From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753603AbaAKUCz (ORCPT ); Sat, 11 Jan 2014 15:02:55 -0500 Received: from smtprelay0023.hostedemail.com ([216.40.44.23]:51483 "EHLO smtprelay.hostedemail.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751616AbaAKUCy (ORCPT ); Sat, 11 Jan 2014 15:02:54 -0500 X-Session-Marker: 6A6F6540706572636865732E636F6D X-Spam-Summary: 2,0,0,,d41d8cd98f00b204,joe@perches.com,:::::::::::::,RULES_HIT:41:355:379:541:599:800:960:973:988:989:1260:1261:1277:1311:1313:1314:1345:1359:1373:1437:1515:1516:1518:1534:1540:1593:1594:1711:1730:1747:1777:1792:2198:2199:2393:2559:2562:2828:3138:3139:3140:3141:3142:3352:3622:3865:3866:3867:3870:4321:5007:6119:6120:7514:7652:7901:7903:10004:10400:10848:11026:11232:11657:11658:11914:12043:12296:12438:12517:12519:12740:13069:13095:13161:13229:13311:13357,0,RBL:none,CacheIP:none,Bayesian:0.5,0.5,0.5,Netcheck:none,DomainCache:0,MSF:not bulk,SPF:fn,MSBL:0,DNSBL:none,Custom_rules:0:0:0 X-HE-Tag: trail09_532c043c07e61 X-Filterd-Recvd-Size: 1825 Message-ID: <1389470568.2537.81.camel@joe-AO722> Subject: Re: [PATCH v2] Staging: lustre: Use of fls to find last set bit From: Joe Perches To: Monam Agarwal Cc: gregkh@linuxfoundation.org, andreas.dilger@intel.com, peter.p.waskiewicz.jr@intel.com, tao.peng@emc.com, devel@driverdev.osuosl.org, linux-kernel@vger.kernel.org Date: Sat, 11 Jan 2014 12:02:48 -0800 In-Reply-To: <1389468763-25662-1-git-send-email-monamagarwal123@gmail.com> References: <1389440466-6895-1-git-send-email-monamagarwal123@gmail.com> <1389468763-25662-1-git-send-email-monamagarwal123@gmail.com> Content-Type: text/plain; charset="ISO-8859-1" X-Mailer: Evolution 3.8.4-0ubuntu1 Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sun, 2014-01-12 at 01:02 +0530, Monam Agarwal wrote: > This introduces fls in lustre/ldlm/ldlm_extent.c > to find the last set bit. [] > Signed-off-by: Monam Agarwal > --- > Changes since v1: > *Incorrect commit message > *Use of fls function [] > diff --git a/drivers/staging/lustre/lustre/ldlm/ldlm_extent.c b/drivers/staging/lustre/lustre/ldlm/ldlm_extent.c [] > @@ -150,10 +150,12 @@ struct ldlm_interval *ldlm_interval_detach(struct ldlm_lock *l) > static inline int lock_mode_to_index(ldlm_mode_t mode) > { > int index; > + int len; > > LASSERT(mode != 0); > LASSERT(IS_PO2(mode)); > - for (index = -1; mode; index++, mode >>= 1) ; > + len = fls(mode); > + index = len-1; There's no need for len at all. index = fls(mode) - 1; would be fine.