remove fluid symbol depend in sync bn (#47122)

paddle/phi/kernels/gpu/sync_batch_norm_kernel.cu

@@ -18,6 +18,26 @@
 #include "paddle/phi/kernels/gpu/sync_batch_norm_utils.h"
 
 namespace phi {
+namespace detail {
+
+ccl::CCLComm GetCCLComm(const Place &place, int global_gid) {
+#if defined(PADDLE_WITH_NCCL) || defined(PADDLE_WITH_RCCL)
+  ncclComm_t comm = nullptr;
+
+  if (paddle::distributed::ProcessGroupMapFromGid::getInstance()->has(
+          global_gid)) {
+    auto *nccl_pg = static_cast<paddle::distributed::ProcessGroupNCCL *>(
+        paddle::distributed::ProcessGroupMapFromGid::getInstance()->get(
+            global_gid));
+    comm = nccl_pg->NCCLComm(place);
+  }
+  return comm;
+#else
+  return nullptr;
+#endif
+}
+
+}  // namespace detail
 
 template <typename T, typename Context>
 void SyncBatchNormKernel(const Context &ctx,
@@ -102,16 +122,8 @@ void SyncBatchNormKernel(const Context &ctx,
     }
 
 #if defined(PADDLE_WITH_NCCL) || defined(PADDLE_WITH_RCCL)
-    int global_gid = 0;
-    ncclComm_t comm = nullptr;
-
-    if (paddle::distributed::ProcessGroupMapFromGid::getInstance()->has(
-            global_gid)) {
-      auto *nccl_pg = static_cast<paddle::distributed::ProcessGroupNCCL *>(
-          paddle::distributed::ProcessGroupMapFromGid::getInstance()->get(
-              global_gid));
-      comm = nccl_pg->NCCLComm(x.place());
-    } else {
+    ncclComm_t comm = static_cast<ncclComm_t>(detail::GetCCLComm(x.place(), 0));
+    if (comm == nullptr) {
       comm = ctx.nccl_comm();
     }
 

paddle/phi/kernels/sync_batch_norm_kernel.h

@@ -16,9 +16,23 @@
 
 #include <string>
 
+#include "paddle/phi/backends/c_comm_lib.h"
 #include "paddle/phi/core/dense_tensor.h"
 
 namespace phi {
+namespace detail {
+
+// FIXME(paddle-dev): Since the singleton of ProcessGroup in fluid is used in
+// SyncBN, the fluid symbol will be dependent on external hardware access.
+// Here, the part that depends on the fluid symbol is individually encapsulated
+// as a temporary function to isolate external symbol dependencies.
+// In the future, the dependence on the singleton in fluid in SyncBN needs
+// to be removed.
+// In principle, the PHI Kernel cannot use the global singleton internally,
+// and the required members need to be passed in from the eucalyptus tree.
+ccl::CCLComm GetCCLComm(const Place& place, int global_gid = 0);
+
+}  // namespace detail
 
 template <typename T, typename Context>
 void SyncBatchNormKernel(const Context& dev_ctx,