[PATCH 1/2] wayland: Add support for eglSwapInterval
Neil Roberts
neil at linux.intel.com
Wed Sep 11 11:28:31 PDT 2013
The Wayland EGL platform now respects the eglSwapInterval value. The value is
clamped to either 0 or 1 because it is difficult (and probably not useful) to
sync to more than 1 redraw.
The main change is that if the swap interval is 0 then it simply doesn't
install a frame callback so that the next time eglSwapBuffers is called it
won't delay.
The second change is that in get_back_bo instead of returning with an error if
all three buffers are locked it will now block in a dispatch loop so that it
can receive the buffer release events. The assumption is that the compositor
is unlikely to lock all three buffers so if we find that all the buffers are
locked then we are probably just rendering faster than we are processing the
release events. Therefore the release events should be available very early.
This also moves the vblank configuration defines from platform_x11.c to the
common egl_dri2.h header so they can be shared by both platforms.
---
src/egl/drivers/dri2/egl_dri2.h | 6 ++
src/egl/drivers/dri2/platform_wayland.c | 121 ++++++++++++++++++++++++++------
src/egl/drivers/dri2/platform_x11.c | 6 --
3 files changed, 107 insertions(+), 26 deletions(-)
diff --git a/src/egl/drivers/dri2/egl_dri2.h b/src/egl/drivers/dri2/egl_dri2.h
index fba5f81..849927b 100644
--- a/src/egl/drivers/dri2/egl_dri2.h
+++ b/src/egl/drivers/dri2/egl_dri2.h
@@ -221,6 +221,12 @@ struct dri2_egl_image
__DRIimage *dri_image;
};
+/* From xmlpool/options.h, user exposed so should be stable */
+#define DRI_CONF_VBLANK_NEVER 0
+#define DRI_CONF_VBLANK_DEF_INTERVAL_0 1
+#define DRI_CONF_VBLANK_DEF_INTERVAL_1 2
+#define DRI_CONF_VBLANK_ALWAYS_SYNC 3
+
/* standard typecasts */
_EGL_DRIVER_STANDARD_TYPECASTS(dri2_egl)
_EGL_DRIVER_TYPECAST(dri2_egl_image, _EGLImage, obj)
diff --git a/src/egl/drivers/dri2/platform_wayland.c b/src/egl/drivers/dri2/platform_wayland.c
index ffc5959..83e7aab 100644
--- a/src/egl/drivers/dri2/platform_wayland.c
+++ b/src/egl/drivers/dri2/platform_wayland.c
@@ -180,8 +180,16 @@ dri2_create_window_surface(_EGLDriver *drv, _EGLDisplay *disp,
_EGLConfig *conf, EGLNativeWindowType window,
const EGLint *attrib_list)
{
- return dri2_create_surface(drv, disp, EGL_WINDOW_BIT, conf,
+ struct dri2_egl_display *dri2_dpy = dri2_egl_display(disp);
+ _EGLSurface *surf;
+
+ surf = dri2_create_surface(drv, disp, EGL_WINDOW_BIT, conf,
window, attrib_list);
+
+ if (surf != NULL)
+ drv->API.SwapInterval(drv, disp, surf, dri2_dpy->default_swap_interval);
+
+ return surf;
}
/**
@@ -261,24 +269,36 @@ get_back_bo(struct dri2_egl_surface *dri2_surf, __DRIbuffer *buffer)
__DRIimage *image;
int i, name, pitch;
- /* There might be a buffer release already queued that wasn't processed */
- wl_display_dispatch_queue_pending(dri2_dpy->wl_dpy, dri2_dpy->wl_queue);
-
if (dri2_surf->back == NULL) {
- for (i = 0; i < ARRAY_SIZE(dri2_surf->color_buffers); i++) {
- /* Get an unlocked buffer, preferrably one with a dri_buffer already
- * allocated. */
- if (dri2_surf->color_buffers[i].locked)
- continue;
- if (dri2_surf->back == NULL)
- dri2_surf->back = &dri2_surf->color_buffers[i];
- else if (dri2_surf->back->dri_image == NULL)
- dri2_surf->back = &dri2_surf->color_buffers[i];
+ /* There might be a buffer release already queued that wasn't processed */
+ wl_display_dispatch_queue_pending(dri2_dpy->wl_dpy, dri2_dpy->wl_queue);
+
+ while (1) {
+ for (i = 0; i < ARRAY_SIZE(dri2_surf->color_buffers); i++) {
+ /* Get an unlocked buffer, preferrably one with a dri_buffer already
+ * allocated. */
+ if (dri2_surf->color_buffers[i].locked)
+ continue;
+ if (dri2_surf->back == NULL)
+ dri2_surf->back = &dri2_surf->color_buffers[i];
+ else if (dri2_surf->back->dri_image == NULL)
+ dri2_surf->back = &dri2_surf->color_buffers[i];
+ }
+
+ if (dri2_surf->back)
+ break;
+
+ /* If we make it here then here then all of the buffers are locked.
