Re: [PATCH v2 09/14] fs/resctrl: Add last_cmd_status support for writes to max_threshold_occupancy

[Reinette Chatre <reinette.chatre@intel.com>]

Hi Chenyu,

On 3/23/26 2:14 AM, Chen, Yu C wrote:
> On 3/21/2026 6:03 AM, Reinette Chatre wrote:
>> info/last_cmd_status is intended to contain more information if a write to
>> any resctrl file fails. Writes to max_threshold_occupancy did not receive
>> last_cmd_status support during initial last_cmd_status enabling. Add it now.
>>
>> Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
>> Reviewed-by: Ben Horgan <ben.horgan@arm.com>
>> ---
>> Changes since v1:
>> - Add Ben's RB tag.
>> ---
>>   fs/resctrl/rdtgroup.c | 21 ++++++++++++++++-----
>>   1 file changed, 16 insertions(+), 5 deletions(-)
>>
>> diff --git a/fs/resctrl/rdtgroup.c b/fs/resctrl/rdtgroup.c
>> index 111bff8e33fd..6fa5c8f14e3a 100644
>> --- a/fs/resctrl/rdtgroup.c
>> +++ b/fs/resctrl/rdtgroup.c
>> @@ -1238,16 +1238,27 @@ static ssize_t max_threshold_occ_write(struct kernfs_open_file *of,
>>       unsigned int bytes;
>>       int ret;
>>   +    mutex_lock(&rdtgroup_mutex);
> 
> Maybe guard(mutex)(&rdtgroup_mutex) and return ret when failed
> so we can get rid of goto out_unlock

Will do. There is no plan to switch existing patterns to use guard(), but using it in
cases like this where it is a new introduction to a function that does not already
use goto should be fine.

Reinette