From patchwork Thu Nov 29 09:00:48 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Paul Kocialkowski X-Patchwork-Id: 10704201 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id AA3F61057 for ; Thu, 29 Nov 2018 09:01:54 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 96AAC2ECDC for ; Thu, 29 Nov 2018 09:01:54 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 8A3FA2ECE0; Thu, 29 Nov 2018 09:01:54 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.9 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id F108D2ECDB for ; Thu, 29 Nov 2018 09:01:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727245AbeK2UGa (ORCPT ); Thu, 29 Nov 2018 15:06:30 -0500 Received: from mail.bootlin.com ([62.4.15.54]:34635 "EHLO mail.bootlin.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726579AbeK2UGa (ORCPT ); Thu, 29 Nov 2018 15:06:30 -0500 Received: by mail.bootlin.com (Postfix, from userid 110) id 64BAD20CFA; Thu, 29 Nov 2018 10:01:49 +0100 (CET) Received: from localhost.localdomain (aaubervilliers-681-1-63-158.w90-88.abo.wanadoo.fr [90.88.18.158]) by mail.bootlin.com (Postfix) with ESMTPSA id 08003209AB; Thu, 29 Nov 2018 10:01:39 +0100 (CET) From: Paul Kocialkowski To: linux-media@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Cc: Maxime Ripard , Paul Kocialkowski , Mauro Carvalho Chehab , Greg Kroah-Hartman , Chen-Yu Tsai , Hans Verkuil , Sakari Ailus , Thomas Petazzoni , Ezequiel Garcia Subject: [PATCH v2 1/1] media: cedrus: Remove global IRQ spin lock from the driver Date: Thu, 29 Nov 2018 10:00:48 +0100 Message-Id: <20181129090048.16482-2-paul.kocialkowski@bootlin.com> X-Mailer: git-send-email 2.19.1 In-Reply-To: <20181129090048.16482-1-paul.kocialkowski@bootlin.com> References: <20181129090048.16482-1-paul.kocialkowski@bootlin.com> MIME-Version: 1.0 Sender: linux-media-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP We initially introduced a spin lock to ensure that the VPU registers are not accessed concurrently between our setup function and IRQ handler. The V4L2 M2M API ensures that only one decoding job runs at a time, so the interrupt signaling the end of decoding will not occur while the next picture is being configured. Spurious interrupts are taken care of in the handler, by checking that we have a valid M2M context and a decoding status available before marking the buffers as done. In addition, holding a spin lock could be problematic if non-atomic operations are required in the setup process for future codec support. As a result, remove the global IRQ spin lock. Signed-off-by: Paul Kocialkowski Acked-by: Maxime Ripard --- drivers/staging/media/sunxi/cedrus/cedrus.c | 1 - drivers/staging/media/sunxi/cedrus/cedrus.h | 2 -- drivers/staging/media/sunxi/cedrus/cedrus_dec.c | 9 --------- drivers/staging/media/sunxi/cedrus/cedrus_hw.c | 13 +------------ drivers/staging/media/sunxi/cedrus/cedrus_video.c | 5 ----- 5 files changed, 1 insertion(+), 29 deletions(-) diff --git a/drivers/staging/media/sunxi/cedrus/cedrus.c b/drivers/staging/media/sunxi/cedrus/cedrus.c index f7f46fbc2bcf..928edc01bc46 100644 --- a/drivers/staging/media/sunxi/cedrus/cedrus.c +++ b/drivers/staging/media/sunxi/cedrus/cedrus.c @@ -281,7 +281,6 @@ static int cedrus_probe(struct platform_device *pdev) dev->dec_ops[CEDRUS_CODEC_MPEG2] = &cedrus_dec_ops_mpeg2; mutex_init(&dev->dev_mutex); - spin_lock_init(&dev->irq_lock); ret = v4l2_device_register(&pdev->dev, &dev->v4l2_dev); if (ret) { diff --git a/drivers/staging/media/sunxi/cedrus/cedrus.h b/drivers/staging/media/sunxi/cedrus/cedrus.h index 3f61248c57ac..3acfdcf83691 100644 --- a/drivers/staging/media/sunxi/cedrus/cedrus.h +++ b/drivers/staging/media/sunxi/cedrus/cedrus.h @@ -105,8 +105,6 @@ struct cedrus_dev { /* Device file mutex */ struct mutex dev_mutex; - /* Interrupt spinlock */ - spinlock_t irq_lock; void __iomem *base; diff --git a/drivers/staging/media/sunxi/cedrus/cedrus_dec.c b/drivers/staging/media/sunxi/cedrus/cedrus_dec.c index e40180a33951..6c5e310a7cf7 100644 --- a/drivers/staging/media/sunxi/cedrus/cedrus_dec.c +++ b/drivers/staging/media/sunxi/cedrus/cedrus_dec.c @@ -28,7 +28,6 @@ void cedrus_device_run(void *priv) struct cedrus_dev *dev = ctx->dev; struct cedrus_run run = { 0 }; struct media_request *src_req; - unsigned long flags; run.src = v4l2_m2m_next_src_buf(ctx->fh.m2m_ctx); run.dst = v4l2_m2m_next_dst_buf(ctx->fh.m2m_ctx); @@ -39,8 +38,6 @@ void cedrus_device_run(void *priv) if (src_req) v4l2_ctrl_request_setup(src_req, &ctx->hdl); - spin_lock_irqsave(&ctx->dev->irq_lock, flags); - switch (ctx->src_fmt.pixelformat) { case V4L2_PIX_FMT_MPEG2_SLICE: run.mpeg2.slice_params = cedrus_find_control_data(ctx, @@ -55,16 +52,10 @@ void cedrus_device_run(void *priv) dev->dec_ops[ctx->current_codec]->setup(ctx, &run); - spin_unlock_irqrestore(&ctx->dev->irq_lock, flags); - /* Complete request(s) controls if needed. */ if (src_req) v4l2_ctrl_request_complete(src_req, &ctx->hdl); - spin_lock_irqsave(&ctx->dev->irq_lock, flags); - dev->dec_ops[ctx->current_codec]->trigger(ctx); - - spin_unlock_irqrestore(&ctx->dev->irq_lock, flags); } diff --git a/drivers/staging/media/sunxi/cedrus/cedrus_hw.c b/drivers/staging/media/sunxi/cedrus/cedrus_hw.c index 32adbcbe6175..0662906aab57 100644 --- a/drivers/staging/media/sunxi/cedrus/cedrus_hw.c +++ b/drivers/staging/media/sunxi/cedrus/cedrus_hw.c @@ -122,24 +122,17 @@ static irqreturn_t cedrus_irq(int irq, void *data) struct vb2_v4l2_buffer *src_buf, *dst_buf; enum vb2_buffer_state state; enum cedrus_irq_status status; - unsigned long flags; - - spin_lock_irqsave(&dev->irq_lock, flags); ctx = v4l2_m2m_get_curr_priv(dev->m2m_dev); if (!ctx) { v4l2_err(&dev->v4l2_dev, "Instance released before the end of transaction\n"); - spin_unlock_irqrestore(&dev->irq_lock, flags); - return IRQ_NONE; } status = dev->dec_ops[ctx->current_codec]->irq_status(ctx); - if (status == CEDRUS_IRQ_NONE) { - spin_unlock_irqrestore(&dev->irq_lock, flags); + if (status == CEDRUS_IRQ_NONE) return IRQ_NONE; - } dev->dec_ops[ctx->current_codec]->irq_disable(ctx); dev->dec_ops[ctx->current_codec]->irq_clear(ctx); @@ -150,8 +143,6 @@ static irqreturn_t cedrus_irq(int irq, void *data) if (!src_buf || !dst_buf) { v4l2_err(&dev->v4l2_dev, "Missing source and/or destination buffers\n"); - spin_unlock_irqrestore(&dev->irq_lock, flags); - return IRQ_HANDLED; } @@ -163,8 +154,6 @@ static irqreturn_t cedrus_irq(int irq, void *data) v4l2_m2m_buf_done(src_buf, state); v4l2_m2m_buf_done(dst_buf, state); - spin_unlock_irqrestore(&dev->irq_lock, flags); - return IRQ_WAKE_THREAD; } diff --git a/drivers/staging/media/sunxi/cedrus/cedrus_video.c b/drivers/staging/media/sunxi/cedrus/cedrus_video.c index 5c5fce678b93..8721b4a7d496 100644 --- a/drivers/staging/media/sunxi/cedrus/cedrus_video.c +++ b/drivers/staging/media/sunxi/cedrus/cedrus_video.c @@ -380,18 +380,13 @@ static void cedrus_queue_cleanup(struct vb2_queue *vq, u32 state) { struct cedrus_ctx *ctx = vb2_get_drv_priv(vq); struct vb2_v4l2_buffer *vbuf; - unsigned long flags; for (;;) { - spin_lock_irqsave(&ctx->dev->irq_lock, flags); - if (V4L2_TYPE_IS_OUTPUT(vq->type)) vbuf = v4l2_m2m_src_buf_remove(ctx->fh.m2m_ctx); else vbuf = v4l2_m2m_dst_buf_remove(ctx->fh.m2m_ctx); - spin_unlock_irqrestore(&ctx->dev->irq_lock, flags); - if (!vbuf) return;