devfreq expects governors to call devfreq_monitor_start/stop() in response to DEVFREQ_GOV_START/STOP events. Since the devfreq core itself generates these events and invokes the governor's event handler the start/stop of the load monitor can be done in the common code.
Call devfreq_monitor_start/stop() when the governor reports a successful handling of DEVFREQ_GOV_START/STOP and remove these calls from the simpleondemand and tegra governors. Make devfreq_monitor_start/stop() static since these functions are now only used by the devfreq core. For better integration with the callers the functions must now be called with devfreq->lock held. Also stop manipulating the monitor workqueue directly, use devfreq_monitor_start/stop() instead. Signed-off-by: Matthias Kaehlcke <[email protected]> --- drivers/devfreq/devfreq.c | 45 +++++++++++------------ drivers/devfreq/governor.h | 2 - drivers/devfreq/governor_simpleondemand.c | 8 ---- drivers/devfreq/tegra-devfreq.c | 2 - 4 files changed, 22 insertions(+), 35 deletions(-) diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c index eb86461648d74..ac553c00f6790 100644 --- a/drivers/devfreq/devfreq.c +++ b/drivers/devfreq/devfreq.c @@ -404,14 +404,14 @@ static void devfreq_monitor(struct work_struct *work) * devfreq_monitor_start() - Start load monitoring of devfreq instance * @devfreq: the devfreq instance. * - * Helper function for starting devfreq device load monitoing. By - * default delayed work based monitoring is supported. Function - * to be called from governor in response to DEVFREQ_GOV_START - * event when device is added to devfreq framework. + * Helper function for starting devfreq device load monitoring. By + * default delayed work based monitoring is supported. Must be called + * with devfreq->lock held. */ -void devfreq_monitor_start(struct devfreq *devfreq) +static void devfreq_monitor_start(struct devfreq *devfreq) { - mutex_lock(&devfreq->lock); + WARN(!mutex_is_locked(&devfreq->lock), + "devfreq->lock must be held by the caller.\n"); if (devfreq->profile->polling_ms) { INIT_DEFERRABLE_WORK(&devfreq->work, devfreq_monitor); @@ -420,28 +420,28 @@ void devfreq_monitor_start(struct devfreq *devfreq) devfreq->monitor_state = DEVFREQ_MONITOR_RUNNING; } - - mutex_unlock(&devfreq->lock); } -EXPORT_SYMBOL(devfreq_monitor_start); /** * devfreq_monitor_stop() - Stop load monitoring of a devfreq instance * @devfreq: the devfreq instance. * - * Helper function to stop devfreq device load monitoing. Function - * to be called from governor in response to DEVFREQ_GOV_STOP - * event when device is removed from devfreq framework. + * Helper function to stop devfreq device load monitoring. Must be + * called with devfreq->lock held. */ -void devfreq_monitor_stop(struct devfreq *devfreq) +static void devfreq_monitor_stop(struct devfreq *devfreq) { + /* mutex must be held for symmetry with _start() */ + WARN(!mutex_is_locked(&devfreq->lock), + "devfreq->lock must be held by the caller.\n"); + + mutex_unlock(&devfreq->lock); cancel_delayed_work_sync(&devfreq->work); mutex_lock(&devfreq->lock); devfreq->monitor_state = DEVFREQ_MONITOR_STOPPED; mutex_unlock(&devfreq->lock); } -EXPORT_SYMBOL(devfreq_monitor_stop); /** * devfreq_monitor_suspend() - Suspend load monitoring of a devfreq instance @@ -518,27 +518,22 @@ void devfreq_interval_update(struct devfreq *devfreq, unsigned int *delay) /* if new delay is zero, stop polling */ if (!new_delay) { + devfreq_monitor_stop(devfreq); mutex_unlock(&devfreq->lock); - cancel_delayed_work_sync(&devfreq->work); - devfreq->monitor_state == DEVFREQ_MONITOR_STOPPED; return; } /* if current delay is zero, start polling with new delay */ if (!cur_delay) { - queue_delayed_work(devfreq_wq, &devfreq->work, - msecs_to_jiffies(devfreq->profile->polling_ms)); + devfreq_monitor_start(devfreq); goto out; } /* if current delay is greater than new delay, restart polling */ if (cur_delay > new_delay) { - mutex_unlock(&devfreq->lock); - cancel_delayed_work_sync(&devfreq->work); - mutex_lock(&devfreq->lock); + devfreq_monitor_stop(devfreq); if (devfreq->monitor_state != DEVFREQ_MONITOR_SUSPENDED) - queue_delayed_work(devfreq_wq, &devfreq->work, - msecs_to_jiffies(devfreq->profile->polling_ms)); + devfreq_monitor_start(devfreq); } out: mutex_unlock(&devfreq->lock); @@ -601,6 +596,8 @@ static int devfreq_governor_start(struct devfreq *devfreq) return err; } + devfreq_monitor_start(devfreq); + return 0; } @@ -624,6 +621,8 @@ static int devfreq_governor_stop(struct devfreq *devfreq) return err; } + devfreq_monitor_stop(devfreq); + return 0; } diff --git a/drivers/devfreq/governor.h b/drivers/devfreq/governor.h index d136792c0cc91..47efe747b6f79 100644 --- a/drivers/devfreq/governor.h +++ b/drivers/devfreq/governor.h @@ -57,8 +57,6 @@ struct devfreq_governor { unsigned int event, void *data); }; -extern void devfreq_monitor_start(struct devfreq *devfreq); -extern void devfreq_monitor_stop(struct devfreq *devfreq); extern void devfreq_interval_update(struct devfreq *devfreq, unsigned int *delay); diff --git a/drivers/devfreq/governor_simpleondemand.c b/drivers/devfreq/governor_simpleondemand.c index 52eb0c734b312..e0f0944a9c7aa 100644 --- a/drivers/devfreq/governor_simpleondemand.c +++ b/drivers/devfreq/governor_simpleondemand.c @@ -91,14 +91,6 @@ static int devfreq_simple_ondemand_handler(struct devfreq *devfreq, unsigned int event, void *data) { switch (event) { - case DEVFREQ_GOV_START: - devfreq_monitor_start(devfreq); - break; - - case DEVFREQ_GOV_STOP: - devfreq_monitor_stop(devfreq); - break; - case DEVFREQ_GOV_INTERVAL: devfreq_interval_update(devfreq, (unsigned int *)data); break; diff --git a/drivers/devfreq/tegra-devfreq.c b/drivers/devfreq/tegra-devfreq.c index 79efa1e51bd06..515fb852dbad6 100644 --- a/drivers/devfreq/tegra-devfreq.c +++ b/drivers/devfreq/tegra-devfreq.c @@ -580,13 +580,11 @@ static int tegra_governor_event_handler(struct devfreq *devfreq, switch (event) { case DEVFREQ_GOV_START: - devfreq_monitor_start(devfreq); tegra_actmon_enable_interrupts(tegra); break; case DEVFREQ_GOV_STOP: tegra_actmon_disable_interrupts(tegra); - devfreq_monitor_stop(devfreq); break; case DEVFREQ_GOV_SUSPEND: -- 2.20.1.791.gb4d0f1c61a-goog
