644 --- a/drivers/cpuidle/governors/menu.c +++ b/drivers/cpuidle/governors/menu.c @@ -116,30 +116,37 @@ static void menu_update(struct cpuidle_driver *drv, struct cpuidle_device *dev); */ static unsigned int get_typical_interval(struct menu_device *data) { - unsigned int max, divisor, thresh = UINT_MAX; + s64 value, min_thresh = -1, max_thresh = UINT_MAX; + unsigned int max, min, divisor; u64 avg, variance, avg_sq; int i; again: /* Compute the average and variance of past intervals. */ max = 0; + min = UINT_MAX; avg = 0; variance = 0; divisor = 0; for (i = 0; i < INTERVALS; i++) { - unsigned int value = data->intervals[i]; - - /* Discard data points above or at the threshold. */ - if (value >= thresh) + value = data->intervals[i]; + /* + * Discard the samples outside the interval between the min and + * max thresholds. + */ + if (value <= min_thresh || value >= max_thresh) continue; divisor++; avg += value; - variance += (u64)value * value; + variance += value * value; if (value > max) max = value; + + if (value < min) + min = value; } if (!max) @@ -175,10 +182,10 @@ again: } /* - * If we have outliers to the upside in our distribution, discard - * those by setting the threshold to exclude these outliers, then + * If there are outliers, discard them by setting thresholds to exclude + * data points at a large enough distance from the average, then * calculate the average and standard deviation again. Once we get - * down to the bottom 3/4 of our samples, stop excluding samples. + * down to the last 3/4 of our samples, stop excluding samples. * * This can deal with workloads that have long pauses interspersed * with sporadic activity with a bunch of short pauses. @@ -186,7 +193,12 @@ again: if ((divisor * 4) <= INTERVALS * 3) return UINT_MAX; - thresh = max; + /* Update the thresholds for the next round. */ + if (avg - min > max - avg) + min_thresh = min; + else + max_thresh = max; + goto again; } |