+ * It wouldn't make sense for the compositor to keep all three
+ * buffers so it must mean that we are rendering too fast without
+ * getting a chance to see the release events. Therefore we can just
+ * block for the release event here */
+ if (wl_display_dispatch_queue(dri2_dpy->wl_dpy,
+ dri2_dpy->wl_queue) < 0)
+ return -1;
}
}
- if (dri2_surf->back == NULL)
- return -1;
if (dri2_surf->back->dri_image == NULL) {
dri2_surf->back->dri_image =
dri2_dpy->image->createImage(dri2_dpy->dri_screen,
@@ -511,11 +531,13 @@ dri2_swap_buffers_with_damage(_EGLDriver *drv,
if (ret < 0)
return EGL_FALSE;
- dri2_surf->frame_callback = wl_surface_frame(dri2_surf->wl_win->surface);
- wl_callback_add_listener(dri2_surf->frame_callback,
- &frame_listener, dri2_surf);
- wl_proxy_set_queue((struct wl_proxy *) dri2_surf->frame_callback,
- dri2_dpy->wl_queue);
+ if (draw->SwapInterval > 0) {
+ dri2_surf->frame_callback = wl_surface_frame(dri2_surf->wl_win->surface);
+ wl_callback_add_listener(dri2_surf->frame_callback,
+ &frame_listener, dri2_surf);
+ wl_proxy_set_queue((struct wl_proxy *) dri2_surf->frame_callback,
+ dri2_dpy->wl_queue);
+ }
for (i = 0; i < ARRAY_SIZE(dri2_surf->color_buffers); i++)
if (dri2_surf->color_buffers[i].age > 0)
@@ -802,6 +824,60 @@ static const struct wl_registry_listener registry_listener = {
registry_handle_global_remove
};
+static EGLBoolean
+dri2_swap_interval(_EGLDriver *drv,
+ _EGLDisplay *disp,
+ _EGLSurface *surf,
+ EGLint interval)
+{
+ if (interval > surf->Config->MaxSwapInterval)
+ interval = surf->Config->MaxSwapInterval;
+ else if (interval < surf->Config->MinSwapInterval)
+ interval = surf->Config->MinSwapInterval;
+
+ surf->SwapInterval = interval;
+
+ return EGL_TRUE;
+}
+
+static void
+dri2_setup_swap_interval(struct dri2_egl_display *dri2_dpy)
+{
+ GLint vblank_mode = DRI_CONF_VBLANK_DEF_INTERVAL_1;
+
+ /* We can't use values greater than 1 on Wayland because we are using the
+ * frame callback to synchronise the frame and the only way we be sure to
+ * get a frame callback is to attach a new buffer. Therefore we can't just
+ * sit drawing nothing to wait until the next ‘n’ frame callbacks */
+
+ if (dri2_dpy->config)
+ dri2_dpy->config->configQueryi(dri2_dpy->dri_screen,
+ "vblank_mode", &vblank_mode);
+ switch (vblank_mode) {
+ case DRI_CONF_VBLANK_NEVER:
+ dri2_dpy->min_swap_interval = 0;
+ dri2_dpy->max_swap_interval = 0;
+ dri2_dpy->default_swap_interval = 0;
+ break;
+ case DRI_CONF_VBLANK_ALWAYS_SYNC:
+ dri2_dpy->min_swap_interval = 1;
+ dri2_dpy->max_swap_interval = 1;
+ dri2_dpy->default_swap_interval = 1;
+ break;
+ case DRI_CONF_VBLANK_DEF_INTERVAL_0:
+ dri2_dpy->min_swap_interval = 0;
+ dri2_dpy->max_swap_interval = 1;
+ dri2_dpy->default_swap_interval = 0;
+ break;
+ default:
+ case DRI_CONF_VBLANK_DEF_INTERVAL_1:
+ dri2_dpy->min_swap_interval = 0;
+ dri2_dpy->max_swap_interval = 1;
+ dri2_dpy->default_swap_interval = 1;
+ break;
+ }
+}
+
EGLBoolean
dri2_initialize_wayland(_EGLDriver *drv, _EGLDisplay *disp)
{
@@ -817,6 +893,7 @@ dri2_initialize_wayland(_EGLDriver *drv, _EGLDisplay *disp)
drv->API.DestroySurface = dri2_destroy_surface;
drv->API.SwapBuffers = dri2_swap_buffers;
drv->API.SwapBuffersWithDamageEXT = dri2_swap_buffers_with_damage;
+ drv->API.SwapInterval = dri2_swap_interval;
drv->API.Terminate = dri2_terminate;
drv->API.QueryBufferAge = dri2_query_buffer_age;
drv->API.CreateWaylandBufferFromImageWL =
@@ -876,9 +953,13 @@ dri2_initialize_wayland(_EGLDriver *drv, _EGLDisplay *disp)
dri2_dpy->extensions[2] = &use_invalidate.base;
dri2_dpy->extensions[3] = NULL;
+ dri2_dpy->swap_available = EGL_TRUE;
+
if (!dri2_create_screen(disp))
goto cleanup_driver;
+ dri2_setup_swap_interval(dri2_dpy);
+
/* The server shouldn't advertise WL_DRM_CAPABILITY_PRIME if the driver
* doesn't have createImageFromFds, since we're using the same driver on
* both sides. We don't want crash if that happens anyway, so fall back to
diff --git a/src/egl/drivers/dri2/platform_x11.c b/src/egl/drivers/dri2/platform_x11.c
index ec76aec..f2cd4fc 100644
--- a/src/egl/drivers/dri2/platform_x11.c
+++ b/src/egl/drivers/dri2/platform_x11.c
@@ -39,12 +39,6 @@
#include "egl_dri2.h"
-/* From xmlpool/options.h, user exposed so should be stable */
-#define DRI_CONF_VBLANK_NEVER 0
-#define DRI_CONF_VBLANK_DEF_INTERVAL_0 1
-#define DRI_CONF_VBLANK_DEF_INTERVAL_1 2
-#define DRI_CONF_VBLANK_ALWAYS_SYNC 3
-
static void
swrastCreateDrawable(struct dri2_egl_display * dri2_dpy,
struct dri2_egl_surface * dri2_surf,
--
1.8.3.1
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