1 files changed, 98 insertions, 0 deletions
diff --git a/src/librbd/watcher/Notifier.cc b/src/librbd/watcher/Notifier.cc
new file mode 100644
index 00000000..dfb95aec
--- /dev/null
+++ b/src/librbd/watcher/Notifier.cc
@@ -0,0 +1,98 @@
+// -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*-
+// vim: ts=8 sw=2 smarttab
+
+#include "librbd/watcher/Notifier.h"
+#include "common/WorkQueue.h"
+#include "librbd/ImageCtx.h"
+#include "librbd/Utils.h"
+#include "librbd/watcher/Types.h"
+
+#define dout_subsys ceph_subsys_rbd
+#undef dout_prefix
+#define dout_prefix *_dout << "librbd::watcher::Notifier: " \
+                           << this << " " << __func__ << ": "
+
+namespace librbd {
+namespace watcher {
+
+const uint64_t Notifier::NOTIFY_TIMEOUT = 5000;
+
+Notifier::C_AioNotify::C_AioNotify(Notifier *notifier, NotifyResponse *response,
+                                   Context *on_finish)
+  : notifier(notifier), response(response), on_finish(on_finish) {
+}
+
+void Notifier::C_AioNotify::finish(int r) {
+  if (response != nullptr) {
+    if (r == 0 || r == -ETIMEDOUT) {
+      try {
+        auto it = out_bl.cbegin();
+        decode(*response, it);
+      } catch (const buffer::error &err) {
+        r = -EBADMSG;
+      }
+    }
+  }
+  notifier->handle_notify(r, on_finish);
+}
+
+Notifier::Notifier(ContextWQ *work_queue, IoCtx &ioctx, const std::string &oid)
+  : m_work_queue(work_queue), m_ioctx(ioctx), m_oid(oid),
+    m_aio_notify_lock(util::unique_lock_name(
+      "librbd::object_watcher::Notifier::m_aio_notify_lock", this)) {
+  m_cct = reinterpret_cast<CephContext *>(m_ioctx.cct());
+}
+
+Notifier::~Notifier() {
+  Mutex::Locker aio_notify_locker(m_aio_notify_lock);
+  ceph_assert(m_pending_aio_notifies == 0);
+}
+
+void Notifier::flush(Context *on_finish) {
+  Mutex::Locker aio_notify_locker(m_aio_notify_lock);
+  if (m_pending_aio_notifies == 0) {
+    m_work_queue->queue(on_finish, 0);
+    return;
+  }
+
+  m_aio_notify_flush_ctxs.push_back(on_finish);
+}
+
+void Notifier::notify(bufferlist &bl, NotifyResponse *response,
+                      Context *on_finish) {
+  {
+    Mutex::Locker aio_notify_locker(m_aio_notify_lock);
+    ++m_pending_aio_notifies;
+
+    ldout(m_cct, 20) << "pending=" << m_pending_aio_notifies << dendl;
+  }
+
+  C_AioNotify *ctx = new C_AioNotify(this, response, on_finish);
+  librados::AioCompletion *comp = util::create_rados_callback(ctx);
+  int r = m_ioctx.aio_notify(m_oid, comp, bl, NOTIFY_TIMEOUT, &ctx->out_bl);
+  ceph_assert(r == 0);
+  comp->release();
+}
+
+void Notifier::handle_notify(int r, Context *on_finish) {
+  ldout(m_cct, 20) << "r=" << r << dendl;
+
+  Mutex::Locker aio_notify_locker(m_aio_notify_lock);
+  ceph_assert(m_pending_aio_notifies > 0);
+  --m_pending_aio_notifies;
+
+  ldout(m_cct, 20) << "pending=" << m_pending_aio_notifies << dendl;
+  if (m_pending_aio_notifies == 0) {
+    for (auto ctx : m_aio_notify_flush_ctxs) {
+      m_work_queue->queue(ctx, 0);
+    }
+    m_aio_notify_flush_ctxs.clear();
+  }
+
+  if (on_finish != nullptr) {
+    m_work_queue->queue(on_finish, r);
+  }
+}
+
+} // namespace watcher
+} // namespace librbd