Adding upstream version 18.2.2.upstream/18.2.2

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 225 insertions, 0 deletions

diff --git a/src/common/Timer.cc b/src/common/Timer.cc
new file mode 100644
index 000000000..48c79d613
--- /dev/null
+++ b/src/common/Timer.cc
@@ -0,0 +1,225 @@
+// -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*-
+// vim: ts=8 sw=2 smarttab
+/*
+ * Ceph - scalable distributed file system
+ *
+ * Copyright (C) 2004-2006 Sage Weil <sage@newdream.net>
+ *
+ * This is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License version 2.1, as published by the Free Software
+ * Foundation.  See file COPYING.
+ *
+ */
+
+#include "Cond.h"
+#include "Timer.h"
+
+
+#define dout_subsys ceph_subsys_timer
+#undef dout_prefix
+#define dout_prefix *_dout << "timer(" << this << ")."
+
+using std::pair;
+
+using ceph::operator <<;
+
+template <class Mutex>
+class CommonSafeTimerThread : public Thread {
+  CommonSafeTimer<Mutex> *parent;
+public:
+  explicit CommonSafeTimerThread(CommonSafeTimer<Mutex> *s) : parent(s) {}
+  void *entry() override {
+    parent->timer_thread();
+    return NULL;
+  }
+};
+
+template <class Mutex>
+CommonSafeTimer<Mutex>::CommonSafeTimer(CephContext *cct_, Mutex &l, bool safe_callbacks)
+  : cct(cct_), lock(l),
+    safe_callbacks(safe_callbacks),
+    thread(NULL),
+    stopping(false)
+{
+}
+
+template <class Mutex>
+CommonSafeTimer<Mutex>::~CommonSafeTimer()
+{
+  ceph_assert(thread == NULL);
+}
+
+template <class Mutex>
+void CommonSafeTimer<Mutex>::init()
+{
+  ldout(cct,10) << "init" << dendl;
+  thread = new CommonSafeTimerThread<Mutex>(this);
+  thread->create("safe_timer");
+}
+
+template <class Mutex>
+void CommonSafeTimer<Mutex>::shutdown()
+{
+  ldout(cct,10) << "shutdown" << dendl;
+  if (thread) {
+    ceph_assert(ceph_mutex_is_locked(lock));
+    cancel_all_events();
+    stopping = true;
+    cond.notify_all();
+    lock.unlock();
+    thread->join();
+    lock.lock();
+    delete thread;
+    thread = NULL;
+  }
+}
+
+template <class Mutex>
+void CommonSafeTimer<Mutex>::timer_thread()
+{
+  std::unique_lock l{lock};
+  ldout(cct,10) << "timer_thread starting" << dendl;
+  while (!stopping) {
+    auto now = clock_t::now();
+
+    while (!schedule.empty()) {
+      auto p = schedule.begin();
+
+      // is the future now?
+      if (p->first > now)
+	break;
+
+      Context *callback = p->second;
+      events.erase(callback);
+      schedule.erase(p);
+      ldout(cct,10) << "timer_thread executing " << callback << dendl;
+      
+      if (!safe_callbacks) {
+	l.unlock();
+	callback->complete(0);
+	l.lock();
+      } else {
+	callback->complete(0);
+      }
+    }
+
+    // recheck stopping if we dropped the lock
+    if (!safe_callbacks && stopping)
+      break;
+
+    ldout(cct,20) << "timer_thread going to sleep" << dendl;
+    if (schedule.empty()) {
+      cond.wait(l);
+    } else {
+      auto when = schedule.begin()->first;
+      cond.wait_until(l, when);
+    }
+    ldout(cct,20) << "timer_thread awake" << dendl;
+  }
+  ldout(cct,10) << "timer_thread exiting" << dendl;
+}
+
+template <class Mutex>
+Context* CommonSafeTimer<Mutex>::add_event_after(double seconds, Context *callback)
+{
+  return add_event_after(ceph::make_timespan(seconds), callback);
+}
+
+template <class Mutex>
+Context* CommonSafeTimer<Mutex>::add_event_after(ceph::timespan duration, Context *callback)
+{
+  ceph_assert(ceph_mutex_is_locked(lock));
+
+  auto when = clock_t::now() + duration;
+  return add_event_at(when, callback);
+}
+
+template <class Mutex>
+Context* CommonSafeTimer<Mutex>::add_event_at(CommonSafeTimer<Mutex>::clock_t::time_point when, Context *callback)
+{
+  ceph_assert(ceph_mutex_is_locked(lock));
+  ldout(cct,10) << __func__ << " " << when << " -> " << callback << dendl;
+  if (stopping) {
+    ldout(cct,5) << __func__ << " already shutdown, event not added" << dendl;
+    delete callback;
+    return nullptr;
+  }
+  scheduled_map_t::value_type s_val(when, callback);
+  scheduled_map_t::iterator i = schedule.insert(s_val);
+
+  event_lookup_map_t::value_type e_val(callback, i);
+  pair < event_lookup_map_t::iterator, bool > rval(events.insert(e_val));
+
+  /* If you hit this, you tried to insert the same Context* twice. */
+  ceph_assert(rval.second);
+
+  /* If the event we have just inserted comes before everything else, we need to
+   * adjust our timeout. */
+  if (i == schedule.begin())
+    cond.notify_all();
+  return callback;
+}
+
+template <class Mutex>
+Context* CommonSafeTimer<Mutex>::add_event_at(ceph::real_clock::time_point when, Context *callback)
+{
+  ceph_assert(ceph_mutex_is_locked(lock));
+  // convert from real_clock to mono_clock
+  auto mono_now = ceph::mono_clock::now();
+  auto real_now = ceph::real_clock::now();
+  const auto delta = when - real_now;
+  const auto mono_atime = (mono_now +
+			   std::chrono::ceil<clock_t::duration>(delta));
+  return add_event_at(mono_atime, callback);
+}
+
+template <class Mutex>
+bool CommonSafeTimer<Mutex>::cancel_event(Context *callback)
+{
+  ceph_assert(ceph_mutex_is_locked(lock));
+  
+  auto p = events.find(callback);
+  if (p == events.end()) {
+    ldout(cct,10) << "cancel_event " << callback << " not found" << dendl;
+    return false;
+  }
+
+  ldout(cct,10) << "cancel_event " << p->second->first << " -> " << callback << dendl;
+  delete p->first;
+
+  schedule.erase(p->second);
+  events.erase(p);
+  return true;
+}
+
+template <class Mutex>
+void CommonSafeTimer<Mutex>::cancel_all_events()
+{
+  ldout(cct,10) << "cancel_all_events" << dendl;
+  ceph_assert(ceph_mutex_is_locked(lock));
+
+  while (!events.empty()) {
+    auto p = events.begin();
+    ldout(cct,10) << " cancelled " << p->second->first << " -> " << p->first << dendl;
+    delete p->first;
+    schedule.erase(p->second);
+    events.erase(p);
+  }
+}
+
+template <class Mutex>
+void CommonSafeTimer<Mutex>::dump(const char *caller) const
+{
+  if (!caller)
+    caller = "";
+  ldout(cct,10) << "dump " << caller << dendl;
+
+  for (scheduled_map_t::const_iterator s = schedule.begin();
+       s != schedule.end();
+       ++s)
+    ldout(cct,10) << " " << s->first << "->" << s->second << dendl;
+}
+
+template class CommonSafeTimer<ceph::mutex>;
+template class CommonSafeTimer<ceph::fair_mutex>;