Investigating partitioned_vector problems

- flyby: reduce the need for make_ready_future for various AGAS operations

components/containers/partitioned_vector/include/hpx/components/containers/partitioned_vector/partitioned_vector_component_impl.hpp

@@ -1,5 +1,5 @@
 //  Copyright (c) 2014 Anuj R. Sharma
-//  Copyright (c) 2014-2017 Hartmut Kaiser
+//  Copyright (c) 2014-2022 Hartmut Kaiser
 //
 //  SPDX-License-Identifier: BSL-1.0
 //  Distributed under the Boost Software License, Version 1.0. (See accompanying
@@ -339,8 +339,8 @@ namespace hpx {
         partitioned_vector_partition<T, Data>::get_ptr() const
     {
         error_code ec(throwmode::lightweight);
-        return hpx::get_ptr<server::partitioned_vector<T, Data>>(this->get_id())
-            .get(ec);
+        return hpx::get_ptr<server::partitioned_vector<T, Data>>(
+            hpx::launch::sync, this->get_id(), ec);
     }
 
     template <typename T, typename Data /*= std::vector<T> */>

components/containers/partitioned_vector/include/hpx/components/containers/partitioned_vector/partitioned_vector_decl.hpp

@@ -1,5 +1,5 @@
 //  Copyright (c) 2014 Anuj R. Sharma
-//  Copyright (c) 2014-2017 Hartmut Kaiser
+//  Copyright (c) 2014-2022 Hartmut Kaiser
 //
 //  SPDX-License-Identifier: BSL-1.0
 //  Distributed under the Boost Software License, Version 1.0. (See accompanying

components/containers/partitioned_vector/include/hpx/components/containers/partitioned_vector/partitioned_vector_impl.hpp

@@ -1,5 +1,5 @@
 //  Copyright (c) 2014 Anuj R. Sharma
-//  Copyright (c) 2014-2017 Hartmut Kaiser
+//  Copyright (c) 2014-2022 Hartmut Kaiser
 //
 //  SPDX-License-Identifier: BSL-1.0
 //  Distributed under the Boost Software License, Version 1.0. (See accompanying
@@ -12,7 +12,6 @@
 #include <hpx/assert.hpp>
 #include <hpx/async_base/launch_policy.hpp>
 #include <hpx/async_combinators/wait_all.hpp>
-#include <hpx/async_combinators/when_all.hpp>
 #include <hpx/components/client_base.hpp>
 #include <hpx/components/get_ptr.hpp>
 #include <hpx/distribution_policies/container_distribution_policy.hpp>
@@ -73,6 +72,7 @@ namespace hpx {
 
         std::uint32_t this_locality = get_locality_id();
         std::vector<future<void>> ptrs;
+        ptrs.reserve(partitions_.size());
 
         typedef typename partitions_vector_type::const_iterator const_iterator;
 
@@ -346,6 +346,7 @@ namespace hpx {
         // now initialize our data structures
         std::uint32_t this_locality = get_locality_id();
         std::vector<future<void>> ptrs;
+        ptrs.reserve(num_parts);
 
         std::size_t num_part = 0;
         std::size_t allocated_size = 0;
@@ -397,7 +398,7 @@ namespace hpx {
         }
         HPX_ASSERT(l == num_parts);
 
-        hpx::when_all(ptrs).get();
+        hpx::wait_all(ptrs);
 
         // cache our partition size
         partition_size_ = get_partition_size();
@@ -440,11 +441,12 @@ namespace hpx {
 
         std::uint32_t this_locality = get_locality_id();
         std::vector<future<void>> ptrs;
+        ptrs.reserve(rhs.partitions_.size());
 
-        partitions_vector_type partitions;
         // Fixing the size of partitions to avoid race conditions between
         // possible reallocations during push back and the continuation
         // to set the local partition data
+        partitions_vector_type partitions;
         partitions.resize(rhs.partitions_.size());
         for (std::size_t i = 0; i != rhs.partitions_.size(); ++i)
         {
@@ -461,7 +463,7 @@ namespace hpx {
             }
         }
 
