poll method lose race condition
PATCH v2 1/1 poll method lose race condition
bttv-driver.c,cx23885-video.c,cx88-video.c: poll method lose race condition for capture video.
In v2, use the clear logic.Thanks to Trent Piepho's help.
Signed-off-by Figo.zhang <[email protected]>
--- drivers/media/video/bt8xx/bttv-driver.c | 20 ++++++++++++-------- drivers/media/video/cx23885/cx23885-video.c | 15 +++++++++++---- drivers/media/video/cx88/cx88-video.c | 15 +++++++++++---- 3 files changed, 34 insertions(+), 16 deletions(-)
drivers/media/video/bt8xx/bttv-driver.c +12 -8
@@ -3152,6 +3152,7 @@ static unsigned int bttv_poll(struct file *file, poll_table *wait)struct bttv_fh *fh = file->private_data;struct bttv_buffer *buf;enum v4l2_field field; +unsigned int rc =POLLERR ;if (V4L2_BUF_TYPE_VBI_CAPTURE == fh->type) {if (!check_alloc_btres (fh->btv,fh,RESOURCE_VBI ))
@@ -3160,9 +3161,10 @@ static unsigned int bttv_poll(struct file *file, poll_table *wait) }if (check_btres (fh,RESOURCE_VIDEO_STREAM )) { +mutex_lock (&fh->cap.vb_lock);/* streaming capture */ if (list_empty (&fh->cap.stream)) -return POLLERR ; +return done; buf = list_entry(fh->cap.stream.next,struct bttv_buffer,vb.stream); }else {/* read() capture */
@@ -3170,16 +3172,16 @@ static unsigned int bttv_poll(struct file *file, poll_table *wait)if (NULL == fh->cap.read_buf) {/* need to capture a new frame */ if (locked_btres (fh->btv,RESOURCE_VIDEO_STREAM )) - goto err; + goto done; fh->cap.read_buf =videobuf_sg_alloc (fh->cap.msize);if (NULL == fh->cap.read_buf) - goto err; + goto done; fh->cap.read_buf->memory =V4L2_MEMORY_USERPTR ; field =videobuf_next_field (&fh->cap);if (0 != fh->cap.ops->buf_prepare (&fh->cap,fh->cap.read_buf,field)) {kfree (fh->cap.read_buf); fh->cap.read_buf =NULL ; - goto err; + goto done; } fh->cap.ops->buf_queue (&fh->cap,fh->cap.read_buf); fh->cap.read_off =0 ;
@@ -3191,11 +3193,13 @@ static unsigned int bttv_poll(struct file *file, poll_table *wait)poll_wait (file, &buf->vb.done, wait);if (buf->vb.state ==VIDEOBUF_DONE || buf->vb.state ==VIDEOBUF_ERROR ) -return POLLIN |POLLRDNORM ; -return 0 ; -err: + rc =POLLIN |POLLRDNORM ; +else + rc =0 ; + +done:mutex_unlock (&fh->cap.vb_lock); -return POLLERR ; +return rc; }static int bttv_open (struct file *file)
drivers/media/video/cx23885/cx23885-video.c +11 -4
@@ -796,6 +796,7 @@ static unsigned int video_poll(struct file *file, {struct cx23885_fh *fh = file->private_data;struct cx23885_buffer *buf; +unsigned int rc =POLLERR ;if (V4L2_BUF_TYPE_VBI_CAPTURE == fh->type) {if (!res_get (fh->dev, fh,RESOURCE_VBI ))
