diff --git a/paddle/fluid/distributed/fleet_executor/task_loop.cc b/paddle/fluid/distributed/fleet_executor/task_loop.cc
index 270bce7786038..44e853a0d9684 100644
--- a/paddle/fluid/distributed/fleet_executor/task_loop.cc
+++ b/paddle/fluid/distributed/fleet_executor/task_loop.cc
@@ -17,8 +17,7 @@
 #include "paddle/fluid/platform/enforce.h"
 #include "paddle/fluid/platform/errors.h"
 
-namespace paddle {
-namespace distributed {
+namespace paddle::distributed {
 
 thread_local TaskLoop* TaskLoop::thread_local_loop_ = nullptr;
 
@@ -81,5 +80,4 @@ void TaskLoop::AbortNotInLoopThread() {
       std::this_thread::get_id()));
 }
 
-}  // namespace distributed
-}  // namespace paddle
+}  // namespace paddle::distributed
diff --git a/paddle/fluid/distributed/ps/table/graph/graph_node.cc b/paddle/fluid/distributed/ps/table/graph/graph_node.cc
index 31c098c49fba2..fa8fa61a23eab 100644
--- a/paddle/fluid/distributed/ps/table/graph/graph_node.cc
+++ b/paddle/fluid/distributed/ps/table/graph/graph_node.cc
@@ -15,8 +15,7 @@
 #include "paddle/fluid/distributed/ps/table/graph/graph_node.h"
 
 #include <cstring>
-namespace paddle {
-namespace distributed {
+namespace paddle::distributed {
 
 GraphNode::~GraphNode() {
   if (sampler != nullptr) {
@@ -122,5 +121,4 @@ void FeatureNode::recover_from_buffer(char* buffer) {
     feature.push_back(str);  // NOLINT
   }
 }
-}  // namespace distributed
-}  // namespace paddle
+}  // namespace paddle::distributed
diff --git a/paddle/fluid/framework/details/all_reduce_op_handle.cc b/paddle/fluid/framework/details/all_reduce_op_handle.cc
index 4c78b12fd4ac4..5e4edb1ca2870 100644
--- a/paddle/fluid/framework/details/all_reduce_op_handle.cc
+++ b/paddle/fluid/framework/details/all_reduce_op_handle.cc
@@ -24,9 +24,7 @@
 COMMON_DECLARE_bool(sync_nccl_allreduce);
 #endif
 
-namespace paddle {
-namespace framework {
-namespace details {
+namespace paddle::framework::details {
 
 #if defined(PADDLE_WITH_NCCL) || defined(PADDLE_WITH_RCCL)
 AllReduceOpHandle::AllReduceOpHandle(ir::Node *node,
@@ -335,6 +333,4 @@ void AllReduceOpHandle::SyncNCCLAllReduce() {
 #endif
 
 std::string AllReduceOpHandle::Name() const { return "all_reduce"; }
-}  // namespace details
-}  // namespace framework
-}  // namespace paddle
+}  // namespace paddle::framework::details
diff --git a/paddle/fluid/framework/details/eager_deletion_op_handle.cc b/paddle/fluid/framework/details/eager_deletion_op_handle.cc
index 4dbff851f00e2..b8db1e321257b 100644
--- a/paddle/fluid/framework/details/eager_deletion_op_handle.cc
+++ b/paddle/fluid/framework/details/eager_deletion_op_handle.cc
@@ -21,15 +21,11 @@
 #endif
 #include <algorithm>
 
-namespace paddle {
-namespace framework {
+namespace paddle::framework {
 class Variable;
-}  // namespace framework
-}  // namespace paddle
+}  // namespace paddle::framework
 
-namespace paddle {
-namespace framework {
-namespace details {
+namespace paddle::framework::details {
 
 EagerDeletionOpHandle::EagerDeletionOpHandle(
     ir::Node *node,
@@ -213,6 +209,4 @@ std::vector<std::string> EagerDeletionOpHandle::VarsToDelete() const {
   return var_names;
 }
 
-}  // namespace details
-}  // namespace framework
-}  // namespace paddle
+}  // namespace paddle::framework::details
diff --git a/paddle/fluid/framework/details/reduce_op_handle.cc b/paddle/fluid/framework/details/reduce_op_handle.cc
index fe43126ca8abe..05e1693eb650e 100644
--- a/paddle/fluid/framework/details/reduce_op_handle.cc
+++ b/paddle/fluid/framework/details/reduce_op_handle.cc
@@ -26,9 +26,7 @@ PADDLE_DEFINE_EXPORTED_bool(
     false,
     "Whether to make the result of computation deterministic in CPU side.");
 
-namespace paddle {
-namespace framework {
-namespace details {
+namespace paddle::framework::details {
 
 std::once_flag CollectiveContext::init_flag_;
 std::unique_ptr<CollectiveContext> CollectiveContext::context_;
@@ -318,6 +316,4 @@ std::vector<const T *> ReduceOpHandle::GetInputValues(
 }
 
 std::string ReduceOpHandle::Name() const { return "reduce"; }
-}  // namespace details
-}  // namespace framework
-}  // namespace paddle
+}  // namespace paddle::framework::details
diff --git a/paddle/fluid/framework/ir/delete_cast_op_pass_test.cc b/paddle/fluid/framework/ir/delete_cast_op_pass_test.cc
index 17f0c642a60d1..c5480db1ca466 100644
--- a/paddle/fluid/framework/ir/delete_cast_op_pass_test.cc
+++ b/paddle/fluid/framework/ir/delete_cast_op_pass_test.cc
@@ -16,9 +16,7 @@
 #include "paddle/fluid/framework/ir/pass.h"
 #include "paddle/fluid/framework/ir/pass_tester_helper.h"
 
-namespace paddle {
-namespace framework {
-namespace ir {
+namespace paddle::framework::ir {
 
 void AddVarToScope(Scope* param_scope,
                    const std::string& name,
@@ -315,8 +313,6 @@ TEST(ApplyCastPass, basic) {
                         cast_num_in_graph));
 }
 
-}  // namespace ir
-}  // namespace framework
-}  // namespace paddle
+}  // namespace paddle::framework::ir
 
 USE_PASS(delete_cast_op_pass);
diff --git a/paddle/fluid/framework/ir/fusion_group/code_generator.cc b/paddle/fluid/framework/ir/fusion_group/code_generator.cc
index 2e5c2b5be4ac3..defc320495064 100644
--- a/paddle/fluid/framework/ir/fusion_group/code_generator.cc
+++ b/paddle/fluid/framework/ir/fusion_group/code_generator.cc
@@ -17,10 +17,7 @@ limitations under the License. */
 #include "paddle/fluid/framework/ir/fusion_group/code_generator_helper.h"
 #include "paddle/fluid/framework/ir/fusion_group/cuda_resources.h"
 
-namespace paddle {
-namespace framework {
-namespace ir {
-namespace fusion_group {
+namespace paddle::framework::ir::fusion_group {
 
 std::string ExtractDataType(const std::vector<Node*>& nodes) {
   std::string dtype_str = "";
@@ -373,7 +370,4 @@ std::unordered_map<Node*, int> CodeGenerator::EncodeVarNodes(
   return var_ids;
 }
 
