Messages in this thread | | | From | Dong Aisheng <> | Date | Wed, 10 Mar 2021 10:56:18 +0800 | Subject | Re: [PATCH 07/11] PM / devfreq: check get_dev_status before start monitor |
| |
On Wed, Mar 10, 2021 at 12:12 AM Chanwoo Choi <cwchoi00@gmail.com> wrote: > > On 21. 3. 10. 오전 12:58, Chanwoo Choi wrote: > > On 21. 3. 9. 오후 9:58, Dong Aisheng wrote: > >> The devfreq monitor depends on the device to provide load information > >> by .get_dev_status() to calculate the next target freq. > >> > >> And this will cause changing governor to simple ondemand fail > >> if device can't support. > >> > >> Signed-off-by: Dong Aisheng <aisheng.dong@nxp.com> > >> --- > >> drivers/devfreq/devfreq.c | 10 +++++++--- > >> drivers/devfreq/governor.h | 2 +- > >> drivers/devfreq/governor_simpleondemand.c | 3 +-- > >> 3 files changed, 9 insertions(+), 6 deletions(-) > >> > >> diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c > >> index 7231fe6862a2..d1787b6c7d7c 100644 > >> --- a/drivers/devfreq/devfreq.c > >> +++ b/drivers/devfreq/devfreq.c > >> @@ -482,10 +482,13 @@ static void devfreq_monitor(struct work_struct > >> *work) > >> * to be called from governor in response to DEVFREQ_GOV_START > >> * event when device is added to devfreq framework. > >> */ > >> -void devfreq_monitor_start(struct devfreq *devfreq) > >> +int devfreq_monitor_start(struct devfreq *devfreq) > >> { > >> if (IS_SUPPORTED_FLAG(devfreq->governor->flags, IRQ_DRIVEN)) > >> - return; > >> + return 0; > >> + > >> + if (!devfreq->profile->get_dev_status) > >> + return -EINVAL; > > Again, I think that get_dev_status is not used for all governors. > So that it cause the governor start fail. Don't check whether > .get_dev_status is NULL or not. >
I'm not quite understand your point. it is used by governor_simpleondemand.c and tegra_devfreq_governor. get_target_freq -> devfreq_update_stats -> get_dev_status
Without checking, device can switch to ondemand governor if it does not support.
Am i missed something?
Regards Aisheng
> >> switch (devfreq->profile->timer) { > >> case DEVFREQ_TIMER_DEFERRABLE: > >> @@ -495,12 +498,13 @@ void devfreq_monitor_start(struct devfreq *devfreq) > >> INIT_DELAYED_WORK(&devfreq->work, devfreq_monitor); > >> break; > >> default: > >> - return; > >> + return -EINVAL; > >> } > >> if (devfreq->profile->polling_ms) > >> queue_delayed_work(devfreq_wq, &devfreq->work, > >> msecs_to_jiffies(devfreq->profile->polling_ms)); > >> + return 0; > >> } > >> EXPORT_SYMBOL(devfreq_monitor_start); > >> diff --git a/drivers/devfreq/governor.h b/drivers/devfreq/governor.h > >> index 5cee3f64fe2b..31af6d072a10 100644 > >> --- a/drivers/devfreq/governor.h > >> +++ b/drivers/devfreq/governor.h > >> @@ -75,7 +75,7 @@ struct devfreq_governor { > >> unsigned int event, void *data); > >> }; > >> -void devfreq_monitor_start(struct devfreq *devfreq); > >> +int devfreq_monitor_start(struct devfreq *devfreq); > >> void devfreq_monitor_stop(struct devfreq *devfreq); > >> void devfreq_monitor_suspend(struct devfreq *devfreq); > >> void devfreq_monitor_resume(struct devfreq *devfreq); > >> diff --git a/drivers/devfreq/governor_simpleondemand.c > >> b/drivers/devfreq/governor_simpleondemand.c > >> index d57b82a2b570..ea287b57cbf3 100644 > >> --- a/drivers/devfreq/governor_simpleondemand.c > >> +++ b/drivers/devfreq/governor_simpleondemand.c > >> @@ -89,8 +89,7 @@ static int devfreq_simple_ondemand_handler(struct > >> devfreq *devfreq, > >> { > >> switch (event) { > >> case DEVFREQ_GOV_START: > >> - devfreq_monitor_start(devfreq); > >> - break; > >> + return devfreq_monitor_start(devfreq); > >> case DEVFREQ_GOV_STOP: > >> devfreq_monitor_stop(devfreq); > >> > > > > Need to handle the all points of devfreq_monitor_start() usage. > > please check the tegra30-devfreq.c for this update. > > > > $ grep -rn "devfreq_monitor_start" drivers/ > > drivers/devfreq/governor_simpleondemand.c:92: > > devfreq_monitor_start(devfreq); > > drivers/devfreq/tegra30-devfreq.c:744: > > devfreq_monitor_start(devfreq); > > ...... > > > > > -- > Best Regards, > Samsung Electronics > Chanwoo Choi
| |