Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755095Ab2HQH0Y (ORCPT ); Fri, 17 Aug 2012 03:26:24 -0400 Received: from mail.x86-64.org ([217.9.48.20]:55151 "EHLO mail.x86-64.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751642Ab2HQH0W (ORCPT ); Fri, 17 Aug 2012 03:26:22 -0400 Date: Fri, 17 Aug 2012 09:26:13 +0200 From: Borislav Petkov To: Steven Rostedt Cc: Peter Zijlstra , Ingo Molnar , Frederic Weisbecker , LKML , Borislav Petkov Subject: Re: [RFC PATCH -v2 1/4] trace events: Interface to add files to debugfs Message-ID: <20120817072613.GA20591@aftab.osrc.amd.com> References: <1345139123-15212-1-git-send-email-bp@amd64.org> <1345139123-15212-2-git-send-email-bp@amd64.org> <1345154808.3708.15.camel@gandalf.local.home> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1345154808.3708.15.camel@gandalf.local.home> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1404 Lines: 45 On Thu, Aug 16, 2012 at 06:06:48PM -0400, Steven Rostedt wrote: > > /mnt/dbg/tracing/events/mce/mce_record/ > > |-- enable > > |-- filter > > |-- format > > |-- id > > `-- persistent > > This looks rather hacky :-/ Ya think?! :-) Well, this whole machinery is only for telling to userspace which is the file descriptor of the persistent event. And yes, it could probably be done with a lot less code. Hell, I'm even fine with issuing it in dmesg and userspace parsing the output - talk about efficient implementation. > Can't this be added to the perf syscall, and have the user query the > event instead? Do you mean perf_ioctl? For that to work I need to have a file descriptor of the "normal" event first and then query it to get the persistent file descriptor... Or do you mean something easier? > Note, this code will change drastically soon, and this change will > break. I'll talk more about what will change at plumbers. I'll try to get a video or something... :) -- Regards/Gruss, Boris. Advanced Micro Devices GmbH Einsteinring 24, 85609 Dornach GM: Alberto Bozzo Reg: Dornach, Landkreis Muenchen HRB Nr. 43632 WEEE Registernr: 129 19551 -- 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/