Merge pull request #7112

9af5f9c Move uiInterface.NotifyBlockTip signal above the core/wallet signal - This will keep getbestblockhash more in sync with blocknotify callbacks (Jonas Schnelli)
4082e46 [Qt] call GuessVerificationProgress synchronous during core signal, pass double over UI signal (Jonas Schnelli)
947d20b [Qt] reduce cs_main in getVerificationProgress() (Jonas Schnelli)
e6d50fc [Qt] update block tip (height and date) without locking cs_main, update always (each block) (Jonas Schnelli)
012fc91 NotifyBlockTip signal: switch from hash (uint256) to CBlockIndex* - also adds a boolean for indication if the tip update was happening during initial sync - emit notification also during initial sync (Jonas Schnelli)

10 files changed, 83 insertions, 80 deletions

diff --git a/src/init.cpp b/src/init.cpp
index 191c2ed8ae..e6ce3d7b59 100644
--- a/src/init.cpp
+++ b/src/init.cpp
@@ -515,11 +515,14 @@ std::string LicenseInfo()
            "\n";
 }
 
-static void BlockNotifyCallback(const uint256& hashNewTip)
+static void BlockNotifyCallback(bool initialSync, const CBlockIndex *pBlockIndex)
 {
+    if (initialSync || !pBlockIndex)
+        return;
+
     std::string strCmd = GetArg("-blocknotify", "");
 
-    boost::replace_all(strCmd, "%s", hashNewTip.GetHex());
+    boost::replace_all(strCmd, "%s", pBlockIndex->GetBlockHash().GetHex());
     boost::thread t(runCommand, strCmd); // thread runs free
 }
 
diff --git a/src/main.cpp b/src/main.cpp
index 901a34bdec..33bd2e0ce1 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -2606,37 +2606,41 @@ bool ActivateBestChain(CValidationState &state, const CChainParams& chainparams,
         // When we reach this point, we switched to a new tip (stored in pindexNewTip).
 
