feat: Show multiple costs in timelinewidget

Showing only one cost is fine if we only show a hardware event, but
since we now support tracepoints and some come in an enter/exit pair it
requires us to rework the timeline delegate.
This patch makes the event source combobox multi select and allows to
select multiple event sources.

Author: lievenhey

src/models/eventmodelproxy.cpp

@@ -21,6 +21,18 @@ EventModelProxy::EventModelProxy(QObject* parent)
 
 EventModelProxy::~EventModelProxy() = default;
 
+void EventModelProxy::showCostId(qint32 costId)
+{
+    m_hiddenCostIds.remove(costId);
+    invalidate();
+}
+
+void EventModelProxy::hideCostId(qint32 costId)
+{
+    m_hiddenCostIds.insert(costId);
+    invalidate();
+}
+
 bool EventModelProxy::filterAcceptsRow(int source_row, const QModelIndex& source_parent) const
 {
     // index is invalid -> we are at the root node
@@ -36,7 +48,7 @@ bool EventModelProxy::filterAcceptsRow(int source_row, const QModelIndex& source
                     .data(EventModel::EventsRole)
                     .value<Data::Events>();
 
-    if (data.empty()) {
+    if (data.empty() || m_hiddenCostIds.contains(data[0].type)) {
         return false;
     }
 

src/models/eventmodelproxy.h

@@ -7,6 +7,7 @@
 
 #pragma once
 
+#include <QSet>
 #include <QSortFilterProxyModel>
 
 class EventModelProxy : public QSortFilterProxyModel
@@ -16,7 +17,13 @@ class EventModelProxy : public QSortFilterProxyModel
     explicit EventModelProxy(QObject* parent = nullptr);
     ~EventModelProxy() override;
 
+    void showCostId(qint32 costId);
+    void hideCostId(qint32 costId);
+
 protected:
     bool filterAcceptsRow(int source_row, const QModelIndex& source_parent) const override;
     bool lessThan(const QModelIndex& source_left, const QModelIndex& source_right) const override;
+
+private:
+    QSet<qint32> m_hiddenCostIds;
 };

src/models/timelinedelegate.cpp

@@ -161,7 +161,6 @@ void TimeLineDelegate::paint(QPainter* painter, const QStyleOptionViewItem& opti
     const auto results = index.data(EventModel::EventResultsRole).value<Data::EventResults>();
     const auto offCpuCostId = results.offCpuTimeCostId;
     const auto lostEventCostId = results.lostEventCostId;
-    const auto tracepointEventCostId = results.tracepointEventCostId;
     const bool is_alternate = option.features & QStyleOptionViewItem::Alternate;
     const auto& palette = option.palette;
 
@@ -231,10 +230,6 @@ void TimeLineDelegate::paint(QPainter* painter, const QStyleOptionViewItem& opti
         // see also: https://www.spinics.net/lists/linux-perf-users/msg03486.html
         for (const auto& event : data.events) {
             const auto isLostEvent = event.type == lostEventCostId;
-            const auto isTracepointEvent = event.type == tracepointEventCostId;
-            if (event.type != m_eventType && !isLostEvent && !isTracepointEvent) {
-                continue;
-            }
 
