Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760164Ab0HELko (ORCPT ); Thu, 5 Aug 2010 07:40:44 -0400 Received: from casper.infradead.org ([85.118.1.10]:49112 "EHLO casper.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759080Ab0HELkm convert rfc822-to-8bit (ORCPT ); Thu, 5 Aug 2010 07:40:42 -0400 Subject: Re: [PATCH] stop_machine: struct cpu_stopper, remove alignment padding on 64 bits From: Peter Zijlstra To: Richard Kennedy Cc: Tejun Heo , lkml , Ingo Molnar In-Reply-To: <1281006717.2000.12.camel@castor.rsk> References: <1281006717.2000.12.camel@castor.rsk> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 8BIT Date: Thu, 05 Aug 2010 13:40:35 +0200 Message-ID: <1281008435.1923.1820.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 Content-Length: 1217 Lines: 34 On Thu, 2010-08-05 at 12:11 +0100, Richard Kennedy wrote: > Reorder elements in structure cpu_stopper to remove alignment padding on > 64 bit builds, this shrinks its size from 40 to 32 bytes saving 8 bytes > per cpu. > > Signed-off-by: Richard Kennedy Looks good to me. Tejun will you take it or should I send it Ingo wards? > --- > diff --git a/kernel/stop_machine.c b/kernel/stop_machine.c > index 70f8d90..4372ccb 100644 > --- a/kernel/stop_machine.c > +++ b/kernel/stop_machine.c > @@ -35,9 +35,9 @@ struct cpu_stop_done { > /* the actual stopper, one per every possible cpu, enabled on online cpus */ > struct cpu_stopper { > spinlock_t lock; > + bool enabled; /* is this stopper enabled? */ > struct list_head works; /* list of pending works */ > struct task_struct *thread; /* stopper thread */ > - bool enabled; /* is this stopper enabled? */ > }; > > static DEFINE_PER_CPU(struct cpu_stopper, cpu_stopper); > > -- 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/