From 0ef79219ab24104867ba5406a066cbd0c8869184 Mon Sep 17 00:00:00 2001 From: "Randy Li (ayaka)" Date: Tue, 15 Dec 2020 18:11:08 +0800 Subject: [PATCH 03/42] waylandsink: prevent frame callback being released twice For those using context from the application which would be the embedded video case, if the frame callback is entering at the same time as window is finalizing, a wayland proxy object would be destroyed twice, leading the refcout less than zero in the second time, it can throw an abort() in wayland. For those top window case, which as a directly connection to the compositor, they can stop the message queue then the frame callback won't happen at the same time as the window is finalizing. It doesn't think it would bother them about this. Part-of: (cherry picked from commit 0d746d1022c7f83bc297584cb4d456cae4697cbf) Signed-off-by: Jeffy Chen --- ext/wayland/gstwaylandsink.c | 25 ++++++++++++++++--------- ext/wayland/gstwaylandsink.h | 2 ++ ext/wayland/wlwindow.c | 4 ---- ext/wayland/wlwindow.h | 1 - 4 files changed, 18 insertions(+), 14 deletions(-) diff --git a/ext/wayland/gstwaylandsink.c b/ext/wayland/gstwaylandsink.c index 47192df46..1c74147cf 100644 --- a/ext/wayland/gstwaylandsink.c +++ b/ext/wayland/gstwaylandsink.c @@ -404,6 +404,14 @@ gst_wayland_sink_change_state (GstElement * element, GstStateChange transition) gst_wl_window_render (sink->window, NULL, NULL); } } + + g_mutex_lock (&sink->render_lock); + if (sink->callback) { + wl_callback_destroy (sink->callback); + sink->callback = NULL; + } + sink->redraw_pending = FALSE; + g_mutex_unlock (&sink->render_lock); break; case GST_STATE_CHANGE_READY_TO_NULL: g_mutex_lock (&sink->display_lock); @@ -417,12 +425,9 @@ gst_wayland_sink_change_state (GstElement * element, GstStateChange transition) * to avoid requesting them again from the application if/when we are * restarted (GstVideoOverlay behaves like that in other sinks) */ - if (sink->display && !sink->window) { /* -> the window was toplevel */ + if (sink->display && !sink->window) /* -> the window was toplevel */ g_clear_object (&sink->display); - g_mutex_lock (&sink->render_lock); - sink->redraw_pending = FALSE; - g_mutex_unlock (&sink->render_lock); - } + g_mutex_unlock (&sink->display_lock); g_clear_object (&sink->pool); break; @@ -637,10 +642,12 @@ frame_redraw_callback (void *data, struct wl_callback *callback, uint32_t time) g_mutex_lock (&sink->render_lock); sink->redraw_pending = FALSE; - sink->window->callback = NULL; - g_mutex_unlock (&sink->render_lock); - wl_callback_destroy (callback); + if (sink->callback) { + wl_callback_destroy (callback); + sink->callback = NULL; + } + g_mutex_unlock (&sink->render_lock); } static const struct wl_callback_listener frame_callback_listener = { @@ -661,7 +668,7 @@ render_last_buffer (GstWaylandSink * sink, gboolean redraw) sink->redraw_pending = TRUE; callback = wl_surface_frame (surface); - sink->window->callback = callback; + sink->callback = callback; wl_callback_add_listener (callback, &frame_callback_listener, sink); if (G_UNLIKELY (sink->video_info_changed && !redraw)) { diff --git a/ext/wayland/gstwaylandsink.h b/ext/wayland/gstwaylandsink.h index be92fe7f2..23a4ebd65 100644 --- a/ext/wayland/gstwaylandsink.h +++ b/ext/wayland/gstwaylandsink.h @@ -67,6 +67,8 @@ struct _GstWaylandSink gboolean redraw_pending; GMutex render_lock; GstBuffer *last_buffer; + + struct wl_callback *callback; }; struct _GstWaylandSinkClass diff --git a/ext/wayland/wlwindow.c b/ext/wayland/wlwindow.c index 2a09b93ea..66a05be97 100644 --- a/ext/wayland/wlwindow.c +++ b/ext/wayland/wlwindow.c @@ -157,9 +157,6 @@ gst_wl_window_finalize (GObject * gobject) { GstWlWindow *self = GST_WL_WINDOW (gobject); - if (self->callback) - wl_callback_destroy (self->callback); - if (self->wl_shell_surface) wl_shell_surface_destroy (self->wl_shell_surface); @@ -200,7 +197,6 @@ gst_wl_window_new_internal (GstWlDisplay * display, GMutex * render_lock) window->render_lock = render_lock; g_cond_init (&window->configure_cond); - window->callback = NULL; window->area_surface = wl_compositor_create_surface (display->compositor); window->video_surface = wl_compositor_create_surface (display->compositor); diff --git a/ext/wayland/wlwindow.h b/ext/wayland/wlwindow.h index cecbda664..c3f017216 100644 --- a/ext/wayland/wlwindow.h +++ b/ext/wayland/wlwindow.h @@ -55,7 +55,6 @@ struct _GstWlWindow struct wl_shell_surface *wl_shell_surface; struct xdg_surface *xdg_surface; struct xdg_toplevel *xdg_toplevel; - struct wl_callback *callback; gboolean configured; GCond configure_cond; GMutex configure_mutex; -- 2.20.1