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Date:   Tue, 20 Sep 2022 08:30:01 +0530
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Subject: Re: [PATCH v3 4/4] arm64: support batched/deferred tlb shootdown
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To:     Yicong Yang <yangyicong@huawei.com>, akpm@linux-foundation.org,
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References: <20220822082120.8347-1-yangyicong@huawei.com>
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On 8/22/22 13:51, Yicong Yang wrote:
> +static inline bool arch_tlbbatch_should_defer(struct mm_struct *mm)
> +{
> +	return true;
> +}

This needs to be conditional on systems, where there will be performance
improvements, and should not just be enabled all the time on all systems.
num_online_cpus() > X, which does not hold any cpu hotplug lock would be
a good metric ?