1 files changed, 176 insertions, 0 deletions
diff --git a/src/rgw/rgw_realm_reloader.cc b/src/rgw/rgw_realm_reloader.cc
new file mode 100644
index 00000000..1fd48db0
--- /dev/null
+++ b/src/rgw/rgw_realm_reloader.cc
@@ -0,0 +1,176 @@
+// -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*-
+// vim: ts=8 sw=2 smarttab
+
+#include "rgw_realm_reloader.h"
+#include "rgw_rados.h"
+
+#include "rgw_bucket.h"
+#include "rgw_log.h"
+#include "rgw_rest.h"
+#include "rgw_user.h"
+
+#include "services/svc_zone.h"
+
+#include "common/errno.h"
+
+#define dout_subsys ceph_subsys_rgw
+
+#undef dout_prefix
+#define dout_prefix (*_dout << "rgw realm reloader: ")
+
+
+// safe callbacks from SafeTimer are unneccessary. reload() can take a long
+// time, so we don't want to hold the mutex and block handle_notify() for the
+// duration
+static constexpr bool USE_SAFE_TIMER_CALLBACKS = false;
+
+
+RGWRealmReloader::RGWRealmReloader(RGWRados*& store, std::map<std::string, std::string>& service_map_meta,
+                                   Pauser* frontends)
+  : store(store),
+    service_map_meta(service_map_meta),
+    frontends(frontends),
+    timer(store->ctx(), mutex, USE_SAFE_TIMER_CALLBACKS),
+    mutex("RGWRealmReloader"),
+    reload_scheduled(nullptr)
+{
+  timer.init();
+}
+
+RGWRealmReloader::~RGWRealmReloader()
+{
+  Mutex::Locker lock(mutex);
+  timer.shutdown();
+}
+
+class RGWRealmReloader::C_Reload : public Context {
+  RGWRealmReloader* reloader;
+ public:
+  explicit C_Reload(RGWRealmReloader* reloader) : reloader(reloader) {}
+  void finish(int r) override { reloader->reload(); }
+};
+
+void RGWRealmReloader::handle_notify(RGWRealmNotify type,
+                                     bufferlist::const_iterator& p)
+{
+  if (!store) {
+    /* we're in the middle of reload */
+    return;
+  }
+
+  CephContext *const cct = store->ctx();
+
+  Mutex::Locker lock(mutex);
+  if (reload_scheduled) {
+    ldout(cct, 4) << "Notification on realm, reconfiguration "
+        "already scheduled" << dendl;
+    return;
+  }
+
+  reload_scheduled = new C_Reload(this);
+  cond.SignalOne(); // wake reload() if it blocked on a bad configuration
+
+  // schedule reload() without delay
+  timer.add_event_after(0, reload_scheduled);
+
+  ldout(cct, 4) << "Notification on realm, reconfiguration scheduled" << dendl;
+}
+
+void RGWRealmReloader::reload()
+{
+  CephContext *const cct = store->ctx();
+  ldout(cct, 1) << "Pausing frontends for realm update..." << dendl;
+
+  frontends->pause();
+
+  ldout(cct, 1) << "Frontends paused" << dendl;
+
+  // TODO: make RGWRados responsible for rgw_log_usage lifetime
+  rgw_log_usage_finalize();
+
+  // destroy the existing store
+  RGWStoreManager::close_storage(store);
+  store = nullptr;
+
+  ldout(cct, 1) << "Store closed" << dendl;
+  {
+    // allow a new notify to reschedule us. it's important that we do this
+    // before we start loading the new realm, or we could miss some updates
+    Mutex::Locker lock(mutex);
+    reload_scheduled = nullptr;
+  }
+
+  while (!store) {
+    // recreate and initialize a new store
+    store =
+      RGWStoreManager::get_storage(cct,
+				   cct->_conf->rgw_enable_gc_threads,
+				   cct->_conf->rgw_enable_lc_threads,
+				   cct->_conf->rgw_enable_quota_threads,
+				   cct->_conf->rgw_run_sync_thread,
+				   cct->_conf.get_val<bool>("rgw_dynamic_resharding"),
+				   cct->_conf->rgw_cache_enabled);
+
+    ldout(cct, 1) << "Creating new store" << dendl;
+
+    RGWRados* store_cleanup = nullptr;
+    {
+      Mutex::Locker lock(mutex);
+
+      // failure to recreate RGWRados is not a recoverable error, but we
+      // don't want to assert or abort the entire cluster.  instead, just
+      // sleep until we get another notification, and retry until we get
+      // a working configuration
+      if (store == nullptr) {
+        lderr(cct) << "Failed to reinitialize RGWRados after a realm "
+            "configuration update. Waiting for a new update." << dendl;
+
+        // sleep until another event is scheduled
+        while (!reload_scheduled)
+          cond.Wait(mutex);
+
+        ldout(cct, 1) << "Woke up with a new configuration, retrying "
+            "RGWRados initialization." << dendl;
+      }
+
+      if (reload_scheduled) {
+        // cancel the event; we'll handle it now
+        timer.cancel_event(reload_scheduled);
+        reload_scheduled = nullptr;
+
+        // if we successfully created a store, clean it up outside of the lock,
+        // then continue to loop and recreate another
+        std::swap(store, store_cleanup);
+      }
+    }
+
+    if (store_cleanup) {
+      ldout(cct, 4) << "Got another notification, restarting RGWRados "
+          "initialization." << dendl;
+
+      RGWStoreManager::close_storage(store_cleanup);
+    }
+  }
+
+  int r = store->register_to_service_map("rgw", service_map_meta);
+  if (r < 0) {
+    lderr(cct) << "ERROR: failed to register to service map: " << cpp_strerror(-r) << dendl;
+
+    /* ignore error */
+  }
+
+  ldout(cct, 1) << "Finishing initialization of new store" << dendl;
+  // finish initializing the new store
+  ldout(cct, 1) << " - REST subsystem init" << dendl;
+  rgw_rest_init(cct, store, store->svc.zone->get_zonegroup());
+  ldout(cct, 1) << " - user subsystem init" << dendl;
+  rgw_user_init(store);
+  ldout(cct, 1) << " - user subsystem init" << dendl;
+  rgw_bucket_init(store->meta_mgr);
+  ldout(cct, 1) << " - usage subsystem init" << dendl;
+  rgw_log_usage_init(cct, store);
+
+  ldout(cct, 1) << "Resuming frontends with new realm configuration." << dendl;
+
+  frontends->resume(store);
+}