-        hpx::when_all(ptrs).get();
+        hpx::wait_all(ptrs);
 
         size_ = rhs.size_;
         partition_size_ = rhs.partition_size_;

components/containers/partitioned_vector/include/hpx/components/containers/partitioned_vector/partitioned_vector_segmented_iterator.hpp

@@ -1,5 +1,5 @@
 //  Copyright (c) 2014 Anuj R. Sharma
-//  Copyright (c) 2014-2016 Hartmut Kaiser
+//  Copyright (c) 2014-2022 Hartmut Kaiser
 //
 //  SPDX-License-Identifier: BSL-1.0
 //  Distributed under the Boost Software License, Version 1.0. (See accompanying

examples/throttle/spin.cpp

@@ -47,7 +47,8 @@ int hpx_main()
 
                 for (id_type const& locality_ : localities)
                 {
-                    address addr = hpx::agas::resolve(locality_).get();
+                    address addr =
+                        hpx::agas::resolve(hpx::launch::sync, locality_);
 
                     hpx::util::format_to(std::cout, "  [{1}] {2}\n",
                         get_locality_id_from_gid(locality_.get_gid()),

libs/core/futures/CMakeLists.txt

@@ -11,6 +11,7 @@ set(futures_headers
     hpx/futures/future.hpp
     hpx/futures/future_fwd.hpp
     hpx/futures/futures_factory.hpp
+    hpx/futures/future_or_value.hpp
     hpx/futures/detail/future_data.hpp
     hpx/futures/detail/future_transforms.hpp
     hpx/futures/packaged_continuation.hpp

libs/core/futures/include/hpx/futures/future_or_value.hpp

@@ -0,0 +1,71 @@
+//  Copyright (c) 2022 Hartmut Kaiser
+//
+//  SPDX-License-Identifier: BSL-1.0
+//  Distributed under the Boost Software License, Version 1.0. (See accompanying
+//  file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+
+#pragma once
+
+#include <hpx/config.hpp>
+#include <hpx/datastructures/variant.hpp>
+#include <hpx/futures/future.hpp>
+
+namespace hpx {
+
+    template <typename T>
+    struct future_or_value
+    {
+        future_or_value(T const& value)
+          : data(value)
+        {
+        }
+
+        future_or_value(T&& value) noexcept
+          : data(HPX_MOVE(value))
+        {
+        }
+
+        future_or_value(hpx::future<T>&& value) noexcept
+          : data(HPX_MOVE(value))
+        {
+        }
+
+        constexpr bool has_value() const noexcept
+        {
+            return hpx::holds_alternative<T>(data);
+        }
+        constexpr bool has_future() const noexcept
+        {
+            return hpx::holds_alternative<hpx::future<T>>(data);
+        }
+
+        T& get_value() &
+        {
+            return hpx::get<T>(data);
+        }
+        T const& get_value() const&
+        {
+            return hpx::get<T>(data);
+        }
+        T&& get_value() &&
+        {
+            return hpx::get<T>(HPX_MOVE(data));
+        }
+
+        hpx::future<T>& get_future() &
+        {
+            return hpx::get<hpx::future<T>>(data);
+        }
+        hpx::future<T> const& get_future() const&
+        {
+            return hpx::get<hpx::future<T>>(data);
+        }
+        hpx::future<T>&& get_future() &&
+        {
+            return hpx::get<hpx::future<T>>(HPX_MOVE(data));
+        }
+
+    private:
+        hpx::variant<T, hpx::future<T>> data;
+    };
+}    // namespace hpx

libs/core/lcos_local/include/hpx/lcos_local/detail/preprocess_future.hpp

@@ -123,6 +123,16 @@ namespace hpx::serialization::detail {
             ++num_futures_;
         }
 
