Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752189Ab3HZWIM (ORCPT ); Mon, 26 Aug 2013 18:08:12 -0400 Received: from mx1.redhat.com ([209.132.183.28]:8155 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751592Ab3HZWIL (ORCPT ); Mon, 26 Aug 2013 18:08:11 -0400 Date: Mon, 26 Aug 2013 18:07:11 -0400 From: Richard Guy Briggs To: Oleg Nesterov Cc: Peter Zijlstra , Eric Paris , linux-kernel@vger.kernel.org, linux-audit@redhat.com, Andrew Morton , Ingo Molnar , "Serge E. Hallyn" Subject: Re: [PATCH 11/12] pid: rewrite task helper functions avoiding task->pid and task->tgid Message-ID: <20130826220711.GA21098@madcap2.tricolour.ca> References: <20130822190848.GA25053@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20130822190848.GA25053@redhat.com> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1941 Lines: 68 On Thu, Aug 22, 2013 at 09:08:48PM +0200, Oleg Nesterov wrote: > On 08/20, Richard Guy Briggs wrote: > > > > static inline int is_global_init(struct task_struct *tsk) > > { > > - return tsk->pid == 1; > > + return task_pid_nr(tsk) == 1; > > } > > Probably it would be better to simply kill it. Almost every usage is > wrong. Can you be more clear? I don't follow. It should instead return a boolean. Usage of is_global_init() or task_pid_nr()? If is_global_init(), is that because they could be unaware of pid namespaces? If task_pid_nr(), is that for the same reason? > > static inline bool is_idle_task(const struct task_struct *p) > > { > > - return p->pid == 0; > > + return task_pid(p) == &init_struct_pid; > > } > > hmm. there should be a simpler check for this... Other than the original, this one is pretty simple. What did you have in mind? > > static inline int has_group_leader_pid(struct task_struct *p) > > { > > - return p->pid == p->tgid; > > + return task_pid(p) == task_tgid(p); > > } > > > > static inline > > int same_thread_group(struct task_struct *p1, struct task_struct *p2) > > { > > - return p1->tgid == p2->tgid; > > + return task_tgid(p1) == task_tgid(p2); > > This is suboptinal. See the attached > include-linux-schedh-dont-use-task-pid-tgid-in-same_thread_group-has_group_leader_pid.patch > from -mm below. I'm fine with that if it is deemed better. The point was to remove the dependence on task_struct::tgid. > Oleg. - RGB -- Richard Guy Briggs Senior Software Engineer Kernel Security AMER ENG Base Operating Systems Remote, Ottawa, Canada Voice: +1.647.777.2635 Internal: (81) 32635 Alt: +1.613.693.0684x3545 -- 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/