From patchwork Mon Jun 28 08:16:00 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Michael Grzeschik X-Patchwork-Id: 12347411 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=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT 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 8A3FDC49EA7 for ; Mon, 28 Jun 2021 08:16:19 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6F517619F1 for ; Mon, 28 Jun 2021 08:16:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232333AbhF1ISn (ORCPT ); Mon, 28 Jun 2021 04:18:43 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37452 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232103AbhF1ISk (ORCPT ); Mon, 28 Jun 2021 04:18:40 -0400 Received: from metis.ext.pengutronix.de (metis.ext.pengutronix.de [IPv6:2001:67c:670:201:290:27ff:fe1d:cc33]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 42A2CC061766 for ; Mon, 28 Jun 2021 01:16:15 -0700 (PDT) Received: from dude.hi.pengutronix.de ([2001:67c:670:100:1d::7]) by metis.ext.pengutronix.de with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1lxmRB-0006TK-IT; Mon, 28 Jun 2021 10:16:13 +0200 Received: from mgr by dude.hi.pengutronix.de with local (Exim 4.92) (envelope-from ) id 1lxmRB-0004Dj-4L; Mon, 28 Jun 2021 10:16:13 +0200 From: Michael Grzeschik To: linux-usb@vger.kernel.org Cc: laurent.pinchart@ideasonboard.com, caleb.connolly@ideasonboard.com, paul.elder@ideasonboard.com, balbi@kernel.org, kernel@pengutronix.de Subject: [PATCH v2 5/5] usb: gadget: uvc: decrease the interrupt load to a quarter Date: Mon, 28 Jun 2021 10:16:00 +0200 Message-Id: <20210628081600.14525-6-m.grzeschik@pengutronix.de> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20210628081600.14525-1-m.grzeschik@pengutronix.de> References: <20210628081600.14525-1-m.grzeschik@pengutronix.de> MIME-Version: 1.0 X-SA-Exim-Connect-IP: 2001:67c:670:100:1d::7 X-SA-Exim-Mail-From: mgr@pengutronix.de X-SA-Exim-Scanned: No (on metis.ext.pengutronix.de); SAEximRunCond expanded to false X-PTX-Original-Recipient: linux-usb@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org With usb3 we handle many more requests. Decrease the interrupt load by only enabling the interrupt every quarter of the allocated requests. Reviewed-by: Paul Elder Signed-off-by: Michael Grzeschik --- v1 -> v2: - edited patch description - removed extra parantheses - added a comment for the logic - using unsigned int instead of int - reinitializing req_int_count in uvcg_video_enable --- drivers/usb/gadget/function/uvc.h | 2 ++ drivers/usb/gadget/function/uvc_video.c | 16 ++++++++++++++++ 2 files changed, 18 insertions(+) diff --git a/drivers/usb/gadget/function/uvc.h b/drivers/usb/gadget/function/uvc.h index 36b78f8b3cd4c..255a61bd6a6a8 100644 --- a/drivers/usb/gadget/function/uvc.h +++ b/drivers/usb/gadget/function/uvc.h @@ -101,6 +101,8 @@ struct uvc_video { struct list_head req_free; spinlock_t req_lock; + unsigned int req_int_count; + void (*encode) (struct usb_request *req, struct uvc_video *video, struct uvc_buffer *buf); diff --git a/drivers/usb/gadget/function/uvc_video.c b/drivers/usb/gadget/function/uvc_video.c index 9910c2dc6168f..a1eec38280425 100644 --- a/drivers/usb/gadget/function/uvc_video.c +++ b/drivers/usb/gadget/function/uvc_video.c @@ -362,6 +362,19 @@ static void uvcg_video_pump(struct work_struct *work) video->encode(req, video, buf); + /* With usb3 we have more requests. This will decrease the + * interrupt load to a quarter but also catches the corner + * cases, which needs to be handled */ + if (list_empty(&video->req_free) || + buf->state == UVC_BUF_STATE_DONE || + !(video->req_int_count % + DIV_ROUND_UP(video->uvc_num_requests, 4))) { + video->req_int_count = 0; + req->no_interrupt = 0; + } else { + req->no_interrupt = 1; + } + /* Queue the USB request */ ret = uvcg_video_ep_queue(video, req); spin_unlock_irqrestore(&queue->irqlock, flags); @@ -370,6 +383,7 @@ static void uvcg_video_pump(struct work_struct *work) uvcg_queue_cancel(queue, 0); break; } + video->req_int_count++; } spin_lock_irqsave(&video->req_lock, flags); @@ -418,6 +432,8 @@ int uvcg_video_enable(struct uvc_video *video, int enable) video->encode = video->queue.use_sg ? uvc_video_encode_isoc_sg : uvc_video_encode_isoc; + video->req_int_count = 0; + schedule_work(&video->pump); return ret;