diff options
Diffstat (limited to 'drivers/powercap')
| -rw-r--r-- | drivers/powercap/idle_inject.c | 52 |
1 files changed, 46 insertions, 6 deletions
diff --git a/drivers/powercap/idle_inject.c b/drivers/powercap/idle_inject.c index dfa989182e71..6862e6c2e87d 100644 --- a/drivers/powercap/idle_inject.c +++ b/drivers/powercap/idle_inject.c @@ -63,13 +63,29 @@ struct idle_inject_thread { * @idle_duration_us: duration of CPU idle time to inject * @run_duration_us: duration of CPU run time to allow * @latency_us: max allowed latency + * @update: Optional callback deciding whether or not to skip idle + * injection in the given cycle. * @cpumask: mask of CPUs affected by idle injection + * + * This structure is used to define per instance idle inject device data. Each + * instance has an idle duration, a run duration and mask of CPUs to inject + * idle. + * + * Actual CPU idle time is injected by calling kernel scheduler interface + * play_idle_precise(). There is one optional callback that can be registered + * by calling idle_inject_register_full(): + * + * update() - This callback is invoked just before waking up CPUs to inject + * idle. If it returns false, CPUs are not woken up to inject idle in the given + * cycle. It also allows the caller to readjust the idle and run duration by + * calling idle_inject_set_duration() for the next cycle. */ struct idle_inject_device { struct hrtimer timer; unsigned int idle_duration_us; unsigned int run_duration_us; unsigned int latency_us; + bool (*update)(void); unsigned long cpumask[]; }; @@ -111,11 +127,12 @@ static enum hrtimer_restart idle_inject_timer_fn(struct hrtimer *timer) struct idle_inject_device *ii_dev = container_of(timer, struct idle_inject_device, timer); + if (!ii_dev->update || (ii_dev->update && ii_dev->update())) + idle_inject_wakeup(ii_dev); + duration_us = READ_ONCE(ii_dev->run_duration_us); duration_us += READ_ONCE(ii_dev->idle_duration_us); - idle_inject_wakeup(ii_dev); - hrtimer_forward_now(timer, ns_to_ktime(duration_us * NSEC_PER_USEC)); return HRTIMER_RESTART; @@ -295,17 +312,22 @@ static int idle_inject_should_run(unsigned int cpu) } /** - * idle_inject_register - initialize idle injection on a set of CPUs + * idle_inject_register_full - initialize idle injection on a set of CPUs * @cpumask: CPUs to be affected by idle injection + * @update: This callback is called just before waking up CPUs to inject + * idle * * 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. + * given set of CPUs and initializes the timer associated with it. This + * function also allows to register update()callback. + * 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 *idle_inject_register_full(struct cpumask *cpumask, + bool (*update)(void)) { struct idle_inject_device *ii_dev; int cpu, cpu_rb; @@ -318,6 +340,7 @@ struct idle_inject_device *idle_inject_register(struct cpumask *cpumask) hrtimer_init(&ii_dev->timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL); ii_dev->timer.function = idle_inject_timer_fn; ii_dev->latency_us = UINT_MAX; + ii_dev->update = update; for_each_cpu(cpu, to_cpumask(ii_dev->cpumask)) { @@ -342,6 +365,23 @@ out_rollback: return NULL; } +EXPORT_SYMBOL_NS_GPL(idle_inject_register_full, IDLE_INJECT); + +/** + * 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) +{ + return idle_inject_register_full(cpumask, NULL); +} EXPORT_SYMBOL_NS_GPL(idle_inject_register, IDLE_INJECT); /** |