diff options
Diffstat (limited to 'drivers/cpuidle')
| -rw-r--r-- | drivers/cpuidle/Kconfig | 19 | ||||
| -rw-r--r-- | drivers/cpuidle/Makefile | 2 | ||||
| -rw-r--r-- | drivers/cpuidle/coupled.c | 2 | ||||
| -rw-r--r-- | drivers/cpuidle/cpuidle-calxeda.c | 161 | ||||
| -rw-r--r-- | drivers/cpuidle/cpuidle.c | 72 | ||||
| -rw-r--r-- | drivers/cpuidle/cpuidle.h | 13 | ||||
| -rw-r--r-- | drivers/cpuidle/driver.c | 222 | ||||
| -rw-r--r-- | drivers/cpuidle/governors/menu.c | 174 | ||||
| -rw-r--r-- | drivers/cpuidle/sysfs.c | 199 |
9 files changed, 725 insertions, 139 deletions
diff --git a/drivers/cpuidle/Kconfig b/drivers/cpuidle/Kconfig index a76b689e553b..c4cc27e5c8a5 100644 --- a/drivers/cpuidle/Kconfig +++ b/drivers/cpuidle/Kconfig @@ -9,6 +9,15 @@ config CPU_IDLE If you're using an ACPI-enabled platform, you should say Y here. +config CPU_IDLE_MULTIPLE_DRIVERS + bool "Support multiple cpuidle drivers" + depends on CPU_IDLE + default n + help + Allows the cpuidle framework to use different drivers for each CPU. + This is useful if you have a system with different CPU latencies and + states. If unsure say N. + config CPU_IDLE_GOV_LADDER bool depends on CPU_IDLE @@ -21,3 +30,13 @@ config CPU_IDLE_GOV_MENU config ARCH_NEEDS_CPU_IDLE_COUPLED def_bool n + +if CPU_IDLE + +config CPU_IDLE_CALXEDA + bool "CPU Idle Driver for Calxeda processors" + depends on ARCH_HIGHBANK + help + Select this to enable cpuidle on Calxeda processors. + +endif diff --git a/drivers/cpuidle/Makefile b/drivers/cpuidle/Makefile index 38c8f69f30cf..03ee87482c71 100644 --- a/drivers/cpuidle/Makefile +++ b/drivers/cpuidle/Makefile @@ -4,3 +4,5 @@ obj-y += cpuidle.o driver.o governor.o sysfs.o governors/ obj-$(CONFIG_ARCH_NEEDS_CPU_IDLE_COUPLED) += coupled.o + +obj-$(CONFIG_CPU_IDLE_CALXEDA) += cpuidle-calxeda.o diff --git a/drivers/cpuidle/coupled.c b/drivers/cpuidle/coupled.c index 3265844839bf..2a297f86dbad 100644 --- a/drivers/cpuidle/coupled.c +++ b/drivers/cpuidle/coupled.c @@ -209,7 +209,7 @@ inline int cpuidle_coupled_set_not_ready(struct cpuidle_coupled *coupled) int all; int ret; - all = coupled->online_count || (coupled->online_count << WAITING_BITS); + all = coupled->online_count | (coupled->online_count << WAITING_BITS); ret = atomic_add_unless(&coupled->ready_waiting_counts, -MAX_WAITING_CPUS, all); diff --git a/drivers/cpuidle/cpuidle-calxeda.c b/drivers/cpuidle/cpuidle-calxeda.c new file mode 100644 index 000000000000..e1aab38c5a8d --- /dev/null +++ b/drivers/cpuidle/cpuidle-calxeda.c @@ -0,0 +1,161 @@ +/* + * Copyright 2012 Calxeda, Inc. + * + * Based on arch/arm/plat-mxc/cpuidle.c: + * Copyright 2012 Freescale Semiconductor, Inc. + * Copyright 2012 Linaro Ltd. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms and conditions of the GNU General Public License, + * version 2, as published by the Free Software Foundation. + * + * This program is distributed in the hope it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for + * more details. + * + * You should have received a copy of the GNU General Public License along with + * this program. If not, see <http://www.gnu.org/licenses/>. + */ + +#include <linux/cpuidle.h> +#include <linux/init.h> +#include <linux/io.h> +#include <linux/of.h> +#include <linux/time.h> +#include <linux/delay.h> +#include <linux/suspend.h> +#include <asm/cpuidle.h> +#include <asm/proc-fns.h> +#include <asm/smp_scu.h> +#include <asm/suspend.h> +#include <asm/cacheflush.h> +#include <asm/cp15.h> + +extern void highbank_set_cpu_jump(int cpu, void *jump_addr); +extern void *scu_base_addr; + +static struct cpuidle_device __percpu *calxeda_idle_cpuidle_devices; + +static inline unsigned int get_auxcr(void) +{ + unsigned int val; + asm("mrc p15, 0, %0, c1, c0, 1 @ get AUXCR" : "=r" (val) : : "cc"); + return val; +} + +static inline void set_auxcr(unsigned int val) +{ + asm volatile("mcr p15, 0, %0, c1, c0, 1 @ set AUXCR" + : : "r" (val) : "cc"); + isb(); +} + +static noinline void calxeda_idle_restore(void) +{ + set_cr(get_cr() | CR_C); + set_auxcr(get_auxcr() | 0x40); + scu_power_mode(scu_base_addr, SCU_PM_NORMAL); +} + +static int calxeda_idle_finish(unsigned long val) +{ + /* Already flushed cache, but do it again as the outer cache functions + * dirty the cache with spinlocks */ + flush_cache_all(); + + set_auxcr(get_auxcr() & ~0x40); + set_cr(get_cr() & ~CR_C); + + scu_power_mode(scu_base_addr, SCU_PM_DORMANT); + + cpu_do_idle(); + + /* Restore things if we didn't enter power-gating */ + calxeda_idle_restore(); + return 1; +} + +static int calxeda_pwrdown_idle(struct cpuidle_device *dev, + struct cpuidle_driver *drv, + int index) +{ + highbank_set_cpu_jump(smp_processor_id(), cpu_resume); + cpu_suspend(0, calxeda_idle_finish); + return index; +} + +static void calxeda_idle_cpuidle_devices_uninit(void) +{ + int i; + struct cpuidle_device *dev; + + for_each_possible_cpu(i) { + dev = per_cpu_ptr(calxeda_idle_cpuidle_devices, i); + cpuidle_unregister_device(dev); + } + + free_percpu(calxeda_idle_cpuidle_devices); +} + +static struct cpuidle_driver calxeda_idle_driver = { + .name = "calxeda_idle", + .en_core_tk_irqen = 1, + .states = { + ARM_CPUIDLE_WFI_STATE, + { + .name = "PG", + .desc = "Power Gate", + .flags = CPUIDLE_FLAG_TIME_VALID, + .exit_latency = 30, + .power_usage = 50, + .target_residency = 200, + .enter = calxeda_pwrdown_idle, + }, + }, + .state_count = 2, +}; + +static int __init calxeda_cpuidle_init(void) +{ + int cpu_id; + int ret; + struct cpuidle_device *dev; + struct cpuidle_driver *drv = &calxeda_idle_driver; + + if (!of_machine_is_compatible("calxeda,highbank")) + return -ENODEV; + + ret = cpuidle_register_driver(drv); + if (ret) + return ret; + + calxeda_idle_cpuidle_devices = alloc_percpu(struct cpuidle_device); + if (calxeda_idle_cpuidle_devices == NULL) { + ret = -ENOMEM; + goto unregister_drv; + } + + /* initialize state data for each cpuidle_device */ + for_each_possible_cpu(cpu_id) { + dev = per_cpu_ptr(calxeda_idle_cpuidle_devices, cpu_id); + dev->cpu = cpu_id; + dev->state_count = drv->state_count; + + ret = cpuidle_register_device(dev); + if (ret) { + pr_err("Failed to register cpu %u, error: %d\n", + cpu_id, ret); + goto uninit; + } + } + + return 0; + +uninit: + calxeda_idle_cpuidle_devices_uninit(); +unregister_drv: + cpuidle_unregister_driver(drv); + return ret; +} +module_init(calxeda_cpuidle_init); diff --git a/drivers/cpuidle/cpuidle.c b/drivers/cpuidle/cpuidle.c index 7f15b8514a18..e1f6860e069c 100644 --- a/drivers/cpuidle/cpuidle.c +++ b/drivers/cpuidle/cpuidle.c @@ -68,25 +68,16 @@ static cpuidle_enter_t cpuidle_enter_ops; int cpuidle_play_dead(void) { struct cpuidle_device *dev = __this_cpu_read(cpuidle_devices); - struct cpuidle_driver *drv = cpuidle_get_driver(); - int i, dead_state = -1; - int power_usage = -1; + struct cpuidle_driver *drv = cpuidle_get_cpu_driver(dev); + int i; if (!drv) return -ENODEV; /* Find lowest-power state that supports long-term idle */ - for (i = CPUIDLE_DRIVER_STATE_START; i < drv->state_count; i++) { - struct cpuidle_state *s = &drv->states[i]; - - if (s->power_usage < power_usage && s->enter_dead) { - power_usage = s->power_usage; - dead_state = i; - } - } - - if (dead_state != -1) - return drv->states[dead_state].enter_dead(dev, dead_state); + for (i = drv->state_count - 1; i >= CPUIDLE_DRIVER_STATE_START; i--) + if (drv->states[i].enter_dead) + return drv->states[i].enter_dead(dev, i); return -ENODEV; } @@ -109,8 +100,7 @@ int cpuidle_enter_state(struct cpuidle_device *dev, struct cpuidle_driver *drv, /* This can be moved to within driver enter routine * but that results in multiple copies of same code. */ - dev->states_usage[entered_state].time += - (unsigned long long)dev->last_residency; + dev->states_usage[entered_state].time += dev->last_residency; dev->states_usage[entered_state].usage++; } else { dev->last_residency = 0; @@ -128,7 +118,7 @@ int cpuidle_enter_state(struct cpuidle_device *dev, struct cpuidle_driver *drv, int cpuidle_idle_call(void) { struct cpuidle_device *dev = __this_cpu_read(cpuidle_devices); - struct cpuidle_driver *drv = cpuidle_get_driver(); + struct cpuidle_driver *drv; int next_state, entered_state; if (off) @@ -141,9 +131,15 @@ int cpuidle_idle_call(void) if (!dev || !dev->enabled) return -EBUSY; + drv = cpuidle_get_cpu_driver(dev); + /* ask the governor for the next state */ next_state = cpuidle_curr_governor->select(drv, dev); if (need_resched()) { + dev->last_residency = 0; + /* give the governor an opportunity to reflect on the outcome */ + if (cpuidle_curr_governor->reflect) + cpuidle_curr_governor->reflect(dev, next_state); local_irq_enable(); return 0; } @@ -308,15 +304,19 @@ static void poll_idle_init(struct