lavc/vaapi_av1: Avoid sending the same slice buffer multiple times

When there are multiple tiles in one slice buffer, use multiple slice
params to avoid sending the same slice buffer multiple times and thus
increasing the bitstream size the driver will need to upload to hw.

Reviewed-by: Neal Gompa <ngompa13@gmail.com>
Signed-off-by: David Rosca <nowrep@gmail.com>
Signed-off-by: Haihao Xiang <haihao.xiang@intel.com>
(cherry picked from commit d2d911eb9a)

libavcodec/vaapi_av1.c

@@ -19,6 +19,7 @@
  */
 
 #include "libavutil/frame.h"
+#include "libavutil/mem.h"
 #include "hwaccel_internal.h"
 #include "vaapi_decode.h"
 #include "internal.h"
@@ -42,6 +43,9 @@ typedef struct VAAPIAV1DecContext {
     */
     VAAPIAV1FrameRef ref_tab[AV1_NUM_REF_FRAMES];
     AVFrame *tmp_frame;
+
+    int nb_slice_params;
+    VASliceParameterBufferAV1 *slice_params;
 } VAAPIAV1DecContext;
 
 static VASurfaceID vaapi_av1_surface_id(AV1Frame *vf)
@@ -97,6 +101,8 @@ static int vaapi_av1_decode_uninit(AVCodecContext *avctx)
     for (int i = 0; i < FF_ARRAY_ELEMS(ctx->ref_tab); i++)
         av_frame_free(&ctx->ref_tab[i].frame);
 
+    av_freep(&ctx->slice_params);
+
     return ff_vaapi_decode_uninit(avctx);
 }
 
@@ -393,13 +399,24 @@ static int vaapi_av1_decode_slice(AVCodecContext *avctx,
 {
     const AV1DecContext *s = avctx->priv_data;
     VAAPIDecodePicture *pic = s->cur_frame.hwaccel_picture_private;
-    VASliceParameterBufferAV1 slice_param;
-    int err = 0;
+    VAAPIAV1DecContext *ctx = avctx->internal->hwaccel_priv_data;
+    int err, nb_params;
+
+    nb_params = s->tg_end - s->tg_start + 1;
+    if (ctx->nb_slice_params < nb_params) {
+        ctx->slice_params = av_realloc_array(ctx->slice_params,
+                                             nb_params,
+                                             sizeof(*ctx->slice_params));
+        if (!ctx->slice_params) {
+            ctx->nb_slice_params = 0;
+            err = AVERROR(ENOMEM);
+            goto fail;
+        }
+        ctx->nb_slice_params = nb_params;
+    }
 
     for (int i = s->tg_start; i <= s->tg_end; i++) {
-        memset(&slice_param, 0, sizeof(VASliceParameterBufferAV1));
-
-        slice_param = (VASliceParameterBufferAV1) {
+        ctx->slice_params[i - s->tg_start] = (VASliceParameterBufferAV1) {
             .slice_data_size   = s->tile_group_info[i].tile_size,
             .slice_data_offset = s->tile_group_info[i].tile_offset,
             .slice_data_flag   = VA_SLICE_DATA_FLAG_ALL,
@@ -408,18 +425,20 @@ static int vaapi_av1_decode_slice(AVCodecContext *avctx,
             .tg_start          = s->tg_start,
             .tg_end            = s->tg_end,
         };
-
-        err = ff_vaapi_decode_make_slice_buffer(avctx, pic, &slice_param, 1,
-                                                sizeof(VASliceParameterBufferAV1),
-                                                buffer,
-                                                size);
-        if (err) {
-            ff_vaapi_decode_cancel(avctx, pic);
-            return err;
-        }
     }
 
+    err = ff_vaapi_decode_make_slice_buffer(avctx, pic, ctx->slice_params, nb_params,
+                                            sizeof(VASliceParameterBufferAV1),
+                                            buffer,
+                                            size);
+    if (err)
+        goto fail;
+
     return 0;
+
+fail:
+    ff_vaapi_decode_cancel(avctx, pic);
+    return err;
 }
 
 const FFHWAccel ff_av1_vaapi_hwaccel = {