+        void decrement_future_count()
+        {
+            std::lock_guard<mutex_type> l(mtx_);
+            HPX_ASSERT(num_futures_ > 0);
+            if (--num_futures_ == 0)
+            {
+                done_ = true;
+            }
+        }
+
         void reset()
         {
             std::lock_guard<mutex_type> l(mtx_);

libs/full/agas/include/hpx/agas/addressing_service.hpp

@@ -18,6 +18,7 @@
 #include <hpx/functional/function.hpp>
 #include <hpx/modules/agas_base.hpp>
 #include <hpx/modules/errors.hpp>
+#include <hpx/modules/futures.hpp>
 #include <hpx/modules/runtime_configuration.hpp>
 #include <hpx/naming_base/address.hpp>
 #include <hpx/naming_base/id_type.hpp>
@@ -177,7 +178,7 @@ namespace hpx { namespace agas {
         void garbage_collect(error_code& ec = throws);
 
         static std::int64_t synchronize_with_async_incref(
-            hpx::future<std::int64_t> fut, hpx::id_type const& id,
+            std::int64_t old_credit, hpx::id_type const& id,
             std::int64_t compensated_credit);
 
         server::primary_namespace& get_local_primary_namespace_service()
@@ -221,7 +222,7 @@ namespace hpx { namespace agas {
             util::runtime_configuration& rtcfg);
 
         naming::address resolve_full_postproc(naming::gid_type const& id,
-            future<primary_namespace::resolved_type> f);
+            primary_namespace::resolved_type const&);
         bool bind_postproc(
             naming::gid_type const& id, gva const& g, future<bool> f);
 
@@ -856,15 +857,17 @@ namespace hpx { namespace agas {
         }
 
         ///////////////////////////////////////////////////////////////////////////
-        hpx::future<naming::address> resolve_async(naming::gid_type const& id);
+        hpx::future_or_value<naming::address> resolve_async(
+            naming::gid_type const& id);
 
-        hpx::future<naming::address> resolve_async(hpx::id_type const& id)
+        hpx::future_or_value<naming::address> resolve_async(
+            hpx::id_type const& id)
         {
             return resolve_async(id.get_gid());
         }
 
         ///////////////////////////////////////////////////////////////////////////
-        hpx::future<hpx::id_type> get_colocation_id_async(
+        hpx::future_or_value<id_type> get_colocation_id_async(
             hpx::id_type const& id);
 
         ///////////////////////////////////////////////////////////////////////////
@@ -893,10 +896,11 @@ namespace hpx { namespace agas {
             return addr;
         }
 
-        hpx::future<naming::address> resolve_full_async(
+        hpx::future_or_value<naming::address> resolve_full_async(
             naming::gid_type const& id);
 
-        hpx::future<naming::address> resolve_full_async(hpx::id_type const& id)
+        hpx::future_or_value<naming::address> resolve_full_async(
+            hpx::id_type const& id)
         {
             return resolve_full_async(id.get_gid());
         }
@@ -978,14 +982,25 @@ namespace hpx { namespace agas {
         ///                   throw but returns the result code using the
         ///                   parameter \a ec. Otherwise it throws an instance
         ///                   of hpx#exception.
-        hpx::future<std::int64_t> incref_async(naming::gid_type const& gid,
+        hpx::future_or_value<std::int64_t> incref_async(
+            naming::gid_type const& gid, std::int64_t credits = 1,
+            hpx::id_type const& keep_alive = hpx::invalid_id);
+
+        ///  \cond NOINTERN
+        std::int64_t incref_async_helper(naming::gid_type const& gid,
             std::int64_t credits = 1,
             hpx::id_type const& keep_alive = hpx::invalid_id);
+        /// \endcond
 
         std::int64_t incref(naming::gid_type const& gid,
             std::int64_t credits = 1, error_code& ec = throws)
         {
-            return incref_async(gid, credits).get(ec);
+            auto result = incref_async(gid, credits);
+            if (result.has_value())
+            {
+                return HPX_MOVE(result).get_value();
+            }
+            return result.get_future().get(ec);
         }
 
         /// \brief Decrement the global reference count for the given id