From mboxrd@z Thu Jan 1 00:00:00 1970 From: Richard Cochran Subject: Re: [PATCH net-next] sock: don't enable netstamp for af_unix sockets Date: Tue, 27 Oct 2015 11:11:58 +0100 Message-ID: <20151027101157.GA1850@netboy> References: <1445863897-22646-1-git-send-email-hannes@stressinduktion.org> <20151026131928.GA1820@netboy> <1445866379.133031.420389177.3AE9E175@webmail.messagingengine.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: netdev@vger.kernel.org To: Hannes Frederic Sowa Return-path: Received: from mail-wi0-f178.google.com ([209.85.212.178]:38434 "EHLO mail-wi0-f178.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752229AbbJ0KMC (ORCPT ); Tue, 27 Oct 2015 06:12:02 -0400 Received: by wicll6 with SMTP id ll6so152577993wic.1 for ; Tue, 27 Oct 2015 03:12:01 -0700 (PDT) Content-Disposition: inline In-Reply-To: <1445866379.133031.420389177.3AE9E175@webmail.messagingengine.com> Sender: netdev-owner@vger.kernel.org List-ID: On Mon, Oct 26, 2015 at 02:32:59PM +0100, Hannes Frederic Sowa wrote: > On Mon, Oct 26, 2015, at 14:19, Richard Cochran wrote: > > On Mon, Oct 26, 2015 at 01:51:37PM +0100, Hannes Frederic Sowa wrote: > > > netstamp_needed is toggled for all socket families if they request > > > timestamping. But some protocols don't need the lower-layer timestamping > > > code at all. This patch starts disabling it for af-unix. > > > > What problem is this patch trying to solve? > > netstamp_needed is a static-key which enables timestamping code in the > networking stack receive functions for every packet, while it is not > needed for AF_UNIX/LOCAL. So it is merely a small performance > enhancement. Are there any numbers that show the effect of this enhancement? Thanks, Richard