Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759107Ab1FWJOI (ORCPT ); Thu, 23 Jun 2011 05:14:08 -0400 Received: from mail-bw0-f46.google.com ([209.85.214.46]:53826 "EHLO mail-bw0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758983Ab1FWJOF (ORCPT ); Thu, 23 Jun 2011 05:14:05 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=sender:date:from:to:cc:subject:message-id:references:mime-version :content-type:content-disposition:in-reply-to:user-agent; b=EkwjsRR1NmrApOWTnuQlNeJfu5r5+nsly61MjuRiwyk8AXmw3Yg+nd651VIOsaoimm 58c4uGne3eGnh3cthXs6u//VFVQSRnYPlclyVeRBD7Sw0rXL3XCyPO+BD2ww9kG3F4Uz m/buyVE8HfYMez5+CXJ2FQOv43AeuMTOmaz+8= Date: Thu, 23 Jun 2011 11:14:00 +0200 From: Tejun Heo To: Oleg Nesterov Cc: linux-kernel@vger.kernel.org, akpm@linux-foundation.org, torvalds@linux-foundation.org, hch@infradead.org, John Johansen , Stephen Smalley Subject: Re: [PATCH 7/7] ptrace: s/tracehook_tracer_task()/ptrace_parent()/ Message-ID: <20110623091400.GH30101@htj.dyndns.org> References: <1308322240-8247-1-git-send-email-tj@kernel.org> <1308322240-8247-8-git-send-email-tj@kernel.org> <20110620201603.GA17157@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20110620201603.GA17157@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: 1713 Lines: 50 Hello, On Mon, Jun 20, 2011 at 10:16:03PM +0200, Oleg Nesterov wrote: > On 06/17, Tejun Heo wrote: > > > > tracehook.h is on the way out. Rename tracehook_tracer_task() to > > ptrace_parent() and move it from tracehook.h to ptrace.h. > > I am a bit surpised you decided to keep this helper. Can't we simply > kill it? I was being a bit lazy. If it can be killed, it would be great. > OK, we will see. I guess this change is mostly needed to remove yet > another function from tracehook.h. > > > @@ -216,7 +216,7 @@ static struct mm_struct *__check_mem_permission(struct task_struct *task) > > if (task_is_stopped_or_traced(task)) { > > int match; > > rcu_read_lock(); > > - match = (tracehook_tracer_task(task) == current); > > + match = (ptrace_parent(task) == current); > > rcu_read_unlock(); > > if (match && ptrace_may_access(task, PTRACE_MODE_ATTACH)) > > All we need > > if (task_is_traced(task) && task->parent == current) { > if (ptrace_may_access() > return mm; > } > > Of course I do not blame this patch, my only point is that this helper > only adds more confusion imho. Yeah, it didn't seem like all the users actually required rcu dereferencing and both the tracehook and ptrace function names are confusing and not consistent in their use. We can convert the ones which don't require rcu dereferencing to use ->parent directly and if the left ones are few enough, maybe kill the helper altogether. Thanks. -- tejun -- 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/