Implemented SR transaction rollbacking during configuration changes.

SR tranasctions are BF aborted or rolled back on primary view
changes according to the following rules:
* Ongoing local SR transactions are BF aborted if the processing
  server is not found from the current view.
* All remote SR transactions whose origin server is not included in the
  current view are rolled back.

src/server_state.cpp

@@ -3,6 +3,7 @@
 //
 
 #include "wsrep/server_state.hpp"
+#include "wsrep/client_state.hpp"
 #include "wsrep/server_service.hpp"
 #include "wsrep/high_priority_service.hpp"
 #include "wsrep/transaction.hpp"
@@ -13,6 +14,7 @@
 
 #include <cassert>
 #include <sstream>
+#include <algorithm>
 
 //////////////////////////////////////////////////////////////////////////////
 //                               Helpers                                    //
@@ -504,19 +506,6 @@ void wsrep::server_state::initialized()
     }
 }
 
-void wsrep::server_state::wait_until_state(
-    wsrep::unique_lock<wsrep::mutex>& lock,
-    enum wsrep::server_state::state state) const
-{
-    ++state_waiters_[state];
-    while (state_ != state)
-    {
-        cond_.wait(lock);
-    }
-    --state_waiters_[state];
-    cond_.notify_all();
-}
-
 void wsrep::server_state::last_committed_gtid(const wsrep::gtid& gtid)
 {
     wsrep::unique_lock<wsrep::mutex> lock(mutex_);
@@ -556,7 +545,8 @@ void wsrep::server_state::on_connect(const wsrep::gtid& gtid)
     state(lock, s_connected);
 }
 
-void wsrep::server_state::on_view(const wsrep::view& view)
+void wsrep::server_state::on_view(const wsrep::view& view,
+                                  wsrep::high_priority_service* high_priority_service)
 {
     wsrep::log_info()
         << "================================================\nView:\n"
@@ -644,6 +634,11 @@ void wsrep::server_state::on_view(const wsrep::view& view)
             bootstrap_ = false;
         }
 
+        assert(high_priority_service);
+        if (high_priority_service)
+        {
+            close_foreign_sr_transactions(lock, *high_priority_service);
+        }
         if (server_service_.sst_before_init())
         {
             if (state_ == s_initialized)
@@ -756,11 +751,85 @@ int wsrep::server_state::on_apply(
     }
 }
 
+void wsrep::server_state::start_streaming_client(
+    wsrep::client_state* client_state)
+{
+    wsrep::unique_lock<wsrep::mutex> lock(mutex_);
+    wsrep::log_debug() << "Start streaming client: " << client_state->id();
+    if (streaming_clients_.insert(
+            std::make_pair(client_state->id(), client_state)).second == false)
+    {
+        wsrep::log_warning() << "Failed to insert streaming client "
+                             << client_state->id();
+        assert(0);
+    }
+}
+
+void wsrep::server_state::convert_streaming_client_to_applier(
+    wsrep::client_state* client_state)
+{
+    wsrep::unique_lock<wsrep::mutex> lock(mutex_);
+    wsrep::log_debug() << "Convert streaming client to applier "
+                       << client_state->id();
+    streaming_clients_map::iterator i(
+        streaming_clients_.find(client_state->id()));
+    assert(i != streaming_clients_.end());
+    if (i == streaming_clients_.end())
+    {
+        wsrep::log_warning() << "Unable to find streaming client "
+                             << client_state->id();
+        assert(0);
+    }
+    else
+    {
+        streaming_clients_.erase(i);
+    }
+    wsrep::high_priority_service* streaming_applier(
+        server_service_.streaming_applier_service(
+            client_state->client_service()));
+    streaming_applier->adopt_transaction(client_state->transaction());
+    if (streaming_appliers_.insert(
+            std::make_pair(
+                std::make_pair(id_, client_state->transaction().id()),
+                streaming_applier)).second == false)
+    {
+        wsrep::log_warning() << "Could not insert streaming applier "
+                             << id_
+                             << ", "
+                             << client_state->transaction().id();
+        assert(0);
+    }
+}
+
+
+void wsrep::server_state::stop_streaming_client(
+    wsrep::client_state* client_state)
+{
+    wsrep::unique_lock<wsrep::mutex> lock(mutex_);
+    wsrep::log_debug() << "Stop streaming client: " << client_state->id();
+    streaming_clients_map::iterator i(
+        streaming_clients_.find(client_state->id()));
+    assert(i != streaming_clients_.end());
+    if (i == streaming_clients_.end())
+    {
+        wsrep::log_warning() << "Unable to find streaming client "
+                             << client_state->id();
+        assert(0);
+        return;
+    }
+    else
+    {
+        streaming_clients_.erase(i);
+        cond_.notify_all();
+    }
+}
+
 void wsrep::server_state::start_streaming_applier(
     const wsrep::id& server_id,
     const wsrep::transaction_id& transaction_id,
     wsrep::high_priority_service* sa)
 {
+    wsrep::unique_lock<wsrep::mutex> lock(mutex_);
     if (streaming_appliers_.insert(
             std::make_pair(std::make_pair(server_id, transaction_id),
                            sa)).second == false)
@@ -774,6 +843,7 @@ void wsrep::server_state::stop_streaming_applier(
     const wsrep::id& server_id,
     const wsrep::transaction_id& transaction_id)
 {
+    wsrep::unique_lock<wsrep::mutex> lock(mutex_);
     streaming_appliers_map::iterator i(
         streaming_appliers_.find(std::make_pair(server_id, transaction_id)));
     assert(i != streaming_appliers_.end());
@@ -785,6 +855,7 @@ void wsrep::server_state::stop_streaming_applier(
     else
     {
         streaming_appliers_.erase(i);
+        cond_.notify_all();
     }
 }
 
