Port to stdexec

CMakeLists.txt

@@ -421,6 +421,25 @@ if( TRACCC_SETUP_INDICATORS )
    endif()
 endif()
 
+# Set up stdexec.
+option( TRACCC_SETUP_STDEXEC
+   "Set up the stdexec target(s) explicitly" TRUE )
+if (TRACCC_USE_SYSTEM_LIBS OR TRACCC_USE_SPACK_LIBS)
+   set(TRACCC_USE_SYSTEM_STDEXEC_DEFAULT ON)
+else()
+   set(TRACCC_USE_SYSTEM_STDEXEC_DEFAULT OFF)
+endif()
+option( TRACCC_USE_SYSTEM_STDEXEC
+   "Pick up an existing installation of stdexec from the build environment"
+   ${TRACCC_USE_SYSTEM_STDEXEC_DEFAULT} )
+unset(TRACCC_USE_SYSTEM_STDEXEC_DEFAULT)
+if( TRACCC_SETUP_STDEXEC )
+   if( TRACCC_USE_SYSTEM_STDEXEC )
+      find_package( stdexec REQUIRED )
+   else()
+      add_subdirectory( extern/stdexec )
+   endif()
+endif()
 
 option( TRACCC_ENABLE_NVTX_PROFILING
         "Use instrument functions to enable fine grained profiling" FALSE )

core/CMakeLists.txt

@@ -65,6 +65,8 @@ traccc_add_library( traccc_core core TYPE SHARED
   "include/traccc/utils/logging.hpp"
   "include/traccc/utils/prob.hpp"
   "src/utils/logging.cpp"
+  # Execution.
+  "include/traccc/execution/task.hpp"
   # Clusterization algorithmic code.
   "include/traccc/clusterization/details/sparse_ccl.hpp"
   "include/traccc/clusterization/impl/sparse_ccl.ipp"
@@ -138,7 +140,7 @@ traccc_add_library( traccc_core core TYPE SHARED
   "src/ambiguity_resolution/legacy/greedy_ambiguity_resolution_algorithm.cpp")
 target_link_libraries( traccc_core
   PUBLIC Eigen3::Eigen vecmem::core covfie::core detray::core detray::detectors
-         traccc::algebra Acts::Core )
+         traccc::algebra Acts::Core STDEXEC::stdexec )
 
 # Prevent Eigen from getting confused when building code for a
 # CUDA or HIP backend with SYCL.

core/include/traccc/execution/task.hpp

@@ -0,0 +1,10 @@
+#pragma once
+
+// Stdexec include(s).
+#include <exec/task.hpp>
+
+namespace traccc {
+
+template <typename T>
+using task = exec::task<T>;
+}

device/common/CMakeLists.txt

@@ -36,6 +36,7 @@ traccc_add_library( traccc_device_common device_common
    "include/traccc/clusterization/device/ccl_kernel.hpp"
    "include/traccc/clusterization/device/sorting_index_filler.hpp"
    "include/traccc/clusterization/device/clusterization_algorithm.hpp"
+   "include/traccc/clusterization/device/clusterization_kernel_payload.hpp"
    "src/clusterization/clusterization_algorithm.cpp"
    # Spacepoint binning function(s).
    "include/traccc/seeding/device/count_grid_capacities.hpp"
@@ -60,10 +61,13 @@ traccc_add_library( traccc_device_common device_common
    "include/traccc/seeding/device/select_seeds.hpp"
    "include/traccc/seeding/device/impl/select_seeds.ipp"
    "include/traccc/seeding/device/triplet_seeding_algorithm.hpp"
+   "include/traccc/seeding/device/triplet_seeding_kernel_payloads.hpp"
    "src/seeding/triplet_seeding_algorithm.cpp"
    "include/traccc/seeding/device/silicon_pixel_spacepoint_formation_algorithm.hpp"
+   "include/traccc/seeding/device/silicon_pixel_spacepoint_formation_kernel_payload.hpp"
    "src/seeding/silicon_pixel_spacepoint_formation_algorithm.cpp"
    "include/traccc/seeding/device/seed_parameter_estimation_algorithm.hpp"
+   "include/traccc/seeding/device/seed_parameter_estimation_kernel_payload.hpp"
    "src/seeding/seed_parameter_estimation_algorithm.cpp"
    # Track parameters estimation function(s).
    "include/traccc/seeding/device/estimate_track_params.hpp"

device/common/include/traccc/clusterization/device/clusterization_algorithm.hpp

@@ -9,8 +9,10 @@
 
 // Local include(s).
 #include "traccc/clusterization/device/ccl_kernel_definitions.hpp"
+#include "traccc/clusterization/device/clusterization_kernel_payload.hpp"
 #include "traccc/clusterization/device/tags.hpp"
 #include "traccc/device/algorithm_base.hpp"
+#include "traccc/execution/task.hpp"
 