cpuidle_driver *drv) {} int cpuidle_enable_device(struct cpuidle_device *dev) { int ret, i; - struct cpuidle_driver *drv = cpuidle_get_driver(); + struct cpuidle_driver *drv; if (!dev) return -EINVAL; if (dev->enabled) return 0; + + drv = cpuidle_get_cpu_driver(dev); + if (!drv || !cpuidle_curr_governor) return -EIO; + if (!dev->state_count) dev->state_count = drv->state_count; @@ -331,7 +331,8 @@ int cpuidle_enable_device(struct cpuidle_device *dev) poll_idle_init(drv); - if ((ret = cpuidle_add_state_sysfs(dev))) + ret = cpuidle_add_device_sysfs(dev); + if (ret) return ret; if (cpuidle_curr_governor->enable && @@ -352,7 +353,7 @@ int cpuidle_enable_device(struct cpuidle_device *dev) return 0; fail_sysfs: - cpuidle_remove_state_sysfs(dev); + cpuidle_remove_device_sysfs(dev); return ret; } @@ -368,17 +369,20 @@ EXPORT_SYMBOL_GPL(cpuidle_enable_device); */ void cpuidle_disable_device(struct cpuidle_device *dev) { + struct cpuidle_driver *drv = cpuidle_get_cpu_driver(dev); + if (!dev || !dev->enabled) return; - if (!cpuidle_get_driver() || !cpuidle_curr_governor) + + if (!drv || !cpuidle_curr_governor) return; dev->enabled = 0; if (cpuidle_curr_governor->disable) - cpuidle_curr_governor->disable(cpuidle_get_driver(), dev); + cpuidle_curr_governor->disable(drv, dev); - cpuidle_remove_state_sysfs(dev); + cpuidle_remove_device_sysfs(dev); enabled_devices--; } @@ -394,17 +398,14 @@ EXPORT_SYMBOL_GPL(cpuidle_disable_device); static int __cpuidle_register_device(struct cpuidle_device *dev) { int ret; - struct device *cpu_dev = get_cpu_device((unsigned long)dev->cpu); - struct cpuidle_driver *cpuidle_driver = cpuidle_get_driver(); + struct cpuidle_driver *drv = cpuidle_get_cpu_driver(dev); - if (!try_module_get(cpuidle_driver->owner)) + if (!try_module_get(drv->owner)) return -EINVAL; - init_completion(&dev->kobj_unregister); - per_cpu(cpuidle_devices, dev->cpu) = dev; list_add(&dev->device_list, &cpuidle_detected_devices); - ret = cpuidle_add_sysfs(cpu_dev); + ret = cpuidle_add_sysfs(dev); if (ret) goto err_sysfs; @@ -416,12 +417,11 @@ static int __cpuidle_register_device(struct cpuidle_device *dev) return 0; err_coupled: - cpuidle_remove_sysfs(cpu_dev); - wait_for_completion(&dev->kobj_unregister); + cpuidle_remove_sysfs(dev); err_sysfs: list_del(&dev->device_list); per_cpu(cpuidle_devices, dev->cpu) = NULL; - module_put(cpuidle_driver->owner); + module_put(drv->owner); return ret; } @@ -460,8 +460,7 @@ EXPORT_SYMBOL_GPL(cpuidle_register_device); */ void cpuidle_unregister_device(struct cpuidle_device *dev) { - struct device *cpu_dev = get_cpu_device((unsigned long)dev->cpu); - struct cpuidle_driver *cpuidle_driver = cpuidle_get_driver(); + struct cpuidle_driver *drv = cpuidle_get_cpu_driver(dev); if (dev->registered == 0) return; @@ -470,16 +469,15 @@ void cpuidle_unregister_device(struct cpuidle_device *dev) cpuidle_disable_device(dev); - cpuidle_remove_sysfs(cpu_dev); + cpuidle_remove_sysfs(dev); list_del(&dev->device_list); - wait_for_completion(&dev->kobj_unregister); per_cpu(cpuidle_devices, dev->cpu) = NULL; cpuidle_coupled_unregister_device(dev); cpuidle_resume_and_unlock(); - module_put(cpuidle_driver->owner); + module_put(drv->owner); } EXPORT_SYMBOL_GPL(cpuidle_unregister_device); diff --git a/drivers/cpuidle/cpuidle.h b/drivers/cpuidle/cpuidle.h index 76e7f696ad8c..ee97e9672ecf 100644 --- a/drivers/cpuidle/cpuidle.h +++ b/drivers/cpuidle/cpuidle.h @@ -5,8 +5,6 @@ #ifndef __DRIVER_CPUIDLE_H #define __DRIVER_CPUIDLE_H -#include <linux/device.h> - /* For internal use only */ extern struct cpuidle_governor *cpuidle_curr_governor; extern struct list_head cpuidle_governors; @@ -25,12 +23,15 @@ extern void cpuidle_uninstall_idle_handler(void); extern int cpuidle_switch_governor(struct cpuidle_governor *gov); /* sysfs */ + +struct device; + extern int cpuidle_add_interface(struct device *dev); extern void cpuidle_remove_interface(struct device *dev); -extern int cpuidle_add_state_sysfs(struct cpuidle_device *device); -extern void cpuidle_remove_state_sysfs(struct cpuidle_device *device); -extern int cpuidle_add_sysfs(struct device *dev); -extern void cpuidle_remove_sysfs(struct device *dev); +extern int cpuidle_add_device_sysfs(struct cpuidle_device *device); +extern void cpuidle_remove_device_sysfs(struct cpuidle_device *device); +extern int cpuidle_add_sysfs(struct