Re: [PATCH v8 6/6] cpufreq: powernv: Add sysfs attributes to show throttle stats

From: Shilpasri G Bhat
Date: Wed Feb 03 2016 - 03:42:49 EST


Hi,

On 02/03/2016 01:57 PM, Viresh Kumar wrote:
> On 03-02-16, 01:11, Shilpasri G Bhat wrote:
>> static int init_chip_info(void)
>> {
>> unsigned int chip[256];
>> - unsigned int cpu, i;
>> + unsigned int cpu;
>> unsigned int prev_chip_id = UINT_MAX;
>> cpumask_t cpu_mask;
>> - int ret = -ENOMEM;
>> + int i, j, ret = -ENOMEM;
>>
>> core_to_chip_map = kcalloc(cpu_nr_cores(), sizeof(unsigned int),
>> GFP_KERNEL);
>> @@ -583,12 +711,51 @@ static int init_chip_info(void)
>> goto free_chip_map;
>>
>> for (i = 0; i < nr_chips; i++) {
>> + char name[10];
>> +
>> chips[i].id = chip[i];
>> cpumask_copy(&chips[i].mask, cpumask_of_node(chip[i]));
>> INIT_WORK(&chips[i].throttle, powernv_cpufreq_work_fn);
>> +
>> + for (j = 0; j <= OCC_MAX_THROTTLE_STATUS; j++) {
>> + chips[i].reason[j] =
>> + kcalloc(powernv_pstate_info.nr_pstates,
>> + sizeof(int), GFP_KERNEL);
>> + if (!chips[i].reason[j]) {
>> + ret = -ENOMEM;
>> + goto free_chip;
>> + }
>> + }
>> +
>> + snprintf(name, sizeof(name), "chip%d", chips[i].id);
>> + ret = kobject_init_and_add(&chips[i].kobj,
>> + get_ktype(cpufreq_global_kobject),
>
> Sorry but why do you need to create a kobject here ? A simple
> sysfs_create_group() can create groups (directories) for you.

I need the chip-id in the <attr>_show(). With just sysfs_create_group() I will
get the cpufreq_global_kobject in the <attr>_show() and I will not be able to
figure out the chip-id.

Thanks and Regards,
Shilpa
>
>> + cpufreq_global_kobject, name);
>> + if (ret)
>> + goto free_chip;
>> +
>> + ret = sysfs_create_group(&chips[i].kobj, &throttle_stat_group);
>> + if (ret) {
>> + pr_info("Chip %d failed to create throttle sysfs group\n",
>> + chips[i].id);
>> + goto free_kobject;
>> + }
>> }
>