Re: [PATCH v11 06/23] x86/resctrl: Add support to enable/disable AMD ABMC feature

[James Morse]

Hi Babu,

On 22/01/2025 20:20, Babu Moger wrote:
> Add the functionality to enable/disable AMD ABMC feature.
> 
> AMD ABMC feature is enabled by setting enabled bit(0) in MSR
> L3_QOS_EXT_CFG. When the state of ABMC is changed, the MSR needs
> to be updated on all the logical processors in the QOS Domain.
> 
> Hardware counters will reset when ABMC state is changed.
> 
> The ABMC feature details are documented in APM listed below [1].
> [1] AMD64 Architecture Programmer's Manual Volume 2: System Programming
> Publication # 24593 Revision 3.41 section 19.3.3.3 Assignable Bandwidth
> Monitoring (ABMC).


> diff --git a/arch/x86/kernel/cpu/resctrl/internal.h b/arch/x86/kernel/cpu/resctrl/internal.h
> index 05358e78147b..ca69f2e0909f 100644
> --- a/arch/x86/kernel/cpu/resctrl/internal.h
> +++ b/arch/x86/kernel/cpu/resctrl/internal.h
> @@ -658,4 +663,6 @@ void resctrl_file_fflags_init(const char *config, unsigned long fflags);
>  void rdt_staged_configs_clear(void);
>  bool closid_allocated(unsigned int closid);
>  int resctrl_find_cleanest_closid(void);
> +int resctrl_arch_mbm_cntr_assign_set(struct rdt_resource *r, bool enable);
> +bool resctrl_arch_mbm_cntr_assign_enabled(struct rdt_resource *r);
>  #endif /* _ASM_X86_RESCTRL_INTERNAL_H */

A minor nit - but could these be added to include/linux/resctrl.h instead?
This is where they need to end up after the arch/fs split, and its harmless to do it from
the beginning.


Thanks,

James