Re: [PATCH v9 07/12] x86/resctrl: Add PMT registration API for AET enumeration callbacks

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

Hi Tony,

On 7/10/26 1:54 PM, Luck, Tony wrote:
> On Wed, Jul 08, 2026 at 03:51:22PM -0700, Reinette Chatre wrote:
>> On 7/1/26 2:35 PM, Tony Luck wrote:
>>> resctrl is always built-in; INTEL_PMT_TELEMETRY may be a module.  Add, and
>>> export, register/unregister functions so the PMT module can supply/clear
>>> enumeration callback functions when loaded/unloaded.
>>>
>>> Suggested-by: Christoph Hellwig <hch@infradead.org>
>>> Signed-off-by: Tony Luck <tony.luck@intel.com>
>>> ---
>>>  arch/x86/include/asm/resctrl.h          | 22 ++++++++++++++++
>>>  arch/x86/kernel/cpu/resctrl/intel_aet.c | 34 +++++++++++++++++++++++++
>>>  2 files changed, 56 insertions(+)
>>>
>>> diff --git a/arch/x86/include/asm/resctrl.h b/arch/x86/include/asm/resctrl.h
>>> index a9f481b7a8ed..48ad55bcda66 100644
>>> --- a/arch/x86/include/asm/resctrl.h
>>> +++ b/arch/x86/include/asm/resctrl.h
>>> @@ -4,6 +4,8 @@
>>>  
>>>  #ifdef CONFIG_X86_CPU_RESCTRL
>>>  
>>> +#include <linux/intel_pmt_features.h>
>>> +#include <linux/intel_vsec.h>
>>>  #include <linux/jump_label.h>
>>>  #include <linux/percpu.h>
>>>  #include <linux/resctrl_types.h>
>>> @@ -189,11 +191,31 @@ static inline void resctrl_arch_mon_ctx_free(struct rdt_resource *r,
>>>  
>>>  void resctrl_cpu_detect(struct cpuinfo_x86 *c);
>>>  
>>> +#ifdef CONFIG_X86_CPU_RESCTRL_INTEL_AET
>>> +void intel_aet_register_enumeration(struct module *module,
>>> +				    struct pmt_feature_group *(*get)(enum pmt_feature_id id),
>>> +				    void (*put)(struct pmt_feature_group *p));
>>> +void intel_aet_unregister_enumeration(void);
>>>  #else
>>> +static inline void intel_aet_register_enumeration(struct module *module,
>>> +						  struct pmt_feature_group *(*get)(enum pmt_feature_id id),
>>> +						  void (*put)(struct pmt_feature_group *p)) { }
>>> +static inline void intel_aet_unregister_enumeration(void) { }
>>> +#endif /* CONFIG_X86_CPU_RESCTRL_INTEL_AET */
>>> +
>>> +#else
>>> +
>>> +#include <linux/intel_pmt_features.h>
>>> +#include <linux/intel_vsec.h>
>>
>> Are we sure we want to include these in arch/x86/kernel/process_32.c and
>> arch/x86/kernel/process_64.c when resctrl is not built in?
> 
> I'll look at this some more. Maybe this code needs some X86_64 checks?
> 
Some forward declarations for the needed parameters may be simplest. Another
alternative may be for include/linux/resctrl.h to get a section for definitions
for when resctrl is not built in?

Reinette