core: move wayland event reading into the poll thread (#655)

This was done, so that we can

  wl_display_prepare_read -> poll -> wl_display_read_events

That fixes synchronization issues on nvidia proprietary drivers.

src/core/LockSurface.cpp

@@ -117,8 +117,6 @@ void CSessionLockSurface::onScaleUpdate() {
 }
 
 void CSessionLockSurface::render() {
-    Debug::log(TRACE, "render lock");
-
     if (frameCallback || !readyForFrame) {
         needsFrame = true;
         return;
@@ -127,10 +125,16 @@ void CSessionLockSurface::render() {
     g_pAnimationManager->tick();
     const auto FEEDBACK = g_pRenderer->renderLock(*this);
     frameCallback       = makeShared<CCWlCallback>(surface->sendFrame());
-    frameCallback->setDone([this](CCWlCallback* r, uint32_t data) {
+    frameCallback->setDone([this](CCWlCallback* r, uint32_t frameTime) {
         if (g_pHyprlock->m_bTerminate)
             return;
 
+        Debug::log(TRACE, "[{}] frame {}, Current fps: {:.2f}", output->stringPort, m_frames, 1000.f / (frameTime - m_lastFrameTime));
+
+        m_lastFrameTime = frameTime;
+
+        m_frames++;
+
         onCallback();
     });
 

src/core/LockSurface.hpp

@@ -42,6 +42,9 @@ class CSessionLockSurface {
 
     bool                          needsFrame = false;
 
+    uint32_t                      m_lastFrameTime = 0;
+    uint32_t                      m_frames        = 0;
+
     // wayland callbacks
     SP<CCWlCallback> frameCallback = nullptr;
 

src/core/hyprlock.cpp

@@ -368,32 +368,45 @@ void CHyprlock::run() {
 
     std::thread pollThr([this, &pollfds, fdcount]() {
         while (!m_bTerminate) {
-            int ret = poll(pollfds, fdcount, 5000 /* 5 seconds, reasonable. Just in case we need to terminate and the signal fails */);
+            bool preparedToRead = wl_display_prepare_read(m_sWaylandState.display) == 0;
 
-            if (ret < 0) {
+            int  events = 0;
-                if (errno == EINTR)
+            if (preparedToRead) {
-                    continue;
+                events = poll(pollfds, fdcount, 5000);
 
-                Debug::log(CRIT, "[core] Polling fds failed with {}", errno);
+                if (events < 0) {
-                attemptRestoreOnDeath();
+                    if (preparedToRead)
-                m_bTerminate = true;
+                        wl_display_cancel_read(m_sWaylandState.display);
-                exit(1);
-            }
 
-            for (size_t i = 0; i < fdcount; ++i) {
+                    if (errno == EINTR)
-                if (pollfds[i].revents & POLLHUP) {
+                        continue;
-                    Debug::log(CRIT, "[core] Disconnected from pollfd id {}", i);
+
+                    Debug::log(CRIT, "[core] Polling fds failed with {}", errno);
                     attemptRestoreOnDeath();
                     m_bTerminate = true;
                     exit(1);
                 }
+
+                for (size_t i = 0; i < fdcount; ++i) {
+                    if (pollfds[i].revents & POLLHUP) {
+                        Debug::log(CRIT, "[core] Disconnected from pollfd id {}", i);
+                        attemptRestoreOnDeath();
+                        m_bTerminate = true;
+                        exit(1);
+                    }
+                }
+
+                wl_display_read_events(m_sWaylandState.display);
+                m_sLoopState.wlDispatched = false;
             }
 
-            if (ret != 0) {
+            if (events > 0 || !preparedToRead) {
                 Debug::log(TRACE, "[core] got poll event");
-                std::lock_guard<std::mutex> lg2(m_sLoopState.eventLoopMutex);
+                std::unique_lock lk(m_sLoopState.eventLoopMutex);
                 m_sLoopState.event = true;
                 m_sLoopState.loopCV.notify_all();
+
+                m_sLoopState.wlDispatchCV.wait_for(lk, std::chrono::milliseconds(100), [this] { return m_sLoopState.wlDispatched; });
             }
         }
     });
@@ -439,30 +452,18 @@ void CHyprlock::run() {
 
         m_sLoopState.event = false;
 
+        wl_display_dispatch_pending(m_sWaylandState.display);
+        wl_display_flush(m_sWaylandState.display);
+
+        m_sLoopState.wlDispatched = true;
+        m_sLoopState.wlDispatchCV.notify_all();
+
         if (pollfds[1].revents & POLLIN /* dbus */) {
             while (dbusConn && dbusConn->processPendingEvent()) {
                 ;
             }
         }
 
-        if (pollfds[0].revents & POLLIN /* wl */) {
-            Debug::log(TRACE, "got wl event");
-            wl_display_flush(m_sWaylandState.display);
-            if (wl_display_prepare_read(m_sWaylandState.display) == 0) {
-                wl_display_read_events(m_sWaylandState.display);
-                wl_display_dispatch_pending(m_sWaylandState.display);
-            } else {
-                wl_display_dispatch(m_sWaylandState.display);
-            }
-        }
-
-        // finalize wayland dispatching. Dispatch pending on the queue
-        int ret = 0;
-        do {
-            ret = wl_display_dispatch_pending(m_sWaylandState.display);
-            wl_display_flush(m_sWaylandState.display);
-        } while (ret > 0 && !m_bTerminate);
-
         // do timers
         m_sLoopState.timersMutex.lock();
         auto timerscpy = m_vTimers;

src/core/hyprlock.hpp

@@ -151,6 +151,9 @@ class CHyprlock {
         std::condition_variable loopCV;
         bool                    event = false;
 
+        std::condition_variable wlDispatchCV;
+        bool                    wlDispatched = false;
+
         std::condition_variable timerCV;
         std::mutex              timerRequestMutex;
         bool                    timerEvent = false;

src/renderer/Renderer.cpp

@@ -198,8 +198,6 @@ CRenderer::CRenderer() {
     g_pAnimationManager->createAnimation(0.f, opacity, g_pConfigManager->m_AnimationTree.getConfig("fadeIn"));
 }
 
-static int frames = 0;
-
 //
 CRenderer::SRenderFeedback CRenderer::renderLock(const CSessionLockSurface& surf) {
     static auto* const PDISABLEBAR = (Hyprlang::INT* const*)g_pConfigManager->getValuePtr("general:disable_loading_bar");
@@ -238,10 +236,6 @@ CRenderer::SRenderFeedback CRenderer::renderLock(const CSessionLockSurface& surf
         }
     }
 
-    frames++;
-
-    Debug::log(TRACE, "frame {}", frames);
-
     feedback.needsFrame = feedback.needsFrame || !asyncResourceGatherer->gathered;
 
     glDisable(GL_BLEND);