diff options
| -rw-r--r-- | drivers/cpuidle/Kconfig | 2 | ||||
| -rw-r--r-- | drivers/cpuidle/cpuidle.c | 6 | ||||
| -rw-r--r-- | drivers/cpuidle/governors/ladder.c | 9 | ||||
| -rw-r--r-- | drivers/cpuidle/governors/menu.c | 23 | ||||
| -rw-r--r-- | include/linux/tick.h | 2 | ||||
| -rw-r--r-- | kernel/sched/idle.c | 6 | ||||
| -rw-r--r-- | kernel/time/tick-sched.c | 2 |
7 files changed, 28 insertions, 22 deletions
diff --git a/drivers/cpuidle/Kconfig b/drivers/cpuidle/Kconfig index 8c7930b..7e48eb5 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 17a6dc0..046423b 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 401c010..63bd5a4 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 7b0971d..0742b32 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]; diff --git a/include/linux/tick.h b/include/linux/tick.h index e312219..97fd4e5 100644 --- a/include/linux/tick.h +++ b/include/linux/tick.h @@ -98,6 +98,7 @@ static inline void tick_broadcast_exit(void) } #ifdef CONFIG_NO_HZ_COMMON +extern int tick_nohz_enabled; extern int tick_nohz_tick_stopped(void); extern void tick_nohz_idle_enter(void); extern void tick_nohz_idle_exit(void); @@ -106,6 +107,7 @@ extern ktime_t tick_nohz_get_sleep_length(void); extern u64 get_cpu_idle_time_us(int cpu, u64 *last_update_time); extern u64 get_cpu_iowait_time_us(int cpu, u64 *last_update_time); #else /* !CONFIG_NO_HZ_COMMON */ +#define tick_nohz_enabled (0) static inline int tick_nohz_tick_stopped(void) { return 0; } static inline void tick_nohz_idle_enter(void) { } static inline void tick_nohz_idle_exit(void) { } diff --git a/kernel/sched/idle.c b/kernel/sched/idle.c index 4a2ef5a..34852ee 100644 --- a/kernel/sched/idle.c +++ b/kernel/sched/idle.c @@ -97,12 +97,6 @@ void default_idle_call(void) static int call_cpuidle(struct cpuidle_driver *drv, struct cpuidle_device *dev, int next_state) { - /* Fall back to the default arch idle method on errors. */ - if (next_state < 0) { - default_idle_call(); - return next_state; - } - /* * The idle task must be scheduled, it is pointless to go to idle, just * update no idle residency and return. diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c index 9cc20af..9d7a053 100644 --- a/kernel/time/tick-sched.c +++ b/kernel/time/tick-sched.c @@ -387,7 +387,7 @@ void __init tick_nohz_init(void) /* * NO HZ enabled ? */ -static int tick_nohz_enabled __read_mostly = 1; +int tick_nohz_enabled __read_mostly = 1; unsigned long tick_nohz_active __read_mostly; /* * Enable / Disable tickless mode |