// $Id$
//
// Copyright (C) 2006
-// Fraunhofer Institut fuer offene Kommunikationssysteme (FOKUS)
-// Kompetenzzentrum fuer Satelitenkommunikation (SatCom)
-// Stefan Bund <stefan.bund@fokus.fraunhofer.de>
+// Fraunhofer Institute for Open Communication Systems (FOKUS)
+// Competence Center NETwork research (NET), St. Augustin, GERMANY
+// Stefan Bund <g0dil@berlios.de>
//
// This program is free software; you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
/** \file
\brief Scheduler non-inline non-template implementation
- \idea Implement signal handling (See source for more discussion
- about this)
-
\idea Multithreading support: To support multithreading, the
static member Scheduler::instance() must return a thread-local
value (that is Scheduler::instance() must allocate one Scheduler
threads)
*/
-// Here a basic concept of how to add signal support to the scheduler:
-//
-// ... no, I had overlooked one race condition. So back to the signal-pipe approach ...
-
#include "Scheduler.hh"
//#include "Scheduler.ih"
// Custom includes
-#include <errno.h>
-#include <sys/epoll.h>
-#include <unistd.h>
-#include <fcntl.h>
-#include "../Utils/Exception.hh"
-
-static const int EPollInitialSize = 16;
#define prefix_
///////////////////////////////cc.p////////////////////////////////////////
-prefix_ senf::Scheduler::Scheduler()
- : files_(0), timerIdCounter_(0), epollFd_ (epoll_create(EPollInitialSize)), terminate_(false),
- eventTime_(0), eventEarly_(ClockService::milliseconds(11)), eventAdjust_(0)
-{
- if (epollFd_<0)
- throw SystemException(errno);
-
- if (::pipe(sigpipe_) < 0)
- throw SystemException(errno);
-
- int flags (::fcntl(sigpipe_[1],F_GETFL));
- if (flags < 0)
- throw SystemException(errno);
- flags |= O_NONBLOCK;
- if (::fcntl(sigpipe_[1], F_SETFL, flags) < 0)
- throw SystemException(errno);
-
- ::epoll_event ev;
- ::memset(&ev, 0, sizeof(ev));
- ev.events = EV_READ;
- ev.data.fd = sigpipe_[0];
- if (::epoll_ctl(epollFd_, EPOLL_CTL_ADD, sigpipe_[0], &ev) < 0)
- throw SystemException(errno);
+namespace {
+ bool terminate_ (false);
+ bool running_ (false);
}
-prefix_ void senf::Scheduler::registerSignal(unsigned signal, SimpleCallback const & cb)
+prefix_ void senf::scheduler::terminate()
{
- ::sigset_t sig;
- ::sigemptyset(&sig);
- if (::sigaddset(&sig, signal) < 0)
- throw InvalidSignalNumberException();
- ::sigprocmask(SIG_BLOCK, &sig, 0);
- ::sigaddset(&sigset_, signal);
- if (sigHandlers_.size() <= signal)
- sigHandlers_.resize(signal+1);
- sigHandlers_[signal] = cb;
-
- registerSigHandlers();
+ terminate_ = true;
}
-prefix_ void senf::Scheduler::unregisterSignal(unsigned signal)
+prefix_ void senf::scheduler::yield()
{
- if (::sigdelset(&sigset_, signal) < 0)
- throw InvalidSignalNumberException();
- sigHandlers_[signal] = 0;
- ::signal(signal, SIG_DFL);
- registerSigHandlers();
+ senf::scheduler::detail::FIFORunner::instance().yield();
}
-prefix_ void senf::Scheduler::do_add(int fd, FdCallback const & cb, int eventMask)
+prefix_ bool senf::scheduler::running()
{
- if (eventMask == 0)
- return;
-
- FdTable::iterator i (fdTable_.find(fd));
- int action (EPOLL_CTL_MOD);
- if (i == fdTable_.end()) {
- action = EPOLL_CTL_ADD;
- i = fdTable_.insert(std::make_pair(fd, EventSpec())).first;
- }
- if (i->second.epollMask() == 0) {
- action = EPOLL_CTL_ADD;
- fdErase_.erase( std::remove(fdErase_.begin(), fdErase_.end(), unsigned(fd)),
- fdErase_.end() );
- }
-
- if (eventMask & EV_READ) i->second.cb_read = cb;
