msr.h

/*
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are permitted provided that the following conditions are met:

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this list of conditions and the following disclaimer in the documentation and/or
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    * Neither the name of Intel Corporation nor the names of its contributors
may be used to endorse or promote products derived from this software without
specific prior written permission.

THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
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(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
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*/
// written by Roman Dementiev
//            Austen Ott

#ifndef CPUCounters_MSR_H
#define CPUCounters_MSR_H

/*!     \file msr.h
        \brief Low level interface to access hardware model specific registers

        Implemented and tested for Linux and 64-bit Windows 7
*/

#include "types.h"

#ifdef _MSC_VER
#include "windows.h"
#elif __APPLE__
#include <MSRAccessor.h>
#endif

#include <memory>
#include "mutex.h"

class MsrHandle {
#ifdef _MSC_VER
  HANDLE hDriver;
#elif __APPLE__
  static MSRAccessor *driver;
  static int num_handles;
#else
  int32 fd;
#endif
  uint32 cpu_id;
  MsrHandle();                              // forbidden
  MsrHandle(const MsrHandle &);             // forbidden
  MsrHandle &operator=(const MsrHandle &);  // forbidden

 public:
  MsrHandle(uint32 cpu);
  int32 read(uint64 msr_number, uint64 *value);
  int32 write(uint64 msr_number, uint64 value);
  int32 getCoreId() { return (int32)cpu_id; }
#ifdef __APPLE__
  int32 buildTopology(uint32 num_cores, void *);
  uint32 getNumInstances();
  uint32 incrementNumInstances();
  uint32 decrementNumInstances();
#endif
  virtual ~MsrHandle();
};

class SafeMsrHandle {
  std::shared_ptr<MsrHandle> pHandle;
  PCM_Util::Mutex mutex;

  SafeMsrHandle(const SafeMsrHandle &);             // forbidden
  SafeMsrHandle &operator=(const SafeMsrHandle &);  // forbidden

 public:
  SafeMsrHandle() {}

  SafeMsrHandle(uint32 core_id) : pHandle(new MsrHandle(core_id)) {}

  int32 read(uint64 msr_number, uint64 *value) {
    if (pHandle) return pHandle->read(msr_number, value);

    *value = 0;

    return (int32)sizeof(uint64);
  }

  int32 write(uint64 msr_number, uint64 value) {
    if (pHandle) return pHandle->write(msr_number, value);

    return (int32)sizeof(uint64);
  }
  int32 getCoreId() {
    if (pHandle) return pHandle->getCoreId();

    std::abort();
    return -1;
  }

  void lock() { mutex.lock(); }

  void unlock() { mutex.unlock(); }

#ifdef __APPLE__
  int32 buildTopology(uint32 num_cores, void *p) {
    if (pHandle) return pHandle->buildTopology(num_cores, p);

    std::abort();
    return 0;
  }
  uint32 getNumInstances() {
    if (pHandle) return pHandle->getNumInstances();

    std::abort();
    return 0;
  }
  uint32 incrementNumInstances() {
    if (pHandle) return pHandle->incrementNumInstances();

    std::abort();
    return 0;
  }
  uint32 decrementNumInstances() {
    if (pHandle) return pHandle->decrementNumInstances();

    std::abort();
    return 0;
  }
#endif
  virtual ~SafeMsrHandle() {}
};

#endif