Merge pull request #48331 from tchaikov/crimson-stop

crimson/osd: shutdown on osdmaps' demand

Reviewed-by: Samuel Just <sjust@redhat.com>

src/crimson/osd/main.cc

@@ -8,7 +8,6 @@
 #include <fstream>
 #include <random>
 
-#include <seastar/apps/lib/stop_signal.hh>
 #include <seastar/core/app-template.hh>
 #include <seastar/core/print.hh>
 #include <seastar/core/prometheus.hh>
@@ -27,6 +26,7 @@
 #include "crimson/common/fatal_signal.h"
 #include "crimson/mon/MonClient.h"
 #include "crimson/net/Messenger.h"
+#include "crimson/osd/stop_signal.h"
 #include "global/pidfile.h"
 #include "osd.h"
 
@@ -295,7 +295,8 @@ int main(int argc, const char* argv[])
             local_conf().get_config_values()).get();
 
           crimson::osd::OSD osd(
-	    whoami, nonce, std::ref(*store), cluster_msgr, client_msgr,
+            whoami, nonce, std::ref(should_stop.abort_source()),
+            std::ref(*store), cluster_msgr, client_msgr,
 	    hb_front_msgr, hb_back_msgr);
 
           if (config.count("mkkey")) {

src/crimson/osd/osd.cc

@@ -75,6 +75,7 @@ using crimson::os::FuturizedStore;
 namespace crimson::osd {
 
 OSD::OSD(int id, uint32_t nonce,
+	 seastar::abort_source& abort_source,
          crimson::os::FuturizedStore& store,
          crimson::net::MessengerRef cluster_msgr,
          crimson::net::MessengerRef public_msgr,
@@ -82,6 +83,7 @@ OSD::OSD(int id, uint32_t nonce,
          crimson::net::MessengerRef hb_back_msgr)
   : whoami{id},
     nonce{nonce},
+    abort_source{abort_source},
     // do this in background
     beacon_timer{[this] { (void)send_beacon(); }},
     cluster_msgr{cluster_msgr},
@@ -1166,9 +1168,8 @@ seastar::future<> OSD::restart()
 
 seastar::future<> OSD::shutdown()
 {
-  // TODO
-  superblock.mounted = boot_epoch;
-  superblock.clean_thru = osdmap->get_epoch();
+  logger().info("shutting down per osdmap");
+  abort_source.request_abort();
   return seastar::now();
 }
 

src/crimson/osd/osd.h

@@ -3,6 +3,7 @@
 
 #pragma once
 
+#include <seastar/core/abort_source.hh>
 #include <seastar/core/future.hh>
 #include <seastar/core/shared_future.hh>
 #include <seastar/core/gate.hh>
@@ -62,6 +63,7 @@ class OSD final : public crimson::net::Dispatcher,
 		  private crimson::mgr::WithStats {
   const int whoami;
   const uint32_t nonce;
+  seastar::abort_source& abort_source;
   seastar::timer<seastar::lowres_clock> beacon_timer;
   // talk with osd
   crimson::net::MessengerRef cluster_msgr;
@@ -116,6 +118,7 @@ class OSD final : public crimson::net::Dispatcher,
 
 public:
   OSD(int id, uint32_t nonce,
+      seastar::abort_source& abort_source,
       crimson::os::FuturizedStore& store,
       crimson::net::MessengerRef cluster_msgr,
       crimson::net::MessengerRef client_msgr,

src/crimson/osd/stop_signal.h

@@ -0,0 +1,83 @@
+/*
+ * This file is open source software, licensed to you under the terms
+ * of the Apache License, Version 2.0 (the "License").  See the NOTICE file
+ * distributed with this work for additional information regarding copyright
+ * ownership.  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.
+ */
+
+/*
+ * Copyright (C) 2020 Cloudius Systems, Ltd.
+ */
+
+#pragma once
+
+#include <seastar/core/abort_source.hh>
+#include <seastar/core/reactor.hh>
+#include <seastar/core/condition-variable.hh>
+
+/// Seastar apps lib namespace
+
+namespace seastar_apps_lib {
+
+
+/// \brief Futurized SIGINT/SIGTERM signals handler class
+///
+/// Seastar-style helper class that allows easy waiting for SIGINT/SIGTERM signals
+/// from your app.
+///
+/// Example:
+/// \code
+/// #include <seastar/apps/lib/stop_signal.hh>
+/// ...
+/// int main() {
+/// ...
+/// seastar::thread th([] {
+///    seastar_apps_lib::stop_signal stop_signal;
+///    <some code>
+///    stop_signal.wait().get();  // this will wait till we receive SIGINT or SIGTERM signal
+/// });
+/// \endcode
+class stop_signal {
+    seastar::condition_variable _cond;
+    seastar::abort_source _abort_source;
+
+private:
+    void on_signal() {
+        if (stopping()) {
+            return;
+        }
+        _abort_source.request_abort();
+        _cond.broadcast();
+    }
+public:
+    stop_signal() {
+        seastar::engine().handle_signal(SIGINT, [this] { on_signal(); });
+        seastar::engine().handle_signal(SIGTERM, [this] { on_signal(); });
+    }
+    ~stop_signal() {
+        // There's no way to unregister a handler yet, so register a no-op handler instead.
+        seastar::engine().handle_signal(SIGINT, [] {});
+        seastar::engine().handle_signal(SIGTERM, [] {});
+    }
+    seastar::future<> wait() {
+        return _cond.wait([this] { return _abort_source.abort_requested(); });
+    }
+    bool stopping() const {
+        return _abort_source.abort_requested();
+    }
+    auto& abort_source() {
+        return _abort_source;
+    }
+};
+}