[PATCH v16 29/34] fs/resctrl: Introduce mbm_L3_assignments to list assignments in a group

Babu Moger posted 34 patches 2 months, 1 week ago
There is a newer version of this series
[PATCH v16 29/34] fs/resctrl: Introduce mbm_L3_assignments to list assignments in a group
Posted by Babu Moger 2 months, 1 week ago
Introduce the mbm_L3_assignments resctrl file associated with CTRL_MON and
MON resource groups to display the counter assignment states of the
resource group when "mbm_event" counter assignment mode is enabled.

The list is displayed in the following format:
<Event>:<Domain id>=<Assignment state>;<Domain id>=<Assignment state>

Event: A valid MBM event listed in
       /sys/fs/resctrl/info/L3_MON/event_configs directory.

Domain ID: A valid domain ID.

The assignment state can be one of the following:

_ : No counter assigned.

e : Counter assigned exclusively.

Example:
To list the assignment states for the default group
$ cd /sys/fs/resctrl
$ cat /sys/fs/resctrl/mbm_L3_assignments
mbm_total_bytes:0=e;1=e
mbm_local_bytes:0=e;1=e

Signed-off-by: Babu Moger <babu.moger@amd.com>
---
v16: Fixed minor merge conflicts with code displacement.
     Changed the check with mbm_cntr_get() to "< 0" from " >=".

v15: Updated the changelog with Reinette's text.
     Updated the event format list to list multiple domains.
     Changed the goto out_assing to out_unlock.
     Updated to use new loop for_each_mon_event() instead of hardcoding.

v14: Added missed rdtgroup_kn_lock_live on failure case.
     Updated the user doc resctrl.rst to clarify counter assignments.
     Updated the changelog.

v13: Changelog update.
     Few changes in mbm_L3_assignments_show() after moving the event config to evt_list.
     Resolved conflicts caused by the recent FS/ARCH code restructure.
     The rdtgroup.c/monitor.c files have been split between the FS and ARCH directories.

v12: New patch:
     Assignment interface moved inside the group based the discussion
     https://lore.kernel.org/lkml/CALPaoCiii0vXOF06mfV=kVLBzhfNo0SFqt4kQGwGSGVUqvr2Dg@mail.gmail.com/#t
---
 Documentation/filesystems/resctrl.rst | 28 ++++++++++++++
 fs/resctrl/monitor.c                  |  1 +
 fs/resctrl/rdtgroup.c                 | 54 +++++++++++++++++++++++++++
 3 files changed, 83 insertions(+)

diff --git a/Documentation/filesystems/resctrl.rst b/Documentation/filesystems/resctrl.rst
index 165e0d315af7..0b8ce942f112 100644
--- a/Documentation/filesystems/resctrl.rst
+++ b/Documentation/filesystems/resctrl.rst
@@ -514,6 +514,34 @@ When the "mba_MBps" mount option is used all CTRL_MON groups will also contain:
 	/sys/fs/resctrl/info/L3_MON/mon_features changes the input
 	event.
 
+"mbm_L3_assignments":
+	Exists when "mbm_event" counter assignment mode is supported and lists the
+	counter assignment states of the group.
+
+	The assignment list is displayed in the following format:
+
+	<Event>:<Domain ID>=<Assignment state>;<Domain ID>=<Assignment state>
+
+	Event: A valid MBM event in the
+	       /sys/fs/resctrl/info/L3_MON/event_configs directory.
+
+	Domain ID: A valid domain ID.
+
+	Assignment states:
+
+	_ : No counter assigned.
+
+	e : Counter assigned exclusively.
+
+	Example:
+	To display the counter assignment states for the default group.
+	::
+
+	 # cd /sys/fs/resctrl
+	 # cat /sys/fs/resctrl/mbm_L3_assignments
+	   mbm_total_bytes:0=e;1=e
+	   mbm_local_bytes:0=e;1=e
+
 Resource allocation rules
 -------------------------
 