         // Notifications/callbacks that can run without cs_main
-        if (!fInitialDownload) {
-            // Find the hashes of all blocks that weren't previously in the best chain.
-            std::vector<uint256> vHashes;
-            CBlockIndex *pindexToAnnounce = pindexNewTip;
-            while (pindexToAnnounce != pindexFork) {
-                vHashes.push_back(pindexToAnnounce->GetBlockHash());
-                pindexToAnnounce = pindexToAnnounce->pprev;
-                if (vHashes.size() == MAX_BLOCKS_TO_ANNOUNCE) {
-                    // Limit announcements in case of a huge reorganization.
-                    // Rely on the peer's synchronization mechanism in that case.
-                    break;
+        // Always notify the UI if a new block tip was connected
+        if (pindexFork != pindexNewTip) {
+            uiInterface.NotifyBlockTip(fInitialDownload, pindexNewTip);
+
+            if (!fInitialDownload) {
+                // Find the hashes of all blocks that weren't previously in the best chain.
+                std::vector<uint256> vHashes;
+                CBlockIndex *pindexToAnnounce = pindexNewTip;
+                while (pindexToAnnounce != pindexFork) {
+                    vHashes.push_back(pindexToAnnounce->GetBlockHash());
+                    pindexToAnnounce = pindexToAnnounce->pprev;
+                    if (vHashes.size() == MAX_BLOCKS_TO_ANNOUNCE) {
+                        // Limit announcements in case of a huge reorganization.
+                        // Rely on the peer's synchronization mechanism in that case.
+                        break;
+                    }
                 }
-            }
-            // Relay inventory, but don't relay old inventory during initial block download.
-            int nBlockEstimate = 0;
-            if (fCheckpointsEnabled)
-                nBlockEstimate = Checkpoints::GetTotalBlocksEstimate(chainparams.Checkpoints());
-            {
-                LOCK(cs_vNodes);
-                BOOST_FOREACH(CNode* pnode, vNodes) {
-                    if (chainActive.Height() > (pnode->nStartingHeight != -1 ? pnode->nStartingHeight - 2000 : nBlockEstimate)) {
-                        BOOST_REVERSE_FOREACH(const uint256& hash, vHashes) {
-                            pnode->PushBlockHash(hash);
+                // Relay inventory, but don't relay old inventory during initial block download.
+                int nBlockEstimate = 0;
+                if (fCheckpointsEnabled)
+                    nBlockEstimate = Checkpoints::GetTotalBlocksEstimate(chainparams.Checkpoints());
+                {
+                    LOCK(cs_vNodes);
+                    BOOST_FOREACH(CNode* pnode, vNodes) {
+                        if (chainActive.Height() > (pnode->nStartingHeight != -1 ? pnode->nStartingHeight - 2000 : nBlockEstimate)) {
+                            BOOST_REVERSE_FOREACH(const uint256& hash, vHashes) {
+                                pnode->PushBlockHash(hash);
+                            }
                         }
                     }
                 }
-            }
-            // Notify external listeners about the new tip.
-            if (!vHashes.empty()) {
-                GetMainSignals().UpdatedBlockTip(pindexNewTip);
-                uiInterface.NotifyBlockTip(vHashes.front());
+                // Notify external listeners about the new tip.
+                if (!vHashes.empty()) {
+                    GetMainSignals().UpdatedBlockTip(pindexNewTip);
+                }
             }
         }
     } while(pindexMostWork != chainActive.Tip());
diff --git a/src/qt/bitcoingui.cpp b/src/qt/bitcoingui.cpp
index 853a29e661..b2bd167aea 100644
--- a/src/qt/bitcoingui.cpp
+++ b/src/qt/bitcoingui.cpp
@@ -453,8 +453,8 @@ void BitcoinGUI::setClientModel(ClientModel *clientModel)
         setNumConnections(clientModel->getNumConnections());
         connect(clientModel, SIGNAL(numConnectionsChanged(int)), this, SLOT(setNumConnections(int)));
 
-        setNumBlocks(clientModel->getNumBlocks(), clientModel->getLastBlockDate());
-        connect(clientModel, SIGNAL(numBlocksChanged(int,QDateTime)), this, SLOT(setNumBlocks(int,QDateTime)));
+        setNumBlocks(clientModel->getNumBlocks(), clientModel->getLastBlockDate(), clientModel->getVerificationProgress(NULL));
+        connect(clientModel, SIGNAL(numBlocksChanged(int,QDateTime,double)), this, SLOT(setNumBlocks(int,QDateTime,double)));
 
         // Receive and report messages from client model
         connect(clientModel, SIGNAL(message(QString,QString,unsigned int)), this, SLOT(message(QString,QString,unsigned int)));
@@ -682,7 +682,7 @@ void BitcoinGUI::setNumConnections(int count)
     labelConnectionsIcon->setToolTip(tr("%n active connection(s) to Bitcoin network", "", count));
 }
 
-void BitcoinGUI::setNumBlocks(int count, const QDateTime& blockDate)
+void BitcoinGUI::setNumBlocks(int count, const QDateTime& blockDate, double nVerificationProgress)
 {
     if(!clientModel)
         return;
@@ -759,7 +759,7 @@ void BitcoinGUI::setNumBlocks(int count, const QDateTime& blockDate)
         progressBarLabel->setVisible(true);
         progressBar->setFormat(tr("%1 behind").arg(timeBehindText));
         progressBar->setMaximum(1000000000);
-        progressBar->setValue(clientModel->getVerificationProgress() * 1000000000.0 + 0.5);
+        progressBar->setValue(nVerificationProgress * 1000000000.0 + 0.5);
         progressBar->setVisible(true);
 
         tooltip = tr("Catching up...") + QString("<br>") + tooltip;
diff --git a/src/qt/bitcoingui.h b/src/qt/bitcoingui.h
index 945adcd459..b121a443e7 100644
--- a/src/qt/bitcoingui.h
+++ b/src/qt/bitcoingui.h
@@ -150,7 +150,7 @@ public Q_SLOTS:
     /** Set number of connections shown in the UI */
     void setNumConnections(int count);
     /** Set number of blocks and last block date shown in the UI */
-    void setNumBlocks(int count, const QDateTime& blockDate);
+    void setNumBlocks(int count, const QDateTime& blockDate, double nVerificationProgress);
 
