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=-16.7 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,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 390D7C4338F for ; Tue, 24 Aug 2021 08:17:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 134CA61181 for ; Tue, 24 Aug 2021 08:17:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235262AbhHXISb (ORCPT ); Tue, 24 Aug 2021 04:18:31 -0400 Received: from mail.kernel.org ([198.145.29.99]:54770 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235167AbhHXISa (ORCPT ); Tue, 24 Aug 2021 04:18:30 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 11DD061220; Tue, 24 Aug 2021 08:17:45 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1629793067; bh=Uqh9V7RiyCOOsjNNGZXQDRCdogTxCQ6i/WZpirnIPUQ=; h=References:From:To:Cc:Subject:Date:In-reply-to:From; b=ZIO4STnhpm5yWomrTKSgkienTK9APTPRnjHapfckD0oDZ0e3b4sfuGfmrDh4T+PgM bAmozx7n1LHoUY4RXshwicbrlBCGcF1p4grgqh84hM+xdZmEnC+X25pP9tloKzuJ+a kAQiJGqS/3F9bttcujQBEpjGHa5HlAVwE22tIYd+wbS9J+R6nlB6v+4skcHn+C5SId q8H19mAsT8zh7R7BYnsT9bJwxpYvEkCJWYPKQQPrO2vI1kzmUErQRIJUFSo3Fm0BDO ACjpfr65eBQ2hgaOEq8IZlEFC5toYyky5w7NH1IgzKTa2/AfCKx4QW7ADh97DR4ERU t/CFfSSdW8oUQ== References: <1629777281-30188-1-git-send-email-quic_linyyuan@quicinc.com> <1629777281-30188-2-git-send-email-quic_linyyuan@quicinc.com> User-agent: mu4e 1.6.4; emacs 27.2 From: Felipe Balbi To: Linyu Yuan Cc: Greg Kroah-Hartman , linux-usb@vger.kernel.org Subject: Re: [PATCH V4 1/3] usb: gadget: configfs: add UDC trace entry Date: Tue, 24 Aug 2021 11:15:34 +0300 In-reply-to: <1629777281-30188-2-git-send-email-quic_linyyuan@quicinc.com> Message-ID: <8735qz8deg.fsf@kernel.org> MIME-Version: 1.0 Content-Type: text/plain Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org Hi, Linyu Yuan writes: > add trace in function gadget_dev_desc_UDC_store() > will show when user space enable/disable the gadget. > > Signed-off-by: Linyu Yuan > --- > drivers/usb/gadget/Makefile | 1 + > drivers/usb/gadget/configfs.c | 3 +++ > drivers/usb/gadget/configfs_trace.c | 7 +++++++ > drivers/usb/gadget/configfs_trace.h | 39 +++++++++++++++++++++++++++++++++++++ > 4 files changed, 50 insertions(+) > create mode 100644 drivers/usb/gadget/configfs_trace.c > create mode 100644 drivers/usb/gadget/configfs_trace.h > > diff --git a/drivers/usb/gadget/Makefile b/drivers/usb/gadget/Makefile > index 130dad7..8e9c2b8 100644 > --- a/drivers/usb/gadget/Makefile > +++ b/drivers/usb/gadget/Makefile > @@ -9,5 +9,6 @@ ccflags-y += -I$(srctree)/drivers/usb/gadget/udc > obj-$(CONFIG_USB_LIBCOMPOSITE) += libcomposite.o > libcomposite-y := usbstring.o config.o epautoconf.o > libcomposite-y += composite.o functions.o configfs.o u_f.o > +libcomposite-y += configfs_trace.o > > obj-$(CONFIG_USB_GADGET) += udc/ function/ legacy/ > diff --git a/drivers/usb/gadget/configfs.c b/drivers/usb/gadget/configfs.c > index 477e72a..f7f3af8 100644 > --- a/drivers/usb/gadget/configfs.c > +++ b/drivers/usb/gadget/configfs.c > @@ -9,6 +9,7 @@ > #include "configfs.h" > #include "u_f.h" > #include "u_os_desc.h" > +#include "configfs_trace.h" > > int check_user_usb_string(const char *name, > struct usb_gadget_strings *stringtab_dev) > @@ -270,6 +271,8 @@ static ssize_t gadget_dev_desc_UDC_store(struct config_item *item, > if (name[len - 1] == '\n') > name[len - 1] = '\0'; > > + trace_gadget_dev_desc_UDC_store(config_item_name(item), name); why tracing only the names? This gives us no insight into whatever bug may happen and we may want to use trace events to debug. Rather, try to think of trace events as tracking the lifetime of the UDC and gadget. Trace values that may change over time. I also think that all three patches could be combined into a single commit, but that's up to discussion. -- balbi