Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754141AbZCNDos (ORCPT ); Fri, 13 Mar 2009 23:44:48 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752487AbZCNDoj (ORCPT ); Fri, 13 Mar 2009 23:44:39 -0400 Received: from gate.crashing.org ([63.228.1.57]:43158 "EHLO gate.crashing.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751714AbZCNDoi (ORCPT ); Fri, 13 Mar 2009 23:44:38 -0400 Subject: Re: [patch 02/11] x86 architecture implementation of Hardware Breakpoint interfaces From: Benjamin Herrenschmidt To: Ingo Molnar Cc: Alan Stern , prasad@linux.vnet.ibm.com, Andrew Morton , Linux Kernel Mailing List , Roland McGrath In-Reply-To: <20090311121220.GI2282@elte.hu> References: <20090310172605.GA28767@elte.hu> <20090311121220.GI2282@elte.hu> Content-Type: text/plain Date: Sat, 14 Mar 2009 14:43:23 +1100 Message-Id: <1237002203.25062.80.camel@pasglop> Mime-Version: 1.0 X-Mailer: Evolution 2.24.3 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1232 Lines: 33 On Wed, 2009-03-11 at 13:12 +0100, Ingo Molnar wrote: > > #3 is probably the most informative (and hence probably the > best) variant. It also leaves policy of how to resolve the > conflict to the admin. Agreed. > > Would be nice to have it simple. Reluctance regarding this > patchset is mostly rooted in that diffstat above. > > The changes it does in the x86 architecture code are nice > generalizations and cleanups. Both the scheduler, task > startup/exit and ptrace bits look pretty sane in terms of > factoring out debug register details. But the breakpoint > management looks very complex I agree there is some interest in generalization and cleanup, especially as far as userspace APIs go, though it's a hard nut to crack as every CPU family out there has some subtle differences in the way breakpoints or watchpoints work (for example, alignment constraints, ability to do ranges, the way they handle kernel vs. user, etc...) I'm not yet sold. Cheers, Ben. -- 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/