From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 5AFE6C28CC5 for ; Thu, 6 Jun 2019 02:29:00 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3210A2070B for ; Thu, 6 Jun 2019 02:29:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726715AbfFFC27 (ORCPT ); Wed, 5 Jun 2019 22:28:59 -0400 Received: from smtprelay0082.hostedemail.com ([216.40.44.82]:55892 "EHLO smtprelay.hostedemail.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726454AbfFFC27 (ORCPT ); Wed, 5 Jun 2019 22:28:59 -0400 Received: from filter.hostedemail.com (clb03-v110.bra.tucows.net [216.40.38.60]) by smtprelay06.hostedemail.com (Postfix) with ESMTP id B0B5418224D78; Thu, 6 Jun 2019 02:28:57 +0000 (UTC) X-Session-Marker: 6A6F6540706572636865732E636F6D X-HE-Tag: leg41_13e178e1c213e X-Filterd-Recvd-Size: 3093 Received: from XPS-9350 (cpe-23-242-196-136.socal.res.rr.com [23.242.196.136]) (Authenticated sender: joe@perches.com) by omf13.hostedemail.com (Postfix) with ESMTPA; Thu, 6 Jun 2019 02:28:56 +0000 (UTC) Message-ID: Subject: Re: [PATCH] Input: alps: Drop unlikely before IS_ERR(_OR_NULL) From: Joe Perches To: Kefeng Wang , Pali =?ISO-8859-1?Q?Roh=E1r?= Cc: linux-kernel@vger.kernel.org, Dmitry Torokhov , linux-input@vger.kernel.org Date: Wed, 05 Jun 2019 19:28:53 -0700 In-Reply-To: <36eac452-5477-3670-7980-765d0879ead4@huawei.com> References: <20190605142428.84784-1-wangkefeng.wang@huawei.com> <20190605142428.84784-5-wangkefeng.wang@huawei.com> <20190605144240.pfrvlgxsdpacpwxf@pali> <36eac452-5477-3670-7980-765d0879ead4@huawei.com> Content-Type: text/plain; charset="ISO-8859-1" User-Agent: Evolution 3.30.5-0ubuntu0.18.10.1 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 2019-06-06 at 09:08 +0800, Kefeng Wang wrote: > On 2019/6/5 22:42, Pali Rohár wrote: > > On Wednesday 05 June 2019 22:24:28 Kefeng Wang wrote: > > > IS_ERR(_OR_NULL) already contain an 'unlikely' compiler flag, > > > so no need to do that again from its callers. Drop it. > > Hi! I already reviewed this patch and rejected it, see: > > https://patchwork.kernel.org/patch/10817475/ > OK, please ignore it. I think the stated reason of better readability isn't particularly sensible as the object code produced is actually slightly larger. x86-64 defconfig (gcc 8.3.0) $ size drivers/input/mouse/alps.o* text data bss dec hex filename 29416 56 0 29472 7320 drivers/input/mouse/alps.o.new 29432 56 0 29488 7330 drivers/input/mouse/alps.o.old Also if this unlikely is _really_ useful, perhaps the !IS_ERR immediately after could also use likely as the test seems only done for an OOM condition. > > > Cc: "Pali Rohár" > > > Cc: Dmitry Torokhov > > > Cc: linux-input@vger.kernel.org > > > Signed-off-by: Kefeng Wang > > > --- > > > drivers/input/mouse/alps.c | 2 +- > > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > > > diff --git a/drivers/input/mouse/alps.c b/drivers/input/mouse/alps.c > > > index 0a6f7ca883e7..791ef0f826c5 100644 > > > --- a/drivers/input/mouse/alps.c > > > +++ b/drivers/input/mouse/alps.c > > > @@ -1478,7 +1478,7 @@ static void alps_report_bare_ps2_packet(struct psmouse *psmouse, > > > /* On V2 devices the DualPoint Stick reports bare packets */ > > > dev = priv->dev2; > > > dev2 = psmouse->dev; > > > - } else if (unlikely(IS_ERR_OR_NULL(priv->dev3))) { > > > + } else if (IS_ERR_OR_NULL(priv->dev3)) { > > > /* Register dev3 mouse if we received PS/2 packet first time */ > > > if (!IS_ERR(priv->dev3)) > > > psmouse_queue_work(psmouse, &priv->dev3_register_work,