cpuidle_device *dev); +extern void cpuidle_remove_sysfs(struct cpuidle_device *dev); #ifdef CONFIG_ARCH_NEEDS_CPU_IDLE_COUPLED bool cpuidle_state_is_coupled(struct cpuidle_device *dev, diff --git a/drivers/cpuidle/driver.c b/drivers/cpuidle/driver.c index 87db3877fead..422c7b69ba7c 100644 --- a/drivers/cpuidle/driver.c +++ b/drivers/cpuidle/driver.c @@ -14,37 +14,17 @@ #include "cpuidle.h" -static struct cpuidle_driver *cpuidle_curr_driver; DEFINE_SPINLOCK(cpuidle_driver_lock); -int cpuidle_driver_refcount; - -static void set_power_states(struct cpuidle_driver *drv) -{ - int i; - - /* - * cpuidle driver should set the drv->power_specified bit - * before registering if the driver provides - * power_usage numbers. - * - * If power_specified is not set, - * we fill in power_usage with decreasing values as the - * cpuidle code has an implicit assumption that state Cn - * uses less power than C(n-1). - * - * With CONFIG_ARCH_HAS_CPU_RELAX, C0 is already assigned - * an power value of -1. So we use -2, -3, etc, for other - * c-states. - */ - for (i = CPUIDLE_DRIVER_STATE_START; i < drv->state_count; i++) - drv->states[i].power_usage = -1 - i; + +static void __cpuidle_set_cpu_driver(struct cpuidle_driver *drv, int cpu); +static struct cpuidle_driver * __cpuidle_get_cpu_driver(int cpu); + +static void __cpuidle_driver_init(struct cpuidle_driver *drv) +{ + drv->refcnt = 0; } -/** - * cpuidle_register_driver - registers a driver - * @drv: the driver - */ -int cpuidle_register_driver(struct cpuidle_driver *drv) +static int __cpuidle_register_driver(struct cpuidle_driver *drv, int cpu) { if (!drv || !drv->state_count) return -EINVAL; @@ -52,31 +32,101 @@ int cpuidle_register_driver(struct cpuidle_driver *drv) if (cpuidle_disabled()) return -ENODEV; - spin_lock(&cpuidle_driver_lock); - if (cpuidle_curr_driver) { - spin_unlock(&cpuidle_driver_lock); + if (__cpuidle_get_cpu_driver(cpu)) return -EBUSY; + + __cpuidle_driver_init(drv); + + __cpuidle_set_cpu_driver(drv, cpu); + + return 0; +} + +static void __cpuidle_unregister_driver(struct cpuidle_driver *drv, int cpu) +{ + if (drv != __cpuidle_get_cpu_driver(cpu)) + return; + + if (!WARN_ON(drv->refcnt > 0)) + __cpuidle_set_cpu_driver(NULL, cpu); +} + +#ifdef CONFIG_CPU_IDLE_MULTIPLE_DRIVERS + +static DEFINE_PER_CPU(struct cpuidle_driver *, cpuidle_drivers); + +static void __cpuidle_set_cpu_driver(struct cpuidle_driver *drv, int cpu) +{ + per_cpu(cpuidle_drivers, cpu) = drv; +} + +static struct cpuidle_driver *__cpuidle_get_cpu_driver(int cpu) +{ + return per_cpu(cpuidle_drivers, cpu); +} + +static void __cpuidle_unregister_all_cpu_driver(struct cpuidle_driver *drv) +{ + int cpu; + for_each_present_cpu(cpu) + __cpuidle_unregister_driver(drv, cpu); +} + +static int __cpuidle_register_all_cpu_driver(struct cpuidle_driver *drv) +{ + int ret = 0; + int i, cpu; + + for_each_present_cpu(cpu) { + ret = __cpuidle_register_driver(drv, cpu); + if (ret) + break; } - if (!drv->power_specified) - set_power_states(drv); + if (ret) + for_each_present_cpu(i) { + if (i == cpu) + break; + __cpuidle_unregister_driver(drv, i); + } - cpuidle_curr_driver = drv; + return ret; +} + +int cpuidle_register_cpu_driver(struct cpuidle_driver *drv, int cpu) +{ + int ret; + + spin_lock(&cpuidle_driver_lock); + ret = __cpuidle_register_driver(drv, cpu); spin_unlock(&cpuidle_driver_lock); - return 0; + return ret; +} + +void cpuidle_unregister_cpu_driver(struct cpuidle_driver *drv, int cpu) +{ + spin_lock(&cpuidle_driver_lock); + __cpuidle_unregister_driver(drv, cpu); + spin_unlock(&cpuidle_driver_lock); } -EXPORT_SYMBOL_GPL(cpuidle_register_driver); /** - * cpuidle_get_driver - return the current driver + * cpuidle_register_driver - registers a driver + * @drv: the driver */ -struct cpuidle_driver *cpuidle_get_driver(void) +int cpuidle_register_driver(struct cpuidle_driver *drv) { - return cpuidle_curr_driver; + int ret; + + spin_lock(&cpuidle_driver_lock); + ret = __cpuidle_register_all_cpu_driver(drv); + spin_unlock(&cpuidle_driver_lock); + + return ret; } -EXPORT_SYMBOL_GPL(cpuidle_get_driver); +EXPORT_SYMBOL_GPL(cpuidle_register_driver); /** * cpuidle_unregister_driver - unregisters a driver @@ -84,20 +134,88 @@ EXPORT_SYMBOL_GPL(cpuidle_get_driver); */ void cpuidle_unregister_driver(struct cpuidle_driver *drv) { - if (drv != cpuidle_curr_driver) { - WARN(1, "invalid