dataflow_cpp: sources need to return false if processing should be stopped

049b3b00 · Marcus Winter · b7744ae6 · 049b3b00 · 049b3b00 · 049b3b00
Commit 049b3b00 authored Oct 14, 2014 by Marcus Winter
10 changed files
--- a/dataflow_cpp/include/embb/dataflow/internal/constant_source.h
+++ b/dataflow_cpp/include/embb/dataflow/internal/constant_source.h
@@ -56,8 +56,9 @@ class ConstantSource
    GetOutput<0>().Send(Signal<Type>(clock, value_));
  }
-  virtual void Start(int clock) {
+  virtual bool Start(int clock) {
    Run(clock);
+    return true;
  }
  OutputsType & GetOutputs() {

--- a/dataflow_cpp/include/embb/dataflow/internal/node.h
+++ b/dataflow_cpp/include/embb/dataflow/internal/node.h
@@ -42,7 +42,7 @@ class Node {
  virtual bool HasInputs() const { return false; }
  virtual bool HasOutputs() const { return false; }
  virtual void Run(int clock) = 0;
-  virtual void Start(int /*clock*/) {
+  virtual bool Start(int /*clock*/) {
    EMBB_THROW(embb::base::ErrorException,
      "Nodes are started implicitly.");
  }

--- a/dataflow_cpp/include/embb/dataflow/internal/source.h
+++ b/dataflow_cpp/include/embb/dataflow/internal/source.h
@@ -52,7 +52,7 @@ class Source< Slices, Outputs<Slices, O1, O2, O3, O4, O5> >
  typedef typename ExecutorType::FunctionType FunctionType;
  explicit Source(FunctionType function)
-    : executor_(function) {
+    : executor_(function), not_done_(true) {
    next_clock_ = 0;
  }
@@ -61,15 +61,18 @@ class Source< Slices, Outputs<Slices, O1, O2, O3, O4, O5> >
  }
  virtual void Run(int clock) {
-    executor_.Execute(clock, outputs_);
+    not_done_ = executor_.Execute(clock, outputs_);
    next_clock_++;
  }
-  virtual void Start(int clock) {
+  virtual bool Start(int clock) {
    while (clock != next_clock_) embb::base::Thread::CurrentYield();
-    const int idx = clock % Slices;
+    if (not_done_) {
-    action_[idx] = Action(this, clock);
+      const int idx = clock % Slices;
-    sched_->Spawn(action_[idx]);
+      action_[idx] = Action(this, clock);
+      sched_->Spawn(action_[idx]);
+    }
+    return not_done_;
  }
  OutputsType & GetOutputs() {
@@ -90,6 +93,7 @@ class Source< Slices, Outputs<Slices, O1, O2, O3, O4, O5> >
  OutputsType outputs_;
  ExecutorType executor_;
  Action action_[Slices];
+  volatile bool not_done_;
  embb::base::Atomic<int> next_clock_;
 };

