From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751869AbbJNFOq (ORCPT ); Wed, 14 Oct 2015 01:14:46 -0400 Received: from mail-pa0-f45.google.com ([209.85.220.45]:36574 "EHLO mail-pa0-f45.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750807AbbJNFOm (ORCPT ); Wed, 14 Oct 2015 01:14:42 -0400 Subject: Re: [RFC PATCH 2/2] bpf: Implement bpf_perf_event_sample_enable/disable() helpers To: He Kuang , "Wangnan (F)" , Kaixu Xia , davem@davemloft.net, acme@kernel.org, mingo@redhat.com, a.p.zijlstra@chello.nl, masami.hiramatsu.pt@hitachi.com, jolsa@kernel.org, daniel@iogearbox.net References: <1444640563-159175-1-git-send-email-xiakaixu@huawei.com> <1444640563-159175-3-git-send-email-xiakaixu@huawei.com> <561C0A1E.2080500@plumgrid.com> <561C7A1F.6040702@huawei.com> <561C7CDA.8050004@plumgrid.com> <561C7FBE.4000104@huawei.com> <561C85BB.3000505@plumgrid.com> <561C89EC.8030303@huawei.com> <561C9361.6090104@plumgrid.com> <561CE2DB.2030409@huawei.com> Cc: linux-kernel@vger.kernel.org, pi3orama@163.com, netdev@vger.kernel.org From: Alexei Starovoitov Message-ID: <561DE4BF.6090306@plumgrid.com> Date: Tue, 13 Oct 2015 22:14:39 -0700 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.10; rv:38.0) Gecko/20100101 Thunderbird/38.3.0 MIME-Version: 1.0 In-Reply-To: <561CE2DB.2030409@huawei.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 10/13/15 3:54 AM, He Kuang wrote: > If we want perf to reflect as soon as our sample event be generated, > --no-buffering should be used, but this option has a greater > impact on performance. no_buffering doesn't have to be applied to all events obviously.