2023-09-12 19:04:46

by Reinette Chatre

[permalink] [raw]
Subject: Re: [PATCH v9 9/9] x86/resctrl: Display RMID of resource group

Hi Babu,

On 9/12/2023 10:39 AM, Moger, Babu wrote:
> On 9/11/23 18:08, Reinette Chatre wrote:
>> Hi Babu,
>>
>> On 9/7/2023 4:51 PM, Babu Moger wrote:
>>> In x86, hardware uses RMID to identify a a monitoring group. When a
>>> user creates a monitor group these details are not visible. These details
>>> can help resctrl debugging.
>>>
>>> Add RMID(mon_hw_id) to the monitor groups display in resctrl interface.
>>> Users can see these details when resctrl is mounted with "-o debug" option.
>>>
>>> Other architectures do not use "RMID". Use the name mon_hw_id to refer
>>> to "RMID" in an effort to keep the naming generic.
>>>
>>> Add the flag RFTYPE_MON_BASE, which contains the files required only
>>> for the MON group.
>>
>> As I mentioned in [1] I believe adding support for files with RFTYPE_MON flag
>> to resctrl needs to be in a separate patch. With the core support added a file
>> with this flag can be introduced separately.
>
> Yes. We discussed it. Thought it may not fit as a separate patch on its
> own. So, i combined it.
>
> Now, I split patch 9 into two. Let me know if it looks ok.
>
> ==========================================================================
>
> Author: Babu Moger <[email protected]>
> Date: Thu Sep 7 18:51:28 2023 -0500
>
> x86/resctrl: Add RFTYPE_MON_BASE for MON groups
>
> Add the flag RFTYPE_MON_BASE, which contains the files required only
> for the MON group. Files with these flags are only visible when
> monitoring is enabled.
>
> Signed-off-by: Babu Moger <[email protected]>
>
> diff --git a/arch/x86/kernel/cpu/resctrl/internal.h
> b/arch/x86/kernel/cpu/resctrl/internal.h
> index ccdbed615d41..72988e5c52a7 100644
> --- a/arch/x86/kernel/cpu/resctrl/internal.h
> +++ b/arch/x86/kernel/cpu/resctrl/internal.h
> @@ -296,6 +296,8 @@ struct rdtgroup {
> * --> RFTYPE_BASE (Files common for both MON and CTRL groups)
> * Files: cpus, cpus_list, tasks
> *
> + * --> RFTYPE_MON (Files only for MON group)
> + *
> * --> RFTYPE_CTRL (Files only for CTRL group)
> * Files: mode, schemata, size
> *

I think it would be ok to add above hunk as part of the patch
that adds mon_hw_id, similar to what you did in patch 8.

> @@ -315,6 +317,7 @@ struct rdtgroup {
> #define RFTYPE_MON_INFO (RFTYPE_INFO | RFTYPE_MON)
> #define RFTYPE_TOP_INFO (RFTYPE_INFO | RFTYPE_TOP)
> #define RFTYPE_CTRL_BASE (RFTYPE_BASE | RFTYPE_CTRL)
> +#define RFTYPE_MON_BASE (RFTYPE_BASE | RFTYPE_MON)
>

This hunk may be appropriate for patch 3.

> /* List of all resource groups */
> extern struct list_head rdt_all_groups;
>

This is not how I expected it to look. There is currently an issue
in resctrl where files with RFTYPE_MON are not created for CTRL_MON
groups. This has not actually been a problem because there are
no files with the RFTYPE_MON flag. This series introduces the first
file with RFTYPE_MON flag and thus this resctrl issue needs to be fixed
before this new file can be supported.

Considering this I expected to see the changes in rdt_get_tree()
and mkdir_rdt_prepare() done as a separate patch. This will add
support for RFTYPE_MON files to resctrl. After this change
a separate patch can add the file that has this flag.

