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Subject: Re: [PATCH v3 07/10] x86/resctrl: Add arch_needs_linear to explain
 AMD/Intel MBA difference
To:     James Morse <james.morse@arm.com>, x86@kernel.org,
        linux-kernel@vger.kernel.org
Cc:     Fenghua Yu <fenghua.yu@intel.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
        H Peter Anvin <hpa@zytor.com>,
        Babu Moger <Babu.Moger@amd.com>
References: <20200518131924.7741-1-james.morse@arm.com>
 <20200518131924.7741-8-james.morse@arm.com>
From:   Reinette Chatre <reinette.chatre@intel.com>
Message-ID: <ff095b21-023c-a3c6-2f6c-89c0e3d02eb3@intel.com>
Date:   Tue, 19 May 2020 11:03:14 -0700
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Hi James,

On 5/18/2020 6:19 AM, James Morse wrote:
> diff --git a/arch/x86/kernel/cpu/resctrl/internal.h b/arch/x86/kernel/cpu/resctrl/internal.h
> index dd51e23e346b..0b288b6fefd9 100644
> --- a/arch/x86/kernel/cpu/resctrl/internal.h
> +++ b/arch/x86/kernel/cpu/resctrl/internal.h
> @@ -370,6 +370,7 @@ struct rdt_cache {
>   * struct rdt_membw - Memory bandwidth allocation related data
>   * @min_bw:		Minimum memory bandwidth percentage user can request
>   * @bw_gran:		Granularity at which the memory bandwidth is allocated
> + * @arch_needs_linear:	True if we can't configure non-linear resources
>   * @delay_linear:	True if memory B/W delay is in linear scale
>   * @mba_sc:		True if MBA software controller(mba_sc) is enabled
>   * @mb_map:		Mapping of memory B/W percentage to memory B/W delay
> @@ -378,6 +379,7 @@ struct rdt_membw {
>  	u32		min_bw;
>  	u32		bw_gran;
>  	u32		delay_linear;
> +	bool		arch_needs_linear;
>  	bool		mba_sc;
>  	u32		*mb_map;
>  };
> 

Sorry, I just noticed this while rebasing our respective changes to this
area ... could the comments be in the same order as the fields in the
struct?

Reinette