[release/8.0] Free the tls memory on thread termination (#95439)

* Free the tls memory

* zero the size variables

* fix linux build errors

* Move ThreadStaticBlockInfo definition in jitinterface.h

* cleanup and consolidate TLS variables

* Address review feedback

* reset t_NonGCThreadStaticBlocksSize and conditional check the nullptr

* Delete tls memory from detach thread

* Call DeleteThreadLocalMemory() from TlsDestructionMonitor

---------

Co-authored-by: Kunal Pathak <[email protected]>

Author: github-actions[bot]

src/coreclr/vm/ceemain.cpp

@@ -1752,6 +1752,7 @@ struct TlsDestructionMonitor
                     GCX_COOP_NO_DTOR_END();
                 }
                 thread->DetachThread(TRUE);
+                DeleteThreadLocalMemory();
             }
 
             ThreadDetaching();
@@ -1768,6 +1769,35 @@ void EnsureTlsDestructionMonitor()
     tls_destructionMonitor.Activate();
 }
 
+#ifdef _MSC_VER
+__declspec(thread)  ThreadStaticBlockInfo t_ThreadStatics;
+#else
+__thread ThreadStaticBlockInfo t_ThreadStatics;
+#endif // _MSC_VER
+
+// Delete the thread local memory only if we the current thread
+// is the one executing this code. If we do not guard it, it will
+// end up deleting the thread local memory of the calling thread.
+void DeleteThreadLocalMemory()
+{
+    t_NonGCThreadStaticBlocksSize = 0;
+    t_GCThreadStaticBlocksSize = 0;
+
+    t_ThreadStatics.NonGCMaxThreadStaticBlocks = 0;
+    t_ThreadStatics.GCMaxThreadStaticBlocks = 0;
+
+    if (t_ThreadStatics.NonGCThreadStaticBlocks != nullptr)
+    {
+        delete[] t_ThreadStatics.NonGCThreadStaticBlocks;
+        t_ThreadStatics.NonGCThreadStaticBlocks = nullptr;
+    }
+    if (t_ThreadStatics.GCThreadStaticBlocks != nullptr)
+    {
+        delete[] t_ThreadStatics.GCThreadStaticBlocks;
+        t_ThreadStatics.GCThreadStaticBlocks = nullptr;
+    }
+}
+
 #ifdef DEBUGGING_SUPPORTED
 //
 // InitializeDebugger initialized the Runtime-side COM+ Debugging Services

src/coreclr/vm/ceemain.h

@@ -47,6 +47,8 @@ void ThreadDetaching();
 
 void EnsureTlsDestructionMonitor();
 
+void DeleteThreadLocalMemory();
+
 void SetLatchedExitCode (INT32 code);
 INT32 GetLatchedExitCode (void);
 

src/coreclr/vm/jithelpers.cpp

@@ -1777,24 +1777,13 @@ HCIMPL1(void*, JIT_GetGCThreadStaticBase_Helper, MethodTable * pMT)
 }
 HCIMPLEND
 
-struct ThreadStaticBlockInfo
-{
-    uint32_t NonGCMaxThreadStaticBlocks;
-    void** NonGCThreadStaticBlocks;
-
-    uint32_t GCMaxThreadStaticBlocks;
-    void** GCThreadStaticBlocks;
-};
-
 #ifdef _MSC_VER
-__declspec(selectany) __declspec(thread)  ThreadStaticBlockInfo t_ThreadStatics;
-__declspec(selectany) __declspec(thread)  uint32_t t_NonGCThreadStaticBlocksSize;
-__declspec(selectany) __declspec(thread)  uint32_t t_GCThreadStaticBlocksSize;
+__declspec(thread)  uint32_t t_NonGCThreadStaticBlocksSize;
+__declspec(thread)  uint32_t t_GCThreadStaticBlocksSize;
 #else
-EXTERN_C __thread ThreadStaticBlockInfo t_ThreadStatics;
-EXTERN_C __thread uint32_t t_NonGCThreadStaticBlocksSize;
-EXTERN_C __thread uint32_t t_GCThreadStaticBlocksSize;
-#endif
+__thread uint32_t t_NonGCThreadStaticBlocksSize;
+__thread uint32_t t_GCThreadStaticBlocksSize;
+#endif // !_MSC_VER
 
 // *** This helper corresponds to both CORINFO_HELP_GETSHARED_NONGCTHREADSTATIC_BASE and
 //     CORINFO_HELP_GETSHARED_NONGCTHREADSTATIC_BASE_NOCTOR. Even though we always check

src/coreclr/vm/jitinterface.cpp

@@ -69,24 +69,9 @@
 EXTERN_C uint32_t _tls_index;
 #endif
 
-struct ThreadStaticBlockInfo
-{
-    uint32_t NonGCMaxThreadStaticBlocks;
-    void** NonGCThreadStaticBlocks;
-
-    uint32_t GCMaxThreadStaticBlocks;
-    void** GCThreadStaticBlocks;
-};
-#ifdef _MSC_VER
-__declspec(selectany) __declspec(thread)  ThreadStaticBlockInfo t_ThreadStatics;
-__declspec(selectany) __declspec(thread)  uint32_t t_NonGCThreadStaticBlocksSize;
-__declspec(selectany) __declspec(thread)  uint32_t t_GCThreadStaticBlocksSize;
-#else
+#ifndef _MSC_VER
 extern "C" void* __tls_get_addr(void* ti);
-__thread ThreadStaticBlockInfo t_ThreadStatics;
-__thread uint32_t t_NonGCThreadStaticBlocksSize;
-__thread uint32_t t_GCThreadStaticBlocksSize;
-#endif // _MSC_VER
+#endif // !_MSC_VER
 
 // The Stack Overflow probe takes place in the COOPERATIVE_TRANSITION_BEGIN() macro
 //

src/coreclr/vm/jitinterface.h

@@ -101,6 +101,25 @@ BOOL LoadDynamicInfoEntry(Module *currentModule,
 
 #endif // TARGET_X86
 
+// thread local struct to store the "thread static blocks"
+struct ThreadStaticBlockInfo
+{
+    uint32_t NonGCMaxThreadStaticBlocks;
+    void** NonGCThreadStaticBlocks;
+
+    uint32_t GCMaxThreadStaticBlocks;
+    void** GCThreadStaticBlocks;
+};
+
+#ifdef _MSC_VER
+EXTERN_C __declspec(thread)  ThreadStaticBlockInfo t_ThreadStatics;
+EXTERN_C __declspec(thread)  uint32_t t_NonGCThreadStaticBlocksSize;
+EXTERN_C __declspec(thread)  uint32_t t_GCThreadStaticBlocksSize;
+#else
+EXTERN_C __thread ThreadStaticBlockInfo t_ThreadStatics;
+EXTERN_C __thread uint32_t t_NonGCThreadStaticBlocksSize;
+EXTERN_C __thread uint32_t t_GCThreadStaticBlocksSize;
+#endif // _MSC_VER
 
 //
 // JIT HELPER ALIASING FOR PORTABILITY.