Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754212Ab0KIVFf (ORCPT ); Tue, 9 Nov 2010 16:05:35 -0500 Received: from smtp-out.google.com ([74.125.121.35]:51654 "EHLO smtp-out.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751379Ab0KIVFe (ORCPT ); Tue, 9 Nov 2010 16:05:34 -0500 DomainKey-Signature: a=rsa-sha1; c=nofws; d=google.com; s=beta; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type; b=ScKHEpyDv+Rp6wZYSax8T6EtNWS8NvbiFwpZHBhDBuvywKZqbg9F1PZondKu/tRwDv hVFQEKF+PgMDROoPKRHQ== MIME-Version: 1.0 In-Reply-To: <4CD78946.5060405@cn.fujitsu.com> References: <4CC146A4.9090505@cn.fujitsu.com> <4CC146BA.7080009@cn.fujitsu.com> <4CD78946.5060405@cn.fujitsu.com> Date: Tue, 9 Nov 2010 13:05:31 -0800 Message-ID: Subject: Re: [PATCH 1/7] cgroups: Shrink struct cgroup_subsys From: Paul Menage To: Li Zefan Cc: "akpm >> Andrew Morton" , Stephane Eranian , LKML , containers@lists.linux-foundation.org Content-Type: text/plain; charset=ISO-8859-1 X-System-Of-Record: true Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 711 Lines: 26 On Sun, Nov 7, 2010 at 9:23 PM, Li Zefan wrote: > > bool active; > bool disabled; > ... > > ? > > With alignment 5-8 bool values == 8 bytes in 64-bit machine, compared to > 4 bytes with the approach this patch takes. I meant specifying it as: bool active:1; bool disabled:1; i.e. keeping the bit-sized flags but also keeping the bool semantics. Having said that, I'm not really sure why saving 12 bytes per subsystem is worth a patch. Paul -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/