Reinette


2023-09-13 01:36:47

by Moger, Babu

[permalink] [raw]
Subject: Re: [PATCH v9 9/9] x86/resctrl: Display RMID of resource group

Hi Reinette,

On 9/12/23 12:57, Reinette Chatre wrote:
> Hi Babu,
>
> On 9/12/2023 10:39 AM, Moger, Babu wrote:
>> On 9/11/23 18:08, Reinette Chatre wrote:
>>> Hi Babu,
>>>
>>> On 9/7/2023 4:51 PM, Babu Moger wrote:
>>>> In x86, hardware uses RMID to identify a a monitoring group. When a
>>>> user creates a monitor group these details are not visible. These details
>>>> can help resctrl debugging.
>>>>
>>>> Add RMID(mon_hw_id) to the monitor groups display in resctrl interface.
>>>> Users can see these details when resctrl is mounted with "-o debug" option.
>>>>
>>>> Other architectures do not use "RMID". Use the name mon_hw_id to refer
>>>> to "RMID" in an effort to keep the naming generic.
>>>>
>>>> Add the flag RFTYPE_MON_BASE, which contains the files required only
>>>> for the MON group.
>>>
>>> As I mentioned in [1] I believe adding support for files with RFTYPE_MON flag
>>> to resctrl needs to be in a separate patch. With the core support added a file
>>> with this flag can be introduced separately.
>>
>> Yes. We discussed it. Thought it may not fit as a separate patch on its
>> own. So, i combined it.
>>
>> Now, I split patch 9 into two. Let me know if it looks ok.
>>
>> ==========================================================================
>>
>> Author: Babu Moger <[email protected]>
>> Date: Thu Sep 7 18:51:28 2023 -0500
>>
>> x86/resctrl: Add RFTYPE_MON_BASE for MON groups
>>
>> Add the flag RFTYPE_MON_BASE, which contains the files required only
>> for the MON group. Files with these flags are only visible when
>> monitoring is enabled.
>>
>> Signed-off-by: Babu Moger <[email protected]>
>>
>> diff --git a/arch/x86/kernel/cpu/resctrl/internal.h
>> b/arch/x86/kernel/cpu/resctrl/internal.h
>> index ccdbed615d41..72988e5c52a7 100644
>> --- a/arch/x86/kernel/cpu/resctrl/internal.h
>> +++ b/arch/x86/kernel/cpu/resctrl/internal.h
>> @@ -296,6 +296,8 @@ struct rdtgroup {
>> * --> RFTYPE_BASE (Files common for both MON and CTRL groups)
>> * Files: cpus, cpus_list, tasks
>> *
>> + * --> RFTYPE_MON (Files only for MON group)
>> + *
>> * --> RFTYPE_CTRL (Files only for CTRL group)
>> * Files: mode, schemata, size
>> *
>
> I think it would be ok to add above hunk as part of the patch
> that adds mon_hw_id, similar to what you did in patch 8.

Ok. Sure.
>
>> @@ -315,6 +317,7 @@ struct rdtgroup {
>> #define RFTYPE_MON_INFO (RFTYPE_INFO | RFTYPE_MON)
>> #define RFTYPE_TOP_INFO (RFTYPE_INFO | RFTYPE_TOP)
>> #define RFTYPE_CTRL_BASE (RFTYPE_BASE | RFTYPE_CTRL)
>> +#define RFTYPE_MON_BASE (RFTYPE_BASE | RFTYPE_MON)
>>
>
> This hunk may be appropriate for patch 3.

Sure.

>
>> /* List of all resource groups */
>> extern struct list_head rdt_all_groups;
>>
>
> This is not how I expected it to look. There is currently an issue
> in resctrl where files with RFTYPE_MON are not created for CTRL_MON
> groups. This has not actually been a problem because there are
> no files with the RFTYPE_MON flag. This series introduces the first
> file with RFTYPE_MON flag and thus this resctrl issue needs to be fixed
> before this new file can be supported.
Yes.
>
> Considering this I expected to see the changes in rdt_get_tree()
> and mkdir_rdt_prepare() done as a separate patch. This will add
> support for RFTYPE_MON files to resctrl. After this change
> a separate patch can add the file that has this flag.
>
Sure. Got it.
Thanks
Babu Moger