Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752946AbZJUAEi (ORCPT ); Tue, 20 Oct 2009 20:04:38 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751825AbZJUAEi (ORCPT ); Tue, 20 Oct 2009 20:04:38 -0400 Received: from mx1.redhat.com ([209.132.183.28]:43082 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751689AbZJUAEh (ORCPT ); Tue, 20 Oct 2009 20:04:37 -0400 Message-ID: <4ADE5065.4040503@redhat.com> Date: Tue, 20 Oct 2009 20:05:57 -0400 From: Masami Hiramatsu User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.9.1.4pre) Gecko/20090922 Fedora/3.0-2.7.b4.fc11 Thunderbird/3.0b4 MIME-Version: 1.0 To: Ingo Molnar CC: Frederic Weisbecker , Steven Rostedt , lkml , Thomas Gleixner , Arnaldo Carvalho de Melo , Mike Galbraith , Paul Mackerras , Peter Zijlstra , Christoph Hellwig , Ananth N Mavinakayanahalli , Jim Keniston , "Frank Ch. Eigler" , "H. Peter Anvin" , systemtap , DLE Subject: Re: [PATCH -tip tracing/kprobes 0/9] tracing/kprobes, perf: perf probe and kprobe-tracer bugfixes References: <20091017000711.16556.69935.stgit@dhcp-100-2-132.bos.redhat.com> <20091017080203.GA4155@elte.hu> <20091017103427.GA31238@elte.hu> <4ADAAF50.9040604@redhat.com> <20091019075103.GF17960@elte.hu> <20091019110055.GA5549@nowhere> <20091019112125.GA12829@elte.hu> <4ADCC348.2020800@redhat.com> <4ADCEE1B.40003@redhat.com> <20091020065151.GM8550@elte.hu> In-Reply-To: <20091020065151.GM8550@elte.hu> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2043 Lines: 69 Ingo Molnar wrote: > * Masami Hiramatsu wrote: >> Masami Hiramatsu wrote: >>> Ingo Molnar wrote: >>>> For example you might want to probe the point within schedule that calls >>>> switch_mm() - this could be done via: >>>> >>>> perf probe schedule@switch_mm >>>> >>>> Or the point where 'next' gets assigned? Sure, you dont need to even >>>> open the editor, if you know the rough outline of the function you can >>>> probe it via: >>>> >>>> perf probe schedule@'next =' >>>> >>>> Note that i was able to specify both probes without having opened an >>>> editor - just based on the general knowledge of the scheduler. >>> >>> It may be useful for return probe too :-) >>> >>> perf probe schedule@return >> >> Hmm, IMHO, >> >>>> perf probe schedule@switch_mm >> >> might be confused as 'probe schedule() called from switch_mm()'. >> >> BTW, there might be several local/inline functions which have >> same name. >> I think we'd better provide a syntax for solving this issue. >> And current syntax uses @ for this purpose as below. >> >> perf probe localfunc@file >> >> Maybe, we still can use % for special matching, >> >> perf probe schedule%switch_mm >> >> These can be combined with each other, as below. >> >> perf probe schedule@kernel/sched.c%switch_mm >> >> Or, supporting lazy string pattern matching >> (reusing glob matching in ftrace?) >> >> perf probe schedule:'switch_mm(*);' >> >> Just my thought. > > I'm not attached to any particular form of syntax here (other than it > should be simple and obvious) - we can try and see how it works out. OK, so I'll try to implement it and see how it works out:-) -- Masami Hiramatsu Software Engineer Hitachi Computer Products (America), Inc. Software Solutions Division e-mail: mhiramat@redhat.com -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/