backend-drm: make sure all buffers are released when an output is removed

When an output is destroyed then the output state is freed immediately. In this
case, the plane state is only partially destroyed because it is the currently
active state. This includes the buffer reference.

Without the output, the plane will not be updated any more until it is used by a
different output (if possible) or the output returns and the plane is used
again.
As a result, the buffer reference is kept for a long time. This will cause some
applications to stall because weston now keeps two buffers (the one here and
another one for a different output where the application is now displayed).

To avoid this, do a synchronous commit that disables the output. The output
needs to be disabled anyways and this way the current state contains no
buffers that would remain.

`device->state_invalid = true` in drm_output_detach_crtc() is no longer
needed, because drm_output_detach_crtc() is called only when initialization
failed and the crtc was not yet used or in drm_output_deinit() when the
crtc was already disabled with the new synchronous commit.

Signed-off-by: Michael Olbrich <m.olbrich@pengutronix.de>
This commit is contained in:
Michael Olbrich 2022-06-22 08:58:21 +02:00 committed by Daniel Stone
parent 158c3ef0dd
commit f5a4fb5abc

View File

@ -1811,14 +1811,10 @@ drm_output_attach_crtc(struct drm_output *output)
static void
drm_output_detach_crtc(struct drm_output *output)
{
struct drm_device *device = output->device;
struct drm_crtc *crtc = output->crtc;
crtc->output = NULL;
output->crtc = NULL;
/* Force resetting unused CRTCs */
device->state_invalid = true;
}
static int
@ -1891,6 +1887,13 @@ drm_output_deinit(struct weston_output *base)
struct drm_output *output = to_drm_output(base);
struct drm_backend *b = to_drm_backend(base->compositor);
struct drm_device *device = b->drm;
struct drm_pending_state *pending;
if (!b->shutting_down) {
pending = drm_pending_state_alloc(device);
drm_output_get_disable_state(pending, output);
drm_pending_state_apply_sync(pending);
}
if (b->use_pixman)
drm_output_fini_pixman(output);