cpuidle_unregister_driver(%s)\n", - drv->name); - return; - } + spin_lock(&cpuidle_driver_lock); + __cpuidle_unregister_all_cpu_driver(drv); + spin_unlock(&cpuidle_driver_lock); +} +EXPORT_SYMBOL_GPL(cpuidle_unregister_driver); + +#else + +static struct cpuidle_driver *cpuidle_curr_driver; + +static inline void __cpuidle_set_cpu_driver(struct cpuidle_driver *drv, int cpu) +{ + cpuidle_curr_driver = drv; +} + +static inline struct cpuidle_driver *__cpuidle_get_cpu_driver(int cpu) +{ + return cpuidle_curr_driver; +} + +/** + * cpuidle_register_driver - registers a driver + * @drv: the driver + */ +int cpuidle_register_driver(struct cpuidle_driver *drv) +{ + int ret, cpu; + cpu = get_cpu(); spin_lock(&cpuidle_driver_lock); + ret = __cpuidle_register_driver(drv, cpu); + spin_unlock(&cpuidle_driver_lock); + put_cpu(); + + return ret; +} +EXPORT_SYMBOL_GPL(cpuidle_register_driver); - if (!WARN_ON(cpuidle_driver_refcount > 0)) - cpuidle_curr_driver = NULL; +/** + * cpuidle_unregister_driver - unregisters a driver + * @drv: the driver + */ +void cpuidle_unregister_driver(struct cpuidle_driver *drv) +{ + int cpu; + cpu = get_cpu(); + spin_lock(&cpuidle_driver_lock); + __cpuidle_unregister_driver(drv, cpu); spin_unlock(&cpuidle_driver_lock); + put_cpu(); } EXPORT_SYMBOL_GPL(cpuidle_unregister_driver); +#endif + +/** + * cpuidle_get_driver - return the current driver + */ +struct cpuidle_driver *cpuidle_get_driver(void) +{ + struct cpuidle_driver *drv; + int cpu; + + cpu = get_cpu(); + drv = __cpuidle_get_cpu_driver(cpu); + put_cpu(); + + return drv; +} +EXPORT_SYMBOL_GPL(cpuidle_get_driver); + +/** + * cpuidle_get_cpu_driver - return the driver tied with a cpu + */ +struct cpuidle_driver *cpuidle_get_cpu_driver(struct cpuidle_device *dev) +{ + if (!dev) + return NULL; + + return __cpuidle_get_cpu_driver(dev->cpu); +} +EXPORT_SYMBOL_GPL(cpuidle_get_cpu_driver); struct cpuidle_driver *cpuidle_driver_ref(void) { @@ -105,8 +223,8 @@ struct cpuidle_driver *cpuidle_driver_ref(void) spin_lock(&cpuidle_driver_lock); - drv = cpuidle_curr_driver; - cpuidle_driver_refcount++; + drv = cpuidle_get_driver(); + drv->refcnt++; spin_unlock(&cpuidle_driver_lock); return drv; @@ -114,10 +232,12 @@ struct cpuidle_driver *cpuidle_driver_ref(void) void cpuidle_driver_unref(void) { + struct cpuidle_driver *drv = cpuidle_get_driver(); + spin_lock(&cpuidle_driver_lock); - if (!WARN_ON(cpuidle_driver_refcount <= 0)) - cpuidle_driver_refcount--; + if (drv && !WARN_ON(drv->refcnt <= 0)) + drv->refcnt--; spin_unlock(&cpuidle_driver_lock); } diff --git a/drivers/cpuidle/governors/menu.c b/drivers/cpuidle/governors/menu.c index 5b1f2c372c1f..fe343a06b7da 100644 --- a/drivers/cpuidle/governors/menu.c +++ b/drivers/cpuidle/governors/menu.c @@ -28,6 +28,13 @@ #define MAX_INTERESTING 50000 #define STDDEV_THRESH 400 +/* 60 * 60 > STDDEV_THRESH * INTERVALS = 400 * 8 */ +#define MAX_DEVIATION 60 + +static DEFINE_PER_CPU(struct hrtimer, menu_hrtimer); +static DEFINE_PER_CPU(int, hrtimer_status); +/* menu hrtimer mode */ +enum {MENU_HRTIMER_STOP, MENU_HRTIMER_REPEAT, MENU_HRTIMER_GENERAL}; /* * Concepts and ideas behind the menu governor @@ -109,6 +116,13 @@ * */ +/* + * The C-state residency is so long that is is worthwhile to exit + * from the shallow C-state and re-enter into a deeper C-state. + */ +static unsigned int perfect_cstate_ms __read_mostly = 30; +module_param(perfect_cstate_ms, uint, 0000); + struct menu_device { int last_state_idx; int needs_update; @@ -191,40 +205,102 @@ static u64 div_round64(u64 dividend, u32 divisor) return div_u64(dividend + (divisor / 2), divisor); } +/* Cancel the hrtimer if it is not triggered yet */ +void menu_hrtimer_cancel(void) +{ + int cpu = smp_processor_id(); + struct hrtimer *hrtmr = &per_cpu(menu_hrtimer, cpu); + + /* The timer is still not time out*/ + if (per_cpu(hrtimer_status, cpu)) { + hrtimer_cancel(hrtmr); + per_cpu(hrtimer_status, cpu) = MENU_HRTIMER_STOP; + } +} +EXPORT_SYMBOL_GPL(menu_hrtimer_cancel); + +/* Call back for hrtimer is triggered */ +static enum hrtimer_restart menu_hrtimer_notify(struct hrtimer *hrtimer) +{ + int cpu = smp_processor_id(); + struct menu_device *data = &per_cpu(menu_devices, cpu); + + /* In general case, the expected residency is much larger than + * deepest C-state target residency, but prediction logic still + * predicts a small