[bench] allow parsing overhead linop

Author: MarcelKoch

benchmark/preconditioner/preconditioner.cpp

@@ -80,7 +80,7 @@ struct PreconditionerBenchmark : Benchmark<preconditioner_benchmark_state> {
         IterationControl ic_gen{get_timer(exec, FLAGS_gpu_timer)};
         IterationControl ic_apply{get_timer(exec, FLAGS_gpu_timer)};
 
-        auto context = gko::config::registry{};
+        auto context = create_default_registry();
         auto td = gko::config::make_type_descriptor<etype, itype>();
         auto preconditioner_config =
             gko::ext::config::parse_json(operation_case["preconditioner"]);

benchmark/solver/solver_common.hpp

@@ -226,7 +226,7 @@ struct SolverBenchmark : Benchmark<solver_benchmark_state<Generator>> {
         auto warmup_config =
             gko::ext::config::parse_json(warmup_case["solver"]);
 
-        auto registry = gko::config::registry{};
+        auto registry = create_default_registry();
         auto td = gko::config::make_type_descriptor<etype>();
 
         IterationControl ic{timer};

benchmark/utils/general.hpp

@@ -30,7 +30,9 @@
 #include "benchmark/utils/json.hpp"
 #include "benchmark/utils/timer.hpp"
 #include "benchmark/utils/types.hpp"
+#include "core/config/config_helper.hpp"
 #include "core/distributed/helpers.hpp"
+#include "overhead_linop.hpp"
 
 
 // Global command-line arguments
@@ -565,4 +567,21 @@ std::unique_ptr<VectorType> create_normalized_manufactured_rhs(
 }
 
 
+inline gko::config::registry create_default_registry()
+{
+    return {{{"overhead",
+              [](const gko::config::pnode& config,
+                 const gko::config::registry& context,
+                 gko::config::type_descriptor td_for_child)
+                  -> gko::deferred_factory_parameter<gko::LinOpFactory> {
+                  auto params = gko::Overhead<etype>::build();
+                  if (auto& obj = config.get("criteria")) {
+                      params.with_criteria(gko::config::parse_or_get_criteria(
+                          obj, context, td_for_child));
+                  }
+                  return params;
+              }}}};
+}
+
+
 #endif  // GKO_BENCHMARK_UTILS_GENERAL_HPP_

benchmark/utils/overhead_linop.hpp

@@ -1,4 +1,4 @@
-// SPDX-FileCopyrightText: 2017 - 2024 The Ginkgo authors
+// SPDX-FileCopyrightText: 2017 - 2025 The Ginkgo authors
 //
 // SPDX-License-Identifier: BSD-3-Clause
 
@@ -135,8 +135,10 @@ class Overhead : public EnableLinOp<Overhead<ValueType>>,
             set_preconditioner(matrix::Identity<ValueType>::create(
                 this->get_executor(), this->get_size()[0]));
         }
-        stop_criterion_factory_ =
-            stop::combine(std::move(parameters_.criteria));
+        if (!parameters_.criteria.empty()) {
+            stop_criterion_factory_ =
+                stop::combine(std::move(parameters_.criteria));
+        }
     }
 
 private: