osrm-backend/include/engine/data_watchdog.hpp

91 lines
2.6 KiB
C++

#ifndef OSRM_ENGINE_DATA_WATCHDOG_HPP
#define OSRM_ENGINE_DATA_WATCHDOG_HPP
#include "engine/datafacade/contiguous_internalmem_datafacade.hpp"
#include "engine/datafacade/shared_memory_allocator.hpp"
#include "storage/shared_barrier.hpp"
#include "storage/shared_datatype.hpp"
#include "storage/shared_memory.hpp"
#include <boost/interprocess/sync/named_upgradable_mutex.hpp>
#include <boost/thread/lock_types.hpp>
#include <boost/thread/locks.hpp>
#include <boost/thread/shared_mutex.hpp>
#include <memory>
#include <thread>
namespace osrm
{
namespace engine
{
// This class monitors the shared memory region that contains the pointers to
// the data and layout regions that should be used. This region is updated
// once a new dataset arrives.
class DataWatchdog
{
public:
DataWatchdog() : barrier(boost::interprocess::open_only), active(true), timestamp(0)
{
// create the initial facade before launching the watchdog thread
{
boost::interprocess::scoped_lock<storage::SharedBarrier::mutex_type>
current_region_lock(barrier.GetMutex());
facade = std::make_shared<datafacade::ContiguousInternalMemoryDataFacade>(
std::make_unique<datafacade::SharedMemoryAllocator>(barrier.GetRegion()));
timestamp = barrier.GetTimestamp();
}
watcher = std::thread(&DataWatchdog::Run, this);
}
~DataWatchdog()
{
active = false;
barrier.NotifyAll();
watcher.join();
}
auto GetDataFacade() const { return facade; }
private:
void Run()
{
while (active)
{
boost::interprocess::scoped_lock<storage::SharedBarrier::mutex_type>
current_region_lock(barrier.GetMutex());
while (active && timestamp == barrier.GetTimestamp())
{
barrier.Wait(current_region_lock);
}
if (timestamp != barrier.GetTimestamp())
{
facade = std::make_shared<datafacade::ContiguousInternalMemoryDataFacade>(
std::make_unique<datafacade::SharedMemoryAllocator>(barrier.GetRegion()));
timestamp = barrier.GetTimestamp();
util::Log() << "updated facade to region "
<< storage::regionToString(barrier.GetRegion()) << " with timestamp "
<< timestamp;
}
}
util::Log() << "DataWatchdog thread stopped";
}
storage::SharedBarrier barrier;
std::thread watcher;
bool active;
unsigned timestamp;
std::shared_ptr<datafacade::ContiguousInternalMemoryDataFacade> facade;
};
}
}
#endif