-}  // namespace fusion_group
-}  // namespace ir
-}  // namespace framework
-}  // namespace paddle
+}  // namespace paddle::framework::ir::fusion_group
diff --git a/paddle/fluid/framework/ir/merge_layernorm_fuse_pass.cc b/paddle/fluid/framework/ir/merge_layernorm_fuse_pass.cc
index 2e6aaa37808ae..1fbe22ff33021 100644
--- a/paddle/fluid/framework/ir/merge_layernorm_fuse_pass.cc
+++ b/paddle/fluid/framework/ir/merge_layernorm_fuse_pass.cc
@@ -39,9 +39,7 @@
   GET_IR_NODE(layernorm_40_in_bias);  \
   GET_IR_NODE(layernorm_40_in_scale); \
   GET_IR_NODE(layernorm_40_out);
-namespace paddle {
-namespace framework {
-namespace ir {
+namespace paddle::framework::ir {
 MergeLayernormFusePass::MergeLayernormFusePass() {
   AddOpCompat(OpCompat("reshape2"))
       .AddInput("X")
@@ -176,9 +174,7 @@ void MergeLayernormFusePass::ApplyImpl(ir::Graph* graph) const {
   gpd(graph, handler);
   AddStatis(fusion_count);
 }
-}  // namespace ir
-}  // namespace framework
-}  // namespace paddle
+}  // namespace paddle::framework::ir
 REGISTER_PASS(merge_layernorm_fuse_pass,
               paddle::framework::ir::MergeLayernormFusePass);
 REGISTER_PASS_CAPABILITY(merge_layernorm_fuse_pass)
diff --git a/paddle/fluid/framework/ir/multi_devices_graph_pass/add_reader_dependency_pass.cc b/paddle/fluid/framework/ir/multi_devices_graph_pass/add_reader_dependency_pass.cc
index b907869b4a38e..e0b96b69116a4 100644
--- a/paddle/fluid/framework/ir/multi_devices_graph_pass/add_reader_dependency_pass.cc
+++ b/paddle/fluid/framework/ir/multi_devices_graph_pass/add_reader_dependency_pass.cc
@@ -16,9 +16,7 @@
 
 #include "paddle/fluid/framework/ir/pass.h"
 
-namespace paddle {
-namespace framework {
-namespace ir {
+namespace paddle::framework::ir {
 
 class Graph;
 
@@ -106,9 +104,7 @@ void AddReaderDependencyPass::ApplyImpl(Graph *graph) const {
   }
 }
 
-}  // namespace ir
-}  // namespace framework
-}  // namespace paddle
+}  // namespace paddle::framework::ir
 
 REGISTER_PASS(add_reader_dependency_pass,
               paddle::framework::ir::AddReaderDependencyPass);
diff --git a/paddle/fluid/framework/ir/multi_devices_graph_pass/set_reader_device_info_utils.cc b/paddle/fluid/framework/ir/multi_devices_graph_pass/set_reader_device_info_utils.cc
index f4f0e393c2499..72e8baaba5017 100644
--- a/paddle/fluid/framework/ir/multi_devices_graph_pass/set_reader_device_info_utils.cc
+++ b/paddle/fluid/framework/ir/multi_devices_graph_pass/set_reader_device_info_utils.cc
@@ -17,9 +17,7 @@
 #include "paddle/fluid/framework/details/computation_op_handle.h"
 #include "paddle/fluid/operators/reader/lod_tensor_blocking_queue.h"
 
-namespace paddle {
-namespace framework {
-namespace ir {
+namespace paddle::framework::ir {
 
 static std::unordered_set<std::string> ReaderOpSet() {
   return {"create_py_reader"};
@@ -78,6 +76,4 @@ void SetReaderOpDeviceInfo(Graph *graph, size_t dev_cnt, size_t dev_idx) {
   VLOG(10) << "Found op number " << found_op_num;
 }
 
-}  // namespace ir
-}  // namespace framework
-}  // namespace paddle
+}  // namespace paddle::framework::ir
diff --git a/paddle/fluid/framework/ir/onednn/compute_propagate_scales_onednn_pass.cc b/paddle/fluid/framework/ir/onednn/compute_propagate_scales_onednn_pass.cc
index 1c733636ca7b0..cf17f00fa4080 100644
--- a/paddle/fluid/framework/ir/onednn/compute_propagate_scales_onednn_pass.cc
+++ b/paddle/fluid/framework/ir/onednn/compute_propagate_scales_onednn_pass.cc
@@ -21,9 +21,7 @@
 #include "paddle/fluid/framework/ir/graph_helper.h"
 #include "paddle/fluid/framework/op_version_registry.h"
 
-namespace paddle {
-namespace framework {
-namespace ir {
+namespace paddle::framework::ir {
 
 void ComputePropagateScalesMkldnnPass::GetTensorFromVector(
     const std::vector<float>& data_v, phi::DenseTensor* tensor) const {
@@ -516,9 +514,7 @@ void ComputePropagateScalesMkldnnPass::ApplyImpl(ir::Graph* graph) const {
       graph, "has_quant_info", "var_quant_scales", var_quant_scales);
 }
 
-}  // namespace ir
-}  // namespace framework
-}  // namespace paddle
+}  // namespace paddle::framework::ir
 
 REGISTER_PASS(compute_propagate_scales_onednn_pass,
               paddle::framework::ir::ComputePropagateScalesMkldnnPass);
diff --git a/paddle/fluid/framework/ir/onednn/conv_elementwise_add_onednn_fuse_pass.cc b/paddle/fluid/framework/ir/onednn/conv_elementwise_add_onednn_fuse_pass.cc
index 7733730f7d605..14857f3c550d8 100644
--- a/paddle/fluid/framework/ir/onednn/conv_elementwise_add_onednn_fuse_pass.cc
+++ b/paddle/fluid/framework/ir/onednn/conv_elementwise_add_onednn_fuse_pass.cc
@@ -19,9 +19,7 @@
 #include "paddle/fluid/framework/op_version_registry.h"
 #include "paddle/utils/string/pretty_log.h"
 
-namespace paddle {
-namespace framework {
-namespace ir {
+namespace paddle::framework::ir {
 
 ResidualConnectionMKLDNNFusePass::ResidualConnectionMKLDNNFusePass() {
   AddOpCompat(OpCompat("conv2d"))
@@ -305,9 +303,7 @@ void ResidualConnectionMKLDNNFusePass::ApplyImpl(ir::Graph* graph) const {
 
   AddStatis(graph_with_stats.second);
 }
-}  // namespace ir
-}  // namespace framework
-}  // namespace paddle
+}  // namespace paddle::framework::ir
 
 REGISTER_PASS(conv_elementwise_add_onednn_fuse_pass,
               paddle::framework::ir::ResidualConnectionMKLDNNFusePass);
diff --git a/paddle/fluid/framework/ir/onednn/operator_reshape2_onednn_fuse_pass.cc b/paddle/fluid/framework/ir/onednn/operator_reshape2_onednn_fuse_pass.cc
index a21ddd579be3c..f937a1c681b17 100644
--- a/paddle/fluid/framework/ir/onednn/operator_reshape2_onednn_fuse_pass.cc
+++ b/paddle/fluid/framework/ir/onednn/operator_reshape2_onednn_fuse_pass.cc
@@ -19,9 +19,7 @@
 #include "paddle/phi/backends/onednn/onednn_reuse.h"
 #include "paddle/utils/string/pretty_log.h"
 
