ticks_os.h

 /*
 * Copyright (c) 2011 Mellanox Technologies Ltd.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without modification,
 * are permitted provided that the following conditions are met:
 *
 * 1. Redistributions of source code must retain the above copyright notice,
 *    this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright notice,
 *    this list of conditions and the following disclaimer in the documentation
 *    and/or other materials provided with the distribution.
 * 3. Neither the name of the Mellanox Technologies Ltd 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 AUTHOR ``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 AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
 * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
 * OF SUCH DAMAGE.
 *
 */
/**
 * @file ticks_os.h
 *
 *
 * @details: Base functions taken from ticks.h in favor of Windows compatibility,
 * using QueryPerformanceFrequency() and QueryPerformanceCounter() for max accuracy.
 *
 *
 * @author  Meny Yossefi <menyy@mellanox.com> 
 *
 **/
#ifndef _TICKS_OS_H_
#define _TICKS_OS_H_

#include <time.h>		/* clock_gettime()*/
#include <exception>
#include <stdint.h>// for int64_t
#include <stdlib.h>// for qsort
#include "clock.h"

typedef int64_t ticks_t;

#ifdef WIN32

#include <WinSock2.h>
#include <Winbase.h>

#pragma warning( disable : 4290 ) //exception specification ignored except to indicate a function is not __declspec(nothrow)
#pragma warning( disable : 4996 ) //The compiler encountered a function that was marked with deprecated.

#define		usleep(x)			Sleep (x/1000)
#define		snprintf			_snprintf

 struct timespec
  {
    time_t		tv_sec;			//Seconds.
    long int	tv_nsec;		//Nanoseconds.
 };

#endif

/**
 * RDTSC extensions
 */
#define TSCVAL_INITIALIZER	(0)

static const int64_t NSEC_IN_SEC  = 1000*1000*1000;
//Utility function
inline ticks_t timespec2nsec(const struct timespec &_val) { return NSEC_IN_SEC*_val.tv_sec + _val.tv_nsec; }

inline ticks_t os_gettimeoftsc()
{
#ifdef WIN32
		LARGE_INTEGER lp;
		double PCFreq = 0.0;
		QueryPerformanceFrequency(&lp);
		PCFreq = (double(lp.QuadPart))/(double)NSEC_IN_SEC; // NanoSec
		QueryPerformanceCounter(&lp);
		lp.QuadPart = (LONGLONG) ((lp.QuadPart) / (PCFreq));
		return (ticks_t)(lp.QuadPart);
#else
	register uint32_t upper_32, lower_32;

#if defined (__powerpc64__)
	unsigned long long ret;
	asm volatile ("mftb %0" : "=r" (ret) : );
	return (ticks_t)ret;
#elif defined(__arm__) || defined(__aarch64__)
	// so the compiler will not complain. for
	// arm compile, this inline is not used 
	// since no rdtsc supported on most arm processors
	upper_32 = lower_32 = 0;
	/*throw("rdtsc not supported in arm");*/
#else
	// ReaD Time Stamp Counter (RDTCS)
	__asm__ __volatile__("rdtsc" : "=a" (lower_32), "=d" (upper_32));
#endif
	// Return to user
	return (((ticks_t)upper_32) << 32) | lower_32;
#endif
}

inline void os_ts_gettimeofclock(struct timespec *pts)   {
#ifdef WIN32
	ticks_t val = os_gettimeoftsc();  // probably just NSEC_IN_SEC
	pts->tv_sec = val / NSEC_IN_SEC;
	pts->tv_nsec = val % NSEC_IN_SEC;
#else

	if (clock_gettime(CLOCK_MONOTONIC, pts)) {
		throw("clock_gettime failed");
	}
#endif
}

inline ticks_t os_gettimeofclock()   {
	struct timespec ts;
	os_ts_gettimeofclock(&ts);
	return timespec2nsec(ts);
}

#endif /*_TICKS_OS_H_*/