@@ -803,23 +804,29 @@ static unsigned int video_poll(struct file *file,return videobuf_poll_stream (file, &fh->vbiq, wait); } +mutex_lock (&fh->vidq.vb_lock);if (res_check (fh,RESOURCE_VIDEO )) {/* streaming capture */ if (list_empty (&fh->vidq.stream)) -return POLLERR ; + goto done; buf =list_entry (fh->vidq.stream.next, struct cx23885_buffer, vb.stream); }else {/* read() capture */ buf = (struct cx23885_buffer *)fh->vidq.read_buf;if (NULL == buf) -return POLLERR ; + goto done; }poll_wait (file, &buf->vb.done, wait);if (buf->vb.state ==VIDEOBUF_DONE || buf->vb.state ==VIDEOBUF_ERROR ) -return POLLIN |POLLRDNORM ; -return 0 ; + rc =POLLIN |POLLRDNORM ; +else + rc =0 ; + +done: +mutex_unlock (&fh->vidq.vb_lock); +return rc; }static int video_release (struct file *file)
drivers/media/video/cx88/cx88-video.c +11 -4
@@ -869,6 +869,7 @@ video_poll(struct file *file, struct poll_table_struct *wait) {struct cx8800_fh *fh = file->private_data;struct cx88_buffer *buf; +unsigned int rc =POLLERR ;if (V4L2_BUF_TYPE_VBI_CAPTURE == fh->type) {if (!res_get (fh->dev,fh,RESOURCE_VBI ))
@@ -876,22 +877,28 @@ video_poll(struct file *file, struct poll_table_struct *wait)return videobuf_poll_stream (file, &fh->vbiq, wait); } +mutex_lock (&fh->vidq.vb_lock);if (res_check (fh,RESOURCE_VIDEO )) {/* streaming capture */ if (list_empty (&fh->vidq.stream)) -return POLLERR ; + goto done; buf = list_entry(fh->vidq.stream.next,struct cx88_buffer,vb.stream); }else {/* read() capture */ buf = (struct cx88_buffer *)fh->vidq.read_buf;if (NULL == buf) -return POLLERR ; + goto done; }poll_wait (file, &buf->vb.done, wait);if (buf->vb.state ==VIDEOBUF_DONE || buf->vb.state ==VIDEOBUF_ERROR ) -return POLLIN |POLLRDNORM ; -return 0 ; + rc =POLLIN |POLLRDNORM ; +else + rc =0 ; + +done: +mutex_unlock (&fh->vidq.vb_lock); +return rc; }static int video_release (struct file *file)
A message that is not in the archive (sent off-list or not yet received): [email protected]
hi Mauro,
is it ok for this v2?
Best Regards,
Figo.zhang
Quoted 194 lines
2009/6/1 Figo.zhang <[email protected]>
bttv-driver.c,cx23885-video.c,cx88-video.c: poll method lose race condition for capture video. In v2, use the clear logic.Thanks to Trent Piepho's help. Signed-off-by: Figo.zhang <[email protected]> --- drivers/media/video/bt8xx/bttv-driver.c | 20 ++++++++++++-------- drivers/media/video/cx23885/cx23885-video.c | 15 +++++++++++---- drivers/media/video/cx88/cx88-video.c | 15 +++++++++++---- 3 files changed, 34 insertions(+), 16 deletions(-) diff --git a/drivers/media/video/bt8xx/bttv-driver.c b/drivers/media/video/bt8xx/bttv-driver.c index 23b7499..8d20528 100644 --- a/drivers/media/video/bt8xx/bttv-driver.c +++ b/drivers/media/video/bt8xx/bttv-driver.c @@ -3152,6 +3152,7 @@ static unsigned int bttv_poll(struct file *file, poll_table *wait) struct bttv_fh *fh = file->private_data; struct bttv_buffer *buf; enum