// $Id$
//
// 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:
-//
-// Every signal to be reported by the scheduler will be asigned a
-// generic signal handler by the scheduler. This signal handler will
-// use longjmp (juck) to report this signal back to the scheduler
-// main-loop.
-//
-// To make this safe, the main-loop will look something like:
-//
-// int signal = setjmp(jmpBuffer_);
-// if (signal == 0) {
-// // unblock all signals which are registered with the
-// // scheduler
-// // call epoll
-// // block all relevant signals again
-// }
-//
-// // now handle the event
-//
-// The signal handler is then simply defined as
-//
-// static void Scheduler::sigHandler(int signal)
-// {
-// // make sure to restore the signal handler here if
-// // necessary
-// longjmp(Scheduler::instance().jmpBuffer_,signal);
-// }
-//
-// You should use sigaction to register the signal handlers and define
-// a sa_mask so all Scheduler-registered signals are automatically
-// *blocked* whenever one of the signals is called (including the
-// called signal!) (This also means, we will have to re-register all
-// signals if we change the registration of some signal since the
-// sa_mask changes). This ensures, that no two signals can be
-// delivered on top of each other. And of course any signal registered
-// with the scheduler must be blocked as soon as it is registered with
-// the scheduler.
-
#include "Scheduler.hh"
//#include "Scheduler.ih"
// Custom includes
-#include <errno.h>
-#include <sys/epoll.h>
-#include "Utils/Exception.hh"
-#include "Utils/MicroTime.hh"
-
-static const int EPollInitialSize = 16;
#define prefix_
///////////////////////////////cc.p////////////////////////////////////////
-prefix_ senf::Scheduler::Scheduler & senf::Scheduler::instance()
-{
- static Scheduler instance;
- return instance;
+namespace {
+ bool terminate_ (false);
+ bool running_ (false);
}
-prefix_ void senf::Scheduler::timeout(unsigned long timeout, TimerCallback const & cb)
+prefix_ void senf::scheduler::terminate()
{
- timerQueue_.push(TimerSpec(now()+1000*timeout,cb));
+ terminate_ = true;
}
-prefix_ senf::Scheduler::Scheduler()
- : epollFd_(epoll_create(EPollInitialSize))
+prefix_ void senf::scheduler::yield()
{
- if (epollFd_<0)
- throw SystemException(errno);
+ senf::scheduler::detail::FIFORunner::instance().yield();
}
-prefix_ void senf::Scheduler::do_add(int fd, SimpleCallback const & cb, int eventMask)
+prefix_ bool senf::scheduler::running()
{
- 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;
- }
+ return running_;
+}
- 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;
+prefix_ senf::ClockService::clock_type senf::scheduler::now()
+{
+ return running() ? eventTime() : ClockService::now();
+}
- epoll_event ev;
- memset(&ev,0,sizeof(ev));
- ev.events = i->second.epollMask();
- ev.data.fd = 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;
+ }
+
+ ~SchedulerScopedInit()
+ {
+ senf::scheduler::detail::TimerDispatcher::instance().disable();
+ senf::scheduler::detail::SignalDispatcher::instance().blockSignals();
+ senf::scheduler::detail::FIFORunner::instance().stopWatchdog();
+ running_ = false;
+ }
+ };
+}
- if (epoll_ctl(epollFd_, action, fd, &ev)<0)
- throw SystemException(errno);
+prefix_ void senf::scheduler::process()
+{
+ 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::do_remove(int fd, int eventMask)
+prefix_ void senf::scheduler::restart()
{
- FdTable::iterator i (fdTable_.find(fd));
