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References: <20230525180209.19497-1-james.morse@arm.com> <20230525180209.19497-13-james.morse@arm.com>
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From:   Peter Newman <peternewman@google.com>
Date:   Thu, 8 Jun 2023 10:53:47 +0200
Message-ID: <CALPaoCj3h=ELzRwUB2FcPAFAMD7G_nq1-r=PUGOuLq38bUMr0g@mail.gmail.com>
Subject: Re: [PATCH v4 12/24] x86/resctrl: Make resctrl_arch_rmid_read() retry
 when it is interrupted
To:     James Morse <james.morse@arm.com>
Cc:     x86@kernel.org, linux-kernel@vger.kernel.org,
        Fenghua Yu <fenghua.yu@intel.com>,
        Reinette Chatre <reinette.chatre@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>,
        shameerali.kolothum.thodi@huawei.com,
        D Scott Phillips OS <scott@os.amperecomputing.com>,
        carl@os.amperecomputing.com, lcherian@marvell.com,
        bobo.shaobowang@huawei.com, tan.shaopeng@fujitsu.com,
        xingxin.hx@openanolis.org, baolin.wang@linux.alibaba.com,
        Jamie Iles <quic_jiles@quicinc.com>,
        Xin Hao <xhao@linux.alibaba.com>, dfustini@baylibre.com
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Hi James,

On Thu, May 25, 2023 at 8:03=E2=80=AFPM James Morse <james.morse@arm.com> w=
rote:
>
> resctrl_arch_rmid_read() could be called by resctrl in process context,
> and then called by the PMU driver from irq context on the same CPU.

Will there be x86 PMU changes to do this or is this only ARM? I just
want to make sure the x86 resctrl_arch_rmid_read() changes are
actually needed.

Thanks!
-Peter