From a486d1af667e93e299b35b83625d49ee12575a90 Mon Sep 17 00:00:00 2001
From: Gwenole Beauchesne <gwenole.beauchesne@intel.com>
Date: Mon, 7 Jan 2013 13:59:07 +0100
Subject: [PATCH] decoder: optimize pre-allocation of decoder units.

Optimize pre-allocation of decoder units, thus avoiding un-necessary
memory reallocations. The heuristic used is that we could have around
one slice unit per macroblock line.
---
 gst-libs/gst/vaapi/gstvaapidecoder.c       |  7 +++++--
 gst-libs/gst/vaapi/gstvaapidecoder_frame.c | 13 ++++++++++---
 gst-libs/gst/vaapi/gstvaapidecoder_frame.h |  2 +-
 3 files changed, 16 insertions(+), 6 deletions(-)

diff --git a/gst-libs/gst/vaapi/gstvaapidecoder.c b/gst-libs/gst/vaapi/gstvaapidecoder.c
index 7a5cf0501b..966d3ea784 100644
--- a/gst-libs/gst/vaapi/gstvaapidecoder.c
+++ b/gst-libs/gst/vaapi/gstvaapidecoder.c
@@ -135,7 +135,8 @@ do_parse(GstVaapiDecoder *decoder,
     GstVideoCodecFrame *base_frame, GstAdapter *adapter, gboolean at_eos,
     guint *got_unit_size_ptr, gboolean *got_frame_ptr)
 {
-    GstVaapiParserState * const ps = &decoder->priv->parser_state;
+    GstVaapiDecoderPrivate * const priv = decoder->priv;
+    GstVaapiParserState * const ps = &priv->parser_state;
     GstVaapiDecoderFrame *frame;
     GstVaapiDecoderUnit *unit;
     GstVaapiDecoderStatus status;
@@ -145,7 +146,9 @@ do_parse(GstVaapiDecoder *decoder,
 
     frame = gst_video_codec_frame_get_user_data(base_frame);
     if (!frame) {
-        frame = gst_vaapi_decoder_frame_new();
+        GstVideoCodecState * const codec_state = priv->codec_state;
+        frame = gst_vaapi_decoder_frame_new(codec_state->info.width,
+            codec_state->info.height);
         if (!frame)
             return GST_VAAPI_DECODER_STATUS_ERROR_ALLOCATION_FAILED;
         gst_video_codec_frame_set_user_data(base_frame,
diff --git a/gst-libs/gst/vaapi/gstvaapidecoder_frame.c b/gst-libs/gst/vaapi/gstvaapidecoder_frame.c
index 4c1c178cee..cae0d30873 100644
--- a/gst-libs/gst/vaapi/gstvaapidecoder_frame.c
+++ b/gst-libs/gst/vaapi/gstvaapidecoder_frame.c
@@ -66,24 +66,31 @@ free_units(GArray **units_ptr)
 
 /**
  * gst_vaapi_decoder_frame_new:
+ * @width: frame width in pixels
+ * @height: frame height in pixels
  *
  * Creates a new #GstVaapiDecoderFrame object.
  *
  * Returns: The newly allocated #GstVaapiDecoderFrame
  */
 GstVaapiDecoderFrame *
-gst_vaapi_decoder_frame_new(void)
+gst_vaapi_decoder_frame_new(guint width, guint height)
 {
     GstVaapiDecoderFrame *frame;
+    guint num_slices;
 
     frame = (GstVaapiDecoderFrame *)
         gst_vaapi_mini_object_new(gst_vaapi_decoder_frame_class());
     if (!frame)
         return NULL;
 
-    if (!alloc_units(&frame->pre_units, 4))
+    if (!height)
+        height = 1088;
+    num_slices = (height + 15) / 16;
+
+    if (!alloc_units(&frame->pre_units, 16))
         goto error;
-    if (!alloc_units(&frame->units, 1))
+    if (!alloc_units(&frame->units, num_slices))
         goto error;
     if (!alloc_units(&frame->post_units, 1))
         goto error;
diff --git a/gst-libs/gst/vaapi/gstvaapidecoder_frame.h b/gst-libs/gst/vaapi/gstvaapidecoder_frame.h
index b89bb5dae9..4a3595a368 100644
--- a/gst-libs/gst/vaapi/gstvaapidecoder_frame.h
+++ b/gst-libs/gst/vaapi/gstvaapidecoder_frame.h
@@ -76,7 +76,7 @@ struct _GstVaapiDecoderFrame {
 
 G_GNUC_INTERNAL
 GstVaapiDecoderFrame *
-gst_vaapi_decoder_frame_new(void);
+gst_vaapi_decoder_frame_new(guint width, guint height);
 
 G_GNUC_INTERNAL
 void