     /** Notify the user of an event from the core network or transaction handling code.
        @param[in] title     the message box / notification title
diff --git a/src/qt/clientmodel.cpp b/src/qt/clientmodel.cpp
index 566e8fa62d..d36d129c1a 100644
--- a/src/qt/clientmodel.cpp
+++ b/src/qt/clientmodel.cpp
@@ -22,17 +22,16 @@
 #include <QDebug>
 #include <QTimer>
 
+class CBlockIndex;
+
 static const int64_t nClientStartupTime = GetTime();
+static int64_t nLastBlockTipUpdateNotification = 0;
 
 ClientModel::ClientModel(OptionsModel *optionsModel, QObject *parent) :
     QObject(parent),
     optionsModel(optionsModel),
     peerTableModel(0),
     banTableModel(0),
-    cachedNumBlocks(0),
-    cachedBlockDate(QDateTime()),
-    cachedReindexing(0),
-    cachedImporting(0),
     pollTimer(0)
 {
     peerTableModel = new PeerTableModel(this);
@@ -99,40 +98,21 @@ size_t ClientModel::getMempoolDynamicUsage() const
     return mempool.DynamicMemoryUsage();
 }
 
-double ClientModel::getVerificationProgress() const
+double ClientModel::getVerificationProgress(const CBlockIndex *tipIn) const
 {
-    LOCK(cs_main);
-    return Checkpoints::GuessVerificationProgress(Params().Checkpoints(), chainActive.Tip());
+    CBlockIndex *tip = const_cast<CBlockIndex *>(tipIn);
+    if (!tip)
+    {
+        LOCK(cs_main);
+        tip = chainActive.Tip();
+    }
+    return Checkpoints::GuessVerificationProgress(Params().Checkpoints(), tip);
 }
 
 void ClientModel::updateTimer()
 {
-    // Get required lock upfront. This avoids the GUI from getting stuck on
-    // periodical polls if the core is holding the locks for a longer time -
-    // for example, during a wallet rescan.
-    TRY_LOCK(cs_main, lockMain);
-    if (!lockMain)
-        return;
-
-    // Some quantities (such as number of blocks) change so fast that we don't want to be notified for each change.
-    // Periodically check and update with a timer.
-    int newNumBlocks = getNumBlocks();
-    QDateTime newBlockDate = getLastBlockDate();
-
-    // check for changed number of blocks we have, number of blocks peers claim to have, reindexing state and importing state
-    if (cachedNumBlocks != newNumBlocks ||
-        cachedBlockDate != newBlockDate ||
-        cachedReindexing != fReindex ||
-        cachedImporting != fImporting)
-    {
-        cachedNumBlocks = newNumBlocks;
-        cachedBlockDate = newBlockDate;
-        cachedReindexing = fReindex;
-        cachedImporting = fImporting;
-
-        Q_EMIT numBlocksChanged(newNumBlocks, newBlockDate);
-    }
-
+    // no locking required at this point
+    // the following calls will aquire the required lock
     Q_EMIT mempoolSizeChanged(getMempoolSize(), getMempoolDynamicUsage());
     Q_EMIT bytesChanged(getTotalBytesRecv(), getTotalBytesSent());
 }
@@ -261,6 +241,23 @@ static void BannedListChanged(ClientModel *clientmodel)
     QMetaObject::invokeMethod(clientmodel, "updateBanlist", Qt::QueuedConnection);
 }
 
