Scheduler.h

/*
 * Copyright (c) 2008-2014, Pedigree Developers
 *
 * Please see the CONTRIB file in the root of the source tree for a full
 * list of contributors.
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

#ifndef SCHEDULER_H
#define SCHEDULER_H

#include "pedigree/kernel/Atomic.h"
#include "pedigree/kernel/Spinlock.h"
#include "pedigree/kernel/compiler.h"
#include "pedigree/kernel/processor/types.h"
#include "pedigree/kernel/utilities/List.h"
#include "pedigree/kernel/utilities/Tree.h"
#include "pedigree/kernel/utilities/new"

class Thread;
class Process;
class PerProcessorScheduler;

class EXPORTED_PUBLIC Scheduler
{
  public:
    static Scheduler &instance()
    {
        return m_Instance;
    }

#ifdef THREADS

    bool initialise(Process *pKernelProcess);

    void addThread(Thread *pThread, PerProcessorScheduler &PPSched);
    void removeThread(Thread *pThread);

    bool threadInSchedule(Thread *pThread);

    size_t addProcess(Process *pProcess);
    void removeProcess(Process *pProcess);
#endif  // THREADS

    void yield();

    size_t getNumProcesses();

#ifdef THREADS

    Process *getProcess(size_t n);

    void threadStatusChanged(Thread *pThread);

    Process *getKernelProcess() const
    {
        return m_pKernelProcess;
    }

    PerProcessorScheduler *getBootstrapProcessorScheduler() const
    {
        return m_pBspScheduler;
    }
#endif  // THREADS

  private:
    Scheduler();
    NOT_COPYABLE_OR_ASSIGNABLE(Scheduler);

    static Scheduler m_Instance;

#ifdef THREADS

    List<Process *, 0> m_Processes;

    Atomic<size_t> m_NextPid;

    Tree<PerProcessorScheduler *, List<Thread *> *> m_PTMap;

    Tree<Thread *, PerProcessorScheduler *> m_TPMap;

    Process *m_pKernelProcess;

    PerProcessorScheduler *m_pBspScheduler;

    Spinlock m_SchedulerLock;
#endif  // THREADS
};

#endif  // SCHEDULER_H