From 5b9df9bae428bcdd2839bebcbd93dc48d6aa6964 Mon Sep 17 00:00:00 2001
From: Pascal Muetschard <pmuetschard@google.com>
Date: Tue, 23 Jul 2019 05:06:12 -0700
Subject: [PATCH] Fix handling of CPU/CPU Frequency track presence.

- Don't crash if no CPU tracks are present
- Don't assume the presence of CPU frequency tracks
---
 .../gapid/perfetto/models/CpuTrack.java       | 16 +++++++++--
 .../google/gapid/perfetto/models/Tracks.java  | 28 ++++++++++++++-----
 2 files changed, 35 insertions(+), 9 deletions(-)

diff --git a/gapic/src/main/com/google/gapid/perfetto/models/CpuTrack.java b/gapic/src/main/com/google/gapid/perfetto/models/CpuTrack.java
index 3045f78d0b..3dfcf590c2 100644
--- a/gapic/src/main/com/google/gapid/perfetto/models/CpuTrack.java
+++ b/gapic/src/main/com/google/gapid/perfetto/models/CpuTrack.java
@@ -146,9 +146,10 @@ private static String sliceRangeSql(int cpu, TimeSpan ts) {
     return format(SLICE_RANGE_SQL, cpu, ts.end, ts.start);
   }
 
-  public static ListenableFuture<Perfetto.Data.Builder> enumerate(
+  public static ListenableFuture<List<CpuConfig>> enumerate(
       String parent, Perfetto.Data.Builder data) {
     return transform(freqMap(data.qe), freqMap -> {
+      List<CpuConfig> configs = Lists.newArrayList();
       for (int i = 0; i < data.getNumCpus(); i++) {
         QueryEngine.Row freq = freqMap.get(Long.valueOf(i));
         CpuTrack track = new CpuTrack(i);
@@ -161,8 +162,9 @@ public static ListenableFuture<Perfetto.Data.Builder> enumerate(
               parent, freqTrack.getId(), "CPU " + (i + 1) + " Frequency",
               single(state -> new CpuFrequencyPanel(state, freqTrack), false));
         }
+        configs.add(new CpuConfig(i, freq != null));
       }
-      return data;
+      return configs;
     });
   }
 
@@ -170,6 +172,16 @@ private static ListenableFuture<Map<Long, QueryEngine.Row>> freqMap(QueryEngine
     return transform(qe.query(FREQ_IDLE_QUERY), res -> res.map(row -> row.getLong(0), identity()));
   }
 
+  public static class CpuConfig {
+    public final int id;
+    public final boolean hasFrequency;
+
+    public CpuConfig(int id, boolean hasFrequency) {
+      this.id = id;
+      this.hasFrequency = hasFrequency;
+    }
+  }
+
   public static class Data extends Track.Data {
     public final Kind kind;
     // Summary.
diff --git a/gapic/src/main/com/google/gapid/perfetto/models/Tracks.java b/gapic/src/main/com/google/gapid/perfetto/models/Tracks.java
index dcedc54311..27a35a9e34 100644
--- a/gapic/src/main/com/google/gapid/perfetto/models/Tracks.java
+++ b/gapic/src/main/com/google/gapid/perfetto/models/Tracks.java
@@ -21,9 +21,11 @@
 import static com.google.gapid.util.MoreFutures.transformAsync;
 
 import com.google.common.collect.Lists;
+import com.google.common.util.concurrent.Futures;
 import com.google.common.util.concurrent.ListenableFuture;
 import com.google.gapid.models.Perfetto;
 import com.google.gapid.perfetto.canvas.Panel;
+import com.google.gapid.perfetto.models.TrackConfig.Group;
 import com.google.gapid.perfetto.views.CounterPanel;
 import com.google.gapid.perfetto.views.CpuSummaryPanel;
 import com.google.gapid.perfetto.views.ProcessSummaryPanel;
@@ -55,14 +57,26 @@ public static ListenableFuture<Perfetto.Data.Builder> enumerate(Perfetto.Data.Bu
   }
 
   private static ListenableFuture<Perfetto.Data.Builder> enumerateCpu(Perfetto.Data.Builder data) {
+    if (data.getNumCpus() == 0) {
+      return Futures.immediateFuture(data);
+    }
+
     CpuSummaryTrack summary = new CpuSummaryTrack(data.getNumCpus());
-    data.tracks.addLabelGroup(null, summary.getId(), "CPU Usage",
-        group(state -> new CpuSummaryPanel(state, summary), false, (group, filtered) -> {
-          for (int i = 1; i < group.size(); i += 2) {
-            group.setVisible(i, !filtered);
-          }
-        }, true));
-    return CpuTrack.enumerate(summary.getId(), data);
+    return transform(CpuTrack.enumerate(summary.getId(), data), configs -> {
+      boolean hasAnyFrequency = configs.stream().anyMatch(c -> c.hasFrequency);
+      Group.UiFactory ui = hasAnyFrequency ?
+          group(state -> new CpuSummaryPanel(state, summary), false, (group, filtered) -> {
+              for (int cpu = 0, track = 0; cpu < configs.size(); cpu++, track++) {
+                if (configs.get(cpu).hasFrequency) {
+                  track++;
+                  group.setVisible(track, !filtered);
+                }
+              }
+            }, true) :
+          group(state -> new CpuSummaryPanel(state, summary), false);
+      data.tracks.addLabelGroup(null, summary.getId(), "CPU Usage", ui);
+      return data;
+    });
   }
 
   public static ListenableFuture<Perfetto.Data.Builder> enumerateCounters(