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-rw-r--r--drivers/devfreq/devfreq.c16
-rw-r--r--drivers/devfreq/event/exynos-ppmu.c6
-rw-r--r--drivers/devfreq/rk3399_dmc.c102
-rw-r--r--drivers/powercap/Kconfig10
-rw-r--r--drivers/powercap/Makefile1
-rw-r--r--drivers/powercap/idle_inject.c356
6 files changed, 418 insertions, 73 deletions
diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c
index 0b5b3abe054e..4c49bb1330b5 100644
--- a/drivers/devfreq/devfreq.c
+++ b/drivers/devfreq/devfreq.c
@@ -604,28 +604,29 @@ struct devfreq *devfreq_add_device(struct device *dev,
mutex_lock(&devfreq->lock);
}
- devfreq->min_freq = find_available_min_freq(devfreq);
- if (!devfreq->min_freq) {
+ devfreq->scaling_min_freq = find_available_min_freq(devfreq);
+ if (!devfreq->scaling_min_freq) {
mutex_unlock(&devfreq->lock);
err = -EINVAL;
goto err_dev;
}
- devfreq->scaling_min_freq = devfreq->min_freq;
+ devfreq->min_freq = devfreq->scaling_min_freq;
- devfreq->max_freq = find_available_max_freq(devfreq);
- if (!devfreq->max_freq) {
+ devfreq->scaling_max_freq = find_available_max_freq(devfreq);
+ if (!devfreq->scaling_max_freq) {
mutex_unlock(&devfreq->lock);
err = -EINVAL;
goto err_dev;
}
- devfreq->scaling_max_freq = devfreq->max_freq;
+ devfreq->max_freq = devfreq->scaling_max_freq;
dev_set_name(&devfreq->dev, "devfreq%d",
atomic_inc_return(&devfreq_no));
err = device_register(&devfreq->dev);
if (err) {
mutex_unlock(&devfreq->lock);
- goto err_dev;
+ put_device(&devfreq->dev);
+ goto err_out;
}
devfreq->trans_table =
@@ -672,6 +673,7 @@ err_init:
mutex_unlock(&devfreq_list_lock);
device_unregister(&devfreq->dev);
+ devfreq = NULL;
err_dev:
if (devfreq)
kfree(devfreq);
diff --git a/drivers/devfreq/event/exynos-ppmu.c b/drivers/devfreq/event/exynos-ppmu.c
index 3cd6a184fe7c..a9c64f0d3284 100644
--- a/drivers/devfreq/event/exynos-ppmu.c
+++ b/drivers/devfreq/event/exynos-ppmu.c
@@ -627,11 +627,9 @@ static int exynos_ppmu_probe(struct platform_device *pdev)
size = sizeof(struct devfreq_event_dev *) * info->num_events;
info->edev = devm_kzalloc(&pdev->dev, size, GFP_KERNEL);
- if (!info->edev) {
- dev_err(&pdev->dev,
- "failed to allocate memory devfreq-event devices\n");
+ if (!info->edev)
return -ENOMEM;
- }
+
edev = info->edev;
platform_set_drvdata(pdev, info);
diff --git a/drivers/devfreq/rk3399_dmc.c b/drivers/devfreq/rk3399_dmc.c
index 5dfbfa3cc878..e795ad2b3f6b 100644
--- a/drivers/devfreq/rk3399_dmc.c
+++ b/drivers/devfreq/rk3399_dmc.c
@@ -68,15 +68,6 @@ struct rk3399_dmcfreq {
struct devfreq_event_dev *edev;
struct mutex lock;
struct dram_timing timing;
-
- /*
- * DDR Converser of Frequency (DCF) is used to implement DDR frequency
- * conversion without the participation of CPU, we will implement and
- * control it in arm trust firmware.