-namespace paddle {
-namespace framework {
-namespace ir {
+namespace paddle::framework::ir {
 
 using string::PrettyLogDetail;
 
@@ -132,9 +130,7 @@ void FuseOperatorReshape2OneDNNPass::FuseReshape2(Graph *graph,
                     op_type);
 }
 
-}  // namespace ir
-}  // namespace framework
-}  // namespace paddle
+}  // namespace paddle::framework::ir
 
 REGISTER_PASS(operator_reshape2_onednn_fuse_pass,
               paddle::framework::ir::FuseOperatorReshape2OneDNNPass);
diff --git a/paddle/fluid/framework/ir/onednn/squeeze2_transpose2_onednn_fuse_pass.cc b/paddle/fluid/framework/ir/onednn/squeeze2_transpose2_onednn_fuse_pass.cc
index 4af9c6a770436..7ac8edbb6005c 100644
--- a/paddle/fluid/framework/ir/onednn/squeeze2_transpose2_onednn_fuse_pass.cc
+++ b/paddle/fluid/framework/ir/onednn/squeeze2_transpose2_onednn_fuse_pass.cc
@@ -17,9 +17,7 @@
 #include "paddle/phi/backends/onednn/onednn_reuse.h"
 #include "paddle/utils/string/pretty_log.h"
 
-namespace paddle {
-namespace framework {
-namespace ir {
+namespace paddle::framework::ir {
 
 using string::PrettyLogDetail;
 
@@ -77,9 +75,7 @@ void FuseSqueeze2Transpose2OneDNNPass::ApplyImpl(Graph *graph) const {
   }
 }
 
-}  // namespace ir
-}  // namespace framework
-}  // namespace paddle
+}  // namespace paddle::framework::ir
 
 REGISTER_PASS(squeeze2_transpose2_onednn_fuse_pass,
               paddle::framework::ir::FuseSqueeze2Transpose2OneDNNPass);
diff --git a/paddle/fluid/framework/ir/placement_pass_base.cc b/paddle/fluid/framework/ir/placement_pass_base.cc
index ccf2bf22ab57b..718e15b01fd72 100644
--- a/paddle/fluid/framework/ir/placement_pass_base.cc
+++ b/paddle/fluid/framework/ir/placement_pass_base.cc
@@ -18,9 +18,7 @@ limitations under the License. */
 
 #include "paddle/fluid/framework/operator.h"
 
-namespace paddle {
-namespace framework {
-namespace ir {
+namespace paddle::framework::ir {
 
 void PlacementPassBase::ApplyImpl(ir::Graph* graph) const {
   VLOG(3) << "Applies " << GetPlacementName() << " placement strategy.";
@@ -43,6 +41,4 @@ void PlacementPassBase::ApplyImpl(ir::Graph* graph) const {
   }
 }
 
-}  // namespace ir
-}  // namespace framework
-}  // namespace paddle
+}  // namespace paddle::framework::ir
diff --git a/paddle/fluid/framework/ir/preln_elementwise_groupnorm_act_pass.cc b/paddle/fluid/framework/ir/preln_elementwise_groupnorm_act_pass.cc
index 7cbb5c169f63c..3917423754ba4 100644
--- a/paddle/fluid/framework/ir/preln_elementwise_groupnorm_act_pass.cc
+++ b/paddle/fluid/framework/ir/preln_elementwise_groupnorm_act_pass.cc
@@ -18,18 +18,11 @@ limitations under the License. */
 #include "paddle/fluid/framework/ir/graph_pattern_detector.h"
 #include "paddle/fluid/framework/op_version_registry.h"
 
-namespace paddle {
-namespace framework {
-namespace ir {
+namespace paddle::framework::ir {
 class Node;
-}  // namespace ir
-}  // namespace framework
-}  // namespace paddle
+}  // namespace paddle::framework::ir
 
-namespace paddle {
-namespace framework {
-namespace ir {
-namespace patterns {
+namespace paddle::framework::ir::patterns {
 
 struct PrelnGroupNormAct : public PatternBase {
   PrelnGroupNormAct(PDPattern *pattern, const std::string &name_scope)
@@ -92,7 +85,8 @@ void PrelnGroupNormAct::operator()(PDNode *x, PDNode *y, bool with_act) {
   }
 }
 
-}  // namespace patterns
+}  // namespace paddle::framework::ir::patterns
+namespace paddle::framework::ir {
 
 int PrelnGroupNormActFusePass::ApplyAddGNPattern(ir::Graph *graph,
                                                  bool with_act) const {
@@ -203,9 +197,7 @@ void PrelnGroupNormActFusePass::ApplyImpl(ir::Graph *graph) const {
   AddStatis(found_subgraph_count);
 }
 
-}  // namespace ir
-}  // namespace framework
-}  // namespace paddle
+}  // namespace paddle::framework::ir
 
 REGISTER_PASS(preln_elementwise_groupnorm_act_pass,
               paddle::framework::ir::PrelnGroupNormActFusePass);
diff --git a/paddle/fluid/framework/ir/trt_qk_multihead_matmul_fuse_pass.cc b/paddle/fluid/framework/ir/trt_qk_multihead_matmul_fuse_pass.cc
index d68694106b5c7..c6a22c143fb66 100644
--- a/paddle/fluid/framework/ir/trt_qk_multihead_matmul_fuse_pass.cc
+++ b/paddle/fluid/framework/ir/trt_qk_multihead_matmul_fuse_pass.cc
@@ -22,10 +22,7 @@
 #endif
 #include "paddle/phi/kernels/funcs/blas/blas.h"
 
-namespace paddle {
-namespace framework {
-namespace ir {
-namespace patterns {
+namespace paddle::framework::ir::patterns {
 
 //       input_qk   input_v
 //       |q     |k      v
@@ -249,7 +246,8 @@ PDNode* TrtQKMultiHeadMatmulPattern::operator()() {
   return reshape2_qkv_out_var;
 }
 
-}  // namespace patterns
+}  // namespace paddle::framework::ir::patterns
+namespace paddle::framework::ir {
 
 int TrtQkMultiHeadMatmulFusePass::BuildQkFusion(Graph* graph,
                                                 const std::string& name_scope,
@@ -575,9 +573,7 @@ void TrtQkMultiHeadMatmulFusePass::ApplyImpl(Graph* graph) const {
   AddStatis(fusion_count);
 }
 
-}  // namespace ir
-}  // namespace framework
-}  // namespace paddle
+}  // namespace paddle::framework::ir
 
 REGISTER_PASS(trt_qk_multihead_matmul_fuse_pass,
               paddle::framework::ir::TrtQkMultiHeadMatmulFusePass);
diff --git a/paddle/fluid/framework/ir/trt_skip_layernorm_fuse_pass.cc b/paddle/fluid/framework/ir/trt_skip_layernorm_fuse_pass.cc
index 0708218dbd07c..e90cadc782a61 100644
--- a/paddle/fluid/framework/ir/trt_skip_layernorm_fuse_pass.cc
+++ b/paddle/fluid/framework/ir/trt_skip_layernorm_fuse_pass.cc
@@ -22,18 +22,11 @@ limitations under the License. */
 #include "paddle/fluid/inference/tensorrt/helper.h"
 #endif
 