v4l2_field field; + unsigned int rc = POLLERR; if (V4L2_BUF_TYPE_VBI_CAPTURE == fh->type) { if (! check_alloc_btres(fh->btv,fh,RESOURCE_VBI)) @@ -3160,9 +3161,10 @@ static unsigned int bttv_poll(struct file *file, poll_table *wait) } if (check_btres(fh,RESOURCE_VIDEO_STREAM)) { + mutex_lock(&fh->cap.vb_lock); /* streaming capture */ if (list_empty(&fh->cap.stream)) - return POLLERR; + return done; buf = list_entry(fh->cap.stream.next,struct bttv_buffer,vb.stream); } else { /* read() capture */ @@ -3170,16 +3172,16 @@ static unsigned int bttv_poll(struct file *file, poll_table *wait) if (NULL == fh->cap.read_buf) { /* need to capture a new frame */ if (locked_btres(fh->btv,RESOURCE_VIDEO_STREAM)) - goto err; + goto done; fh->cap.read_buf = videobuf_sg_alloc(fh->cap.msize); if (NULL == fh->cap.read_buf) - goto err; + goto done; fh->cap.read_buf->memory = V4L2_MEMORY_USERPTR; field = videobuf_next_field(&fh->cap); if (0 != fh->cap.ops->buf_prepare(&fh->cap,fh->cap.read_buf,field)) { kfree (fh->cap.read_buf); fh->cap.read_buf = NULL; - goto err; + goto done; } fh->cap.ops->buf_queue(&fh->cap,fh->cap.read_buf); fh->cap.read_off = 0; @@ -3191,11 +3193,13 @@ static unsigned int bttv_poll(struct file *file, poll_table *wait) poll_wait(file, &buf->vb.done, wait); if (buf->vb.state == VIDEOBUF_DONE || buf->vb.state == VIDEOBUF_ERROR) - return POLLIN|POLLRDNORM; - return 0; -err: + rc = POLLIN|POLLRDNORM; + else + rc = 0; + +done: mutex_unlock(&fh->cap.vb_lock); - return POLLERR; + return rc; } static int bttv_open(struct file *file) diff --git a/drivers/media/video/cx23885/cx23885-video.c b/drivers/media/video/cx23885/cx23885-video.c index 68068c6..f542493 100644 --- a/drivers/media/video/cx23885/cx23885-video.c +++ b/drivers/media/video/cx23885/cx23885-video.c @@ -796,6 +796,7 @@ static unsigned int video_poll(struct file *file, { struct cx23885_fh *fh = file->private_data; struct cx23885_buffer *buf; + unsigned int rc = POLLERR; if (V4L2_BUF_TYPE_VBI_CAPTURE == fh->type) { if (!res_get(fh->dev, fh, RESOURCE_VBI)) @@ -803,23 +804,29 @@ static unsigned int video_poll(struct file *file, return videobuf_poll_stream(file, &fh->vbiq, wait); } + mutex_lock(&fh->vidq.vb_lock); if (res_check(fh, RESOURCE_VIDEO)) { /* streaming capture */ if (list_empty(&fh->vidq.stream)) - return POLLERR; + goto done; buf = list_entry(fh->vidq.stream.next, struct cx23885_buffer, vb.stream); } else { /* read() capture */ buf = (struct cx23885_buffer *)fh->vidq.read_buf; if (NULL == buf) - return POLLERR; + goto done; } poll_wait(file, &buf->vb.done, wait); if (buf->vb.state == VIDEOBUF_DONE || buf->vb.state == VIDEOBUF_ERROR) - return POLLIN|POLLRDNORM; - return 0; + rc = POLLIN|POLLRDNORM; + else + rc = 0; + +done: + mutex_unlock(&fh->vidq.vb_lock); + return rc; } static int video_release(struct file *file) diff --git a/drivers/media/video/cx88/cx88-video.c b/drivers/media/video/cx88/cx88-video.c index b993d42..b1ca54b 100644 --- a/drivers/media/video/cx88/cx88-video.c +++ b/drivers/media/video/cx88/cx88-video.c @@ -869,6 +869,7 @@ video_poll(struct file *file, struct poll_table_struct *wait) { struct cx8800_fh *fh = file->private_data; struct cx88_buffer *buf; + unsigned int rc = POLLERR; if (V4L2_BUF_TYPE_VBI_CAPTURE == fh->type) { if (!res_get(fh->dev,fh,RESOURCE_VBI)) @@ -876,22 +877,28 @@ video_poll(struct file *file, struct poll_table_struct *wait) return videobuf_poll_stream(file, &fh->vbiq, wait); } + mutex_lock(&fh->vidq.vb_lock); if (res_check(fh,RESOURCE_VIDEO)) { /* streaming capture */ if (list_empty(&fh->vidq.stream)) - return POLLERR; + goto done; buf = list_entry(fh->vidq.stream.next,struct cx88_buffer,vb.stream); } else { /* read() capture */ buf = (struct cx88_buffer*)fh->vidq.read_buf; if (NULL == buf) - return POLLERR; + goto done; } poll_wait(file, &buf->vb.done, wait); if (buf->vb.state == VIDEOBUF_DONE || buf->vb.state == VIDEOBUF_ERROR) - return POLLIN|POLLRDNORM; - return 0; + rc = POLLIN|POLLRDNORM; + else + rc = 0; + +done: + mutex_unlock(&fh->vidq.vb_lock); + return rc; } static int video_release(struct file *file)
Em Mon, 01 Jun 2009 10:05:04 +0800
"Figo.zhang" <[email protected]> escreveu:
Quoted 24 lines
bttv-driver.c,cx23885-video.c,cx88-video.c: poll method lose race condition for capture video.
In v2, use the clear logic.Thanks to Trent Piepho's help.
Signed-off-by Figo.zhang <[email protected]>--- drivers/media/video/bt8xx/bttv-driver.c | 20 ++++++++++++-------- drivers/media/video/cx23885/cx23885-video.c | 15 +++++++++++---- drivers/media/video/cx88/cx88-video.c | 15 +++++++++++---- 3 files changed, 34 insertions(+), 16 deletions(-)drivers/media/video/bt8xx/bttv-driver.c +1
-0@@ -3152,6 +3152,7 @@ static unsigned int bttv_poll(struct file *file, poll_table *wait)struct bttv_fh *fh = file->private_data;struct bttv_buffer *buf;enum v4l2_field field; +unsigned int rc =POLLERR ;if (V4L2_BUF_TYPE_VBI_CAPTURE == fh->type) {if (!check_alloc_btres (fh->btv,fh,RESOURCE_VBI ))
drivers/media/video/bt8xx/bttv-driver.c static unsigned int bttv_poll(struct file *file, poll_table *wait) · line 3167
Quoted 8 lines
drivers/media/video/bt8xx/bttv-driver.c +2
-1@@ -3160,9 +3161,10 @@ static unsigned int bttv_poll(struct file *file, poll_table *wait) }if (check_btres (fh,RESOURCE_VIDEO_STREAM )) { +mutex_lock (&fh->cap.vb_lock);/* streaming capture */ if (list_empty (&fh->cap.stream)) -return POLLERR ; +return done;
Here, you're keeping the mutex locked. Maybe you wanted to do a "goto done" ?
