From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932687AbdEVBVm (ORCPT ); Sun, 21 May 2017 21:21:42 -0400 Received: from mailgw01.mediatek.com ([218.249.47.110]:35589 "EHLO mailgw01.mediatek.com" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1756970AbdEVBVk (ORCPT ); Sun, 21 May 2017 21:21:40 -0400 Message-ID: <1495416093.25536.6.camel@mhfsdcap03> Subject: Re: [PATCH] usb: mtu3: cleanup with list_first_entry_or_null() From: Chunfeng Yun To: Greg Kroah-Hartman CC: Masahiro Yamada , , Date: Mon, 22 May 2017 09:21:33 +0800 In-Reply-To: <20170520191940.GA29597@kroah.com> References: <1495299931-10418-1-git-send-email-yamada.masahiro@socionext.com> <20170520191940.GA29597@kroah.com> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.2.3-0ubuntu6 Content-Transfer-Encoding: 7bit MIME-Version: 1.0 X-MTK: N Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, On Sat, 2017-05-20 at 21:19 +0200, Greg Kroah-Hartman wrote: > On Sun, May 21, 2017 at 02:05:31AM +0900, Masahiro Yamada wrote: > > The combo of list_empty() and list_first_entry() can be replaced with > > list_first_entry_or_null(). > > > > Signed-off-by: Masahiro Yamada > > --- > > > > drivers/usb/mtu3/mtu3.h | 8 ++------ > > 1 file changed, 2 insertions(+), 6 deletions(-) > > > > diff --git a/drivers/usb/mtu3/mtu3.h b/drivers/usb/mtu3/mtu3.h > > index aa6fd6a..7b6dc23 100644 > > --- a/drivers/usb/mtu3/mtu3.h > > +++ b/drivers/usb/mtu3/mtu3.h > > @@ -356,12 +356,8 @@ static inline struct mtu3_ep *to_mtu3_ep(struct usb_ep *ep) > > > > static inline struct mtu3_request *next_request(struct mtu3_ep *mep) > > { > > - struct list_head *queue = &mep->req_list; > > - > > - if (list_empty(queue)) > > - return NULL; > > - > > - return list_first_entry(queue, struct mtu3_request, list); > > + return list_first_entry_or_null(&mep->req_list, struct mtu3_request, > > + list); > > Even better, why is this an inlined function at all? Why not just have > it "open coded" everywhere it is used? > This can avoid repeated function definition, currently it is used in three files. > thanks, > > greg k-h