linux-kernel - Re: [PATCH] cpufreq: ondemand: Allow powersave_bias_target() to bail out if freq

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Message-ID: <20231005105337.ozxgstfz45bskca5@vireshk-i7>
Date:   Thu, 5 Oct 2023 16:23:37 +0530
From:   Viresh Kumar <viresh.kumar@...aro.org>
To:     Liao Chang <liaochang1@...wei.com>
Cc:     rafael@...nel.org, linux-pm@...r.kernel.org,
        linux-kernel@...r.kernel.org
Subject: Re: [PATCH] cpufreq: ondemand: Allow powersave_bias_target() to bail
 out if freq_table is unsorted

On 08-09-23, 03:16, Liao Chang wrote:
> The generic_powersave_bias_target() function uses the
> cpufreq_table_find_index_[h/l]() functions to calculate the frequency
> bounds for the powersave bias target. However, these two functions only
> work on sorted frequency tables. Therefore, the
> generic_powersave_bias_target() function should bail out early if the
> frequency table is unsorted.
> 
> Signed-off-by: Liao Chang <liaochang1@...wei.com>
> ---
>  drivers/cpufreq/cpufreq_ondemand.c | 3 ++-
>  1 file changed, 2 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/cpufreq/cpufreq_ondemand.c b/drivers/cpufreq/cpufreq_ondemand.c
> index c52d19d67557..f7ff94f71395 100644
> --- a/drivers/cpufreq/cpufreq_ondemand.c
> +++ b/drivers/cpufreq/cpufreq_ondemand.c
> @@ -71,7 +71,8 @@ static unsigned int generic_powersave_bias_target(struct cpufreq_policy *policy,
>  	struct od_dbs_tuners *od_tuners = dbs_data->tuners;
>  	struct cpufreq_frequency_table *freq_table = policy->freq_table;
>  
> -	if (!freq_table) {
> +	if (!freq_table ||
> +	    WARN_ON_ONCE(policy->freq_table_sorted == CPUFREQ_TABLE_UNSORTED)) {
>  		dbs_info->freq_lo = 0;
>  		dbs_info->freq_lo_delay_us = 0;
>  		return freq_next;

Shouldn't we make the governor use the generic functions then ?
cpufreq_frequency_table_target() ?

> -- 
> 2.34.1

-- 
viresh