Add proper unique_ids for tasks.

NOTES.md

@@ -4,6 +4,31 @@ A collection of stuff that we noticed during development.
 Useful later on two write a project report and to go back
 in time to find out why certain decisions where made.
 
+## 12.04.2019 - Unique IDs
+
+Assigning unique IDs to logical different tasks is key to the
+current model of separating timing/memory guarantees for certain
+parallel patterns.
+
+We do want to assign these IDs automatic in most cases (a call to
+some parallel API should not require the end user to specific a
+unique ID for each different call, as this would be error prone).
+Instead we want to make sure that each DIFFERENT API call is separated
+automatic, while leaving the option for manual ID assignment for later
+implementations of GPU offloading (tasks need to have identifiers for
+this to work properly).
+
+Our first approach was using the `__COUNTER__` macro,
+but this only works in ONE COMPLIATION UNIT and is not
+portable to all compilers.
+
+As all our unique instances are copled to a class/type
+we decided to implement the unique IDs using
+typeid(tuple<T..>) in automatic cases (bound to a specific type)
+and fully manual IDs in other types. All this is wrapped in a
+helper::unique_id class.
+
+
 ## 11.04.2019 - Lambda Pointer Abstraction
 
 The question is if we could use a pointer to a lambda without

app/playground/CMakeLists.txt

 add_executable(playground main.cpp)
 
 # Example for adding the library to your app (as a cmake project dependency)
-target_link_libraries(playground  pls)
\ No newline at end of file
+target_link_libraries(playground  pls)

app/playground/main.cpp

@@ -4,16 +4,14 @@
 #include <array>
 #include <atomic>
 #include <memory>
+#include <typeindex>
+#include <tuple>
 
-#include <pls/pls.h>
-#include <pls/internal/helpers/prohibit_new.h>
-#include <pls/internal/scheduling/thread_state.h>
+#include <pls/internal/scheduling/root_task.h>
+#include <pls/internal/helpers/unique_id.h>
 
-using namespace pls;
 
 int main() {
-    malloc_scheduler_memory sched_memory{8};
-    std::cout << (std::uintptr_t)sched_memory.thread_for(0) % 64 << ", " << (std::uintptr_t)sched_memory.thread_for(1) % 64 << ", " << (std::uintptr_t)sched_memory.thread_for(2) % 64 << ", " << std::endl;
-    std::cout << (std::uintptr_t)sched_memory.thread_state_for(0) % 64 << ", " << (std::uintptr_t)sched_memory.thread_state_for(1) % 64 << ", " << (std::uintptr_t)sched_memory.thread_state_for(2) % 64 << ", " << std::endl;
-    std::cout << (std::uintptr_t)sched_memory.task_stack_for(0) % 64 << ", " << (std::uintptr_t)sched_memory.task_stack_for(1) % 64 << ", " << (std::uintptr_t)sched_memory.task_stack_for(2) % 64 << ", " << std::endl;
+    std::cout << pls::internal::scheduling::root_task<void(*)>::create_id().type_.hash_code() << std::endl;
+    std::cout << pls::internal::helpers::unique_id::create<pls::internal::scheduling::root_task<void(*)>>().type_.hash_code() << std::endl;
 }

lib/pls/CMakeLists.txt

@@ -29,7 +29,7 @@ add_library(pls STATIC
         include/pls/internal/scheduling/run_on_n_threads_task.h src/internal/scheduling/run_on_n_threads_task.cpp
         include/pls/internal/scheduling/fork_join_task.h        src/internal/scheduling/fork_join_task.cpp
         include/pls/internal/scheduling/scheduler_memory.h      src/internal/scheduling/scheduler_memory.cpp
-)
+        include/pls/internal/helpers/unique_id.h)
 
 # Add everything in `./include` to be in the include path of this project
 target_include_directories(pls

lib/pls/include/pls/algorithms/invoke_parallel_impl.h

@@ -4,6 +4,7 @@
 
 #include "pls/internal/scheduling/fork_join_task.h"
 #include "pls/internal/scheduling/scheduler.h"
+#include "pls/internal/helpers/unique_id.h"
 
 namespace pls {
     namespace algorithm {
@@ -29,7 +30,8 @@ namespace pls {
         template<typename Function1, typename Function2>
         void invoke_parallel(const Function1& function1, const Function2& function2) {
             using namespace ::pls::internal::scheduling;
-            static abstract_task::id id{PLS_UNIQUE_ID, true};
+            using namespace ::pls::internal::helpers;
+            static abstract_task::id id = unique_id::create<Function1, Function2>();
 
             auto internal_body = [&] (fork_join_sub_task* this_task){
                 auto sub_task_body_1 = [&] (fork_join_sub_task*){ function1(); };
@@ -46,7 +48,8 @@ namespace pls {
         template<typename Function1, typename Function2, typename Function3>
         void invoke_parallel(const Function1& function1, const Function2& function2, const Function3& function3) {
             using namespace ::pls::internal::scheduling;
-            static abstract_task::id id{PLS_UNIQUE_ID, true};
+            using namespace ::pls::internal::helpers;
+            static abstract_task::id id = unique_id::create<Function1, Function2, Function3>();
 
             auto internal_body = [&] (fork_join_sub_task* this_task){
                 auto sub_task_body_1 = [&] (fork_join_sub_task*){ function1(); };

