Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758406AbXEIP7c (ORCPT ); Wed, 9 May 2007 11:59:32 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1756093AbXEIP7Z (ORCPT ); Wed, 9 May 2007 11:59:25 -0400 Received: from mga01.intel.com ([192.55.52.88]:19384 "EHLO mga01.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755105AbXEIP7Y convert rfc822-to-8bit (ORCPT ); Wed, 9 May 2007 11:59:24 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.14,510,1170662400"; d="scan'208";a="243831212" X-MimeOLE: Produced By Microsoft Exchange V6.5 Content-Class: urn:content-classes:message MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 8BIT Subject: RE: [PATCH -mm] timer: parenthesis fix in tbase_get_deferrable() etc. Date: Wed, 9 May 2007 08:59:27 -0700 Message-ID: <653FFBB4508B9042B5D43DC9E18836F55DF9FD@scsmsx415.amr.corp.intel.com> In-Reply-To: <20070509053144.GA995@ff.dom.local> X-MS-Has-Attach: X-MS-TNEF-Correlator: Thread-Topic: [PATCH -mm] timer: parenthesis fix in tbase_get_deferrable() etc. thread-index: AceR+nJI6GkcIdzyRl+4v2vLIMzJhQAV1K+g From: "Pallipadi, Venkatesh" To: "Jarek Poplawski" , "Andrew Morton" CC: , "Oleg Nesterov" X-OriginalArrivalTime: 09 May 2007 15:59:22.0711 (UTC) FILETIME=[029CA670:01C79253] Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1927 Lines: 57 >-----Original Message----- >From: Jarek Poplawski [mailto:jarkao2@o2.pl] >Sent: Tuesday, May 08, 2007 10:32 PM >To: Andrew Morton >Cc: Pallipadi, Venkatesh; linux-kernel@vger.kernel.org; Oleg Nesterov >Subject: Re: [PATCH -mm] timer: parenthesis fix in >tbase_get_deferrable() etc. > >On Tue, May 08, 2007 at 04:33:58PM -0700, Andrew Morton wrote: >> On Tue, 8 May 2007 12:33:48 +0200 >> Jarek Poplawski wrote: >> >> > >> > Signed-off-by: Jarek Poplawski >> > >> > --- >> > >> > diff -Nurp 2.6.21-mm1-/kernel/timer.c 2.6.21-mm1/kernel/timer.c >> > --- 2.6.21-mm1-/kernel/timer.c 2007-05-08 >11:54:48.000000000 +0200 >> > +++ 2.6.21-mm1/kernel/timer.c 2007-05-08 >12:05:11.000000000 +0200 >> > @@ -92,24 +92,24 @@ static DEFINE_PER_CPU(tvec_base_t *, tve >> > /* Functions below help us manage 'deferrable' flag */ >> > static inline unsigned int tbase_get_deferrable(tvec_base_t *base) >> > { >> > - return ((unsigned int)(unsigned long)base & >TBASE_DEFERRABLE_FLAG); >> > + return (unsigned int)((unsigned long)base & >TBASE_DEFERRABLE_FLAG); >> > } >... >> The change makes sense, but does it actually "fix" anything? >> > >Yes - this first place fixes logical error, so it's a sin >- even if not punishable in practice. (It's also unnecessary >test for long to int conversion.) > I am sorry, I don't understand. What is the logical error in the first one? Actually, your change makes it different from what was originally indended. Original intention was to type convert base to a 32 bit value and bitwise& with FLAG. Even though compiler may optimize both the above to same code, I don't see what is the error. Thanks, Venki - 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/