Re: [PATCH v8 24/25] x86/resctrl: Introduce interface to list assignment states of all the groups

["Moger, Babu" <babu.moger@amd.com>]

Hi Reinette,

On 10/15/24 22:40, Reinette Chatre wrote:
> Hi Babu,
> 
> On 10/9/24 10:39 AM, Babu Moger wrote:
>> Provide the interface to list the assignment states of all the resctrl
>> groups in mbm_cntr_assign mode.
>>
>> Example:
>> $mount -t resctrl resctrl /sys/fs/resctrl/
>> $cat /sys/fs/resctrl/info/L3_MON/mbm_assign_control
>> //0=tl;1=tl;
>>
>> List follows the following format:
>>
>> "<CTRL_MON group>/<MON group>/<domain_id>=<flags>"
>>
>> Format for specific type of groups:
>>
>> - Default CTRL_MON group:
>>   "//<domain_id>=<flags>"
>>
>> - Non-default CTRL_MON group:
>>   "<CTRL_MON group>//<domain_id>=<flags>"
>>
>> - Child MON group of default CTRL_MON group:
>>   "/<MON group>/<domain_id>=<flags>"
>>
>> - Child MON group of non-default CTRL_MON group:
>>   "<CTRL_MON group>/<MON group>/<domain_id>=<flags>"
>>
>> Flags can be one of the following:
>> t  MBM total event is enabled
>> l  MBM local event is enabled
>> tl Both total and local MBM events are enabled
>> _  None of the MBM events are enabled
>>
>> Signed-off-by: Babu Moger <babu.moger@amd.com>
>> ---
>> v8: Moved resctrl_mbm_event_assigned() in here as it is first used here.
>>     Moved rdt_last_cmd_clear() before making any call.
>>     Updated the commit log.
>>     Corrected the doc format.
>>
>> v7: Renamed the interface name from 'mbm_control' to 'mbm_assign_control'
>>     to match 'mbm_assign_mode'.
>>     Removed Arch references from FS code.
>>     Added rdt_last_cmd_clear() before the command processing.
>>     Added rdtgroup_mutex before all the calls.
>>     Removed references of ABMC from FS code.
>>
>> v6: The domain specific assignment can be determined looking at mbm_cntr_map.
>>     Removed rdtgroup_abmc_dom_cfg() and rdtgroup_abmc_dom_state().
>>     Removed the switch statement for the domain_state detection.
>>     Determined the flags incremently.
>>     Removed special handling of default group while printing..
>>
>> v5: Replaced "assignment flags" with "flags".
>>     Changes related to mon structure.
>>     Changes related renaming the interface from mbm_assign_control to
>>     mbm_control.
>>
>> v4: Added functionality to query domain specific assigment in.
>>     rdtgroup_abmc_dom_state().
>>
>> v3: New patch.
>>     Addresses the feedback to provide the global assignment interface.
>>     https://lore.kernel.org/lkml/c73f444b-83a1-4e9a-95d3-54c5165ee782@intel.com/
>> ---
>>  Documentation/arch/x86/resctrl.rst     | 44 +++++++++++++++
>>  arch/x86/kernel/cpu/resctrl/monitor.c  |  1 +
>>  arch/x86/kernel/cpu/resctrl/rdtgroup.c | 76 ++++++++++++++++++++++++++
>>  3 files changed, 121 insertions(+)
>>
>> diff --git a/Documentation/arch/x86/resctrl.rst b/Documentation/arch/x86/resctrl.rst
>> index d9574078f735..b85d3bc3e301 100644
>> --- a/Documentation/arch/x86/resctrl.rst
>> +++ b/Documentation/arch/x86/resctrl.rst
>> @@ -310,6 +310,50 @@ with the following files:
>>  	The number of monitoring counters available for assignment when the
>>  	architecture supports mbm_cntr_assign mode.
>>  
>> +"mbm_assign_control":
>> +	Reports the resctrl group and monitor status of each group.
>> +