- */
- wait_queue_head_t wait_dcf_queue;
- int irq;
- int wait_dcf_flag;
struct regulator *vdd_center;
unsigned long rate, target_rate;
unsigned long volt, target_volt;
@@ -112,31 +103,22 @@ static int rk3399_dmcfreq_target(struct device *dev, unsigned long *freq,
err = regulator_set_voltage(dmcfreq->vdd_center, target_volt,
target_volt);
if (err) {
- dev_err(dev, "Cannot to set voltage %lu uV\n",
+ dev_err(dev, "Cannot set voltage %lu uV\n",
target_volt);
goto out;
}
}
- dmcfreq->wait_dcf_flag = 1;
err = clk_set_rate(dmcfreq->dmc_clk, target_rate);
if (err) {
- dev_err(dev, "Cannot to set frequency %lu (%d)\n",
- target_rate, err);
+ dev_err(dev, "Cannot set frequency %lu (%d)\n", target_rate,
+ err);
regulator_set_voltage(dmcfreq->vdd_center, dmcfreq->volt,
dmcfreq->volt);
goto out;
}
/*
- * Wait until bcf irq happen, it means freq scaling finish in
- * arm trust firmware, use 100ms as timeout time.
- */
- if (!wait_event_timeout(dmcfreq->wait_dcf_queue,
- !dmcfreq->wait_dcf_flag, HZ / 10))
- dev_warn(dev, "Timeout waiting for dcf interrupt\n");
-
- /*
* Check the dpll rate,
* There only two result we will get,
* 1. Ddr frequency scaling fail, we still get the old rate.
@@ -146,8 +128,8 @@ static int rk3399_dmcfreq_target(struct device *dev, unsigned long *freq,
/* If get the incorrect rate, set voltage to old value. */
if (dmcfreq->rate != target_rate) {
- dev_err(dev, "Get wrong ddr frequency, Request frequency %lu,\
- Current frequency %lu\n", target_rate, dmcfreq->rate);
+ dev_err(dev, "Got wrong frequency, Request %lu, Current %lu\n",
+ target_rate, dmcfreq->rate);
regulator_set_voltage(dmcfreq->vdd_center, dmcfreq->volt,
dmcfreq->volt);
goto out;
@@ -155,7 +137,7 @@ static int rk3399_dmcfreq_target(struct device *dev, unsigned long *freq,
err = regulator_set_voltage(dmcfreq->vdd_center, target_volt,
target_volt);
if (err)
- dev_err(dev, "Cannot to set vol %lu uV\n", target_volt);
+ dev_err(dev, "Cannot set voltage %lu uV\n", target_volt);
dmcfreq->rate = target_rate;
dmcfreq->volt = target_volt;
@@ -241,22 +223,6 @@ static __maybe_unused int rk3399_dmcfreq_resume(struct device *dev)
static SIMPLE_DEV_PM_OPS(rk3399_dmcfreq_pm, rk3399_dmcfreq_suspend,
rk3399_dmcfreq_resume);
-static irqreturn_t rk3399_dmc_irq(int irq, void *dev_id)
-{
- struct rk3399_dmcfreq *dmcfreq = dev_id;
- struct arm_smccc_res res;
-
- dmcfreq->wait_dcf_flag = 0;
- wake_up(&dmcfreq->wait_dcf_queue);
-
- /* Clear the DCF interrupt */
- arm_smccc_smc(ROCKCHIP_SIP_DRAM_FREQ, 0, 0,
- ROCKCHIP_SIP_CONFIG_DRAM_CLR_IRQ,
- 0, 0, 0, 0, &res);
-
- return IRQ_HANDLED;
-}
-
static int of_get_ddr_timings(struct dram_timing *timing,
struct device_node *np)
{
@@ -330,16 +296,10 @@ static int rk3399_dmcfreq_probe(struct platform_device *pdev)
struct device *dev = &pdev->dev;
struct device_node *np = pdev->dev.of_node;
struct rk3399_dmcfreq *data;
- int ret, irq, index, size;
+ int ret, index, size;
uint32_t *timing;
struct dev_pm_opp *opp;
- irq = platform_get_irq(pdev, 0);
- if (irq < 0) {
- dev_err(&pdev->dev,
- "Cannot get the dmc interrupt resource: %d\n", irq);
- return irq;
- }
data = devm_kzalloc(dev, sizeof(struct rk3399_dmcfreq), GFP_KERNEL);
if (!data)
return -ENOMEM;
@@ -348,27 +308,22 @@ static int rk3399_dmcfreq_probe(struct platform_device *pdev)
data->vdd_center = devm_regulator_get(dev, "center");
if (IS_ERR(data->vdd_center)) {
+ if (PTR_ERR(data->vdd_center) == -EPROBE_DEFER)
+ return -EPROBE_DEFER;
+
dev_err(dev, "Cannot get the regulator \"center\"\n");
return PTR_ERR(data->vdd_center);
}