--- a/dataflow_cpp/include/embb/dataflow/internal/source_executor.h
+++ b/dataflow_cpp/include/embb/dataflow/internal/source_executor.h
@@ -42,16 +42,17 @@ class SourceExecutor;
 template <int Slices, typename O1>
 class SourceExecutor< Outputs<Slices, O1> > {
 public:
-  typedef embb::base::Function<void, O1 &> FunctionType;
+  typedef embb::base::Function<bool, O1 &> FunctionType;
  explicit SourceExecutor(FunctionType func) : function_(func) {}
-  void Execute(
+  bool Execute(
    int clock,
    Outputs<Slices, O1> & outputs) {
    O1 o1;
-    function_(o1);
+    bool result = function_(o1);
    outputs.template Get<0>().Send(Signal<O1>(clock, o1));
+    return result;
  }
 private:
@@ -61,18 +62,19 @@ class SourceExecutor< Outputs<Slices, O1> > {
 template <int Slices, typename O1, typename O2>
 class SourceExecutor< Outputs<Slices, O1, O2> > {
 public:
-  typedef embb::base::Function<void, O1 &, O2 &> FunctionType;
+  typedef embb::base::Function<bool, O1 &, O2 &> FunctionType;
  explicit SourceExecutor(FunctionType func) : function_(func) {}
-  void Execute(
+  bool Execute(
    int clock,
    Outputs<Slices, O1, O2> & outputs) {
    O1 o1;
    O2 o2;
-    function_(o1, o2);
+    bool result = function_(o1, o2);
    outputs.template Get<0>().Send(Signal<O1>(clock, o1));
    outputs.template Get<1>().Send(Signal<O2>(clock, o2));
+    return result;
  }
 private:
@@ -82,20 +84,21 @@ class SourceExecutor< Outputs<Slices, O1, O2> > {
 template <int Slices, typename O1, typename O2, typename O3>
 class SourceExecutor< Outputs<Slices, O1, O2, O3> > {
 public:
-  typedef embb::base::Function<void, O1 &, O2 &, O3 &> FunctionType;
+  typedef embb::base::Function<bool, O1 &, O2 &, O3 &> FunctionType;
  explicit SourceExecutor(FunctionType func) : function_(func) {}
-  void Execute(
+  bool Execute(
    int clock,
    Outputs<Slices, O1, O2, O3> & outputs) {
    O1 o1;
    O2 o2;
    O3 o3;
-    function_(o1, o2, o3);
+    bool result = function_(o1, o2, o3);
    outputs.template Get<0>().Send(Signal<O1>(clock, o1));
    outputs.template Get<1>().Send(Signal<O2>(clock, o2));
    outputs.template Get<2>().Send(Signal<O3>(clock, o3));
+    return result;
  }
 private:
@@ -105,22 +108,23 @@ class SourceExecutor< Outputs<Slices, O1, O2, O3> > {
 template <int Slices, typename O1, typename O2, typename O3, typename O4>
 class SourceExecutor< Outputs<Slices, O1, O2, O3, O4> > {
 public:
-  typedef embb::base::Function<void, O1 &, O2 &, O3 &, O4 &> FunctionType;
+  typedef embb::base::Function<bool, O1 &, O2 &, O3 &, O4 &> FunctionType;
  explicit SourceExecutor(FunctionType func) : function_(func) {}
-  void Execute(
+  bool Execute(
    int clock,
    Outputs<Slices, O1, O2, O3, O4> & outputs) {
    O1 o1;
    O2 o2;
    O3 o3;
    O4 o4;
-    function_(o1, o2, o3, o4);
+    bool result = function_(o1, o2, o3, o4);
    outputs.template Get<0>().Send(Signal<O1>(clock, o1));
    outputs.template Get<1>().Send(Signal<O2>(clock, o2));
    outputs.template Get<2>().Send(Signal<O3>(clock, o3));
    outputs.template Get<3>().Send(Signal<O4>(clock, o4));
+    return result;
  }
 private:
@@ -131,11 +135,11 @@ template <int Slices, typename O1, typename O2, typename O3, typename O4,
  typename O5>
 class SourceExecutor< Outputs<Slices, O1, O2, O3, O4, O5> > {
 public:
-  typedef embb::base::Function<void, O1 &, O2 &, O3 &, O4 &, O5 &> FunctionType;
+  typedef embb::base::Function<bool, O1 &, O2 &, O3 &, O4 &, O5 &> FunctionType;
  explicit SourceExecutor(FunctionType func) : function_(func) {}
-  void Execute(
+  bool Execute(
    int clock,
    Outputs<Slices, O1, O2, O3, O4, O5> & outputs) {
    O1 o1;
@@ -143,12 +147,13 @@ class SourceExecutor< Outputs<Slices, O1, O2, O3, O4, O5> > {
    O3 o3;
    O4 o4;
    O5 o5;
-    function_(o1, o2, o3, o4, o5);
+    bool result = function_(o1, o2, o3, o4, o5);
    outputs.template Get<0>().Send(Signal<O1>(clock, o1));
    outputs.template Get<1>().Send(Signal<O2>(clock, o2));
    outputs.template Get<2>().Send(Signal<O3>(clock, o3));
    outputs.template Get<3>().Send(Signal<O4>(clock, o4));
    outputs.template Get<4>().Send(Signal<O5>(clock, o5));
+    return result;
  }
 private:

