Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S263926AbUDVLJs (ORCPT ); Thu, 22 Apr 2004 07:09:48 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S263936AbUDVLJs (ORCPT ); Thu, 22 Apr 2004 07:09:48 -0400 Received: from mtagate7.de.ibm.com ([195.212.29.156]:49891 "EHLO mtagate7.de.ibm.com") by vger.kernel.org with ESMTP id S263926AbUDVLJr (ORCPT ); Thu, 22 Apr 2004 07:09:47 -0400 Subject: Re: [PATCH] s390 (9/9): no timer interrupts in idle. To: Arjan van de Ven Cc: akpm@osdl.org, linux-kernel@vger.kernel.org X-Mailer: Lotus Notes Release 5.0.11 July 24, 2002 Message-ID: From: Martin Schwidefsky Date: Thu, 22 Apr 2004 13:09:22 +0200 X-MIMETrack: Serialize by Router on D12ML062/12/M/IBM(Release 6.0.2CF2|July 23, 2003) at 22/04/2004 13:09:23 MIME-Version: 1.0 Content-type: text/plain; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 849 Lines: 25 > why? Most hardware have an alternative time source for such time stamps. > Timer events *won't* be delivered too late, simply *because* the timer said > "don't bother checking back for X amount of time", so when that time has > expired (eg the delay) then the timer comparison tells the kernel "ok this > one is due now". Huh? You lost me there. The HZ timer is the interrupt that will trigger the execution of a timer event. If you say "don't bother checking back for X amount of time" the cpu stays in idle doing nothing. You won't get control to execute the timer event. blue skies, Martin - 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/