Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751988Ab1FIAok (ORCPT ); Wed, 8 Jun 2011 20:44:40 -0400 Received: from science.horizon.com ([71.41.210.146]:40700 "HELO science.horizon.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with SMTP id S1751215Ab1FIAoh (ORCPT ); Wed, 8 Jun 2011 20:44:37 -0400 Date: 8 Jun 2011 20:44:35 -0400 Message-ID: <20110609004435.14550.qmail@science.horizon.com> From: "George Spelvin" To: david@rgmadvisors.com, dvhart@linux.intel.com, kyle@moffetthome.net, luto@mit.edu Subject: Re: Change in functionality of futex() system call. Cc: linux@horizon.com, linux-kernel@vger.kernel.org Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 701 Lines: 15 I'm not sure if it's best, but the risk of RO waiters interfering could be solved by giving them a lower prioirty for wakeup and always waking RW-mapped waiters first. In most cases, there would only be one type of waiter, so this would have no effect, but if there were, a RO-mapped reader couldn't "steal" wakeup from someone who had it RW-mapped. It might conflict with a fairness goal, but it does solve the problem without any extension to the API. -- 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/