+static void BlockTipChanged(ClientModel *clientmodel, bool initialSync, const CBlockIndex *pIndex)
+{
+    // lock free async UI updates in case we have a new block tip
+    // during initial sync, only update the UI if the last update
+    // was > 250ms (MODEL_UPDATE_DELAY) ago
+    int64_t now = 0;
+    if (initialSync)
+        now = GetTimeMillis();
+
+    // if we are in-sync, update the UI regardless of last update time
+    if (!initialSync || now - nLastBlockTipUpdateNotification > MODEL_UPDATE_DELAY) {
+        //pass a async signal to the UI thread
+        Q_EMIT clientmodel->numBlocksChanged(pIndex->nHeight, QDateTime::fromTime_t(pIndex->GetBlockTime()), clientmodel->getVerificationProgress(pIndex));
+        nLastBlockTipUpdateNotification = now;
+    }
+}
+
 void ClientModel::subscribeToCoreSignals()
 {
     // Connect signals to client
@@ -268,6 +265,7 @@ void ClientModel::subscribeToCoreSignals()
     uiInterface.NotifyNumConnectionsChanged.connect(boost::bind(NotifyNumConnectionsChanged, this, _1));
     uiInterface.NotifyAlertChanged.connect(boost::bind(NotifyAlertChanged, this, _1, _2));
     uiInterface.BannedListChanged.connect(boost::bind(BannedListChanged, this));
+    uiInterface.NotifyBlockTip.connect(boost::bind(BlockTipChanged, this, _1, _2));
 }
 
 void ClientModel::unsubscribeFromCoreSignals()
@@ -277,4 +275,5 @@ void ClientModel::unsubscribeFromCoreSignals()
     uiInterface.NotifyNumConnectionsChanged.disconnect(boost::bind(NotifyNumConnectionsChanged, this, _1));
     uiInterface.NotifyAlertChanged.disconnect(boost::bind(NotifyAlertChanged, this, _1, _2));
     uiInterface.BannedListChanged.disconnect(boost::bind(BannedListChanged, this));
+    uiInterface.NotifyBlockTip.disconnect(boost::bind(BlockTipChanged, this, _1, _2));
 }
diff --git a/src/qt/clientmodel.h b/src/qt/clientmodel.h
index 493a759331..2d204fdb67 100644
--- a/src/qt/clientmodel.h
+++ b/src/qt/clientmodel.h
@@ -15,6 +15,7 @@ class PeerTableModel;
 class TransactionTableModel;
 
 class CWallet;
+class CBlockIndex;
 
 QT_BEGIN_NAMESPACE
 class QTimer;
@@ -59,7 +60,7 @@ public:
     quint64 getTotalBytesRecv() const;
     quint64 getTotalBytesSent() const;
 
-    double getVerificationProgress() const;
+    double getVerificationProgress(const CBlockIndex *tip) const;
     QDateTime getLastBlockDate() const;
 
     //! Return true if core is doing initial block download
@@ -81,11 +82,6 @@ private:
     PeerTableModel *peerTableModel;
     BanTableModel *banTableModel;
 
-    int cachedNumBlocks;
-    QDateTime cachedBlockDate;
-    bool cachedReindexing;
-    bool cachedImporting;
-
     QTimer *pollTimer;
 
     void subscribeToCoreSignals();
@@ -93,7 +89,7 @@ private:
 
 Q_SIGNALS:
     void numConnectionsChanged(int count);
-    void numBlocksChanged(int count, const QDateTime& blockDate);
+    void numBlocksChanged(int count, const QDateTime& blockDate, double nVerificationProgress);
     void mempoolSizeChanged(long count, size_t mempoolSizeInBytes);
     void alertsChanged(const QString &warnings);
     void bytesChanged(quint64 totalBytesIn, quint64 totalBytesOut);
diff --git a/src/qt/rpcconsole.cpp b/src/qt/rpcconsole.cpp
index b2b4fd0fab..30e551de19 100644
--- a/src/qt/rpcconsole.cpp
+++ b/src/qt/rpcconsole.cpp
@@ -343,8 +343,8 @@ void RPCConsole::setClientModel(ClientModel *model)
         setNumConnections(model->getNumConnections());
         connect(model, SIGNAL(numConnectionsChanged(int)), this, SLOT(setNumConnections(int)));
 
