From 9bb1d13afa5ca62b1c6cbf7fb617a30b10f28e89 Mon Sep 17 00:00:00 2001
From: Bartosz Taudul <wolf.pld@gmail.com>
Date: Sun, 7 Feb 2021 18:11:24 +0100
Subject: [PATCH] Revert to non-shared mutex for data lock.

The main change here is that the UI will be unresponsive when a trace is being
saved when there's no capture being performed. Note that the UI was always
frozen during saving if the capture was live, due to how starvation is
prevented by the locks.
---
 server/TracyView.cpp   |  8 ++++----
 server/TracyWorker.cpp | 16 ++++++++--------
 server/TracyWorker.hpp |  4 ++--
 3 files changed, 14 insertions(+), 14 deletions(-)

diff --git a/server/TracyView.cpp b/server/TracyView.cpp
index 36dd9e0d..d9e0875d 100644
--- a/server/TracyView.cpp
+++ b/server/TracyView.cpp
@@ -730,7 +730,7 @@ bool View::DrawImpl()
             ImGui::EndPopup();
         }
     }
-    std::shared_lock<std::shared_mutex> lock( m_worker.GetDataLock() );
+    std::lock_guard<std::mutex> lock( m_worker.GetDataLock() );
     if( !m_worker.IsDataStatic() )
     {
         if( m_worker.IsConnected() )
@@ -1407,7 +1407,7 @@ bool View::DrawConnection()
     ImGui::GetWindowDrawList()->AddCircleFilled( wpos + ImVec2( 1 + cs * 0.5, 3 + ty * 1.75 ), cs * 0.5, isConnected ? 0xFF2222CC : 0xFF444444, 10 );
 
     {
-        std::shared_lock<std::shared_mutex> lock( m_worker.GetDataLock() );
+        std::lock_guard<std::mutex> lock( m_worker.GetDataLock() );
         ImGui::SameLine();
         TextFocused( "+", RealToString( m_worker.GetSendInFlight() ) );
         const auto sz = m_worker.GetFrameCount( *m_frames );
@@ -1475,7 +1475,7 @@ bool View::DrawConnection()
                 m_userData.StateShouldBePreserved();
                 m_saveThreadState.store( SaveThreadState::Saving, std::memory_order_relaxed );
                 m_saveThread = std::thread( [this, f{std::move( f )}] {
-                    std::shared_lock<std::shared_mutex> lock( m_worker.GetDataLock() );
+                    std::lock_guard<std::mutex> lock( m_worker.GetDataLock() );
                     m_worker.Write( *f );
                     f->Finish();
                     const auto stats = f->GetCompressionStatistics();
@@ -1489,7 +1489,7 @@ bool View::DrawConnection()
 
     ImGui::SameLine( 0, 2 * ty );
     const char* stopStr = ICON_FA_PLUG " Stop";
-    std::shared_lock<std::shared_mutex> lock( m_worker.GetDataLock() );
+    std::lock_guard<std::mutex> lock( m_worker.GetDataLock() );
     if( !m_disconnectIssued && m_worker.IsConnected() )
     {
         if( ImGui::Button( stopStr ) )
diff --git a/server/TracyWorker.cpp b/server/TracyWorker.cpp
index 0c1e876b..102e029b 100644
--- a/server/TracyWorker.cpp
+++ b/server/TracyWorker.cpp
@@ -1785,7 +1785,7 @@ Worker::Worker( FileRead& f, EventType::Type eventMask, bool bgTasks )
                         }
                         for( auto& v : counts ) UpdateSampleStatistics( v.first, v.second, false );
                     }
-                    std::lock_guard<std::shared_mutex> lock( m_data.lock );
+                    std::lock_guard<std::mutex> lock( m_data.lock );
                     m_data.callstackSamplesReady = true;
                 } ) );
 
