From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <linux-kernel-owner@vger.kernel.org>
Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand
	id S1752150Ab1IZQQ4 (ORCPT <rfc822;w@1wt.eu>);
	Mon, 26 Sep 2011 12:16:56 -0400
Received: from e4.ny.us.ibm.com ([32.97.182.144]:34031 "EHLO e4.ny.us.ibm.com"
	rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP
	id S1751481Ab1IZQQz (ORCPT <rfc822;linux-kernel@vger.kernel.org>);
	Mon, 26 Sep 2011 12:16:55 -0400
Date: Mon, 26 Sep 2011 21:31:44 +0530
From: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
To: Peter Zijlstra <peterz@infradead.org>
Cc: Ingo Molnar <mingo@elte.hu>, Steven Rostedt <rostedt@goodmis.org>,
        Linux-mm <linux-mm@kvack.org>,
        Arnaldo Carvalho de Melo <acme@infradead.org>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Jonathan Corbet <corbet@lwn.net>, Hugh Dickins <hughd@google.com>,
        Christoph Hellwig <hch@infradead.org>,
        Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        Ananth N Mavinakayanahalli <ananth@in.ibm.com>,
        Oleg Nesterov <oleg@redhat.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Jim Keniston <jkenisto@linux.vnet.ibm.com>,
        Roland McGrath <roland@hack.frob.com>,
        Andi Kleen <andi@firstfloor.org>, LKML <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH v5 3.1.0-rc4-tip 12/26]   Uprobes: Handle breakpoint
 and Singlestep
Message-ID: <20110926160144.GC13535@linux.vnet.ibm.com>
Reply-To: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
References: <20110920115938.25326.93059.sendpatchset@srdronam.in.ibm.com>
 <20110920120221.25326.74714.sendpatchset@srdronam.in.ibm.com>
 <1317045553.1763.23.camel@twins>
MIME-Version: 1.0
Content-Type: text/plain; charset=iso-8859-1
Content-Disposition: inline
In-Reply-To: <1317045553.1763.23.camel@twins>
User-Agent: Mutt/1.5.20 (2009-06-14)
Sender: linux-kernel-owner@vger.kernel.org
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org

* Peter Zijlstra <peterz@infradead.org> [2011-09-26 15:59:13]:

> On Tue, 2011-09-20 at 17:32 +0530, Srikar Dronamraju wrote:
> > 						Hence provide some extra
> > + * time (by way of synchronize_sched() for breakpoint hit threads to acquire
> > + * the uprobes_treelock before the uprobe is removed from the rbtree. 
> 
> 'Some extra time' doesn't make me all warm an fuzzy inside, but instead
> screams we fudge around a race condition.

The extra time provided is sufficient to avoid the race. So will modify
it to mean "sufficient" instead of "some".   

Would that suffice?

-- 
Thanks and Regards
Srikar