media: vb2: drop wait_prepare/finish callbacks

Drop the wait_prepare/finish callbacks. Instead require that the vb2_queue
lock field is always set and use that lock when waiting for buffers to
arrive.

Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
This commit is contained in:
Hans Verkuil 2025-06-05 08:57:39 +02:00 committed by Mauro Carvalho Chehab
parent d0730006da
commit b70886ff58
3 changed files with 15 additions and 59 deletions

View file

@ -42,8 +42,6 @@ nitpick_ignore = [
("c:func", "struct fd_set"),
("c:func", "struct pollfd"),
("c:func", "usb_make_path"),
("c:func", "wait_finish"),
("c:func", "wait_prepare"),
("c:func", "write"),
("c:type", "atomic_t"),

View file

@ -605,8 +605,7 @@ static void __vb2_queue_free(struct vb2_queue *q, unsigned int start, unsigned i
*/
if (vb2_get_num_buffers(q)) {
bool unbalanced = q->cnt_start_streaming != q->cnt_stop_streaming ||
q->cnt_prepare_streaming != q->cnt_unprepare_streaming ||
q->cnt_wait_prepare != q->cnt_wait_finish;
q->cnt_prepare_streaming != q->cnt_unprepare_streaming;
if (unbalanced) {
pr_info("unbalanced counters for queue %p:\n", q);
@ -617,13 +616,8 @@ static void __vb2_queue_free(struct vb2_queue *q, unsigned int start, unsigned i
if (q->cnt_prepare_streaming != q->cnt_unprepare_streaming)
pr_info(" prepare_streaming: %u unprepare_streaming: %u\n",
q->cnt_prepare_streaming, q->cnt_unprepare_streaming);
if (q->cnt_wait_prepare != q->cnt_wait_finish)
pr_info(" wait_prepare: %u wait_finish: %u\n",
q->cnt_wait_prepare, q->cnt_wait_finish);
}
q->cnt_queue_setup = 0;
q->cnt_wait_prepare = 0;
q->cnt_wait_finish = 0;
q->cnt_prepare_streaming = 0;
q->cnt_start_streaming = 0;
q->cnt_stop_streaming = 0;
@ -2037,10 +2031,7 @@ static int __vb2_wait_for_done_vb(struct vb2_queue *q, int nonblocking)
* become ready or for streamoff. Driver's lock is released to
* allow streamoff or qbuf to be called while waiting.
*/
if (q->ops->wait_prepare)
call_void_qop(q, wait_prepare, q);
else if (q->lock)
mutex_unlock(q->lock);
mutex_unlock(q->lock);
/*
* All locks have been released, it is safe to sleep now.
@ -2050,10 +2041,7 @@ static int __vb2_wait_for_done_vb(struct vb2_queue *q, int nonblocking)
!list_empty(&q->done_list) || !q->streaming ||
q->error);
if (q->ops->wait_finish)
call_void_qop(q, wait_finish, q);
else if (q->lock)
mutex_lock(q->lock);
mutex_lock(q->lock);
q->waiting_in_dqbuf = 0;
/*
@ -2653,12 +2641,8 @@ int vb2_core_queue_init(struct vb2_queue *q)
if (WARN_ON(q->min_reqbufs_allocation > q->max_num_buffers))
return -EINVAL;
/* Either both or none are set */
if (WARN_ON(!q->ops->wait_prepare ^ !q->ops->wait_finish))
return -EINVAL;
/* Warn if q->lock is NULL and no custom wait_prepare is provided */
if (WARN_ON(!q->lock && !q->ops->wait_prepare))
/* Warn if q->lock is NULL */
if (WARN_ON(!q->lock))
return -EINVAL;
INIT_LIST_HEAD(&q->queued_list);
@ -3220,17 +3204,10 @@ static int vb2_thread(void *data)
continue;
prequeue--;
} else {
if (!threadio->stop) {
if (q->ops->wait_finish)
call_void_qop(q, wait_finish, q);
else if (q->lock)
mutex_lock(q->lock);
mutex_lock(q->lock);
if (!threadio->stop)
ret = vb2_core_dqbuf(q, &index, NULL, 0);
if (q->ops->wait_prepare)
call_void_qop(q, wait_prepare, q);
else if (q->lock)
mutex_unlock(q->lock);
}
mutex_unlock(q->lock);
dprintk(q, 5, "file io: vb2_dqbuf result: %d\n", ret);
if (!ret)
vb = vb2_get_buffer(q, index);
@ -3245,15 +3222,9 @@ static int vb2_thread(void *data)
if (copy_timestamp)
vb->timestamp = ktime_get_ns();
if (!threadio->stop) {
if (q->ops->wait_finish)
call_void_qop(q, wait_finish, q);
else if (q->lock)
mutex_lock(q->lock);
mutex_lock(q->lock);
ret = vb2_core_qbuf(q, vb, NULL, NULL);
if (q->ops->wait_prepare)
call_void_qop(q, wait_prepare, q);
else if (q->lock)
mutex_unlock(q->lock);
mutex_unlock(q->lock);
}
if (ret || threadio->stop)
break;

