core: wait for dmabuf readiness (#9806)

* add doOnReadable to event loop manager

* move syncTimeline addWaiter to doOnReadable

* wait on dmabuf buffers to be readable

* don't over synchronize in scanout, also give present feedback on same buffer commit

1 files changed, 5 insertions, 23 deletions

diff --git a/src/helpers/Monitor.cpp b/src/helpers/Monitor.cpp
index 495cecbc..0a16643e 100644
--- a/src/helpers/Monitor.cpp
+++ b/src/helpers/Monitor.cpp
@@ -1377,6 +1377,10 @@ bool CMonitor::attemptDirectScanout() {
     auto PBUFFER = PSURFACE->current.buffer.buffer;
 
     if (PBUFFER == output->state->state().buffer) {
+        timespec now;
+        clock_gettime(CLOCK_MONOTONIC, &now);
+        PSURFACE->presentFeedback(&now, self.lock());
+
         if (scanoutNeedsCursorUpdate) {
             if (!state.test()) {
                 Debug::log(TRACE, "attemptDirectScanout: failed basic test");
@@ -1423,32 +1427,10 @@ bool CMonitor::attemptDirectScanout() {
     output->state->addDamage(PSURFACE->current.accumulateBufferDamage());
     output->state->resetExplicitFences();
 
-    auto cleanup = CScopeGuard([this]() { output->state->resetExplicitFences(); });
-
-    auto explicitOptions = g_pHyprRenderer->getExplicitSyncSettings(output);
-
-    bool DOEXPLICIT = PSURFACE->syncobj && PSURFACE->current.buffer && PSURFACE->current.acquire && explicitOptions.explicitKMSEnabled;
-    if (DOEXPLICIT) {
-        // wait for surface's explicit fence if present
-        inFence = PSURFACE->current.acquire.exportAsFD();
-        if (inFence.isValid()) {
-            Debug::log(TRACE, "attemptDirectScanout: setting IN_FENCE for aq to {}", inFence.get());
-            output->state->setExplicitInFence(inFence.get());
-        } else {
-            Debug::log(TRACE, "attemptDirectScanout: failed to acquire an sync file fd for aq IN_FENCE");
-            DOEXPLICIT = false;
-        }
-    }
+    // no need to do explicit sync here as surface current can only ever be ready to read
 
     bool ok = output->commit();
 
-    if (!ok && DOEXPLICIT) {
-        Debug::log(TRACE, "attemptDirectScanout: EXPLICIT SYNC FAILED: commit() returned false. Resetting fences and retrying, might result in glitches.");
-        output->state->resetExplicitFences();
-
-        ok = output->commit();
-    }
-
     if (!ok) {
         Debug::log(TRACE, "attemptDirectScanout: failed to scanout surface");
         lastScanout.reset();