@@ -1801,7 +1801,7 @@ Worker::Worker( FileRead& f, EventType::Type eventMask, bool bgTasks )
                             gcnt += AddGhostZone( GetCallstack( sd.callstack.Val() ), &t->ghostZones, sd.time.Val() );
                         }
                     }
-                    std::lock_guard<std::shared_mutex> lock( m_data.lock );
+                    std::lock_guard<std::mutex> lock( m_data.lock );
                     m_data.ghostZonesReady = true;
                     m_data.ghostCnt = gcnt;
                 } ) );
@@ -1835,7 +1835,7 @@ Worker::Worker( FileRead& f, EventType::Type eventMask, bool bgTasks )
                     {
                         pdqsort_branchless( v.second.begin(), v.second.end(), []( const auto& lhs, const auto& rhs ) { return lhs.time.Val() < rhs.time.Val(); } );
                     }
-                    std::lock_guard<std::shared_mutex> lock( m_data.lock );
+                    std::lock_guard<std::mutex> lock( m_data.lock );
                     m_data.symbolSamplesReady = true;
                 } ) );
             }
@@ -1853,7 +1853,7 @@ Worker::Worker( FileRead& f, EventType::Type eventMask, bool bgTasks )
 #endif
             }
             {
-                std::lock_guard<std::shared_mutex> lock( m_data.lock );
+                std::lock_guard<std::mutex> lock( m_data.lock );
                 m_data.sourceLocationZonesReady = true;
             }
 
@@ -2779,7 +2779,7 @@ void Worker::Exec()
         const char* end = ptr + netbuf.size;
 
         {
-            std::lock_guard<std::shared_mutex> lock( m_data.lock );
+            std::lock_guard<std::mutex> lock( m_data.lock );
             while( ptr < end )
             {
                 auto ev = (const QueueItem*)ptr;
@@ -6223,7 +6223,7 @@ void Worker::ReconstructMemAllocPlot( MemData& mem )
 
     PlotData* plot;
     {
-        std::lock_guard<std::shared_mutex> lock( m_data.lock );
+        std::lock_guard<std::mutex> lock( m_data.lock );
         plot = m_slab.AllocInit<PlotData>();
     }
 
@@ -6307,7 +6307,7 @@ void Worker::ReconstructMemAllocPlot( MemData& mem )
     plot->min = 0;
     plot->max = max;
 
-    std::lock_guard<std::shared_mutex> lock( m_data.lock );
+    std::lock_guard<std::mutex> lock( m_data.lock );
     m_data.plots.Data().insert( m_data.plots.Data().begin(), plot );
     mem.plot = plot;
 }
@@ -6403,7 +6403,7 @@ void Worker::ReconstructContextSwitchUsage()
         }
     }
 
-    std::lock_guard<std::shared_mutex> lock( m_data.lock );
+    std::lock_guard<std::mutex> lock( m_data.lock );
     m_data.ctxUsageReady = true;
 }
 
diff --git a/server/TracyWorker.hpp b/server/TracyWorker.hpp
index 423366d1..f66e3d7c 100644
--- a/server/TracyWorker.hpp
+++ b/server/TracyWorker.hpp
@@ -233,7 +233,7 @@ private:
 
     struct DataBlock
     {
-        std::shared_mutex lock;
+        std::mutex lock;
         StringDiscovery<FrameData*> frames;
         FrameData* framesBase;
         Vector<GpuCtxData*> gpuData;
@@ -413,7 +413,7 @@ public:
     uint32_t GetCpuId() const { return m_data.cpuId; }
     const char* GetCpuManufacturer() const { return m_data.cpuManufacturer; }
 
-    std::shared_mutex& GetDataLock() { return m_data.lock; }
+    std::mutex& GetDataLock() { return m_data.lock; }
     size_t GetFrameCount( const FrameData& fd ) const { return fd.frames.size(); }
     size_t GetFullFrameCount( const FrameData& fd ) const;
     int64_t GetLastTime() const { return m_data.lastTime; }