From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tejun Heo Subject: Re: [PATCH 09/12] irq: implement IRQ expecting Date: Sat, 19 Jun 2010 10:42:51 +0200 Message-ID: <4C1C830B.5020806@kernel.org> References: <1276443098-20653-1-git-send-email-tj@kernel.org> <1276443098-20653-10-git-send-email-tj@kernel.org> <20100616204854.4b036f87@infradead.org> <87zkyro1xl.fsf@basil.nowhere.org> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Return-path: Received: from hera.kernel.org ([140.211.167.34]:46592 "EHLO hera.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751143Ab0FSIoF (ORCPT ); Sat, 19 Jun 2010 04:44:05 -0400 In-Reply-To: <87zkyro1xl.fsf@basil.nowhere.org> Sender: linux-ide-owner@vger.kernel.org List-Id: linux-ide@vger.kernel.org To: Andi Kleen Cc: Arjan van de Ven , mingo@elte.hu, tglx@linutronix.de, bphilips@suse.de, yinghai@kernel.org, akpm@linux-foundation.org, torvalds@linux-foundation.org, linux-kernel@vger.kernel.org, jeff@garzik.org, linux-ide@vger.kernel.org, stern@rowland.harvard.edu, gregkh@suse.de, khali@linux-fr.org Hello, On 06/19/2010 10:35 AM, Andi Kleen wrote: >> I would like to suggest an (optional) argument to this with a duration >> within which to expect an interrupt.... >> >> that way in the backend we can plumb this also into the idle handler >> for C state selection... > > I'm not sure it's really that useful to power optimize > the lost interrupts polling case. It's just a last resort > fallback anyways and will be always less power efficient > because there will be unnecessary polls. IIUC, it's not to help or optimize polling itself. It just gives us a way to estimate when the next interrupt would be so that power can be optimized for non polling cases. Thanks. -- tejun