-namespace paddle {
-namespace framework {
-namespace ir {
+namespace paddle::framework::ir {
 class Node;
-}  // namespace ir
-}  // namespace framework
-}  // namespace paddle
+}  // namespace paddle::framework::ir
 
-namespace paddle {
-namespace framework {
-namespace ir {
-namespace patterns {
+namespace paddle::framework::ir::patterns {
 
 struct TrtSkipLayerNorm : public PatternBase {
   TrtSkipLayerNorm(PDPattern *pattern, const std::string &name_scope)
@@ -102,7 +95,8 @@ PDNode *TrtSkipLayerNorm::operator()(PDNode *x, PDNode *y) {
   return layer_norm_out_var;
 }
 
-}  // namespace patterns
+}  // namespace paddle::framework::ir::patterns
+namespace paddle::framework::ir {
 
 void TrtSkipLayerNormFusePass::ApplyImpl(ir::Graph *graph) const {
   PADDLE_ENFORCE_NOT_NULL(
@@ -271,9 +265,7 @@ void TrtSkipLayerNormFusePass::ApplyImpl(ir::Graph *graph) const {
   AddStatis(found_subgraph_count);
 }
 
-}  // namespace ir
-}  // namespace framework
-}  // namespace paddle
+}  // namespace paddle::framework::ir
 
 REGISTER_PASS(trt_skip_layernorm_fuse_pass,
               paddle::framework::ir::TrtSkipLayerNormFusePass);
diff --git a/paddle/fluid/framework/ir/trt_support_nhwc_pass.cc b/paddle/fluid/framework/ir/trt_support_nhwc_pass.cc
index d9907555a17b5..6b49a99c02364 100644
--- a/paddle/fluid/framework/ir/trt_support_nhwc_pass.cc
+++ b/paddle/fluid/framework/ir/trt_support_nhwc_pass.cc
@@ -26,9 +26,7 @@
 #include "paddle/fluid/framework/ir/node.h"
 #include "paddle/phi/common/data_type.h"
 
-namespace paddle {
-namespace framework {
-namespace ir {
+namespace paddle::framework::ir {
 
 namespace {
 
@@ -383,8 +381,6 @@ void TrtSupportNHWCPass::ApplyImpl(Graph *graph) const {
   AddStatis(transposed_ops.size());
 }
 
-}  // namespace ir
-}  // namespace framework
-}  // namespace paddle
+}  // namespace paddle::framework::ir
 
 REGISTER_PASS(trt_support_nhwc_pass, paddle::framework::ir::TrtSupportNHWCPass);
diff --git a/paddle/fluid/framework/new_executor/instruction/instruction_util.cc b/paddle/fluid/framework/new_executor/instruction/instruction_util.cc
index 609fd78106747..e7a05d75f6e99 100644
--- a/paddle/fluid/framework/new_executor/instruction/instruction_util.cc
+++ b/paddle/fluid/framework/new_executor/instruction/instruction_util.cc
@@ -42,8 +42,7 @@
 COMMON_DECLARE_bool(dynamic_static_unified_comm);
 #endif
 
-namespace paddle {
-namespace framework {
+namespace paddle::framework {
 
 std::vector<int> GetValueIds(pir::Value value,
                              const ValueExecutionInfo& value_exec_info) {
@@ -407,5 +406,4 @@ bool GetCondData(const phi::DenseTensor& cond) {
   return cpu_cond->data<bool>()[0];
 }
 
-}  // namespace framework
-}  // namespace paddle
+}  // namespace paddle::framework
diff --git a/paddle/fluid/framework/new_executor/interpretercore.cc b/paddle/fluid/framework/new_executor/interpretercore.cc
index 416d46c01e1f2..d5fe408d53401 100644
--- a/paddle/fluid/framework/new_executor/interpretercore.cc
+++ b/paddle/fluid/framework/new_executor/interpretercore.cc
@@ -35,8 +35,7 @@ PADDLE_DEFINE_EXPORTED_bool(new_executor_use_local_scope,
                             "Use local_scope in new executor(especially used "
                             "in UT), can turn off for better performance");
 
-namespace paddle {
-namespace framework {
+namespace paddle::framework {
 
 InterpreterCore::InterpreterCore(const platform::Place& place,
                                  const BlockDesc& block,
@@ -170,5 +169,4 @@ Variable* InterpreterCore::DebugVar(const std::string& name) const {
   return impl_->DebugVar(name);
 }
 
-}  // namespace framework
-}  // namespace paddle
+}  // namespace paddle::framework
diff --git a/paddle/fluid/imperative/prepared_operator.cc b/paddle/fluid/imperative/prepared_operator.cc
index 9f4f46c60cea4..2a39e664276ed 100644
--- a/paddle/fluid/imperative/prepared_operator.cc
+++ b/paddle/fluid/imperative/prepared_operator.cc
@@ -39,8 +39,7 @@ COMMON_DECLARE_bool(check_nan_inf);
 PD_DECLARE_bool(benchmark);
 COMMON_DECLARE_bool(run_kp_kernel);
 
-namespace paddle {
-namespace imperative {
+namespace paddle::imperative {
 
 static const phi::Kernel empty_kernel;
 static const framework::RuntimeContext empty_ctx({}, {});
@@ -752,5 +751,4 @@ void PreparedOp::Run(const NameVarMap<egr::EagerVariable>& ins,
   }
 }
 
-}  // namespace imperative
-}  // namespace paddle
+}  // namespace paddle::imperative
diff --git a/paddle/fluid/inference/analysis/passes/save_optimized_model_pass.cc b/paddle/fluid/inference/analysis/passes/save_optimized_model_pass.cc
index aaf9439d2b9ed..e8b8c27a24e58 100644
--- a/paddle/fluid/inference/analysis/passes/save_optimized_model_pass.cc
+++ b/paddle/fluid/inference/analysis/passes/save_optimized_model_pass.cc
@@ -20,9 +20,7 @@ limitations under the License. */
 #include "paddle/fluid/framework/ir/graph_helper.h"
 #include "paddle/fluid/framework/scope.h"
 
-namespace paddle {
-namespace inference {
-namespace analysis {
+namespace paddle::inference::analysis {
 
 void SaveOptimizedModelPass::SaveOptimizedModel(Argument* argument) {
   std::string model_opt_cache_dir = argument->optimized_model_save_path();
@@ -137,6 +135,4 @@ std::string SaveOptimizedModelPass::repr() const {
   return "save_optimized_model_pass";
 }
 
-}  // namespace analysis
-}  // namespace inference
-}  // namespace paddle
+}  // namespace paddle::inference::analysis
diff --git a/paddle/fluid/inference/tensorrt/convert/conv3d_op.cc b/paddle/fluid/inference/tensorrt/convert/conv3d_op.cc
index 37a53d31f47b5..547ec74c19fa6 100644
--- a/paddle/fluid/inference/tensorrt/convert/conv3d_op.cc
+++ b/paddle/fluid/inference/tensorrt/convert/conv3d_op.cc
@@ -14,9 +14,7 @@ limitations under the License. */
 
 #include "paddle/fluid/inference/tensorrt/convert/op_converter.h"
 
