112 lines
2.5 KiB
C++
112 lines
2.5 KiB
C++
// Copyright 2009-2021 Intel Corporation
|
|
// SPDX-License-Identifier: Apache-2.0
|
|
|
|
#pragma once
|
|
|
|
#include "intrinsics.h"
|
|
#include "sysinfo.h"
|
|
#include "atomic.h"
|
|
|
|
namespace embree
|
|
{
|
|
/*! system barrier using operating system */
|
|
class BarrierSys
|
|
{
|
|
public:
|
|
|
|
/*! construction / destruction */
|
|
BarrierSys (size_t N = 0);
|
|
~BarrierSys ();
|
|
|
|
private:
|
|
/*! class in non-copyable */
|
|
BarrierSys (const BarrierSys& other) DELETED; // do not implement
|
|
BarrierSys& operator= (const BarrierSys& other) DELETED; // do not implement
|
|
|
|
public:
|
|
/*! initializes the barrier with some number of threads */
|
|
void init(size_t count);
|
|
|
|
/*! lets calling thread wait in barrier */
|
|
void wait();
|
|
|
|
private:
|
|
void* opaque;
|
|
};
|
|
|
|
/*! fast active barrier using atomic counter */
|
|
struct BarrierActive
|
|
{
|
|
public:
|
|
BarrierActive ()
|
|
: cntr(0) {}
|
|
|
|
void reset() {
|
|
cntr.store(0);
|
|
}
|
|
|
|
void wait (size_t numThreads)
|
|
{
|
|
cntr++;
|
|
while (cntr.load() != numThreads)
|
|
pause_cpu();
|
|
}
|
|
|
|
private:
|
|
std::atomic<size_t> cntr;
|
|
};
|
|
|
|
/*! fast active barrier that does not require initialization to some number of threads */
|
|
struct BarrierActiveAutoReset
|
|
{
|
|
public:
|
|
BarrierActiveAutoReset ()
|
|
: cntr0(0), cntr1(0) {}
|
|
|
|
void wait (size_t threadCount)
|
|
{
|
|
cntr0.fetch_add(1);
|
|
while (cntr0 != threadCount) pause_cpu();
|
|
cntr1.fetch_add(1);
|
|
while (cntr1 != threadCount) pause_cpu();
|
|
cntr0.fetch_add(-1);
|
|
while (cntr0 != 0) pause_cpu();
|
|
cntr1.fetch_add(-1);
|
|
while (cntr1 != 0) pause_cpu();
|
|
}
|
|
|
|
private:
|
|
std::atomic<size_t> cntr0;
|
|
std::atomic<size_t> cntr1;
|
|
};
|
|
|
|
class LinearBarrierActive
|
|
{
|
|
public:
|
|
|
|
/*! construction and destruction */
|
|
LinearBarrierActive (size_t threadCount = 0);
|
|
~LinearBarrierActive();
|
|
|
|
private:
|
|
/*! class in non-copyable */
|
|
LinearBarrierActive (const LinearBarrierActive& other) DELETED; // do not implement
|
|
LinearBarrierActive& operator= (const LinearBarrierActive& other) DELETED; // do not implement
|
|
|
|
public:
|
|
/*! initializes the barrier with some number of threads */
|
|
void init(size_t threadCount);
|
|
|
|
/*! thread with threadIndex waits in the barrier */
|
|
void wait (const size_t threadIndex);
|
|
|
|
private:
|
|
volatile unsigned char* count0;
|
|
volatile unsigned char* count1;
|
|
volatile unsigned int mode;
|
|
volatile unsigned int flag0;
|
|
volatile unsigned int flag1;
|
|
volatile size_t threadCount;
|
|
};
|
|
}
|
|
|