On Tue, Oct 31, 2023 at 05:31:01PM +0100, Benjamin Gaignard wrote:
> Improve __vb2_queue_free() and __vb2_free_mem() to free
> range of buffers and not only the last few buffers.
> Intoduce starting index to be flexible on range and change the loops
> according to this parameters.
>
> Signed-off-by: Benjamin Gaignard <benjamin.gaignard@collabora.com>
> ---
> .../media/common/videobuf2/videobuf2-core.c | 59 +++++++++----------
> 1 file changed, 28 insertions(+), 31 deletions(-)
>
> diff --git a/drivers/media/common/videobuf2/videobuf2-core.c b/drivers/media/common/videobuf2/videobuf2-core.c
> index 6e88406fcae9..010a8bca0240 100644
> --- a/drivers/media/common/videobuf2/videobuf2-core.c
> +++ b/drivers/media/common/videobuf2/videobuf2-core.c
> @@ -519,15 +519,13 @@ static int __vb2_queue_alloc(struct vb2_queue *q, enum vb2_memory memory,
> /*
> * __vb2_free_mem() - release all video buffer memory for a given queue
This comment is kind of outdated. Maybe we should replace it with
release video buffer memory for a given range of buffers in a given
queue
?
> */
> -static void __vb2_free_mem(struct vb2_queue *q, unsigned int buffers)
> +static void __vb2_free_mem(struct vb2_queue *q, unsigned int start, unsigned int count)
> {
> - unsigned int buffer;
> + unsigned int i;
> struct vb2_buffer *vb;
> - unsigned int q_num_buffers = vb2_get_num_buffers(q);
>
> - for (buffer = q_num_buffers - buffers; buffer < q_num_buffers;
> - ++buffer) {
> - vb = vb2_get_buffer(q, buffer);
> + for (i = start; i < q->max_num_buffers && i < start + count; i++) {
We could make this (and all those numerous simialr iterations) more
efficient by using bitmap helpers (probably wrapped in some vb2 helpers),
e.g. for_each_set_bit_from() (vb2_for_each_buffer_from()?). It can be done
in a follow up patch separately from this series though.
> + vb = vb2_get_buffer(q, i);
> if (!vb)
> continue;
>
> @@ -542,35 +540,35 @@ static void __vb2_free_mem(struct vb2_queue *q, unsigned int buffers)
> }
>
> /*
> - * __vb2_queue_free() - free buffers at the end of the queue - video memory and
> + * __vb2_queue_free() - free count buffers from start index of the queue - video memory and
nit: How about using the @count and @start notation to refer the argument
names? (Can be done with a follow up patch outside of this series later.)
> * related information, if no buffers are left return the queue to an
> * uninitialized state. Might be called even if the queue has already been freed.
> */
> -static void __vb2_queue_free(struct vb2_queue *q, unsigned int buffers)
> +static void __vb2_queue_free(struct vb2_queue *q, unsigned int start, unsigned int count)
> {
> - unsigned int buffer;
> - unsigned int q_num_buffers = vb2_get_num_buffers(q);
> + unsigned int i;
>
> lockdep_assert_held(&q->mmap_lock);
>
> /* Call driver-provided cleanup function for each buffer, if provided */
> - for (buffer = q_num_buffers - buffers; buffer < q_num_buffers;
> - ++buffer) {
> - struct vb2_buffer *vb = vb2_get_buffer(q, buffer);
> + for (i = start; i < q->max_num_buffers && i < start + count; i++) {
> + struct vb2_buffer *vb = vb2_get_buffer(q, i);
>
> - if (vb && vb->planes[0].mem_priv)
> + if (!vb)
> + continue;
> + if (vb->planes[0].mem_priv)
nit: Not sure if we really had to change this, but I'm fine with either.
