Removes deprecated ITEX_TILE_AS_DEVICE environment variable. (#2717)

Author: pkourdis

itex/core/devices/gpu/itex_gpu_runtime.cc

@@ -115,7 +115,6 @@ class DevicePool {
     static std::vector<ITEX_GPUDevice> devices;
 
     std::call_once(init_device_flag, []() {
-      std::vector<ITEX_GPUDevice> root_devices;
       // Get root device list from platform list.
       auto platform_list = sycl::platform::get_platforms();
       for (const auto& platform : platform_list) {
@@ -131,43 +130,12 @@ class DevicePool {
           auto device_list = platform.get_devices();
           for (const auto& device : device_list) {
             if (device.is_gpu()) {
-              root_devices.push_back(device);
+              devices.push_back(device);
             }
           }
         }
       }
 
-      if (TileAsDevice()) {
-        // If ITEX_TILE_AS_DEVICE is true.
-        // Create sub devices from root devices:
-        //   If succ, add sub devices into devices list
-        //   If fail, add root devices into devices list
-        constexpr auto partition_by_affinity =
-            sycl::info::partition_property::partition_by_affinity_domain;
-        constexpr auto next_partitionable =
-            sycl::info::partition_affinity_domain::next_partitionable;
-        for (const auto& root_device : root_devices) {
-          std::vector<ITEX_GPUDevice> sub_devices;
-          auto max_sub_devices =
-              root_device
-                  .get_info<sycl::info::device::partition_max_sub_devices>();
-          if (max_sub_devices == 0) {
-            ITEX_LOG(INFO) << "number of sub-devices is zero, expose root "
-                              "device.";
-            devices.push_back(root_device);
-          } else {
-            sub_devices = root_device.create_sub_devices<partition_by_affinity>(
-                next_partitionable);
-            devices.insert(devices.end(), sub_devices.begin(),
-                           sub_devices.end());
-          }
-        }
-      } else {
-        // If ITEX_TILE_AS_DEVICE is false.
-        // Only set root device as device list.
-        devices = std::move(root_devices);
-      }
-
       size_t num_device = devices.size();
 
       if (num_device <= 0) {

itex/core/devices/xpu_device_util.h

@@ -84,32 +84,4 @@ void DeviceMemcpy(void* dst, const void* src, size_t size, void* stream) {
 
 }  // namespace itex
 
-// ITEX_TILE_AS_DEVICE
-//   True (default behaviour): Tile as an individual device in device list
-//   False: Only root device as an individual device in
-//   device list
-inline bool TileAsDevice() {
-  bool tile_as_device;
-  if (std::getenv(std::string("ITEX_ENABLE_TILE_AS_DEVICE").c_str())) {
-    ITEX_CHECK_OK(itex::ReadBoolFromEnvVar("ITEX_ENABLE_TILE_AS_DEVICE", true,
-                                           &tile_as_device));
-    ITEX_LOG(WARNING)
-        << "`ITEX_ENABLE_TILE_AS_DEVICE` will be deprecated, "
-           "please use `ZE_FLAT_DEVICE_HIERARCHY` instead, refering to "
-           "https://spec.oneapi.io/level-zero/latest/core/"
-           "PROG.html#device-hierarchy.";
-  } else if (std::getenv(std::string("ITEX_TILE_AS_DEVICE").c_str())) {
-    ITEX_CHECK_OK(
-        itex::ReadBoolFromEnvVar("ITEX_TILE_AS_DEVICE", true, &tile_as_device));
-    ITEX_LOG(WARNING)
-        << "`ITEX_TILE_AS_DEVICE` will be deprecated, "
-           "please use `ZE_FLAT_DEVICE_HIERARCHY` instead, refering to "
-           "https://spec.oneapi.io/level-zero/latest/core/"
-           "PROG.html#device-hierarchy.";
-  } else {
-    tile_as_device = true;
-  }
-  return tile_as_device;
-}
-
 #endif  // ITEX_CORE_DEVICES_XPU_DEVICE_UTIL_H_

itex/core/graph/xpu_graph.cc

@@ -47,9 +47,6 @@ void InitGlobalSetting(const OptimizerConfigFlags& config) {
       {"ITEX_REMAPPER", config.enable_remapper},
       {"ITEX_LAYOUT_OPT", config.enable_layout_opt},
       {"ITEX_AUTO_MIXED_PRECISION", config.enable_auto_mixed_precision},
-#ifndef INTEL_CPU_ONLY
-      {"ITEX_TILE_AS_DEVICE", TileAsDevice},
-#endif
       {"ITEX_CACHE_ONEDNN_OBJECT", false},
       {"_ITEX_ONEDNN_GRAPH_ALL_TYPE", config.enable_onednn_graph_all_type},
       {"_ITEX_ONEDNN_GRAPH_COMPILER_BACKEND",