[FFmpeg-devel] [PATCH 1/2] hwcontext_vulkan: add a new mechanism to expose used queue families

[Lynne]

The issue with the old mechanism is that we had to introduce new
API each time we needed a new queue family, and all the queue families
were functionally fixed to a given purpose.

Nvidia's GPUs are able to handle video encoding and compute on the
same queue, which results in a speedup when pre-processing is required.

Also, this enables us to expose optical flow queues for frame interpolation.
---
APIChanges and lavu version will be bumped when comitting.

 libavutil/hwcontext_vulkan.c | 22 ++++++++++++++++++++++
 libavutil/hwcontext_vulkan.h | 22 ++++++++++++++++++++++
 2 files changed, 44 insertions(+)

diff --git a/libavutil/hwcontext_vulkan.c b/libavutil/hwcontext_vulkan.c
index da377aa1a4..ff5d34d042 100644
--- a/libavutil/hwcontext_vulkan.c
+++ b/libavutil/hwcontext_vulkan.c
@@ -1550,6 +1550,28 @@ static int vulkan_device_init(AVHWDeviceContext *ctx)
 
 #undef CHECK_QUEUE
 
+    /* Update the new queue family fields. If non-zero already,
+     * it means API users have set it. */
+    if (!hwctx->nb_qf) {
+#define ADD_QUEUE(ctx_qf, qc, flag)                                    \
+    do {                                                               \
+        if (ctx_qf != -1) {                                            \
+            hwctx->qf[hwctx->nb_qf++] = (AVVulkanDeviceQueueFamily) {  \
+                .idx = ctx_qf,                                         \
+                .num = qc,                                             \
+                .flags = flag,                                         \
+            };                                                         \
+        }                                                              \
+    } while (0)
+
+        ADD_QUEUE(hwctx->queue_family_index, hwctx->nb_graphics_queues, VK_QUEUE_GRAPHICS_BIT);
+        ADD_QUEUE(hwctx->queue_family_comp_index, hwctx->nb_comp_queues, VK_QUEUE_COMPUTE_BIT);
+        ADD_QUEUE(hwctx->queue_family_tx_index, hwctx->nb_tx_queues, VK_QUEUE_TRANSFER_BIT);
+        ADD_QUEUE(hwctx->queue_family_decode_index, hwctx->nb_decode_queues, VK_QUEUE_VIDEO_DECODE_BIT_KHR);
+        ADD_QUEUE(hwctx->queue_family_encode_index, hwctx->nb_encode_queues, VK_QUEUE_VIDEO_ENCODE_BIT_KHR);
+#undef ADD_QUEUE
+    }
+
     if (!hwctx->lock_queue)
         hwctx->lock_queue = lock_queue;
     if (!hwctx->unlock_queue)
diff --git a/libavutil/hwcontext_vulkan.h b/libavutil/hwcontext_vulkan.h
index cbbd2390c1..28fc2c73ff 100644
--- a/libavutil/hwcontext_vulkan.h
+++ b/libavutil/hwcontext_vulkan.h
@@ -30,6 +30,17 @@
 
 typedef struct AVVkFrame AVVkFrame;
 
+typedef struct AVVulkanDeviceQueueFamily {
+    /* Queue family index */
+    int idx;
+    /* Number of queues in the queue family in use */
+    int num;
+    /* Queue family capabilities. Must be non-zero.
+     * Flags may be removed to indicate the queue family may not be used
+     * for a given purpose. */
+    VkQueueFlagBits flags;
+} AVVulkanDeviceQueueFamily;
+
 /**
  * @file
  * API-specific header for AV_HWDEVICE_TYPE_VULKAN.
@@ -151,6 +162,17 @@ typedef struct AVVulkanDeviceContext {
      * Similar to lock_queue(), unlocks a queue. Must only be called after locking.
      */
     void (*unlock_queue)(struct AVHWDeviceContext *ctx, uint32_t queue_family, uint32_t index);
+
+    /**
+     * Queue families used. Must be preferentially ordered. List may contain
+     * duplicates, as long as their capability flags do not match.
+     *
+     * For compatibility reasons, all the enabled queue families listed above
+     * (queue_family_(tx/comp/encode/decode)_index) must also be included in
+     * this list until they're removed after deprecation.
+     */
+    AVVulkanDeviceQueueFamily qf[16];
+    int nb_qf;
 } AVVulkanDeviceContext;
 
 /**
-- 
2.45.1.288.g0e0cd299f1