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Date:   Thu, 14 Dec 2023 11:38:28 +0000
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Subject: Re: [PATCH v7 21/24] x86/resctrl: Allow overflow/limbo handlers to be
 scheduled on any-but cpu
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To:     babu.moger@amd.com, x86@kernel.org, linux-kernel@vger.kernel.org
Cc:     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>,
        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,
        baolin.wang@linux.alibaba.com, Jamie Iles <quic_jiles@quicinc.com>,
        Xin Hao <xhao@linux.alibaba.com>, peternewman@google.com,
        dfustini@baylibre.com, amitsinght@marvell.com
References: <20231025180345.28061-1-james.morse@arm.com>
 <20231025180345.28061-22-james.morse@arm.com>
 <6f90a9c6-d474-4173-9f74-a51675b10e6f@amd.com>
From:   James Morse <james.morse@arm.com>
In-Reply-To: <6f90a9c6-d474-4173-9f74-a51675b10e6f@amd.com>
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Hi Babu,

On 09/11/2023 20:51, Moger, Babu wrote:
> On 10/25/23 13:03, James Morse wrote:
>> When a CPU is taken offline resctrl may need to move the overflow or
>> limbo handlers to run on a different CPU.
>>
>> Once the offline callbacks have been split, cqm_setup_limbo_handler()
>> will be called while the CPU that is going offline is still present
>> in the cpu_mask.
>>
>> Pass the CPU to exclude to cqm_setup_limbo_handler() and
>> mbm_setup_overflow_handler(). These functions can use a variant of
>> cpumask_any_but() when selecting the CPU. -1 is used to indicate no CPUs
>> need excluding.
>>
>> A subsequent patch moves these calls to be before CPUs have been removed,
>> so this exclude_cpus behaviour is temporary.

> Reviewed-by: Babu Moger <babu.moger@amd.com>

Thanks!


James