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 S1753248AbbFKSoG (ORCPT <rfc822;w@1wt.eu>);
	Thu, 11 Jun 2015 14:44:06 -0400
Received: from mail-wi0-f195.google.com ([209.85.212.195]:33446 "EHLO
	mail-wi0-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org
	with ESMTP id S1752275AbbFKSoD (ORCPT
	<rfc822;linux-kernel@vger.kernel.org>);
	Thu, 11 Jun 2015 14:44:03 -0400
Message-ID: <1434048238.3396.59.camel@gmail.com>
Subject: Re: RFC: futex_wait() can DoS the tick
From: Mike Galbraith <umgwanakikbuti@gmail.com>
To: Thomas Gleixner <tglx@linutronix.de>
Cc: LKML <linux-kernel@vger.kernel.org>, Peter Zijlstra <peterz@infradead.org>,
        Ingo Molnar <mingo@elte.hu>, Steven Rostedt <rostedt@goodmis.org>
Date: Thu, 11 Jun 2015 20:43:58 +0200
In-Reply-To: <alpine.DEB.2.11.1506111507560.3786@nanos>
References: <1433940278.6814.66.camel@gmail.com>
	 <alpine.DEB.2.11.1506101639230.3786@nanos>
	 <1433957421.6306.28.camel@gmail.com>
	 <alpine.DEB.2.11.1506102059010.3786@nanos>
	 <1433989634.3411.15.camel@gmail.com>
	 <alpine.DEB.2.11.1506111030350.3786@nanos>
	 <1434022875.4051.5.camel@gmail.com>
	 <alpine.DEB.2.11.1506111507560.3786@nanos>
Content-Type: text/plain; charset="UTF-8"
X-Mailer: Evolution 3.12.11 
Mime-Version: 1.0
Content-Transfer-Encoding: 7bit
Sender: linux-kernel-owner@vger.kernel.org
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org

On Thu, 2015-06-11 at 15:13 +0200, Thomas Gleixner wrote:

> The kernel does not care whether the actual interrupt happens or the
> timer is expired by other means.

Final question: Notabug explanation fits.. but why would the behavior
delta be so radical and repeatable w/wo deadline timer on some boxen?

	-Mike