-namespace paddle {
-namespace inference {
-namespace tensorrt {
+namespace paddle::inference::tensorrt {
 
 template <typename RegistFunc, typename SetDilationFunc>
 void ConvertConv3d(TensorRTEngine* engine,
@@ -192,9 +190,7 @@ class Deconv3dOpConverter : public OpConverter {
   }
 };
 
-}  // namespace tensorrt
-}  // namespace inference
-}  // namespace paddle
+}  // namespace paddle::inference::tensorrt
 
 REGISTER_TRT_OP_CONVERTER(conv3d, Conv3dOpConverter);
 REGISTER_TRT_OP_CONVERTER(conv3d_transpose, Deconv3dOpConverter);
diff --git a/paddle/fluid/inference/tensorrt/convert/leaky_relu_op.cc b/paddle/fluid/inference/tensorrt/convert/leaky_relu_op.cc
index d3fda4cb24e28..f505c36b2ed5c 100644
--- a/paddle/fluid/inference/tensorrt/convert/leaky_relu_op.cc
+++ b/paddle/fluid/inference/tensorrt/convert/leaky_relu_op.cc
@@ -14,9 +14,7 @@ limitations under the License. */
 
 #include "paddle/fluid/inference/tensorrt/convert/op_converter.h"
 
-namespace paddle {
-namespace inference {
-namespace tensorrt {
+namespace paddle::inference::tensorrt {
 
 // LeakyRelu converter from fluid to tensorRT
 class LeakyReluOpConverter : public OpConverter {
@@ -121,8 +119,6 @@ class LeakyReluOpConverter : public OpConverter {
   }
 };
 
-}  // namespace tensorrt
-}  // namespace inference
-}  // namespace paddle
+}  // namespace paddle::inference::tensorrt
 
 REGISTER_TRT_OP_CONVERTER(leaky_relu, LeakyReluOpConverter);
diff --git a/paddle/fluid/inference/tensorrt/convert/matrix_multiply_op.cc b/paddle/fluid/inference/tensorrt/convert/matrix_multiply_op.cc
index 16d6f3f20750c..fd72f8b78f9af 100644
--- a/paddle/fluid/inference/tensorrt/convert/matrix_multiply_op.cc
+++ b/paddle/fluid/inference/tensorrt/convert/matrix_multiply_op.cc
@@ -12,9 +12,7 @@ limitations under the License. */
 #include "paddle/fluid/inference/tensorrt/convert/op_converter.h"
 #include "paddle/phi/common/data_type.h"
 
-namespace paddle {
-namespace inference {
-namespace tensorrt {
+namespace paddle::inference::tensorrt {
 
 /*
  * After trt_map_ops_to_matrix_multiply_pass(mul, matmul, matmul_v2 ->
@@ -266,8 +264,6 @@ class MatrixMultiplyOpConverter : public OpConverter {
   }
 };
 
-}  // namespace tensorrt
-}  // namespace inference
-}  // namespace paddle
+}  // namespace paddle::inference::tensorrt
 
 REGISTER_TRT_OP_CONVERTER(matrix_multiply, MatrixMultiplyOpConverter);
diff --git a/paddle/fluid/inference/tensorrt/convert/multiclass_nms3_op.cc b/paddle/fluid/inference/tensorrt/convert/multiclass_nms3_op.cc
index 107217477d14f..f2d00ab4b4667 100644
--- a/paddle/fluid/inference/tensorrt/convert/multiclass_nms3_op.cc
+++ b/paddle/fluid/inference/tensorrt/convert/multiclass_nms3_op.cc
@@ -13,9 +13,7 @@ limitations under the License. */
 
 #include "paddle/fluid/inference/tensorrt/convert/op_converter.h"
 
-namespace paddle {
-namespace inference {
-namespace tensorrt {
+namespace paddle::inference::tensorrt {
 
 class MultiClassNMS3OpConverter : public OpConverter {
  public:
@@ -170,8 +168,6 @@ class MultiClassNMS3OpConverter : public OpConverter {
   }
 };
 
-}  // namespace tensorrt
-}  // namespace inference
-}  // namespace paddle
+}  // namespace paddle::inference::tensorrt
 
 REGISTER_TRT_OP_CONVERTER(multiclass_nms3, MultiClassNMS3OpConverter);
diff --git a/paddle/fluid/inference/tensorrt/convert/transformer_input_convert_op.cc b/paddle/fluid/inference/tensorrt/convert/transformer_input_convert_op.cc
index 1dca9bb818c38..f7fda67a3643f 100644
--- a/paddle/fluid/inference/tensorrt/convert/transformer_input_convert_op.cc
+++ b/paddle/fluid/inference/tensorrt/convert/transformer_input_convert_op.cc
@@ -15,9 +15,7 @@ limitations under the License. */
 #include "paddle/fluid/inference/tensorrt/convert/op_converter.h"
 #include "paddle/fluid/inference/tensorrt/plugin/transformer_input_output_convert_plugin.h"
 
-namespace paddle {
-namespace inference {
-namespace tensorrt {
+namespace paddle::inference::tensorrt {
 
 /*
  * Convert Transformer Input(pos_id, max_seqlen).
@@ -58,8 +56,6 @@ class TransformerInputConvert : public OpConverter {
   }
 };
 
-}  // namespace tensorrt
-}  // namespace inference
-}  // namespace paddle
+}  // namespace paddle::inference::tensorrt
 
 REGISTER_TRT_OP_CONVERTER(transformer_input_convert, TransformerInputConvert);
diff --git a/paddle/fluid/inference/tensorrt/test_dynamic_engine.cc b/paddle/fluid/inference/tensorrt/test_dynamic_engine.cc
index d87c9af8cfa67..ae12901e7da90 100644
--- a/paddle/fluid/inference/tensorrt/test_dynamic_engine.cc
+++ b/paddle/fluid/inference/tensorrt/test_dynamic_engine.cc
@@ -29,9 +29,7 @@ limitations under the License. */
 #include "paddle/phi/common/float16.h"
 
 using float16 = phi::dtype::float16;
-namespace paddle {
-namespace inference {
-namespace tensorrt {
+namespace paddle::inference::tensorrt {
 
 class TensorRTDynamicShapeValueEngineTest : public ::testing::Test {
  public:
@@ -1049,6 +1047,4 @@ TEST_F(TensorRTDynamicShapeGNTest, test_trt_dynamic_shape_groupnorm) {
 }
 */
 #endif
-}  // namespace tensorrt
-}  // namespace inference
-}  // namespace paddle
+}  // namespace paddle::inference::tensorrt
diff --git a/paddle/fluid/memory/allocation/cpu_allocator.cc b/paddle/fluid/memory/allocation/cpu_allocator.cc
index 398c015627860..426eeeae70e55 100644
--- a/paddle/fluid/memory/allocation/cpu_allocator.cc
+++ b/paddle/fluid/memory/allocation/cpu_allocator.cc
@@ -19,9 +19,7 @@
 #include "paddle/fluid/memory/stats.h"
 #include "paddle/fluid/platform/enforce.h"
 
