Hi,
On 19. 9. 20. 오전 2:44, Matthias Kaehlcke wrote:
> Add a tracepoint for frequency changes of devfreq devices and
> use it.
>
> Signed-off-by: Matthias Kaehlcke <m...@chromium.org>
> ---
> (sending v2 without much delay wrt v1, since the change in devfreq
> probably isn't controversial, and I'll be offline a few days)
>
> Changes in v2:
> - included trace_devfreq_frequency_enabled() in the condition
> to avoid unnecessary evaluation when the trace point is
> disabled
> ---
> drivers/devfreq/devfreq.c | 3 +++
> include/trace/events/devfreq.h | 18 ++++++++++++++++++
> 2 files changed, 21 insertions(+)
>
> diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c
> index ab22bf8a12d6..e9f04dcafb01 100644
> --- a/drivers/devfreq/devfreq.c
> +++ b/drivers/devfreq/devfreq.c
> @@ -317,6 +317,9 @@ static int devfreq_set_target(struct devfreq *devfreq,
> unsigned long new_freq,
>
> devfreq->previous_freq = new_freq;
>
> + if (trace_devfreq_frequency_enabled() && new_freq != cur_freq)
> + trace_devfreq_frequency(devfreq, new_freq);
You can change as following without 'new_freq' variable
because devfreq->previous_freq is the new frequency.
trace_devfreq_frequency(devfreq);
> +
> if (devfreq->suspend_freq)
> devfreq->resume_freq = cur_freq;
>
> diff --git a/include/trace/events/devfreq.h b/include/trace/events/devfreq.h
> index cf5b8772175d..a62d32fe3c33 100644
> --- a/include/trace/events/devfreq.h
> +++ b/include/trace/events/devfreq.h
> @@ -8,6 +8,24 @@
> #include <linux/devfreq.h>
> #include <linux/tracepoint.h>
>
> +TRACE_EVENT(devfreq_frequency,
> + TP_PROTO(struct devfreq *devfreq, unsigned long freq),
'unsigned long freq' parameter is not necessary.
> +
> + TP_ARGS(devfreq, freq),
> +
> + TP_STRUCT__entry(
> + __string(dev_name, dev_name(&devfreq->dev))
> + __field(unsigned long, freq)
> + ),
> +
> + TP_fast_assign(
> + __assign_str(dev_name, dev_name(&devfreq->dev));
> + __entry->freq = freq;
Initialize the new frequency with 'devfreq->previous_freq' as following:
__entry->freq = devfreq->previous_freq;
> + ),
> +
> + TP_printk("dev_name=%s freq=%lu", __get_str(dev_name), __entry->freq)
> +);
> +
> TRACE_EVENT(devfreq_monitor,
> TP_PROTO(struct devfreq *devfreq),
>
>
--
Best Regards,
Chanwoo Choi
Samsung Electronics