diff --git a/fs/resctrl/monitor.c b/fs/resctrl/monitor.c
index 5cf1b79c17f5..ebc049105949 100644
--- a/fs/resctrl/monitor.c
+++ b/fs/resctrl/monitor.c
@@ -1080,6 +1080,7 @@ int resctrl_mon_resource_init(void)
 		resctrl_file_fflags_init("event_filter", RFTYPE_ASSIGN_CONFIG);
 		resctrl_file_fflags_init("mbm_assign_on_mkdir", RFTYPE_MON_INFO |
 					 RFTYPE_RES_CACHE);
+		resctrl_file_fflags_init("mbm_L3_assignments", RFTYPE_MON_BASE);
 	}
 
 	return 0;
diff --git a/fs/resctrl/rdtgroup.c b/fs/resctrl/rdtgroup.c
index d087ba990cd3..47716e623a9c 100644
--- a/fs/resctrl/rdtgroup.c
+++ b/fs/resctrl/rdtgroup.c
@@ -1931,6 +1931,54 @@ static ssize_t resctrl_mbm_assign_on_mkdir_write(struct kernfs_open_file *of,
 	return nbytes;
 }
 
+static int mbm_L3_assignments_show(struct kernfs_open_file *of, struct seq_file *s, void *v)
+{
+	struct rdt_resource *r = resctrl_arch_get_resource(RDT_RESOURCE_L3);
+	struct rdt_mon_domain *d;
+	struct rdtgroup *rdtgrp;
+	struct mon_evt *mevt;
+	int ret = 0;
+	bool sep;
+
+	rdtgrp = rdtgroup_kn_lock_live(of->kn);
+	if (!rdtgrp) {
+		ret = -ENOENT;
+		goto out_unlock;
+	}
+
+	rdt_last_cmd_clear();
+	if (!resctrl_arch_mbm_cntr_assign_enabled(r)) {
+		rdt_last_cmd_puts("mbm_event mode is not enabled\n");
+		ret = -ENOENT;
+		goto out_unlock;
+	}
+
+	for_each_mon_event(mevt) {
+		if (mevt->rid != r->rid || !mevt->enabled || !resctrl_is_mbm_event(mevt->evtid))
+			continue;
+
+		sep = false;
+		seq_printf(s, "%s:", mevt->name);
+		list_for_each_entry(d, &r->mon_domains, hdr.list) {
+			if (sep)
+				seq_putc(s, ';');
+
+			if (mbm_cntr_get(r, d, rdtgrp, mevt->evtid) < 0)
+				seq_printf(s, "%d=_", d->hdr.id);
+			else
+				seq_printf(s, "%d=e", d->hdr.id);
+
+			sep = true;
+		}
+		seq_putc(s, '\n');
+	}
+
+out_unlock:
+	rdtgroup_kn_unlock(of->kn);
+
+	return ret;
+}
+
 /* rdtgroup information files for one cache resource. */
 static struct rftype res_common_files[] = {
 	{
@@ -2069,6 +2117,12 @@ static struct rftype res_common_files[] = {
 		.seq_show	= event_filter_show,
 		.write		= event_filter_write,
 	},
+	{
+		.name		= "mbm_L3_assignments",
+		.mode		= 0444,
+		.kf_ops		= &rdtgroup_kf_single_ops,
+		.seq_show	= mbm_L3_assignments_show,
+	},
 	{
 		.name		= "mbm_assign_mode",
 		.mode		= 0444,
-- 
2.34.1
Re: [PATCH v16 29/34] fs/resctrl: Introduce mbm_L3_assignments to list assignments in a group
Posted by Reinette Chatre 2 months, 1 week ago
Hi Babu,

On 7/25/25 11:29 AM, Babu Moger wrote:
> Introduce the mbm_L3_assignments resctrl file associated with CTRL_MON and
> MON resource groups to display the counter assignment states of the
> resource group when "mbm_event" counter assignment mode is enabled.
> 
> The list is displayed in the following format:

needs imperative:
 "Display the list ..."

> <Event>:<Domain id>=<Assignment state>;<Domain id>=<Assignment state>
> 
> Event: A valid MBM event listed in
>        /sys/fs/resctrl/info/L3_MON/event_configs directory.
> 
> Domain ID: A valid domain ID.
> 
> The assignment state can be one of the following:
> 
> _ : No counter assigned.
> 
> e : Counter assigned exclusively.
> 
> Example:
> To list the assignment states for the default group
> $ cd /sys/fs/resctrl
> $ cat /sys/fs/resctrl/mbm_L3_assignments
> mbm_total_bytes:0=e;1=e
> mbm_local_bytes:0=e;1=e
> 
> Signed-off-by: Babu Moger <babu.moger@amd.com>
> ---

...


