From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752277AbZD2GD5 (ORCPT ); Wed, 29 Apr 2009 02:03:57 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751379AbZD2GDo (ORCPT ); Wed, 29 Apr 2009 02:03:44 -0400 Received: from mx2.mail.elte.hu ([157.181.151.9]:37196 "EHLO mx2.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751296AbZD2GDo (ORCPT ); Wed, 29 Apr 2009 02:03:44 -0400 Date: Wed, 29 Apr 2009 08:03:26 +0200 From: Ingo Molnar To: Steven Rostedt Cc: linux-kernel@vger.kernel.org, Andrew Morton , Frederic Weisbecker Subject: Re: [PATCH 0/5] [GIT PULL] tracing/splice/ringbuffer: updates for tip Message-ID: <20090429060326.GC6148@elte.hu> References: <20090429044814.138790038@goodmis.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20090429044814.138790038@goodmis.org> User-Agent: Mutt/1.5.18 (2008-05-17) X-ELTE-VirusStatus: clean X-ELTE-SpamScore: -1.5 X-ELTE-SpamLevel: X-ELTE-SpamCheck: no X-ELTE-SpamVersion: ELTE 2.0 X-ELTE-SpamCheck-Details: score=-1.5 required=5.9 tests=BAYES_00 autolearn=no SpamAssassin version=3.2.3 -1.5 BAYES_00 BODY: Bayesian spam probability is 0 to 1% [score: 0.0000] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org * Steven Rostedt wrote: > Ingo, > > I was doing a bit of tracing that was stressing the splice code > and I found lots of badness. Mostly, the second patch is the > killer, and should most likely go upstream ASAP. The ref counting > on the splice page is wrong and is never freed! ah, this probably explains what i reported some time ago: the ftrace-analyzer OOM hang. I've cherry-picked this into tracing/urgent as well. > The rest are fixes to the read side. While debugging the memory > leak I pulled out my old logdev and used it to monitor what was > happening inside of ftrace (tracing the tracer). I did not like > the amount of copying that was happening in splice. This was > mainly because splice was faster than the writer (and this was > with function tracer running!). I added some enhancements to make > the splice code perform a little nicer. > > Here's the logdev patch I was using to trace. As well as adding my > lfcnprint statements (similar to trace_printk). > > http://rostedt.homelinux.com/logdev/logdev-0.6.0-2.6.30-rc1.patch > > Please pull the latest tip/tracing/ftrace-1 tree, which can be > found at: > > git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-2.6-trace.git > tip/tracing/ftrace-1 > > > Steven Rostedt (5): > tracing: convert ftrace_dump spinlocks to raw > tracing: fix ref count in splice pages > tracing: only add splice page if entries exist > tracing: have splice only copy full pages > ring-buffer: fix printk output > > ---- > kernel/trace/ring_buffer.c | 2 +- > kernel/trace/trace.c | 20 ++++++++++++++------ > 2 files changed, 15 insertions(+), 7 deletions(-) Pulled, thanks a lot Steve! Ingo