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=-8.3 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 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 0B08CC5DF60 for ; Thu, 7 Nov 2019 09:16:42 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id CFDED218AE for ; Thu, 7 Nov 2019 09:16:41 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="fZ5nOarx"; dkim=fail reason="signature verification failed" (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="CHrZk6ee" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org CFDED218AE Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linuxfoundation.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-mediatek-bounces+linux-mediatek=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=hXb1Cd2p4e33tT24uOQYNaD1nRaohJSn2skf/qpmUzM=; b=fZ5nOarxuVQxP2 2R435n8dbtVT11S+seYsl2nCAN3lkauU/koIXITYJq81gpok2zig5t+9nkXIPX3Z/YVqNfXSXhf2v I79XNK0KY6aWmeu1eSwMfb9xxX2Rc9cOG3I4hYsVr/kRHQslptfa0uJrRZ1mRlV4ONLLH6Z4GOnrf w3Kh2FPb2BLWKZsOzvTxVmKoctKYN8W8emweoeJHolULMXvmFsTHp1/zrH3JtMc/0GKFrt6hX8bj4 KoQgBY8gPkR3rfi33JQgIZ6kpDozpQS8VkyROQqZuxVcRD1vWKwufCj80XVzi7i+verkawxhRDvBn 8A3OmCF1Orf8FAI1k3rw==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1iSdu2-00026O-Rp; Thu, 07 Nov 2019 09:16:30 +0000 Received: from mail.kernel.org ([198.145.29.99]) by bombadil.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1iSdtz-00025m-IS; Thu, 07 Nov 2019 09:16:28 +0000 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 689F32166E; Thu, 7 Nov 2019 09:16:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1573118187; bh=TM7UP3cWbiGJEghjGH72vosIqE/f6U3eHuTpEBJUzB0=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=CHrZk6eeNGL4z9nRRQYjNVJWuVYJi9msnRuyWAcY62tsE4SsEefl2qKhZ6gEVdo0h Ec2Pg37dZUXAFmkabt9kYbD9qxDrqXdcGGVshQPFlhI+VdGzIc3JFQB2VIbSaKdcc7 oaKYp/keyy+cIJBTWXQp5zI/dEBY6G/kGzcdh6cM= Date: Thu, 7 Nov 2019 10:16:24 +0100 From: Greg Kroah-Hartman To: Chunfeng Yun Subject: Re: [PATCH 01/28] usb: common: change usb_debug_root as static variable Message-ID: <20191107091624.GB1328892@kroah.com> References: <8cb137d5376b4e317dc22dcb9e81a1125b781f8f.1573008519.git.chunfeng.yun@mediatek.com> <79fd2ebd-b8c6-ee00-c71e-782475a20de6@roeck-us.net> <1573031491.18464.70.camel@mhfsdcap03> <2e793636-04a6-8589-b4a5-259f79a5ea02@roeck-us.net> <1573117594.18464.87.camel@mhfsdcap03> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <1573117594.18464.87.camel@mhfsdcap03> User-Agent: Mutt/1.12.2 (2019-09-21) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20191107_011627_651225_92D97AB4 X-CRM114-Status: GOOD ( 26.07 ) X-BeenThere: linux-mediatek@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Peter Chen , Alexandre Belloni , Heikki Krogerus , Wolfram Sang , Yangtao Li , Linus Walleij , linux-kernel@vger.kernel.org, Matthias Brugger , Mans Rullgard , Srinivas Kandagatla , Laurent Pinchart , Fabio Estevam , Florian Fainelli , Robert Jarzmik , Kevin Cernekee , "Gustavo A. R. Silva" , Ludovic Desroches , Alan Stern , NXP Linux Team , bcm-kernel-feedback-list@broadcom.com, David Kershner , Hans Ulli Kroll , Cristian Birsan , linux-media@vger.kernel.org, Fabrizio Castro , Mathias Payer , Mathias Nyman , Suzuki K Poulose , Sascha Hauer , Haojian Zhuang , Stephen Boyd , linux-mediatek@lists.infradead.org, Minas Harutyunyan , Simon Horman , Mauro Carvalho Chehab , Bin Liu , linux-arm-kernel@lists.infradead.org, Biju Das , Felipe Balbi , Laurentiu Tudor , Yoshihiro Shimoda , linux-usb@vger.kernel.org, Nicolas Ferre , Dmitry Torokhov , Guenter Roeck , Pengutronix Kernel Team , Colin Ian King , Shawn Guo , Daniel Mack Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "Linux-mediatek" Errors-To: linux-mediatek-bounces+linux-mediatek=archiver.kernel.org@lists.infradead.org On Thu, Nov 07, 2019 at 05:06:34PM +0800, Chunfeng Yun wrote: > Hi Greg, > > On Wed, 2019-11-06 at 06:00 -0800, Guenter Roeck wrote: > > On 11/6/19 1:11 AM, Chunfeng Yun wrote: > > > On Tue, 2019-11-05 at 20:03 -0800, Guenter Roeck wrote: > > >> On 11/5/19 7:15 PM, Chunfeng Yun wrote: > > >>> Try to avoid using extern global variable, and provide two > > >>> functions for the usage cases > > >>> > > >>> Signed-off-by: Chunfeng Yun > > >>> --- > > >>> drivers/usb/common/common.c | 16 ++++++++++++++-- > > >>> include/linux/usb.h | 5 ++++- > > >>> 2 files changed, 18 insertions(+), 3 deletions(-) > > >>> > > >>> diff --git a/drivers/usb/common/common.c b/drivers/usb/common/common.c > > >>> index 1433260d99b4..639ee6d243a2 100644 > > >>> --- a/drivers/usb/common/common.c > > >>> +++ b/drivers/usb/common/common.c > > >>> @@ -293,8 +293,20 @@ struct device *usb_of_get_companion_dev(struct device *dev) > > >>> EXPORT_SYMBOL_GPL(usb_of_get_companion_dev); > > >>> #endif > > >>> > > >>> -struct dentry *usb_debug_root; > > >>> -EXPORT_SYMBOL_GPL(usb_debug_root); > > >>> +static struct dentry *usb_debug_root; > > >>> + > > >> > > >> I don't think it is a good idea to declare this variable static > > >> before all its uses are removed. This patch will leave the system > > >> in a non-compileable state until all patches of the series have > > >> been applied. > > > Yes, you are right, I'll fix it, may be split into two patch > > > > > >> > > >> I am curious. What is the rationale for this change ? > > >> Did exported variables run out of favor ? > > > Personally, I think it's good practice to avoid global varibale, > > > it may not a good reason. > > > > Personally I don't think it is a good reason at all. When you are done, > > someone else may come in and declare the opposite, re-introduce the global > > variable, and drop the new functions as unnecessary. > > > > This is ok for new code, but I think we should leave existing code alone > > unless it is broken and needs to get fixed. This is not the case here. > What do you think about this, if you also agree with Guenter's opinion, I do. > I'll abandon this patch. Please do. > BTW, how about moving udc's debug directory into usb root? Sure, feel free to send a patch for that. thanks, greg k-h _______________________________________________ Linux-mediatek mailing list Linux-mediatek@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-mediatek