data->dmc_clk = devm_clk_get(dev, "dmc_clk");
if (IS_ERR(data->dmc_clk)) {
+ if (PTR_ERR(data->dmc_clk) == -EPROBE_DEFER)
+ return -EPROBE_DEFER;
+
dev_err(dev, "Cannot get the clk dmc_clk\n");
return PTR_ERR(data->dmc_clk);
};
- data->irq = irq;
- ret = devm_request_irq(dev, irq, rk3399_dmc_irq, 0,
- dev_name(dev), data);
- if (ret) {
- dev_err(dev, "Failed to request dmc irq: %d\n", ret);
- return ret;
- }
-
- init_waitqueue_head(&data->wait_dcf_queue);
- data->wait_dcf_flag = 0;
-
data->edev = devfreq_event_get_edev_by_phandle(dev, 0);
if (IS_ERR(data->edev))
return -EPROBE_DEFER;
@@ -420,8 +375,10 @@ static int rk3399_dmcfreq_probe(struct platform_device *pdev)
data->rate = clk_get_rate(data->dmc_clk);
opp = devfreq_recommended_opp(dev, &data->rate, 0);
- if (IS_ERR(opp))
- return PTR_ERR(opp);
+ if (IS_ERR(opp)) {
+ ret = PTR_ERR(opp);
+ goto err_free_opp;
+ }
data->rate = dev_pm_opp_get_freq(opp);
data->volt = dev_pm_opp_get_voltage(opp);
@@ -433,14 +390,34 @@ static int rk3399_dmcfreq_probe(struct platform_device *pdev)
&rk3399_devfreq_dmc_profile,
DEVFREQ_GOV_SIMPLE_ONDEMAND,
&data->ondemand_data);
- if (IS_ERR(data->devfreq))
- return PTR_ERR(data->devfreq);
+ if (IS_ERR(data->devfreq)) {
+ ret = PTR_ERR(data->devfreq);
+ goto err_free_opp;
+ }
+
devm_devfreq_register_opp_notifier(dev, data->devfreq);
data->dev = dev;
platform_set_drvdata(pdev, data);
return 0;
+
+err_free_opp:
+ dev_pm_opp_of_remove_table(&pdev->dev);
+ return ret;
+}
+
+static int rk3399_dmcfreq_remove(struct platform_device *pdev)
+{
+ struct rk3399_dmcfreq *dmcfreq = dev_get_drvdata(&pdev->dev);
+
+ /*
+ * Before remove the opp table we need to unregister the opp notifier.
+ */
+ devm_devfreq_unregister_opp_notifier(dmcfreq->dev, dmcfreq->devfreq);
+ dev_pm_opp_of_remove_table(dmcfreq->dev);
+
+ return 0;
}
static const struct of_device_id rk3399dmc_devfreq_of_match[] = {
@@ -451,6 +428,7 @@ MODULE_DEVICE_TABLE(of, rk3399dmc_devfreq_of_match);
static struct platform_driver rk3399_dmcfreq_driver = {
.probe = rk3399_dmcfreq_probe,
+ .remove = rk3399_dmcfreq_remove,
.driver = {
.name = "rk3399-dmc-freq",
.pm = &rk3399_dmcfreq_pm,
diff --git a/drivers/powercap/Kconfig b/drivers/powercap/Kconfig
index 85727ef6ce8e..6ac27e5908f5 100644
--- a/drivers/powercap/Kconfig
+++ b/drivers/powercap/Kconfig
@@ -29,4 +29,14 @@ config INTEL_RAPL
controller, CPU core (Power Plance 0), graphics uncore (Power Plane
1), etc.
+config IDLE_INJECT
+ bool "Idle injection framework"
+ depends on CPU_IDLE
+ default n
+ help
+ This enables support for the idle injection framework. It
+ provides a way to force idle periods on a set of specified
+ CPUs for power capping. Idle period can be injected
+ synchronously on a set of specified CPUs or alternatively
+ on a per CPU basis.
endif
diff --git a/drivers/powercap/Makefile b/drivers/powercap/Makefile
index 0a21ef31372b..1b328854b36e 100644
--- a/drivers/powercap/Makefile
+++ b/drivers/powercap/Makefile
@@ -1,2 +1,3 @@
obj-$(CONFIG_POWERCAP) += powercap_sys.o
obj-$(CONFIG_INTEL_RAPL) += intel_rapl.o
+obj-$(CONFIG_IDLE_INJECT) += idle_inject.o
diff --git a/drivers/powercap/idle_inject.c b/drivers/powercap/idle_inject.c
new file mode 100644
index 000000000000..24ff2a068978
--- /dev/null
+++ b/drivers/powercap/idle_inject.c
@@ -0,0 +1,356 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright 2018 Linaro Limited
+ *
+ * Author: Daniel Lezcano <daniel.lezcano@linaro.org>
+ *
+ * The idle injection framework provides a way to force CPUs to enter idle
+ * states for a specified fraction of time over a specified period.
