From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1762068AbYDSVF0 (ORCPT ); Sat, 19 Apr 2008 17:05:26 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1756515AbYDSVFO (ORCPT ); Sat, 19 Apr 2008 17:05:14 -0400 Received: from tomts43-srv.bellnexxia.net ([209.226.175.110]:42712 "EHLO tomts43-srv.bellnexxia.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756107AbYDSVFM (ORCPT ); Sat, 19 Apr 2008 17:05:12 -0400 X-IronPort-Anti-Spam-Filtered: true X-IronPort-Anti-Spam-Result: At0FAB/7CUhMROPA/2dsb2JhbACBYKh3 Date: Sat, 19 Apr 2008 17:00:10 -0400 From: Mathieu Desnoyers To: Andi Kleen Cc: mingo@elte.hu, akpm@osdl.org, "H. Peter Anvin" , Jeremy Fitzhardinge , Steven Rostedt , "Frank Ch. Eigler" , linux-kernel@vger.kernel.org Subject: Re: [RFC PATCH] x86 NMI-safe INT3 and Page Fault (v5) Message-ID: <20080419210010.GB1554@Krystal> References: <20080417165839.GA25198@Krystal> <20080417165944.GB25198@Krystal> <20080417201410.GB31616@Krystal> <87od889m44.fsf@basil.nowhere.org> <20080418000634.GB5062@Krystal> <480856BD.3080903@firstfloor.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline In-Reply-To: <480856BD.3080903@firstfloor.org> X-Editor: vi X-Info: http://krystal.dyndns.org:8080 X-Operating-System: Linux/2.6.21.3-grsec (i686) X-Uptime: 16:58:38 up 50 days, 17:09, 4 users, load average: 0.23, 0.31, 0.30 User-Agent: Mutt/1.5.16 (2007-06-11) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org * Andi Kleen (andi@firstfloor.org) wrote: > Mathieu Desnoyers wrote: > > * Andi Kleen (andi@firstfloor.org) wrote: > >> Mathieu Desnoyers writes: > >>> It allows placing immediate values (and therefore optimized trace_marks) in NMI > >>> code > >> Only if all your trace_mark infrastructure is lock less. > >> > >> -Andi > >> > > > > It uses RCU-style updates and has been designed to be lockless from the > > ground up. > > Wrong. If it causes vmalloc faults it is not lockless. > > -Andi > Could you point me where vmalloc_fault accesses a data structure for which updates are protected by disabling interrupts ? I am curious. Mathieu -- Mathieu Desnoyers Computer Engineering Ph.D. Student, Ecole Polytechnique de Montreal OpenPGP key fingerprint: 8CD5 52C3 8E3C 4140 715F BA06 3F25 A8FE 3BAE 9A68