From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1762204AbZE1AdW (ORCPT ); Wed, 27 May 2009 20:33:22 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1755928AbZE1AdP (ORCPT ); Wed, 27 May 2009 20:33:15 -0400 Received: from mx1.redhat.com ([66.187.233.31]:39210 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754158AbZE1AdO (ORCPT ); Wed, 27 May 2009 20:33:14 -0400 MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit From: Roland McGrath To: Oleg Nesterov X-Fcc: ~/Mail/linus Cc: Christoph Hellwig , Ingo Molnar , linux-kernel@vger.kernel.org Subject: Re: [RFC PATCH 7/X] ptrace: mv task->parent ptrace_task->pt_tracer In-Reply-To: Oleg Nesterov's message of Thursday, 28 May 2009 01:59:36 +0200 <20090527235936.GB12216@redhat.com> References: <20090525000016.GA2239@redhat.com> <20090525215903.GA9113@redhat.com> <20090527021131.4778BFC36B@magilla.sf.frob.com> <20090527224140.GC6770@redhat.com> <20090527230700.11F2DFC2BD@magilla.sf.frob.com> <20090527235936.GB12216@redhat.com> X-Zippy-Says: Now, I think it would be GOOD to buy FIVE or SIX STUDEBAKERS and CRUISE for ARTIFICIAL FLAVORING!! Message-Id: <20090528003256.86E4EFC2BD@magilla.sf.frob.com> Date: Wed, 27 May 2009 17:32:56 -0700 (PDT) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > This is optimization. If exit_code == 0 we do not need to fixup > ->last_siginfo. Note that we have another "child->exit_code = exit_code" > below in the slow path. Ok, I see. > > It can check for !child->last_siginfo before lock_task_sighand(). > > ptrace_stop() always sets ->last_siginfo != NULL. Oh, right. It's only job control stops where it's NULL. > OK, lets do this change later ;) Agreed. Thanks, Roland