OF_ONCE_GUARD

oneflow/core/comm_network/comm_network.h

@@ -23,7 +23,13 @@ class CommNetwork {
   virtual void SendActorMsg(int64_t dst_machine_id, const ActorMsg& msg) = 0;
   virtual void SetCallbackForReceivedActorMsg(
       std::function<void(const ActorMsg&)> callback) = 0;
-  virtual void Barrier(const std::string& barrier_name) = 0;
+
+  //
+  void Barrier(const std::string& barrier_name) {}
+  bool TryLock(const std::string& name) {
+    return true;  // TODO
+  }
+  void UnLock(const std::string& name) {}
 
  protected:
   CommNetwork() = default;
@@ -35,10 +41,17 @@ class CommNetwork {
   static CommNetwork* comm_network_ptr_;
 };
 
-#define OF_MACRO_TRICK1(x) #x
-#define OF_MACRO_TRICK2(x) OF_MACRO_TRICK1(x)
-#define OF_BARRIER() \
-  CommNetwork::Singleton()->Barrier(__FILE__ ":" OF_MACRO_TRICK2(__LINE__))
+#define FILE_LINE_STR __FILE__ ":" OF_PP_STRINGIZE(__LINE__)
+
+#define OF_BARRIER() CommNetwork::Singleton()->Barrier(FILE_LINE_STR)
+
+#define OF_ONCE_GUARD(...)                                           \
+  do {                                                               \
+    bool locked = CommNetwork::Singleton()->TryLock(FILE_LINE_STR);  \
+    if (locked) { __VA_ARGS__; }                                     \
+    CommNetwork::Singleton()->Barrier(FILE_LINE_STR);                \
+    if (locked) { CommNetwork::Singleton()->UnLock(FILE_LINE_STR); } \
+  } while (0)
 
 }  // namespace oneflow
 

oneflow/core/comm_network/rdma_comm_network.h

@@ -33,9 +33,6 @@ class RdmaCommNetwork final : public CommNetwork {
       std::function<void(const ActorMsg&)> callback) override {
     // TODO
   }
-  void Barrier(const std::string& barrier_name) override {
-    // TODO
-  }
 
  private:
   RdmaCommNetwork() = default;

oneflow/core/persistence/file_system.cpp

@@ -13,12 +13,7 @@ OF_DEFINE_ENUM_TO_OSTREAM_FUNC(Status);
 
 void FileSystem::CreateDirIfNotExist(const std::string& dirname) {
   if (IsDirectory(dirname) == Status::OK) { return; }
-  Status st = CreateDir(dirname);
-  if (st == Status::ALREADY_EXISTS) {
-    FS_CHECK_OK(IsDirectory(dirname));
-  } else {
-    FS_CHECK_OK(st);
-  }
+  FS_CHECK_OK(CreateDir(dirname));
 }
 
 std::string FileSystem::TranslateName(const std::string& name) const {

oneflow/core/persistence/snapshot.h

 #ifndef ONEFLOW_CORE_PERSISTENCE_SNAPSHOT_H_
 #define ONEFLOW_CORE_PERSISTENCE_SNAPSHOT_H_
 
+#include "oneflow/core/comm_network/comm_network.h"
 #include "oneflow/core/persistence/normal_persistent_in_stream.h"
 #include "oneflow/core/persistence/persistent_out_stream.h"
 

oneflow/core/persistence/snapshot_manager.cpp

@@ -7,7 +7,7 @@ namespace oneflow {
 void SnapshotMgr::Init() {
   LOG(INFO) << "SnapshotMgr Init";
   model_save_snapshots_path_ = JobDesc::Singleton()->md_save_snapshots_path();
-  GlobalFS()->CreateDirIfNotExist(model_save_snapshots_path_);
+  OF_ONCE_GUARD(GlobalFS()->CreateDirIfNotExist(model_save_snapshots_path_));
   std::vector<std::string> result;
   FS_CHECK_OK(GlobalFS()->GetChildren(model_save_snapshots_path_, &result));
   CHECK_EQ(result.size(), 0);