From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758190AbbAIPbI (ORCPT ); Fri, 9 Jan 2015 10:31:08 -0500 Received: from mx1.redhat.com ([209.132.183.28]:57952 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758174AbbAIPbG (ORCPT ); Fri, 9 Jan 2015 10:31:06 -0500 Date: Fri, 9 Jan 2015 16:30:56 +0100 From: Jiri Olsa To: Namhyung Kim Cc: Masami Hiramatsu , Arnaldo Carvalho de Melo , David Ahern , linux-kernel@vger.kernel.org Subject: Re: [BUG] perf probe can't insert return kprobe Message-ID: <20150109153056.GB4136@krava.brq.redhat.com> References: <20150109145539.GC14750@krava.brq.redhat.com> <20150109152113.GA29697@danjae> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20150109152113.GA29697@danjae> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sat, Jan 10, 2015 at 12:21:13AM +0900, Namhyung Kim wrote: > On Fri, Jan 09, 2015 at 03:55:39PM +0100, Jiri Olsa wrote: > > hi, > > I couldn't use following perf command to insert return probe: > > > > # perf probe -a fork_exit=do_fork%return > > Added new event: > > Failed to write event: Invalid argument > > Error: Failed to add events. > > > > > > I'm pretty sure I used this command before, so seems like > > it's broken. I can still use debugfs tracing interface to > > do that: > > # echo 'r:do_fork_entry do_fork' > kprobe_events > > > > I used Arnaldo's latest perf/core and FC20 kernel: > > > > # uname -a > > Linux krava 3.17.7-200.fc20.x86_64 #1 SMP Wed Dec 17 03:35:33 UTC 2014 x86_64 x86_64 x86_64 GNU/Linux > > # ./perf version > > perf version 3.18.g6a7d78 > > > > Is it just return probe? Did it work for normal kprobes? yep, works for normal probes > Maybe it's related to the below: > > https://lkml.org/lkml/2014/12/31/15 > > Have you check the acme/perf/urgent too? hum.. can't access lkml, I'll check, also with perf/urgent thanks, jirka