1 files changed, 26 insertions, 19 deletions

diff --git a/documentapi/src/vespa/documentapi/messagebus/policies/contentpolicy.h b/documentapi/src/vespa/documentapi/messagebus/policies/contentpolicy.h
index e49ad378b90..7a3675c3001 100644
--- a/documentapi/src/vespa/documentapi/messagebus/policies/contentpolicy.h
+++ b/documentapi/src/vespa/documentapi/messagebus/policies/contentpolicy.h
@@ -6,55 +6,62 @@
 #include <vespa/vdslib/distribution/distribution.h>
 #include <vespa/document/bucket/bucketidfactory.h>
 #include <vespa/messagebus/routing/hop.h>
+#include <shared_mutex>
 
 namespace config {
     class ICallback;
     class ConfigFetcher;
 }
 
-namespace storage {
-namespace lib {
+namespace storage::lib {
     class Distribution;
     class ClusterState;
 }
-}
 
 namespace documentapi {
 
 class ContentPolicy : public ExternSlobrokPolicy
 {
 private:
-    document::BucketIdFactory _bucketIdFactory;
-    std::unique_ptr<storage::lib::ClusterState> _state;
-    string _clusterName;
-    string _clusterConfigId;
-    std::unique_ptr<config::ICallback>          _callBack;
-    std::unique_ptr<config::ConfigFetcher>      _configFetcher;
-    std::unique_ptr<storage::lib::Distribution> _distribution;
-    std::unique_ptr<storage::lib::Distribution> _nextDistribution;
+    document::BucketIdFactory                         _bucketIdFactory;
+    mutable std::shared_mutex                         _rw_lock;
+    std::shared_ptr<const storage::lib::ClusterState> _state;
+    string                                            _clusterName;
+    string                                            _clusterConfigId;
+    std::unique_ptr<config::ICallback>                _callBack;
+    std::unique_ptr<config::ConfigFetcher>            _configFetcher;
+    std::shared_ptr<const storage::lib::Distribution> _distribution;
+
+    using StateSnapshot = std::pair<std::shared_ptr<const storage::lib::ClusterState>,
+                                    std::shared_ptr<const storage::lib::Distribution>>;
+
+    // Acquires _lock
+    [[nodiscard]] StateSnapshot internal_state_snapshot();
 
     mbus::Hop getRecipient(mbus::RoutingContext& context, int distributor);
+    // Acquires _lock
+    void updateStateFromReply(WrongDistributionReply& reply);
+    // Acquires _lock
+    void reset_state();
 
 public:
-    ContentPolicy(const string& param);
-    ~ContentPolicy();
+    explicit ContentPolicy(const string& param);
+    ~ContentPolicy() override;
     void doSelect(mbus::RoutingContext &context) override;
     void merge(mbus::RoutingContext &context) override;
 
-    void updateStateFromReply(WrongDistributionReply& reply);
-
     /**
      * @return a pointer to the system state registered with this policy. If
-     * we haven't received a system state yet, returns NULL.
+     * we haven't received a system state yet, returns nullptr.
      */
-    const storage::lib::ClusterState* getSystemState() const { return _state.get(); }
+    std::shared_ptr<const storage::lib::ClusterState> getSystemState() const noexcept;
 
     virtual void configure(std::unique_ptr<storage::lib::Distribution::DistributionConfig> config);
     string init() override;
 
 private:
-    string createConfigId(const string & clusterName) const;
-    string createPattern(const string & clusterName, int distributor) const;
+    static string createConfigId(const string & clusterName);
+    static string createPattern(const string & clusterName, int distributor);
 };
 
 }