From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andi Kleen Date: Mon, 17 Apr 2006 17:10:46 +0000 Subject: Re: [PATCH 00/05] robust per_cpu allocation for modules Message-Id: <200604171910.48838.ak@suse.de> List-Id: References: <1145049535.1336.128.camel@localhost.localdomain> <4441ECE6.5010709@yahoo.com.au> In-Reply-To: <4441ECE6.5010709@yahoo.com.au> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Nick Piggin Cc: Steven Rostedt , LKML , Andrew Morton , Linus Torvalds , Ingo Molnar , Thomas Gleixner , Martin Mares , bjornw@axis.com, schwidefsky@de.ibm.com, benedict.gaster@superh.com, lethal@linux-sh.org, Chris Zankel , Marc Gauthier , Joe Taylor , David Mosberger-Tang , rth@twiddle.net, spyro@f2s.com, starvik@axis.com, tony.luck@intel.com, linux-ia64@vger.kernel.org, ralf@linux-mips.org, linux-mips@linux-mips.org, grundler@parisc-linux.org, parisc-linux@parisc-linux.org, linuxppc-dev@ozlabs.org, paulus@samba.org, linux390@de.ibm.com, davem@davemloft.net On Sunday 16 April 2006 09:06, Nick Piggin wrote: > I still don't understand what the justification is for slowing down > this critical bit of infrastructure for something that is only a > problem in the -rt patchset, and even then only a problem when tracing > is enabled. There are actually problems outside -rt. e.g. the Xen kernel was running into a near overflow and as more and more code is using per cpu variables others might too. I'm confident the problem can be solved without adding more variables though - e.g. in the way rusty proposed. -Andi From mboxrd@z Thu Jan 1 00:00:00 1970 Received: with ECARTIS (v1.0.0; list linux-mips); Mon, 17 Apr 2006 17:59:33 +0100 (BST) Received: from mx2.suse.de ([195.135.220.15]:53168 "HELO mx2.suse.de") by ftp.linux-mips.org with SMTP id S8133415AbWDQQ7X (ORCPT ); Mon, 17 Apr 2006 17:59:23 +0100 Received: from Relay1.suse.de (mail2.suse.de [195.135.221.8]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by mx2.suse.de (Postfix) with ESMTP id CC1C81EBCD; Mon, 17 Apr 2006 19:11:36 +0200 (CEST) From: Andi Kleen To: Nick Piggin Subject: Re: [PATCH 00/05] robust per_cpu allocation for modules Date: Mon, 17 Apr 2006 19:10:46 +0200 User-Agent: KMail/1.9.1 Cc: Steven Rostedt , LKML , Andrew Morton , Linus Torvalds , Ingo Molnar , Thomas Gleixner , Martin Mares , bjornw@axis.com, schwidefsky@de.ibm.com, benedict.gaster@superh.com, lethal@linux-sh.org, Chris Zankel , Marc Gauthier , Joe Taylor , David Mosberger-Tang , rth@twiddle.net, spyro@f2s.com, starvik@axis.com, tony.luck@intel.com, linux-ia64@vger.kernel.org, ralf@linux-mips.org, linux-mips@linux-mips.org, grundler@parisc-linux.org, parisc-linux@parisc-linux.org, linuxppc-dev@ozlabs.org, paulus@samba.org, linux390@de.ibm.com, davem@davemloft.net References: <1145049535.1336.128.camel@localhost.localdomain> <4441ECE6.5010709@yahoo.com.au> In-Reply-To: <4441ECE6.5010709@yahoo.com.au> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200604171910.48838.ak@suse.de> Return-Path: X-Envelope-To: <"|/home/ecartis/ecartis -s linux-mips"> (uid 0) X-Orcpt: rfc822;linux-mips@linux-mips.org Original-Recipient: rfc822;linux-mips@linux-mips.org X-archive-position: 11144 X-ecartis-version: Ecartis v1.0.0 Sender: linux-mips-bounce@linux-mips.org Errors-to: linux-mips-bounce@linux-mips.org X-original-sender: ak@suse.de Precedence: bulk X-list: linux-mips On Sunday 16 April 2006 09:06, Nick Piggin wrote: > I still don't understand what the justification is for slowing down > this critical bit of infrastructure for something that is only a > problem in the -rt patchset, and even then only a problem when tracing > is enabled. There are actually problems outside -rt. e.g. the Xen kernel was running into a near overflow and as more and more code is using per cpu variables others might too. I'm confident the problem can be solved without adding more variables though - e.g. in the way rusty proposed. -Andi From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx2.suse.de (mx2.suse.de [195.135.220.15]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client CN "mx2.suse.de", Issuer "Thawte Premium Server CA" (verified OK)) by ozlabs.org (Postfix) with ESMTP id BBEBF67A5D for ; Tue, 18 Apr 2006 03:11:44 +1000 (EST) From: Andi Kleen To: Nick Piggin Subject: Re: [PATCH 00/05] robust per_cpu allocation for modules Date: Mon, 17 Apr 2006 19:10:46 +0200 References: <1145049535.1336.128.camel@localhost.localdomain> <4441ECE6.5010709@yahoo.com.au> In-Reply-To: <4441ECE6.5010709@yahoo.com.au> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Message-Id: <200604171910.48838.ak@suse.de> Cc: Andrew Morton , linux-mips@linux-mips.org, David Mosberger-Tang , linux-ia64@vger.kernel.org, Martin Mares , spyro@f2s.com, Joe Taylor , linuxppc-dev@ozlabs.org, paulus@samba.org, benedict.gaster@superh.com, bjornw@axis.com, Ingo Molnar , grundler@parisc-linux.org, Steven Rostedt , starvik@axis.com, Linus Torvalds , Thomas Gleixner , rth@twiddle.net, Chris Zankel , tony.luck@intel.com, LKML , ralf@linux-mips.org, Marc Gauthier , lethal@linux-sh.org, schwidefsky@de.ibm.com, linux390@de.ibm.com, davem@davemloft.net, parisc-linux@parisc-linux.org List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Sunday 16 April 2006 09:06, Nick Piggin wrote: > I still don't understand what the justification is for slowing down > this critical bit of infrastructure for something that is only a > problem in the -rt patchset, and even then only a problem when tracing > is enabled. There are actually problems outside -rt. e.g. the Xen kernel was running into a near overflow and as more and more code is using per cpu variables others might too. I'm confident the problem can be solved without adding more variables though - e.g. in the way rusty proposed. -Andi