+ *
+ * It relies on the smpboot kthreads feature providing common code for CPU
+ * hotplug and thread [un]parking.
+ *
+ * All of the kthreads used for idle injection are created at init time.
+ *
+ * Next, the users of the the idle injection framework provide a cpumask via
+ * its register function. The kthreads will be synchronized with respect to
+ * this cpumask.
+ *
+ * The idle + run duration is specified via separate helpers and that allows
+ * idle injection to be started.
+ *
+ * The idle injection kthreads will call play_idle() with the idle duration
+ * specified as per the above.
+ *
+ * After all of them have been woken up, a timer is set to start the next idle
+ * injection cycle.
+ *
+ * The timer interrupt handler will wake up the idle injection kthreads for
+ * all of the CPUs in the cpumask provided by the user.
+ *
+ * Idle injection is stopped synchronously and no leftover idle injection
+ * kthread activity after its completion is guaranteed.
+ *
+ * It is up to the user of this framework to provide a lock for higher-level
+ * synchronization to prevent race conditions like starting idle injection
+ * while unregistering from the framework.
+ */
+#define pr_fmt(fmt) "ii_dev: " fmt
+
+#include <linux/cpu.h>
+#include <linux/hrtimer.h>
+#include <linux/kthread.h>
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include <linux/smpboot.h>
+
+#include <uapi/linux/sched/types.h>
+
+/**
+ * struct idle_inject_thread - task on/off switch structure
+ * @tsk: task injecting the idle cycles
+ * @should_run: whether or not to run the task (for the smpboot kthread API)
+ */
+struct idle_inject_thread {
+ struct task_struct *tsk;
+ int should_run;
+};
+
+/**
+ * struct idle_inject_device - idle injection data
+ * @timer: idle injection period timer
+ * @idle_duration_ms: duration of CPU idle time to inject
+ * @run_duration_ms: duration of CPU run time to allow
+ * @cpumask: mask of CPUs affected by idle injection
+ */
+struct idle_inject_device {
+ struct hrtimer timer;
+ unsigned int idle_duration_ms;
+ unsigned int run_duration_ms;
+ unsigned long int cpumask[0];
+};
+
+static DEFINE_PER_CPU(struct idle_inject_thread, idle_inject_thread);
+static DEFINE_PER_CPU(struct idle_inject_device *, idle_inject_device);
+
+/**
+ * idle_inject_wakeup - Wake up idle injection threads
+ * @ii_dev: target idle injection device
+ *
+ * Every idle injection task associated with the given idle injection device
+ * and running on an online CPU will be woken up.
+ */
+static void idle_inject_wakeup(struct idle_inject_device *ii_dev)
+{
+ struct idle_inject_thread *iit;
+ unsigned int cpu;
+
+ for_each_cpu_and(cpu, to_cpumask(ii_dev->cpumask), cpu_online_mask) {
+ iit = per_cpu_ptr(&idle_inject_thread, cpu);
+ iit->should_run = 1;
+ wake_up_process(iit->tsk);
+ }
+}
+
+/**
+ * idle_inject_timer_fn - idle injection timer function
+ * @timer: idle injection hrtimer
+ *
+ * This function is called when the idle injection timer expires. It wakes up
+ * idle injection tasks associated with the timer and they, in turn, invoke
+ * play_idle() to inject a specified amount of CPU idle time.
+ *
+ * Return: HRTIMER_RESTART.