Quoted 138 lines
drivers/media/video/bt8xx/bttv-driver.c +9
-7buf = list_entry(fh->cap.stream.next,struct bttv_buffer,vb.stream); }else {/* read() capture */ @@ -3170,16 +3172,16 @@ static unsigned int bttv_poll(struct file *file, poll_table *wait)if (NULL == fh->cap.read_buf) {/* need to capture a new frame */ if (locked_btres (fh->btv,RESOURCE_VIDEO_STREAM )) - goto err; + goto done; fh->cap.read_buf =videobuf_sg_alloc (fh->cap.msize);if (NULL == fh->cap.read_buf) - goto err; + goto done; fh->cap.read_buf->memory =V4L2_MEMORY_USERPTR ; field =videobuf_next_field (&fh->cap);if (0 != fh->cap.ops->buf_prepare (&fh->cap,fh->cap.read_buf,field)) {kfree (fh->cap.read_buf); fh->cap.read_buf =NULL ; - goto err; + goto done; } fh->cap.ops->buf_queue (&fh->cap,fh->cap.read_buf); fh->cap.read_off =0 ;@@ -3191,11 +3193,13 @@ static unsigned int bttv_poll(struct file *file, poll_table *wait)poll_wait (file, &buf->vb.done, wait);if (buf->vb.state ==VIDEOBUF_DONE || buf->vb.state ==VIDEOBUF_ERROR ) -return POLLIN |POLLRDNORM ; -return 0 ; -err: + rc =POLLIN |POLLRDNORM ; +else + rc =0 ; + +done:mutex_unlock (&fh->cap.vb_lock); -return POLLERR ; +return rc; }static int bttv_open (struct file *file)drivers/media/video/cx23885/cx23885-video.c +11
-4@@ -796,6 +796,7 @@ static unsigned int video_poll(struct file *file, {struct cx23885_fh *fh = file->private_data;struct cx23885_buffer *buf; +unsigned int rc =POLLERR ;if (V4L2_BUF_TYPE_VBI_CAPTURE == fh->type) {if (!res_get (fh->dev, fh,RESOURCE_VBI ))@@ -803,23 +804,29 @@ static unsigned int video_poll(struct file *file,return videobuf_poll_stream (file, &fh->vbiq, wait); } +mutex_lock (&fh->vidq.vb_lock);if (res_check (fh,RESOURCE_VIDEO )) {/* streaming capture */ if (list_empty (&fh->vidq.stream)) -return POLLERR ; + goto done; buf =list_entry (fh->vidq.stream.next, struct cx23885_buffer, vb.stream); }else {/* read() capture */ buf = (struct cx23885_buffer *)fh->vidq.read_buf;if (NULL == buf) -return POLLERR ; + goto done; }poll_wait (file, &buf->vb.done, wait);if (buf->vb.state ==VIDEOBUF_DONE || buf->vb.state ==VIDEOBUF_ERROR ) -return POLLIN |POLLRDNORM ; -return 0 ; + rc =POLLIN |POLLRDNORM ; +else + rc =0 ; + +done: +mutex_unlock (&fh->vidq.vb_lock); +return rc; }static int video_release (struct file *file)drivers/media/video/cx88/cx88-video.c +11
-5@@ -869,6 +869,7 @@ video_poll(struct file *file, struct poll_table_struct *wait) {struct cx8800_fh *fh = file->private_data;struct cx88_buffer *buf; +unsigned int rc =POLLERR ;if (V4L2_BUF_TYPE_VBI_CAPTURE == fh->type) {if (!res_get (fh->dev,fh,RESOURCE_VBI ))@@ -876,22 +877,28 @@ video_poll(struct file *file, struct poll_table_struct *wait)return videobuf_poll_stream (file, &fh->vbiq, wait); } +mutex_lock (&fh->vidq.vb_lock);if (res_check (fh,RESOURCE_VIDEO )) {/* streaming capture */ if (list_empty (&fh->vidq.stream)) -return POLLERR ; + goto done; buf = list_entry(fh->vidq.stream.next,struct cx88_buffer,vb.stream); }else {/* read() capture */ buf = (struct cx88_buffer *)fh->vidq.read_buf;if (NULL == buf) -return POLLERR ; + goto done; }poll_wait (file, &buf->vb.done, wait);if (buf->vb.state ==VIDEOBUF_DONE || buf->vb.state ==VIDEOBUF_ERROR ) -return POLLIN |POLLRDNORM ; -return 0 ; + rc =POLLIN |POLLRDNORM ; +else + rc =0 ; + +done: +mutex_unlock (&fh->vidq.vb_lock); +return rc; }static int video_release (struct file *file) --To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to [email protected]
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Signature · 2 lines
Cheers, Mauro