1 files changed, 109 insertions, 0 deletions
diff --git a/src/librbd/cache/pwl/SyncPoint.cc b/src/librbd/cache/pwl/SyncPoint.cc
new file mode 100644
index 000000000..8fb2f8205
--- /dev/null
+++ b/src/librbd/cache/pwl/SyncPoint.cc
@@ -0,0 +1,109 @@
+// -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*-
+// vim: ts=8 sw=2 smarttab
+
+#include "SyncPoint.h"
+
+#define dout_subsys ceph_subsys_rbd_pwl
+#undef dout_prefix
+#define dout_prefix *_dout << "librbd::cache::pwl::SyncPoint: " << this << " " \
+                           <<  __func__ << ": "
+
+namespace librbd {
+namespace cache {
+namespace pwl {
+
+SyncPoint::SyncPoint(uint64_t sync_gen_num, CephContext *cct)
+  : log_entry(std::make_shared<SyncPointLogEntry>(sync_gen_num)), m_cct(cct) {
+  m_prior_log_entries_persisted = new C_Gather(cct, nullptr);
+  m_sync_point_persist = new C_Gather(cct, nullptr);
+  on_sync_point_appending.reserve(MAX_WRITES_PER_SYNC_POINT + 2);
+  on_sync_point_persisted.reserve(MAX_WRITES_PER_SYNC_POINT + 2);
+  ldout(m_cct, 20) << "sync point " << sync_gen_num << dendl;
+}
+
+SyncPoint::~SyncPoint() {
+  ceph_assert(on_sync_point_appending.empty());
+  ceph_assert(on_sync_point_persisted.empty());
+  ceph_assert(!earlier_sync_point);
+}
+
+std::ostream &operator<<(std::ostream &os,
+                         const SyncPoint &p) {
+  os << "log_entry=[" << *p.log_entry << "], "
+     << "earlier_sync_point=" << p.earlier_sync_point << ", "
+     << "later_sync_point=" << p.later_sync_point << ", "
+     << "m_final_op_sequence_num=" << p.m_final_op_sequence_num << ", "
+     << "m_prior_log_entries_persisted=" << p.m_prior_log_entries_persisted << ", "
+     << "m_prior_log_entries_persisted_complete=" << p.m_prior_log_entries_persisted_complete << ", "
+     << "m_append_scheduled=" << p.m_append_scheduled << ", "
+     << "appending=" << p.appending << ", "
+     << "on_sync_point_appending=" << p.on_sync_point_appending.size() << ", "
+     << "on_sync_point_persisted=" << p.on_sync_point_persisted.size() << "";
+  return os;
+}
+
+void SyncPoint::persist_gather_set_finisher(Context *ctx) {
+  m_append_scheduled = true;
+  /* All prior sync points that are still in this list must already be scheduled for append */
+  std::shared_ptr<SyncPoint> previous = earlier_sync_point;
+  while (previous) {
+    ceph_assert(previous->m_append_scheduled);
+    previous = previous->earlier_sync_point;
+  }
+
+  m_sync_point_persist->set_finisher(ctx);
+}
+
+void SyncPoint::persist_gather_activate() {
+  m_sync_point_persist->activate();
+}
+
+Context* SyncPoint::persist_gather_new_sub() {
+  return m_sync_point_persist->new_sub();
+}
+
+void SyncPoint::prior_persisted_gather_activate() {
+  m_prior_log_entries_persisted->activate();
+}
+
+Context* SyncPoint::prior_persisted_gather_new_sub() {
+  return m_prior_log_entries_persisted->new_sub();
+}
+
+void SyncPoint::prior_persisted_gather_set_finisher() {
+  Context *sync_point_persist_ready = persist_gather_new_sub();
+  std::shared_ptr<SyncPoint> sp = shared_from_this();
+  m_prior_log_entries_persisted->
+    set_finisher(new LambdaContext([this, sp, sync_point_persist_ready](int r) {
+      ldout(m_cct, 20) << "Prior log entries persisted for sync point =["
+                       << sp << "]" << dendl;
+      sp->m_prior_log_entries_persisted_result = r;
+      sp->m_prior_log_entries_persisted_complete = true;
+      sync_point_persist_ready->complete(r);
+    }));
+}
+
+void SyncPoint::add_in_on_persisted_ctxs(Context* ctx) {
+  on_sync_point_persisted.push_back(ctx);
+}
+
+void SyncPoint::add_in_on_appending_ctxs(Context* ctx) {
+  on_sync_point_appending.push_back(ctx);
+}
+
+void SyncPoint::setup_earlier_sync_point(std::shared_ptr<SyncPoint> sync_point,
+                                         uint64_t last_op_sequence_num) {
+    earlier_sync_point = sync_point;
+    log_entry->prior_sync_point_flushed = false;
+    earlier_sync_point->log_entry->next_sync_point_entry = log_entry;
+    earlier_sync_point->later_sync_point = shared_from_this();
+    earlier_sync_point->m_final_op_sequence_num = last_op_sequence_num;
+    if (!earlier_sync_point->appending) {
+      /* Append of new sync point deferred until old sync point is appending */
+      earlier_sync_point->add_in_on_appending_ctxs(prior_persisted_gather_new_sub());
+    }
+}
+
+} // namespace pwl
+} // namespace cache
+} // namespace librbd