Merge pull request #25137 from vespa-engine/toregge/use-atomic-thread-pointer-in-runnable

Use atomic thread pointer in runnable.

2 files changed, 5 insertions, 5 deletions

diff --git a/fastos/src/vespa/fastos/thread.cpp b/fastos/src/vespa/fastos/thread.cpp
index 7695ce3342e..d172977b222 100644
--- a/fastos/src/vespa/fastos/thread.cpp
+++ b/fastos/src/vespa/fastos/thread.cpp
@@ -308,7 +308,7 @@ void FastOS_ThreadInterface::Dispatch(FastOS_Runnable *newOwner, void *arg)
     _owner = newOwner;
     _startArg = arg;
     // Set _thread variable before NewThread returns
-    _owner->_thread = this;
+    _owner->_thread.store(this, std::memory_order_release);
 
     // It is safe to signal after the unlock since _liveCond is still held
     // so the signalled thread still exists.
diff --git a/fastos/src/vespa/fastos/thread.h b/fastos/src/vespa/fastos/thread.h
index 95737e9d079..a8cf12825eb 100644
--- a/fastos/src/vespa/fastos/thread.h
+++ b/fastos/src/vespa/fastos/thread.h
@@ -455,7 +455,7 @@ class FastOS_Runnable
 {
 private:
     friend class FastOS_ThreadInterface;
-    FastOS_ThreadInterface *_thread;
+    std::atomic<FastOS_ThreadInterface*> _thread;
 
 public:
     FastOS_Runnable(const FastOS_Runnable&) = delete;
@@ -482,9 +482,9 @@ public:
      */
     virtual void Run(FastOS_ThreadInterface *thisThread, void *arguments)=0;
 
-    FastOS_ThreadInterface *GetThread()             { return _thread; }
-    const FastOS_ThreadInterface *GetThread() const { return _thread; }
-    bool HasThread()                          const { return _thread != nullptr; }
+    FastOS_ThreadInterface *GetThread()             noexcept { return _thread.load(std::memory_order_acquire); }
+    const FastOS_ThreadInterface *GetThread() const noexcept { return _thread.load(std::memory_order_acquire); }
+    bool HasThread()                          const noexcept { return GetThread() != nullptr; }
 };
 
 #include <vespa/fastos/unix_thread.h>