From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S964782AbWGEJyD (ORCPT ); Wed, 5 Jul 2006 05:54:03 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S964785AbWGEJyD (ORCPT ); Wed, 5 Jul 2006 05:54:03 -0400 Received: from smtp.osdl.org ([65.172.181.4]:5536 "EHLO smtp.osdl.org") by vger.kernel.org with ESMTP id S964782AbWGEJyB (ORCPT ); Wed, 5 Jul 2006 05:54:01 -0400 Date: Wed, 5 Jul 2006 02:53:49 -0700 From: Andrew Morton To: Ingo Molnar Cc: torvalds@osdl.org, linux-kernel@vger.kernel.org, arjan@infradead.org Subject: Re: [patch] uninline init_waitqueue_*() functions Message-Id: <20060705025349.eb88b237.akpm@osdl.org> In-Reply-To: <20060705093259.GA11237@elte.hu> References: <20060705084914.GA8798@elte.hu> <20060705023120.2b70add6.akpm@osdl.org> <20060705093259.GA11237@elte.hu> X-Mailer: Sylpheed version 2.2.4 (GTK+ 2.8.17; i686-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 5 Jul 2006 11:32:59 +0200 Ingo Molnar wrote: > > * Andrew Morton wrote: > > > shrinks fs/select.o by eight bytes. (More than I expected). So it > > does appear to be a space win, but a pretty slim one. > > there are 855 calls to these functions in the allyesconfig vmlinux i > did, and i measured a combined size reduction of 34791 bytes. That > averages to a 40 bytes win per call site. (on i386.) > Yes, but that lumps all three together. init_waitqueue_head() is obviously the porky one. And it's porkier with CONFIG_DEBUG_SPINLOCK and CONFIG_LOCKDEP, which isn't the case to optimise for. With the debug options turned off, even init_waitqueue_head() becomes just three assignments, similar to init_waitqueue_entry() and init_waitqueue_func_entry(). All pretty marginal.