 // Project include(s).
 #include "traccc/clusterization/clustering_config.hpp"
@@ -41,16 +43,18 @@ namespace traccc::device {
 /// synchronisation statement is required before destroying the buffer.
 ///
 class clusterization_algorithm
-    : public algorithm<edm::measurement_collection<default_algebra>::buffer(
-          const edm::silicon_cell_collection::const_view&,
-          const silicon_detector_description::const_view&)>,
-      public algorithm<edm::measurement_collection<default_algebra>::buffer(
-          const edm::silicon_cell_collection::const_view&,
-          const silicon_detector_description::const_view&,
-          clustering_discard_disjoint_set&&)>,
+    : public algorithm<
+          task<edm::measurement_collection<default_algebra>::buffer>(
+              const edm::silicon_cell_collection::const_view&,
+              const silicon_detector_description::const_view&)>,
+      public algorithm<
+          task<edm::measurement_collection<default_algebra>::buffer>(
+              const edm::silicon_cell_collection::const_view&,
+              const silicon_detector_description::const_view&,
+              clustering_discard_disjoint_set&&)>,
       public algorithm<
-          std::pair<edm::measurement_collection<default_algebra>::buffer,
-                    edm::silicon_cluster_collection::buffer>(
+          task<std::pair<edm::measurement_collection<default_algebra>::buffer,
+                         edm::silicon_cluster_collection::buffer>>(
               const edm::silicon_cell_collection::const_view&,
               const silicon_detector_description::const_view&,
               clustering_keep_disjoint_set&&)>,
@@ -81,18 +85,18 @@ class clusterization_algorithm
     /// @return a measurement collection (buffer)
     ///
     /// @{
-    edm::measurement_collection<default_algebra>::buffer operator()(
+    task<edm::measurement_collection<default_algebra>::buffer> operator()(
         const edm::silicon_cell_collection::const_view& cells,
         const silicon_detector_description::const_view& det_descr)
         const override;
 
-    edm::measurement_collection<default_algebra>::buffer operator()(
+    task<edm::measurement_collection<default_algebra>::buffer> operator()(
         const edm::silicon_cell_collection::const_view& cells,
         const silicon_detector_description::const_view& det_descr,
         clustering_discard_disjoint_set&&) const override;
 
-    std::pair<edm::measurement_collection<default_algebra>::buffer,
-              edm::silicon_cluster_collection::buffer>
+    task<std::pair<edm::measurement_collection<default_algebra>::buffer,
+                   edm::silicon_cluster_collection::buffer>>
     operator()(const edm::silicon_cell_collection::const_view& cells,
                const silicon_detector_description::const_view& det_descr,
                clustering_keep_disjoint_set&&) const override;
@@ -111,34 +115,7 @@ class clusterization_algorithm
         const edm::silicon_cell_collection::const_view& cells) const = 0;
 
     /// Payload for the @c ccl_kernel function
-    struct ccl_kernel_payload {
-        /// Number of cells in the event
-        unsigned int n_cells;
-        /// The clustering configuration
-        const config_type& config;
-        /// All cells in an event
-        const edm::silicon_cell_collection::const_view& cells;
-        /// The detector description
-        const silicon_detector_description::const_view& det_descr;
-        /// The measurement collection to fill
-        edm::measurement_collection<default_algebra>::view& measurements;
-        /// Buffer for linking cells to measurements
-        vecmem::data::vector_view<unsigned int>& cell_links;
-        /// Buffer for backup of the first element links
-        vecmem::data::vector_view<details::index_t>& f_backup;
-        /// Buffer for backup of the group first element links
-        vecmem::data::vector_view<details::index_t>& gf_backup;
-        /// Buffer for backup of the adjacency matrix (counts)
-        vecmem::data::vector_view<unsigned char>& adjc_backup;
-        /// Buffer for backup of the adjacency matrix (values)
-        vecmem::data::vector_view<details::index_t>& adjv_backup;
-        /// Mutex for the backup structures
-        unsigned int* backup_mutex;
-        /// Buffer for the disjoint set data structure
-        vecmem::data::vector_view<unsigned int>& disjoint_set;
-        /// Buffer for the sizes of the clusters
-        vecmem::data::vector_view<unsigned int>& cluster_sizes;
-    };
+    using ccl_kernel_payload = clusterization_ccl_kernel_payload;
 
