From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756332AbYILDkJ (ORCPT ); Thu, 11 Sep 2008 23:40:09 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752341AbYILDj5 (ORCPT ); Thu, 11 Sep 2008 23:39:57 -0400 Received: from ozlabs.org ([203.10.76.45]:52884 "EHLO ozlabs.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752087AbYILDj4 (ORCPT ); Thu, 11 Sep 2008 23:39:56 -0400 From: Rusty Russell To: Arjan van de Ven Subject: Re: [PATCH 0/13] Turn hrtimers into a range capable timer Date: Fri, 12 Sep 2008 13:39:49 +1000 User-Agent: KMail/1.9.9 Cc: linux-kernel@vger.kernel.org, torvalds@linux-foundation.org, dwmw2@infradead.org, drepper@redhat.com, mingo@elte.hu, tglx@tglx.de References: <20080901160343.75a89ec9@infradead.org> In-Reply-To: <20080901160343.75a89ec9@infradead.org> MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200809121339.49902.rusty@rustcorp.com.au> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tuesday 02 September 2008 09:03:43 Arjan van de Ven wrote: > This series is a follow-on the the nanosecond select/poll series. > > The goal of this series is to introduce the capability into hrtimers to > deal with a "range" rather than a specific point in time. > (Several people discussed this recently, but we've been toying with the > concept for a while) Hi Arjen, sorry for not replying sooner. I had half a patch to create a new "timer layer to rule them all" called ktimers, which took an explicit "slop" value. Slop is the "how long before its worth waking the machine for this?" value, with friendly SLOP_USECS, SLOP_SECONDS, SLOP_DAYS etc defines. Implemented in terms of normal and hr timers, which get deprecated over time. Heuristics work for a while, but IMHO eventually this is going to have to be plumbed through to userspace. Cheers, Rusty.