From 4c47ad8a6bbe6715d63cd42e9c035f0d37bcaf02 Mon Sep 17 00:00:00 2001
From: Alex Lindsay <alexander.lindsay@inl.gov>
Date: Mon, 24 Jun 2024 07:57:40 -0700
Subject: [PATCH 1/3] Use rvalue ref unique_ptr for restore_subvector

---
 include/numerics/numeric_vector.h    | 3 ++-
 include/numerics/petsc_vector.h      | 2 +-
 src/numerics/petsc_vector.C          | 4 ++--
 src/systems/condensed_eigen_system.C | 4 ++--
 4 files changed, 7 insertions(+), 6 deletions(-)

diff --git a/include/numerics/numeric_vector.h b/include/numerics/numeric_vector.h
index 0ac3de4cec7..7b72e3d61c2 100644
--- a/include/numerics/numeric_vector.h
+++ b/include/numerics/numeric_vector.h
@@ -749,7 +749,8 @@ class NumericVector : public ReferenceCountedObject<NumericVector<T>>,
    * rows.  This  is currently only implemented for
    * PetscVectors.
    */
-  virtual void restore_subvector(NumericVector<T> &&, const std::vector<numeric_index_type> &)
+  virtual void restore_subvector(std::unique_ptr<NumericVector<T>> &&,
+                                 const std::vector<numeric_index_type> &)
   {
     libmesh_not_implemented();
   }
diff --git a/include/numerics/petsc_vector.h b/include/numerics/petsc_vector.h
index 19320538ac1..c04fdaf099b 100644
--- a/include/numerics/petsc_vector.h
+++ b/include/numerics/petsc_vector.h
@@ -349,7 +349,7 @@ class PetscVector final : public NumericVector<T>
   virtual std::unique_ptr<NumericVector<T>>
   get_subvector(const std::vector<numeric_index_type> & rows) override;
 
-  virtual void restore_subvector(NumericVector<T> && subvector,
+  virtual void restore_subvector(std::unique_ptr<NumericVector<T>> && subvector,
                                  const std::vector<numeric_index_type> & rows) override;
 
 private:
diff --git a/src/numerics/petsc_vector.C b/src/numerics/petsc_vector.C
index 494a9dd7d89..956e868c4b9 100644
--- a/src/numerics/petsc_vector.C
+++ b/src/numerics/petsc_vector.C
@@ -1431,10 +1431,10 @@ PetscVector<T>::get_subvector(const std::vector<numeric_index_type> & rows)
 
 template <typename T>
 void
-PetscVector<T>::restore_subvector(NumericVector<T> && subvector,
+PetscVector<T>::restore_subvector(std::unique_ptr<NumericVector<T>> && subvector,
                                   const std::vector<numeric_index_type> & rows)
 {
-  auto * const petsc_subvector = cast_ptr<PetscVector<T> *>(&subvector);
+  auto * const petsc_subvector = cast_ptr<PetscVector<T> *>(subvector.get());
 
   // Construct index set
   WrappedPetsc<IS> parent_is;
diff --git a/src/systems/condensed_eigen_system.C b/src/systems/condensed_eigen_system.C
index 9ff89e5fc41..65301521d5b 100644
--- a/src/systems/condensed_eigen_system.C
+++ b/src/systems/condensed_eigen_system.C
@@ -267,7 +267,7 @@ CondensedEigenSystem::copy_sub_to_super(const NumericVector<Number> & sub,
                           super.local_size());
   auto super_sub_view = super.get_subvector(local_non_condensed_dofs_vector);
   *super_sub_view = sub;
-  super.restore_subvector(std::move(*super_sub_view), local_non_condensed_dofs_vector);
+  super.restore_subvector(std::move(super_sub_view), local_non_condensed_dofs_vector);
 }
 
 void
@@ -279,7 +279,7 @@ CondensedEigenSystem::copy_super_to_sub(NumericVector<Number> & super,
                           super.local_size());
   auto super_sub_view = super.get_subvector(local_non_condensed_dofs_vector);
   sub = *super_sub_view;
-  super.restore_subvector(std::move(*super_sub_view), local_non_condensed_dofs_vector);
+  super.restore_subvector(std::move(super_sub_view), local_non_condensed_dofs_vector);
 }
 
 void

From 89d70d3c6137b402d2b22642fd167ee5750cec55 Mon Sep 17 00:00:00 2001
From: Alex Lindsay <alexander.lindsay@inl.gov>
Date: Tue, 25 Jun 2024 13:14:35 -0700
Subject: [PATCH 2/3] When restoring a subvector, we must make sure to update
 ghost entries

---
 src/numerics/petsc_vector.C | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/src/numerics/petsc_vector.C b/src/numerics/petsc_vector.C
index 956e868c4b9..53604aa28cb 100644
--- a/src/numerics/petsc_vector.C
+++ b/src/numerics/petsc_vector.C
@@ -1426,6 +1426,8 @@ PetscVector<T>::get_subvector(const std::vector<numeric_index_type> & rows)
   ierr = VecGetSubVector(_vec, parent_is, &subvec);
   LIBMESH_CHKERR(ierr);
 
+  this->_is_closed = false;
+
   return std::make_unique<PetscVector<T>>(subvec, this->comm());
 }
 
@@ -1448,6 +1450,11 @@ PetscVector<T>::restore_subvector(std::unique_ptr<NumericVector<T>> && subvector
   Vec subvec = petsc_subvector->vec();
   ierr = VecRestoreSubVector(_vec, parent_is, &subvec);
   LIBMESH_CHKERR(ierr);
+
+  if (this->type() == GHOSTED)
+    VecGhostUpdateBeginEnd(this->comm(), _vec, INSERT_VALUES, SCATTER_FORWARD);
+
+  this->_is_closed = true;
 }
 
 //------------------------------------------------------------------

From eaa757fb7de7844614f08c1fa13bba1c1c5f189c Mon Sep 17 00:00:00 2001
From: Alex Lindsay <alexander.lindsay@inl.gov>
Date: Tue, 2 Jul 2024 06:50:30 -0700
Subject: [PATCH 3/3] Pass by value instead of rvalue ref

This ensures the move constructor is invoked and the caller releases
ownership per https://stackoverflow.com/a/71930927
---
 include/numerics/numeric_vector.h | 2 +-
 include/numerics/petsc_vector.h   | 2 +-
 src/numerics/petsc_vector.C       | 2 +-
 3 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/include/numerics/numeric_vector.h b/include/numerics/numeric_vector.h
index 7b72e3d61c2..e9a7097ebdf 100644
--- a/include/numerics/numeric_vector.h
+++ b/include/numerics/numeric_vector.h
@@ -749,7 +749,7 @@ class NumericVector : public ReferenceCountedObject<NumericVector<T>>,
    * rows.  This  is currently only implemented for
    * PetscVectors.
    */
-  virtual void restore_subvector(std::unique_ptr<NumericVector<T>> &&,
+  virtual void restore_subvector(std::unique_ptr<NumericVector<T>>,
                                  const std::vector<numeric_index_type> &)
   {
     libmesh_not_implemented();
diff --git a/include/numerics/petsc_vector.h b/include/numerics/petsc_vector.h
index c04fdaf099b..4843109f3fd 100644
--- a/include/numerics/petsc_vector.h
+++ b/include/numerics/petsc_vector.h
@@ -349,7 +349,7 @@ class PetscVector final : public NumericVector<T>
   virtual std::unique_ptr<NumericVector<T>>
   get_subvector(const std::vector<numeric_index_type> & rows) override;
 
-  virtual void restore_subvector(std::unique_ptr<NumericVector<T>> && subvector,
+  virtual void restore_subvector(std::unique_ptr<NumericVector<T>> subvector,
                                  const std::vector<numeric_index_type> & rows) override;
 
 private:
diff --git a/src/numerics/petsc_vector.C b/src/numerics/petsc_vector.C
index 53604aa28cb..43de8c3f2f8 100644
--- a/src/numerics/petsc_vector.C
+++ b/src/numerics/petsc_vector.C
@@ -1433,7 +1433,7 @@ PetscVector<T>::get_subvector(const std::vector<numeric_index_type> & rows)
 
 template <typename T>
 void
-PetscVector<T>::restore_subvector(std::unique_ptr<NumericVector<T>> && subvector,
+PetscVector<T>::restore_subvector(std::unique_ptr<NumericVector<T>> subvector,
                                   const std::vector<numeric_index_type> & rows)
 {
   auto * const petsc_subvector = cast_ptr<PetscVector<T> *>(subvector.get());