     /// Main CCL kernel launcher
     ///
@@ -159,13 +136,13 @@ class clusterization_algorithm
 
     /// @}
 
-    /// Possibly suspend execution until all asynchronous operations are done
-    virtual void await(vecmem::abstract_event& event) const = 0;
+    /// Suspend execution until all asynchronous operations are done
+    virtual task<void> await(vecmem::abstract_event& event) const = 0;
 
     private:
     /// Main algorithmic implementation of the clusterization algorithm
-    std::pair<edm::measurement_collection<default_algebra>::buffer,
-              std::optional<edm::silicon_cluster_collection::buffer>>
+    task<std::pair<edm::measurement_collection<default_algebra>::buffer,
+                   std::optional<edm::silicon_cluster_collection::buffer>>>
     execute_impl(const edm::silicon_cell_collection::const_view& cells,
                  const silicon_detector_description::const_view& det_descr,
                  bool keep_disjoint_set) const;

device/common/include/traccc/clusterization/device/clusterization_kernel_payload.hpp

@@ -0,0 +1,53 @@
+/** TRACCC library, part of the ACTS project (R&D line)
+ *
+ * (c) 2022-2026 CERN for the benefit of the ACTS project
+ *
+ * Mozilla Public License Version 2.0
+ */
+
+#pragma once
+
+// Project include(s).
+#include "traccc/clusterization/clustering_config.hpp"
+#include "traccc/clusterization/device/ccl_kernel_definitions.hpp"
+#include "traccc/edm/measurement_collection.hpp"
+#include "traccc/edm/silicon_cell_collection.hpp"
+#include "traccc/geometry/silicon_detector_description.hpp"
+
+// VecMem include(s).
+#include <vecmem/containers/data/vector_view.hpp>
+
+namespace traccc::device {
+
+/// Payload for the @c traccc::device::clusterization_algorithm::ccl_kernel
+/// function.
+struct clusterization_ccl_kernel_payload {
+    /// Number of cells in the event
+    unsigned int n_cells;
+    /// The clustering configuration
+    const clustering_config& config;
+    /// All cells in an event
+    const edm::silicon_cell_collection::const_view& cells;
+    /// The detector description
+    const silicon_detector_description::const_view& det_descr;
+    /// The measurement collection to fill
+    edm::measurement_collection<default_algebra>::view& measurements;
+    /// Buffer for linking cells to measurements
+    vecmem::data::vector_view<unsigned int>& cell_links;
+    /// Buffer for backup of the first element links
+    vecmem::data::vector_view<details::index_t>& f_backup;
+    /// Buffer for backup of the group first element links
+    vecmem::data::vector_view<details::index_t>& gf_backup;
+    /// Buffer for backup of the adjacency matrix (counts)
+    vecmem::data::vector_view<unsigned char>& adjc_backup;
+    /// Buffer for backup of the adjacency matrix (values)
+    vecmem::data::vector_view<details::index_t>& adjv_backup;
+    /// Mutex for the backup structures
+    unsigned int* backup_mutex;
+    /// Buffer for the disjoint set data structure
+    vecmem::data::vector_view<unsigned int>& disjoint_set;
+    /// Buffer for the sizes of the clusters
+    vecmem::data::vector_view<unsigned int>& cluster_sizes;
+};
+
+}  // namespace traccc::device

device/common/include/traccc/seeding/device/seed_parameter_estimation_algorithm.hpp

@@ -9,6 +9,8 @@
 
 // Local include(s).
 #include "traccc/device/algorithm_base.hpp"
+#include "traccc/execution/task.hpp"
+#include "traccc/seeding/device/seed_parameter_estimation_kernel_payload.hpp"
 
