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Date: Fri, 23 Feb 2018 08:53:17 -0800
From: Tejun Heo <tj@kernel.org>
To: Eric Dumazet <eric.dumazet@gmail.com>
Cc: linux-kernel <linux-kernel@vger.kernel.org>,
        netdev <netdev@vger.kernel.org>
Subject: Re: [PATCH] percpu: add a schedule point in pcpu_balance_workfn()
Message-ID: <20180223165317.GD1641506@devbig577.frc2.facebook.com>
References: <1519402362.55655.70.camel@gmail.com>
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On Fri, Feb 23, 2018 at 08:12:42AM -0800, Eric Dumazet wrote:
> From: Eric Dumazet <edumazet@google.com>
> 
> When a large BPF percpu map is destroyed, I have seen
> pcpu_balance_workfn() holding cpu for hundreds of milliseconds.
> 
> On KASAN config and 112 hyperthreads, average time to destroy a chunk
> is ~4 ms.
> 
> [ 2489.841376] destroy chunk 1 in 4148689 ns
> ...
> [ 2490.093428] destroy chunk 32 in 4072718 ns
> 
> Signed-off-by: Eric Dumazet <edumazet@google.com>

Applied to percpu/for-4.16-fixes.

Thank, Eric.

-- 
tejun