From patchwork Thu Feb 7 11:49:45 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Hans Verkuil X-Patchwork-Id: 54363 X-Patchwork-Delegate: hverkuil@xs4all.nl Received: from vger.kernel.org ([209.132.180.67]) by www.linuxtv.org with esmtp (Exim 4.84_2) (envelope-from ) id 1griBr-0006mm-QJ; Thu, 07 Feb 2019 11:50:00 +0000 Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727097AbfBGLty (ORCPT + 1 other); Thu, 7 Feb 2019 06:49:54 -0500 Received: from lb3-smtp-cloud8.xs4all.net ([194.109.24.29]:34405 "EHLO lb3-smtp-cloud8.xs4all.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727078AbfBGLtx (ORCPT ); Thu, 7 Feb 2019 06:49:53 -0500 Received: from test-nl.fritz.box ([80.101.105.217]) by smtp-cloud8.xs4all.net with ESMTPA id riBggvrMUNR5yriBig1Jmd; Thu, 07 Feb 2019 12:49:50 +0100 From: hverkuil-cisco@xs4all.nl To: linux-media@vger.kernel.org Cc: Michael Ira Krufky , Brad Love , Sakari Ailus , Hans Verkuil Subject: [RFC PATCH 5/8] v4l2-mem2mem: fix epoll() by calling poll_wait first Date: Thu, 7 Feb 2019 12:49:45 +0100 Message-Id: <20190207114948.37750-6-hverkuil-cisco@xs4all.nl> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190207114948.37750-1-hverkuil-cisco@xs4all.nl> References: <20190207114948.37750-1-hverkuil-cisco@xs4all.nl> MIME-Version: 1.0 X-CMAE-Envelope: MS4wfEiePhVJVg4gVkpx4rn8cwFm9GXweq0Bm9PHG20cjJAVw0PWeTWNnvjElmt11l3ppcqMSDvl6rAYAVgBF3rIFLu5WmNWi3wi1tfVmlMtYnc5wl/zUAhb aJTstGC/JGSgamc+4L7VZ6tH+lvxsFSgGMohx6qQ+brcB5NnA1iI884d+/tT8Zu51Zzf6s8HDUuZT0ZiA1GCGzNhXWO6tb4enCgAYpNOBXuD9OgWvzKhSKEd XxFnITfM5ssyZzKJugmXmN/KISHpN4ZrDUm0BfHYNsVsT8MP/mRX2HdYYq/Kg5fuDMV1sptWDDPjQ1pTM5VPL/GrtL6n6ldb3YdOmQhuzVo= Sender: linux-media-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org From: Hans Verkuil The epoll function expects that whenever the poll file op is called, the poll_wait function is also called. That didn't always happen in v4l2_m2m_poll(). Fix this, otherwise epoll() would timeout when it shouldn't. Signed-off-by: Hans Verkuil --- drivers/media/v4l2-core/v4l2-mem2mem.c | 19 +++++++------------ 1 file changed, 7 insertions(+), 12 deletions(-) diff --git a/drivers/media/v4l2-core/v4l2-mem2mem.c b/drivers/media/v4l2-core/v4l2-mem2mem.c index 631f4e2aa942..d97781b8ff88 100644 --- a/drivers/media/v4l2-core/v4l2-mem2mem.c +++ b/drivers/media/v4l2-core/v4l2-mem2mem.c @@ -617,20 +617,22 @@ __poll_t v4l2_m2m_poll(struct file *file, struct v4l2_m2m_ctx *m2m_ctx, __poll_t rc = 0; unsigned long flags; + src_q = v4l2_m2m_get_src_vq(m2m_ctx); + dst_q = v4l2_m2m_get_dst_vq(m2m_ctx); + + poll_wait(file, &src_q->done_wq, wait); + poll_wait(file, &dst_q->done_wq, wait); + if (test_bit(V4L2_FL_USES_V4L2_FH, &vfd->flags)) { struct v4l2_fh *fh = file->private_data; + poll_wait(file, &fh->wait, wait); if (v4l2_event_pending(fh)) rc = EPOLLPRI; - else if (req_events & EPOLLPRI) - poll_wait(file, &fh->wait, wait); if (!(req_events & (EPOLLOUT | EPOLLWRNORM | EPOLLIN | EPOLLRDNORM))) return rc; } - src_q = v4l2_m2m_get_src_vq(m2m_ctx); - dst_q = v4l2_m2m_get_dst_vq(m2m_ctx); - /* * There has to be at least one buffer queued on each queued_list, which * means either in driver already or waiting for driver to claim it @@ -642,11 +644,6 @@ __poll_t v4l2_m2m_poll(struct file *file, struct v4l2_m2m_ctx *m2m_ctx, goto end; } - spin_lock_irqsave(&src_q->done_lock, flags); - if (list_empty(&src_q->done_list)) - poll_wait(file, &src_q->done_wq, wait); - spin_unlock_irqrestore(&src_q->done_lock, flags); - spin_lock_irqsave(&dst_q->done_lock, flags); if (list_empty(&dst_q->done_list)) { /* @@ -657,8 +654,6 @@ __poll_t v4l2_m2m_poll(struct file *file, struct v4l2_m2m_ctx *m2m_ctx, spin_unlock_irqrestore(&dst_q->done_lock, flags); return rc | EPOLLIN | EPOLLRDNORM; } - - poll_wait(file, &dst_q->done_wq, wait); } spin_unlock_irqrestore(&dst_q->done_lock, flags);