lib/pls/include/pls/internal/helpers/unique_id.h

+
+#ifndef PLS_UNIQUE_ID_H
+#define PLS_UNIQUE_ID_H
+
+#include <typeindex>
+#include <tuple>
+#include <stdint.h>
+
+namespace pls {
+    namespace internal {
+        namespace helpers {
+            struct unique_id {
+                const uint32_t id_;
+                const std::type_info& type_;
+                bool operator==(const unique_id& other) const { return id_ == other.id_ && type_ == other.type_; }
+
+                static constexpr unique_id create(const uint32_t id) {
+                    return unique_id(id, typeid(void));
+                }
+                template<typename ...T>
+                static constexpr unique_id create() {
+                    return unique_id(UINT32_MAX, typeid(std::tuple<T...>));
+                }
+            private:
+                explicit constexpr unique_id(const uint32_t id, const std::type_info& type): id_{id}, type_{type} {};
+            };
+        }
+    }
+}
+
+#endif //PLS_UNIQUE_ID_H

lib/pls/include/pls/internal/scheduling/abstract_task.h

@@ -2,25 +2,15 @@
 #ifndef PLS_ABSTRACT_TASK_H
 #define PLS_ABSTRACT_TASK_H
 
-#define PLS_UNIQUE_ID __COUNTER__
-
 #include "pls/internal/base/spin_lock.h"
+#include "pls/internal/helpers/unique_id.h"
 
 namespace pls {
     namespace internal {
         namespace scheduling {
             class abstract_task {
             public:
-                struct id {
-                    uint32_t id_;
-                    bool auto_generated_;
-
-                    explicit id(uint32_t id, bool auto_generated=false): id_{id}, auto_generated_{auto_generated} {};
-
-                    bool operator==(const abstract_task::id& other) const {
-                        return id_ == other.id_ && auto_generated_ == other.auto_generated_;
-                    }
-                };
+                using id = helpers::unique_id;
 
             private:
                 int depth_;

lib/pls/include/pls/internal/scheduling/root_task.h

@@ -17,12 +17,14 @@ namespace pls {
                 Function function_;
                 std::atomic_uint8_t finished_;
             public:
+                static constexpr auto create_id = helpers::unique_id::create<root_task<Function>>;
+
                 explicit root_task(Function function):
-                    abstract_task{0, id{0}},
+                    abstract_task{0, create_id()},
                     function_{function},
                     finished_{0} {}
                 root_task(const root_task& other):
-                    abstract_task{0, id{0}},
+                    abstract_task{0, create_id()},
                     function_{other.function_},
                     finished_{0} {}
 
@@ -50,8 +52,10 @@ namespace pls {
                 root_task<Function>* master_task_;
 
             public:
+                static constexpr auto create_id = root_task<Function>::create_id;
+
                 explicit root_worker_task(root_task<Function>* master_task):
-                        abstract_task{0, id{0}},
+                        abstract_task{0, create_id()},
                         master_task_{master_task} {}
 
                 void execute() override {

lib/pls/include/pls/internal/scheduling/run_on_n_threads_task.h

@@ -36,8 +36,10 @@ namespace pls {
                     return counter;
                 }
             public:
+                static constexpr auto create_id = helpers::unique_id::create<run_on_n_threads_task<Function>>;
+
                 run_on_n_threads_task(Function function, int num_threads):
-                    abstract_task{0, id{PLS_UNIQUE_ID, true}},
+                    abstract_task{0, create_id()},
                     function_{function},
                     counter{num_threads - 1} {}
 
@@ -65,8 +67,10 @@ namespace pls {
                 Function function_;
                 run_on_n_threads_task<Function>* root_;
             public:
+                static constexpr auto create_id = helpers::unique_id::create<run_on_n_threads_task_worker<Function>>;
+
                 run_on_n_threads_task_worker(Function function, run_on_n_threads_task<Function>* root):
-                        abstract_task{0, id{PLS_UNIQUE_ID, true}},
+                        abstract_task{0, create_id()},
                         function_{function},
                         root_{root} {}
 

lib/pls/include/pls/pls.h

@@ -5,6 +5,7 @@
 #include "pls/internal/scheduling/abstract_task.h"
 #include "pls/internal/scheduling/fork_join_task.h"
 #include "pls/internal/scheduling/scheduler.h"
+#include "pls/internal/helpers/unique_id.h"
 
 namespace pls {
     using internal::scheduling::static_scheduler_memory;
@@ -13,6 +14,8 @@ namespace pls {
     using internal::scheduling::scheduler;
     using task_id = internal::scheduling::abstract_task::id;
 
+    using unique_id = internal::helpers::unique_id;
+
     using internal::scheduling::fork_join_sub_task;
     using internal::scheduling::fork_join_task;
 

test/scheduling_tests.cpp

@@ -58,7 +58,7 @@ TEST_CASE( "tbb task are scheduled correctly", "[internal/scheduling/fork_join_t
 
         my_scheduler.perform_work([&] (){
             once_sub_task sub_task{&counter, start_counter};
-            fork_join_task task{&sub_task, task_id{42}};
+            fork_join_task task{&sub_task, unique_id::create(42)};
             scheduler::execute_task(task);
         });
 
@@ -71,7 +71,7 @@ TEST_CASE( "tbb task are scheduled correctly", "[internal/scheduling/fork_join_t
         my_scheduler.perform_work([&] (){
             std::atomic<int> dummy_parent{1}, overall_counter{8};
             force_steal_sub_task sub_task{&dummy_parent, &overall_counter};
-            fork_join_task task{&sub_task, task_id{42}};
+            fork_join_task task{&sub_task, unique_id::create(42)};
             scheduler::execute_task(task);
         });
         my_scheduler.terminate(true);