scheduler.hh revision 12953
112953Sgabeblack@google.com/*
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1312953Sgabeblack@google.com * this software without specific prior written permission.
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2612953Sgabeblack@google.com *
2712953Sgabeblack@google.com * Authors: Gabe Black
2812953Sgabeblack@google.com */
2912953Sgabeblack@google.com
3012953Sgabeblack@google.com#ifndef __SYSTEMC_CORE_SCHEDULER_HH__
3112953Sgabeblack@google.com#define __SYSTEMC_CORE_SCHEDULER_HH__
3212953Sgabeblack@google.com
3312953Sgabeblack@google.com#include "systemc/core/list.hh"
3412953Sgabeblack@google.com#include "systemc/core/process.hh"
3512953Sgabeblack@google.com
3612953Sgabeblack@google.comnamespace sc_gem5
3712953Sgabeblack@google.com{
3812953Sgabeblack@google.com
3912953Sgabeblack@google.comtypedef NodeList<Process> ProcessList;
4012953Sgabeblack@google.com
4112953Sgabeblack@google.comclass Scheduler
4212953Sgabeblack@google.com{
4312953Sgabeblack@google.com  public:
4412953Sgabeblack@google.com    Scheduler();
4512953Sgabeblack@google.com
4612953Sgabeblack@google.com    uint64_t numCycles() { return _numCycles; }
4712953Sgabeblack@google.com    Process *current() { return _current; }
4812953Sgabeblack@google.com
4912953Sgabeblack@google.com    // Run the initialization phase.
5012953Sgabeblack@google.com    void initialize();
5112953Sgabeblack@google.com
5212953Sgabeblack@google.com    // Run delta cycles until time needs to advance.
5312953Sgabeblack@google.com    void runCycles();
5412953Sgabeblack@google.com
5512953Sgabeblack@google.com    // Put a process on the list of processes to be initialized.
5612953Sgabeblack@google.com    void init(Process *p) { initList.pushLast(p); }
5712953Sgabeblack@google.com
5812953Sgabeblack@google.com    // Run the next process, if there is one.
5912953Sgabeblack@google.com    void yield();
6012953Sgabeblack@google.com
6112953Sgabeblack@google.com    // Put a process on the ready list.
6212953Sgabeblack@google.com    void
6312953Sgabeblack@google.com    ready(Process *p)
6412953Sgabeblack@google.com    {
6512953Sgabeblack@google.com        // Clump methods together to minimize context switching.
6612953Sgabeblack@google.com        if (p->procKind() == ::sc_core::SC_METHOD_PROC_)
6712953Sgabeblack@google.com            readyList.pushFirst(p);
6812953Sgabeblack@google.com        else
6912953Sgabeblack@google.com            readyList.pushLast(p);
7012953Sgabeblack@google.com    }
7112953Sgabeblack@google.com
7212953Sgabeblack@google.com    // Run the given process immediately, preempting whatever may be running.
7312953Sgabeblack@google.com    void
7412953Sgabeblack@google.com    runNow(Process *p)
7512953Sgabeblack@google.com    {
7612953Sgabeblack@google.com        // If a process is running, schedule it/us to run again.
7712953Sgabeblack@google.com        if (_current)
7812953Sgabeblack@google.com            readyList.pushFirst(_current);
7912953Sgabeblack@google.com        // Schedule p to run first.
8012953Sgabeblack@google.com        readyList.pushFirst(p);
8112953Sgabeblack@google.com        yield();
8212953Sgabeblack@google.com    }
8312953Sgabeblack@google.com
8412953Sgabeblack@google.com  private:
8512953Sgabeblack@google.com    uint64_t _numCycles;
8612953Sgabeblack@google.com
8712953Sgabeblack@google.com    Process *_current;
8812953Sgabeblack@google.com
8912953Sgabeblack@google.com    ProcessList initList;
9012953Sgabeblack@google.com    ProcessList readyList;
9112953Sgabeblack@google.com
9212953Sgabeblack@google.com    void evaluate();
9312953Sgabeblack@google.com    void update();
9412953Sgabeblack@google.com    void delta();
9512953Sgabeblack@google.com};
9612953Sgabeblack@google.com
9712953Sgabeblack@google.comextern Scheduler scheduler;
9812953Sgabeblack@google.com
9912953Sgabeblack@google.com} // namespace sc_gem5
10012953Sgabeblack@google.com
10112953Sgabeblack@google.com#endif // __SYSTEMC_CORE_SCHEDULER_H__
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