Make storage framework thread tick ring buffer thread safe

2 files changed, 8 insertions, 5 deletions

diff --git a/storageframework/src/vespa/storageframework/defaultimplementation/thread/threadimpl.cpp b/storageframework/src/vespa/storageframework/defaultimplementation/thread/threadimpl.cpp
index 7281c55ba25..b8ef8e4610b 100644
--- a/storageframework/src/vespa/storageframework/defaultimplementation/thread/threadimpl.cpp
+++ b/storageframework/src/vespa/storageframework/defaultimplementation/thread/threadimpl.cpp
@@ -3,10 +3,13 @@
 #include "threadimpl.h"
 #include "threadpoolimpl.h"
 #include <vespa/storageframework/generic/clock/clock.h>
+#include <vespa/vespalib/util/atomic.h>
 
 #include <vespa/log/bufferedlogger.h>
 LOG_SETUP(".framework.thread.impl");
 
+using namespace vespalib::atomic;
+
 namespace storage::framework::defaultimplementation {
 
 ThreadImpl::ThreadImpl(ThreadPoolImpl& pool,
@@ -27,7 +30,7 @@ ThreadImpl::ThreadImpl(ThreadPoolImpl& pool,
       _thread(*this),
       _cpu_category(cpu_category)
 {
-    _tickData[_tickDataPtr]._lastTick = pool.getClock().getMonotonicTime();
+    _tickData[load_relaxed(_tickDataPtr)]._lastTick = pool.getClock().getMonotonicTime();
     _thread.start(_pool.getThreadPool());
 }
 
@@ -105,15 +108,15 @@ ThreadImpl::registerTick(CycleType cycleType, vespalib::steady_time now)
 ThreadTickData
 ThreadImpl::getTickData() const
 {
-    return _tickData[_tickDataPtr].loadRelaxed();
+    return _tickData[load_acquire(_tickDataPtr)].loadRelaxed();
 }
 
 void
 ThreadImpl::setTickData(const ThreadTickData& tickData)
 {
-    uint32_t nextData = (_tickDataPtr + 1) % _tickData.size();
+    uint32_t nextData = (load_relaxed(_tickDataPtr) + 1) % _tickData.size();
     _tickData[nextData].storeRelaxed(tickData);
-    _tickDataPtr = nextData;
+    store_release(_tickDataPtr, nextData);
 }
 
 ThreadTickData
diff --git a/storageframework/src/vespa/storageframework/defaultimplementation/thread/threadimpl.h b/storageframework/src/vespa/storageframework/defaultimplementation/thread/threadimpl.h
index e6f0a21ea20..46a9412bf67 100644
--- a/storageframework/src/vespa/storageframework/defaultimplementation/thread/threadimpl.h
+++ b/storageframework/src/vespa/storageframework/defaultimplementation/thread/threadimpl.h
@@ -49,7 +49,7 @@ class ThreadImpl : public Thread
     Runnable& _runnable;
     ThreadProperties _properties;
     std::array<AtomicThreadTickData, 3> _tickData;
-    uint32_t _tickDataPtr;
+    std::atomic<uint32_t> _tickDataPtr;
     std::atomic<bool> _interrupted;
     bool _joined;
     BackendThread _thread;