| Message ID | 20240119094944.26763-5-benjamin.gaignard@collabora.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Add DELETE_BUF ioctl | expand |
On 19/01/2024 10:49, Benjamin Gaignard wrote: > Add a bitmap field to know which of bufs array entries are > used or not. > Remove no more used num_buffers field from queue structure. > Use bitmap_find_next_zero_area() to find the first possible > range when creating new buffers to fill the gaps. > If no suitable range is found try to allocate less buffers > than requested. > > Signed-off-by: Benjamin Gaignard <benjamin.gaignard@collabora.com> > --- > version 17: > - allow to allocate less buffers than requested in __vb2_queue_alloc() > when using bitmap. > - add vb2_core_allocated_queue_buffers_storage() and > vb2_core_free_queue_buffers_storage() to avoid duplicate code. > .../media/common/videobuf2/videobuf2-core.c | 71 ++++++++++++++----- > include/media/videobuf2-core.h | 18 +++-- > 2 files changed, 64 insertions(+), 25 deletions(-) > > diff --git a/drivers/media/common/videobuf2/videobuf2-core.c b/drivers/media/common/videobuf2/videobuf2-core.c > index fd5ac2845018..45cbdfaf72b5 100644 > --- a/drivers/media/common/videobuf2/videobuf2-core.c > +++ b/drivers/media/common/videobuf2/videobuf2-core.c > @@ -421,11 +421,12 @@ static void init_buffer_cache_hints(struct vb2_queue *q, struct vb2_buffer *vb) > */ > static void vb2_queue_add_buffer(struct vb2_queue *q, struct vb2_buffer *vb, unsigned int index) > { > - WARN_ON(index >= q->max_num_buffers || q->bufs[index] || vb->vb2_queue); > + WARN_ON(index >= q->max_num_buffers || test_bit(index, q->bufs_bitmap) || vb->vb2_queue); > > q->bufs[index] = vb; > vb->index = index; > vb->vb2_queue = q; > + set_bit(index, q->bufs_bitmap); > } > > /** > @@ -434,6 +435,7 @@ static void vb2_queue_add_buffer(struct vb2_queue *q, struct vb2_buffer *vb, uns > */ > static void vb2_queue_remove_buffer(struct vb2_buffer *vb) > { > + clear_bit(vb->index, vb->vb2_queue->bufs_bitmap); > vb->vb2_queue->bufs[vb->index] = NULL; > vb->vb2_queue = NULL; > } > @@ -452,9 +454,9 @@ static int __vb2_queue_alloc(struct vb2_queue *q, enum vb2_memory memory, > const unsigned int plane_sizes[VB2_MAX_PLANES], > unsigned int *first_index) > { > - unsigned int q_num_buffers = vb2_get_num_buffers(q); > unsigned int buffer, plane; > struct vb2_buffer *vb; > + unsigned long index = 0; 0 -> q->max_num_buffers This ensure an error occurs in case num_buffers == 0 (which it should never be, but you never know) with the 'while' code suggested below. > int ret; > > /* > @@ -462,9 +464,25 @@ static int __vb2_queue_alloc(struct vb2_queue *q, enum vb2_memory memory, > * in the queue is below q->max_num_buffers > */ > num_buffers = min_t(unsigned int, num_buffers, > - q->max_num_buffers - q_num_buffers); > + q->max_num_buffers - vb2_get_num_buffers(q)); > + > +again: > + index = bitmap_find_next_zero_area(q->bufs_bitmap, q->max_num_buffers, > + 0, num_buffers, 0); > + > + /* Try to find free space for less buffers */ > + if (index >= q->max_num_buffers && num_buffers) { > + num_buffers--; > + goto again; > + } Hmm, this is really just a: while (num_buffers) { index = bitmap_find_next_zero_area(q->bufs_bitmap, q->max_num_buffers, 0, num_buffers, 0); if (index < q->max_num_buffers) break; /* Try to find free space for less buffers */ num_buffers--; } This avoids the ugly goto. > > - *first_index = q_num_buffers; > + /* If there is no space left to allocate buffers return 0 to indicate the error */ > + if (index >= q->max_num_buffers) { > + *first_index = 0; > + return 0; > + } > + > + *first_index = index; > > for (buffer = 0; buffer < num_buffers; ++buffer) { > /* Allocate vb2 buffer structures */ > @@ -484,7 +502,7 @@ static int __vb2_queue_alloc(struct vb2_queue *q, enum vb2_memory memory, > vb->planes[plane].min_length = plane_sizes[plane]; > } > > - vb2_queue_add_buffer(q, vb, q_num_buffers + buffer); > + vb2_queue_add_buffer(q, vb, index++); > call_void_bufop(q, init_buffer, vb); > > /* Allocate video buffer memory for the MMAP type */ > @@ -664,7 +682,6 @@ static void __vb2_queue_free(struct vb2_queue *q, unsigned int buffers) > kfree(vb); > } > > - q->num_buffers -= buffers; > if (!vb2_get_num_buffers(q)) { > q->memory = VB2_MEMORY_UNKNOWN; > INIT_LIST_HEAD(&q->queued_list); > @@ -818,6 +835,32 @@ static bool verify_coherency_flags(struct vb2_queue *q, bool non_coherent_mem) > return true; > } > > +static int vb2_core_allocated_queue_buffers_storage(struct vb2_queue *q) I think vb2_core_allocate_buffers_storage is a better name. > +{ > + if (!q->bufs) > + q->bufs = kcalloc(q->max_num_buffers, sizeof(*q->bufs), GFP_KERNEL); > + if (!q->bufs) > + return -ENOMEM; > + > + if (!q->bufs_bitmap) > + q->bufs_bitmap = bitmap_zalloc(q->max_num_buffers, GFP_KERNEL); > + if (!q->bufs_bitmap) { > + kfree(q->bufs); > + q->bufs = NULL; > + return -ENOMEM; > + } > + > + return 0; > +} > + > +static void vb2_core_free_queue_buffers_storage(struct vb2_queue *q) Drop the "_queue" part here as well. > +{ > + kfree(q->bufs); > + q->bufs = NULL; > + bitmap_free(q->bufs_bitmap); > + q->bufs_bitmap = NULL; > +} > + > int vb2_core_reqbufs(struct vb2_queue *q, enum vb2_memory memory, > unsigned int flags, unsigned int *count) > { > @@ -878,10 +921,7 @@ int vb2_core_reqbufs(struct vb2_queue *q, enum vb2_memory memory, > * in the queue_setup op. > */ > mutex_lock(&q->mmap_lock); > - if (!q->bufs) > - q->bufs = kcalloc(q->max_num_buffers, sizeof(*q->bufs), GFP_KERNEL); > - if (!q->bufs) > - ret = -ENOMEM; > + ret = vb2_core_allocated_queue_buffers_storage(q); > q->memory = memory; > mutex_unlock(&q->mmap_lock); > if (ret) > @@ -953,7 +993,6 @@ int vb2_core_reqbufs(struct vb2_queue *q, enum vb2_memory memory, > } > > mutex_lock(&q->mmap_lock); > - q->num_buffers = allocated_buffers; > > if (ret < 0) { > /* > @@ -980,6 +1019,7 @@ int vb2_core_reqbufs(struct vb2_queue *q, enum vb2_memory memory, > mutex_lock(&q->mmap_lock); > q->memory = VB2_MEMORY_UNKNOWN; > mutex_unlock(&q->mmap_lock); > + vb2_core_free_queue_buffers_storage(q); > return ret; > } > EXPORT_SYMBOL_GPL(vb2_core_reqbufs); > @@ -1013,11 +1053,8 @@ int vb2_core_create_bufs(struct vb2_queue *q, enum vb2_memory memory, > * value in the queue_setup op. > */ > mutex_lock(&q->mmap_lock); > + ret = vb2_core_allocated_queue_buffers_storage(q); > q->memory = memory; > - if (!q->bufs) > - q->bufs = kcalloc(q->max_num_buffers, sizeof(*q->bufs), GFP_KERNEL); > - if (!q->bufs) > - ret = -ENOMEM; > mutex_unlock(&q->mmap_lock); > if (ret) > return ret; > @@ -1080,7 +1117,6 @@ int vb2_core_create_bufs(struct vb2_queue *q, enum vb2_memory memory, > } > > mutex_lock(&q->mmap_lock); > - q->num_buffers += allocated_buffers; > > if (ret < 0) { > /* > @@ -2579,8 +2615,7 @@ void vb2_core_queue_release(struct