Best regards,
Tomasz
@@ -519,15 +519,13 @@ static int __vb2_queue_alloc(struct vb2_queue *q, enum vb2_memory memory,
/*
* __vb2_free_mem() - release all video buffer memory for a given queue
*/
-static void __vb2_free_mem(struct vb2_queue *q, unsigned int buffers)
+static void __vb2_free_mem(struct vb2_queue *q, unsigned int start, unsigned int count)
{
- unsigned int buffer;
+ unsigned int i;
struct vb2_buffer *vb;
- unsigned int q_num_buffers = vb2_get_num_buffers(q);
- for (buffer = q_num_buffers - buffers; buffer < q_num_buffers;
- ++buffer) {
- vb = vb2_get_buffer(q, buffer);
+ for (i = start; i < q->max_num_buffers && i < start + count; i++) {
+ vb = vb2_get_buffer(q, i);
if (!vb)
continue;
@@ -542,35 +540,35 @@ static void __vb2_free_mem(struct vb2_queue *q, unsigned int buffers)
}
/*
- * __vb2_queue_free() - free buffers at the end of the queue - video memory and
+ * __vb2_queue_free() - free count buffers from start index of the queue - video memory and
* related information, if no buffers are left return the queue to an
* uninitialized state. Might be called even if the queue has already been freed.
*/
-static void __vb2_queue_free(struct vb2_queue *q, unsigned int buffers)
+static void __vb2_queue_free(struct vb2_queue *q, unsigned int start, unsigned int count)
{
- unsigned int buffer;
- unsigned int q_num_buffers = vb2_get_num_buffers(q);
+ unsigned int i;
lockdep_assert_held(&q->mmap_lock);
/* Call driver-provided cleanup function for each buffer, if provided */
- for (buffer = q_num_buffers - buffers; buffer < q_num_buffers;
- ++buffer) {
- struct vb2_buffer *vb = vb2_get_buffer(q, buffer);
+ for (i = start; i < q->max_num_buffers && i < start + count; i++) {
+ struct vb2_buffer *vb = vb2_get_buffer(q, i);
- if (vb && vb->planes[0].mem_priv)
+ if (!vb)
+ continue;
+ if (vb->planes[0].mem_priv)
call_void_vb_qop(vb, buf_cleanup, vb);
}
/* Release video buffer memory */
- __vb2_free_mem(q, buffers);
+ __vb2_free_mem(q, start, count);
#ifdef CONFIG_VIDEO_ADV_DEBUG
/*
* Check that all the calls were balanced during the life-time of this
* queue. If not then dump the counters to the kernel log.
*/
- if (q_num_buffers) {
+ 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;
@@ -596,8 +594,8 @@ static void __vb2_queue_free(struct vb2_queue *q, unsigned int buffers)
q->cnt_stop_streaming = 0;
q->cnt_unprepare_streaming = 0;
}
- for (buffer = 0; buffer < vb2_get_num_buffers(q); buffer++) {
- struct vb2_buffer *vb = vb2_get_buffer(q, buffer);
+ for (i = start; i < q->max_num_buffers && i < start + count; i++) {
+ struct vb2_buffer *vb = vb2_get_buffer(q, i);
bool unbalanced;
if (!vb)
@@ -614,7 +612,7 @@ static void __vb2_queue_free(struct vb2_queue *q, unsigned int buffers)
if (unbalanced) {
pr_info("unbalanced counters for queue %p, buffer %d:\n",
- q, buffer);
+ q, i);
if (vb->cnt_buf_init != vb->cnt_buf_cleanup)
pr_info(" buf_init: %u buf_cleanup: %u\n",
vb->cnt_buf_init, vb->cnt_buf_cleanup);
@@ -648,9 +646,8 @@ static void __vb2_queue_free(struct vb2_queue *q, unsigned int buffers)
#endif
/* Free vb2 buffers */
- for (buffer = q_num_buffers - buffers; buffer < q_num_buffers;
- ++buffer) {
- struct vb2_buffer *vb = vb2_get_buffer(q, buffer);
+ for (i = start; i < q->max_num_buffers && i < start + count; i++) {
+ struct vb2_buffer *vb = vb2_get_buffer(q, i);
if (!vb)
continue;
@@ -690,7 +687,7 @@ EXPORT_SYMBOL(vb2_buffer_in_use);
static bool __buffers_in_use(struct vb2_queue *q)
{
unsigned int buffer;
- for (buffer = 0; buffer < vb2_get_num_buffers(q); ++buffer) {
+ for (buffer = 0; buffer < q->max_num_buffers; ++buffer) {
struct vb2_buffer *vb = vb2_get_buffer(q, buffer);
if (!vb)
@@ -850,7 +847,7 @@ int vb2_core_reqbufs(struct vb2_queue *q, enum vb2_memory memory,
* queued without ever calling STREAMON.
