RE: [PATCH v12 01/17] EDAC: Add support for EDAC device features control

[Shiju Jose <shiju.jose@huawei.com>]

Thanks for reviewing.

>-----Original Message-----
>From: Borislav Petkov <bp@alien8.de>
>Sent: 13 September 2024 17:41
>To: Shiju Jose <shiju.jose@huawei.com>
>Cc: linux-edac@vger.kernel.org; linux-cxl@vger.kernel.org; linux-
>acpi@vger.kernel.org; linux-mm@kvack.org; linux-kernel@vger.kernel.org;
>tony.luck@intel.com; rafael@kernel.org; lenb@kernel.org;
>mchehab@kernel.org; dan.j.williams@intel.com; dave@stgolabs.net; Jonathan
>Cameron <jonathan.cameron@huawei.com>; dave.jiang@intel.com;
>alison.schofield@intel.com; vishal.l.verma@intel.com; ira.weiny@intel.com;
>david@redhat.com; Vilas.Sridharan@amd.com; leo.duran@amd.com;
>Yazen.Ghannam@amd.com; rientjes@google.com; jiaqiyan@google.com;
>Jon.Grimm@amd.com; dave.hansen@linux.intel.com;
>naoya.horiguchi@nec.com; james.morse@arm.com; jthoughton@google.com;
>somasundaram.a@hpe.com; erdemaktas@google.com; pgonda@google.com;
>duenwen@google.com; mike.malvestuto@intel.com; gthelen@google.com;
>wschwartz@amperecomputing.com; dferguson@amperecomputing.com;
>wbs@os.amperecomputing.com; nifan.cxl@gmail.com; jgroves@micron.com;
>vsalve@micron.com; tanxiaofei <tanxiaofei@huawei.com>; Zengtao (B)
><prime.zeng@hisilicon.com>; Roberto Sassu <roberto.sassu@huawei.com>;
>kangkang.shen@futurewei.com; wanghuiqiang <wanghuiqiang@huawei.com>;
>Linuxarm <linuxarm@huawei.com>
>Subject: Re: [PATCH v12 01/17] EDAC: Add support for EDAC device features
>control
>
>On Wed, Sep 11, 2024 at 10:04:30AM +0100, shiju.jose@huawei.com wrote:
>> +/**
>> + * edac_dev_feature_init - Init a RAS feature
>> + * @parent: client device.
>> + * @dev_data: pointer to the edac_dev_data structure, which contains
>> + * client device specific info.
>> + * @feat: pointer to struct edac_dev_feature.
>> + * @attr_groups: pointer to attribute group's container.
>> + *
>> + * Returns number of scrub features attribute groups on success,
>
>Not "scrub" - this is an interface initializing a generic feature.
Will correct.
>
>> + * error otherwise.
>> + */
>> +static int edac_dev_feat_init(struct device *parent,
>> +			      struct edac_dev_data *dev_data,
>> +			      const struct edac_dev_feature *ras_feat,
>> +			      const struct attribute_group **attr_groups) {
>> +	int num;
>> +
>> +	switch (ras_feat->ft_type) {
>> +	case RAS_FEAT_SCRUB:
>> +		dev_data->scrub_ops = ras_feat->scrub_ops;
>> +		dev_data->private = ras_feat->ctx;
>> +		return 1;
>> +	case RAS_FEAT_ECS:
>> +		num = ras_feat->ecs_info.num_media_frus;
>> +		dev_data->ecs_ops = ras_feat->ecs_ops;
>> +		dev_data->private = ras_feat->ctx;
>> +		return num;
>> +	case RAS_FEAT_PPR:
>> +		dev_data->ppr_ops = ras_feat->ppr_ops;
>> +		dev_data->private = ras_feat->ctx;
>> +		return 1;
>> +	default:
>> +		return -EINVAL;
>> +	}
>> +}
>
>And why does this function even exist and has kernel-doc comments when all it
>does is assign a couple of values? And it gets called exactly once?
>
>Just merge its body into the call site. There you can reuse the switch-case there
>too. No need for too much noodling around.
edac_dev_feat_init () function is updated with feature specific function call() etc in subsequent
EDAC feature specific patches. Thus added a separate function.   
>
>> diff --git a/include/linux/edac.h b/include/linux/edac.h index
>> b4ee8961e623..b337254cf5b8 100644
>> --- a/include/linux/edac.h
>> +++ b/include/linux/edac.h
>> @@ -661,4 +661,59 @@ static inline struct dimm_info
>> *edac_get_dimm(struct mem_ctl_info *mci,
>>
>>  	return mci->dimms[index];
>>  }
>> +
>> +/* EDAC device features */
>> +
>> +#define EDAC_FEAT_NAME_LEN	128
>> +
>> +/* RAS feature type */
>> +enum edac_dev_feat {
>> +	RAS_FEAT_SCRUB,
>> +	RAS_FEAT_ECS,
>> +	RAS_FEAT_PPR,
>> +	RAS_FEAT_MAX
>
>I still don't know what ECS or PPR is.
I will add comment/documentation here with a short explanation of features
if that make sense?
Each feature is described in the subsequent EDAC feature specific patches. 
>
>--
>Regards/Gruss,
>    Boris.
>
>https://people.kernel.org/tglx/notes-about-netiquette

Thanks,
Shiju