vb2_queue *q) > __vb2_queue_cancel(q); > mutex_lock(&q->mmap_lock); > __vb2_queue_free(q, vb2_get_num_buffers(q)); > - kfree(q->bufs); > - q->bufs = NULL; > + vb2_core_free_queue_buffers_storage(q); > mutex_unlock(&q->mmap_lock); > } > EXPORT_SYMBOL_GPL(vb2_core_queue_release); > diff --git a/include/media/videobuf2-core.h b/include/media/videobuf2-core.h > index e29ff77814d3..8647eee348bd 100644 > --- a/include/media/videobuf2-core.h > +++ b/include/media/videobuf2-core.h > @@ -346,8 +346,8 @@ struct vb2_buffer { > * describes the requested number of planes and sizes\[\] > * contains the requested plane sizes. In this case > * \*num_buffers are being allocated additionally to > - * q->num_buffers. If either \*num_planes or the requested > - * sizes are invalid callback must return %-EINVAL. > + * 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 > @@ -571,8 +571,9 @@ struct vb2_buf_ops { > * @mmap_lock: private mutex used when buffers are allocated/freed/mmapped > * @memory: current memory type used > * @dma_dir: DMA mapping direction. > - * @bufs: videobuf2 buffer structures > - * @num_buffers: number of allocated/used buffers > + * @bufs: videobuf2 buffer structures. If it is non-NULL then > + * bufs_bitmap is also non-NULL. > + * @bufs_bitmap: bitmap tracking whether each bufs[] entry is used > * @max_num_buffers: upper limit of number of allocated/used buffers. > * If set to 0 v4l2 core will change it VB2_MAX_FRAME > * for backward compatibility. > @@ -639,7 +640,7 @@ struct vb2_queue { > unsigned int memory; > enum dma_data_direction dma_dir; > struct vb2_buffer **bufs; > - unsigned int num_buffers; > + unsigned long *bufs_bitmap; > unsigned int max_num_buffers; > > struct list_head queued_list; > @@ -1168,7 +1169,10 @@ static inline bool vb2_fileio_is_active(struct vb2_queue *q) > */ > static inline unsigned int vb2_get_num_buffers(struct vb2_queue *q) > { > - return q->num_buffers; > + if (q->bufs_bitmap) > + return bitmap_weight(q->bufs_bitmap, q->max_num_buffers); > + > + return 0; > } > > /** > @@ -1277,7 +1281,7 @@ static inline struct vb2_buffer *vb2_get_buffer(struct vb2_queue *q, > if (index >= q->max_num_buffers) > return NULL; > > - if (index < q->num_buffers) > + if (test_bit(index, q->bufs_bitmap)) > return q->bufs[index]; > return NULL; > } Regards, Hans
diff --git a/drivers/media/common/videobuf2/videobuf2-core.c b/drivers/media/common/videobuf2/videobuf2-core.c index fd5ac2845018..45cbdfaf72b5 100644 --- a/drivers/media/common/videobuf2/videobuf2-core.c +++ b/drivers/media/common/videobuf2/videobuf2-core.c @@ -421,11 +421,12 @@ static void init_buffer_cache_hints(struct vb2_queue *q, struct vb2_buffer *vb) */ static void vb2_queue_add_buffer(struct vb2_queue *q, struct vb2_buffer *vb, unsigned int index) { - WARN_ON(index >= q->max_num_buffers || q->bufs[index] || vb->vb2_queue); + WARN_ON(index >= q->max_num_buffers || test_bit(index, q->bufs_bitmap) || vb->vb2_queue); q->bufs[index] = vb; vb->index = index; vb->vb2_queue = q; + set_bit(index, q->bufs_bitmap); } /** @@ -434,6 +435,7 @@ static void vb2_queue_add_buffer(struct vb2_queue *q, struct vb2_buffer *vb, uns */ static void vb2_queue_remove_buffer(struct vb2_buffer *vb) { + clear_bit(vb->index, vb->vb2_queue->bufs_bitmap); vb->vb2_queue->bufs[vb->index] = NULL; vb->vb2_queue = NULL; } @@ -452,9 +454,9 @@ static int __vb2_queue_alloc(struct vb2_queue *q, enum