From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755192Ab0CDPzk (ORCPT ); Thu, 4 Mar 2010 10:55:40 -0500 Received: from hrndva-omtalb.mail.rr.com ([71.74.56.122]:62545 "EHLO hrndva-omtalb.mail.rr.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752153Ab0CDPzj (ORCPT ); Thu, 4 Mar 2010 10:55:39 -0500 X-Authority-Analysis: v=1.0 c=1 a=JmiDjSKT-SYA:10 a=7U3hwN5JcxgA:10 a=8d6VPHx2p93kJCR7aSwA:9 a=ienCycG46pfz8r4UL8YFLSoKL3gA:4 X-Cloudmark-Score: 0 X-Originating-IP: 74.67.89.75 Subject: Re: [RFC][PATCH 2/3] perf: Take a hot regs snapshot for trace events From: Steven Rostedt Reply-To: rostedt@goodmis.org To: Ingo Molnar Cc: Peter Zijlstra , Frederic Weisbecker , LKML , Thomas Gleixner , "H. Peter Anvin" , Paul Mackerras , Arnaldo Carvalho de Melo , Greg KH In-Reply-To: <20100304153606.GA32496@elte.hu> References: <1267599302-2886-1-git-send-regression-fweisbec@gmail.com> <1267599302-2886-3-git-send-regression-fweisbec@gmail.com> <1267632387.10871.59.camel@gandalf.stny.rr.com> <1267634258.25158.88.camel@laptop> <1267636046.10871.74.camel@gandalf.stny.rr.com> <1267636595.25158.93.camel@laptop> <20100304112531.GF21977@elte.hu> <1267715801.10871.191.camel@gandalf.stny.rr.com> <20100304153606.GA32496@elte.hu> Content-Type: text/plain; charset="ISO-8859-15" Organization: Kihon Technologies Inc. Date: Thu, 04 Mar 2010 10:55:31 -0500 Message-ID: <1267718131.10871.240.camel@gandalf.stny.rr.com> Mime-Version: 1.0 X-Mailer: Evolution 2.28.2 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 2010-03-04 at 16:36 +0100, Ingo Molnar wrote: > > This should be done anyway. But it would also let you decouple ftrace trace > > events from perf trace events but still let the two use the same trace > > points. > > I think the main thing would be to have a decoupled /eventfs - basically > /debug/tracing/events/ moved to "/eventfs" or maybe to "/proc/events/". This > would make them available more widely, and in a standardized way. I know Greg once proposed a /tracefs directory. I don't really care how things work as long as we don't lose functionality. Perhaps we should have a standard tracefs dir, and have: /sys/kernel/trace /sys/kernel/trace/events /sys/kernel/trace/ftrace /sys/kernel/trace/perf This would keep things nicely grouped but separate. I could also decouple the printing of the formats from ftrace.h and then in in the define_trace.h: #ifdef CONFIG_EVENTS # include # ifdef CONFIG_FTRACE_EVENTS # include # endif # ifdef CONFIG_PERF_EVENTS # include # endif #endif Have the trace/events.h file create the files for the event directory. But what about the enable and filter files in the event directory. How would they be attached? Currently these modify the way ftrace works. I'm assuming that perf enables these with the syscall. Should these files still be specific to ftrace if enabled? -- Steve