@@ -792,13 +863,15 @@ wsrep::high_priority_service* wsrep::server_state::find_streaming_applier(
     const wsrep::id& server_id,
     const wsrep::transaction_id& transaction_id) const
 {
+    wsrep::unique_lock<wsrep::mutex> lock(mutex_);
     streaming_appliers_map::const_iterator i(
         streaming_appliers_.find(std::make_pair(server_id, transaction_id)));
     return (i == streaming_appliers_.end() ? 0 : i->second);
 }
 
-// Private
-
+//////////////////////////////////////////////////////////////////////////////
+//                              Private                                     //
+//////////////////////////////////////////////////////////////////////////////
 
 int wsrep::server_state::desync(wsrep::unique_lock<wsrep::mutex>& lock)
 {
@@ -869,3 +942,79 @@ void wsrep::server_state::state(
         // throw wsrep::runtime_error(os.str());
     }
 }
+
+void wsrep::server_state::wait_until_state(
+    wsrep::unique_lock<wsrep::mutex>& lock,
+    enum wsrep::server_state::state state) const
+{
+    ++state_waiters_[state];
+    while (state_ != state)
+    {
+        cond_.wait(lock);
+    }
+    --state_waiters_[state];
+    cond_.notify_all();
+}
+
+void wsrep::server_state::close_foreign_sr_transactions(
+    wsrep::unique_lock<wsrep::mutex>& lock,
+    wsrep::high_priority_service& high_priority_service)
+{
+    assert(lock.owns_lock());
+    if (current_view_.own_index() == -1)
+    {
+        while (streaming_clients_.empty() == false)
+        {
+            streaming_clients_map::iterator i(streaming_clients_.begin());
+            wsrep::client_id client_id(i->first);
+            wsrep::transaction_id transaction_id(i->second->transaction().id());
+            i->second->total_order_bf_abort(current_view_.view_seqno());
+            streaming_clients_map::const_iterator found_i;
+            while ((found_i = streaming_clients_.find(client_id)) !=
+                   streaming_clients_.end() &&
+                   found_i->second->transaction().id() == transaction_id)
+            {
+                cond_.wait(lock);
+            }
+        }
+    }
+
+
+    streaming_appliers_map::iterator i(streaming_appliers_.begin());
+    while (i != streaming_appliers_.end())
+    {
+        if (std::find_if(current_view_.members().begin(),
+                         current_view_.members().end(),
+                         server_id_cmp(i->first.first)) !=
+            current_view_.members().end())
+        {
+            wsrep::id server_id(i->first.first);
+            wsrep::transaction_id transaction_id(i->first.second);
+            wsrep::high_priority_service* streaming_applier(i->second);
+            high_priority_service.adopt_transaction(
+                streaming_applier->transaction());
+            {
+                wsrep::high_priority_switch sw(high_priority_service,
+                                               *streaming_applier);
+                streaming_applier->rollback(
+                    wsrep::ws_handle(), wsrep::ws_meta());
+                streaming_applier->after_apply();
+            }
+
+            streaming_appliers_.erase(i++);
+            server_service_.release_high_priority_service(streaming_applier);
+            wsrep::ws_meta ws_meta(
+                wsrep::gtid(),
+                wsrep::stid(server_id, transaction_id, wsrep::client_id()),
+                wsrep::seqno::undefined(), 0);
+            high_priority_service.remove_fragments(ws_meta);
+            high_priority_service.commit(wsrep::ws_handle(transaction_id, 0),
+                                         ws_meta);
+            high_priority_service.after_apply();
+        }
+        else
+        {
+            ++i;
+        }
+    }
+}

src/transaction.cpp

@@ -477,6 +477,10 @@ int wsrep::transaction::after_commit()
     {
         assert(client_state_.mode() == wsrep::client_state::m_local ||
                client_state_.mode() == wsrep::client_state::m_high_priority);
+        if (client_state_.mode() == wsrep::client_state::m_local)
+        {
+            client_state_.server_state_.stop_streaming_client(&client_state_);
+        }
         clear_fragments();
     }
 
