linux-kernel - Re: [PATCH v2 10/23] x86/resctrl: Remove architecture copy of mbps

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Message-ID: <c87201b6-2bad-4424-6280-5ee6ea47fea2@arm.com>
Date:   Wed, 27 Oct 2021 17:49:54 +0100
From:   James Morse <james.morse@....com>
To:     Reinette Chatre <reinette.chatre@...el.com>, x86@...nel.org,
        linux-kernel@...r.kernel.org
Cc:     Fenghua Yu <fenghua.yu@...el.com>,
        Thomas Gleixner <tglx@...utronix.de>,
        Ingo Molnar <mingo@...hat.com>, Borislav Petkov <bp@...en8.de>,
        H Peter Anvin <hpa@...or.com>,
        Babu Moger <Babu.Moger@....com>,
        shameerali.kolothum.thodi@...wei.com,
        Jamie Iles <jamie@...iainc.com>,
        D Scott Phillips OS <scott@...amperecomputing.com>,
        lcherian@...vell.com, bobo.shaobowang@...wei.com,
        tan.shaopeng@...itsu.com
Subject: Re: [PATCH v2 10/23] x86/resctrl: Remove architecture copy of
 mbps_val

Hi Reinette,

On 15/10/2021 23:27, Reinette Chatre wrote:
> On 10/1/2021 9:02 AM, James Morse wrote:
>> The resctrl arch code provides a second configuration array mbps_val[]
>> for the MBA software controller.
>>
>> Since resctrl switched over to allocating and freeing its own array
>> when needed, nothing uses the arch code version.
> 
> With the previous changes this is true, that this array is no longer used. Even so, the
> code removed in this patch is not just the usage of the array but also its management ...
> especially how and when it is reset. While the array is no longer used I think it is still
> important to ensure that all the array management is handled in the new mpbs_val array.
> Perhaps just help the reader by stating that the values of the new array never needs to be
> reset since it is always recreated while the previous array stuck around during umount/mount.

I've split those changes out as a separate patch which appears at the end of the series,
meaning the lifecycle stuff is unchanged by this point.


Thanks,

James