Add profile task for file system traversal.

PiperOrigin-RevId: 359240912
diff --git a/src/main/java/com/google/devtools/build/lib/profiler/ProfilerTask.java b/src/main/java/com/google/devtools/build/lib/profiler/ProfilerTask.java
index 287a993..dacf785 100644
--- a/src/main/java/com/google/devtools/build/lib/profiler/ProfilerTask.java
+++ b/src/main/java/com/google/devtools/build/lib/profiler/ProfilerTask.java
@@ -76,6 +76,7 @@
   REMOTE_CACHE_CHECK("remote action cache check"),
   REMOTE_DOWNLOAD("remote output download"),
   REMOTE_NETWORK("remote network"),
+  FILESYSTEM_TRAVERSAL("filesystem traversal"),
   UNKNOWN("Unknown event");
 
   private static class Threshold {
diff --git a/src/main/java/com/google/devtools/build/lib/skyframe/BUILD b/src/main/java/com/google/devtools/build/lib/skyframe/BUILD
index 3b42cd4..ffdb17c 100644
--- a/src/main/java/com/google/devtools/build/lib/skyframe/BUILD
+++ b/src/main/java/com/google/devtools/build/lib/skyframe/BUILD
@@ -2145,6 +2145,7 @@
         "//src/main/java/com/google/devtools/build/lib/collect/nestedset",
         "//src/main/java/com/google/devtools/build/lib/concurrent",
         "//src/main/java/com/google/devtools/build/lib/events",
+        "//src/main/java/com/google/devtools/build/lib/profiler",
         "//src/main/java/com/google/devtools/build/lib/skyframe/serialization/autocodec",
         "//src/main/java/com/google/devtools/build/lib/util",
         "//src/main/java/com/google/devtools/build/lib/vfs",
diff --git a/src/main/java/com/google/devtools/build/lib/skyframe/RecursiveFilesystemTraversalFunction.java b/src/main/java/com/google/devtools/build/lib/skyframe/RecursiveFilesystemTraversalFunction.java
index 3bba228..f742794 100644
--- a/src/main/java/com/google/devtools/build/lib/skyframe/RecursiveFilesystemTraversalFunction.java
+++ b/src/main/java/com/google/devtools/build/lib/skyframe/RecursiveFilesystemTraversalFunction.java
@@ -32,6 +32,9 @@
 import com.google.devtools.build.lib.collect.nestedset.NestedSet;
 import com.google.devtools.build.lib.collect.nestedset.NestedSetBuilder;
 import com.google.devtools.build.lib.events.Event;
+import com.google.devtools.build.lib.profiler.Profiler;
+import com.google.devtools.build.lib.profiler.ProfilerTask;
+import com.google.devtools.build.lib.profiler.SilentCloseable;
 import com.google.devtools.build.lib.skyframe.RecursiveFilesystemTraversalValue.FileType;
 import com.google.devtools.build.lib.skyframe.RecursiveFilesystemTraversalValue.ResolvedFile;
 import com.google.devtools.build.lib.skyframe.RecursiveFilesystemTraversalValue.ResolvedFileFactory;
@@ -139,7 +142,9 @@
   public SkyValue compute(SkyKey skyKey, Environment env)
       throws RecursiveFilesystemTraversalFunctionException, InterruptedException {
     TraversalRequest traversal = (TraversalRequest) skyKey.argument();
-    try {
+    try (SilentCloseable c =
+        Profiler.instance()
+            .profile(ProfilerTask.FILESYSTEM_TRAVERSAL, traversal.getRoot().toString())) {
       // Stat the traversal root.
       FileInfo rootInfo = lookUpFileInfo(env, traversal);