Use std::map for Place <--> DeviceContext

paddle/fluid/framework/details/op_handle_base.cc

@@ -124,16 +124,10 @@ void OpHandleBase::RunAndRecordEvent(const std::function<void()> &callback) {
 #ifdef PADDLE_WITH_CUDA
   if (!events_.empty()) {  // Use event
     std::function<void()> method = callback;
-    // NOTE(zcd): device context must be ordered here because RecordEvent
-    // will use a mutex to ensure the safe of multi-threads.
-    std::map<platform::DeviceContext *, platform::Place> ordered_ctxes;
     for (auto &p : dev_ctxes_) {
-      ordered_ctxes.emplace(p.second, p.first);
-    }
-    for (auto &p : ordered_ctxes) {
       method = [method, p, this]() {
-        static_cast<platform::CUDADeviceContext *>(p.first)->RecordEvent(
-            events_.at(boost::get<platform::CUDAPlace>(p.second).device),
+        static_cast<platform::CUDADeviceContext *>(p.second)->RecordEvent(
+            events_.at(boost::get<platform::CUDAPlace>(p.first).device),
             method);
       };
     }

paddle/fluid/framework/details/op_handle_base.h

@@ -13,9 +13,9 @@
 // limitations under the License.
 
 #pragma once
+#include <map>
 #include <string>
 #include <vector>
-
 #include "paddle/fluid/framework/details/var_handle.h"
 #include "paddle/fluid/platform/device_context.h"
 #include "paddle/fluid/platform/macros.h"
@@ -92,9 +92,7 @@ class OpHandleBase {
 
   std::vector<VarHandleBase *> inputs_;
   std::vector<VarHandleBase *> outputs_;
-  std::unordered_map<platform::Place, platform::DeviceContext *,
-                     platform::PlaceHash>
-      dev_ctxes_;
+  std::map<platform::Place, platform::DeviceContext *> dev_ctxes_;
 
 #ifdef PADDLE_WITH_CUDA
   std::unordered_map<int, cudaEvent_t> events_;

paddle/fluid/framework/details/reduce_and_gather.h

@@ -54,8 +54,7 @@ struct ReduceLoDTensor {
 inline void GatherSelectedRows(
     const std::vector<const SelectedRows *> &src_selecte_rows_,
     const std::vector<platform::Place> &in_places,
-    const std::unordered_map<platform::Place, platform::DeviceContext *,
-                             platform::PlaceHash> &dev_ctxes,
+    const std::map<platform::Place, platform::DeviceContext *> &dev_ctxes,
     const platform::Place &out_place, SelectedRows *dst_selecte_rows) {
   PADDLE_ENFORCE(!src_selecte_rows_.empty());
 

paddle/fluid/platform/device_context.cc

@@ -10,6 +10,7 @@ See the License for the specific language governing permissions and
 limitations under the License. */
 #include "paddle/fluid/platform/device_context.h"
 
+#include <set>
 #include <string>
 #include <unordered_set>
 #include <vector>
@@ -35,7 +36,7 @@ DeviceContextPool::DeviceContextPool(
     const std::vector<platform::Place>& places) {
   PADDLE_ENFORCE_GT(places.size(), 0);
   using PtrType = std::unique_ptr<DeviceContext>;
-  std::unordered_set<Place, PlaceHash> set;
+  std::set<Place> set;
   for (auto& p : places) {
     set.insert(p);
   }

paddle/fluid/platform/device_context.h

@@ -27,12 +27,12 @@ limitations under the License. */
 #include <mkldnn.hpp>
 #endif
 
+#include <map>
+#include "glog/logging.h"
 #include "paddle/fluid/platform/enforce.h"
 #include "paddle/fluid/platform/place.h"
 #include "unsupported/Eigen/CXX11/Tensor"
 
-#include "glog/logging.h"
-
 namespace paddle {
 namespace platform {
 
@@ -201,9 +201,7 @@ class DeviceContextPool {
 
  private:
   static DeviceContextPool* pool;
-  std::unordered_map<const platform::Place,
-                     std::unique_ptr<platform::DeviceContext>, PlaceHash>
-      device_contexts_;
+  std::map<Place, std::unique_ptr<DeviceContext>> device_contexts_;
   DISABLE_COPY_AND_ASSIGN(DeviceContextPool);
 };
 

paddle/fluid/platform/place.h

@@ -30,6 +30,7 @@ struct CPUPlace {
   // needed for variant equality comparison
   inline bool operator==(const CPUPlace &) const { return true; }
   inline bool operator!=(const CPUPlace &) const { return false; }
+  inline bool operator<(const CPUPlace &) const { return false; }
 };
 
 struct CUDAPlace {
@@ -42,6 +43,7 @@ struct CUDAPlace {
     return device == o.device;
   }
   inline bool operator!=(const CUDAPlace &o) const { return !(*this == o); }
+  inline bool operator<(const CUDAPlace &o) const { return device < o.device; }
 
   int device;
 };
@@ -52,6 +54,7 @@ struct CUDAPinnedPlace {
   // needed for variant equality comparison
   inline bool operator==(const CUDAPinnedPlace &) const { return true; }
   inline bool operator!=(const CUDAPinnedPlace &) const { return false; }
+  inline bool operator<(const CUDAPinnedPlace &) const { return false; }
 };
 
 struct IsCUDAPlace : public boost::static_visitor<bool> {
@@ -89,18 +92,6 @@ bool is_cuda_pinned_place(const Place &);
 bool places_are_same_class(const Place &, const Place &);
 bool is_same_place(const Place &, const Place &);
 
-struct PlaceHash {
-  std::size_t operator()(const Place &p) const {
-    constexpr size_t num_dev_bits = 4;
-    std::hash<int> ihash;
-    size_t dev_id = 0;
-    if (is_gpu_place(p)) {
-      dev_id = boost::get<CUDAPlace>(p).device;
-    }
-    return ihash(dev_id << num_dev_bits | p.which());
-  }
-};
-
 std::ostream &operator<<(std::ostream &, const Place &);
 
 template <typename Visitor>