From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755166Ab0FXLfA (ORCPT ); Thu, 24 Jun 2010 07:35:00 -0400 Received: from bombadil.infradead.org ([18.85.46.34]:50810 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752205Ab0FXLe7 convert rfc822-to-8bit (ORCPT ); Thu, 24 Jun 2010 07:34:59 -0400 Subject: Re: [RFC][PATCH] irq_work From: Peter Zijlstra To: Ingo Molnar Cc: Andi Kleen , Huang Ying , "H.PeterA" <"nvin hpa"@zytor.com>, linux-kernel@vger.kernel.org In-Reply-To: <20100624112340.GA13502@elte.hu> References: <1277363069.3947.30.camel@yhuang-dev.sh.intel.com> <1277363993.1875.847.camel@laptop> <1277364453.3947.64.camel@yhuang-dev.sh.intel.com> <1277364727.1875.857.camel@laptop> <20100624102725.GA578@basil.fritz.box> <1277375409.1875.943.camel@laptop> <20100624105254.GB578@basil.fritz.box> <1277377121.1875.948.camel@laptop> <20100624110830.GC578@basil.fritz.box> <1277377852.1875.950.camel@laptop> <20100624112340.GA13502@elte.hu> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 8BIT Date: Thu, 24 Jun 2010 13:34:54 +0200 Message-ID: <1277379294.1875.959.camel@laptop> Mime-Version: 1.0 X-Mailer: Evolution 2.28.3 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 2010-06-24 at 13:23 +0200, Ingo Molnar wrote: > What might make sense is to offer two types of callbacks: one that is > immediate whenever an event triggers - and another that is sleepable and is > executed from process context. Trouble is waking that thread, you cannot wake tasks from NMI context, so whatever you do, you'll end up with a trampoline. You could of course offer that trampoline nicely packaged, but I'm not sure that's really worth the effort.