             const auto x = data.mapTimeToX(event.time);
             if (x < TimeLineData::padding || x >= data.w) {
@@ -334,14 +329,22 @@ bool TimeLineDelegate::helpEvent(QHelpEvent* event, QAbstractItemView* view, con
                                         Util::formatTimeString(found.totalCost),
                                         Util::formatTimeString(found.maxCost)));
         } else if (found.numSamples > 0) {
-            QToolTip::showText(event->globalPos(),
-                               tr("time: %1\n%5 samples: %2\ntotal sample cost: %3\nmax sample cost: %4")
-                                   .arg(formattedTime, QString::number(found.numSamples),
-                                        Util::formatCost(found.totalCost), Util::formatCost(found.maxCost),
-                                        totalCosts.value(found.type).label));
+            if (m_eventType == results.tracepointEventCostId) {
+                // currently tracepoint cost is saying nothig, so don't show it
+                QToolTip::showText(
+                    event->globalPos(),
+                    tr("time: %1\n%3 samples: %2")
+                        .arg(formattedTime, QString::number(found.numSamples), results.tracepoints[index.row()].name));
+
+            } else {
+                QToolTip::showText(event->globalPos(),
+                                   tr("time: %1\n%5 samples: %2\ntotal sample cost: %3\nmax sample cost: %4")
+                                       .arg(formattedTime, QString::number(found.numSamples),
+                                            Util::formatCost(found.totalCost), Util::formatCost(found.maxCost),
+                                            totalCosts.value(found.type).label));
+            }
         } else {
-            QToolTip::showText(event->globalPos(),
-                               tr("time: %1 (no %2 samples)").arg(formattedTime, totalCosts.value(m_eventType).label));
+            QToolTip::showText(event->globalPos(), tr("time: %1 (no samples)").arg(formattedTime));
         }
         return true;
     }
@@ -390,6 +393,12 @@ bool TimeLineDelegate::eventFilter(QObject* watched, QEvent* event)
 
             const auto time = data.mapXToTime(pos.x() - visualRect.left() - TimeLineData::padding);
             const auto start = findEvent(data.events.constBegin(), data.events.constEnd(), time);
+
+            // we can show multiple events in one row so we need to dynamically figure out which costId is needed
+            auto hoveringEntry = std::find_if(start, data.events.cend(),
+                                              [time](const Data::Event& event) { return event.time >= time; });
+            setEventType(hoveringEntry != data.events.cend() ? hoveringEntry->type : 0);
+
             auto findSamples = [&](int costType, bool contains) {
                 bool foundAny = false;
                 data.findSamples(hoverX, costType, results.lostEventCostId, contains, start,

src/models/timelinedelegate.h

@@ -59,7 +59,6 @@ class TimeLineDelegate : public QStyledItemDelegate
     bool helpEvent(QHelpEvent* event, QAbstractItemView* view, const QStyleOptionViewItem& option,
                    const QModelIndex& index) override;
 
-    void setEventType(int type);
     void setSelectedStacks(const QSet<qint32>& selectedStacks);
 
 signals:
@@ -71,6 +70,7 @@ class TimeLineDelegate : public QStyledItemDelegate
     bool eventFilter(QObject* watched, QEvent* event) override;
 
 private:
+    void setEventType(int type);
     void updateView();
     void updateZoomState();
 

src/resultsutil.cpp

@@ -19,6 +19,8 @@
 #include <QTimer>
 #include <QTreeView>
 
+#include <QStandardItemModel>
+
 #include "models/costdelegate.h"
 #include "models/data.h"
 #include "models/filterandzoomstack.h"
@@ -219,6 +221,36 @@ void fillEventSourceComboBox(QComboBox* combo, const Data::Costs& costs, const Q
     }
 }
 
+void fillEventSourceComboBoxMultiSelect(QComboBox* combo, const Data::Costs& costs, const QString& /*tooltipTemplate*/)
+{
+    // restore selection if possible
+    const auto oldData = combo->currentData();
+
+    combo->clear();
+
+    auto model = new QStandardItemModel(costs.numTypes(), 1, combo);
+    int itemCounter = 0;
+    for (int costId = 0, c = costs.numTypes(); costId < c; costId++) {
+        if (!costs.totalCost(costId)) {
+            continue;
+        }
+
+        auto item = new QStandardItem(costs.typeName(costId));
+        item->setFlags(Qt::ItemIsUserCheckable | Qt::ItemIsEnabled);
+        item->setData(Qt::Checked, Qt::CheckStateRole);
+        item->setData(costId, Qt::UserRole + 1);
+        model->setItem(itemCounter, item);
+        itemCounter++;
+    }
+    model->setRowCount(itemCounter);
+    combo->setModel(model);
+
+    const auto index = combo->findData(oldData);
+    if (index != -1) {
+        combo->setCurrentIndex(index);
+    }
+}
+
 void setupResultsAggregation(QComboBox* costAggregationComboBox)
 {
     struct AggregationType

