ParallelJobsGeneric.cpp [plain text]
#include "config.h"
#if ENABLE(PARALLEL_JOBS) && ENABLE(THREADING_GENERIC)
#include "ParallelJobs.h"
#include "UnusedParam.h"
#if OS(DARWIN) || OS(OPENBSD) || OS(NETBSD)
#include <sys/sysctl.h>
#include <sys/types.h>
#elif OS(LINUX) || OS(AIX) || OS(SOLARIS)
#include <unistd.h>
#elif OS(WINDOWS)
#include <Windows.h>
#endif
namespace WTF {
Vector< RefPtr<ParallelEnvironment::ThreadPrivate> >* ParallelEnvironment::s_threadPool = 0;
int ParallelEnvironment::s_maxNumberOfParallelThreads = -1;
void ParallelEnvironment::determineMaxNumberOfParallelThreads()
{
const int defaultIfUnavailable = 2;
#if OS(DARWIN) || OS(OPENBSD) || OS(NETBSD)
unsigned result;
size_t length = sizeof(result);
int name[] = {
CTL_HW,
HW_NCPU
};
int sysctlResult = sysctl(name, sizeof(name) / sizeof(int), &result, &length, 0, 0);
s_maxNumberOfParallelThreads = sysctlResult < 0 ? defaultIfUnavailable : result;
#elif OS(LINUX) || OS(AIX) || OS(SOLARIS)
long sysconfResult = sysconf(_SC_NPROCESSORS_ONLN);
s_maxNumberOfParallelThreads = sysconfResult < 0 ? defaultIfUnavailable : static_cast<int>(sysconfResult);
#elif OS(WINDOWS)
UNUSED_PARAM(defaultIfUnavailable);
SYSTEM_INFO sysInfo;
GetSystemInfo(&sysInfo);
s_maxNumberOfParallelThreads = sysInfo.dwNumberOfProcessors;
#else
s_maxNumberOfParallelThreads = defaultIfUnavailable;
#endif
}
bool ParallelEnvironment::ThreadPrivate::tryLockFor(ParallelEnvironment* parent)
{
bool locked = m_mutex.tryLock();
if (!locked)
return false;
if (m_parent) {
m_mutex.unlock();
return false;
}
if (!m_threadID)
m_threadID = createThread(&ParallelEnvironment::ThreadPrivate::workerThread, this, "Parallel worker");
if (m_threadID)
m_parent = parent;
m_mutex.unlock();
return m_threadID;
}
void ParallelEnvironment::ThreadPrivate::execute(ThreadFunction threadFunction, void* parameters)
{
MutexLocker lock(m_mutex);
m_threadFunction = threadFunction;
m_parameters = parameters;
m_running = true;
m_threadCondition.signal();
}
void ParallelEnvironment::ThreadPrivate::waitForFinish()
{
MutexLocker lock(m_mutex);
while (m_running)
m_threadCondition.wait(m_mutex);
}
void* ParallelEnvironment::ThreadPrivate::workerThread(void* threadData)
{
ThreadPrivate* sharedThread = reinterpret_cast<ThreadPrivate*>(threadData);
MutexLocker lock(sharedThread->m_mutex);
while (sharedThread->m_threadID) {
if (sharedThread->m_running) {
(*sharedThread->m_threadFunction)(sharedThread->m_parameters);
sharedThread->m_running = false;
sharedThread->m_parent = 0;
sharedThread->m_threadCondition.signal();
}
sharedThread->m_threadCondition.wait(sharedThread->m_mutex);
}
return 0;
}
}
#endif // ENABLE(PARALLEL_JOBS) && ENABLE(THREADING_GENERIC)