Re: [PATCH v7 09/10] fs/resctrl: Modify rdt_parse_data to pass mode and CLOSID

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

Hi Reinette,

On 7/21/25 22:30, Reinette Chatre wrote:
> Hi Babu,
> 
> On 7/10/25 10:16 AM, Babu Moger wrote:
>> The functions parse_cbm() and parse_bw() require mode and CLOSID to
> 
> No need to say "function" when using (). Also, drop parse_bw(), since it
> does not validate CBMs.

Sure.
> 
>> validate the Capacity Bit Mask (CBM). It is passed through struct
> 
> "passed through" -> "passed via"?
> 

Sure.

>> rdtgroup in rdt_parse_data.
> 
> "rdt_parse_data" -> "struct rdt_parse_data"
> 

Sure.

>>
>> This can be simplified by passing the mode and closid directly, instead of
> 
> closid -> CLOSID
> 
Sure,

>> through the rdtgroup struct. Doing so also facilitates calling parse_cbm()
>> to verify the CBM within the io_alloc feature, since io_alloc does not
>> have rdtgroup context.
> 
> Above notes that "simplification" is the primary motivation but I do not think
> this change qualifies as a "simplification". How about second paragraph changed
> to something like:
> 
> 	The io_alloc feature also uses CBMs to indicate which portions of
> 	cache are allocated for I/O traffic. The CBMs are provided by
> 	user space and need to be validated the same as CBMs provided for
> 	general (CPU) cache allocation. parse_cbm() cannot be used as-is
> 	since io_alloc does not have rdtgroup context.
> 
> 	Pass the mode and CLOSID directly to parse_cbm() via struct rdt_parse_data
> 	instead of through the rdtgroup struct to facilitate calling parse_cbm() to
> 	verify the CBM of the io_alloc feature.
> 
> (please feel free to improve)
> 

Looks good.

>>
>> Signed-off-by: Babu Moger <babu.moger@amd.com>
>> ---
> 
> 
> 
>> ---
>>  fs/resctrl/ctrlmondata.c | 29 +++++++++++++----------------
>>  fs/resctrl/internal.h    |  6 ++++++
>>  2 files changed, 19 insertions(+), 16 deletions(-)
>>
>> diff --git a/fs/resctrl/ctrlmondata.c b/fs/resctrl/ctrlmondata.c
>> index e78828b0408a..5c16557fb7a8 100644
>> --- a/fs/resctrl/ctrlmondata.c
>> +++ b/fs/resctrl/ctrlmondata.c
>> @@ -23,11 +23,6 @@
>>  
>>  #include "internal.h"
>>  
>> -struct rdt_parse_data {
>> -	struct rdtgroup		*rdtgrp;
>> -	char			*buf;
>> -};
>> -
> 
> This patch is only about replacing rdtgroup with mode and CLOSID, there is no
> motivation for relocating the structure declaration. This looks to be a change
> needed by following patch but is another change that becomes unnecessary if
> the io_alloc code, specifically resctrl_io_alloc_cbm_write() and
> resctrl_io_alloc_parse_line() from next patch, are moved to ctrlmondata.c.
> 

Yes. Not required to move now.

> ...
> 
>> @@ -171,7 +167,7 @@ static int parse_cbm(struct rdt_parse_data *data, struct resctrl_schema *s,
>>  	 * Cannot set up more than one pseudo-locked region in a cache
>>  	 * hierarchy.
>>  	 */
>> -	if (rdtgrp->mode == RDT_MODE_PSEUDO_LOCKSETUP &&
>> +	if (mode == RDT_MODE_PSEUDO_LOCKSETUP &&
>>  	    rdtgroup_pseudo_locked_in_hierarchy(d)) {
>>  		rdt_last_cmd_puts("Pseudo-locked region in hierarchy\n");
>>  		return -EINVAL;
>> @@ -180,9 +176,9 @@ static int parse_cbm(struct rdt_parse_data *data, struct resctrl_schema *s,
>>  	if (!cbm_validate(data->buf, &cbm_val, r))
>>  		return -EINVAL;
>>  
>> -	if ((rdtgrp->mode == RDT_MODE_EXCLUSIVE ||
>> -	     rdtgrp->mode == RDT_MODE_SHAREABLE) &&
>> -	    rdtgroup_cbm_overlaps_pseudo_locked(d, cbm_val)) {
>> +	if ((mode == RDT_MODE_EXCLUSIVE ||
>> +	     mode == RDT_MODE_SHAREABLE) &&
>> +	     rdtgroup_cbm_overlaps_pseudo_locked(d, cbm_val)) {
> 
> Please fix alignment.

Sure.

> 
>>  		rdt_last_cmd_puts("CBM overlaps with pseudo-locked region\n");
>>  		return -EINVAL;
>>  	}
> 
> Reinette
> 

-- 
Thanks
Babu Moger