summaryrefslogtreecommitdiff
path: root/drivers/cpuidle
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/cpuidle')
-rw-r--r--drivers/cpuidle/Kconfig2
-rw-r--r--drivers/cpuidle/cpuidle.c6
-rw-r--r--drivers/cpuidle/governors/ladder.c9
-rw-r--r--drivers/cpuidle/governors/menu.c23
4 files changed, 25 insertions, 15 deletions
diff --git a/drivers/cpuidle/Kconfig b/drivers/cpuidle/Kconfig
index 8c7930b5a65f..7e48eb5bf0a7 100644
--- a/drivers/cpuidle/Kconfig
+++ b/drivers/cpuidle/Kconfig
@@ -19,11 +19,9 @@ config CPU_IDLE_MULTIPLE_DRIVERS
config CPU_IDLE_GOV_LADDER
bool "Ladder governor (for periodic timer tick)"
- default y
config CPU_IDLE_GOV_MENU
bool "Menu governor (for tickless system)"
- default y
config DT_IDLE_STATES
bool
diff --git a/drivers/cpuidle/cpuidle.c b/drivers/cpuidle/cpuidle.c
index 17a6dc0e2111..046423b0c5ca 100644
--- a/drivers/cpuidle/cpuidle.c
+++ b/drivers/cpuidle/cpuidle.c
@@ -79,9 +79,9 @@ static int find_deepest_state(struct cpuidle_driver *drv,
bool freeze)
{
unsigned int latency_req = 0;
- int i, ret = -ENXIO;
+ int i, ret = 0;
- for (i = 0; i < drv->state_count; i++) {
+ for (i = 1; i < drv->state_count; i++) {
struct cpuidle_state *s = &drv->states[i];
struct cpuidle_state_usage *su = &dev->states_usage[i];
@@ -243,7 +243,7 @@ int cpuidle_enter_state(struct cpuidle_device *dev, struct cpuidle_driver *drv,
* @drv: the cpuidle driver
* @dev: the cpuidle device
*
- * Returns the index of the idle state.
+ * Returns the index of the idle state. The return value must not be negative.
*/
int cpuidle_select(struct cpuidle_driver *drv, struct cpuidle_device *dev)
{
diff --git a/drivers/cpuidle/governors/ladder.c b/drivers/cpuidle/governors/ladder.c
index 401c0106ed34..63bd5a403e22 100644
--- a/drivers/cpuidle/governors/ladder.c
+++ b/drivers/cpuidle/governors/ladder.c
@@ -17,6 +17,7 @@
#include <linux/pm_qos.h>
#include <linux/module.h>
#include <linux/jiffies.h>
+#include <linux/tick.h>
#include <asm/io.h>
#include <asm/uaccess.h>
@@ -184,6 +185,14 @@ static struct cpuidle_governor ladder_governor = {
*/
static int __init init_ladder(void)
{
+ /*
+ * When NO_HZ is disabled, or when booting with nohz=off, the ladder
+ * governor is better so give it a higher rating than the menu
+ * governor.
+ */
+ if (!tick_nohz_enabled)
+ ladder_governor.rating = 25;
+
return cpuidle_register_governor(&ladder_governor);
}
diff --git a/drivers/cpuidle/governors/menu.c b/drivers/cpuidle/governors/menu.c
index 7b0971d97cc3..0742b3296673 100644
--- a/drivers/cpuidle/governors/menu.c
+++ b/drivers/cpuidle/governors/menu.c
@@ -294,8 +294,6 @@ static int menu_select(struct cpuidle_driver *drv, struct cpuidle_device *dev)
data->needs_update = 0;
}
- data->last_state_idx = CPUIDLE_DRIVER_STATE_START - 1;
-
/* Special case when user has set very strict latency requirement */
if (unlikely(latency_req == 0))
return 0;
@@ -326,20 +324,25 @@ static int menu_select(struct cpuidle_driver *drv, struct cpuidle_device *dev)
if (latency_req > interactivity_req)
latency_req = interactivity_req;
- /*
- * We want to default to C1 (hlt), not to busy polling
- * unless the timer is happening really really soon.
- */
- if (interactivity_req > 20 &&
- !drv->states[CPUIDLE_DRIVER_STATE_START].disabled &&
- dev->states_usage[CPUIDLE_DRIVER_STATE_START].disable == 0)
+ if (CPUIDLE_DRIVER_STATE_START > 0) {
+ data->last_state_idx = CPUIDLE_DRIVER_STATE_START - 1;
+ /*
+ * We want to default to C1 (hlt), not to busy polling
+ * unless the timer is happening really really soon.
+ */
+ if (interactivity_req > 20 &&
+ !drv->states[CPUIDLE_DRIVER_STATE_START].disabled &&
+ dev->states_usage[CPUIDLE_DRIVER_STATE_START].disable == 0)
+ data->last_state_idx = CPUIDLE_DRIVER_STATE_START;
+ } else {
data->last_state_idx = CPUIDLE_DRIVER_STATE_START;
+ }
/*
* Find the idle state with the lowest power while satisfying
* our constraints.
*/
- for (i = CPUIDLE_DRIVER_STATE_START; i < drv->state_count; i++) {
+ for (i = data->last_state_idx + 1; i < drv->state_count; i++) {
struct cpuidle_state *s = &drv->states[i];
struct cpuidle_state_usage *su = &dev->states_usage[i];