From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Ahern Subject: Re: [PATCH net-next] ipv6: let trace_fib6_table_lookup() dereference the fib table Date: Thu, 19 Oct 2017 09:38:27 -0600 Message-ID: <5462ed72-5180-3e10-c5d9-37762207653f@cumulusnetworks.com> References: <48235df8fdf787356070d8baa1ac9816ef5736d4.1508398120.git.pabeni@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Cc: "David S. Miller" , Steven Rostedt , Ingo Molnar To: Paolo Abeni , netdev@vger.kernel.org Return-path: Received: from mail-pf0-f194.google.com ([209.85.192.194]:44159 "EHLO mail-pf0-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752586AbdJSPi3 (ORCPT ); Thu, 19 Oct 2017 11:38:29 -0400 Received: by mail-pf0-f194.google.com with SMTP id x7so6851317pfa.1 for ; Thu, 19 Oct 2017 08:38:29 -0700 (PDT) In-Reply-To: <48235df8fdf787356070d8baa1ac9816ef5736d4.1508398120.git.pabeni@redhat.com> Content-Language: en-US Sender: netdev-owner@vger.kernel.org List-ID: On 10/19/17 1:31 AM, Paolo Abeni wrote: > The perf traces for ipv6 routing code show a relevant cost around > trace_fib6_table_lookup(), even if no trace is enabled. This is > due to the fib6_table de-referencing currently performed by the > caller. > > Let's the tracing code pay this overhead, passing to the trace > helper the table pointer. This gives small but measurable > performance improvement under UDP flood. > > Signed-off-by: Paolo Abeni > --- > include/trace/events/fib6.h | 6 +++--- > net/ipv6/route.c | 12 ++++++------ > 2 files changed, 9 insertions(+), 9 deletions(-) Makes sense. Acked-by: David Ahern