-        setNumBlocks(model->getNumBlocks(), model->getLastBlockDate());
-        connect(model, SIGNAL(numBlocksChanged(int,QDateTime)), this, SLOT(setNumBlocks(int,QDateTime)));
+        setNumBlocks(model->getNumBlocks(), model->getLastBlockDate(), model->getVerificationProgress(NULL));
+        connect(model, SIGNAL(numBlocksChanged(int,QDateTime,double)), this, SLOT(setNumBlocks(int,QDateTime,double)));
 
         updateTrafficStats(model->getTotalBytesRecv(), model->getTotalBytesSent());
         connect(model, SIGNAL(bytesChanged(quint64,quint64)), this, SLOT(updateTrafficStats(quint64, quint64)));
@@ -525,7 +525,7 @@ void RPCConsole::setNumConnections(int count)
     ui->numberOfConnections->setText(connections);
 }
 
-void RPCConsole::setNumBlocks(int count, const QDateTime& blockDate)
+void RPCConsole::setNumBlocks(int count, const QDateTime& blockDate, double nVerificationProgress)
 {
     ui->numberOfBlocks->setText(QString::number(count));
     ui->lastBlockTime->setText(blockDate.toString());
diff --git a/src/qt/rpcconsole.h b/src/qt/rpcconsole.h
index 4b242affcd..4aebad480c 100644
--- a/src/qt/rpcconsole.h
+++ b/src/qt/rpcconsole.h
@@ -83,7 +83,7 @@ public Q_SLOTS:
     /** Set number of connections shown in the UI */
     void setNumConnections(int count);
     /** Set number of blocks and last block date shown in the UI */
-    void setNumBlocks(int count, const QDateTime& blockDate);
+    void setNumBlocks(int count, const QDateTime& blockDate, double nVerificationProgress);
     /** Set size (number of transactions and memory usage) of the mempool in the UI */
     void setMempoolSize(long numberOfTxs, size_t dynUsage);
     /** Go forward or back in history */
diff --git a/src/qt/sendcoinsdialog.cpp b/src/qt/sendcoinsdialog.cpp
index 7b714be5b1..0fd86da034 100644
--- a/src/qt/sendcoinsdialog.cpp
+++ b/src/qt/sendcoinsdialog.cpp
@@ -124,7 +124,7 @@ void SendCoinsDialog::setClientModel(ClientModel *clientModel)
     this->clientModel = clientModel;
 
     if (clientModel) {
-        connect(clientModel, SIGNAL(numBlocksChanged(int,QDateTime)), this, SLOT(updateSmartFeeLabel()));
+        connect(clientModel, SIGNAL(numBlocksChanged(int,QDateTime,double)), this, SLOT(updateSmartFeeLabel()));
     }
 }
 
diff --git a/src/ui_interface.h b/src/ui_interface.h
index e402479933..00d9303124 100644
--- a/src/ui_interface.h
+++ b/src/ui_interface.h
@@ -15,6 +15,7 @@
 class CBasicKeyStore;
 class CWallet;
 class uint256;
+class CBlockIndex;
 
 /** General change type (added, updated, removed). */
 enum ChangeType
@@ -94,7 +95,7 @@ public:
     boost::signals2::signal<void (const std::string &title, int nProgress)> ShowProgress;
 
     /** New block has been accepted */
-    boost::signals2::signal<void (const uint256& hash)> NotifyBlockTip;
+    boost::signals2::signal<void (bool, const CBlockIndex *)> NotifyBlockTip;
 
     /** Banlist did change. */
     boost::signals2::signal<void (void)> BannedListChanged;