Re: [PATCH v4] PM / devfreq: Move statistics to separate struct devfreq_stats

[Chanwoo Choi]

On 12/6/19 2:33 PM, Chanwoo Choi wrote:
> From: Kamil Konieczny <k.konieczny@xxxxxxxxxxx>
> 
> Count time and transitions between devfreq frequencies in separate
> struct devfreq_stats for improved code readability and maintenance.
> 
> Signed-off-by: Kamil Konieczny <k.konieczny@xxxxxxxxxxx>
> Reviewed-by: Matthias Kaehlcke <mka@xxxxxxxxxxxx>
> [cw00.choi: Fix the merge conflict in trasn_stat_store]
> Signed-off-by: Chanwoo Choi <cw00.choi@xxxxxxxxxxx>
> ---
>  drivers/devfreq/devfreq.c | 44 ++++++++++++++++++++-------------------
>  include/linux/devfreq.h   | 26 +++++++++++++++--------
>  2 files changed, 40 insertions(+), 30 deletions(-)
> 
> diff --git a/drivers/devfreq/devfreq.c b/drivers/devfreq/devfreq.c
> index df31f430051d..1786a86b1779 100644
> --- a/drivers/devfreq/devfreq.c
> +++ b/drivers/devfreq/devfreq.c
> @@ -214,8 +214,8 @@ int devfreq_update_status(struct devfreq *devfreq, unsigned long freq)
>  		goto out;
>  	}
>  
> -	devfreq->time_in_state[prev_lev] +=
> -			 cur_time - devfreq->last_stat_updated;
> +	devfreq->stats.time_in_state[prev_lev] +=
> +			cur_time - devfreq->stats.last_update;
>  
>  	lev = devfreq_get_freq_level(devfreq, freq);
>  	if (lev < 0) {
> @@ -224,13 +224,13 @@ int devfreq_update_status(struct devfreq *devfreq, unsigned long freq)
>  	}
>  
>  	if (lev != prev_lev) {
> -		devfreq->trans_table[(prev_lev *
> -				devfreq->profile->max_state) + lev]++;
> -		devfreq->total_trans++;
> +		devfreq->stats.trans_table[
> +			(prev_lev * devfreq->profile->max_state) + lev]++;
> +		devfreq->stats.total_trans++;
>  	}
>  
>  out:
> -	devfreq->last_stat_updated = cur_time;
> +	devfreq->stats.last_update = cur_time;
>  	return ret;
>  }
>  EXPORT_SYMBOL(devfreq_update_status);
> @@ -525,7 +525,7 @@ void devfreq_monitor_resume(struct devfreq *devfreq)
>  			msecs_to_jiffies(devfreq->profile->polling_ms));
>  
>  out_update:
> -	devfreq->last_stat_updated = get_jiffies_64();
> +	devfreq->stats.last_update = get_jiffies_64();
>  	devfreq->stop_polling = false;
>  
>  	if (devfreq->profile->get_cur_freq &&
> @@ -735,28 +735,29 @@ struct devfreq *devfreq_add_device(struct device *dev,
>  		goto err_out;
>  	}
>  
> -	devfreq->trans_table = devm_kzalloc(&devfreq->dev,
> +	devfreq->stats.trans_table = devm_kzalloc(&devfreq->dev,
>  			array3_size(sizeof(unsigned int),
>  				    devfreq->profile->max_state,
>  				    devfreq->profile->max_state),
>  			GFP_KERNEL);
> -	if (!devfreq->trans_table) {
> +	if (!devfreq->stats.trans_table) {
>  		mutex_unlock(&devfreq->lock);
>  		err = -ENOMEM;
>  		goto err_devfreq;
>  	}
>  
> -	devfreq->time_in_state = devm_kcalloc(&devfreq->dev,
> +	devfreq->stats.time_in_state = devm_kcalloc(&devfreq->dev,
>  			devfreq->profile->max_state,
> -			sizeof(*devfreq->time_in_state),
> +			sizeof(*devfreq->stats.time_in_state),
>  			GFP_KERNEL);
> -	if (!devfreq->time_in_state) {
> +	if (!devfreq->stats.time_in_state) {
>  		mutex_unlock(&devfreq->lock);
>  		err = -ENOMEM;
>  		goto err_devfreq;
>  	}
>  
> -	devfreq->last_stat_updated = get_jiffies_64();
> +	devfreq->stats.total_trans = 0;
> +	devfreq->stats.last_update = get_jiffies_64();
>  
>  	srcu_init_notifier_head(&devfreq->transition_notifier_list);
>  
