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 * Copyright (c) 2019, 2024, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
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#ifndef CGROUP_V1_SUBSYSTEM_LINUX_HPP
#define CGROUP_V1_SUBSYSTEM_LINUX_HPP

#include "runtime/os.hpp"
#include "memory/allocation.hpp"
#include "cgroupSubsystem_linux.hpp"
#include "cgroupUtil_linux.hpp"

// Cgroups version 1 specific implementation

class CgroupV1Controller: public CgroupController {
  private:
    /* mountinfo contents */
    char* _root;
    bool _read_only;

    /* Constructed subsystem directory */
    char* _path;

  public:
    CgroupV1Controller(char *root,
                       char *mountpoint,
                       bool ro) : _root(os::strdup(root)),
                                  _read_only(ro),
                                  _path(nullptr) {
      _cgroup_path = nullptr;
      _mount_point = os::strdup(mountpoint);
    }
    // Shallow copy constructor
    CgroupV1Controller(const CgroupV1Controller& o) : _root(o._root),
                                                      _read_only(o._read_only),
                                                      _path(o._path) {
      _cgroup_path = o._cgroup_path;
      _mount_point = o._mount_point;
    }
    ~CgroupV1Controller() {
      // At least one subsystem controller exists with paths to malloc'd path
      // names
    }

    void set_subsystem_path(const char *cgroup_path);
    const char* subsystem_path() override { return _path; }
    bool is_read_only() override { return _read_only; }
    bool needs_hierarchy_adjustment() override;
};

class CgroupV1MemoryController final : public CgroupMemoryController {

  private:
    CgroupV1Controller _reader;
    CgroupV1Controller* reader() { return &_reader; }
  public:
    void set_subsystem_path(const char *cgroup_path) override {
      reader()->set_subsystem_path(cgroup_path);
    }
    jlong read_memory_limit_in_bytes(julong upper_bound) override;
    jlong memory_usage_in_bytes() override;
    jlong memory_and_swap_limit_in_bytes(julong host_mem, julong host_swap) override;
    jlong memory_and_swap_usage_in_bytes(julong host_mem, julong host_swap) override;
    jlong memory_soft_limit_in_bytes(julong upper_bound) override;
    jlong memory_max_usage_in_bytes() override;
    jlong rss_usage_in_bytes() override;
    jlong cache_usage_in_bytes() override;
    jlong kernel_memory_usage_in_bytes();
    jlong kernel_memory_limit_in_bytes(julong host_mem);
    jlong kernel_memory_max_usage_in_bytes();
    void print_version_specific_info(outputStream* st, julong host_mem) override;
    bool needs_hierarchy_adjustment() override {
      return reader()->needs_hierarchy_adjustment();
    }
    bool is_read_only() override {
      return reader()->is_read_only();
    }
    const char* subsystem_path() override { return reader()->subsystem_path(); }
    const char* mount_point() override { return reader()->mount_point(); }
    const char* cgroup_path() override { return reader()->cgroup_path(); }
  private:
    jlong read_mem_swappiness();
    jlong read_mem_swap(julong host_total_memsw);

  public:
    CgroupV1MemoryController(const CgroupV1Controller& reader)
      : _reader(reader) {
    }

};

class CgroupV1CpuController final : public CgroupCpuController {

  private:
    CgroupV1Controller _reader;
    CgroupV1Controller* reader() { return &_reader; }
  public:
    int cpu_quota() override;
    int cpu_period() override;
    int cpu_shares() override;
    void set_subsystem_path(const char *cgroup_path) override {
      reader()->set_subsystem_path(cgroup_path);
    }
    bool is_read_only() override {
      return reader()->is_read_only();
    }
    const char* subsystem_path() override {
      return reader()->subsystem_path();
    }
    const char* mount_point() override {
      return reader()->mount_point();
    }
    bool needs_hierarchy_adjustment() override {
      return reader()->needs_hierarchy_adjustment();
    }
    const char* cgroup_path() override { return reader()->cgroup_path(); }

  public:
    CgroupV1CpuController(const CgroupV1Controller& reader) : _reader(reader) {
    }
};

class CgroupV1Subsystem: public CgroupSubsystem {

  public:
    CgroupV1Subsystem(CgroupV1Controller* cpuset,
                      CgroupV1CpuController* cpu,
                      CgroupV1Controller* cpuacct,
                      CgroupV1Controller* pids,
                      CgroupV1MemoryController* memory);

    jlong kernel_memory_usage_in_bytes();
    jlong kernel_memory_limit_in_bytes();
    jlong kernel_memory_max_usage_in_bytes();

    char * cpu_cpuset_cpus();
    char * cpu_cpuset_memory_nodes();

    jlong pids_max();
    jlong pids_current();
    bool is_containerized();

    const char * container_type() {
      return "cgroupv1";
    }
    CachingCgroupController<CgroupMemoryController>* memory_controller() { return _memory; }
    CachingCgroupController<CgroupCpuController>* cpu_controller() { return _cpu; }

  private:
    /* controllers */
    CachingCgroupController<CgroupMemoryController>* _memory = nullptr;
    CgroupV1Controller* _cpuset = nullptr;
    CachingCgroupController<CgroupCpuController>* _cpu = nullptr;
    CgroupV1Controller* _cpuacct = nullptr;
    CgroupV1Controller* _pids = nullptr;

};

#endif // CGROUP_V1_SUBSYSTEM_LINUX_HPP