src/resultsutil.h

@@ -100,6 +100,7 @@ void hideEmptyColumns(const Data::Costs& costs, QTreeView* view, int numBaseColu
 void hideTracepointColumns(const Data::Costs& costs, QTreeView* view, int numBaseColumns);
 
 void fillEventSourceComboBox(QComboBox* combo, const Data::Costs& costs, const QString& tooltipTemplate);
+void fillEventSourceComboBoxMultiSelect(QComboBox* combo, const Data::Costs& costs, const QString& tooltipTemplate);
 
 void setupResultsAggregation(QComboBox* costAggregationComboBox);
 }

src/timelinewidget.cpp

@@ -17,9 +17,11 @@
 #include "parsers/perf/perfparser.h"
 
 #include <QLabel>
+#include <QListView>
 #include <QPointer>
 #include <QProgressBar>
 #include <QSortFilterProxyModel>
+#include <QStandardItemModel>
 #include <QVBoxLayout>
 
 #include <KLocalizedString>
@@ -82,9 +84,24 @@ TimeLineWidget::TimeLineWidget(PerfParser* parser, QMenu* filterMenu, FilterAndZ
     connect(timeLineProxy, &QAbstractItemModel::rowsInserted, this, [this]() { ui->timeLineView->expandToDepth(1); });
     connect(timeLineProxy, &QAbstractItemModel::modelReset, this, [this]() { ui->timeLineView->expandToDepth(1); });
 
-    connect(m_parser, &PerfParser::bottomUpDataAvailable, this, [this](const Data::BottomUpResults& data) {
-        ResultsUtil::fillEventSourceComboBox(ui->timeLineEventSource, data.costs, tr("Show timeline for %1 events."));
-    });
+    connect(m_parser, &PerfParser::bottomUpDataAvailable, this,
+            [this, timeLineProxy](const Data::BottomUpResults& data) {
+                ResultsUtil::fillEventSourceComboBoxMultiSelect(ui->timeLineEventSource, data.costs,
+                                                                tr("Show timeline for %1 events."));
+
+                auto model = qobject_cast<QStandardItemModel*>(ui->timeLineEventSource->model());
+                connect(ui->timeLineEventSource->model(), &QStandardItemModel::dataChanged, model,
+                        [timeLineProxy](const QModelIndex& topLeft, const QModelIndex& /*bottomRight*/,
+                                        const QVector<int>& /*roles*/) {
+                            auto checkState = topLeft.data(Qt::CheckStateRole).value<Qt::CheckState>();
+
+                            if (checkState == Qt::CheckState::Checked) {
+                                timeLineProxy->showCostId(topLeft.data(Qt::UserRole + 1).toUInt());
+                            } else {
+                                timeLineProxy->hideCostId(topLeft.data(Qt::UserRole + 1).toUInt());
+                            }
+                        });
+            });
 
     connect(m_parser, &PerfParser::eventsAvailable, this, [this, eventModel](const Data::EventResults& data) {
         eventModel->setData(data);
@@ -101,12 +118,6 @@ TimeLineWidget::TimeLineWidget(PerfParser* parser, QMenu* filterMenu, FilterAndZ
         }
     });
 
-    connect(ui->timeLineEventSource, static_cast<void (QComboBox::*)(int)>(&QComboBox::currentIndexChanged), this,
-            [this](int index) {
-                const auto typeId = ui->timeLineEventSource->itemData(index).toInt();
-                m_timeLineDelegate->setEventType(typeId);
-            });
-
     connect(m_timeLineDelegate, &TimeLineDelegate::addToFavorites, this,
             [eventModel](const QModelIndex& index) { eventModel->addToFavorites(index); });
     connect(m_timeLineDelegate, &TimeLineDelegate::removeFromFavorites, this,