From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1166186AbdDXHcv (ORCPT ); Mon, 24 Apr 2017 03:32:51 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:58540 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1166133AbdDXHcm (ORCPT ); Mon, 24 Apr 2017 03:32:42 -0400 Date: Mon, 24 Apr 2017 08:32:32 +0100 From: Greg Kroah-Hartman To: Wei Li Cc: linux-kernel@vger.kernel.org, vatsa@codeaurora.org Subject: Re: [PATCH] driver-core: remove lock for platform devices during probe Message-ID: <20170424073232.GA19970@kroah.com> References: <1493012536-9240-1-git-send-email-weili@codeaurora.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1493012536-9240-1-git-send-email-weili@codeaurora.org> User-Agent: Mutt/1.8.2 (2017-04-18) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Apr 24, 2017 at 01:42:16PM +0800, Wei Li wrote: > During driver probe procedure, lock on the parent of > platform devices could be removed to make probe in > parallel. > > Signed-off-by: Wei Li Why? Why does this matter? > --- > drivers/base/dd.c | 6 ++++-- > 1 file changed, 4 insertions(+), 2 deletions(-) > > diff --git a/drivers/base/dd.c b/drivers/base/dd.c > index a1fbf55..e238fbc 100644 > --- a/drivers/base/dd.c > +++ b/drivers/base/dd.c > @@ -25,6 +25,7 @@ > #include > #include > #include > +#include > > #include "base.h" > #include "power/power.h" > @@ -749,13 +750,14 @@ static int __driver_attach(struct device *dev, void *data) > return ret; > } /* ret > 0 means positive match */ > > - if (dev->parent) /* Needed for USB */ > + if (dev->parent && > + (dev->bus != &platform_bus_type)) /* Needed for USB */ The platform_bus_type check is not needed by USB, right? thanks, greg k-h