Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751137AbVJXXDT (ORCPT ); Mon, 24 Oct 2005 19:03:19 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751350AbVJXXDT (ORCPT ); Mon, 24 Oct 2005 19:03:19 -0400 Received: from e33.co.us.ibm.com ([32.97.110.151]:17889 "EHLO e33.co.us.ibm.com") by vger.kernel.org with ESMTP id S1751137AbVJXXDT (ORCPT ); Mon, 24 Oct 2005 19:03:19 -0400 Date: Mon, 24 Oct 2005 16:03:57 -0700 From: "Paul E. McKenney" To: Badari Pulavarty Cc: Kyle Moffett , Andrew Morton , Ingo Oeser , lkml , arjan@infradead.org, pavel@ucw.cz, dipankar@in.ibm.com, vatsa@in.ibm.com, rusty@au1.ib.com, mingo@elte.hu, manfred@colorfullife.com, gregkh@kroah.com Subject: Re: [PATCH] RCU torture-testing kernel module Message-ID: <20051024230357.GG12812@us.ibm.com> Reply-To: paulmck@us.ibm.com References: <20051022231214.GA5847@us.ibm.com> <200510230922.26550.ioe-lkml@rameria.de> <20051023143617.GA7961@us.ibm.com> <200510232055.17782.ioe-lkml@rameria.de> <20051023120521.26031051.akpm@osdl.org> <20051024004709.GA9454@us.ibm.com> <1130171073.6831.6.camel@localhost.localdomain> <5D5AD6EA-5D6E-47DA-8170-0729F9C32889@mac.com> <1130177458.6831.11.camel@localhost.localdomain> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1130177458.6831.11.camel@localhost.localdomain> User-Agent: Mutt/1.4.1i Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1752 Lines: 39 On Mon, Oct 24, 2005 at 11:10:58AM -0700, Badari Pulavarty wrote: > On Mon, 2005-10-24 at 13:59 -0400, Kyle Moffett wrote: > > On Oct 24, 2005, at 12:24:33, Badari Pulavarty wrote: > > > Paul, > > > > > > I enabled RCU_TORTURE_TEST in 2.6.14-rc5-mm1. My machine took 10+ > > > minutes to boot and let me login. RCU kthreads are hogging the > > > CPU. Is this expected ? > > > > Uhh... It's a torture test. What exactly do _you_ expect it will > > do? I think the idea is to enable it as a module and load it when > > you want to start torture testing, and unload it when done. > > "TORTURE_TEST"s are not for production systems :-D. Hey, and if you think that is fun, just try compiling it in (CONFIG_RCU_TORTURE_TEST=y) and then build rcutorture.c as an external module, then insmod'ing it! You get two torture tests running concurrently. I found this out the hard way while learning how the "tristate" directive works. > I was expecting that - even if its compiled in, there would be > a way to turn on/off the tests from /proc or something :) Well, I submitted -that- patch a couple of weeks ago, and it was roundly denounced for /proc pollution, hence the shiny new modules implementation of it. I must admit I was rather negative on the idea of using modules for this sort of thing, but after actually trying it, I found that it really works quite nicely. The module loader even parses all your arguments for you, so you can very easily parameterize the tests. Thanx, Paul - 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/