diff options
| -rw-r--r-- | drivers/cpuidle/governors/teo.c | 13 |
1 files changed, 12 insertions, 1 deletions
diff --git a/drivers/cpuidle/governors/teo.c b/drivers/cpuidle/governors/teo.c index c232c95ca7fa..8fe5e1b47ef9 100644 --- a/drivers/cpuidle/governors/teo.c +++ b/drivers/cpuidle/governors/teo.c @@ -106,6 +106,12 @@ #include "gov.h" /* + * Idle state exit latency threshold used for deciding whether or not to check + * the time till the closest expected timer event. + */ +#define LATENCY_THRESHOLD_NS (RESIDENCY_THRESHOLD_NS / 2) + +/* * The PULSE value is added to metrics when they grow and the DECAY_SHIFT value * is used for decreasing metrics on a regular basis. */ @@ -432,9 +438,14 @@ static int teo_select(struct cpuidle_driver *drv, struct cpuidle_device *dev, * duration falls into that range in the majority of cases, assume * non-timer wakeups to be dominant and skip updating the sleep length * to reduce latency. + * + * Also, if the latency constraint is sufficiently low, it will force + * shallow idle states regardless of the wakeup type, so the sleep + * length need not be known in that case. */ if ((!idx || drv->states[idx].target_residency_ns < RESIDENCY_THRESHOLD_NS) && - 2 * cpu_data->short_idles >= cpu_data->total) + (2 * cpu_data->short_idles >= cpu_data->total || + latency_req < LATENCY_THRESHOLD_NS)) goto out_tick; duration_ns = tick_nohz_get_sleep_length(&delta_tick); |