[FFmpeg-cvslog] vulkan: take refs of frames using the regular buffer ref path

[Lynne]

ffmpeg | branch: master | Lynne <dev at lynne.ee> | Sat Mar  1 23:58:41 2025 +0100| [8631990f22b7c0637531916748daf18eea6d442c] | committer: Lynne

vulkan: take refs of frames using the regular buffer ref path

This simplifies the code, reduces allocations, and critically, does
not store references of frames, along with references to hw_frames_ctx.
The issue was that storing refs to frames while transferring stored
refs to hw_frames_ctx of frames, and so created a circular dependency,
which caused the Vulkan device to never be terminated.

This only stores what it strictly needs as a dependency, and enables
the frames context to be freed, even while doing asynchronous transfers.

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=8631990f22b7c0637531916748daf18eea6d442c
---

 libavutil/vulkan.c | 20 ++++++++++++++------
 1 file changed, 14 insertions(+), 6 deletions(-)

diff --git a/libavutil/vulkan.c b/libavutil/vulkan.c
index 1d18bf07c1..2ae619967a 100644
--- a/libavutil/vulkan.c
+++ b/libavutil/vulkan.c
@@ -538,8 +538,6 @@ void ff_vk_exec_discard_deps(FFVulkanContext *s, FFVkExecContext *e)
             e->frame_locked[j] = 0;
         }
         e->frame_update[j] = 0;
-        if (f->buf[0])
-            av_frame_free(&e->frame_deps[j]);
     }
     e->nb_frame_deps = 0;
 
@@ -700,6 +698,7 @@ int ff_vk_exec_add_dep_frame(FFVulkanContext *s, FFVkExecContext *e, AVFrame *f,
     uint8_t *frame_locked;
     uint8_t *frame_update;
     AVFrame **frame_deps;
+    AVBufferRef **buf_deps;
     VkImageLayout *layout_dst;
     uint32_t *queue_family_dst;
     VkAccessFlagBits *access_dst;
@@ -722,12 +721,21 @@ int ff_vk_exec_add_dep_frame(FFVulkanContext *s, FFVkExecContext *e, AVFrame *f,
     ARR_REALLOC(e, frame_update, &e->frame_update_alloc_size, e->nb_frame_deps);
     ARR_REALLOC(e, frame_deps,   &e->frame_deps_alloc_size,   e->nb_frame_deps);
 
-    e->frame_deps[e->nb_frame_deps] = f->buf[0] ? av_frame_clone(f) : f;
-    if (!e->frame_deps[e->nb_frame_deps]) {
-        ff_vk_exec_discard_deps(s, e);
-        return AVERROR(ENOMEM);
+    /* prepare_frame in hwcontext_vulkan.c uses the regular frame management
+     * code but has no frame yet, and it doesn't need to actually store a ref
+     * to the frame. */
+    if (f->buf[0]) {
+        ARR_REALLOC(e, buf_deps, &e->buf_deps_alloc_size, e->nb_buf_deps);
+        e->buf_deps[e->nb_buf_deps] = av_buffer_ref(f->buf[0]);
+        if (!e->buf_deps[e->nb_buf_deps]) {
+            ff_vk_exec_discard_deps(s, e);
+            return AVERROR(ENOMEM);
+        }
+        e->nb_buf_deps++;
     }
 
+    e->frame_deps[e->nb_frame_deps] = f;
+
     vkfc->lock_frame(hwfc, vkf);
     e->frame_locked[e->nb_frame_deps] = 1;
     e->frame_update[e->nb_frame_deps] = 0;