linux-kernel - Re: [PATCH] cpufreq: governor: Free dbs_data directly when gov->init() fails

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Message-ID: <0c50a3da-65e2-eb91-95ea-6a2ca825c16d@huawei.com>
Date:   Mon, 28 Aug 2023 15:25:18 +0800
From:   "Liao, Chang" <liaochang1@...wei.com>
To:     Viresh Kumar <viresh.kumar@...aro.org>
CC:     <rafael@...nel.org>, <linux-pm@...r.kernel.org>,
        <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH] cpufreq: governor: Free dbs_data directly when
 gov->init() fails

Hi Viresh.

在 2023/8/28 14:56, Viresh Kumar 写道:
> On 26-08-23, 01:24, Liao Chang wrote:
>> Due to the kobject embedded in the dbs_data doest not has a release()
>> method yet, it needs to use kfree() to free dbs_data directly when
>> governor fails to allocate the tunner field of dbs_data.
>>
>> Signed-off-by: Liao Chang <liaochang1@...wei.com>
>> ---
>>  drivers/cpufreq/cpufreq_governor.c | 4 +++-
>>  1 file changed, 3 insertions(+), 1 deletion(-)
>>
>> diff --git a/drivers/cpufreq/cpufreq_governor.c b/drivers/cpufreq/cpufreq_governor.c
>> index 85da677c43d6..6e1ac864e87e 100644
>> --- a/drivers/cpufreq/cpufreq_governor.c
>> +++ b/drivers/cpufreq/cpufreq_governor.c
>> @@ -438,8 +438,10 @@ int cpufreq_dbs_governor_init(struct cpufreq_policy *policy)
>>  	gov_attr_set_init(&dbs_data->attr_set, &policy_dbs->list);
>>  
>>  	ret = gov->init(dbs_data);
>> -	if (ret)
>> +	if (ret) {
>> +		kfree(dbs_data);
>>  		goto free_policy_dbs_info;
>> +	}
> 
> What about this instead ?
> 
> diff --git a/drivers/cpufreq/cpufreq_governor.c b/drivers/cpufreq/cpufreq_governor.c
> index 85da677c43d6..af44ee6a6430 100644
> --- a/drivers/cpufreq/cpufreq_governor.c
> +++ b/drivers/cpufreq/cpufreq_governor.c
> @@ -439,7 +439,7 @@ int cpufreq_dbs_governor_init(struct cpufreq_policy *policy)
> 
>         ret = gov->init(dbs_data);
>         if (ret)
> -               goto free_policy_dbs_info;
> +               goto free_dbs_data;
> 
>         /*
>          * The sampling interval should not be less than the transition latency
> @@ -474,6 +474,8 @@ int cpufreq_dbs_governor_init(struct cpufreq_policy *policy)
>         if (!have_governor_per_policy())
>                 gov->gdbs_data = NULL;
>         gov->exit(dbs_data);
> +
> +free_dbs_data:
>         kfree(dbs_data);

Sure, less copy-and-paste code is better :)

Do you mind I copy above code in next revision?

Thanks.

> 
>  free_policy_dbs_info:
> 

-- 
BR
Liao, Chang