[core] Creating non-linux implementation for sysfs_cgroup_driver.

python/ray/util/collective/util.py

@@ -1,6 +1,6 @@
 """Some utility class for Collectives."""
-import logging
 import asyncio
+import logging
 
 import ray
 

src/ray/common/cgroup2/BUILD.bazel

@@ -12,7 +12,10 @@ ray_cc_library(
         ":is_linux": ["cgroup_manager.cc"],
         "//conditions:default": ["noop_cgroup_manager.cc"],
     }),
-    hdrs = ["cgroup_manager.h"],
+    hdrs = [
+        "cgroup_manager.h",
+        "scoped_cgroup_operation.h",
+    ],
     visibility = ["//visibility:public"],
     deps = [
         ":cgroup_driver_interface",
@@ -21,7 +24,6 @@ ray_cc_library(
         "//src/ray/common:status_or",
     ] + select({
         ":is_linux": [
-            ":scoped_cgroup_operation",
             "//src/ray/util:logging",
             "@com_google_absl//absl/strings",
         ],
@@ -55,35 +57,28 @@ ray_cc_library(
 
 ray_cc_library(
     name = "sysfs_cgroup_driver",
-    srcs = ["sysfs_cgroup_driver.cc"],
+    srcs = select({
+        ":is_linux": ["sysfs_cgroup_driver.cc"],
+        "//conditions:default": ["noop_sysfs_cgroup_driver.cc"],
+    }),
     hdrs = [
         "sysfs_cgroup_driver.h",
     ],
-    target_compatible_with = [
-        "@platforms//os:linux",
-    ],
     visibility = ["//visibility:public"],
     deps = [
         ":cgroup_driver_interface",
         "//src/ray/common:status",
         "//src/ray/common:status_or",
-        "//src/ray/util:logging",
-        "@com_google_absl//absl/strings",
-    ],
+    ] + select({
+        ":is_linux": [
+            "//src/ray/util:logging",
+            "@com_google_absl//absl/strings",
+        ],
+        "//conditions:default": [],
+    }),
 )
 
 # Private Targets.
-ray_cc_library(
-    name = "scoped_cgroup_operation",
-    hdrs = [
-        "scoped_cgroup_operation.h",
-    ],
-    target_compatible_with = [
-        "@platforms//os:linux",
-    ],
-    visibility = [":__subpackages__"],
-)
-
 ray_cc_library(
     name = "fake_cgroup_driver",
     hdrs = [

src/ray/common/cgroup2/noop_sysfs_cgroup_driver.cc

@@ -0,0 +1,74 @@
+// Copyright 2025 The Ray Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//  http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#include <string>
+#include <unordered_set>
+
+#include "ray/common/cgroup2/sysfs_cgroup_driver.h"
+#include "ray/common/status.h"
+#include "ray/common/status_or.h"
+
+namespace ray {
+Status SysFsCgroupDriver::CheckCgroupv2Enabled() { return Status::OK(); }
+
+Status SysFsCgroupDriver::CheckCgroup(const std::string &cgroup_path) {
+  return Status::OK();
+}
+
+Status SysFsCgroupDriver::CreateCgroup(const std::string &cgroup_path) {
+  return Status::OK();
+}
+
+Status SysFsCgroupDriver::DeleteCgroup(const std::string &cgroup_path) {
+  return Status::OK();
+}
+
+StatusOr<std::unordered_set<std::string>> SysFsCgroupDriver::GetAvailableControllers(
+    const std::string &cgroup_dir) {
+  return std::unordered_set<std::string>{};
+}
+
+StatusOr<std::unordered_set<std::string>> SysFsCgroupDriver::GetEnabledControllers(
+    const std::string &cgroup_dir) {
+  return std::unordered_set<std::string>{};
+}
+
+Status SysFsCgroupDriver::MoveAllProcesses(const std::string &from,
+                                           const std::string &to) {
+  return Status::OK();
+}
+
+Status SysFsCgroupDriver::EnableController(const std::string &cgroup_path,
+                                           const std::string &controller) {
+  return Status::OK();
+}
+
+Status SysFsCgroupDriver::DisableController(const std::string &cgroup_path,
+                                            const std::string &controller) {
+  return Status::OK();
+}
+
+Status SysFsCgroupDriver::AddConstraint(const std::string &cgroup_path,
+                                        const std::string &controller,
+                                        const std::string &constraint,
+                                        const std::string &constraint_value) {
+  return Status::OK();
+}
+
+StatusOr<std::unordered_set<std::string>> SysFsCgroupDriver::ReadControllerFile(
+    const std::string &controller_file_path) {
+  return std::unordered_set<std::string>{};
+}
+
+}  // namespace ray

src/ray/common/cgroup2/sysfs_cgroup_driver.cc

@@ -37,6 +37,12 @@
 #include "ray/common/status.h"
 #include "ray/common/status_or.h"
 
+// Used to identify if a filesystem is mounted using cgroupv2.
+// See: https://docs.kernel.org/admin-guide/cgroup-v2.html#mounting
+#ifndef CGROUP2_SUPER_MAGIC
+#define CGROUP2_SUPER_MAGIC 0x63677270
+#endif
+
 namespace ray {
 Status SysFsCgroupDriver::CheckCgroupv2Enabled() {
   FILE *fp = setmntent(mount_file_path_.c_str(), "r");

src/ray/common/cgroup2/sysfs_cgroup_driver.h

@@ -13,8 +13,10 @@
 // limitations under the License.
 #pragma once
 
-#include <linux/magic.h>
-#include <mntent.h>
+// TODO(#54703): SysFsCgroupDriver should not be a public target.
+// It will be hidden behind a CgroupManagerFactory which will create
+// an appropriate depending on configuration and platform.
+// #include <mntent.h>
 
 #include <string>
 #include <unordered_set>
@@ -24,12 +26,6 @@
 #include "ray/common/status.h"
 #include "ray/common/status_or.h"
 
-// Used to identify if a filesystem is mounted using cgroupv2.
-// See: https://docs.kernel.org/admin-guide/cgroup-v2.html#mounting
-#ifndef CGROUP2_SUPER_MAGIC
-#define CGROUP2_SUPER_MAGIC 0x63677270
-#endif
-
 namespace ray {
 
 /**
@@ -51,7 +47,7 @@ class SysFsCgroupDriver : public CgroupDriverInterface {
    *
    * @param mount_file_path only used for testing.
    */
-  explicit SysFsCgroupDriver(std::string mount_file_path = MOUNTED)
+  explicit SysFsCgroupDriver(std::string mount_file_path = kMountFilePath)
       : mount_file_path_(std::move(mount_file_path)) {}
 
   ~SysFsCgroupDriver() override = default;
@@ -280,5 +276,6 @@ class SysFsCgroupDriver : public CgroupDriverInterface {
   static constexpr std::string_view kCgroupSubtreeControlFilename =
       "cgroup.subtree_control";
   static constexpr std::string_view kCgroupControllersFilename = "cgroup.controllers";
+  static inline std::string kMountFilePath = "/mnt/mtab";
 };
 }  // namespace ray