Add option to post ProfileStartedEvent containing the profile's path.

RELNOTES: None
PiperOrigin-RevId: 206741115

3 files changed, 20 insertions, 5 deletions

diff --git a/src/main/java/com/google/devtools/build/lib/runtime/BlazeCommandDispatcher.java b/src/main/java/com/google/devtools/build/lib/runtime/BlazeCommandDispatcher.java
index 92c1370882..70ae16876d 100644
--- a/src/main/java/com/google/devtools/build/lib/runtime/BlazeCommandDispatcher.java
+++ b/src/main/java/com/google/devtools/build/lib/runtime/BlazeCommandDispatcher.java
@@ -24,6 +24,7 @@ import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableSet;
 import com.google.common.io.Flushables;
 import com.google.common.util.concurrent.UncheckedExecutionException;
+import com.google.devtools.build.lib.buildtool.buildevent.ProfilerStartedEvent;
 import com.google.devtools.build.lib.clock.BlazeClock;
 import com.google.devtools.build.lib.events.Event;
 import com.google.devtools.build.lib.events.EventHandler;
@@ -42,6 +43,7 @@ import com.google.devtools.build.lib.util.LoggingUtil;
 import com.google.devtools.build.lib.util.Pair;
 import com.google.devtools.build.lib.util.io.DelegatingOutErr;
 import com.google.devtools.build.lib.util.io.OutErr;
+import com.google.devtools.build.lib.vfs.Path;
 import com.google.devtools.common.options.OpaqueOptionsData;
 import com.google.devtools.common.options.OptionsParser;
 import com.google.devtools.common.options.OptionsParsingException;
@@ -267,8 +269,12 @@ public class BlazeCommandDispatcher {
     // TODO(ulfjack): Move the profiler initialization as early in the startup sequence as possible.
     // Profiler setup and shutdown must always happen in pairs. Shutdown is currently performed in
     // the afterCommand call in the finally block below.
-    runtime.initProfiler(
-        storedEventHandler, workspace, commonOptions, env.getCommandId(), execStartTimeNanos);
+    Path profilePath =
+        runtime.initProfiler(
+            storedEventHandler, workspace, commonOptions, env.getCommandId(), execStartTimeNanos);
+    if (commonOptions.postProfileStartedEvent) {
+      storedEventHandler.post(new ProfilerStartedEvent(profilePath));
+    }
 
     BlazeCommandResult result = BlazeCommandResult.exitCode(ExitCode.BLAZE_INTERNAL_ERROR);
     PrintStream savedOut = System.out;
diff --git a/src/main/java/com/google/devtools/build/lib/runtime/BlazeRuntime.java b/src/main/java/com/google/devtools/build/lib/runtime/BlazeRuntime.java
index ee4147f666..a8b1d0ae75 100644
--- a/src/main/java/com/google/devtools/build/lib/runtime/BlazeRuntime.java
+++ b/src/main/java/com/google/devtools/build/lib/runtime/BlazeRuntime.java
@@ -263,7 +263,7 @@ public final class BlazeRuntime {
   }
 
   /** Configure profiling based on the provided options. */
-  void initProfiler(
+  Path initProfiler(
       EventHandler eventHandler,
       BlazeWorkspace workspace,
       CommonCommandOptions options,
@@ -273,13 +273,13 @@ public final class BlazeRuntime {
     boolean recordFullProfilerData = false;
     ProfiledTaskKinds profiledTasks = ProfiledTaskKinds.NONE;
     Profiler.Format format = Profiler.Format.BINARY_BAZEL_FORMAT;
+    Path profilePath = null;
     try {
       if (options.enableTracer) {
         format =
             options.enableTracerCompression
                 ? Format.JSON_TRACE_FILE_COMPRESSED_FORMAT
                 : Profiler.Format.JSON_TRACE_FILE_FORMAT;
-        Path profilePath;
         if (options.profilePath != null) {
           profilePath = workspace.getWorkspace().getRelative(options.profilePath);
         } else {
@@ -294,7 +294,7 @@ public final class BlazeRuntime {
         eventHandler.handle(Event.info("Writing tracer profile to '" + profilePath + "'"));
         profiledTasks = ProfiledTaskKinds.ALL_FOR_TRACE;
       } else if (options.profilePath != null) {
-        Path profilePath = workspace.getWorkspace().getRelative(options.profilePath);
+        profilePath = workspace.getWorkspace().getRelative(options.profilePath);
 
         recordFullProfilerData = options.recordFullProfilerData;
         out = profilePath.getOutputStream();
@@ -335,6 +335,7 @@ public final class BlazeRuntime {
     } catch (IOException e) {
       eventHandler.handle(Event.error("Error while creating profile file: " + e.getMessage()));
     }
+    return profilePath;
   }
 
   public FileSystem getFileSystem() {
diff --git a/src/main/java/com/google/devtools/build/lib/runtime/CommonCommandOptions.java b/src/main/java/com/google/devtools/build/lib/runtime/CommonCommandOptions.java
index cef27315e6..4a32b2c405 100644
--- a/src/main/java/com/google/devtools/build/lib/runtime/CommonCommandOptions.java
+++ b/src/main/java/com/google/devtools/build/lib/runtime/CommonCommandOptions.java
@@ -204,6 +204,14 @@ public class CommonCommandOptions extends OptionsBase {
   public boolean enableTracerCompression;
 
   @Option(
+      name = "experimental_post_profile_started_event",
+      defaultValue = "false",
+      documentationCategory = OptionDocumentationCategory.LOGGING,
+      effectTags = {OptionEffectTag.AFFECTS_OUTPUTS, OptionEffectTag.BAZEL_MONITORING},
+      help = "If set, Bazel will post the ProfilerStartedEvent including the path to the profile.")
+  public boolean postProfileStartedEvent;
+
+  @Option(
       name = "profile",
       defaultValue = "null",
       documentationCategory = OptionDocumentationCategory.LOGGING,