> diff --git a/fs/resctrl/monitor.c b/fs/resctrl/monitor.c
> index 5cf1b79c17f5..ebc049105949 100644
> --- a/fs/resctrl/monitor.c
> +++ b/fs/resctrl/monitor.c
> @@ -1080,6 +1080,7 @@ int resctrl_mon_resource_init(void)
>  		resctrl_file_fflags_init("event_filter", RFTYPE_ASSIGN_CONFIG);
>  		resctrl_file_fflags_init("mbm_assign_on_mkdir", RFTYPE_MON_INFO |
>  					 RFTYPE_RES_CACHE);
> +		resctrl_file_fflags_init("mbm_L3_assignments", RFTYPE_MON_BASE);
>  	}
>  
>  	return 0;
> diff --git a/fs/resctrl/rdtgroup.c b/fs/resctrl/rdtgroup.c
> index d087ba990cd3..47716e623a9c 100644
> --- a/fs/resctrl/rdtgroup.c
> +++ b/fs/resctrl/rdtgroup.c
> @@ -1931,6 +1931,54 @@ static ssize_t resctrl_mbm_assign_on_mkdir_write(struct kernfs_open_file *of,
>  	return nbytes;
>  }
>  
> +static int mbm_L3_assignments_show(struct kernfs_open_file *of, struct seq_file *s, void *v)

Please move to monitor.c (then mbm_cntr_get() can be private to monitor.c also).

> +{
> +	struct rdt_resource *r = resctrl_arch_get_resource(RDT_RESOURCE_L3);
> +	struct rdt_mon_domain *d;
> +	struct rdtgroup *rdtgrp;
> +	struct mon_evt *mevt;
> +	int ret = 0;
> +	bool sep;
> +
> +	rdtgrp = rdtgroup_kn_lock_live(of->kn);
> +	if (!rdtgrp) {
> +		ret = -ENOENT;
> +		goto out_unlock;
> +	}
> +
> +	rdt_last_cmd_clear();
> +	if (!resctrl_arch_mbm_cntr_assign_enabled(r)) {
> +		rdt_last_cmd_puts("mbm_event mode is not enabled\n");
> +		ret = -ENOENT;

The error returned by the files when "mbm_event" is disabled (but supported) is
inconsistent. All but this one return EINVAL. Please make return code consistent.

> +		goto out_unlock;
> +	}
> +
> +	for_each_mon_event(mevt) {
> +		if (mevt->rid != r->rid || !mevt->enabled || !resctrl_is_mbm_event(mevt->evtid))
> +			continue;
> +
> +		sep = false;
> +		seq_printf(s, "%s:", mevt->name);
> +		list_for_each_entry(d, &r->mon_domains, hdr.list) {
> +			if (sep)
> +				seq_putc(s, ';');
> +
> +			if (mbm_cntr_get(r, d, rdtgrp, mevt->evtid) < 0)
> +				seq_printf(s, "%d=_", d->hdr.id);
> +			else
> +				seq_printf(s, "%d=e", d->hdr.id);
> +
> +			sep = true;
> +		}
> +		seq_putc(s, '\n');
> +	}
> +
> +out_unlock:
> +	rdtgroup_kn_unlock(of->kn);
> +
> +	return ret;
> +}
> +
>  /* rdtgroup information files for one cache resource. */
>  static struct rftype res_common_files[] = {
>  	{

Reinette
Re: [PATCH v16 29/34] fs/resctrl: Introduce mbm_L3_assignments to list assignments in a group
Posted by Moger, Babu 1 month, 3 weeks ago
Hi Reinette,

