From: hverkuil-cisco@xs4all.nl
To: linux-media@vger.kernel.org
Cc: Michael Ira Krufky <mkrufky@linuxtv.org>,
Brad Love <brad@nextdimension.cc>,
Sakari Ailus <sakari.ailus@linux.intel.com>,
Hans Verkuil <hverkuil-cisco@xs4all.nl>
Subject: [RFC PATCH 8/8] dvb-core: fix epoll() by calling poll_wait first
Date: Thu, 7 Feb 2019 12:49:48 +0100 [thread overview]
Message-ID: <20190207114948.37750-9-hverkuil-cisco@xs4all.nl> (raw)
In-Reply-To: <20190207114948.37750-1-hverkuil-cisco@xs4all.nl>
From: Hans Verkuil <hverkuil-cisco@xs4all.nl>
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 dvb_demux_poll(), dvb_dvr_poll() and
dvb_ca_en50221_io_poll(). Fix this, otherwise epoll()
can timeout when it shouldn't.
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
---
drivers/media/dvb-core/dmxdev.c | 8 ++++----
drivers/media/dvb-core/dvb_ca_en50221.c | 5 ++---
2 files changed, 6 insertions(+), 7 deletions(-)
diff --git a/drivers/media/dvb-core/dmxdev.c b/drivers/media/dvb-core/dmxdev.c
index 1544e8cef564..f14a872d1268 100644
--- a/drivers/media/dvb-core/dmxdev.c
+++ b/drivers/media/dvb-core/dmxdev.c
@@ -1195,13 +1195,13 @@ static __poll_t dvb_demux_poll(struct file *file, poll_table *wait)
struct dmxdev_filter *dmxdevfilter = file->private_data;
__poll_t mask = 0;
+ poll_wait(file, &dmxdevfilter->buffer.queue, wait);
+
if ((!dmxdevfilter) || dmxdevfilter->dev->exit)
return EPOLLERR;
if (dvb_vb2_is_streaming(&dmxdevfilter->vb2_ctx))
return dvb_vb2_poll(&dmxdevfilter->vb2_ctx, file, wait);
- poll_wait(file, &dmxdevfilter->buffer.queue, wait);
-
if (dmxdevfilter->state != DMXDEV_STATE_GO &&
dmxdevfilter->state != DMXDEV_STATE_DONE &&
dmxdevfilter->state != DMXDEV_STATE_TIMEDOUT)
@@ -1346,13 +1346,13 @@ static __poll_t dvb_dvr_poll(struct file *file, poll_table *wait)
dprintk("%s\n", __func__);
+ poll_wait(file, &dmxdev->dvr_buffer.queue, wait);
+
if (dmxdev->exit)
return EPOLLERR;
if (dvb_vb2_is_streaming(&dmxdev->dvr_vb2_ctx))
return dvb_vb2_poll(&dmxdev->dvr_vb2_ctx, file, wait);
- poll_wait(file, &dmxdev->dvr_buffer.queue, wait);
-
if (((file->f_flags & O_ACCMODE) == O_RDONLY) ||
dmxdev->may_do_mmap) {
if (dmxdev->dvr_buffer.error)
diff --git a/drivers/media/dvb-core/dvb_ca_en50221.c b/drivers/media/dvb-core/dvb_ca_en50221.c
index 4d371cea0d5d..ebf1e3b03819 100644
--- a/drivers/media/dvb-core/dvb_ca_en50221.c
+++ b/drivers/media/dvb-core/dvb_ca_en50221.c
@@ -1797,6 +1797,8 @@ static __poll_t dvb_ca_en50221_io_poll(struct file *file, poll_table *wait)
dprintk("%s\n", __func__);
+ poll_wait(file, &ca->wait_queue, wait);
+
if (dvb_ca_en50221_io_read_condition(ca, &result, &slot) == 1)
mask |= EPOLLIN;
@@ -1804,9 +1806,6 @@ static __poll_t dvb_ca_en50221_io_poll(struct file *file, poll_table *wait)
if (mask)
return mask;
- /* wait for something to happen */
- poll_wait(file, &ca->wait_queue, wait);
-
if (dvb_ca_en50221_io_read_condition(ca, &result, &slot) == 1)
mask |= EPOLLIN;
--
2.20.1
next prev parent reply other threads:[~2019-02-07 11:49 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-02-07 11:49 [RFC PATCH 0/8] cec/mc/vb2/dvb: fix epoll support hverkuil-cisco
2019-02-07 11:49 ` [RFC PATCH 1/8] cec: fix epoll() by calling poll_wait first hverkuil-cisco
2019-02-08 20:53 ` Sean Young
2019-02-07 11:49 ` [RFC PATCH 2/8] media-request: " hverkuil-cisco
2019-02-07 11:49 ` [RFC PATCH 3/8] vb2: " hverkuil-cisco
2019-02-07 11:49 ` [RFC PATCH 4/8] v4l2-ctrls.c: " hverkuil-cisco
2019-02-07 11:49 ` [RFC PATCH 5/8] v4l2-mem2mem: " hverkuil-cisco
2019-02-07 11:49 ` [RFC PATCH 6/8] v4l2-mem2mem: add q->error check to v4l2_m2m_poll() hverkuil-cisco
2019-02-07 11:49 ` [RFC PATCH 7/8] videobuf: fix epoll() by calling poll_wait first hverkuil-cisco
2019-02-07 11:49 ` hverkuil-cisco [this message]
2019-02-08 21:12 ` [RFC PATCH 8/8] dvb-core: " Sean Young
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