- if (eventMask & EV_PRIO) i->second.cb_prio = cb;
- if (eventMask & EV_WRITE) i->second.cb_write = cb;
-
- epoll_event ev;
- memset(&ev,0,sizeof(ev));
- ev.events = i->second.epollMask();
- ev.data.fd = fd;
-
- if (! i->second.file && epoll_ctl(epollFd_, action, fd, &ev) < 0) {
- if (errno == EPERM) {
- // Argh ... epoll does not support ordinary files :-( :-(
- i->second.file = true;
- ++ files_;
- }
- else
- throwErrno("::epoll_ctl()");
- }
+ return running_;
}
-prefix_ void senf::Scheduler::do_remove(int fd, int eventMask)
+prefix_ senf::ClockService::clock_type senf::scheduler::now()
{
- if (eventMask == 0)
- return;
-
- FdTable::iterator i (fdTable_.find(fd));
- if (i == fdTable_.end())
- return;
-
- if (eventMask & EV_READ) i->second.cb_read = 0;
- if (eventMask & EV_PRIO) i->second.cb_prio = 0;
- if (eventMask & EV_WRITE) i->second.cb_write = 0;
-
- epoll_event ev;
- memset(&ev,0,sizeof(ev));
- ev.events = i->second.epollMask();
- ev.data.fd = fd;
+ return running() ? eventTime() : ClockService::now();
+}
- int action (EPOLL_CTL_MOD);
- bool file (i->second.file);
- if (ev.events==0) {
- action = EPOLL_CTL_DEL;
- fdErase_.push_back(fd);
- }
+namespace {
+
+ // We don't want try { } catch(...) { ... throw; } since that will make debugging more
+ // difficult: the stack backtrace for an unexpected exception would always end here.
+ struct SchedulerScopedInit
+ {
+ SchedulerScopedInit()
+ {
+ senf::scheduler::detail::FIFORunner::instance().startWatchdog();
+ senf::scheduler::detail::SignalDispatcher::instance().unblockSignals();
+ senf::scheduler::detail::TimerDispatcher::instance().enable();
+ running_ = true;
+ }
- if (! file && epoll_ctl(epollFd_, action, fd, &ev) < 0)
- throwErrno("::epoll_ctl()");
- if (file)
- -- files_;
+ ~SchedulerScopedInit()
+ {
+ senf::scheduler::detail::TimerDispatcher::instance().disable();
+ senf::scheduler::detail::SignalDispatcher::instance().blockSignals();
+ senf::scheduler::detail::FIFORunner::instance().stopWatchdog();
+ running_ = false;
+ }
+ };
}
-prefix_ void senf::Scheduler::registerSigHandlers()
+prefix_ void senf::scheduler::process()
{
- for (unsigned signal (1); signal < sigHandlers_.size(); ++signal) {
- if (sigHandlers_[signal]) {
- struct ::sigaction sa;
- sa.sa_sigaction = & Scheduler::sigHandler;
- sa.sa_mask = sigset_;
- sa.sa_flags = SA_SIGINFO;
- if (signal == SIGCHLD)
- sa.sa_flags |= SA_NOCLDSTOP;
- if (::sigaction(signal, &sa, 0) < 0)
- throw SystemException(errno);
- }
+ SchedulerScopedInit initScheduler;
+ terminate_ = false;
+ running_ = true;
+ detail::TimerDispatcher::instance().reschedule();
+ while(! terminate_ && ! (detail::FdDispatcher::instance().empty() &&
+ detail::TimerDispatcher::instance().empty() &&
+ detail::FileDispatcher::instance().empty())) {
+ detail::FdManager::instance().processOnce();
+ detail::FileDispatcher::instance().prepareRun();
+ detail::EventHookDispatcher::instance().prepareRun();
+ detail::TimerDispatcher::instance().prepareRun();
+ detail::FIFORunner::instance().run();
+ detail::TimerDispatcher::instance().reschedule();
}
}
-prefix_ void senf::Scheduler::sigHandler(int signal, ::siginfo_t * siginfo, void *)
+prefix_ void senf::scheduler::restart()
{
- // This is a bit unsafe. Better write single bytes and place the siginfo into an explicit
- // queue. Since signals are only unblocked during epoll_wait, we even wouldn't need to
- // synchronize access to that queue any further.
