omxvideodec: fixes race condition during seeks

Acording 6.1.3 Seek Event Sequence in the OpenMAX IL 1.1.2 spec
document in order to flush the component it needs to be in
paused state.

https://bugzilla.gnome.org/show_bug.cgi?id=726038

1 files changed, 46 insertions, 15 deletions

diff --git a/omx/gstomxvideodec.c b/omx/gstomxvideodec.c
index 8a46d40..682ac8f 100644
--- a/omx/gstomxvideodec.c
+++ b/omx/gstomxvideodec.c
@@ -1950,6 +1950,30 @@ gst_omx_video_dec_flush (GstVideoDecoder * decoder)
   if (gst_omx_component_get_state (self->dec, 0) == OMX_StateLoaded)
     return TRUE;
 
+  /* 0) Wait until the srcpad loop is stopped,
+   * unlock GST_VIDEO_DECODER_STREAM_LOCK to prevent deadlocks
+   * caused by using this lock from inside the loop function */
+  GST_VIDEO_DECODER_STREAM_UNLOCK (self);
+  gst_pad_stop_task (GST_VIDEO_DECODER_SRC_PAD (decoder));
+  GST_DEBUG_OBJECT (self, "Flushing -- task stopped");
+  GST_VIDEO_DECODER_STREAM_LOCK (self);
+
+  /* 1) Pause the components */
+  if (gst_omx_component_get_state (self->dec, 0) == OMX_StateExecuting) {
+    gst_omx_component_set_state (self->dec, OMX_StatePause);
+    gst_omx_component_get_state (self->dec, GST_CLOCK_TIME_NONE);
+  }
+#if defined (USE_OMX_TARGET_RPI) && defined (HAVE_GST_EGL)
+  if (self->eglimage) {
+    if (gst_omx_component_get_state (self->egl_render, 0) == OMX_StateExecuting) {
+      gst_omx_component_set_state (self->egl_render, OMX_StatePause);
+      gst_omx_component_get_state (self->egl_render, GST_CLOCK_TIME_NONE);
+    }
+  }
+#endif
+
+  /* 2) Flush the ports */
+  GST_DEBUG_OBJECT (self, "flushing ports");
   gst_omx_port_set_flushing (self->dec_in_port, 5 * GST_SECOND, TRUE);
   gst_omx_port_set_flushing (self->dec_out_port, 5 * GST_SECOND, TRUE);
 
@@ -1960,14 +1984,17 @@ gst_omx_video_dec_flush (GstVideoDecoder * decoder)
   }
 #endif
 
-  /* Wait until the srcpad loop is finished,
-   * unlock GST_VIDEO_DECODER_STREAM_LOCK to prevent deadlocks
-   * caused by using this lock from inside the loop function */
-  GST_VIDEO_DECODER_STREAM_UNLOCK (self);
-  GST_PAD_STREAM_LOCK (GST_VIDEO_DECODER_SRC_PAD (self));
-  GST_PAD_STREAM_UNLOCK (GST_VIDEO_DECODER_SRC_PAD (self));
-  GST_VIDEO_DECODER_STREAM_LOCK (self);
+  /* 3) Resume components */
+  gst_omx_component_set_state (self->dec, OMX_StateExecuting);
+  gst_omx_component_get_state (self->dec, GST_CLOCK_TIME_NONE);
+#if defined (USE_OMX_TARGET_RPI) && defined (HAVE_GST_EGL)
+  if (self->eglimage) {
+    gst_omx_component_set_state (self->egl_render, OMX_StateExecuting);
+    gst_omx_component_get_state (self->egl_render, GST_CLOCK_TIME_NONE);
+  }
+#endif
 
+  /* 4) Unset flushing to allow ports to accept data again */
   gst_omx_port_set_flushing (self->dec_in_port, 5 * GST_SECOND, FALSE);
   gst_omx_port_set_flushing (self->dec_out_port, 5 * GST_SECOND, FALSE);
 
@@ -1976,6 +2003,7 @@ gst_omx_video_dec_flush (GstVideoDecoder * decoder)
     gst_omx_port_set_flushing (self->egl_in_port, 5 * GST_SECOND, FALSE);
     gst_omx_port_set_flushing (self->egl_out_port, 5 * GST_SECOND, FALSE);
     err = gst_omx_port_populate (self->egl_out_port);
+    gst_omx_port_mark_reconfigured (self->egl_out_port);
   } else {
     err = gst_omx_port_populate (self->dec_out_port);
   }
@@ -1988,14 +2016,12 @@ gst_omx_video_dec_flush (GstVideoDecoder * decoder)
         gst_omx_error_to_string (err), err);
   }
 
-  /* Start the srcpad loop again */
+  /* Reset our state */
   self->last_upstream_ts = 0;
   self->eos = FALSE;
   self->downstream_flow_ret = GST_FLOW_OK;
-  gst_pad_start_task (GST_VIDEO_DECODER_SRC_PAD (self),
-      (GstTaskFunction) gst_omx_video_dec_loop, decoder, NULL);
-
-  GST_DEBUG_OBJECT (self, "Flush decoder");
+  self->started = FALSE;
+  GST_DEBUG_OBJECT (self, "Flush finished");
 
   return TRUE;
 }
@@ -2025,9 +2051,14 @@ gst_omx_video_dec_handle_frame (GstVideoDecoder * decoder,
     return GST_FLOW_EOS;
   }
 
-  if (!self->started && !GST_VIDEO_CODEC_FRAME_IS_SYNC_POINT (frame)) {
-    gst_video_decoder_drop_frame (GST_VIDEO_DECODER (self), frame);
-    return GST_FLOW_OK;
+  if (!self->started) {
+    if (!GST_VIDEO_CODEC_FRAME_IS_SYNC_POINT (frame)) {
+      gst_video_decoder_drop_frame (GST_VIDEO_DECODER (self), frame);
+      return GST_FLOW_OK;
+    }
+    GST_DEBUG_OBJECT (self, "Starting task");
+    gst_pad_start_task (GST_VIDEO_DECODER_SRC_PAD (self),
+        (GstTaskFunction) gst_omx_video_dec_loop, decoder, NULL);
   }
 
   timestamp = frame->pts;