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Date:   Tue, 23 Feb 2021 13:33:28 -0800
From:   Martin KaFai Lau <kafai@fb.com>
To:     Song Liu <songliubraving@fb.com>
CC:     <bpf@vger.kernel.org>, <netdev@vger.kernel.org>,
        <linux-kernel@vger.kernel.org>, <ast@kernel.org>,
        <daniel@iogearbox.net>, <kernel-team@fb.com>,
        <peterz@infradead.org>, Andrii Nakryiko <andrii@kernel.org>
Subject: Re: [PATCH v4 bpf-next 6/6] bpf: runqslower: use task local storage
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On Mon, Feb 22, 2021 at 05:20:14PM -0800, Song Liu wrote:
> Replace hashtab with task local storage in runqslower. This improves the
> performance of these BPF programs. The following table summarizes average
> runtime of these programs, in nanoseconds:
> 
>                           task-local   hash-prealloc   hash-no-prealloc
> handle__sched_wakeup             125             340               3124
> handle__sched_wakeup_new        2812            1510               2998
> handle__sched_switch             151             208                991
Nice!  The required code change is also minimal.