On 7/30/2025 3:09 PM, Reinette Chatre wrote:
> Hi Babu,
>
> On 7/25/25 11:29 AM, Babu Moger wrote:
>> Introduce the mbm_L3_assignments resctrl file associated with CTRL_MON and
>> MON resource groups to display the counter assignment states of the
>> resource group when "mbm_event" counter assignment mode is enabled.
>>
>> The list is displayed in the following format:
> needs imperative:
>   "Display the list ..."
Sure.
>
>> <Event>:<Domain id>=<Assignment state>;<Domain id>=<Assignment state>
>>
>> Event: A valid MBM event listed in
>>         /sys/fs/resctrl/info/L3_MON/event_configs directory.
>>
>> Domain ID: A valid domain ID.
>>
>> The assignment state can be one of the following:
>>
>> _ : No counter assigned.
>>
>> e : Counter assigned exclusively.
>>
>> Example:
>> To list the assignment states for the default group
>> $ cd /sys/fs/resctrl
>> $ cat /sys/fs/resctrl/mbm_L3_assignments
>> mbm_total_bytes:0=e;1=e
>> mbm_local_bytes:0=e;1=e
>>
>> Signed-off-by: Babu Moger <babu.moger@amd.com>
>> ---
> ...
>
>
>> diff --git a/fs/resctrl/monitor.c b/fs/resctrl/monitor.c
>> index 5cf1b79c17f5..ebc049105949 100644
>> --- a/fs/resctrl/monitor.c
>> +++ b/fs/resctrl/monitor.c
>> @@ -1080,6 +1080,7 @@ int resctrl_mon_resource_init(void)
>>   		resctrl_file_fflags_init("event_filter", RFTYPE_ASSIGN_CONFIG);
>>   		resctrl_file_fflags_init("mbm_assign_on_mkdir", RFTYPE_MON_INFO |
>>   					 RFTYPE_RES_CACHE);
>> +		resctrl_file_fflags_init("mbm_L3_assignments", RFTYPE_MON_BASE);
>>   	}
>>   
>>   	return 0;
>> diff --git a/fs/resctrl/rdtgroup.c b/fs/resctrl/rdtgroup.c
>> index d087ba990cd3..47716e623a9c 100644
>> --- a/fs/resctrl/rdtgroup.c
>> +++ b/fs/resctrl/rdtgroup.c
>> @@ -1931,6 +1931,54 @@ static ssize_t resctrl_mbm_assign_on_mkdir_write(struct kernfs_open_file *of,
>>   	return nbytes;
>>   }
>>   
>> +static int mbm_L3_assignments_show(struct kernfs_open_file *of, struct seq_file *s, void *v)
> Please move to monitor.c (then mbm_cntr_get() can be private to monitor.c also).


Sure.

>
>> +{
>> +	struct rdt_resource *r = resctrl_arch_get_resource(RDT_RESOURCE_L3);
>> +	struct rdt_mon_domain *d;
>> +	struct rdtgroup *rdtgrp;
>> +	struct mon_evt *mevt;
>> +	int ret = 0;
>> +	bool sep;
>> +
>> +	rdtgrp = rdtgroup_kn_lock_live(of->kn);
>> +	if (!rdtgrp) {
>> +		ret = -ENOENT;
>> +		goto out_unlock;
>> +	}
>> +
>> +	rdt_last_cmd_clear();
>> +	if (!resctrl_arch_mbm_cntr_assign_enabled(r)) {
>> +		rdt_last_cmd_puts("mbm_event mode is not enabled\n");
>> +		ret = -ENOENT;
> The error returned by the files when "mbm_event" is disabled (but supported) is
> inconsistent. All but this one return EINVAL. Please make return code consistent.


Yes. Sure.

>
>> +		goto out_unlock;
>> +	}
>> +
>> +	for_each_mon_event(mevt) {
>> +		if (mevt->rid != r->rid || !mevt->enabled || !resctrl_is_mbm_event(mevt->evtid))
>> +			continue;
>> +
>> +		sep = false;
>> +		seq_printf(s, "%s:", mevt->name);
>> +		list_for_each_entry(d, &r->mon_domains, hdr.list) {
>> +			if (sep)
>> +				seq_putc(s, ';');
>> +
>> +			if (mbm_cntr_get(r, d, rdtgrp, mevt->evtid) < 0)
>> +				seq_printf(s, "%d=_", d->hdr.id);
>> +			else
>> +				seq_printf(s, "%d=e", d->hdr.id);
>> +
>> +			sep = true;
>> +		}
>> +		seq_putc(s, '\n');
>> +	}
>> +
>> +out_unlock:
>> +	rdtgroup_kn_unlock(of->kn);
>> +
>> +	return ret;
>> +}
>> +
>>   /* rdtgroup information files for one cache resource. */
>>   static struct rftype res_common_files[] = {
>>   	{
> Reinette
>