-
- ::write(instance().sigpipe_[1], siginfo, sizeof(*siginfo));
-
- // We ignore errors. The file handle is set to non-blocking IO. If any failure occurs (pipe
- // full), the signal will be dropped. That's like kernel signal handling which may also drop
- // signals.
+ detail::FdManager* fdm (&detail::FdManager::instance());
+ detail::FIFORunner* ffr (&detail::FIFORunner::instance());
+ detail::FdDispatcher* fdd (&detail::FdDispatcher::instance());
+ detail::TimerDispatcher* tdd (&detail::TimerDispatcher::instance());
+ detail::SignalDispatcher* sdd (&detail::SignalDispatcher::instance());
+ detail::FileDispatcher* fld (&detail::FileDispatcher::instance());
+ detail::EventHookDispatcher* eed (&detail::EventHookDispatcher::instance());
+
+ eed->~EventHookDispatcher();
+ fld->~FileDispatcher();
+ sdd->~SignalDispatcher();
+ tdd->~TimerDispatcher();
+ fdd->~FdDispatcher();
+ ffr->~FIFORunner();
+ fdm->~FdManager();
+
+ new (fdm) detail::FdManager();
+ new (ffr) detail::FIFORunner();
+ new (fdd) detail::FdDispatcher();
+ new (tdd) detail::TimerDispatcher();
+ new (sdd) detail::SignalDispatcher();
+ new (fld) detail::FileDispatcher();
+ new (eed) detail::EventHookDispatcher();
}
-prefix_ int senf::Scheduler::EventSpec::epollMask()
- const
+prefix_ bool senf::scheduler::empty()
{
- int mask (0);
- if (cb_read) mask |= EPOLLIN;
- if (cb_prio) mask |= EPOLLPRI;
- if (cb_write) mask |= EPOLLOUT;
- return mask;
+ return detail::FdDispatcher::instance().empty()
+ && detail::TimerDispatcher::instance().empty()
+ && detail::FileDispatcher::instance().empty()
+ && detail::SignalDispatcher::instance().empty()
+ && detail::EventHookDispatcher::instance().empty();
}
-prefix_ void senf::Scheduler::process()
+prefix_ void senf::scheduler::hiresTimers()
{
- terminate_ = false;
- eventTime_ = ClockService::now();
- while (! terminate_) {
-
- // Since a callback may have disabled further timers, we need to check for canceled timeouts
- // again.
-
- while (! timerQueue_.empty()) {
- TimerMap::iterator i (timerQueue_.top());
- if (! i->second.canceled)
- break;
- timerMap_.erase(i);
- timerQueue_.pop();
- }
-
- for (FdEraseList::iterator i (fdErase_.begin()); i != fdErase_.end(); ++i)
- fdTable_.erase(*i);
- fdErase_.clear();
-
- int timeout (-1);
- if (files_ > 0)
- timeout = 0;
- else {
- if (timerQueue_.empty()) {
- if (fdTable_.empty())
- break;
- }
- else {
- ClockService::clock_type delta (
- (timerQueue_.top()->second.timeout - eventTime_ + eventAdjust_)/1000000UL);
- timeout = delta < 0 ? 0 : delta;
- }
- }
-
- ///\todo Handle more than one epoll_event per call
- struct epoll_event ev;
-
- ::sigprocmask(SIG_UNBLOCK, &sigset_, 0);
- int events (epoll_wait(epollFd_, &ev, 1, timeout));
- ::sigprocmask(SIG_BLOCK, &sigset_, 0);
-
- if (events<0)
- if (errno != EINTR)
- throw SystemException(errno);
-
- eventTime_ = ClockService::now();
-
- // We always run timeout handlers. This is important, even if a file-descriptor is signaled
- // since some descriptors (e.g. real files) will *always* be ready and we still may want to
- // handle timers. Time handlers are run before file events to not delay them unnecessarily.