--- a/dataflow_cpp/include/embb/dataflow/network.h
+++ b/dataflow_cpp/include/embb/dataflow/network.h
@@ -697,10 +697,9 @@ class Network {
  void Add(ConstantSource<Type> & source);
  /**
-   * Executes the network for at most \c elements tokens.
+   * Executes the network until one of the the sources returns \c false.
-   * \param elements Maximum number of tokens to process.
   */
-  void operator () (int elements);
+  void operator () ();
 };
 #else
@@ -862,7 +861,7 @@ class Network : public internal::ClockListener {
    sources_.push_back(&source);
  }
-  void operator () (int elements) {
+  void operator () () {
    internal::SchedulerSequential sched_seq;
    internal::SchedulerMTAPI<Slices> sched_mtapi;
    internal::Scheduler * sched = &sched_mtapi;
@@ -876,16 +875,22 @@ class Network : public internal::ClockListener {
    for (int ii = 0; ii < Slices; ii++) sink_count_[ii] = 0;
-    for (int clock = 0; clock < elements; clock++) {
+    int clock = 0;
+    while (clock >= 0) {
      const int idx = clock % Slices;
      while (sink_count_[idx] > 0) embb::base::Thread::CurrentYield();
      sched->WaitForSlice(idx);
-      SpawnClock(clock);
+      if (!SpawnClock(clock))
+        break;
+      clock++;
    }
-    for (int ii = 0; ii < Slices; ii++) {
+    int ii = clock - Slices + 1;
-      while (sink_count_[ii] > 0) embb::base::Thread::CurrentYield();
+    if (ii < 0) ii = 0;
-      sched->WaitForSlice(ii);
+    for (; ii < clock; ii++) {
+      const int idx = ii % Slices;
+      while (sink_count_[idx] > 0) embb::base::Thread::CurrentYield();
+      sched->WaitForSlice(idx);
    }
  }
@@ -912,15 +917,17 @@ class Network : public internal::ClockListener {
  std::vector<int> spawn_history_[Slices];
 #endif
-  void SpawnClock(int clock) {
+  bool SpawnClock(int clock) {
    const int idx = clock % Slices;
+    bool result = true;
 #if EMBB_DATAFLOW_TRACE_SIGNAL_HISTORY
    spawn_history_[idx].push_back(clock);
 #endif
    sink_count_[idx] = static_cast<int>(sinks_.size());
    for (size_t kk = 0; kk < sources_.size(); kk++) {
-      sources_[kk]->Start(clock);
+      result &= sources_[kk]->Start(clock);
    }
+    return result;
  }
 };

--- a/dataflow_cpp/test/dataflow_cpp_test_simple.cc
+++ b/dataflow_cpp/test/dataflow_cpp_test_simple.cc
@@ -53,11 +53,13 @@ typedef MyNetwork::Select< int > MySelect;
 embb::base::Atomic<int> source_counter;
 int source_array[TEST_COUNT];
-void sourceFunc(int & out) {
+bool sourceFunc(int & out) {
  out = source_counter;
  source_array[source_counter] = out;
  source_counter++;
+  return source_counter < 12;
 }
 embb::base::Atomic<int> pred_counter;
@@ -195,7 +197,7 @@ void SimpleTest::TestBasic() {
    network.Add(sink);
-    network(TEST_COUNT);
+    network();
    PT_EXPECT(asink.Check());
  }

--- a/doc/examples/dataflow/dataflow_nonlinear-fragmented.cc
+++ b/doc/examples/dataflow/dataflow_nonlinear-fragmented.cc
@@ -65,5 +65,5 @@ void RunDataflowNonLinear() {
  process5.GetOutput<1>() >> sink1.GetInput<2>();
  process4.GetOutput<1>() >> sink1.GetInput<3>();
-  nw(10);
+  nw();
 }
--- a/doc/examples/dataflow/dataflow_producer-snippet.h
+++ b/doc/examples/dataflow/dataflow_producer-snippet.h
 template <typename T>
 class Producer {
 public:
-  explicit Producer(int seed) : seed_(seed) {}
+  explicit Producer(int seed) : seed_(seed), count_(4) {}
-  void Run(T& x) {
+  bool Run(T& x) {
    // produce a new value x
    x = SimpleRand(seed_);
+    count_--;
+    return count_ >= 0;
  }
 private:
  int seed_;
+  int count_;
 };
--- a/doc/examples/dataflow/dataflow_run-snippet.h
+++ b/doc/examples/dataflow/dataflow_run-snippet.h
-  nw(4);
+  nw();
--- a/doc/examples/dataflow/dataflow_source_function-snippet.h
+++ b/doc/examples/dataflow/dataflow_source_function-snippet.h
-void SourceFunction(std::string & str) {
+bool SourceFunction(std::string & str) {
  std::getline(file, str);
+  return !file.eof();
 }