>> +	List follows the following format:
>> +		"<CTRL_MON group>/<MON group>/<domain_id>=<flags>"
>> +
>> +	Format for specific type of groups:
>> +
>> +	* Default CTRL_MON group:
>> +		"//<domain_id>=<flags>"
>> +
>> +	* Non-default CTRL_MON group:
>> +		"<CTRL_MON group>//<domain_id>=<flags>"
>> +
>> +	* Child MON group of default CTRL_MON group:
>> +		"/<MON group>/<domain_id>=<flags>"
>> +
>> +	* Child MON group of non-default CTRL_MON group:
>> +		"<CTRL_MON group>/<MON group>/<domain_id>=<flags>"
>> +
>> +	Flags can be one of the following:
>> +	::
>> +
>> +	 t  MBM total event is assigned.
>> +	 l  MBM local event is assigned.
>> +	 tl Both total and local MBM events are assigned.
>> +	 _  None of the MBM events are assigned.
>> +
>> +	Examples:
>> +	::
>> +
>> +	 # mkdir /sys/fs/resctrl/mon_groups/child_default_mon_grp
>> +	 # mkdir /sys/fs/resctrl/non_default_ctrl_mon_grp
>> +	 # mkdir /sys/fs/resctrl/non_default_ctrl_mon_grp/mon_groups/child_non_default_mon_grp
>> +
>> +	 # cat /sys/fs/resctrl/info/L3_MON/mbm_assign_control
>> +	 non_default_ctrl_mon_grp//0=tl;1=tl;
>> +	 non_default_ctrl_mon_grp/child_non_default_mon_grp/0=tl;1=tl;
>> +	 //0=tl;1=tl;
>> +	 /child_default_mon_grp/0=tl;1=tl;
>> +
>> +	There are four resctrl groups. All the groups have total and local MBM events
>> +	assigned on domain 0 and 1.
>> +
>>  "max_threshold_occupancy":
>>  		Read/write file provides the largest value (in
>>  		bytes) at which a previously used LLC_occupancy
>> diff --git a/arch/x86/kernel/cpu/resctrl/monitor.c b/arch/x86/kernel/cpu/resctrl/monitor.c
>> index 395d99984893..fa7c77935080 100644
>> --- a/arch/x86/kernel/cpu/resctrl/monitor.c
>> +++ b/arch/x86/kernel/cpu/resctrl/monitor.c
>> @@ -1269,6 +1269,7 @@ int __init rdt_get_mon_l3_config(struct rdt_resource *r)
>>  			r->mon.num_mbm_cntrs = (ebx & GENMASK(15, 0)) + 1;
>>  			resctrl_file_fflags_init("num_mbm_cntrs", RFTYPE_MON_INFO);
>>  			hw_res->mbm_cntr_assign_enabled = true;
>> +			resctrl_file_fflags_init("mbm_assign_control", RFTYPE_MON_INFO);
>>  		}
>>  	}
>>  
>> diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
>> index cf2e0ad0e4f4..cf92ceb0f05e 100644
>> --- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
>> +++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
>> @@ -970,6 +970,76 @@ static int rdtgroup_num_mbm_cntrs_show(struct kernfs_open_file *of,
>>  	return 0;
>>  }
>>  
>> +static bool resctrl_mbm_event_assigned(struct rdtgroup *rdtg,
>> +				       struct rdt_mon_domain *d, u32 evtid)
> 
> u32 -> enum resctrl_event_id ?


Sure.

> 
>> +{
>> +	int index = MBM_EVENT_ARRAY_INDEX(evtid);
>> +	int cntr_id = rdtg->mon.cntr_id[index];
>> +
>> +	return cntr_id != MON_CNTR_UNSET && test_bit(cntr_id, d->mbm_cntr_map);
>> +}
>> +
>> +static char *rdtgroup_mon_state_to_str(struct rdtgroup *rdtgrp,
>> +				       struct rdt_mon_domain *d, char *str)
>> +{
>> +	char *tmp = str;
>> +
>> +	/* Query the total and local event flags for the domain */
>> +	if (resctrl_mbm_event_assigned(rdtgrp, d, QOS_L3_MBM_TOTAL_EVENT_ID))
>> +		*tmp++ = 't';
>> +
>> +	if (resctrl_mbm_event_assigned(rdtgrp, d, QOS_L3_MBM_LOCAL_EVENT_ID))
>> +		*tmp++ = 'l';
>> +
>> +	if (tmp == str)
>> +		*tmp++ = '_';
>> +
>> +	*tmp = '\0';
>> +	return str;
>> +}
>> +
> 
> Reinette
> 
> 

-- 
Thanks
Babu Moger