Re: [PATCH v8 12/25] x86/resctrl: Remove MSR reading of event configuration value

[Moger, Babu]

Hi Reinette,

On 10/15/24 22:16, Reinette Chatre wrote:
> Hi Babu,
> 
> On 10/9/24 10:39 AM, Babu Moger wrote:
>> The event configuration is domain specific and initialized during domain
>> initialization. The values are stored in struct rdt_hw_mon_domain.
>>
>> It is not required to read the configuration register every time user asks
>> for it. Use the value stored in struct rdt_hw_mon_domain instead.
>>
>> Introduce resctrl_arch_mon_event_config_get() and
>> resctrl_arch_mon_event_config_set() to get/set architecture domain specific
>> mbm_total_cfg/mbm_local_cfg values.
>>
>> Signed-off-by: Babu Moger <babu.moger@xxxxxxx>
>> ---
> ...
> 
> 
>> +void resctrl_arch_mon_event_config_set(void *info)
>> +{
>> +	struct mon_config_info *mon_info = info;
>> +	struct rdt_hw_mon_domain *hw_dom;
>> +	unsigned int index;
>> +
>> +	index = mon_event_config_index_get(mon_info->evtid);
>> +	if (index == INVALID_CONFIG_INDEX)
>> +		return;
>> +
>> +	wrmsr(MSR_IA32_EVT_CFG_BASE + index, mon_info->mon_config, 0);
>> +
>> +	hw_dom = resctrl_to_arch_mon_dom(mon_info->d);
>> +
>> +	switch (mon_info->evtid) {
>> +	case QOS_L3_OCCUP_EVENT_ID:
>> +		break;
> 
> This check does no harm but I do not think it is necessary since earlier
> mon_event_config_index_get() would return INVALID_CONFIG_INDEX if the
> evtid is QOS_L3_OCCUP_EVENT_ID.

Sure. Will remove it.

> 
>> +	case QOS_L3_MBM_TOTAL_EVENT_ID:
>> +		hw_dom->mbm_total_cfg = mon_info->mon_config;
>> +		break;
>> +	case QOS_L3_MBM_LOCAL_EVENT_ID:
>> +		hw_dom->mbm_local_cfg =  mon_info->mon_config;
> 
> nit: unnecessary space

Sure.

> 
>> +		break;
>> +	}
>> +}
>> +
> 
> Reinette
> 
> 

-- 
Thanks
Babu Moger