render: properly release rendered buffers

[ikalco]

Describe your PR, what does it fix/add?

as title says, this pr intends to properly do buffer release when rendering by

• ensuring we keep all surface buffers used in rendering referenced, including non-drmsyncobj buffers since wl_events.release still applies for them
• ensuring we only release buffers when rendering is done, so either on EGLSync signal or after a glFinish
• as a bonus we can also make a renderingDoneCallback, which can be useful for some purposes like screencopy

Is there anything you want to mention? (unchecked code, possible bugs, found problems, breaking compatibility, etc.)

Is it ready for merging, or does it need work?

after #9806

[ikalco]

merge after #9806 (i"ll rebase this to main then)
also some final testing from me and @gulafaran

[gulafaran]

merge after #9806 (i"ll rebase this to main then) also some testing from me and @gulafaran

As long as this pr moves from syncrelease/fd signaling to wayland eventloop/waiter releasing its going to get a no from me, as mentioned earlier it means moving from as early as possible at as correct time release possible to cpu based wait in the crowded wayland eventloop which makes it always out of time. and since this isnt per se fixing anything im not settling for a potential slower approach.

[ikalco]

merge after #9806 (i"ll rebase this to main then) also some testing from me and @gulafaran

As long as this pr moves from syncrelease/fd signaling to wayland eventloop/waiter releasing its going to get a no from me, as mentioned earlier it means moving from as early as possible at as correct time release possible to cpu based wait in the crowded wayland eventloop which makes it always out of time. and since this isnt per se fixing anything im not settling for a potential slower approach.

we're still using fd signaling, just not syncrelease

Hyprland/src/render/Renderer.cpp

Lines 2269 to 2277 in e216468

	if (eglSync.isValid()) {
	if (getExplicitSyncSettings(PMONITOR->output).explicitKMSEnabled) {
	// let kernel signal release points rather than slow wayland event loop
	for (const auto& buf : usedAsyncBuffers) {
	for (auto& point : buf->releasePoints) {
	point.importSyncFD(eglSync.fd());
	}
	}
	}

also previously we didn't release non-drmsynobj dmabuf buffers when rendering finished,
now we do through an eventfd in wayland loop
but if there's a drmsyncobj point, we signal based on EGLSync, like before, not through wayland loop

[gulafaran]

merge after #9806 (i"ll rebase this to main then) also some testing from me and @gulafaran

As long as this pr moves from syncrelease/fd signaling to wayland eventloop/waiter releasing its going to get a no from me, as mentioned earlier it means moving from as early as possible at as correct time release possible to cpu based wait in the crowded wayland eventloop which makes it always out of time. and since this isnt per se fixing anything im not settling for a potential slower approach.

we're still using fd signaling, just not syncrelease

Hyprland/src/render/Renderer.cpp

Lines 2269 to 2277 in e216468

	if (eglSync.isValid()) {
	if (getExplicitSyncSettings(PMONITOR->output).explicitKMSEnabled) {
	// let kernel signal release points rather than slow wayland event loop
	for (const auto& buf : usedAsyncBuffers) {
	for (auto& point : buf->releasePoints) {
	point.importSyncFD(eglSync.fd());
	}
	}
	}

also previously we didn't release non-drmsynobj dmabuf buffers when rendering finished, now we do through an eventfd in wayland loop but if there's a drmsyncobj point, we signal based on EGLSync, like before, not through wayland loop

well previously it accounted for both the release point fd and eglsync fd, it merged those and imported it. now it only accounts for the eglsync fd and ignores if the releasepoint fd is signaled, it was also previously signaling on destruction if the buffer wasnt rendered.

[gulafaran]

merge after #9806 (i"ll rebase this to main then) also some testing from me and @gulafaran

As long as this pr moves from syncrelease/fd signaling to wayland eventloop/waiter releasing its going to get a no from me, as mentioned earlier it means moving from as early as possible at as correct time release possible to cpu based wait in the crowded wayland eventloop which makes it always out of time. and since this isnt per se fixing anything im not settling for a potential slower approach.

we're still using fd signaling, just not syncrelease

Hyprland/src/render/Renderer.cpp

Lines 2269 to 2277 in e216468

	if (eglSync.isValid()) {
	if (getExplicitSyncSettings(PMONITOR->output).explicitKMSEnabled) {
	// let kernel signal release points rather than slow wayland event loop
	for (const auto& buf : usedAsyncBuffers) {
	for (auto& point : buf->releasePoints) {
	point.importSyncFD(eglSync.fd());
	}
	}
	}

also previously we didn't release non-drmsynobj dmabuf buffers when rendering finished, now we do through an eventfd in wayland loop but if there's a drmsyncobj point, we signal based on EGLSync, like before, not through wayland loop

well previously it accounted for both the release point fd and eglsync fd, it merged those and imported it. now it only accounts for the eglsync fd and ignores if the releasepoint fd is signaled, it was also previously signaling on destruction if the buffer wasnt rendered.

hm let me rethink that, it seems we were merely merging the eglsync fd if a new appeared before it was released. can we render the same buffer multiple times before its actually dropped? what happends if the client is at 30fps on a 60hz monitor. is the same buffer supposed to be rendered multiple times and the eglsync just merged until finally dropped?