3_priority_init.h

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#include "gts/platform/Thread.h"
 
#include "gts/micro_scheduler/WorkerPool.h"
#include "gts/micro_scheduler/MicroScheduler.h"
 
using namespace gts;
 
namespace gts_examples {
 
void priorityInit()
{
    printf ("================\n");
    printf ("priorityInit\n");
    printf ("================\n");
 
    // The GTS micro-schedule implements task priorities, yet it does not
    // context switch when a higher priority task is spawned. To achieve
    // context switching behavior, one needs to use the OS's preemptive scheduler.
 
    // Let's say we need two priorities hi and low.
    constexpr uint32_t PRIORITY_COUNT = 2;
    WorkerPool workerPool[PRIORITY_COUNT];
    MicroScheduler microScheduler[PRIORITY_COUNT];
 
    // For each priority, build a pool with a different priority and attach
    // a scheduler to it.
    for (uint32_t iPriority = 0; iPriority < PRIORITY_COUNT; ++iPriority)
    {
        WorkerPoolDesc workerPoolDesc;
 
        for (uint32_t iWorker = 0; iWorker < Thread::getHardwareThreadCount(); iWorker++)
        {
            WorkerThreadDesc workerDesc;
            workerDesc.priority = (Thread::Priority)((uint32_t)Thread::Priority::PRIORITY_NORMAL + iPriority);
            workerPoolDesc.workerDescs.push_back(workerDesc);
        }
 
        workerPool[iPriority].initialize(workerPoolDesc);
        microScheduler[iPriority].initialize(&workerPool[iPriority]);
    }
 
    // Task submitted from microScheduler[1] running on threads from
    // workerPool[1] will preempt any running tasks from microScheduler[0].
}
 
} // namespace gts_examples