View file

@ -351,13 +351,6 @@ struct vb2_buffer {
* \*num_buffers are being allocated additionally to
* the buffers already allocated. If either \*num_planes
* or the requested sizes are invalid callback must return %-EINVAL.
* @wait_prepare: release any locks taken while calling vb2 functions;
* it is called before an ioctl needs to wait for a new
* buffer to arrive; required to avoid a deadlock in
* blocking access type.
* @wait_finish: reacquire all locks released in the previous callback;
* required to continue operation after sleeping while
* waiting for a new buffer to arrive.
* @buf_out_validate: called when the output buffer is prepared or queued
* to a request; drivers can use this to validate
* userspace-provided information; this is required only
@ -436,9 +429,6 @@ struct vb2_ops {
unsigned int *num_buffers, unsigned int *num_planes,
unsigned int sizes[], struct device *alloc_devs[]);
void (*wait_prepare)(struct vb2_queue *q);
void (*wait_finish)(struct vb2_queue *q);
int (*buf_out_validate)(struct vb2_buffer *vb);
int (*buf_init)(struct vb2_buffer *vb);
int (*buf_prepare)(struct vb2_buffer *vb);
@ -521,10 +511,10 @@ struct vb2_buf_ops {
* @non_coherent_mem: when set queue will attempt to allocate buffers using
* non-coherent memory.
* @lock: pointer to a mutex that protects the &struct vb2_queue. The
* driver can set this to a mutex to let the v4l2 core serialize
* the queuing ioctls. If the driver wants to handle locking
* itself, then this should be set to NULL. This lock is not used
* by the videobuf2 core API.
* driver must set this to a mutex to let the v4l2 core serialize
* the queuing ioctls. This lock is used when waiting for a new
* buffer to arrive: the lock is released, we wait for the new
* buffer, and then retaken.
* @owner: The filehandle that 'owns' the buffers, i.e. the filehandle
* that called reqbufs, create_buffers or started fileio.
* This field is not used by the videobuf2 core API, but it allows
@ -680,8 +670,6 @@ struct vb2_queue {
* called. Used to check for unbalanced ops.
*/
u32 cnt_queue_setup;
u32 cnt_wait_prepare;
u32 cnt_wait_finish;
u32 cnt_prepare_streaming;
u32 cnt_start_streaming;
u32 cnt_stop_streaming;
@ -766,8 +754,7 @@ void vb2_discard_done(struct vb2_queue *q);
* @q: pointer to &struct vb2_queue with videobuf2 queue.
*
* This function will wait until all buffers that have been given to the driver
* by &vb2_ops->buf_queue are given back to vb2 with vb2_buffer_done(). It
* doesn't call &vb2_ops->wait_prepare/&vb2_ops->wait_finish pair.
* by &vb2_ops->buf_queue are given back to vb2 with vb2_buffer_done().
* It is intended to be called with all locks taken, for example from
* &vb2_ops->stop_streaming callback.
*/