hwcontext_vulkan: actually use the frames exec context for prep/import/export

This was never actually used, likely due to confusion, as the device context
also had one used for uploads and downloads.
Also, since we're only using it for very quick image barriers (which are
practically free on all hardware), use the compute queue instead of the
transfer queue.

libavutil/hwcontext_vulkan.c

@@ -87,7 +87,8 @@ typedef struct VulkanDevicePriv {
 } VulkanDevicePriv;
 
 typedef struct VulkanFramesPriv {
-    VulkanExecCtx cmd;
+    /* Image conversions */
+    VulkanExecCtx conv_ctx;
 } VulkanFramesPriv;
 
 typedef struct AVVkFrameInternal {
@@ -1634,6 +1635,7 @@ static AVBufferRef *vulkan_pool_alloc(void *opaque, int size)
     AVHWFramesContext *hwfc = opaque;
     AVVulkanFramesContext *hwctx = hwfc->hwctx;
     VulkanDevicePriv *p = hwfc->device_ctx->internal->priv;
+    VulkanFramesPriv *fp = hwfc->internal->priv;
     VkExportMemoryAllocateInfo eminfo[AV_NUM_DATA_POINTERS];
     VkExternalMemoryHandleTypeFlags e = 0x0;
 
@@ -1665,7 +1667,7 @@ static AVBufferRef *vulkan_pool_alloc(void *opaque, int size)
     if (err)
         goto fail;
 
-    err = prepare_frame(hwfc, &p->cmd, f, PREP_MODE_WRITE);
+    err = prepare_frame(hwfc, &fp->conv_ctx, f, PREP_MODE_WRITE);
     if (err)
         goto fail;
 
@@ -1685,7 +1687,7 @@ static void vulkan_frames_uninit(AVHWFramesContext *hwfc)
 {
     VulkanFramesPriv *fp = hwfc->internal->priv;
 
-    free_exec_ctx(hwfc->device_ctx, &fp->cmd);
+    free_exec_ctx(hwfc->device_ctx, &fp->conv_ctx);
 }
 
 static int vulkan_frames_init(AVHWFramesContext *hwfc)
@@ -1703,9 +1705,9 @@ static int vulkan_frames_init(AVHWFramesContext *hwfc)
 
     hwctx->usage |= DEFAULT_USAGE_FLAGS;
 
-    err = create_exec_ctx(hwfc->device_ctx, &fp->cmd,
-                          dev_hwctx->queue_family_tx_index,
-                          GET_QUEUE_COUNT(dev_hwctx, 0, 0, 1));
+    err = create_exec_ctx(hwfc->device_ctx, &fp->conv_ctx,
+                          dev_hwctx->queue_family_comp_index,
+                          GET_QUEUE_COUNT(dev_hwctx, 0, 1, 0));
     if (err)
         return err;
 
@@ -1713,7 +1715,7 @@ static int vulkan_frames_init(AVHWFramesContext *hwfc)
     err = create_frame(hwfc, &f, hwctx->tiling, hwctx->usage,
                        hwctx->create_pnext);
     if (err) {
-        free_exec_ctx(hwfc->device_ctx, &p->cmd);
+        free_exec_ctx(hwfc->device_ctx, &fp->conv_ctx);
         return err;
     }
 
@@ -1726,7 +1728,7 @@ static int vulkan_frames_init(AVHWFramesContext *hwfc)
                                                              hwfc, vulkan_pool_alloc,
                                                              NULL);
         if (!hwfc->internal->pool_internal) {
-            free_exec_ctx(hwfc->device_ctx, &p->cmd);
+            free_exec_ctx(hwfc->device_ctx, &fp->conv_ctx);
             return AVERROR(ENOMEM);
         }
     }
@@ -1940,6 +1942,7 @@ static int vulkan_map_from_drm_frame_desc(AVHWFramesContext *hwfc, AVVkFrame **f
     AVHWDeviceContext *ctx = hwfc->device_ctx;
     AVVulkanDeviceContext *hwctx = ctx->hwctx;
     VulkanDevicePriv *p = ctx->internal->priv;
+    VulkanFramesPriv *fp = hwfc->internal->priv;
     const AVPixFmtDescriptor *fmt_desc = av_pix_fmt_desc_get(hwfc->sw_format);
     const int has_modifiers = p->extensions & EXT_DRM_MODIFIER_FLAGS;
     VkSubresourceLayout plane_data[AV_NUM_DATA_POINTERS] = { 0 };
@@ -2109,7 +2112,7 @@ static int vulkan_map_from_drm_frame_desc(AVHWFramesContext *hwfc, AVVkFrame **f
     /* NOTE: This is completely uneccesary and unneeded once we can import
      * semaphores from DRM. Otherwise we have to activate the semaphores.
      * We're reusing the exec context that's also used for uploads/downloads. */
-    err = prepare_frame(hwfc, &p->cmd, f, PREP_MODE_RO_SHADER);
+    err = prepare_frame(hwfc, &fp->conv_ctx, f, PREP_MODE_RO_SHADER);
     if (err)
         goto fail;
 
@@ -2469,6 +2472,7 @@ static int vulkan_map_to_drm(AVHWFramesContext *hwfc, AVFrame *dst,
     VkResult ret;
     AVVkFrame *f = (AVVkFrame *)src->data[0];
     VulkanDevicePriv *p = hwfc->device_ctx->internal->priv;
+    VulkanFramesPriv *fp = hwfc->internal->priv;
     AVVulkanDeviceContext *hwctx = hwfc->device_ctx->hwctx;
     const int planes = av_pix_fmt_count_planes(hwfc->sw_format);
     VK_LOAD_PFN(hwctx->inst, vkGetMemoryFdKHR);
@@ -2480,7 +2484,7 @@ static int vulkan_map_to_drm(AVHWFramesContext *hwfc, AVFrame *dst,
     if (!drm_desc)
         return AVERROR(ENOMEM);
 
-    err = prepare_frame(hwfc, &p->cmd, f, PREP_MODE_EXTERNAL_EXPORT);
+    err = prepare_frame(hwfc, &fp->conv_ctx, f, PREP_MODE_EXTERNAL_EXPORT);
     if (err < 0)
         goto end;