> @@ -1469,13 +1470,14 @@ static ssize_t trans_stat_show(struct device *dev,
>  				devfreq->profile->freq_table[i]);
>  		for (j = 0; j < max_state; j++)
>  			len += sprintf(buf + len, "%10u",
> -				devfreq->trans_table[(i * max_state) + j]);
> +				devfreq->stats.trans_table[(i * max_state) + j]);
> +
>  		len += sprintf(buf + len, "%10llu\n", (u64)
> -			jiffies64_to_msecs(devfreq->time_in_state[i]));
> +			jiffies64_to_msecs(devfreq->stats.time_in_state[i]));
>  	}
>  
>  	len += sprintf(buf + len, "Total transition : %u\n",
> -					devfreq->total_trans);
> +					devfreq->stats.total_trans);
>  	return len;
>  }
>  
> @@ -1494,13 +1496,13 @@ static ssize_t trans_stat_store(struct device *dev,
>  		return -EINVAL;
>  
>  	mutex_lock(&df->lock);
> -	memset(df->time_in_state, 0, (df->profile->max_state *
> -					sizeof(*df->time_in_state)));
> -	memset(df->trans_table, 0, array3_size(sizeof(unsigned int),
> +	memset(df->stats.time_in_state, 0, (df->profile->max_state *
> +					sizeof(*df->stats.time_in_state)));
> +	memset(df->stats.trans_table, 0, array3_size(sizeof(unsigned int),
>  					df->profile->max_state,
>  					df->profile->max_state));
> -	df->total_trans = 0;
> -	df->last_stat_updated = get_jiffies_64();
> +	df->stats.total_trans = 0;
> +	df->stats.last_update = get_jiffies_64();
>  	mutex_unlock(&df->lock);
>  
>  	return count;
> diff --git a/include/linux/devfreq.h b/include/linux/devfreq.h
> index 41f15e7a22b8..de2fdc56aa5b 100644
> --- a/include/linux/devfreq.h
> +++ b/include/linux/devfreq.h
> @@ -106,6 +106,20 @@ struct devfreq_dev_profile {
>  	unsigned int max_state;
>  };
>  
> +/**
> + * struct devfreq_stats - Statistics of devfreq device behavior
> + * @total_trans:	Number of devfreq transitions.
> + * @trans_table:	Statistics of devfreq transitions.
> + * @time_in_state:	Statistics of devfreq states.
> + * @last_update:	The last time stats were updated.
> + */
> +struct devfreq_stats {
> +	unsigned int total_trans;
> +	unsigned int *trans_table;
> +	u64 *time_in_state;
> +	u64 last_update;
> +};
> +
>  /**
>   * struct devfreq - Device devfreq structure
>   * @node:	list node - contains the devices with devfreq that have been
> @@ -131,10 +145,7 @@ struct devfreq_dev_profile {
>   * @suspend_freq:	 frequency of a device set during suspend phase.
>   * @resume_freq:	 frequency of a device set in resume phase.
>   * @suspend_count:	 suspend requests counter for a device.
> - * @total_trans:	Number of devfreq transitions
> - * @trans_table:	Statistics of devfreq transitions
> - * @time_in_state:	Statistics of devfreq states
> - * @last_stat_updated:	The last time stat updated
> + * @stats:	Statistics of devfreq device behavior
>   * @transition_notifier_list: list head of DEVFREQ_TRANSITION_NOTIFIER notifier
>   *
>   * This structure stores the devfreq information for a give device.
> @@ -171,11 +182,8 @@ struct devfreq {
>  	unsigned long resume_freq;
>  	atomic_t suspend_count;
>  
> -	/* information for device frequency transition */
> -	unsigned int total_trans;
> -	unsigned int *trans_table;
> -	u64 *time_in_state;
> -	u64 last_stat_updated;
> +	/* information for device frequency transitions */
> +	struct devfreq_stats stats;
>  
>  	struct srcu_notifier_head transition_notifier_list;
>  };
> 

Applied it. Thanks.

-- 
Best Regards,
Chanwoo Choi
Samsung Electronics