-namespace paddle {
-namespace memory {
-namespace allocation {
+namespace paddle::memory::allocation {
 
 bool CPUAllocator::IsAllocThreadSafe() const { return true; }
 
@@ -52,6 +50,4 @@ phi::Allocation *CPUAllocator::AllocateImpl(size_t size) {
   HOST_MEMORY_STAT_UPDATE(Reserved, 0, size);
   return new Allocation(p, size, platform::CPUPlace());
 }
-}  // namespace allocation
-}  // namespace memory
-}  // namespace paddle
+}  // namespace paddle::memory::allocation
diff --git a/paddle/fluid/memory/allocation/memory_block_desc.cc b/paddle/fluid/memory/allocation/memory_block_desc.cc
index d20d56a6d05e8..1d1f3c2396921 100644
--- a/paddle/fluid/memory/allocation/memory_block_desc.cc
+++ b/paddle/fluid/memory/allocation/memory_block_desc.cc
@@ -17,9 +17,7 @@ limitations under the License. */
 
 #include "paddle/fluid/memory/allocation/memory_block.h"
 
-namespace paddle {
-namespace memory {
-namespace detail {
+namespace paddle::memory::detail {
 
 MemoryBlock::Desc::Desc(MemoryBlock::Type t,
                         size_t i,
@@ -74,6 +72,4 @@ bool MemoryBlock::Desc::CheckGuards() const {
   return guard_begin == hash(*this, 1) && guard_end == hash(*this, 2);
 }
 
-}  // namespace detail
-}  // namespace memory
-}  // namespace paddle
+}  // namespace paddle::memory::detail
diff --git a/paddle/fluid/operators/collective/c_allreduce_avg_op.cc b/paddle/fluid/operators/collective/c_allreduce_avg_op.cc
index 963ea26321bdb..13d07557f1e7c 100644
--- a/paddle/fluid/operators/collective/c_allreduce_avg_op.cc
+++ b/paddle/fluid/operators/collective/c_allreduce_avg_op.cc
@@ -14,17 +14,14 @@ limitations under the License. */
 
 #include "paddle/fluid/operators/collective/c_allreduce_op.h"
 
-namespace paddle {
-namespace framework {
+namespace paddle::framework {
 class OpDesc;
-}  // namespace framework
-namespace imperative {
+}  // namespace paddle::framework
+namespace paddle::imperative {
 class OpBase;
-}  // namespace imperative
-}  // namespace paddle
+}  // namespace paddle::imperative
 
-namespace paddle {
-namespace operators {
+namespace paddle::operators {
 
 class CAllReduceAvgOpMaker : public CAllReduceOpMaker {
  protected:
@@ -33,8 +30,7 @@ class CAllReduceAvgOpMaker : public CAllReduceOpMaker {
 
 DECLARE_INPLACE_OP_INFERER(AllreduceAvgInplaceInferer, {"X", "Out"});
 
-}  // namespace operators
-}  // namespace paddle
+}  // namespace paddle::operators
 
 namespace ops = paddle::operators;
 
diff --git a/paddle/fluid/operators/collective/partial_send_op.cc b/paddle/fluid/operators/collective/partial_send_op.cc
index cf2a0ece1a7ab..961b8c4cf1382 100644
--- a/paddle/fluid/operators/collective/partial_send_op.cc
+++ b/paddle/fluid/operators/collective/partial_send_op.cc
@@ -14,8 +14,7 @@ limitations under the License. */
 
 #include "paddle/fluid/operators/collective/partial_send_op.h"
 
-namespace paddle {
-namespace operators {
+namespace paddle::operators {
 
 class PartialSendOp : public framework::OperatorWithKernel {
  public:
@@ -84,8 +83,7 @@ Reference: https://docs.nvidia.com/deeplearning/nccl/user-guide/docs/usage/p2p.h
   }
 };
 
-}  // namespace operators
-}  // namespace paddle
+}  // namespace paddle::operators
 
 namespace ops = paddle::operators;
 
diff --git a/paddle/fluid/pir/dialect/distributed/ir/dist_tools.cc b/paddle/fluid/pir/dialect/distributed/ir/dist_tools.cc
index 505b178a452b0..f0d4fcee3b19d 100644
--- a/paddle/fluid/pir/dialect/distributed/ir/dist_tools.cc
+++ b/paddle/fluid/pir/dialect/distributed/ir/dist_tools.cc
@@ -17,8 +17,7 @@
 #include "paddle/common/enforce.h"
 #include "paddle/pir/include/core/operation.h"
 
-namespace paddle {
-namespace dialect {
+namespace paddle::dialect {
 
 bool AllInputAreDist(const std::vector<pir::Value>& inputs) {
   for (auto value : inputs) {
@@ -225,5 +224,4 @@ void CopyLeafOpToMesh(pir::Value value, ProcessMeshAttribute mesh_attr) {
     }
   }
 }
-}  // namespace dialect
-}  // namespace paddle
+}  // namespace paddle::dialect
diff --git a/paddle/fluid/pir/dialect/operator/ir/op_attribute.cc b/paddle/fluid/pir/dialect/operator/ir/op_attribute.cc
index 8a843a8881734..4eb8190eaa111 100644
--- a/paddle/fluid/pir/dialect/operator/ir/op_attribute.cc
+++ b/paddle/fluid/pir/dialect/operator/ir/op_attribute.cc
@@ -16,8 +16,7 @@
 #include "paddle/common/enforce.h"
 #include "paddle/common/errors.h"
 
-namespace paddle {
-namespace dialect {
+namespace paddle::dialect {
 const phi::IntArray &IntArrayAttribute::data() const {
   return storage()->GetAsKey();
 }
@@ -130,8 +129,7 @@ DataLayoutAttribute DataLayoutAttribute::Parse(
       parser.ctx, StringToDataLayoutMap().at(datalayout_token_val));
 }
 
-}  // namespace dialect
-}  // namespace paddle
+}  // namespace paddle::dialect
 
 IR_DEFINE_EXPLICIT_TYPE_ID(paddle::dialect::IntArrayAttribute)
 IR_DEFINE_EXPLICIT_TYPE_ID(paddle::dialect::ScalarAttribute)
diff --git a/paddle/fluid/pir/dialect/operator/transforms/param_to_variable.cc b/paddle/fluid/pir/dialect/operator/transforms/param_to_variable.cc
index 1d93e27c59b0b..78cb8e6460769 100644
--- a/paddle/fluid/pir/dialect/operator/transforms/param_to_variable.cc
+++ b/paddle/fluid/pir/dialect/operator/transforms/param_to_variable.cc
@@ -21,8 +21,7 @@
 #include "paddle/phi/common/data_type.h"
 #include "paddle/phi/core/dense_tensor.h"
 
-namespace paddle {
-namespace dialect {
+namespace paddle::dialect {
 std::shared_ptr<paddle::framework::Variable>
 ParameterConvertInterface::ParameterToVariable(pir::Parameter *parameter) {
   if (parameter->type().isa<DenseTensorType>()) {
@@ -79,7 +78,6 @@ std::unique_ptr<pir::Parameter> ParameterConvertInterface::VariableToParameter(
   }
 }
 
-}  // namespace dialect
-}  // namespace paddle
+}  // namespace paddle::dialect
 
