From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754056AbZAaJZz (ORCPT ); Sat, 31 Jan 2009 04:25:55 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1751290AbZAaJZj (ORCPT ); Sat, 31 Jan 2009 04:25:39 -0500 Received: from earthlight.etchedpixels.co.uk ([81.2.110.250]:50593 "EHLO lxorguk.ukuu.org.uk" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1750720AbZAaJZi (ORCPT ); Sat, 31 Jan 2009 04:25:38 -0500 Date: Sat, 31 Jan 2009 09:25:09 +0000 From: Alan Cox To: Ingo Molnar Cc: Davide Libenzi , Linux Kernel Mailing List , Andrew Morton , Linus Torvalds , David Miller Subject: Re: [patch 3/7] epoll keyed wakeups - introduce key-aware wakeup macros Message-ID: <20090131092509.7c658b22@lxorguk.ukuu.org.uk> In-Reply-To: <20090131033035.GA26640@elte.hu> References: <20090131033035.GA26640@elte.hu> X-Mailer: Claws Mail 3.5.0 (GTK+ 2.12.12; x86_64-redhat-linux-gnu) Organization: Red Hat UK Cyf., Amberley Place, 107-111 Peascod Street, Windsor, Berkshire, SL4 1TE, Y Deyrnas Gyfunol. Cofrestrwyd yng Nghymru a Lloegr o'r rhif cofrestru 3798903 Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > One minor worry i have: these wakeup calls are _very_ common in the > kernel, and this patch adds an extra parameter to it that is unused (NULL) > in 99% of the cases. And in most of the cases it is used is constant for the waitqueue anyway or appears to be (eg the tty patch). I don't think we should be stacking extra parameters on all those zillions of calls made all over the kernel and for no purpose - so the existing wakeup functions should stay as is for performance as well as for size (which due to cache pressure is performance). Alan