*/
__vb2_queue_cancel(q);
- __vb2_queue_free(q, q_num_bufs);
+ __vb2_queue_free(q, 0, q->max_num_buffers);
mutex_unlock(&q->mmap_lock);
/*
@@ -960,7 +957,7 @@ int vb2_core_reqbufs(struct vb2_queue *q, enum vb2_memory memory,
* from already queued buffers and it will reset q->memory to
* VB2_MEMORY_UNKNOWN.
*/
- __vb2_queue_free(q, allocated_buffers);
+ __vb2_queue_free(q, first_index, allocated_buffers);
mutex_unlock(&q->mmap_lock);
return ret;
}
@@ -1000,7 +997,7 @@ int vb2_core_create_bufs(struct vb2_queue *q, enum vb2_memory memory,
bool no_previous_buffers = !q_num_bufs;
int ret = 0;
- if (q->num_buffers == q->max_num_buffers) {
+ if (q_num_bufs == q->max_num_buffers) {
dprintk(q, 1, "maximum number of buffers already allocated\n");
return -ENOBUFS;
}
@@ -1100,7 +1097,7 @@ int vb2_core_create_bufs(struct vb2_queue *q, enum vb2_memory memory,
* from already queued buffers and it will reset q->memory to
* VB2_MEMORY_UNKNOWN.
*/
- __vb2_queue_free(q, allocated_buffers);
+ __vb2_queue_free(q, *first_index, allocated_buffers);
mutex_unlock(&q->mmap_lock);
return -ENOMEM;
}
@@ -1714,7 +1711,7 @@ static int vb2_start_streaming(struct vb2_queue *q)
* Forcefully reclaim buffers if the driver did not
* correctly return them to vb2.
*/
- for (i = 0; i < vb2_get_num_buffers(q); ++i) {
+ for (i = 0; i < q->max_num_buffers; ++i) {
vb = vb2_get_buffer(q, i);
if (!vb)
@@ -2120,7 +2117,7 @@ static void __vb2_queue_cancel(struct vb2_queue *q)
* to vb2 in stop_streaming().
*/
if (WARN_ON(atomic_read(&q->owned_by_drv_count))) {
- for (i = 0; i < vb2_get_num_buffers(q); i++) {
+ for (i = 0; i < q->max_num_buffers; i++) {
struct vb2_buffer *vb = vb2_get_buffer(q, i);
if (!vb)
@@ -2164,7 +2161,7 @@ static void __vb2_queue_cancel(struct vb2_queue *q)
* call to __fill_user_buffer() after buf_finish(). That order can't
* be changed, so we can't move the buf_finish() to __vb2_dqbuf().
*/
- for (i = 0; i < vb2_get_num_buffers(q); i++) {
+ for (i = 0; i < q->max_num_buffers; i++) {
struct vb2_buffer *vb;
struct media_request *req;
@@ -2568,7 +2565,7 @@ void vb2_core_queue_release(struct vb2_queue *q)
__vb2_cleanup_fileio(q);
__vb2_queue_cancel(q);
mutex_lock(&q->mmap_lock);
- __vb2_queue_free(q, q->max_num_buffers);
+ __vb2_queue_free(q, 0, q->max_num_buffers);
kfree(q->bufs);
q->bufs = NULL;
bitmap_free(q->bufs_bitmap);