From mboxrd@z Thu Jan 1 00:00:00 1970 From: Arnaldo Carvalho de Melo Subject: Re: [PATCH 3/3] perf events: add timehist option to record and report Date: Fri, 18 Feb 2011 17:06:06 -0200 Message-ID: <20110218190606.GD302@ghostprotocols.net> References: <1298008433-22911-1-git-send-email-daahern@cisco.com> <1298008433-22911-4-git-send-email-daahern@cisco.com> <20110218070657.GA11404@elte.hu> <4D5E8204.2090501@cisco.com> <20110218175926.GA3445@nowhere> <20110218184119.GC302@ghostprotocols.net> <4D5EC01C.1030108@cisco.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from mail-gy0-f174.google.com ([209.85.160.174]:47626 "EHLO mail-gy0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751458Ab1BRTGM (ORCPT ); Fri, 18 Feb 2011 14:06:12 -0500 Content-Disposition: inline In-Reply-To: <4D5EC01C.1030108@cisco.com> Sender: linux-perf-users-owner@vger.kernel.org List-ID: To: David Ahern Cc: Frederic Weisbecker , Ingo Molnar , linux-perf-users@vger.kernel.org, linux-kernel@vger.kernel.org, peterz@infradead.org, paulus@samba.org, Thomas Gleixner , Peter Zijlstra Em Fri, Feb 18, 2011 at 11:53:16AM -0700, David Ahern escreveu: > On 02/18/11 11:41, Arnaldo Carvalho de Melo wrote: > > Think about tcpdump + networking tracepoints or 'perf probe' dynamic > > events in the network stack, he wants to merge those logs and correlate > > the tcpdump packet exchange with the tracepoints events in the network > > stack, etc. > I'm zoned in on ap logs, but tcpdump and network analysis is another > very good example. packets are tagged with realtime: > static inline void __net_timestamp(struct sk_buff *skb) > { > skb->tstamp = ktime_get_real(); > } I'd bet the original intent was to merge that with app specific logs :-) Anyway, I think the way out of this is to have a clock_gettime like interface, let the users decide what they need (or think they do), sample it together with the other events and be done with it. - Arnaldo