From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Date: Fri, 23 Feb 2018 08:53:17 -0800 From: Tejun Heo To: Eric Dumazet Cc: linux-kernel , netdev 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> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1519402362.55655.70.camel@gmail.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: On Fri, Feb 23, 2018 at 08:12:42AM -0800, Eric Dumazet wrote: > From: Eric Dumazet > > 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 Applied to percpu/for-4.16-fixes. Thank, Eric. -- tejun