+ */
+static enum hrtimer_restart idle_inject_timer_fn(struct hrtimer *timer)
+{
+ unsigned int duration_ms;
+ struct idle_inject_device *ii_dev =
+ container_of(timer, struct idle_inject_device, timer);
+
+ duration_ms = READ_ONCE(ii_dev->run_duration_ms);
+ duration_ms += READ_ONCE(ii_dev->idle_duration_ms);
+
+ idle_inject_wakeup(ii_dev);
+
+ hrtimer_forward_now(timer, ms_to_ktime(duration_ms));
+
+ return HRTIMER_RESTART;
+}
+
+/**
+ * idle_inject_fn - idle injection work function
+ * @cpu: the CPU owning the task
+ *
+ * This function calls play_idle() to inject a specified amount of CPU idle
+ * time.
+ */
+static void idle_inject_fn(unsigned int cpu)
+{
+ struct idle_inject_device *ii_dev;
+ struct idle_inject_thread *iit;
+
+ ii_dev = per_cpu(idle_inject_device, cpu);
+ iit = per_cpu_ptr(&idle_inject_thread, cpu);
+
+ /*
+ * Let the smpboot main loop know that the task should not run again.
+ */
+ iit->should_run = 0;
+
+ play_idle(READ_ONCE(ii_dev->idle_duration_ms));
+}
+
+/**
+ * idle_inject_set_duration - idle and run duration update helper
+ * @run_duration_ms: CPU run time to allow in milliseconds
+ * @idle_duration_ms: CPU idle time to inject in milliseconds
+ */
+void idle_inject_set_duration(struct idle_inject_device *ii_dev,
+ unsigned int run_duration_ms,
+ unsigned int idle_duration_ms)
+{
+ if (run_duration_ms && idle_duration_ms) {
+ WRITE_ONCE(ii_dev->run_duration_ms, run_duration_ms);
+ WRITE_ONCE(ii_dev->idle_duration_ms, idle_duration_ms);
+ }
+}
+
+/**
+ * idle_inject_get_duration - idle and run duration retrieval helper
+ * @run_duration_ms: memory location to store the current CPU run time
+ * @idle_duration_ms: memory location to store the current CPU idle time
+ */
+void idle_inject_get_duration(struct idle_inject_device *ii_dev,
+ unsigned int *run_duration_ms,
+ unsigned int *idle_duration_ms)
+{
+ *run_duration_ms = READ_ONCE(ii_dev->run_duration_ms);
+ *idle_duration_ms = READ_ONCE(ii_dev->idle_duration_ms);
+}
+
+/**
+ * idle_inject_start - start idle injections
+ * @ii_dev: idle injection control device structure
+ *
+ * The function starts idle injection by first waking up all of the idle
+ * injection kthreads associated with @ii_dev to let them inject CPU idle time
+ * sets up a timer to start the next idle injection period.
+ *
+ * Return: -EINVAL if the CPU idle or CPU run time is not set or 0 on success.
+ */
+int idle_inject_start(struct idle_inject_device *ii_dev)
+{
+ unsigned int idle_duration_ms = READ_ONCE(ii_dev->idle_duration_ms);
+ unsigned int run_duration_ms = READ_ONCE(ii_dev->run_duration_ms);
+
+ if (!idle_duration_ms || !run_duration_ms)
+ return -EINVAL;
+
+ pr_debug("Starting injecting idle cycles on CPUs '%*pbl'\n",
+ cpumask_pr_args(to_cpumask(ii_dev->cpumask)));
+
+ idle_inject_wakeup(ii_dev);
+
+ hrtimer_start(&ii_dev->timer,
+ ms_to_ktime(idle_duration_ms + run_duration_ms),
+ HRTIMER_MODE_REL);
+
+ return 0;
+}
+
+/**
+ * idle_inject_stop - stops idle injections
+ * @ii_dev: idle injection control device structure
+ *
+ * The function stops idle injection and waits for the threads to finish work.
+ * If CPU idle time is being injected when this function runs, then it will
+ * wait until the end of the cycle.
+ *
+ * When it returns, there is no more idle injection kthread activity. The
+ * kthreads are scheduled out and the periodic timer is off.
+ */
+void idle_inject_stop(struct idle_inject_device *ii_dev)
+{
+ struct idle_inject_thread *iit;
+ unsigned int cpu;
+
+ pr_debug("Stopping idle injection on CPUs '%*pbl'\n",
+ cpumask_pr_args(to_cpumask(ii_dev->cpumask)));
+
+ hrtimer_cancel(&ii_dev->timer);
+
+ /*
+ * Stopping idle injection requires all of the idle injection kthreads
+ * associated with the given cpumask to be parked and stay that way, so
+ * prevent CPUs from going online at this point. Any CPUs going online
+ * after the loop below will be covered by clearing the should_run flag
+ * that will cause the smpboot main loop to schedule them out.