@@ -522,7 +526,7 @@ int wsrep::transaction::before_rollback()
             // fall through
         case s_executing:
             // Voluntary rollback
-            if (is_streaming() && bf_aborted_in_total_order_ == false)
+            if (is_streaming())
             {
                 streaming_rollback();
             }
@@ -535,7 +539,7 @@ int wsrep::transaction::before_rollback()
             }
             else
             {
-                if (is_streaming() && bf_aborted_in_total_order_ == false)
+                if (is_streaming())
                 {
                     streaming_rollback();
                 }
@@ -543,14 +547,14 @@ int wsrep::transaction::before_rollback()
             }
             break;
         case s_cert_failed:
-            if (is_streaming() && bf_aborted_in_total_order_ == false)
+            if (is_streaming())
             {
                 streaming_rollback();
             }
             state(lock, s_aborting);
             break;
         case s_aborting:
-            if (is_streaming() && bf_aborted_in_total_order_ == false)
+            if (is_streaming())
             {
                 streaming_rollback();
             }
@@ -653,8 +657,16 @@ int wsrep::transaction::after_statement()
     case s_must_replay:
     {
         state(lock, s_replaying);
+        // Need to remember streaming state before replay, entering
+        // after_commit() after succesful replay will clear
+        // fragments.
+        const bool was_streaming(is_streaming());
         lock.unlock();
         enum wsrep::provider::status replay_ret(client_service_.replay());
+        if (was_streaming)
+        {
+            client_state_.server_state_.stop_streaming_client(&client_state_);
+        }
         switch (replay_ret)
         {
         case wsrep::provider::success:
@@ -961,6 +973,10 @@ int wsrep::transaction::certify_fragment(
         return 1;
     }
 
+    if (is_streaming() == false)
+    {
+        client_state_.server_state_.start_streaming_client(&client_state_);
+    }
     int ret(0);
     // Storage service scope
     {
@@ -1033,6 +1049,10 @@ int wsrep::transaction::certify_fragment(
     lock.lock();
     if (ret)
     {
+        if (is_streaming() == false)
+        {
+            client_state_.server_state_.stop_streaming_client(&client_state_);
+        }
         if (state_ != s_must_abort)
         {
             state(lock, s_must_abort);
@@ -1246,25 +1266,29 @@ void wsrep::transaction::streaming_rollback()
     debug_log_state("streaming_rollback enter");
     assert(state_ != s_must_replay);
     assert(streaming_context_.rolled_back() == false);
-    // Create a high priority applier which will handle the
-    // rollback fragment or clean up on configuration change.
-    // Adopt transaction will copy fragment set and appropriate
-    // meta data. Mark current transaction streaming context
-    // rolled back.
-    wsrep::high_priority_service* sa(
-        server_service_.streaming_applier_service(
-            client_state_.client_service()));
-    client_state_.server_state().start_streaming_applier(
-        client_state_.server_state().id(), id(), sa);
-    sa->adopt_transaction(*this);
-    streaming_context_.cleanup();
-    streaming_context_.rolled_back(id_);
-    client_service_.debug_sync("wsrep_before_SR_rollback");
-    enum wsrep::provider::status ret;
-    if ((ret = provider().rollback(id_)))
+
+    if (bf_aborted_in_total_order_)
     {
-        wsrep::log_warning() << "Failed to replicate rollback fragment for "
-                             << id_ << ": " << ret;
+        client_state_.server_state_.stop_streaming_client(&client_state_);
+    }
+    else
+    {
+        // Create a high priority applier which will handle the
+        // rollback fragment or clean up on configuration change.
+        // Adopt transaction will copy fragment set and appropriate
+        // meta data. Mark current transaction streaming context
+        // rolled back.
+        client_state_.server_state_.convert_streaming_client_to_applier(
+            &client_state_);
+        streaming_context_.cleanup();
+        streaming_context_.rolled_back(id_);
+        client_service_.debug_sync("wsrep_before_SR_rollback");
+        enum wsrep::provider::status ret;
+        if ((ret = provider().rollback(id_)))
+        {
+            wsrep::log_warning() << "Failed to replicate rollback fragment for "
+                                 << id_ << ": " << ret;
+        }
     }
     debug_log_state("streaming_rollback leave");
 }

src/wsrep_provider_v26.cpp

@@ -306,7 +306,7 @@ namespace
     }
 
     wsrep_cb_status_t view_cb(void* app_ctx,
-                              void* recv_ctx __attribute__((unused)),
+                              void* recv_ctx,
                               const wsrep_view_info_t* view_info,
                               const char*,
                               size_t)
@@ -315,10 +315,12 @@ namespace
         assert(view_info);
         wsrep::server_state& server_state(
             *reinterpret_cast<wsrep::server_state*>(app_ctx));
+        wsrep::high_priority_service* high_priority_service(
+            reinterpret_cast<wsrep::high_priority_service*>(recv_ctx));
         try
         {
             wsrep::view view(view_from_native(*view_info));
-            server_state.on_view(view);
+            server_state.on_view(view, high_priority_service);
             return WSREP_CB_SUCCESS;
         }
         catch (const wsrep::runtime_error& e)