Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755101Ab0LCNbE (ORCPT ); Fri, 3 Dec 2010 08:31:04 -0500 Received: from e32.co.us.ibm.com ([32.97.110.150]:34718 "EHLO e32.co.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751692Ab0LCNbC (ORCPT ); Fri, 3 Dec 2010 08:31:02 -0500 Date: Fri, 3 Dec 2010 19:00:57 +0530 From: Srivatsa Vaddagiri To: Peter Zijlstra Cc: Rik van Riel , kvm@vger.kernel.org, linux-kernel@vger.kernel.org, Avi Kiviti , Ingo Molnar , Anthony Liguori Subject: Re: [RFC PATCH 2/3] sched: add yield_to function Message-ID: <20101203133056.GF27994@linux.vnet.ibm.com> Reply-To: vatsa@linux.vnet.ibm.com References: <20101202144129.4357fe00@annuminas.surriel.com> <20101202144423.3ad1908d@annuminas.surriel.com> <1291382619.32004.2124.camel@laptop> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1291382619.32004.2124.camel@laptop> User-Agent: Mutt/1.5.20 (2009-06-14) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 696 Lines: 20 On Fri, Dec 03, 2010 at 02:23:39PM +0100, Peter Zijlstra wrote: > Right, so another approach might be to simply swap the vruntime between > curr and p. Can't that cause others to stave? For ex: consider a cpu p0 having these tasks: p0 -> A0 B0 A1 A0/A1 have entered some sort of AB<->BA spin-deadlock, as a result A0 wants to direct yield to A1 which wants to direct yield to A0. If we keep swapping their runtimes, can't it starve B0? - vatsa -- 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/