Adding upstream version 16.2.11+ds.upstream/16.2.11+dsupstream

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

1 files changed, 167 insertions, 0 deletions

diff --git a/src/journal/FutureImpl.cc b/src/journal/FutureImpl.cc
new file mode 100644
index 000000000..4e804f8dc
--- /dev/null
+++ b/src/journal/FutureImpl.cc
@@ -0,0 +1,167 @@
+// -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*-
+// vim: ts=8 sw=2 smarttab
+
+#include "journal/FutureImpl.h"
+#include "journal/Utils.h"
+
+namespace journal {
+
+FutureImpl::FutureImpl(uint64_t tag_tid, uint64_t entry_tid,
+                       uint64_t commit_tid)
+  : m_tag_tid(tag_tid),
+    m_entry_tid(entry_tid),
+    m_commit_tid(commit_tid),
+    m_consistent_ack(this)
+{
+}
+
+void FutureImpl::init(const ceph::ref_t<FutureImpl> &prev_future) {
+  // chain ourself to the prior future (if any) to that we known when the
+  // journal is consistent
+  if (prev_future) {
+    m_prev_future = prev_future;
+    m_prev_future->wait(&m_consistent_ack);
+  } else {
+    m_consistent_ack.complete(0);
+  }
+}
+
+void FutureImpl::flush(Context *on_safe) {
+
+  bool complete;
+  FlushHandlers flush_handlers;
+  ceph::ref_t<FutureImpl> prev_future;
+  {
+    std::lock_guard locker{m_lock};
+    complete = (m_safe && m_consistent);
+    if (!complete) {
+      if (on_safe != nullptr) {
+        m_contexts.push_back(on_safe);
+      }
+
+      prev_future = prepare_flush(&flush_handlers, m_lock);
+    }
+  }
+
+  // instruct prior futures to flush as well
+  while (prev_future) {
+    prev_future = prev_future->prepare_flush(&flush_handlers);
+  }
+
+  if (complete && on_safe != NULL) {
+    on_safe->complete(m_return_value);
+  } else if (!flush_handlers.empty()) {
+    // attached to journal object -- instruct it to flush all entries through
+    // this one.  possible to become detached while lock is released, so flush
+    // will be re-requested by the object if it doesn't own the future
+    for (auto &pair : flush_handlers) {
+      pair.first->flush(pair.second);
+    }
+  }
+}
+
+ceph::ref_t<FutureImpl> FutureImpl::prepare_flush(FlushHandlers *flush_handlers) {
+  std::lock_guard locker{m_lock};
+  return prepare_flush(flush_handlers, m_lock);
+}
+
+ceph::ref_t<FutureImpl> FutureImpl::prepare_flush(FlushHandlers *flush_handlers,
+                                        ceph::mutex &lock) {
+  ceph_assert(ceph_mutex_is_locked(m_lock));
+
+  if (m_flush_state == FLUSH_STATE_NONE) {
+    m_flush_state = FLUSH_STATE_REQUESTED;
+
+    auto h = m_flush_handler;
+    if (h) {
+      flush_handlers->try_emplace(std::move(h), this);
+    }
+  }
+  return m_prev_future;
+}
+
+void FutureImpl::wait(Context *on_safe) {
+  ceph_assert(on_safe != NULL);
+  {
+    std::lock_guard locker{m_lock};
+    if (!m_safe || !m_consistent) {
+      m_contexts.push_back(on_safe);
+      return;
+    }
+  }
+
+  on_safe->complete(m_return_value);
+}
+
+bool FutureImpl::is_complete() const {
+  std::lock_guard locker{m_lock};
+  return m_safe && m_consistent;
+}
+
+int FutureImpl::get_return_value() const {
+  std::lock_guard locker{m_lock};
+  ceph_assert(m_safe && m_consistent);
+  return m_return_value;
+}
+
+bool FutureImpl::attach(FlushHandler::ref flush_handler) {
+  std::lock_guard locker{m_lock};
+  ceph_assert(!m_flush_handler);
+  m_flush_handler = std::move(flush_handler);
+  return m_flush_state != FLUSH_STATE_NONE;
+}
+
+void FutureImpl::safe(int r) {
+  m_lock.lock();
+  ceph_assert(!m_safe);
+  m_safe = true;
+  if (m_return_value == 0) {
+    m_return_value = r;
+  }
+
+  m_flush_handler.reset();
+  if (m_consistent) {
+    finish_unlock();
+  } else {
+    m_lock.unlock();
+  }
+}
+
+void FutureImpl::consistent(int r) {
+  m_lock.lock();
+  ceph_assert(!m_consistent);
+  m_consistent = true;
+  m_prev_future.reset();
+  if (m_return_value == 0) {
+    m_return_value = r;
+  }
+
+  if (m_safe) {
+    finish_unlock();
+  } else {
+    m_lock.unlock();
+  }
+}
+
+void FutureImpl::finish_unlock() {
+  ceph_assert(ceph_mutex_is_locked(m_lock));
+  ceph_assert(m_safe && m_consistent);
+
+  Contexts contexts;
+  contexts.swap(m_contexts);
+
+  m_lock.unlock();
+  for (Contexts::iterator it = contexts.begin();
+       it != contexts.end(); ++it) {
+    (*it)->complete(m_return_value);
+  }
+}
+
+std::ostream &operator<<(std::ostream &os, const FutureImpl &future) {
+  os << "Future[tag_tid=" << future.m_tag_tid << ", "
+     << "entry_tid=" << future.m_entry_tid << ", "
+     << "commit_tid=" << future.m_commit_tid << "]";
+  return os;
+}
+
+} // namespace journal