 IR_DEFINE_EXPLICIT_TYPE_ID(paddle::dialect::ParameterConvertInterface)
diff --git a/paddle/fluid/platform/device/gpu/gpu_info.cc b/paddle/fluid/platform/device/gpu/gpu_info.cc
index 358d52d03d31b..d7b164862cd7e 100644
--- a/paddle/fluid/platform/device/gpu/gpu_info.cc
+++ b/paddle/fluid/platform/device/gpu/gpu_info.cc
@@ -68,8 +68,7 @@ PADDLE_DEFINE_EXPORTED_uint64(cuda_memory_async_pool_realease_threshold,
                               "Amount of reserved memory in bytes to hold onto "
                               "before trying to release memory back to the OS");
 
-namespace paddle {
-namespace platform {
+namespace paddle::platform {
 
 void GpuMemoryUsage(size_t *available, size_t *total) {
   size_t actual_available, actual_total;
@@ -719,5 +718,4 @@ void GpuMemsetAsync(void *dst, int value, size_t count, gpuStream_t stream) {
   phi::backends::gpu::GpuMemsetAsync(dst, value, count, stream);
 }
 
-}  // namespace platform
-}  // namespace paddle
+}  // namespace paddle::platform
diff --git a/paddle/fluid/platform/dynload/nccl.cc b/paddle/fluid/platform/dynload/nccl.cc
index 7b0ea3bb7f3c1..ee270918b59c7 100644
--- a/paddle/fluid/platform/dynload/nccl.cc
+++ b/paddle/fluid/platform/dynload/nccl.cc
@@ -14,9 +14,7 @@ limitations under the License. */
 
 #include "paddle/fluid/platform/dynload/nccl.h"
 
-namespace paddle {
-namespace platform {
-namespace dynload {
+namespace paddle::platform::dynload {
 
 #define DEFINE_WRAP(__name) DynLoad__##__name __name
 
@@ -38,6 +36,4 @@ NCCL_RAND_ROUTINE_EACH_AFTER_2703(DEFINE_WRAP)
 NCCL_RAND_ROUTINE_EACH_AFTER_21100(DEFINE_WRAP)
 #endif
 
-}  // namespace dynload
-}  // namespace platform
-}  // namespace paddle
+}  // namespace paddle::platform::dynload
diff --git a/paddle/fluid/prim/api/manual_prim/utils/static_utils.cc b/paddle/fluid/prim/api/manual_prim/utils/static_utils.cc
index 2f76e8bbd966f..43ab21ccd3e06 100644
--- a/paddle/fluid/prim/api/manual_prim/utils/static_utils.cc
+++ b/paddle/fluid/prim/api/manual_prim/utils/static_utils.cc
@@ -23,8 +23,7 @@
 #include "paddle/fluid/prim/utils/static/static_global_utils.h"
 #include "paddle/phi/api/include/tensor.h"
 #include "paddle/phi/core/utils/data_type.h"
-namespace paddle {
-namespace prim {
+namespace paddle::prim {
 using Tensor = paddle::Tensor;
 template <>
 TEST_API Tensor empty<DescTensor>(const paddle::experimental::IntArray& shape,
@@ -69,5 +68,4 @@ void by_pass<DescTensor>(const paddle::Tensor& x, paddle::Tensor* real_out) {
   set_output<DescTensor>(out, real_out);
 }
 
-}  // namespace prim
-}  // namespace paddle
+}  // namespace paddle::prim
diff --git a/paddle/fluid/prim/utils/static/static_global_utils.cc b/paddle/fluid/prim/utils/static/static_global_utils.cc
index 3d1aa2158048d..71179429dc997 100644
--- a/paddle/fluid/prim/utils/static/static_global_utils.cc
+++ b/paddle/fluid/prim/utils/static/static_global_utils.cc
@@ -14,12 +14,10 @@
 
 #include "paddle/fluid/prim/utils/static/static_global_utils.h"
 
-namespace paddle {
-namespace prim {
+namespace paddle::prim {
 StaticCompositeContext* StaticCompositeContext::static_composite_context_ =
     new StaticCompositeContext();
 thread_local bool StaticCompositeContext::enable_bwd_prim_ = false;
 thread_local bool StaticCompositeContext::enable_fwd_prim_ = false;
 thread_local bool StaticCompositeContext::enable_eager_prim_ = false;
-}  // namespace prim
-}  // namespace paddle
+}  // namespace paddle::prim
diff --git a/paddle/fluid/pybind/graph.cc b/paddle/fluid/pybind/graph.cc
index 6acba237ba928..4e5329bbf2bfc 100644
--- a/paddle/fluid/pybind/graph.cc
+++ b/paddle/fluid/pybind/graph.cc
@@ -47,8 +47,7 @@ using paddle::framework::ir::NodeComp;
 using paddle::framework::ir::TopologySortOperations;
 using pybind11::return_value_policy;
 
-namespace paddle {
-namespace pybind {
+namespace paddle::pybind {
 void BindGraph(py::module *m) {
   m->def("graph_safe_remove_nodes",
          [](Graph *graph, const std::unordered_set<const Node *> &nodes) {
@@ -408,5 +407,4 @@ void BindPass(py::module *m) {
          });
 }
 
-}  // namespace pybind
-}  // namespace paddle
+}  // namespace paddle::pybind
diff --git a/paddle/phi/api/lib/context_pool.cc b/paddle/phi/api/lib/context_pool.cc
index ee1e21a58e2f1..e2eb1af09d8a5 100644
--- a/paddle/phi/api/lib/context_pool.cc
+++ b/paddle/phi/api/lib/context_pool.cc
@@ -23,8 +23,7 @@ limitations under the License. */
 #include "paddle/phi/core/cuda_stream.h"
 #endif
 
-namespace paddle {
-namespace experimental {
+namespace paddle::experimental {
 
 void DeviceContextPool::SyncDeviceContext(const Place& place) {
   if (!phi::DeviceContextPool::IsInitialized()) {
@@ -64,8 +63,7 @@ phi::DeviceContext* DeviceContextPool::GetMutable(const Place& place) {
   return const_cast<phi::DeviceContext*>(Get(place));  // NOLINT
 }
 
-}  // namespace experimental
-}  // namespace paddle
+}  // namespace paddle::experimental
 
 namespace paddle {
 
diff --git a/paddle/phi/backends/dynload/cublas.cc b/paddle/phi/backends/dynload/cublas.cc
index 2fe9ae774bf7a..b870a90cb091c 100644
--- a/paddle/phi/backends/dynload/cublas.cc
+++ b/paddle/phi/backends/dynload/cublas.cc
@@ -14,8 +14,7 @@ limitations under the License. */
 
 #include "paddle/phi/backends/dynload/cublas.h"
 
-namespace phi {
-namespace dynload {
+namespace phi::dynload {
 std::once_flag cublas_dso_flag;
 void *cublas_dso_handle = nullptr;
 
@@ -34,5 +33,4 @@ CUBLAS_BLAS_ROUTINE_EACH_R3(DEFINE_WRAP);
 #ifdef CUBLAS_BLAS_ROUTINE_EACH_R4
 CUBLAS_BLAS_ROUTINE_EACH_R4(DEFINE_WRAP);
 #endif
-}  // namespace dynload
-}  // namespace phi
+}  // namespace phi::dynload
diff --git a/paddle/phi/backends/dynload/cusparse.cc b/paddle/phi/backends/dynload/cusparse.cc
index ce8f87dc3cdfa..9d89b746df5b7 100644
--- a/paddle/phi/backends/dynload/cusparse.cc
+++ b/paddle/phi/backends/dynload/cusparse.cc
@@ -14,8 +14,7 @@ limitations under the License. */
 