-
- while (! timerQueue_.empty()) {
- TimerMap::iterator i (timerQueue_.top());
- if (i->second.canceled)
- ;
- else if (i->second.timeout <= eventTime_ + eventEarly_)
- i->second.cb();
- else
- break;
- timerQueue_.pop();
- timerMap_.erase(i);
- }
-
- // Check the signal queue
- if (events > 0 && ev.data.fd == sigpipe_[0]) {
- ::siginfo_t siginfo;
- if (::read(sigpipe_[0], &siginfo, sizeof(siginfo)) < int(sizeof(siginfo))) {
- // We ignore truncated records which may only occur if the signal
- // queue became filled up
- SENF_LOG((senf::log::IMPORTANT)("Truncated signal record!"));
- continue;
- }
- if (siginfo.si_signo < int(sigHandlers_.size()) && sigHandlers_[siginfo.si_signo])
- sigHandlers_[siginfo.si_signo]();
- continue;
- }
+#ifdef HAVE_TIMERFD
+ if (haveScalableHiresTimers())
+ detail::TimerDispatcher::instance().timerSource(
+ std::auto_ptr<detail::TimerSource>(new detail::TimerFDTimerSource()));
+ else
+#endif
+ detail::TimerDispatcher::instance().timerSource(
+ std::auto_ptr<detail::TimerSource>(new detail::POSIXTimerSource()));
+}
- for (FdTable::iterator i = fdTable_.begin(); i != fdTable_.end(); ++i) {
- EventSpec & spec (i->second);
+///////////////////////////////////////////////////////////////////////////
+// senf::schedulerLogTimeSource
- if (! (spec.file || (events > 0 && i->first == ev.data.fd)))
- continue;
-
- unsigned extraFlags (0);
- unsigned mask (spec.file ? spec.epollMask() : ev.events);
+prefix_ senf::log::time_type senf::scheduler::LogTimeSource::operator()()
+ const
+{
+ return eventTime();
+}
- if (mask & EPOLLHUP) extraFlags |= EV_HUP;
- if (mask & EPOLLERR) extraFlags |= EV_ERR;
+///////////////////////////////////////////////////////////////////////////
+// senf::scheduler::BlockSignals
- if (mask & EPOLLIN) {
- BOOST_ASSERT(spec.cb_read);
- spec.cb_read(EventId(EV_READ | extraFlags));
- }
- else if (mask & EPOLLPRI) {
- BOOST_ASSERT(spec.cb_prio);
- spec.cb_prio(EventId(EV_PRIO | extraFlags));
- }
- else if (mask & EPOLLOUT) {
- BOOST_ASSERT(spec.cb_write);
- spec.cb_write(EventId(EV_WRITE | extraFlags));
- }
- else {
- // This branch is only taken, if HUP or ERR is signaled but none of IN/OUT/PRI.
- // In this case we will signal all registered callbacks. The callbacks must be
- // prepared to be called multiple times if they are registered to more than
- // one event.
- if (spec.cb_write)
- spec.cb_write(EventId(extraFlags));
- if (spec.cb_prio)
- spec.cb_prio(EventId(extraFlags));
- if (spec.cb_read)
- spec.cb_read(EventId(extraFlags));
- }
- }
- }
+prefix_ senf::scheduler::BlockSignals::BlockSignals(bool initiallyBlocked)
+ : blocked_ (false)
+{
+ ::sigfillset(&allSigs_);
+ if (initiallyBlocked)
+ block();
}
-///////////////////////////////////////////////////////////////////////////
-// senf::SchedulerLogTimeSource
+prefix_ void senf::scheduler::BlockSignals::block()
+{
+ if (blocked_)
+ return;
+ ::sigprocmask(SIG_BLOCK, &allSigs_, &savedSigs_);
+ blocked_ = true;
+}
-prefix_ boost::posix_time::ptime senf::SchedulerLogTimeSource::operator()()
- const
+prefix_ void senf::scheduler::BlockSignals::unblock()
{
- return ClockService::abstime(Scheduler::instance().eventTime());
+ if (!blocked_)
+ return;
+ ::sigprocmask(SIG_SETMASK, &savedSigs_, 0);
+ blocked_ = false;
}
///////////////////////////////cc.e////////////////////////////////////////
projects / senf.git / blobdiff