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UnrealEngine/Engine/Source/ThirdParty/Intel/Embree/embree-4.3.3/common/tasking/taskschedulertbb.cpp
2025-05-18 13:04:45 +08:00

92 lines
2.5 KiB
C++

// Copyright 2009-2021 Intel Corporation
// SPDX-License-Identifier: Apache-2.0
#include "taskschedulertbb.h"
namespace embree
{
static bool g_tbb_threads_initialized = false;
#if TBB_INTERFACE_VERSION >= 11005
static tbb::global_control* g_tbb_thread_control = nullptr;
#else
static tbb::task_scheduler_init g_tbb_threads(tbb::task_scheduler_init::deferred);
#endif
class TBBAffinity: public tbb::task_scheduler_observer
{
public:
void on_scheduler_entry( bool ) {
setAffinity(TaskScheduler::threadIndex());
}
} tbb_affinity;
void TaskScheduler::create(size_t numThreads, bool set_affinity, bool start_threads)
{
assert(numThreads);
/* first terminate threads in case we configured them */
if (g_tbb_threads_initialized) {
#if TBB_INTERFACE_VERSION >= 11005
delete g_tbb_thread_control;
g_tbb_thread_control = nullptr;
#else
g_tbb_threads.terminate();
#endif
g_tbb_threads_initialized = false;
}
/* only set affinity if requested by the user */
#if TBB_INTERFACE_VERSION >= 9000 // affinity not properly supported by older TBB versions
if (set_affinity)
tbb_affinity.observe(true);
#endif
/* now either keep default settings or configure number of threads */
if (numThreads == std::numeric_limits<size_t>::max()) {
numThreads = threadCount();
}
else {
g_tbb_threads_initialized = true;
const size_t max_concurrency = threadCount();
if (numThreads > max_concurrency) numThreads = max_concurrency;
#if TBB_INTERFACE_VERSION >= 11005
g_tbb_thread_control = new tbb::global_control(tbb::global_control::max_allowed_parallelism,numThreads);
#else
g_tbb_threads.initialize(int(numThreads));
#endif
}
/* start worker threads */
if (start_threads)
{
BarrierSys barrier(numThreads);
tbb::parallel_for(size_t(0), size_t(numThreads), size_t(1), [&] ( size_t i ) {
barrier.wait();
});
}
}
void TaskScheduler::destroy()
{
#if TBB_INTERFACE_VERSION >= 9000 // affinity not properly supported by older TBB versions
// Stop observe to prevent calling on_scheduler_entry
// when static objects are already destroyed.
if (tbb_affinity.is_observing())
tbb_affinity.observe(false);
#endif
if (g_tbb_threads_initialized) {
#if TBB_INTERFACE_VERSION >= 11005
delete g_tbb_thread_control;
g_tbb_thread_control = nullptr;
#else
g_tbb_threads.terminate();
#endif
g_tbb_threads_initialized = false;
}
}
}