Merge pull request mfem#4504 from helloworld922/master

Fix CUDA-enabled HYPRE finalization order issue

general/device.cpp

@@ -150,6 +150,9 @@ Device::Device()
 
 Device::~Device()
 {
+#ifdef MFEM_USE_MPI
+   Hypre::Finalize();
+#endif
    if ( device_env && !destroy_mm) { return; }
    if (!device_env &&  destroy_mm && !mem_host_env)
    {
@@ -255,7 +258,15 @@ void Device::Configure(const std::string &device, const int device_id)
    destroy_mm = true;
 
 #ifdef MFEM_USE_MPI
-   Hypre::InitDevice();
+#if defined(HYPRE_USING_GPU) && (MFEM_HYPRE_VERSION >= 23100)
+   // Skip the call to Hypre::InitDevice() if HYPRE is not initialized, e.g.
+   // * if running a serial code
+   // * if running with the environment variable MFEM_DEVICE set.
+   if (HYPRE_Initialized())
+   {
+      Hypre::InitDevice();
+   }
+#endif
 #endif
 }
 

linalg/hypre.cpp

@@ -28,16 +28,23 @@ namespace mfem
 {
 
 bool Hypre::configure_runtime_policy_from_mfem = true;
+Hypre::State Hypre::state = Hypre::State::UNINITIALIZED;
 
-Hypre::Hypre()
+void Hypre::Init()
 {
+   if (state != State::INITIALIZED)
+   {
 #if MFEM_HYPRE_VERSION >= 21900
-   // Initializing hypre
-   HYPRE_Init();
+      HYPRE_Init();
 #endif
-
-   // Global hypre options that we set by default
-   SetDefaultOptions();
+      SetDefaultOptions();
+      // Apply the setting of 'configure_runtime_policy_from_mfem' according to
+      // the current configuration of the mfem::Device (HYPRE >= 2.31.0):
+      InitDevice();
+      // Create the singleton Hypre object AFTER initializing HYPRE:
+      Instance();
+   }
+   state = State::INITIALIZED;
 }
 
 void Hypre::InitDevice()
@@ -48,6 +55,8 @@ void Hypre::InitDevice()
 #if defined(HYPRE_USING_GPU) && (MFEM_HYPRE_VERSION >= 23100)
    if (configure_runtime_policy_from_mfem)
    {
+      MFEM_VERIFY(HYPRE_Initialized(), "HYPRE must be initialized before"
+                  " calling Hypre::InitDevice()");
       if (Device::Allows(Backend::DEVICE_MASK & ~Backend::DEBUG_DEVICE))
       {
          HYPRE_SetMemoryLocation(HYPRE_MEMORY_DEVICE);
@@ -65,14 +74,13 @@ void Hypre::InitDevice()
 
 void Hypre::Finalize()
 {
-   Hypre &hypre = Instance();
-   if (!hypre.finalized)
+   if (state != State::UNINITIALIZED)
    {
 #if MFEM_HYPRE_VERSION >= 21900
       HYPRE_Finalize();
 #endif
-      hypre.finalized = true;
    }
+   state = State::UNINITIALIZED;
 }
 
 void Hypre::SetDefaultOptions()

linalg/hypre.hpp

@@ -68,10 +68,11 @@ class Hypre
 public:
    /// @brief Initialize hypre by calling HYPRE_Init() and set default options.
    /// After calling Hypre::Init(), hypre will be finalized automatically at
-   /// program exit.
+   /// program exit. May be re-initialized after finalize.
    ///
-   /// Calling HYPRE_Finalize() manually is not compatible with this class.
-   static void Init() { Instance(); }
+   /// Calling HYPRE_Init() or HYPRE_Finalize() manually is only supported for
+   /// HYPRE 2.29.0+
+   static void Init();
 
    /// @brief Configure HYPRE's compute and memory policy.
    ///
@@ -94,6 +95,9 @@ class Hypre
    ///
    /// Multiple calls to Hypre::Finalize() have no effect. This function can be
    /// called manually to more precisely control when hypre is finalized.
+   ///
+   /// Calling HYPRE_Init() or HYPRE_Finalize() manually is only supported for
+   /// HYPRE 2.29.0+
    static void Finalize();
 
    /// @brief Use MFEM's device policy to configure HYPRE's device policy, true
@@ -104,14 +108,20 @@ class Hypre
    static bool configure_runtime_policy_from_mfem;
 
 private:
-   /// Calls HYPRE_Init() when the singleton is constructed.
-   Hypre();
+   /// Default constructor. Singleton object; private.
+   Hypre() = default;
+
+   /// Copy constructor. Deleted.
+   Hypre(Hypre&) = delete;
+
+   /// Move constructor. Deleted.
+   Hypre(Hypre&&) = delete;
 
    /// The singleton destructor (called at program exit) finalizes hypre.
    ~Hypre() { Finalize(); }
 
    /// Set the default hypre global options (mostly GPU-relevant).
-   void SetDefaultOptions();
+   static void SetDefaultOptions();
 
    /// Create and return the Hypre singleton object.
    static Hypre &Instance()
@@ -120,7 +130,10 @@ class Hypre
       return hypre;
    }
 
-   bool finalized = false; ///< Has Hypre::Finalize() been called already?
+   enum class State { UNINITIALIZED, INITIALIZED };
+
+   /// Tracks whether Hypre was initialized or finalized by this class.
+   static State state;
 };