From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754038AbdEQHog (ORCPT ); Wed, 17 May 2017 03:44:36 -0400 Received: from fllnx210.ext.ti.com ([198.47.19.17]:17464 "EHLO fllnx210.ext.ti.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753642AbdEQHoc (ORCPT ); Wed, 17 May 2017 03:44:32 -0400 Subject: Re: [PATCH] usb: dwc3: gadget: Fix ISO transfer performance To: References: <1492779488-15127-1-git-send-email-rogerq@ti.com> CC: , , From: Roger Quadros Message-ID: <0b5968b0-0451-b892-4798-4df33e2aac33@ti.com> Date: Wed, 17 May 2017 10:44:17 +0300 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.8.0 MIME-Version: 1.0 In-Reply-To: <1492779488-15127-1-git-send-email-rogerq@ti.com> Content-Type: text/plain; charset="windows-1252" Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Felipe, On 21/04/17 15:58, Roger Quadros wrote: > Commit 08a36b543803 ("usb: dwc3: gadget: simplify __dwc3_gadget_ep_queue()") > caused a small change in the way ISO transfer is handled in the case > when XferInProgress event happens on Isoc EP with an active transfer. > This caused a performance degradation of 50%. e.g. using g_webcam on DUT > and luvcview on host the video frame rate dropped from 16fps to 8fps > @high-speed. > > Make the ISO transfer handling equivalent to that prior to that commit > to get back the original ISO performance numbers. > > Fixes: 08a36b543803 ("usb: dwc3: gadget: simplify __dwc3_gadget_ep_queue()") > Signed-off-by: Roger Quadros Any comments? > --- > drivers/usb/dwc3/gadget.c | 12 +++++++++++- > 1 file changed, 11 insertions(+), 1 deletion(-) > > diff --git a/drivers/usb/dwc3/gadget.c b/drivers/usb/dwc3/gadget.c > index 0d75158..8f71ccc 100644 > --- a/drivers/usb/dwc3/gadget.c > +++ b/drivers/usb/dwc3/gadget.c > @@ -1245,14 +1245,24 @@ static int __dwc3_gadget_ep_queue(struct dwc3_ep *dep, struct dwc3_request *req) > __dwc3_gadget_start_isoc(dwc, dep, cur_uf); > dep->flags &= ~DWC3_EP_PENDING_REQUEST; > } > + return 0; > } > - return 0; > + > + if ((dep->flags & DWC3_EP_BUSY) && > + !(dep->flags & DWC3_EP_MISSED_ISOC)) { > + WARN_ON_ONCE(!dep->resource_index); > + ret = __dwc3_gadget_kick_transfer(dep, > + dep->resource_index); > + } > + > + goto out; > } > > if (!dwc3_calc_trbs_left(dep)) > return 0; > > ret = __dwc3_gadget_kick_transfer(dep, 0); > +out: > if (ret == -EBUSY) > ret = 0; > > -- cheers, -roger