Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1030511Ab2HPVlR (ORCPT ); Thu, 16 Aug 2012 17:41:17 -0400 Received: from mail.x86-64.org ([217.9.48.20]:53347 "EHLO mail.x86-64.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933430Ab2HPVlN (ORCPT ); Thu, 16 Aug 2012 17:41:13 -0400 Date: Thu, 16 Aug 2012 23:41:03 +0200 From: Borislav Petkov To: Steven Rostedt Cc: Jonathan Corbet , Peter Zijlstra , Ingo Molnar , Frederic Weisbecker , LKML Subject: Re: [RFC PATCH -v2 0/4] Persistent events Message-ID: <20120816214103.GE16308@aftab.osrc.amd.com> References: <1345139123-15212-1-git-send-email-bp@amd64.org> <20120816141253.0142ddd0@lwn.net> <20120816205539.GA16308@aftab.osrc.amd.com> <1345151613.3708.4.camel@gandalf.local.home> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1345151613.3708.4.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: 1367 Lines: 40 On Thu, Aug 16, 2012 at 05:13:33PM -0400, Steven Rostedt wrote: > BTW, we already have a persistent buffering in the kernel. It's used > by ftrace. What about having perf use that buffering for persistent > events? Or is there some other issues about using it. Not that I know of. I coded this with the perf ring buffer now. If only there was one ring buffer in the kernel.. /me ducks and hides. Ok, with perf I can read out the events programmatically by mmaping the per-CPU buffer with perf_mmap. How do you do that in ftrace? Any code pointers I can stare at? > I'm currently working on having perf read ftrace data, so in the near > future, I plan on having some RFC patches to have perf reading from > this buffer anyway. Are you saying the ftrace buffer would be mmappable too now? Btw, I wanted to hear your opinion on patch 1/4 since it touches ftrace/trace_events code. Can you please look at it and tell me if its ok? Thanks. -- 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/