predicted residency, so the prediction + * history is totally broken if the timer is triggered. + * So reset the correction factor. + */ + if (per_cpu(hrtimer_status, cpu) == MENU_HRTIMER_GENERAL) + data->correction_factor[data->bucket] = RESOLUTION * DECAY; + + per_cpu(hrtimer_status, cpu) = MENU_HRTIMER_STOP; + + return HRTIMER_NORESTART; +} + /* * Try detecting repeating patterns by keeping track of the last 8 * intervals, and checking if the standard deviation of that set * of points is below a threshold. If it is... then use the * average of these 8 points as the estimated value. */ -static void detect_repeating_patterns(struct menu_device *data) +static u32 get_typical_interval(struct menu_device *data) { - int i; - uint64_t avg = 0; - uint64_t stddev = 0; /* contains the square of the std deviation */ - - /* first calculate average and standard deviation of the past */ - for (i = 0; i < INTERVALS; i++) - avg += data->intervals[i]; - avg = avg / INTERVALS; - - /* if the avg is beyond the known next tick, it's worthless */ - if (avg > data->expected_us) - return; + int i = 0, divisor = 0; + uint64_t max = 0, avg = 0, stddev = 0; + int64_t thresh = LLONG_MAX; /* Discard outliers above this value. */ + unsigned int ret = 0; - for (i = 0; i < INTERVALS; i++) - stddev += (data->intervals[i] - avg) * - (data->intervals[i] - avg); +again: - stddev = stddev / INTERVALS; + /* first calculate average and standard deviation of the past */ + max = avg = divisor = stddev = 0; + for (i = 0; i < INTERVALS; i++) { + int64_t value = data->intervals[i]; + if (value <= thresh) { + avg += value; + divisor++; + if (value > max) + max = value; + } + } + do_div(avg, divisor); + for (i = 0; i < INTERVALS; i++) { + int64_t value = data->intervals[i]; + if (value <= thresh) { + int64_t diff = value - avg; + stddev += diff * diff; + } + } + do_div(stddev, divisor); + stddev = int_sqrt(stddev); /* - * now.. if stddev is small.. then assume we have a - * repeating pattern and predict we keep doing this. + * If we have outliers to the upside in our distribution, discard + * those by setting the threshold to exclude these outliers, then + * calculate the average and standard deviation again. Once we get + * down to the bottom 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. + * + * The typical interval is obtained when standard deviation is small + * or standard deviation is small compared to the average interval. */ - - if (avg && stddev < STDDEV_THRESH) + if (((avg > stddev * 6) && (divisor * 4 >= INTERVALS * 3)) + || stddev <= 20) { data->predicted_us = avg; + ret = 1; + return ret; + + } else if ((divisor * 4) > INTERVALS * 3) { + /* Exclude the max interval */ + thresh = max - 1; + goto again; + } + + return ret; } /** @@ -236,10 +312,12 @@ static int menu_select(struct cpuidle_driver *drv, struct cpuidle_device *dev) { struct menu_device *data = &__get_cpu_var(menu_devices); int latency_req = pm_qos_request(PM_QOS_CPU_DMA_LATENCY); - int power_usage = -1; int i; int multiplier; struct timespec t; + int repeat = 0, low_predicted = 0; + int cpu = smp_processor_id(); + struct hrtimer *hrtmr = &per_cpu(menu_hrtimer, cpu); if (data->needs_update) { menu_update(drv, dev); @@ -274,7 +352,7 @@ static int menu_select(struct cpuidle_driver *drv, struct cpuidle_device *dev) data->predicted_us = div_round64(data->expected_us * data->correction_factor[data->bucket], RESOLUTION * DECAY); - detect_repeating_patterns(data); + repeat = get_typical_interval(data); /* * We want to default to C1 (hlt), not to busy polling @@ -295,18 +373,55 @@ static int menu_select(struct cpuidle_driver *drv, struct cpuidle_device *dev) if (s->disabled || su->disable) continue; - if (s->target_residency > data->predicted_us) + if (s->target_residency > data->predicted_us) { + low_predicted = 1; continue; + } if (s->exit_latency > latency_req) continue; if (s->exit_latency * multiplier > data->predicted_us) continue; - if (s->power_usage < power_usage) { - power_usage = s->power_usage; - data->last_state_idx = i; - data->exit_us = s->exit_latency; + data->last_state_idx = i; + data->exit_us = s->exit_latency; + } + + /* not deepest C-state chosen for low predicted residency */ + if (low_predicted) { + unsigned int timer_us = 0; + unsigned int perfect_us = 0; + + /* + * Set a timer to detect whether this sleep is much + * longer than repeat mode predicted. If the timer + * triggers, the code will evaluate whether to put + * the CPU into a deeper C-state. + * The timer is cancelled on CPU wakeup. + */ + timer_us = 2 * (data->predicted_us + MAX_DEVIATION); + + perfect_us = perfect_cstate_ms * 1000; + + if (repeat && (4 * timer_us < data->expected_us)) { + RCU_NONIDLE(hrtimer_start(hrtmr, + ns_to_ktime(1000 * timer_us), + HRTIMER_MODE_REL_PINNED)); + /* In repeat case, menu hrtimer is started */ + per_cpu(hrtimer_status, cpu) = MENU_HRTIMER_REPEAT; + } else if (perfect_us < data->expected_us) { + /* + * The next timer is long. This could be because + * we did not make a useful prediction. + * In that case, it makes sense to re-enter + * into a deeper C-state after some time. + */ + RCU_NONIDLE(hrtimer_start(hrtmr, + ns_to_ktime(1000 * timer_us), + HRTIMER_MODE_REL_PINNED)); + /* In general case, menu hrtimer is started */ + per_cpu(hrtimer_status, cpu) = MENU_HRTIMER_GENERAL; } + } return data->last_state_idx; @@ -399,6 +514,9 @@ static int menu_enable_device(struct cpuidle_driver *drv, struct cpuidle_device *dev) { struct menu_device *data = &per_cpu(menu_devices, dev->cpu); + struct hrtimer *t = &per_cpu(menu_hrtimer, dev->cpu); + hrtimer_init(t, CLOCK_MONOTONIC, HRTIMER_MODE_REL); + t->function = menu_hrtimer_notify; memset(data, 0, sizeof(struct menu_device)); diff --git a/drivers/cpuidle/sysfs.c b/drivers/cpuidle/sysfs.c index 5f809e337b89..428754af6236 100644 --- a/drivers/cpuidle/sysfs.c +++ b/drivers/cpuidle/sysfs.c @@ -12,6 +12,7 @@ #include <linux/slab.h> #include <linux/cpu.h> #include <linux/capability.h> +#include <linux/device.h> #include "cpuidle.h" @@ -297,6 +298,13 @@ static struct attribute *cpuidle_state_default_attrs[] = { NULL }; +struct cpuidle_state_kobj { + struct cpuidle_state *state; + struct cpuidle_state_usage *state_usage; + struct completion kobj_unregister; + struct kobject kobj; +}; + #define kobj_to_state_obj(k) container_of(k, struct cpuidle_state_kobj, kobj) #define kobj_to_state(k) (kobj_to_state_obj(k)->state) #define kobj_to_state_usage(k) (kobj_to_state_obj(k)->state_usage) @@ -356,14 +364,14 @@ static inline void cpuidle_free_state_kobj(struct cpuidle_device *device, int i) } /** - * cpuidle_add_driver_sysfs - adds driver-specific sysfs attributes + * cpuidle_add_state_sysfs - adds cpuidle states sysfs attributes * @device: the target device */ -int cpuidle_add_state_sysfs(struct cpuidle_device *device) +static int cpuidle_add_state_sysfs(struct cpuidle_device *device) { int i, ret = -ENOMEM; struct cpuidle_state_kobj *kobj; - struct cpuidle_driver *drv = cpuidle_get_driver(); + struct cpuidle_driver *drv = cpuidle_get_cpu_driver(device); /* state statistics */ for (i = 0; i < device->state_count; i++) { @@ -374,8 +382,8 @@ int cpuidle_add_state_sysfs(struct cpuidle_device *device) kobj->state_usage = &device->states_usage[i]; init_completion(&kobj->kobj_unregister); - ret = kobject_init_and_add(&kobj->kobj, &ktype_state_cpuidle, &device->kobj, - "state%d", i); + ret = kobject_init_and_add(&kobj->kobj, &ktype_state_cpuidle, + &device->kobj, "state%d", i); if (ret) { kfree(kobj); goto error_state; @@ -393,10 +401,10 @@ error_state: } /** - * cpuidle_remove_driver_sysfs - removes driver-specific sysfs attributes + * cpuidle_remove_driver_sysfs - removes the cpuidle states sysfs attributes * @device: the target device */ -void cpuidle_remove_state_sysfs(struct cpuidle_device *device) +static void cpuidle_remove_state_sysfs(struct cpuidle_device *device) { int i; @@ -404,17 +412,179 @@ void cpuidle_remove_state_sysfs(struct cpuidle_device *device) cpuidle_free_state_kobj(device, i); } +#ifdef CONFIG_CPU_IDLE_MULTIPLE_DRIVERS +#define kobj_to_driver_kobj(k) container_of(k, struct cpuidle_driver_kobj, kobj) +#define attr_to_driver_attr(a) container_of(a, struct cpuidle_driver_attr, attr) + +#define define_one_driver_ro(_name, show) \ + static struct cpuidle_driver_attr attr_driver_##_name = \ + __ATTR(_name, 0644, show, NULL) + +struct cpuidle_driver_kobj { + struct cpuidle_driver *drv; + struct completion kobj_unregister; + struct kobject kobj; +}; + +struct cpuidle_driver_attr { + struct attribute attr; + ssize_t (*show)(struct cpuidle_driver *, char *); + ssize_t (*store)(struct cpuidle_driver *, const char *, size_t); +}; + +static ssize_t show_driver_name(struct