- if (i == fdTable_.end())
- return;
+ 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();
+}
- 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;
+prefix_ bool senf::scheduler::empty()
+{
+ return detail::FdDispatcher::instance().empty()
+ && detail::TimerDispatcher::instance().empty()
+ && detail::FileDispatcher::instance().empty()
+ && detail::SignalDispatcher::instance().empty()
+ && detail::EventHookDispatcher::instance().empty();
+}
- epoll_event ev;
- memset(&ev,0,sizeof(ev));
- ev.events = i->second.epollMask();
- ev.data.fd = fd;
+prefix_ void senf::scheduler::hiresTimers()
+{
+#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()));
+}
- int action (EPOLL_CTL_MOD);
- if (ev.events==0) {
- action = EPOLL_CTL_DEL;
- fdTable_.erase(i);
- }
+///////////////////////////////////////////////////////////////////////////
+// senf::schedulerLogTimeSource
- if (epoll_ctl(epollFd_, action, fd, &ev)<0)
- throw SystemException(errno);
+prefix_ senf::log::time_type senf::scheduler::LogTimeSource::operator()()
+ const
+{
+ return eventTime();
}
+///////////////////////////////////////////////////////////////////////////
+// senf::scheduler::BlockSignals
-prefix_ int senf::Scheduler::EventSpec::epollMask()
- const
+prefix_ senf::scheduler::BlockSignals::BlockSignals(bool initiallyBlocked)
+ : blocked_ (false)
{
- int mask (0);
- if (cb_read) mask |= EPOLLIN;
- if (cb_prio) mask |= EPOLLPRI;
- if (cb_write) mask |= EPOLLOUT;
- return mask;
+ ::sigfillset(&allSigs_);
+ if (initiallyBlocked)
+ block();
}
-prefix_ void senf::Scheduler::process()
+prefix_ void senf::scheduler::BlockSignals::block()
{
- terminate_ = false;
- while (! terminate_) {
-
- MicroTime timeNow = now();
- while ( ! timerQueue_.empty() && timerQueue_.top().timeout <= timeNow ) {
- timerQueue_.top().cb();
- timerQueue_.pop();
- }
- if (terminate_)
- return;
- int timeout = timerQueue_.empty() ? -1 : int((timerQueue_.top().timeout - timeNow)/1000);
-
- struct epoll_event ev;
- int events = epoll_wait(epollFd_, &ev, 1, timeout);
- if (events<0)
- // Hmm ... man epoll says, it will NOT return with EINTR. I hope, this is true :-)
- throw SystemException(errno);
- if (events==0)
- // Timeout .. the handler will be run when going back to the loop top
- continue;
-
- FdTable::iterator i = fdTable_.find(ev.data.fd);
- BOOST_ASSERT (i != fdTable_.end() );
- // \todo Make this more efficient. Instead of copying the event-spec it should be
- // revalidated by monitoring add/remove calls
- EventSpec spec (i->second);
-
- unsigned extraFlags (0);
- if (ev.events & EPOLLHUP) extraFlags |= EV_HUP;
- if (ev.events & EPOLLERR) extraFlags |= EV_ERR;
-
- if (ev.events & EPOLLIN) {
- BOOST_ASSERT(spec.cb_read);
- spec.cb_read(EventId(EV_READ | extraFlags));
- }
- else if (ev.events & EPOLLPRI) {
- BOOST_ASSERT(spec.cb_prio);
- spec.cb_prio(EventId(EV_PRIO | extraFlags));
- }
- else if (ev.events & 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));
- }
- }
+ if (blocked_)
+ return;
+ ::sigprocmask(SIG_BLOCK, &allSigs_, &savedSigs_);
+ blocked_ = true;
+}
+
+prefix_ void senf::scheduler::BlockSignals::unblock()
+{
+ if (!blocked_)
+ return;
+ ::sigprocmask(SIG_SETMASK, &savedSigs_, 0);
+ blocked_ = false;
}
///////////////////////////////cc.e////////////////////////////////////////
// indent-tabs-mode: nil
// ispell-local-dictionary: "american"
// compile-command: "scons -u test"
+// comment-column: 40
// End:
projects / senf.git / blobdiff