vb2_memory memory, const unsigned int plane_sizes[VB2_MAX_PLANES], unsigned int *first_index) { - unsigned int q_num_buffers = vb2_get_num_buffers(q); unsigned int buffer, plane; struct vb2_buffer *vb; + unsigned long index = 0; int ret; /* @@ -462,9 +464,25 @@ static int __vb2_queue_alloc(struct vb2_queue *q, enum vb2_memory memory, * in the queue is below q->max_num_buffers */ num_buffers = min_t(unsigned int, num_buffers, - q->max_num_buffers - q_num_buffers); + q->max_num_buffers - vb2_get_num_buffers(q)); + +again: + index = bitmap_find_next_zero_area(q->bufs_bitmap, q->max_num_buffers, + 0, num_buffers, 0); + + /* Try to find free space for less buffers */ + if (index >= q->max_num_buffers && num_buffers) { + num_buffers--; + goto again; + } - *first_index = q_num_buffers; + /* If there is no space left to allocate buffers return 0 to indicate the error */ + if (index >= q->max_num_buffers) { + *first_index = 0; + return 0; + } + + *first_index = index; for (buffer = 0; buffer < num_buffers; ++buffer) { /* Allocate vb2 buffer structures */ @@ -484,7 +502,7 @@ static int __vb2_queue_alloc(struct vb2_queue *q, enum vb2_memory memory, vb->planes[plane].min_length = plane_sizes[plane]; } - vb2_queue_add_buffer(q, vb, q_num_buffers + buffer); + vb2_queue_add_buffer(q, vb, index++); call_void_bufop(q, init_buffer, vb); /* Allocate video buffer memory for the MMAP type */ @@ -664,7 +682,6 @@ static void __vb2_queue_free(struct vb2_queue *q, unsigned int buffers) kfree(vb); } - q->num_buffers -= buffers; if (!vb2_get_num_buffers(q)) { q->memory = VB2_MEMORY_UNKNOWN; INIT_LIST_HEAD(&q->queued_list); @@ -818,6 +835,32 @@ static bool verify_coherency_flags(struct vb2_queue *q, bool non_coherent_mem) return true; } +static int vb2_core_allocated_queue_buffers_storage(struct vb2_queue *q) +{ + if (!q->bufs) + q->bufs = kcalloc(q->max_num_buffers, sizeof(*q->bufs), GFP_KERNEL); + if (!q->bufs) + return -ENOMEM; + + if (!q->bufs_bitmap) + q->bufs_bitmap = bitmap_zalloc(q->max_num_buffers, GFP_KERNEL); + if (!q->bufs_bitmap) { + kfree(q->bufs); + q->bufs = NULL; + return -ENOMEM; + } + + return 0; +} + +static void vb2_core_free_queue_buffers_storage(struct vb2_queue *q) +{ + kfree(q->bufs); + q->bufs = NULL; + bitmap_free(q->bufs_bitmap); + q->bufs_bitmap = NULL; +} + int vb2_core_reqbufs(struct vb2_queue *q, enum vb2_memory memory, unsigned int flags, unsigned int *count) { @@ -878,10 +921,7 @@ int vb2_core_reqbufs(struct vb2_queue *q, enum vb2_memory memory, * in the queue_setup op. */ mutex_lock(&q->mmap_lock); - if (!q->bufs) - q->bufs = kcalloc(q->max_num_buffers, sizeof(*q->bufs), GFP_KERNEL); - if (!q->bufs) - ret = -ENOMEM; + ret = vb2_core_allocated_queue_buffers_storage(q); q->memory = memory; mutex_unlock(&q->mmap_lock); if (ret) @@ -953,7 +993,6 @@ int vb2_core_reqbufs(struct vb2_queue *q, enum vb2_memory memory, } mutex_lock(&q->mmap_lock); - q->num_buffers = allocated_buffers; if (ret < 0) { /* @@ -980,6 +1019,7 @@ int vb2_core_reqbufs(struct vb2_queue *q, enum vb2_memory memory, mutex_lock(&q->mmap_lock); q->memory = VB2_MEMORY_UNKNOWN; mutex_unlock(&q->mmap_lock); + vb2_core_free_queue_buffers_storage(q); return ret; } EXPORT_SYMBOL_GPL(vb2_core_reqbufs); @@ -1013,11 +1053,8 @@ int vb2_core_create_bufs(struct vb2_queue *q, enum vb2_memory memory, * value in the queue_setup op. */ mutex_lock(&q->mmap_lock); + ret = vb2_core_allocated_queue_buffers_storage(q); q->memory = memory; - if (!q->bufs) - q->bufs = kcalloc(q->max_num_buffers, sizeof(*q->bufs), GFP_KERNEL); - if (!q->bufs) - ret = -ENOMEM; mutex_unlock(&q->mmap_lock); if (ret) return ret; @@ -1080,7 +1117,6 @@ int vb2_core_create_bufs(struct vb2_queue *q, enum vb2_memory memory, } mutex_lock(&q->mmap_lock); - q->num_buffers += allocated_buffers; if (ret < 0) { /* @@ -2579,8 +2615,7 @@ void vb2_core_queue_release(struct vb2_queue *q) __vb2_queue_cancel(q); mutex_lock(&q->mmap_lock); __vb2_queue_free(q, vb2_get_num_buffers(q)); - kfree(q->bufs); - q->bufs = NULL; + vb2_core_free_queue_buffers_storage(q); mutex_unlock(&q->mmap_lock); } EXPORT_SYMBOL_GPL(vb2_core_queue_release); diff --git a/include/media/videobuf2-core.h b/include/media/videobuf2-core.h index e29ff77814d3..8647eee348bd 100644 --- a/include/media/videobuf2-core.h +++ b/include/media/videobuf2-core.h @@ -346,8 +346,8 @@ struct vb2_buffer { * describes the requested number of planes and sizes\[\] * contains the requested plane sizes. In this case * \*num_buffers are being allocated additionally to - * q->num_buffers. If either \*num_planes or the requested - * sizes are invalid callback must return %-EINVAL. + * 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 @@ -571,8 +571,9 @@ struct vb2_buf_ops { * @mmap_lock: private mutex used when buffers are allocated/freed/mmapped * @memory: current memory type used * @dma_dir: DMA mapping direction. - * @bufs: videobuf2 buffer structures - * @num_buffers: number of allocated/used buffers + * @bufs: videobuf2 buffer structures. If it is non-NULL then + * bufs_bitmap is also non-NULL. + * @bufs_bitmap: bitmap tracking whether each bufs[] entry is used * @max_num_buffers: upper limit of number of allocated/used buffers. * If set to 0 v4l2 core will change it VB2_MAX_FRAME * for backward compatibility. @@ -639,7 +640,7 @@ struct vb2_queue { unsigned int memory; enum dma_data_direction dma_dir; struct vb2_buffer **bufs; - unsigned int num_buffers; + unsigned long *bufs_bitmap; unsigned int max_num_buffers; struct list_head queued_list; @@ -1168,7 +1169,10 @@ static inline bool vb2_fileio_is_active(struct vb2_queue *q) */ static inline unsigned int vb2_get_num_buffers(struct vb2_queue *q) { - return q->num_buffers; + if (q->bufs_bitmap) + return bitmap_weight(q->bufs_bitmap, q->max_num_buffers); + + return 0; } /** @@ -1277,7 +1281,7 @@ static inline struct vb2_buffer *vb2_get_buffer(struct vb2_queue *q, if (index >= q->max_num_buffers) return NULL; - if (index < q->num_buffers) + if (test_bit(index, q->bufs_bitmap)) return q->bufs[index]; return NULL; }
Add a bitmap field to know which of bufs array entries are used or not. Remove no more used num_buffers field from queue structure. Use bitmap_find_next_zero_area() to find the first possible range when creating new buffers to fill the gaps. If no suitable range is found try to allocate less buffers than requested. Signed-off-by: Benjamin Gaignard <benjamin.gaignard@collabora.com> --- version 17: - allow to allocate less buffers than requested in __vb2_queue_alloc() when using bitmap. - add vb2_core_allocated_queue_buffers_storage() and vb2_core_free_queue_buffers_storage() to avoid duplicate code. .../media/common/videobuf2/videobuf2-core.c | 71 ++++++++++++++----- include/media/videobuf2-core.h | 18 +++-- 2 files changed, 64 insertions(+), 25 deletions(-)