diff --git a/include/xgboost/c_api.h b/include/xgboost/c_api.h
index 99831478f234..849fcbb8d58b 100644
--- a/include/xgboost/c_api.h
+++ b/include/xgboost/c_api.h
@@ -506,17 +506,9 @@ XGB_DLL int XGProxyDMatrixSetDataCSR(DMatrixHandle handle, char const *indptr,
 XGB_DLL int XGImportRecordBatch(DataIterHandle data_handle, void* ptr_array, void* ptr_schema);
 
 XGB_DLL int XGDMatrixCreateFromArrowCallback(
-    XGDMatrixCallbackNext *next,
-    float missing,
-    int nthread,
-    const char* label_col_name,
-    const char* label_lb_col_name,
-    const char* label_ub_col_name,
-    const char* weight_col_name,
-    const char* base_margin_col_name,
-    const char* qid_col_name,
-    DMatrixHandle *out);
-
+    XGDMatrixCallbackNext *next, char const *json_config, const char *label_col_name,
+    const char *label_lb_col_name, const char *label_ub_col_name, const char *weight_col_name,
+    const char *base_margin_col_name, const char *qid_col_name, DMatrixHandle *out);
 
 /*
  * ==========================- End data callback APIs ==========================
diff --git a/python-package/xgboost/data.py b/python-package/xgboost/data.py
index 75a54287e22a..8165a6090636 100644
--- a/python-package/xgboost/data.py
+++ b/python-package/xgboost/data.py
@@ -473,16 +473,18 @@ def _is_arrow(data):
 
 def _from_arrow(
     data,
-    missing,
-    nthread,
+    missing: float,
+    nthread: int,
     feature_names: Optional[List[str]],
     feature_types: Optional[List[str]],
-    enable_categorical: bool
+    enable_categorical: bool,
 ) -> Tuple[ctypes.c_void_p, Optional[List[str]], Optional[List[str]]]:
-    if not all(pa.types.is_integer(t) or pa.types.is_floating(t)
-                for t in data.schema.types):
+    if not all(
+        pa.types.is_integer(t) or pa.types.is_floating(t) for t in data.schema.types
+    ):
         raise ValueError(
-            'Features in dataset can only be integers or floating point number')
+            "Features in dataset can only be integers or floating point number"
+        )
     if enable_categorical:
         raise ValueError("categorical data in datatable is not supported yet.")
 
@@ -490,17 +492,19 @@ def _from_arrow(
     it = RecordBatchDataIter(rb_iter)
     next_callback = ctypes.CFUNCTYPE(ctypes.c_int, ctypes.c_void_p)(it.next)
     handle = ctypes.c_void_p()
+
+    args = {"missing": missing, "nthread": nthread}
+    config = bytes(json.dumps(args), "utf-8")
     ret = _LIB.XGDMatrixCreateFromArrowCallback(
         next_callback,
-        ctypes.c_float(missing),
-        ctypes.c_int(nthread),
+        config,
         ctypes.POINTER(ctypes.c_char_p)(),
         ctypes.POINTER(ctypes.c_char_p)(),
         ctypes.POINTER(ctypes.c_char_p)(),
         ctypes.POINTER(ctypes.c_char_p)(),
         ctypes.POINTER(ctypes.c_char_p)(),
         ctypes.POINTER(ctypes.c_char_p)(),
-        ctypes.byref(handle)
+        ctypes.byref(handle),
     )
     _check_call(ret)
     return (handle, feature_names, feature_types)
diff --git a/src/c_api/c_api.cc b/src/c_api/c_api.cc
index a3d300827211..77eeabffce3b 100644
--- a/src/c_api/c_api.cc
+++ b/src/c_api/c_api.cc
@@ -432,8 +432,7 @@ XGB_DLL int XGImportRecordBatch(DataIterHandle data_handle, void* ptr_array, voi
 
 XGB_DLL int XGDMatrixCreateFromArrowCallback(
     XGDMatrixCallbackNext *next,
-    float missing,
-    int nthread,
+    char const* json_config,
     const char* label_col_name,
     const char* label_lb_col_name,
     const char* label_ub_col_name,
@@ -442,7 +441,10 @@ XGB_DLL int XGDMatrixCreateFromArrowCallback(
     const char* qid_col_name,
     DMatrixHandle *out) {
   API_BEGIN();
-  int n_threads = common::OmpGetNumThreads(nthread);
+  auto config = Json::Load(StringView{json_config});
+  auto missing = GetMissing(config);
+  int32_t n_threads = get<Integer const>(config["nthread"]);
+  n_threads = common::OmpGetNumThreads(n_threads);
   data::RecordBatchesIterAdapter adapter(next,
                                          n_threads,
                                          label_col_name,
@@ -452,7 +454,7 @@ XGB_DLL int XGDMatrixCreateFromArrowCallback(
                                          base_margin_col_name,
                                          qid_col_name);
   *out = new std::shared_ptr<DMatrix>(
-      DMatrix::Create(&adapter, missing, nthread));
+      DMatrix::Create(&adapter, missing, n_threads));
   API_END();
 }
 
diff --git a/src/data/simple_dmatrix.cc b/src/data/simple_dmatrix.cc
index c859ae5e7149..47e875f1d78a 100644
--- a/src/data/simple_dmatrix.cc
+++ b/src/data/simple_dmatrix.cc
@@ -242,11 +242,10 @@ template SimpleDMatrix::SimpleDMatrix(
         *adapter,
     float missing, int nthread);
 
-template<>
-SimpleDMatrix::SimpleDMatrix(RecordBatchesIterAdapter* adapter,
-                            float missing, int nthread) {
-  constexpr uint64_t default_max = std::numeric_limits<uint64_t>::max();
-  uint64_t last_group_id = default_max;
+template <>
+SimpleDMatrix::SimpleDMatrix(RecordBatchesIterAdapter* adapter, float missing, int nthread) {
+  constexpr uint64_t kDefaultMax = std::numeric_limits<uint64_t>::max();
+  uint64_t last_group_id = kDefaultMax;
   bst_uint group_size = 0;
   auto& offset_vec = sparse_page_->offset.HostVector();
   auto& data_vec = sparse_page_->data.HostVector();
@@ -353,7 +352,7 @@ SimpleDMatrix::SimpleDMatrix(RecordBatchesIterAdapter* adapter,
         // get group
         for (size_t i = 0; i < batches[i]->Size(); ++i) {
           const uint64_t cur_group_id = batches[i]->Qid()[i];
-          if (last_group_id == default_max || last_group_id != cur_group_id) {
+          if (last_group_id == kDefaultMax || last_group_id != cur_group_id) {
             info_.group_ptr_.push_back(group_size);
           }
           last_group_id = cur_group_id;
@@ -362,7 +361,7 @@ SimpleDMatrix::SimpleDMatrix(RecordBatchesIterAdapter* adapter,
       }
     }
   }
-  if (last_group_id != default_max) {
+  if (last_group_id != kDefaultMax) {
     if (group_size > info_.group_ptr_.back()) {
       info_.group_ptr_.push_back(group_size);
     }