bmc: add preparation step before data is received
Add a preparation systemd trigger event before data is received. On
systems under memory pressure, this'll trigger a service that can do
things like flush caches.
Signed-off-by: Patrick Venture <venture@google.com>
Change-Id: I175177f4a91b58d9f163098572a9d2614002b718
diff --git a/prepare_systemd.cpp b/prepare_systemd.cpp
new file mode 100644
index 0000000..b16bc99
--- /dev/null
+++ b/prepare_systemd.cpp
@@ -0,0 +1,71 @@
+/*
+ * Copyright 2019 Google Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "prepare_systemd.hpp"
+
+#include "status.hpp"
+
+#include <memory>
+
+namespace ipmi_flash
+{
+
+std::unique_ptr<TriggerableActionInterface>
+ SystemdPreparation::CreatePreparation(sdbusplus::bus::bus&& bus,
+ const std::string& service)
+{
+ return std::make_unique<SystemdPreparation>(std::move(bus), service);
+}
+
+bool SystemdPreparation::trigger()
+{
+ static constexpr auto systemdService = "org.freedesktop.systemd1";
+ static constexpr auto systemdRoot = "/org/freedesktop/systemd1";
+ static constexpr auto systemdInterface = "org.freedesktop.systemd1.Manager";
+
+ auto method = bus.new_method_call(systemdService, systemdRoot,
+ systemdInterface, "StartUnit");
+ method.append(triggerService);
+ method.append("replace");
+
+ try
+ {
+ bus.call_noreply(method);
+ }
+ catch (const sdbusplus::exception::SdBusError& ex)
+ {
+ /* TODO: Once logging supports unit-tests, add a log message to test
+ * this failure.
+ */
+ state = ActionStatus::failed;
+ return false;
+ }
+
+ state = ActionStatus::success;
+ return true;
+}
+
+void SystemdPreparation::abort()
+{
+ return;
+}
+
+ActionStatus SystemdPreparation::status()
+{
+ return state;
+}
+
+} // namespace ipmi_flash