+ */
+ cpu_hotplug_disable();
+
+ /*
+ * Iterate over all (online + offline) CPUs here in case one of them
+ * goes offline with the should_run flag set so as to prevent its idle
+ * injection kthread from running when the CPU goes online again after
+ * the ii_dev has been freed.
+ */
+ for_each_cpu(cpu, to_cpumask(ii_dev->cpumask)) {
+ iit = per_cpu_ptr(&idle_inject_thread, cpu);
+ iit->should_run = 0;
+
+ wait_task_inactive(iit->tsk, 0);
+ }
+
+ cpu_hotplug_enable();
+}
+
+/**
+ * idle_inject_setup - prepare the current task for idle injection
+ * @cpu: not used
+ *
+ * Called once, this function is in charge of setting the current task's
+ * scheduler parameters to make it an RT task.
+ */
+static void idle_inject_setup(unsigned int cpu)
+{
+ struct sched_param param = { .sched_priority = MAX_USER_RT_PRIO / 2 };
+
+ sched_setscheduler(current, SCHED_FIFO, &param);
+}
+
+/**
+ * idle_inject_should_run - function helper for the smpboot API
+ * @cpu: CPU the kthread is running on
+ *
+ * Return: whether or not the thread can run.
+ */
+static int idle_inject_should_run(unsigned int cpu)
+{
+ struct idle_inject_thread *iit =
+ per_cpu_ptr(&idle_inject_thread, cpu);
+
+ return iit->should_run;
+}
+
+/**
+ * idle_inject_register - initialize idle injection on a set of CPUs
+ * @cpumask: CPUs to be affected by idle injection
+ *
+ * This function creates an idle injection control device structure for the
+ * given set of CPUs and initializes the timer associated with it. It does not
+ * start any injection cycles.
+ *
+ * Return: NULL if memory allocation fails, idle injection control device
+ * pointer on success.
+ */
+struct idle_inject_device *idle_inject_register(struct cpumask *cpumask)
+{
+ struct idle_inject_device *ii_dev;
+ int cpu, cpu_rb;
+
+ ii_dev = kzalloc(sizeof(*ii_dev) + cpumask_size(), GFP_KERNEL);
+ if (!ii_dev)
+ return NULL;
+
+ cpumask_copy(to_cpumask(ii_dev->cpumask), cpumask);
+ hrtimer_init(&ii_dev->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
+ ii_dev->timer.function = idle_inject_timer_fn;
+
+ for_each_cpu(cpu, to_cpumask(ii_dev->cpumask)) {
+
+ if (per_cpu(idle_inject_device, cpu)) {
+ pr_err("cpu%d is already registered\n", cpu);
+ goto out_rollback;
+ }
+
+ per_cpu(idle_inject_device, cpu) = ii_dev;
+ }
+
+ return ii_dev;
+
+out_rollback:
+ for_each_cpu(cpu_rb, to_cpumask(ii_dev->cpumask)) {
+ if (cpu == cpu_rb)
+ break;
+ per_cpu(idle_inject_device, cpu_rb) = NULL;
+ }
+
+ kfree(ii_dev);
+
+ return NULL;
+}
+
+/**
+ * idle_inject_unregister - unregister idle injection control device
+ * @ii_dev: idle injection control device to unregister
+ *
+ * The function stops idle injection for the given control device,
+ * unregisters its kthreads and frees memory allocated when that device was
+ * created.
+ */
+void idle_inject_unregister(struct idle_inject_device *ii_dev)
+{
+ unsigned int cpu;
+
+ idle_inject_stop(ii_dev);
+
+ for_each_cpu(cpu, to_cpumask(ii_dev->cpumask))
+ per_cpu(idle_inject_device, cpu) = NULL;
+
+ kfree(ii_dev);
+}
+
+static struct smp_hotplug_thread idle_inject_threads = {
+ .store = &idle_inject_thread.tsk,
+ .setup = idle_inject_setup,
+ .thread_fn = idle_inject_fn,
+ .thread_comm = "idle_inject/%u",
+ .thread_should_run = idle_inject_should_run,
+};
+
+static int __init idle_inject_init(void)
+{
+ return smpboot_register_percpu_thread(&idle_inject_threads);
+}
+early_initcall(idle_inject_init);