cpuidle_driver *drv, char *buf) +{ + ssize_t ret; + + spin_lock(&cpuidle_driver_lock); + ret = sprintf(buf, "%s\n", drv ? drv->name : "none"); + spin_unlock(&cpuidle_driver_lock); + + return ret; +} + +static void cpuidle_driver_sysfs_release(struct kobject *kobj) +{ + struct cpuidle_driver_kobj *driver_kobj = kobj_to_driver_kobj(kobj); + complete(&driver_kobj->kobj_unregister); +} + +static ssize_t cpuidle_driver_show(struct kobject *kobj, struct attribute * attr, + char * buf) +{ + int ret = -EIO; + struct cpuidle_driver_kobj *driver_kobj = kobj_to_driver_kobj(kobj); + struct cpuidle_driver_attr *dattr = attr_to_driver_attr(attr); + + if (dattr->show) + ret = dattr->show(driver_kobj->drv, buf); + + return ret; +} + +static ssize_t cpuidle_driver_store(struct kobject *kobj, struct attribute *attr, + const char *buf, size_t size) +{ + int ret = -EIO; + struct cpuidle_driver_kobj *driver_kobj = kobj_to_driver_kobj(kobj); + struct cpuidle_driver_attr *dattr = attr_to_driver_attr(attr); + + if (dattr->store) + ret = dattr->store(driver_kobj->drv, buf, size); + + return ret; +} + +define_one_driver_ro(name, show_driver_name); + +static const struct sysfs_ops cpuidle_driver_sysfs_ops = { + .show = cpuidle_driver_show, + .store = cpuidle_driver_store, +}; + +static struct attribute *cpuidle_driver_default_attrs[] = { + &attr_driver_name.attr, + NULL +}; + +static struct kobj_type ktype_driver_cpuidle = { + .sysfs_ops = &cpuidle_driver_sysfs_ops, + .default_attrs = cpuidle_driver_default_attrs, + .release = cpuidle_driver_sysfs_release, +}; + +/** + * cpuidle_add_driver_sysfs - adds the driver name sysfs attribute + * @device: the target device + */ +static int cpuidle_add_driver_sysfs(struct cpuidle_device *dev) +{ + struct cpuidle_driver_kobj *kdrv; + struct cpuidle_driver *drv = cpuidle_get_cpu_driver(dev); + int ret; + + kdrv = kzalloc(sizeof(*kdrv), GFP_KERNEL); + if (!kdrv) + return -ENOMEM; + + kdrv->drv = drv; + init_completion(&kdrv->kobj_unregister); + + ret = kobject_init_and_add(&kdrv->kobj, &ktype_driver_cpuidle, + &dev->kobj, "driver"); + if (ret) { + kfree(kdrv); + return ret; + } + + kobject_uevent(&kdrv->kobj, KOBJ_ADD); + dev->kobj_driver = kdrv; + + return ret; +} + +/** + * cpuidle_remove_driver_sysfs - removes the driver name sysfs attribute + * @device: the target device + */ +static void cpuidle_remove_driver_sysfs(struct cpuidle_device *dev) +{ + struct cpuidle_driver_kobj *kdrv = dev->kobj_driver; + kobject_put(&kdrv->kobj); + wait_for_completion(&kdrv->kobj_unregister); + kfree(kdrv); +} +#else +static inline int cpuidle_add_driver_sysfs(struct cpuidle_device *dev) +{ + return 0; +} + +static inline void cpuidle_remove_driver_sysfs(struct cpuidle_device *dev) +{ + ; +} +#endif + +/** + * cpuidle_add_device_sysfs - adds device specific sysfs attributes + * @device: the target device + */ +int cpuidle_add_device_sysfs(struct cpuidle_device *device) +{ + int ret; + + ret = cpuidle_add_state_sysfs(device); + if (ret) + return ret; + + ret = cpuidle_add_driver_sysfs(device); + if (ret) + cpuidle_remove_state_sysfs(device); + return ret; +} + +/** + * cpuidle_remove_device_sysfs : removes device specific sysfs attributes + * @device : the target device + */ +void cpuidle_remove_device_sysfs(struct cpuidle_device *device) +{ + cpuidle_remove_driver_sysfs(device); + cpuidle_remove_state_sysfs(device); +} + /** * cpuidle_add_sysfs - creates a sysfs instance for the target device * @dev: the target device */ -int cpuidle_add_sysfs(struct device *cpu_dev) +int cpuidle_add_sysfs(struct cpuidle_device *dev) { - int cpu = cpu_dev->id; - struct cpuidle_device *dev; + struct device *cpu_dev = get_cpu_device((unsigned long)dev->cpu); int error; - dev = per_cpu(cpuidle_devices, cpu); + init_completion(&dev->kobj_unregister); + error = kobject_init_and_add(&dev->kobj, &ktype_cpuidle, &cpu_dev->kobj, "cpuidle"); if (!error) @@ -426,11 +596,8 @@ int cpuidle_add_sysfs(struct device *cpu_dev) * cpuidle_remove_sysfs - deletes a sysfs instance on the target device * @dev: the target device */ -void cpuidle_remove_sysfs(struct device *cpu_dev) +void cpuidle_remove_sysfs(struct cpuidle_device *dev) { - int cpu = cpu_dev->id; - struct cpuidle_device *dev; - - dev = per_cpu(cpuidle_devices, cpu); kobject_put(&dev->kobj); + wait_for_completion(&dev->kobj_unregister); } |