 // Project include(s)
 #include "traccc/bfield/magnetic_field.hpp"
@@ -29,7 +31,7 @@ namespace traccc::device {
 /// synchronisation statement is required before destroying this buffer.
 ///
 struct seed_parameter_estimation_algorithm
-    : public algorithm<bound_track_parameters_collection_types::buffer(
+    : public algorithm<task<bound_track_parameters_collection_types::buffer>(
           const magnetic_field&,
           const edm::measurement_collection<default_algebra>::const_view&,
           const edm::spacepoint_collection::const_view&,
@@ -59,7 +61,8 @@ struct seed_parameter_estimation_algorithm
     /// @param measurements All measurements of the event
     /// @param spacepoints All spacepoints of the event
     /// @param seeds The reconstructed track seeds of the event
-    /// @return A vector of bound track parameters for the seeds
+    /// @return A task returning a vector of bound track parameters for the
+    /// seeds
     ///
     output_type operator()(
         const magnetic_field& bfield,
@@ -73,35 +76,20 @@ struct seed_parameter_estimation_algorithm
     /// @{
 
     /// Payload for the @c estimate_seed_params_kernel function
-    struct estimate_seed_params_kernel_payload {
-        /// The number of seeds
-        edm::seed_collection::const_view::size_type n_seeds;
-        /// The track parameter estimation configuration
-        const track_params_estimation_config& config;
-        /// The magnetic field object
-        const magnetic_field& bfield;
-        /// All measurements of the event
-        const edm::measurement_collection<default_algebra>::const_view&
-            measurements;
-        /// All spacepoints of the event
-        const edm::spacepoint_collection::const_view& spacepoints;
-        /// The reconstructed track seeds of the event
-        const edm::seed_collection::const_view& seeds;
-        /// The output buffer for the bound track parameters
-        bound_track_parameters_collection_types::view& params;
-    };
+    using estimate_seed_params_kernel_payload =
+        struct traccc::device::estimate_seed_params_kernel_payload;
 
     /// Seed parameter estimation kernel launcher
     ///
     /// @param payload The payload for the kernel
     ///
     virtual void estimate_seed_params_kernel(
-        const struct estimate_seed_params_kernel_payload& payload) const = 0;
+        const estimate_seed_params_kernel_payload& payload) const = 0;
 
     /// @}
 
-    /// Possibly suspend execution until all asynchronous operations are done
-    virtual void await(vecmem::abstract_event& event) const = 0;
+    /// Suspend execution until all asynchronous operations are done
+    virtual task<void> await(vecmem::abstract_event& event) const = 0;
 
     private:
     /// Internal data type

device/common/include/traccc/seeding/device/seed_parameter_estimation_kernel_payload.hpp

@@ -0,0 +1,40 @@
+/** TRACCC library, part of the ACTS project (R&D line)
+ *
+ * (c) 2021-2026 CERN for the benefit of the ACTS project
+ *
+ * Mozilla Public License Version 2.0
+ */
+
+#pragma once
+
+// Project include(s)
+#include "traccc/bfield/magnetic_field.hpp"
+#include "traccc/edm/measurement_collection.hpp"
+#include "traccc/edm/seed_collection.hpp"
+#include "traccc/edm/spacepoint_collection.hpp"
+#include "traccc/edm/track_parameters.hpp"
+#include "traccc/seeding/detail/track_params_estimation_config.hpp"
+
+namespace traccc::device {
+
+/// Payload for the
+/// @c seed_parameter_estimation_algorithm::estimate_seed_params_kernel function
+struct estimate_seed_params_kernel_payload {
+    /// The number of seeds
+    edm::seed_collection::const_view::size_type n_seeds;
+    /// The track parameter estimation configuration
+    const track_params_estimation_config& config;
+    /// The magnetic field object
+    const magnetic_field& bfield;
+    /// All measurements of the event
+    const edm::measurement_collection<default_algebra>::const_view&
+        measurements;
+    /// All spacepoints of the event
+    const edm::spacepoint_collection::const_view& spacepoints;
+    /// The reconstructed track seeds of the event
+    const edm::seed_collection::const_view& seeds;
+    /// The output buffer for the bound track parameters
+    bound_track_parameters_collection_types::view& params;
+};
+
+}  // namespace traccc::device