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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 39268C25B47 for ; Fri, 27 Oct 2023 07:20:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1345342AbjJ0HUB (ORCPT ); Fri, 27 Oct 2023 03:20:01 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51110 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231233AbjJ0HUA (ORCPT ); Fri, 27 Oct 2023 03:20:00 -0400 Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 46E90194 for ; Fri, 27 Oct 2023 00:19:58 -0700 (PDT) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 7146FC433C7; Fri, 27 Oct 2023 07:19:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1698391197; bh=eAzGncuNN+h/nEmL0ZN/dcXM9fGW6dn1TaiHf0175Cw=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=nOPH7MxC1fgBZD4Sr2OY9INWba7SOjh03byjzEY0Hg3jA6SPPpqqHDuT4zAnESK0o STR/y3RVFPBeVW+1Gu7xEUbXIGNhlWS/0jsqyKjR2j2QvR9z999NEiYDcuEdQFSlcv gURLO0OKq7yCHZDh3THAX4hJIsBmzZD3aqYa+BI0= Date: Fri, 27 Oct 2023 09:19:54 +0200 From: Greg KH To: Jayant Chowdhary Cc: mgr@pengutronix.de, Thinh.Nguyen@synopsys.com, arakesh@google.com, etalvala@google.com, dan.scally@ideasonboard.com, laurent.pinchart@ideasonboard.com, linux-kernel@vger.kernel.org, linux-usb@vger.kernel.org, Michael Grzeschik Subject: Re: [PATCH v2] usb:gadget:uvc Do not use worker thread to pump usb requests Message-ID: <2023102739-reproach-salute-0d22@gregkh> References: <20231026215635.2478767-1-jchowdhary@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20231026215635.2478767-1-jchowdhary@google.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Oct 26, 2023 at 09:56:35PM +0000, Jayant Chowdhary wrote: > This patch is based on top of > https://lore.kernel.org/linux-usb/20230930184821.310143-1-arakesh@google.com/T/#t: That doesn't work in the changelog of a patch at all, it goes below the --- line p lease. > > When we use an async work queue to perform the function of pumping > usb requests to the usb controller, it is possible that thread scheduling > affects at what cadence we're able to pump requests. This could mean usb > requests miss their uframes - resulting in video stream flickers on the host > device. > > In this patch, we move the pumping of usb requests to > 1) uvcg_video_complete() complete handler for both isoc + bulk > endpoints. We still send 0 length requests when there is no uvc buffer > available to encode. > 2) uvc_v4l2_qbuf - only for bulk endpoints since it is not legal to send > 0 length requests. > > Signed-off-by: Michael Grzeschik > Signed-off-by: Jayant Chowdhary > Suggested-by: Jayant Chowdhary > Suggested-by: Avichal Rakesh > Tested-by: Jayant Chowdhary > --- > v1->v2: Fix code style and add self Signed-off-by Great, but as signed-off-by kind of implies you tested it, no need for the tested-by now, right? Not a big deal, and normally I'd ignore it but I know you at least have to do one more version of this based on the above problem... thanks, greg k-h