 #include "paddle/phi/backends/dynload/cusparse.h"
 
-namespace phi {
-namespace dynload {
+namespace phi::dynload {
 
 std::once_flag cusparse_dso_flag;
 void *cusparse_dso_handle;
@@ -34,5 +33,4 @@ CUSPARSE_ROUTINE_EACH_R2(DEFINE_WRAP);
 CUSPARSE_ROUTINE_EACH_R3(DEFINE_WRAP);
 #endif
 
-}  // namespace dynload
-}  // namespace phi
+}  // namespace phi::dynload
diff --git a/paddle/phi/core/distributed/auto_parallel/dist_attr.cc b/paddle/phi/core/distributed/auto_parallel/dist_attr.cc
index 62fbd97c46ab2..98dfa339589a5 100644
--- a/paddle/phi/core/distributed/auto_parallel/dist_attr.cc
+++ b/paddle/phi/core/distributed/auto_parallel/dist_attr.cc
@@ -21,8 +21,7 @@ limitations under the License. */
 #include "glog/logging.h"
 #include "paddle/phi/core/distributed/auto_parallel/proto_helper.h"
 
-namespace phi {
-namespace distributed {
+namespace phi::distributed {
 using phi::distributed::auto_parallel::str_join;
 using phi::distributed::auto_parallel::TensorDistAttrProto;
 
@@ -450,5 +449,4 @@ bool TensorDistAttr::is_partial(int64_t mesh_axis) const {
 
 void TensorDistAttr::set_skip_check_mesh(bool skip) { skip_check_mesh_ = skip; }
 
-}  // namespace distributed
-}  // namespace phi
+}  // namespace phi::distributed
diff --git a/paddle/phi/core/distributed/auto_parallel/reshard/x_to_r_reshard_function.cc b/paddle/phi/core/distributed/auto_parallel/reshard/x_to_r_reshard_function.cc
index bd415480d64e9..947a4b77f6961 100644
--- a/paddle/phi/core/distributed/auto_parallel/reshard/x_to_r_reshard_function.cc
+++ b/paddle/phi/core/distributed/auto_parallel/reshard/x_to_r_reshard_function.cc
@@ -25,8 +25,7 @@
 #include "paddle/phi/kernels/p_recv_kernel.h"
 #include "paddle/phi/kernels/p_send_kernel.h"
 
-namespace phi {
-namespace distributed {
+namespace phi::distributed {
 
 bool XToRShrinkReshardFunction::IsSuitable(
     const DistTensor& in, const TensorDistAttr& out_dist_attr) {
@@ -130,5 +129,4 @@ void XToRShrinkReshardFunction::Eval(phi::DeviceContext* dev_ctx,
   }
 }
 
-}  // namespace distributed
-}  // namespace phi
+}  // namespace phi::distributed
diff --git a/paddle/phi/kernels/funcs/concat_and_split_functor.cc b/paddle/phi/kernels/funcs/concat_and_split_functor.cc
index fd49748666a6e..c42bbbd3a5318 100644
--- a/paddle/phi/kernels/funcs/concat_and_split_functor.cc
+++ b/paddle/phi/kernels/funcs/concat_and_split_functor.cc
@@ -14,8 +14,7 @@ limitations under the License. */
 
 #include "paddle/phi/kernels/funcs/concat_and_split_functor.h"
 
-namespace phi {
-namespace funcs {
+namespace phi::funcs {
 
 /*
  * All tensors' dimension should be the same and the values of
@@ -132,5 +131,4 @@ struct SplitFunctor<phi::CPUContext, T> {
 
 FOR_ALL_TYPES(DEFINE_FUNCTOR);
 
-}  // namespace funcs
-}  // namespace phi
+}  // namespace phi::funcs
diff --git a/paddle/phi/kernels/funcs/matrix_inverse.cc b/paddle/phi/kernels/funcs/matrix_inverse.cc
index c316970e6a560..940e0ea3146ec 100644
--- a/paddle/phi/kernels/funcs/matrix_inverse.cc
+++ b/paddle/phi/kernels/funcs/matrix_inverse.cc
@@ -16,8 +16,7 @@ limitations under the License. */
 
 #include "paddle/phi/kernels/funcs/blas/blas.h"
 
-namespace phi {
-namespace funcs {
+namespace phi::funcs {
 
 template <typename Context, typename T>
 void MatrixInverseFunctor<Context, T>::operator()(const Context& dev_ctx,
@@ -29,5 +28,4 @@ void MatrixInverseFunctor<Context, T>::operator()(const Context& dev_ctx,
 template class MatrixInverseFunctor<CPUContext, float>;
 template class MatrixInverseFunctor<CPUContext, double>;
 
-}  // namespace funcs
-}  // namespace phi
+}  // namespace phi::funcs
diff --git a/paddle/phi/kernels/funcs/sequence_pooling.cc b/paddle/phi/kernels/funcs/sequence_pooling.cc
index f4ee9c323366e..1fdaadfea01a1 100644
--- a/paddle/phi/kernels/funcs/sequence_pooling.cc
+++ b/paddle/phi/kernels/funcs/sequence_pooling.cc
@@ -21,8 +21,7 @@ limitations under the License. */
 #include "paddle/phi/kernels/funcs/jit/kernels.h"
 #include "paddle/phi/kernels/funcs/math_function.h"
 
-namespace phi {
-namespace funcs {
+namespace phi::funcs {
 
 template <typename T,
           int MajorType = Eigen::RowMajor,
@@ -498,5 +497,4 @@ template class SequencePoolFunctor<phi::CPUContext, double>;
 template class SequencePoolGradFunctor<phi::CPUContext, float>;
 template class SequencePoolGradFunctor<phi::CPUContext, double>;
 
-}  // namespace funcs
-}  // namespace phi
+}  // namespace phi::funcs
diff --git a/paddle/phi/kernels/fusion/cpu/fusion_seqconv_eltadd_relu_kernel.cc b/paddle/phi/kernels/fusion/cpu/fusion_seqconv_eltadd_relu_kernel.cc
index 4ff18849316d8..456d3370990cb 100644
--- a/paddle/phi/kernels/fusion/cpu/fusion_seqconv_eltadd_relu_kernel.cc
+++ b/paddle/phi/kernels/fusion/cpu/fusion_seqconv_eltadd_relu_kernel.cc
@@ -23,8 +23,7 @@
 #include "paddle/phi/kernels/funcs/blas/blas.h"
 #include "paddle/phi/kernels/funcs/fc_functor.h"
 
-namespace phi {
-namespace fusion {
+namespace phi::fusion {
 
 template <typename T, typename Context>
 void FusionSeqConvEltAddReluKernel(const Context& dev_ctx,
@@ -148,8 +147,7 @@ void FusionSeqConvEltAddReluKernel(const Context& dev_ctx,
      true);
 }
 
-}  // namespace fusion
-}  // namespace phi
+}  // namespace phi::fusion
 
 PD_REGISTER_KERNEL(fusion_seqconv_eltadd_relu,
                    CPU,