From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752358AbZH0Pff (ORCPT ); Thu, 27 Aug 2009 11:35:35 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751627AbZH0Pfd (ORCPT ); Thu, 27 Aug 2009 11:35:33 -0400 Received: from mx1.redhat.com ([209.132.183.28]:37266 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751596AbZH0Pfc (ORCPT ); Thu, 27 Aug 2009 11:35:32 -0400 Message-ID: <4A96A865.1050300@redhat.com> Date: Thu, 27 Aug 2009 11:38:13 -0400 From: Masami Hiramatsu User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.9.1.1) Gecko/20090814 Fedora/3.0-2.6.b3.fc11 Thunderbird/3.0b3 MIME-Version: 1.0 To: Frederic Weisbecker CC: Ingo Molnar , LKML , Avi Kivity , Andi Kleen , Christoph Hellwig , "Frank Ch. Eigler" , "H. Peter Anvin" , Jason Baron , Jim Keniston , "K.Prasad" , Lai Jiangshan , Li Zefan , Przemys??aw Pawe??czyk , Roland McGrath , Sam Ravnborg , Srikar Dronamraju , Steven Rostedt , Tom Zanussi , Vegard Nossum Subject: Re: [PATCH 08/18] tracing: Add kprobe-based event tracer References: <1251340337-5640-1-git-send-email-fweisbec@gmail.com> <1251340337-5640-9-git-send-email-fweisbec@gmail.com> <20090827073139.GB2131@elte.hu> <20090827134800.GC6058@nowhere> In-Reply-To: <20090827134800.GC6058@nowhere> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Frederic Weisbecker wrote: > On Thu, Aug 27, 2009 at 09:31:39AM +0200, Ingo Molnar wrote: >> >> * Frederic Weisbecker wrote: >> >>> From: Masami Hiramatsu >>> >>> Add kprobes-based event tracer on ftrace. >>> >>> This tracer is similar to the events tracer which is based on >>> Tracepoint infrastructure. Instead of Tracepoint, this tracer is >>> based on kprobes (kprobe and kretprobe). It probes anywhere where >>> kprobes can probe(this >>> means, all functions body except for __kprobes functions). >>> >>> Similar to the events tracer, this tracer doesn't need to be >>> activated via current_tracer, instead of that, just set probe >>> points via /sys/kernel/debug/tracing/kprobe_events. And you can >>> set filters on each probe events via >>> /sys/kernel/debug/tracing/events/kprobes//filter. >> >> ok, one observation here: this should seemlessly merge into >> /debug/tracing/events/ and provide a record format descriptor in >> 'format' to allow the automated fetching of the results of the >> probe. The PERF_SAMPLE_RAW gateway should work as well. >> >> That way tooling that knows about /debug/tracing/events/ will >> automatically work with kprobes events as well. We can profile based >> on kprobes, etc. etc. >> >> The _setting_ of the probe is still a separate channel - but if >> existing installed probes are merged into existing tooling that's a >> big step forward in terms of utility. >> >> Ingo > > > It does already :) > > But I've split out this patch that initially embeded the documentation. > If you look at the 9/10 patch, you can see how look like the format > files for kprobes. As far as I've tested, it just requires two changes for perf-tools. - Support CONFIG_PROFILE_EVENT(profile_enable/disable) on kprobe-tracer. - Ignore 'alias' tag(which is a special tag in kprobes event) while parsing format file. Thank you, -- Masami Hiramatsu Software Engineer Hitachi Computer Products (America), Inc. Software Solutions Division e-mail: mhiramat@redhat.com